WorldWideScience

Sample records for dye tracer studies

  1. Estimation of Fluorescent Dye Amount in Tracer Dye Test

    Science.gov (United States)

    Pekkan, Emrah; Balkan, Erman; Balkan, Emir

    2015-04-01

    Karstic groundwater is more influenced by human than the groundwater that disperse in pores. On the other hand karstic groundwater resources, in addition to providing agricultural needs, livestock breeding, drinking and domestic water in most of the months of the year, they also supply drinking water to the wild life at high altitudes. Therefore sustainability and hydrogeological investigation of karstic resources is critical. Tracing techniques are widely used in hydrologic and hydrogeologic studies to determine water storage, flow rate, direction and protection area of groundwater resources. Karanfil Mountain (2800 m), located in Adana, Turkey, is one of the karstic recharge areas of the natural springs spread around its periphery. During explorations of the caves of Karanfil mountain, a 600 m deep cave was found by the Turkish and Polish cavers. At the bottom of the cave there is an underground river with a flow rate of approximately 0.5 m3/s during August 2014. The main spring is located 8 km far from the cave's entrance and its mean flow rate changes between 3.4 m3/s and 0.21 m3/s in March and September respectively according to a flowrate observation station of Directorate of Water Works of Turkey. As such frequent storms, snowmelt and normal seasonal variations in rainfall have a significant and rapid effect on the volume of this main spring resource. The objective of our research is to determine and estimate dye amount before its application on the field inspired from the previously literature on the subject. This estimation is intended to provide a preliminary application of a tracer test of a karstic system. In this study dye injection, inlet point will be an underground river located inside the cave and the observation station will be the spring that is approximately 8 km far from the cave entrance. On the other hand there is 600 meter elevation difference between cave entrance and outlet spring. In this test Rodamin-WT will be used as tracer and the

  2. Observations and modeling of a tidal inlet dye tracer plume

    Science.gov (United States)

    Feddersen, Falk; Olabarrieta, Maitane; Guza, R. T.; Winters, D.; Raubenheimer, Britt; Elgar, Steve

    2016-10-01

    A 9 km long tracer plume was created by continuously releasing Rhodamine WT dye for 2.2 h during ebb tide within the southern edge of the main tidal channel at New River Inlet, NC on 7 May 2012, with highly obliquely incident waves and alongshore winds. Over 6 h from release, COAWST (coupled ROMS and SWAN, including wave, wind, and tidal forcing) modeled dye compares well with (aerial hyperspectral and in situ) observed dye concentration. Dye first was transported rapidly seaward along the main channel and partially advected across the ebb-tidal shoal until reaching the offshore edge of the shoal. Dye did not eject offshore in an ebb-tidal jet because the obliquely incident breaking waves retarded the inlet-mouth ebb-tidal flow and forced currents along the ebb shoal. The dye plume largely was confined to <4 m depth. Dye was then transported downcoast in the narrow (few 100 m wide) surfzone of the beach bordering the inlet at 0.3 m s-1 driven by wave breaking. Over 6 h, the dye plume is not significantly affected by buoyancy. Observed dye mass balances close indicating all released dye is accounted for. Modeled and observed dye behaviors are qualitatively similar. The model simulates well the evolution of the dye center of mass, lateral spreading, surface area, and maximum concentration, as well as regional ("inlet" and "ocean") dye mass balances. This indicates that the model represents well the dynamics of the ebb-tidal dye plume. Details of the dye transport pathways across the ebb shoal are modeled poorly perhaps owing to low-resolution and smoothed model bathymetry. Wave forcing effects have a large impact on the dye transport.

  3. pH dependence and unsuitability of fluorescein dye as a tracer for pesticide mobility studies in acid soil

    Science.gov (United States)

    Chris Peterson

    2009-01-01

    The mobility of fluorescein and bromide used as tracers in packed soil columns was investigated.Five different soils were used in two application methods: soil surface application and soil incorporation, both of which simulate accepted methods of soil application of termiticides to prevent structural infestation. The...

  4. Using the dye tracer for visualization of preferential flow in macro and micro-scale

    Science.gov (United States)

    Kodesova, Radka; Nemecek, Karel; Kodes, Vit; Fer, Miroslav; Jirku, Veronika; Nikodem, Antonin; Zigova, Anna; Jaksik, Ondrej; Kocarek, Martin

    2010-05-01

    Study is focused on the visualization of the preferential flow in different soil types and their horizons using the dye tracer experiment. Study was performed in the Haplic Luvisol in Hněvčeves and the Haplic Cambisol in Humpolec in the Czech Republic. The 100 (Haplic Luvisol) and 50 (Haplic Cambisol) liters of solute of dye Brilliant Blue FCF (5g/litr) was infiltrated on a 1 x 1 m plot (applying an initial ponding depth of 10 and 5 cm, respectively) immediately after the wheat harvest. On the next day, one half of the plot was sliced horizontally and another half vertically to study the dye distribution within the soil profile to the depth of 100 cm (macro-scale). The 3-D image of the dye distribution was created. In addition, the thin soil sections were made and micromorphological images were used to study a soil aggregate structure and dye distribution in micro-scale. The staining patterns within the vertical and horizontal sections documented very different nature of the preferential flow in different soil types and also within the soil profiles. Images of the Haplic Luvisol showed that while dye tracer was partly regularly transported and only some isolated domains were visible in the surface Ap1 horizon, the preferential flow occurred in the subsurface horizons. The preferential flow in the upper subsurface Ap2 horizon (plow pan) was caused by the gravitational biopores in the very compact matrix structure, which considerably slowed down the dye transport. In the case of deeper horizons (Bt1 and Bt2), the preferential flow occurred due to the gravitational biopores and extensively developed prismatic structure (small and very large aggregates in the Bt1 and Bt2 horizon respectively), which was highly affected by clay coatings. Even better characterization of the preferential flow particularly in these two horizons was obtained, when the same ponding dye infiltration experiment was performed directly on the top of the Bt1 horizon. Images of the Haplic

  5. Exotic tracers for atmospheric studies

    Energy Technology Data Exchange (ETDEWEB)

    Lovelock, J.E. (Brazzos Ltd., Launceston (UK)); Ferber, G.J. (National Oceanic and Atmospheric Administration, Silver Spring, MD (USA). Air Resources Lab.)

    1982-01-01

    Tracer materials can be injected into the atmosphere to study transport and dispersion processes and to validate air pollution model calculations. Tracers should be inert, non-toxic and harmless to the environment. Tracers for long-range experiments, where dilution is very great, must be measurable at extremely low concentrations, well below the parts per trillion level. Compounds suitable for long-range tracer work are rare and efforts should be made to reserve them for meteorological studies, barring them from commercial uses which would increase atmospheric background concentrations. The use of these exotic tracers, including certain perfluorocarbons and isotopically labelled methanes, should be coordinated within the meteorological community to minimize interferences and maximise research benefits.

  6. Exotic tracers for atmospheric studies

    Science.gov (United States)

    Lovelock, James E.; Ferber, Gilbert J.

    Tracer materials can be injected into the atmosphere to study transport and dispersion processes and to validate air pollution model calculations. Tracers should be inert, non-toxic and harmless to the environment. Tracers for long-range experiments, where dilution is very great, must be measurable at extremely low concentrations, well below the parts per trillion level. Compounds suitable for long-range tracer work are rare and efforts should be made to reserve them for meteorological studies, barring them from commercial uses which would increase atmospheric background concentrations. The use of these exotic tracers, including certain perfluorocarbons and isotopically labelled methanes, should be coordinated within the meteorological community to minimize interferences and maximize research benefits.

  7. Sonde for Downhole Measurement of Water Turbidity and Dye Tracer Concentration

    OpenAIRE

    Schnegg, Pierre-André; Bossy, F.

    2005-01-01

    A new flow-through field fluorometer sonde has been designed for use in downhole tracer tests in 2’’ boreholes. The instrument is capable of determining the partial concentration of two dye tracers present simultaneously in the water. In addition, turbidity can be measured if the water is free of tracers. Although the sonde is aimed at boreholed hydrological investigations, it can also be used in surface waters.

  8. Snowmelt Infiltration Into Alpine Soils Visualised In Situ With A Dye Tracer Method

    Science.gov (United States)

    Stähli, M.; Bayard, D.; Wydler, H.; Flühler, H.

    The mechanisms governing snowmelt infiltration into frozen or unfrozen alpine soils are complex due to the fact that many factors influence the flow paths from the snow pack into the soil, such as soil type, slope inclination and aspect, ground vegetation and the occurrence and persistence of ice on the soil surface or in the frozen soil. Dye tracer experiments are a feasible method to provide a better insight into the real distribution of such water flow paths, which can be very preferential. The main objec- tive of this study was to test the potential of dye tracer methods for visualising in situ snowmelt infiltration at alpine sites and to gain quantitative information on snowmelt infiltration into frozen and unfrozen soils. Field experiments were carried out during winter 2000/01 in southern Switzerland at Hannigalp (2100 m a.s.l.), where a 60 to 80 cm deep Ferric Podzole facing north-west is covered by sparse Ericaceae, and at Gd-St-Bernard pass (2500 m a.s.l.), where a shallow stony Ranker facing south is cov- ered with grass. At the beginning of December a dye tracer (Brilliant Blue FCF) was applied on the soil surface covering an area 5 m downhill x 1.5 m horizontally. At dif- ferent stages during the snowmelt (March to June) we excavated vertical soil profiles on these plots (from below upwards) and took photographs of the stained soil profiles using a digital camera. From these digital images the areas of the soil profiles stained with the dye tracer were determined using a supervised classification method, and the depth distribution of areal coverage of dye tracer was calculated. The water flow pat- tern showed to be extremely heterogeneous in the Hannigalp soil, and more uniform in the Gd-St-Bernard soil. Already in an early stage of the snowmelt we observed infil- tration down to 40 to 60 cm, indicating a relatively high soil matrix infiltration rate at Gd-St-Bernard and efficient preferential flow channels (e.g. along roots) at Hannigalp. Soil frost

  9. Dye tracer infiltration technique to investigate macropore flow paths in Maka Mountain, Yunnan Province, China

    Institute of Scientific and Technical Information of China (English)

    张家明; 徐则民

    2016-01-01

    In order to investigate the differences of macropores vertical distribution under different surface plants, and to assess the influences of root systems, organic matter and texture on macropore flow paths, two dye tracer infiltration experiments were performed in slopes under two different plants (Campylotropis polyantha (Franch.) Schindl vs.Cynodon dactylon(Linn.) Pers). Dye tracer infiltration experiments with field observations and measurements of soil properties were combined. Results show that the discrepancy in macropores distribution between two slopes under different plants is significant. Root systems have significant effects on macropore flow paths distribution and the effect become more pronounced as the diameter of roots become larger. Organic matter and stone are important factors to affect macropores distribution. Root-soil interface, inter-aggregate macropore and stone-soil interface are important macropore flow paths in well vegetated slopes.

  10. Characterization of rhodamine-123 as a tracer dye for use in in vitro drug transport assays.

    Directory of Open Access Journals (Sweden)

    Samantha Forster

    Full Text Available Fluorescent tracer dyes represent an important class of sub-cellular probes and allow the examination of cellular processes in real-time with minimal impact upon these processes. Such tracer dyes are becoming increasingly used for the examination of membrane transport processes, as they are easy-to-use, cost effective probe substrates for a number of membrane protein transporters. Rhodamine 123, a member of the rhodamine family of flurone dyes, has been used to examine membrane transport by the ABCB1 gene product, MDR1. MDR1 is viewed as the archetypal drug transport protein, and is able to efflux a large number of clinically relevant drugs. In addition, ectopic activity of MDR1 has been associated with the development of multiple drug resistance phenotype, which results in a poor patient response to therapeutic intervention. It is thus important to be able to examine the potential for novel compounds to be MDR1 substrates. Given the increasing use rhodamine 123 as a tracer dye for MDR1, a full characterisation of its spectral properties in a range of in vitro assay-relevant media is warranted. Herein, we determine λmax for excitation and emission or rhodamine 123 and its metabolite rhodamine 110 in commonly used solvents and extraction buffers, demonstrating that fluorescence is highly dependent on the chemical environment: Optimal parameters are 1% (v/v methanol in HBSS, with λex = 505 nm, λem = 525 nm. We characterise the uptake of rhodamine 123 into cells, via both passive and active processes, and demonstrate that this occurs primarily through OATP1A2-mediated facilitated transport at concentrations below 2 µM, and via micelle-mediated passive diffusion above this. Finally, we quantify the intracellular sequestration and metabolism of rhodamine 123, demonstrating that these are both cell line-dependent factors that may influence the interpretation of transport assays.

  11. Quantifying the Preferential Flow by Dye Tracer in the North China Plain

    Institute of Scientific and Technical Information of China (English)

    Qinghua Wu; Chunlei Liu; Wenjing Lin; Meng Zhang; Guiling Wang; Fawang Zhang

    2015-01-01

    The preferential flow plays a vital role on the infiltration of irrigation or rainfall. The ob-jective of this study was to quantify preferential flow in the processing of irrigation infiltration in the field scale. Tests of different initial soil water contents and irrigation intensities were conducted using Brilliant Blue FCF (C.I.42090) dye tracer in Luancheng County of the North China Plain. The results showed that the percentages of infiltration by the preferential flow for irrigation depth of 25, 50, and 75 mm were 16.67%, 43.67%, and 34.17%, with 19.72%, 61.42%, 66.64%of dyed areas in the soil profile, respectively, which indicated that preferential flow was enhanced with increasing irrigation intensity, but reduced when the irrigation intensity was over 50 mm. The percentages of preferential flow for 75 and 180 mm previous irrigation producing different initial soil water contents were 23.26%and 18.97%, with 53.23% and 39.94% of dyed areas in the soil profile, respectively. Compared with the 75 mm without previous irrigation, the results indicated that higher initial soil water contents restrained the preferential flow in the field. Therefore, intermittent irrigation and low irrigation intensity patterns, and larger depth of plowing would be suggested to reduce the preferential flow which would increase the soil water utilization efficiency and reduce pollution risk of pesticide and fertilizer to groundwater.

  12. Dye Tracer Technique and Color Image Analysis For Describing Saturation State and 3d Axi-symmetrical Flow Pattern

    Science.gov (United States)

    Abriak, N. E.; Gandola, F.; Haverkamp, R.

    Dye tracer techniques have been widely used for visualising water flow pattern in soils and particularly, for determining the volumetric water content in a one dimensional and two dimensional laboratory experiments. The present study deals a 3 dimensional laboratory experiment (axi-symmetrical condition) using color visualisation technique and the image analysis technique for determining the spatial distribution of the water content. The infiltration of a dye (fluorescein) mixed with water is achieved under ax- isymmetrical condition in a Plexiglas tank (50t'50t'60cm) filled with a low saturated sand. Both infiltration and drainage processes are visualised under blue light condi- tion and recorded on videotape. The image analysis technique used for determining the saturation state is based on the use of a limited colors palette which allows to quan- tify the evolution of the saturation state in the sand. Simultaneously, nine tensiometers connected to a data acquisition system, are used to determine the negative water pres- sure in the sand. The measurement of the succion values confirms the existence of a second water wetting front (after the dye flow) due to the initial mobile water content in the sand.

  13. Combined Methylene Blue Dye andRadioactive Tracer Technique for Sentinel Lymph Node Localization in Early Breast Cancer

    Directory of Open Access Journals (Sweden)

    Abdolrasoul Talei

    2010-10-01

    Full Text Available Background: Sentinel lymph node biopsy is a technique used to identify the axillary node most likely to contain tumor cells that have metastasized from a primarycarcinoma of the breast. This technique provides accurate staging with fewer complications than axillary dissection and may result in decreased costs. We designed the present study to determine the accuracy and success rate of a combined blue dyeand radioactive tracer technique in sentinel node localization. Methods: This prospective study included 70 patients with early stage (tumor>5cm; T1, T2 operable breast cancer and nonpalpable axillary lymphadenopathy seen between 2005 and 2009. Patients underwent sentinel lymph node localization using 4mL of blue dye combined with radioactive colloid. After identification and removal of the sentinel node(s, the axilla was checked for any residual radioactivity. A sentinelnode was defined as any node that was hot, hot and blue or only blue.Results:The sentinel node was identified in 66 patients with a detection rate of 94.2%,and a mean of 1.5 sentinel nodes were identified and harvested (range of 1-4. In 23cases, the sentinel lymph node contained metastatic disease on pathological assessment.There was no pathological evidence of any metastases in the sentinel node in the remaining 43 patients. All sentinel lymph nodes were located in level I of the axillary region. In four patients, no sentinel lymph node was found, so axillary dissection was performed. The sensitivity of the procedure in predicting further axillary disease was 95.6% with a specificity of 97.6%.Conclusion: The present study describes the blue dye and radioisotope localization technique as successful in identifying the sentinel lymph node in early-stage breast cancer patients.

  14. Tracer studies of nitrogen assimilation in yeast.

    Science.gov (United States)

    ABRAMS, R; HAMMARSTEN, E

    1949-01-01

    By using N(15) as a tracer the assimilation of ammonia by the yeast, Torulopsis utilis, has been studied. It has been shown that: 1. There was no measurable incorporation of N in the protein or polynucleotide purine of carbon-starved yeast. 2. When ammonia is added to nitrogen-starved yeast there is a long lag period before division begins during which the yeast rapidly synthesizes protein, this process being accompanied by a turnover of polynucleotide purine. There was no significant dilution of the N(15)H(4) (+) of the medium by ordinary NH(4) (+). 3. When yeast containing N(15) is allowed to divide and grow in ordinary ammonia, the total amount of N(15) in the yeast remains constant. The dicarboxylic amino acids are most diluted, while arginine and nucleic acid guanine are not diluted at all.

  15. TRACER STUDY OF RTU GRADUATES: AN ANALYSIS

    Directory of Open Access Journals (Sweden)

    Thelma L. Ramirez

    2014-01-01

    Full Text Available This paper aimed to determine if the field of specialization in the different colleges of RTU graduates and their academic-acquired skills and competencies are related to their present occupations. A modified Graduate Tracer Study (GTS instrument was utilized to gather the quantitative data. Out of 500 questionnaires administered, there were 250 graduates returned answered questionnaires representing the three Colleges: Education, Arts and Sciences, Business and Entrepreneurial Technology. A face to face interview was also conducted in order to support the gathered data. The SPSS was used to generate results from the acquired quantitative data using the frequency counts, percentage and the Chi-square goodness of fit test. The findings revealed that the graduates claimed that their knowledge, academic-acquired skills and competencies contributed greatly in their job performance. The Chi-square goodness of fit proved that there is a significant relationship between the graduates’ fields of specialization and their occupations after graduation. Likewise, the academic-acquired skills and competencies of the graduates are relevant to their chosen occupations. The results further proved that RTU produces marketable and appropriately trained graduates with the majority landing in course-related jobs within a short period after graduation. The study also indicates that the RTU graduates possess the skills and competencies necessary to succeed in this competitive world. However eexpansion of tie-ups with private business entities is made to at least maintain the high employability level of the graduates.

  16. National Biomedical Tracer Facility: Project definition study

    Energy Technology Data Exchange (ETDEWEB)

    Heaton, R.; Peterson, E. [Los Alamos National Lab., NM (United States); Smith, P. [Smith (P.A.) Concepts and Designs (United States)

    1995-05-31

    The Los Alamos National Laboratory is an ideal institution and New Mexico is an ideal location for siting the National Biomedical Tracer Facility (NBTF). The essence of the Los Alamos proposal is the development of two complementary irradiation facilities that combined with our existing radiochemical processing hot cell facilities and waste handling and disposal facilities provide a low cost alternative to other proposals that seek to satisfy the objectives of the NBTF. We propose the construction of a 30 MeV cyclotron facility at the site of the radiochemical facilities, and the construction of a 100 MeV target station at LAMPF to satisfy the requirements and objectives of the NBTF. We do not require any modifications to our existing radiochemical processing hot cell facilities or our waste treatment and disposal facilities to accomplish the objectives of the NBTF. The total capital cost for the facility defined by the project definition study is $15.2 M. This cost estimate includes $9.9 M for the cyclotron and associated facility, $2.0 M for the 100 MeV target station at LAMPF, and $3.3 M for design.

  17. Sistem Pre Kompilasi Data Tracer Studi Online Ditjen Belmawa Ristekdikti (Studi Kasus: Politeknik Harapan Bersama

    Directory of Open Access Journals (Sweden)

    Very Kurnia Bakti

    2017-01-01

    Full Text Available Tracer studi merupakan salah satu upaya yang diharapkan dapat menyediakan informasi untuk mengevaluasi hasil pendidikan di Politeknik Harapan Bersama dari kuisioner yang diberikan kepada alumni. Kegiatan tracer studi ini sudah dilaksanakan secara online, namun masih terdapat kendala pada bagian sistem yang digunakan saat ini, hal tersebut menyebabkan Politeknik Harapan Bersama tidak dapat melaporkan / mengunggah hasil tracer studi kepada Ditjen Belmawa Ristekdikti, dimana form kuisioner dan data export tracer studi yang dihasilkan berbeda dengan kebutuhan seperti yang tercantum pada surat edaran No. 313/B/SE/2016 tentang pelaksanaan tracer studi di tingkat perguruan tinggi. Mengingat pentingnya tracer studi sebagai umpan balik bagi Politeknik Harapan Bersama, maka perlu solusi untuk mengatasi kekurangan sistem ini. Dengan merubah sistem yang ada dengan sistem tracer studi yang baru merupakan solusi yang tepat dalam permasalahan ini. Sistem tracer studi yang baru mampu menghasilkan data tracer studi alumni dan pengisian form kuisioner sesuai dengan standar Ditjen Belmawa Ristekdikti yang dapat diunggah sistem tracer studi ristekdikti.

  18. Direct-push delivery of dye tracers for direct documentation of solute distribution in clay till

    DEFF Research Database (Denmark)

    Christiansen, Camilla Maymann; Damgaard, Ida; Broholm, Mette Martina

    2012-01-01

    at an uncontaminated, naturally fractured, basal clay till site (K∼10-7-10-10-m/s) in 2008-2009. A mixture of tracers (brilliant blue, fluorescein, and Rhodamine WT), the characteristics of which are comparable to several current remediation amendments, was delivered in aqueous solution at pressures of ∼5-10 bar...

  19. COMPARATIVE STUDY OF TWO DYEING METHODS USING REACTIVE DYE

    Directory of Open Access Journals (Sweden)

    HINOJOSA Belén

    2016-05-01

    Full Text Available Environment preservation is a common worry not only for people but for companies as well. Industry is more and more concern about the necessity of developing new and more respectful processes. Dye is one of the most important processes in the textile industry but it is also considered as no too safe regarding environment issues. This process uses large amounts of water and generates big volumes of wastewater. Following this issue, new regulations and laws emerge to control the waste generated. This leads to the companies and increased costs in terms of wastewater treatments and high water consumption. In this research we compare two systems on garment finishing application, the conventional bath process and the new Ecofinish system that is able to save water and product. To compare these processes, we carried out a reactive dyeing using both systems in order to determine the quality differences in the final product. For this purpose, the samples have been tested to washing and rubbing fastness, according to UNE EN ISO 105 C10 and UNE- EN ISO 105 X12 standards, respectively. This study confirms that this system achieves water savings and reduces the wastewater produced, getting a good dyeing. This process can be considered as an alternative to the conventional one.

  20. National Biomedical Tracer Facility. Project definition study

    Energy Technology Data Exchange (ETDEWEB)

    Schafer, R.

    1995-02-14

    We request a $25 million government-guaranteed, interest-free loan to be repaid over a 30-year period for construction and initial operations of a cyclotron-based National Biomedical Tracer Facility (NBTF) in North Central Texas. The NBTF will be co-located with a linear accelerator-based commercial radioisotope production facility, funded by the private sector at approximately $28 million. In addition, research radioisotope production by the NBTF will be coordinated through an association with an existing U.S. nuclear reactor center that will produce research and commercial radioisotopes through neutron reactions. The combined facilities will provide the full range of technology for radioisotope production and research: fast neutrons, thermal neutrons, and particle beams (H{sup -}, H{sup +}, and D{sup +}). The proposed NBTF facility includes an 80 MeV, 1 mA H{sup -} cyclotron that will produce proton-induced (neutron deficient) research isotopes.

  1. Development of radioisotope tracer technology

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Joon Ha; Lee, Myun Joo; Jung, Sung Hee; Park, Soon Chul; Lim, Dong Soon; Kim, Jae Ho; Lee, Jae Choon; Lee, Doo Sung; Cho, Yong Suk; Shin, Sung Kuan

    2000-04-01

    The purpose of this study is to develop the radioisotope tracer technology, which can be used in solving industrial and environmental problems and to build a strong tracer group to support the local industries. In relation to the tracer technology in 1999, experiments to estimate the efficiencies of a sludge digester of a waste water treatment plant and a submerged biological reactor of a dye industry were conducted. As a result, the tracer technology for optimization of facilities related to wastewater treatment has been developed and is believed to contribute to improve their operation efficiency. The quantification of the experimental result was attempted to improve the confidence of tracer technology by ECRIN program which basically uses the MCNP simulation principle. Using thin layer activation technique, wear of tappet shim was estimated. Thin layer surface of a tappet shim was irradiated by proton beam and the correlation between the measured activity loss and the amount of wear was established. The equipment was developed to adjust the energy of proton which collides with the surface of tappet. The tracer project team has participated into the tracer test for estimating the efficiency of RFCC system in SK cooperation. From the experiment the tracer team has obtained the primary elements to be considered for judging the efficiency of RFCC unit. By developing the tracer techniques to test huge industrial units like RFCC, the tracer team will be able to support the local industries that require technical services to solve any urgent trouble. (author)

  2. Tracer Studies In A Laboratory Beach Subjected To Waves

    Science.gov (United States)

    This work investigated the washout of dissolved nutrients from beaches due to waves by conducting tracer studies in a laboratory beach facility. The effects of waves were studied in the case where the beach was subjected to the tide, and that in which no tidal action was present...

  3. Tracer Studies In A Laboratory Beach Subjected To Waves

    Science.gov (United States)

    This work investigated the washout of dissolved nutrients from beaches due to waves by conducting tracer studies in a laboratory beach facility. The effects of waves were studied in the case where the beach was subjected to the tide, and that in which no tidal action was present...

  4. Ground-penetrating radar images of a dye tracer test within the unsaturated zone at the Susquehanna-Shale Hills CZO

    Science.gov (United States)

    Pitman, Lacey M.

    Dye tracer and time-lapse ground-penetrating radar (GPR) were used to image preferential flow paths in the shallow, unsaturated zone on hillslopes in two adjacent watersheds within the Susquehanna-Shale Hills Critical Zone Observatory (CZO). At each site we injected about 50 L of water mixed with brilliant blue dye (4 g/L) into a trench cut perpendicular to the slope (˜1.0 m long by ˜0.20 m wide by ˜0.20 m deep) to create a line of infiltration. GPR (800 MHz antennae with constant offset) was used to monitor the movement of the dye tracer downslope on a 1.0 m x 2.0 m grid with a 0.05 m line spacing. The site was then excavated and the stained pathways photographed to document the dye movement. We saw a considerable difference in the pattern of shallow preferential flow between the two sites despite similar soil characteristics and slope position. Both sites showed dye penetrating down to saprolite (˜0.40 m); however, lateral flow migration between the two sites was different. At the Missed Grouse field site, the lateral migration was ˜0.55 m as an evenly dispersed plume, but at distance of 0.70 m a finger of dye was observed. At the Shale Hills field site, the total lateral flow was ˜0.40 m, dye was barely visible until the excavation reached ˜0.10 m, and there was more evidence of distinct fingering in the vertical direction. Based on laboratory and field experiments as well as processing of the radargrams, the following conclusions were drawn: 1) time-lapse GPR successfully delineated the extent of lateral flow, but the GPR resolution was insufficient to detect small fingers of dye; 2) there was not a distinct GPR reflection at the regolith-saprock boundary, but this interface could be estimated from the extent of signal attenuation; 3) the preliminary soil moisture conditions may explain differences in the extent of infiltration at the two sites; 4) rapid infiltration into the underlying saprock limited the extent of shallow lateral flow at both sites and

  5. Study on Dyeing Behavior of Modified Flax

    Institute of Scientific and Technical Information of China (English)

    ZHENG Lai-jiu; LI Hong; LIU Jian-yu

    2004-01-01

    The study of dyeability of the modified flax that uses dye-uptake to reflect its modifying effect is reported in this paper. The optimal technological condition is that the concentration of the modifying agent is 4g/l, and NaOH is 6g/l at liquor ratio of 1:30 for 60 min. at 85℃.Dyeability include uptake rate and color fastness. Dye-uptake of the modified flax is twice more than that of the unmodified. And their color fastness doesn't fall and some of them raise 0.5-1 level.

  6. Study on Application of Natural Plant Dye Gardenia on Cotton Coloration and the Dyeing Mechanism

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lan; SHAO Jian-zhong

    2006-01-01

    Based on the analysis of the structure and properties of gardenia, the gardenia was extracted in neutral bath. The mordant dyeing of cotton, including pre-mordant, one-bath and post-mordant were studied, and the dyeing properties such as dye K/S value and color fastness were investigated.According to the structure and property of mordants including alum, copper sulfate, iron sulfate and rare earth,the interaction mechanisms among gardenia, mordant and cotton fibers were analyzed and the processing factors affecting the mordant dyeing were discussed. As a result,gardenia showed favorable dyeing performance on cotton.The soaping color fastness and crocking fastness were improved by 0.5 - 1 grade after fixation process with the selected dye-fixing agent and optimized process conditions.The dyeing process and fixation process were optimized.

  7. 中华墨汁作为前哨淋巴结活检新型示踪剂的实验研究%Experimental Study of Chinese Ink as a New Type of Dye Tracer in Sentinel Lymph Node Biopsy

    Institute of Scientific and Technical Information of China (English)

    曹勤洪; 王水; 徐鲲; 刘晓安; 刘力嘉

    2006-01-01

    Objective: To investigate the potential clinical value of Chinese ink as a tracer in dye-directed sentinel lymph node biopsy. Methods: Forty-two female rabbits were randomly divided into 7 groups. The breast drainage lymphatic vessels and nodes in axilla were exposed by surgery. Under the papillae of the second pair of breast, 0.1 mL Chinese ink dilution at concentrations of 0.1%, 1%, 10%, 50% and 100% and isosulfan blue (IB, 1.0%) were injected. The movement of ink in lymphatic chain was investigated, and the number of stained nodes and their staining and washout time ware recorded. The first stained lymph node that was followed through lymphatic drainage was identified as the sentinel lymph node (SLN). The SLNs were dissected and prepared for histological observation 5 min, 1 h and 2 weeks after stained. Blood samples were harvested and tested before and 2 weeks after injection. The hearts, lungs, livers and kidneys were dissected after a period of post-operation observation and sent for pathologic examination. Results: No obvious differences were observed among the staining time of SLNs and the second lymph node using ink at different concentrations (P>0.05). But they were obviously longer than that of IB (P<0.05). The mean number of nodes obtained was nearly the same (P>0.05). It was too light for gross visual inspection when nodes were stained by ink at the concentration of 0.1%. Nodes stained by IB faded 33.9 min after stained. And carbon staining seemed permanent without any visible decline after 2 weeks. Carbon particles were found to be in the sinus of lymph nodes that were obtained 5 min after stained, and then was phagocytosed when they were stained using Chinese ink at concentration of higher than 20.0%. No obvious changes were investigated in blood test and vital organ pathologic examination. Conclusion: Chinese ink is potentially a novel type of dye tracer in SLN biopsy.

  8. Experimental quantification of solute transport through the vadose zone under dynamic boundary conditions with dye tracers and optical methods.

    Science.gov (United States)

    Cremer, Clemens; Neuweiler, Insa

    2017-04-01

    Knowledge of subsurface solute transport processes is vital to investigate e.g. groundwater contamination, nutrient uptake by plant roots and to implement remediation strategies. Beside field measurements and numerical simulations, physical laboratory experiments represent a way to establish process understanding and furthermore validate numerical schemes. Atmospheric forcings, such as erratically varying infiltration and evaporation cycles, subject the shallow subsurface to local and temporal variations in water content and associated hydraulic conductivity of the prevailing porous media. Those variations in material properties can cause flow paths to differ between upward and downward flow periods. Thereby, the unsaturated subsurface presents a highly complicated, dynamic system. Following an extensive systematical numerical investigation of flow and transport through bimodal, unsaturated porous media under dynamic boundary conditions (Cremer et al., 2016), we conduct physical laboratory experiments in a 22 cm x 8 cm x 1 cm flow cell where we introduce structural heterogeneity in the form sharp material interfaces between different porous media. In all experiments, a constant pressure head is implemented at the lower boundary, while cyclic infiltration-evaporation phases are applied at the soil surface. As a reference case a stationary infiltration with a rate corresponding to the cycle-averaged infiltration rate is applied. By initial application of dye tracers, solute transport within the domain is visualized such that transport paths and redistribution processes can be observed in a qualitative manner. Solute leaching is quantified at the bottom outlet, where breakthrough curves are obtained via spectroscopy. Liquid and vapor flow in and out of the domain is obtained from multiple balances. Thereby, the interplay of material structural heterogeneity and alternating flow (transport) directions and flow (transport) paths is investigated. Results show lateral

  9. Studies of Tracer Dispersion and Fluid Flow in Porous Media

    Energy Technology Data Exchange (ETDEWEB)

    Rage, T.

    1996-12-31

    This doctoral thesis explores the connection between the topology of a porous medium and its macroscopic transport properties and is based on computerized simulation. In porous media, both diffusion and convection contribute to the dispersion of a tracer and their combined effect is emphasized. The governing equations are solved numerically, using finite differences and Monte Carlo technique. The influence of finite Reynolds number on the outcome of echo-experiments is discussed. Comparing experiments and simulations it is found that nonlinear inertial forces lead to a visible deformation of a returned tracer at surprisingly small Reynolds numbers. In a study of tracer dispersion and fluid flow in periodic arrays of discs it is demonstrated that the mechanisms of mechanical dispersion in periodic media and in natural (non-periodic) porous media are essentially different. Measurements of the percolation probability distribution of a sandstone sample is presented. Local porosity theory predicts that this simple geometric function of a porous medium is of dominant importance for its macroscopic transport properties. It is demonstrated that many aspects of transport through fractures can be studied by using simple but realistic models and readily available computer resources. An example may be the transport of hydrocarbon fluids from the source rock to a reservoir. 165 refs., 44 figs., 1 table

  10. Radioisotope tracer study in a sludge hygienization research irradiator (SHRI).

    Science.gov (United States)

    Pant, H J; Thýn, J; Zitný, R; Bhatt, B C

    2001-01-01

    A radioisotope tracer study has been carried out in a batch type sludge hygienization research irradiator with flow from top to bottom, the objective being to measure flow rate, circulation and mixing times and to investigate the hydrodynamic behaviour of the irradiator for identifying the cause(s) of malfunction. A stimulus-response technique with NH4(82)Br as a tracer was used to measure the above parameters. Experiments were carried out at three different flow rates, i.e 1.0, 0.64 and 0.33 m3/min. Three combined models based on a set of differential equations are proposed and used to simulate the measured tracer concentration curves. The obtained parameters were used to estimate dead volume and analyse hydrodynamic behaviour of the irradiator. The nonlinear regression problem of model parameter estimation was solved using the Marquardt-Levenberg method. The measured flow rate was found to be in good agreement with the values shown by the flow meter. The circulation times were found to be half of the mixing times. A simple approach for estimation of dose based on a known vertical dose-rate profile inside the irradiator is presented. About one-fourth of the volume of the irradiator was found to be dead at lower flow rates and this decreased with increase in flow rate. At higher flow rates, a semi stagnant volume was found with slow exchange of flow between the active and dead volumes.

  11. Radioisotope tracer study in a sludge hygienization research irradiator (SHRI)

    Energy Technology Data Exchange (ETDEWEB)

    Pant, H.J. E-mail: hjpant@aspsara.barc.ernet.in; Thyn, J.; Zitny, R.; Bhatt, B.C

    2001-01-15

    A radioisotope tracer study has been carried out in a batch type sludge hygienization research irradiator with flow from top to bottom, the objective being to measure flow rate, circulation and mixing times and to investigate the hydrodynamic behaviour of the irradiator for identifying the cause(s) of malfunction. A stimulus-response technique with NH{sup 82}{sub 4}Br as a tracer was used to measure the above parameters. Experiments were carried out at three different flow rates, i.e 1.0, 0.64 and 0.33 m{sup 3}/min. Three combined models based on a set of differential equations are proposed and used to simulate the measured tracer concentration curves. The obtained parameters were used to estimate dead volume and analyse hydrodynamic behaviour of the irradiator. The nonlinear regression problem of model parameter estimation was solved using the Marquardt-Levenberg method. The measured flow rate was found to be in good agreement with the values shown by the flow meter. The circulation times were found to be half of the mixing times. A simple approach for estimation of dose based on a known vertical dose-rate profile inside the irradiator is presented. About one-fourth of the volume of the irradiator was found to be dead at lower flow rates and this decreased with increase in flow rate. At higher flow rates, a semi stagnant volume was found with slow exchange of flow between the active and dead volumes.

  12. COMPARATIVE STUDY OF TWO DYEING METHODS USING REACTIVE DYE

    OpenAIRE

    HINOJOSA Belén; MONTAVA Ignacio; BOU-BELDA Eva; Díaz, Pablo

    2016-01-01

    Environment preservation is a common worry not only for people but for companies as well. Industry is more and more concern about the necessity of developing new and more respectful processes. Dye is one of the most important processes in the textile industry but it is also considered as no too safe regarding environment issues. This process uses large amounts of water and generates big volumes of wastewater. Following this issue, new regulations and laws emerge to control the waste generate...

  13. Spectral characteristics and nonlinear studies of crystal violet dye

    Science.gov (United States)

    Sukumaran, V. Sindhu; Ramalingam, A.

    2006-03-01

    Solid-state dye-doped polymer is an attractive alternative to the conventional liquid dye solution. In this paper, the spectral characteristics and the nonlinear optical properties of the dye crystal violet are studied. The spectral characteristics of crystal violet dye doped poly(methylmethacrylate) modified with additive n-butyl acetate (nBA) are studied by recording its absorption and fluorescence spectra and the results are compared with the corresponding liquid mixture. The nonlinear refractive index of the dye in nBA and dye doped polymer film were measured using z-scan technique, by exciting with He-Ne laser. The results obtained are intercompared. Both the samples of dye crystal violet show a negative nonlinear refractive index. The origin of optical nonlinearity in the dye may be attributed due to laser-heating induced nonlinear effect.

  14. Tracer tests in geothermal resource management

    Directory of Open Access Journals (Sweden)

    Axelsson G.

    2013-05-01

    Full Text Available Geothermal reinjection involves injecting energy-depleted fluid back into geothermal systems, providing an effective mode of waste-water disposal as well as supplementary fluid recharge. Cooling of production boreholes is one of the main disadvantages associated with reinjection, however. Tracer testing is an important tool for reinjection studies because tracer tests actually have a predictive power since tracer transport is orders of magnitude faster than cold-front advancement around reinjection boreholes. A simple and efficient method of tracer test interpretation, assuming specific flow channels connecting reinjection and production boreholes, is available. It simulates tracer return profiles and estimates properties of the flow channels, which are consequently used for predicting the production borehole cooling. Numerous examples are available worldwide on the successful application of tracer tests in geothermal management, many involving the application of this interpretation technique. Tracer tests are also used for general subsurface hydrological studies in geothermal systems and for flow rate measurements in two-phase geothermal pipelines. The tracers most commonly used in geothermal applications are fluorescent dyes, chemical substances and radioactive isotopes. New temperature-resistant tracers have also been introduced and high-tech tracers are being considered.

  15. Reintegration of child soldiers in Burundi: a tracer study.

    Science.gov (United States)

    Jordans, Mark J D; Komproe, Ivan H; Tol, Wietse A; Ndayisaba, Aline; Nisabwe, Theodora; Kohrt, Brandon A

    2012-10-25

    Substantial attention and resources are aimed at the reintegration of child soldiers, yet rigorous evaluations are rare. This tracer study was conducted among former child soldiers (N=452) and never-recruited peers (N=191) who participated in an economic support program in Burundi. Socio-economic outcome indicators were measured retrospectively for the period before receiving support (T1; 2005-06); immediately afterwards (T2; 2006-07); and at present (T3; 2010). Participants also rated present functional impairment and mental health indicators. Participants reported improvement on all indicators, especially economic opportunity and social integration. At present no difference existed between both groups on any of the outcome indicators. Socio-economic functioning was negatively related with depression- and, health complaints and positively with intervention satisfaction. The present study demonstrates promising reintegration trajectories of former child soldiers after participating in a support program.

  16. Reintegration of child soldiers in Burundi: a tracer study

    Directory of Open Access Journals (Sweden)

    Jordans Mark JD

    2012-10-01

    Full Text Available Abstract Background Substantial attention and resources are aimed at the reintegration of child soldiers, yet rigorous evaluations are rare. Methods This tracer study was conducted among former child soldiers (N=452 and never-recruited peers (N=191 who participated in an economic support program in Burundi. Socio-economic outcome indicators were measured retrospectively for the period before receiving support (T1; 2005–06; immediately afterwards (T2; 2006–07; and at present (T3; 2010. Participants also rated present functional impairment and mental health indicators. Results Participants reported improvement on all indicators, especially economic opportunity and social integration. At present no difference existed between both groups on any of the outcome indicators. Socio-economic functioning was negatively related with depression- and, health complaints and positively with intervention satisfaction. Conclusion The present study demonstrates promising reintegration trajectories of former child soldiers after participating in a support program.

  17. Reintegration of child soldiers in Burundi: a tracer study

    Science.gov (United States)

    2012-01-01

    Background Substantial attention and resources are aimed at the reintegration of child soldiers, yet rigorous evaluations are rare. Methods This tracer study was conducted among former child soldiers (N=452) and never-recruited peers (N=191) who participated in an economic support program in Burundi. Socio-economic outcome indicators were measured retrospectively for the period before receiving support (T1; 2005–06); immediately afterwards (T2; 2006–07); and at present (T3; 2010). Participants also rated present functional impairment and mental health indicators. Results Participants reported improvement on all indicators, especially economic opportunity and social integration. At present no difference existed between both groups on any of the outcome indicators. Socio-economic functioning was negatively related with depression- and, health complaints and positively with intervention satisfaction. Conclusion The present study demonstrates promising reintegration trajectories of former child soldiers after participating in a support program. PMID:23095403

  18. Groundwater surface water interaction study using natural isotopes tracer

    Science.gov (United States)

    Yoon, Yoon Yeol; Kim, Yong Chul; Cho, Soo Young; Lee, Kil Yong

    2015-04-01

    Tritium and stable isotopes are a component of the water molecule, they are the most conservative tracer for groundwater study. And also, radon is natural radioactive nuclide and well dissolved in groundwater. Therefore, these isotopes are used natural tracer for the study of surface water and groundwater interaction of water curtain greenhouse area. The study area used groundwater as a water curtain for warming tool of greenhouse during the winter, and is associated with issues of groundwater shortage while being subject to groundwater-river water interaction. During the winter time, these interactions were studied by using Rn-222, stable isotopes and H-3. These interaction was monitored in multi depth well and linear direction well of groundwater flow. And dam effect was also compared. Samples were collected monthly from October 2013 to April 2014. Radon and tritium were analyzed using Quantulus low background liquid scintillation counter and stable isotopes were analyzed using an IRIS (Isotope Ratio Infrared Spectroscopy ; L2120-i, Picarro). During the winter time, radon concentration was varied from 0.07 Bq/L to 8.9 Bq/L and different interaction was showed between dam. Surface water intrusion was severe at February and restored April when greenhouse warming was ended. The stable isotope results showed different trend with depth and ranged from -9.16 ‰ to -7.24 ‰ for δ 18O value, while the δD value was ranged from -57.86 ‰ to -50.98 ‰. The groundwater age as dated by H-3 was ranged 0.23 Bq/L - 0.59 Bq/L with an average value of 0.37 Bq/L.

  19. Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site Characterization Study; Progress report, June 1--December 31, 1990

    Energy Technology Data Exchange (ETDEWEB)

    Stetzenbach, K.J.

    1990-12-31

    Ground water tracers are solutes dissolved in or carried by ground water to delineate flow pathways. Tracers provide information on direction and speed of water movement and that of contaminants that might be conveyed by the water. Tracers can also be used to measure effective porosity, hydraulic conductivity, dispersivity and solute distribution coefficients. For most applications tracers should be conservative, that is, move at the same rate as the water and not sorb to aquifer materials. Tracers must have a number of properties to be functional. Regardless of the desired properties, the chemical and physical behavior of a tracer in ground water and the porous medium under study must be understood. Good estimates of tracer behavior can be obtained from laboratory studies. Studies in this proposal will address tracer properties with analytical method development, static sorption and degradation studies and column transport studies, Mutagenicity tests will be performed on promising candidates. The tracers that will be used for these experiments are fluorinated organic acids and other organic compounds that have the chemical and biological stability necessary to be effective in the Yucca Mountain environment. Special emphasis will be placed on compounds that fluoresce or have very large ultraviolet absorption coefficients for very high analytical sensitivity.

  20. A parameter identifiability study of two chalk tracer tests

    Directory of Open Access Journals (Sweden)

    S. A. Mathias

    2006-08-01

    Full Text Available As with most fractured rock formations, Chalk is highly heterogeneous. Therefore, meaningful estimates of model parameters must be obtained at a scale comparable with the process of concern. These are frequently obtained by calibrating an appropriate model to observed concentration-time data from radially convergent tracer tests (RCTT. Arguably, an appropriate model should consider radially convergent dispersion (RCD and Fickian matrix diffusion. Such a model requires the estimation of at least four parameters. A question arises as to whether or not this level of model complexity is supported by the information contained within the calibration data. Generally modellers have not answered this question due to the calibration techniques employed. A dual-porosity model with RCD was calibrated to two tracer test datasets from different UK Chalk aquifers. A multivariate sensitivity analysis, which assumed only a priori upper and lower bounds for each model parameter, was undertaken. Rather than looking at measures of uncertainty, the shape of the multivariate objective function surface was used to determine whether a parameter was identifiable. Non-identifiable parameters were then removed and the procedure was repeated until all remaining parameters were identifiable.

    It was found that the single fracture model (SFM (which ignores mechanical dispersion obtained the best mass recovery, excellent model performance and best parameter identifiability in both the tests studied. However, there was no objective evidence suggesting that mechanical dispersion was negligible. Moreover, the SFM (with just two parameters was found to be good at approximating the Single Fracture Dispersion Model SFDM (with three parameters when different, and potentially erroneous parameters, were used. Overall, this study emphasises the importance of adequate temporal sampling of breakthrough curve data prior to peak concentrations, to ensure adequate characterisation of

  1. Study of Novel Oligomeric Azo Dyes

    Directory of Open Access Journals (Sweden)

    Patel J. R.

    2012-08-01

    Full Text Available Diazotization of p-anisidine and coupling with 3-amino-phenol-Formaldehyde (APF resin give oligomaric azo dye TAPF, based on 3-amino-phenol-Formaldehyde (APF polymer. The TAPF was then treated with 5-chloro methyl-8-quinolinol hydrochloride in the presence of a THF in alkaline medium (pH 9-10 at room temperature for 7 hrs. The resultant oligomaric ligand designated as azo polyphenol-formaldehyde-5-chloromethyl-8-quinolinol (AAPFQ was characterized by elemental analysis, IR spectral studies, and thermogravimetry. The polymeric metal chelates of AAPFQ with Cu2+, Zn2+, Mn2+, Ni2+, Fe3+ and Co2+ metal ions were prepared and characterised by metal:ligand ratio, IR and reflectance studies, magnetic properties and thermogravimetry. The AAPFQ sample was also screened for its chelating and ion-exchanging properties. Batch equilibration method has been adopted for evolution of ion-exchange properties.

  2. STUDY OF DYE-SENSITIZED SYSTEMS FOR PHOTOIMAGING

    Institute of Scientific and Technical Information of China (English)

    Fang Gao; Chun-ying Zhao; Yong-yuan Yang; Li-dong Li

    2001-01-01

    o-Chloro-hexaarylbiimidazole (o-C1-HABI) can be sensitized efficiently by cyanine dyes, the cyclopentanone and cyclohexanone dyes, when exposed to xenon lamp (use filter cut λ _< 400 nm). The photoreaction between the photoinitiator and the dyes was completed through an electron transfer process. Excellent results have been obtained in photoimaging studies, e.g. the resolution of the image can reach 7 μm. The influence of the content of the dyes and the heat after the exposure on the resolution of the image was investigated.

  3. Assessment of different dyes used in leakage studies.

    Science.gov (United States)

    Mente, Johannes; Ferk, Stephan; Dreyhaupt, Jens; Deckert, Andreas; Legner, Milos; Staehle, Hans Joerg

    2010-06-01

    The goal of this in vitro study was to identify the most suitable dye for endodontic dye leakage studies, which could be a further step towards standardisation. The root canals of 70 extracted, single-rooted human adult teeth were enlarged to apical size 50 using hand instruments. The teeth were divided into seven groups (n = 10 each), and all root canals were completely filled by injection with one of the following dyes: methylene blue 0.5% and 5%, blue ink, black ink, eosin 5%, basic fuchsin 0.5% and drawing ink. Transverse root sections from the coronal, middle and apical part of the roots were examined, and the percentage of the dentine penetrated by dye was evaluated by software-supported light microscopy. In addition, the range of particle size of drawing ink particles was evaluated. There were conspicuous differences in the relative dye penetration into the root dentine and the penetration behaviour in the different root sections (two-way ANOVA, both p < 0.0001). One dye (drawing ink) penetrated less into the root dentine compared with all the others (p <0.0001). The particle size of this agent (0.1-2 microm) corresponds best with the size range of a representative selection of 21 species of pathogenic endodontic bacteria. Compared to the other dyes tested, drawing ink appears to be superior for use in endodontic dye leakage studies. The penetration behaviour into the root dentine of all the other dyes tested might be one factor that limits the applicability of these dyes in dye leakage studies.

  4. Can silicon substituted metal-free organic dyes achieve better efficiency compared to silicon free organic dyes? A computational study.

    Science.gov (United States)

    Biswas, Abul Kalam; Das, Amitava; Ganguly, Bishwajit

    2015-12-14

    The power conversion efficiency of metal-free organic dyes in dye-sensitized solar cells (DSSCs) is now comparable to ruthenium-based polypyridyl and zinc-based porphyrin dyes. We have computationally investigated the structural, electronic and optical properties of a series of metal free organic dyes and their corresponding silicon substituted dyes. The DFT and TD-DFT calculations revealed that silicon substituted organic dyes have higher efficiency than the corresponding silicon free organic dyes. The computational results showed that the presence of silole units as a spacer group can significantly affect the performance of DSSCs compared to typically using thiophene as a spacer unit. These results corroborate the experimental observations reported in the literature. The time-dependent density functional theory (TDDFT) calculations performed at the CPCM–CAM-B3LYP/6-31+G* level of theory showed better agreement with the experimental absorption spectra of some reported metal free organic dyes having silole in the spacer group compared to other functionals and are employed in this study. Indoline donor based dye 5 showed a much shorter absorption spectrum (absorption peak at 425 nm) and smaller electron injection driving force (ΔGinjection = -1.77 eV) than the corresponding dye 8 containing silicon substituted indoline as a donor and a silole group as a spacer unit. λmax = 502 nm and ΔGinjection = -1.82 eV calculated for dye 8 are much larger than the corresponding silicon free dye 5. The silicon based dye 8 helps in achieving a much lower ΔGregeneration value than 5, which can facilitate the faster electron injection rate from the dye to the semiconductor TiO2. Dye 8 should also have a higher Voc value compared to other dyes (5-7) due to favourable interaction with the electrolyte (I(-)/I3(-)). The higher planarity and better conjugation in dye 8 facilitate the transfer of electrons from the dye molecules to the semiconductor TiO2. The calculations performed

  5. PENGEMBANGAN SISTEM TRACER STUDY ONLINE BERBASIS WEBSITE DI STMIK AMIKOM YOGYAKARTA

    Directory of Open Access Journals (Sweden)

    Alfie Nur Rahmi

    2014-06-01

    Full Text Available Tracer study is a mechanism that is performed by various parties to keep track of alumni in order to measure the relevance of the purpose and process of education with the current condition of the alumni. In addition, the results of a tracer study was also used as a condition of completeness of accreditation by Badan Akreditasi Nasional Perguruan Tinggi (BAN - PT . Tracer studies can be done in 2 ways , namely tracer manually and online. STMIK AMIKOM Yogyakarta is one of the colleges that have done online with tracer studies utilizing tracer system online at the alumni web pages since 2010. Yet in reality, the system utilization online tracer deemed not optimal in terms of both alumni and the AMIKOM . Based on the analysis of the old system using PIECES analysis, showed some problems and flaws in the old system . The results of this study are expected to prototype a new system able to answer the problems and deficiencies in the old system so that it can optimize the function and use of the online tracer system by the alumni and the AMIKOM.

  6. Spectral and nonlinear studies of night blue dye

    Science.gov (United States)

    Sindhu Sukumaran, V.; Ramalingam, A.

    2006-12-01

    Solid-state dye-doped polymer is an attractive alternative to the conventional liquid dye solution. In this Letter the spectral characteristics and the nonlinear optical properties of the dye night blue are studied. The spectral characteristics of night blue dye doped poly(methylmethacrylate) modified with additive n-butyl acetate (nBA) are studied by recording its absorption and fluorescence spectra and the results are compared with the corresponding liquid mixture. The nonlinear refractive index of the dye in nBA and dye doped polymer film were measured using z-scan technique [S.-B., Mansoor, A.A. Said, T.-H. Wei, D.J. Hagan, E.W. Van Stryland, IEEE J. Quantum Electron. 26 (1990) 760], by exciting with He Ne laser. The results obtained are intercompared. Both the samples of dye night blue show a negative nonlinear refractive index. The origin of optical nonlinearity in the dye may be attributed due to laser-heating induced nonlinear effect.

  7. Simultaneous Analyses and Applications of Multiple Fluorobenzoate and Halide Tracers in Hydrologic Studies

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Moran, J E

    2004-01-22

    An analytical method that employs ion chromatography has been developed to more fully exploit the use of fluorobenzoic acids (FBAs) and halides as hydrologic tracers. In a single run, this reliable, sensitive, and robust method can simultaneously separate and quantify halides (fluoride, chloride, bromide, and iodide) and up to seven FBAs from other common groundwater constituents (e.g., nitrate and sulfate). The usefulness of this ion chromatographic (IC) analytical method is demonstrated in both field and laboratory tracer experiments. Field experiments in unsaturated tuff featuring fractures or a fault show that this efficient and cost-effective method helps achieve the objectives of tracer studies that use multiple FBAs and/or diffusivity tracers (simultaneous use of one or more FBA and halide). The field study examines the hydrologic response of fractures and the matrix to different flow rates and the contribution of matrix diffusion in chemical transport. Laboratory tracer experiments with eight geologic media from across the United States--mostly from Department of Energy facilities where groundwater contamination is prevalent and where subsurface characterization employing tracers has been ongoing or is in need--reveal several insights about tracer transport behavior: (1) Bromide and FBAs are not always transported conservatively. (2) The delayed transport of these anionic tracers is likely related to geologic media characteristics, such as organic matter, pH, iron oxide content, and clay mineralogy. (3) Any use of iodine as a hydrologic tracer should take into account the different sorption behaviors of iodide and iodate and the possible conversion of iodine's initial chemical form. (4) The transport behavior of potential FBA and halide tracers under relevant geochemical conditions should be evaluated before beginning ambitious, large-scale field tracer experiments.

  8. Simultaneous Analyses and Applications of Multiple Fluorobenzoate and Halide Tracers in Hydrologic Studies

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Moran, J E

    2004-01-22

    An analytical method that employs ion chromatography has been developed to more fully exploit the use of fluorobenzoic acids (FBAs) and halides as hydrologic tracers. In a single run, this reliable, sensitive, and robust method can simultaneously separate and quantify halides (fluoride, chloride, bromide, and iodide) and up to seven FBAs from other common groundwater constituents (e.g., nitrate and sulfate). The usefulness of this ion chromatographic (IC) analytical method is demonstrated in both field and laboratory tracer experiments. Field experiments in unsaturated tuff featuring fractures or a fault show that this efficient and cost-effective method helps achieve the objectives of tracer studies that use multiple FBAs and/or diffusivity tracers (simultaneous use of one or more FBA and halide). The field study examines the hydrologic response of fractures and the matrix to different flow rates and the contribution of matrix diffusion in chemical transport. Laboratory tracer experiments with eight geologic media from across the United States--mostly from Department of Energy facilities where groundwater contamination is prevalent and where subsurface characterization employing tracers has been ongoing or is in need--reveal several insights about tracer transport behavior: (1) Bromide and FBAs are not always transported conservatively. (2) The delayed transport of these anionic tracers is likely related to geologic media characteristics, such as organic matter, pH, iron oxide content, and clay mineralogy. (3) Any use of iodine as a hydrologic tracer should take into account the different sorption behaviors of iodide and iodate and the possible conversion of iodine's initial chemical form. (4) The transport behavior of potential FBA and halide tracers under relevant geochemical conditions should be evaluated before beginning ambitious, large-scale field tracer experiments.

  9. Project definition study for the National Biomedical Tracer Facility

    Energy Technology Data Exchange (ETDEWEB)

    Roozen, K.

    1995-02-15

    The University of Alabama at Birmingham (UAB) has conducted a study of the proposed National Biomedical Tracer Facility (NBTF). In collaboration with General Atomics, RUST International, Coleman Research Corporation (CRC), IsoMed, Ernst and Young and the advisory committees, they have examined the issues relevant to the NBTF in terms of facility design, operating philosophy, and a business plan. They have utilized resources within UAB, CRC and Chem-Nuclear to develop recommendations on environmental, safety and health issues. The Institute of Medicine Panel`s Report on Isotopes for Medicine and the Life Sciences took the results of prior workshops further in developing recommendations for the mission of the NBTF. The IOM panel recommends that the NBTF accelerator have the capacity to accelerate protons to 80 MeV and a minimum of 750 microamperes of current. The panel declined to recommend a cyclotron or a linac. They emphasized a clear focus on research and development for isotope production including target design, separation chemistry and generator development. The facility needs to emphasize education and training in its mission. The facility must focus on radionuclide production for the research and clinical communities. The formation of a public-private partnership resembling the TRIUMF-Nordion model was encouraged. An advisory panel should assist with the NBTF operations and prioritization.

  10. Bromide as a tracer for studying water movement and nitrate displacement in soils: comparison with stable isotope tracers; Bromid als Tracer zur Untersuchung der Wasserbewegung und der Nitratverlagerung in Boeden: Vergleich mit stabilisotopen Tracern

    Energy Technology Data Exchange (ETDEWEB)

    Russow, R.; Knappe, S. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Bad Lauchstaedt (Germany). Sektion Bodenforschung

    1999-02-01

    Tracers are an ideal means of studying water movement and associated nitrate displacement. Often bromide is preferred as a tracer because it is considered a representative tracer for water and because, being a conservative tracer (i.e. not involved in chemical and biological soil processes), it can be used for studying anion transport in soils. Moreover, it is less expensive and easier to measure than the stable isotopes deuterium and {sup 15}N. Its great advantage over radioactive tracers (e.g. tritium), which outweighs their extreme sensitivity and ease of measurement and which it has in common with stable isotopes, is that it does not require radiation protection measures. However, there are also constraints on the use of bromide as a tracer in soil/water/plant systems. Our own studies on different soils using D{sub 2}O, bromide and [{sup 15}N]-nitrate in lysimeters suggest that the above assumptions on bromide tracers need not always be valid under conditions as they prevail in biologically active soils. As the present paper shows, these studies permit a good assessment of the possibilities and limits to these tracers. [Deutsch] Fuer die Untersuchung der Wasserbewegung sowie der daran gekoppelten Nitrat-Verlagerung ist der Einsatz von Tracern das Mittel der Wahl. Dabei wird Bromid als Tracer haeufig bevorzugt, da es allgemein als ein repraesentativer Tracer fuer Wasser und als konservativer Tracer (nicht involviert in chemische und biologische Bodenprozesse) zur Untersuchung des Anionentransportes in Boeden angesehen wird und es gegenueber den stabilen Isotopen Deuterium und {sup 15}N billiger und einfacher zu bestimmen ist. Gegenueber den radioaktiven Tracern (z.B. Tritium), die zwar sehr empfindlich und einfach messbar sind, besteht der grosse Vorteil, dass, wie bei den stabilen Isotopen, keine Strahlenschutzmassnahmen ergriffen werden muessen. Es gibt jedoch auch einschraenkende Hinweise fuer die Verwendung von Bromid als Tracer im System Boden

  11. Colorimetric studies of some newly synthesized bisazo reactive dyes

    Directory of Open Access Journals (Sweden)

    Divyesh R. Patel

    2016-09-01

    Full Text Available A series of cold brand bisazo reactive dyes (4a–h were obtained by the coupling of tetrazotised 4,4′-methylene-bis(2-methyl-5-nitro aniline (2 with various cyanurated coupling components (3a–h in good yield. Their dyeing performances as reactive dyes have been assessed on silk, wool and cotton fabrics. These dyes were characterized by UV–Vis, FTIR, 1H NMR spectroscopic techniques elemental analysis. The percentage dye bath exhaustion and fixation on different fibers were found to be very good. The dyed fabric showed moderate to very good light fastness and good to excellent washing and rubbing fastness properties. Spectral properties and colorimetric data (L∗, a∗, b∗, C∗, H∗, K/S have also been studied in detail.

  12. Environmental Tracers

    Directory of Open Access Journals (Sweden)

    Trevor Elliot

    2014-10-01

    Full Text Available Environmental tracers continue to provide an important tool for understanding the source, flow and mixing dynamics of water resource systems through their imprint on the system or their sensitivity to alteration within it. However, 60 years or so after the first isotopic tracer studies were applied to hydrology, the use of isotopes and other environmental tracers are still not routinely necessarily applied in hydrogeological and water resources investigations where appropriate. There is therefore a continuing need to promote their use for developing sustainable management policies for the protection of water resources and the aquatic environment. This Special Issue focuses on the robustness or fitness-for-purpose of the application and use of environmental tracers in addressing problems and opportunities scientifically, to promote their wider use and to address substantive issues of vulnerability, sustainability, and uncertainty in (groundwater resources systems and their management.

  13. Study on Radioecology and Tracer of Iodine-129

    Energy Technology Data Exchange (ETDEWEB)

    Xiaolin, Hou [Riso National Laboratory, NUK, DK, Roskilde (Denmark)

    2004-07-01

    Iodine-129 (15.7 Ma) is a naturally occurring radioisotope of iodine. The ratio of {sup 129}I/{sup 127}I was estimated to be {approx} 10{sup -12} in the ocean and 10{sup -11} in the territorial environment in pre-nuclear era, releases from nuclear weapon tests have increased this ratio to {approx} 10{sup -10}. However, a large amount of iodine-129 was released from various nuclear facilities, and the greatest releases of {sup 129}I are from two European reprocessing plants, especially in recent years. By 1998, 2600 Kg and 220 Kg {sup 129}I have been discharged to the marine environment and atmosphere from La Hague (France) and Sellafield reprocessing plants, respectively. This amount is tens times larger than the total {sup 129}I inventory in the pre-nuclear ocean and weapon test releases. Although there is no significant radiation risk for the human health at present level of {sup 129}I, the continuously increasing production and release of {sup 129}I make the accumulation of {sup 129}I in the environment, immigration, cycle and long term radioecological risk should be give more attention due to its long half-life, high accumulation in human thyroid and high mobility. Iodine is a conservative element in the ocean, the large amount of iodine-129 discharged to the marine system can therefore be used as a oceanographic tracer to study the physical dispersion, mixing and circulative processes of water mass in the ocean. In Riso national laboratory, a radiochemical neutron activation analysis method was developed, using this method the radioecology and tracer of iodine-129 was studied. Some representative works are presented below. (1) Evaluation of radiation exposure of humans to iodine-129. The human and animal thyroids collected from different places, such as Tianjin in China, Gemol in Belarus, Ribe in Denmark, human urine in Denmark, seafood in China were analysed for iodine-129 concentration and {sup 129}I/{sup 127}I ratio, the exposure level were compared with

  14. Artificial ultra-fine aerosol tracers for highway transect studies

    Science.gov (United States)

    Cahill, Thomas A.; Barnes, David E.; Wuest, Leann; Gribble, David; Buscho, David; Miller, Roger S.; De la Croix, Camille

    2016-07-01

    The persistent evidence of health impacts of roadway aerosols requires extensive information for urban planning to avoid putting populations at risk, especially in-fill projects. The required information must cover both highway aerosol sources as well as transport into residential areas under a variety of roadway configurations, traffic conditions, downwind vegetation, and meteorology. Such studies are difficult and expensive to do, but were easier in the past when there was a robust fine aerosol tracer uniquely tied to traffic - lead. In this report we propose and test a modern alternative, highway safety flare aerosols. Roadway safety flares on vehicles in traffic can provide very fine and ultra-fine aerosols of unique composition that can be detected quantitatively far downwind of roadways due to a lack of upwind interferences. The collection method uses inexpensive portable aerosol collection hardware and x-ray analysis protocols. The time required for each transect is typically 1 h. Side by side tests showed precision at ± 4%. We have evaluated this technique both by aerosol removal in vegetation in a wind tunnel and by tracking aerosols downwind of freeways as a function of season, highway configuration and vegetation coverage. The results show that sound walls for at-grade freeways cause freeway pollution to extend much farther downwind than standard models predict. The elevated or fill section freeway on a berm projected essentially undiluted roadway aerosols at distances well beyond 325 m, deep into residential neighborhoods. Canopy vegetation with roughly 70% cover reduced very fine and ultra-fine aerosols by up to a factor of 2 at distances up to 200 m downwind.

  15. Column studies for biosorption of dyes from aqueous solutions on ...

    African Journals Online (AJOL)

    Abstract. Biosorption is becoming a promising alternative to replace or ... biomass was immobilised in a polysulphone matrix in the form of spherical beads. In column studies, adsorption and elution tests were conducted for each dye and the ...

  16. A comparative study of polymer-dye interaction

    Directory of Open Access Journals (Sweden)

    Nandini R.

    2009-08-01

    Full Text Available The interaction between an anionic dye Methyl Orange and two poly cations namely, Poly (N-vinyl-4-methylpyridiniumiodide, (PC1 & Poly (vinylbenzyltriphenylphosphoniumchloride, (PC2 has been investigated by spectrophotometric method. The polymers are observed to induce metachromasy in the dye as evidenced from the considerable blue shift in the absorption maximum of the dye. The interaction constant and thermodynamic parameters of interaction have been determined by absorbance measurements at the metachromatic band. The effect of additives such as ionic salts, alcohols, urea and polyelectrolytes on the reversal of metachromasy has been studied and used to determine the stability of the metachromatic complex and to understand the nature of binding.

  17. A comparative study of non-covalent encapsulation methods for organic dyes into silica nanoparticles

    Directory of Open Access Journals (Sweden)

    Auger Aurélien

    2011-01-01

    Full Text Available Abstract Numerous luminophores may be encapsulated into silica nanoparticles (< 100 nm using the reverse microemulsion process. Nevertheless, the behaviour and effect of such luminescent molecules appear to have been much less studied and may possibly prevent the encapsulation process from occurring. Such nanospheres represent attractive nanoplatforms for the development of biotargeted biocompatible luminescent tracers. Physical and chemical properties of the encapsulated molecules may be affected by the nanomatrix. This study examines the synthesis of different types of dispersed silica nanoparticles, the ability of the selected luminophores towards incorporation into the silica matrix of those nanoobjects as well as the photophysical properties of the produced dye-doped silica nanoparticles. The nanoparticles present mean diameters between 40 and 60 nm as shown by TEM analysis. Mainly, the photophysical characteristics of the dyes are retained upon their encapsulation into the silica matrix, leading to fluorescent silica nanoparticles. This feature article surveys recent research progress on the fabrication strategies of these dye-doped silica nanoparticles.

  18. Studies on Dyeing Process Variables for Salt Free Reactive Dyeing of Glycine Modified Cationized Cotton Muslin Fabric

    Science.gov (United States)

    Samanta, Ashis Kumar; Kar, Tapas Ranjan; Mukhopadhyay, Asis; Shome, Debashis; Konar, Adwaita

    2015-04-01

    Bleached cotton muslin fabric with or without pre-oxidized with NaIO4 (oxy-cotton) was chemically modified with glycine (amino acid) by pad dry calendar process to investigate the changes in textile properties and its dyeability with reactive dye. This glycine modified cotton incorporates new functional groups producing -NH3 + or -C=NH+ -ion (cationic groups) in acid bath to obtain cationized cotton making it amenable to a newer route of salt free reactive dyeing in acid bath. In the present work the process variables of reactive dyeing in the salt free acid bath for dyeing of amine (glycine) modified cationized cotton were studied and optimized. The present study also includes thorough investigation of changes in important textile related properties and dyeability with reactive dye after such chemical modifications. Between oxidized and unoxidized cotton muslin fabric, unoxidized cotton fabric shows better reactive dye uptake in both conventional alkaline bath dyeing and nonconventional salt free acid bath dyeing particularly for high exhaustion class of reactive dye with acceptable level of colour fastness and overall balance of other textile related properties. Moreover, application of dye fixing agent further improves surface colour depth (K/S) of the glycine treated cotton fabric for HE brand of reactive dyes. Corresponding reaction mechanisms for such modifications were supported by FTIR spectroscopy. Finally unoxidized cotton and pre-oxidized cotton further treated with glycine (amino acid) provide a new route of acid bath salt free reactive dyeing showing much higher dye uptake and higher degree of surface cover with amino acid residue anchored to modified cotton.

  19. Spectrophotometric and spectrofluorimetric studies of novel heterocyclic Schiff base dyes

    Directory of Open Access Journals (Sweden)

    Hadi M. Marwani

    2014-11-01

    Full Text Available Novel heterocyclic Schiff base dyes were prepared by the reaction of salicylaldehyde/2-Hydroxy-1-naphthaldehyde with different heterocyclic amines. Results of the newly synthesized compounds established by FT-IR, 1H-NMR, 13C-NMR and GC–MS spectroscopic experiments were consistent with their chemical structures. Resulted heterocyclic Schiff base dyes were found to be pure from data obtained by the elemental analysis. In addition, spectrophotometric and spectrofluorimetric studies showed that these dyes were good absorbent and fluorescent. Fluorescence polarity study data revealed that some of these compounds were sensitive to the polarity of the microenvironment provided by different solvents. Time-based fluorescence steady-state measurements also showed that these heterocyclic Schiff base dyes have high photostability against photobleaching.

  20. Spectrophotometric and spectrofluorimetric studies of novel heterocyclic Schiff base dyes

    OpenAIRE

    2014-01-01

    Novel heterocyclic Schiff base dyes were prepared by the reaction of salicylaldehyde/2-Hydroxy-1-naphthaldehyde with different heterocyclic amines. Results of the newly synthesized compounds established by FT-IR, 1H-NMR, 13C-NMR and GC–MS spectroscopic experiments were consistent with their chemical structures. Resulted heterocyclic Schiff base dyes were found to be pure from data obtained by the elemental analysis. In addition, spectrophotometric and spectrofluorimetric studies showed that t...

  1. Natural dye extracted from karkadah and its application in dye-sensitized solar cells: experimental and density functional theory study.

    Science.gov (United States)

    Reda, S M; Soliman, K A

    2016-02-01

    This work presents an experimental and theoretical study of cyanidin natural dye as a sensitizer for ZnO dye-sensitized solar cells. ZnO nanoparticles were prepared using ammonia and oxalic acid as a capping agent. The calculated average size of the synthesized ZnO with different capping agents was found to be 32.1 nm. Electronic properties of cyanidin and delphinidin dye were studied using density functional theory (DFT) and time-dependent DFT with a B3LYP/6-31G(d,p) level. By comparing the theoretical results with the experimental data, the cyanidin dye can be used as a sensitizer in dye-sensitized solar cells. An efficiency of 0.006% under an AM-1.5 illumination at 100  mW/cm(2) was attained. The influence of dye adsorption time on the solar cell performance is discussed.

  2. A spectroscopic study of interaction of cationic dyes with heparin

    Directory of Open Access Journals (Sweden)

    R. Nandini

    2010-01-01

    Full Text Available The interaction of two cationic dyes namely, acridine orange and pinacyanol chloride with an anionic polyelectrolyte, heparin, has been investigated by spectrophotometric method.The polymer induced metachromasy in the dyes resulting in the shift of the absorption maxima of the dyes towards shorter wavelengths. The stability of the complexes formed between acridine orange and heparin was found to be lesser than that formed between pinacyanol chloride and heparin. This fact was further confirmed by reversal studies using alcohols, urea and surfactants. The interaction of acridine orange with heparin has also been investigated fluorimetrically.The interaction parameters revealed that binding between acridine orange and heparin arises due to electrostatic interaction while that between pinacyanol chloride and heparin is found to involve both electrostatic and hydrophobic forces. The effect of the structure of the dye in inducing metachromasy has also been discussed.

  3. Air pollution tracer studies in the lower atmosphere. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    The bibliography contains citations concerning the use of tracers to study lower atmospheric air pollution movements. Citations discuss project descriptions and results, techniques, and tracer materials. Tracer movement from nuclear power plants, industrial stacks, and urban areas is discussed. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  4. Molecular design of donor-acceptor dyes for efficient dye-sensitized solar cells I: a DFT study.

    Science.gov (United States)

    El-Shishtawy, Reda M; Asiri, Abdullah M; Aziz, Saadullah G; Elroby, Shaaban A K

    2014-06-01

    Dye-sensitized solar cells (DSSCs) have drawn great attention as low cost and high performance alternatives to conventional photovoltaic devices. The molecular design presented in this work is based on the use of pyran type dyes as donor based on frontier molecular orbitals (FMO) and theoretical UV-visible spectra in combination with squaraine type dyes as an acceptor. Density functional theory has been used to investigate several derivatives of pyran type dyes for a better dye design based on optimization of absorption, regeneration, and recombination processes in gas phase. The frontier molecular orbital (FMO) of the HOMO and LUMO energy levels plays an important role in the efficiency of DSSCs. These energies contribute to the generation of exciton, charge transfer, dissociation and exciton recombination. The computations of the geometries and electronic structures for the predicted dyes were performed using the B3LYP/6-31+G** level of theory. The FMO energies (EHOMO, ELUMO) of the studied dyes are calculated and analyzed in the terms of the UV-visible absorption spectra, which have been examined using time-dependent density functional theory (TD-DFT) techniques. This study examined absorption properties of pyran based on theoretical UV-visible absorption spectra, with comparisons between TD-DFT using B3LYP, PBE, and TPSSH functionals with 6-31+G (d) and 6-311++G** basis sets. The results provide a valuable guide for the design of donor-acceptor (D-A) dyes with high molar absorptivity and current conversion in DSSCs. The theoretical results indicated 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran dye (D2-Me) can be effectively used as a donor dye for DSSCs. This dye has a low energy gap by itself and a high energy gap with squaraine acceptor type dye, the design that reduces the recombination and improves the photocurrent generation in solar cell.

  5. Glass mixing theory and tracer study results from the SF-10 run

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, B.W.; Routt, K.R.

    1988-08-01

    A general, partial differential equation governing glass mixing in the Slurry Fed Ceramic Melter (SFCM) was derived and a solution obtained based upon certain simplifying assumptions. Tracer studies were then conducted in the SFCM during the SF-10 run to test the theory and characterize glass mixing in this melter. Analysis of the tracer data shows that glass mixing in the SFCM can be explained by use of a model of two, well-mixed tanks in series.

  6. First-principles study of Carbz-PAHTDDT dye sensitizer and two Carbz-derived dyes for dye sensitized solar cells

    CERN Document Server

    Mohammadi, Narges

    2014-01-01

    Two new carbazole-based organic dye sensitizers are designed and investigated in silico. These dyes are designed through chemical modifications of the conjugated bridge of a reference organic sensitizer known as Carbz-PAHTDDT (S9) dye. The aim of designing these dyes was to reduce the energy gap between their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and to red-shift their absorption response compared to those of the reference S9 dye sensitizer. This reference dye has a reported promising efficiency when coupled with ferrocene-based electrolyte composition. To investigate geometric and electronic structure, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were conducted on the new dyes as well as the reference dye. The present study indicated that the long-range correction to the theoretical model in the TD-DFT simulation is important to produce accurate absorption wavelengths.The theoretical studies have shown a reduced HOMO-LUMO gap ...

  7. Using biofuel tracers to study alternative combustion regimes

    Science.gov (United States)

    Mack, J. H.; Flowers, D. L.; Buchholz, B. A.; Dibble, R. W.

    2007-06-01

    Interest in the use of alternative fuels and engines is increasing as the price of petroleum climbs. The inherently higher efficiency of Diesel engines has led to increased adoption of Diesels in Europe, capturing approximately 40% of the new passenger car market. Unfortunately, lower CO2 emissions are countered with higher nitrogen oxides (NOx) and particulate matter (PM) emissions and higher noise. Adding oxygenated compounds to the fuel helps reduce PM emissions. However, relying on fuel alone to reduce PM is unrealistic due to economic constraints and difficult due to the emerging PM standards. Keeping peak combustion temperature below 1700 K inhibits NOx formation. Altering the combustion regime to burn at temperatures below the NOx threshold and accept a wide variety of fuels seems like a promising alternative for future engines. Homogeneous charge compression ignition (HCCI) is a possible solution. Fuel and air are well mixed prior to intake into a cylinder (homogeneous charge) and ignition occurs by compression of the fuel-air mixture by the piston. HCCI is rapid and relatively cool, producing little NOx and PM. Unfortunately, it is hard to control since HCCI is initiated by temperature and pressure instead of a spark or direct fuel injection. We investigate biofuel HCCI combustion, and use intrinsically labeled biofuels as tracers of HCCI combustion. Data from tracer experiments are used to improve our combustion modeling.

  8. Acupuncture meridians demythified. A study using the radioactive tracer method

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J.; Esquerre, J.P.; Guiraud, R.; Guiraud, G.; Lazorthes, Y.

    1988-07-01

    Radioactive trajectories can be visualized by injecting a radioactive tracer, technetium 99 m, at the site of acupuncture points. To determine the exact nature of these trajectories we performed several experiments on healthy volunteers, and our results may be summarized as follows. The target organs of technetium 99 m, and notably the thyroid gland, were always visualized. The circulating radioactivity, visible on scintiscans and confirmed by venous blood counts, was not negligible. The radioactive trajectories we observed were often divided at their starting point and did not extend along the whole length of the acupuncture meridians they might have made visible. The radioactive trajectories disappeared after venous blockade to reappear when the blockade was lifted. Finally, the radioactive trajectories obtained were very similar after injection at the acupuncture point and at a control point. These findings indicate a lymphatic and venous drainage of the radioactive tracer at the site of injection followed by transportation through the veins, rather than visualization of acupuncture meridians as suggested by some authors.

  9. Urban Dispersion Program MSG05 Field Study: Summary of Tracer and Meteorological Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Allwine, K Jerry; Flaherty, Julia E.

    2006-08-09

    The Urban Dispersion Program is a multi-year project, funded by the U.S. Department of Homeland Security, to better understand the flow and dispersion of airborne contaminants through and around the deep street canyons of New York City. The first tracer and meteorological field study was a limited study conducted during March 2005 near the Madison Square Garden in midtown Manhattan. Six safe, inert, gaseous perfluorocarbon tracers were released simultaneously at five street-level locations during two experimental days. In addition to collecting tracer data, meteorological data were also collected. Brookhaven National Laboratory conducted the bulk of the tracer and meteorological field efforts with Pacific Northwest National Laboratory and Stevens Institute of Technology assisting by measuring the vertical profile of winds. The Environmental Protection Agency worked with Brookhaven National Laboratory in accomplishing the personal exposure component of the study. This report presents some results from this analysis. In general, different release locations showed vastly different plume footprints for tracer materials, and the situation was made very complex with upwind and/or crosswind transport of tracer near street-level for the different release locations. Overall wind speeds and directions upwind and over the city were generally constant throughout each of the two experimental periods.

  10. Optical study of dye-containing fluorinated polyimide thin films

    Science.gov (United States)

    Quaranta, A.; Carturan, S.; Maggioni, G.; Della Mea, G.; Ischia, M.; Campostrini, R.

    Thin films of dye-containing fluorinated polyimide have been obtained by adding the dye powder to the polyamic acid resin and by spin coating the resulting solution on silica and silicon substrates. 6FDA (4,4'-hexafluoroisopropylidene diphthalic anhydride) and DAB (diaminobenzophenone) have been used as precursor monomers and rhodamine B as dye. The influence of the rhodamine-B molecule on the completeness of the imidization process has been studied by coupled thermogravimetric and mass-spectrometric analyses (TG-MS) of pure and doped polyamic acid resin and by FT-IR analysis of samples before and after curing. Optical emission, excitation and absorption spectra have been collected in order to study spectroscopic and aggregation characteristics of rhodamine as a function of the deposition parameters.

  11. The extraction and absorption study of natural dye from Areca catechu for dye sensitized solar cell application

    Science.gov (United States)

    Najm, Asmaa Soheil; Mohamad, Abu Bakar; Ludin, Norasikin A.

    2017-05-01

    Natural dye from local plant has a potential to replace the synthetic dye due to the lower environmental impact and simple processing method. This study focus on the properties of natural dye (Betalain) from Areca catechu, extracted using different solvents, namely hexane, ethanol, acetonitrile, and methanol. Different extracting solvent were used to observe the absorption spectra by using UV-Vis absorption spectroscopy. Fourier transforms infrared (FTIR) were used to characterize the dye's active components at (4000 - 650) cm-1. From the FTIR result, the CO=OH which corresponds to the carboxylic group in betalain dye is observed. Hexane was appeared to be the best solvents according to the highest absorbance obtained from betalain. The optimum pH and temperature for extraction were also identified at pH 4.5 and 65 °C. At these conditions, the absorbance was the highest.

  12. Sulfadimethoxine transport in soil columns in relation to sorbable and non-sorbable tracers.

    Science.gov (United States)

    Park, Jong Yol; Huwe, Bernd

    2016-06-01

    In this study, miscible displacement experiment and batch sorption experiments were performed with sulfadimethoxine, dye tracer, Brilliant Blue FCF (BB) and a conservative tracer (bromide) to depict, analyse and interpret transport paths of sulfadimethoxine in undisturbed and disturbed soil columns. Batch sorption experiment revealed that sorption potential increased in the order: Brilliant Blue FCF > sulfadimethoxine > bromide. The horizontal spatial patterns of sulfadimethoxine and the tracers were analysed in each depth, and selective samples were taken in horizontal cross-section. Non-adsorbable and conservative tracer, bromide spread more widely into longitudinal and horizontal direction than sulfadimethoxine and Brilliant Blue FCF, since adsorption reduced transversal dispersion of the sulfadimethoxine and dye. In non-stained area, residual concentrations of sulfadimethoxine were relatively lower than in stained areas. Therefore, Brilliant Blue FCF distribution can be used to approximate sulfadimethoxine movement in soil. However, presence of preferential flow networks found in undisturbed soil cores can enhance mobility of sulfadimethoxine and the tracers, due to faster flow velocities and non-equilibrium adsorption. Our findings showed that other dye tracers may also be applicable to identify transport pathways of various organic contaminants, of which physico-chemical properties are similar to those of the dye tracers. Preferential flow should be considered for drinking water managements and transport modelling, since this allows faster pollutants transport from their sources, and create critical consequences for groundwater quality and solute transport modelling.

  13. COMPARATIVE STUDY OF DYEING EFFICIENCY AND RETENTION CAPACITY OF HERBAL HAIR DYES

    Directory of Open Access Journals (Sweden)

    Pingle R.P

    2013-04-01

    Full Text Available In the present investigation, attempts were made to make a powder herbal hair dye that gives dark brown to black colour to hair, resembling natural hair colour with better dyeing effect and greater retention capacity on comparison with marketed herbal hair dye formulation. Most of the marketed herbal hair dye formulations contain para-phenylenediamine at 20-25% concentrations which is the main ingredient of commercial synthetic dyes. It is known to trigger allergic skin reactions in many people. Ayurvedic powder hair dye devoid of any synthetic agent was prepared in present research work and evaluated for dyeing efficiency. Different combinations of powdered leaves, fruits of plants like Madayantika, Bhringraj, Amla and Nilini were evaluated as hair dyes. The polyherbal hair dye compositions containing large proportion of Nili, Mehendi and 5% Bhringraj and Amla, blended with 5% loha bhasma were prepared and evaluated for physicochemical parameters like particle size, colour, pH, angle of repose and bulk density. Ayurvedic polyherbal powder hair dye of present investigation is semi-permanent in nature and exhibit better dyeing efficiency than marketed herbal hair dye.

  14. Aberration corrected STEM to study an ancient hair dyeing formula

    Science.gov (United States)

    Patriarche, G.; Van Elslande, E.; Castaing, J.; Walter, P.

    2014-05-01

    Lead-based chemistry was initiated in ancient Egypt for cosmetic preparation more than 4000 years ago. Here, we study a hair-dyeing recipe using lead salts described in text since Greco-Roman times. We report direct evidence about the shape and distribution of PbS nanocrystals that form within the hair during blackening.

  15. Tracer studies of anodic films formed on aluminium in malonic and oxalic acids

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Vergara, S.J. [Corrosion and Protection Centre, School of Materials, The University of Manchester, P.O. Box 88, Manchester M60 1QD (United Kingdom)], E-mail: s.garcia-vergara@manchester.ac.uk; Skeldon, P.; Thompson, G.E. [Corrosion and Protection Centre, School of Materials, The University of Manchester, P.O. Box 88, Manchester M60 1QD (United Kingdom); Habakaki, H. [Graduate School of Engineering, Hokkaido University, N13-W8, Sapporo 060-8628 (Japan)

    2007-12-30

    Using a tungsten-containing layer, incorporated into sputtering-deposited aluminium, as a tracer, the growth of porous anodic films in malonic and oxalic acid electrolytes has been investigated using transmission electron microscopy, Rutherford backscattering spectroscopy and nuclear reaction analysis. Comparisons were also made with films formed in phosphoric acid electrolyte, which have been studied previously. The findings reveal a distortion of the tracer layer within the barrier region of the porous films, evident as a lagging of the tracer beneath the pores relative to that in the adjacent cell wall region. Further, the films are significantly thicker than the layer of metal consumed during anodizing and display smooth-sided pores. The anodizing behaviours are consistent with a major role for field-assisted flow of film material within the barrier layer in the development of the pores.

  16. Use of thorium as tracer on study of groundwater of Botucatu sandstone

    Energy Technology Data Exchange (ETDEWEB)

    Porto, Paulo Augusto d' A.; Menezes, Maria Angela B.C. de; Moreira, Rubens Martins; Reis Junior, Aluisio Souza; Kastner, Geraldo Frederico, E-mail: paap@cdtn.br, E-mail: menezes@cdtn.br, E-mail: rubens@cdtn.br, E-mail: reisas@cdtn.br, E-mail: gfk@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    Thorium in some mineral compounds is very difficult to be dissolved in aqueous medium. To study the mobility of thorium in water, one alternative is to complex this element with EDTA, becoming possible to follow the behavior of thorium this medium. This way, in groundwater with low natural radioactivity and low {sup 232}Th activity, thorium can be used as a tracer. This paper describes the application of the complex Th-EDTA as a tracer applying the solution trough a sandstone sample made by rock from Botucatu Sandstone. The objective was to simulate the flow of groundwater inside the original rock aiming at future use of rare-earth elements complexed with EDTA as tracer. Alpha spectrometry technique was used to determine {sup 232}Th in the water samples with {sup 230}Th as inner-standard. (author)

  17. Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain site characterization study. Progress report, October 1, 1994--December 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Stetzenbach, K.; Farnham, I.

    1994-12-31

    The bromide anion has been used extensively as a tracer for mapping the flow of groundwater. It has proven to be both a safe and reliable groundwater tracer. The goal in this study is to find several tracing compounds with characteristics similar to the bromide anion to be used in multiple well tracing tests. Four groups of fluorinated organic acids were selected as candidates for groundwater tracers. These groups include fluorinated benzoic acids (FBA), fluorinated salicylic acids (FSA), fluorinated toluic acids (FTA), and fluorinated cinnamic acids (FCA). These compounds have been shown to move readily with the flow of water and do not adsorb to soil. They are also non-toxic. In this study, the retention of the fluorinated organic acids on to a soil column is compared to that of the bromide ion. The time required for the elution of each analyte from the soil column is measured using a UV-Vis detector. The soils consist of the light, medium, and dark tuffs used in the batch study. The work performed during this quarter consists of the continuation of the batch studies for the fluorinated benzoic acids and column studies for several potential tracer compounds.

  18. A STUDY ON CONTACT DERMATITIS TO HAIR DYE AND HENNA

    Directory of Open Access Journals (Sweden)

    Neerja Puri

    2013-10-01

    Full Text Available P- Phenylenediamine is an oxidative chemical that is frequently used as a permanent hair-coloring agent. It is added to henna to increase the intensity and longevity of the tattoo and expedites its drying time. Henna itself is a greenish brown vegetable coloring made from the leaves of Lawsonia inermis and rarely causes allergic contact dermatitis. The addition of PPD causes the contact sensitization to black henna. Serious adverse skin reactions to permanent hair dyes and temporary black tattoos have been reported. As temporary tattoos have become fashionable among adolescents, the risk profile for p-phenylenediamine (PPD sensitization of the population has changed simultaneously with an increasing use of hair dyes in this age group. With increased popularity of body art such as body piercing and tattooing, an increase in temporary henna tattoos has also occurred. Although the appeal of non-permanence exists for henna tattoos, dermatologists have begun to see numerous cases of allergic contact dermatitis linked with a certain type of henna. We selected 50 patients using hair dye and henna for our study. Patch testing was done in all the patients using Indian standard series of antigens. Regarding to the side effects to hair dye and henna and itching was the commonest symptom seen in 16% patients, erythematous scaly plaques were seen in 10% patients, vesicular reactions were seen in 6% patients, angioneurotic oedema and contact urticaria was seen in 4% patients each and anaphylaxis and keloidal reaction was seen in 2% patients each.

  19. [Studies on percutaneous absorption of ruyi jinhuang san patcher with radioisotope tracer].

    Science.gov (United States)

    Zhao, H W; Shen, Z; Zhou, B; Lin, X; Ye, M

    1993-04-01

    Berberine is one of the active ingredients in Ruyi Jinhuang San Patcher. With 3H-berberine as the tracer, a radio-labelled method was used for determining percutaneous rate and drug concentration of berberine in plasma in vivo and in vitro. A study on the percutaneous rate of different technological plasters and various animal skins was also carried out.

  20. Technical Secondary Schools and the Labour Market: Some Results from a Tracer Study in Kenya.

    Science.gov (United States)

    Narman, Anders

    1988-01-01

    Reports tracer studies of Kenyan youths leaving technical school to determine their success at obtaining gainful employment. Almost 43% were neither in formal schooling nor training, nor employed a year after leaving, although technical skills were seen as useful, particularly in private life. (DP)

  1. A state space transformation can yield identifiable models for tracer kinetic studies with enrichment data.

    Science.gov (United States)

    Ramakrishnan, Rajasekhar; Ramakrishnan, Janak D

    2010-11-01

    Tracer studies are analyzed almost universally by multicompartmental models where the state variables are tracer amounts or activities in the different pools. The model parameters are rate constants, defined naturally by expressing fluxes as fractions of the source pools. We consider an alternative state space with tracer enrichments or specific activities as the state variables, with the rate constants redefined by expressing fluxes as fractions of the destination pools. Although the redefinition may seem unphysiological, the commonly computed fractional synthetic rate actually expresses synthetic flux as a fraction of the product mass (destination pool). We show that, for a variety of structures, provided the structure is linear and stationary, the model in the enrichment state space has fewer parameters than that in the activities state space, and is hence better both to study identifiability and to estimate parameters. The superiority of enrichment modeling is shown for structures where activity model unidentifiability is caused by multiple exit pathways; on the other hand, with a single exit pathway but with multiple untraced entry pathways, activity modeling is shown to be superior. With the present-day emphasis on mass isotopes, the tracer in human studies is often of a precursor, labeling most or all entry pathways. It is shown that for these tracer studies, models in the activities state space are always unidentifiable when there are multiple exit pathways, even if the enrichment in every pool is observed; on the other hand, the corresponding models in the enrichment state space have fewer parameters and are more often identifiable. Our results suggest that studies with labeled precursors are modeled best with enrichments.

  2. Use of tracers for mud filtrate and completion fluid invasion studies

    Energy Technology Data Exchange (ETDEWEB)

    Kleven, Reidun [Statoil DDB, Bergen (Norway); Dahl, John Blessum; Bjoernstad, Tor; Qvenild, Carsten; Tollan, Odd [Institutt for energiteknikk, Kjeller (Norway)

    1996-09-30

    The objectives of this work are (1): to study sorption/desorption of mud filtrate ions near the wellbore region by using water sampled with a formation tester equipment (FTE); (2) to study sorption/desorption of ions in the mud filtrate and the completion fluid by monitoring the ionic composition of produced water; (3) to determine the fraction of mud filtrate and completion fluid water in produced water; and (4) develop a suitable and safe tracer method. A tracer method was developed to measure sorption/desorption of various ions infiltrating the reservoir during drilling and completion of a well. Tritiated water (HTO) was used to tag the mud filtrate and bromide ion (Br{sup -}) to tag the completion fluid. The measurements are based on analysis of FTE and produced water samples. The ionic concentrations observed are compared with corresponding `no sorption/desorption` concentration values determined theoretically. Special attention is paid to the `tracer diagram` of an open well, because a `no sorption/desorption curve` can be expressed in a straight line in a linear coordinate system. Observed deviations from these curves show that sorption/desorption processes have taken place. The tracer method presented was useful to determine the distribution of ions in the pore-water/sedimentary rock system near the wellbore

  3. Field studies of transport and dispersion of atmospheric tracers in nocturnal drainage flows

    Energy Technology Data Exchange (ETDEWEB)

    Gudiksen, P.H.; Ferber, G.J.; Fowler, M.M.; Eberhard, W.L.; Fosberg, M.A.; Knuth, W.R.

    1984-01-01

    A series of tracer experiments were carried out as part of the Atmospheric Studies in Complex Terrain (ASCOT) program to evaluate pollutant transport and dispersion characteristics of nocturnal drainage flows within a valley in northern California. The results indicate that the degree of interaction of the drainage flows with the larger scale regional flows are strongly dependent on how well the shallow drainage flows are shielded by the surrounding topography from the external environment. For the valley under study, the drainage flows from about mid-slope elevations and below were generally decoupled from the externally generated flows; as evidenced by the similarity of the surface tracer distribution produced during widely varying regional flow conditions. However, tracers released immediately above the drainage flows near the ridge top did reveal considerable mixing between the transition layer flows and the underlying surface drainage flows. Likewise, the transport and dispersion of the tracers at elevated heights within the valley basin were extremely dependent on the influences of the regional scale flows on the valley circulation. The dispersion rates associated with the transition layer flows were dependent on topographic constraints but were appreciably higher than those reported for homogeneous flat terrain situations.

  4. Isotope pattern deconvolution as rising tool for isotope tracer studies in environmental research

    Science.gov (United States)

    Irrgeher, Johanna; Zitek, Andreas; Prohaska, Thomas

    2014-05-01

    During the last decade stable isotope tracers have emerged as versatile tool in ecological research. Besides 'intrinsic' isotope tracers caused by the natural variation of isotopes, the intentional introduction of 'extrinsic' enriched stable isotope tracers into biological systems has gained significant interest. Hereby the induced change in the natural isotopic composition of an element allows amongst others for studying the fate and fluxes of metals, trace elements and species in organisms or provides an intrinsic marker or tag of particular biological samples. Due to the shoreless potential of this methodology, the number of publications dealing with applications of isotope (double) spikes as tracers to address research questions in 'real world systems' is constantly increasing. However, some isotope systems like the natural Sr isotopic system, although potentially very powerful for this type of application, are still rarely used, mainly because their adequate measurement/determination poses major analytical challenges; as e.g. Sr is available in significant amounts in natural samples. In addition, biological systems underlie complex processes such as metabolism, adsorption/desorption or oxidation/reduction. As a consequence, classic evaluation approaches such as the isotope dilution mass spectrometry equation are often not applicable because of the unknown amount of tracer finally present in the sample. Isotope pattern deconvolution (IPD), based on multiple linear regression, serves as simplified alternative data processing strategy to double spike isotope dilution calculations. The outstanding advantage of this mathematical tool lies in the possibility of deconvolving the isotope pattern in a spiked sample without knowing the quantities of enriched isotope tracer being incorporated into the natural sample matrix as well as the degree of impurities and species-interconversion (e.g. from sample preparation). Here, the potential of IPD for environmental tracer

  5. Reliability of assessing dye penetration along root canal fillings using methylene blue

    NARCIS (Netherlands)

    Souza, E.M.; Pappen, F.G.; Shemesh, H.; Bonato-Estrela, C.; Bonetti-Filho, I.

    2009-01-01

    Methylene blue (MB) remains the most frequently used tracer for dye penetration tests of endodontic fillings, despite its chemical reactions with different materials. This study checked whether dye penetration displayed by MB is comparable to Rhodamine B (RB). One hundred and seventy-two root canals

  6. Reliability of assessing dye penetration along root canal fillings using methylene blue

    NARCIS (Netherlands)

    Souza, E.M.; Pappen, F.G.; Shemesh, H.; Bonato-Estrela, C.; Bonetti-Filho, I.

    2009-01-01

    Methylene blue (MB) remains the most frequently used tracer for dye penetration tests of endodontic fillings, despite its chemical reactions with different materials. This study checked whether dye penetration displayed by MB is comparable to Rhodamine B (RB). One hundred and seventy-two root canals

  7. Adsorption of dyes using peat: equilibrium and kinetic studies.

    Science.gov (United States)

    Sepúlveda, L; Fernández, K; Contreras, E; Palma, C

    2004-09-01

    In recent years, adsorption has been accepted as one of the most appropriate processes for decolorization of wastewaters. This paper presents experimental results on application of peat for removal of structurally diverse dyes (azo, oxazine, triphenylmethane, thiazine and others) with emphasis on relevant factors such as the adsorbate-adsorbent chemical properties and chemical interaction as well as adsorption conditions. The equilibrium experimental results were fitted to Langmuir and Freundlich isotherms to obtain the characteristic parameters of each model. According to the evaluation using the Langmuir equation, the maximum sorption capacity of basic dyes at 22 degrees C was 667 (mg g(-1)) for Basic Blue 24, 526 (mg g(-1)) for Basic Green 4 and 714 (mg g(-1)) for Basic Violet 4. On the other hand for Acid Black 1 it was only 25 (mg g(-1)). Batch kinetics studies were undertaken and the data evaluated in compliance with chemical sorption mechanisms. For all of the systems studied the pseudo-second order model provided the best correlation of the kinetic experimental data. A film-pore double resistance diffusion model for mass transfer has also been used in this study to determine the effective diffusivity, Deff, for the adsorption of basic dyes in to peat.

  8. A Study Plan for Determining Recharge Rates at the Hanford Site Using Environmental Tracers

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, E. M.; Szecsody, J. E.; Phillips, S. J.

    1991-02-01

    This report presents a study plan tor estimating recharge at the Hanford Site using environmental tracers. Past operations at the Hanford Site have led to both soil and groundwater contamination, and recharge is one of the primary mechanisms for transporting contaminants through the vadose zone and into the groundwater. The prediction of contaminant movement or transport is one aspect of performance assessment and an important step in the remedial investigation/feasibility study (RI/FS) process. In the past, recharge has been characterized by collecting lysimeter data. Although lysimeters can generate important and reliable data, their limitations include 1) fixed location, 2) fixed sediment contents, 3) edge effects, 4) low rates, and 5) relatively short duration of measurement. These limitations impact the ability to characterize the spatial distribution of recharge at the Hanford Site, and thus the ability to predict contaminant movement in the vadose zone. An alternative to using fixed lysimeters for determining recharge rates in the vadose zone is to use environmental tracers. Tracers that have been used to study water movement in the vadose zone include total chloride, {sup 36}CI, {sup 3}H, and {sup 2}H/{sup 18}O. Atmospheric levels of {sup 36}CI and {sup 3}H increased during nuclear bomb testing in the Pacific, and the resulting "bomb pulse" or peak concentration can be measured in the soil profile. Locally, past operations at the Hanford Site have resu~ed in the atmospheric release of numerous chemical and isotopic tracers, including nitrate, {sup 129}I, and {sup 99}Tc. The radionuclides, in particular, reached a well-defined atmospheric peak in 1945. Atmospheric releases of {sup 129}I and {sup 99}Tc were greatly reduced by mid-1946, but nitrogen oxides continued to be released from the uranium separations facilities. As a result, the nitrate concentrations probably peaked in the mid-1950s, when the greatest number of separations facilities were operating

  9. An assessment of selected properties of the fluorescent tracer, Tinopal CBS-X related to conservative behavior, and suggested improvements

    Science.gov (United States)

    Licha, Tobias; Niedbala, Anne; Bozau, Elke; Geyer, Tobias

    2013-03-01

    SummaryA conservative or well known reactive behavior of water tracers is a prerequisite in the quantitative evaluation of their tracer breakthrough curves. The fluorescent dye, Tinopal CBS-X, is one of the few licensed fluorescent dyes for water tracing with safe use. Its main advantage is its blue fluorescence, which is barely visible to the human eye and thus can be used when coloring water must be avoided. However, scientists have described the recovery of this dye as poor to very poor in field tracer experiments. Hence, this study focuses on examining the interaction of the main water chemistry with Tinopal CBS-X by determining the solubility products of the dye with most common cations. The findings of this investigation reveal that the tracer forms precipitates of very low aqueous solubility with di- and trivalent cations (pKsp 6.4-16.8). As a consequence, Tinopal CBS-X is not a conservative tracer and respective tracer breakthrough curves will exhibit strong tailings at least in part, as result of precipitations formed. The addition of a chemical modifier, EDTA, is suggested to enhance the solubility of Tinopal CBS-X in order to overcome its non-conservative behavior. Equations for estimating the amount of EDTA necessary are provided. In the light of these results, earlier reported tracer breakthrough curves are revisited and re-interpreted.

  10. TRACER STUDY FK UNAND 2008 : PERSEPSI ALUMNI TERHADAP PELAKSANAAN PENDIDIKAN KEDOKTERAN DI FAKULTAS KEDOKTERAN UNIVERSITAS ANDALAS

    Directory of Open Access Journals (Sweden)

    Yulistini Yulistini

    2010-09-01

    Full Text Available AbstrakTracer Study adalah penelitian yang menghimpun informasi tentang sebaran para alumni dan berbagai masukan yang dapat membantu pengembangan kurikulum dan proses pembelajaran di Fakultas Kedokteran Universitas Andalas (FK Unand.Penelitian tracer study di FK Unand 2008 menggunakan pendekatan kuantitatif dengan metode deskriptif analitik. Respondennya adalah alumni FK Unand yang dipilih secara purposive random sampling, yaitu berdasarkan keikutsertaan kegia-tan ilmiah dan kegiatan lainnya di FK Unand tahun 2008.Hasil penelitian menunjukkan persentase responden yang puas dan tidak puas terhadap pelayanan akademik sebanyak 55,5% dan 45,5% dari 124 responden. 61,9% responden merasa puas terhadap pendidikan preklinik dan 50,4% merasa puas terhadap pendidikan klinik. Untuk penilaian kompetensi berdasarkan persepsi responden menunjukkan 66,7% merasa kompeten saat menyelesaikan pendidikan. Uji bivariant menunjukkan hubungan bermakna antara kepuasan terhadap pendidikan preklinik dan klinik, tahun masuk dan jenis kelamin terhadap kompetensi (p<0.05.Kesimpulan adalah sebagian besar responden merasa puas terhadap pelayanan akademik dan pendidikan preklinik. Persentase ketidakpuasan terhadap pen-didikan klinik hanya sedikit lebih tinggi dari pada yang puas. Terdapat hubungan yang bermakna antara kepuasan terhadap pendidikan preklinik, klinik, tahun masuk, dan gender terhadap persepsi responden terhadap kompetensi mereka.Kata kunci :tracer study, alumni, tahun masuk, pre klinik, klinik, kompetensiAbstractTracer Study is a research that gather information about the distribution of the alumni and the various inputs that may help the development of curriculum and learning process in the Faculty of medicine Andalas University (FK Unand Tracer studies FK Unand 2008 using a quantitative approach with a descriptiveARTIKEL PENELITIAN168analytical method. Respondents are FK Unand’s graduates that selected by purposively random sampling, who followed FK Unand

  11. Applied tracers for the observation of subsurface stormflow at the hillslope scale

    OpenAIRE

    J. Wienhöfer; Germer, K.; F. Lindenmaier; Färber, A.; Zehe, E.

    2009-01-01

    Rain fall-runoff response in temperate humid headwater catchments is mainly controlled by hydrolo gical processes at the hillslope scale. Applied tracer experiments with fluore scent dye and salt tracers are well known tools in groundwater studies at the large scale and vadose zone studies at the plot scale, where they provide a means to characterise subsurface flow. We extend this approach to the hillslope scale to investigate saturated and unsaturated flow path s concertedly at a forested h...

  12. Fallout Radionuclides as Tracers in Southern Alps Sediment Studies

    Science.gov (United States)

    Carey, A. E.; Karanovic, Z.; Dibb, J. E.

    2005-12-01

    The primary geologic processes shaping the landscape are physical and chemical weathering and the transport of solids by erosion. As part of our studies on the coupling between physical erosion and chemical weathering, we have determined depositional and erosional processes in New Zealand's tectonically active, rapidly uplifting Southern Alps, specifically focusing on the Hokitika River watershed. The South Island watersheds we are studying are subject to extreme orographic precipitation (as high as 7-12 m annually) and high landslide frequency, but have modest topography due to the rapid erosion. In concert with our studies of chemical weathering and physical erosion, we have used the atmospherically-delivered radionuclides of 7Be, 137Cs and 210Pbexcess to determine the relative magnitude of particle residence time in the high elevation Cropp and Whitcombe subwatersheds and the rates of sedimentation. One- and two-box modeling with 7Be and 210Pbexcess was used to determine soil and sediment residence times. Residence time of fine suspended particles is short and particles can travel the length of the river during a single storm, probably due to the short duration, high-intensity rainfalls which produce rapidly moving, steep flood waves. The readily detected peak of 137Cs activity in Cropp terrace and Hokitika gorge soils yielded sedimentation rates of 0.06-0.12 cm yr-1. At the Cropp terrace, inventory models of 210Pbexcess yield soil accumulation rates significantly less than those determined using the 137Cs activity peak. We attribute the differences to overestimation of 210Pbexcess in surface soils and to contrasting fallout fluxes, geochemical behavior and radionuclide contents of sedimenting materials. Total inventories of 210Pbexcess in soils greatly exceed the expected direct atmospheric deposition, suggesting that lateral transport of this nuclide occurs within the watershed. At the Hokitika gorge, all nuclides studied yielded similar sedimentation rates

  13. A tracer study in an Alaskan gravel beach and its implications on the persistence of the Exxon Valdez oil.

    Science.gov (United States)

    Li, Hailong; Boufadel, Michel C

    2011-06-01

    Despite great efforts including bioremediation, the 1989 Exxon Valdez oil spills persist in many gravel beaches in Prince William Sound, Alaska, USA. To explore this mystery, a lithium tracer study was conducted along two transects on one of these beaches. The tracer injections and transports were successfully simulated using the 2-dimensional numerical model MARUN. The tracer stayed much longer in the oil-persisting, right transect (facing landwand) than in the clean, left transect. If the tracer is approximately regarded as oils, oils in the upper layer would have more opportunities to enter the lower layer in the right transect than in the left one. This may qualitatively explain the oil persistence within the right transect. When the tracer is regarded as nutrients, the long stay of nutrients within the right transect implies that the oil persistence along the right transect was not due to the lack of nutrients during the bioremediation.

  14. A Mathematical Modeling Study of Tracer Mixing in a Continuous Casting Tundish

    Science.gov (United States)

    Chen, Chao; Jonsson, Lage Tord Ingemar; Tilliander, Anders; Cheng, Guoguang; Jönsson, Pär Göran

    2015-02-01

    A mathematical model based on a water model was developed to study the tracer mixing in a single strand tundish. The mixing behavior of black ink and KCl solution was simulated by a mixed composition fluid model, and the data were validated by water modeling results. In addition, a model that solves the scalar transport equation (STE) without any physical properties of the tracer was studied and the results were compared to predictions using the density-coupled model. Furthermore, the mixing behaviors of different amounts of KCl tracers were investigated. Before the model was established, KCl tracer properties such as the KCl molecule diffusion (KMD), the water molecule self-diffusion (WSD) in KCl solution, and the KCl solution viscosity (KV) were evaluated. The RTD curve of 250 mL KCl for the KMD case was closer to the water modeling results than that of the case implemented with only density. Moreover, the ensemble average deviation of the RTD curves of the cases implemented with KMD + WSD, KMD + KV, and KMD + WSD + KV to the KMD case is less than 0.7 pct. Thus, the water self-diffusion and KV were neglected, while the KCl density and KMD were implemented in the current study. The flow pattern of black ink was similar to the STE result i.e., the fluid flowed upwards toward the top surface and formed a large circulating flow at the outlet nozzle. The flow behavior of the 100, 150, and 250 mL KCl cases exhibited a strong tendency to sink to the tundish bottom, and subsequently flow through the holes in the dam. Thereafter, it propagated toward the outlet nozzle. Regarding the KCl tracer amount, the tracer concentration propagated to the outlet nozzle much faster for the larger amount case than for the smaller amount cases. However, the flow pattern for the 50 mL KCl case was somewhat different. The fluid propagated to the top surface which acted like black ink during the initial injection, and subsequently the fluid flowed throughout the holes at a much slower pace

  15. National Biomedical Tracer Facility (NBTF). Project definition study: Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Lagunas-Solar, M.C.

    1995-02-15

    This report describes a five-year plan for the construction and commissioning of a reliable and versatile NBTF facility for the production of high-quality, high-yield radioisotopes for research, biomedical, and industrial applications. The report is organized in nine sections providing, in consecutive order, responses to the nine questions posed by the U.S. Department of Energy in its solicitation for the NBTF Project Definition Study. In order to preserve direct correspondence (e.g., Sec. 3 = 3rd item), this Introduction is numbered {open_quotes}0.{close_quotes} Accelerator and facility designs are covered in Section 1 (Accelerator Design) and Section 2 (Facility Design). Preliminary estimates of capital costs are detailed in Section 3 (Design and Construction Costs). Full licensing requirements, including federal, state, and local ordinances, are discussed in Section 4 (Permits). A plan for the management of hazardous materials to be generated by NBTF is presented in Section 5 (Waste Management). An evaluation of NBTF`s economic viability and its potential market impact is detailed in Section 6(Business Plan), and is complemented by the plans in Section 7 (Operating Plan) and Section 8 (Radioisotope Plan). Finally, a plan for NBTF`s research, education, and outreach programs is presented in Section 9 (Research and Education Programs).

  16. Textile dye degradation by bacterial consortium and subsequent toxicological analysis of dye and dye metabolites using cytotoxicity, genotoxicity and oxidative stress studies.

    Science.gov (United States)

    Phugare, Swapnil S; Kalyani, Dayanand C; Patil, Asmita V; Jadhav, Jyoti P

    2011-02-15

    The present study aims to evaluate Red HE3B degrading potential of developed microbial consortium SDS using two bacterial cultures viz. Providencia sp. SDS (PS) and Pseudomonas aeuroginosa strain BCH (PA) originally isolated from dye contaminated soil. Consortium was found to be much faster for decolorization and degradation of Red HE3B compared to the individual bacterial strain. The intensive metabolic activity of these strains led to 100% decolorization of Red HE3B (50 mg l(-1)) with in 1h. Significant induction of various dye decolorizing enzymes viz. veratryl alcohol oxidase, laccase, azoreductase and DCIP reductase compared to control, point out towards their involvement in overall decolorization and degradation process. Analytical studies like HPLC, FTIR and GC-MS were used to scrutinize the biodegradation process. Toxicological studies before and after microbial treatment was studied with respect to cytotoxicity, genotoxicity, oxidative stress, antioxidant enzyme status, protein oxidation and lipid peroxidation analysis using root cells of Allium cepa. Toxicity analysis with A. cepa signifies that dye Red HE3B exerts oxidative stress and subsequently toxic effect on the root cells where as biodegradation metabolites of the dye are relatively less toxic in nature. Phytotoxicity studies also indicated that microbial treatment favors detoxification of Red HE3B.

  17. A comparative study on biosorption characteristics of certain fungi for bromophenol blue dye.

    Science.gov (United States)

    Zeroual, Youssef; Kim, Beom Su; Kim, Choel Sang; Blaghen, Mohamed; Lee, Kang Min

    2006-07-01

    Laboratory investigations of the potential use of dried biomasses of Rhizopus stolonifer, Fusarium sp., Geotrichum sp., and Aspergillus fumigatus as biosorbents for the removal of bromophenol blue (BPB) dye from aqueous solutions were conducted. Kinetics studies indicated that the BPB dye uptake processes can be well described by the pseudo-second-order model. The fungal biomasses exhibited the highest dye biosorption at pH 2.0. The Langmuir adsorption model appears to fit the dye biosorption better than the Freundlich model, with maximum dye uptake capacities ranging from 526 to 1,111 mg/g, depending on the biomass used.

  18. Solute movement in drained fen peat: a field tracer study in a Somerset (UK) wetland

    Science.gov (United States)

    Baird, Andrew J.; Gaffney, Simon W.

    2000-10-01

    Little is known about solute transport in peats, despite the obvious importance of solute transport on eco-hydrological processes in both managed and natural peatlands. To address this lack of knowledge, we investigated solute transport processes in an agricultural fen peat using a conservative KBr tracer. The main aim of the study was to elucidate solute transport behaviour in general in this peat, with a more specific aim of investigating whether preferential or bypassing flow occurred. The tracer moved through the peat more rapidly than expected, and the pattern of movement showed clear evidence of plot-scale bypassing flow. The data also provide evidence that bypassing flow occurs in pores at smaller scales. The implications of this study for management of wetland pastures in the Somerset Moors in south-west England are discussed.

  19. Joint DOE/NRC field study of tracer migration in the unsaturated zone

    Energy Technology Data Exchange (ETDEWEB)

    Nyhan, J.; Polzer, W.; Essington, E.; Cokal, E.; Lane, L.; Lopez, E.; Stallings, E.; Walker, R.

    1986-03-01

    The results of a joint DOE/NRC field experiment to evaluate leaching and transport of solutes in a sandy silt backfill used for shallow land burial operations at Los Alamos are presented for steady-state and unsteady-state flow conditions. The migration of iodide, bromide, and lithium through the backfill material is studied as functions of depth and time and they are compared with one another. The bromide and iodide tracer data are used to estimate the diffusion coefficient, the tortuosity factor, and dispersivity. These values are used to calculate effective dispersion coefficients for subsequent analyses of the retardation factor and the distribution coefficient for lithium using least squares procedures. The results of the tracer migration study are discussed relative to challenges facing the waste management community, and chemical transport modeling opportunities are presented for a modeling workshop to be held in FY86.

  20. Preliminary study on the dye removal efficacy of immobilized marine ...

    African Journals Online (AJOL)

    SAM

    2014-05-28

    May 28, 2014 ... immobilized marine and freshwater microalgal beads ... Discharge of textile wastewater containing toxic dyes can adversely affect aquatic organisms and human health. .... the bioavailability of pollutants like metals, dye.

  1. Organics Verification Study for Sinclair and Dyes Inlets, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Kohn, Nancy P.; Brandenberger, Jill M.; Niewolny, Laurie A.; Johnston, Robert K.

    2006-09-28

    Sinclair and Dyes Inlets near Bremerton, Washington, are on the State of Washington 1998 303(d) list of impaired waters because of fecal coliform contamination in marine water, metals in sediment and fish tissue, and organics in sediment and fish tissue. Because significant cleanup and source control activities have been conducted in the inlets since the data supporting the 1998 303(d) listings were collected, two verification studies were performed to address the 303(d) segments that were listed for metal and organic contaminants in marine sediment. The Metals Verification Study (MVS) was conducted in 2003; the final report, Metals Verification Study for Sinclair and Dyes Inlets, Washington, was published in March 2004 (Kohn et al. 2004). This report describes the Organics Verification Study that was conducted in 2005. The study approach was similar to the MVS in that many surface sediment samples were screened for the major classes of organic contaminants, and then the screening results and other available data were used to select a subset of samples for quantitative chemical analysis. Because the MVS was designed to obtain representative data on concentrations of contaminants in surface sediment throughout Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage, aliquots of the 160 MVS sediment samples were used in the analysis for the Organics Verification Study. However, unlike metals screening methods, organics screening methods are not specific to individual organic compounds, and are not available for some target organics. Therefore, only the quantitative analytical results were used in the organics verification evaluation. The results of the Organics Verification Study showed that sediment quality outside of Sinclair Inlet is unlikely to be impaired because of organic contaminants. Similar to the results for metals, in Sinclair Inlet, the distribution of residual organic contaminants is generally limited to nearshore areas already within the

  2. Field studies of streamflow generation using natural and injected tracers on Bickford and Walker Branch Watersheds

    Energy Technology Data Exchange (ETDEWEB)

    Genereux, D.; Hemond, H. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Civil Engineering; Mulholland, P. [Oak Ridge National Lab., TN (United States)

    1992-05-01

    Field studies of streamflow generation were undertaken on two forested watersheds, the West Road subcatchment of Bickford Watershed in central Massachusetts and the West Fork of Walker Branch Watershed in eastern Tennessee. A major component of the research was development of a two-stage methodology for the use of naturally-occurring {sup 222}Rn as a tracer. The first of the two stages was solving a mass-balance equation for {sup 222}Rn around a stream reach of interest in order to calculate Rn{sub q}, the {sup 222}Rn content of the lateral inflow to the reach; a conservative tracer (chloride) and a volatile tracer (propane) were injected into the study stream to account for lateral inflow to, and volatilization from, the study reach. The second stage involved quantitative comparison of Rn{sub q} to the measured {sup 222}Rn concentrations of different subsurface waters in order to assess how important these waters were in contributing lateral inflow to the stream reach.

  3. Application of tracer packet technique for multielemental uptake studies on the inorganic ion exchanger zirconium vanadate

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Kamalika; Basu, S.; Ramaswami, A.; Lahiri, Susanta E-mail: slahiri@hp1.saha.ernet.in

    2003-09-01

    The conception of tracer packet was first started with the irradiation of a thick cobalt target with {sup 16}O, {sup 7}Li and {sup 12}C beams, consecutively. This produced carrier-free radiotracers of Mn, Cu, Zn, Ga, Ge, As and Se. These elements are adjacent members in the periodic table and are of nutritional importance. Another 'tracer packet', which was subsequently designed, was of heavy and toxic metals. A gold target irradiated with medium energy {sup 7}Li and {sup 12}C produced {sup 197}Hg, {sup 200}Tl, {sup 200}Pb, {sup 204}Bi, {sup 204}Po. The uptake of these elements has been studied using two different ion exchangers, one of inorganic origin and the other of chelating type.

  4. STRATEGIES FOR QUANTIFYING PET IMAGING DATA FROM TRACER STUDIES OF BRAIN RECEPTORS AND ENZYMES.

    Energy Technology Data Exchange (ETDEWEB)

    Logan, J.

    2001-04-02

    A description of some of the methods used in neuroreceptor imaging to distinguish changes in receptor availability has been presented in this chapter. It is necessary to look beyond regional uptake of the tracer since uptake generally is affected by factors other than the number of receptors for which the tracer has affinity. An exception is the infusion method producing an equilibrium state. The techniques vary in complexity some requiring arterial blood measurements of unmetabolized tracer and multiple time uptake data. Others require only a few plasma and uptake measurements and those based on a reference region require no plasma measurements. We have outlined some of the limitations of the different methods. Laruelle (1999) has pointed out that test/retest studies to which various methods can be applied are crucial in determining the optimal method for a particular study. The choice of method will also depend upon the application. In a clinical setting, methods not involving arterial blood sampling are generally preferred. In the future techniques for externally measuring arterial plasma radioactivity with only a few blood samples for metabolite correction will extend the modeling options of clinical PET. Also since parametric images can provide information beyond that of ROI analysis, improved techniques for generating such images will be important, particularly for ligands requiring more than a one-compartment model. Techniques such as the wavelet transform proposed by Turkheimer et al. (2000) may prove to be important in reducing noise and improving quantitation.

  5. NON-LCL AND TRACER TEST FOR GROUNDWATER FLOW IN A SINGLE FRACTURE

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The validity of Local Cubic Law (LCL) is an important issue to study groundwater flow and transport in fractured media. According to laboratory simulaion tests, the average velocity with a lower gradient in a single fracture is calculated by the LCL, which is compared with the measured average velocity. Then dye tracer test is designed and completed. The evidence for non-LCL is drawn from the results of the simulation tests and the dye tracer tests. Then the Reynolds number of groundwater is calculated, the critical value of Re for laminar flow is discussed in a single fracture under different conditions. The motion types for groundwater flow have been discussed.

  6. [Experimental study of immune reactivity in Swiss mice due to topical administration of three textile dyes].

    Science.gov (United States)

    Gavăt, C C; Lupuşoru, R V; Ghiciuc, Cristina Mihaela; Lupuşoru, Cătălina Elena

    2010-01-01

    Reactive Red 183, Reactive Red 2 and Reactive Blue 204 (red dye, green dye and blue dye) are three reactive dyes frequently used in textile industry. In some atmospheric conditions ( high temperature, perspiration, pH values, UV/IR radiations), some quantities of these hydrolyzed dyes, could pass from textile clothes directly into the human skin. There were used 4 groups of white Swiss mice (with similar weight and number of both sexes), control group and 3 groups, treated once daily with a retro-auricular application of different reactive dyes. After 14 days of treatment, blood samples were taken from retro-orbitary plexus to assess leukocyte count, phagocytic capacity of peripheral neutrophils, serum opsonic capacity, phagocyte capacity and bactericidal capacity of peritoneal macrophages, splenic T lymphocytes with rossetting capacity and spleen cells forming Jerne plaques. The retro-acuricular and latero-cervical nodes were weighted. Red dye did not influence the weight of the studied nodes, but determined statistically significant modifications on non-specific immune system parameters. Blue and grena dyes determined modifications of weight especially of retroauricular nodes. Grena dye determined important effects of non-specific immune system parameters (serum opsonic capacity, phagocyte capacity and bactericidal capacity of peritoneal macrophages). The blue dye did not determine a biological response. Red and green dye determined important effects on non-specific immune system parameters.

  7. Dye adsorption of cotton fabric grafted with PPI dendrimers: Isotherm and kinetic studies.

    Science.gov (United States)

    Salimpour Abkenar, Samera; Malek, Reza Mohammad Ali; Mazaheri, Firouzmehr

    2015-11-01

    In this research, the cotton fabrics grafted with two generations of the poly(propylene imine) dendrimers were applied to adsorb textile dyes from aqueous solutions. Direct Red 80 (anionic dye), Disperse Yellow 42 (nonionic dye) and Basic Blue 9 (cationic dye) were selected as model dyes. The effect of various experimental parameters such as initial concentration of dyes, charge of dyes molecule, salt and pH was investigated on the adsorption process. Furthermore, kinetics and equilibrium of the adsorption process on the grafted samples were studied. It was found that maximum adsorption of anionic and disperse dyes took place at around pH 3, while cationic dye could be adsorbed at around pH 11. The Langmuir equation was able to describe the mechanism of dyes adsorption. In addition, the second-order equation was found to be fit with the kinetics data. Interestingly, it seems that the dye adsorption of the grafted fabrics is strongly pH dependent.

  8. Compound study on low salt dyeing dark trichromatic reactive dyes%低盐活性染料深三原色的复配研究

    Institute of Scientific and Technical Information of China (English)

    赵雪; 陈美芬; 简卫; 赵德峰

    2012-01-01

    Novel low salt dyeing dark trichromatic reactive dyes were compounded, optimal ratio was obtained by studying the effect of different monomer compound ratios on dyeing performance. Dyeing build up and dyeing fastness were compared between self-made low salt dyeing dark trichromatic reactive dyes and monomers.%复配了新型低盐活性染料深三原色,研究了不同单体之间的复配比例对染料染色性能的影响,得到了最佳复配比例。对低盐活性染料深三原色与复配的染料单体在染色提升力和染色牢度等方面进行了对比研究。

  9. Density Functional Theory (DFT Study of Coumarin-based Dyes Adsorbed on TiO2 Nanoclusters—Applications to Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Mihai A. Gîrţu

    2013-06-01

    Full Text Available Coumarin-based dyes have been successfully used in dye-sensitized solar cells, leading to photovoltaic conversion efficiencies of up to about 8%. Given the need to better understand the behavior of the dye adsorbed on the TiO2 nanoparticle, we report results of density functional theory (DFT and time-dependent DFT (TD-DFT studies of several coumarin-based dyes, as well as complex systems consisting of the dye bound to a TiO2 cluster. We provide the electronic structure and simulated UV-Vis spectra of the dyes alone and adsorbed to the cluster and discuss the matching with the solar spectrum. We display the energy level diagrams and the electron density of the key molecular orbitals and analyze the electron transfer from the dye to the oxide. Finally, we compare our theoretical results with the experimental data available and discuss the key issues that influence the device performance.

  10. Colorimetric studies of some newly synthesized bisazo reactive dyes

    OpenAIRE

    2016-01-01

    A series of cold brand bisazo reactive dyes (4a–h) were obtained by the coupling of tetrazotised 4,4′-methylene-bis(2-methyl-5-nitro aniline) (2) with various cyanurated coupling components (3a–h) in good yield. Their dyeing performances as reactive dyes have been assessed on silk, wool and cotton fabrics. These dyes were characterized by UV–Vis, FTIR, 1H NMR spectroscopic techniques elemental analysis. The percentage dye bath exhaustion and fixation on different fibers were found to be very ...

  11. Study of TiO2 particles size, dyes, and catalyst to improve the performance of DSSC

    Science.gov (United States)

    Saehana, Sahrul; Darsikin, Muslimin

    2016-02-01

    This study reports effort to improve performance of solar cells by using various natural dyes in dye-sensitized solar cell (DSSC). We applied three kind of natural dye, i.e, black rice dye, cactus dye and dragon fruit dye. We found that performance of DSSC which employ black rice dye was higher than other natural dyes. It is because the wider spectrum wavelength of black rice dyes. Its performance also compared with rhutenium dye (N719). Effect of TiO2 particle to DSSC performance was also investigated. It was concluded that smaller TiO2 particle size will increase the performance of DSSC solar cells. It was because the smaller particle size (high surface area) will load more dye. In addition, we also demonstrated the use of graphite from lead pencil as counter electrode.

  12. Sentinel lymph node biopsy in breast cancer--experience with the combined use of dye and radioactive tracer at Aarhus University Hospital

    DEFF Research Database (Denmark)

    Lauridsen, Mette Cathrine; Garne, Jens Peter; Sørensen, Flemming Brandt

    2004-01-01

    -needle aspiration biopsy (FNAB) were not included. For identifying the SLNs, a combination of Tc-99m-labelled human albumin (Solco-ALBU-RES) and blue dye (Patent Blue V) was used. No lymphoscintigraphy was performed. The SLN was successfully identified in 122 out of 124 (98%) patients and 66 (54%) patients were...

  13. In Vitro Polarized Resonance Raman Study of N719 and N719-TBP in Dye Sensitized Solar Cells

    DEFF Research Database (Denmark)

    Hassing, Søren; Jernshøj, Kit Drescher; Lund, Torben;

    2016-01-01

    Abstract: The working efficiency of dye-sensitized solar cells (DSCs) depends on the long-term stability of the dye itself and on the microscopic structure of the dye-semiconductor interface. Previous experimental studies of DSCs based on ruthenium dye with bipyridine ligands (N719) adsorbed...

  14. Experimental study of dye removal from industrial wastewater by membrane technologies of reverse osmosis and nanofiltration

    Directory of Open Access Journals (Sweden)

    Abid Mohammad Fadhil

    2012-12-01

    Full Text Available Abstract Currently, biological method has been utilized in the treatment of wastewater -containing synthetic dyes used by textile industries in Iraq. The present work was devoted to study the operating feasibility using reverse osmosis (RO and nanofiltration (NF membrane systems as an alternative treatment method of wastewater discharged from Iraqi textile mills. Acid red, reactive black and reactive blue dyes were selected, based on the usage rate in Iraq. Effects of dye concentration, pH of solution, feed temperature, dissolved salts and operating pressure on permeate flux and dye rejection were studied. Results at operating conditions of dye concentration = 65 mg/L, feed temperature = 39°C and pressure = 8 bar showed the final dye removal with RO membrane as 97.2%, 99.58% and 99.9% for acid red, reactive black and reactive blue dyes, respectively. With NF membrane, the final dye removal were as 93.77%, 95.67%, and 97% for red, black and blue dyes, respectively. The presence of salt (particularly NaCl in the dye solution resulted in a higher color removal with a permeate flux decline. It was confirmed that pH of solution had a positive impact on dye removal while feed temperature showed a different image. A comparison was made between the results of dye removal in biological and membrane methods. The results showed that membrane method had higher removal potential with lower effective cost. The present study indicates that the use of NF membrane in dye removal from the effluent of Iraqi textile mills is promising.

  15. Experimental Study of Dye Removal from Industrial Wastewater by Membrane Technologies of Reverse Osmosis and Nanofiltration

    Directory of Open Access Journals (Sweden)

    Mohammad Fadhil Abid

    2012-12-01

    Full Text Available Currently, biological method has been utilized in the treatment of wastewater -containing synthetic dyes used by textile industries in Iraq. The present work was devoted to study the operating feasibility using reverse osmosis (RO and nanofiltration (NF membrane systems as an alternative treatment method of wastewater discharged from Iraqi textile mills. Acid red, reactive black and reactive blue dyes were selected, based on the usage rate in Iraq. Effects of dye concentration, pH of solution, feed temperature, dissolved salts and operating pressure on permeate flux and dye rejection were studied. Results at operating conditions of dye concentration?=?65 mg/L, feed temperature?=?39?C and pressure?=?8 bar showed the final dye removal with RO membrane as 97.2%, 99.58% and 99.9% for acid red, reactive black and reactive blue dyes, respectively. With NF membrane, the final dye removal were as 93.77%, 95.67%, and 97% for red, black and blue dyes, respectively. The presence of salt (particularly NaCl in the dye solution resulted in a higher color removal with a permeate flux decline. It was confirmed that pH of solution had a positive impact on dye removal while feed temperature showed a different image. A comparison was made between the results of dye removal in biological and membrane methods. The results showed that membrane method had higher removal potential with lower effective cost. The present study indicates that the use of NF membrane in dye removal from the effluent of Iraqi textile mills is promising.

  16. Study on the removal of acid dyes using chitosan as a natural coagulant/coagulant aid.

    Science.gov (United States)

    Zonoozi, M H; Alavi Moghaddam, M R; Arami, M

    2011-01-01

    Chitosan was selected as a natural coagulating agent for the removal of acid dyes (Acid Blue 292; AB292, and Acid Red 398; AR398) from dye-containing solutions. The study was organised in two phases. In phase 1, chitosan was used alone as a natural coagulant for the removal of the dyes. For this purpose, the effect of different parameters including pH, chitosan dosage and initial dye concentration on the dye removal efficiency was examined. In phase 2 of the study, the application of chitosan as a natural coagulant aid in conjunction with polyaluminium chloride (PAC) was assessed. According to the results of phase 1, the best removal efficiencies occurred in an acidic pH range (less than 6) for both of the dyes. Also, excellent dye removal results (about 90%) were achieved with relatively low dosages of chitosan (30-35 mg L(-1) for AB292 and 50-60 mg L(-1) for AR398). However, the initial concentration of the dyes severely influenced the coagulation performance of chitosan, which can constrain the performance of chitosan as a natural coagulant. On the basis of the results of phase 2, chitosan, as a natural coagulant aid, noticeably enhanced the dye removal efficiency of PAC, especially in the case of AB292. Small amounts of chitosan (3 or 5 mg L(-1)) enhanced the dye removal efficiency of PAC up to 2.5 times for AB292.

  17. Neonatal Respiratory Diseases in the Newborn Infant: Novel Insights from Stable Isotope Tracer Studies.

    Science.gov (United States)

    Carnielli, Virgilio P; Giorgetti, Chiara; Simonato, Manuela; Vedovelli, Luca; Cogo, Paola

    2016-01-01

    Respiratory distress syndrome is a common problem in preterm infants and the etiology is multifactorial. Lung underdevelopment, lung hypoplasia, abnormal lung water metabolism, inflammation, and pulmonary surfactant deficiency or disfunction play a variable role in the pathogenesis of respiratory distress syndrome. High-quality exogenous surfactant replacement studies and studies on surfactant metabolism are available; however, the contribution of surfactant deficiency, alteration or dysfunction in selected neonatal lung conditions is not fully understood. In this article, we describe a series of studies made by applying stable isotope tracers to the study of surfactant metabolism and lung water. In a first set of studies, which we call 'endogenous studies', using stable isotope-labelled intravenous surfactant precursors, we showed the feasibility of measuring surfactant synthesis and kinetics in infants using several metabolic precursors including plasma glucose, plasma fatty acids and body water. In a second set of studies, named 'exogenous studies', using stable isotope-labelled phosphatidylcholine tracer given endotracheally, we could estimate surfactant disaturated phosphatidylcholine pool size and half-life. Very recent studies are focusing on lung water and on the endogenous biosynthesis of the surfactant-specific proteins. Information obtained from these studies in infants will help to better tailor exogenous surfactant treatment in neonatal lung diseases.

  18. Theoretical study of nonlinear optical properties of some azoic dyes

    Directory of Open Access Journals (Sweden)

    Hadji Djebar

    2015-07-01

    Full Text Available In this paper we presented semi-empirical PM3, ab-initio (HF, MP2 and DFT (B3LYP, B3PW91 calculation of the dipole moment, polarizability, and first hyperpolarizability of some azoics dyes derivatives which have electron donor and electron acceptor groups on either sides. The first hyperpolarizability of these molecules was calculated with PM3 method, HF/6-31G**, HF/6-31+G**, HF/6-31++G**, DFT with B3LYP and B3PW91 functional, and MP2/6-31++G** based on finite field approach using GAUSSIAN03 program. The effects of the intramolecular charge transfer (ICT from the donor to the acceptor groups on the molecular geometry and atomic charge distribution of these NLO chromophores are derived from its HF, MP2 and DFT calculations. The variation of this property has also been correlated to E (HOMO-LUMO gap and to the nature of the highest occupied molecular orbital HOMO and the lowest unoccupied molecular orbital HOMO. The study reveals that the azoics dyes derivatives have large hyperpolarizability values; hence they may be used in the development of nonlinear optical materials.

  19. Study of natural organic dyes as active material for fabrication of organic light emitting diodes

    Science.gov (United States)

    Sánchez Juárez, A.; Castillo, D.; Guaman, A.; Espinosa, S.; Obregón, D.

    2016-09-01

    The scientific community and some sectors of industry have been working with organic dyes for successful applications in OLED's, OSC's, however, most of the used dyes and pigments are synthetic. In this work is investigated the use of natural dyes for its application in organic light emitting diodes, some of the studied species are chili, blackberry, guayacan flower, cochinilla, tree tomato, capuli, etc. In this study the dyes are deposited by direct deposition and SOL-GEL process doped with the natural organic dye, both methods show good performance and lower fabrication costs for dye extraction, this represents a new alternative for the fabrication of OLED devices with low requirements in technology. Most representative results are presented for Dactylopius Coccus Costa (cochinilla) and raphanus sativus' skin.

  20. Dyeing Studies with Eucalyptus, Quercetin, Rutin, and Tannin: A Research on Effect of Ferrous Sulfate Mordant

    Directory of Open Access Journals (Sweden)

    Rattanaphol Mongkholrattanasit

    2013-01-01

    Full Text Available Natural dyes from Eucalyptus leaf extract, quercetin, rutin, and tannin were applied to silk fabric by pad-batch and pad-dry techniques under different conditions. Ferrous sulfate was used as a mordant. The dyeing properties were evaluated by measuring K/S and CIELAB values. In addition, the different fastness properties were evaluated. The effect of dyes at different concentration levels with respect to their colour strength was also studied.

  1. Hetarylazopyrazolone Dyes Based on Benzothiazole and Benzimidazole Ring Systems: Synthesis, Spectroscopic Investigation, and Computational Study

    Directory of Open Access Journals (Sweden)

    Ebru Aktan

    2017-01-01

    Full Text Available In this study, the synthesized coupling component 1-(2-benzothiazolyl-3-methylpyrazol-5-one reacted with diazotised heterocyclic amines to afford six novel hetarylazopyrazolone dyes. These azo dyes based on benzothiazole and benzimidazole ring systems were characterized by spectral methods and elemental analyses. The solvatochromic behaviors of these dyes in various solvents were evaluated. The ground state geometries of the dyes were optimized using density functional theory (DFT. Solvent, acid-base, and substituent influences on the wavelength of the maximum absorption were examined in detail. Time-dependent density functional theory (TD-DFT calculations were performed to obtain the absorption spectra of the dyes in various solvents and the results compared with experimental values. Besides, frontier molecular orbitals (FMO analysis for the dyes is also described from the computational process.

  2. Study on Transfer of Ni in Soil—Plant System Using 63Ni Tracer Method

    Institute of Scientific and Technical Information of China (English)

    TUCONG

    1996-01-01

    A study was carried out on the transfer of native and added Ni towards plant both in different soils and at different time by using 63 Ni tracer technique.The transfer of added Ni in soil was greater than native Ni and declined as time increased.The mobility was greater for soluble plus exchangeable fraction of soil Ni but very smaller for residual and Fe/Mn oxide bound fractions.These indicated that Ni was more mobile and more harmful in soils with a low pH and /or low content of Fe/Mn oxides.

  3. Coumarin Dyes for Dye-Sensitized Solar Cells - A Long-Range-Corrected Density Functional Study

    CERN Document Server

    Wong, Bryan M; 10.1063/1.3025924

    2010-01-01

    The excited-state properties in a series of coumarin solar cell dyes are investigated with a long-range-corrected (LC) functional which asymptotically incorporates Hartree-Fock exchange. Using time-dependent density functional theory (TDDFT), we calculate excitation energies, oscillator strengths, and excited-state dipole moments in each of the dyes as a function of the range-separation paramenter, mu. To investigate the acceptable range of mu and assess the quality of the LC-TDDFT formalism, an extensive comparison is made between LC-BLYP excitation energies and approximate coupled cluster singles and doubles (CC2) calculations. When using a properly-optimized value of mu, we find that the LC technique provides a consistent picture of charge-transfer excitations as a function of molecular size. In contrast, we find that the widely-used B3LYP hybrid functional severely overestimates excited-state dipole moments and underestimates vertical excitations energies, especially for larger dye molecules. The results ...

  4. A study of dyes sorption on biobased cryogels

    Energy Technology Data Exchange (ETDEWEB)

    Dobritoiu, Rodica; Patachia, Silvia, E-mail: st.patachia@unitbv.ro

    2013-11-15

    Three types of biopolymers based materials were synthesized and tested as adsorbents for the dyes from aqueous solutions. Blends based on poly (vinyl alcohol) [PVA] and scleroglucan [Scl], cellulose micro-fibres [cel] and zein, respectively, have been prepared by repeated freezing–thawing cycles. Methylene blue [MB] was selected as a model dye in order to evaluate the capacity of the prepared materials to remove the dyes from aqueous solutions. The effects of the initial dye concentration, contact time and the composition of materials on the kinetic and thermodynamic parameters of sorption were discussed. The pseudo-second-order kinetics was found to better fit the experimental data thus being able to consistently predict the amount of dye adsorbed over the entire sorption period. The sorption equilibrium data obey Freundlich isotherm. Sorption capacity was evaluated both by dye solution and cryogel analysis by using VIS spectrometry and image analysis with CIELAB system. The sorption of monomer or aggregated dye molecules was identified and correlated with the type and morphology of the gel. The highest efficiency in MB removal was obtained for Scl/PVA cryogels in 1:9 weight ratio (9.5279 mg/g MB for an initial concentration by 8 × 10{sup −5} mol/L in MB). These materials are suitable as sorbents for the advanced removal of dyes from waste water.

  5. Sentinel lymph node biopsy in breast cancer--experience with the combined use of dye and radioactive tracer at Aarhus University Hospital

    DEFF Research Database (Denmark)

    Lauridsen, Mette Cathrine; Garne, Jens Peter; Sørensen, Flemming Brandt;

    2004-01-01

    -needle aspiration biopsy (FNAB) were not included. For identifying the SLNs, a combination of Tc-99m-labelled human albumin (Solco-ALBU-RES) and blue dye (Patent Blue V) was used. No lymphoscintigraphy was performed. The SLN was successfully identified in 122 out of 124 (98%) patients and 66 (54%) patients were...... found to have metastatic involvement of the axillary lymph nodes. In 52 (79%) of these patients, the SLNs were the only nodes involved, 28 (54%) had micrometastasis only. The false-negative rate was 1.5%. This method has proven valid in the staging of the axilla in patients with breast cancer...

  6. [Study of achieving white organic LED by fluorescence dye].

    Science.gov (United States)

    Wang, Jin; Wang, Jing; Zheng, Rong-er; Meng, Ji-wu

    2005-08-01

    Some hybrid organic LEDs are made by using fluorescence dye and InGaN blue-light chip and the possibility of achieving white organic LED is investigated according to light conversion theory. Firstly, the LEDs made by normal method and double-dotting glue method are studied. It is found that the double-dotting glue method is too complex and the LEDs made by this way is low-luminance, so it isn't fit to make LED. Secondly the different weight ratio of 1/1/100, 1/1/200, 2/1.5/100 ax-17/zq-13/AB LEDs are manufactured. The 2/1.5/100 LED's color coordinate is (0.32, 0.30), approaching to white point and the correlative color temperature is 6290K which is close to sunlight. So it is a relatively ideal white lamp-house.

  7. Recent progress of {sup 10}Be tracer studies in Chinese loess

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Weijian, E-mail: weijian@loess.llqg.ac.cn [State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061 (China); Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry and Application, Xi’an AMS Center, Xi' an 710061 (China); Joint Center for Global Change Studies, Beijing 100875 (China); Xie, Xingjun [State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061 (China); Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry and Application, Xi’an AMS Center, Xi' an 710061 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Beck, Warren [NSF-Arizona AMS Facility, University of Arizona, Tucson, AZ 85721 (United States); Kong, Xianghui; Xian, Feng; Du, Yajuan; Wu, Zhenkun [State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061 (China); Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry and Application, Xi’an AMS Center, Xi' an 710061 (China)

    2015-10-15

    Studies of cosmogenic {sup 10}Be in Chinese loess began about twenty-five years ago and since then a number of research groups worldwide have contributed to a firm understanding of the production, transport, deposition and storage of {sup 10}Be in loess. The essential characteristics that make {sup 10}Be a useful isotopic tracer in loess, include: (1) dominant atmospheric production directly linked to the intensity of the Earth’s magnetic field; (2) climate-dependent deposition; and (3) subsequent immobility, so that as {sup 10}Be accumulates in a loess profile its stratigraphic integrity is preserved. This fact, combined with very high deposition rates in loess on the Chinese Loess Plateau, makes {sup 10}Be an especially valuable continental archive of paleoclimate and paleomagnetism, complementing marine and ice-core records. Here we provide in particular the most recent progress of {sup 10}Be tracer studies in Chinese loess, including the determination of the correct age of the Brunhes–Matuyama polarity reversal at 780 ± 3 ka B.P., in accord with marine and ice records, and quantitative reconstruction of 130-ka paleoprecipitation using {sup 10}Be from Chinese loess profiles.

  8. Location, Tilt, and Binding : A Molecular Dynamics Study of Voltage-Sensitive Dyes in Biomembranes

    NARCIS (Netherlands)

    Hinner, Marlon J.; Marrink, Siewert-J.; de Vries, Alex H.

    2009-01-01

    We present a molecular dynamics study on the interaction of styryl-type voltage-sensitive dyes with a lipid membrane. In this work, voltage-sensitive dyes are proposed as interesting model amphiphiles for biomolecular simulation, due to the wealth of biophysical and thermodynamical data available on

  9. The study of synthetic food dyes by positron annihilation lifetime spectroscopy.

    Science.gov (United States)

    Pivtsaev, A. A.; Razov, V. I.

    2015-06-01

    By method of positron annihilation lifetime spectroscopy (PALS), substances are food dyes were studied: E-102 (Tartrazine), E-124 (Ponso 4R), E 132 (Indigo carmine), E-133 (Brilliant Blue), E-151 (Black Shiny). They are examined for the presence of carcinogenic properties. The difference between dyes having explicit carcinogenic properties and mutagenic properties (non-explicit carcinogens) is established.

  10. Dyeing Properties of Basofil Fiber

    Institute of Scientific and Technical Information of China (English)

    JIANG Hong; DAI Jin-jin

    2002-01-01

    The structures and properties of Basofil fiber were studied using X- rays small angle diffraction analysis,differential- scanuing calorimeter and scanning electron microscopy. Disperse dyes, acid dyes and reactive dyes had been tried for dyeing Basefil fiber. It was shown disperse dyes were superior to other ones. The two series of high temperature dyes and low temperature dyes were compared for their suitability for Basofil fiber, and their dyeing behaviors were determined.

  11. Binding interaction of cationic phenazinium dyes with calf thymus DNA: a comparative study.

    Science.gov (United States)

    Sarkar, Deboleena; Das, Paramita; Basak, Soumen; Chattopadhyay, Nitin

    2008-07-31

    Absorption, steady-state fluorescence, steady-state fluorescence anisotropy, and intrinsic and induced circular dichroism (CD) have been exploited to explore the binding of calf thymus DNA (ctDNA) with three cationic phenazinium dyes, viz., phenosafranin (PSF), safranin-T (ST), and safranin-O (SO). The absorption and fluorescence spectra of all the three dyes reflect significant modifications upon interaction with the DNA. A comparative study of the dyes with respect to modification of fluorescence and fluorescence anisotropy upon binding, effect of urea, iodide-induced fluorescence quenching, and CD measurements reveal that the dyes bind to the ctDNA principally in an intercalative fashion. The effect of ionic strength indicates that electrostatic attraction between the cationic dyes and ctDNA is also an important component of the dye-DNA interaction. Intrinsic and induced CD studies help to assess the structural effects of dyes binding to DNA and confirm the intercalative mode of binding as suggested by fluorescence and other studies. Finally it is proposed that dyes with bulkier substitutions are intercalated into the DNA to a lesser extent.

  12. First principles DFT study of dye-sensitized CdS quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Kalpna; Singh, Kh. S. [Department of Physics, D. J. College, Baraut -250611, U.P. (India); Kishor, Shyam, E-mail: shyam387@gmail.com [Department of Chemistry, J. V. College, Baraut -250611, U.P. (India); Josefesson, Ida; Odelius, Michael [Fysikum, Albanova University Center, Stockholm University, S-106 91 Stockholm (Sweden); Ramaniah, Lavanya M. [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)

    2014-04-24

    Dye-sensitized quantum dots (QDs) are considered promising candidates for dye-sensitized solar cells. In order to maximize their efficiency, detailed theoretical studies are important. Here, we report a first principles density functional theory (DFT) investigation of experimentally realized dye - sensitized QD / ligand systems, viz., Cd{sub 16}S{sub 16}, capped with acetate molecules and a coumarin dye. The hybrid B3LYP functional and a 6−311+G(d,p)/LANL2dz basis set are used to study the geometric, energetic and electronic properties of these clusters. There is significant structural rearrangement in all the clusters studied - on the surface for the bare QD, and in the positions of the acetate / dye ligands for the ligated QDs. The density of states (DOS) of the bare QD shows states in the band gap, which disappear on surface passivation with the acetate molecules. Interestingly, in the dye-sensitised QD, the HOMO is found to be localized mainly on the dye molecule, while the LUMO is on the QD, as required for photo-induced electron injection from the dye to the QD.

  13. Isothermal, kinetic and thermodynamic studies on basic dye sorption ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-15

    Dec 15, 2009 ... obtained by diluting the dye stock solutions in accurate proportions to different ... with a 752 W Grating Spectrophotometer (Shanghai, China) and computing from the ... The ion exchange mechanism could be used to explain.

  14. Tracer Experimental Study of the Main Conveying Conduits of CCl4 Pollutant in the Qiligou Water Supply Resource

    Institute of Scientific and Technical Information of China (English)

    PEI Zong-ping; HAN Bao-ping; LIU Han-hu; LIANG Zhi; ZHOU Dong-lai; ZHU Xue-qiang

    2007-01-01

    The Ordovician karst groundwater in the Qiligou basin is an important water supply source. This groundwater has been seriously contaminated in recent years by CCl4 from a pesticide plant located in the recharge area. The highest concentration of CCl4 in the groundwater is 3909.2 μg/L. Large scale tracer experiments were carried out to study the conveying conduits for CCl4 in the basin on May 1-6, 2005. Nontoxic, edible glucose was used as a tracer and it was detected by spectrophotometric techniques. Well X-61, located near the pesticide plant in the southern recharge area of the basin, was employed for injecting the tracer. Ten wells widely located in the groundwater runoff area were used as observing and sampling wells. The results show that the migration of the pollutants is controlled by the water hydrodynamic field and by the development of karst conduits. The tracer did not enter the up-drainage wells, X-49 and X-47, near the injection point because the water levels at these wells are higher than at the injection point. The adjacent well X-62 is close to the injection site, but the tracer reached the well after eleven hours. Wells X-43, X-59, X-58, YY-1 and X-57, located in the syncline axis runoff area, are respectively 2.5, 3.5, 4.33, 4.38 and 5.44 kilometers from the injection site. The time for initial appearance of tracer was 4, 4, 2, 6 and 4 hours, respectively. The maximum runoff velocity (well X-58) is over two kilometers per hour, indicating that the karst conduits are well developed along the syncline basin axis. These conduits are the main conveying conduits for groundwater and CCl4. Closer wells were not necessarily the first to receive tracer. This shows the inhomogeneity in karst development which causes complex runoff, and pollutant migration, patterns.

  15. Spectral Studies of UV and Solar Photocatalytic Degradation of AZO Dye and Textile Dye Effluents Using Green Synthesized Silver Nanoparticles.

    Science.gov (United States)

    Mariselvam, R; Ranjitsingh, A J A; Mosae Selvakumar, P; Alarfaj, Abdullah A; Munusamy, Murugan A

    2016-01-01

    The photocatalytic degradation of the chemical dye AZO and dye effluents in different time duration has been investigated using biologically synthesized silver nanoparticles. Dye industry effluents and AZO dye undergo degradation to form harmless intermediate and colourless products following irradiation by UV and solar light in the presence of green synthesized silver nanoparticles. The degree of degradation was tested under the experimental conditions such as P(H), temperature, and absorbance of the dye in UV and solar light was measured. The degradation was higher in the UV light source than in the solar light source. Green synthesized silver nanoparticles in the UV light source were found to expedite the dye degradation process.

  16. Optical Absorption and Electron Injection of 4-(Cyanomethylbenzoic Acid Based Dyes: A DFT Study

    Directory of Open Access Journals (Sweden)

    Yuehua Zhang

    2015-01-01

    Full Text Available Density functional theory (DFT and time-dependent density functional theory (TDDFT calculations were carried out to study the ground state geometries, electronic structures, and absorption spectra of 4-(cyanomethylbenzoic acid based dyes (AG1 and AG2 used for dye-sensitized solar cells (DSSCs. The excited states properties and the thermodynamical parameters of electron injection were studied. The results showed that (a two dyes have uncoplanar structures along the donor unit and conjugated bridge space, (b two sensitizers exhibited intense absorption in the UV-Vis region, and (c the excited state oxidation potential was higher than the conduction band edge of TiO2 photoanode. As a result, a solar cell based on the 4-(cyanomethylbenzoic acid based dyes exhibited well photovoltaic performance. Furthermore, nine dyes were designed on the basis of AG1 and AG2 to improve optical response and electron injection.

  17. Physicochemical and Nonlinear Optical Properties of Novel Environmentally Benign Heterocyclic Azomethine Dyes: Experimental and Theoretical Studies.

    Science.gov (United States)

    Afzal, S M; Razvi, M A N; Khan, Salman A; Osman, Osman I; Bakry, Ahmed H; Asiri, Abdullah M

    2016-01-01

    Novel heterocyclic azomethine dyes were prepared by the reaction of anthracene-9-carbaldehyde with different heterocyclic amines under microwave irradiation. Structures of the azomethine dyes were confirmed by the elemental analysis, mass spectrometry and several spectroscopic techniques. We studied absorbance and fluorescence spectra of the azomethine dyes in various solvents. They are found to be good absorbers and emitters. We also report photophysical properties like, extinction coefficient, oscillator strength, stokes shift and transition dipole moment. This reflects physicochemical behaviors of synthesized dyes. In addition, their intramolecular charge transfer and nonlinear optical properties, supported by natural bond orbital technique, were also studied computationally by density functional theory. The negative nonlinear refractive index and nonlinear absorption coefficient were measured for these dyes using the closed and open aperture Z-scan technique with a continuous wave helium-neon laser. These are found to vary linearly with solution concentration.

  18. Physicochemical and Nonlinear Optical Properties of Novel Environmentally Benign Heterocyclic Azomethine Dyes: Experimental and Theoretical Studies

    Science.gov (United States)

    Afzal, S. M.; Razvi, M. A. N.; Khan, Salman A.; Osman, Osman I.; Bakry, Ahmed H.; Asiri, Abdullah M.

    2016-01-01

    Novel heterocyclic azomethine dyes were prepared by the reaction of anthracene-9-carbaldehyde with different heterocyclic amines under microwave irradiation. Structures of the azomethine dyes were confirmed by the elemental analysis, mass spectrometry and several spectroscopic techniques. We studied absorbance and fluorescence spectra of the azomethine dyes in various solvents. They are found to be good absorbers and emitters. We also report photophysical properties like, extinction coefficient, oscillator strength, stokes shift and transition dipole moment. This reflects physicochemical behaviors of synthesized dyes. In addition, their intramolecular charge transfer and nonlinear optical properties, supported by natural bond orbital technique, were also studied computationally by density functional theory. The negative nonlinear refractive index and nonlinear absorption coefficient were measured for these dyes using the closed and open aperture Z-scan technique with a continuous wave helium-neon laser. These are found to vary linearly with solution concentration. PMID:27631371

  19. Can nitro groups really anchor onto TiO2? Case study of dye-to-TiO2 adsorption using azo dyes with NO2 substituents.

    Science.gov (United States)

    Zhang, Lei; Cole, Jacqueline M

    2016-07-28

    The nitro group has recently been suggested as a new type of anchor for dye-sensitized solar cells (DSSCs) and has shown promising optoelectronic properties. Considering the excellent electron withdrawing ability of the nitro group and wider materials selection brought about by this substituent, it is helpful to evaluate the interfacial structures and photophysics of more organic dyes where NO2 poses as the dye-to-TiO2 anchor. A computational study on a family of azo dyes bearing a nitro group is presented, where the effect of certain side groups on their optical properties is examined. Both isolated dye molecules and dye/TiO2 nanocomposites are studied via density functional theory and time-dependent density functional theory, with complementary experimental UV/vis absorption spectroscopy and photovoltaic device testing. Results demonstrate that these nitro-containing dyes prefer a monodentate anchoring mode on a TiO2 cluster. These nitro dyes reveal weak, but non-negligible, adsorption onto TiO2; yet, very low photovoltaic performance once incorporated into a DSSC device. This poor delivery of nitro groups as DSSC anchors is ostensibly inconsistent with previous findings; but is rationalized via the "auxiliary anchor" concept.

  20. Study of the Optical and Physical Roles of a Dielectric Laser Dye Solvent Which Affects on the Dye Laser Operation

    Directory of Open Access Journals (Sweden)

    Riyad A.M. Ghazy

    2005-01-01

    Full Text Available It is well known that when the pump laser beam incidence on the laser dye liquid it will be absorbed. This absorption tends to heat the laser active medium, which is the laser dye solution. In view of this the correlated property of that active medium well change tends to shift the operated frequency and wavelength. Therefore, one of most interested dielectric, nonpolar, laser dye solvent was selected for this investigation, which is Benzene. A laser interferometer known as Mach Zhender Interferometer (MZI is constructed and used to measure the refractive index of the investigated solvent by counting the interfering fringes as a function of the angle of incidence of the incident laser beam. The temperature of that solvent is raised within the range 293-373 K by using a constructed heating system. The thermal behavior of the refractive index of Benzene is studied to estimate the thermo-optical coefficient of the refractive index, which is important to know the state convergence or divergence of the pump laser beam within the laser dye medium. Also, the dielectric constant of the dye solution is an important parameter for the laser operation. Therefore the dielectric constant and its thermal behavior of Benzene are calculated through the Maxwell’s relation to determine the thermal coefficient of the dielectric constant. The value of the number density which is equal the specific polarizability of the investigated solvent is estimated by using the obtained values of the refractive index and its variation with the temperature is studied too. Because the dependence of the mean polarizability of the dielectric constant through the Clausius-Mossotti relation the values of both mean polarizability and its thermal behavior are studied. In addition, since the molecular polarizability depends on the mean polarizability the value of it is determined. By using the values of mean polarizability the molecule radius is determined and using the Clausius

  1. A Preliminary Study on the Measurement of Sediment Concentration in Hill-Slope Runoff with an Electrolyte Tracer

    Directory of Open Access Journals (Sweden)

    Xiaonan Shi Fan Zhang

    2012-01-01

    Full Text Available Sediment concentration in hill-slope runoff is an important index for soil erosion. Developing a reliable and portable measuring system of sediment concentration is a core issue for soil and water conservation study, especially for the Tibetan Plateau under unfavorable climate and terrain conditions for field investigation. Challenges include uneven distribution of sediment across a runoff section as well as difficulty in detecting a wide range of particle sizes. An electrolyte tracer, with the advantage of uniform distribution and its widely used electric-conductivity sensor, can avoid the problems of direct measurement of sediment. A new measurement method of sediment concentration in runoff with an electrolyte tracer is proposed based on a premise that sediment concentration is closely correlated with hydrodynamic dispersion coefficient of solute in runoff. In this study, an experiment system of hill-slope runoff with an electrolyte tracer and sediments is first designed. Second, two model parameters in the advective-dispersive equation of solute transport, flow velocity and diffusion coefficient, are inversely estimated by calibrating the observed concentrations of an electrolyte tracer. And third, the relationship between sediment concentrations and hydrodynamic dispersion coefficients are defined through specified regression. As a result, a measurement system of sediment concentration in hill-slope runoff with an electrolyte tracer is primarily established by integrating the relationship of variables, experiment system, and model theory.

  2. Hydrodynamics of a commercial scale CFB boiler-study with radioactive tracer particles

    DEFF Research Database (Denmark)

    Lin, Weigang; Hansen, Peter F.B.; Dam-Johansen, Kim

    1999-01-01

    This paper presents the experimental results with radioactive tracer particles in an 80 MWth circulating fluidized-bed boiler. Batches of gamma-ray emitting tracer particles were injected into the standpipe. The response curves of the impulse injection were measured by a set of successive...

  3. Evaluation of the ERP dispersion model using Darlington tracer-study data. Report No. 90-200-K

    Energy Technology Data Exchange (ETDEWEB)

    Wright, S.C.

    1990-01-01

    In this study, site-boundary atmospheric dilution factors calculated by the atmospheric dispersion model used in the ERP (Emergency Response Planning) computer code were compared to data collected during the Darlington tracer study. The purpose of this comparison was to obtain estimates of model uncertainty under a variety of conditions. This report provides background on ERP, the ERP dispersion model and the Darlington tracer study. Model evaluation techniques are discussed briefly, and the results of the comparison of model calculations with the field data are presented and reviewed.

  4. Synthesis, spectroscopic, thermal and electrochemical studies on thiazolyl azo based disperse dyes bearing coumarin

    Science.gov (United States)

    Özkütük, Müjgan; İpek, Ezgi; Aydıner, Burcu; Mamaş, Serhat; Seferoğlu, Zeynel

    2016-03-01

    In this study, seven novel thiazolyl azo disperse dyes (6a-g) were synthesized and fully characterized by FT-IR, 1H NMR, 13C NMR, and mass spectral techniques. The electronic absorption spectra of the dyes in solvents of different polarities cover a λmax range of 404-512 nm. The absorption properties of the dyes changed drastically upon acidification. This was due to the protonation of the nitrogen in the thiazole ring, which in turn increased the donor-acceptor interplay of the π system in the dyes, and therefore increased the absorption properties of the prepared dyes. Thermal analysis showed that these dyes are thermal stable up to 269 °C. Additionally, the electrochemical behavior of the dyes (6a-g) were investigated using cyclic voltammetric and chronoamperometric techniques, in the presence of 0.10 M tetrabutylammonium tetrafluoroborate, in dimethylsulfoxide, at a glassy carbon electrode. The number of transferred electrons, and the diffusion coefficient were determined by electrochemical methods. The results showed that, for all the dyes, one oxidation peak and two reduction peaks were observed.

  5. Photodegradation of basic dyes using nanocomposite (Ag-zinc oxide-copper oxide and kinetic studies

    Directory of Open Access Journals (Sweden)

    Nasrin Khorshidi

    2016-05-01

    Full Text Available In this paper, Ag/ZnO/CuO nanocomposite (AZCN synthesized and its dye degradation ability in the presence of UV irradiation from colored wastewater was studied. The characteristics of AZCN were investigated using Fourier transform infrared (FTIR, scanning electron microscope (SEM and X-ray diffraction (XRD. The photocatalytic activity was evaluated by photodegradation of Basic Red 18 (BR18 and Basic Violet 16 (BV16 as a model contaminant. The effects of AZCN dosage, initial dye concentration and salt on dye degradation were investigated. Kinetics analysis indicated that the dye degradation rates could be approximated at pseudo-first order model. The results indicated that AZCN as a photocatalyst could be used to degrade dyes from wastewater.

  6. Perfluorocarbon Gas Tracer Studies to Support Risk Assessment Modeling of Critical Infrastructure Subjected to Terrorist Attacks

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Terry M.; Heiser, John H.; Watson, Tom; Allwine, K Jerry; Flaherty, Julia E.

    2006-05-06

    Development of real-time predictive modeling to identify the dispersion and/or source(s) of airborne weapons of mass destruction including chemical, biological, radiological, and nuclear material in urban environments is needed to improve response to potential releases of these materials via either terrorist or accidental means. These models will also prove useful in defining airborne pollution dispersion in urban environments for pollution management/abatement programs. Predicting gas flow in an urban setting on a scale of less than a few kilometers is a complicated and challenging task due to the irregular flow paths that occur along streets and alleys and around buildings of different sizes and shapes, i.e., “urban canyons”. In addition, air exchange between the outside and buildings and subway areas further complicate the situation. Transport models that are used to predict dispersion of WMD/CBRN materials or to back track the source of the release require high-density data and need defensible parameterizations of urban processes. Errors in the data or any of the parameter inputs or assumptions will lead to misidentification of the airborne spread or source release location(s). The need for these models to provide output in a real-time fashion if they are to be useful for emergency response provides another challenge. To improve the ability of New York City’s (NYC's) emergency management teams and first response personnel to protect the public during releases of hazardous materials, the New York City Urban Dispersion Program (UDP) has been initiated. This is a four year research program being conducted from 2004 through 2007. This paper will discuss ground level and subway Perfluorocarbon tracer (PFT) release studies conducted in New York City. The studies released multiple tracers to study ground level and vertical transport of contaminants. This paper will discuss the results from these tests and how these results can be used for improving

  7. Biochemical Studies in Some Indigenous Dye Yielding Plants of Manipur

    Directory of Open Access Journals (Sweden)

    Joylani D. SAIKHOM

    2013-08-01

    Full Text Available Ten natural dye yielding and two mordant plants were biochemically analyzed. Though natural dyes are widely used, information about the active principles responsible for dyeing is hardly available. In the present experiment, total chlorophyll, carotinoids, tannins, phenolics, flavonoids and curcumin were determined among the dye yielding plants, while K, S, P, Ca, Mg, Mn, Zn, Fe, Cu and Co were determined in the case of mordant plants. In Bixa orellana, used for yellow dyeing, the carotinoid content was 163.11 mg g-1 and in Clerodendrum chinense and Datura stramonium, which were used for green colouring, total chlorophyll content of 10.29 mg and 11.83 mg g-1 was recorded. Curcumin content responsible for orange colouring in Curcuma domestica was 27.7 mg g-1 while flavonoid content in Solanum nigrum and Terminalia chebula, which were used for brown, brown to black dyes was 24.89 and 21.73 mg g-1. Among the plants used for dyeing different colours, Punica granatum and Parkia timoriana were found to contain higher amounts of total phenols and bound phenols by recording 681.2 mg g-1 and 287.6 mg g-1 total phenols and 151.6 mg g-1 and 130.2mg g-1 bound phenols, while higher amounts of orthodihydric phenols and tannins were recorded in Punica granatum and Strobilanthes flaccidifolius by recording 20.11mg g-1 and 9.54mg g-1 orthodihydric phenols and 675.57mg g-1 and 648.12 mg g-1 tannins, respectively. In case of the plants used as mordant, higher contents of Ca, Mg, K, Zn, Fe and Mn were detected in Achyranthes aspera, while higher amounts of P, Fe and Cu were recorded in Garcinia xanthochymus.

  8. Isotope tracer study of hydrogen spillover on carbon-based adsorbents for hydrogen storage.

    Science.gov (United States)

    Lachawiec, Anthony J; Yang, Ralph T

    2008-06-17

    A composite material comprising platinum nanoparticles supported on molecular sieve templated carbon was synthesized and found to adsorb 1.35 wt % hydrogen at 298 K and 100 atm. The isosteric heat of adsorption for the material at low coverage was approximately 14 kJ/mol, and it approached a value of 10.6 kJ/mol as coverage increased for pressures at and above 1 atm. The increase in capacity is attributed to spillover, which is observed with the use of isotopic tracer TPD. IRMOF-8 bridged to Pt/C, a material known to exhibit hydrogen spillover at room temperature, was also studied with the hydrogen-deuterium scrambling reaction for comparison. The isotherms were reversible. For desorption, sequential doses of H2 and D2 at room temperature and subsequent TPD yield product distributions that are strong indicators of the surface diffusion controlled reverse spillover process.

  9. EXAFS, ab Initio Molecular Dynamics, and NICIS Spectroscopy Studies on an Organic Dye Model at the Dye-Sensitized Solar Cell Photoelectrode Interface.

    Science.gov (United States)

    Liu, Peng; Johansson, Viktor; Trilaksana, Herri; Rosdahl, Jan; Andersson, Gunther G; Kloo, Lars

    2017-06-14

    The organization of dye molecules in the dye layer adsorbed on the semiconductor substrate in dye-sensitized solar cells has been studied using a combination of theoretical methods and experimental techniques. The model system is based on the simple D-π-A dye L0, which has been chemically modified by substituting the acceptor group CN with Br (L0Br) to offer better X-ray contrast. Experimental EXAFS data based on the Br K-edge backscattering show no obvious difference between dye-sensitized titania powder and titania film samples, thus allowing model systems to be based on powder slurries. Ab initio molecular dynamic (aiMD) calculations have been performed to extract less biased information from the experimental EXASF data. Using the aiMD calculation as input, the EXAFS structural models can be generated a priori that match the experimental data. Our study shows that the L0Br dye adsorbs in the trans-L0Br configuration and that adsorption involves both a proximity to other L0Br dye molecules and the titanium atoms in the TiO2 substrate. These results indicate direct coordination of the dye molecules to the TiO2 surface in contrast to previous results on metal-organic dyes. The molecular coverage of L0Br on mesoporous TiO2 was also estimated using NICIS spectroscopy. The NICISS results emphasized that the L0Br dye on nanoporous titania mainly forms monolayers with a small contribution of multilayer coverage.

  10. Human biokinetic data and a new compartmental model of zirconium - A tracer study with enriched stable isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Greiter, Matthias B., E-mail: matthias.greiter@helmholtz-muenchen.de; Giussani, Augusto, E-mail: AGiussani@BfS.de; Hoellriegl, Vera, E-mail: vera.hoellriegl@helmholtz-muenchen.de; Li Weibo, E-mail: wli@helmholtz-muenchen.de; Oeh, Uwe, E-mail: uwe.oeh@helmholtz-muenchen.de

    2011-09-01

    Biokinetic models describing the uptake, distribution and excretion of trace elements are an essential tool in nutrition, toxicology, or internal dosimetry of radionuclides. Zirconium, especially its radioisotope {sup 95}Zr, is relevant to radiation protection due to its production in uranium fission and neutron activation of nuclear fuel cladding material. We present a comprehensive set of human data from a tracer study with stable isotopes of zirconium. The data are used to refine a biokinetic model of zirconium. Six female and seven male healthy adult volunteers participated in the study. It includes 16 complete double tracer investigations with oral ingestion and intravenous injection, and seven supplemental investigations. Tracer concentrations were measured in blood plasma and urine collected up to 100 d after tracer administration. The four data sets (two chemical tracer forms in plasma and urine) each encompass 105-240 measured concentration values above detection limits. Total fractional absorption of ingested zirconium was found to be 0.001 for zirconium in citrate-buffered drinking solution and 0.007 for zirconium oxalate solution. Biokinetic models were developed based on the linear first-order kinetic compartmental model approach used by the International Commission on Radiological Protection (ICRP). The main differences of the optimized systemic model of zirconium to the current ICRP model are (1) recycling into the transfer compartment made necessary by the observed tracer clearance from plasma, (2) different parameters related to fractional absorption for each form of the ingested tracer, and (3) a physiologically based excretion pathway to urine. The study considerably expands the knowledge on the biokinetics of zirconium, which was until now dominated by data from animal studies. The proposed systemic model improves the existing ICRP model, yet is based on the same principles and fits well into the ICRP radiation protection approach. - Research

  11. A spectroscopic study on the adsorption of cationic dyes into mesoporous AlMCM-41 materials

    Science.gov (United States)

    Zanjanchi, M. A.; Ebrahimian, A.; Alimohammadi, Z.

    2007-03-01

    Mesoporous materials loaded with dyes are of interest with respect to novel optical applications. The spectral behaviors of some dyes in these materials are considerably affected by the presence of surfactants. A comparative study has been carried out on the adsorption of the methylene blue, rhodamine 6G and thionine dyes into a surfactant-free and surfactant-containing mesoporous AlMCM-41. The ion exchange method has been employed for incorporation of the dye molecules into the structure of MCM-41. The exchangeable sites in the MCM-41 were generated prior to dye loading by isomorphous substitution of aluminum for silicon in the structure of the mesoporous material during the synthesis procedure. Diffuse reflectance measurements indicate adsorption of methylene blue and rhodamine 6G dye molecules into AlMCM-41 taken place via ion exchange at room temperature. The spectra show presence of monomer and dimer aggregates of the dyes established into the pores and surface of AlMCM-41. The ratio of dimer to monomer forms of rhodamine 6G incorporated in the surfactant-free and surfactant-containing AlMCM-41 is about one which is higher than those observed in aqueous solutions. The surfactant-containing AlMCM-41 induced destabilization and decomposition of methylene blue while uploading the dye. Degradation of this dye produces intermediate species identified as demethylated forms of methylene blue adsorbed on AlMCM-41. Our experiments revealed that kinetics of ion exchange for thionine dye is very slow at room temperature, but it become faster at higher temperatures. The spectral properties of thionine in AlMCM-41 are close to that of thionine in an aqueous solution, possibly due to high pore space in a mesoporous molecular sieve. No adsorption of thionine was observed for surfactant-containing AlMCM-41 even at higher temperatures.

  12. 染料示踪法联合荧光示踪法提高乳腺癌前哨淋巴结活检术成功率%Success Rate of Sentinel Lymph Node Biopsy in Breast Cancer Increased by Combined Tracer Method of Fluorescence and Dye

    Institute of Scientific and Technical Information of China (English)

    崔嵘嵘; 林晓燕; 许诚; 胡贇宏; 王铮元; 蔡丰丰

    2016-01-01

    杂作用后,采用染料示踪法联合荧光示踪法 SLNB 成功率高于采用染料示踪法(χ2MH=26.686,P ﹤0.001,ORMH =3.928)。Logistic 回归分析结果显示,示踪法、BMI、年龄是 SLNB 结果的影响因素(P﹤0.05)。Logistic 回归模型分类预测准确率为80.2%。结论染料示踪法联合荧光示踪法可有效提高乳腺癌 SLNB 成功率,值得临床推荐使用。%Background The sentinel lymph node biopsy(SLNB)of breast cancer is gaining increased attention in recent years,and the choosing of tracer is of great importance in its success rate. Objective To evaluate the clinical effectiveness and application value of the combined tracer method of fluorescence and dye in SLNB of breast cancer. Methods According to the inclusion criteria of the study,449 patients with primarily invasive breast cancer,who received treatment in Department of Breast Surgery of Yangpu Hospital,Tongji University from January 2010 to September 2015,were selected as research objects. Patients were divided into group A(226 patients with dye tracer method)and group B(223 patients with the combined tracer method of fluorescence and dye)by random number table method. The general information〔 including age,body mass index(BMI)〕of patients were collected,the success rate of patients' SLNB were calculated. Stratified analysis of patients were made based on their BMI(≤22. 5 kg/ m2 and ﹥ 22. 5 kg/ m2 )and age(≤55 and ﹥ 55). Results BMI and age in group A were less than those in group B(P ﹤ 0. 05). Among the 223 patients(BMI≤22. 5 kg/ m2 ),the success rate of SLNB with combined tracer method of fluorescence and dye〔94. 7%(108 / 114)〕was higher than that of SLNB with dye tracer method〔78. 0%(85 / 109)〕〔OR = 5. 082,95% CI(1. 988,12. 993)〕. Among the 226 patients(BMI ﹥ 22. 5 kg/ m2 ),the success rate of SLNB with combined tracer method of fluorescence and dye〔85. 3%(93 / 109)〕was higher than that of SLNB with dye

  13. Gamma Radiolysis Studies of Aqueous Solution of Brilliant Green Dye

    Directory of Open Access Journals (Sweden)

    D. V. Parwate

    2011-01-01

    Full Text Available The effect of γ–radiation on colour intensity of aqueous solution of Brilliant Green has been investigated at two different concentrations. The degradation of Brilliant Green (BG has also been investigated in presence of suspended ZnO, by adding different amounts of ZnO. Simultaneously the conductance and pH of each solution system were measured before and after γ-irradiation. All the γ–irradiations were performed at a dose rate of 0.60 kGyhr-1 in GC-900. The maximum dose required for the complete degradation of the dye was found to be 0.39 kGy. G(-dye values were found to decrease with increase in gamma dose and were in the range 4.26 - 12.81. The conductance (7.6 - 25.3 μS and pH values increased marginally with dose for both the concentrations. The rate of decolouration was found to be high at lower doses and the efficiency of dye removal was higher at low concentration of the dye. This may be attributed to the presence of reaction by-products from the destruction of parent compound build up and compete for reaction intermediate species. The rate of reaction and rate constants were calculated and it was found that the degradation reaction follows first order kinetics. It was found that the decolouration percentage was more in dye systems in absence of ZnO.

  14. THERMOCHROMIC EFFECTS OF LEUCO DYES STUDIED IN POLYPROPYLENE

    Institute of Scientific and Technical Information of China (English)

    Arno Seeboth; Detlef L(o)tzsch; Elvira Potechius; Renate Vetter

    2006-01-01

    A series of thermochromic polypropylene foils were prepared by embedding various leuco dye-developer-solvent systems in the polymer matrix. Bisphenol A, laurylgallate, ethylgallate and p-hydroxybenzoic acid methyl ester were used as developers, crystal violet lactone and 3,3-bis-(1-n-butyl-2-methyl-3-indolyl)-phthalide as dyes and 1-octanoic acid methyl ester as solvent. The molar ratio between the three components of the investigated leuco dye-developer-solvent systems was kept constant. All obtained polypropylene foils exhibit an excellent thermochromic behavior. The foils, prepared by extrusion technology, switch from color to colorless with increasing temperature. The influence of molecular structure of the developer on the intensity of the colored state and the influence of a developer-surfactant complex on the resulting thermochromic properties were investigated. The results are presented and discussed in detail according to a molecular model suggesting that the ring-opening process of the leuco dye is triggered by the formation of dye-developer complexes via H-bondings.

  15. Comparative study of gas diffusion in subsurface using dual-gas tracer SF6 and halon 1211

    Directory of Open Access Journals (Sweden)

    Wang Weixian

    2016-01-01

    Full Text Available Field experiment and soil column test were performed to study the gas diffusion in the soil subsurface using dual-gas tracer SF6 and halon 1211. Gas samples collected from pre-set sampling sites were measured. These two tracer gases showed the similar trend. At the different directions from injecting site, concentrations increased rapidly at the beginning, the peak value concentration of SF6 was higher than that of halon 1211, implied SF6 diffuse further. At the different depth from injecting site, tracer gases preferred to transport horizontal or downwards rather than upwards, meant gravity settling was an important factor affecting the gas diffusion. The effect of temperature and water content on the gas diffusion revealed that gases migrated fast obviously with the temperature increase, the change of water content had influence slightly. Gas desorption test indicated that much more halon 1211 was adsorbed on the soil, which led the diffusion process slow down.

  16. Conducting Graduate Tracer Studies for Quality Assurance in East African Universities: A Focus on Graduate Students Voices on Quality Culture

    Science.gov (United States)

    Badiru, Egesah Omar; Wahome, Mary

    2016-01-01

    The purpose of this paper is to propose a guide for graduate trace studies (GTS) to be adopted by universities and other higher education institutions (HEIs) in East Africa. Their essential role notwithstanding, graduate tracer studies present viable opportunities through which quality assurance (QA) can be institutionalized and mainstreamed in…

  17. The fluorescent tracer experiment on Holiday Beach near Mugu Canyon, Southern California

    Science.gov (United States)

    Kinsman, Nicole; Xu, J. P.

    2012-01-01

    After revisiting sand tracer techniques originally developed in the 1960s, a range of fluorescent coating formulations were tested in the laboratory. Explicit steps are presented for the preparation of the formulation evaluated to have superior attributes, a thermoplastic pigment/dye in a colloidal mixture with a vinyl chloride/vinyl acetate copolymer. In September 2010, 0.59 cubic meters of fluorescent tracer material was injected into the littoral zone about 4 kilometers upcoast of Mugu submarine canyon in California. The movement of tracer was monitored in three dimensions over the course of 4 days using manual and automated techniques. Detailed observations of the tracer's behavior in the coastal zone indicate that this tracer successfully mimicked the native beach sand and similar methods could be used to validate models of tracer movement in this type of environment. Recommendations including how to time successful tracer studies and how to scale the field of view of automated camera systems are presented along with the advantages and disadvantages of the described tracer methodology.

  18. Personal hair dye use and the risk of bladder cancer: a case–control study from The Netherlands

    NARCIS (Netherlands)

    Ros, M.; Gago-Dominguez, M.; Bueno de Mesquita, H.B.; Kampman, E.; Vermeulen, S.H.; Kiemeney, L.A.

    2012-01-01

    Background - Several studies have suggested an increased risk of bladder cancer among hairdressers, who are occupationally exposed to hair dyes. There has also been concern about a possible increased risk of bladder cancer among users of hair dyes. However, the association between personal hair dye

  19. Personal hair dye use and the risk of bladder cancer : a case-control study from The Netherlands

    NARCIS (Netherlands)

    Ros, Martine M.; Gago-Dominguez, Manuela; Aben, Katja K. H.; Bueno-de-Mesquita, H. Bas; Kampman, Ellen; Vermeulen, Sita H.; Kiemeney, Lambertus A.

    2012-01-01

    Several studies have suggested an increased risk of bladder cancer among hairdressers, who are occupationally exposed to hair dyes. There has also been concern about a possible increased risk of bladder cancer among users of hair dyes. However, the association between personal hair dye use and bladd

  20. Personal hair dye use and the risk of bladder cancer: a case-control study from The Netherlands

    NARCIS (Netherlands)

    Ros, M.M.; Gago-Dominguez, M.; Aben, K.K.; Bueno-De-Mesquita, H.B.; Kampman, E.; Vermeulen, S.; Kiemeney, L.A.

    2012-01-01

    BACKGROUND: Several studies have suggested an increased risk of bladder cancer among hairdressers, who are occupationally exposed to hair dyes. There has also been concern about a possible increased risk of bladder cancer among users of hair dyes. However, the association between personal hair dye u

  1. Personal hair dye use and the risk of bladder cancer: a case–control study from The Netherlands

    NARCIS (Netherlands)

    Ros, M.; Gago-Dominguez, M.; Bueno de Mesquita, H.B.; Kampman, E.; Vermeulen, S.H.; Kiemeney, L.A.

    2012-01-01

    Background - Several studies have suggested an increased risk of bladder cancer among hairdressers, who are occupationally exposed to hair dyes. There has also been concern about a possible increased risk of bladder cancer among users of hair dyes. However, the association between personal hair dye

  2. Synthesis and characterization of environmentally friendly fluorescent particle tracers

    Science.gov (United States)

    Tauro, Flavia; Porfiri, Maurizio; Rapiti, Emiliano; Grimaldi, Salvatore

    2013-04-01

    Tracers are widely used in experimental fluid mechanics and hydrology to investigate complex flows and water cycle processes. Commonly used tracers include dyes, artificial tracers, naturally occurring isotopes and chemicals, microorganisms, and DNA-based systems. Tracers should be characterized by low detection limits and high accuracy in following water paths and flow structures. For natural studies, tracers are also expected to be nontoxic and with low sorption affinity to natural substrates to minimize losses in the environment. In this context, while isotopes are completely natural, their use in field studies is limited by their ubiquity and, therefore, by the high uncertainty in data processing methodologies. Further, the use of dyes and artificial tracers can be hampered by extremely low detection limits due to dilution in natural streams and microorganisms, while DNA-based system may require physical sampling and time-consuming functionalization and detection procedures. In this work, we present the synthesis and characterization of fluorescent beads incorporating an eco-compatible fluorophore for environmental and laboratory applications. The particles are synthesized from natural beeswax through an inexpensive thermal procedure and can be engineered to present variable densities and diameters. A thorough characterization of their surface morphology at the nanoscale, crystal structure and size, chemical composition, and dye incorporation into the beeswax matrix is described by using a wide array of microscopy techniques. In addition, the particle fluorescence response is studied by performing excitation and emission scans on melted beeswax bead samples. The feasibility of using the synthesized particles in environmental settings is assessed through the design of ad-hoc weathering agent experiments where the beads are exposed to high energy radiation and hot water. Further, a proof of concept test is described to understand the particles' potential as a

  3. Removal of Crystal Violet dye from aqueous solution using water hyacinth: Equilibrium, kinetics and thermodynamics study

    Directory of Open Access Journals (Sweden)

    M. Rajeswari Kulkarni

    2017-03-01

    Full Text Available Effluent water from dyeing industries has now for long been a taxing issue. Of the various dyes which are extremely toxic, Crystal Violet which is used in the dyeing industry is known for its mutagenic and mitotic poisoning nature. Water hyacinth (Eichhornia crassipes is a perennial aquatic plant notorious for its rapid invasive growth on the surface of water bodies causing ill-effects on the biodiversity. The potential of powdered roots of water hyacinth was studied for decolorization of Crystal Violet dye. Influence of parameters such as initial pH (2.0–10.0, initial dye concentration (100–500 ppm, biosorbent dosage (0.5–5 g/l, contact time (10–240 min and temperature (300–323 K were examined. Maximum removal of dye was observed at pH 7.8. The obtained data were fit into different kinetic models and the biosorption was found to follow pseudo second order kinetic model. The Langmuir monolayer biosorption capacity of water hyacinth was estimated as 322.58 mg/g. The study has demonstrated water hyacinth as a potential low cost biosorbent for effective removal of Crystal Violet dye from aqueous solution.

  4. A Study of Mixed Vegetable Dyes with Different Extraction Concentrations for Use as a Sensitizer for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Kun-Ching Cho

    2014-01-01

    Full Text Available Two vegetable dyes are used for the study: chlorophyll dye from sweet potato leaf extract and anthocyanin dye from extracts of blueberry, purple cabbage, and grape. The chlorophyll and anthocyanin dyes are blended in a cocktail in equal proportions, by volume. This study determines the effect of different extraction concentrations and different vegetable dyes on the photoelectric conversion efficiency of dye-sensitized solar cells. In order to make the electrode for the experiments, P25 TiO2 powder was coated on the ITO conducting surface, using a medical blade, to form a thin film with a thickness of around 35 μm. The experimental results show that the cocktail dye blended using extracts of sweet potato leaf and blueberries, in the volumetric proportion 1 : 1, at a weight concentration of 40%, using an extraction temperature of 50°C and an extraction heating time of 10 min produces the greatest photoelectric conversion efficiency (η of up to 1.57%, an open-circuit voltage (VOC of 0.61 V, and a short-circuit current density (JSC of 4.75 mA/cm2.

  5. Bacteriophages as surface and ground water tracers

    Directory of Open Access Journals (Sweden)

    P. Rossi

    1998-01-01

    Full Text Available Bacteriophages are increasingly used as tracers for quantitative analysis in both hydrology and hydrogeology. The biological particles are neither toxic nor pathogenic for other living organisms as they penetrate only a specific bacterial host. They have many advantages over classical fluorescent tracers and offer the additional possibility of multi-point injection for tracer tests. Several years of research make them suitable for quantitative transport analysis and flow boundary delineation in both surface and ground waters, including karst, fractured and porous media aquifers. This article presents the effective application of bacteriophages based on their use in differing Swiss hydrological environments and compares their behaviour to conventional coloured dye or salt-type tracers. In surface water and karst aquifers, bacteriophages travel at about the same speed as the typically referenced fluorescent tracers (uranine, sulphurhodamine G extra. In aquifers of interstitial porosity, however, they appear to migrate more rapidly than fluorescent tracers, albeit with a significant reduction in their numbers within the porous media. This faster travel time implies that a modified rationale is needed for defining some ground water protection area boundaries. Further developments of other bacteriophages and their documentation as tracer methods should result in an accurate and efficient tracer tool that will be a proven alternative to conventional fluorescent dyes.

  6. Bacteriophages as surface and ground water tracers

    Science.gov (United States)

    Rossi, P.; Dörfliger, N.; Kennedy, K.; Müller, I.; Aragno, M.

    Bacteriophages are increasingly used as tracers for quantitative analysis in both hydrology and hydrogeology. The biological particles are neither toxic nor pathogenic for other living organisms as they penetrate only a specific bacterial host. They have many advantages over classical fluorescent tracers and offer the additional possibility of multi-point injection for tracer tests. Several years of research make them suitable for quantitative transport analysis and flow boundary delineation in both surface and ground waters, including karst, fractured and porous media aquifers. This article presents the effective application of bacteriophages based on their use in differing Swiss hydrological environments and compares their behaviour to conventional coloured dye or salt-type tracers. In surface water and karst aquifers, bacteriophages travel at about the same speed as the typically referenced fluorescent tracers (uranine, sulphurhodamine G extra). In aquifers of interstitial porosity, however, they appear to migrate more rapidly than fluorescent tracers, albeit with a significant reduction in their numbers within the porous media. This faster travel time implies that a modified rationale is needed for defining some ground water protection area boundaries. Further developments of other bacteriophages and their documentation as tracer methods should result in an accurate and efficient tracer tool that will be a proven alternative to conventional fluorescent dyes.

  7. Numerical study of tracers transport by a mesoscale convective system over West Africa

    Directory of Open Access Journals (Sweden)

    J.-P. Pinty

    2011-05-01

    Full Text Available A three-dimensional cloud-resolving model is used to investigate the vertical transport from the lower to the upper troposphere in a mesoscale convective system (MCS that occurred over Niger on 15 August 2004. The redistribution of five passive tracers initially confined in horizontally homogeneous layers is analyzed. The monsoon layer tracer (0–1.5 km is the most efficiently transported in the upper troposphere with concentrations 3 to 4 times higher than the other tracers in the anvil. On the contrary the African Easterly Jet tracer (~3 km has the lowest contribution above 5 km. The vertical profiles of the mid-troposphere tracers (4.5–10 km in the MCS exhibit two peaks: one in their initial layers, and the second one at 13–14 km altitude, underlying the importance of mid-tropospheric air in feeding the upper troposphere. Mid-tropospheric tracers also experience efficient transport by convective downdrafts with a consequent increase of their concentrations at the surface. The concentration of the upper troposphere–lower stratosphere tracer exhibits strong gradients at the edge of the cloud, meaning almost no entrainment of this tracer into the cloud. No downward transport from the upper troposphere is simulated below 5 km. A proxy for lightning produced NOx is transported preferentially in the forward anvil in the upper troposphere. Additionally, lateral inflows significantly contribute to the updraft and downdraft airflows emphasizing the three-dimensional structure of the West African MCSs.

  8. Optimization and kinetic studies on treatment of textile dye wastewater using Pleurotus floridanus

    Science.gov (United States)

    Sathian, S.; Radha, G.; Shanmugapriya, V.; Rajasimman, M.; Karthikeyan, C.

    2013-03-01

    Treatment of textile dye wastewater was carried using Pleurotus floridanus in a batch reactor. Response surface methodology (RSM) was used to optimize the process parameters like pH, temperature, agitation speed and dye wastewater concentration for the decolorization of textile dye wastewater. The optimum conditions for the maximum decolorization was: pH 6.6, temperature 28.8 °C, agitation speed 183 rpm and dye wastewater concentration 1:2. From the results it was found that, the linear effect of agitation speed and initial textile dye wastewater concentration were more significant than other factors for the textile dye wastewater treatment. At these optimized conditions, the maximum decolorization and COD reduction was found to be 71.2 and 80.5 %, respectively. Kinetics of textile dye degradation process was studied by various models like first order, diffusional and Singh model. From the results it was found that the degradation follows first order model with R 2 value of 0.9550.

  9. Study on the photoreductive decolorization of azo dyes by sulfite aqua

    Science.gov (United States)

    Liu, Wei; Hu, Wenna; Liu, Jian

    2017-01-01

    In this paper, the decolorization of a series of azo dyes by sulfite aqua was studied under UV light irradiation and in the dark, respectively. Soluble azo dyes were easily decolorized with high decolorization efficiency under UV light irradiation, while their decolorization efficiency was much lower in the dark. The ultraviolet light is of the utmost importance for the rapid decolorization of azo dyes. As for the 10 mg/L Methyl Orange and Congo Red exposed to UV light, the decolorization efficiency reaches up to 95.9% in 10 min and 95.8% in 20 min, using 1.0 g/L and 8.0 g/L sodium sulfite, respectively. Whereas, for the same concentration of azo dyes and sodium sulfite, the decolorization efficiency of Methyl Orange and Congo Red is only 13.8% and 25.6%, respectively, even if they are laid in the dark with sodium sulfite for 48 h. The decolorization process of Methyl Orange and Congo Red follows the first order rate kinetics. The location of absorption peak in the visible region is blue-shifted in the course of the reaction. It is proposed that the decolorization of azo dyes is a reduction reaction. The chromophore of azo dye reacts with hydrogen and results in their decolorization. The possible mechanisms of the reductive decolorization of azo dyes were also discussed.

  10. The Experience of Receiving and Then Losing a Scholarship: A Tracer Study of Secondary School Scholarship Recipients in Uganda

    Science.gov (United States)

    Watson, Cathy; Chapman, David W.; Okurut, Charles Opolot

    2014-01-01

    This study reports findings of a tracer that investigated differences in the profile and subsequent experiences of scholarship recipients in Uganda who were able to complete the lower secondary school cycle (O level) without interruption (N = 174) and those that dropped out before completing their O-level cycle (N = 51), thereby losing their…

  11. Spectral and Fluorescent Studies of the Interaction of an Anionic Oxacarbocyanine Dye with Bovine Serum Albumin

    Science.gov (United States)

    Pronkin, P. G.; Tatikolov, A. S.

    2017-01-01

    The influence of the formation of noncovalent intermolecular complexes with bovine serum albumin (BSA) on the spectral and fluorescent properties of the anionic oxacarbocyanine dye 3,3'-di-(γ-sulfopropyl)-5,5'-diphenyl-9-ethyloxacarbocyanine betaine (OCC) was studied. Binding of OCC to BSA increased significantly the dye fluorescence. Changes in the absorption and fluorescence spectra of OCC upon interaction with BSA argued in favor of a shift of the dye cis-trans equilibrium in the complex. The effects of adding albumin-denaturing compounds (urea, sodium dodecyl sulfate) on the spectral and fluorescent properties of the dye in the OCC-BSA complex were studied. It was concluded that OCC can act as a probe for albumins and can be used to study protein denaturing.

  12. Hair dyeing, hair washing and hair cortisol concentrations among women from the healthy start study

    DEFF Research Database (Denmark)

    Kristensen, Sheila K.; Larsen, Sofus C.; Olsen, Nanna J.

    2017-01-01

    Background: Hair cortisol concentration (HCC) has been suggested as a promising marker for chronic stress. However, studies investigating the influence of hair dyeing and hair washing frequency on HCC have shown inconsistent results. Objective: To examine associations between HCC and hair dyeing...... status or weekly hair washing frequency among women. Methods: This cross-sectional study was based on data from 266 mothers participating in the Healthy Start intervention study. HCC was measured in the proximal end of the hair (1–2 cm closest to the scalp) while hair dyeing status, frequency of hair...... washing and covariates were reported by the women. Linear regression analyses were applied to assess the associations between HCC and hair dyeing or weekly frequency of hair washing. Results: No statistically significant difference (p = 0.91) in HCC was found between women who dyed hair (adjusted mean...

  13. Chemical Tracer Methods: Chapter 7

    Science.gov (United States)

    Healy, Richard W.

    2017-01-01

    Tracers have a wide variety of uses in hydrologic studies: providing quantitative or qualitative estimates of recharge, identifying sources of recharge, providing information on velocities and travel times of water movement, assessing the importance of preferential flow paths, providing information on hydrodynamic dispersion, and providing data for calibration of water flow and solute-transport models (Walker, 1998; Cook and Herczeg, 2000; Scanlon et al., 2002b). Tracers generally are ions, isotopes, or gases that move with water and that can be detected in the atmosphere, in surface waters, and in the subsurface. Heat also is transported by water; therefore, temperatures can be used to trace water movement. This chapter focuses on the use of chemical and isotopic tracers in the subsurface to estimate recharge. Tracer use in surface-water studies to determine groundwater discharge to streams is addressed in Chapter 4; the use of temperature as a tracer is described in Chapter 8.Following the nomenclature of Scanlon et al. (2002b), tracers are grouped into three categories: natural environmental tracers, historical tracers, and applied tracers. Natural environmental tracers are those that are transported to or created within the atmosphere under natural processes; these tracers are carried to the Earth’s surface as wet or dry atmospheric deposition. The most commonly used natural environmental tracer is chloride (Cl) (Allison and Hughes, 1978). Ocean water, through the process of evaporation, is the primary source of atmospheric Cl. Other tracers in this category include chlorine-36 (36Cl) and tritium (3H); these two isotopes are produced naturally in the Earth’s atmosphere; however, there are additional anthropogenic sources of them.

  14. Simulation of soluble waste transport and buildup in surface waters using tracers

    Science.gov (United States)

    Kilpatrick, F.A.

    1993-01-01

    Soluble tracers can be used to simulate the transport and dispersion of soluble wastes that might have been introduced or are planned for introduction into surface waters. Measured tracer-response curves produced from the injection of a known quantity of soluble tracer can be used in conjunction with the superposition principle to simulate potential waste buildup in streams, lakes, and estuaries. Such information is particularly valuable to environmental and water-resource planners in determining the effects of proposed waste discharges. The theory, techniques, analysis, and presentation of results of tracer-waste simulation tests in rivers, lakes, and estuaries are described. This manual builds on other manuals dealing with dye tracing by emphasizing the expanded use of data from time-of-travel studies.

  15. PERFLUOROCARBON GAS TRACER STUDIES TO SUPPORT RISK ASSESSMENT MODELING OF CRITICAL INFRASTRUCTURE SUBJECTED TO TERRORIST ATTACKS.

    Energy Technology Data Exchange (ETDEWEB)

    SULLIVAN, T.M.; HEISER, J.; WATSON, T.; ALLWINE, K.J.; FLAHERTY, J.E.

    2006-05-06

    Development of real-time predictive modeling to identify the dispersion and/or source(s) of airborne weapons of mass destruction including chemical, biological, radiological, and nuclear material in urban environments is needed to improve response to potential releases of these materials via either terrorist or accidental means. These models will also prove useful in defining airborne pollution dispersion in urban environments for pollution management/abatement programs. Predicting gas flow in an urban setting on a scale of less than a few kilometers is a complicated and challenging task due to the irregular flow paths that occur along streets and alleys and around buildings of different sizes and shapes, i.e., ''urban canyons''. In addition, air exchange between the outside and buildings and subway areas further complicate the situation. Transport models that are used to predict dispersion of WMD/CBRN materials or to back track the source of the release require high-density data and need defensible parameterizations of urban processes. Errors in the data or any of the parameter inputs or assumptions will lead to misidentification of the airborne spread or source release location(s). The need for these models to provide output in a real-time fashion if they are to be useful for emergency response provides another challenge. To improve the ability of New York City's (NYC's) emergency management teams and first response personnel to protect the public during releases of hazardous materials, the New York City Urban Dispersion Program (UDP) has been initiated. This is a four year research program being conducted from 2004 through 2007. This paper will discuss ground level and subway Perfluorocarbon tracer (PFT) release studies conducted in New York City. The studies released multiple tracers to study ground level and vertical transport of contaminants. This paper will discuss the results from these tests and how these results can be used

  16. Synthesis and physicochemical studies of some new quinolinoxazine pentamethine cyanine dyes

    Directory of Open Access Journals (Sweden)

    R.M. Abd El-Aal

    2017-01-01

    Full Text Available Polymethine cyanine dyes belong to a well-known class of organic compounds, which have been used in photography and as information storage in laser technology. A series of novel cyanine dyes were synthesized through the formylation of quinolinium[b,c]1,4-oxazine-chloride salt 1. Reaction of compound 2-chloro-3-formyl-quinolinium[b,c]1,4-oxazine-chloride salt 2 with different molar ratios of 2(4-methyl substituted heterocyclic in basic catalysis afforded the corresponding 2-chloroquinolinium[b,c]1,4-oxazine-chloride salt-3[2(4]-dimethine (3a–c, quinolinium[b,c]-1,4-oxazinechloride salt-2,3[2(4]-pentamethine (4a–c and quinolino[b,c]1,4-oxazine-6yl[2(4]-monomethine-/2,3[2(4]-pentamethine cyanine dyes (5a–c respectively. The structure of the dyes was characterized by elemental analysis, visible absorption, fluorescence emission, IR, 1H-NMR and mass spectroscopy. The correlations between the structure and properties of these dyes have been studied. A comparison of the visible absorption maxima between compounds 3b, 4b and 5b showed that asymmetrical mono-pentamethine cyanine dye 5b reveals a bathochromic shift than both dimethine 3b and pentamethine cyanine dyes 4b. This could be attributed to the more extensive π-conjugation and increasing number of methine groups in asymmetric pentamethine. All the observations and analytical spectra in this paper support the syntheses of new di-, penta- and mono-/pentamethine cyanine dyes. The absorption spectra of dyes were investigated in organic solvents. The results indicated that the excitation for their colour is a simple charge-transfer from oxygen atom of oxazine nucleus and/or nitrogen atom of pyridine (quinoline nucleus to N-quaternary salts in di-, penta- and mono-/pentamethine cyanine dyes respectively. These dyes showed positive solvatochromism with increased solvent polarity, which depends on the structure and the type of dye.

  17. Use of /sup 75/Se tracer and autoradiographic techniques in the study of schistosomiasis

    Energy Technology Data Exchange (ETDEWEB)

    Chandiwana, S.K. (New York State Veterinary Coll., Ithaca, NY (USA))

    1988-12-01

    The paper provides an overview of recent studies on the use of /sup 75/Se to tag larval schistosomes and to monitor their migration and distribution patterns in naive mice and those previously exposed to cercariae. The principles and techniques of radioassay and autoradiography in studying various aspects of /sup 75/Se-labelled larval schistosomes are described. The main shortcoming of radioassay in monitoring location and movement of labelled schistosomula is that some of the label dissociates from the schistosomula and accumulates in host tissues, notably the liver. Dissociated label is indistinguishable from schistosomula-bound label making monitoring of parasite migration extremely difficult. This difficulty is overcome by compressed tissue autoradiography where labelled schistosomula can be seen as reduced silver foci on an autoradiographic film, whereas dissociated label is too diffusely distributed to produce such reduced silver foci. Furthermore, using autoradiography, quantitative information on parasite migration in normal and immunized laboratory animals can be obtained that would be impossible using traditional recovery techniques. In addition to using /sup 75/Se tracer in migration studies, the radio-isotope has potential for elucidating various aspects of schistosome transmission ecology and snail population dynamics in natural waters. (author).

  18. 11C-harmine as a potential PET tracer for ductal pancreas cancer: in vitro studies.

    Science.gov (United States)

    Herlin, G; Persson, B; Bergström, M; Långström, B; Aspelin, P

    2003-04-01

    Our objective was to find a tracer in diagnosing human pancreatic cancer using positron emission tomography (PET). For this purpose in vitro test of pancreatic tissues with autoradiography was used. Autoradiography was performed with (11)C-harmine (a MAO-A-inhibitor) with and without competitive inhibition. Tissue preparations were obtained from normal human pancreas and pancreatic cancer. The uptake was compared with rat brain or pig brain, tissues with high expression of MAO-A. Nine autoradiography studies on 16 samples from five different human pancreatic cancers gave a significant level of specific binding of (11)C-harmine in 13, and 3 samples did not give a significant level of specific binding of (11)C-harmine. All 16 samples were analysed with autoradiography. Compared with rat brain, the uptake in the human cancers varied between 9 and 43% except for one tissue preparation which had a too low value for measurement. This study shows expression of MAO-A in human pancreatic cancer. This is readily characterised in vitro. The potential use of (11)C-harmine in the diagnosis of pancreatic cancer using PET might be limited, but further PET studies are necessary.

  19. Tracer-based studies of soil water movement in semi-arid forests of New Mexico

    Science.gov (United States)

    Newman, Brent D.; Campbell, Andrew R.; Wilcox, Bradford P.

    1997-09-01

    The related issues of water movement and contaminant transport in arid and semi-arid environments have generated considerable interest and concern in the last few decades. Essential to understanding these issues is knowledge of how water moves through the soils that form the uppermost part of the vadose zone. The use of tracers, both natural and artificially introduced, is proving to be an effective method for gaining such knowledge in dry regions, where investigation by other means is difficult. In this study, natural stable-isotope and chloride tracers were used to investigate water movement in the soils of a piñon-juniper woodland and of a ponderosa pine forest on the Pajarito Plateau in northern New Mexico. The objectives were to (1) estimate and compare near-surface flux rates and evaluate the importance of evaporation in the two communities, and (2) determine to what extent differences in flux rates and evaporation are due to differences in plant cover and/or soil hydraulic properties. The results of this study will aid in evaluating the potential for contaminant mobility in semi-arid systems such as the Pajarito Plateau and, in addition, will increase understanding of nutrient distributions and plant water use in semi-arid environments. The stable-isotope data indicate a similarity between the piñon-juniper and ponderosa communities with respect to evaporation: in both, it is restricted mainly to the upper 10 cm of soil. Chloride profiles from the two communities, on the other hand, show a distinct difference with respect to downward fluxes: in the ponderosa pine forest, these fluxes (≈0.02 cm year -1) are an order of magnitude lower than those in the piñon-juniper woodland (≈0.2 cm year -1), even though total precipitation is about 4 cm year -1 higher in the ponderosa pine forest. This difference, however, appears to be related not to plant cover, but to differences in soil hydraulic properties. The soils of the ponderosa pine forest contain clay

  20. Studies on application of annatto (Bixa orellena L.) dye formulations in dairy products

    OpenAIRE

    Sathiya Mala, Kripanand; Prabhakara Rao, Pamidighantam; Prabhavathy, Manda Babu; Satyanarayana, Akula

    2013-01-01

    Annatto is often used to add color to dairy products such as butter, cheese, or puddings. In India usage of annatto is restricted to butter and cheese, however there are no tailor made formulations available to obtain standardized colour shades for the products. Hence a study was initiated to develop the appropriate annatto dye formulations and level of application in few dairy products (butter, cheese, paneer, biscuit cream, icing cream). Dye extracted from annatto seeds was used for the pre...

  1. Molecular dynamics study of biodegradation of azo dyes via their interactions with AzrC azoreductase.

    Science.gov (United States)

    Haghshenas, Hamed; Kay, Maryam; Dehghanian, Fariba; Tavakol, Hossein

    2016-01-01

    Azo dyes are one of the most important class of dyes, which have been widely used in industries. Because of the environmental pollution of azo dyes, many studies have been performed to study their biodegradation using bacterial systems. In present work, the AzrC of mesophilic gram-positive Bacillus sp. B29 has been considered to study its interaction with five common azo dyes (orange G, acid red 88, Sudan I, orange I, and methyl red). The molecular dynamics simulations have been employed to study the interaction between AzrC and azo dyes. The trajectory was confirmed using root mean square deviation and the root mean square fluctuation analyses. Then, the hydrogen bond and alanine scanning analyses were performed to reveal active site residues. Phe105 (A), Phe125 (B), Phe172 (B), and Pro132 (B) have been found as the most important hydrophobic residues whereas Asn104 (A), Tyr127 (B), and Asn187 (A) have key role in making hydrogen bond. The results of molecular mechanics Poisson-Boltzmann surface area and molecular mechanics generalized Born surface area calculations proved that the hydrophobic azo dyes like Acid red 88 binds more tightly to the AzrC protein. The calculated data suggested MR A 121 (B) I as a potential candidate for improving the AzrC-MR interactions.

  2. Resting Study of Tracer Experiment on Catalytic Wet Oxidation Reactor under Micro-gravity and Earth Gravity Conditions

    Institute of Scientific and Technical Information of China (English)

    YANG Ji; JIA Jin-ping

    2005-01-01

    The International Space Station(ISS) employs catalytic wet oxidation carried out in a Volatile Reactor Assembly (VRA) for water recycling. Previous earth gravity experiments show that the VRA is very effective at removing polar,low molecular weight organics. To compare the reactor performance under micro-gravity and Earth gravity conditions,a tracer study was performed on a space shuttle in 1999 by using 0. 2% potassium carbonate as the chemical tracer.In this paper, the experimental data were analyzed and it is indicated that the reactor can be considered as a plug flow one under both micro-gravity and earth gravity experimental conditions. It has also been proved that dispersion is not important in the VRA reactor under the experimental conditions. Tracer retardation was observed in the experiments and it is most likely caused by catalyst adsorption. It is concluded that the following reasons may also have influence on the retardation of mean residence time: (1) the liquid can be held by appurtenances, which will retard the mean residence time; (2) the pores can hold the tracer, which can also retard the mean residence time.

  3. Comparative Study of the Impact of Two Types of Natural Dyes and Synthetic Dyes on the Fabric Comfort Level

    Institute of Scientific and Technical Information of China (English)

    Liu Yushi; Wang Yuqiu; Yun Song; Deng Ruoyu; Pan Yuan; Li Tianxue; Li Xiuzhi

    2015-01-01

    In order to research whether the Natural Dyes areremarkably different from the chemical dyes in practical application, four experiments relating to the fabric comfort degree were selected for operation and a social survey experiment was also conducted. The research was conducted from the two perspectives of scientific tests and subjective judgments. Through the scientific tests and social survey, it was concluded that the impact of Natural Dyes and that of Synthetic Dyes have little difference towards the fabric comfort degree, but there are still some findings need to be noticed through the conclusion.

  4. Theoretical study on the application of double-donor branched organic dyes in dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yan-Hong; Liu, Rui-Rui [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China); Zhu, Kai-Li [College of Chemistry and Life Science, Gansu Normal University for Nationalities, Hezuo, 747000, Gansu (China); Song, Yan-Lin [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China); Geng, Zhi-Yuan, E-mail: zhiyuangeng@126.com [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China)

    2016-09-15

    A novel organic dye with 2D-A structure has been designed and calculated whereby density functional theory (DFT) and time-dependent density functional theory (TD-DFT) for dye-sensitized solar cells. The double-donor branched dye which was consisted of two separated light-harvesting moieties was beneficial to photocurrent generation. First, we discussed the effects of different donor chains on photoelectric performance in the dye molecule, using the DTP-B8 which was a previously reported structure as the reference. Only to conclude that the suitable length can achieve the satisfactory efficiency. Secondly, to modify and sift potential sensitizers further, three series of dyes (BC-series, CB-series and CC-series) were designed and characterized. The increased molar extinction coefficient and the red-shifted λ{sub max} was attributed to an increasing in electron conjunction. This work presented a new route to design sensitizers that provide two channels for donating more electrons and improve the final efficiency. It is expected to provide some theoretical guidance on designing and synthetizing high efficiency photosensitive dye in the future experiments. - Highlights: • A novel organic dye with 2D-A structure was designed and characterized. • The double-donor branched dye was consisted of two separated light-harvesting paths. • The double-donor branched dye was beneficial to photocurrent generation. • The molar extinction coefficient was greatly improved in this novel structure. • Four promising candidates have been screened out.

  5. Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site characterization study; Progress report, April 1, 1993--June 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Dombrowski, T.; Stetzenbach, K.

    1993-08-01

    This report is in two parts one for the fluorinated benzoic acids and one for the fluorinated aliphatic acids. The assumptions made in the report regarding the amount of tracer that will be used, dilution of the tracer during the test and the length of exposure (if any) to individuals drinking the water were made by the authors. These assumptions must really come from the USGS hydrologists in charge of the c-well tracer testing program. Accurate estimates of dilution of the tracer during the test are also important because of solubility limitations of some of the tracers. Three of the difluorobenzoic acids have relatively low solubilities and may not be usable if the dilution estimates are large. The toxicologist that reviewed the document agreed with our conclusion that the fluorinated benzoic and toluic acids do not represent a health hazard if used under the conditions as outlined in the report. We are currently testing 15 of these compounds, and if even if three difluorobenzoic acids cannot be used because of solubility limitations we will still have 12 tracers. The toxicologist felt that the aliphatic fluorinated acids potentially present more of a health risk than the aromatic. This assessment was based on the fact of a known allergic response to halothane anesthetic. This risk, although minimal, is known and he felt that was enough reason to recommend against their use. The authors feel that the toxicologists interpretation of this risk was overly conservative, however, we will not go against his recommendation at this time for the following reasons. First, without the aliphatic compounds we still have 12 to 15 fluorinated aromatic acids which, should be enough for the c-well tests. Second, to get a permit to use aliphatic compounds would undoubtedly require a hearing which could be quite lengthy.

  6. Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain site characterization study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Stetzenbach, K.; Farnham, I.

    1996-06-01

    Extensive tracer testing is expected to take place at the C-well complex in the Nevada Test Site as part of the Yucca Mountain Site Characterization Project. The C-well complex consists of one pumping well, C3, and two injection wells, C1 and C2 into which tracer will be introduced. The goal of this research was to provide USGS with numerous tracers to completed these tests. Several classes of fluorinated organic acids have been evaluated. These include numerous isomers of fluorinated benzoic acids, cinnamic acids, and salicylic acids. Also several derivatives of 2-hydroxy nicotinic acid (pyridone) have been tested. The stability of these compounds was determined using batch and column tests. Ames testing (mutagenicity/carcinogenicity) was conducted on the fluorinated benzoic acids and a literature review of toxicity of the fluorobenzoates and three perfluoro aliphatic acids was prepared. Solubilities were measured and method development work was performed to optimize the detection of these compounds. A Quality Assurance (QA) Program was developed under existing DOE and USGS guidelines. The program includes QA procedures and technical standard operating procedures. A tracer test, using sodium iodide, was performed at the C-well complex. HRC chemists performed analyses on site, to provide real time data for the USGS hydrologists and in the laboratories at UNLV. Over 2,500 analyses were performed. This report provides the results of the laboratory experiments and literature reviews used to evaluate the potential tracers and reports on the results of the iodide C-well tracer test.

  7. Study on the Dyeing Performance of Natural Vegetable Dye of Huaimi%天然植物染料槐米的染色性能研究

    Institute of Scientific and Technical Information of China (English)

    余志成; 周秋宝; 陶尧定

    2001-01-01

    In this paper, it is studied the extracting conditions and the dyeing process of Huaimi, then compared the dyeing performance and the wet-fastness of it to silk with that to cotton fabrics.%对槐米染料的提取条件、染色工艺进行了试验,并对槐米在真丝绸和棉布上的染色性能、湿牢度进行了比较。

  8. A pilot study of the behavior of gas- and particle-phase ETS tracers in residences

    Energy Technology Data Exchange (ETDEWEB)

    Apte, Michael; Gundel, Lara; Dod, Raymond; Chang, Gee-Min; Sextro, Richard

    2002-02-01

    Our previous study of environmental tobacco smoke (ETS) in a three-room environmental chamber showed that smoking history significantly influenced inter-room ETS transport, particularly of gas-phase nicotine. We conducted a three-home pilot study where smoking was limited to one room. Single-smoker residences were monitored during five one-week periods while the smoker participated in a smoking cessation program. Nicotine traced ETS particles were detected reliably in the smoking rooms (SRs) and unreliably in the non-smoking rooms (NSRs). On average, the ventilation- and volume-normalized smoking rate, 0.1 Cigarette-h{sup -1} m{sup -3}, added about 17 and 4 {micro}g m{sup -3} of ETS particles into the SR and NSR, while average nicotine concentration increases were 2 and 0.06 {micro}g m{sup -3}, respectively. Thus, nicotine tracers may underestimate ETS particle exposure in a NSR (e.g., a child's bedroom) by a factor of 2 to 8. In other words, ETS exposure predicted from nicotine concentrations could be almost an order of magnitude lower than actual exposure.

  9. Sinks for nitrogen inputs in terrestrial ecosystems: a meta-analysis of 15N tracer field studies

    Science.gov (United States)

    Templer, P.H.; Mack, M.C.; Chapin, F. S.; Christenson, L.M.; Compton, J.E.; Crook, H.D.; Currie, W.S.; Curtis, C.J.; Dail, D.B.; D'Antonio, C. M.; Emmett, B.A.; Epstein, H.E.; Goodale, C.L.; Gundersen, P.; Hobbie, S.E.; Holland, K.; Hooper, D.U.; Hungate, B.A.; Lamontagne, S.; Nadelhoffer, K.J.; Osenberg, C.W.; Perakis, S.S.; Schleppi, P.; Schimel, J.; Schmidt, I.K.; Sommerkorn, M.; Spoelstra, J.; Tietema, A.; Wessel, W.W.; Zak, D.R.

    2012-01-01

    Effects of anthropogenic nitrogen (N) deposition and the ability of terrestrial ecosystems to store carbon (C) depend in part on the amount of N retained in the system and its partitioning among plant and soil pools. We conducted a meta-analysis of studies at 48 sites across four continents that used enriched 15N isotope tracers in order to synthesize information about total ecosystem N retention (i.e., total ecosystem 15N recovery in plant and soil pools) across natural systems and N partitioning among ecosystem pools. The greatest recoveries of ecosystem 15N tracer occurred in shrublands (mean, 89.5%) and wetlands (84.8%) followed by forests (74.9%) and grasslands (51.8%). In the short term (15N tracer application), total ecosystem 15N recovery was negatively correlated with fine-root and soil 15N natural abundance, and organic soil C and N concentration but was positively correlated with mean annual temperature and mineral soil C:N. In the longer term (3–18 months after 15N tracer application), total ecosystem 15N retention was negatively correlated with foliar natural-abundance 15N but was positively correlated with mineral soil C and N concentration and C: N, showing that plant and soil natural-abundance 15N and soil C:N are good indicators of total ecosystem N retention. Foliar N concentration was not significantly related to ecosystem 15N tracer recovery, suggesting that plant N status is not a good predictor of total ecosystem N retention. Because the largest ecosystem sinks for 15N tracer were below ground in forests, shrublands, and grasslands, we conclude that growth enhancement and potential for increased C storage in aboveground biomass from atmospheric N deposition is likely to be modest in these ecosystems. Total ecosystem 15N recovery decreased with N fertilization, with an apparent threshold fertilization rate of 46 kg N·ha-1·yr-1 above which most ecosystems showed net losses of applied 15N tracer in response to N fertilizer addition.

  10. An electro-optical and electron injection study of benzothiazole-based squaraine dyes as efficient dye-sensitized solar cell materials: a first principles study.

    Science.gov (United States)

    Al-Fahdan, Najat Saeed; Asiri, Abdullah M; Irfan, Ahmad; Basaif, Salem A; El-Shishtawy, Reda M

    2014-12-01

    Squaraine dyes have attracted significant attention in many areas of daily life from biomedical imaging to semiconducting materials. Moreover, these dyes are used as photoactive materials in the field of solar cells. In the present study, we investigated the structural, electronic, photophysical, and charge transport properties of six benzothiazole-based squaraine dyes (Cis-SQ1-Cis-SQ3 and Trans-SQ1-Trans-SQ3). The effect of electron donating (-OCH3) and electron withdrawing (-COOH) groups was investigated intensively. Ground state geometry and frequency calculations were performed by applying density functional theory (DFT) at B3LYP/6-31G** level of theory. Absorption spectra were computed in chloroform at the time-dependent DFT/B3LYP/6-31G** level of theory. The driving force of electron injection (ΔG (inject)), relative driving force of electron injection (ΔG r (inject)), electronic coupling constants (|VRP|) and light harvesting efficiency (LHE) of all six compounds were calculated and compared with previously studied sensitizers. The ΔG (inject), ΔG r (inject) and |VRP| of all six compounds revealed that these sensitizers would be efficient dye-sensitized solar cell materials. Cis/Trans-SQ3 exhibited superior LHE as compared to other derivatives. The Cis/Trans geometric effect was studied and discussed with regard to electro-optical and charge transport properties.

  11. Tracer-based quantification of individual frac discharge in single-well multiple-frac backflow: sensitivity study

    Science.gov (United States)

    Ghergut, Julia; Behrens, Horst; Sauter, Martin

    2014-05-01

    Within the deep-geothermal research project at GroßSchönebeck in the NE German Basin, targeting volcanic rocks (Lower Rotliegend) and siliciclastics (Upper Rotliegend) in the Lower Permian by means of a well doublet with several screening intervals between 3815 and 4247 m b.s.l., several artificial fractures with different geometric and hydraulic characteristics were created at each well, aiming to increase reservoir performance [1], [2]. It could not be told a priori which of the various fracturing treatments was to prove as most promising in terms of future reservoir productivity. At the intended-production well (GS-4), one large-area waterfrac was created in the low-permeability volcanic rocks, and two gel-proppant fractures in selected sandstone layers. Each fracturing treatment was accompanied by the injection of a water-dissolved tracer slug, followed by a defined volume of tracer-free ('chaser') fluid [3]. Each frac received a different species of a sulfonated aromatic acid salt, as a conservative water tracer. During subsequent backflow tests (either gas-based lifting, or production by means of a downhole submersible pump), each frac can contribute a certain (more or less constant) amount to the measured total discharge (also depending on whether and when each frac 'starts' contributing, and which effective aperture and area it actually 'manifests' during the process). Since these individual-frac discharge amounts cannot be measured directly, it was endeavoured to indirectly determine ('resolve') them from tracer signals as detectable in the overall backflow discharge. Therefore, we need to examine how these tracer signals depend on local discharge values and on local hydrogeologic parameters (matrix porosity, permeability distribution; frac transmissivity, thickness, effective area and aperture), and to what extent hydrogeological uncertainty will impede the inversion of local discharge values. To this end, a parameter sensitivity study was conducted on

  12. Kinetics and Adsorption Isotherms Studies of Acridine Orange Dye from Aqueous Solution by Activated Charcoal

    Directory of Open Access Journals (Sweden)

    *N. Qamar

    2014-12-01

    Full Text Available The goal of this research is to evaluate the efficiency of charcoal as low coast and effective adsorbent for acridine orange (a cationic dye from aqueous solution at room temperature. Effect of initial pH (2-8, shaking time (5min. - 1hour, adsorbent dose (0.1gm- 0.9gm and dye concentration (37mg/30ml-185mg/30ml were investigated. Results demonstrated that charcoal act as good adsorbent for the removal AO where 99.15% of the dye was adsorbed within 30 minutes. For the maximum dye removal efficiency (100%, optimum conditions were obtained at pH 8 (99.24%, adsorbent dose of 0.9g and dye concentration of 185 mg with charcoal. Kinetics of adsorption was investigated as well as Langmuir and Freundlich isotherms were employed to describe equilibrium studies. The Langmuir adsorption isotherms models and pseudo second order kinetics fitted the experimental data best with high regression coefficient R2. The results of the present studies points to the potential of charcoal as an effective adsorbent for the removal of dye from contaminated water sources.

  13. Lead isotope ratios as a tracer for lead contamination sources: A lake Andong case study

    Directory of Open Access Journals (Sweden)

    Kim Y. H

    2013-04-01

    Full Text Available The objective of this study was to evaluate stable Pb isotope signatures as a tracer for Pb contamination in Lake Andong. For Pb isotope analysis, we collected water and sediment from Lake Andong, particles in the air, soils, and stream water, mine tailings, sludge and wastewater from zinc smelting around lake Andong watershed. The results showed that Pb isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for zinc concentrate were 18.809 ± 0.322, 15.650 ± 0.062, and 38.728 ± 0.421, respectively. In wastewater, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb were 17.363 ± 0.133, 15.550 ± 0.025, and 37.217 ± 0.092, respectively. Additionally, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for sludge were 17.515 ± 0.155, 15.537 ± 0.018, and 37.357 ± 0.173, respectively. These values were similar to those in zinc and lead concentrate originated from Canada and South America. In contrast, Pb isotope ratios of soil, tailings and sediment from Lake Andong were similar to those of Korean ore. Atmospheric particles showed different patterns of Pb isotope ratios from sediments, soils, and zinc smelting and this needs further investigation in order to identify atmospheric Pb sources.

  14. Sediments as tracers for transport and deposition processes in peri-alpine lakes: A case study

    Science.gov (United States)

    Righetti, Maurizio; Toffolon, Marco; Lucarelli, Corrado; Serafini, Michele

    2011-12-01

    SummaryThe benthic sediment fingerprint is analysed in the small peri-alpine lake Levico (Trentino, Italy) to identify the causes of recurrent phenomena of turbidity peaks, particularly evident in a littoral region of the water body. In order to study the sediment transport processes, we exploit the fact that the sediment supply from the major tributary has a specific chemical composition, which differs from that of the nearby lake basin. Three elements (Fe, Al, K) have been used as tracers to identify the source and the deposition patterns of tributary sediments, and another typical element, Si, has been critically analysed because of its dual (allochthonous and autochthonous) origin. Several samples of the benthic material have been analysed using SEM-EDS, and the results of the sedimentological characterisation have been compared with the patterns of sediment accumulation at the bed of the lake obtained using a three-dimensional numerical model, in response to the tributary supply under different external forcing and stratification conditions. The coupled use of field measurements and numerical results suggests that the turbidity phenomena are strongly related to the deposition of the sediments supplied by the tributary stream, and shows that it is possible to reconstruct the process of local transport when the tributary inflow is chemically specific.

  15. Clinical studies of bone metabolism using a simple model of calcium tracer kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Roncari, G.

    1981-08-01

    Bone metabolism studies were performed in 44 subjects with and without bone disease using a calcium tracer kinetics model, the central feature of which is an expanding exchangeable calcium pool. In normal subjects the accretion rate and the exchangeable calcium pool ranged from 1.49 to 8.45 (mean 3.9 +- 2.05) mg.d/sup -1/kg/sup -1/ and from 60 to 131 (mean 81.25 +- 18.11) mg.kg/sup -1/, respectively. The patients with osteogenesis imperfecta, Pierre Marie's disease and one out of two cases of hypoparathyroidism had values which fell within the normal range. Both the accretion rate and the exchangeable calcium pool were significantly elevated in patients with Paget's disease and with hyperparathyroidism. Uremic patients with generalizated bone lesions had accretion rates or both parameters elevated. As far as patients with successful renal transplant are concerned, the results suggest that this method is a very poor means for detecting bone disorders with only focal lesions. In contrast, the method can be very useful when persistent renal osteodystrophy or secondary hyperparathyroidism are suspected.

  16. Fate of thymic lymphocytes. [/sup 125/IudR and /sup 3/HTdR tracer studies in mice

    Energy Technology Data Exchange (ETDEWEB)

    Laissue, J A; Chanana, A D; Cronkite, E P; Joel, D D

    1976-01-01

    Data are summarized from a number of studies on the fate of thymic lymphocytes. Results are reported from studies in mice in which /sup 125/IudR and /sup 3/HTdR were used as tracers to study the production, maturation, migration, and life span of thymic lymphocytes. It is pointed out that thymus-derived cells constitute the majority of recirculating lymphocytes and that peripheral, differentiated thymus-derived lymphocytes exhibit a number of immunological functions. 114 references.

  17. Dual signature tracer: A new tool for soil management and research.

    Science.gov (United States)

    Poleykett, Jack; Quinton, John; Armstrong, Alona; Maher, Barbara; Black, Kevin

    2015-04-01

    The significant detrimental effects that occur, both on and off site due to the transport of soil are well documented. Now more than ever, it is vital to understand the pathways, processes and fate of transported sediments, to underpin environmental strategy and develop robust forecast models. Researchers have employed a broad range of materials and techniques to trace the movement of soil through space and time. However, three primary challenges still remain: 1) to develop a tracer that has the same or similar hydraulic characteristics as soil: 2) to develop a tracer able to replicate the broad and variable particle size distribution of soils; and: 3) to develop a tracing methodology that increases the volume, and quality of data collected from the field. This study approaches these challenges using a unique 'dual signature' tracer comprising natural mineral material directly coated with a fluorescent dye pigment and loaded during coating with a naturally occurring magnetic mineral oxide creating a tracer with both fluorescent properties and para-magnetic character. An assessment of the effectiveness of the tracer as a tracer of soil was conducted at the soil box and plot scale under controlled rainfall conditions, to: 1) examine the behaviour of the tracer, and: 2) to assess the efficiency of the different tools available to monitor the tracer post- deployment. At the plot scale, a unique site specific tracer was developed to match the hydraulic characteristics (particle size distribution and specific gravity), of the native soil enabling the source-sink relationship, transport pathways and transport rate through the environment to be investigated. Spatial mapping of the tracer distribution within each plot was also conducted using photography and Ultra Violet (UV) illumination. The results of this study provide the basis for the development of a unique soil tracing methodology, which can be applied to investigate soil transport processes, at a range of scales in

  18. In Vitro Polarized Resonance Raman Study of N719 and N719-TBP in Dye Sensitized Solar Cells

    DEFF Research Database (Denmark)

    Hassing, Søren; Jernshøj, Kit Drescher; Nguyen, Phuong Tuyet;

    2016-01-01

    the adsorption of the dye on TiO2 can be obtained. Furthermore it is found that the polarization fluorescence anisotropy is very different for adsorbed and non-adsorbed dye molecules. This information is automatically obtained when processing the Raman data. The conclusion is that if the polarization properties......Abstract: The working efficiency of dye-sensitized solar cells (DSCs) depends on the long-term stability of the dye itself and on the microscopic structure of the dye-semiconductor interface. Previous experimental studies of DSCs based on ruthenium dye with bipyridine ligands (N719) adsorbed...... on N719/TiO2 – DSCs that by combining an analysis of the wave number dependent polarization of these modes with the small shifts observed in the visible absorption spectra of adsorbed, non-adsorbed molecules and degradation products new and more reliable information about dye stability and about...

  19. Decolorization of anthraquinonic dyes from textile effluent using horseradish peroxidase: optimization and kinetic study.

    Science.gov (United States)

    Šekuljica, Nataša Ž; Prlainović, Nevena Ž; Stefanović, Andrea B; Žuža, Milena G; Čičkarić, Dragana Z; Mijin, Dušan Ž; Knežević-Jugović, Zorica D

    2015-01-01

    Two anthraquinonic dyes, C.I. Acid Blue 225 and C.I. Acid Violet 109, were used as models to explore the feasibility of using the horseradish peroxidase enzyme (HRP) in the practical decolorization of anthraquinonic dyes in wastewater. The influence of process parameters such as enzyme concentration, hydrogen peroxide concentration, temperature, dye concentration, and pH was examined. The pH and temperature activity profiles were similar for decolorization of both dyes. Under the optimal conditions, 94.7% of C.I. Acid Violet 109 from aqueous solution was decolorized (treatment time 15 min, enzyme concentration 0.15 IU/mL, hydrogen peroxide concentration 0.4 mM, dye concentration 30 mg/L, pH 4, and temperature 24°C) and 89.36% of C.I. Acid Blue 225 (32 min, enzyme concentration 0.15 IU/mL, hydrogen peroxide concentration 0.04 mM, dye concentration 30 mg/L, pH 5, and temperature 24°C). The mechanism of both reactions has been proven to follow the two substrate ping-pong mechanism with substrate inhibition, revealing the formation of a nonproductive or dead-end complex between dye and HRP or between H2O2 and the oxidized form of the enzyme. Both chemical oxygen demand and total organic carbon values showed that there was a reduction in toxicity after the enzymatic treatment. This study verifies the viability of use of horseradish peroxidase for the wastewaters treatment of similar anthraquinonic dyes.

  20. Decolorization of Anthraquinonic Dyes from Textile Effluent Using Horseradish Peroxidase: Optimization and Kinetic Study

    Directory of Open Access Journals (Sweden)

    Nataša Ž. Šekuljica

    2015-01-01

    Full Text Available Two anthraquinonic dyes, C.I. Acid Blue 225 and C.I. Acid Violet 109, were used as models to explore the feasibility of using the horseradish peroxidase enzyme (HRP in the practical decolorization of anthraquinonic dyes in wastewater. The influence of process parameters such as enzyme concentration, hydrogen peroxide concentration, temperature, dye concentration, and pH was examined. The pH and temperature activity profiles were similar for decolorization of both dyes. Under the optimal conditions, 94.7% of C.I. Acid Violet 109 from aqueous solution was decolorized (treatment time 15 min, enzyme concentration 0.15 IU/mL, hydrogen peroxide concentration 0.4 mM, dye concentration 30 mg/L, pH 4, and temperature 24°C and 89.36% of C.I. Acid Blue 225 (32 min, enzyme concentration 0.15 IU/mL, hydrogen peroxide concentration 0.04 mM, dye concentration 30 mg/L, pH 5, and temperature 24°C. The mechanism of both reactions has been proven to follow the two substrate ping-pong mechanism with substrate inhibition, revealing the formation of a nonproductive or dead-end complex between dye and HRP or between H2O2 and the oxidized form of the enzyme. Both chemical oxygen demand and total organic carbon values showed that there was a reduction in toxicity after the enzymatic treatment. This study verifies the viability of use of horseradish peroxidase for the wastewaters treatment of similar anthraquinonic dyes.

  1. Study of bio-degradation and bio-decolourization of azo dye by Enterobacter sp. SXCR.

    Science.gov (United States)

    Prasad, Shiv Shankar; Aikat, Kaustav

    2014-01-01

    The objective of this study was to evaluate the decolourization potential of textile dyes by a relatively newly identified bacteria species, Enterobacter sp. SXCR which was isolated from the petroleum polluted soil samples. The bacterial strain was identified by 16S rRNA gene sequence analysis. The effects of operational conditions like initial dye concentration, pH, and temperature were optimized to develop an economically feasible decolourization process. The isolate was able to decolourize sulphonated azo dye (Congo red) over a wide range (0.1-1 gl(-1)), pH 5-9, and temperature 22-40 degrees C in static condition. Anaerobic condition with minimal salt medium supplemented with 2 gl(-1) glucose, pH 7 and 34 degrees C were considered to be the optimum decolourizing condition. The bacterial isolate SXCR showed a strong ability to decolourize dye (0.2 gl(-1)) within 93 h. The biodegradation was monitored by UV-vis, fourier transform infra-red spectroscopy (FTIR) spectroscopy and high performance liquid chromatography (HPLC). Furthermore, the involvement of azoreductase in the decolourization process was identified in this strain. Cells of Enterobacter cloacae were immobilized by entrapment in calcium-alginate beads. Immobilized bacterial cells were able to reduced azo bonds enzymatically and used as a biocatalyst for decolourization of azo dye Congo red. Michaelis-Menten kinetics was used to describe the correlation between the decolourization rate and the dye concentration.

  2. Study of the conditions affecting dye adsorption on titania films and of their effect on dye photodegradation rates.

    Science.gov (United States)

    Strataki, Nikoleta; Bekiari, Vlasoula; Lianos, Panagiotis

    2007-07-31

    Nanocrystalline titania films have been deposited on glass slides by the sol-gel technique in the presence of surfactant, which plays the role of template of the nanostructure. Several different dyes, both anionic and cationic, have been adsorbed on these films from aqueous solutions. Some of these dyes were adsorbed at large quantities some at lower quantities. Some of them were adsorbed in monomeric form and others formed aggregates. Aggregates are easily distinguished by absorption spectrophotometry, since absorption of light is observed at a different wavelength than monomer absorption in a dilute solution. In all cases, aggregation demonstrated a hypsochromic shift, indicating repulsive interactions, which are justified in view of the fact that titania surface is charged and that adsorbed molecules are aligned in parallel. The above titania films are hydroxylated. Therefore, cationic dyes were readily adsorbed. Anionic dyes could be adsorbed only from aqueous solutions brought at low pH. Photodegradation rates of adsorbed dyes were generally fast since these films are efficient photocatalysts. Nevertheless, photodegradation of an adsorbed dye was faster when the quantity of the dye was smaller. When the adsorbed dyes formed aggregates, aggregation had adverse effect on photodegradation rates.

  3. Teacher Education Graduate Tracer Study from 2010 to 2014 in One State University in Batangas, Philippines

    Directory of Open Access Journals (Sweden)

    Anania B. Aquino

    2015-12-01

    Full Text Available Teacher Education institutions primarily aim of producing competent and highly qualified graduates employable here and abroad. Tracer studies on graduates can appropriately provide valuable information for evaluating the results of the education and training of a specific institution of higher education. It collects essential information concerning the employment profile of graduates, their undergraduate experience, the first and current jobs of graduates and the relevance of their educational background and skills required in their job. The main objective of this study was to trace the employment profile of the graduates after they obtained their teacher education degree. The descriptive survey method of research was applied to this research with a survey questionnaire as the main data gathering instrument. It analyzed data from 129 respondents characterized by a preponderance of females over male as females and unmarried or single graduates as opposed to those who were married. The study found that there were more respondents who finished Bachelor of Secondary Education (BSED over Bachelor of Elementary Education. They obtained this degree as they believed that teaching is a rewarding and challenging profession, Majority are Licensure Examination for Teachers (LET passers and are employed in public schools at the time of the study. Their present job, mostly professional in nature, was also their first job and relevant to their degree. It took only a moderate period of time for most graduates to land a job. Most stay in their job for economic reason, finding communication skills and human relation skills as part of their teacher education preparation very relevant to their jobs.

  4. Inductively coupled plasma mass spectrometry for stable isotope metabolic tracer studies of living systems

    Energy Technology Data Exchange (ETDEWEB)

    Luong, Elise [Iowa State Univ., Ames, IA (United States)

    1999-05-10

    This dissertation focuses on the development of methods for stable isotope metabolic tracer studies in living systems using inductively coupled plasma single and dual quadrupole mass spectrometers. Sub-nanogram per gram levels of molybdenum (Mo) from human blood plasma are isolated by the use of anion exchange alumina microcolumns. Million-fold more concentrated spectral and matrix interferences such as sodium, chloride, sulfate, phosphate, etc. in the blood constituents are removed from the analyte. The recovery of Mo from the alumina column is 82 ± 5% (n = 5). Isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) is utilized for the quantitative ultra-trace concentration determination of Mo in bovine and human blood samples. The average Mo concentration in reference bovine serum determined by this method is 10.2 ± 0.4 ng/g, while the certified value is 11.5 ± 1.1 ng/g (95% confidence interval). The Mo concentration of one pool of human blood plasma from two healthy male donors is 0.5 ± 0.1 ng/g. The inductively coupled plasma twin quadrupole mass spectrometer (ICP-TQMS) is used to measure the carbon isotope ratio from non-volatile organic compounds and bio-organic molecules to assess the ability as an alternative analytical method to gas chromatography combustion isotope ratio mass spectrometry (GC-combustion-IRMS). Trytophan, myoglobin, and β-cyclodextrin are chosen for the study, initial observation of spectral interference of 13C+ with 12C 1H+ comes from the incomplete dissociation of myoglobin and/or β-cyclodextrin.

  5. Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO sub 2 catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Krishna, K.R.

    1992-01-01

    Fischer-Tropsch synthesis is a process in which CO and H{sub 2} react to give predominantly liquid hydrocarbons. The reaction can be considered a special type of polymerization in which the monomer is produced in situ, and chain growth occurs by a sequence of independently repeated additions of the monomer to the growing chain. A investigation has been conducted to study the CO hydrogenation reaction in order to better understand catalyst deactivation and the elementary surface processes involved in chain growth. Isotopic tracers are used in conjunction with transient-response techniques in this study of Fischer-Tropsch synthesis over Ru/TiO{sub 2} catalysts. Experiments are conducted at a total pressure of 1 atmosphere, reaction temperatures of 453--498 K and D{sub 2}/CO (or H{sub 2}/CO) ratios of 2--5. Synthesis products are analyzed by gas chromatography or isotope-ratio gas chromatography-mass spectrometry. Rate constants for chain initiation, propagation and termination are evaluated under steady-state reaction conditions by using transients in isotopic composition. The activation energy for chain termination is much higher than that for propagation, accounting for the observed decrease in the chain growth parameter are also estimated. Coverages by reaction intermediates are also estimated. When small amounts of {sup 12}C-labelled ethylene are added to {sup 13}CO/H{sub 2} synthesis gas, ethylene acts as the sole chain initiator. Ethylene-derived carbon also accounts for 45% of the C{sub 1} monomer pool. 102 refs., 29 figs., 11 tabs.

  6. Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO{sub 2} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Krishna, K.R.

    1992-01-01

    Fischer-Tropsch synthesis is a process in which CO and H{sub 2} react to give predominantly liquid hydrocarbons. The reaction can be considered a special type of polymerization in which the monomer is produced in situ, and chain growth occurs by a sequence of independently repeated additions of the monomer to the growing chain. A investigation has been conducted to study the CO hydrogenation reaction in order to better understand catalyst deactivation and the elementary surface processes involved in chain growth. Isotopic tracers are used in conjunction with transient-response techniques in this study of Fischer-Tropsch synthesis over Ru/TiO{sub 2} catalysts. Experiments are conducted at a total pressure of 1 atmosphere, reaction temperatures of 453--498 K and D{sub 2}/CO (or H{sub 2}/CO) ratios of 2--5. Synthesis products are analyzed by gas chromatography or isotope-ratio gas chromatography-mass spectrometry. Rate constants for chain initiation, propagation and termination are evaluated under steady-state reaction conditions by using transients in isotopic composition. The activation energy for chain termination is much higher than that for propagation, accounting for the observed decrease in the chain growth parameter are also estimated. Coverages by reaction intermediates are also estimated. When small amounts of {sup 12}C-labelled ethylene are added to {sup 13}CO/H{sub 2} synthesis gas, ethylene acts as the sole chain initiator. Ethylene-derived carbon also accounts for 45% of the C{sub 1} monomer pool. 102 refs., 29 figs., 11 tabs.

  7. An unsteady state tracer method for characterizing fractures in bedrock wells.

    Science.gov (United States)

    Libby, Jill L; Robbins, Gary A

    2014-01-01

    Evaluating contaminants impacting wells in fractured crystalline rock requires knowledge of the individual fractures contributing water. This typically involves using a sequence of tools including downhole geophysics, flow meters, and straddle packers. In conjunction with each other these methods are expensive, time consuming, and can be logistically difficult to implement. This study demonstrates an unsteady state tracer method as a cost-effective alternative for gathering fracture information in wells. The method entails introducing tracer dye throughout the well, inducing fracture flow into the well by conducting a slug test and then profiling the tracer concentration in the well to locate water contributing fractures where the dye has been diluted. By monitoring the development of the dilution zones within the wellbore with time, the transmissivity and the hydraulic head of the water contributing fractures can be determined. Ambient flow conditions and the contaminant concentration within the fractures can also be determined from the tracer dilution. This method was tested on a large physical model well and a bedrock well. The model well was used to test the theory underlying the method and to refine method logistics. The approach located the fracture and generated transmissivity values that were in excellent agreement with those calculated by slug testing. For the bedrock well tested, two major active fractures were located. Fracture location and ambient well conditions matched results from conventional methods. Estimates of transmissivity values by the tracer method were within an order of magnitude of those calculated using heat-pulse flow meter data.

  8. Comparison of [11C]cocaine binding at tracer and pharmacological doses of baboon brain: A PET study

    Energy Technology Data Exchange (ETDEWEB)

    Volkow, N.D.; Fowler, J.S.; Logan, J. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1994-05-01

    In vitro studies have shown that cocaine (C) binds to both high and low affinity sites on the dopamine transporter (DAT). We have previously characterized the binding of tracer doses of [{sup 11}C]cocaine (C*)to a high affinity site on the DAT. To assess if in vivo C also binds to low affinity sites we used PET to compare binding of tracer doses (17.8{plus_minus}12.2 {mu}g C) of C* to pharmacological doses (8 mg of C coadministered with C*). Sixteen paired studies were done to assess test/retest variability, specific versus non specific binding and to characterize binding profile. Dynamic scans were started immediately after injection of C* (5-8 mCi) for 50 min on the CTI-931 (6 x 6 x 6.5 mm FWHM). Time activity curves for tissue concentration and for unchanged tracer in plasma were used to calculate the transport constant between plasma and tissue (K1) and to obtain the distribution volume (DV). The ratio of the DV in striatum (ST) to that in cerebellum (CB) (which corresponds to Bmax/Kd-1) was used as model parameter. Peak brain uptake of C* was significantly higher for tracer than for pharmacological doses (0.041 versus 0.033 % dose/cc), as were the values for K1 (1.07{plus_minus}0.21 versus 0.68{plus_minus}0.26 (t=3.0 p<0.01)). Repeated measures were reproducible for tracer ({plus_minus}2%) and pharmacological doses of C* ({plus_minus}4%). Tracer dose C* showed highest binding and slowest clearance in ST which was reduced by C (0.5-2.0 mg/kg iv, -25 to -30%) and by drugs that inhibit DAT (2mg/kg nomifensine - 21%, 0.5 mg/kg methylphenidate -12%) and was increased by serotonin transporter inhibitors (5HT-Ti) (2 mg/kg citalopram +11%, 0.5 mg/kg fluoxetine +6%) and not changed by NE transporter inhibitors (0.5 mg/kg desipramine or 2 mg/kg tomoxetine). The increase with (5HT-Ti) may reflect neurotransmitter interactions or changes in bioavailability. At pharmacological doses C* showed homogeneous distribution and was not changed by C nor by any of the above drugs.

  9. Biosorption studies on waste cotton seed for cationic dyes sequestration: equilibrium and thermodynamics

    Science.gov (United States)

    Sivarajasekar, N.; Baskar, R.; Ragu, T.; Sarika, K.; Preethi, N.; Radhika, T.

    2017-07-01

    The immature Gossypium hirsutum seeds—an agricultural waste was converted into a novel adsorbent and its effectiveness for cationic dyes removal was discussed in this study. Characterization revealed that sulfuric acid activated waste Gossypium hirsutum seed (WGSAB) contains surface area 496 m2 g-1. The ability of WGSAB to adsorb basic red 2 (BR2) and basic violet 3 (BV3) from aqueous solutions has been studied. Batch adsorption studies were carried out at different initial dye concentrations (100-300 mg l-1), contact time (1-5 h), pH (2-12) and temperature (293-323 K) to understand the adsorption mechanism. Adsorption data were modeled using Langmuir, Freundlich and Toth adsorption isotherms. Equilibrium data of the adsorption process fitted very well to the Toth model for both dyes. The Langmuir maximum adsorption capacity was 66.69 mg g-1 for BV3 and 50.11 mg g-1 for BR2 at optimum conditions. The near unity value of Toth isotherm constant (BR2: 0.999 and BV3: 1.0) indicates that WGSAB surface is heterogeneous in nature. The maximum adsorption capacity predicted by Toth isotherm of BV3 (66.699 mg g-1) is higher than BR2 (50.310 mg g-1). The kinetic investigation revealed that the BR2 and BV3 were chemisorbed on WGSAB surface following Avrami fractional order kinetics. Further, the fractional order and rate constant values are almost similar for every concentration in both the dyes. The thermodynamic parameters such as Δ H 0, Δ S 0 and Δ G 0 were evaluated. The dye adsorption process was found to be spontaneous and endothermic for the two dyes. Regeneration of WGSAB exhausted by the two dyes could be possible via acetic acid as elutant.

  10. Transport study in unsaturated porous media by tracer experiment in a dichromatic X-ray experimental device

    Directory of Open Access Journals (Sweden)

    Néel M.C.

    2013-05-01

    Full Text Available Estimating contaminant migration in the context of waste disposal and/or environmental remediation of polluted soils requires a complete understanding of the underlying transport processes. In unsaturated porous media, water content is one of the most determining parameters to describe solute migration because it impacts directly on solute pore velocity. However, numerous studies are satisfied with only a global or a partial spatial distribution of water content within the studied porous media. Therefore, distribution of water content in porous media must be precisely achieved to optimize transport processes modeling. Tracer experiments with downward flow were performed on the BEETI experimental device equipped with a sand column. Water content and concentration profiles of tracer (KI were measured along the column during experiment. The relative dispersion of water content, calculated along the column, gives an idea of influence of this parameter on transport properties. A relationship between pore velocity, Darcy flow velocity and water content is proposed.

  11. Transport study in unsaturated porous media by tracer experiment in a dichromatic X-ray experimental device

    Science.gov (United States)

    Latrille, C.; Néel, M. C.

    2013-05-01

    Estimating contaminant migration in the context of waste disposal and/or environmental remediation of polluted soils requires a complete understanding of the underlying transport processes. In unsaturated porous media, water content is one of the most determining parameters to describe solute migration because it impacts directly on solute pore velocity. However, numerous studies are satisfied with only a global or a partial spatial distribution of water content within the studied porous media. Therefore, distribution of water content in porous media must be precisely achieved to optimize transport processes modeling. Tracer experiments with downward flow were performed on the BEETI experimental device equipped with a sand column. Water content and concentration profiles of tracer (KI) were measured along the column during experiment. The relative dispersion of water content, calculated along the column, gives an idea of influence of this parameter on transport properties. A relationship between pore velocity, Darcy flow velocity and water content is proposed.

  12. A Study on the Efficiency Improvement of Dye-Sensitized Solar Cell (DSSC) by Repeated Dye Coating.

    Science.gov (United States)

    Seo, Young Ho; Choi, Eun Chang; Hong, Byungyou

    2015-10-01

    Dye-sensitized solar cell (DSSC) is being extensively investigated as the next generation energy source. Despite of the attractive features like simple fabrication process and its economic efficiency, there are some problems such as low efficiency, long fabrication time and low long-term stability. Conventionally, the dye adsorption on TiO2 photo-electrode film needs long time in the solvent with low concentration of dye to get the high efficiency. In this work, the dye coating process was considerably shortened, albeit plenty of dye was used comparing with the conventional way. Our needs were met for the best result in our working environment and the relevant conditions to our work were obtained, which were the coating temperature of 70 °C, the dye concentration of 10 mM and the coating time of 3 min. And this coating process was successively repeated several times to maximize the dye adsorption and to improve the cell efficiency. Therefore, the efficiency increased by 13% in the proper condition.

  13. Tracer Study of Dentistry Graduates of one Higher Education Institution in the Philippines from 2008 to 2012

    OpenAIRE

    Jennifer D. Maderazo

    2016-01-01

    This tracer study determines the employment status of the graduates of Doctor of Dental Medicine of Lyceum of the Philippines University (LPU) from 2008-2012. It assessed the relevance of the Dentistry curriculum, knowledge, skills and attitude acquired by the graduates deemed to be relevant for their employment; identify the personal and professional characteristics and job placement of Dentistry graduates and the school related factors associated with their employment. This trac...

  14. Dye concentration study in PVK based light emitting diodes

    Science.gov (United States)

    Gautier-Thianche, E.; Sentein, C.; Nunzi, J.-M.; Lorin, A.; Denis, C.; Raimond, P.

    1998-06-01

    Light emitting diodes made of a single spin-coated layer of poly(9-vinylcarbazole) doped with coumarin-515 dye have been prepared. The influence of dye concentration on emission and electrical characteristics is evidenced. Two different regimes are identified. At low concentrations, hole injection barrier raises, holes are trapped and mobility decreases. External quantum efficiency increases with concentration. At concentrations larger than 10 per electron. Coumarin in a single-layer diode improves electron-hole injection and recombination balance more than an additional hole-blocking layer. Nous avons étudié des DEL constituées d'une monocouche de poly(9-vinylcarbazole) (PVK) dopée avec un colorant laser : la coumarine 515. Le taux de dopage en colorant influe sur les caractéristiques courant - tension et sur le rendement quantique d'électroluminescence. Aux faibles taux de dopage, la hauteur de la barrière d'injection des trous augmente, les trous sont piégés dans la matrice et leur mobilité décroît. Le rendement quantique externe augmente avec la concentration de dopant. Aux concentrations supérieures à 10 photoluminescence chute mais le rendement quantique externe augmente jusqu'à 0.1 recombinaison électron-trou bien mieux qu'une couche supplémentaire bloquant l'injection des trous.

  15. Sinks for nitrogen inputs in terrestrial ecosystems: a meta-analysis of 15N tracer field studies.

    Science.gov (United States)

    Templer, P H; Mack, M C; Chapin, F S; Christenson, L M; Compton, J E; Crook, H D; Currie, W S; Curtis, C J; Dail, D B; D'Antonio, C M; Emmett, B A; Epstein, H E; Goodale, C L; Gundersen, P; Hobbie, S E; Holland, K; Hooper, D U; Hungate, B A; Lamontagne, S; Nadelhoffer, K J; Osenberg, C W; Perakis, S S; Schleppi, P; Schimel, J; Schmidt, I K; Sommerkorn, M; Spoelstra, J; Tietema, A; Wessel, W W; Zak, D R

    2012-08-01

    Effects of anthropogenic nitrogen (N) deposition and the ability of terrestrial ecosystems to store carbon (C) depend in part on the amount of N retained in the system and its partitioning among plant and soil pools. We conducted a meta-analysis of studies at 48 sites across four continents that used enriched 15N isotope tracers in order to synthesize information about total ecosystem N retention (i.e., total ecosystem 15N recovery in plant and soil pools) across natural systems and N partitioning among ecosystem pools. The greatest recoveries of ecosystem 15N tracer occurred in shrublands (mean, 89.5%) and wetlands (84.8%) followed by forests (74.9%) and grasslands (51.8%). In the short term (ecosystem 15N recovery was negatively correlated with fine-root and soil 15N natural abundance, and organic soil C and N concentration but was positively correlated with mean annual temperature and mineral soil C:N. In the longer term (3-18 months after 15N tracer application), total ecosystem 15N retention was negatively correlated with foliar natural-abundance 15N but was positively correlated with mineral soil C and N concentration and C:N, showing that plant and soil natural-abundance 15N and soil C:N are good indicators of total ecosystem N retention. Foliar N concentration was not significantly related to ecosystem 15N tracer recovery, suggesting that plant N status is not a good predictor of total ecosystem N retention. Because the largest ecosystem sinks for 15N tracer were below ground in forests, shrublands, and grasslands, we conclude that growth enhancement and potential for increased C storage in aboveground biomass from atmospheric N deposition is likely to be modest in these ecosystems. Total ecosystem 15N recovery decreased with N fertilization, with an apparent threshold fertilization rate of 46 kg N x ha(-1) x yr(-1) above which most ecosystems showed net losses of applied 15N tracer in response to N fertilizer addition.

  16. Radon as a natural geochemical tracer for study of groundwater discharge into lakes

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Axel

    2008-06-27

    In the presented work the suitability of the naturally occurring radioactive noble gas isotope radon-222 for qualitative and quantitative description of groundwater discharge into lakes was studied. Basis of these investigations was the development of two innovative techniques for the on-site determination of radon in water. In the ex-situ radon measurement procedure, water from the source concerned is taken up in an exchange cell used for this purpose. Inside this cell, the radon dissolved in water is transferred via diffusion into a closed counter-flow of air and subsequently detected by a radon-in-air monitor. Where the in-situ radon determination is concerned, a module composed of a semipermeable membrane is introduced into a water column. Subsequently, the radon dissolved in the water body diffuses through the membrane into the corresponding air flow, by means of which it is transferred into a radon-in-air monitor and is detected. Combination of the developed mobile radon extraction techniques with a suitable and portable radon monitor allow the detection of radon-222 with sufficient accuracy (smaller 20 %) in groundwater as well as in surface waters, i.e., within a broad range of concentrations. Radon-222 was subsequently used to characterize groundwater discharge into a meromictic and a dimictic lake, i.e. two types of lake basically distinct from each other with respect to their water circulation properties were investigated. The use of the noble gas isotope radon-222 as a geochemical tracer makes the application of on-site detection techniques possible and that this in turn permits a rapid, reliable, and cost-effective assessment of groundwater discharge rates into lake water bodies.

  17. WLS助剂改性的棉纱线硫化染料浸染染色工艺研究%Study on dip dyeing of WLS agent modified cotton fabric with sulfur dye

    Institute of Scientific and Technical Information of China (English)

    刘元军; 王雪燕; 韩超; 刘元臣

    2014-01-01

    Cotton fabric was modified with cationic agent WLS, the influence of dyeing properties using dip dyeing process with sulfur dye was studied. And the optimal dyeing process of agent WLS modified cotton fabric with sulfur dye was optimized. Then the dyeing properties of the dip dyeing modified cotton fabric with sulfur dye were estimated. The result indicated that the dip dyeing modified cotton fabric with sulfur dye exhibited higher K/S value and higher dyeing percentage. Comparing to traditional crafts, dyeing WLS agent modified cotton solve problems of using sodium bisulfite, low dyeing percentage, wastewater pollution and so on. So the dip dyeing modified cotton fabric with sulfur dye is helpful to energy conservation and development of environmentally friendly dyeing process.%固定阳离子改性剂WLS改性棉纱线工艺,研究硫化染料浸染染色工艺条件对染色性能的影响,优选出改性棉纱线硫化染料浸染染色的最佳工艺,评价了改性棉纱线硫化染料浸染染色效果。结果表明:改性棉纱线硫化染料的上染百分率和K/S值显著提高。WLS助剂改性棉纱线解决了传统硫化染料染色时,还原剂用量大,染料上染率低,染色废水污染严重等问题,这种改性工艺对于节能减排,开发环保型染色工艺非常有利。

  18. An inexpensive field fluorometer for hydrogeological tracer tests with three tracers and turbidity measurement

    OpenAIRE

    Schnegg, Pierre-André

    2005-01-01

    The Geomagnetism Group of the University of Neuchâtel has recently designed a flow-through field fluorometer with added spectral capabilities for hydrological tracer tests. This instrument is equipped with four optical axes allowing water sample illumination with four independent light sources at different wavelenghs covering the full spectrum from UV to red. As many as three conveniently selected (dye) tracers can be simultaneously measured and separeted from a cocktail. Careful turbidity me...

  19. Photo-physical and structural studies of some synthesized arylazoquinoline dyes

    Science.gov (United States)

    Ghanadzadeh Gilani, A.; Taghvaei, V.; Moradi Rufchahi, E.; Mirzaei, M.

    2017-10-01

    This study presents the spectral and structure characteristics of seven azoquinoline dyes with different substituents and their new methylated counterparts for the first time, where some compounds are newly synthesized. The solvatochromic, tautomeric, halochromic, and dichroic behavior of the compounds were studied by electronic spectroscopy in various media. The different types of media were ordinary, multifunctional, and ordered liquids. The experiments were extended to include under acidic or basic conditions. The orientational behavior of the azo dye-doped liquid crystals was studied, and it was established that the azo form is the main species in high polar anisotropic media. The multi-parameter polarity scales were used to correlate the spectral data. Influence of acid and base on the absorption spectra of the dyes was also examined. Ionization constants for these dyes were determined in ethanol-water media. As a result, at the high dye concentrations, the intermolecular hydrogen bonding is more stable than the intra-molecular hydrogen bond, and therefore, the azo form is the main species in concentrated solutions. In order to provide more details, time-dependent density functional theory (TD-DFT) calculations were carried out for the representative models.

  20. Density Functional Theory Study on the Electronic Structures of Oxadiazole Based Dyes as Photosensitizer for Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Umer Mehmood

    2015-01-01

    Full Text Available The molecular structures and UV-visible absorption spectra of complex photosensitizers comprising oxadiazole isomers as the π-bridges were analyzed by density functional theory (DFT and time-dependent DFT. The ground state and excited state oxidation potentials, HOMOs and LUMOs energy levels, and electron injection from the dyes to semiconductor TiO2 have been computed in vacuum here. The results show that all of the dyes may potentially be good photosensitizers in DSSC. To justify the simulation basis, N3 dye was also simulated under the similar conditions. Simulated absorption spectrum, HOMO, LUMO, and band gap values of N3 were compared with the experimental values. We also computed the electronic structure properties and absorption spectra of dye/(TiO28 systems to elucidate the electron injection efficiency at the interface. This work is expected to give proper orientation for experimental synthesis.

  1. A spectroscopic study of dyes decomposition by irradiated nanocrystalline TiO2

    Science.gov (United States)

    Rosu, M. C.; Suciu, R. C.; Kasco, I.; Dreve, S. V.; Indrea, E.; Silipas, T. D.

    2009-08-01

    The photocatalytic activity of the TiO2 films prepared by wet-chemical techniques and deposited on the ITO glass was tested by examining the decomposition of violet gentian (VG), methylen blue (MB) and methyl green (MG) aqueous solutions under UV light illumination. The photodegradation processes of dyes have been studied using UV-VIS spectrophotometry and spectrofluorimetry. The comparative results of the present study demonstrate the capability of UV irradiation of the TiO2/ITO photocatalytic system to degrade studied organic dyes from aqueous solutions.

  2. Study of the influential factors in the simultaneous photocatalytic degradation process of three textile dyes.

    Science.gov (United States)

    Fernández, Cristina; Larrechi, M Soledad; Callao, M Pilar

    2009-10-15

    The influence of several factors in the simultaneous photocatalytic degradation of three textile dyes - Acid Red 97, Acid Orange 61 and Acid Brown 425 - has been studied using a fractional factorial design 2(5-1). The considered factors were: the initial concentration of each dye, the catalyst concentration (TiO(2)) and pH. First, we developed a rapid analytical methodology based on recording UV-visible spectra during the degradation process and a data treatment using multivariate curve resolution with alternating least squares (MCR-ALS), which enabled the three dyes to be quantified simultaneously despite the overlap of their spectra. The kinetic constant of degradation for each dye in all the experiments was evaluated. In all cases the degradation followed a first order kinetics. For a significance level of 5%, the most important factor in the photodegradation of each dye is the concentration of Acid Red 97, the degradation is more effective at higher pHs and, in the studied range, the concentration of the catalyst is not important.

  3. The Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome (TRA*CER) trial: study design and rationale.

    Science.gov (United States)

    2009-09-01

    The protease-activated receptor 1 (PAR-1), the main platelet receptor for thrombin, represents a novel target for treatment of arterial thrombosis, and SCH 530348 is an orally active, selective, competitive PAR-1 antagonist. We designed TRA*CER to evaluate the efficacy and safety of SCH 530348 compared with placebo in addition to standard of care in patients with non-ST-segment elevation (NSTE) acute coronary syndromes (ACS) and high-risk features. TRA*CER is a prospective, randomized, double-blind, multicenter, phase III trial with an original estimated sample size of 10,000 subjects. Our primary objective is to demonstrate that SCH 530348 in addition to standard of care will reduce the incidence of the composite of cardiovascular death, myocardial infarction (MI), stroke, recurrent ischemia with rehospitalization, and urgent coronary revascularization compared with standard of care alone. Our key secondary objective is to determine whether SCH 530348 will reduce the composite of cardiovascular death, MI, or stroke compared with standard of care alone. Secondary objectives related to safety are the composite of moderate and severe GUSTO bleeding and clinically significant TIMI bleeding. The trial will continue until a predetermined minimum number of centrally adjudicated primary and key secondary end point events have occurred and all subjects have participated in the study for at least 1 year. The TRA*CER trial is part of the large phase III SCH 530348 development program that includes a concomitant evaluation in secondary prevention. TRA*CER will define efficacy and safety of the novel platelet PAR-1 inhibitor SCH 530348 in the treatment of high-risk patients with NSTE ACS in the setting of current treatment strategies.

  4. Study of solid and liquid behavior in large copper flotation cells (130 m2 using radioactive tracers

    Directory of Open Access Journals (Sweden)

    Yianatos J.

    2013-05-01

    Full Text Available The behavior of the solid and liquid phases, in large flotation cells, was characterized by means of the radioactive tracer technique. The use of radioactive tracers enabled the identification of the Residence Time Distribution, of floatable and non-floatable solid, from continuous (on-line measuring at the output streams of the flotation cells. For this study, the proper radioactive tracers were selected and applied in order to characterize the different phases; i.e. for liquid phase Br-82 as Ammonium Bromide, for floatable solid recovered in the concentrate Cu-64, and for non-floatable solid in three particle size classes (coarse: >150 μm, intermediate: 45 μm, and fine: <45 μm, Na-24. The experimental results confirmed the strong effect of particle size on the Residence Time Distribution, and mean residence time of solids in larger flotation cells, and consequently in flotation hydrodynamics. From a hydrodynamic point of view, the experimental data confirmed that a single mechanical flotation cells, of large size, can deviate significantly from perfect mixing. The experimental work was developed in a 130 m3 industrial flotation cell of the rougher circuit at El Teniente Division, Codelco-Chile.

  5. Study of solid and liquid behavior in large copper flotation cells (130 m2) using radioactive tracers

    Science.gov (United States)

    Díaz, F.; Jiménez, O.; Yianatos, J.; Contreras, F.

    2013-05-01

    The behavior of the solid and liquid phases, in large flotation cells, was characterized by means of the radioactive tracer technique. The use of radioactive tracers enabled the identification of the Residence Time Distribution, of floatable and non-floatable solid, from continuous (on-line) measuring at the output streams of the flotation cells. For this study, the proper radioactive tracers were selected and applied in order to characterize the different phases; i.e. for liquid phase Br-82 as Ammonium Bromide, for floatable solid recovered in the concentrate Cu-64, and for non-floatable solid in three particle size classes (coarse: >150 μm, intermediate: 45 μm, and fine: flotation cells, and consequently in flotation hydrodynamics. From a hydrodynamic point of view, the experimental data confirmed that a single mechanical flotation cells, of large size, can deviate significantly from perfect mixing. The experimental work was developed in a 130 m3 industrial flotation cell of the rougher circuit at El Teniente Division, Codelco-Chile.

  6. Dyeing and Adsorption Studies of Madder (Rubia tinctorum on Wool Fibers

    Directory of Open Access Journals (Sweden)

    Mahmoud FEIZ

    2015-03-01

    Full Text Available In this study, the dyeing behavior of wool fabrics with madder has been studied. Three well-known types of adsorption isotherms i.e. the Nernst, Freundlich and Langmuir isotherms were used to fit the data. It was found that the adsorption isotherm of madder on wool fibers follows Freundlich type of adsorption. The exponent α in Freundlich isotherm equation (Cf = k.Csα was obtained 0.61 corresponding to 0.5 for the direct dyes on cellulosic fibers. The effect of salt and pH on dyeing of wool samples was investigated by the use of color characteristics measurements. The results showed that addition of salt and acid (pH 4.5 to the dyebath resulted in an increase of adsorption. DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5150

  7. Dyeing and Adsorption Studies of Madder (Rubia tinctorum on Wool Fibers

    Directory of Open Access Journals (Sweden)

    Mahmoud FEIZ

    2015-03-01

    Full Text Available In this study, the dyeing behavior of wool fabrics with madder has been studied. Three well-known types of adsorption isotherms i.e. the Nernst, Freundlich and Langmuir isotherms were used to fit the data. It was found that the adsorption isotherm of madder on wool fibers follows Freundlich type of adsorption. The exponent α in Freundlich isotherm equation (Cf = k.Csα was obtained 0.61 corresponding to 0.5 for the direct dyes on cellulosic fibers. The effect of salt and pH on dyeing of wool samples was investigated by the use of color characteristics measurements. The results showed that addition of salt and acid (pH 4.5 to the dyebath resulted in an increase of adsorption. DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5150

  8. Photophysical studies of some dyes in aqueous solution of triton X-100.

    Science.gov (United States)

    Bhowmik, Benoy B; Ganguly, Papia

    2005-12-01

    The spectral (both absorption and fluorescence) and photoelectrochemical studies of a few selective dyes, namely, anionic erythrosin B, neutral riboflavin and cationic safranin O have been carried out in aqueous solution of triton X-100, a neutral surfactant. The results show that the ionic dyes, erythrosin B and safranin O form 1:1 electron donor-acceptor (EDA) or charge-transfer (CT) complexes with triton X-100 both in the ground and excited states, whereas neutral dye riboflavin in its excited state forms 1:1 complex with triton X-100. In these complexes, the dyes act as electron acceptors whereas triton X-100 acts as an electron donor. The fluorescence spectra of erythrosin B and safranin O in presence of triton X-100 show enhancement of fluorescence intensity with red and blue shifts respectively while riboflavin shows normal quenching of fluorescence. A good correlation has been found among photovoltage generation of the systems consisting of these dyes and triton X-100, spectral shift due to complex formation and thermodynamic properties of these complexes.

  9. Scanning probe microscopy studies on the adsorption of selected molecular dyes on titania

    Directory of Open Access Journals (Sweden)

    Jakub S. Prauzner-Bechcicki

    2016-11-01

    Full Text Available Titanium dioxide, or titania, sensitized with organic dyes is a very attractive platform for photovoltaic applications. In this context, the knowledge of properties of the titania–sensitizer junction is essential for designing efficient devices. Consequently, studies on the adsorption of organic dyes on titania surfaces and on the influence of the adsorption geometry on the energy level alignment between the substrate and an organic adsorbate are necessary. The method of choice for investigating the local environment of a single dye molecule is high-resolution scanning probe microscopy. Microscopic results combined with the outcome of common spectroscopic methods provide a better understanding of the mechanism taking place at the titania–sensitizer interface. In the following paper, we review the recent scanning probe microscopic research of a certain group of molecular assemblies on rutile titania surfaces as it pertains to dye-sensitized solar cell applications. We focus on experiments on adsorption of three types of prototypical dye molecules, i.e., perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA, phtalocyanines and porphyrins. Two interesting heteromolecular systems comprising molecules that are aligned with the given review are discussed as well.

  10. Adsorption studies on treatment of textile dyeing industrial effluent by flyash

    Energy Technology Data Exchange (ETDEWEB)

    Rao, V.V.B.; Rao, S.R.M. [Osmania University, Hyderabad (India). College of Technology

    2006-02-01

    Textile effluents are highly toxic as they contain a large number of metal complex dyes. The high concentration of such dyes causes many water borne diseases and increases the BOD of the receiving waters. On the other hand, flyash is a major pollutant generated in coal-based thermal power plants and has potentiality for use as an adsorbent. In the present work, adsorption studies were made in treating the dye solutions of methylene blue and Congo red textile dyes by using flyash. Effects of quantity of adsorbent, time of contact, initial effluent concentration, pH and temperature have been investigated experimentally and the results were compared with those obtained by using activated carbon. The first-order adsorption rate constants were determined and found decreasing with temperature. The results obtained were fitted by Langmuir model since monolayer formation observed. Also, Langmuir adsorption isotherm parameters were estimated from the experimental data obtained for both methylene blue and Congo red dyes using both the adsorbents.

  11. Case study of the sonochemical decolouration of textile azo dye Reactive Black 5

    Energy Technology Data Exchange (ETDEWEB)

    Vajnhandl, Simona [University of Maribor, Faculty of Mechanical Engineering, Smetanova 17, 2000 Maribor (Slovenia)]. E-mail: simona.vajnhandl@uni-mb.si; Le Marechal, Alenka Majcen [University of Maribor, Faculty of Mechanical Engineering, Smetanova 17, 2000 Maribor (Slovenia)

    2007-03-06

    The decolouration and mineralization of reactive dye C.I. Reactive Black 5, a well-known representative of non-biodegradable azo dyes, by means of ultrasonic irradiation at 20, 279 and 817 kHz has been investigated with emphasis on the effect of various parameters on decolouration and degradation efficiency. Characterization of the used ultrasound systems was performed using calorimetric measurements and oxidative species monitoring using Fricke and iodine dosimeter. Experiments were carried out with low frequency probe type, and a high-frequency plate type transducer at 50, 100 and 150 W of acoustic power and within the 5-300 mg/L initial dye concentration range. Decolouration, as well as radical production, increased with increasing frequency, acoustic power, and irradiation time. Any increase in initial dye concentration results in decreased decolouration rates. Sonochemical decolouration was substantially depressed by the addition of 2-methyl-2-propanol as a radical scavenger, which suggests radical-induced reactions in the solution. Acute toxicity to marine bacteria Vibrio fischeri was tested before and after ultrasound irradiation. Under the conditions employed in this study, no toxic compounds were detected after 6 h of irradiation. Mineralization of the dye was followed by TOC measurements. Relatively low degradation efficiency (50% after 6 h of treatment) indicates that ultrasound is rather inefficient in overall degradation, when used alone.

  12. Kinetics study of ultrafast electron transfer from sensitized dyes to silver halide microcrystals

    Institute of Scientific and Technical Information of China (English)

    Yang Shao-Peng; Fan Guo-Zhi; Fan Shan-Shan; Cao Ning; Li Xiao-Wei; Jiang Xiao-Li; Fu Guang-Sheng

    2006-01-01

    Spectral sensitization micromechanism of cyanine dyes J-aggregate adsorbed on the tabular and cubic AgBr microcrystals with different dye concentrations is studied by using picosecond time-resolved fluorescence spectroscopy,and the dependences of electron transfer and spectral efficiency sensitization on different conditions are analysed in detail. With the steady spectroscopy, the wavelengths of absorption and fluorescence of J-aggregate adsorbed on AgBr microcrystals are found to shift to red relative to dye monomer. The spectrum of fluorescence has a red shift relative to the absorption peak. With the time-resolved fluorescence spectroscopy, the fluorescence decay curves of cyanine dyes J-aggregate adsorbed on the tabular and cubic AgBr grains are found to be fitted well by a double-exponential decay function. The fitting curves consist of a fast and a slow component. Because of the large amplitude of the fast component, this fast decay should be attributable mainly to the electron transfer from J-aggregate of dye to a conduction band of AgBr.

  13. Longitudinal diffusion behavior of hemicyanine dyes across phospholipid vesicle membranes as studied by second-harmonic generation and fluorescence spectroscopies.

    Science.gov (United States)

    Yamaguchi, Akira; Nakano, Masaki; Nochi, Kimihisa; Yamashita, Tomohisa; Morita, Kotaro; Teramae, Norio

    2006-10-01

    The adsorption and longitudinal diffusion behaviors of a series of hemicyanine dyes to phospholipid vesicle membranes were studied by second-harmonic generation (SHG) and fluorescence spectroscopies. It was observed that the longitudinal diffusion of cationic hemicyanine dyes takes place immediately after the initial adsorption of these dyes to the outer surface of the vesicle membrane. In contrast, hardly any amount of a zwitterionic hemicyanine dye with a sulfonate group diffused across the vesicle membrane within the measurement time (<2000 s). Based on the difference in the time-course responses of SHG and fluorescence spectroscopies for all of the hemicyanine dyes tested, we propose that hydration of the sulfonate group is mainly responsible for the low diffusivity of the zwitterionic hemicyanine dye.

  14. DFT and TD-DFT study on geometries, electronic structures and electronic absorption of some metal free dye sensitizers for dye sensitized solar cells.

    Science.gov (United States)

    Mohr, T; Aroulmoji, V; Ravindran, R Samson; Müller, M; Ranjitha, S; Rajarajan, G; Anbarasan, P M

    2015-01-25

    The geometries, electronic structures, polarizabilities and hyperpolarizabilities of 2-hydroxynaphthalene-1,4-dione (henna1), 3-(5-((1E)-2-(1,4-dihydro-1,4-dioxonaphthalen-3-yloxy) vinyl) thiophen-2-yl)-2-isocyanoacrylic acid (henna2) and anthocyanin dye sensitizers were studied based on density functional theory (DFT) using the hybrid functional B3LYP. The Ultraviolet-Visible (UV-Vis) spectrum was investigated by using a hybrid method which combines the properties and dynamics of many-body in the presence of time-dependent (TD) potentials, i.e. TDSCF-DFT (B3LYP). Features of the electronic absorption spectrum in the visible and near-UV regions were plotted and assigned based on TD-DFT calculations. Due to the absorption, bands of the metal-organic compound are n→π(*) present. The calculated results suggest that the three lowest energy excited states of the investigated dye sensitizers are due to photoinduced electron transfer processes. The interfacial electron transfer between semiconductor TiO2 electrode and dye sensitizer is owing to an electron injection process from excited dye to the semiconductor's conduction band. The role of linking the henna1 dye with a carboxylic acid via a thiophene bridge was analyzed. The results are that using a stronger π-conjugate bridge as well as a strong donator and acceptor group enhances the efficiency.

  15. Nonlinear optical properties of natural laccaic acid dye studied using Z-scan technique

    Science.gov (United States)

    Zongo, S.; Sanusi, K.; Britton, J.; Mthunzi, P.; Nyokong, T.; Maaza, M.; Sahraoui, B.

    2015-08-01

    We have investigated the nonlinear optical properties, including the optical limiting behaviour for five different concentrations of laccaic acid dye in solution and a thin film obtained through doping in poly (methyl methacrylate) (PMMA) polymer. The experiments were performed by using single beam Z-scan technique at 532 nm with 10 ns, 10 Hz Nd:YAG laser pulses excitation. From the open-aperture Z-scan data, we derived that the laccaic dye samples exhibit strong two photon absorption (2PA). The nonlinear refractive index was determined through the closed aperture Z-scan data. The estimated absorption coefficient β2, nonlinear refractive index n2 and second order hyperpolarizability γ were found to be of the order of 10-10 m/W, 10-9 esu and 10-32 esu, respectively. The Z-scan study reveals that the natural laccaic acid dye emerges as a promising material for third order nonlinear optical devices application.

  16. Study on the Hydrolysis and Ammonolysis Kinetics of a Monochlorotriazinyl Reactive Dye

    Institute of Scientific and Technical Information of China (English)

    XIA Jian-ming

    2009-01-01

    To understand the reaction behaviour of the reactive dye with amino groups on protein fibres, the reaction kinetics of competitive hydrolysis and ammonolysis of a monochlorotriazina reactive dye were studied at 50 -80℃ and pH = 8 - 10 by high performance liquid chromatography (HPLC). The results showed the pseudofirst-order phenomenon for the general reaction of concurrent hydrolysis and ammonolysis of the dyes. The ammonolysis reaction was always faster than the hydrolysis reaction in the range of temperature and pH employed, but the preference for ammonolysis to hydrolysis reaction decreased with the increase of temperature and pH value. The ratios of ammonolysis/hydrolysis rate constant reduced from 17.6 to 5.4 when the temperature increased from 50 to 80℃ in pH =10, and from 7.2 to 5.4 when the pH value increased from 8 to 10 at 80℃.

  17. A kinetic study of textile dyeing wastewater degradation by Penicillium chrysogenum.

    Science.gov (United States)

    Durruty, Ignacio; Fasce, Diana; González, Jorge Froilán; Wolski, Erika Alejandra

    2015-06-01

    The potential of Penicillium chrysogenum to decolorize azo dyes and a real industrial textile wastewater was studied. P. chrysogenum was able to decolorize and degrade three azo dyes (200 mg L(-1)), either independently or in a mixture of them, using glucose as a carbon source. A kinetic model for degradation was developed and it allowed predicting the degradation kinetics of the mixture of the three azo dyes. In addition, P. chrysogenum was able to decolorize real industrial wastewater. The kinetic model proposed was also able to predict the decolorization of the real wastewater. The calibration of the proposed model makes it a useful tool for future wastewater facilities' design and for practical applications.

  18. Comparative Studies on Dyeability with Direct, Acid and Reactive Dyes after Chemical Modification of Jute with Mixed Amino Acids Obtained from Extract of Waste Soya Bean Seeds

    Science.gov (United States)

    Bhaumik, Nilendu Sekhar; Konar, Adwaita; Roy, Alok Nath; Samanta, Ashis Kumar

    2017-06-01

    Jute fabric was treated with mixed natural amino acids obtained from waste soya bean seed extract for chemical modification of jute for its cataionization and to enhance its dyeability with anionic dyes (like direct, reactive and acid dye) as well enabling soya modified jute for salt free dyeing with anionic reactive dyes maintaining its eco-friendliness. Colour interaction parameters including surface colour strength were assessed and compared for both bleached and soya-modified jute fabric for reactive dyeing and compared with direct and acid dye. Improvement in K/S value (surface colour strength) was observed for soya-modified jute even in absence of salt applied in dye bath for reactive dyes as well as for direct and acid dyes. In addition, reactive dye also shows good dyeability even in acid bath in salt free conditions. Colour fastness to wash was evaluated for bleached and soya-modified jute fabric after dyeing with direct, acid and reactive dyes are reported. Treatment of jute with soya-extracted mixed natural amino acids showed anchoring of some amino/aldemine groups on jute cellulosic polymer evidenced from Fourier Transform Infra-Red (FTIR) Spectroscopy. This amino or aldemine group incorporation in bleached jute causes its cationization and hence when dyed in acid bath for reactive dye (instead of conventional alkali bath) showed dye uptake for reactive dyes. Study of surface morphology by Scanning Electron Microscopy (SEM) of said soya-modified jute as compared to bleached jute was studied and reported.

  19. Spectral, stoichiometric ratio, physicochemical, polarity and photostability studies of newly synthesized chalcone dye in organized media

    Energy Technology Data Exchange (ETDEWEB)

    Marwani, Hadi M., E-mail: hmarwani@kau.edu.sa [Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Center of Excellence for Advanced Materials Research, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Asiri, Abdullah M. [Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Center of Excellence for Advanced Materials Research, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Khan, Salman A. [Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia)

    2013-04-15

    The main focus of this study was to investigate spectroscopic properties, stoichiometric ratios, physicochemical parameters, polarity and photostability behaviors of newly synthesized chalcone dye in organized media. The chalcone dye, 1-(2,5-Dimethyl-thiophen-3-yl)-3-(9-etnyl-9H-carbazol-3-yl)-propenone (DTEP), was prepared by the reaction of carbazole aldehyde with 3-acetyl-2,5-dimethythiophene. Data obtained from FT-IR, {sup 1}H-–NMR, {sup 13}C-NMR and elemental analysis were consistent with chemical structure of newly prepared DTEP. Increases in fluorescence intensities of DTEP with cetyltrimethyl ammonium bromide (CTAB) were observed. In comparison of fluorescence intensities for DTEP with CTAB, reductions in fluorescence intensities for DTEP with sodium dodecyl sulfate (SDS) were noticed under the same experimental and instrumental conditions. Additionally, Benesi–Hildebrand method was applied to determine stoichiometric ratios and association constants of DTEP with CTAB and SDS. Stern–Volmer plot was used in order to further confirm the stoichiometric ratio and association constant of DTEP with SDS. Physicochemical parameters such as singlet absorption, molar absorptivity, oscillator strength, dipole moment and fluorescence quantum yield of DTEP were also determined. Fluorescence polarity study displayed that DTEP was sensitive to the polarity of the microenvironment provided by different solvents. Finally, fluorescence steady-state measurements revealed that DTEP has high photostability against photobleaching. -- Highlights: ► Mechanistic understanding of molecular structure of newly synthesized chalcone dye. ► Exploring spectral behaviors and physicochemical parameters of chalcone dye. ► Determination of stoichiometric ratios and association constants of chalcone dye. ► Determination of fluorescence quantum yield in different solvents. ► High photostability against photobleaching of chalcone dye was observed.

  20. Molecular design of new hydrazone dyes for dye-sensitized solar cells: Synthesis, characterization and DFT study

    KAUST Repository

    Al-Sehemi, Abdullah G.

    2012-07-01

    Three new sensitizers 2-{4-[2-(4-Nitrobenzylidene)hydrazino)]phenyl} ethylene-1,1,2-tricarbonitrile (NBHPET), 2-{4-[2-p-Chlorobenzylidenehydrazino] phenyl}- ethylene-1,1,2-tri carbonitrile (CBHPET) and 2-{4-[2-p- Bromobenzylidenehydrazino] phenyl}ethylene-1,1,2-tricarbonitrile (BBHPET) have been synthesized. The dyes showed pronounced solvatochromic effects as the polarity of the solvents increased. The structures have been optimized at B3LYP/6-31G(d) level of theory. The torsion in E-isomer is smaller than Z-isomer and azo isomers. The highest occupied molecular orbitals are delocalized on whole molecule while lowest unoccupied molecular orbitals are distributed on the tricarbonitrile. The lowest unoccupied molecular orbital energies are above the conduction band of titanium dioxide, highest occupied molecular orbitals of the dyes are below the redox couple of new synthesized dyes and small energy gap revealed these dyes would be better sensitizers for dye-sensitized solar cells. © 2012 Elsevier B.V. All rights reserved.

  1. A combined spectroscopic and TDDFT study of natural dyes extracted from fruit peels of Citrus reticulata and Musa acuminata for dye-sensitized solar cells

    Science.gov (United States)

    Prima, Eka Cahya; Hidayat, Novianto Nur; Yuliarto, Brian; Suyatman; Dipojono, Hermawan Kresno

    2017-01-01

    This study reports the novel spectroscopic investigations and enhanced the electron transfers of Citrus reticulata and Musa acuminata fruit peels as the photosensitizers for the dye-sensitized solar cells. The calculated TD-DFT-UB3LYP/6-31 + G(d,p)-IEFPCM(UAKS), experiment spectra of ultra-violet-visible spectroscopy, and Fourier transform infrared spectroscopy studies indicate the main flavonoid (hesperidin and gallocatechin) structures of the dye extracts. The optimized flavonoid structures are calculated using Density functional theory (DFT) at 6-31 + G(d,p) level. The rutinosyl group of the hesperidin pigment (Citrus reticulata) will be further investigated compared to the gallocatechin (Musa acuminata) pigment. The acidity of the dye extract is treated by adding 2% acetic acid. The energy levels of the HOMO-LUMO dyes are measured by a combined Tauc plot and cyclic voltammetry contrasted with the DFT data. The electrochemical impedance spectroscopy will be performed to model the dye electron transfer. As for the rutinosyl group presence and the acidic treatment, the acidified Citrus reticulata cell under continuous light exposure of 100 mW·cm- 2 yields a short-circuit current density (Jsc) of 3.23 mA/cm2, a photovoltage (Voc) of 0.48 V, and a fill factor of 0.45 corresponding to an energy conversion efficiency (η) of 0.71% because the shifting down HOMO-LUMO edges and the broadening dye's absorbance evaluated by a combined spectroscopic and TD-DFT method. The result also leads to the longest diffusion length of 32.2 μm, the fastest electron transit of 0.22 ms, and the longest electron lifetime of 4.29 ms.

  2. Radioisotope tracer studies in the NASA Skylab ethothermic brazing experiment M-552

    Science.gov (United States)

    Braski, D. N.; Adair, H. L.; Kobisk, E. H.

    1974-01-01

    The first use of radioisotope tracer for mapping flow patterns during brazing of metal components in a space environment (near-zero gravity) proved successful. A nickel ferrule was brazed to a nickel tube with Lithobraze BT (71.8% Ag, 28% Cu, 0.2% Li) which contained a trace amount of radioactive Ag-110. Mapping of the flow of the braze alloy in the annulus formed between the tube and the concentric ferrule was determined by counting the radiation intensity as a function of position in the braze joint. Significant information concerning the thermal history of the braze was determined.

  3. Binding of phenazinium dye safranin T to polyriboadenylic acid: spectroscopic and thermodynamic study.

    Science.gov (United States)

    Pradhan, Ankur Bikash; Haque, Lucy; Roy, Snigdha; Das, Suman

    2014-01-01

    Here, we report results from experiments designed to explore the association of the phenazinium dye safranin T (ST, 3,7-diamino-2,8-dimethyl-5-phenylphenazinium chloride) with single and double stranded form of polyriboadenylic acid (hereafter poly-A) using several spectroscopic techniques. We demonstrate that the dye binds to single stranded polyriboadenylic acid (hereafter ss poly-A) with high affinity while it does not interact at all with the double stranded (ds) form of the polynucleotide. Fluorescence and absorption spectral studies reveal the molecular aspects of binding of ST to single stranded form of the polynucleotide. This observation is also supported by the circular dichroism study. Thermodynamic data obtained from temperature dependence of binding constant reveals that association is driven by negative enthalpy change and opposed by negative entropy change. Ferrocyanide quenching studies have shown intercalative binding of ST to ss poly-A. Experiments on viscosity measurements confirm the binding mode of the dye to be intercalative. The effect of [Na⁺] ion concentration on the binding process suggests the role of electrostatic forces in the complexation. Present studies reveal the utility of the dye in probing nucleic acid structure.

  4. Binding of phenazinium dye safranin T to polyriboadenylic acid: spectroscopic and thermodynamic study.

    Directory of Open Access Journals (Sweden)

    Ankur Bikash Pradhan

    Full Text Available Here, we report results from experiments designed to explore the association of the phenazinium dye safranin T (ST, 3,7-diamino-2,8-dimethyl-5-phenylphenazinium chloride with single and double stranded form of polyriboadenylic acid (hereafter poly-A using several spectroscopic techniques. We demonstrate that the dye binds to single stranded polyriboadenylic acid (hereafter ss poly-A with high affinity while it does not interact at all with the double stranded (ds form of the polynucleotide. Fluorescence and absorption spectral studies reveal the molecular aspects of binding of ST to single stranded form of the polynucleotide. This observation is also supported by the circular dichroism study. Thermodynamic data obtained from temperature dependence of binding constant reveals that association is driven by negative enthalpy change and opposed by negative entropy change. Ferrocyanide quenching studies have shown intercalative binding of ST to ss poly-A. Experiments on viscosity measurements confirm the binding mode of the dye to be intercalative. The effect of [Na⁺] ion concentration on the binding process suggests the role of electrostatic forces in the complexation. Present studies reveal the utility of the dye in probing nucleic acid structure.

  5. A Water Mass Tracer Detected in Aerosols Demonstrates Ocean-Atmosphere Mass Transfer and Links Sea Spray Aerosol to Source Waters

    Science.gov (United States)

    Pendergraft, M.; Grimes, D. J.; Giddings, S. N.; Feddersen, F.; Prather, K. A.; Santander, M.; Lee, C.; Beall, C.

    2016-12-01

    During September and October of 2015 the Cross Surfzone/Inner-shelf Dye Exchange (CSIDE) project released rhodamine WT dye to study nearshore water movement and exchange offshore along a Southern California sandy beach. We utilized this opportunity to investigate ocean-atmosphere mass transfer via sea spray aerosol and linkage to source waters. Aerosol-concentrating sampling equipment was deployed at beachside and inland locations during three dye releases. Concentrated aerosol samples were analyzed for dye content using fluorescence spectroscopy. Here we present the ocean and atmosphere conditions associated with the presence and absence of dye in aerosol samples. Dye was identified in aerosol samples collected 0.1-0.3 km from the shoreline for 6 hs during the first and third dye releases of the CSIDE project. During these releases the dye persisted in the waters upwind of the sampling equipment. Dye was not detected in aerosol samples collected during the second release during which dye was moved away from waters upwind of the sampling equipment. Recovery of a chemical tracer in sea spray aerosol allows direct linkage to a known source area in the ocean that is independent of, but supported by, wind data. Our observations demonstrate: a tight ocean-atmosphere spatial coupling; a short residence time of coastal marine constituents before transfer to the atmosphere; that the ocean is both a sink for and a source of atmospheric and terrestrial material; and that human inputs to the ocean can return to us in sea spray aerosol.

  6. A pilot study to assess the feasibility of using naturally-occurring radionuclides as mass balance tracers to estimate soil ingestion.

    Science.gov (United States)

    Doyle, J R; White, P A; Blais, J M

    2012-09-01

    The relatively few soil ingestion studies that have been conducted to date to support soil ingestion rate values used for contaminated site human health risk assessments (HHRAs) typically have measured mass balance elemental tracers (e.g., Al, Si, Ba, Ce, Mn, Ti, V, Zr), found in soil to estimate soil ingestion. This pilot study, involving a canine subject fed a known amount of tracer on a daily basis, assessed the use of alternative mass balance tracers, specifically naturally occurring radionuclides of the (238)U and (232)Th decay series, to estimate soil ingestion. A novel method of estimating soil ingestion via difference in isotopic ratios between the two decay series in food and soil was also assessed. The results of the study showed that the mean (214)Pb and (212)Pb activities measured in fecal samples were greater than what was contained in the soil inoculant, suggesting that the tracers were not being significantly absorbed in the GI tract. The mean daily soil ingestion rates, calculated after subtracting the contribution of tracers in the soil inoculant, were 3.9 g d(-1) (standard deviation 3.6 g d(-1)) for the isotope tracers, and 1.9 g(-1) (standard deviation 2.1 g d(-1)) for the 3 most reliable elemental tracers. The differences were not statistically significant and further evaluation of isotopic tracers for soil ingestion studies is warranted. Similarly, soil ingestion estimates calculated using the Isotope Ratio Method were not significantly different than when calculated using (212)Pb; however, the Isotope Ratio Method was observed to positively bias the soil ingestion estimates by approximately 50%. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Kajian Profil Lulusan STAIN Samarinda Program Studi Pendidikan Agama Islam (PAI Tahun 2009 – 2013 dengan Pendekatan Tracer Study

    Directory of Open Access Journals (Sweden)

    Wahdatunnisa Wahdatunnisa

    2014-06-01

    Full Text Available Islamic higher education is targeted to create a high qualified human resources. A tracer study could be used to gain a data about the flaws, both of the process of education and the process of learning, of the quality of Islamic higher educations. by knowing the flaws, it can be used to make a better planning in the future. The problem of this study are: 1 How is the appropriateness of the work-field of the alumnae and the study program of Islamic education program of IAIN Samarinda?, 2 How is the contributions of the curriculum of Islamic education program of IAIN Samarinda to the work-field?, 3 How is the improvement of curriculum of Islamic education program of IAIN Samarinda to create a high qualified alumnae? This is and evaluative research design which is objected to describe the profil of alumnae and the curriculum relevance at Islamic education program at IAIN Samarinda. In this study, the researcher used interview and documentation to collect the data. The researcher used interview guide and recording tools as the instruments. The result of the study shows that: firstly, most of alumnae work in the schools as teachers or administration staff. Secondly, curriculum of PAI at STAIN Samarinda proves in supporting the work of alumnae. Thirdly, the improvement of curriculum can be done by adjusting the content of curriculum with the work field, improving lecturers’ qualification, erlarging the practicum, empowering the alumnae with some competencies, and strengthening the subjects of teachers and educational content.

  8. 红花黄对羊毛织物的染色性能研究%Study on dyeing of wool fabrics using natural safflower yellow dye

    Institute of Scientific and Technical Information of China (English)

    黄芳; 贾艳梅

    2016-01-01

    Natural yel ow dye was extracted from carthamus tinctorious and its stabilities to mordant ions and pH were analyzed. The extracts were applied in wool dyeing and the effects of dyeing temperature and pH on K/S value of the dyed fabric were studied. The build-up property, dyeing rate, mordant performance and color fastness of the safflower yel ow dye on wool fabric were also discussed. The results showed that safflower yel ow dye was stable to weak acid, and the color tended to dark when pH=8. The safflower yel ow dye had good property for wool dyeing with a high K/S value and the color varied with the three mordants. The dyed wool fabric treated by post-mordant copper sulfate had a higher color yield as wel as a better level⁃ing property and color fastness properties.%从中药红花中提取天然染料红花黄,分析了提取产物对pH变化及媒染剂离子的稳定性。以该染料对羊毛织物进行染色,研究了染色pH及染色温度对染色织物K/S值的影响,探讨了红花黄在羊毛织物上的提升性能、上染速率、媒染特性以及染色牢度。试验表明,红花黄染料在弱酸性条件下具有良好的稳定性,pH=8时颜色变暗。红花黄色素媒染羊毛织物的色深值较高,3种媒染剂染样的色泽不同,以硫酸铜媒染得色最深,匀染性和各项色牢度均较好。

  9. Studies on the relation between bladder cancer and benzidine or its derived dyes in Shanghai.

    Science.gov (United States)

    You, X Y; Chen, J G; Hu, Y N

    1990-08-01

    Shanghai is the largest industrial centre in China and has a history of about 50 years in producing and applying benzidine derived dyes. A series of epidemiological studies on the carcinogenicity of benzidine and its derived dyes have been performed since 1979. This report describes three such studies. A case-control study was carried out on 344 cases of bladder cancer, each matched for age and sex, with a person without bladder cancer. Factors studied were occupational exposure, smoking, drinking, medical histories, and family history of bladder cancer and other carcinomas. The correlation between bladder cancer and occupational exposures (relative risk (RR) 5.71) was greater than that between bladder cancer and smoking (RR 1.53). A retrospective cohort study was conducted in seven dyestuffs factories where benzidine had served as an intermediate in the manufacture of dyes before 1976. The cohort was made up of 550 men and 186 women. The men were divided into two groups according to job; 354 were assigned to a presynthesis group and 196 to a postsynthesis group. Those in the presynthesis group were thought to have been exposed to benzidine and the subjects in the postsynthesis group were exposed mainly to its derived dyes. The 15 cases of bladder cancer diagnosed were all in the presynthesis group, although an excess of bladder cancer was also seen in the whole cohort. The standardised incidence ratio (SIR) of bladder cancer was 1918 in the whole cohort and 3500 in the presynthesis group. Moreover, the SIR of bladder cancer in a subgroup working directly with the assignment, transport, and mixing of benzidine was as high as 7500. A further retrospective cohort study was made on incidence of cancer among 1420 workers who used benzidine derived dyes in 43 textile printing and dyeing factories. No excess carcinoma was found. These results suggest that, in Shanghai, the main cause of bladder cancer is occupational exposure, especially to benzidine. The risk of bladder

  10. Numerical simulation of a natural gradient tracer experiment for the natural attenuation study: flow and physical transport.

    Science.gov (United States)

    Julian, H E; Boggs, J M; Zheng, C; Feehley, C E

    2001-01-01

    Results are presented for numerical simulations of ground water flow and physical transport associated with a natural gradient tracer experiment conducted within a heterogeneous alluvial aquifer of the Natural Attenuation Study (NATS) site near Columbus, Mississippi. A principal goal of NATS is to evaluate biogeochemical models that predict the rate and extent of natural biodegradation under field conditions. This paper describes the initial phase in the model evaluation process, i.e., calibration of flow and physical transport models that simulate conservative bromide tracer plume evolution during NATS. An initial large-scale flow model (LSM) is developed encompassing the experimental site and surrounding region. This model is subsequently scaled down in telescopic fashion to an intermediate-scale ground water flow model (ISM) covering the tracer-monitoring network, followed by a small-scale transport model (SSM) focused on the small region of hydrocarbon plume migration observed during NATS. The LSM uses inferred depositional features of the site in conjunction with hydraulic conductivity (K) data from aquifer tests and borehole flowmeter tests to establish large-scale K and flow field trends in and around the experimental site. The subsequent ISM incorporates specified flux boundary conditions and large-scale K trends obtained from the calibrated LSM, while preserving small-scale K structure based on some 4000 flowmeter data for solute transport modeling. The configuration of the ISM-predicted potentiometric surface approximates that of the observed surface within a root mean squared error of 0.15 m. The SSM is based on the dual-domain mass-transfer approach. Despite the well-recognized difficulties in modeling solute transport in extremely heterogeneous media as found at the NATS site, the dual-domain model adequately reproduced the observed bromide concentration distributions. Differences in observed and predicted bromide concentration distributions are

  11. In Vitro Polarized Resonance Raman Study of N719 and N719-TBP in Dye Sensitized Solar Cells

    DEFF Research Database (Denmark)

    Hassig, Søren; Jernshøj, Kit; Phuong, Nguyen Tuyet;

    2016-01-01

    The working efficiency of dye-sensitized solar cells (DSCs) depends on the long-term stability of the dye itself and on the microscopic structure of the dye-semiconductor interface. Previous experimental studies of DSCs based on ruthenium dye with bipyridine ligands (N719) adsorbed to the TiO2......substrate applied FTIR,un-polarized Raman (RS) and un-polarized resonance Raman (RRS) spectroscopy. In the un-polarized RRS studies of N719/TiO2 – DSCs the discussion of the adsorption of N719 was based on the rather weak carbonyl or carboxyl group stretching vibrations and on minor spectral changes...... of overlapping Raman modes, whereas conclusions about the dye-stability was based on the observation that fresh and aged DSCs had almost identical RRS spectra. In the present paper we address the problems mentioned above, by utilizing the unique property of Raman scattering that the polarization of the scattered...

  12. A study by non-isothermal thermal methods of spruce wood bark materialss after their application for dye removal

    Directory of Open Access Journals (Sweden)

    VIORICA DULMAN

    2005-11-01

    Full Text Available This paper deals with a study of some materials obtained from spruce bark (Picea abies, Romania, after retention of some dyes frequently used in dyeing processes in the textile industry and waste water treatment. These materials obtained by dye retention exhibit a particular thermal behavior which is different from that of the blank sample (spruce bark. The characteristic temperatures, weight losses, the residue remaining after thermo-oxidative degradation, as well as the activation energies of the significant thermo-destruction stages, estimated from non-isothermal thermogravimetric data, together with the thermal quantities calculated from DTAdata support the conclusion presented in a previous study on dye retention from aqueous solution. The obtained results made evident that, under optimal retention conditions, spruce bark shows the highest retention capacity for the Basic Blue dye, followed by Direct Brown 95 and Direct Brown 2.

  13. Dyeing of Polyester with Disperse Dyes: Part 2. Synthesis and Dyeing Characteristics of Some Azo Disperse Dyes for Polyester Fabrics

    Directory of Open Access Journals (Sweden)

    Alya M. Al-Etaibi

    2016-06-01

    Full Text Available The goal of this study was to utilize carrier for accelerating the rate of dyeing not only to enhance dyeing of polyester fabrics dyed with disperse dyes 3a,b, but also to save energy. Both the color strength expressed as dye uptake and the fastness properties of the dyed fabrics were evaluated.

  14. The Art of Tomographic Tracer Tests

    Science.gov (United States)

    Cirpka, O. A.; Leven, C.; Doro, K. O.; Sanchez-Leon, E. E.

    2015-12-01

    In tracer tomography several tracer tests are performed within an aquifer and breakthrough curves are observed at multiple observation points. In the analysis, hydraulic conductivity is estimated as spatially variable, 3-D field subject to some smoothness constraint. Coupled flow and transport models using this conductivity fields are requested to meet observed tracer data. The approach can be combined with hydraulic tomography.We have performed hydraulic-tomography and tracer-tomography tests using heat and fluorescein as tracers at a field site close to Tübingen, Germany. The aquifer consists of 8-9m alluvials sands and gravels overlain by 1-2m alluvial fines. The hydraulic setup consists of a forced flow field between an injection/extraction well couple, embedded in the forced flow field of another well couple. By turning injection to extraction wells, and vice versa, two different flow fields were considered. Injection wells were separated into several sections by packers, and water was injected into each section proportional to its transmissivity. The water injected into one of the sections contained the tracer. Multi-level observation wells were equiped with thermometers (for heat-tracer tests), on-line fluoremeters (for teh dye tracers), and pressure transducers. Processing of the breakthrough curves included data cleaning, non-parametric deconvolution, and calculation of temperal moments of the estimated transfer functions.The joint inversion of hydraulic-head measurements and temporal moments of heat-tracer transfer functions was done by the quasi-linear geostatistical approach on a computing cluster. As alternative, we directly invert the time series (without temporal moments) by Ensemble-Kalman filtering.The high diffusion coefficient of temperature diminishes the penetration of the heat-tracer into the aquifer, which can partially be compensated by reverting the flow field and repeating the tracer tests. In tests with fluorscent tracers the signal

  15. Study on a Cosmic-ray-produced Silicon-32 as a Tracer for Ocean Processes

    Directory of Open Access Journals (Sweden)

    ZHOU Peng

    2015-01-01

    Full Text Available The isotope silicon-32, with a half-life of approximately 150 years, is a cosmic-ray-produced radioactive nuclide in the atmosphere. Due to its single source and the relatively constant production rate, silicon-32 with its chemical and biological characteristics like the other stable silicon isotopes always has been seen as an ideal clock and tracer which has the potential to fill the dating time-gap and to understand marine from 50 to 1 000 years geochemical-geophysical processes, e.g. the seawater mixing process in offshore and ocean, the geochemistry and cycle of silica in estuary and ocean, the particles mixing process in the deep sea bed, as well as the estimation of the sediment deposition rate and the establishment of the time-sequence to reflect the past marine environmental changes.

  16. A Study on sediment sources in a small watershed by using REE tracer method

    Institute of Scientific and Technical Information of China (English)

    石辉; 田均良; 刘普灵; 周佩华

    1997-01-01

    In simulation experiments, rare earth element (REE) tracer method was first used to sludy the sources of sediment yield in a small watershed. The experimental results have shown that the chief parts of sediment sources are constantly changing with the development of gullies. The cutting erosion plays a major role in the primary stage of watershed development. Slope erosion intensity increased gradually with gully development of the watershed, while gully erosion intensity decreased. Similar process was also observed in an individual rainfall. The simulation experiments have shown that the method can satisfactorily interpret the origins of sediment yield of a small watershed on an effective way. The simulation experiments have also provided basic information for field researches.

  17. Study of organic N transformation in red soils by 15N tracer method

    Institute of Scientific and Technical Information of China (English)

    YeQing-Fu; ZhangQin-Zheng; 等

    1997-01-01

    Uniformly 15N-labelled ryegrass was used to investigate NH4+-production,microbial transformation and humification of organic N in two types of red soils by incubating the soils amended with labelled material.The results showed that there was little significant difference in biomass N transformation in the tested solis between 15N tracer method and conventional method,but the amount of NH4++-N released form the ryegrass in the clayey soil than in the sandy soil at all sampling time .By 120d of incubation,humified N was less than 10% of the amount of the applied N in two types of red soils and the amount of residual N in the clayey red soil was obviously higher than that in the sandy red soil.

  18. PET Radiopharmaceuticals for Imaging Integrin Expression: Tracers in Clinical Studies and Recent Developments

    Directory of Open Access Journals (Sweden)

    Roland Haubner

    2014-01-01

    Full Text Available Noninvasive determination of integrin expression has become an interesting approach in nuclear medicine. Since the discovery of the first 18F-labeled cyclic RGD peptide as radiotracer for imaging integrin αvβ3 expression in vivo, there have been carried out enormous efforts to develop RGD peptides for PET imaging. Moreover, in recent years, additional integrins, including α5β1 and αvβ6, came into the focus of pharmaceutical radiochemistry. This review will discuss the tracers already evaluated in clinical trials and summarize the preliminary outcome. It will also give an overview on recent developments to further optimize the first-generation compounds such as [18F]Galacto-RGD. This includes recently developed 18F-labeling strategies and also new approaches in 68Ga-complex chemistry. Furthermore, the approaches to develop radiopharmaceuticals targeting integrin α5β1 and αvβ6 will be summarized and discussed.

  19. Tracking the fate of nitrate through pulse-flow wetlands: A mesocosm scale 15N enrichment tracer study

    Science.gov (United States)

    Messer, Tiffany L.; Burchell, Michael R.; Böhlke, John Karl; Tobias, Craig R.

    2017-01-01

    Quantitative information about the fate of applied nitrate (NO3-N) in pulse-flow constructed wetlands is essential for designing wetland treatment systems and assessing their nitrogen removal services for agricultural and stormwater applications. Although many studies have documented NO3-N losses in wetlands, controlled experiments indicating the relative importance of different processes and N sinks are scarce. In the current study, 15NO3-N isotope enrichment tracer experiments were conducted in wetland mesocosms of two different wetland soil types at two realistic agricultural NO3-N source loads. The 15N label was traced from the source NO3-N into plant biomass, soil (including organic matter and ammonium), and N-gas constituents over 7–10 day study periods. All sinks responded positively to higher NO3-N loading. Plant uptake exceeded denitrification 2–3 fold in the low NO3-N loading experiments, while both fates were nearly equivalent in the high loading experiments. One to two years later, soils largely retained the assimilated tracer N, whereas plants had lost much of it. Results demonstrated that plant and microbial assimilation in the soil (temporary N sinks) can exceed denitrification (permanent N loss) in pulse-flow environments and must be considered by wetland designers and managers for optimizing nitrogen removal potential.

  20. A new method for studying water mass origins on basin scales: using multiple passive tracers to study Atlantic Cold Tongue variability

    Science.gov (United States)

    White, Rachel

    2015-04-01

    Multiple passive tracers are used in a dynamical ocean model to demonstrate a new method to study water mass origins on a basin-wide scale. This method has previously only been used in estuary-scale studies. A case study is chosen to highlight when this multiple passive tracer method may provide benefits over the standard method of tracing water mass origins on basin-scales: using a single passive tracer in an adjoint model. 31 passive tracers are used to determine the origin regions of the Atlantic cold tongue (ACT). At the time of the ACT minimum in sea surface temperature, 38 ± 3% of the surface water in the central equatorial Atlantic is found to originate in the western side of the basin, with 11 ± 2% originating in the east. The multiple passive tracer method can show how origin regions change with time, allowing seasonal differences in origin regions to be discerned. The identification of origin regions of cold water that increase their supply to the equatorial Atlantic in phase with the ACT cooling identifies those regions that are important to the ACT variability. Sensitivity tests show that the temporal evolution of the concentrations of such tracers within the ACT region is not sensitive to the month in which the tracers are initialised. The region of the North Brazil undercurrent is found to be the most important origin region for the central Atlantic ACT region, for a 6-8 month lead time. Using the Met Office EN4 observational dataset of ocean temperatures, correlations are found between January temperatures in the North Brazil undercurrent region and both the ACT mean temperature and ACT spatial extent in July-August, significant at the 0.95 level. This suggests that the 6-month lead-time predictability of the ACT may be increased by improved knowledge of the North Brazil undercurrent temperature. Results from previous studies suggest that such increased predictability of the ACT could potentially help improve predictions of the West African monsoon.

  1. Comparative study on reaction selectivity of azo dye decolorization by Pseudomonas luteola.

    Science.gov (United States)

    Hsueh, Chung-Chuan; Chen, Bor-Yann

    2007-03-22

    This study is to inspect how the variation of molecular structures and functional groups present in our model azo dyes (i.e., Congo red, Eriochrome black T (EBT), methyl orange, and methyl red) affects biodecolorization capability of Pseudomonas luteola. The most viable decolorization was found at pH 7-9 and the optimal cellular age for the most effective decolorization was 7 days after static incubation in dye-free cultures. In decolorization, the maximal absorption wavelength in UV-vis spectra for the different dye-containing cultures shifted from visible light range towards the ultraviolet visible range. Methyl red was not decolorized in contrast to methyl orange, Congo red, and Eriochrome black T. The sulfonic group para to azo bond (-N=N-) in methyl orange was a strong electron-withdrawing group through resonance to cause an enhancement of color removal to be easily biodecolorized. As a charged carboxyl group on methyl red is at ortho position (i.e., in the proximity) to azo bond, this led to a complete inhibition to decolorization. However, decolorization of Congo red and EBT in the absence of charged group (e.g., hydroxy or amino group) near azo bond was not completely repressed like methyl red. Thus, the presence of electron-withdrawing groups as the substituents on azo dyes enhanced decolorization capability for biodegradability. In addition, Monod kinetic model provided better predictions to all dye decolorization at initial short periods of time due to negligible intermediate formed at initial short time duration, but significant intermediate accumulation took place at longer period of time. In contrast, the decolorization performances of methyl orange at 400ppm and EBT at 230ppm were significantly less than those predicted from the Monod kinetic model likely due to accumulated intermediates exceeding the threshold levels for feedback inhibition.

  2. Application of Tracer-Injection Techniques to Demonstrate Surface-Water and Ground-Water Interactions Between an Alpine Stream and the North Star Mine, Upper Animas River Watershed, Southwestern Colorado

    Science.gov (United States)

    Wright, Winfield G.; Moore, Bryan

    2003-01-01

    Tracer-injection studies were done in Belcher Gulch in the upper Animas River watershed, southwestern Colorado, to determine whether the alpine stream infiltrates into underground mine workings of the North Star Mine and other nearby mines in the area. The tracer-injection studies were designed to determine if and where along Belcher Gulch the stream infiltrates into the mine. Four separate tracer-injec-tion tests were done using lithium bromide (LiBr), optical brightener dye, and sodium chloride (NaCl) as tracer solu-tions. Two of the tracers (LiBr and dye) were injected con-tinuously for 24 hours, one of the NaCl tracers was injected continuously for 12 hours, and one of the NaCl tracers was injected over a period of 1 hour. Concentration increases of tracer constituents were detected in water discharging from the North Star Mine, substantiating a surface-water and ground-water connection between Belcher Gulch and the North Star Mine. Different timing and magnitude of tracer breakthroughs indicated multiple flow paths with different residence times from the stream to the mine. The Pittsburgh and Sultan Mines were thought to physically connect to the North Star Mine, but tracer breakthroughs were inconclusive in water from these mines. From the tracer-injection tests and synoptic measure-ments of streamflow discharge, a conceptual model was devel-oped for surface-water and ground-water interactions between Belcher Gulch and the North Star Mine. This information, combined with previous surface geophysical surveys indicat-ing the presence of subsurface voids, may assist with decision-making process for preventing infiltration and for the remedia-tion of mine drainage from these mines.

  3. Hair dye contact allergy

    DEFF Research Database (Denmark)

    Søsted, Heidi; Rastogi, Suresh Chandra; Andersen, Klaus Ejner

    2004-01-01

    Colouring of hair can cause severe allergic contact dermatitis. The most frequently reported hair dye allergens are p-phenylenediamine (PPD) and toluene-2,5-diamine, which are included in, respectively, the patch test standard series and the hairdressers series. The aim of the present study...... was to identify dye precursors and couplers in hair dyeing products causing clinical hair dye dermatitis and to compare the data with the contents of these compounds in a randomly selected set of similar products. The patient material comprised 9 cases of characteristic clinical allergic hair dye reaction, where...... exposure history and patch testing had identified a specific hair dye product as the cause of the reaction. The 9 products used by the patients were subjected to chemical analysis. 8 hair dye products contained toluene-2,5-diamine (0.18 to 0.98%). PPD (0.27%) was found in 1 product, and m-aminophenol (0...

  4. Influence of selected fluorescent dyes on small aquatic organisms

    Science.gov (United States)

    Rowiński, Paweł; Chrzanowski, Marcin

    2011-02-01

    Rhodamine B and Rhodamine WT are fluorescent dyes commonly used as tracers in hydrological investigations. Since introducing intensely red substances into rivers raises understandable doubts of ecological nature, the authors aimed at examining the influence of these dyes on small water fauna using bioindication methods. Quantitative results, calculated with the use of Bliss-Weber probit statistical method, were achieved by means of standardized ecotoxicological tests containing ready-to-hatch resting forms of fairy shrimp (Thamnocephalus platyurus). Qualitative studies included observation of water flea crustacean (Daphnia magna) and horned planorbis snail (Planorbis corneus), both typically present in rivers and representative for temperate climate, as well as guppy fish (Poecilla reticulata), paramecium protozoan (Paramaecium caudatum) and the above-mentioned fairy shrimp. The investigation revealed that both dyes in concentrations used for hydrological purposes are low enough to exert almost no toxic impact on water fauna considered.

  5. Biodistribution study of [61Cu] pyruvaldehyde-bis (N-4-methylthiosemicarbazone) in normal rats as a PET tracer

    Institute of Scientific and Technical Information of China (English)

    Amir Reza JALILIAN; Saeed SHANESAZZADEH; Pejaman ROWSHANFARZAD; Fatemeh BOLOURINOVIN; Abbas MAJDABADI

    2008-01-01

    [61Cu]-labeled pyruvaldehyde-bis (N-4-methylthiosemicarbazone) (61Cu-PTSM), a promising agent made for imaging blood perfusion, was produced via the natZn(p,x)61Cu nuclear reaction in a 30 MeV cyclotron, and separated by a two-step column chromatography method developed in our laboratory using a cation and an anion exchange resin. After 150μA irradiation for 76 min, about 6.006 Ci of 61Cu2+ was obtained with a radiochemical separation yield of 95% and a radionuclidic purity of 99%. 61Cu-PTSM was prepared using an optimized method with in-house synthesized PTSM ligand for radiolabeling following quality control procedures using RTLC and HPLC. The tracer is mostly incorporated in heart, kidneys and brain compared to free copper cation as a control. These are in agreement with former reports. In conclusion, [61Cu]-PTSM was prepared at the radiopharmaceutical scales with high quality and is a potential PET tracer in the perfusion study of the heart, kidney, brain and tumors.

  6. Studies on the Extraction of Gold(I) Cyanide by Quaternary Ammonium Salt Using 198Au as Tracer

    Institute of Scientific and Technical Information of China (English)

    ZHANGTianxi; CHENJing; 等

    2002-01-01

    The solvent extraction of KAu(CN)2 from alkaline solution by quaternary ammonium salts (trialkylmethylammonium chloride or cetyltrimethylammonium bromide) waw investigated by means of 198Au radioactive tracer method. Various parameters,such as the gold (I) concentration in aqueous phase,the modiffer,emulsifiation at the interface of two phases, and phase ratio used in the extraction of gold (I) were studied. The results demonstrate that almost all gold (I) in the aqueous phase was practically extracted into the organic phase. The water content in the organic phase decreased significantly with increase of gold (I) concentration using long chain alcohol as modifier,in contrast with the system with tributyl phosphate (TBP) as modifier. Emulsification at the interface of two phases decreases with an increase of modifier concentration in the organic phase or with the addition of a small amount of lysozyme into the aqueous phase. The method with 198Au tracer can be directly used to determine the Au(I) concentration both in aqueous and organic phases, which is especially suitable for the low concentration of Au(I).

  7. Application of Modified Red Mud for Adsorption of Acid Orange 7 (AO7 Dye from Aqueous Solution: Isotherms, Kinetics Studies

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Zazouli

    2015-09-01

    Full Text Available Application of modified red mud for adsorption of Acid Orang 7 (AO7 dye from aqueous solution: Isotherms, Kinetics studies Abstract: Backgroud: Existence of color is one of the problems of industrial effluent such as textile industries. The dyes can be removed by various methods. Therefore, the aim of this study is evaluation of adsorption rate of acid orange (AO7 from aqueous solution by activated red mud. Material and method: This is an empirical lab study. Red mud was used as an absorbent to remove of acid orange 7 dye. The effect of various parameters on performance of absorbent was investigated and the isotherms and kinetics of adsorption was determined. The dye concentration was measured in wavelength of 452 nm by spectrophotometer. Results: The results showed that red mud surface area is 30 m2/g. The results showed that dye removal was highest at a solution pH 3 and a powder dose of 12 g/L. The AO7 removal percentage decreased from %98 to %55 at 60 min contact time when the concentration of dye was increased from 10 mg/L to 100 mg/L. The equilibrium data is best fitted on Langmuir isotherm and the adsorption kinetic model follows pseudo-second model. conclusion: The results of this study showed that red mud is able to adsorption of dye and can be used as effective and inexpensive absorbent to treat of textile effluent.

  8. Study on Dyeing of a Novel, Pro-environment Polylactic Acid (PLA) Fiber Yarn

    Institute of Scientific and Technical Information of China (English)

    FU Ke-jie; MIN Jie; LI Zheng-rong; YANG Li-sheng

    2008-01-01

    Seventeen disperse dyes including anthraquinone, azo, methine, nitro, and quinoline dyes were applied to dye the Polylactic Acid (PLA) yarns at different conditions, and the dyebath exhaustion was determined. The result shows that C.I. disperse red 167, C.I. disperse orange 30, and C.I. disperse blue 284 have dye-uptakes greater than 80%. Therefore, they can be used as the three principal dyes for PLA yams. The experiment discovered that the dyes, because of their Monoazo and ester group contents, have a higher dye-uptake for the PLA fiber. The research on the optimization of dyeing techniques suggests that PLA yarn can obtain a high level of dyeing effectiveness at the following conditions: pH 4-5, dyeing temperture 110℃ for 30- 40 min. Color fastness to perspiration, and water-washing fastness increased 1 - 1. 5 by the addition of the abstergent FB during the reduction clearing.

  9. Direct identification of early synthetic dyes: FT-Raman study of the illustrated broadside prints of José Gaudalupe Posada (1852-1913)

    Science.gov (United States)

    Casadio, F.; Mauck, K.; Chefitz, M.; Freeman, R.

    2010-09-01

    Fourier Transform (FT)-Raman spectroscopy was used for the non-invasive, direct identification of colorants used to dye historical printed papers, overcoming obstacles such as low concentration of the dye, faded colors and fluorescence interference of the aged paper substrate. Based on a newly created FT-Raman reference database of 20 widely used dyes in the 19th century paper industry, the detectability of these dyes on aged biomaterials was determined by studying dyed paper samples from contemporary dye manuals, and identifying diagnostic peaks detectable on those substrates. Lastly, the method was applied to analyze the colorants used to dye the papers of a group of prints illustrated by the influential Mexico City artist José Guadalupe Posada, active 1876-1913. Unambiguous identification of the synthetic organic colorants Malachite Green (a triarylmethane dye), Orange II and Metanil Yellow (two acid monoazo dyes), Cotton Scarlet (an acid diazo dye), Phloxine (a xanthene dye) and Victoria Blue (a triarylmethane dye) in several of Posada’s prints challenged previous art-historical assumptions that these artworks were colored with natural dyes. The acquired knowledge has important conservation implications given that aniline dyes are sensitive to light and to aqueous treatments otherwise commonly carried out on works of art on paper.

  10. Experimental and modelling investigations of tracer transport in variably saturated agricultural soil of Thailand: Column study

    Directory of Open Access Journals (Sweden)

    Tulaya Masipan

    2016-03-01

    Full Text Available Tracer (Bromide movement through the unsaturated agricultural soil was investigated in soil columns. Two tracer column experiments, with a diameter of 7 cm and a depth of 25 cm, were vertically homogeneous packed with sandy loam and then carried out to investigate bromide (Br− transport under different water contents (at steady flow condition. One soil column (Column 1 represents the unsaturated agricultural soil in dry season (with water content ranging from 0.23 to 0.26 and the other (Column 2 represents the soil in wet season (water content from 0.24 to 0.35. Bromide samples were periodically collected by vacuum tubes inserted at 6.25 cm equally spaced intervals (e.g., 6.25, 12.5, 18.75 and 25 cm along the length of the column and the effluent collected at the end of the column. The observed breakthrough curves (BTCs of bromide in both columns represented a relative smooth and sigmodal curves at different distances (sampling ports. Dispersivity (α, cm for sandy loam at different locations was numerically estimated by curve fitting the experimental data with HYDRUS-1D. The α can be well described by the convection–dispersion equation and these values derived from Column 1 (ranging from 0.37 to 0.98 cm are more than those from Column 2 (0.25–0.59. Moreover, the α in both columns increases with the travel distance due to the scale-dependent effect. Furthermore, the α values were plotted on a log–log scale against travel distances and they yield empirical power law relationships with an excellent correlation (α = 0.102 (L0.697, R2 = 0.999 and α = 0.086 (L0.579, R2 = 0.963 for Column 1 and 2, respectively.

  11. Adsorption studies of Methylene blue dye from aqueous solution onto phaseolus aureus biomaterials.

    Directory of Open Access Journals (Sweden)

    D. B. Jirekar

    2014-09-01

    Full Text Available Experimental investigation was carried out by using commercially available husk of green gram (phaseolusaureus seed to removal ofmethylene blue from aqueous medium. Husk of green gram seed was characterized by performing particle size distribution. The effect of contact time, effect of initial concentration of dye, effect of dosage, effect of salt, effect of pH, zero point pH and effect of temperature were studied in batch technique. Adsorption kinetic was verified by pseudo-first-order and pseudo-second-order models. The rate of adsorption of methylene blue followed by pseudo-second-order model for the dye concentration studied in the present case. Adsorption of methylene blue on green gram (phaseolusaureus seed husk is also followed by Langmuir and Freundlich adsorption isotherm.

  12. Computational Molecular Nanoscience Study of the Properties of Copper Complexes for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Jorge Almaral-Sánchez

    2012-11-01

    Full Text Available In this work, we studied a copper complex-based dye, which is proposed for potential photovoltaic applications and is named Cu (I biquinoline dye. Results of electron affinities and ionization potentials have been used for the correlation between different levels of calculation used in this study, which are based on The Density Functional Theory (DFT and time-dependent (TD DFT. Further, the maximum absorption wavelengths of our theoretical calculations were compared with the experimental data. It was found that the M06/LANL2DZ + DZVP level of calculation provides the best approximation. This level of calculation was used to find the optimized molecular structure and to predict the main molecular vibrations, the molecular orbitals energies, dipole moment, isotropic polarizability and the chemical reactivity parameters that arise from Conceptual DFT.

  13. Computational molecular nanoscience study of the properties of copper complexes for dye-sensitized solar cells.

    Science.gov (United States)

    Baldenebro-López, Jesús; Castorena-González, José; Flores-Holguín, Norma; Almaral-Sánchez, Jorge; Glossman-Mitnik, Daniel

    2012-11-28

    In this work, we studied a copper complex-based dye, which is proposed for potential photovoltaic applications and is named Cu (I) biquinoline dye. Results of electron affinities and ionization potentials have been used for the correlation between different levels of calculation used in this study, which are based on The Density Functional Theory (DFT) and time-dependent (TD) DFT. Further, the maximum absorption wavelengths of our theoretical calculations were compared with the experimental data. It was found that the M06/LANL2DZ + DZVP level of calculation provides the best approximation. This level of calculation was used to find the optimized molecular structure and to predict the main molecular vibrations, the molecular orbitals energies, dipole moment, isotropic polarizability and the chemical reactivity parameters that arise from Conceptual DFT.

  14. Driven tracers in narrow channels

    Science.gov (United States)

    Cividini, J.; Mukamel, D.; Posch, H. A.

    2017-01-01

    Steady-state properties of a driven tracer moving in a narrow two-dimensional (2D) channel of quiescent medium are studied. The tracer drives the system out of equilibrium, perturbs the density and pressure fields, and gives the bath particles a nonzero average velocity, creating a current in the channel. Three models in which the confining effect of the channel is probed are analyzed and compared in this study: the first is the simple symmetric exclusion process (SSEP), for which the stationary density profile and the pressure on the walls in the frame of the tracer are computed. We show that the tracer acts like a dipolar source in an average velocity field. The spatial structure of this 2D strip is then simplified to a one-dimensional (1D) SSEP, in which exchanges of position between the tracer and the bath particles are allowed. Using a combination of mean-field theory and exact solution in the limit where no exchange is allowed gives good predictions of the velocity of the tracer and the density field. Finally, we show that results obtained for the 1D SSEP with exchanges also apply to a gas of overdamped hard disks in a narrow channel. The correspondence between the parameters of the SSEP and of the gas of hard disks is systematic and follows from simple intuitive arguments. Our analytical results are checked numerically.

  15. Sodium mobility in a mini-catchment studied with radioactive tracers and artificial precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Christophersen, N.; Seip, H.M.; Qvenild, C.; Tollan, O.

    1982-01-01

    A natural 98 sq m mini-catchment was watered with artificial precipitation at an intensity of 5 mm per hour, 8 hours per day, 5 days per week for several weeks starting August 19, 1980. The tracers were administered on September 3. After 6 days an estimated 84% of the tritiated water and 45% of the Na/sup 2//sub 4/ were recovered in runoff. Na ions were fairly mobile but were delayed with respect to water movement. Some of the remaining Na/sup 24/ ions remained in stagnant zones or took part in isotopic exchange, leaving less than half of the non-radioactive Na ions available for ion exchange with ions such as H/sup +/ in the soil. Mean monthly Na ions in precipitation falling on this section of Norway averaged 15 microequivalents per liter from 1977 to 1980. The 10 microequivalents per liter Na available for ion exchange was of minor importance compared with the 50 microequivalents per liter of H..mu.. in runoff. 23 references, 3 figures, 1 table.

  16. Testing cosmic ray acceleration with radio relics: a high-resolution study using MHD and tracers

    Science.gov (United States)

    Wittor, D.; Vazza, F.; Brüggen, M.

    2017-02-01

    Weak shocks in the intracluster medium may accelerate cosmic-ray protons and cosmic-ray electrons differently depending on the angle between the upstream magnetic field and the shock normal. In this work, we investigate how shock obliquity affects the production of cosmic rays in high-resolution simulations of galaxy clusters. For this purpose, we performed a magnetohydrodynamical simulation of a galaxy cluster using the mesh refinement code ENZO. We use Lagrangian tracers to follow the properties of the thermal gas, the cosmic rays and the magnetic fields over time. We tested a number of different acceleration scenarios by varying the obliquity-dependent acceleration efficiencies of protons and electrons, and by examining the resulting hadronic γ-ray and radio emission. We find that the radio emission does not change significantly if only quasi-perpendicular shocks are able to accelerate cosmic-ray electrons. Our analysis suggests that radio-emitting electrons found in relics have been typically shocked many times before z = 0. On the other hand, the hadronic γ-ray emission from clusters is found to decrease significantly if only quasi-parallel shocks are allowed to accelerate cosmic ray protons. This might reduce the tension with the low upper limits on γ-ray emission from clusters set by the Fermi satellite.

  17. Chemical parameters as natural tracers in hydrogeology: a case study of Louros karst system, Greece

    Science.gov (United States)

    Katsanou, K.; Lambrakis, N.; D'Alessandro, W.; Siavalas, G.

    2017-03-01

    The Louros Basin hosts one of the most important karst systems of Epirus Prefecture (Greece) and plays a key role in supplying three counties with drinking water. Aiming to investigate the origin of groundwater and its flow patterns, a multi-tracer approach was used to describe and evaluate the hydrogeology of the system. Therefore, 271 surface water and groundwater samples were collected and analyzed for physicochemical parameters, major ions, and trace and rare earth elements, as well as stable isotopes (δ18O and δ2H). These data provided meaningful tracing of the water origin, water-rock interaction processes, and relationships among the aquifers. In particular, the elaboration of the major ions supported by the distribution of rare earth elements indicated that there are three aquifers located at different levels hosted in the Senonian and Pantokrator limestone formations. These aquifers are hydraulically interconnected by a cascade and constitute the Louros karst system which is drained by the homonymous river. Hydrochemical and isotopic data revealed that the Louros karst system is isolated from the adjacent northern Ioannina Basin and it is being recharged by precipitation. Higher groundwater salinity, where present, is mainly associated with increased water-rock interaction due to longer and deeper hydrologic flow, favoring the dissolution of evaporitic, carbonate and phosphate minerals.

  18. Experimental studies of healing process of rat mandibular condylar fracture, using /sup 45/Ca as tracer

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Tatsuaki (Gifu Univ. (Japan). Faculty of Medicine)

    1982-09-01

    The cervical region of the mandibular condylus of young rats was fractured. The healing process was observed pathohistologically, autoradiographically using /sup 45/Ca as a tracer, and by ultra soft roentgenography. Condylectomy of the mandibular condylus was done at the same time and its regeneration observed. The results of the observation are as follows: The fractured portion is bonded with the soft tissue 1 - 2 weeks postoperatively. Histologically, new-blood vessels in the granulation tissue and the connective tissue's change into fibers are seen. On the second week chondrocytes appeared in the neck of the capitulum mandibulae and the stump of the ascending branch. On the 3rd postoperative week, the stump of the fracture of the bone is bonded with proliferated cartilaginous tissue and an osseous bond was seen in part by autoradiograph and ultra soft x-ray picture. New bone due to periosteal ossification is seen around the stump on the ascending branch side, and the bone reconstruction with osteoclasts was seen in the inside the trabeculae. On the 4th postoperative week, osseous concrescence is observed in the fractured portion. Regeneration of the capitulum mandibulae after extirpation of the capitulum mandibulae is seen in all the cases. On the postoperative 12th week, the macroscopic form of the degenerated capitulum mandibulae which seemed to be excessive becomes almost the same morphologically with that of the contralateral side and it was observed histologically that the construction of the capitulum mandibulae is completely restored.

  19. A Case Study of the Weather Research and Forecasting Model Applied to the Joint Urban 2003 Tracer Field Experiment. Part 2: Gas Tracer Dispersion

    Science.gov (United States)

    Nelson, Matthew A.; Brown, Michael J.; Halverson, Scot A.; Bieringer, Paul E.; Annunzio, Andrew; Bieberbach, George; Meech, Scott

    2016-12-01

    The Quick Urban & Industrial Complex (QUIC) atmospheric transport, and dispersion modelling, system was evaluated against the Joint Urban 2003 tracer-gas measurements. This was done using the wind and turbulence fields computed by the Weather Research and Forecasting (WRF) model. We compare the simulated and observed plume transport when using WRF-model-simulated wind fields, and local on-site wind measurements. Degradation of the WRF-model-based plume simulations was cased by errors in the simulated wind direction, and limitations in reproducing the small-scale wind-field variability. We explore two methods for importing turbulence from the WRF model simulations into the QUIC system. The first method uses parametrized turbulence profiles computed from WRF-model-computed boundary-layer similarity parameters; and the second method directly imports turbulent kinetic energy from the WRF model. Using the WRF model's Mellor-Yamada-Janjic boundary-layer scheme, the parametrized turbulence profiles and the direct import of turbulent kinetic energy were found to overpredict and underpredict the observed turbulence quantities, respectively. Near-source building effects were found to propagate several km downwind. These building effects and the temporal/spatial variations in the observed wind field were often found to have a stronger influence over the lateral and vertical plume spread than the intensity of turbulence. Correcting the WRF model wind directions using a single observational location improved the performance of the WRF-model-based simulations, but using the spatially-varying flow fields generated from multiple observation profiles generally provided the best performance.

  20. Failure in the detection of the sentinel lymph node with a combined technique of radioactive tracer and blue dye in a patient with cancer of the vulva and a single positive lymph node

    NARCIS (Netherlands)

    Fons, G; ter Rahe, B; Sloof, G; de Hullu, J; van der Velden, J

    Background. In early stage vulvar cancer, the sentinel lymph node procedure with a radioactive tracer appears to be a promising new diagnostic tool to predict lymph node status. No detection failures have been published so far in vulvar cancer. We recently experienced failure in the detection of the

  1. Interaction of cationic dye/surfactants with Klebsiella K18 capsular polysaccharides: Physico-chemical studies

    Energy Technology Data Exchange (ETDEWEB)

    Nath, Ranendu Kumar, E-mail: rknath1959@gmail.com [Department of Chemistry, Tripura University, Suryamaninagar, Tripura-799130 (India); Singh, Th. Charanjit [Department of Chemistry, D.D.M. College, Khowai, Tripura-799 202 (India); Dasgupta, Satwati [Department of Chemistry, Tripura University, Suryamaninagar, Tripura-799130 (India); Mitra, Asish [Department of Chemistry, MBB College, Agartala, Tripura-799001 (India); Panda, Amiya Kumar [Department of Chemistry, University of North Bengal, P.O. North Bengal University, Dt: Darjeeling, West Bengal-734013 (India)

    2010-05-10

    Physico-chemical studies on the interaction of capsular polysaccharide (SPS) isolated from Klebsiella K18, with cationic dyes and surfactants have been reported. SPS is an integral component of gram-negative bacteria and having glucuronic acid as the potential anionic site, induced strong metachromasy (blue shift {approx} 110 nm) in the cationic dye pinacyanol chloride (PCYN). Reversal of metachromasy was observed upon addition of co-solvents which provides a qualitative measurement of stability and nature of metachromatic compound associated with PCYN-SPS interaction. Thermodynamic parameters such as association constant, changes in free energy, enthalpy and entropy of dye-polymer interaction, were evaluated which revealed the nature of interaction. Studies on fluorescence quenching of acridine orange (AO) was also performed. The interaction of SPS with cationic and cationic-non-ionic mixed surfactant systems have been studied by turbidimetry, spectrophotometry, spectrofluorometry and viscosity measurements. The studies could provide an understanding on the effects of the surfactants on binding with the polymer. The binding was found to be electrostatic in origin and also hydrophobic in nature to a certain extent.

  2. Process evaluation and treatability study of wastewater in a textile dyeing industry

    Directory of Open Access Journals (Sweden)

    Debabrata Mazumder

    2011-11-01

    Full Text Available The process was investigated in a textile dying unit and subsequently wastewater generation profile was studied for the development of a viable treatment. The dyeing unit under the study generated a considerable volume of wastewater containing inorganic chemicals and organic reactive green dye. Chemical oxygen demand (COD resulting from all the chemically oxidizible substances and the residual color of the dye were targeted for removal. The wastewater samples were collected from different sub-processes and then characterized for the parameters viz. pH, Total solid, Suspended solid, Dissolved solid, COD and Alkalinity. A composite wastewater sample was prepared according to the measured wastewater discharge from various unit operations and used for treatability study. In the first stage, coagulation-flocculation with alum and chemical oxidation with bleaching powder were performed separately. Subsequently, adsorption study was conducted with crushed burnt coal (C.B.C. on the composite wastewater, initially treated with 10% bleaching powder solution. After several trials, this combination was found to be effective for a C.B.C. content of 10% under a contact period of 90 minutes, which showed 100% colour and about 95% COD removal.

  3. Study on the Synthesis and Spectra of a Novel Kind of Carbozole Benzothiazole Indole Styryl Cyanine Dye with a Carbazole Bridged Chain.

    Science.gov (United States)

    Fei, Xuening; Hao, Yachao; Gu, Yingchun; Li, Chao; Yu, Lu

    2014-03-01

    Based on the frequently-used cyanine dye probe thiazole orange (TO) and Cy3, a novel kind of styryl cyanine dye was designed and synthesized. Carbazole was inserted into the structures of two cyanine dyes, TO and Cy3, to act as a bridge to link the benzothiazole and indole. This modification resulted in a novel kind of carbozole benzothiazole indole cyanine dye with a carbazole-bridged chain. The dyes were characterized by HNMR and MS. The spectra of the novel dyes were also studied and the results showed that the fluorescence wavelength of novel carbazole benzothiazole indole cyanine dye shifted red, the Stokes shift and Fluorescence quantum yields increased and the fluorescence intensity was enhanced compared to that of TO. These results indicated that the novel dye could be used as an excellent fluorescent probe in biological labeling.

  4. Study of diffusion of indocyanine green as a photodynamic dye into skin using backscattering spectroscopy

    Science.gov (United States)

    Genina, E. A.; Bashkatov, A. N.; Tuchin, V. V.

    2014-07-01

    One of the lines of development of modern medicine is theranostics consisting in simultaneous diagnosis and laser treatment with the use of multifunctional agents such as fluorescent indocyanine green that has photodynamic and photothermal properties. Diffusion of indocyanine green dissolved in water and aqueous solutions of alcohols (glycerol, propylene glycol and ethanol) into the dermis is studied by using backscattering spectroscopy. The coefficients of the dye diffusion into the dermis are obtained for the first time by using these solvents.

  5. Study of diffusion of indocyanine green as a photodynamic dye into skin using backscattering spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Genina, E A; Bashkatov, A N; Tuchin, V V [N.G. Chernyshevsky Saratov State University, Saratov (Russian Federation)

    2014-07-31

    One of the lines of development of modern medicine is theranostics consisting in simultaneous diagnosis and laser treatment with the use of multifunctional agents such as fluorescent indocyanine green that has photodynamic and photothermal properties. Diffusion of indocyanine green dissolved in water and aqueous solutions of alcohols (glycerol, propylene glycol and ethanol) into the dermis is studied by using backscattering spectroscopy. The coefficients of the dye diffusion into the dermis are obtained for the first time by using these solvents. (laser biophotonics)

  6. Spectrophotometric determination of total proteins in blood plasma: a comparative study among dye-binding methods

    OpenAIRE

    Dimas Augusto Morozin Zaia; Fábio Rangel Marques; Cássia Thaïs Bussamra Vieira Zaia

    2005-01-01

    A comparative study between the biuret method (standard method for total proteins) and spectrophotometric methods using dyes (Bradford, 3',3",5',5"-tetrabromophenolphthalein ethyl ester-TBPEE, and erythrosin-B) was carried out for the determination of total proteins in blood plasma from rats. Bradford method showed the highest sensitivity for proteins and biuret method showed the lowest. For all the methods, the absorbance for different proteins (BSA, casein, and egg albumin) was measured and...

  7. Spectral-fluorescent study of the interaction of the polymethine dye probe Cyan 2 with chondroitin-4-sulfate

    Science.gov (United States)

    Tatikolov, Alexander S.; Akimkin, Timofey M.; Panova, Ina G.; Yarmoluk, Sergiy M.

    2017-04-01

    The noncovalent interaction of the polymethine dye probe 3,3‧,9-trimethylthiacarbocyanine iodide (Cyan 2) with chondroitin-4-sulfate (C4S) in buffer solutions with different pH and in water in the absence of buffers has been studied by spectral-fluorescent methods. It has been shown that in all media studied, at relatively high concentrations, the dye is bound to C4S mainly as a monomer, which is accompanied by a steep rise of fluorescence (the intermediate formation of dye aggregates on the biopolymer is also observed). From the dependence of the fluorescence quantum yield on the concentration of C4S, the parameters of binding of the dye monomer to C4S were obtained: the effective binding constant K, the number of the monomeric C4S units n per one dye monomer bound to C4S, and the fluorescence quantum yield of the bound dye monomer Φfb. The dependence of Φfb (and K) on pH of the medium is not monotonic: it has a minimum in the region of neutral pH and a growth in the regions of acid and basic pH. This can be explained by changing the charge of a C4S macromolecule as a function of pH and related conformational alterations in the biopolymer, which can affect the rigidity of a dye molecule and the energy of its interaction with the biopolymer.

  8. Comparative Study of Photokinetics of Reduction of Toluidine Blue and Red Mct Dyes with Allylurea

    Directory of Open Access Journals (Sweden)

    *M. Qadri

    2014-03-01

    Full Text Available The reaction between Toluidine blue (TB and Red MCT dyes (reactive red monochlorotriazine dyes – MCT with allylurea (AU has been studied in an unbuffered, acidic and basic medium. Wavelength of 625 nm is set for TB and AU and 535 nm for Red MCT and AU mechanism spectrophotometrically. The kinetics were monitored by variations of the concentrations of the dyes, the reductant (AU, acid (HCl and base (NaOH consecutively under the influence of various ions of textile industrial waste. The reaction mechanism was third order kinetics with Red MCT-AU system. Whereas second order kinetics in the case of TB-AU system. The oxidation reaction of AU with TB, the cations showed suppressed effect. The trend with cations exhibited Na+>K+>Ca2+>Mg2+ behavior whereas in the presence of anions the dye decoloration was more prominent, the trend followed HCO3->CO32->Cl- behavior. The oxidation reaction of AU with red MCT, enhanced in the presence of cations. The trend with cationic effect was shown as Na+>K+> Mg2+ Ca2+, whereas the influence of anions was not appreciable. the trend with anions was HCO3-~ CO32->NO3- >Cl-. Dyes were investigated at different temperatures, and activation parameters were evaluated for a Red MCT-AU reaction and TB-AU. The values obtained for energy of activation (Ea= 32.341 kJ.mol-1 and 1.214 kJ.mol-1, enthalpy change (∆H=29.905 kJ.mol-1 and 12.90 kJ.mol-1, entropy change (∆S=-206.96 J.mol-1.K-1 and -224.57 J.mol-1.K-1, and Gibbs energy change (∆G = 90.544 kJ.mol-1 and 80.95 kJ.mol-1 respectively. Mechanisms of interaction of related ions involved in dye bleaching and reduction is proposed.

  9. Technetium-99m labelled heparin: potential value as a tracer of heparin activity in pharmacokinetic and biodistribution studies

    Energy Technology Data Exchange (ETDEWEB)

    Perdrisot, R.; Barbu, M.; Bok, B.; Berthelot, J.L.; Mazoyer, B.; Colas-Linhart, N. (Laboratoire de Biophysique des Traceurs, Faculte 10-Bichat, 75 - Paris (France))

    1984-01-01

    Pharmacokinetics and biodistribution of 99m Technetium (sup(99m)Tc) labelled heparin were studied to assess its value as a tracer of heparin kinetics in comparison with unlabelled heparin. In vitro, the stability and labelling efficiency (98%) of the labelled drug were excellent and elution was minimal. In vivo, after I.V. infusion of the drug, there was no difference in the same animal between anticoagulant activity measurements and radioactive countings, both displaying a plasmatic biexponential pattern (T/sub 1/=2.9 minutes, T/sub 2/=76 minutes). Biodistribution studies showed primarily liver, spleen and kidney accumulation, with no thyroid uptake. The advantages of this technetium labelling may therefore be used for the heparin drug in various experimental and pathological situations even in humans.

  10. Analysis of tracer and thermal transients during reinjection

    Energy Technology Data Exchange (ETDEWEB)

    Kocabas, I.

    1989-10-01

    This work studied tracer and thermal transients during reinjection in geothermal reserviors and developed a new technique which combines the results from interwell tracer tests and thermal injection-backflow tests to estimate the thermal breakthrough times. Tracer tests are essential to determine the degree of connectivity between the injection wells and the producing wells. To analyze the tracer return profiles quantitatively, we employed three mathematical models namely, the convection-dispersion (CD) model, matrix diffusion (MD) model, and the Avodnin (AD) model, which were developed to study tracer and heat transport in a single vertical fracture. We considered three types of tracer tests namely, interwell tracer tests without recirculation, interwell tracer tests with recirculation, and injection-backflow tracer tests. To estimate the model parameters, we used a nonlinear regression program to match tracer return profiles to the solutions.

  11. Tracer tomography (in) rocks!

    Science.gov (United States)

    Somogyvári, Márk; Jalali, Mohammadreza; Jimenez Parras, Santos; Bayer, Peter

    2016-04-01

    Physical behavior of fractured aquifers is rigorously controlled by the presence of interconnected conductive fractures, as they represent the main pathways for flow and transport. Ideally, they are simulated as a discrete fracture network (DFN) in a model to capture the role of fracture system geometry, i.e. fracture length, height, and width (aperture/transmissivity). Such network may be constrained by prior geological information or direct data resources such as field mapping, borehole logging and geophysics. With the many geometric features, however, calibration of a DFN to measured data is challenging. This is especially the case when spatial properties of a fracture network need to be calibrated to flow and transport data. One way to increase the insight in a fractured rock is by combining the information from multiple field tests. In this study, a tomographic configuration that combines multiple tracer tests is suggested. These tests are conducted from a borehole with different injection levels that act as sources. In a downgradient borehole, the tracer is recorded at different levels or receivers, in order to maximize insight in the spatial heterogeneity of the rock. As tracer here we chose heat, and temperature breakthrough curves are recorded. The recorded tracer data is inverted using a novel stochastic trans-dimensional Markov Chain Monte Carlo procedure. An initial DFN solution is generated and sequentially modified given available geological information, such as expected fracture density, orientation, length distribution, spacing and persistency. During this sequential modification, the DFN evolves in a trans-dimensional inversion space through adding and/or deleting fracture segments. This stochastic inversion algorithm requires a large number of thousands of model runs to converge, and thus using a fast and robust forward model is essential to keep the calculation efficient. To reach this goal, an upwind coupled finite difference method is employed

  12. Evaluation of short-term tracer fluctuations in groundwater and soil air in a two year study

    Science.gov (United States)

    Jenner, Florian; Mayer, Simon; Aeschbach, Werner; Weissbach, Therese

    2016-04-01

    The application of gas tracers like noble gases (NGs), SF6 or CFCs in groundwater studies such as paleo temperature determination requires a detailed understanding of the dynamics of reactive and inert gases in the soil air with which the infiltrating water equilibrates. Due to microbial gas consumption and production, NG partial pressures in soil air can deviate from atmospheric air, an effect that could bias noble gas temperatures estimates if not taken into account. So far, such an impact on NG contents in groundwater has not been directly demonstrated. We provide the first long-term study of the above mentioned gas tracers and physical parameters in both the saturated and unsaturated soil zone, sampled continuously for more than two years near Mannheim (Germany). NG partial pressures in soil air correlate with soil moisture and the sum value of O2+CO2, with a maximal significant enhancement of 3-6% with respect to atmospheric air during summer time. Observed seasonal fluctuations result in a mass dependent fractionation of NGs in soil air. Concentrations of SF6 and CFCs in soil air are determined by corresponding fluctuations in local atmospheric air, caused by industrial emissions. Arising concentration peaks are damped with increasing soil depth. Shallow groundwater shows short-term NG fluctuations which are smoothed within a few meters below the water table. A correlation between NG contents of soil air and of groundwater is observable during strong recharge events. However, there is no evidence for a permanent influence of seasonal variations of soil air composition on shallow groundwater. Fluctuating NG contents in shallow groundwater are rather determined by variations of soil temperature and water table level. Our data gives evidence for a further temperature driven equilibration of groundwater with entrapped air bubbles within the topmost saturated zone, which permanently occurs even some years after recharge. Local subsurface temperature fluctuations

  13. Modeling of meteorology, tracer transport and chemistry for the Uintah Basin Winter Ozone Studies 2012 and 2013

    Science.gov (United States)

    Ahmadov, R.; McKeen, S. A.; Angevine, W. M.; Frost, G. J.; Roberts, J. M.; De Gouw, J. A.; Warneke, C.; Peischl, J.; Brown, S. S.; Edwards, P. M.; Wild, R. J.; Pichugina, Y. L.; Banta, R. M.; Brewer, A.; Senff, C. J.; Langford, A. O.; Petron, G.; Karion, A.; Sweeney, C.; Schnell, R. C.; Johnson, B.; Zamora, R. J.; Helmig, D.; Park, J.; Evans, J.; Stephens, C. R.; Olson, J. B.; Trainer, M.

    2013-12-01

    The Uintah Basin Winter Ozone Studies (UBWOS) field campaigns took place during winter of 2012 and 2013 in the Uintah Basin, Utah. The studies were aimed at characterizing meteorology, emissions of atmospheric constituents and air chemistry in a region abundant with oil and gas production, with associated emissions of various volatile organic compounds (VOCs) and NOx. High ozone pollution events were observed throughout the Uintah Basin during the winter of 2013, but not during the winter of 2012. A clear understanding of the processes leading to high ozone events is still lacking. We present here high spatiotemporal resolution simulations of meteorology, tracer transport and gas chemistry over the basin during January-February, 2012 and 2013 using the WRF/Chem regional photochemical model. Correctly characterizing the meteorology poses unique challenges due to complex terrain, cold-pool conditions, and shallow inversion layers observed during the winter of 2013. We discuss the approach taken to adequately simulate the meteorology over the basin and present evaluations of the modeled meteorology using surface, lidar and tethersonde measurements. Initial simulations use a passive tracer within the model as a surrogate for CH4 released from oil and gas wells. These tracer transport simulations show that concentrations of inert, emitted species near the surface in 2013 were 4-8 times higher than 2012 due to much shallower boundary layers and reduced winds in 2013. This is supported by in-situ measurements of CH4 made at the Horse Pool surface station during the field campaigns. Full photochemical simulations are forced by VOC and NOx emissions that are determined in a top-down approach, using observed emission ratios of VOC and NOx relative to CH4, along with available information of active wells, compressors, and processing plants. We focus on differences in meteorology, temperature, and radiation between the two winters in determining ozone concentrations in the

  14. Studies on photodegradation of two commercial dyes in aqueous phase using different photocatalysts.

    Science.gov (United States)

    Kansal, S K; Singh, M; Sud, D

    2007-03-22

    The present study involves the photocatalytic degradation of Methyl Orange (MO) and Rhodamine 6G (R6G), employing heterogeneous photocatalytic process. Photocatalytic activity of various semiconductors such as titanium dioxide (TiO(2)), zinc oxide (ZnO), stannic oxide (SnO(2)), zinc sulphide (ZnS) and cadmium sulphide (CdS) has been investigated. An attempt has been made to study the effect of process parameters viz., amount of catalyst, concentration of dye and pH on photocatalytic degradation of MO and R6G. The experiments were carried out by irradiating the aqueous solutions of dyes containing photocatalysts with UV and solar light. The rate of decolorization was estimated from residual concentration spectrophotometrically. Similar experiments were carried out by varying pH (2-10), amount of catalyst (0.25-2.0g/l) and initial concentration of dye (5-200mg/l). The experimental results indicated that the maximum decolorization (more than 90%) of dyes occurred with ZnO catalyst and at basic pH and the maximum adsorption of MO was noticed at pH 4 and of R6G at pH 10. The percentage reduction of MO and R6G was estimated under UV/solar system and it was found that COD reduction takes place at a faster rate under solar light as compared to UV light. In case of R6G, highest decolorizing efficiency was achieved with lower dose of catalyst (0.5g/l) than MO (1g/l) under similar conditions. The performance of photocatalytic system employing ZnO/solar light was observed to be better than ZnO/UV system.

  15. Studies on photodegradation of two commercial dyes in aqueous phase using different photocatalysts

    Energy Technology Data Exchange (ETDEWEB)

    Kansal, S.K. [Department of Chemical Engineering and Technology, Panjab University, Chandigarh 160014 (India)]. E-mail: sushilkk1@yahoo.co.in; Singh, M. [Department of Chemical Technology, Sant Longowal Institute of Engineering and Technology, Longowal 148106, Sangrur, Punjab (India); Sud, D. [Department of Chemistry, Sant Longowal Institute of Engineering and Technology, Longowal 148106, Sangrur, Punjab (India)

    2007-03-22

    The present study involves the photocatalytic degradation of Methyl Orange (MO) and Rhodamine 6G (R6G), employing heterogeneous photocatalytic process. Photocatalytic activity of various semiconductors such as titanium dioxide (TiO{sub 2}), zinc oxide (ZnO), stannic oxide (SnO{sub 2}), zinc sulphide (ZnS) and cadmium sulphide (CdS) has been investigated. An attempt has been made to study the effect of process parameters viz., amount of catalyst, concentration of dye and pH on photocatalytic degradation of MO and R6G. The experiments were carried out by irradiating the aqueous solutions of dyes containing photocatalysts with UV and solar light. The rate of decolorization was estimated from residual concentration spectrophotometrically. Similar experiments were carried out by varying pH (2-10), amount of catalyst (0.25-2.0 g/l) and initial concentration of dye (5-200 mg/l). The experimental results indicated that the maximum decolorization (more than 90%) of dyes occurred with ZnO catalyst and at basic pH and the maximum adsorption of MO was noticed at pH 4 and of R6G at pH 10. The percentage reduction of MO and R6G was estimated under UV/solar system and it was found that COD reduction takes place at a faster rate under solar light as compared to UV light. In case of R6G, highest decolorizing efficiency was achieved with lower dose of catalyst (0.5 g/l) than MO (1 g/l) under similar conditions. The performance of photocatalytic system employing ZnO/solar light was observed to be better than ZnO/UV system.

  16. Metabolic conversion of dicarboxylic acids to succinate in rat liver homogenates. A stable isotope tracer study.

    Science.gov (United States)

    Tserng, K Y; Jin, S J

    1991-02-15

    The metabolic conversion of dicarboxylic acids into succinate and other gluconeogenic intermediates in rat liver homogenates was investigated using [1,2,4-13C4]dodecanedioic acid as tracer. Isotope enrichments in 3-hydroxybutyrate, succinate, fumarate, and malate, as well as dicarboxylates (dodecanedioic, sebacic, suberic, and adipic acids) were measured with selected ion monitoring capillary column gas chromatograph-mass spectrometry. Significant enrichment in the M + 4 (four labeled carbons) ion of succinate (0.4-2.9%) was detected, unequivocally demonstrating the direct conversion of dicarboxylate into succinate. In addition, significant enrichment of the M + 2 ion of succinate was also observed. This labeled species was generated from labeled acetyl-CoA through the tricarboxylic acid cycle. The partition of acetyl-CoA into the tricarboxylic acid cycle relative to ketone body formation was higher in the beta oxidation of dicarboxylate than monocarboxylate. Therefore, in addition to the production of succinate, the beta oxidation of dodecanedioate resulted in the channeling of the acetyl-CoA produced to the tricarboxylic acid cycle instead of to acetoacetate production. The enrichments in lower chain dicarboxylates are consistent with a partial bidirectional beta oxidation of dodecanedioic acid. In addition to the expected M + 0 and M + 4 labels, significant M + 2 species were detected in suberic and adipic acids. These M + 2-labeled species were produced from the released free dicarboxylate intermediates which were then reactivated and metabolized. In these experiments, the overall succinate production was derived 4% from the direct conversion of dodecanedioic acid and 11% from the indirect route via acetyl-CoA through tricarboxylic acid.

  17. Tracer Study of Dentistry Graduates of one Higher Education Institution in the Philippines from 2008 to 2012

    Directory of Open Access Journals (Sweden)

    Jennifer D. Maderazo

    2016-08-01

    Full Text Available This tracer study determines the employment status of the graduates of Doctor of Dental Medicine of Lyceum of the Philippines University (LPU from 2008-2012. It assessed the relevance of the Dentistry curriculum, knowledge, skills and attitude acquired by the graduates deemed to be relevant for their employment; identify the personal and professional characteristics and job placement of Dentistry graduates and the school related factors associated with their employment. This tracer study used a descriptive research design. The study described the experiences of the graduates before and after employment. The graduates conveyed their personal observations regarding the situations they faced after graduation. The findings showed that majority of the Dentistry graduate-respondents are presently employed except for one whose primary reason is family concern and decided not to find a job. Most of the graduates had their first job as associate dentist with recommendation from the department or alumni of the college and opted to put up their own private practice after 6 months. Rewarding salaries and benefits are the main reason for staying on the job and are all enjoying a professional career in dentistry with initial gross income of 25,000 pesos and above. The following school related factors for job placement such as curriculum and instruction for the general education and professional subjects, student services and faculty instruction were found to be relevant in meeting the demands of the graduates’ dental profession. And the following are the work related values gained by the graduates such a love for God, honesty and truth, professional integrity and leadership. These values were found to be very relevant in the practice of the profession.

  18. Design and analysis of a natural-gradient ground-water tracer test in a freshwater tidal wetland, West Branch Canal Creek, Aberdeen Proving Ground, Maryland

    Science.gov (United States)

    Olsen, Lisa D.; Tenbus, Frederick J.

    2005-01-01

    A natural-gradient ground-water tracer test was designed and conducted in a tidal freshwater wetland at West Branch Canal Creek, Aberdeen Proving Ground, Maryland. The objectives of the test were to characterize solute transport at the site, obtain data to more accurately determine the ground-water velocity in the upper wetland sediments, and to compare a conservative, ionic tracer (bromide) to a volatile tracer (sulfur hexafluoride) to ascertain whether volatilization could be an important process in attenuating volatile organic compounds in the ground water. The tracer test was conducted within the upper peat unit of a layer of wetland sediments that also includes a lower clayey unit; the combined layer overlies an aquifer. The area selected for the test was thought to have an above-average rate of ground-water discharge based on ground-water head distributions and near-surface detections of volatile organic compounds measured in previous studies. Because ground-water velocities in the wetland sediments were expected to be slow compared to the underlying aquifer, the test was designed to be conducted on a small scale. Ninety-seven ?-inch-diameter inverted-screen stainless-steel piezometers were installed in a cylindrical array within approximately 25 cubic feet (2.3 cubic meters) of wetland sediments, in an area with a vertically upward hydraulic gradient. Fluorescein dye was used to qualitatively evaluate the hydrologic integrity of the tracer array before the start of the tracer test, including verifying the absence of hydraulic short-circuiting due to nonnatural vertical conduits potentially created during piezometer installation. Bromide and sulfur hexafluoride tracers (0.139 liter of solution containing 100,000 milligrams per liter of bromide ion and 23.3 milligrams per liter of sulfur hexafluoride) were co-injected and monitored to generate a dataset that could be used to evaluate solute transport in three dimensions. Piezometers were sampled 2 to 15 times

  19. Copper Ion as a New Leakage Tracer

    Directory of Open Access Journals (Sweden)

    Modaresi J.

    2013-12-01

    Full Text Available Statement of Problem: Most failures of root canal treatments are caused by bacteria. Studies showed that the most common cause of endodontic failures were the incomplete obturation of the root canal and the lack of adequate apical seal. Some in-vitro methods are used to estimate sealing quality, generally by measuring microleakage that allows the tracer agent to penetrate the filled canal.Purpose: Conventional methods of evaluating the seal of endodontically treated teeth are complicated and have some drawbacks. We used copper ion diffusion method to assess the leakage and the results were compared to dye penetration method.Materials and Method: The crowns of 21 extracted teeth were cut off at the CEJ level. After preparing the canals, the teeth were placed in tubes containing saline. They were divided randomly into 15 experimental cases; 3 positive and 3 negative controls. Positive controls were filled by single cone without sealer while the experimental and the negative control groups were filled by lateral technique. The coronal portion of gutta was removed and 9mm was left. The external surface of each tooth was coated with nail polish. Two millimeters of apical portion was immersed into 9ml of distilled water and 0.3ml of CuSO4 solution was injected into the coronal portion. After 2 days, copper sulfate was measured by an atomic absorption spectrophotometer. The teeth were then immersed in 2% methylene blue for 24 hours, sectioned and the extent of dye penetration was measured by a stereomicroscope.Results: The maximum and minimum recorded copper ion concentrations for the experimental group were 18.37 and 2.87ppm respectively. The maximum and minimum recorded dye penetrations for the experimental group were 8.5 and 3.5mm respectively. The statistical analysis, adopting paired samples test, showed poor correlation between average recorded results of two methods.Conclusion: Based on our results, there was no significant correlation between

  20. Heat tracer test in an alluvial aquifer: field experiment and inverse modelling

    Science.gov (United States)

    Klepikova, Maria; Wildemeersch, Samuel; Jamin, Pierre; Orban, Philippe; Hermans, Thomas; Nguyen, Frederic; Brouyère, Serge; Dassargues, Alain

    2016-04-01

    Using heat as an active tracer for aquifer characterization is a topic of increasing interest. In this study, we investigate the potential of using heat tracer tests for characterization of a shallow alluvial aquifer. A thermal tracer test was conducted in the alluvial aquifer of the Meuse River, Belgium. The tracing experiment consisted in simultaneously injecting heated water and a dye tracer in a piezometer and monitoring the evolution of groundwater temperature and tracer concentration in the recovery well and in monitoring wells. To get insights in the 3D characteristics of the heat transport mechanisms, temperature data from a large number of observation wells distributed throughout the field site (space-filling arrangement) were used. Temperature breakthrough curves in observation wells are contrasted with what would be expected in an ideal layered aquifer. They reveal strongly unequal lateral and vertical components of the transport mechanisms. The observed complex behavior of the heat plume was explained by the groundwater flow gradient on the site and heterogeneity of hydraulic conductivity field. Moreover, due to high injection temperatures during the field experiment a temperature-induced fluid density effect on heat transport occurred. By using a flow and heat transport numerical model with variable density coupled with the pilot point inverse approach, main preferential flow paths were delineated.

  1. Strategies for modulating the luminescence properties of pyronin Y dye-clay films: an experimental and theoretical study.

    Science.gov (United States)

    Epelde-Elezcano, Nerea; Martínez-Martínez, Virginia; Duque-Redondo, Eduardo; Temiño, Inés; Manzano, Hegoi; López-Arbeloa, Iñigo

    2016-03-28

    The aggregation process, particularly the type and extent of pyronin Y (PY) laser dye intercalated into supported thin films of two different trioctahedral clay minerals, LAPONITE® (Lap) and saponite (Sap), at different dye loadings is studied: (i) experimentally by means of electronic absorption and fluorescence spectroscopy and (ii) theoretically by modeling the distribution of the dye into the interlayer space of these layered silicates. According to the results, H-type aggregates of the PY dye are favoured in Lap even at very low dye loading while a much lower molecular aggregation tendency in J-type geometry is found in Sap films. The aggregation state of PY in each clay mineral is likely attributed to different strengths of the electrostatic interactions between the dye and the layered silicate in the interlayer space due to their distinctive charge localization on the TOT clay layer (i.e. net negative charge in octahedral layers for Lap vs. in tetrahedral layers for Sap), as well as the interlaminar water distribution in each clay mineral, although other factors such as their CEC and particle size cannot be discarded. To reduce the huge aggregation processes of PY dye into Lap films, surfactant molecules (DDTAB) are co-adsorbed in the interlayer space of the clay. At an optimized surfactant concentration, the aggregation tendency of PY dye in Lap is considerably reduced enormously improving the fluorescence efficiency of the PY/Lap films. Finally, by means of anisotropic response from the hybrid films to the plane of the polarized light, the orientation of the PY molecules with respect to the normal axis of the clay layer is determined for all films (with and without surfactant) at different dye loadings.

  2. Bengal gram seed husk as an adsorbent for the removal of dyes from aqueous solutions – Equilibrium studies

    Directory of Open Access Journals (Sweden)

    M.C. Somasekhara Reddy

    2017-05-01

    Full Text Available Seed husk of Bengal gram (SHBG (Scientific Name: Cicer arietinum was used as an adsorbent for the removal of a direct dye namely Congo red (CR, two basic dyes namely methylene blue (MB & rhodamine-B (RB and an acidic dye namely acid blue 25 (AB from aqueous solutions with equilibrium isotherms. The effect of particle size, of mass of adsorbent, of agitation speed of shaker and of temperature of dye solutions was studied for understanding the interaction of dyes with adsorbent. The uptake of dyes by the adsorbent was increasing with increasing mass of the adsorbent, decreasing with increasing size of the adsorbent, and increasing with increasing agitation speed and temperature. The adsorption capacity for each dye-adsorbent system was determined by using the Langmuir isotherm. The adsorption capacity of adsorbent for MB, RB, CR and AB was 333.33, 133.34, 78.12 and 5.56 mg g−1, respectively. The experimental data fit well with the Langmuir and Freundlich models. The standard enthalpy change of adsorption for MB, RB, CR and AB was 13.5, 10.97, 4.01 and 6.72 kJ mol−1, respectively. The average standard entropy change of adsorption for MB, RB, CR and AB is 58.2957, 36.869, 13.2138 and −3.4179 kJ mol−1, respectively. The adsorption of two basic dyes is much higher than that of the direct and acid dyes.

  3. Dyeing of Polypropylene Fibers with Vat Dyes

    Institute of Scientific and Technical Information of China (English)

    LIU Hang; ETTERS J. Nolan; LEONAS Karen K

    2006-01-01

    Polypropylene fibers have been extensively used in a variety of products, including carpets and upholstery, due to their non-absorbency, good weather resistance, good resistance to microorganisms and so on. Because of their hydrophobic and highly crystalline nature, those well-established conventional dyeing processes are difficult to apply to unmodified polypropylene. Colors of polypropylene fibers are primarily obtained by mass coloration which has the disadvantages of limited number of colors available and difficulties in inventory control due to the rapidly changing color needs of the market. In this paper, the use of vat dyes to dye polypropylene fabrics is investigated. Seventeen vat dyes were screened and factors influencing uptake of dyes by polypropylene fabrics were studied.

  4. sup 26 Al tracer experiment by accelerator mass spectrometry and its application to the studies for amyotrophic lateral sclerosis and Alzheimer's disease, 1

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Koichi (Tokyo Univ. (Japan). Research Center for Nuclear Science and Technology); Yumoto, Sakae; Nagai, Hisao; Hosoyama, Yoshiyuki; Imamura, Mineo; Masuzawa, Shin-ichirou; Koizumi, Yoshinobu; Yamashita, Hiroshi

    1990-12-01

    Accelerator mass spectrometry (AMS) was applied for {sup 26}Al tracer experiment to study the aluminum toxicity and metabolism in rats. To investigate the cause of amyotrophic lateral sclerosis (ALS) and Alzheimer's disease, the aluminum incorporation into the brain (cerebrum) was studied by AMS using {sup 26}Al as a tracer. When {sup 26}Al was intraperitoneally injected into rats, a considerable amount of {sup 26}Al was incorporated into the cerebrum after 5-35 days of the injection. (author).

  5. O-18 tracer studies of Al2O3 scale formation on NiCrAl alloys

    Science.gov (United States)

    Reddy, K. P. R.; Cooper, A. R.; Smialek, J. L.

    1982-01-01

    Diffusion processes in Al2O3 scales formed on NiCrAl + Zr alloys were studied by the proton activation technique employing the O-18 isotope as a tracer. The O-18 profiles identified a zone of oxide penetration beneath the external scale. Both this subscale formation and the outer Al2O3 scale thickness were shown by this technique to increase with Zr content in the alloy. Estimated kp's from scale thicknesses were in agreement with gravimetric measurements for various Zr levels. Alternate exposures in O-16 and O-18 revealed that oxygen inward transport was the primary growth mechanism. A qualitative analysis of these O-18 profiles indicated that the oxygen transport was primarily via short-circuit paths, such as grain boundaries.

  6. Development of sustainable dye adsorption system using Nutraceutical Industrial Fennel Seed Spent - Studies with Congo Red dye.

    Science.gov (United States)

    Taqui, Syed Noeman; Yahya, Rosiyah; Hassan, Aziz; Nayak, Nayan; Syed, Akheel Ahmed

    2017-01-25

    Fennel seed spent (FSS) - an inexpensive nutraceutical industrial spent has been used as an efficient biosorbent for the removal of Congo Red (CR) from aqueous media. Results show that pH of 2 - 4 and temperature of 30°C was ideal for maximum adsorption. Based on regression fitting of the data it was determined that the SIPS isotherm (R(2) = 0.994, χ(2) = 0.5) adequately described the mechanism of adsorption, suggesting that the adsorption occurs in a homogeneous layer by layer with favourable interaction between layers. Thermodynamic analysis showed that the adsorption is favourable (negative values for ΔG°) and endothermic (ΔH° = 12-20 kJ mol(-1)) for an initial dye concentration of 25, 50 and 100 ppm. The low ΔH° value indicates that the adsorption is a physical process involving weak chemical interactions like hydrogen bonds and van der Waals interactions. The kinetics revealed that the adsorption process showed pseudo second order tendencies with the equal influence of intra-particle as well as film diffusion. The SEM images of FSS show a highly fibrous matrix with a hierarchical porous structure. The FTIR analysis of the spent confirmed the presence of cellulosic and ligno-cellulosic matter giving it both hydrophilic and hydrophobic properties. The investigations indicate that FSS is a cost-effective and efficient biosorbent for the remediation of toxic Congo Red dye.

  7. On the use of flow-storage repartitions derived from artificial tracer tests for geothermal reservoir characterization in the Malm-Molasse basin: a theoretical study

    Science.gov (United States)

    Dewi, Dina Silvia; Osaigbovo Enomayo, Augustine; Mohsin, Rizwan; Karmakar, Shyamal; Ghergut, Julia; Sauter, Martin

    2016-04-01

    needed to calculate FSR. Looking at the Sauerlach example, we find that premature interruption of tracer sampling systematically leads to overestimating the reservoir's storage capacity and underestimating its flow capacity, with misestimation generally increasing as the bedded/reef interfacial area per volume is increased. It is interesting to correlate these findings with the tracer-based approach to facies identification for the shallower Malm aquifers of the Southern Franconian Alb, proposed by Seiler et al. (1989, 1995) and with expectations from the direct (i. e., distributed-parameter) modeling of matrix-diffusive effects (Maloszewski and Zuber 1985) on measured tracer signals. References: Maloszewski P, Zuber A (1985) On the theory of tracer experiments in fissured rocks with a porous matrix, Journal of Hydrology, 79, 333-358 Seiler K-P, Behrens H, Wolf M (1995) Use of artificial and environmental tracers to study storage and drainage of groundwater in the Franconian Alb, Germany, and the consequences for groundwater protection, Proc Isotopes in Water Resources Management, 2, 135-146 (IAEA, Vienna) Seiler K-P, Maloszewski P, Behrens H (1989) Hydrodynamic dispersion in karstified limestones and dolomites in the Upper Jurassic of the Franconian Alb, FRG, Journal of Hydrology, 108, 235-247 Shook G M (2003) A Simple, Fast Method of Estimating Fractured Reservoir Geometry from Tracer Tests, Geothermal Resources Council Transactions, 27, 407-411 Financial support from the German Federal Ministry for Economic Affairs and Energy is gratefully acknowledged. - Gefördert durch BMWi aufgrund eines Beschlusses des Deutschen Bundestages (FKZ 0325515 "TRENDS").

  8. A Study on RR4 Dye as a Sensitizer in Enhancing Photoactivity of Immobilized Photocatalysts

    Directory of Open Access Journals (Sweden)

    Bakar F.

    2016-01-01

    Full Text Available In this work, anionic RR4 dye was used to sensitize TiO2/PVA and TiO2/PEG immobilized system in enhancing photocatalytic degradation of cationic methylene blue (MB dye. 0.3g of TiO2 and polymer binder was coated onto a clean glass plate by using brush technique to develop optimum immobilize TiO2 system. A comparison study between immobilized TiO2/PVA (Im/TiO2/PVA and Immobilized TiO2/PEG (Im/TiO2/PEG system with and without RR4 sensitizer were carried out under 45 W fluorescent lamp and visible light irradiation. The photocatalytic degradation of MB was significantly enhanced for both RR4 dye sensitized Im/TiO2/PVA and Im/TiO2/PEG with 1st order rate constant was ca. 0.035 and 0.030 min-1 respectively under 45-W fluorescent lamp. Same observation as well under visible light irradiation whereby enhanced of those RR4 sensitized immobilized photocatalysts were recorded as compared with immobilized photocatalysts without RR4 as sensitizer. The photocatalytic enhancement under Im/TiO2/PVA/RR4 and Im/TiO2/PEG/RR4 are due to the ability of RR4 dye to become electron (e- donor for conduction band (CB of TiO2, thus making TiO2 CB riches with electron, eventually this e- is used to remove MB by producing hydroxyl radical.

  9. Performance of SBR for the treatment of textile dye wastewater: Optimization and kinetic studies

    Directory of Open Access Journals (Sweden)

    S. Sathian

    2014-06-01

    Full Text Available In this work, sequential batch reactor (SBR was employed for the treatment of textile dye wastewater. The performance of four white rot fungi (WRF viz. Coriolus versicolor, Pleurotus floridanus, Ganoderma lucidum and Trametes pubescens was evaluated in pure and mixed combinations in terms of decolorization. From the results it was found that the combination of Pleurotus floridanus, Ganoderma lucidum and Trametes pubescens was best and they were used in the SBR. The process parameters like air flow rate, sludge retention time (SRT and cycle period were optimized using response surface methodology (RSM. At these optimized conditions, treatment of textile dye wastewater was carried out at various initial dye wastewater concentration and hydraulic retention time. The performance of SBR was analyzed in terms of decolorization, COD reduction and sludge volume index (SVI. From the results it was found that a maximum decolorization and COD reduction of 71.3% and 79.4%, respectively, was achieved in the SBR at an organic loading rate of 0.165 KgCOD/m3 d. The sludge volume index (SVI was found to be low in the range of 90–103 mL/g. The kinetic study was carried out using a first order based model and the degradation follows the first order system.

  10. DBD dyes as fluorescence lifetime probes to study conformational changes in proteins.

    Science.gov (United States)

    Wawrzinek, Robert; Ziomkowska, Joanna; Heuveling, Johanna; Mertens, Monique; Herrmann, Andreas; Schneider, Erwin; Wessig, Pablo

    2013-12-16

    Previously, [1,3]dioxolo[4,5-f][1,3]benzodioxole (DBD)-based fluorophores used as highly sensitive fluorescence lifetime probes reporting on their microenvironmental polarity have been described. Now, a new generation of DBD dyes has been developed. Although they are still sensitive to polarity, in contrast to the former DBD dyes, they have extraordinary spectroscopic properties even in aqueous surroundings. They are characterized by long fluorescence lifetimes (10-20 ns), large Stokes shifts (≈100 nm), high photostabilities, and high quantum yields (>0.56). Here, the spectroscopic properties and synthesis of functionalized derivatives for labeling biological targets are described. Furthermore, thio-reactive maleimido derivatives of both DBD generations show strong intramolecular fluorescence quenching. This mechanism has been investigated and is found to undergo a photoelectron transfer (PET) process. After reaction with a thiol group, this fluorescence quenching is prevented, indicating successful bonding. Being sensitive to their environmental polarity, these compounds have been used as powerful fluorescence lifetime probes for the investigation of conformational changes in the maltose ATP-binding cassette transporter through fluorescence lifetime spectroscopy. The differing tendencies of the fluorescence lifetime change for both DBD dye generations promote their combination as a powerful toolkit for studying microenvironments in proteins.

  11. Textile dye removal from aqueous solutions by malt bagasse: Isotherm, kinetic and thermodynamic studies.

    Science.gov (United States)

    Fontana, Klaiani B; Chaves, Eduardo S; Sanchez, Jefferson D S; Watanabe, Erica R L R; Pietrobelli, Juliana M T A; Lenzi, Giane G

    2016-02-01

    The biosorption of orange solimax TGL 182% (OS-TGL) textile dye onto new and low cost biossorbent (malt bagasse) in aqueous solutions was investigated. The malt bagasse was characterized by Fourier transform infrared spectroscopy and specific surface area (BET method).Batch biosorption experiments were conducted in order to determine the following parameters: particles size, pH, agitation speed, temperature, contact time, biomass dosage, influence of the ionic strength and, finally, the influence of other textile dye on the OS-TGL biosorption. The optimum conditions for OS-TGL removal were obtained at pH 1.5, agitation speed of 150rpm, contact time of 180min and biomass dosage 2, 8gL(-1). The results show that the kinetics of biosorption followed a pseudo-second-order model and by increasing the temperature from 293 up to 313K, the biosorption capacity was improved. The Langmuir model showed better fit and the estimated biosorption capacity was 23.2mgg(-1). The negative values of Gibbs free energy, ΔG°, and positive value of enthalpy, ΔH°, confirm the spontaneous nature and endothermic character of the biosorption process. The results of the ionic strength effect indicated that the biosorption process under study had a strong tolerance in high salt concentrations. The removal capacity (>95%) was not affected with the presence of other textile dyes.

  12. Experimental and kinetic studies for phycoremediation and dye removal by Chlorella pyrenoidosa from textile wastewater.

    Science.gov (United States)

    Pathak, Vinayak V; Kothari, Richa; Chopra, A K; Singh, D P

    2015-11-01

    Potential of Chlorella pyrenoidosa was experimentally investigated for phycoremediation and dye removal from textile wastewater (TWW) in batch cultures. Growth of alga was observed at various concentration of textile wastewater (25%, 50%, 75% and 100%) and was found in a range of 8.1-14 μg ml(-1) day(-1). Growth study revealed that alga potentially grows up to 75% concentrated textile wastewater and reduces phosphate, nitrate and BOD by 87%, 82% and 63% respectively. Methylene blue dye (MB) removal was also observed by using dry and wet algal biomass harvested after phycoremediation. Adsorption isotherms (Langmuir and Freundlich) and kinetic models (pseudo first and second order) were applied on adsorption process. Dry algal biomass (DAB) was found more efficient biosorbent with large surface area and showed high binding affinity for MB dye in compare to wet algal biomass (WAB). The RL value for both biosorbent showed feasible adsorption process as the obtained value was between 0 and 1. Pseudo second order kinetic model with high degree of correlation coefficient and low sum of error squares (SSE %) value was found more suitable for representation of adsorption process in case of both biosorbents, however pseudo first order also showed high degree of correlation for both biosorbents.

  13. The Transient Tracers in the Ocean (TTO) program: The North Atlantic Study, 1981; The Tropical Atlantic Study, 1983

    Science.gov (United States)

    Brewer, Peter G.; Sarmiento, Jorge L.; Smethie, William M.

    1985-01-01

    The scientific papers here collected result from the Transient Tracers in the Ocean (TTO) program. The two parts of this major geochemical and physical oceanographie expedition took place in the North Atlantic Ocean in 1981 and in the Tropical Atlantic in 1983 on the research vessel Knorr of the Woods Hole Oceanographie Institution. The expeditions, sponsored by the National Science Foundation and the U.S. Department of Energy (North Atlantic only), were designed to observe the passage of man-made geochemical tracers into the interior of the ocean. The foundations for such an experiment were laid in the 1972-1978 GEOSECS program. Here, for the first time, a systematic survey revealed the penetration into the thermocline and deep ocean of the products of man's military/industrial activities, principally tritium and carbon-14 resulting from atmospheric testing of nuclear weapons, which terminated with the nuclear test ban treaty in 1962.

  14. Preparation of mono-radioiodinated tracers for study of the in vivo metabolism of atrial natriuretic peptide in humans

    Energy Technology Data Exchange (ETDEWEB)

    Clerico, A. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Iervasi, G. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Manfredi, C. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Salvadori, S. [Dept. of Pharmaceutical Sciences, Univ. of Ferrara (Italy); Marastoni, M. [Dept. of Pharmaceutical Sciences, Univ. of Ferrara (Italy); Del Chicca, M.G. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Giannessi, D. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Del Ry, S. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Andreassi, M.G. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Sabatino, L. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Iascone, M.R. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Biagini, A. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica; Donato, L. [Consiglio Nazionale delle Ricerche, Pisa (Italy). Lab. di Fisiologia Clinica

    1995-09-01

    The authors evaluate the optimum chemical conditions for labelling atrial natriuretic peptide (ANP) and its metabolites and for preparing highly purified radiotracers which can be used for in vivo kinetic studies of ANP in humans. Synthetic {alpha} h{sub 1-28}ANP and some hormone metabolites were iodinated with Na{sup 125}I or Na{sup 131}I by means of the lactoperoxidase (ANP) or the chloramine-T (ANP metabolites) technique. The biological activity of labelled ANP was tested by means of a binding study using mouse cardiac membranes. A high-performance liquid chromatography (HPLC) procedure was used to purify the labelled hormone and the principal labelled metabolites in venous plasma samples collected up to 50 min after the injection of {sup 125}I-labelled ANP from nine healthy men. The main ANP kinetic parameters were derived from the disappearance curves of the [{sup 125}I]ANP, which were satisfactorily fitted by a bi-exponential function in all subjects. The main advantages of this tracer technique are high accuracy, allowing the identification of the metabolites produced in vivo under steady-state conditions after injection of the precursor (labelled hormone) high sensitivity, allowing the detection of minimal quantities of metabolites high specificity, allowing the detection of possible in vitro artefactual generation of cleavage products of ANP using an internal labelled standard. Utilizing this tracer method, it was possible to estimate the principal parameters of ANP kinetics and also to plot the appearance curves of the labelled metabolites produced in vivo after the injection of the labelled precursor. (orig.). With 5 figs.

  15. Interaction of phenazinium dyes with double-stranded poly(A): spectroscopy and isothermal titration calorimetry studies.

    Science.gov (United States)

    Khan, Asma Yasmeen; Saha, Baishakhi; Kumar, Gopinatha Suresh

    2014-10-15

    A comprehensive study on the binding of phenazinium dyes viz. janus green B, indoine blue, safranine O and phenosafranine with double stranded poly(A) using various spectroscopic and calorimetric techniques is presented. A higher binding of janus green B and indoine blue over safranine O and phenosafranine to poly(A) was observed from all experiments. Intercalative mode of binding of the dyes was inferred from fluorescence polarization anisotropy, iodide quenching and viscosity experiments. Circular dichroism study revealed significant perturbation of the secondary structure of poly(A) on binding of these dyes. Results from isothermal titration calorimetry experiments suggested that the binding was predominantly entropy driven with a minor contribution of enthalpy to the standard molar Gibbs energy. The results presented here may open new opportunities in the application of these dyes as RNA targeted therapeutic agents.

  16. [Tattooing dyes].

    Science.gov (United States)

    Lehmann, G; Pierchalla, P

    1988-01-01

    Nine different tattoo dyes were analysed by various tests. Mixtures of organic dyes and inorganic filler were found; the inorganic filler consisted mainly of titanium dioxide (TiO2). Heavy metals, e.g. mercury, cadmium, or chrome as the common components of the traditional tattoo dyes, are capable of evoking unwanted skin reactions, but were not detected. Tattoo dyes are not officially controlled, and thus it is not known which substances-in addition to those identified by us-are presently used to produce ornamental tattoos. However, our results suggest that classic dyes have been superceded by newer, mainly synthetic dyes.

  17. 亚甲蓝示踪乳腺癌效果的研究%The Study of Effects on Methylene Blue as Breast Cancer Tracer

    Institute of Scientific and Technical Information of China (English)

    周国庆; 郑冬梅; 崔保国; 张曼丽; 兰涛

    2013-01-01

      目的:亚甲蓝示踪乳腺癌效果的评价.方法:将术前确诊乳腺癌的患者进行乳腺癌组织及其周围注射亚甲蓝,术中进行腋窝淋巴结清扫时,将染色与非染色淋巴结进行分类,并标明各淋巴结的所在组别.结合病理区分淋巴结转移的真阴性、假阴性、真阳性、假阳性.以此作为乳腺癌示踪技术的成功与否的依据.结果:63例检出的前哨淋巴结中,阴性26例,阳性37例,阳性率58.73%.65例腋窝淋巴结阳性38例,阳性率58.46%.SLN与ALN经病理检查完全符合者36例.2例前哨淋巴结阴性而腋窝淋巴结阳性,1例前哨淋巴结阳性而腋窝淋巴结阴性.前哨淋巴结活检技术的评价:灵敏度(SLN阳性数37/腋窝淋巴结转移数38)97.3%,准确度(SLN真阳性与真阴性的数之和60/S L N活检总数63)为95.2%,假阳性率(SLN假阳性的例数1/腋窝淋巴结转移例数38)2.6%,假阴性率(SLN假阴性的例数2/腋窝淋巴结转移例数38)5.2%.结论:使用染料亚甲蓝示踪乳腺癌前哨淋巴结活检,准确掌握适应症、示踪条件后,检出的淋巴结敏感性和准确性均较高,临床应用简便,安全性高,能较准确地预测腋窝淋巴结转移的情况.%Objective:The study of the effects of methylene blue tracer breast cancer.Methods:The preoperative diagnosis of breast cancer patients with breast cancer tissue and its surrounding injection of methylene blue, surgery for axillary lymph node dissection, staining and non-staining lymph node classification, and indicate where each lymph node group. Combined with pathological distinction between lymph node metastasis of true negative, false negative, true positive, false positive. As a basis for breast cancer tracer technique the success.Results:63 cases detected in the sentinel lymph node negative in 26 cases, 37 cases positive, the positive rate of 58.73%. 65 cases of axillary lymph node was positive in 38 cases, the positive rate of 58.46%. SLN and ALN

  18. Heat tracer test in an alluvial aquifer: Field experiment and inverse modelling

    Science.gov (United States)

    Klepikova, Maria; Wildemeersch, Samuel; Hermans, Thomas; Jamin, Pierre; Orban, Philippe; Nguyen, Frédéric; Brouyère, Serge; Dassargues, Alain

    2016-09-01

    Using heat as an active tracer for aquifer characterization is a topic of increasing interest. In this study, we investigate the potential of using heat tracer tests for characterization of a shallow alluvial aquifer. A thermal tracer test was conducted in the alluvial aquifer of the Meuse River, Belgium. The tracing experiment consisted in simultaneously injecting heated water and a dye tracer in an injection well and monitoring the evolution of groundwater temperature and tracer concentration in the pumping well and in measurement intervals. To get insights in the 3D characteristics of the heat transport mechanisms, temperature data from a large number of observation wells closely spaced along three transects were used. Temperature breakthrough curves in observation wells are contrasted with what would be expected in an ideal layered aquifer. They reveal strongly unequal lateral and vertical components of the transport mechanisms. The observed complex behavior of the heat plume is explained by the groundwater flow gradient on the site and heterogeneities in the hydraulic conductivity field. Moreover, due to high injection temperatures during the field experiment a temperature-induced fluid density effect on heat transport occurred. By using a flow and heat transport numerical model with variable density coupled with a pilot point approach for inversion of the hydraulic conductivity field, the main preferential flow paths were delineated. The successful application of a field heat tracer test at this site suggests that heat tracer tests is a promising approach to image hydraulic conductivity field. This methodology could be applied in aquifer thermal energy storage (ATES) projects for assessing future efficiency that is strongly linked to the hydraulic conductivity variability in the considered aquifer.

  19. Thermodynamic Study of the Ion-Pair Complexation Equilibria of Dye and Surfactant by Spectral Titration and Chemometric Analysis

    Directory of Open Access Journals (Sweden)

    Hakimeh Abbasi Awal

    2017-12-01

    Full Text Available Surfactant-dye interactions are very important in chemical and dyeing processes. The dyes interact strongly with surfactant and show new spectrophotometric properties, so the UV-vis absorption spectrophotometric method has been used to study this process and extract some thermodynamic parameters. In this work, the association equilibrium between ionic dyes and ionic surfactant were studied by analyzing spectrophotometric data using chemometric methods. Methyl orange and crystal violet were selected as a model of cationic and anionic dyes respectively. Also sodium dodecyl sulphate and cetyltrimethylammonium bromide were selected as anionic and cationic surfactant, respectively. Hard model methods such as target transform fitting (TTF classical multi-wavelength fitting and soft model method such as multivariate curve resolution (MCR were used to analyze data that were recorded as a function of surfactant concentration in premicellar and postmicellar regions. Hard model methods were used to resolve data using ion-pair model in premicellar region in order to extract the concentration and spectral profiles of individual components and also related thermodynamic parameters. The equilibrium constants and other thermodynamic parameters of interaction of dyes with surfactants were determined by studying the dependence of their absorption spectra on the temperature in the range 293–308 K at concentrations of 5 × 10−6 M and 8 × 10−6 M for dye crystal violet and methyl orange, respectively. In postmicellar region, the MCR-ALS method was applied for resolving data and getting the spectra and concentration profiles in complex mixtures of dyes and surfactants.

  20. Study of the sonophotocatalytic degradation of basic blue 9 industrial textile dye over slurry titanium dioxide and influencing factors.

    Science.gov (United States)

    González, Antonia Sandoval; Martínez, Susana Silva

    2008-09-01

    The sonophotocatalytic degradation of basic blue 9 industrial textile dye has been studied in the presence of ultrasound (20 kHz) over a TiO(2) slurry employing an UV lamp (15 W, 352 nm). It was observed that the color removal efficiency was influenced by the pH of the solution, initial dye concentration and TiO(2) amount. It was found that the dye degradation followed apparent first order kinetics. The rate constant increased by decreasing dye concentration and was affected by the pH of the solution with the highest degradation obtained at pH 7. The first order rate constants obtained with sonophotocatalysis were twofold and tenfold than those obtained under photocatalysis and sonolysis, respectively. The chemical oxygen demand was abated over 80%.

  1. Biosorption of six basic and acidic dyes on brown alga Sargassum ilicifolium: optimization, kinetic and isotherm studies.

    Science.gov (United States)

    Tabaraki, Reza; Sadeghinejad, Negar

    2017-06-01

    Biosorption of Methyl Blue (MB), Fuchsin Acid (FA), Rhodamine B (RB), Methylene Blue (MEB), Bromocresol purple (BC) and Methyl Orange (MO) onto Sargassum ilicifolium was studied in a batch system. Effect of dye structure on biosorption by Sargassum ilicifolium was studied to define the correlation between chemical structure and biosorption capacity. Different dye groups such as triarylmethane (MB, FA and BC), monoazo (MO), thiazine (MEB) and xanthene (RB) were studied. At optimum experimental conditions for each dye, biosorption capacity was determined and compared. The results indicate that the chemical structure (triarylmethane, monoazo, thiazine, xanthene), number of sulfonic groups, basicity (element of chromophore group: S, N, O) and molecular weight of dye molecules influence their biosorption capacity. Experimental parameters such as biosorbent dose, pH, contact time, and initial dye concentration were optimized for each dye. The biosorption kinetic data were successfully described by the pseudo second-order model. The biosorption results were also analyzed by the Langmuir and Freundlich isotherms. Finally, biosorption capacities obtained using Sargassum ilicifolium were compared with the ones presented in the literature.

  2. Experimental and Computational Studies on the Design of Dyes for Water-splitting Dye-sensitized Photoelectrochemical Tandem Cells

    Science.gov (United States)

    Mendez-Hernandez, Dalvin D.

    Solar energy is a promising alternative for addressing the world's current and future energy requirements in a sustainable way. Because solar irradiation is intermittent, it is necessary to store this energy in the form of a fuel so it can be used when required. The light-driven splitting of water into oxygen and hydrogen (a useful chemical fuel) is a fascinating theoretical and experimental challenge that is worth pursuing because the advance of the knowledge that it implies and the availability of water and sunlight. Inspired by natural photosynthesis and building on previous work from our laboratory, this dissertation focuses on the development of water-splitting dye-sensitized photoelectrochemical tandem cells (WSDSPETCs). The design, synthesis, and characterization of high-potential porphyrins and metal-free phthalocyanines with phosphonic anchoring groups are reported. Photocurrents measured for WSDSPETCs made with some of these dyes co-adsorbed with molecular or colloidal catalysts on TiO2 electrodes are reported as well. To guide in the design of new molecules we have used computational quantum chemistry extensively. Linear correlations between calculated frontier molecular orbital energies and redox potentials were built and tested at multiple levels of theory (from semi-empirical methods to density functional theory). Strong correlations (with r2 values > 0.99) with very good predictive abilities (rmsd reaction center of Photosystem II. It was found that the inclusion of explicit solvent molecules, hydrogen bonded to specific sites within the molecular triad, was essential to explain the observed thermal relaxation. These results are relevant for both advancing the knowledge about natural photosynthesis and for the future design of new molecules for WSDSPETCs.

  3. Tracer tests in geothermal resource management

    OpenAIRE

    Axelsson G.

    2013-01-01

    Geothermal reinjection involves injecting energy-depleted fluid back into geothermal systems, providing an effective mode of waste-water disposal as well as supplementary fluid recharge. Cooling of production boreholes is one of the main disadvantages associated with reinjection, however. Tracer testing is an important tool for reinjection studies because tracer tests actually have a predictive power since tracer transport is orders of magnitude faster than cold-front advancement around reinj...

  4. Biochemical activity of a fluorescent dye rhodamine 6G: Molecular modeling, electrochemical, spectroscopic and thermodynamic studies.

    Science.gov (United States)

    Al Masum, Abdulla; Chakraborty, Maharudra; Ghosh, Soumen; Laha, Dipranjan; Karmakar, Parimal; Islam, Md Maidul; Mukhopadhyay, Subrata

    2016-11-01

    Interaction of CT DNA with Rhodamine 6G (R6G) has been studied using molecular docking, electrochemical, spectroscopic and thermodynamic methods. From the study, it was illustrated that Rhodamine 6G binds to the minor groove of CT DNA. The binding was cooperative in nature. Circular voltametric study showed significant change in peak current and peak potential due to complexation. All the studies showed that the binding constant was in the order of 10(6)M(-1). Circular dichroic spectra showed significant conformational change on binding and DNA unwind during binding. Thermodynamic study showed that binding was favored by negative enthalpy and positive entropy change. From thermodynamic study it was also observed that several positive and negative free energies played significant role during binding and the unfavorable conformational free energy change was overcame by highly negative hydrophobic and salt dependent free energy changes. The experimental results were further validated using molecular docking study and the effect of structure on binding has been studied theoretically. From docking study it was found that the hydrophobic interaction and hydrogen bonds played a significant role during binding. The dye was absorbed by cell and this phenomenon was studied using fluorescent microscope. Cell survivability test showed that the dye active against Human Breast Cancer cells MDA-MB 468. ROS study showed that the activity is due to the production of reactive oxygen.

  5. Patch testing with a textile dye mix – a multicentre study

    DEFF Research Database (Denmark)

    Ryberg, Kristina; Agner, Tove; Andersen, Klaus E;

    2014-01-01

    BACKGROUND: Disperse dyes are well-known contact sensitizers. However, they are not included in the majority of commercially available baseline patch test series. OBJECTIVES: To investigate the outcome of patch testing with a textile dye mix (TDM) consisting of eight disperse dyes at dermatology ...

  6. Ab initio study of energy-level alignments in polymer-dye blends

    NARCIS (Netherlands)

    Pasveer, W.F.; Bobbert, P.A.; Michels, M.A.J.; Langeveld-Voss, B.M.W.; Schoo, H.F.M.; Bastiaansen, J.J.A.M.

    2003-01-01

    Polymers with a small amount of dye blended in offer an attractive possibility to change the color of the emitted light by changing the dye. We present ab initio calculations within density-functional theory of the HOMO/ LUMO energies for dipyrrolomethane dyes, polyphenylenevinylene and polyfluorene

  7. Ab initio study of energy-level alignments in polymer-dye blends

    NARCIS (Netherlands)

    Pasveer, W.F.; Bobbert, P.A.; Michels, M.A.J.; Langeveld-Voss, B.M.W.; Schoo, H.F.M.; Bastiaansen, J.J.A.M.

    2003-01-01

    Polymers with a small amount of dye blended in offer an attractive possibility to change the color of the emitted light by changing the dye. We present ab initio calculations within density-functional theory of the HOMO/ LUMO energies for dipyrrolomethane dyes, polyphenylenevinylene and

  8. Study on the dyeing properties of moderate temperature reactive dyes%中温活性染料上染性能的研究

    Institute of Scientific and Technical Information of China (English)

    朱斌; 胡敏亚

    2014-01-01

    The dyeing properties of reactive dye are evaluated by dyeing characteristic values such as substantivity, exhaustion, fixation and reactivity, also migration index (MI) and level dyeing factor (LDF) are investigated to characterize migration property and level dyeing property. Two kinds of moderate temperature reactive dye were used to dye cotton knitted fabric by exhaust dyeing, then the dyeing characteristic is evaluated. The migration index and level dyeing factor were obtained in order to analyze the dyeing property of different dyes.%采用活性染料的染色特征值(S、E、F、R值)来评价染料的性能,并结合移染指数MI和匀染因子LDF评价染料的移染性和匀染性。通过选择2种中温活性染料,采用浸染工艺进行纯棉针织布的打样染色试验,测定各种染料的染色特征值,通过计算得出移染指数和匀染因子,并分析不同染料的上染性能。

  9. Tracer gas dispersion in ducts-study of a new compact device using arrays of sonic micro jets

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.R. [Instituto Nacional de Engenharia e Tecnologia Industrial (INETI), Lisboa (Portugal); Afonso, C.F. [Faculdade de Engenharia, Universidade do Porto Departmento de Mecanica e Gestao Industrial, Porto (Portugal)

    2004-07-01

    One of the most feasible ways to measure duct airflows is by tracer gas techniques, especially for complex situations when the duct lengths are short as well as their access, which makes extremely difficult or impossible other methods to be implemented. One problem associated with the implementation of tracer gas technique when the ducts lengths are short is due to the impossibility of achieving complete mixing of the tracer with airflow and its sampling. In this work, the development of a new device for the injection of tracer gas in ducts is discussed as well as a new tracer-sampling device. The developed injection device has a compact tubular shape, with magnetic fixation to be easy to apply in duct walls. An array of sonic micro jets in counter current direction, with the possibility of angular movement according to its main axle ensures a complete mixing of the tracer in very short distances. The tracer-sampling device, with a very effective integration function, feeds the sampling system for analysis. Both devices were tested in a wind tunnel of approximately 21 m total length. The tests distances between injection and integration device considered were: X/Dh = 22; X/Dh = 4; X/Dh 2; and X/Dh = 1. For very short distances of X/Dh = 2 and X/Dh = 1, semi-empirical expressions were needed. A good reproducibility of airflow rate values was obtained. These preliminary tests showed that the practical implementation of tracer gas techniques in HVAC systems for measuring airflow rates with a very short mixing distance is possible with the devices developed. (author)

  10. Dye Painting!

    Science.gov (United States)

    Johnston, Ann

    This resource provides practical instructions for applying color and design directly to fabric. Basic information about the dye painting process is given. The guide addresses the technical aspects of fabric dye and color use and offers suggestions for fabric manipulation and dye application in order to achieve various design effects. This…

  11. Dye Painting!

    Science.gov (United States)

    Johnston, Ann

    This resource provides practical instructions for applying color and design directly to fabric. Basic information about the dye painting process is given. The guide addresses the technical aspects of fabric dye and color use and offers suggestions for fabric manipulation and dye application in order to achieve various design effects. This…

  12. Sorption and desorption studies of a reactive azo dye on effective disposal of redundant material.

    Science.gov (United States)

    Çelekli, Abuzer; Bozkurt, Hüseyin

    2013-07-01

    The effective disposal of redundant elephant dung (ED) is important for environmental protection and utilization of resource. The aim of this study was to remove a toxic-azo dye, Reactive Red (RR) 120, using this relatively cheap material as a new adsorbent. The FTIR-ATR spectra of ED powders before and after the sorption of RR 120 and zero point charge (pHzpc) of ED were determined. The sorption capacity of ED for removing of RR 120 were carried out as functions of particle size, adsorbent dose, pH, temperature, ionic strength, initial dye concentration, and contact time. Sorption isotherm, kinetic, activation energy, thermodynamic, and desorption parameters of RR 120 on ED were studied. The sorption process was found to be dependent on particle size, adsorbent dose, pH, temperature, ionic strength, initial dye concentration, and contact time. FTIR-ATR spectroscopy indicated that amine and amide groups have significant role on the sorption of RR 120 on ED. The pHzpc of ED was found to be 7.3. Sorption kinetic of RR 120 on ED was well described by sigmoidal Logistic model. The Langmuir isotherm was well fitted to the equilibrium data. The maximum sorption capacity was 95.71 mg g(-1). The sorption of RR 120 on ED was mainly physical and exothermic according to results of D-R isotherm, Arrhenius equation, thermodynamic, and desorption studies. The thermodynamic parameters showed that this process was feasible and spontaneous. This study showed that ED as a low-cost adsorbent had a great potential for the removal of RR 120 as an alternative eco-friendly process.

  13. Ab initio study of energy-level alignments in polymer-dye blends

    Science.gov (United States)

    Pasveer, W. F.; Bobbert, P. A.; Michels, M. A. J.; Langeveld-Voss, B. M. W.; Schoo, H. F. M.; Bastiaansen, J. J. A. M.

    2003-11-01

    Polymers with a small amount of dye blended in offer an attractive possibility to change the color of the emitted light by changing the dye. We present ab initio calculations within density-functional theory of the HOMO/LUMO energies for dipyrrolomethane dyes, polyphenylenevinylene and polyfluorene. Special attention is paid to the trends in these energies with variation of the sidegroups of the dyes as observed in cyclic-voltammetry measurements. From the energy-level alignments between dye and polymer we can understand and predict electron and hole trapping, crucial processes for the functioning of light-emitting devices based on these blends.

  14. Rainfall simulation experiments to study sediment redistribution using rare earth element oxides as tracers under conventional and conservation agricultural practices

    Science.gov (United States)

    Tóth, Adrienn; Jakab, Gergely; Sipos, Péter; Karlik, Máté; Madarász, Balázs; Zacháry, Dóra; Szabó, Judit; Szalai, Zoltán

    2017-04-01

    Rare earth elements (REE) have very favourable characteristics for being ideal sediment tracers as they are characterised by strong binding to soil particles, low mobility, low background concentration in soils, environmental benignity, high analytical sensitivity and they can be detected relatively easily and inexpensively in soils. The group of REEs consist of 16 elements with similar chemical properties, but at the same time, they are clearly distinguishable enabling multiple tracking of sediment deriving from different parts of the studied area, as well as mapping redistribution processes by appropriate designing of subareas marked by different REEs. In this study, rainfall simulation experiments were carried out to compare the loss and redistribution of soil sediments in two plots under conventional and conservation agricultural practices. Five different rainfall intensities (up to 80 mm/h) were applied to both plots. Sources and pathways of sediments within the two plots were studied using REE-oxides as tracers. Approximately 1,000 mg/kg of Er2O3, Ho2O3 and Sm2O3 (calculated to the upper 1 cm of the soil) were dispersed to the soil surface with banded distribution; each transversal band covered the third of the surface are of the plots. Concentration of the REE-oxides in the sediment leaving the plots, and that of the surface soil before and after the experiment were analysed by X-Ray fluorescence spectrometry. Significant sediment losses were found for both plots after the experiments, with slightly different characteristics between the conventional and conservation ones. Highest difference in loss of added REEs was found in the upper third of the plots with 81 ± 19% in the conventional and 71 ± 21% in the conservation ones. These values have been equalized downwards with almost complete losses in the lower third of the plots (99 ± 2% and 97 ± 4%, respectively). Only very small part of the removed sediment has been accumulated in the lower parts of the

  15. Photophysical studies of dipolar organic dyes that feature a 1,3-cyclohexadiene conjugated linkage: the implication of a twisted intramolecular charge-transfer state on the efficiency of dye-sensitized solar cells.

    Science.gov (United States)

    Chen, Kuan-Fu; Chang, Che-Wei; Lin, Ju-Ling; Hsu, Ying-Chan; Yeh, Ming-Chang P; Hsu, Chao-Ping; Sun, Shih-Sheng

    2010-11-15

    A detailed study of the synthesis and photophysical properties of a new series of dipolar organic photosensitizers that feature a 1,3-cyclohexadiene moiety integrated into the π-conjugated structural backbone has been carried out. Dye-sensitized solar cells (DSSCs) based on these structurally simple dyes have shown appreciable photo-to-electrical energy conversion efficiency, with the highest one up to 4.03 %. Solvent-dependent fluorescence studies along with the observation of dual emission on dye 4 b and single emission on dyes 4 a and 32 suggest that dye 4 b possesses a highly polar emissive excited state located at a lower-energy position than at the normal emissive excited state. A detailed photophysical investigation in conjunction with computational studies confirmed the twisted intramolecular charge-transfer (TICT) state to be the lowest emissive excited state for dye 4 b in polar solvents. The relaxation from higher-charge-injection excited states to the lowest TICT state renders the back-electron transfer process a forbidden one and significantly retards the charge recombination to boost the photocurrent. The electrochemical impedance under illumination and transient photovoltage decay studies showed smaller charge resistance and longer electron lifetime in 4 b-based DSSC compared to the DSSCs with reference dyes 4 a and 32, which further illustrates the positive influence of the TICT state on the performance of DSSCs.

  16. The Comparative Study on the Rapid Decolorization of Azo, Anthraquinone and Triphenylmethane Dyes by Anaerobic Sludge

    Directory of Open Access Journals (Sweden)

    Daizong Cui

    2016-10-01

    Full Text Available An anaerobic sludge (AS, capable of decolorizing a variety of synthetic dyes, was acclimated and is reported here. The sludge presented a much better dye decolorizing ability than that of different individual strains. A broad spectrum of dyes could be decolorized by the sludge. Continuous decolorization tests showed that the sludge exhibited the ability to decolorize repeated additions of dye. The chemical oxygen demand (COD removal rate of the dye wastewater reached 52% after 12 h of incubation. Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE profiles revealed that the microbial community changed as a result of varying initial concentrations of dyes. Phylogenetic analysis indicated that microbial populations in the sludge belonged to the phyla Acidobacteria, Firmicutes, Bacteroidetes, Chloroflexi and Proteobacteria. The degradation products of the three types of dye were identified. For azo dyes, the anaerobic sludge converted Methyl Orange to N,N-dimethylbenzene-1,4-diamine and 4-aminobenzenesulfonic acid; for triphenylmethane dyes, after Malachite Green was decolorized, the analyzed products were found to be a mixture of N,N-dimethylbenzenamine, 3-dimethyl-aminophenol and 4-dimethylaminobenzophenone; for anthraquinone dyes, two products (acetophenone and 2-methylbenzoic acid were observed after Reactive Blue 19 decolorization. Together, these results suggest that the anaerobic sludge has promising potential for use in the treatment of industrial wastewater containing various types of dyes.

  17. Comparative use of bacterial, algal and protozoan tests to study toxicity of azo- and anthraquinone dyes.

    Science.gov (United States)

    Novotný, Cenek; Dias, Nicolina; Kapanen, Anu; Malachová, Katerina; Vándrovcová, Marta; Itävaara, Merja; Lima, Nelson

    2006-06-01

    Toxicity of two azo dyes (Reactive Orange 16 (RO16); Congo Red (CR)) and two anthraquinone dyes (Remazol Brilliant Blue R (RBBR); Disperse Blue 3 (DB3)) were compared using bacterium Vibrio fischeri, microalga Selenastrum capricornutum and ciliate Tetrahymena pyriformis. The following respective endpoints were involved: acute toxicity measured as bacterial luminescence inhibition, algal growth inhibition, and the effects on the protozoa including viability, growth inhibition, grazing effect and morphometric effects. In addition, mutagenicity of the dyes was determined using Ames test with bacterium Salmonella typhimurium His(-). DB3 dye was the most toxic of all dyes in the bacterial, algal and protozoan tests. In contrast to other dyes, DB3 exhibited mutagenic effects after metabolic activation in vitro in all S. typhimurium strains used. Of the methods applied, the algal test was the most sensitive to evaluate toxicity of the dyes tested.

  18. Photophysical and laser characteristics of pyrromethene 567 dye: Experimental and theoretical studies

    Indian Academy of Sciences (India)

    K K Jagtap; D K Maity; A K Ray; K Dasgupta; S K Ghosh

    2010-11-01

    Narrow-band laser performance of alcohol solutions of pyrromethene 567 (PM567) and rhodamine 6G (RH6G) dye was investigated using a home-made GIG- configured dye laser, excited by the second-harmonic radiation (at 532 nm) of a pulsed Nd:YAG laser. Higher laser efficiency was observed with PM567 dye (∼ 23% peak) in comparison to the commonly used RH6G dye (16.5%), in spite of much lower fluorescence quantum efficiency of the PM567 (0.83) vis-à-vis RH6G (0.98) dye solutions in ethanol. First principle-based electronic structure calculations were performed on PM567 dye in the ground (0) and excited states (1) using density functional theory to elucidate the structure and photophysical properties of the dye.

  19. Digital Frequency Domain Fluorometry and the Study of Hoechst 33258 Dye-Dna Interactions

    Science.gov (United States)

    Feddersen, Brett Andrew

    Fluorescence is a powerful tool for the study of chemical and biological processes. The typical decay times of fluorescence are ideal to study events in the pico to nanosecond range. On these time scales, the motions of many biological processes can be studied. The use of frequency domain fluorometry to measure the lifetime of the excited state has been used for many years. However, the development of an acquisition system based on modern digital techniques, presented in this thesis, has opened the door to different types of experiments that previously were either too time consuming or could not be done. The use of digital techniques and the development of a method to modulate an image intensifier have made it possible to incorporate linear and matrix detectors in frequency domain fluorometry. The extension of time -resolved fluorescence measurements to linear arrays has made it possible to follow the time evolution of the emission spectra while the use of matrix detectors has permitted the measurement of the lifetime at every "pixel" of an image. The dye Hoechst 33258 has been used for many years in the study of DNA and DNA binding. However, the fluorescent properties of Hoechst 33258 are not well understood. The dye is highly quenched in aqueous solutions and becomes brightly fluorescent when bound to Acdot T rich sequences of DNA or placed in non-aqueous solutions. The fluorescence of Hoechst 33258 seems to arise from two different solvation states of the molecule. When Hoechst 33258 binds to calf thymus DNA or poly(d(A cdotT)), the molecule becomes highly fluorescent, yet the two states can still be distinguished. The two states are attributed to different binding modes of the dye. The loose binding allows access of water molecules which results in different emission properties. On the other hand, when Hoechst binds onto d(CGCGAATTCGCG) only one lifetime is observed. The single lifetime has been attributed to strong binding of the Hoechst molecule onto the AATT

  20. Packet Tracer network simulator

    CERN Document Server

    Jesin, A

    2014-01-01

    A practical, fast-paced guide that gives you all the information you need to successfully create networks and simulate them using Packet Tracer.Packet Tracer Network Simulator is aimed at students, instructors, and network administrators who wish to use this simulator to learn how to perform networking instead of investing in expensive, specialized hardware. This book assumes that you have a good amount of Cisco networking knowledge, and it will focus more on Packet Tracer rather than networking.

  1. Development of the plastic solid-dye cell for tunable solid-state dye lasers and study on its optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Do Kyeong; Lee, Jong Min; Cha, Byung Heon; Jung, E. C.; Kim, Hyun Su; Lim, Gwon

    2001-01-01

    we have fabricated solid-state dyes with PMMA and sol-gel materials. We developed single longitudianl mode solid-state dye laser with the linewidth of less than 500MHz. We have constructed a self-seeded laser and observed the increase of the output power because of self-seeding effect. We investigated the operating characteristics of the dualwave laser oscillator and DFDL with solid-state dyes. And we have constructed the 3-color solid-state dye laser oscillator and amplifier system and observed 3-color operation. We also improved the laser oscliiator with disk-type solid-state dye cell which can be translated and rotated with the help of the two stepping motors. With the help of computer control, we could constantly changed the illuminated area of the dye cell and, therefore, were able to achieve long time operation and to use almost the entire region of the solid-state dye cell.

  2. Use of stable isotope-labeled Escherichia coli as a tracer in karst aquifers

    Science.gov (United States)

    Bacterial contamination of karst aquifers is a large concern across the globe, yet bacterial transport in karst aquifers is not currently well understood. Groundwater tracers typically used in karst systems include fluorescent dyes and latex microspheres. Not only can these tracers can be cost-prohi...

  3. {sup 11}C-harmine as a potential PET tracer for ductal pancreas cancer: in vitro studies

    Energy Technology Data Exchange (ETDEWEB)

    Herlin, G.; Persson, B.; Laangstroem, B.; Aspelin, P. [Department of Diagnostic Radiology, Huddinge University Hospital, 141-86 Stockholm (Sweden); Bergstroem, M. [Uppsala University PET Centre, Uppsala (Sweden)

    2003-04-01

    Our objective was to find a tracer in diagnosing human pancreatic cancer using positron emission tomography (PET). For this purpose in vitro test of pancreatic tissues with autoradiography was used. Autoradiography was performed with {sup 11}C-harmine (a MAO-A-inhibitor) with and without competitive inhibition. Tissue preparations were obtained from normal human pancreas and pancreatic cancer. The uptake was compared with rat brain or pig brain, tissues with high expression of MAO-A. Nine autoradiography studies on 16 samples from five different human pancreatic cancers gave a significant level of specific binding of {sup 11}C-harmine in 13, and 3 samples did not give a significant level of specific binding of {sup 11}C-harmine. All 16 samples were analysed with autoradiography. Compared with rat brain, the uptake in the human cancers varied between 9 and 43% except for one tissue preparation which had a too low value for measurement. This study shows expression of MAO-A in human pancreatic cancer. This is readily characterised in vitro. The potential use of {sup 11}C-harmine in the diagnosis of pancreatic cancer using PET might be limited, but further PET studies are necessary. (orig.)

  4. Studies on biosorption of Cr(VI) on a green resin: dry cow dung powder and tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Barot, N.S.; Bagla, H.K. [Kishinchand Chellaram College, Mumbai (India). Nuclear and Radiochemistry Dept.

    2012-07-01

    The present investigation entails the application of dry cow dung powder (DCP) as an indigenous, inexpensive and eco-friendly material for the removal of Cr(VI) from aqueous medium. Batch biosorption experiments were conducted employing {sup 51}Cr(VI) as a tracer and the effect of various process parameters such as optimum pH, temperature, amount of resin, time of equilibration, agitation speed, concentration of metal ions and interfering effect of different salts etc. were studied. The kinetic studies were carried out employing various models but the best fitting was given by Lagergren Pseudo-second order model with high correlation coefficient R{sup 2} value of 0.997 and adsorption capacity of 10.20 mg/g. The thermodynamic parameters for biosorption were evaluated as {Delta}G = -2.837 kJ/mol, {Delta}H = -4.757 kJ/mol and {Delta}S = 16.64 J/mol K, which indicated spontaneous and exothermic process with high affinity of DCP for Cr(VI). Many naturally available materials are used for the biosorption of heavy metal pollutants, where most of them are physically or chemically modified. In this research work, DCP has been utilized without any pre or post chemical treatment. Thus it manifests the principle of green chemistry and proves to be an eco-friendly resin. (orig.)

  5. Open and Distance Education Systems: do they enhance Graduates' Soft Skills? The results from 2009 Universitas Terbuka Tracer Study

    Directory of Open Access Journals (Sweden)

    Dewi Juliah Ratnaningsih

    2013-11-01

    Full Text Available The vision and mission of Universitas Terbuka (UT is to become a highly qualified open and distance education institution and to provide higher education access to all communities. Graduates of UT are expected to acquire adequate knowledge, hard skills and soft skills. Soft skills play important roles in the world of work. The aim of this article is to describe: (1 whether the open and distance education systems are capable of providing graduates with soft skills, (2 how soft skills are acquired during the period of study, and (3 how are the range of soft skills acquired by graduates and required by stakeholders at work. This article uses 2009 UT tracer study, which employed survey and in-depth interviews to selected respondents and stakeholders. 2.417 pairs data (graduates and stakeholders were analysed. The rating scales were from 1 (very poor to 4 (excellent. The attributes analysed were personal, interpersonal and situational skills. The results show that learning systems that are based on individual learning and tutorial did provide graduates with soft skills. Graduates and stakeholders perceived interpersonal skills as fair. In general, soft skills required at work were time management, self-confidence, problem solving, creativity and team-work.

  6. Human ketone body production and utilization studied using tracer techniques: Regulation by free fatty acids, insulin, catecholamines, and thyroid hormones

    Energy Technology Data Exchange (ETDEWEB)

    Keller, U.; Lustenberger, M.; Mueller-Brand, J.G.; Gerber, P.P.; Stauffacher, W.

    1989-05-01

    Ketone body concentrations fluctuate markedly during physiological and pathological conditions. Tracer techniques have been developed in recent years to study production, utilization, and the metabolic clearance rate of ketone bodies. This review describes data on the roles of insulin, catecholamines, and thyroid hormones in the regulation of ketone body kinetics. The data indicate that insulin lowers ketone body concentrations by three independent mechanisms: first, it inhibits lipolysis, and thus lowers free fatty acid availability for ketogenesis; second, it restrains ketone body production within the liver; third, it enhances peripheral ketone body utilization. To assess these effects in humans in vivo, experimental models were developed to study insulin effects with controlled concentrations of free fatty acids, insulin, glucagon, and ketone bodies. Presently available data also support an important role of catecholamines in increasing ketone body concentrations. Evidence was presented that norepinephrine increases ketogenesis not only by stimulating lipolysis, and thus releasing free fatty acids, but also by increasing intrahepatic ketogenesis. Thyroid hormone availability was associated with lipolysis and ketogenesis. Ketone body concentrations after an overnight fast were only modestly elevated in hyperthyroidism resulting from increased peripheral ketone body clearance. There was a significant correlation between serum triiodothyronine levels and the ketone body metabolic clearance rate. Thus, ketone body homeostasis in human subjects resulted from the interaction of hormones such as insulin, catecholamines, and thyroid hormones regulating lipolysis, intrahepatic ketogenesis, and peripheral ketone body utilization. 58 references.

  7. EQUILIBRIUM, KINETIC, AND THERMODYNAMIC STUDIES OF HAZARDOUS DYE NEUTRAL RED BIOSORPTION BY SPENT CORNCOB SUBSTRATE

    Directory of Open Access Journals (Sweden)

    Xiuwu Yu

    2011-04-01

    Full Text Available This study focuses on the possible use of spent corncob substrate (SCS, an agricultural waste utilized after the cultivation of white rot fungus Pleurotus ostreatus, to adsorb the hazardous dye Neutral Red (NR from aqueous solutions. Natural SCS was initially characterized by using a combination of Fourier Transform Infrared Spectrometry (FTIR and Brunauer-Emmett-Teller (BET techniques. A batch adsorption study was carried out with varied solution pH, adsorption time, temperature, and initial NR concentration. It was found that NR uptake was favorable over a pH range of 4.0 to 7.0, and the equilibrium adsorption capacity can be reached within about 180 min. The biosorption data were also calculated by the pseudo-second-order kinetic model and Langmuir isotherm model. The maximum adsorption capacity was 139.1, 140.0, and 143.3 mg g-1 at 20, 30, and 40 °C, respectively. Thermodynamic parameters showed that the adsorption was a spontaneous and endothermic process. The study highlighted a new pathway to develop potential low-cost biosorbent for the removal of dye pollutants from wastewater.

  8. Thermodynamic study of β-cyclodextrin-dye inclusion complexes using gradient flow injection technique and molecular modeling

    Science.gov (United States)

    Izadmanesh, Y.; Ghasemi, Jahan B.

    2016-08-01

    Gradient flow injection technique-diode array spectrophotometry was applied for β-cyclodextrin (β-CD)-dye inclusion complex studies. A single injection of a small amount of mixed β-CD-dye solution (100 μl) into the carrier solution of the dye and recording the spectra gave the titration data. The mole ratio data were calculated by calibrating the dispersion pattern using a calibrator dye (rose bengal). Model-based multivariate methods were used to analyze the spectral-mole ratio data and, as a result, estimate stability constants and concentration-spectral profiles. Reliability was tested by applying this method to study the β-CD host-guest complexes with several dyes as guest molecules. Singular value decomposition (SVD) was used to select the chemical model and reduce noise. Molecular modeling provided the ability to predict the guest conformation-orientation (posing) within the cavity of β-CD and the nature of the involved interactions. Among those dyes showing observable spectral variation, the stoichiometric ratio of β-CD: dye (and log Kf) of methyl orange, fluorescein, phenol red, 4-(2-pyridylazo) resorcinol (PAR), and crystal violet were calculated to be 1:1 (4.26 ± 0.01), 1:1 (1.53 ± 0.08), 1:1 (3.11 ± 0.04), 1:1 (1.06 ± 0.12), and 2:1 (5.27 ± 0.03), respectively. Compared with the classical method of titration, this method is simple and fast and has the advantage of needing reduced human interference. Molecular modeling facilitates a better understanding of the type of interactions and conformation of guest molecules in the β-CD cavity. The details of the proposed method are discussed in this paper.

  9. Bengal Gram Seed Husk as an adsorbent for the removal of dye from aqueous solutions – Batch studies

    Directory of Open Access Journals (Sweden)

    M.C. Somasekhara Reddy

    2017-05-01

    Full Text Available The feasibility of using Indian Seed Husk of Bengal Gram (Scientific Name: Cicer arietinum (SHBG, abundantly available in and around the Kurnool in Andhra Pradesh, for the anionic dye (Congo red, CR adsorption from aqueous solution, has been investigated as a low cost and an eco-friendly adsorbent. Adsorption studies were conducted on a batch process, to study the effects of contact time, initial concentration of CR, de-sorption and pH. Maximum colour removal was observed at lower pH. The dye attained equilibrium approximately at 1, 1.5, 2 and 2.5 h for dye concentrations 25, 50, 75 and 100 mg/l respectively. The present dye removal decreased from 89% to 74% as the dye concentration has been increased from 25 mg/l to 100 mg/l. A maximum removal of 92% is obtained at lower pH. Adsorption decreases with increase in pH. Maximum de-sorption of 26.4% is achieved in water medium at pH 11.95. The equilibrium data were analyzed by the Langmuir and Freundlich isotherms. The data fitted well with the Langmuir model, with a maximum adsorption capacity of 41.66 mg g−1. The pseudo-second-order kinetics was the best for the adsorption of CR, by SHBG with good correlation. The results suggest that SHBG is a potential low-cost adsorbent for the CR dye removal from synthetic dye wastewater.

  10. Thermodynamic study of β-cyclodextrin-dye inclusion complexes using gradient flow injection technique and molecular modeling.

    Science.gov (United States)

    Izadmanesh, Y; Ghasemi, Jahan B

    2016-08-05

    Gradient flow injection technique-diode array spectrophotometry was applied for β-cyclodextrin (β-CD)-dye inclusion complex studies. A single injection of a small amount of mixed β-CD-dye solution (100μl) into the carrier solution of the dye and recording the spectra gave the titration data. The mole ratio data were calculated by calibrating the dispersion pattern using a calibrator dye (rose bengal). Model-based multivariate methods were used to analyze the spectral-mole ratio data and, as a result, estimate stability constants and concentration-spectral profiles. Reliability was tested by applying this method to study the β-CD host-guest complexes with several dyes as guest molecules. Singular value decomposition (SVD) was used to select the chemical model and reduce noise. Molecular modeling provided the ability to predict the guest conformation-orientation (posing) within the cavity of β-CD and the nature of the involved interactions. Among those dyes showing observable spectral variation, the stoichiometric ratio of β-CD: dye (and log Kf) of methyl orange, fluorescein, phenol red, 4-(2-pyridylazo) resorcinol (PAR), and crystal violet were calculated to be 1:1 (4.26±0.01), 1:1 (1.53±0.08), 1:1 (3.11±0.04), 1:1 (1.06±0.12), and 2:1 (5.27±0.03), respectively. Compared with the classical method of titration, this method is simple and fast and has the advantage of needing reduced human interference. Molecular modeling facilitates a better understanding of the type of interactions and conformation of guest molecules in the β-CD cavity. The details of the proposed method are discussed in this paper.

  11. Study of Light Harvesting Properties of Different Classes of Metal-Free Organic Dyes in TiO2 Based Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Ratna Chauhan

    2014-01-01

    Full Text Available In dye-sensitized solar cells, the photosensitization of TiO2 thin film semiconductor was accomplished by using different classes of metal-free (fluorone, triarymethane, azo and thiazine based organic dyes as photosensitizer. The broad electronic absorption spectra of these dyes have been obtained in the visible region due to the presence of chromophoric groups in these dyes. The contribution of these dyes as light harvesting species is seen from the photocurrent action spectrum of the cell. Here, we report the sensitization activity of these dyes in terms of current-potential curve, open-circuit potential, fill factor, IPCE, and overall solar energy conversion efficiency which have been evaluated under 100 mW/cm2 light intensity. The results suggest that dyes based on fluorone and azo groups are promising candidates for high performance, dye-sensitized solar cells because of better anchoring groups (–COOH, –OH, and –SO3- present in these dyes. Better anchorage of dyes to the surface of TiO2 semiconductor helps in charge transfer phenomenon.

  12. Synthesis, Characterization, Molecular Modeling, and DNA Interaction Studies of Copper Complex Containing Food Additive Carmoisine Dye.

    Science.gov (United States)

    Shahabadi, Nahid; Akbari, Alireza; Jamshidbeigi, Mina; Khodarahmi, Reza

    2016-06-02

    A copper complex of carmoisine dye; [Cu(carmoisine)2(H2O)2]; was synthesized and characterized by using physico-chemical and spectroscopic methods. The binding of this complex with calf thymus (ct) DNA was investigated by circular dichroism, absorption studies, emission spectroscopy, and viscosity measurements. UV-vis results confirmed that the Cu complex interacted with DNA to form a ground-state complex and the observed binding constant (2× 10(4) M(-1)) is more in keeping with the groove bindings with DNA. Furthermore, the viscosity measurement result showed that the addition of complex causes no significant change on DNA viscosity and it indicated that the intercalation mode is ruled out. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrogen bonds and van der Waals interactions played major roles in the reaction. The results of circular dichroism (CD) suggested that the complex can change the conformation of DNA from B-like form toward A-like conformation. The cytotoxicity studies of the carmoisine dye and its copper complex indicated that both of them had anticancer effects on HT-29 (colon cancer) cell line and they may be new candidates for treatment of the colon cancer.

  13. Transition Metal Polypyridine Complexes: Studies of Mediation in Dye-Sensitized Solar Cells and Charge Separation

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, C. Michael [Colorado State Univ., Fort Collins, CO (United States). Dept. of Chemistry; Prieto, Amy L. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Chemistry

    2017-02-08

    The Elliott group has long been supported by DOE for studies of cobalt(II/III) trisbypiridine (DTB) mediator complexes in dye sensitized solar cells. Previous work demonstrated that Co(II/III) chemistry is sensitive to the environment, showing unprecedented electrode-surface and electrolyte dependant voltammetry. In electrolytes that have large lipophilic cations, voltammetry of the [Co(DTB)3]2+/3+ couple is nearly Nernstian in appearance on nominally oxide-free metal surfaces. In contrast, on semiconductor electrodes in electrolytes with small, hard cations such as Li+, the electron transfer rates are so slow that it is difficult to measure any Faradaic current even at overpotentials of ±1 V. These studies are of direct relevance to the operation of cobalt-based mediators in solar cells. The research has also shown that these mediators are compatible with copper phenantroline based dyes, in contrast to I- due to the insolubility of CuI.

  14. Source apportionment of atmospheric water over East Asia - a source tracer study in CAM5.1

    Science.gov (United States)

    Pan, Chen; Zhu, Bin; Gao, Jinhui; Kang, Hanqing

    2017-02-01

    The atmospheric water tracer (AWT) method is implemented in the Community Atmosphere Model version 5.1 (CAM5.1) to quantitatively identify the contributions of various source regions to precipitation and water vapour over East Asia. Compared to other source apportionment methods, the AWT method was developed based on detailed physical parameterisations, and can therefore trace the behaviour of atmospheric water substances directly and exactly. According to the simulation, the northern Indian Ocean (NIO) is the dominant oceanic moisture source region for precipitation over the Yangtze River valley (YRV) and southern China (SCN) in summer, while the north-western Pacific (NWP) dominates during other seasons. Evaporation over the South China Sea (SCS) is responsible for only 2.7-3.7 % of summer precipitation over the YRV and SCN. In addition, the Indo-China Peninsula is an important terrestrial moisture source region (annual contribution of ˜ 10 %). The overall relative contribution of each source region to the water vapour amount is similar to the corresponding contribution to precipitation over the YRV and SCN. A case study for the SCS shows that only a small part ( ≤ 5.5 %) of water vapour originates from local evaporation, whereas much more water vapour is supplied by the NWP and NIO. In addition, because evaporation from the SCS represents only a small contribution to the water vapour over the YRV and SCN in summer, the SCS mainly acts as a water vapour transport pathway where moisture from the NIO and NWP meet.

  15. Contact dermatitis to hair dyes in a Danish adult population: an interview-based study

    DEFF Research Database (Denmark)

    Søsted, H; Hesse, U; Menné, T

    2005-01-01

    BACKGROUND: Contact allergy to hair dye ingredients is a well-known entity seen both in consumers using hair dyes and among hairdressers with occupational contact dermatitis. Surveys show that consumers with even severe adverse skin reactions to hair dyes only rarely contact the healthcare services....... The frequency of hair dye-induced skin reactions in the consumer population is unknown. OBJECTIVES: An epidemiological investigation with the aim of establishing the proportion of hair dye-induced skin reactions was performed in a population-based sample. METHODS: A representative random sample (n = 4000......) was taken of the Danish adult population. Personal interview questions were asked regarding adverse skin reactions to hair dyes, either compatible with a classical allergic eczematous reaction with redness, scaling and itching or a severe allergic reaction with oedema of the forehead and face. The response...

  16. Study of large eddy simulation of the effects of boundary layer convection on tracer uplift and transport

    Science.gov (United States)

    Huang, Qian; Wang, Rong

    2016-04-01

    Using large eddy model (LEM) and observed data from Dunhuang meteorological station during the intensive period of land-atmosphere interaction field experiment over arid region of North-west China, a series of sensitivity experiments have been performed to investigate the effects of the surface heat flux and wind shear on the strength and the organization of boundary layer convection as well as the growth of the convective boundary layer (CBL). The results show that surface heat flux increases with constant wind shear will give rise to a thicker and warmer CBL, stronger convections and larger thermal eddies due to intense surface turbulence transporting more energy to the upper layer. On the other hand wind shear increases with constant surface heat flux lead to a thicker and warmer CBL because of the entrainment of warm air from the inversion layer to the mixed layer, while the boundary layer convection became weaker with broken thermal eddies. To investigate the quantitative linkage of surface heat flux, wind shear with the tracer uplift rate and transport height, a passive tracer with a constant value of 100 was added at all model levels below the 100 m in all simulations. The least square analysis reveals that the tracer uplift rate increases linearly with the surface heat flux when wind shear is less than 10.5×10-3 s-1 owing to the enhancement of the downward transport of higher momentum. However, the tracer uplift rate decreases with increasing wind shear when the surface heat flux is less than 462.5 W/m2 because of the weakened convection. The passive tracer in the model is also shown to be transported to the higher altitude with increasing surface heat flux and under constant wind shear. However, under a constant surface heat flux, the tracer transport height increases with increasing wind shear only when the shear is above a certain threshold and this threshold depend on the magnitude of surface heat fluxes.

  17. Uranium-series radionuclides as tracers of geochemical processes in Long Island Sound. [Natural /sup 210/Pb tracer study of estuarine geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Benninger, L.K.

    1976-05-01

    An estuary can be visualized as a membrane between land and the deep ocean, and the understanding of the estuarine processes which determine the permeability of this membrane to terrigenous materials is necessary for the estimation of fluxes of these materials to the oceans. Natural radionuclides are useful probes into estuarine geochemistry because of the time-dependent relationships among them and because, as analogs of stable elements, they are much less subject to contamination during sampling and analysis. In this study the flux of heavy metals through Long Island Sound is considered in light of the material balance for excess /sup 210/Pb, and analyses of concurrent seston and water samples from central Long Island Sound are used to probe the internal workings of the estuary.

  18. Isotherm and kinetic studies of Burazol Blue ED dye biosorption by dried anaerobic sludge.

    Science.gov (United States)

    Caner, Necmettin; Kiran, Ismail; Ilhan, Semra; Iscen, Cansu Filik

    2009-06-15

    Biosorption potential of dried anaerobic sludge (DAS) for Burazol Blue ED (BB) was studied with respect to pH, equilibrium time, initial dye concentrations and temperature to determine equilibrium and kinetic models. The most suitable pH, equilibrium time and initial dye concentration were determined as 0.5+/-0.03, 75 min and 150 mg/L, respectively, at a biomass dosage of 0.4 g/L and 25 degrees C+/-1.0. The equilibrium data was best described by the Langmuir isotherm model. Maximum uptake capacity (q(m)) of DAS for the dyestuff (BB) were 118.3, 125.8 and 127.5mg/g biomass at temperatures of 25, 40 and 50 degrees C, respectively, indicating that the biosorption process is spontaneous and favored at higher temperatures. The overall biosorption process was best described by pseudo-second-order kinetic model. Gibbs free energy changes were calculated as -356.8, -519.7 and -520.6J/mol at 25, 40 and 50 degrees C, respectively.

  19. A STUDY OF CLINICAL, PATHOLOGICAL AND BIOCHEMICAL FINDINGS IN PATIENTS WHO ATTEMPTED SUICIDE BY HAIR DYE SUPERVASMOL 33 INGESTION

    Directory of Open Access Journals (Sweden)

    Sudheer Babu

    2015-06-01

    Full Text Available BACKGROUND : All the patient in the study consumed the hair dye available in the market with the trade name Supervasmol 33. The prevalence of Super vasmol 33 hair dye poisoning has been on a surge for the past 2 - 3 years as has been observed by the increase in number of cases being admitted into the hospitals. It was observed that the tendency of poisoning by Super vasmol 33 hair dye was more in females than in males and was more in the age group of 15 - 35 years, as with any other poisoning. METERIALS AND METHODS: Study of Clinical, pathological and biochemical findings in patients who attempted suicide by hair dye ingestion (Supervasmol 3 who were admitted in Government General Hospital/Guntur medical college, Guntur during June 2013 to March 2015 brought to emergency department and those who were admitted into the HDU, ICU and medical wards of the hospital, after the following exclusion criteria were ruled out. RESULTS: A significant statistical correlation was found to exist between development of AKI and the levels of CPK in blood, rhabdomyolysis and hyperkalemia. The morbidity rates were 100% for angioedema, 58% for rhabdomyolysis and 32% for acute kidney injury (AKI. Institutional mortality rate was about 8% due to refractory hemodynamic shock. CONCLUSION: As the burden of handling Supervasmol 33 hair dye poisoning cases has been recently increasing, primary care physicians, intensive care physicians and nephrologists need to be aware of its clinical manifestation and management

  20. Fractional Factorial Design Study on the Performance of GAC-Enhanced Electrocoagulation Process Involved in Color Removal from Dye Solutions

    Directory of Open Access Journals (Sweden)

    Iuliana Gabriela Breaban

    2013-07-01

    Full Text Available The aim of this study was to determine the effects of main factors and interactions on the color removal performance from dye solutions using the electrocoagulation process enhanced by adsorption on Granular Activated Carbon (GAC. In this study, a mathematical approach was conducted using a two-level fractional factorial design (FFD for a given dye solution. Three textile dyes: Acid Blue 74, Basic Red 1, and Reactive Black 5 were used. Experimental factors used and their respective levels were: current density (2.73 or 27.32 A/m2, initial pH of aqueous dye solution (3 or 9, electrocoagulation time (20 or 180 min, GAC dose (0.1 or 0.5 g/L, support electrolyte (2 or 50 mM, initial dye concentration (0.05 or 0.25 g/L and current type (Direct Current—DC or Alternative Pulsed Current—APC. GAC-enhanced electrocoagulation performance was analyzed statistically in terms of removal efficiency, electrical energy, and electrode material consumptions, using modeling polynomial equations. The statistical significance of GAC dose level on the performance of GAC enhanced electrocoagulation and the experimental conditions that favor the process operation of electrocoagulation in APC regime were determined. The local optimal experimental conditions were established using a multi-objective desirability function method.

  1. NOAA EPA Near-Roadway Sound Barrier Atmospheric Tracer Study 2008

    Science.gov (United States)

    A roadway toxics dispersion study was conducted at the Idaho National Laboratory to document the effects on concentrations of roadway emissions behind a roadside sound barrier in various conditions of atmospheric stability. The key finding was that reduced concentrations were me...

  2. Using thermal tracers to estimate flow velocities of shallow flows: laboratory and field experiments

    Directory of Open Access Journals (Sweden)

    Lima Rui L.P. de

    2015-09-01

    Full Text Available Accurate measurement of shallow flows is important for hydraulics, hydrology and water resources management. The objective of this paper is to discuss a technique for shallow flow and overland flow velocity estimation that uses infrared thermography. Laboratory flumes and different bare, vegetated and paved field surfaces were used to test the technique. Results show that shallow flow surface velocities estimated using thermal tracers and infrared technology are similar to estimates obtained using the Acoustic Doppler Velocimeter; similar results were also obtained for overland flow velocity estimates using thermography, here comparing with the dye tracer technique. The thermographic approach revealed some potential as a flow visualization technique, and leaves space for future studies and research.

  3. Practical uses of a quantitative renal scintillation camera study. [/sup 131/I tracer techniques

    Energy Technology Data Exchange (ETDEWEB)

    Bueschen, A.J.; Lloyd, L.K.

    1976-10-01

    A quantitative renal scintillation camera study has been described for the evaluation of total renal function and the split function of the two kidneys by a noninvasive technic. It requires no patient preparation, is not affected by bowel gas, and no allergic reactions have been reported. Six cases are reported to illustrate its usefulness with renal tumors, neurogenic bladders, pyelonephritis, nephrolithiasis, congenital anomalies, and renal insufficiency.

  4. Using natural isotopes as tracers of Saharan dust dispersion: a case study in the Azores - Portugal

    Directory of Open Access Journals (Sweden)

    Charles Holmes

    2005-06-01

    Full Text Available After mineral aerosol transport from Sahara Desert, through the North Atlantic, analysis on beryllium 7 and lead 210 were carried out on Azorean aerosol samples. Knowing about the isotope activity of beryllium 7 and lead 210 on aerosol, will permit to study stratospheric intrusions and others physical characteristics of the North Atlantic atmospheric transport. Based on beryllium 7/lead 210 ratios it is possible to differentiate insular and marine aerosol from continental aerosol.

  5. Photophysical Studies of a New Water Soluble Indocarbocyanine Dye Adsorbed onto Microcrystalline Cellulose and b-Cyclodextrin

    Directory of Open Access Journals (Sweden)

    Luis F. Vieira Ferreira

    2013-05-01

    Full Text Available A water-soluble indocarbocyanine dye was synthesized and its photophysics were studied for the first time on two solid hosts, microcrystalline cellulose and b-cyclodextrin, as well as in homogeneous media. The inclusion of the indocarbocyanine moiety onto microcrystalline cellulose increased the dye aggregation with both H and J aggregates being formed. Adsorption on b-cyclodextrin enhanced aggregation in a similar way. The fluorescence quantum yields were determined for the powdered samples of the cyanine dye on the two hosts and a significant increase was observed relative to homogeneous solution. A remarkable concentration dependence was also detected in both cases. A lifetime distribution analysis has shown that the indocarbocyanine dye mainly occupies the amorphous part of cellulose and is not entrapped in the crystalline part of this host. In the b-CD case, the adsorption occurs outside the host cavity. In both hosts a strong concentration quenching effect is observed and only monomers emit. Both adsorptions may be explained by stereochemical constraints imposed by the two long sulphoethyl tails linked to nitrogen atoms of the indocarbocyanine dye.

  6. Radioassay of granulocyte chemotaxis. Studies of human granulocytes and chemotactic factors. [/sup 51/Cr tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Gallin, J.I.

    1974-01-01

    The above studies demonstrate that the /sup 51/Cr radiolabel chemotactic assay is a relatively simple and objective means for studying leukocyte chemotaxis in both normal and pathological conditions. Application of this method to studies of normal human chemotaxis revealed a relatively narrow range of normal and little day-to-day variability. Analysis of this variability revealed that there is more variability among the response of different granulocytes to a constant chemotactic stimulus than among the chemotactic activity of different sera to a single cell source. Utilizing the /sup 51/Cr radioassay, the abnormal granulocyte chemotactic behavior reported in Chediak-Higashi syndrome and a patient with recurrent pyogenic infections and mucocutaneous candidiasis has been confirmed. The /sup 51/Cr chemotactic assay has also been used to assess the generation of chemotactic activity from human serum and plasma. The in vitro generation of two distinct chemotactic factors were examined; the complement product (C5a) and kallikrein, an enzyme of the kinin-generating pathway. Kinetic analysis of complement-related chemotactic factor formation, utilizing immune complexes or endotoxin to activate normal sera in the presence or absence of EGTA as well as kinetic analysis of activation of C2-deficient human serum, provided an easy means of distinguishing the classical (antibody-mediated) complement pathway from the alternate pathway. Such kinetic analysis is necessary to detect clinically important abnormalities since, after 60 min of generation time, normal chemotactic activity may be present despite complete absence or inhibition of one complement pathway. The chemotactic factor generated by either pathway of complement activation appears to be predominately attributable to C5a.

  7. Kinetic, isotherm and thermodynamic studies of amaranth dye biosorption from aqueous solution onto water hyacinth leaves.

    Science.gov (United States)

    Guerrero-Coronilla, Imelda; Morales-Barrera, Liliana; Cristiani-Urbina, Eliseo

    2015-04-01

    The present study explored the kinetics, equilibrium and thermodynamics of amaranth (acid red 27) anionic dye (AD) biosorption to water hyacinth leaves (LEC). The effect of LEC particle size, contact time, solution pH, initial AD concentration and temperature on AD biosorption was studied in batch experiments. AD biosorption increased with rising contact time and initial AD concentration, and with decreasing LEC particle size and solution pH. Pseudo-second-order chemical reaction kinetics provided the best correlation for the experimental data. Isotherm studies showed that the biosorption of AD onto LEC closely follows the Langmuir isotherm, with a maximum biosorption capacity of about 70 mg g(-1). The thermodynamic parameters confirm that AD biosorption by LEC is non-spontaneous and endothermic in nature. Results indicate that LEC is a strong biosorbent capable of effective detoxification of AD-laden wastewaters.

  8. Dorsal and median Raphe nuclei projection to MD of Thalamus in rat: A retrograde tracer study

    Directory of Open Access Journals (Sweden)

    Pas Bakhsh P

    2000-06-01

    Full Text Available In order to understand the function of mammalians serotonin system, we have to know the anatomical structure, because physiological changes are influenced through the anatomical changes. A number of thalamic nuclei are associated with functions known to be influenced by serotonergic input in brainstem, among them mediodorsal thalamic nucleus has relationship with limbic system and prefrontal cortex. The precise topographical projections of mesencephalic raphe nuclei to the MD nucleus of thalamus were identified in the rat using horseradish peroxidase (HRP retrograde tracing substance. Injection of HRP in MD labeled a large number of neurons in rostral to caudal part of dorsal raphe nucleus. It exhibited a strong number of neurons in ipsilateral part of DR and a few cells in its contralateral part. Numerously labeled cells were also observed ipsilateral in rostral and medial part of MnR (86% and a few cells in it's contralateral part. The present study has provided that the MD innervation by DR is more greater in density than that observed at the MnR. Upon these results and previous study, mesencephalic raphe nuclei are involved in several specific functions of thalamus as limbic system behavioral mechanism. A much more detailed knowledge is needed to show topographic relationships between mesencephalic raphe nuclei and forebrain.

  9. Kinetic and Related Determinants of Plasma Triglyceride Concentration in Abdominal Obesity: Multicenter Tracer Kinetic Study.

    Science.gov (United States)

    Borén, Jan; Watts, Gerald F; Adiels, Martin; Söderlund, Sanni; Chan, Dick C; Hakkarainen, Antti; Lundbom, Nina; Matikainen, Niina; Kahri, Juhani; Vergès, Bruno; Barrett, P Hugh R; Taskinen, Marja-Riitta

    2015-10-01

    Patients with obesity and diabetes mellitus have increased risk of cardiovascular disease. A major cause is an atherogenic dyslipidemia related primarily to elevated plasma concentrations of triglyceride-rich lipoproteins. The aim of this study was to clarify determinants of plasma triglyceride concentration. We focused on factors that predict the kinetics of very-low density lipoprotein 1 (VLDL1) triglycerides. A multicenter study using dual stable isotopes (deuterated leucine and glycerol) and multicompartmental modeling was performed to elucidate the kinetics of triglycerides and apoB in VLDL1 in 46 subjects with abdominal obesity and additional cardiometabolic risk factors. Results showed that plasma triglyceride concentrations were dependent on both the secretion rate (r=0.44, Ptriglycerides and VLDL1-apoB. Liver fat mass was independently and directly associated with secretion rates of VLDL1-triglycerides (r=0.56, Ptriglycerides (r=0.48, Ptriglyceride concentrations in abdominal obesity are determined by the kinetics of VLDL1 subspecies, catabolism being mainly dependent on apoC-III concentration and secretion on liver fat content. Reduction in liver fat and targeting apoC-III may be an effective approach for correcting triglyceride metabolism atherogenic dyslipidemia in obesity. © 2015 American Heart Association, Inc.

  10. Field study of time-dependent selenium partitioning in soils using isotopically enriched stable selenite tracer

    Energy Technology Data Exchange (ETDEWEB)

    Di Tullo, Pamela, E-mail: pamela.ditullo@univ-pau.fr [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Université de Pau et des Pays de l' Adour/CNRS, UMR 5254, IPREM, Hélioparc, 2 Avenue du Président Angot, 64053 Pau Cedex 9 (France); Andra, Research and Development Division, Parc de la Croix Blanche, 1-7 rue Jean Monnet, 92298 Châtenay-Malabry Cedex (France); Pannier, Florence, E-mail: florence.pannier@univ-pau.fr [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Université de Pau et des Pays de l' Adour/CNRS, UMR 5254, IPREM, Hélioparc, 2 Avenue du Président Angot, 64053 Pau Cedex 9 (France); Thiry, Yves, E-mail: yves.thiry@andra.fr [Andra, Research and Development Division, Parc de la Croix Blanche, 1-7 rue Jean Monnet, 92298 Châtenay-Malabry Cedex (France); Le Hécho, Isabelle, E-mail: isabelle.lehecho@univ-pau.fr [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Université de Pau et des Pays de l' Adour/CNRS, UMR 5254, IPREM, Hélioparc, 2 Avenue du Président Angot, 64053 Pau Cedex 9 (France); Bueno, Maïté, E-mail: maite.bueno@univ-pau.fr [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Université de Pau et des Pays de l' Adour/CNRS, UMR 5254, IPREM, Hélioparc, 2 Avenue du Président Angot, 64053 Pau Cedex 9 (France)

    2016-08-15

    A better understanding of selenium fate in soils at both short and long time scales is mandatory to consolidate risk assessment models relevant for managing both contamination and soil fertilization issues. The purpose of this study was thus to investigate Se retention processes and their kinetics by monitoring time-dependent distribution/speciation changes of both ambient and freshly added Se, in the form of stable enriched selenite-77, over a 2-years field experiment. This study clearly illustrates the complex reactivity of selenium in soil considering three methodologically defined fractions (i.e. soluble, exchangeable, organic). Time-dependent redistribution of Se-77 within solid-phases having different reactivity could be described as a combination of chemical and diffusion controlled processes leading to its stronger retention. Experimental data and their kinetic modeling evidenced that transfer towards less labile bearing phases are controlled by slow processes limiting the overall sorption of Se in soils. These results were used to estimate time needed for {sup 77}Se to reach the distribution of naturally present selenium which may extend up to several decades. Ambient Se speciation accounted for 60% to 100% of unidentified species as function of soil type whereas {sup 77}Se(IV) remained the more abundant species after 2-years field experiment. Modeling Se in the long-term without taking account these slow sorption kinetics would thus result in underestimation of Se retention. When using models based on K{sub d} distribution coefficient, they should be at least reliant on ambient Se which is supposed to be at equilibrium.

  11. Multi-tracer investigation of river and groundwater interactions: a case study in Nalenggele River basin, northwest China

    Science.gov (United States)

    Xu, Wei; Su, Xiaosi; Dai, Zhenxue; Yang, Fengtian; Zhu, Pucheng; Huang, Yong

    2017-06-01

    Environmental tracers (such as major ions, stable and radiogenic isotopes, and heat) monitored in natural waters provide valuable information for understanding the processes of river-groundwater interactions in arid areas. An integrated framework is presented for interpreting multi-tracer data (major ions, stable isotopes (2H, 18O), the radioactive isotope 222Rn, and heat) for delineating the river-groundwater interactions in Nalenggele River basin, northwest China. Qualitative and quantitative analyses were undertaken to estimate the bidirectional water exchange associated with small-scale interactions between groundwater and surface water. Along the river stretch, groundwater and river water exchange readily. From the high mountain zone to the alluvial fan, groundwater discharge to the river is detected by tracer methods and end-member mixing models, but the river has also been identified as a losing river using discharge measurements, i.e. discharge is bidirectional. On the delta-front of the alluvial fan and in the alluvial plain, in the downstream area, the characteristics of total dissolved solids values, 222Rn concentrations and δ18O values in the surface water, and patterns derived from a heat-tracing method, indicate that groundwater discharges into the river. With the environmental tracers, the processes of river-groundwater interaction have been identified in detail for better understanding of overall hydrogeological processes and of the impacts on water allocation policies.

  12. Far-infrared study of tracers of oxygen chemistry in diffuse clouds

    CERN Document Server

    Wiesemeyer, H; Heyminck, S; Hübers, H W; Menten, K M; Neufeld, D A; Richter, H; Simon, R; Stutzki, J; Winkel, B; Wyrowski, F

    2016-01-01

    Context. The chemistry of the diffuse interstellar medium rests upon three pillars: exothermic ion-neutral reactions (" cold chemistry "), endothermic neutral-neutral reactions with significant activation barriers (" warm chemistry "), and reactions on the surfaces of dust grains. While warm chemistry becomes important in the shocks associated with turbulent dissipation regions, the main path for the formation of interstellar OH and H2O is that of cold chemistry. Aims. The aim of this study is to observationally confirm the association of atomic oxygen with both atomic and molecular gas phases, and to understand the measured abundances of OH and OH + as a function of the available reservoir of H2. Methods. We obtained absorption spectra of the ground states of OH, OH+ and OI with high-velocity resolution, with GREAT on-board SOFIA, and with the THz receiver at the APEX. We analyzed them along with ancillary spectra of HF and CH from HIFI. To deconvolve them from the hyperfine structure and to separate the ble...

  13. Radioiodinated ganglioside G/sub M1/: A potential tracer for neurological studies

    Energy Technology Data Exchange (ETDEWEB)

    Zalutsky, M.R.; Gallagher, P.; Magistretti, P.L.; Ghidoni, R.

    1985-05-01

    Ganglioside G/sub M1/ is a glycosphingolipid which appears to be involved in the regeneration of damaged neuronal tissue. In addition, it is being investigated clinically in the treatment of various neuropathies. If labeled with the appropriate isotope, G/sub M1/ might be useful as a probe of these processes, particularly if it accumulates preferentially in cerebral infarcts. The G/sub M1/ -tyr derivative was labeled with I-125 in 75% yield using the Iodogen method and at micellar concentration was isolated using gel chromatography. Binding of I-125 (G/sub M1/ -tyr) to rat neuronal membranes was measured at concentrations of 5,50, and 500 nM. The amount bound (8,26, and 158 pmol/gm membrane) was similar to that reported for H-3(G/sub M1/). The biodistribution of I-125(G/sub M1/ -tyr) in mice at both micellar and monomeric concentrations was also similar to that of H-3(G/sub M1/). However, at monomeric concentrations, thyroid uptake of I-125 was about 10 times higher than at micellar concentrations, suggesting differential dehalogenation of the two forms. Initial studies in the gerbil stroke model suggest that the uptake of I-125(G/sub M1/ -tyr) in damaged brain is twice that in normal tissue.

  14. Nitrate retention and removal in Mediterranean streams with contrasting land uses: a 15N tracer study

    Directory of Open Access Journals (Sweden)

    J. L. Riera

    2008-08-01

    Full Text Available We used 15N-labelled nitrate (NO−3 additions to investigate nitrogen (N cycling at the whole-reach scale in three Mediterranean streams subjected to contrasting land uses (i.e. forested, urban and agricultural. Our aim was to examine: i the magnitude and relative importance of NO−3 retention (i.e. assimilatory uptake, and removal, (i.e. denitrification, ii the relative contribution of the different primary uptake compartments to NO−3 retention, and iii the regeneration, transformation and export pathways of the retained N. The concentration of NO−3 increased and that of dissolved oxygen (DO decreased from the forested to the agricultural stream, with intermediate values in the urban stream. Standing stocks of primary uptake compartments were similar among streams and dominated by detritus compartments (i.e. fine and coarse benthic organic matter. In agreement, metabolism was net heterotrophic in all streams, although the degree of heterotrophy increased from the forested to the agricultural stream. The NO−3 uptake length decreased along this gradient, whereas the NO−3 mass-transfer velocity and the areal NO−3 uptake rate were highest in the urban stream. Denitrification was not detectable in the forested stream, but accounted for 9% and 68% of total NO−3 uptake in the urban and the agricultural stream, respectively. The relative contribution of detritus compartments to NO−3 assimilatory uptake was highest in the forested and lowest in the agricultural stream. In all streams, the retained N was rapidly transferred to higher trophic levels and regenerated back to the water column. Due to a strong coupling between regeneration and nitrification, most retained N was exported from the experimental reaches in the form of NO−3. This study evidences fast N cycling in Mediterranean streams. Moreover, results indicate that permanent NO−3 removal via denitrification may be enhanced over temporary NO−3 retention via assimilatory

  15. Organotin persistence in contaminated marine sediments and porewaters: In situ degradation study using species-specific stable isotopic tracers

    Energy Technology Data Exchange (ETDEWEB)

    Furdek, Martina; Mikac, Nevenka [Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, Zagreb (Croatia); Bueno, Maite; Tessier, Emmanuel; Cavalheiro, Joana [Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l’Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l’Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9 (France); Monperrus, Mathilde, E-mail: mathilde.monperrus@univ-pau.fr [Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l’Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l’Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9 (France)

    2016-04-15

    Highlights: • Limiting step in OTC degradation in sediments is their desorption into porewater. • TBT persistence in contaminated sediments increases in sediments rich in organic matter. • DBT does not accumulate in sediments as degradation product of TBT. • TBT and DBT degradation in porewaters occurs with half-lives from 2.9 to 9.2 days. • PhTs degradation is slower than BuTs degradation in oxic porewaters. - Abstract: This paper provides a comprehensive study of the persistence of butyltins and phenyltins in contaminated marine sediments and presents the first data on their degradation potentials in porewaters. The study’s aim was to explain the different degradation efficiencies of organotin compounds (OTC) in contaminated sediments. The transformation processes of OTC in sediments and porewaters were investigated in a field experiment using species-specific, isotopically enriched organotin tracers. Sediment characteristics (organic carbon content and grain size) were determined to elucidate their influence on the degradation processes. The results of this study strongly suggest that a limiting step in OTC degradation in marine sediments is their desorption into porewaters because their degradation in porewaters occurs notably fast with half-lives of 9.2 days for tributyltin (TBT) in oxic porewaters and 2.9 ± 0.1 and 9.1 ± 0.9 days for dibutyltin (DBT) in oxic and anoxic porewaters, respectively. By controlling the desorption process, organic matter influences the TBT degradation efficiency and consequently defines its persistence in contaminated sediments, which thus increases in sediments rich in organic matter.

  16. Dye Aggregation in Ink Jet

    Institute of Scientific and Technical Information of China (English)

    Thomas Paul; Sarfraz Hussain

    2004-01-01

    Dye aggregation has long been recognised as a key factor in performance, and this is no less so in ink jet applications. The aggregation state was shown to be important in many different areas ranging from the use of dyes in photodynamic therapies all the way to colorants for dying of fabrics. Therefore different methods to investigate dye association qualitatively and quantitatively were developed. A simple procedure to study aggregation could be a useful tool to characterise dyes for ink jet printing. It is critically reviewed the methods used to study dye aggregation, and discussed some of the main conclusions. This will be illustrated by examples of ink jet dye aggregation and its study in aqueous and ink systems. The results are used to correlate the solution behaviour of dyes with their print performance.

  17. Studies of Dye Sensitisation Kinetics and Sorption Isotherms of Direct Red 23 on Titania

    Directory of Open Access Journals (Sweden)

    Peter J. Holliman

    2008-01-01

    Full Text Available Sorption kinetics and isotherms have been measured for a commercial dye (Direct Red 23 on different samples of powdered Titania, and the data were analysed to better understand the dye sensitization process for dye sensitised solar cells (DSSCs. For the sorption kinetics, the data show rapid initial sorption (<1 hour followed by slower rate of increasing uptake between 1 and 24 hours. While higher initial concentrations of dye correspond to higher sorption overall, less dye is absorbed from higher initial dye concentrations when considered as percentage uptake. The correlation between the sorption data and model isotherms has been considered with time. The Langmuir model shows better correlations compared to the Freundlich isotherm. The dye uptake data has also been correlated with Titania characterization data (X-ray diffraction, scanning electron microscopy, BET and zero point charge analysis. Kinetic data show significantly better fits to second-order models compared to first order. This suggests that chemisorption is taking place and that the interaction between the dye sorbate and the Titania sorbent involves electron sharing to form an ester bond.

  18. Equilibrium studies on sorption of an anionic dye onto acid activated ...

    African Journals Online (AJOL)

    ISHIOMA

    pollution, but dyes are visible even in small quantities due ... have been used for the removal of colour and metal ions ... In a world of rapid assimilation of natural resources, ... aqueous solution of this dye was prepared from stock solutions in.

  19. The Application of Tea Dyeing to Silk

    Institute of Scientific and Technical Information of China (English)

    金成嬉

    2001-01-01

    Vegetable dyes are eco-friendly throughout the full production process. A study is conducted with the purpose of assessing the properties of dye extracted from green tea, black tea and the tea tree cultivated and used in Jiang Nan area of China. The extracted dyes are applied with and without mordants on silk fabric and the dyeing properties are evaluated.

  20. Effect of ferromagnetic nanoparticle on dyes biodegradation

    OpenAIRE

    Apostol, Laura; Pereira, Luciana; Pereira, Raquel; Alves, M.M.; Gavrilescu, M.

    2011-01-01

    In this study the biodecolourisation of two dyes, a xanthene dye, Erythrosine B (Ery B) and an azo dye, Reactive Red 51 (RR120), was investigated colourdecolourisationunder batch anaerobic conditions by using non - acclimated anaerobic granular sludge. The effect of ferromagnetic nanoparticle (FN) (as adsorbent or mediator) on dyes removal was experienced.

  1. Factors Affecting the Performance of Champion Silyl-Anchor Carbazole Dye Revealed in the Femtosecond to Second Studies of Complete ADEKA-1 Sensitized Solar Cells.

    Science.gov (United States)

    Sobuś, Jan; Gierczyk, Błażej; Burdziński, Gotard; Jancelewicz, Mariusz; Polanski, Enrico; Hagfeldt, Anders; Ziółek, Marcin

    2016-10-24

    Record laboratory efficiencies of dye-sensitized solar cells have been recently reported using an alkoxysilyl-anchor dye, ADEKA-1 (over 14 %). In this work we use time-resolved techniques to study the impact of key preparation factors (dye synthesis route, addition of co-adsorbent, use of cobalt-based electrolytes of different redox potential, creation of insulating Al2 O3 layers and molecule capping passivation of the electrode) on the partial charge separation efficiencies in ADEKA-1 solar cells. We have observed that unwanted fast recombination of electrons from titania to the dye, probably associated with the orientation of the dyes on the titania surface, plays a crucial role in the performance of the cells. This recombination, taking place on the sub-ns and ns time scales, is suppressed in the optimized dye synthesis methods and upon addition of the co-adsorbent. Capping treatment significantly reduces the charge recombination between titania and electrolyte, improving the electron lifetime from tens of ms to hundreds of ms, or even to single seconds. Similar increase in electron lifetime is observed for homogenous Al2 O3 over-layers on titania nanoparticles, however, in this case the total solar cells photocurrent is decreased due to smaller electron injection yield from the dye. Our studies should be important for a broader use of very promising silyl-anchor dyes and the further optimization and development of dye-sensitized solar cells.

  2. Tracer attenuation in groundwater

    Science.gov (United States)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  3. Effects of low-dye taping on plantar pressure pre and post exercise: an exploratory study

    Directory of Open Access Journals (Sweden)

    Nolan Damien

    2009-04-01

    Full Text Available Abstract Background Low-Dye taping is used for excessive pronation at the subtalar joint of the foot. Previous research has focused on the tape's immediate effect on plantar pressure. Its effectiveness following exercise has not been investigated. Peak plantar pressure distribution provides an indirect representation of subtalar joint kinematics. The objectives of the study were 1 To determine the effects of Low-Dye taping on peak plantar pressure immediately post-application. 2 To determine whether any initial effects are maintained following exercise. Methods 12 asymptomatic subjects participated; each being screened for excessive pronation (navicular drop > 10 mm. Plantar pressure data was recorded, using the F-scan, at four intervals during the testing session: un-taped, baseline-taped, post-exercise session 1, and post-exercise session 2. Each exercise session consisted of a 10-minute walk at a normal pace. The foot was divided into 6 regions during data analysis. Repeated-measures analysis of variance (ANOVA was used to assess regional pressure variations across the four testing conditions. Results Reduced lateral forefoot peak plantar pressure was the only significant difference immediately post tape application (p = 0.039. This effect was lost after 10 minutes of exercise (p = 0.036. Each exercise session resulted in significantly higher medial forefoot peak pressure compared to un-taped; (p = 0.015 and (p = 0.014 respectively, and baseline-taped; (p = 0.036 and (p = 0.015 respectively. Medial and lateral rearfoot values had also increased after the second session (p = 0.004, following their non-significant reduction at baseline-taped. A trend towards a medial-to-lateral shift in pressure present in the midfoot immediately following tape application was still present after 20 minutes of exercise. Conclusion Low-Dye tape's initial effect of reduced lateral forefoot peak plantar pressure was lost after a 10-minute walk. However, the tape

  4. Effects of low-dye taping on plantar pressure pre and post exercise: an exploratory study.

    LENUS (Irish Health Repository)

    Nolan, Damien

    2009-01-01

    BACKGROUND: Low-Dye taping is used for excessive pronation at the subtalar joint of the foot. Previous research has focused on the tape\\'s immediate effect on plantar pressure. Its effectiveness following exercise has not been investigated. Peak plantar pressure distribution provides an indirect representation of subtalar joint kinematics. The objectives of the study were 1) To determine the effects of Low-Dye taping on peak plantar pressure immediately post-application. 2) To determine whether any initial effects are maintained following exercise. METHODS: 12 asymptomatic subjects participated; each being screened for excessive pronation (navicular drop > 10 mm). Plantar pressure data was recorded, using the F-scan, at four intervals during the testing session: un-taped, baseline-taped, post-exercise session 1, and post-exercise session 2. Each exercise session consisted of a 10-minute walk at a normal pace. The foot was divided into 6 regions during data analysis. Repeated-measures analysis of variance (ANOVA) was used to assess regional pressure variations across the four testing conditions. RESULTS: Reduced lateral forefoot peak plantar pressure was the only significant difference immediately post tape application (p = 0.039). This effect was lost after 10 minutes of exercise (p = 0.036). Each exercise session resulted in significantly higher medial forefoot peak pressure compared to un-taped; (p = 0.015) and (p = 0.014) respectively, and baseline-taped; (p = 0.036) and (p = 0.015) respectively. Medial and lateral rearfoot values had also increased after the second session (p = 0.004), following their non-significant reduction at baseline-taped. A trend towards a medial-to-lateral shift in pressure present in the midfoot immediately following tape application was still present after 20 minutes of exercise. CONCLUSION: Low-Dye tape\\'s initial effect of reduced lateral forefoot peak plantar pressure was lost after a 10-minute walk. However, the tape continued

  5. On the study of the Metal-complex Dye Polyurethane Ionomer

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ The reaction of toluene diisocyanate with polyester, dimethylol propionic acid, metal-complex dye and other additives to form the structure of metal-complex dye polyurethane ionomer molecule has been proven by FT-IR spectra. In aqueous solution, the surface tension of metal-complex dye polyurethane ionomer molecule is seen to slightly increase with increasing concentrtion of metal-complex dye and neopentyl glycol, respectively. This is because the adsorption of hydrophobics of ionomer molecules at the surface of aqueous solution becomes even more order. Under the same experimental condition, the surface tension of metal-complex dye polyurethane ionomer molecule in aqueous solution appears to slightly decrease with increasing NCO/OH ratio, as a result of increased hydrophobics of ionomer molecule adsorbed at the surface of aqueous solution.

  6. On the study of the Metal-complex Dye Polyurethane Ionomer

    Institute of Scientific and Technical Information of China (English)

    WANG; ChengLi

    2001-01-01

    The reaction of toluene diisocyanate with polyester, dimethylol propionic acid, metal-complex dye and other additives to form the structure of metal-complex dye polyurethane ionomer molecule has been proven by FT-IR spectra. In aqueous solution, the surface tension of metal-complex dye polyurethane ionomer molecule is seen to slightly increase with increasing concentrtion of metal-complex dye and neopentyl glycol, respectively. This is because the adsorption of hydrophobics of ionomer molecules at the surface of aqueous solution becomes even more order. Under the same experimental condition, the surface tension of metal-complex dye polyurethane ionomer molecule in aqueous solution appears to slightly decrease with increasing NCO/OH ratio, as a result of increased hydrophobics of ionomer molecule adsorbed at the surface of aqueous solution.  ……

  7. Study of Spatial and Temporal Processes of Soil Erosion on Sloping Land Using Rare Earth Elements As Tracers

    Institute of Scientific and Technical Information of China (English)

    薛亚洲; 刘普灵; 杨明义; 琚彤军

    2004-01-01

    Rare earth elements(REE) were used to study the temporal and spatial processes of soil erosion from different depths and sections of a slope. Two simulated rainfall events were applied to a prepared plot with a slope of 22°. The total runoff and sediment yield were collected every minute during the rainfall events. During the first twenty minutes of the first rainfall event,the average rate of rill erosion and the accumulated sediment yield due to rill erosion was 0.5 and 0.3 times higher than for sheet erosion. During this time,most of the erosion occurred on the lower one third of the plot. After 20 min,rill erosion became the dominant process on the slope. The average acceleration in the rate of rill erosion,the rate of rill erosion and the accumulated sediment yield due to rill erosion were 42,6 and 4 times higher than that of sheet erosion,respectively. During the first 35 minutes of the second rainfall event,the average acceleration in the rate of rill erosion was 6~9 times higher than that of sheet erosion. Afterwards,the slope became nearly stable with little change in either rill or sheet erosion rates. Initially,most of the rill erosion occurred in the lower third of the slope but later the preexisting rillhead in the middle section of the slope became reactivated and erosion in this section of the slope increased rapidly. These results indicate that REE tracer technology is a valuable tool for quantifying spatial and temporal changes in erosion from a soil slope.

  8. Laminar segregation of GABAergic neurons in the avian nucleus isthmi pars magnocellularis: a retrograde tracer and comparative study.

    Science.gov (United States)

    Faunes, Macarena; Fernández, Sara; Gutiérrez-Ibáñez, Cristián; Iwaniuk, Andrew N; Wylie, Douglas R; Mpodozis, Jorge; Karten, Harvey J; Marín, Gonzalo

    2013-06-01

    The isthmic complex is part of a visual midbrain circuit thought to be involved in stimulus selection and spatial attention. In birds, this circuit is composed of the nuclei isthmi pars magnocellularis (Imc), pars parvocellularis (Ipc), and pars semilunaris (SLu), all of them reciprocally connected to the ipsilateral optic tectum (TeO). The Imc conveys heterotopic inhibition to the TeO, Ipc, and SLu via widespread γ-aminobutyric acid (GABA)ergic axons that allow global competitive interactions among simultaneous sensory inputs. Anatomical studies in the chick have described a cytoarchitectonically uniform Imc nucleus containing two intermingled cell types: one projecting to the Ipc and SLu and the other to the TeO. Here we report that in passerine species, the Imc is segregated into an internal division displaying larger, sparsely distributed cells, and an external division displaying smaller, more densely packed cells. In vivo and in vitro injections of neural tracers in the TeO and the Ipc of the zebra finch demonstrated that neurons from the external and internal subdivisions project to the Ipc and the TeO, respectively, indicating that each Imc subdivision contains one of the two cell types hodologically defined in the chick. In an extensive survey across avian orders, we found that, in addition to passerines, only species of Piciformes and Rallidae exhibited a segregated Imc, whereas all other groups exhibited a uniform Imc. These results offer a comparative basis to investigate the functional role played by each Imc neural type in the competitive interactions mediated by this nucleus.

  9. Studies on application of annatto (Bixa orellena L.) dye formulations in dairy products.

    Science.gov (United States)

    Sathiya Mala, Kripanand; Prabhakara Rao, Pamidighantam; Prabhavathy, Manda Babu; Satyanarayana, Akula

    2015-02-01

    Annatto is often used to add color to dairy products such as butter, cheese, or puddings. In India usage of annatto is restricted to butter and cheese, however there are no tailor made formulations available to obtain standardized colour shades for the products. Hence a study was initiated to develop the appropriate annatto dye formulations and level of application in few dairy products (butter, cheese, paneer, biscuit cream, icing cream). Dye extracted from annatto seeds was used for the preparation of water soluble potassium carbonate formulation (nor-bixin, 11.24 %), oil soluble formulation (1.35 % bixin) and an oil/water soluble propylene glycol formulation (PG formulation, 1.31 % bixin). Lovibond tintometer colour units of the commercial butter, cheese and biscuit cream samples were measured for standardizing the colour concentration in the experimental products. The present study evaluates the application and stability of these formulations in butter, cheese, paneer, biscuit cream, icing cream. The products were evaluated for stability of colour and bixin during storage period. The oil/water soluble propylene glycol formulation was found to be tailor-made for all the dairy products studied though the standardized levels varied between 3.75 and 5.0 mg/kg for butter, 3.75 mg/kg for cheese, 5.0-400 mg/kg for biscuit cream, 12.25 and 25 mg/kg for paneer, 5.0-500 mg/kg for icing cream. Increasing concentration in the range of 30-500 mg/kg yielded products with light cream to orange shades, useful for decorating cakes. The average recovery of bixin from the products immediately after processing was 90-98 %. Significant changes (P ≤ 0.05) were noticed in the colour units and recovery of bixin in all the products during storage of 6 months.

  10. Comparative Studies of the Adsorption of Direct Dye on Activated Carbon and Conducting Polymer Composite

    Directory of Open Access Journals (Sweden)

    J. Raffiea Baseri

    2012-01-01

    Full Text Available This study analyses the feasibility of removing Direct Blue 71 from aqueous solution by different adsorbents such as activated carbon (TPAC and Poly pyrrole polymer composite (PPC prepared from Thevetia Peruviana. Batch mode adsorption was performed to investigate the adsorption capacities of these adsorbents by varying initial dye concentration, temperature, agitation time and pH. The performance of TPAC was compared with PPC. Among the adsorbents, PPC had more adsorption capacity (88.24% than TPAC (58.82% at an initial concentration of 50 mg/L and at 30°C. The experimental data best fitted with pseudo second order kinetic model. The adsorption data fitted well for Langmuir adsorption isotherm. Thermodynamic parameters for the adsorbents were also evaluated. The carbon embedded in conducting polymers matrix show better adsorptive properties than activated carbon.

  11. Imaging Studies of photodamage and self-healing in disperse orange 11 dye-doped PMMA

    CERN Document Server

    Anderson, Benjamin; Kuzyk, Mark G

    2011-01-01

    We report on optical imaging studies of self-healing after laser-induced photodamage in disperse orange 11 dye doped into poly(methyl methacrylate) (PMMA) polymer. In particular, the high spatial-contrast image of the damage track made by a line focus pump laser allows the recovery rates to be measured as a function of burn dose using the relationship between transverse distance and pump intensity profile. The time evolution of the damaged population results in an intensity-independent time constant of {\\tau} = 490\\pm23 min, in agreement with independent measurements of the time evolution of amplified spontaneous emission. Also observed is a damage threshold above which the material does not fully recover.

  12. Study on Carbon Nanocomposite Counterelectrode for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Yiming Chen

    2012-01-01

    Full Text Available Carbon nanocomposite electrodes were prepared by adding carbon nanotubes (CNTs into carbon black as counterelectrodes of dye-sensitized solar cells(DSSCs. The morphology and structure of carbon nanocomposite electrodes were studied by scanning electron microscopy. The influence of CNTs on the electrochemical performance of carbon nanocomposite electrodes is investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Carbon nano composite electrodes with CNTs exhibit a highly interconnected network structure with high electrical conductivity and good catalytic activity. The influence of different CNTs content in carbon nanocomposite electrodes on the open-circuit voltage, short-circuit current, and filling factor of DSSCs is also investigated. DSSCs with 10% CNTs content exhibit the best photovoltaic performance in our experiments.

  13. Gold nanoworms immobilized graphene oxide polymer brush nanohybrid for catalytic degradation studies of organic dyes

    Science.gov (United States)

    Mogha, Navin Kumar; Gosain, Saransh; Masram, Dhanraj T.

    2017-02-01

    In the present work, we report gold nanoparticles (AuNPs) on poly (dimethylaminoethyl methacrylate) (PDMAEMA) brushes immobilized reduced graphene oxide (Au/PDMAEMA/RGO) as catalyst for degradation kinetic studies of Rhodamine B (RB), Methyl Orange (MO) and Eosine Y (EY) dyes, having an excellent catalytic activity, as evident by the apparent rate constant (kapp), which is found to be 21.8, 26.2, and 8.7 (×10-3 s-1), for RB, MO and EY respectively. Au/PDMAEMA/RGO catalyst is easy to use, highly efficient, recyclable, which make it suitable for applications in waste water management. Foremost, synthesis of PDMAEMA brushes on graphene oxide is accomplished by Atom transfer radical polymerization method (ATRP), whereas AuNPs are synthesized by simple chemical reduction method.

  14. Mining-impacted sources of metal loading to an alpine stream based on a tracer-injection study, Clear Creek County, Colorado

    Science.gov (United States)

    Fey, David L.; Wirt, Laurie

    2007-01-01

    Base flow water in Leavenworth Creek, a tributary to South Clear Creek in Clear Creek County, Colorado, contains copper and zinc at levels toxic to aquatic life. The metals are predominantly derived from the historical Waldorf mine, and sources include an adit, a mine-waste dump, and mill-tailings deposits. Tracer-injection and water-chemistry synoptic studies were conducted during low-flow conditions to quantify metal loads of mining-impacted inflows and their relative contributions to nearby Leavenworth Creek. During the 2-year investigation, the adit was rerouted in an attempt to reduce metal loading to the stream. During the first year, a lithium-bromide tracer was injected continuously into the stream to achieve steady-state conditions prior to synoptic sampling. Synoptic samples were collected from Leavenworth Creek and from discrete surface inflows. One year later, synoptic sampling was repeated at selected sites to evaluate whether rerouting of the adit flow had improved water quality.

  15. Dual-tracer method to estimate coral reef response to a plume of chemically modified seawater

    Science.gov (United States)

    Maclaren, J. K.; Caldeira, K.

    2013-12-01

    We present a new method, based on measurement of seawater samples, to estimate the response of a reef ecosystem to a plume of an additive (for example, a nutrient or other chemical). In the natural environment, where there may be natural variability in concentrations, it can be difficult to distinguish between changes in concentrations that would occur naturally and changes in concentrations that result from a chemical addition. Furthermore, in the unconfined natural environment, chemically modified water can mix with waters that have not been modified, making it difficult to distinguish between effects of dilution and effects of chemical fluxes or transformations. We present a dual-tracer method that extracts signals from observations that may be affected by both natural variability and dilution. In this dual-tracer method, a substance (in our example case, alkalinity) is added to the water in known proportion to a passive conservative tracer (in our example case, Rhodamine WT dye). The resulting plume of seawater is allowed to flow over the study site. Two transects are drawn across the plume at the front and back of the study site. If, in our example, alkalinity is plotted as a function of dye concentration for the front transect, the slope of the resulting mixing line is the ratio of alkalinity to dye in the added fluid. If a similar mixing line is measured and calculated for the back transect, the slope of this mixing line will indicate the amount of added alkalinity that remains in the water flowing out of the study site per unit of added dye. The ratio of the front and back slopes indicates the fraction of added alkalinity that was taken up by the reef. The method is demonstrated in an experiment performed on One Tree Reef (Queensland, Australia) aimed at showing that ocean acidification is already affecting coral reef growth. In an effort to chemically reverse some of the changes to seawater chemistry that have occurred over the past 200 years, we added

  16. OPTIMIZATION OF DYEING PARAMETERS TO DYE COTTON WITH CARROT EXTRACTION

    Directory of Open Access Journals (Sweden)

    MIRALLES Verónica

    2017-05-01

    Full Text Available Natural dyes derived from flora and fauna are believed to be safe because of non-toxic, non-carcinogenic and biodegradable nature. Furthermore, natural dyes do not cause pollution and waste water problems. Natural dyes as well as synthetic dyes need the optimum parameters to get a good dyeing. On some occasions, It is necessary the use of mordants to increase the affinity between cellulose fiber and natural dye, but there are other conditions to optimize in the dyeing process, like time, temperature, auxiliary porducts, etc. In addition, the optimum conditions are different depends on the type of dye and the fiber nature. The aim of this work is the use of carrot extract to dye cotton fabric by exhaustion at diverse dyeing conditions. Diffferent dyeing processes were carried out to study the effect of pH condition and the temperature, using 7, 6 and 4 pH values and 95 ºC and 130ºC for an hour. As a result some images of dyed samples are shown. Moreover, to evaluate the colour of each sample CIELAB parameters are analysed obtained by reflexion spectrophotometre. The results showed that the temperature used has an important influence on the colour of the dyed sample.

  17. Chitosan beads as barriers to the transport of azo dye in soil column.

    Science.gov (United States)

    Lazaridis, Nikolaos K; Keenan, Helen

    2010-01-15

    The development of chitosan-based materials as useful adsorbent polymeric matrices is an expanding field in the area of adsorption science. Although chitosan has been successfully used for the removal of dyes from aqueous solutions, no consideration is given to the removal of dyes from contaminated soils. Therefore this study focuses on the potential use of chitosan as an in situ remediation technology. The chitosan beads were used as barriers to the transport of a reactive dye (Reactive Black 5, RB5) in soil column experiments. Batch sorption experiments, kinetic and equilibrium, were performed to estimate the sorption behavior of both chitosan and soil. The chitosan beads were prepared in accordance with published literature and a synthetic soil was prepared by mixing quantities of sand, silt and clay. The synthetic soil was classified according to British Standards. Calcium chloride was used as tracer to define transport rates and other physical experimental parameters. Dye transport reaction parameters were determined by fitting dye breakthrough curves (BTCs) to the HYDRUS-1D version 4.xx software. Fourier Transform-Infra Red (FT-IR) spectroscopy was used to reveal the sorption mechanism. The study showed that chitosan exhibited a high sorption capacity (S(max)=238 mg/g) and pseudo-first sorption rate (k(1)=1.02 h(-1)) coupled with low swelling and increased retardation for the azo dye tested. Thus it has potential as a Permeable Reactive Barrier (PRB) for containment and remediation of contaminated sites.

  18. Studies on the preparation of low-carrier Se-73,75 tracers for in vivo examinations; Untersuchungen zur Darstellung traegerarm 73,75Se-markierter Tracer fuer in vivo Untersuchungen

    Energy Technology Data Exchange (ETDEWEB)

    Helfer, Andreas

    2013-04-03

    studies with respect to tracer application with PET. First in vitro distributions studies with slices of rat brain were already performed by autoradiography.

  19. Theoretical study of fluorescence resonant energy transfer dynamics in individual semiconductor nanocrystal-DNA-dye conjugates

    Energy Technology Data Exchange (ETDEWEB)

    Shan Guangcun [Department of Physics and Materials Science, City University of Hong Kong (Hong Kong); Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, Nanjing 210003 (China); Bao Shuying, E-mail: spinor@163.com [Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, Nanjing 210003 (China) and Department of Physics, Fudan University, Handan Road, Shanghai 200433 (China); Shek, Chan-Hung [Department of Physics and Materials Science, City University of Hong Kong (Hong Kong); Huang Wei [Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, Nanjing 210003 (China)

    2012-06-15

    Motivated by recent experimental studies of fluorescence resonant energy transfer (FRET), we consider the influence of the temperature-dependent microscopic spectral overlap and relative orientation of the transition dipoles of fluorophores on the nanosecond dynamics of photon statistics and energy transfer efficiency in semiconductor nanocrystal-DNA-organic dye conjugates using Monte-Carlo simulations. Our calculated mean energy transfer efficiencies are found to be well consistent with those measured in experiment at low temperatures. For the higher temperatures, our results demonstrate that the use of Foerster radius estimated from the isotropic dynamic average value of 2/3 for the orientation parameter term may lead to overestimation of energy transfer efficiency for the cases of the rigid arrangement of fluorophore transition moments, and thereby deteriorate the precision of the analysis of donor-acceptor distances. Our theoretical results here underline the importance of a detailed understanding of the microscopic picture of FRET for exploiting this spectroscopic technique in various nano- and bio-applications. - Graphical abstract: The temperature-dependent fluorescence resonant energy transfer dynamics in individual semiconductor nanocrystal-DNA-dye conjugates is modeled by a master equation for the density matrix operator and solved by Monte Carlo simulation. Highlights: Black-Right-Pointing-Pointer The energy transfer dynamics is modeled by a density matrix master equation. Black-Right-Pointing-Pointer The dynamics in individual conjugates is investigated by Monte Carlo simulation. Black-Right-Pointing-Pointer The dynamics is modeled within the context of microscopic spectral overlap theory. Black-Right-Pointing-Pointer Our work pave new way for developing FRET-based biotechnology.

  20. The Fischa-Dagnitz spring, Southern Vienna Basin: a multi tracer time series study re-assessing earlier conceptual assumptions.

    Science.gov (United States)

    Suckow, Axel; Gerber, Christoph; Kralik, Martin; Sültenfuss, Jürgen; Purtschert, Roland

    2013-04-01

    The gravel aquifer of the Southern Vienna Basin is a very important backup drinking water resource for the city of Vienna. A discharge location, the Fischa-Dagnitz spring in the Southern Vienna Basin, Austria, was re-investigated in 2011, five years after the gas exchange tracer test published in (Stolp et al., 2010), and sampled for stable isotopes 18O/2H, tritium, 3He, SF6 and 85Kr (Gerber et al., 2012). Additionally, new tritium time series data (Davis et al., 1967), previously not considered in Stolp et al. (2010), were included. These show a higher and earlier tritium peak of >300 TU in 1965 in the discharge of the Fischa-Dagnitz spring as compared to 221 TU in 1972 considered in Stolp et al. (2010). The new 3He, SF6 and 85Kr gas tracer data from 2011 confirm the earlier finding for 3He of Stolp et al. (2010) and indicate a more recent equilibration with the atmosphere than the water bound tracers 18O, 2H and tritium. A new modelling attempt using the Lumpy code (Suckow, 2012) confirmed the discrepancy between the tritium data and the gaseous tracers 3He, SF6 and 85Kr. No steady-state combination of local recharge (represented by an exponential model) and Schwarza river infiltration flowing through the gravel aquifer (represented by a parallel dispersion model) can equally well explain both the tritium time series and the gas tracer results. A revised conceptual model proposes that a pinching of the aquifer at unconformities in the gravel body or a fault zone known in the gravel body forces groundwater along the flow path closer to the surface and exposes it to the atmosphere. This would tend to reset the "dating" clock for the gaseous tracers 3He, SF6 and 85Kr, which can equilibrate quickly with the atmosphere, but not for tritium, which marks the transport behaviour of the water itself. These findings are of importance also for other multi-tracer assessments of groundwater movement in phreatic aquifer systems. References: Davis, G.H., Payne, B.R., Dincer, T

  1. DFT Study of the Structure, Reactivity, Natural Bond OrbitalandHyperpolarizabilityofThiazoleAzoDyes

    Directory of Open Access Journals (Sweden)

    Osman I. Osman

    2017-02-01

    Full Text Available The structure, reactivity, natural bond orbital (NBO, linear and nonlinear optical (NLO properties of three thiazole azo dyes (A, B and C were monitored by applying B3LYP, CAM-B3LYP and ωB97XD functionals with 6-311++G** and aug-cc-pvdz basis sets. The geometrical parameters,dipolemoments,HOMO-LUMO(highestoccupiedmolecularorbital,lowestunoccupied molecular orbital energy gaps, absorption wavelengths and total hyperpolarizabilities were investigated in carbon tetrachloride (CCl4 chloroform (CHCl3, dichloromethane (CH2Cl2 and dimethlysulphoxide (DMSO. The donor methoxyphenyl group deviates from planarity with the thiazole azo moiety by ca. 38◦; while the acceptor dicyanovinyl, indandione and dicyanovinylindanone groups diverge by ca. 6◦. The HOMOs for the three dyes are identical. They spread over the methoxyphenyl donor moiety, the thiazole and benzene rings as π-bonding orbitals. The LUMOs are shaped up by the nature of the acceptor moieties. The LUMOs of the A, B and C dyes extend over the indandione, malononitrile and dicyanovinylindanone acceptor moieties, respectively, as π-antibonding orbitals. The HOMO-LUMO splittings showed that Dye C is much more reactive than dyes A and B. Compared to dyes A and B, Dye C yielded a longer maximum absorption wavelength because of the stabilization of its LUMOs relative to those of the other two. The three dyes show solvatochromism accompanied by significant increases in hyperpolarizability. The enhancement of the total hyperpolarizability of C compared to those of AandBisduetothecumulativeactionofthelongπ-conjugationoftheindanoneringandthestronger electron-withdrawingabilityofthedicyanovinylmoietythatformthedicyanovinylindanoneacceptor group. These findings are facilitated by a natural bond orbital (NBO technique. The very high total hyperpolarizabilities of the three dyes define their potent nonlinear optical (NLO behaviour.

  2. Estimation of migration characteristics of a nonsorbing tracer through an artificial rock fracture

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, B. H.; Park, J. K.; Han, P. S. [KAERI, Taejon (Korea, Republic of)

    1998-10-01

    Experiment on the transport of a nonsorbing tracer in an artificial rock fracture was carried out. The scale of an artificial rock was 50x20x5cm. The migration field was assumed as a two dimensional system. Eosine, a kind of an organic dye, was used as a nonsorbing tracer. This tracer was injected as a pulse function in a point source and point withdraw system. Volumetric flow rate was 0.5ml/min. The migration plume of the tracer was captured by a digital camera and compared with a result from transport modeling.

  3. Nitrogen metabolism as effect parameter for air pollution in plant bioindicators - a {sup 15}N-tracer study

    Energy Technology Data Exchange (ETDEWEB)

    Hafner, C.; Jung, K.; Schueuermann, G. [UFZ - Umweltforschungszentrum, Leipzig (Germany). Sektion Chemische Oekotoxikologie; Kostka-Rick, R. [Biologisch Ueberwachen und Bewerten, Echterdingen (Germany); Hahn, H.U. [DaimlerChrysler AG, Sindelfingen (Germany)

    2002-07-01

    Since many years, bioindicator plants have been used for effect monitoring of air pollution. In this paper it is demonstrated that the determination of the nitrogen metabolism activity of plants using stable isotope tracer techniques has proven a suitable method for detecting sublethal effects of multiple, low-dose and chronic pollution load. This method permits to diagnose air pollution on a metabolic level of an early stage before visible damages on plants occur. (orig.)

  4. Simultaneous studies on solar energy storage by CO2 reduction to HCOOH with Brilliant Green dye removal photoelectrochemically

    Directory of Open Access Journals (Sweden)

    V.S.K. Yadav

    2016-12-01

    Full Text Available The simultaneous study on photoelectrochemical CO2 reduction with Brilliant Green (BG dye removal was studied in the present work. Experimental studies were done in aqueous solutions of sodium and potassium based electrolytes using a cathode [Zinc (Zn and Tin (Sn] and a common cobalt oxide (Co3O4 anode electrocatalyst. The influence of reaction with electrolyte concentration for the both catalysts was shown clearly with respect to time. The selected electrocatalysts were able to reduce CO2 to formic acid (HCOOH along with high BG dye removal. With Sn as cathode, the maximum BG dye removal was obtained to be KHCO3–[95.9% (10 min–0.2 M], NaHCO3–[98.6% (15 min–0.6 M]. Similarly for Zn, KHCO3–[99.8% (10 min–0.4 M], NaHCO3–[99.9% (20 min–0.8 M] were observed respectively. Finally, the results have proven that higher efficiencies for BG dye removal were obtained along with HCOOH formation, which might be a better alternate for water purification and to decrease the atmospheric CO2 concentrations.

  5. Removal of reactive blue 19 dyes from textile wastewater by pomegranate seed powder: Isotherm and kinetic studies

    Directory of Open Access Journals (Sweden)

    Mahboobeh Dehvari

    2016-01-01

    Full Text Available Aims: The aim of this study was the evaluation of adsorption kinetics and equilibrium of reactive blue 19 dyes from textile synthetic wastewater by pomegranate seed powder. Materials and Methods: This study is an experimental research, which was performed in laboratory scale. In this study, the parameters such as adsorbent dose, pH and retention time, initial concentration of dye and agitation rate have been investigated. After washing and boiling of pomegranate seeds for 2 h, they dried, milled and finally pulverized by standard ASTM sieves (40-100 mesh. Maximum adsorption wave length (λmax by spectrophotometer ultra violet/visible (model SP-3000 Plus 592 nm was determined. The Langmuir, Freundlich and Temkin isotherm models and the pseudo-first-order and pseudo-second-order kinetic models were analyzed. Results: According to results, the removal efficiency with adsorbent dose, retention time and agitation rate has a direct relation. Maximum adsorption occurred in the first 60 min. The removal efficiency with initial concentration of dye and pH of solution has indirect relation. The Freundlich isotherm fits the experimental data better than the other isotherms. It was recognized that the adsorption followed by pseudo-second-order model (R2 > 0.99. Conclusion: Based on the results, pomegranate seeds as a new natural sorbent can be used in removal of dye and other environmental pollutants with desirable absorption capacity.

  6. Methodology Measuring Rare Earth Elements in High TDS Reservoir Brines Application as Natural Tracers in CCUS Studies

    Science.gov (United States)

    Smith, W.; Mcling, T. L.; Smith, R. W.; Neupane, H.

    2013-12-01

    In recent years rare earth elements (REE) have been demonstrated to be useful natural tracers for geochemical processes in aqueous environments. The application of REE's to carbon dioxide utilization and storage (CCUS) could provide researchers with a sensitive, inexpensive tool for tracking the movement of CO2 and displaced formation brines. By definition, geologic reservoirs that have been deemed suitable for carbon capture and storage contain formation brine with total dissolved solids (TDS) greater than 10,000 ppm and often these formation brines exceed 75,000 ppm TDS. This high TDS water makes it very difficult to measure REE, which typically occur at part per trillion concentrations. Critical to the use of REE for CCUS studies is the development of a procedure, which allows for the pre-concentration of REE's across a wide range of water quality. Additionally, due to the large number of samples that will need analysis, any developed procedure must be inexpensive, reproducible, and quick to implement. As part of the Big Sky Carbon Sequestration Project the INL's Center for Advance Energy Studies is developing REE pre-concentration procedures based on methods reported in the literature. While there are many REE pre-concentration procedures in the literature, our tests have shown these methods have difficulty at TDS greater than seawater (roughly 35,000 ppm TDS). Therefore, the ability to quantitatively measure REE's in formation brines with very high TDS has required the modification of an already developed procedure. After careful consideration and testing we selected methods modified after those described by Kingston et al., 1978 and Strachan et al., 1989 utilizing chelating media for very high TDS waters and ion-exchange media as detailed by Crock et al., 1984; Robinson et al., 1985; and Stetzenbach et al., 1994 for low TDS (<10,000 ppm TDS) waters. These modified procedures have been successfully tested in our laboratory and have proven effective in greatly

  7. Simultaneous dyeing and antibacterial finishing for cotton cellulose using a new reactive dye.

    Science.gov (United States)

    Farouk, R; Gaffer, H E

    2013-08-14

    Simultaneous dyeing and antibacterial finishing for cotton fabric using a new antibacterial reactive dye having a modified chemical structure to the commercial reactive dye CI Reactive Red 198 were studied. This modification was carried out by replacing metanilic acid in the commercial dye with 4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (sulfadimidine). Optimum exhaustion and fixation values were achieved at 60 g/l sodium sulphate and 20 g/l sodium carbonate for both dyes. The modified dye exhibited higher substantivity, exhaustion and fixation efficiency compared to the commercial dye. Antibacterial activities of the dyed samples at different concentrations of both dyes were studied against gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria. The cotton dyed with the modified dye shows higher antibacterial efficacy compared to the dyed cotton fabric using the commercial dye, especially on gram negative (E. coli) bacteria. All the reactive dyeings also exhibited high fastness properties.

  8. Studies on the Inhalation Toxicity of Dyes Present in Colored Smoke Munitions. Phase III, Studies: Four-Week Inhalation Exposures of Rats to Dye Aerosols.

    Science.gov (United States)

    1984-09-10

    response in rats exposed to the highest concentration (Table 21). The elevation in cytoplasmic enzymes in SAL (lactate dehydrogenase (L0H), glutathion ...reductase, and glutathione Speroxidase) indicates the SY/SG dye mixture caused some cell damage. The * Increased activity of the lysosomal enzyme, p...a renal infarct, and testicular atrophy. In brief, a mild exposure-related lesion was observed around the terminal airways in the lungs of all rats

  9. {sup 99m}TcO(BAT-NI), a novel nitroimidazole tracer: in vivo uptake studies in ischaemic myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Hoffend, J.; Linke, G.; Mohammed, A.; Haberkorn, U. [Department of Radiology, Division of Nuclear Medicine, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg (Germany); Tiefenbacher, C.P. [Department of Internal Medicine, Division of Cardiology, University of Heidelberg, Heidelberg (Germany); Eisenhut, M. [German Cancer Research Centre, Heidelberg (Germany)

    2003-04-01

    Myocardial perfusion single-photon emission tomography (SPET) performed with cationic technetium-99m complexes indicates ischaemic areas as cold lesions. By contrast, nitroimidazole derivatives labelled with fluorine-18 or {sup 99m}Tc have recently shown promising results for hot spot imaging of ischaemic myocardium. This study evaluates {sup 99m}TcO(BAT-NI), a new {sup 99m}Tc complex comprising the nitroimidazole ligand, 2,10-dimercapto-2,10-dimethyl-4,8-diaza-6-[4-(2-nitroimidazolyl)butyl]undecane, in a low-flow in vivo model of myocardial ischaemia in thoracotomised rats. To elucidate the influence of the 2-nitroimidazole group on ischaemia-induced uptake, comparisons with ligand derivatives were performed where (a) the 2-nitro group was deleted [{sup 99m}TcO(BAT-I)], (b) the 2-nitroimidazole functionality was replaced by a Br atom [{sup 99m}TcO(BAT-Br)] and (c) the {sup 99m}TcO(BAT) moiety was replaced by an iodine-125 iodophenoxybutyl ligand ({sup 125}IP-NI). The radiolabelled compounds were i.v. injected 15 min after reducing resting myocardial blood flow by 50-60% and the uptake of radioactivity was assessed 90 min post injection. Autoradiography of left ventricular short-axis slices showed median uptake ratios of ischaemic/non-ischaemic myocardium (I/N) of 3.4, 4.5 and 3.4 for {sup 99m}TcO(BAT-NI), {sup 99m}TcO(BAT-I) and {sup 99m}TcO(BAT-Br), respectively. In contrast, {sup 125}IP-NI was not preferentially taken up by ischaemic myocardium. Accumulation of {sup 99m}TcO(BAT-NI) in ischaemic heart regions was comparable to that in the liver. Biodistribution studies showed a median uptake of 0.65% ID/g of {sup 99m}TcO(BAT-NI) in ischaemic tissue and an I/N of 3.3. On planar images of the thorax and upper abdomen the ischaemic hearts were visualised faintly; the median heart to lung count ratio for {sup 99m}TcO(BAT-NI) was 1.7, and the median heart to liver count ratio was 1.0. We conclude that uptake of {sup 99m}TcO(BAT-NI) in ischaemic myocardium does not

  10. Sequence-selective binding of phenazinium dyes phenosafranin and safranin O to guanine-cytosine deoxyribopolynucleotides: spectroscopic and thermodynamic studies.

    Science.gov (United States)

    Saha, Ishita; Hossain, Maidul; Suresh Kumar, Gopinatha

    2010-11-25

    The sequence selectivity of the DNA binding of the phenazinium dyes phenosafranin and safranin O have been investigated with four sequence-specific deoxyribopolynucleotides from spectroscopic and calorimetric studies. The alternating guanine-cytosine sequence selectivity of the dyes has been revealed from binding affinity values, circular dichroism, thermal melting, competition dialysis, and calorimetric results. The binding affinities of both the dyes to the polynucleotides were of the order of 10(5) M(-1), but the values were higher for the guanine-cytosine polynucleotides over adenine-thymine ones. Phenosafranin had a higher binding affinity compared to safranin O. Isothermal titration calorimetric studies revealed that the binding reactions were exothermic and favored by negative enthalpy and predominantly large positive entropy contributions in all cases except poly(dA)·poly(dT) where the profile was anomalous. Although charged, nonpolyelectrolytic contribution was revealed to be dominant to the free energy of binding. The negative heat capacity values obtained from the temperature dependence of enthalpy changes, which were higher for phenosafranin compared to safranin O, suggested significant hydrophobic contribution to the binding process. In aggregate, the data presents evidence for the alternating guanine-cytosine base pair selectivity of these phenazinium dyes and a stronger binding of phenosafranin over safranin O.

  11. An optimized assay of specific IgE antibodies to reactive dyes and studies of immunologic responses in exposed workers.

    Science.gov (United States)

    Wass, U; Nilsson, R; Nordlinder, R; Belin, L

    1990-03-01

    Methods of assaying reactive dye-specific IgE antibodies were investigated with a RAST. Sera from three patients, occupationally exposed to a reactive dye, Remazol black B (Chemical Abstract registry number 17095-24-8), were used. Directly dyed disks, that is, disks without any carrier protein, resulted in poor and unreliable measures of specific IgE. In contrast, optimized preparation of conjugates between the dye and human serum albumin resulted in efficient binding of specific IgE. The patients' RAST results were strongly positive, whereas sera from 36 exposed workers but without symptoms and sera from unexposed subjects with high levels of total IgE were negative. The hapten and carrier specificity of the IgE antibodies was studied by direct RAST and RAST inhibition. In one patient, the antibodies were principally hapten specific, whereas another patient was found to have antibodies with a high degree of specificity to the carrier. The third patient's antibodies were intermediate between the other two patients' antibodies in this respect, suggesting that antibody specificity is dependent not only on the nature of the hapten but also on individual immune response factors. The study demonstrates that it is important to use an optimized preparation of dye-protein conjugates to elicit reliable results and a high degree of specific IgE binding in the RAST.

  12. A Comparative Study on Equilibrium Adsorption of Dyes on Adsorbents Prepared from Coastal Plant, C. equisetifolia Seeds via Green Modification and Activated Carbon

    Directory of Open Access Journals (Sweden)

    Jaafar Jazulhafiz Jefri

    2016-01-01

    Full Text Available Eco-friendly adsorbents were prepared from coastal plant, C. equisetifolia seeds treated with β-cyclodextrin (Rhusorbent for the removal of dyes. The study was carried out to determine the effectiveness of Rhusorbent to remove common dyes such as malachite green (MG and neutral red (NR dyes from aqueous solutions in batch experiments. The commercial activated carbon (AC was also used in this equilibrium absorption study which includes the effect of adsorbent dosage, initial dye concentration and contact time. The percentage of MG dye removal of about 92.4% and 88.4% was achieved for both Rhusorbent and AC respectively at concentration of 60mg/L and 0.4g absorbent. The equilibrium adsorption of about 91.1% and 79.1% was achieved for both Rhusorbent and AC respectively involving NR dye. The scanning electron micrographs of Rhusorbent show uneven and rough surface prompting evidence for the effective adsorption of MG and NR dyes on the surface of adsorbents. For both adsorption studies, Langmuir and Freundlich isotherm models fitted well the adsorption data involving both Rhusorbent and AC. C. equisetifolia seeds are a potential source for bio-inspired adsorbents for the removal of MG and NR dyes.

  13. Evaluation of leakage from fume hoods using tracer gas, tracer nanoparticles and nanopowder handling test methodologies.

    Science.gov (United States)

    Dunn, Kevin H; Tsai, Candace Su-Jung; Woskie, Susan R; Bennett, James S; Garcia, Alberto; Ellenbecker, Michael J

    2014-01-01

    The most commonly reported control used to minimize workplace exposures to nanomaterials is the chemical fume hood. Studies have shown, however, that significant releases of nanoparticles can occur when materials are handled inside fume hoods. This study evaluated the performance of a new commercially available nano fume hood using three different test protocols. Tracer gas, tracer nanoparticle, and nanopowder handling protocols were used to evaluate the hood. A static test procedure using tracer gas (sulfur hexafluoride) and nanoparticles as well as an active test using an operator handling nanoalumina were conducted. A commercially available particle generator was used to produce sodium chloride tracer nanoparticles. Containment effectiveness was evaluated by sampling both in the breathing zone (BZ) of a mannequin and operator as well as across the hood opening. These containment tests were conducted across a range of hood face velocities (60, 80, and 100 ft/min) and with the room ventilation system turned off and on. For the tracer gas and tracer nanoparticle tests, leakage was much more prominent on the left side of the hood (closest to the room supply air diffuser) although some leakage was noted on the right side and in the BZ sample locations. During the tracer gas and tracer nanoparticle tests, leakage was primarily noted when the room air conditioner was on for both the low and medium hood exhaust airflows. When the room air conditioner was turned off, the static tracer gas tests showed good containment across most test conditions. The tracer gas and nanoparticle test results were well correlated showing hood leakage under the same conditions and at the same sample locations. The impact of a room air conditioner was demonstrated with containment being adversely impacted during the use of room air ventilation. The tracer nanoparticle approach is a simple method requiring minimal setup and instrumentation. However, the method requires the reduction in

  14. Nonlinear optical properties of natural laccaic acid dye studied using Z-scan technique

    CSIR Research Space (South Africa)

    Zongo, S

    2015-08-01

    Full Text Available We have investigated the nonlinear optical properties, including the optical limiting behaviour for five different concentrations of laccaic acid dye in solution and a thin film obtained through doping in poly (methyl methacrylate) (PMMA) polymer...

  15. Study on time-resolved fluorescence dynamics of cyanine dye sensitizing AgBr

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The fluorescence spectra of three different dyes adsorbed on the tabular and cubic AgBr microcrystals are obtained by the picosecond time-resolved streak camera technique. The dependence of the ultrafast electron transferring from dye-aggre-gates to the conduction band of AgBr and the efficiency of spectral sensitization on different kinds of dyes with different concentrations is analyzed. Further more,the microcosmic mechanism of the sensitization process is discussed. It is found that the fluorescence decay curves are fitted very well by the double exponential func-tion,consisting of a slow component and a fast one with large amplitude. We con-sider this fast one mainly attributable to the electron transfer from dye J-aggre-gates to the conduction band of AgBr.

  16. Asian Tracer Experiment and Atmospheric Modeling (TEAM) Project: Draft Field Work Plan for the Asian Long-Range Tracer Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Allwine, K Jerry; Flaherty, Julia E.

    2007-08-01

    This report provides an experimental plan for a proposed Asian long-range tracer study as part of the international Tracer Experiment and Atmospheric Modeling (TEAM) Project. The TEAM partners are China, Japan, South Korea and the United States. Optimal times of year to conduct the study, meteorological measurements needed, proposed tracer release locations, proposed tracer sampling locations and the proposed durations of tracer releases and subsequent sampling are given. Also given are the activities necessary to prepare for the study and the schedule for completing the preparation activities leading to conducting the actual field operations. This report is intended to provide the TEAM members with the information necessary for planning and conducting the Asian long-range tracer study. The experimental plan is proposed, at this time, to describe the efforts necessary to conduct the Asian long-range tracer study, and the plan will undoubtedly be revised and refined as the planning goes forward over the next year.

  17. Study of Modern Nano Enhanced Techniques for Removal of Dyes and Metals

    OpenAIRE

    Samavia Batool; Shatirah Akib; Mushtaq Ahmad; Balkhair, Khaled S.; Muhammad Aqeel Ashraf

    2014-01-01

    Industrial effluent often contains the significant amount of hexavalent chromium and synthetic dyes. The discharge of wastewater without proper treatment into water streams consequently enters the soil and disturbs the aquatic and terrestrial life. A range of wastewater treatment technologies have been proposed which can efficiently reduce both Cr(VI) and azo dyes simultaneously to less toxic form such as biodegradation, biosorption, adsorption, bioaccumulation, and nanotechnology. Rate of si...

  18. Study on the judgment model of dyeing and weaving corporation's core competence

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    On the basis of the dyeing and weaving corporations' characters, this paper put forward the dimensionality and index system to analyze the core competence. This paper divided the core competence into three layers and gave out the Dimensional-Hierarchical structure of core competence through combining the analysis dimensionalities with the competence layers. The model was described to evaluate, analyze and judge the dyeing and weaving corporation's competence.

  19. Sequential anaerobic-aerobic biological treatment of colored wastewaters: case study of a textile dyeing factory wastewater.

    Science.gov (United States)

    Abiri, Fardin; Fallah, Narges; Bonakdarpour, Babak

    2017-03-01

    In the present study the feasibility of the use of a bacterial batch sequential anaerobic-aerobic process, in which activated sludge was used in both parts of the process, for pretreatment of wastewater generated by a textile dyeing factory has been considered. Activated sludge used in the process was obtained from a municipal wastewater treatment plant and adapted to real dyeing wastewater using either an anaerobic-only or an anaerobic-aerobic process over a period of 90 days. The use of activated sludge adapted using the anaerobic-aerobic process resulted in a higher overall decolorization efficiency compared to that achieved with activated sludge adapted using the anaerobic-only cycles. Anaerobic and aerobic periods of around 34 and 22 hours respectively resulted in an effluent with chemical oxygen demand (COD) and color content which met the standards for discharge into the centralized wastewater treatment plant of the industrial estate in which the dyeing factory was situated. Neutralization of the real dyeing wastewater and addition of carbon source to it, both of which results in significant increase in the cost of the bacterial treatment process, was not found to be necessary to achieve the required discharge standards.

  20. Influence of caries detection dye on bond strength of sound and carious affected dentin: An in-vitro study.

    Science.gov (United States)

    Singh, Udai Pratp; Tikku, Ap; Chandra, Anil; Loomba, Kapil; Boruah, Lalit Chandra

    2011-01-01

    The objective of this study was to evaluate the influence of caries detection dye on the in-vitro tensile bond strength of adhesive materials to sound and carious affected dentin. Forty healthy and carious human molars were ground to expose superficial sound dentin and carious affected dentin. Caries Detector dye was applied to sound and carious affected dentin and rinsed. Subsequently the dentin was etched with 37% phosphoric acid and rinsed leaving a moist dentin surface. The adhesive (Single bond) was applied in single layers and light cured. A posterior composite (Filtek Z 250) were used to prepare the bond strength specimens with a 3 mm in diameter bonding area. Control and experimental groups were made with and without application of dye respectively. Each group includes both sound and carious affected dentin. After 24 hour immersion in distilled water, tensile bond strength (MPa) was measured using an Instron testing machine. Analysis of variance (ANOVA) was used to evaluate the data. The tensile bond strength were significantly less in experimental subgroup than control subgroups. The tensile bond strengths were higher in sound and carious affected dentin without application of caries detection dyes.

  1. 氨纶纤维分散染料染色性能探讨%Studies on the Dyeing Behaviors of Disperse Dyes for Polyurethane Fibers

    Institute of Scientific and Technical Information of China (English)

    杜鹃; 王惠珍; 唐人成; 陈前兵; 申勇

    2001-01-01

    通过对几种结构类型分散染料氨纶纤维上染率的测定,结合分散染料的IOB(无机/有机)值,探讨了分散染料结构与氨纶染色性的关系,系统测试了影响分散染料染氨纶的主要工艺参数,提出氨纶染色优化工艺条件。%The relationship between the structures of disperse dyes andtheir dyeing behaviors is investigated bu determination the exhaustion rate of disperse dyes with different chemical structures for polyurethane fibers and their IOB values(Inorganic/Organic Balance).After the main process parameters affecting the dyeing behavior are tested systematically,the optimal process condition is put forward.

  2. Parametric and kinetic study of adsorptive removal of dyes from aqueous solutions using an agriculture waste

    Science.gov (United States)

    Bencheikh, imane; el hajjaji, souad; abourouh, imane; Kitane, Said; Dahchour, Abdelmalek; El M'Rabet, Mohammadine

    2017-04-01

    Wastewater treatment is the subject of several studies through decades. Interest is continuously oriented to provide cheaper and efficient methods of treatment. Several methods of treatment exit including coagulation flocculation, filtration, precipitation, ozonation, ion exchange, reverse osmosis, advanced oxidation process. The use of these methods proved limited because of their high investment and operational cost. Adsorption can be an efficient low-cost process to remove pollutants from wastewater. This method of treatment calls for an solid adsorbent which constitutes the purification tool. Agricultural wastes have been widely exploited in this case .As we know the agricultural wastes are an important source of water pollution once discharged into the aquatic environment (river, sea ...). The valorization of such wastes and their use allows the prevention of this problem with an economic and environment benefits. In this context our study aimed testing the wastewater treatment capacity by adsorption onto holocellulose resulting from the valorization of an agriculture waste. In this study, methylene blue (MB) and methyl orange (MO) are selected as models pollutants for evaluating the holocellulose adsorbent capacity. The kinetics of adsorption is performed using UV-visible spectroscopy. In order to study the effect of the main parameters for the adsorption process and their mutual interaction, a full factorial design (type nk) has been used.23 full factorial design analysis was performed to screen the parameters affecting dye removal efficiency. Using the experimental results, a linear mathematical model representing the influence of the different parameters and their interactions was obtained. The parametric study showed that efficiency of the adsorption system (Dyes/ Holocellulose) is mainly linked to pH variation. The best yields were observed for MB at pH=10 and for MO at pH=2.The kinetic data was analyzed using different models , namely , the pseudo

  3. Study of Modern Nano Enhanced Techniques for Removal of Dyes and Metals

    Directory of Open Access Journals (Sweden)

    Samavia Batool

    2014-01-01

    Full Text Available Industrial effluent often contains the significant amount of hexavalent chromium and synthetic dyes. The discharge of wastewater without proper treatment into water streams consequently enters the soil and disturbs the aquatic and terrestrial life. A range of wastewater treatment technologies have been proposed which can efficiently reduce both Cr(VI and azo dyes simultaneously to less toxic form such as biodegradation, biosorption, adsorption, bioaccumulation, and nanotechnology. Rate of simultaneous reduction of Cr(VI and azo dyes can be enhanced by combining different treatment techniques. Utilization of synergistic treatment is receiving much attention due to its enhanced efficiency to remove Cr(VI and azo dye simultaneously. This review evaluates the removal methods for simultaneous removal of Cr(VI and azo dyes by nanomicrobiology, surface engineered nanoparticles, and nanophotocatalyst. Sorption mechanism of biochar for heavy metals and organic contaminants is also discussed. Potential microbial strains capable of simultaneous removal of Cr(VI and azo dyes have been summarized in some details as well.

  4. Optical study of xanthene-type dyes in nano-confined liquid

    Science.gov (United States)

    Mahdi Shavakandi, Seyyed; Alizadeh, Khalil; Sharifi, Soheil; Marti, Othmar; Amirkhani, Masoud

    2017-04-01

    The optical activity of dye molecules in different environments is of great interest for many applications such as laser system or biological imaging. We investigate the fluorescence and absorption spectrum of nano-confined xanthene dyes (RhB and fluorescein sodium salt) in a two-phase liquid. Each show very distinct optical behavior in the water phase of a reverse microemulsion. Their optical properties such as absorption and fluorescence for different concentrations of dye and nanodroplets are investigated. We show that for the same concentration of dye in the microemulsion the peak of fluorescence intensity is varied by altering the concentration of nanodroplets. However, the trend of the change is widely different depending on the hydrophobicity of dyes. Quantum-mechanical second order perturbation theory is used to calculate the ratio of dipole moments in the ground and excited states, which accounts for the Stokes shift in fluorescence peak. Photon correlation spectroscopy is employed to check the trace of the dye in the oil phase of the microemulsion.

  5. Photocatalytic studies of crystal violet dye using mn doped and PVP capped ZnO nanoparticles.

    Science.gov (United States)

    Mittal, Manish; Sharma, Manoj; Pandey, O P

    2014-04-01

    Mn (0.5%, 1%, 1.5% and 2%) doped and undoped ZnO nanoparticles (NPs) capped with PVP (1.0%) were successfully synthesized via co-precipitation approach using zinc acetate, sodium hydroxide and manganese acetate as precursors. Structural analysis was performed by XRD confirming phase purity and crystalline wurtzite structure. TEM results show average particle size 15-20 nm and 22-25 nm for Mn (1%) and Mn (2%) doped ZnO NPs respectively. Manganese (Mn) doping has led to reduction in band gap which facilitate the absorption of radiation in visible region. The Photocatalytic activity of undoped and Mn (0.5%,1%,1.5% and 2%) doped NPs was analyzed via degradation of crystal violet (CV) dye. The crystal violet decomposition rate of undoped and Mn doped NPs were studied under UV-visible region. It is observed from degradation studies that the doping has a pronounced effect on the photocatalytic activity of ZnO NPs. Kinetic studies shows that photo degradation of CV follow a pseudo first-order kinetic law. Experiments for reusability of Mn (1%) doped with PVP (1%) capped ZnO were also performed to determine the stability of as prepared sample. It shows an increase in catalytic activity of NPs by small amount when exposed to UV irradiation for 3 h. Photoluminescence and UV-Visible absorption spectroscopy studies were also performed for studying the effect of UV irradiation on the surface of ZnO NPs.

  6. Dye tracer and morphophysical properties to observe water flow in a Gleyic Luvisol Fluxo de água em um Gleyic Luvisol usando traçador e sua relação com as propriedades físicas e morfológicas do solo

    Directory of Open Access Journals (Sweden)

    Monica Martins Silva Salvador

    2011-04-01

    Full Text Available The understanding of the preferential water flow and solute transport is important with regard to losses of nutrients and pesticides that affect the quality of the groundwater or surface water resources. Experiments using the brilliant blue dye tracer, a tension infiltrometer (TI and a double square infiltrometer (DI were carried out in the experimental field site located around 15 km southeast of the city of Rostock (North-Eastern Germany on arable land in a Pleistocene lowland landscape where corn (Zea mays L. and barley (Hordeum spp. had been cultivated. One day after dye the infiltration, a pit was dug and vertical profiles were prepared in the TI and DI sites to assess the dye pathways in the subsoil of a Gleyic Luvisol. We wanted to examine if the mottled red and white (bleached colour-pattern of the Gleyic Luvisol subsoil resulting from temporally stagnant water could be related to flow paths as visualized by dye tracing and if the soil colour could be related to other physical soil properties. Biogenic soil structures were the main transport routes conducting water and solutes into great depth in short time. These pathways had lower bulk density and less cone resistance than the adjacent red or white (bleached areas of the Gleyic Luvisol subsoil. The red areas were involved in transport because their water contents increased after as compared to before infiltration. However, the measured physical soil properties did not differ between white and red areas. We assume that red areas participate in transport at least by imbibing water from the adjacent biogenic flow paths.O fluxo preferencial de água e o transporte de solutos relacionam-se com perdas de nutrientes e pesticidas e afetam a qualidade de águas subterrâneas. Foram realizados experimentos utilizando o traçador Brilhante Blue, um infiltrômetro de tensão (TI e um infiltrômetro com "duplos quadrados" (DI num campo experimental localizado a cerca de 15 km a sudeste da cidade de

  7. Dye lasers. Citations from the NTIS data base

    Science.gov (United States)

    Cavagnaro, D. M.

    1980-08-01

    Studies on dye laser theory, design, components, optical systems, and frequency range are presented in approximately 96 citations. Abstracts on lasing dyes, pumping, tuning, excitation, molecular structure, and modulation are included. Studies on dye laser use in spectroscopy are covered.

  8. Ultrasonic enhancement of the simultaneous removal of quaternary toxic organic dyes by CuO nanoparticles loaded on activated carbon: Central composite design, kinetic and isotherm study.

    Science.gov (United States)

    Dashamiri, Somayeh; Ghaedi, Mehrorang; Dashtian, Kheibar; Rahimi, Mahmood Reza; Goudarzi, Alireza; Jannesar, Ramin

    2016-07-01

    Copper oxide nanoparticles loaded on activated carbon (CuO-NPs-AC) were prepared and fully analyzed and characterized with FE-SEM, XRD and FT-IR. Subsequently, this novel material was used for simultaneous ultrasound-assisted adsorption of brilliant green (BG), auramine O (AO), methylene blue (MB) and eosin yellow (EY) dyes. Problems regard to dyes spectra overlap in quaternary solution of this dyes were omitted by derivative spectrophotometric method. The best pH in quaternary system was studied by using one at a time method to achieved maximum dyes removal percentage. Subsequently, sonication time, adsorbent dosage and initial dyes concentrations influence on dyes removal was optimized by central composite design (CCD) combined with desirability function approach (DFA). Desirability score of 0.978 show optimum conditions set at sonication time (4.2 min), adsorbent mass (0.029 g), initial dyes concentration (4.5 mg L(-1)). Under this optimum condition the removal percentage for MB, AO, EY and BG dyes 97.58, 94.66, 96.22 and 94.93, respectively. The adsorption rate well fitted by pseudo second-order while adsorption capacity according to the Langmuir model as best equilibrium isotherm model for BG, MB, AO and EY was 20.48, 21.26, 22.34 and 21.29 mg g(-1), respectively.

  9. Testing and comparison of four ionic tracers to measure stream flow loss by multiple tracer injection

    Science.gov (United States)

    Zellweger, G.W.

    1994-01-01

    An injectate containing lithium, sodium, chloride and bromide was added continuously at five sites along a 507 m study reach of St Kevin Gulch, Lake County, Colorado to determine which sections of the stream were losing water to the stream bed and to ascertain how well the four tracers performed. The acidity of the stream (pH 3.6) made it possible for lithium and sodium, which are normally absorbed by ion exchange with stream bed sediment, to be used as conservative tracers. Net flow losses as low as 0.81 s-1, or 8% of flow, were calculated between measuring sites. By comparing the results of simultaneous injection it was determined whether subsections of the study reach were influent or effluent. Evaluation of tracer concentrations along 116 m of stream indicated that all four tracers behaved conservatively. Discharges measured by Parshall flumes were 4-18% greater than discharges measured by tracer dilution. -from Author

  10. Improving DNA data exchange: validation studies on a single 6 dye STR kit with 24 loci.

    Science.gov (United States)

    Martín, Pablo; de Simón, Lourdes Fernández; Luque, Gracia; Farfán, María José; Alonso, Antonio

    2014-11-01

    The idea of developing a new multiplex STR amplification system was conceived in 2011 as an effective way to implement the new European standard set (ESS) of 12 STR markers adopted by The Council of the European Union in 2009 while maintaining an effective compatibility and information exchange with the historical DNA profiles contained in the Spanish national DNA database (around 200,000 DNA profiles) mainly based on the 13 CODIS core STR loci plus D19S433 and D2S1338 markers. With this goal in mind we proposed to test and validate a single STR amplification system for simultaneous analysis of 21 STR markers covering both CODIS and ESS core STR loci plus three additional markers (D19S433, D2S1338, and SE33) also contained in commonly used STR kits and national DNA databases. In 2012, we started the first beta-testing with a 6-dye STR kit prototype containing 24 loci (now known as the GlobalFiler™ PCR Amplification Kit) developed by Life Technologies in response to the CODIS Core Loci Working Group's recommendation to expand the CODIS Core Loci. This prototype included our proposal of 21 autosomal STR markers and two Y-chromosome markers (DYS391 and Y-indel) and maximizes concordance with established databases and previously analyzed samples by maintaining primer sequences of previous Identifiler(®)/NGM SElect™ kits for the 21 STR markers except for TPOX. This paper describes the validation studies conducted with the first commercial available 6-dye STR kit for casework using a 3500 genetic analyzer for fragment detection that included the analysis of the following parameters and aspects: analytical threshold, sensitivity & stochastic threshold, heterozygous balance, stutter threshold, precision and accuracy, repeatability and reproducibility, genotype concordance, DNA mixtures, species specificity, and stability studies with case type samples. The studies demonstrated that the GlobalFiler™ system provided equivalent overall performance to previous forensic

  11. Statistical analysis and mathematical modeling of a tracer test on the Santa Clara River, Ventura County, California

    Science.gov (United States)

    Paybins, Katherine S.; Nishikawa, Tracy; Izbicki, John A.; Reichard, Eric G.

    1998-01-01

    To better understand flow processes, solute-transport processes, and ground-water/surface-water interactions on the Santa Clara River in Ventura County, California, a 24-hour fluorescent-dye tracer study was performed under steady-state flow conditions on a 28-mile reach of the river. The study reach includes perennial (uppermost and lowermost) subreaches and ephemeral subreaches of the lower Piru Creek and the middle Santa Clara River. Dye was injected at a site on Piru Creek, and fluorescence of river water was measured continuously at four sites and intermittently at two sites. Discharge measurements were also made at the six sites. The time of travel of the dye, peak dye concentration, and time-variance of time-concentration curves were obtained at each site. The long tails of the time-concentration curves are indicative of sources/sinks within the river, such as riffles and pools, or transient bank storage. A statistical analysis of the data indicates that, in general, the transport characteristics follow Fickian theory. These data and previously collected discharge data were used to calibrate a one-dimensional flow model (DAFLOW) and a solute-transport model (BLTM). DAFLOW solves a simplified form of the diffusion-wave equation and uses empirical relations between flow rate and cross-sectional area, and flow rate and channel width. BLTM uses the velocity data from DAFLOW and solves the advection-dispersion transport equation, including first-order decay. The simulations of dye transport indicated that (1) ground-water recharge explains the loss of dye mass in the middle, ephemeral, subreaches, and (2) ground-water recharge does not explain the loss of dye mass in the uppermost and lowermost, perennial, subreaches. This loss of mass was simulated using a linear decay term. The loss of mass in the perennial subreaches may be caused by a combination of photodecay or adsorption/desorption.

  12. Use of geochemical and isotope tracers to assess groundwater dependency of a terrestrial ecosystem: case study from southern Poland

    Science.gov (United States)

    Zurek, Anna J.; Witczak, Stanislaw; Kania, Jaroslaw; Rozanski, Kazimierz; Dulinski, Marek; Wachniew, Przemyslaw

    2015-04-01

    The presented study was aimed at better understanding of the functioning of groundwater dependent terrestrial ecosystem (GDTE) located in the south of Poland. The studied GDTE consists of a valuable forest stand (Niepolomice Forest) and associated wetland (Wielkie Bloto fen). It relies not only on shallow, unconfined aquifer but indirectly also on groundwater originating from the deeper confined aquifer, underlying the Quaternary cover and separated from it by an aquitard of variable thickness. The main objective of the study was to evaluate the contribution of groundwater to the water balance of the studied GDTE and thereby assess the potential risk to this system associated with intense exploitation of the deeper aquifer. The Wielkie Błoto fen area and the adjacent parts of Niepolomice Forest are drained by the Dluga Woda stream with 8.2 km2 of gauged catchment area. Hydrometric measurements, carried out on the Dluga Woda stream over two-year period (August 2011 - August 2013) were supplemented by chemical and isotope analyses of stream water, monitored on monthly basis. Physico-chemical parameters of the stream water (SEC, pH, Na content, Na/Cl molar ratio) and isotope tracers (deuterium, oxygen-18 and tritium) were used to quantify the expected contribution of groundwater seepage from the deeper aquifer to the water balance of the Dluga Woda catchment. The mean transit time of water through the catchment, derived from temporal variations of δ18O and tritium content in the Dluga Woda stream, was in the order of three months. This fast component of the total discharge of Dluga Woda stream is associated surface runoff and groundwater flow paths through the Quaternary cover. The slow component devoid of tritium and probably originated from the deeper Neogene aquifer is equal to approximately 30% of the total discharge. The relationships between the physico-chemical parameters of the stream water and the flow rate of Dluga Woda clearly indicate that the monitored

  13. New 1,2,4-triazole-based azo-azomethine dyes. Part II: synthesis, characterization, electrochemical properties and computational studies.

    Science.gov (United States)

    Khanmohammadi, Hamid; Erfantalab, Malihe; Bayat, Atena; Babaei, Ali; Sohrabi, Masoud

    2012-11-01

    A new series of monoiminated 1,2,4-triazole-based azo-azomethine dyes have been synthesized via condensation reaction of 4-amino-3-methyl-5-mercapto-1,2,4-triazole with various substituted azo-coupled salicylaldehyde. The dyes have been characterized by using FT-IR, UV-Vis and (1)H NMR spectroscopic methods as well as elemental analysis. The electrochemical behavior of the dyes has been investigated by cyclic voltammetry in DMSO at five different scan rates. Solvatochromic behavior of the dyes has been also investigated in four organic solvents with different polarities. Furthermore, the (1)H chemical shielding of the dyes were studied by the gauge independent atomic orbital (GIAO) method at the level of density functional theory (DFT).

  14. Experimental study of the effect of test-well arrangement for partitioning interwell tracer test on the estimation of NAPL saturation

    Science.gov (United States)

    Kim, B.; Kim, Y.; Yeo, I.; Yongcheol Kim, In Wook Yeo

    2011-12-01

    Partitioning interwell tracer test (PITT) is a method to quantify and qualify a contaminated site with NAPLs through a degree of retardation of partitioning tracers compared to a conservative one. Although PITT is known to be a more effective method to measure the saturation of spatially-distributed NAPL contaminant than the point investigation method, the saturation estimation from PITT is reported to be underestimated due to various factors including heterogeneity of the media, adsorption, source zone NAPL architecture, and long tailing in breakthrough curves of partitioning tracers. Analytical description of PITT assumes that the injection-pumping well pair is on the line of ambient groundwater flow direction, but the test-well pair could easily be off the line in the field site, which could be another erroneous factor in analyzing PITT data. The purpose of this work is to study the influence of the angle of the test-well pair to ambient groundwater flow direction based on the result from PITT. The experiments were conducted in a small-scale 3D sandbox with dimensions of 0.5 m × 0.4 m × 0.15 m (LWH) of stainless steel. The surface is covered and sealed with a plexiglass plate to make the physical model a confined aquifer. Eight full-screened wells of Teflon material were installed along the perimeter of a 50 mm circle with 45 degree intervals in the middle of the physical model. Both ends of the sand box are connected to constant head reservoirs. The physical model was wet-packed with sieved and washed sand. Trichloroethylene (TCE) and bromide were used as the contaminant and the conservative tracer, respectively. Hexanol, 2,4-dimethyl-3-pentanol and 6-methyl-2-heptanol were used as partitioning tracers. Before the injection of TCE, a PITT was conducted to measure adsorption coefficient of partitioning tracers to the sand material. TCE of 4.5 mL, dyed with Sudan IV, was injected into the inner part of the circle of the wells. PITTs using the test-well pair

  15. A prospective study on sentinel lymph node biopsy in early oral cancers using methylene blue dye alone.

    Science.gov (United States)

    Ramamurthy, Rajaraman; Kottayasamy Seenivasagam, Rajkumar; Shanmugam, Subbiah; Palanivelu, Kathirvelkumaran

    2014-09-01

    Sentinel Lymph Node (SLN) biopsy using a combination of radioisotopes and blue dyes have a good accuracy rate in predicting subclinical neck nodal metastases in head and neck cancers. However, the limited availability of lymphoscintigraphy facilities in India requires exploration of alternative methods of SLN detection. We evaluated the feasibility of using methylene blue dye alone in detecting SLN in cN0 early oral cancers. 32 patients with cN0 early (T1, T2) oral squamous cell cancers underwent SLN biopsy using peri tumoural methylene blue dye injection. Blue dye stained (SLN) nodes were sent for frozen section analyses. Patients who had microscopic metastases in SLN underwent modified radical neck dissections and the rest underwent selective neck dissections. Paraffin sections and IHC studies were done on all nodes. SLN was identified in 29 patients (Identification rate = 90.6 %) of which SLN was positive for metastases on frozen section in 5 patients. The sensitivity, specificity and NPV of SLN with frozen section were 80 %, 95.8 % and 95.8 % respectively. IHC with cytokeratins increased the sensitivity (100 %) and NPV (100 %) at the loss of specificity (87.5 %). Methylene blue dye alone can be successfully used for SLN identification in early oral cancers with a good accuracy and sensitivity. This method will be of use especially in resource limited countries and centres where nuclear medicine facilities are not widely available. However, it has to be validated by larger randomised multi institutional trials for wider applicability. Immunohistochemistry increases the sensitivity and negative predictive value of SLN but its applicability in real time decision making is limited.

  16. Optical tweezers and non-ratiometric fluorescent-dye-based studies of respiration in sperm mitochondria

    Science.gov (United States)

    Chen, Timothy; Shi, Linda Z.; Zhu, Qingyuan; Chandsawangbhuwana, Charlie; Berns, Michael W.

    2011-04-01

    The purpose of this study is to investigate how the mitochondrial membrane potential affects sperm motility using laser tweezers and a non-ratiometric fluorescent probe, DiOC6(3). A 1064 nm Nd:YVO4 continuous wave laser was used to trap motile sperm at a power of 450 mW in the trap spot. Using customized tracking software, the curvilinear velocity (VCL) and the escape force from the laser tweezers were measured. Human (Homo sapiens), dog (Canis lupis familiaris) and drill (Mandrillus leucophaeus) sperm were treated with DiOC6(3) to measure the membrane potential in the mitochondria-rich sperm midpieces. Sperm from all three species exhibited an increase in fluorescence when treated with the DiOC6(3). When a cyanide inhibitor (CCCP) of aerobic respiration was applied, sperm of all three species exhibited a reduction in fluorescence to pre-dye levels. With respect to VCL and escape force, the CCCP had no effect on dog or human sperm, suggesting a major reliance upon anaerobic respiration (glycolysis) for ATP in these two species. Based on the preliminary study on drill sperm, CCCP caused a drop in the VCL, suggesting potential reliance on both glycolysis and aerobic respiration for motility. The results demonstrate that optical trapping in combination with DiOC6(3) is an effective way to study sperm motility and energetics.

  17. Study of serum aggrecan fragments in handigodu disease precipitated by DMB dye

    Directory of Open Access Journals (Sweden)

    Mallikarjun Badadani

    2012-04-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Handigodu disease is a disorder of osteoarticular system, specific to particular region viz shimoga and chickmagalore districts of Karnataka state, India. The present study focuses to understand the metabolism of aggrecan, a key glycoprotein of cartilage matrix in Handigodu Disease (HD using serum specimen. The Dimethylmethylene Blue Chloride (DMB dye was used to precipitate glycosaminoglycans (GAGs associated proteins in serum. DMB dye was removed from GAGs associated proteins and electrophoresed on SDS-PAGE. The five GAGs associated protein bands were separated, among them two bands; 21.5 KDa and 55.4 KDa were immunoreactive to anti-human aggrecan antibody. These two GAGs associated protein bands were more dense (86% for 21.5 KDa and 61 % for 55.4 KDa in affected group when compared to unaffected group in Handigodu Disease. These results may imply defective metabolism of aggrecan in a disease condition. The study needs to be extend for other arthritis / dysplastic bone disorders. st1\\:*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  18. Tracer-based prediction of thermal reservoir lifetime: scope, limitations, and the role of thermosensitive tracers

    Science.gov (United States)

    Ghergut, I.; Behrens, H.; Karmakar, S.; Licha, T.; Nottebohm, M.; Sauter, M.

    2012-04-01

    correlation between (early) tracer signals and (later) thermal breakthrough can be re-established. Thus, thermosensitive tracers are indispensable for predicting thermal breakthrough, in such geothermal reservoirs whose 'hydrogeological personality' is given by a finite set of fractures, with flow occurring both across and along the fractures. In terms of the 'gebo benchmark-model' typology investigated by Hördt et al. (2011) [http://eposters.agu.org/abstracts/models-of-geothermal-reservoirs-as-a-basis-for-interdisciplinary-cooperation/] , such systems combine flow and transport patterns of the 'petrothermal' type and of the so-called 'deep-aquifer' type: across the fractures, heat is travelling faster than conservative-solute tracers; along the fractures, conservative-solute tracers experience much less retardation by transversal exchange (matrix diffusion), than heat; fluid (and tracer) flow is not limited to the fractures; matrix flow yields essential contribution to prolonging the fluid (and tracer) residence time. Thermal lifetime results from the opposite effects of fracture aperture as an: advection-related parameter: fluid travel time increases with increasing fracture aperture advection-unrelated parameter: fracture - matrix exchange rate increases with decreasing fracture aperture, which accelerates transport across the fracture, but retards transport along the fracture. In conservative-solute tracer signals, all these fracture aperture effects on tracer transport are masked by the very long residence time associated with the matrix flow component. Thermosensitive tracers are able to 'magnify' the visibility of fracture aperture effects against matrix flow effects. Acknowledgment: This study benefits from thermosensitive-tracer research conducted within the projects Smart Tracers and LOGRO, funded by the German Ministry for Environment, Nature Conservation and Nuclear Safety (BMU, 0327579 and 0325111B) and by Energie Baden-Württemberg (EnBW).

  19. Engineered core-shell nanofibers for electron transport study in dye-sensitized solar cells

    Science.gov (United States)

    Shabdan, Y.; Ronasi, A.; Coulibaly, P.; Moniruddin, M.; Nuraje, N.

    2017-06-01

    In this study, a unique approach was developed to synthesize 1-D core-shell nanofibers of carbon nanotubes (CNTs) and TiO2 using combination of coaxial electrospinning and sol-gel technique. Diameters of the fabricated core-shell single wall carbon nanotube-TiO2 (SWCNT-TiO2) and multi wall carbon nanotube-TiO2 (MWCNT-TiO2) nano-composite fibers were between 50-100nm. Energy dispersive spectroscopy (EDS) and X-ray photon spectroscopy (XPS) were applied to confirm encapsulation of carbon nanotube (CNT) in the core-shell structure. Electron transport properties of both SWCNT-TiO2 and MWCNT-TiO2 in the Dye-sensitized solar cells (DSSCs) were studied for the first time. It was found that SWCNT-TiO2 based DSSC provided higher short circuit current relative to MWCNT-TiO2, which was explained by I-V and bode plots. These findings were further illustrated by semi-conductive properties of SWCNT.

  20. Packed bed column studies for the removal of dyes using novel sorbent

    Directory of Open Access Journals (Sweden)

    Rajeshkannan R.

    2013-01-01

    Full Text Available A continuous fixed bed study was carried out by using tamarind seed as a sorbent for the removal of malachite green (MG and acid blue 9(AB9 from aqueous solution. The effect of factors, such as flow rate and bed depth was studied. Data confirmed that the breakthrough curves were dependent on flow rate and bed depth. Thomas, Adams-Bohart, and Yoon-Nelson models were applied to experimental data to predict the breakthrough curves using non-linear regression and to determine the characteristic parameters of the packed bed column. Bed depth/service time analysis (BDST model was used to express the effect of bed depth on breakthrough curves. The results showed that Thomas model was found suitable for the normal description of breakthrough curve at the experimental condition, while Adams-Bohart and Yoon-Nelson model were able to explain only the initial part of dynamic behaviour of the tamarind seed column. The data were in good agreement with BDST model. It was concluded that the tamarind seed can be effectively used as a sorbent for the removal of dyes.

  1. Morbidity and Mortality in 7,684 Women According to Personal Hair Dye Use: The Copenhagen City Heart Study followed for 37 Years

    Science.gov (United States)

    2016-01-01

    Background Permanent hair dye contains aromatic amines which are carcinogenic, and can cause allergic skin reactions. In the long term personal use of hair dye might therefore influence both morbidity and mortality. Objectives We tested the hypothesis that personal use of hair dye in women is associated with increased morbidity and mortality in the general population. Methods We included 7,684 women from the Copenhagen City Heart Study with information on the use of personal hair dye. We assessed the risk of cancer, skin diseases, other morbidities, and mortality during a median follow-up of 27 years (range 0–37). Results The multivariable adjusted hazard ratio for malignant melanoma in women with versus without personal use of hair dye was 2.07 (95% confidence interval 1.25–3.42). There was no increased risk of other cancer types. For other skin diseases and other major causes of morbidity we found no differences between the two groups, except for a minor excess of digestive diseases and increased risk of Parkinson’s disease among women using hair dye. Finally, we found no difference in all-cause mortality comparing women using personal hair dye or not. After correction for multiple comparisons, none of the results remained significant. However, in sensitivity analysis the excess risk of malignant melanoma remained increased with a hazard ratio of 2.58 (95%CI 1.33–5.03) among users of personal hair dye. Conclusions Personal use of hair dye does not have major influences on morbidity and mortality. Our finding of a 2-fold risk of malignant melanoma in women using hair dye is hypothesis generating. PMID:26986063

  2. Experimental and theoretical study using DFT method for the competitive adsorption of two cationic dyes from wastewaters

    Science.gov (United States)

    Regti, Abdelmajid; Ayouchia, Hicham Ben El; Laamari, My Rachid; Stiriba, Salah Eddine; Anane, Hafid; Haddad, Mohammadine El

    2016-12-01

    The adsorption of cationic dyes, Basic Yellow (BY28) and Methylene Blue (MB) on a new activated carbon from medlar species were studied in both single and binary system. Some experimental parameters, namely, pH, amount of adsorbent and contact time are studied. Quantum chemical results indicate that the adsorption efficiency was directly related to the dye electrophilicity power. Some theorical parameters were calculated and proved that MB is more electrophilic than BY28, than greatest interaction with surface sites. Kinetic study showed that the adsorption follows the pseudo-second-order model and Freundlich was the best model to describe the phenomenon in the single and binary system. According to the local reactivity results using Parr functions, the sulphur and nitrogen atoms will be the main adsorption sites.

  3. Development of a novel two color tracer perfusion technique for the hydrodynamic study of aqueous outflow in bovine eyes

    Institute of Scientific and Technical Information of China (English)

    ZHU Jing-yin; YE Wen; GONG Hai-yan

    2010-01-01

    Background Elevation of intraocular pressure is usually associated with primary open angle glaucoma and caused by increased outflow resistance. A two-color fluorescent tracer technique was developed to investigate the hydrodynamics of aqueous humor outflow with changing intraocular pressure within the same eye, to better understand the relationship between outflow facility and effective filtration area. Methods Eighteen enucleated bovine eyes were first perfused at 30 mmHg with Dulbecco's phosphate-buffered saline containing 5.5 mmol/L D-glucose. After a stable baseline facility, red fluorescent microspheres (0.5 μm, 0.002% v/v) were exchanged and perfused. Eyes in the one-color control group (n=6) were immediately perfused with fixative. In the experimental group (n=6), eyes were perfused with green tracer after intraocular pressure reduced to 7 mmHg, while in the two-color control group (n=6), eyes were perfused with green tracer with intraocular pressure remaining at 30 mmHg. All 12 eyes were then perfusion-fixed. Outflow facility was continuously recorded in all eyes. Confocal images were taken along the inner wall of the aqueous plexus and the percent of the effective filtration length (PEFL; length of inner wall exhibiting tracer labeling/total length of inner wall) was measured. The relationships between outflow facility and PEFL were analyzed statistically. Results No significant differences were found in baseline facilities (ulmin~(-1)·mmHg~(-1)) among the three groups (the experimental group: 0.93 0.12; the two-color control group: 0.90 0.19; the one-color control group: 0.98 0.13). In the experimental group, the outflow facility was significantly higher at 7 mmHg (4.29±1.01) than that at 30 mmHg (1.90±0.67, P <0.001), which corresponded to a significant increase in the PEFL at 7 mmHg (54.70±8.42) from that at 30 mmHg ((11.76±4.56)%, P<0.001). The PEFL labeled by red fluorescent microspheres in the experimental group ((11.76±4.56)%) showed no

  4. Cold Pad-Batch dyeing method for cotton fabric dyeing with reactive dyes using ultrasonic energy.

    Science.gov (United States)

    Khatri, Zeeshan; Memon, Muhammad Hanif; Khatri, Awais; Tanwari, Anwaruddin

    2011-11-01

    Reactive dyes are vastly used in dyeing and printing of cotton fibre. These dyes have a distinctive reactive nature due to active groups which form covalent bonds with -OH groups of cotton through substitution and/or addition mechanism. Among many methods used for dyeing cotton with reactive dyes, the Cold Pad Batch (CPB) method is relatively more environment friendly due to high dye fixation and non requirement of thermal energy. The dyed fabric production rate is low due to requirement of at least twelve hours batching time for dye fixation. The proposed CPB method for dyeing cotton involves ultrasonic energy resulting into a one third decrease in batching time. The dyeing of cotton fibre was carried out with CI reactive red 195 and CI reactive black 5 by conventional and ultrasonic (US) method. The study showed that the use of ultrasonic energy not only shortens the batching time but the alkalis concentrations can considerably be reduced. In this case, the colour strength (K/S) and dye fixation (%F) also enhances without any adverse effect on colour fastness of the dyed fabric. The appearance of dyed fibre surface using scanning electron microscope (SEM) showed relative straightening of fibre convolutions and significant swelling of the fibre upon ultrasonic application. The total colour difference values ΔE (CMC) for the proposed method, were found within close proximity to the conventionally dyed sample.

  5. A Study on a Solar Simulator for Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Kyoung-Jun Lee

    2012-01-01

    Full Text Available Dye-sensitized solar cells (DSSC are emerging low-cost, simple alternatives to conventional solar cells. While there has been considerable study on improving the efficiency of DSSCs, there has not been sufficient research on a photovoltaic power conditioning system adaptable to DSSCs or on a solar simulator for DSSCs. When DSSCs are commercialized in the near future, the DSSC modules must be connected to an adaptable power conditioning system in order to manage the energy produced and provide a suitable interface to the load. In the process of developing a power conditioning system, a solar simulator with the characteristics of DSSCs is essential to show the performance of the maximum power point tracking. In this paper, a virtual DSSC is designed and simulated in PSIM. Irradiation factors, temperature and shadow effects are considered in dynamic link library block in PSIM which is linked to the external C routine. A 100 W converter is built to show the performance of a DSSC as the solar simulator controlled by a digital signal processor.

  6. A comparative study of the photosensitizing characteristics of some cyanine dyes.

    Science.gov (United States)

    Delaey, E; van Laar, F; De Vos, D; Kamuhabwa, A; Jacobs, P; de Witte, P

    2000-03-01

    The present work has been carried out to explore the potential application of cyanines in photodynamic therapy. After photosensitization, the in vitro cytotoxic and antiproliferative activity on HeLa cells of a total of 35 cyanines belonging to several chemical subgroups is explored. Most of these cyanines have never been used before in similar experimental work. From a first set of experiments, it is found that none of the krypto-, oxa- and imidacyanines is photobiologically active on HeLa cells. Conversely, five thiacyanines (Thiacl-5), one rhodacyanine (Rhodac) and four indocyanines (Indoc2, Indoc4, Indoc5, Indoc7) show photodependent cytotoxicity or antiproliferative effects. A more detailed study shows that out of the ten selected compounds, eight cyanines feature significant photodependent cytotoxic and antiproliferative effects. All possess maximum absorption ranges between 545 and 824 nm. In particular, Rhodac, a tetramethinemeromonomethine rhodacyanine dye with an absorption maximum of 655 nm (ethanol) and a molar absorption coefficient epsilon = 108000 shows very promising photo-dependent biological activity. In general, the measured singlet oxygen quantum yield of the selected cyanines is low (cyanines with a partition coefficient close to 1.5 accumulate to the highest extent in HeLa cells, while the more hydrophobic compounds (e.g., indocyanines) concentrate less intracellularly.

  7. Dating of young groundwater using tritium and gaseous tracers (SF6, SF5CF3, CFC-12, H-1301): case study from southern Poland

    Science.gov (United States)

    Rozanski, Kazimierz; Bartyzel, Jakub; Dulinski, Marek; Kuc, Tadeusz; Sliwka, Ireneusz; Mochalski, Pawel; Kania, Jaroslaw; Witczak, Stanislaw

    2013-04-01

    Groundwater is an important source of potable water in many countries. While it covers ca. 50% of the global drinking water needs, in Europe this share is even higher, reaching approximately 70%. Nowadays, this strategic resource is at risk due to anthropogenic pollutants of various nature entering shallow aquifers. Proper management of groundwater resources requires thorough understanding of groundwater dynamics on time scales characteristic for the history of pollutant input to groundwater. The bomb-tritium has been used for several decades now as a tracer of choice to detect recent recharge and to quantify groundwater residence times on time scales extending from several years to several decades. The lumped-parameter modeling was the most often employed approach in this context. Since nowadays atmospheric concentrations of tritium are approaching natural levels in most parts of the world, the usage of this tracer has become more problematic. Therefore, there is a growing interest in alternative indicators of groundwater age in shallow aquifers. Anthropogenic trace gases present in the atmosphere, such as freons (CFC-11, CFC-12, CFC-113) and sulfur hexafluoride (SF6), have been applied in numerous case studies as substitutes of tritium. Here we present the results of a comprehensive study aimed at quantifying mean residence time of groundwater in the recharge area of porous sandy aquifer system located in the southern Poland. The principal economic role of the aquifer, consisting of two water-bearing strata, is to provide potable water for public and private users. The yield of the aquifer is insufficient to meet all the needs and, as a consequence, licensing conflicts arise between water supply companies and industry on the amount of water available for safe exploitation. To quantify residence time distribution (RTD) functions of water parcels arriving at the production wells located in the recharge area of the aquifer, tritium along with several gaseous tracers

  8. One-bath Dyeing of Polyester/Wool Blend with Disperse Dyes

    Institute of Scientific and Technical Information of China (English)

    蔡翔; 宋心远

    2001-01-01

    The role of auxiliary LAB as vehicle in dyeing polyester/wool blends with disperse dyes is described. Dye exhaustion and bonding on polyester/wool samples are studied under different experimental conditions - the LAB amount, the temperature and pH value- to achieve optimum conditions. The results are compared with those obtained with and without conventional dyeing auxiliary products. Although dye exhaustion is higher in the presence of commercial carriers, the dye bonded increases markedly in the presence of auxiliary LAB in both fibers. The role played by auxiliary LAB in polyester/wool blend dyeing can provide a new method for this process.

  9. Tracer monitoring of enhanced oil recovery projects

    Directory of Open Access Journals (Sweden)

    Kleven R.

    2013-05-01

    Full Text Available In enhanced oil recovery (EOR, chemicals are injected into the oil reservoir, either to increase macroscopic sweep efficiency, or to reduce remaining oil saturation in swept zones. Tracers can be used to identify reservoirs that are specifically suited for EOR operations. Injection of a selection of partitioning tracers, combined with frequent sample analysis of produced fluids, provides information suited for estimation of residual oil saturation. Tracers can also be used to evaluate and optimize the application of EOR chemicals in the reservoir. Suitable tracers will follow the EOR chemicals and assist in evaluation of retention, degradation or trapping. In addition to field applications, tracers also have a large potential as a tool to perform mechanistic studies of EOR chemicals in laboratory experiments. By labelling EOR chemicals with radioactive isotopes of elements such as H, C and S, detailed studies of transport mechanisms can be carried out. Co-injection of labelled compounds in dynamic flooding experiments in porous media will give information about retention or separation of the unique compounds constituting the chemical formulation. Separation of such compounds may be detrimental to obtaining the EOR effect expected. The paper gives new information of specific methods, and discusses current status for use of tracers in EOR operations.

  10. Determination of stream reaeration coefficients by use of tracers

    Science.gov (United States)

    Kilpatrick, F.A.; Rathbun, R.E.; Yotsukura, Nobuhiro; Parker, G.W.; DeLong, L.L.

    1989-01-01

    Stream reaeration is the physical absorption of oxygen from the atmosphere by a flowing stream. This is the primary process by which a stream replenishes the oxygen consumed in the biodegradation of organic wastes. Prior to 1965, reaeration rate coefficients could be estimated only by indirect methods. In 1965, a direct method of measuring stream reaeration coefficients was developed whereby a radioactive tracer gas was injected into a stream-the principle being that the tracer gas would be desorbed from the stream inversely to how oxygen would be absorbed. The technique has since been modified by substituting hydrocarbon gases for the radioactive tracer gas. This manual describes the slug-injection and constant-rate-injection methods of measuring gas-tracer desorption. Emphasis is on the use of rhodamine WT dye as a relatively conservative tracer and propane as the nonconservative gas tracer, on planning field tests, on methods of injection, sampling, and analysis, and on techniques for computing desorption and reaeration coefficients.

  11. Single-molecule studies of oligomer extraction and uptake of dyes in poly(dimethylsiloxane) films.

    Science.gov (United States)

    Lange, Jeffrey J; Collinson, Maryanne M; Culbertson, Christopher T; Higgins, Daniel A

    2009-12-15

    Single-molecule microscopic methods were used to probe the uptake, mobility, and entrapment of dye molecules in cured poly(dimethylsiloxane) (PDMS) films as a function of oligomer extraction. The results are relevant to the use of PDMS in microfluidic separations, pervaporation, solid-phase microextraction, and nanofiltration. PDMS films were prepared by spin-casting dilute solutions of Sylgard 184 onto glass coverslips, yielding approximately 1.4 microm thick films after curing. Residual oligomers were subsequently extracted from the films by "spin extraction". In this procedure, 200 microL aliquots of isopropyl alcohol were repeatedly dropped onto the film surface and spun off at 2000 rpm. Samples extracted 5, 10, 20, and 40 times were investigated. Dye molecules were loaded into these films by spin-casting nanomolar dye solutions onto the films. Both neutral perylene diimide (N,N'-bis(butoxypropyl)perylene-3,4,9,10-tetracarboxylic diimide) and cationic rhodamine 6G (R6G) dyes were employed. The films were imaged by confocal fluorescence microscopy. The images obtained depict nonzero populations of fixed and mobile molecules in all films. Cross-correlation methods were used to quantitatively determine the population of fixed molecules in a given region, while a Bayesian burst analysis was used to obtain the total population of molecules. The results show that the total amount of dye loaded increases with increased oligomer extraction, while the relative populations of fixed and mobile molecules decrease and increase, respectively. Bulk R6G data also show greater dye loading with increased oligomer extraction.

  12. Study of the amplified spontaneous emission in a dye-doped biopolymer-based material

    Energy Technology Data Exchange (ETDEWEB)

    Mysliwiec, J; Sznitko, L; Miniewicz, A [Institute of Physical and Theoretical Chemistry, Wroclaw University of Technology, Wyb.Wyspianskiego 27, 50-370 Wroclaw (Poland); Kajzar, F; Sahraoui, B, E-mail: jaroslaw.mysliwiec@pwr.wroc.p [Laboratoire POMA CNRS FRE 2988, Universite d' Angers, 2 Bd Lavoisier, 49 045 Angers (France)

    2009-04-21

    In this paper we investigate the amplified spontaneous emission (ASE) phenomenon in the system based on a dye dissolved in a modified deoxyribonucleic acid (DNA). The system consisted of a biopolymeric matrix made of DNA blended with cationic surfactant molecule cetyltrimethyl-ammonium chloride (CTMA) and doped with a well-known rhodamine (Rh 6G) laser dye. Thin films of the DNA-CTMA : Rh6G were excited at {lambda} = 532 nm wavelength with 8 ns laser pulses. We report on ASE intensity as a function of the laser power, dependence of polarization state of the excitation beam, ASE gain and temporal stability of the signal for the investigated system.

  13. Equilibrium, kinetics and thermodynamics studies of textile dyes adsorption on modified Tunisian clay

    Directory of Open Access Journals (Sweden)

    naghmouchi nahed

    2016-04-01

    Full Text Available The adsorption capacity of two anionic textile dyes (RR120 and BB150 on DMSO intercalated Tunisian raw clay was investigated with respect to contact time, initial dye concentration, pH and Temperature. The equilibrium data were fitted into Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherms. The kinetic parameters were calculated using pseudo-first order, pseudo second-order, intra-particle diffusion and Elovich kinetic models. The thermodynamic parameters (DH°, DS° and DG° of the adsorption process were also evaluated.

  14. Equilibrium, kinetic and thermodynamic studies of the biosorption of textile dye (Reactive Red 195) onto Pinus sylvestris L

    Energy Technology Data Exchange (ETDEWEB)

    Aksakal, Ozkan [Department of Biology, Faculty of Science, Ataturk University, Erzurum 25240 (Turkey); Ucun, Handan, E-mail: hanucun@yahoo.com [Department of Environmental Engineering, Faculty of Engineering, Bartin University, Bartin 74100 (Turkey)

    2010-09-15

    This study investigated the biosorption of Reactive Red 195 (RR 195), an azo dye, from aqueous solution by using cone biomass of Pinus sylvestris Linneo. To this end, pH, initial dye concentration, biomass dosage and contact time were studied in a batch biosorption system. Maximum pH for efficient RR 195 biosorption was found to be 1.0 and the initial RR 195 concentration increased with decreasing percentage removal. Biosorption capacity increased from 6.69 mg/g at 20 deg. C to 7.38 mg/g at 50 deg. C for 200 mg/L dye concentration. Kinetics of the interactions was tested by pseudo-first-order and pseudo-second-order kinetics, the Elovich equation and intraparticle diffusion mechanism. Pseudo-second-order kinetic model provided a better correlation for the experimental data studied in comparison to the pseudo-first-order kinetic model and intraparticle diffusion mechanism. Moreover, the Elovich equation also showed a good fit to the experimental data. Freundlich and Langmuir adsorption isotherms were used for the mathematical description of the biosorption equilibrium data. The activation energy of biosorption (Ea) was found to be 8.904 kJ/mol by using the Arrhenius equation. Using the thermodynamic equilibrium coefficients obtained at different temperatures, the study also evaluated the thermodynamic constants of biosorption ({Delta}G{sup o}, {Delta}H{sup o} and {Delta}S). The results indicate that cone biomass can be used as an effective and low-cost biosorbent to remove reactive dyes from aqueous solution.

  15. A dual tracer (68)Ga-DOTANOC PET/CT and (18)F-FDG PET/CT pilot study for detection of cardiac sarcoidosis.

    Science.gov (United States)

    Gormsen, Lars C; Haraldsen, Ate; Kramer, Stine; Dias, Andre H; Kim, Won Yong; Borghammer, Per

    2016-12-01

    Cardiac sarcoidosis (CS) is a potentially fatal condition lacking a single test with acceptable diagnostic accuracy. (18)F-FDG PET/CT has emerged as a promising imaging modality, but is challenged by physiological myocardial glucose uptake. An alternative tracer, (68)Ga-DOTANOC, binds to somatostatin receptors on inflammatory cells in sarcoid granulomas. We therefore aimed to conduct a proof-of-concept study using (68)Ga-DOTANOC to diagnose CS. In addition, we compared diagnostic accuracy and inter-observer variability of (68)Ga-DOTANOC vs. (18)F-FDG PET/CT. Nineteen patients (seven female) with suspected CS were prospectively recruited and dual tracer scanned within 7 days. PET images were reviewed by four expert readers for signs of CS and compared to the reference standard (Japanese ministry of Health and Welfare CS criteria). CS was diagnosed in 3/19 patients. By consensus, 11/19 (18)F-FDG scans and 0/19 (68)Ga-DOTANOC scans were rated as inconclusive. The sensitivity of (18)F-FDG PET for diagnosing CS was 33 %, specificity was 88 %, PPV was 33 %, NPV was 88 %, and diagnostic accuracy was 79 %. For (68)Ga-DOTANOC, accuracy was 100 %. Inter-observer agreement was poor for (18)F-FDG PET (Fleiss' combined kappa 0.27, NS) and significantly better for (68)Ga-DOTANOC (Fleiss' combined kappa 0.46, p = 0.001). Despite prolonged pre-scan fasting, a large proportion of (18)F-FDG PET/CT images were rated as inconclusive, resulting in low agreement among reviewers and correspondingly poor diagnostic accuracy. By contrast, (68)Ga-DOTANOC PET/CT had excellent diagnostic accuracy with the caveat that inter-observer variability was still significant. Nevertheless, (68)Ga-DOTANOC PET/CT looks very promising as an alternative CS PET tracer. Current Controlled Trials NCT01729169 .

  16. Dynamics of the higher lying excited states of cyanine dyes. An ultrafast fluorescence study.

    Science.gov (United States)

    Guarin, Cesar A; Villabona-Monsalve, Juan P; López-Arteaga, Rafael; Peon, Jorge

    2013-06-20

    The electronic relaxation dynamics of the second singlet excited states of several cyanine dyes was studied through the femtosecond fluorescence up-conversion technique. Our interest in these molecules comes from the potential applications of systems with upper excited singlet states with a long lifetime, which can include electron and energy transfer from the higher lying singlets after one- or two-photon absorption. We studied three series of cyanines with 4-quinolyl, 2-quinolyl, or benzothiazolyl type end groups, each with varying sp(2) carbon conjugation lengths in the methinic bridge. The dynamics after electronic excitation to singlet states above the fluorescent state vary significantly as a function of cyanine structure and conjugation length. In particular, for the 4-quinolyl series the cyanine with an intermediate conjugation length (three methinic carbons) has the slowest S2 decays with lifetimes of 5.4 ps in ethanol and 6.6 ps in ethylene glycol. On the other hand, we observed that the 2-quinolyl family has S2 decay times in the subpicosecond range independent of the conjugation length between the end groups. The slowest internal conversion was observed for the benzothiazolyl type cyanine with five methinic carbons, with an S2 lifetime of 17.3 ps in ethanol. For the planar cyanines of this study we observed for the first time a clear systematic trend in the S2 decay times which closely follow the energy gap law. It was also demonstrated that a slow S2 decay is as well observed upon excitation through degenerate two-photon absorption with near-IR pulses. The present study isolates the most important variables for the design of cyanines with long S2 lifetimes.

  17. Surfactants induced release of a red emitting dye from the nanocavity of a molecular container: A spectroscopic and calorimetric study.

    Science.gov (United States)

    Ahmed, Sayeed Ashique; Chatterjee, Aninda; Maity, Banibrata; Seth, Debabrata

    2016-08-01

    Supramolecular interaction of a red emitting dye Nile blue A (NBA) with Cucurbit[7]uril (CB7) in aqueous solution was studied and the release of the dye from the hydrophobic cavity of CB7 was reported. To investigate the supramolecular host-guest complex formation and release of dye, we have used the steady state absorption, fluorescence and time resolved fluorescence emission spectroscopy, (1)H NMR spectroscopy and isothermal titration calorimetry (ITC). The spectral properties of NBA were changed in the presence of CB7. The change in spectral features of NBA in presence of CB7 indicates the formation of supramolecular host-guest complexes. By using the SED equation the diameter of the complex was estimated. The complex formation further affirmed by the (1)H NMR study. Upfield and downfield shifts of the protons of NBA was observed in both the aliphatic and aromatic region. From the ITC measurement, we have drawn up the forces involved for the complexation of NBA with CB7. We have studied the release of NBA from the hydrophobic cavity of CB7 by using ionic, neutral surfactants and ionic liquid with the help of spectroscopic and calorimetric techniques. It is observed that on addition of SDS and ionic liquid (

  18. Air Masses Origin and Isotopic Tracers: A Study Case of the Oceanic and Mediterranean Rainfall Southwest of France

    Directory of Open Access Journals (Sweden)

    Issam Moussa

    2013-05-01

    Full Text Available Aquifers recharge mainly by local rainfall, which depend on the air mass humidity and orographic lifting, causing rain. The stable isotopes of the water molecule, i.e., oxygen-18 and deuterium, are useful tracers to determine the water source origin. Moreover, the calculation of the deuterium excess enables one to differentiate between the air masses from the Atlantic Ocean or the Mediterranean Sea. A transect from one coast to the other one and going through the city of Toulouse have been made to sample the groundwater and determine their isotopic characteristic. A monthly rainfall sampling has also been done over one year, close to the city Toulouse, to see how the d-excess values range over the season. The discussion replaces these results in available isotopic data.

  19. Applications of isotopes. [Need and cost of stable iotopes for use as tracers in biomedical and environmental studies

    Energy Technology Data Exchange (ETDEWEB)

    Kirby-Smith, J.S.

    1976-01-01

    Current and potential applications of stable isotopes as tracers in a number of biomedical and environmental areas are discussed. It is pointed out that a wide variety of problems exist in these fields whose solutions in principle are amenable to the isotopic approach. The number and diversity of these problems as well as the unique role stable isotopes can play in their solution illustrate the importance of achieving and maintaining a broad inventory of isotopic species. Experience has demonstrated unequivocally an additional overriding requirement for widespread exploration of stable isotopes by the scientific and technical community, i.e., the need for low cost availability of the materials in quantity. Some representative applications of /sup 12/C, /sup 13/C, /sup 14/N, /sup 15/N, /sup 16/O, /sup 17/O, and /sup 18/O are discussed.

  20. Comparison of /sup 13/C nuclear magnetic resonance and /sup 14/C tracer studies of hepatic metabolism. [Rats and mice

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, S.M. (Merck Inst. for Therapeutic Research, Rathway, NJ); Rognstad, R.; Shulman, R.G.; Katz, J.

    1981-04-10

    The gluconeogenic pathway from /sup 13/C-labeled substrates, each of which contained the /sup 14/C-labeled counterpart at a tracer level, has been followed in isolated rat liver cells and in isolated perfused mouse liver. The gluconeogenic flux from glycerol, the synthesis of glycogen, the synthesis of glycogen, the stimulation of glycogenolysis by glucagon, the recycling of triacylglycerol, and an increase in pentose cycle activity under the influence of phenazine methosulfate were all observed directly in the /sup 13/C NMR spectra of perfused liver or isolated hepatocytes. The relative concentrations of /sup 13/C label at specific carbons measured by the NMR spectra under these conditions agreed closely with /sup 14/C isotopic distributions measured in extracts of the same doubly labeled samples for specific activities of greater than or equal to 3%. The label distributions measured by both methods were the same to within the experimental errors, which ranged from +-2% to +-7% in these experiments.

  1. Diffusion dynamics in microfluidic dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Balslev, Søren; Mortensen, Niels Asger

    2007-01-01

    We have investigated the bleaching dynamics that occur in opto-fluidic dye lasers, where the liquid laser dye in a channel is locally bleached due to optical pumping. Our studies suggest that for micro-fluidic devices, the dye bleaching may be compensated through diffusion of dye molecules alone....... By relying on diffusion rather than convection to generate the necessary dye replenishment, our observation potentially allows for a significant simplification of opto-fluidic dye laser device layouts, omitting the need for cumbersome and costly external fluidic handling or on-chip micro-fluidic pumping...

  2. Hydrochemistry and boron isotopes as natural tracers in the study of groundwaters from North Chianan Plain, Taiwan.

    Science.gov (United States)

    Lu, Hsueh-Yu

    2014-01-01

    In this paper, hydrochemistry and boron isotopes are successfully applied to elucidate hydrogeological processes by the use of natural tracers. The hydrochemical analysis identifies four end-members in the hydrochemical evolution of groundwater from the North Chianan plain groundwater district. A few groundwater contain extraordinary chlorine concentrations of up to 48,000 mg l(-1). However, the hydrochemistry of groundwater only reveals that high saline water is a dominant factor in groundwater hydrochemistry. It is thought that these groundwater experienced precipitation of carbonates during seawater evaporation that did not involve the precipitation of gypsum. Boron isotopes are very efficient tracers in determining the source of salinisation. The boron isotopes reveal the results of mixing of evaporated seawater and water-sediment interaction. In general, the boron isotope ratio of the groundwater is controlled by a two-end-member mixing system, which is composed of evaporated seawater (isotopically heavy) and fresh surface water (isotopically light). Due to a long lagoonal period in the coastal plain, the groundwaters in the downstream area generally have high Cl/B ratios and relatively heavy boron isotope ratios while those in the upstream area are composed of low Cl/B and light boron isotopes. However, there is not a resolvable mixing trend between the Cl/B ratio and the isotopic composition of boron. It is probably obscured by a highly variable boron isotope ratio in fresh surface water and through fractionation associated with water-rock interaction. Both factors would decrease the boron isotope ratio but one effect cannot be distinguished from the other.

  3. Vertical diffusivity in the benthic boundary layer of the Oregon shelf from a deliberate tracer release experiment

    Science.gov (United States)

    Ferrón, S.; Ho, D. T.; Hales, B. R.

    2010-12-01

    A Fluorescein/SF6 deliberate tracer release experiment was conducted in benthic boundary layer (BBL) waters of the outer shelf of Oregon, as part of a multi-disciplinary research project that aims to study cross-shelf carbon transport and biogeochemical reaction rates within the BBL. The purpose of the tracers release was to examine physical transport processes, the rate of turbulent mixing and to provide a Lagrangian frame of reference for tracking other chemical species (pCO2, O2, CH4, DIC, DOC, POC, NO3-, NH4+, Fe). The tracers were injected on May 2009 during moderate upwelling favorable conditions with weak near-bottom currents, along a 4-km N-S line near the shelf streak at the 150 m isobath. Tracers distribution in the patch were tracked for over 5 days by tow-yo surveys using a winch-controlled pumping profiling vehicle that incorporated several in situ instruments such as CTD sensors, a 1200 kHz ADCP and a dye fluorometer for Fluorescein. Dissolved SF6 concentrations were analyzed on board from the underway water stream pumped from the towed vehicle by using an automated high-resolution chromatographic system equipped with an electron capture detector (ECD). The work presented here focuses on the estimation of the effective vertical diffusivity (Kz) in the BBL of the Oregon Shelf from the change in moment of the tracers’ vertical distribution, calculated using a 1D advection-diffusion model.

  4. Application of Acidic Treated Pumice as an Adsorbent for the Removal of Azo Dye from Aqueous Solutions:kinetic, Equilibrium and Thermodynamic Studies

    Directory of Open Access Journals (Sweden)

    Saied Bashiri

    2012-11-01

    Full Text Available Colored effluents are one of the important environment pollution sources since they contain unused dye compounds which are toxic and less-biodegradable. In this work removal of Acid Red 14 and Acid Red 18 azo dyes was investigated by acidic treated pumice stone as anefficient adsorbent at various experimental conditions. Removal of dye increased with increase in contact time and initial dye concentration, while decreased for increment in solution temperature and pH. Results of the equilibrium study showed that the removal ofAR14 and AR18 followed Freundlich (r2>0.99 and Langmuir (r2>0.99 isotherm models.Maximum sorption capacities were 3.1 and 29.7 mg/g for AR 14 and AR18, namely significantly higher than those reported in the literature, even for activated carbon. Fitting of experimental data onto kinetic models showed the relevance of the pseudo-second order (r2>0.99 and intra-particle diffusion (r2>0.98 models for AR14 and AR18, respectively. For both dyes, the values of external mass transfer coefficient decreased for increasing initial dye concentrations, showing increasing external mass transfer resistance at solid/liquid layer.Desorption experiments confirmed the relevance of pumice stone for dye removal, since the pH regeneration method showed 86% and 89 % regeneration for AR14 and AR18,respectively.

  5. Application of acidic treated pumice as an adsorbent for the removal of azo dye from aqueous solutions: kinetic, equilibrium and thermodynamic studies

    Directory of Open Access Journals (Sweden)

    Samarghandi Mohammad

    2012-11-01

    Full Text Available Abstract Colored effluents are one of the important environment pollution sources since they contain unused dye compounds which are toxic and less-biodegradable. In this work removal of Acid Red 14 and Acid Red 18 azo dyes was investigated by acidic treated pumice stone as an efficient adsorbent at various experimental conditions. Removal of dye increased with increase in contact time and initial dye concentration, while decreased for increment in solution temperature and pH. Results of the equilibrium study showed that the removal of AR14 and AR18 followed Freundlich (r2>0.99 and Langmuir (r2>0.99 isotherm models. Maximum sorption capacities were 3.1 and 29.7 mg/g for AR 14 and AR18, namely significantly higher than those reported in the literature, even for activated carbon. Fitting of experimental data onto kinetic models showed the relevance of the pseudo-second order (r2>0.99 and intra-particle diffusion (r2>0.98 models for AR14 and AR18, respectively. For both dyes, the values of external mass transfer coefficient decreased for increasing initial dye concentrations, showing increasing external mass transfer resistance at solid/liquid layer. Desorption experiments confirmed the relevance of pumice stone for dye removal, since the pH regeneration method showed 86% and 89% regeneration for AR14 and AR18, respectively.

  6. Synthesis of a novel polyamidoamine dendrimer conjugating with alkali blue as a lymphatic tracer and study on the lymphatic targeting in vivo.

    Science.gov (United States)

    Yang, Rui; Xia, Suxia; Ye, Tiantian; Yao, Jianhua; Zhang, Ruizhi; Wang, Shujun; Wang, Siling

    2016-09-01

    In this study, a novel lymphatic tracer polyamidoamin-alkali blue (PAMAM-AB) was synthesized in order to evaluate the intra-lymphatic targeting ability and lymphatic tropism of PAMAM-AB after subcutaneous administration. UV-Vis, FT-IR, NMR and HPLC characterization were performed to prove the successful synthesis of PAMAM-AB. The calculated AB payload of PAMAM-AB conjugate was seven per dendrimer molecule (27.16% by weight). Hydrolysis stability of PAMAM-AB in vitro was evaluated, which was stable in PBS and human plasma. Lymphatic tracing were studied to determine the blue-stained intensity of PAMAM-AB in right popliteral lymph nodes (PLNs), iliac lymph nodes (ILNs) and para-aortic lymph nodes (PALNs) after subcutaneous administration. The pharmacokinetics and biodistribution of PAMAM-AB in mice were investigated. PLNs, ILNs and PALNs could be obviously blue-stained within 10 min after PAMAM-AB administration, and displayed a more rapid lymphatic absorption, a higher AUC value in lymph nodes and a longer lymph nodes residence time compared with methylene blue solution (MB-S), MB water-in-oil microemulsion (MB-ME), MB multiple microemulsion (MB-MME). Enhanced lymphatic drainage from the injection site and uptake into lymph of PAMAM-AB indicated that PAMAM-AB possesses the double function of lymphatic tracing and lymphatic targeting, and suggested the potential for the development of lymphatic targeting vectors or as a lymphatic tracer in its own right.

  7. Quantum beats in forward scattering: subnanosecond studies with a mode-locked dye laser.

    Science.gov (United States)

    Harde, H; Burggraf, H; Mlynek, J; Lange, W

    1981-06-01

    Time-resolved polarization spectroscopy of transient coherent superpositions of atomic substates is extended to the picosecond time scale by using a synchronously pumped mode-locked dye laser. As a first demonstration, hyperfine beats in the sodium D(1) and D(2), lines were resolved. The ground-state splitting could be determined with an accuracy of better than 10(-3).

  8. Quantum beats in forward scattering - Subnanosecond studies with a mode-locked dye laser

    Science.gov (United States)

    Harde, H.; Burggraf, H.; Mlynek, J.; Lange, W.

    1981-06-01

    Time-resolved polarization spectroscopy of transient coherent superpositions of atomic substates is extended to the picosecond time scale by using a synchronously pumped mode-locked dye laser. As a first demonstration, hyperfine beats in the sodium D1 and D2 lines were resolved. The ground-state splitting could be determined with an accuracy of better than 0.001.

  9. Optimizing the Dyeing Process of Alkali-Treated Polyester Fabric with Dolu Natural Dye

    Directory of Open Access Journals (Sweden)

    M.F. Shahin

    2014-06-01

    Full Text Available An attempt has been made to optimize the process of dyeing polyester (PET fabric with natural dyes. Polyester has been first treated with NaOH solution in order to study its impact on the dyeability to the natural dye. The required and used colour component was extracted from a natural plant, namely: Rhubarb; Rheum officinale. The chemical structure of the used colouring matter is observed to have all the characteristics of a typical disperse dye. The colour strength of PET fabric was noticed to increase as a result of alkali treatment which may be attributed to the alteration in the hydrophobicity of polyester fibre. The most effective parameters that may affect the dye uptake of the natural dye on alkali-treated PET fabric and the final dyeing properties including dye bath pH, dyeing temperature and time were studied in details. The behaviour of the selected and used natural dye was found to be similar to that of disperse dyes. Addition of salicylic acid to the dye bath accelerated the rate of dyeing and subsequently higher colour strength was attained. Non- ionic dispersing agent was also used to ensure better dyeing uniformity and higher dispersion stability of dye liquor.

  10. Adsorption study of anionic reactive dye from aqueous solution to Mg-Fe-CO3 layered double hydroxide (LDH)

    Science.gov (United States)

    Ahmed, I. M.; Gasser, M. S.

    2012-10-01

    Mg-Fe-Cl Layered double hydroxides (LDHs) have been prepared using a method involving separate nucleation and aging steps with Mg/Fe = 3. The interlayer anions readily replaced by carbonate are characterized by X-ray diffraction (XRD) and FTIR. The effects of different parameters, such as pH, contact time, concentration of dye and temperature on the capacity and adsorption mechanism of Mg-Fe-CO3-LDH in removing an anionic dye (congo red, CR) from aqueous solution were separately investigated. The results show that Mg-Fe-CO3-LDH is particularly efficient in removing CR and the dye removal increases with decreasing pH. The adsorption of CR on Mg-Fe-CO3-LDH reached equilibrium after 15 min where 100 mg/L CR was removed. The equilibrium isotherm indicates that the adsorption of CR onto Mg-Fe-CO3-LDH fits to Langmuir and Freundlich equation as well. The adsorption data obtained from the Langmuir model gave good values of the determination coefficient and the saturated adsorption capacity of Mg-Fe-CO3-LDH for CR was found to be 104.6 mg/g. The regeneration study indicates that the prepared LDH could be used for several cycles. The thermodynamic parameters have been calculated, and the adsorption process was found to be spontaneous, endothermic in nature and follows a pseudo-second-order kinetic model.

  11. Bulk loading of calcium indicator dyes to study astrocyte physiology: key limitations and improvements using morphological maps.

    Science.gov (United States)

    Reeves, Alexander M B; Shigetomi, Eiji; Khakh, Baljit S

    2011-06-22

    Calcium signaling has been studied in astrocyte cell bodies using bulk loading of calcium indicator dyes, and astrocytes are known to display intracellular calcium transients. An assumption in recent data on the neuronal impact of somatic astrocyte calcium transients has been that bulk loading reflects signaling in relevant astrocyte compartments such as processes. We assessed bulk loading using Sholl analysis (Sholl, 1953) of astrocytes loaded with common calcium indicator dyes and compared these data with Sholl analysis of astrocyte morphology. In the CA1 region of the hippocampus from rats, we found that bulk loading of calcium indicator dyes only reports on calcium signals within the soma and in the most proximal processes, leaving ∼90% of the area of an astrocyte and its extensive processes unsampled. By using morphological reconstructions as "maps" after the imaging session, we present simple procedures that remedy these shortfalls and permit reliable detection of calcium transients in distal astrocyte processes. The data thus reveal limitations in the interpretation of astrocyte calcium imaging data gathered with bulk loading and provide refinements to minimize these shortcomings.

  12. Study of the degradation of dyes by MnP of Phanerochaete chrysosporium produced in a fixed-bed bioreactor.

    Science.gov (United States)

    Moldes, D; Rodríguez Couto, S; Cameselle, C; Sanromán, M A

    2003-04-01

    The production of ligninolytic enzymes by the fungus Phanerochaete chrysosporium in a fixed-bed tubular bioreactor, filled with cubes of nylon sponge, operating in semi-solid-state conditions, was studied. Maximum individual manganese-dependent peroxidase (MnP) and lignin peroxidase (LiP) activities of 1293 and 225 U/l were detected. The in vitro decolourisation of two structurally different dyes (Poly R-478, crystal violet) by the extracellular liquid obtained in the above-mentioned bioreactor was monitored in order to determine its degrading capability. The concentration of some compounds (sodium malonate, manganese sulphate) from the reaction mixture was optimised in order to maximise the decolourisation levels. A percentage of Poly R-478 decolourisation of 24% after 15 min of dye incubation was achieved. On the other hand, a methodology for a long treatment of these dyes based on the continuous addition of MnP enzyme and H(2)O(2) was developed. Moreover, this enzymatic treatment was compared with a photochemical decolourisation process. The former allowed to maintain the degradation rate almost constant for a long time, resulting in a decolourisation percentage of 70% and 30% for crystal violet and Poly R-478, respectively, after 2 h of treatment. As for the latter, it was not able to degrade Poly R-478, whereas crystal violet reached a degradation of 40% in 2 h.

  13. Efficiency improvement of new Tetrathienoacene-based dyes by enhancing donor, acceptor and bridge units, a theoretical study

    Science.gov (United States)

    Tavangar, Zahra; Zareie, Nazanin

    2016-10-01

    A series of metal free Tetrathienoacene-based (TTA-based) organic dyes are designed and investigated as sensitizers for application in dye sensitized solar cells (DSSCs). Density function theory and time dependent density function theory calculations were performed on these dyes at vacuum and orthodichlorobenzene as the solvent. Effects of changing π-conjugation bridges and different functional groups in acceptor and donor units were investigated. UV-Vis absorption spectra were simulated to show the wavelength shifting and absorption properties. Inserting nitro and acyl chloride functional groups in acceptor and NH2 in donor units leads to the reduction of HOMO-LUMO gap by lowering the lowest unoccupied molecular orbital (LUMO) energy level and raising the highest occupied molecular orbital (HOMO) energy level and the increase in effective parameters in DSSC' efficiency. The results show that changing spacer units from thiophene to furan has a great effect on electronic structure and absorption spectra. Investigation of the electron distributions of frontier orbitals shows the HOMO and LUMO localization in donor and acceptor, respectively. Some key parameters that were studied here include light harvesting efficiency, free energy of electron injection and open circuit photo-voltage.

  14. Kinetics, isothermal and thermodynamics studies of electrocoagulation removal of basic dye rhodamine B from aqueous solution using steel electrodes

    Science.gov (United States)

    Adeogun, Abideen Idowu; Balakrishnan, Ramesh Babu

    2015-09-01

    Electrocoagulation was used for the removal of basic dye rhodamine B from aqueous solution, and the process was carried out in a batch electrochemical cell with steel electrodes in monopolar connection. The effects of some important parameters such as current density, pH, temperature and initial dye concentration, on the process, were investigated. Equilibrium was attained after 10 min at 30 °C. Pseudo-first-order, pseudo-second-order, Elovich and Avrami kinetic models were used to test the experimental data in order to elucidate the kinetic adsorption process; pseudo-first-order and Avrami models best fitted the data. Experimental data were analysed using six model equations: Langmuir, Freudlinch, Redlich-Peterson, Temkin, Dubinin-Radushkevich and Sips isotherms and it was found that the data fitted well with Sips isotherm model. The study showed that the process depends on current density, temperature, pH and initial dye concentration. The calculated thermodynamics parameters (Δ G^circ ,Δ H^circ {text{and}}Δ S{^circ } ) indicated that the process is spontaneous and endothermic in nature.

  15. Photo-catalytic decolourisation of toxic dye with N-doped titania: A case study with Acid Blue 25

    Institute of Scientific and Technical Information of China (English)

    Dhruba Chakrabortty; Susmita Sen Gupta

    2013-01-01

    Dyes are one of the hazardous water pollutants.Toxic Acid Blue 25,an anthraquinonic dye,has been decolourised by photo-catalysing it with nitrogen doped titania in aqueous medium.The photo catalyst was prepared from 15% TiCl3 and 25% aqueous NH3 solution as precursor.XRD and TEM revealed the formation of well crystalline anatase phase having particle size in the nano-range.BET surface area of the sample was higher than that of pure anatase TiO2.DRS showed higher absorption of radiation in visible range compared to pure anatase TiO2.XPS revealed the presence of nitrogen in N-Ti-O environment.The experimental parameters,namely,photocatalyst dose,initial dye concentration as well as solution pH influence the decolourisation process.At pH 3.0,the N-TiO2 could decolourise almost 100% Acid Blue 25 within one hour.The influence of N-TiO2 dose,initial concentration of Acid Blue 25 and solution pH on adsorption-desorption equilibrium is also studied.The adsorption process follows Lagergren first order kinetics while the modified Langmuir-Hinselwood model is suitably fitted for photocatalytic decolourisation of Acid Blue 25.

  16. Preparation, characterization, and dye removal study of activated carbon prepared from palm kernel shell.

    Science.gov (United States)

    García, Juan Rafael; Sedran, Ulises; Zaini, Muhammad Abbas Ahmad; Zakaria, Zainul Akmar

    2017-04-08

    Palm oil mill wastes (palm kernel shell (PKS)) were used to prepare activated carbons, which were tested in the removal of colorants from water. The adsorbents were prepared by 1-h impregnation of PKS with ZnCl2 as the activating agent (PKS:ZnCl2 mass ratios of 1:1 and 2:1), followed by carbonization in autogenous atmosphere at 500 and 550 °C during 1 h. The characterization of the activated carbons included textural properties (porosity), surface chemistry (functional groups), and surface morphology. The dye removal performance of the different activated carbons was investigated by means of the uptake of methylene blue (MB) in solutions with various initial concentrations (25-400 mg/L of MB) at 30 °C, using a 0.05-g carbon/50-mL solution relationship. The sample prepared with 1:1 PKS:ZnCl2 and carbonized at 550 °C showed the highest MB adsorption capacity (maximum uptake at the equilibrium, q max = 225.3 mg MB / g adsorbent), resulting from its elevated specific surface area (BET, 1058 m(2)/g) and microporosity (micropore surface area, 721 m(2)/g). The kinetic experiments showed that removals over 90% of the equilibrium adsorptions were achieved after 4-h contact time in all the cases. The study showed that palm oil mill waste biomass could be used in the preparation of adsorbents efficient in the removal of colorants in wastewaters.

  17. Calorimetric and thermal analysis studies on the binding of phenothiazinium dye thionine with DNA polynucleotides

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Puja; Hossain, Maidul [Biophysical Chemistry Laboratory, Indian Institute of Chemical Biology, CSIR, Kolkata 700 032 (India); Suresh Kumar, Gopinatha, E-mail: gskumar@iicb.res.in [Biophysical Chemistry Laboratory, Indian Institute of Chemical Biology, CSIR, Kolkata 700 032 (India)

    2011-07-15

    Research highlights: > Thionine binds to DNA exhibiting alternating guanine-cytosine sequence selectivity. > Exothermic bindings were favoured by negative enthalpy and positive entropy changes. > The binding was characterized by strong thermal stabilization of the polynucleotides. > Complete energetics revealed from the salt and temperature dependent data. - Abstract: Binding of the phenothaizinium dye thionine with four sequence specific deoxyribopolynucleotides, poly(dG-dC).poly(dG-dC), poly(dG).poly(dC), poly(dA-dT).poly(dA-dT), and poly(dA).poly(dT) has been investigated by means of thermal helix melting, isothermal titration calorimetry, and differential scanning calorimetry experiments. The binding affinity values evaluated from isothermal titration calorimetry suggests that thionine exhibits the highest binding affinity to poly(dG-dC).poly(dG-dC). The binding to poly(dG-dC).poly(dG-dC), poly(dA-dT).poly(dA-dT), and poly(dG).poly(dC) is exothermic and favoured by negative enthalpy changes while binding to poly(dA).poly(dT) is endothermic and anomalous. The values of heat capacity changes of the interaction are negative and in the range (-0.4 to -0.5) kJ . K{sup -1} . mol{sup -1}. The binding is characterized by strong stabilization of the polynucleotides against thermal strand separation. The binding affinity values derived from thermal melting data are in excellent agreement with those obtained from isothermal titration calorimetry data. Insights into the energetic aspects and guanine-cytosine selectivity of the DNA interaction of thionine have been obtained from these studies.

  18. Fruit based Dye Sensitized Solar Cells

    Science.gov (United States)

    Ung, M. C.; Sipaut, C. S.; Dayou, J.; Liow, K. S.; Kulip, J.; Mansa, R. F.

    2017-07-01

    Dye Sensitized Solar Cell (DSSC) was first discovered in 1991 by O’regan and Gratzel. This new type of solar cell was reported to have lower production cost with efficiency as high as 12% which is comparable to conventional silicon solar cell. Initially, it uses ruthenium dye as light sensitizer for the operation. However, DSSC with ruthenium dyes are facing environment friendly issues due to the toxic chemicals and costly purification in processing ruthenium dye. Regardless of the poor performance in DSSC, natural dyes which are easy to prepare, cheap and environmental friendly still appear to be an alternative as dye sensitizer. In this study, dye sensitized solar cells (DSSCs) were fabricated using anthocyanin source dyes extracted from several local fruits. All the extracts absorb a wide range of the visible light and ultraviolet spectrum. Therefore, all of the natural dyes show light absorption properties which is important for a dye sensitizer. A DSSC is comprised of conductive substrate, nanoporous semiconductor TiO2 layer, dye sensitizer, electrolyte with redox couple and a counter electrode with catalyst. In this study, the effect of different light source and different counter electrode are been investigated. However, it is vital to know that further research need to do more on the locally Borneo sourced dyes to evaluate and enhance their performance in Dye Sensitized Solar Cell.

  19. A review of methods for modelling environmental tracers in groundwater: Advantages of tracer concentration simulation

    Science.gov (United States)

    Turnadge, Chris; Smerdon, Brian D.

    2014-11-01

    Mathematical models of varying complexity have been developed since the 1960s to interpret environmental tracer concentrations in groundwater flow systems. This review examines published studies of model-based environmental tracer interpretation, the progress of different modelling approaches, and also considers the value of modelling tracer concentrations directly rather than estimations of groundwater age. Based on citation metrics generated using the Web of Science and Google Scholar reference databases, the most highly utilised interpretation approaches are lumped parameter models (421 citations), followed closely by direct age models (220 citations). A third approach is the use of mixing cell models (99 citations). Although lumped parameter models are conceptually simple and require limited data, they are unsuitable for characterising the internal dynamics of a hydrogeological system and/or under conditions where large scale anthropogenic stresses occur within a groundwater basin. Groundwater age modelling, and in particular, the simulation of environmental tracer transport that explicitly accounts for the accumulation and decay of tracer mass, has proven to be highly beneficial in constraining numerical models. Recent improvements in computing power have made numerical simulation of tracer transport feasible. We argue that, unlike directly simulated ages, the results of tracer mass transport simulation can be compared directly to observations, without needing to correct for apparent age bias or other confounding factors.

  20. New heterocyclic green, blue and orange dyes from indazole: Synthesis, tautomerism, alkylation studies, spectroscopic characterization and DFT/TD-DFT calculations