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Sample records for bapta-based calcium dyes

  1. Calcium imaging of cortical neurons using Fura-2 AM.

    Science.gov (United States)

    Barreto-Chang, Odmara L; Dolmetsch, Ricardo E

    2009-01-19

    Calcium imaging is a common technique that is useful for measuring calcium signals in cultured cells. Calcium imaging techniques take advantage of calcium indicator dyes, which are BAPTA-based organic molecules that change their spectral properties in response to the binding of Ca2+ ions. Calcium indicator dyes fall into two categories, ratio-metric dyes like Fura-2 and Indo-1 and single-wavelength dyes like Fluo-4. Ratio-metric dyes change either their excitation or their emission spectra in response to calcium, allowing the concentration of intracellular calcium to be determined from the ratio of fluorescence emission or excitation at distinct wavelengths. The main advantage of using ratio-metric dyes over single wavelength probes is that the ratio signal is independent of the dye concentration, illumination intensity, and optical path length allowing the concentration of intracellular calcium to be determined independently of these artifacts. One of the most common calcium indicators is Fura-2, which has an emission peak at 505 nM and changes its excitation peak from 340 nm to 380 nm in response to calcium binding. Here we describe the use of Fura-2 to measure intracellular calcium elevations in neurons and other excitable cells.

  2. Estimation of presynaptic calcium currents and endogenous calcium buffers at the frog neuromuscular junction with two different calcium fluorescent dyes

    Directory of Open Access Journals (Sweden)

    Dmitry eSamigullin

    2015-01-01

    Full Text Available At the frog neuromuscular junction, under physiological conditions, the direct measurement of calcium currents and of the concentration of intracellular calcium buffers—which determine the kinetics of calcium concentration and neurotransmitter release from the nerve terminal—has hitherto been technically impossible. With the aim of quantifying both Ca2+ currents and the intracellular calcium buffers, we measured fluorescence signals from nerve terminals loaded with the low-affinity calcium dye Magnesium Green or the high-affinity dye Oregon Green BAPTA-1, simultaneously with microelectrode recordings of nerve-action potentials and end-plate currents. The action-potential-induced fluorescence signals in the nerve terminals developed much more slowly than the postsynaptic response. To clarify the reasons for this observation and to define a spatiotemporal profile of intracellular calcium and of the concentration of mobile and fixed calcium buffers, mathematical modeling was employed. The best approximations of the experimental calcium transients for both calcium dyes were obtained when the calcium current had an amplitude of 1.6 ± 0.08 рА and a half-decay time of 1.2 ± 0.06 ms, and when the concentrations of mobile and fixed calcium buffers were 250 ± 13 µM and 8 ± 0.4 mM, respectively. High concentrations of endogenous buffers define the time course of calcium transients after an action potential in the axoplasm, and may modify synaptic plasticity.

  3. Direct imaging of ER calcium with targeted-esterase induced dye loading (TED).

    Science.gov (United States)

    Samtleben, Samira; Jaepel, Juliane; Fecher, Caroline; Andreska, Thomas; Rehberg, Markus; Blum, Robert

    2013-05-07

    Visualization of calcium dynamics is important to understand the role of calcium in cell physiology. To examine calcium dynamics, synthetic fluorescent Ca(2+) indictors have become popular. Here we demonstrate TED (= targeted-esterase induced dye loading), a method to improve the release of Ca(2+) indicator dyes in the ER lumen of different cell types. To date, TED was used in cell lines, glial cells, and neurons in vitro. TED bases on efficient, recombinant targeting of a high carboxylesterase activity to the ER lumen using vector-constructs that express Carboxylesterases (CES). The latest TED vectors contain a core element of CES2 fused to a red fluorescent protein, thus enabling simultaneous two-color imaging. The dynamics of free calcium in the ER are imaged in one color, while the corresponding ER structure appears in red. At the beginning of the procedure, cells are transduced with a lentivirus. Subsequently, the infected cells are seeded on coverslips to finally enable live cell imaging. Then, living cells are incubated with the acetoxymethyl ester (AM-ester) form of low-affinity Ca(2+) indicators, for instance Fluo5N-AM, Mag-Fluo4-AM, or Mag-Fura2-AM. The esterase activity in the ER cleaves off hydrophobic side chains from the AM form of the Ca(2+) indicator and a hydrophilic fluorescent dye/Ca(2+) complex is formed and trapped in the ER lumen. After dye loading, the cells are analyzed at an inverted confocal laser scanning microscope. Cells are continuously perfused with Ringer-like solutions and the ER calcium dynamics are directly visualized by time-lapse imaging. Calcium release from the ER is identified by a decrease in fluorescence intensity in regions of interest, whereas the refilling of the ER calcium store produces an increase in fluorescence intensity. Finally, the change in fluorescent intensity over time is determined by calculation of ΔF/F0.

  4. Fast calcium and voltage-sensitive dye imaging in enteric neurones reveal calcium peaks associated with single action potential discharge.

    Science.gov (United States)

    Michel, K; Michaelis, M; Mazzuoli, G; Mueller, K; Vanden Berghe, P; Schemann, M

    2011-12-15

    Slow changes in [Ca(2+)](i) reflect increased neuronal activity. Our study demonstrates that single-trial fast [Ca(2+)](i) imaging (≥200 Hz sampling rate) revealed peaks each of which are associated with single spike discharge recorded by consecutive voltage-sensitive dye (VSD) imaging in enteric neurones and nerve fibres. Fast [Ca(2+)](i) imaging also revealed subthreshold fast excitatory postsynaptic potentials. Nicotine-evoked [Ca(2+)](i) peaks were reduced by -conotoxin and blocked by ruthenium red or tetrodotoxin. Fast [Ca(2+)](i) imaging can be used to directly record single action potentials in enteric neurones. [Ca(2+)](i) peaks required opening of voltage-gated sodium and calcium channels as well as Ca(2+) release from intracellular stores.

  5. Measurement of intracellular Ca2+ concentration in single cells using ratiometric calcium dyes.

    Science.gov (United States)

    Srikanth, Sonal; Gwack, Yousang

    2013-01-01

    Measurement of intracellular Ca(2+) concentration ([Ca(2+)](i)) is useful to study the upstream and downstream events of Ca(2+) signaling. Ca(2+)-binding proteins including EF-hand-containing proteins are important downstream effector molecules after an increase of [Ca(2+)](i). Conversely, these proteins can also act as key modulators for regulation of [Ca(2+)](i) by sensing the Ca(2+) levels in the intracellular organelles and cytoplasm. Here we describe a single-cell Ca(2+) imaging technique that was used to measure the intracellular Ca(2+) levels to examine the function of Ca(2+)-binding proteins, STIM1 and Calcium release-activated Calcium channel regulator 2A (CRACR2A), using ratiometric Ca(2+) dye Fura-2 in adherent and non-adherent cells.

  6. A highly sensitive fluorescent indicator dye for calcium imaging of neural activity in vitro and in vivo.

    Science.gov (United States)

    Tada, Mayumi; Takeuchi, Atsuya; Hashizume, Miki; Kitamura, Kazuo; Kano, Masanobu

    2014-06-01

    Calcium imaging of individual neurons is widely used for monitoring their activity in vitro and in vivo. Synthetic fluorescent calcium indicator dyes are commonly used, but the resulting calcium signals sometimes suffer from a low signal-to-noise ratio (SNR). Therefore, it is difficult to detect signals caused by single action potentials (APs) particularly from neurons in vivo. Here we showed that a recently developed calcium indicator dye, Cal-520, is sufficiently sensitive to reliably detect single APs both in vitro and in vivo. In neocortical neurons, calcium signals were linearly correlated with the number of APs, and the SNR was > 6 for in vitro slice preparations and > 1.6 for in vivo anesthetised mice. In cerebellar Purkinje cells, dendritic calcium transients evoked by climbing fiber inputs were clearly observed in anesthetised mice with a high SNR and fast decay time. These characteristics of Cal-520 are a great advantage over those of Oregon Green BAPTA-1, the most commonly used calcium indicator dye, for monitoring the activity of individual neurons both in vitro and in vivo.

  7. Monitoring of single-cell responses in the optic tectum of adult zebrafish with dextran-coupled calcium dyes delivered via local electroporation.

    Directory of Open Access Journals (Sweden)

    Vanessa Kassing

    Full Text Available The zebrafish (Danio rerio has become one of the major animal models for in vivo examination of sensory and neuronal computation. Similar to Xenopus tadpoles neural activity in the optic tectum, the major region controlling visually guided behavior, can be examined in zebrafish larvae by optical imaging. Prerequisites of these approaches are usually the transparency of larvae up to a certain age and the use of two-photon microscopy. This principle of fluorescence excitation was necessary to suppress crosstalk between signals from individual neurons, which is a critical issue when using membrane-permeant dyes. This makes the equipment to study neuronal processing costly and limits the approach to the study of larvae. Thus there is lack of knowledge about the properties of neurons in the optic tectum of adult animals. We established a procedure to circumvent these problems, enabling in vivo calcium imaging in the optic tectum of adult zebrafish. Following local application of dextran-coupled dyes single-neuron activity of adult zebrafish can be monitored with conventional widefield microscopy, because dye labeling remains restricted to tens of neurons or less. Among the neurons characterized with our technique we found neurons that were selective for a certain pattern orientation as well as neurons that responded in a direction-selective way to visual motion. These findings are consistent with previous studies and indicate that the functional integrity of neuronal circuits in the optic tectum of adult zebrafish is preserved with our staining technique. Overall, our protocol for in vivo calcium imaging provides a useful approach to monitor visual responses of individual neurons in the optic tectum of adult zebrafish even when only widefield microscopy is available. This approach will help to obtain valuable insight into the principles of visual computation in adult vertebrates and thus complement previous work on developing visual circuits.

  8. Cadmium induces transcription independently of intracellular calcium mobilization.

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    Brooke E Tvermoes

    Full Text Available BACKGROUND: Exposure to cadmium is associated with human pathologies and altered gene expression. The molecular mechanisms by which cadmium affects transcription remain unclear. It has been proposed that cadmium activates transcription by altering intracellular calcium concentration ([Ca(2+](i and disrupting calcium-mediated intracellular signaling processes. This hypothesis is based on several studies that may be technically problematic; including the use of BAPTA chelators, BAPTA-based fluorescent sensors, and cytotoxic concentrations of metal. METHODOLOGY/PRINCIPAL FINDING: In the present report, the effects of cadmium on [Ca(2+](i under non-cytotoxic and cytotoxic conditions was monitored using the protein-based calcium sensor yellow cameleon (YC3.60, which was stably expressed in HEK293 cells. In HEK293 constitutively expressing YC3.60, this calcium sensor was found to be insensitive to cadmium. Exposing HEK293::YC3.60 cells to non-cytotoxic cadmium concentrations was sufficient to induce transcription of cadmium-responsive genes but did not affect [Ca(2+](i mobilization or increase steady-state mRNA levels of calcium-responsive genes. In contrast, exposure to cytotoxic concentrations of cadmium significantly reduced intracellular calcium stores and altered calcium-responsive gene expression. CONCLUSIONS/SIGNIFICANCE: These data indicate that at low levels, cadmium induces transcription independently of intracellular calcium mobilization. The results also support a model whereby cytotoxic levels of cadmium activate calcium-responsive transcription as a general response to metal-induced intracellular damage and not via a specific mechanism. Thus, the modulation of intracellular calcium may not be a primary mechanism by which cadmium regulates transcription.

  9. Research on Resource Utilization of Dyeing Sludge with High Calcium Fly Ash%利用高钙粉煤灰对印染污泥进行资源化利用的研究

    Institute of Scientific and Technical Information of China (English)

    周何铤; 钟振宇; 黄曼; 何江伟

    2016-01-01

    This paper aims to prepare a new geopolymer material using high calcium fly ash and dyeing sludge as raw materials, and water glass and sodium hydroxide as activator. By means of standard Vicat apparatus, universal testing machine, FTIR, SEM, EDS and ICP-MS, analysis of the effect of dyeing sludge on properties of the geopolymer material was taken out. The results indicated that the setting time of the fly ash geopolymer shortened with the increase of the admixture of dyeing sludge. When its mass ratio was higher than 20%, the setting time is too short and not conducive to sample preparation. The compressive strength increased when dyeing sludge content was about 10wt%, while dropped remarkably when greater than 20wt%. Heavy metal leaching test of samples with 20wt% of dyeing sludge showed that the geopolymer had good sealing performance of heavy metals and the leaching concentration of heavy metals was far below limits.%以高钙粉煤灰为主合成材料,掺入印染污泥,并以水玻璃和氢氧化钠为激发剂,制备地质聚合物材料,并借助标准维卡仪、万能试验机、FTIR、SEM、EDS和ICP-MS等手段,分析印染污泥对该地质聚合物材料性能的影响。结果表明:粉煤灰地质聚合物的凝结时间随着印染污泥掺量增加而缩短,在掺量高于20%时,由于凝结时间太短而不利于成型;其强度在掺量为10%左右时略有提高,而当掺量大于20%时,强度极大地下降;对掺量20%的试样进行重金属浸出含量测试发现,该地质聚合物具有很好的封固重金属的性能,试样重金属浸出含量远低于限量的要求。

  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 laser

    Energy Technology Data Exchange (ETDEWEB)

    Telle, H.; Schieder, R.; Raue, R.; Eckstein, U.

    1980-05-22

    For a laser radiating in the range of wavelengths from 420 to 480 nm dye solutions are proposed. The dyes are produced by transformation of 4,4'-biphenylene-bis-(methylenoxy-2-benzaldehydes) or their bisaniles in bipolar aprotic solvents adding strongly basic alkali compounds to the benzofurans and subsequent sulfonation.

  12. Waterless Textile Dyeing

    OpenAIRE

    Odabaşoğlu, Hakkı Yasin; AVİNÇ, Osman Ozan; Arzu YAVAŞ

    2013-01-01

    Supercritical carbon dioxide (scCO), having liquid-like densities, hereby provides hydrophobic dyes an advantage on dissolving. Their gas-like low viscosities and diffusion properties can lead to shorter dyeing durations compared to conventional water dyeing process. Supercritical carbon dioxide dyeing, a novel dyeing process, is an anhydrous dyeing and this process involves the use of less energy and chemicals than conventional water dyeing processes resulting in a potential of up to 50% low...

  13. Hair dye poisoning

    Science.gov (United States)

    Hair tint poisoning ... Different types of hair dye contain different harmful ingredients. The harmful ingredients in permanent dyes are: Naphthylamine Other aromatic amino compounds Phenylenediamines Toluene ...

  14. A simple method for screening photoelectric dyes towards their use for retinal prostheses.

    Directory of Open Access Journals (Sweden)

    Matsuo T

    2003-10-01

    Full Text Available Photoelectric dyes absorb light and convert photon energy to electric potentials. To test whether these dyes could be used for retinal prostheses, a simple in vitro screening system was developed. Retinal neurons were cultured from the eyes of chick embryos at the 10-day embryonic stage, at which time no retinal photoreceptor cells have yet developed. Intracellular calcium elevation was observed with Fluo-4 in cultured retinal neurons before and after photoelectric dye was applied at varying concentrations to the culture medium. Five of 7 photoelectric dyes tested in this in vitro system induced intracellular calcium elevation in cultured chick retinal neurons. The intracellular calcium elevation generated by the 5 photoelectric dyes was blocked by extracellular calcium depletion in the case of all 5 dyes, and, except for one dye, by the presence of voltage-gated calcium channel blockers. The photoelectric dyes absorbed light under an inverted microscope and stimulated retinal neurons. This simple in vitro system allows the screening of photoelectric dyes which can be used for retinal prostheses.

  15. Calcium supplements

    Science.gov (United States)

    ... do not help. Always tell your provider and pharmacist if you are taking extra calcium. Calcium supplements ... 2012:chap 251. The National Osteoporosis Foundation (NOF). Clinician's Guide to prevention and treatment of osteoporosis . National ...

  16. Calcium rubies: a family of red-emitting functionalizable indicators suitable for two-photon Ca2+ imaging.

    Science.gov (United States)

    Collot, Mayeul; Loukou, Christina; Yakovlev, Aleksey V; Wilms, Christian D; Li, Dongdong; Evrard, Alexis; Zamaleeva, Alsu; Bourdieu, Laurent; Léger, Jean-François; Ropert, Nicole; Eilers, Jens; Oheim, Martin; Feltz, Anne; Mallet, Jean-Maurice

    2012-09-12

    We designed Calcium Rubies, a family of functionalizable BAPTA-based red-fluorescent calcium (Ca(2+)) indicators as new tools for biological Ca(2+) imaging. The specificity of this Ca(2+)-indicator family is its side arm, attached on the ethylene glycol bridge that allows coupling the indicator to various groups while leaving open the possibility of aromatic substitutions on the BAPTA core for tuning the Ca(2+)-binding affinity. Using this possibility we now synthesize and characterize three different CaRubies with affinities between 3 and 22 μM. Their long excitation and emission wavelengths (peaks at 586/604 nm) allow their use in otherwise challenging multicolor experiments, e.g., when combining Ca(2+) uncaging or optogenetic stimulation with Ca(2+) imaging in cells expressing fluorescent proteins. We illustrate this capacity by the detection of Ca(2+) transients evoked by blue light in cultured astrocytes expressing CatCh, a light-sensitive Ca(2+)-translocating channelrhodopsin linked to yellow fluorescent protein. Using time-correlated single-photon counting, we measured fluorescence lifetimes for all CaRubies and demonstrate a 10-fold increase in the average lifetime upon Ca(2+) chelation. Since only the fluorescence quantum yield but not the absorbance of the CaRubies is Ca(2+)-dependent, calibrated two-photon fluorescence excitation measurements of absolute Ca(2+) concentrations are feasible.

  17. Use of genetically-encoded calcium indicators for live cell calcium imaging and localization in virus-infected cells.

    Science.gov (United States)

    Perry, Jacob L; Ramachandran, Nina K; Utama, Budi; Hyser, Joseph M

    2015-11-15

    Calcium signaling is a ubiquitous and versatile process involved in nearly every cellular process, and exploitation of host calcium signals is a common strategy used by viruses to facilitate replication and cause disease. Small molecule fluorescent calcium dyes have been used by many to examine changes in host cell calcium signaling and calcium channel activation during virus infections, but disadvantages of these dyes, including poor loading and poor long-term retention, complicate analysis of calcium imaging in virus-infected cells due to changes in cell physiology and membrane integrity. The recent expansion of genetically-encoded calcium indicators (GECIs), including blue and red-shifted color variants and variants with calcium affinities appropriate for calcium storage organelles like the endoplasmic reticulum (ER), make the use of GECIs an attractive alternative for calcium imaging in the context of virus infections. Here we describe the development and testing of cell lines stably expressing both green cytoplasmic (GCaMP5G and GCaMP6s) and red ER-targeted (RCEPIAer) GECIs. Using three viruses (rotavirus, poliovirus and respiratory syncytial virus) previously shown to disrupt host calcium homeostasis, we show the GECI cell lines can be used to detect simultaneous cytoplasmic and ER calcium signals. Further, we demonstrate the GECI expression has sufficient stability to enable long-term confocal imaging of both cytoplasmic and ER calcium during the course of virus infections.

  18. Tunable Microfluidic Dye Laser

    DEFF Research Database (Denmark)

    Olsen, Brian Bilenberg; Helbo, Bjarne; Kutter, Jörg Peter

    2003-01-01

    We present a tunable microfluidic dye laser fabricated in SU-8. The tunability is enabled by integrating a microfluidic diffusion mixer with an existing microfluidic dye laser design by Helbo et al. By controlling the relative flows in the mixer between a dye solution and a solvent......, the concentration of dye in the laser cavity can be adjusted, allowing the wavelength to be tuned. Wavelength tuning controlled by the dye concentration was demonstrated with macroscopic dye lasers already in 1971, but this principle only becomes practically applicable by the use of microfluidic mixing...

  19. The use of size-defined DNA-functionalized calcium phosphate nanoparticles to minimise intracellular calcium disturbance during transfection.

    Science.gov (United States)

    Neumann, Sebastian; Kovtun, Anna; Dietzel, Irmgard D; Epple, Matthias; Heumann, Rolf

    2009-12-01

    Calcium phosphate-based transfection methods are frequently used to transfer DNA into living cells. However, it has so far not been studied in detail to what extend the different transfection methods lead to a net calcium uptake. Upon subsequent resolution of the calcium phosphate, intracellular free ionic calcium-surges could result, inducing as side effect various physiological responses that may finally result in cell death. Here we investigated the overall calcium uptake by the human bladder carcinoma cell line T24 during the standard calcium phosphate transfection method and also during transfection with custom-made calcium phosphate/DNA nanoparticles by isotope labelling with (45)calcium. (45)Calcium uptake was strongly increased after 7h of standard calcium phosphate transfection but not if the transfection was performed with calcium phosphate nanoparticles. Time lapse imaging microscopy using the calcium-sensitive dye Fura-2 revealed large transient increases of the intracellular free calcium level during the standard calcium phosphate transfection but not if calcium phosphate nanoparticles were used. Consistently, the viability of cells transfected by calcium phosphate/DNA nanoparticles was not changed, in remarkable contrast to the standard method where considerable cell death occurred.

  20. 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.

  1. Benzidine Dyes Action Plan

    Science.gov (United States)

    This Action Plan addresses the use of benzidine-based dyes and benzidine congener-based dyes, both metalized and non-metalized, in products that would result in consumer exposure, such as for use to color textiles.

  2. Microscopic imaging of intracellular calcium in live cells using lifetime-based ratiometric measurements of Oregon Green BAPTA-1.

    Science.gov (United States)

    Lattarulo, Carli; Thyssen, Diana; Kuchibholta, Kishore V; Hyman, Bradley T; Bacskaiq, Brian J

    2011-01-01

    Calcium is a ubiquitous intracellular messenger that has important functions in normal neuronal function. The pathology of Alzheimer's disease has been shown to alter calcium homeostasis in neurons and astrocytes. Several calcium dye indicators are available to measure intracellular calcium within cells, including Oregon Green BAPTA-1 (OGB-1). Using fluorescence lifetime imaging microscopy, we adapted this single wavelength calcium dye into a ratiometric dye to allow quantitative imaging of cellular calcium. We used this approach for in vitro calibrations, single-cell microscopy, high-throughput imaging in automated plate readers, and in single cells in the intact living brain. While OGB is a commonly used fluorescent dye for imaging calcium qualitatively, there are distinct advantages to using a ratiometric approach, which allows quantitative determinations of calcium that are independent of dye concentration. Taking advantage of the distinct lifetime contrast of the calcium-free and calcium-bound forms of OGB, we used time-domain lifetime measurements to generate calibration curves for OGB lifetime ratios as a function of calcium concentration. In summary, we demonstrate approaches using commercially available tools to measure calcium concentrations in live cells at multiple scales using lifetime contrast. These approaches are broadly applicable to other fluorescent readouts that exhibit lifetime contrast and serve as powerful alternatives to spectral or intensity readouts in multiplexing experiments.

  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. Calcium in diet

    Science.gov (United States)

    ... D is needed to help your body use calcium. Milk is fortified with vitamin D for this reason. ... of calcium dietary supplements include calcium citrate and calcium carbonate. Calcium citrate is the more expensive form of ...

  5. Ultrasonic dyeing of cellulose nanofibers.

    Science.gov (United States)

    Khatri, Muzamil; Ahmed, Farooq; Jatoi, Abdul Wahab; Mahar, Rasool Bux; Khatri, Zeeshan; Kim, Ick Soo

    2016-07-01

    Textile dyeing assisted by ultrasonic energy has attained a greater interest in recent years. We report ultrasonic dyeing of nanofibers for the very first time. We chose cellulose nanofibers and dyed with two reactive dyes, CI reactive black 5 and CI reactive red 195. The cellulose nanofibers were prepared by electrospinning of cellulose acetate (CA) followed by deacetylation. The FTIR results confirmed complete conversion of CA into cellulose nanofibers. Dyeing parameters optimized were dyeing temperature, dyeing time and dye concentrations for each class of the dye used. Results revealed that the ultrasonic dyeing produced higher color yield (K/S values) than the conventional dyeing. The color fastness test results depicted good dye fixation. SEM analysis evidenced that ultrasonic energy during dyeing do not affect surface morphology of nanofibers. The results conclude successful dyeing of cellulose nanofibers using ultrasonic energy with better color yield and color fastness results than conventional dyeing.

  6. 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...

  7. Calcium Electroporation

    DEFF Research Database (Denmark)

    Frandsen, Stine Krog; Gibot, Laure; Madi, Moinecha;

    2015-01-01

    BACKGROUND: Calcium electroporation describes the use of high voltage electric pulses to introduce supraphysiological calcium concentrations into cells. This promising method is currently in clinical trial as an anti-cancer treatment. One very important issue is the relation between tumor cell kill...... efficacy-and normal cell sensitivity. METHODS: Using a 3D spheroid cell culture model we have tested the effect of calcium electroporation and electrochemotherapy using bleomycin on three different human cancer cell lines: a colorectal adenocarcinoma (HT29), a bladder transitional cell carcinoma (SW780......), and a breast adenocarcinoma (MDA-MB231), as well as on primary normal human dermal fibroblasts (HDF-n). RESULTS: The results showed a clear reduction in spheroid size in all three cancer cell spheroids three days after treatment with respectively calcium electroporation (p

  8. Retrograde loading of nerves, tracts, and spinal roots with fluorescent dyes.

    Science.gov (United States)

    Blivis, Dvir; O'Donovan, Michael J

    2012-04-19

    Retrograde labeling of neurons is a standard anatomical method(1,2) that has also been used to load calcium and voltage-sensitive dyes into neurons(3-6). Generally, the dyes are applied as solid crystals or by local pressure injection using glass pipettes. However, this can result in dilution of the dye and reduced labeling intensity, particularly when several hours are required for dye diffusion. Here we demonstrate a simple and low-cost technique for introducing fluorescent and ion-sensitive dyes into neurons using a polyethylene suction pipette filled with the dye solution. This method offers a reliable way for maintaining a high concentration of the dye in contact with axons throughout the loading procedure.

  9. Dyes as teratogens.

    Science.gov (United States)

    Sandor, S

    1992-01-01

    The main fats and problems of the role of dyes in prenatal pathology are reviewed. The first section deals with the practical aspects related to teratological screening of industrial dyes (including also the results obtained in this laboratory). In the second section, various aspects of azo-dye teratogenesis are largely discussed, including also the experimental contributions of this laboratory. Concluding remarks are made with respect to the importance and to the perspectives of this field of research.

  10. Influence of calcium hydroxide on dyes for dentin labeling, anlyzed by means of a new methodology Influência do hidróxido de cálcio sobre corantes na marcação dentinária, analisada por meio de uma nova metodologia

    Directory of Open Access Journals (Sweden)

    Ivaldo Gomes de Moraes

    2005-09-01

    Full Text Available The objective of this study was to evaluate the influence of calcium hydroxide in intracanal dressing on the ability of the dyes rhodamine B and methylene blue to label the dentine. Forty extracted human mandibular premolars had their canals instrumented and were divided into four groups: in two groups, the canals were filled with a calcium hydroxide paste and the others remained in distilled water. After 15 days, in two groups (with and without dressing, the canals were obturated with sealer containing methylene blue, whereas the others contained rhodamine B. For analysis, the roots were transversally sectioned in their cervical, medium and apical thirds, and the labeling was analyzed. The Mann-Whitney test showed statistically significant difference between the dressing/methylene blue group and the others. Based on these results, it was concluded that calcium hydroxide in intracanal dressing negatively interferes with the labeling ability of methylene blue.Objetivou-se avaliar a influência do curativo intracanal de hidróxido de cálcio sobre a capacidade dos corantes azul de metileno e rhodamine B de marcar a dentina, quando incorporados à massa obturadora, no momento da espatulação. Quarenta pré-molares inferiores humanos extraídos tiveram seus canais instrumentados sendo, então, divididos em quatro grupos. Em dois grupos, os canais foram preenchidos com pasta de hidróxido de cálcio e propilenoglicol por 15 dias. Os outros, permaneceram em água destilada. Após a remoção do curativo, todos os canais foram obturados com condensação lateral e cimento de óxido de zinco e eugenol acrescidos de azul de metileno ou rhodamine B. Assim, em dois grupos (com e sem curativo, os canais foram obturados com cimento contendo azul de metileno e os outros, rhodamine B. Decorridos 15 dias, as raízes foram seccionadas transversalmente nos terços cervical, médio e apical, procedendo-se à análise da marcação, com atribuição de escores

  11. WATERLESS DYEING [REVIEW

    Directory of Open Access Journals (Sweden)

    DEVRENT Nalan

    2015-05-01

    Full Text Available The textile industry is believed to be one of the biggest consumers of water. Water consumption and exhaustion in dyeing textile materials in conventional methods is an important environmental problem. The cost of waste water treatment will cause a prominent problem in the future as it does today. Increasing consideration of ecologic consequences of industrial processes as well as legislation enforcing the avoidance of environmental problems have caused a reorientation of thinking and promoted projects for replacement of conventional technologies. One of these new technologies is dyeing in supercritical fluids. Dyeing with supercritical carbon dioxide is a favourable concept considering the value of water as a natural resource and the cost of waste water treatment. This dyeing method offers many advantages over conventional aqueous dyeing: During this dyeing process no water is used, therefore there is no waste water problem, no other chemicals are required; the carbon dioxide can be recycled; the dystuff which is not adsorbed on the substrate can be collected and reused; The necessary energy consumption in this process is relatively lower than is needed to heat water in conventional methods of dyeing. Due to unnecessary of drying process, it helps to save both energy and time; and dyeing cycle is shorter compared with traditional methods. In addition carbon dioxide is non-toxic and non-flammable. Supercritical fluid, supercritical dyeing, disperse dyestuffs, solid-fluid equilibrium

  12. Calcium and bones

    Science.gov (United States)

    Bone strength and calcium ... calcium (as well as phosphorus) to make healthy bones. Bones are the main storage site of calcium in ... your body does not absorb enough calcium, your bones can get weak or will not grow properly. ...

  13. Calcium Test

    Science.gov (United States)

    ... if a person has symptoms of a parathyroid disorder , malabsorption , or an overactive thyroid. A total calcium level is often measured as part of a routine health screening. It is included in the comprehensive metabolic panel (CMP) and the basic metabolic panel (BMP) , ...

  14. Calcium Carbonate

    Science.gov (United States)

    ... doctor if you have or have ever had kidney disease or stomach conditions.tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking calcium carbonate, call your doctor.

  15. Dye laser. Farbstofflaser

    Energy Technology Data Exchange (ETDEWEB)

    Telle, H.; Schieder, R.; Raue, R.; Eckstein, U.

    1987-02-12

    For a laser radiating in the range of wavelengths from 420 to 480 nm dye solutions are proposed. The dyes are produced by transformation of 4,4'-biphenylene-bis-(methylenoxy-2-benzaldehydes) or their bisaniles in bipolar aprotic solvents adding strongly basic alkali compounds to the benzofurans and subsequent sulfonation.

  16. Anaerobic azo dye reduction

    NARCIS (Netherlands)

    Zee, van der F.P.

    2002-01-01

    Azo dyes, aromatic moieties linked together by azo (-N=N-) chromophores, represent the largest class of dyes used in textile-processing and other industries. The release of these compounds into the environment is undesirable, not only because of their colour, but also because many azo

  17. Determining Compatibilities of Reactive Dyes in Pad Dyeing

    Institute of Scientific and Technical Information of China (English)

    屠天民

    2001-01-01

    Compatibilities of reactive dyes were conventionally shown by exhausting curves. But the change of proportion of dyes in padding dyebath was difficult for pad dyeing to be described by these curves. In this paper, a kind of simulation of pad dyeing process was used to determine dyestuff compatibility in pad dyeing for ramie and linen fabrics. Seven reactive dyes were divided into three groups and tested., The group with Cibacron Yellow C - 2R, Red C - R, and Blue C - R showed very good compatibility both for ramie and linen,and the other two groups of dyes gave out correspondingly low compatibilities in the pad dyeing tests. The results of the method for determining the compatibility of dyes displayed good consistency with the actul pad dyeing process.

  18. Unsymmetrical Heptamethine Dyes for NIR Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Thomas Geiger

    2014-01-01

    Full Text Available Seven unsymmetrical heptamethine dyes with carboxylic acid functionality were synthesized and characterized. These near-infrared dyes exhibit outstanding photophysical properties depending on their heterocyclic moieties and molecular structure. As proof of principle, the dyes were used as photosensitizers in dye-sensitized solar cells. Using the most promising dye, an overall conversion efficiency of 1.22% and an almost colorless solar cell were achieved.

  19. 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.

  20. Fong's: Saving Water in Dyeing

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ In an effort to save the precious water resource and reduce the environmental impact, Fong's Industries Group along with its member companies, namely "Fong's National", "THEN", "Goller" and "Fong's Water Technology" provide an ecological dyeing solution to reduce the water consumption drastically through their innovative technologies covering the processes from yarn dyeing to piece dyeing and recycling of discharge after dyeing and finishing.

  1. Diode-pumped dye laser

    Science.gov (United States)

    Burdukova, O. A.; Gorbunkov, M. V.; Petukhov, V. A.; Semenov, M. A.

    2016-10-01

    This letter reports diode pumping for dye lasers. We offer a pulsed dye laser with an astigmatism-compensated three-mirror cavity and side pumping by blue laser diodes with 200 ns pulse duration. Eight dyes were tested. Four dyes provided a slope efficiency of more than 10% and the highest slope efficiency (18%) was obtained for laser dye Coumarin 540A in benzyl alcohol.

  2. Further Development of Selective Dyeing Method for Detecting Chrysotile Asbestos in Building Materials

    Science.gov (United States)

    Oke, Y.; Yamasaki, N.; Maeta, N.; Fujimaki, H.; Hashida, T.

    2008-02-01

    Extensive usage of chrysotile asbestos has resulted in the remains of large numbers of chrysotile asbestos-containing buildings to be surveyed. We have recently developed a simple dyeing method for detecting chrysotile asbestos in building materials, which involves pretreatment with calcium-chelating agent and dyeing treatment with magnesium-chelating organic dyes. In this study, we further developed a method which eliminates dyed asbestos substitutes containing magnesium, potentially present in building materials. In the new method, post-treatment with formic acid was conducted to dissolve the non-chrysotile asbestos materials in order to delineate dyed chrysotile asbestos. The calcium-masking process was also shown to be an essential process even when the post-treatment was conducted. It was shown that the new method developed in this study may enable us to dye chrysotile asbestos only without detecting asbestos substitutes in building materials.

  3. Dye Application, Manufacture of Dye Intermediates and Dyes

    Science.gov (United States)

    Freeman, H. S.; Mock, G. N.

    It is difficult if not impossible to determine when mankind first systematically applied color to a textile substrate. The first colored fabrics were probably nonwoven felts painted in imitation of animal skins. The first dyeings were probably actually little more than stains from the juice of berries. Ancient Greek writers described painted fabrics worn by the tribes of Asia Minor. But just where did the ancient craft have its origins? Was there one original birthplace or were there a number of simultaneous beginnings around the world?

  4. EFFECTS OF PDGF-BB ON INTRACELLULAR CALCIUM CONCENTRATION AND PROLIFERATION IN CULTURED GLOMERULAR MESANGIAL CELLS

    Institute of Scientific and Technical Information of China (English)

    WEN Li-ping; ZHANG Chong; BIAN Fan; ZOU Jun; JIANG Geng-ru; ZHU Han-wei

    2006-01-01

    Objective To investigate the relationship between the alteration of intracellular calcium concentration and proliferation in cultured glomerular mesangial cells. Methods Rat mesangial cells were cultured.Intracellular calcium concentrations were measured by confocal Laser Scanning Microscopy and Fura-3 fluorescence dyeing techniques. Cell growth was measured by MTT assay. Results PDGF-BB increased intracellular calcium concentrations in a dose-dependent manner, and at the same time promote the proliferation of mesangial cells. After preincubation with calcium channel blocker nifedipine or angiotensin converting enzyme inhibitor captopril, both the increase of intracellular calcium concentrations and cell proliferations induced by PDGF-BB were inhibited. Tripterigium Wilfordii Glycosides (TMG) significantly inhibited the mesangial cell proliferations, but it had no significant effect on intracellular calcium concentrations. Conclusion There was a positive relationship between the elevation of intracellular calcium concentration and cell proliferation in glomerular mesangial cells, but the increase of in- tracellular calcium concentrations wasn't the only way for proliferation.

  5. Calmodulin activation by calcium transients in the postsynaptic density of dendritic spines.

    Directory of Open Access Journals (Sweden)

    Daniel X Keller

    Full Text Available The entry of calcium into dendritic spines can trigger a sequence of biochemical reactions that begins with the activation of calmodulin (CaM and ends with long-term changes to synaptic strengths. The degree of activation of CaM can depend on highly local elevations in the concentration of calcium and the duration of transient increases in calcium concentration. Accurate measurement of these local changes in calcium is difficult because the spaces are so small and the numbers of molecules are so low. We have therefore developed a Monte Carlo model of intracellular calcium dynamics within the spine that included calcium binding proteins, calcium transporters and ion channels activated by voltage and glutamate binding. The model reproduced optical recordings using calcium indicator dyes and showed that without the dye the free intracellular calcium concentration transient was much higher than predicted from the fluorescent signal. Excitatory postsynaptic potentials induced large, long-lasting calcium gradients across the postsynaptic density, which activated CaM. When glutamate was released at the synapse 10 ms before an action potential occurred, simulating activity patterns that strengthen hippocampal synapses, the calcium gradient and activation of CaM in the postsynaptic density were much greater than when the order was reversed, a condition that decreases synaptic strengths, suggesting a possible mechanism underlying the induction of long-term changes in synaptic strength. The spatial and temporal mechanisms for selectivity in CaM activation demonstrated here could be used in other signaling pathways.

  6. Laser dye technology

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, P R

    1999-09-01

    The author has worked with laser dyes for a number of years. A first interest was in the Navy blue-green program where a flashlamp pumped dye laser was used as an underwater communication and detection device. It made use of the optical window of sea-water--blue for deep ocean, green for coastal water. A major activity however has been with the Atomic Vapor Laser Isotope Separation Program (AVLIS) at the Lawrence Livermore National Laboratory. The aim here has been enriching isotopes for the nuclear fuel cycle. The tunability of the dye laser is utilized to selectively excite one isotope in uranium vapor, and this isotope is collected electrostatically as shown in Figure 1. The interests in the AVLIS program have been in the near ultra-violet, violet, red and deep-red.

  7. Croatian Traditional Herbal Dyes For Textile Dyeing

    OpenAIRE

    Sutrlović, Ana

    2011-01-01

    Textiles, namely protein fibers, in continental part of central Europe have been traditionally dyed by natural dyes. In the process textile materials were pre or after treated by metal salts – mordants (usually: KAl(SO4)2•12H2O, SnCl2•2H2O, FeSO4•7H2O, CuSO4•5H2O). Most represented active substances in herbal extracts are flavonoid derivatives, which by complexing with metal ions constitute colored complexes. Depending on herb species and mordant applied, a wide palette of colors is available...

  8. Dyes with high affinity for polylactide

    Institute of Scientific and Technical Information of China (English)

    Liang He; Shu Fen Zhang; Bing Tao Tang; Li Li Wang; Jin Zong Yang

    2007-01-01

    Attempts were made to develop dyes with high affinity for polylactide as an alternative to the existent commercial disperse dyes.The dyes synthesized according to the affinity concept of dye to polylactide exhibited excellent dyeing properties on polylactide compared with the commercial disperse dyes.

  9. Textile dye decolorization using cyanobacteria.

    Science.gov (United States)

    Parikh, Amit; Madamwar, Datta

    2005-03-01

    Cyanobacterial cultures isolated from sites polluted by industrial textile effluents were screened for their ability to decolorize cyclic azo dyes. Gloeocapsa pleurocapsoides and Phormidium ceylanicum decolorized Acid Red 97 and FF Sky Blue dyes by more than 80% after 26 days. Chroococcus minutus was the only culture which decolorized Amido Black 10B (55%). Chlorophyll a synthesis in all cultures was strongly inhibited by the dyes. Visible spectroscopy and TLC confirmed that color removal was due to degradation of the dyes.

  10. Hair care and dyeing.

    Science.gov (United States)

    Draelos, Zoe Diana

    2015-01-01

    Alopecia can be effectively camouflaged or worsened through the use of hair care techniques and dyeing. Proper hair care, involving hair styling and the use of mild shampoos and body-building conditioners, can amplify thinning scalp hair; however, chemical processing, including hair dyeing, permanent waving, and hair straightening, can encourage further hair loss through breakage. Many patients suffering from alopecia attempt to improve their hair through extensive manipulation, which only increases problems. Frequent haircuts to minimize split ends, accompanied by gentle handling of the fragile fibers, is best. This chapter offers the dermatologist insight into hair care recommendations for the alopecia patient.

  11. Azaquinolone dye lasers

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, P.R.; Atkins, R.L.; Henry, R.A.; Fletcher, A.N.

    1978-07-25

    The invention provides a dye laser comprising a lasing solution of a 7-substituted azaquinolone-2 in which the aza nitrogen occupies at least one of the 5, 6 and 8 ring positions. The 7-substituent is hydroxy, alkoxy, amino or substituted amino. Substituents may be attached to other ring positions. The present lasing compounds are aza analogs of corresponding quinolone compounds and, hence, are named ''azaquinolone'' compounds. The dye lasers lase in the blue to near ultraviolet region.

  12. Calcium and Vitamin D

    Science.gov (United States)

    ... Cart Home › Patients › Treatment › Calcium/Vitamin D Calcium/Vitamin D Getting enough calcium and vitamin D is ... the-counter medications and calcium supplements. What is Vitamin D and What Does it Do? Vitamin D ...

  13. Imaging calcium in neurons.

    Science.gov (United States)

    Grienberger, Christine; Konnerth, Arthur

    2012-03-08

    Calcium ions generate versatile intracellular signals that control key functions in all types of neurons. Imaging calcium in neurons is particularly important because calcium signals exert their highly specific functions in well-defined cellular subcompartments. In this Primer, we briefly review the general mechanisms of neuronal calcium signaling. We then introduce the calcium imaging devices, including confocal and two-photon microscopy as well as miniaturized devices that are used in freely moving animals. We provide an overview of the classical chemical fluorescent calcium indicators and of the protein-based genetically encoded calcium indicators. Using application examples, we introduce new developments in the field, such as calcium imaging in awake, behaving animals and the use of calcium imaging for mapping single spine sensory inputs in cortical neurons in vivo. We conclude by providing an outlook on the prospects of calcium imaging for the analysis of neuronal signaling and plasticity in various animal models.

  14. Portable fluorescence photometer for monitoring free calcium

    Science.gov (United States)

    Struckmeier, Jens; Klopp, Erk; Born, Matthias; Hofmann, Martin; Tenbosch, Jochen; Jones, David B.

    2000-12-01

    We introduce a compact and portable photometric system for measurements of the calcium dynamics in cells. The photometer is designed for applications in centrifuges or in zero gravity environment and thus extremely compact and reliable. It operates with the calcium-sensitive dye Indo-1. The excitation wavelength of 345 nm is generated by frequency doubling of a laser diode. Two compact photomultiplier tubes detect the fluorescent emission. The electronics provide the sensitivity of photon counting combined with simultaneous measurement of the temperature, of air pressure, and of gravitational force. Internal data storage during the experiment is possible. A newly developed cell chamber stabilizes the cell temperature to 37.0±0.1 °C and includes a perfusion system to supply the cells with medium. The system has a modular setup providing the possibility of changing the light source and detectors for investigation of ions other than calcium. Measurements of the intracellular calcium concentration are based on a comprehensive calibration of our system. First experiments show that the calcium dynamics of osteosarcoma cells stimulated by parathyroid hormone is observable.

  15. Levitated droplet dye laser

    DEFF Research Database (Denmark)

    Azzouz, H.; Alkafadiji, L.; Balslev, Søren

    2006-01-01

    a high quality optical resonator. Our 750 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. The droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating...

  16. Microfluidic Dye Lasers

    DEFF Research Database (Denmark)

    Kristensen, Anders; Balslev, Søren; Gersborg-Hansen, Morten

    2006-01-01

    A technology for miniaturized, polymer based lasers, suitable for integration with planar waveguides and microfluidic networks is presented. The microfluidic dye laser device consists of a microfluidic channel with an embedded optical resonator. The devices are fabricated in a thin polymer film...

  17. Alzheimer's Dye Test?

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Massachusetts Institute of Technology (MIT) scientists have developed a new dye that could offer noninvasive early diagnosis of Alzheimer's disease, a discovery that could aid in monitoring the progression of the disease and in studying the efficacy of new treatments to stop it. The work is published in Angewandte Chemie. Today, doctors can only…

  18. Synthesis of azo pyridone dyes

    OpenAIRE

    Mijin Dušan Ž.; Ušćumlić Gordana S.; Valentić Nataša V.; Marinković Aleksandar D.

    2011-01-01

    Over 50% of all colorants which are used nowdays are azo dyes and pigments, and among them arylazo pyridone dyes (and pigments) have became of interest in last several decades due to the high molar extinction coefficient, and the medium to high light and wet fastness properties. They find application generally as disperse dyes. The importance of disperse dyes increased in the 1970s and 1980s due to the use of polyester and nylon as the main synthetic fibers. Also, disperse dyes were use...

  19. TEXTILE DYEING AND FINISHING JOURNAL

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Abstract: Optim is dyed with Lanasol CE series dyes by micro-suspension technology, and the dyeing result is compared with that by traditional process. The optimal micro-suspension dyeing process is determined as follows: formic acid 1.5% (owl), micro-suspension promoter WR1.0% (owf), micro-suspension promoter TS 0.5 % (owl), dyestuff 5% (owf). The results show that micro-suspension dyeing increases the dye uptake percentage and colour fixation rate significantly; improves the handle and bulkiness without damaging the colour fastness of the dyed fabric.

  20. Dye laser principles with applications

    CERN Document Server

    Duarte, Frank J; Liao, Peter F; Kelley, Paul

    1990-01-01

    A tutorial introduction to the field of dye lasers, Dye Laser Principles also serves as an up-to-date overview for those using dye lasers as research and industrial tools. A number of the issues discussed in this book are pertinent not only to dye lasers but also to lasers in general. Most of the chapters in the book contain problem sets that expand on the material covered in the chapter.Key Features* Dye lasers are among the most versatile and successful laser sources currently available in use Offering both pulsed and continuous-wave operation and tunable from the near ultraviole

  1. 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.

  2. Optical Properties of Fluorescent Dyes

    Institute of Scientific and Technical Information of China (English)

    李戎; 陈东辉

    2001-01-01

    Fluorescent dyes have been widely used these years.Because of the special optical performance, conventional CCM systems seem to be unable to predict the recipes of fabrics dyed with fluorescent dyes. In order to enhance the functions of CCM systems, the optical properties of fluorescent dyes in their absorption region were investigated. It has been found that there was a fixed maximum absorption wavelength for each fluorescent dyes whatever its concentration is. Both absorption region and maximum absorption wavelength of the dyes in solution are the same to those in fabric, and that the absorption is directly proportional to the concentration of the dye. So the optical properties obtained in solutions cna be applied for describing the optics performance of fluorescent dyes in fabrics.

  3. Asante Calcium Green and Asante Calcium Red--novel calcium indicators for two-photon fluorescence lifetime imaging.

    Science.gov (United States)

    Jahn, Karolina; Hille, Carsten

    2014-01-01

    For a comprehensive understanding of cellular processes and potential dysfunctions therein, an analysis of the ubiquitous intracellular second messenger calcium is of particular interest. This study examined the suitability of the novel Ca2+-sensitive fluorescent dyes Asante Calcium Red (ACR) and Asante Calcium Green (ACG) for two-photon (2P)-excited time-resolved fluorescence measurements. Both dyes displayed sufficient 2P fluorescence excitation in a range of 720-900 nm. In vitro, ACR and ACG exhibited a biexponential fluorescence decay behavior and the two decay time components in the ns-range could be attributed to the Ca(2+)-free and Ca(2+)-bound dye species. The amplitude-weighted average fluorescence decay time changed in a Ca(2+)-dependent way, unraveling in vitro dissociation constants K(D) of 114 nM and 15 nM for ACR and ACG, respectively. In the presence of bovine serum albumin, the absorption and steady-state fluorescence behavior of ACR was altered and its biexponential fluorescence decay showed about 5-times longer decay time components indicating dye-protein interactions. Since no ester derivative of ACG was commercially available, only ACR was evaluated for 2P-excited fluorescence lifetime imaging microscopy (2P-FLIM) in living cells of American cockroach salivary glands. In living cells, ACR also exhibited a biexponential fluorescence decay with clearly resolvable short (0.56 ns) and long (2.44 ns) decay time components attributable to the Ca(2+)-free and Ca(2+)-bound ACR species. From the amplitude-weighted average fluorescence decay times, an in situ K(D) of 180 nM was determined. Thus, quantitative [Ca(2+)]i recordings were realized, unraveling a reversible dopamine-induced [Ca(2+)]i elevation from 21 nM to 590 nM in salivary duct cells. It was concluded that ACR is a promising new Ca(2+) indicator dye for 2P-FLIM recordings applicable in diverse biological systems.

  4. Asante Calcium Green and Asante Calcium Red--novel calcium indicators for two-photon fluorescence lifetime imaging.

    Directory of Open Access Journals (Sweden)

    Karolina Jahn

    Full Text Available For a comprehensive understanding of cellular processes and potential dysfunctions therein, an analysis of the ubiquitous intracellular second messenger calcium is of particular interest. This study examined the suitability of the novel Ca2+-sensitive fluorescent dyes Asante Calcium Red (ACR and Asante Calcium Green (ACG for two-photon (2P-excited time-resolved fluorescence measurements. Both dyes displayed sufficient 2P fluorescence excitation in a range of 720-900 nm. In vitro, ACR and ACG exhibited a biexponential fluorescence decay behavior and the two decay time components in the ns-range could be attributed to the Ca(2+-free and Ca(2+-bound dye species. The amplitude-weighted average fluorescence decay time changed in a Ca(2+-dependent way, unraveling in vitro dissociation constants K(D of 114 nM and 15 nM for ACR and ACG, respectively. In the presence of bovine serum albumin, the absorption and steady-state fluorescence behavior of ACR was altered and its biexponential fluorescence decay showed about 5-times longer decay time components indicating dye-protein interactions. Since no ester derivative of ACG was commercially available, only ACR was evaluated for 2P-excited fluorescence lifetime imaging microscopy (2P-FLIM in living cells of American cockroach salivary glands. In living cells, ACR also exhibited a biexponential fluorescence decay with clearly resolvable short (0.56 ns and long (2.44 ns decay time components attributable to the Ca(2+-free and Ca(2+-bound ACR species. From the amplitude-weighted average fluorescence decay times, an in situ K(D of 180 nM was determined. Thus, quantitative [Ca(2+]i recordings were realized, unraveling a reversible dopamine-induced [Ca(2+]i elevation from 21 nM to 590 nM in salivary duct cells. It was concluded that ACR is a promising new Ca(2+ indicator dye for 2P-FLIM recordings applicable in diverse biological systems.

  5. FY 1980 Report on Dye Laser Materials

    Science.gov (United States)

    1981-02-01

    by block number) Dye Lasers Laser Dyes Tunable Lasers Photodegradation Rhodamine Dyes 20. ABSTRACT (Continue n resld* it necesiry and Identify by block...limited usefulness as a portable military device because of the photodegradation of the dye solution. Although there have been state-of-the-art reviews...on laser dyes , 1𔃼 the photodegradation of laser dyes ,3 and dye lasers, 4- 6 only authors from, or funded by, military organizations have given strict

  6. Plantas Tintureiras Dye Plants

    Directory of Open Access Journals (Sweden)

    Maria do Carmo Serrano

    2008-12-01

    Full Text Available Existe uma vasta bibliografia, até ao séc. XVIII, sobre plantas produtoras de corantes naturais, sendo que apenas um número limitado foi utilizado no tingimento de têxteis antigos, devido à capacidade de resistência à lavagem e ao desvanecimento. O cultivo de plantas ou a sua existência no mundo silvestre tiveram uma enorme importância sócio-económica para muitas comunidades espalhadas pelo mundo e pelas intensas trocas comerciais que geraram. A extracção dos corantes era feita a partir de diferentes partes de plantas ou árvores. Nalgumas plantas eram utilizadas as folhas, enquanto noutras se aproveitavam as flores, as raízes, os frutos, troncos ou sementes. Os corantes podiam ser extraídos através de processos complexos que envolviam diversas operações como maceração, destilação, fermentação, decantação, precipitação, filtração, etc. Neste âmbito, são apresentadas algumas das plantas cultivadas em Portugal e em muitos outros países europeus e que foram usadas em tinturaria. Este trabalho pretende ser um contributo para obstar à perda de conhecimentos das condições de cultivo e da forma como se maximizava a produção de corantes.A vast bibliography exists, until the 18th cen-tury, on natural dyes obtained from plants, but only one limited number was used in the dyeing of old textiles, due to capacity of resistance to wash and light fading. The culture of plants or its existence in the wild world had an enormous economical importance for many communities spread for the world, and the intense commercial exchanges that had generated. The extraction of dyes was done from different parts of plants or trees. In some plants was used the leaves, others, only the roots, the fruits, trunks or seeds. The dyes could be extracted through complex processes that involved various operations as maceration, distillation, fermentation, decantation, precipitation, filtration, etc. In this scope, some of the plants cultivated in

  7. Intercellular calcium signaling and nitric oxide feedback during constriction of rabbit renal afferent arterioles

    DEFF Research Database (Denmark)

    Uhrenholt, Torben Rene; Schjerning, J; Vanhoutte, Paul M. G.;

    2007-01-01

    in microperfused rabbit renal afferent arterioles, using fluorescence imaging microscopy with the calcium-sensitive dye fura-2 and the NO-sensitive dye 4-amino-5-methylamino-2',7'-difluorescein. Both dyes were loaded into smooth muscle and endothelium. Depolarization with 100 mmol/l KCl led to a transient......Vasoconstriction and increase in the intracellular calcium concentration ([Ca(2+)](i)) of vascular smooth muscle cells may cause an increase of endothelial cell [Ca(2+)](i), which, in turn, augments nitric oxide (NO) production and inhibits smooth muscle cell contraction. This hypothesis was tested...... vasoconstriction which was converted into a sustained response by N-nitro-l-arginine methyl ester (l-NAME). Depolarization increased smooth muscle cell [Ca(2+)](i) from 162 +/- 15 nmol/l to a peak of 555 +/- 70 nmol/l (n = 7), and this response was inhibited by 80% by the l-type calcium channel blocker...

  8. Synthesis of azo pyridone dyes

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2011-01-01

    Full Text Available Over 50% of all colorants which are used nowdays are azo dyes and pigments, and among them arylazo pyridone dyes (and pigments have became of interest in last several decades due to the high molar extinction coefficient, and the medium to high light and wet fastness properties. They find application generally as disperse dyes. The importance of disperse dyes increased in the 1970s and 1980s due to the use of polyester and nylon as the main synthetic fibers. Also, disperse dyes were used rapidly since 1970 in inks for the heat-transfer printing of polyester. The main synthetic route for the preparation of azo dyes is coupling reaction between an aromatic diazo compound and a coupling component. Of all dyes manufactured, about 60% are produced by this reaction. Arylazo pyridone dyes can be prepared from pyridone moiety as a coupling component, where substituent can be on nitrogen, and diazonim salts which can be derived from different substituted anilines or other heterocyclic derivatives. In addition, arylazo dyes containing pyridone ring can be prepared from arylazo diketones or arylazo ketoesters (obtained by coupling β-diketones or β-ketoesters with diazonim salts by condensation with cyanoacetamide. Disazo dyes can be prepared by tetrazotizing a dianiline and coupling it with a pyridone or by diazotizing aniline and coupling it with a dipyridone. Trisazo dyes can be also prepared by diazotizing of aniline and coupling it with a tripyridone or by hexazotizing a trianiline and coupling it with a pyridone. The main goal of this paper is to give a brief review on the synthesis of arylazo pyridone dyes due to the lack of such reviews. In addition, some properties of arylazo pyridone dyes as light fastness and azo-hydrazon tautomerism are disccused.

  9. Dyeing fabrics with metals

    Science.gov (United States)

    Kalivas, Georgia

    2002-06-01

    Traditionally, in textile dyeing, metals have been used as mordants or to improve the color produced by a natural or synthetic dye. In biomedical research and clinical diagnostics gold colloids are used as sensitive signals to detect the presence of pathogens. It has been observed that when metals are finely divided, a distinct color may result that is different from the color of the metal in bulk. For example, when gold is finely divided it may appear black, ruby or purple. This can be seen in biomedical research when gold colloids are reduced to micro-particles. Bright color signals are produced by few nanometer-sized particles. Dr. William Todd, a researcher in the Department of Veterinary Science at the Louisiana State University, developed a method of dyeing fabrics with metals. By using a reagent to bond the metal particles deep into the textile fibers and actually making the metal a part of the chemistry of the fiber. The chemicals of the fabric influence the resulting color. The combination of the element itself, the size of the particle, the chemical nature of the particle and the interaction of the metal with the chemistry of the fabric determine the actual hue. By using different elements, reagents, textiles and solvents a broad range of reproducible colors and tones can be created. Metals can also be combined into alloys, which will produce a variety of colors. The students of the ISCC chapter at the Fashion Institute of Technology dyed fabric using Dr. Todd's method and created a presentation of the results. They also did a demonstration of dyeing fabrics with metals.

  10. The enzymatic decolorization of textile dyes by the immobilized polyphenol oxidase from quince leaves.

    Science.gov (United States)

    Arabaci, Gulnur; Usluoglu, Ayse

    2014-01-01

    Water pollution due to release of industrial wastewater has already become a serious problem in almost every industry using dyes to color its products. In this work, polyphenol oxidase enzyme from quince (Cydonia Oblonga) leaves immobilized on calcium alginate beads was used for the successful and effective decolorization of textile industrial effluent. Polyphenol oxidase (PPO) enzyme was extracted from quince (Cydonia Oblonga) leaves and immobilized on calcium alginate beads. The kinetic properties of free and immobilized PPO were determined. Quince leaf PPO enzyme stability was increased after immobilization. The immobilized and free enzymes were employed for the decolorization of textile dyes. The dye solutions were prepared in the concentration of 100 mg/L in distilled water and incubated with free and immobilized quince (Cydonia Oblonga) leaf PPO for one hour. The percent decolorization was calculated by taking untreated dye solution. Immobilized PPO was significantly more effective in decolorizing the dyes as compared to free enzyme. Our results showed that the immobilized quince leaf PPO enzyme could be efficiently used for the removal of synthetic dyes from industrial effluents.

  11. The Enzymatic Decolorization of Textile Dyes by the Immobilized Polyphenol Oxidase from Quince Leaves

    Directory of Open Access Journals (Sweden)

    Gulnur Arabaci

    2014-01-01

    Full Text Available Water pollution due to release of industrial wastewater has already become a serious problem in almost every industry using dyes to color its products. In this work, polyphenol oxidase enzyme from quince (Cydonia Oblonga leaves immobilized on calcium alginate beads was used for the successful and effective decolorization of textile industrial effluent. Polyphenol oxidase (PPO enzyme was extracted from quince (Cydonia Oblonga leaves and immobilized on calcium alginate beads. The kinetic properties of free and immobilized PPO were determined. Quince leaf PPO enzyme stability was increased after immobilization. The immobilized and free enzymes were employed for the decolorization of textile dyes. The dye solutions were prepared in the concentration of 100 mg/L in distilled water and incubated with free and immobilized quince (Cydonia Oblonga leaf PPO for one hour. The percent decolorization was calculated by taking untreated dye solution. Immobilized PPO was significantly more effective in decolorizing the dyes as compared to free enzyme. Our results showed that the immobilized quince leaf PPO enzyme could be efficiently used for the removal of synthetic dyes from industrial effluents.

  12. Laser dye stability. Pt. 3. Bicyclic dyes in ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, A.N. (Naval Weapons Center, China Lake, Calif. (USA). Research Dept.)

    1977-11-01

    A commercial coaxial xenon flashlamp has been used to evaluate the stability of a variety of coumarin and quinolone laser dyes. The lasing characteristics of over 30 dyes have been quantitatively evaluated as a function of the total excitation energy to which recirculating dye solution has been exposed. Degradation constants were determined an an evaluation was made of the effects of functional group variation upon the stability of the dyes. Comparison with the data of other workers revealed that exclusion of excitation energy below 220 nm does not change the stability of 4-methyl coumarins, but can increase the stability of other coumarins as much as 50 fold.

  13. 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.

  14. Calcium and Mitosis

    Science.gov (United States)

    Hepler, P.

    1983-01-01

    Although the mechanism of calcium regulation is not understood, there is evidence that calcium plays a role in mitosis. Experiments conducted show that: (1) the spindle apparatus contains a highly developed membrane system that has many characteristics of sarcoplasmic reticulum of muscle; (2) this membrane system contains calcium; and (3) there are ionic fluxes occurring during mitosis which can be seen by a variety of fluorescence probes. Whether the process of mitosis can be modulated by experimentally modulating calcium is discussed.

  15. Calcium - Function and effects

    NARCIS (Netherlands)

    Liang, Jianfen; He, Yifan; Gao, Qian; Wang, Xuan; Nout, M.J.R.

    2016-01-01

    Rice is the primary food source for more than half of the world population. Levels of calcium contents and inhibitor - phytic acid are summarized in this chapter. Phytic acid has a very strong chelating ability and it is the main inhibit factor for calcium in rice products. Calcium contents in br

  16. Dye sensitized solar cells.

    Science.gov (United States)

    Wei, Di

    2010-03-16

    Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  17. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  18. Calcium signaling and epilepsy.

    Science.gov (United States)

    Steinlein, Ortrud K

    2014-08-01

    Calcium signaling is involved in a multitude of physiological and pathophysiological mechanisms. Over the last decade, it has been increasingly recognized as an important factor in epileptogenesis, and it is becoming obvious that the excess synchronization of neurons that is characteristic for seizures can be linked to various calcium signaling pathways. These include immediate effects on membrane excitability by calcium influx through ion channels as well as delayed mechanisms that act through G-protein coupled pathways. Calcium signaling is able to cause hyperexcitability either by direct modulation of neuronal activity or indirectly through calcium-dependent gliotransmission. Furthermore, feedback mechanisms between mitochondrial calcium signaling and reactive oxygen species are able to cause neuronal cell death and seizures. Unravelling the complexity of calcium signaling in epileptogenesis is a daunting task, but it includes the promise to uncover formerly unknown targets for the development of new antiepileptic drugs.

  19. Carcinogenicity of hair dye components.

    Science.gov (United States)

    Van Duuren, B L

    1980-03-01

    The available animal carcinogenicity data on hair dye components was reviewed. From this review it became clear that certain hair dye components, some of which are still in hair dye formulations now on the market, are animal carcinogens. The compounds of concern that are still in use are: 3-amino-4-methoxyaniline, 2-nitro-4-aminoaniline and 3-nitro-4-hydroxyaniline. Certain azo dyes formerly used, and related compounds still in use, contain the benzidine moiety. Two of these compounds, Direct Blue 6 and Direct Black 38, have been shown to be metabolized in animals to the human carcinogen benzidine. Furthermore, skin absorption studies carried out with radiolabeled hair dye components applied to animal or human skin have conclusively shown that these compounds are systemically absorbed and excreted. Known cocarcinogens such as catechol and pyrogallol, which enhance benzo(a)pyrene carcinogenicity on mouse skin, are used as hair dye components. It is not known whether such compounds will enhance the carcinogenicity of substituted aniline hair dye chemicals. The available epidemiologic data are not sufficient to link hair dye use with an increased incidence in human cancer.

  20. Protein-specific localization of a rhodamine-based calcium-sensor in living cells.

    Science.gov (United States)

    Best, Marcel; Porth, Isabel; Hauke, Sebastian; Braun, Felix; Herten, Dirk-Peter; Wombacher, Richard

    2016-06-28

    A small synthetic calcium sensor that can be site-specifically coupled to proteins in living cells by utilizing the bio-orthogonal HaloTag labeling strategy is presented. We synthesized an iodo-derivatized BAPTA chelator with a tetramethyl rhodamine fluorophore that allows further modification by Sonogashira cross-coupling. The presented calcium sensitive dye shows a 200-fold increase in fluorescence upon calcium binding. The derivatization with an aliphatic linker bearing a terminal haloalkane-function by Sonogashira cross-coupling allows the localization of the calcium sensor to Halo fusion proteins which we successfully demonstrate in in vitro and in vivo experiments. The herein reported highly sensitive tetramethyl rhodamine based calcium indicator, which can be selectively localized to proteins, is a powerful tool to determine changes in calcium levels inside living cells with spatiotemporal resolution.

  1. Quantitative comparison of long-wavelength Alexa Fluor dyes to Cy dyes: fluorescence of the dyes and their bioconjugates.

    Science.gov (United States)

    Berlier, Judith E; Rothe, Anca; Buller, Gayle; Bradford, Jolene; Gray, Diane R; Filanoski, Brian J; Telford, William G; Yue, Stephen; Liu, Jixiang; Cheung, Ching-Ying; Chang, Wesley; Hirsch, James D; Beechem, Joseph M; Haugland, Rosaria P; Haugland, Richard P

    2003-12-01

    Amine-reactive N-hydroxysuccinimidyl esters of Alexa Fluor fluorescent dyes with principal absorption maxima at about 555 nm, 633 nm, 647 nm, 660 nm, 680 nm, 700 nm, and 750 nm were conjugated to antibodies and other selected proteins. These conjugates were compared with spectrally similar protein conjugates of the Cy3, Cy5, Cy5.5, Cy7, DY-630, DY-635, DY-680, and Atto 565 dyes. As N-hydroxysuccinimidyl ester dyes, the Alexa Fluor 555 dye was similar to the Cy3 dye, and the Alexa Fluor 647 dye was similar to the Cy5 dye with respect to absorption maxima, emission maxima, Stokes shifts, and extinction coefficients. However, both Alexa Fluor dyes were significantly more resistant to photobleaching than were their Cy dye counterparts. Absorption spectra of protein conjugates prepared from these dyes showed prominent blue-shifted shoulder peaks for conjugates of the Cy dyes but only minor shoulder peaks for conjugates of the Alexa Fluor dyes. The anomalous peaks, previously observed for protein conjugates of the Cy5 dye, are presumably due to the formation of dye aggregates. Absorption of light by the dye aggregates does not result in fluorescence, thereby diminishing the fluorescence of the conjugates. The Alexa Fluor 555 and the Alexa Fluor 647 dyes in protein conjugates exhibited significantly less of this self-quenching, and therefore the protein conjugates of Alexa Fluor dyes were significantly more fluorescent than those of the Cy dyes, especially at high degrees of labeling. The results from our flow cytometry, immunocytochemistry, and immunohistochemistry experiments demonstrate that protein-conjugated, long-wavelength Alexa Fluor dyes have advantages compared to the Cy dyes and other long-wavelength dyes in typical fluorescence-based cell labeling applications.

  2. LIQUID DYES'CHARACTERISTICS IN DYEING WASTE PAPER PULP AND THEIR APPLICATION

    Institute of Scientific and Technical Information of China (English)

    Xiaoping Wang; gang Chen; Aimin Tang; Hongwei Zhang

    2004-01-01

    In this paper, some liquid dyes were used to dye the waste paper pulp (OCC pulp and waste cement sack paper pulp), and their dyeing characteristics were analyzed, The liquid dyes include liquid basic yellow, liquid basic blue, liquid basic red, liquid basic orange, liquid basic brown and liquid direct black. We found that, each dye had its own dyeing characteristic while dyeing the waste paper pulp.Generally different types of liquid dyes were combined to dye the waste paper pulp, which the adding process must be noticed. We also observed that a black pigment could be applied together with said liquid dyes to dye or adjust the color of the bottom sheet for the fireproof board. We could also achieve the same dyeing result through different combinations of different dyes.

  3. Calcium is important forus.

    Institute of Scientific and Technical Information of China (English)

    高利平

    2005-01-01

    Calcium is important for our health.We must have it in our diet to stay well.A good place to get it is from dairy products like milk, cheese and ice cream.One pound of cheese has fifty times the calcium we should have every day.Other foods have less.For example,a pound of beans also has calcium.But it has only three times the amount we ought to have daily.

  4. 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.

  5. 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.

  6. Survery on Actual Conditions of Food Dyes

    OpenAIRE

    佐藤,ひろみ

    1981-01-01

    Many food dyes are widely used as food additives in Japan, and many investigations have been pointed the problems of safety of these food dyes used in Japanese food. There are two types of commercial food dyes, one is synthetic dyes and the other is natural dyes.Recently Japanese food is not stained so colourfully, but it is stained faintly in colour near to natural food by using of mixed synthetic dyes. On their hand, many consumers have a tendency to prefer natural food dyes because they ha...

  7. Contact Allergy to Hair Dyes

    Directory of Open Access Journals (Sweden)

    Marie-Louise Anna Schuttelaar

    2016-06-01

    Full Text Available Many strong and extreme sensitizing chemicals, such as para-phenylenediamine (PPD, toluene-2,5-diamine (TDA and other aromatic amines or cross-reacting substances, are ingredients in hair dye products. The chemistry of hair dyeing and the immunological reactions to the potent sensitizing hair dye components are complex and have not been fully clarified up until now. Recently 2-methoxymethyl-p-phenylenediamine (ME-PPD, a PPD derivate with moderate skin-sensitizing properties, was developed. Although developed for the prevention of sensitization, ME-PPD appears to be tolerated in some PPD/TDA-allergic individuals.

  8. Dyeing Properties of Natural Dye Syzygium cuminii on Silk

    Science.gov (United States)

    Narayana Swamy, V.; Ninge Gowda, K. N.; Sudhakar, R.

    2014-04-01

    Dyeing behavior of natural dye extracted from the bark of Syzygium cuminii L has been studied on silk fabric. Colour values and colour co-ordinates were examined in terms of K/S and L* a* b* C and h. A range of shades were obtained by using various mordants and mordanting techniques. Dye was tested for some of the eco-parameters using atomic absorption spectrophotometry and GC/MS. The test results were compared with the set standards to determine the eco-friendliness of natural dye. Their concentrations were much below the stipulated limits. Dyed samples were tested for antimicrobial activity against Gram-positive and Gram-negative bacteria and were found to possess antibacterial activity.

  9. The Appetite-Inducing Peptide, Ghrelin, Induces Intracellular Store-Mediated Rises in Calcium in Addiction and Arousal-Related Laterodorsal Tegmental Neurons in Mouse Brain Slices

    DEFF Research Database (Denmark)

    Hauberg, Katrine; Kohlmeier, Kristi Anne

    2015-01-01

    Ghrelin, a gut and brain peptide, has recently been shown to be involved in motivated behavior and regulation of the sleep and wakefulness cycle. The laterodorsal tegmental nucleus (LDT) is involved in appetitive behavior and control of the arousal state of an organism, and accordingly, behavioral...... this peptide has been shown in other cell types to lead to rises in calcium via release of calcium from intracellular stores. To determine whether ghrelin induced intracellular calcium rises in mouse LDT neurons, we conducted calcium imaging studies in LDT brain slices loaded with the calcium binding dye, Fura...

  10. ATP- and gap junction-dependent intercellular calcium signaling in osteoblastic cells

    DEFF Research Database (Denmark)

    Jorgensen, N R; Geist, S T; Civitelli, R;

    1997-01-01

    mechanically induced calcium waves in two rat osteosarcoma cell lines that differ in the gap junction proteins they express, in their ability to pass microinjected dye from cell to cell, and in their expression of P2Y2 (P2U) purinergic receptors. ROS 17/2.8 cells, which express the gap junction protein...

  11. Acidosis and Urinary Calcium Excretion

    DEFF Research Database (Denmark)

    Alexander, R Todd; Cordat, Emmanuelle; Chambrey, Régine

    2016-01-01

    Metabolic acidosis is associated with increased urinary calcium excretion and related sequelae, including nephrocalcinosis and nephrolithiasis. The increased urinary calcium excretion induced by metabolic acidosis predominantly results from increased mobilization of calcium out of bone and inhibi...

  12. Relationship between nutritional habits and hair calcium levels in young women.

    Science.gov (United States)

    Jeruszka-Bielak, Marta; Brzozowska, Anna

    2011-12-01

    The present study was conducted to investigate whether hair calcium levels are related to nutritional habits, selected status parameters, and life-style factors in young women. Eighty-five healthy female students neither pregnant nor lactating, using no hair dyes or permanents were recruited for the study. Food consumption data, including fortified products and dietary supplements were collected with 4-day records. The calcium levels in hair and serum were analyzed by atomic absorption spectroscopy. Serum osteocalcin and the C-terminal telopeptide of type I collagen were assayed by ELISA. The women were divided into four groups according to their total vitamin D and calcium intakes and hair calcium levels. At adequate calcium intake and comparable serum bone biomarker levels, supplemental vitamin D increased the hair calcium levels. On the other hand, at lower than estimated adequate requirement of vitamin D intake the hair calcium levels were comparable in women with low calcium intakes but consuming high amounts of meat products or those whose diets were rich in dairy products, possibly due to homeostatic mechanisms. Elevated hair calcium was seen in 25% of subjects and could not be related to nutritional or life-style factors. The results show that the hair calcium levels were weakly related to the quality of diet, with some synergistic interactions between nutrients, especially vitamin D and magnesium.

  13. Triplet losses in dye lasers

    Energy Technology Data Exchange (ETDEWEB)

    Baczynski, A.; Kossakowski, A.; Marszalek, T. (Uniwersytet Mikolaja Kopernika, Torun (Poland). Instytut Fizyki)

    1977-01-01

    The expression for losses due to triplet states in dye laser considered as a six-level system is given. It is shown that triplet losses depend on pumping parameters and photon number. Depending on molecular and cavity parameters two differe types of behavior of dye lasers are expected. Physical conditions are discussed in which triplet losses as well as photon number undergo a jump at the threshold.

  14. Calcium signaling in neurodegeneration

    Directory of Open Access Journals (Sweden)

    Dreses-Werringloer Ute

    2009-05-01

    Full Text Available Abstract Calcium is a key signaling ion involved in many different intracellular and extracellular processes ranging from synaptic activity to cell-cell communication and adhesion. The exact definition at the molecular level of the versatility of this ion has made overwhelming progress in the past several years and has been extensively reviewed. In the brain, calcium is fundamental in the control of synaptic activity and memory formation, a process that leads to the activation of specific calcium-dependent signal transduction pathways and implicates key protein effectors, such as CaMKs, MAPK/ERKs, and CREB. Properly controlled homeostasis of calcium signaling not only supports normal brain physiology but also maintains neuronal integrity and long-term cell survival. Emerging knowledge indicates that calcium homeostasis is not only critical for cell physiology and health, but also, when deregulated, can lead to neurodegeneration via complex and diverse mechanisms involved in selective neuronal impairments and death. The identification of several modulators of calcium homeostasis, such as presenilins and CALHM1, as potential factors involved in the pathogenesis of Alzheimer's disease, provides strong support for a role of calcium in neurodegeneration. These observations represent an important step towards understanding the molecular mechanisms of calcium signaling disturbances observed in different brain diseases such as Alzheimer's, Parkinson's, and Huntington's diseases.

  15. 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.

  16. 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.

  17. LFP-guided targeting of a cortical barrel column for in vivo two-photon calcium imaging.

    Science.gov (United States)

    Lee, Joon-Hyuk; Shin, Hee-Sup; Lee, Kwang-Hyung; Chung, Sooyoung

    2015-10-29

    Two-photon microscopy of bulk-loaded functional dyes is an outstanding physiological technique that enables simultaneous functional mapping of hundreds of brain cells in vivo at single-cell resolution. However, precise targeting of a specific cortical location is not easy due to its fine dimensionality. To enable precise targeting, intrinsic-signal optical imaging is often additionally performed. However, the intrinsic-signal optical imaging is not only time-consuming but also ineffective in ensuring precision. Here, we propose an alternative method for precise targeting based on local field potential (LFP) recording, a conventional electrophysiological method. The heart of this method lies in use of the same glass pipette to record LFPs and to eject calcium dye. After confirming the target area by LFP using a glass pipette, the calcium dye is ejected from the same pipette without a time delay or spatial adjustment. As a result, the calcium dye is loaded into the same ensemble of brain cells from which the LFP was obtained. As a validation of the proposed LFP-based method, we targeted and successfully loaded calcium dye into layer 2/3 of a mouse barrel column.

  18. Ratiometric analysis of fura red by flow cytometry: a technique for monitoring intracellular calcium flux in primary cell subsets.

    Directory of Open Access Journals (Sweden)

    Emily R Wendt

    Full Text Available Calcium flux is a rapid and sensitive measure of cell activation whose utility could be enhanced with better techniques for data extraction. We describe a technique to monitor calcium flux by flow cytometry, measuring Fura Red calcium dye by ratiometric analysis. This technique has several advantages: 1 using a single calcium dye provides an additional channel for surface marker characterization, 2 allows robust detection of calcium flux by minority cell populations within a heterogeneous population of primary T cells and monocytes 3 can measure total calcium flux and additionally, the proportion of responding cells, 4 can be applied to studying the effects of drug treatment, simultaneously stimulating and monitoring untreated and drug treated cells. Using chemokine receptor activation as an example, we highlight the utility of this assay, demonstrating that only cells expressing a specific chemokine receptor are activated by cognate chemokine ligand. Furthermore, we describe a technique for simultaneously stimulating and monitoring calcium flux in vehicle and drug treated cells, demonstrating the effects of the Gαi inhibitor, pertussis toxin (PTX, on chemokine stimulated calcium flux. The described real time calcium flux assay provides a robust platform for characterizing cell activation within primary cells, and offers a more accurate technique for studying the effect of drug treatment on receptor activation in a heterogeneous population of primary cells.

  19. In vivo two-photon calcium imaging in the visual system.

    Science.gov (United States)

    Ohki, Kenichi; Reid, R Clay

    2014-04-01

    Two-photon imaging of calcium-sensitive dyes in vivo has become a common tool used by neuroscientists, largely because of the development of bolus loading techniques, which can label every neuron in a local circuit with calcium-sensitive dye. Like multielectrode recordings, two-photon imaging paired with bolus loading provides a method for monitoring many neurons at once, but, in addition, it provides a means for determining the precise location of every neuron. Thus, it is an ideal method for studying the fine-scale functional architecture of the cortex and guiding the experimenter to individual neurons that can be targeted for further anatomical study. Two-photon calcium imaging enables study of the fine structure of functional maps in the visual cortex in cats and rodents. In mice, it can allow the characterization of specific cell types when paired with transgenic or retrograde labeling.

  20. Natural dyes as photosensitizers for dye-sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Sancun; Wu, Jihuai; Huang, Yunfang; Lin, Jianming [Institute of Materials Physical Chemistry, Huaqiao University, Quanzhou, Fujian 362021 (China)

    2006-02-15

    The dye-sensitized solar cells (DSC) were assembled by using natural dyes extracted from black rice, capsicum, erythrina variegata flower, rosa xanthina, and kelp as sensitizers. The I{sub SC} from 1.142mA to 0.225mA, the V{sub OC} from 0.551V to 0.412V, the fill factor from 0.52 to 0.63, and P{sub max} from 58{mu}W to 327{mu}W were obtained from the DSC sensitized with natural dye extracts. In the extracts of natural fruit, leaves and flower chosen, the black rice extract performed the best photosensitized effect, which was due to the better interaction between the carbonyl and hydroxyl groups of anthocyanin molecule on black rice extract and the surface of TiO{sub 2} porous film. The blue-shift of absorption wavelength of the black rice extract in ethanol solution on TiO{sub 2} film and the blue-shift phenomenon from absorption spectrum to photoaction spectrum of DSC sensitized with black rice extract are discussed in the paper. Because of the simple preparation technique, widely available and low cheap cost natural dye as an alternative sensitizer for dye-sensitized solar cell is promising. (author)

  1. Discovery of Black Dye Crystal Structure Polymorphs: Implications for Dye Conformational Variation in Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Cole, Jacqueline M; Low, Kian Sing; Gong, Yun

    2015-12-23

    We present the discovery of a new crystal structure polymorph (1) and pseudopolymorph (2) of the Black Dye, one of the world's leading dyes for dye-sensitized solar cells, DSSCs (10.4% device performance efficiency). This reveals that Black Dye molecules can adopt multiple low-energy conformers. This is significant since it challenges existing models of the Black Dye···TiO2 adsorption process that renders a DSSC working electrode; these have assumed a single molecular conformation that refers to the previously reported Black Dye crystal structure (3). The marked structural differences observed between 1, 2, and 3 make the need for modeling multiple conformations more acute. Additionally, the ordered form of the Black Dye (1) provides a more appropriate depiction of its anionic structure, especially regarding its anchoring group and NCS bonding descriptions. The tendency toward NCS ligand isomerism, evidenced via the disordered form 2, has consequences for electron injection and electron recombination in Black Dye embedded DSSC devices. Dyes 2 and 3 differ primarily by the absence or presence of a solvent of crystallization, respectively; solvent environment effects on the dye are thereby elucidated. This discovery of multiple Black Dye conformers from diffraction, with atomic-level definition, complements recently reported nanoscopic evidence for multiple dye conformations existing at a dye···TiO2 interface, for a chemically similar DSSC dye; those results emanated from imaging and spectroscopy, but were unresolved at the submolecular level. Taken together, these findings lead to the general notion that multiple dye conformations should be explicitly considered when modeling dye···TiO2 interfaces in DSSCs, at least for ruthenium-based dye complexes.

  2. 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.

  3. 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...

  4. Natural Dyes as Photosensitizers for Dye-sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Hatem S. El-Ghamri

    2015-10-01

    Full Text Available Dye-sensitized solar cells (DSSCs were assembled using Zinc oxide (ZnO nanoparticles as a photoelectrode and natural dyes extracted from eight natural plants as photosensitizers. The structural properties of the synthesized ZnO nanoparticles were studied using XRD, SEM and TEM characterizations. Photovoltaic parameters such as short circuit current density Jsc, open circuit voltage Voc, fill factor FF, and overall conversion efficiency η for the fabricated cells were determined under 100 mW/cm2 illumination. It was found that the DSSC fabricated with the extracted safflower dye as a sensitizer showed the best performance. Also, its performance increased with increasing the sintering temperature of the semiconductor electrode with highest performance at 400 °C. Moreover, it was found that a semiconductor electrode of 7.5 μm thickness yielded the highest response.

  5. Laser dye toxicity, hazards, and recommended controls

    Energy Technology Data Exchange (ETDEWEB)

    Mosovsky, J.A.

    1983-05-06

    Laser dyes are complex fluorescent organic compounds which, when in solution with organic solvents, form a lasing medium. The wavelength of a dye laser's output beam can vary with different dyes, concentrations, and solvents, giving it a tunable feature capable of emitting ultraviolet, visible, or infrared radiation. Toxicity information on the approximately 100 commercially available laser dyes is very scarce. Limited animal experimentation has been performed with only a few dyes. This paper summarizes what is known about laser dye toxicity, and offers recommendations for controlling dye hazards. The laser dyes investigated have been categorized according to their central chemical structures. These include the xanthenes (rhodamines and fluoresceins), polymethines (cyanines and carbocyanines), coumarins, and stilbenes. A few other miscellaneous dyes that do not fall into one of these categories have also been investigated. Prepared laser dye solutions usually contain very small quantities of dye--typical dye concentrations are 10/sup -2/ to 10/sup -5/ molar. For this reason, the solvent in which the dye is dissolved plays an important role when defining potential hazards. Practically all the solvents used are flammable and toxic by inhalation and skin absorption, and therefore must be controlled properly.

  6. Assessment of alginate hydrogel degradation in biological tissue using viscosity-sensitive fluorescent dyes

    Science.gov (United States)

    Shkand, Tatiana V.; Chizh, Mykola O.; Sleta, Iryna V.; Sandomirsky, Borys P.; Tatarets, Anatoliy L.; Patsenker, Leonid D.

    2016-12-01

    The main goal of this study is to investigate a combination of viscosity-sensitive and viscosity-insensitive fluorescent dyes to distinguish different rheological states of hydrogel based biostructural materials and carriers in biological tissues and to assess their corresponding location areas. The research is done in the example of alginate hydrogel stained with viscosity-sensitive dyes Seta-470 and Seta-560 as well as the viscosity-insensitive dye Seta-650. These dyes absorb/emit at 469/518, 565/591 and 651/670 nm, respectively. The rheological state of the alginate, the area of the fluorescence signal and the mass of the dense alginate versus the calcium gluconate concentration utilized for alginate gelation were studied in vitro. The most pronounced change in the fluorescence signal area was found at the same concentrations of calcium gluconate (below ~1%) as the change in the alginate plaque mass. The stained alginate was also implanted in situ in rat hip and myocardium and monitored using fluorescence imaging. In summary, our data indicate that the viscosity sensitive dye in combination with the viscosity-insensitive dye allow tracking the biodegradation of the alginate hydrogel and determining the rheological state of hydrogel in biological tissue, which both should have relevance for research and clinical applications. Using this method we estimated the half-life of the dense alginate hydrogel in a rat hip to be in the order of 4 d and about 6-8 d in rat myocardium. The half-life of the dense hydrogel in the myocardium was found to be long enough to prevent aneurysm rupture of the left ventricle wall, one of the more severe complications of the early post-infarction period.

  7. A novel, rapid method to quantify intraplatelet calcium dynamics by ratiometric flow cytometry.

    Directory of Open Access Journals (Sweden)

    Alice Assinger

    Full Text Available Cytosolic free calcium ions represent important second-messengers in platelets. Therefore, quantitative measurement of intraplatelet calcium provides a popular and very sensitive tool to evaluate platelet activation and reactivity. Current protocols for determination of intracellular calcium concentrations in platelets have a number of limitations. Cuvette-based methods do not allow measurement of calcium flux in complex systems, such as whole blood, and therefore require isolation steps that potentially interfere with platelet activation. Flow cytometry has the potential to overcome this limitation, but to date the application of calibrated, quantitative readout of calcium kinetics has only been described for Indo-1. As excitation of Indo-1 requires a laser in the ultraviolet range, such measurements cannot be performed with a standard flow cytometer. Here, we describe a novel, rapid calibration method for ratiometric calcium measurement in platelets using both Ar(+-laser excited fluorescence dyes Fluo-4 and Fura Red. We provide appropriate equations that allow rapid quantification of intraplatelet calcium fluxes by measurement of only two standardisation buffers. We demonstrate that this method allows quantitative calcium measurement in platelet rich plasma as well as in whole blood. Further, we show that this method prevents artefacts due to platelet aggregate formation and is therefore an ideal tool to determine basal and agonist induced calcium kinetics.

  8. Calcium and Your Child

    Science.gov (United States)

    ... for dinner. Create mini-pizzas by topping whole-wheat English muffins or bagels with pizza sauce, low- ... Minerals Do I Need to Drink Milk? Lactose Intolerance Becoming a Vegetarian Soy Foods and Health Calcium ...

  9. Stoichiometry of Calcium Medicines

    Science.gov (United States)

    Pinto, Gabriel

    2005-01-01

    The topic of calcium supplement and its effects on human lives is presented in the way of questions to the students. It enables the students to realize the relevance of chemistry outside the classroom surrounding.

  10. Calcium and Calcium-Base Alloys

    Science.gov (United States)

    1949-01-01

    should be satisfactory, because the electrolytic process for •(!>: A. H. Everts and G. D. Baglev’, " Physical «nrt m<„.+„4 i «_ of Calcium«, Electrochem...Rev. Metalurgie , 3j2, (1), 129 (1935). 10 ^sm^mssss^ma^^ extension between two known loads, is preferable to the value of 3,700,000 p.B.i. obtained

  11. Calcium imaging of infrared-stimulated activity in rodent brain.

    Science.gov (United States)

    Cayce, Jonathan Matthew; Bouchard, Matthew B; Chernov, Mykyta M; Chen, Brenda R; Grosberg, Lauren E; Jansen, E Duco; Hillman, Elizabeth M C; Mahadevan-Jansen, Anita

    2014-04-01

    Infrared neural stimulation (INS) is a promising neurostimulation technique that can activate neural tissue with high spatial precision and without the need for exogenous agents. However, little is understood about how infrared light interacts with neural tissue on a cellular level, particularly within the living brain. In this study, we use calcium sensitive dye imaging on macroscopic and microscopic scales to explore the spatiotemporal effects of INS on cortical calcium dynamics. The INS-evoked calcium signal that was observed exhibited a fast and slow component suggesting activation of multiple cellular mechanisms. The slow component of the evoked signal exhibited wave-like properties suggesting network activation, and was verified to originate from astrocytes through pharmacology and 2-photon imaging. We also provide evidence that the fast calcium signal may have been evoked through modulation of glutamate transients. This study demonstrates that pulsed infrared light can induce intracellular calcium modulations in both astrocytes and neurons, providing new insights into the mechanisms of action of INS in the brain.

  12. Textile dyeing by dyestuffs of natural origin

    Directory of Open Access Journals (Sweden)

    Šmelcerović Miodrag

    2006-01-01

    Full Text Available The textile industry is one of the biggest industrial consumers of water especially dye houses which utilize synthetic dyes and other chemicals. Natural dyes are generally environmental friendly and have many advantages over synthetic dyes with respect to production and application. In recent years, there has been an interest in the application of these dyes due to their bio-degradability and higher compatibility with the environment. A review of previous work in the field of applying dyestuffs of natural source as possible textile dyes is given. From an ecological viewpoint, the substitution of chemical dyes by 'natural products' in textile dyeing may be feasible and may represent not only a strategy to reduce risks and pollutants, but also an opportunity for new markets and new businesses which can develop from the inclusion of ecology in trade policy.

  13. Triarylmethane Dyes for Artificial Repellent Cotton Fibers.

    Science.gov (United States)

    Montagut, Ana Maria; Gálvez, Erik; Shafir, Alexandr; Sebastián, Rosa María; Vallribera, Adelina

    2017-03-17

    Families of new hydrophobic and/or oleophobic triarylmethane dyes possessing long hydrocarbon or polyfluorinated chains have been prepared. When covalently grafted on to cotton fabric, these dyes give rise to a new type of colored superhydrophobic fibers.

  14. Dye Sensitized Tandem Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Greg D.

    2009-12-21

    This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.

  15. Dye Sysentized Solar Cell (Dyssc

    Directory of Open Access Journals (Sweden)

    A. Dileep,

    2015-11-01

    Full Text Available This paper presents a Dye sensitized solar cell (DYSSC, which is called as future generation solar cell. It is a new class of green photovoltaic cell based on photosynthesis principle in nature. DYSSCs are fabricated using two different natural dyes as sensitizers, which extracted from the materials existing in nature and our life, such as flowers, leaves, fruits, traditional Chinese medicines, and beverages. The use of sensitizers having a broad absorption band in conjunction with oxide films of nanocrystalline morphology permits to harvest a large fraction of sunlight. There are good prospects to produce these cells at lower cost and much better efficiency than conventional semiconductor devices by introducing various chemical and natural dyes. DYSSC are implemented with simple and new technique to overcome the energy crisis and excess cost of semiconductor solar cells.

  16. Dye solubility in supercritical carbon dioxide fluid

    Directory of Open Access Journals (Sweden)

    Yan Jun

    2015-01-01

    Full Text Available Supercritical carbon dioxide fluid is an alternative solvent for the water of the traditional dyeing. The solubility of dyestuff affects greatly the dyeing process. A theoretical model for predicting the dye solubility is proposed and verified experimentally. The paper concludes that the pressure has a greater impact on the dyestuff solubility than temperature, and an optimal dyeing condition is suggested for the highest distribution coefficient of dyestuff.

  17. Fong’s: Saving Water in Dyeing

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In an effort to save the precious water resource and reduce the environmental impact, Fong’s Industries Group along with its member companies, namely "Fong’s National", "THEN", "Goller" and "Fong’s Water Technology" provide an ecological dyeing solution to reduce the water consumption drastically through their innovative technologies covering the processes from yarn dyeing to piece dyeing and recycling of discharge after dyeing and finishing.

  18. Water in supercritical carbon dioxide dyeing

    Directory of Open Access Journals (Sweden)

    Zheng Lai-Jiu

    2015-01-01

    Full Text Available This paper investigates the effect of water serving as entrainer on the dyeing of wool fabrics in supercritical carbon dioxide. Compared with previous supercritical dyeing methods, addition of water makes the dyeing process more effective under low temperature and low pressure. During dyeing process, dyestuff can be uniformly distributed on fabrics’s surface due to water interaction, as a result coloration is enhanced while color difference is decreased.

  19. Effect of dye structure and redox mediators on anaerobic azo and anthraquinone dye reduction

    Directory of Open Access Journals (Sweden)

    Mayara Carantino Costa

    2012-01-01

    Full Text Available We investigated the biological decolourisation of dyes with different molecular structures. The kinetic constant values (k1 achieved with azo dye Reactive Red 120 were 7.6 and 10.1 times higher in the presence of RM (redox mediators AQDS and riboflavin, respectively, than the assays lacking RM. The kinetic constant achieved with the azo dye Congo Red was 42 times higher than that obtained with the anthraquinone dye Reactive Blue 4. The effect of RM on dye reduction was more evident for azo dyes resistant to reductive processes, and ineffective for anthraquinone dyes because of the structural stability of the latter.

  20. 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.

  1. [Calcium suppletion for patients who use gastric acid inhibitors: calcium citrate or calcium carbonate?].

    NARCIS (Netherlands)

    Jonge, H.J. de; Gans, R.O.; Huls, G.A.

    2012-01-01

    Various calcium supplements are available for patients who have an indication for calcium suppletion. American guidelines and UpToDate recommend prescribing calcium citrate to patients who use antacids The rationale for this advice is that water-insoluble calcium carbonate needs acid for adequate ab

  2. Calcium homeostasis in barley aleurone

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R.L.

    1990-02-21

    Under the auspices of the Department of Energy we investigated calcium homeostasis in aleurone cells of barley. This investigation was initiated to explore the role played by extracellular Ca{sup 2+} in gibberellic acid (GA)-induced synthesis and secretion of hydrolases in the aleurone layer. We have focused our attention on four topics that relate to the role of Ca{sup 2+} in regulating the synthesis of {alpha}-amylase. First, we determined the stoichiometry of Ca{sup 2+} binding to the two principal classes of barley {alpha}-amylase and examined some of the biochemical and physical properties of the native and Ca{sup 2+}-depleted forms of the enzyme. Second, since {alpha}-amylase is a Ca{sup 2+} containing metalloenzyme that binds one atom of Ca{sup 2+} per molecule, we developed methods to determine the concentration of Ca{sup 2+} in the cytosol of the aleurone cell. We developed a technique for introducing Ca{sup 2+}-sensitive dyes into aleurone protoplasts that allows the measurement of Ca{sup 2+} in both cytosol and endoplasmic reticulum (ER). Third, because the results of our Ca{sup 2+} measurements showed higher levels of Ca{sup 2+} in the ER than in the cytosol, we examined Ca{sup 2+} transport into the ER of control and GA-treated aleurone tissue. And fourth, we applied the technique of patch-clamping to the barley aleurone protoplast to examine ion transport at the plasma membrane. Our results with the patch-clamp technique established the presence of K{sup +} channels in the plasma membrane of the aleurone protoplast, and they showed that this cell is ideally suited for the application of this methodology for studying ion transport. 34 refs.

  3. Natural dyes versus lysochrome dyes in cheiloscopy: A comparative evaluation

    Directory of Open Access Journals (Sweden)

    Narendra Nath Singh

    2010-01-01

    Full Text Available Cheiloscopy is the study of lip prints. Lip prints are genotypically determined and are unique, and stable. At the site of crime, lip prints can be either visible or latent. To develop lip prints for study purpose various chemicals such as lysochrome dyes, fluorescent dyes, etc. are available which are very expensive. Vermilion (Sindoor used by married Indian women and indigo dye (fabric whitener are readily available, naturally derived, and cost-effective reagents available in India. Objective: To compare the efficacy of sudan black, vermilion, and indigo in developing visible and latent lip prints made on bone china cup, satin fabric, and cotton fabric. Materials and Methods: Out of 45 Volunteers 15 lip prints were made on bone China cup 15 lip prints on Satin fabric and 15 on Cotton fabric. Sudan black, vermilion and indigo were applied on visible and latent lip prints and graded as good (+,+, fair (+, and poor (- and statistically evaluated. Results: The vermilion and indigo dye gives comparable results to that of sudan black for developing visible and latent lip prints.

  4. Synthesis and dyeing performance of a novel polycarboxylic acid azo dye

    Institute of Scientific and Technical Information of China (English)

    Hua Xu; Bing Tao Tang; Shu Fen Zhang

    2011-01-01

    A novel reactive polycarboxylic acid dye was synthesized by the reaction of polymaleic anhydride (PMA) with 3-methyl-l-(4-sulfonylphenyl)-4-(4-aminophenylazo)-2-pyrazoline-5-one. The structure of the novel dye was characterized by FTIR, UV-vis and 13C NMR spectra. The dyeing properties of dye on cotton were tested, and the novel dye possessed high fixation and good fastness.

  5. Descoloration of industrial dyes and simulated textile effluents dyes by turnip peroxidase

    OpenAIRE

    Silva,Maria Cristina; Angelita D Corrêa; Torres, Juliana A.; Amorim, M. T. Pessoa de

    2012-01-01

    The removal of important textile dyes by turnip peroxidase (TNP) was evaluated. The textile effluents besides the residual dyes contain also chemical auxiliaries such as salts, dispersing and wetting agents. The effect of these was evaluated in the removal of the dyes reactive blue 21 and reactive blue 19 by TNP in synthetic effluents. A decrease of the efficency decolorization was observed. The action of the enzyme on colour removal of dye mixture was equivalent to the dyes alone. The chemic...

  6. Calcium in plant cells

    Directory of Open Access Journals (Sweden)

    V. V. Schwartau

    2014-04-01

    Full Text Available The paper gives the review on the role of calcium in many physiological processes of plant organisms, including growth and development, protection from pathogenic influences, response to changing environmental factors, and many other aspects of plant physiology. Initial intake of calcium ions is carried out by Ca2+-channels of plasma membrane and they are further transported by the xylem owing to auxins’ attractive ability. The level of intake and selectivity of calcium transport to ove-ground parts of the plant is controlled by a symplast. Ca2+enters to the cytoplasm of endoderm cells through calcium channels on the cortical side of Kaspary bands, and is redistributed inside the stele by the symplast, with the use of Ca2+-АТPases and Ca2+/Н+-antiports. Owing to regulated expression and activity of these calcium transporters, calclum can be selectively delivered to the xylem. Important role in supporting calcium homeostasis is given to the vacuole which is the largest depo of calcium. Regulated quantity of calcium movement through the tonoplast is provided by a number of potential-, ligand-gated active transporters and channels, like Ca2+-ATPase and Ca2+/H+ exchanger. They are actively involved in the inactivation of the calcium signal by pumping Ca2+ to the depo of cells. Calcium ATPases are high affinity pumps that efficiently transfer calcium ions against the concentration gradient in their presence in the solution in nanomolar concentrations. Calcium exchangers are low affinity, high capacity Ca2+ transporters that are effectively transporting calcium after raising its concentration in the cell cytosol through the use of protons gradients. Maintaining constant concentration and participation in the response to stimuli of different types also involves EPR, plastids, mitochondria, and cell wall. Calcium binding proteins contain several conserved sequences that provide sensitivity to changes in the concentration of Ca2+ and when you

  7. Elemental calcium intake associated with calcium acetate/calcium carbonate in the treatment of hyperphosphatemia

    OpenAIRE

    Wilson, Rosamund J; Copley, J Brian

    2017-01-01

    Background Calcium-based and non-calcium-based phosphate binders have similar efficacy in the treatment of hyperphosphatemia; however, calcium-based binders may be associated with hypercalcemia, vascular calcification, and adynamic bone disease. Scope A post hoc analysis was carried out of data from a 16-week, Phase IV study of patients with end-stage renal disease (ESRD) who switched to lanthanum carbonate monotherapy from baseline calcium acetate/calcium carbonate monotherapy. Of the intent...

  8. [Microbial geochemical calcium cycle].

    Science.gov (United States)

    Zavarzin, G A

    2002-01-01

    The participation of microorganisms in the geochemical calcium cycle is the most important factor maintaining neutral conditions on the Earth. This cycle has profound influence on the fate of inorganic carbon, and, thereby, on the removal of CO2 from the atmosphere. The major part of calcium deposits was formed in the Precambrian, when prokaryotic biosphere predominated. After that, calcium recycling based on biogenic deposition by skeletal organisms became the main process. Among prokaryotes, only a few representatives, e.g., cyanobacteria, exhibit a special calcium function. The geochemical calcium cycle is made possible by the universal features of bacteria involved in biologically mediated reactions and is determined by the activities of microbial communities. In the prokaryotic system, the calcium cycle begins with the leaching of igneous rock predominantly through the action of the community of organotrophic organisms. The release of carbon dioxide to the soil air by organotrophic aerobes leads to leaching with carbonic acid and soda salinization. Under anoxic conditions, of major importance is the organic acid production by primary anaerobes (fermentative microorganisms). Calcium carbonate is precipitated by secondary anaerobes (sulfate reducers) and to a smaller degree by methanogens. The role of the cyanobacterial community in carbonate deposition is exposed by stromatolites, which are the most common organo-sedimentary Precambrian structures. Deposition of carbonates in cyanobacterial mats as a consequence of photoassimilation of CO2 does not appear to be a significant process. It is argued that carbonates were deposited at the boundary between the "soda continent", which emerged as a result of subaerial leaching with carbonic acid, and the ocean containing Ca2+. Such ecotones provided favorable conditions for the development of the benthic cyanobacterial community, which was a precursor of stromatolites.

  9. Preparation of a Novel Chitosan Based Biopolymer Dye and Application in Wood Dyeing

    Directory of Open Access Journals (Sweden)

    Xiaoqian Wang

    2016-09-01

    Full Text Available A novel chitosan-based biopolymer dye possessing antibacterial properties was synthesized by reaction of O-carboxymethyl chitosan and Acid Red GR. The synthesized materials were characterized by Fourier transform infrared spectroscopy (FTIR, degree of substitution (DS, X-ray photoelectron spectroscopy (XPS, thermogravimetric analysis (TG, X-ray diffraction (XRD, water solubility test, antibacterial property test, and dyeing performance, including dye uptake, color difference, and fastness. Results showed that the synthesized dye was combined by –NH3+ of O-carboxymethyl chitosan and the sulfonic group of Acid Red GR. According to the comprehensive analysis of XRD and water solubility, the introduction of the carboxymethyl group and acid dye molecule changed the structure of the chitosan from compact to loose, which improved the synthesized dye’s water solubility. However, the thermal stability of the synthesized dye was decreased. The antibacterial property of the poplar wood dyed with the synthesized dye was enhanced and its antibacterial rate, specifically against Staphylococcus aureus and Escherichia coli, also increased to a rate of more than 99%. However, the dye uptake of the synthesized dye was lower than that of the original dye. Despite this, though, the dyeing effect of the synthesized dye demonstrated better water-fastness, and light-fastness than the original dye. Therefore, the novel chitosan-based biopolymer dye can be a promising product for wood dyeing.

  10. 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.

  11. Hair Dyes and Cancer Risk

    Science.gov (United States)

    ... dye use and bladder cancer: a meta-analysis. Annals of Epidemiology 2014; 24(2),151–159. [PubMed ... in a prospective cohort of Chinese women. Cancer Science 2009; 100(6):1088-1091. [PubMed Abstract] Related ...

  12. Anthraquinone dyes for superhydrophobic cotton.

    Science.gov (United States)

    Salabert, J; Sebastián, R M; Vallribera, A

    2015-09-28

    Water-repellent, self-cleaning and stain resistant textiles are of interest for industrial applications. Anthraquinone reactive dyes were covalently grafted onto cotton fabric surfaces obtaining bright colors with good wash-fastness properties and giving rise to breathable superhydrophobic textiles with self-cleaning properties.

  13. Waste Water Treatment of Dye Contamination

    OpenAIRE

    Pattana Boonyaprapa

    2009-01-01

    The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment s...

  14. Inositol trisphosphate and calcium signalling

    Science.gov (United States)

    Berridge, Michael J.

    1993-01-01

    Inositol trisphosphate is a second messenger that controls many cellular processes by generating internal calcium signals. It operates through receptors whose molecular and physiological properties closely resemble the calcium-mobilizing ryanodine receptors of muscle. This family of intracellular calcium channels displays the regenerative process of calcium-induced calcium release responsible for the complex spatiotemporal patterns of calcium waves and oscillations. Such a dynamic signalling pathway controls many cellular processes, including fertilization, cell growth, transformation, secretion, smooth muscle contraction, sensory perception and neuronal signalling.

  15. [Leather azo dyes: mutagenic and carcinogenic risks].

    Science.gov (United States)

    Clonfero, E; Venier, P; Granella, M; Levis, A G

    1990-01-01

    The paper reviews the carcinogenicity and mutagenicity data on azo dyes used in the leather industry. Two water soluble benzidine-based dyes were classified as "probably carcinogenic to humans" by the International Agency for Research on Cancer (IARC). No other dyes have been evaluated by the IARC. Of the 48 azo dyes assayed in the Salmonella/microsome test, 20 gave positive results. Attention is drawn to the important role of the in vivo metabolism of azo compounds, which includes a preliminary reduction of the azo bonds and subsequent release of the aromatic amines of the dye. A useful assay (Prival test) for evaluating the mutagenic properties of azo dyes involves a reductive step that permits the release of any genotoxic agents present in the compounds. A list of leather azo dyes is furnished that are considered as potentially harmful due to the presence of a carcinogenic aromatic amine (benzidine, p-aminobenzene and derivatives) in their formulae.

  16. The effect of compressive loading magnitude on in situ chondrocyte calcium signaling.

    Science.gov (United States)

    Madden, Ryan M J; Han, Sang-Kuy; Herzog, Walter

    2015-01-01

    Chondrocyte metabolism is stimulated by deformation and is associated with structural changes in the cartilage extracellular matrix (ECM), suggesting that these cells are involved in maintaining tissue health and integrity. Calcium signaling is an initial step in chondrocyte mechanotransduction that has been linked to many cellular processes. Previous studies using isolated chondrocytes proposed loading magnitude as an important factor regulating this response. However, calcium signaling in the intact cartilage differs compared to isolated cells. The purpose of this study was to investigate the effect of loading magnitude on chondrocyte calcium signaling in intact cartilage. We hypothesized that the percentage of cells exhibiting at least one calcium signal increases with increasing load. Fully intact rabbit femoral condyle and patellar bone/cartilage samples were incubated in calcium-sensitive dyes and imaged continuously under compressive loads of 10-40 % strain. Calcium signaling was primarily associated with the dynamic loading phase and greatly increased beyond a threshold deformation of about 10 % nominal tissue strain. There was a trend toward more cells exhibiting calcium signaling as loading magnitude increased (p = 0.133). These results provide novel information toward identifying mechanisms underlying calcium-dependent signaling pathways related to cartilage homeostasis and possibly the onset and progression of osteoarthritis.

  17. Gravimetric Determination of Calcium as Calcium Carbonate Hydrate.

    Science.gov (United States)

    Henrickson, Charles H.; Robinson, Paul R.

    1979-01-01

    The gravimetric determination of calcium as calcium carbonate is described. This experiment is suitable for undergraduate quantitative analysis laboratories. It is less expensive than determination of chloride as silver chloride. (BB)

  18. Calcium and Calcium Supplements: Achieving the Right Balance

    Science.gov (United States)

    ... bone mass, which is a risk factor for osteoporosis. Many Americans don't get enough calcium in their diets. Children and adolescent girls are at particular risk, but so are adults age 50 and older. How much calcium you ...

  19. Dyeing of Jute with Reactive Dyes: Optimisation of the Process Variables and Assessment of Colourfastness Characteristics

    Science.gov (United States)

    Samanta, A. K.; Chakraborty, Sharmistha; Guha Roy, T. K.

    2012-08-01

    This paper deals with the studies on the effect of dye concentration, electrolyte (common salt) concentration, dyeing time, dyeing temperature, soda ash concentration, pH of the dye solution and material to liquor ratio (MLR) on colour strength and other colour parameters after being dyed of jute fabrics with reactive dyes, namely, Turquoise blue, Lemon Yellow, Red CN colours. The dye absorption increases with increase in electrolyte (common salt) concentration, dyeing time, dyeing temperature, soda ash concentration, pH and decreases with increase of MLR. Colour fastness to wash, light and rubbing for the dyed samples has been studied and reported. It is observed that reactive dye gives overall good colour fastness to both washing and rubbing. But the light fastness has been found to be moderate only, due to the UV-light initiated fading of jute fibre itself change of the colour substrate, ie, undyed material. This colour fastness has been significantly resolved by post treatment with 1 % benzotriazole.

  20. Dyeing of Polyester Woven Fabric with Disperse Dye Using Conventional and Microwave Technique

    Directory of Open Access Journals (Sweden)

    Uzma Syed

    2014-07-01

    Full Text Available Polyester fabric is generally dyed using high temperature dyeing technique and carrier. Both techniques require high energy consumption while few carriers are toxic in nature. In this study, 100% polyester woven fabric was dyed by microwave and conventional dyeing technique with disperse dye; Foron Blue RD GLN by an exhaust method for short dyeing cycle (15 and 30 min. The fabric samples were dyed using conventional high temperature dyeing technique using recommended recipe. Moreover, samples were also dyed using microwave technique with recommended recipe and by the addition of salt and urea, pre-treatment with caustic and organic solvent for improving the dye uptake value and fastness properties. The dyeing assessment; (K/S?max value by Datacolor spectrophotometer, dye uniformity by optical microscope and washing fastness by grey scale were measured. It has been observed that over conventional dyeing method, microwave irradiation dyed sample gives almost 70% high (K/S?max value and uniform dye penetration and good to very good washing fastness property. In addition, microwave dyeing gives excellent dyeing behavior at short dyeing cycle; 15 min; hence saves energy and sustainable dyeing process

  1. Calcium, vitamin D and bone

    OpenAIRE

    Borg, Andrew A.

    2012-01-01

    Calcium, protein and vitamin D are the main nutrients relevant to bone health. This short article discusses the importance of vitamin D and its relation to calcium homeostasis. The various causes, clinical manifestations and treatment are outlined.

  2. 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.

  3. Artificial evolution of coumarin dyes for dye sensitized solar cells.

    Science.gov (United States)

    Venkatraman, Vishwesh; Abburu, Sailesh; Alsberg, Bjørn Kåre

    2015-11-07

    The design and discovery of novel molecular structures with optimal properties has been an ongoing effort for materials scientists. This field has in general been dominated by experiment driven trial-and-error approaches that are often expensive and time-consuming. Here, we investigate if a de novo computational design methodology can be applied to the design of coumarin-based dye sensitizers with improved properties for use in Grätzel solar cells. To address the issue of synthetic accessibility of the designed compounds, a fragment-based assembly is employed, wherein the combination of chemical motifs (derived from the existing databases of structures) is carried out with respect to user-adaptable set of rules. Rather than using computationally intensive density functional theory (DFT)/ab initio methods to screen candidate dyes, we employ quantitative structure-property relationship (QSPR) models (calibrated from empirical data) for rapid estimation of the property of interest, which in this case is the product of short circuit current (Jsc) and open circuit voltage (Voc). Since QSPR models have limited validity, pre-determined applicability domain criteria are used to prevent unacceptable extrapolation. DFT analysis of the top-ranked structures provides supporting evidence of their potential for dye sensitized solar cell applications.

  4. Calcium ion channel and epilepsy

    Institute of Scientific and Technical Information of China (English)

    Yudan Lü; Weihong Lin; Dihui Ma

    2006-01-01

    OBJECTIVE: To review the relationship between calcium ion channel and epilepsy for well investigating the pathogenesis of epilepsy and probing into the new therapeutic pathway of epilepsy.DATA SOURCES: A computer-based online research Calcium ion channel and epilepsy related articles published between January 1994 and December 2006 in the CKNI and Wanfang database with the key words of "calcium influxion, epilepsy, calcium-channel blocker". The language was limited to Chinese. At the same time,related articles published between January 1993 and December 2006 in Pubmed were searched for on online with the key words of "calcium influxion, epilepsy" in English.STUDY SELECTION: The materials were selected firstly. Inclusive criteria: ① Studies related to calcium ion channel and the pat1hogenesis of epilepsy. ② Studies on the application of calcium ion channel blocker in the treatment of epilepsy. Exclusive criteria: repetitive or irrelated studies.DATA EXTRACTION: According to the criteria, 123 articles were retrieved and 93 were excluded due to repetitive or irrelated studies. Altogether 30 articles met the inclusive criteria, 11 of them were about the structure and characters of calcium ion channel, 10 about calcium ion channel and the pathogenesis of epilepsy and 9 about calcium blocker and the treatment of epilepsy.DATA SYNTHESIS: Calcium ion channels mainly consist of voltage dependent calcium channel and receptor operated calcium channel. Depolarization caused by voltage gating channel-induced influxion is the pathological basis of epileptic attack, and it is found in many studies that many anti-epileptic drugs have potential and direct effect to rivalizing voltage-dependent calcium ion channel.CONCLUSION: Calcium influxion plays an important role in the seizure of epilepsy. Some calcium antagonists seen commonly are being tried in the clinical therapy of epilepsy that is being explored, not applied in clinical practice. If there are enough evidences to

  5. [Benzidine dyes and risk of bladder cancer].

    Science.gov (United States)

    Miyakawa, M; Yoshida, O

    1989-12-01

    Until the early 1970's there was little concern about dyes which contain benzidine as an integral part of their chemical structure. Furthermore, use of the finished dyes was not considered dangerous. To ascertain whether azo dyes are associated with risk of development of bladder tumors in workers who handpaint Yuzen-type silk kimonos in Kyoto, we investigated the disintegration of dyes to benzidine. In these studies, we found that in rats and mice benzidine-based dyes are metabolized to benzidine and that the azo linkage of benzidine dyes is reduced by Escherichia coli and soil bacteria. These experimental findings were reported previously. In this report, we outline an approach to these studies. Many of the dyes used to color paper, textiles, lipstick, bait used by fishermen, as well as hair dyes, and dyes used in research, for pharmaceutical products, and by defence personnel for the detection of liquid chemical warfare agents, have been shown to be potentially mutagenic or carcinogenic. We review the literature on these dyes.

  6. Calcium carbonate overdose

    Science.gov (United States)

    Calcium carbonate is not very poisonous. Recovery is quite likely. But, long-term overuse is more serious than a single overdose, because it can cause kidney damage. Few people die from an antacid overdose. Keep all medicines in child-proof bottles and out ...

  7. High Blood Calcium (Hypercalcemia)

    Science.gov (United States)

    ... as well as kidney function and levels of calcium in your urine. Your provider may do other tests to further assess your condition, such as checking your blood levels of phosphorus (a mineral). Imaging studies also may be helpful, such as bone ...

  8. Solar Imagery - Chromosphere - Calcium

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of full-disk images of the sun in Calcium (Ca) II K wavelength (393.4 nm). Ca II K imagery reveal magnetic structures of the sun from about 500...

  9. Calcium imaging of individual erythrocytes: problems and approaches.

    Science.gov (United States)

    Kaestner, Lars; Tabellion, Wiebke; Weiss, Erwin; Bernhardt, Ingolf; Lipp, Peter

    2006-01-01

    Although in erythrocytes calcium is thought to be important in homeostasis, measurements of this ion concentration are generally seen as rather problematic because of the auto-fluorescence or absorption properties of the intracellular milieu. Here, we describe experiments to assess the usability of popular calcium indicators such as Fura-2, Indo-1 and Fluo-4. In our experiments, Fluo-4 turned out to be the preferable indicator because (i) its excitation and emission properties were least influenced by haemoglobin and (ii) it was the only dye for which excitation light did not lead to significant auto-fluorescence of the erythrocytes. From these results, we conclude that the use of indicators such as Fura-2 together with red blood cells has to be revisited critically. We thus utilized Fluo-4 in erythrocytes to demonstrate a robust but heterogeneous calcium increase in these cells upon stimulation by prostaglandin E(2) and lysophosphatidic acid. For the latter stimulus, we recorded emission spectra of individual erythrocytes to confirm largely unaltered Fluo-4 emission. Our results emphasize that in erythrocytes measurements of intracellular calcium are reliably possible with Fluo-4 and that other indicators, especially those requiring UV-excitation, appear less favourable.

  10. Synthesis, characterization and dyeing behavior of heterocyclic acid dyes and mordent acid dyes on wool and silk fabrics

    Directory of Open Access Journals (Sweden)

    Patel Hitendra M.

    2012-01-01

    Full Text Available Novel heterocyclic acid and mordent acid dyes were synthesized by the coupling of diazonium salt solution of different aromatic amines with 2- butyl-3-(4-hydroxybenzoylbenzofuran. The resulting heterocyclic acid dyes were characterized by spectral techniques, i.e., elemental analysis, IR, 1HNMR, 13C-NMR spectral studies and UV- visible spectroscopy. The dyeing performance of all the heterocyclic acid dyes was evaluated on wool and silk fabrics. The dyeing of chrome pre treated wool and silk fabrics showed better hues on mordented fabrics. Dyeing of wool and silk fabrics resulted in pinkish blue to red shades with very good depth and levelness. The dyed fabrics showed excellent to very good light, washing, perspiration, sublimation and rubbing fastness.

  11. Calcium aluminate in alumina

    Science.gov (United States)

    Altay, Arzu

    The properties of ceramic materials are determined not only by the composition and structure of the phases present, but also by the distribution of impurities, intergranular films and second phases. The phase distribution and microstructure both depend on the fabrication techniques, the raw materials used, the phase-equilibrium relations, grain growth and sintering processes. In this dissertation research, various approaches have been employed to understand fundamental phenomena such as grain growth, impurity segregation, second-phase formation and crystallization. The materials system chosen was alumina intentionally doped with calcium. Atomic-scale structural analyses of grain boundaries in alumina were carried on the processed samples. It was found that above certain calcium concentrations, CA6 precipitated as a second phase at all sintering temperatures. The results also showed that abnormal grain growth can occur after precipitation and it is not only related to the calcium level, but it is also temperature dependent. In order to understand the formation mechanism of CA6 precipitates in calcium doped alumina samples, several studies have been carried out using either bulk materials or thin films The crystallization of CA2 and CA6 powders has been studied. Chemical processing techniques were used to synthesize the powders. It was observed that CA2 powders crystallized directly, however CA6 powders crystallized through gamma-Al 2O3 solid solution. The results of energy-loss near-edge spectrometry confirmed that gamma-Al2O3 can dissolve calcium. Calcium aluminate/alumina reaction couples have also been investigated. All reaction couples were heat treated following deposition. It was found that gamma-Al2O3 was formed at the interface as a result of the interfacial reaction between the film and the substrate. gamma-Al 2O3 at the interface was stable at much higher temperatures compared to the bulk gamma-Al2O3 formed prior to the CA6 crystallization. In order to

  12. Calcium addition in straw gasification

    DEFF Research Database (Denmark)

    Risnes, H.; Fjellerup, Jan Søren; Henriksen, Ulrik Birk

    2003-01-01

    The present work focuses on the influence of calcium addition in gasification. The inorganic¿organic element interaction as well as the detailed inorganic¿inorganic elements interaction has been studied. The effect of calcium addition as calcium sugar/molasses solutions to straw significantly...

  13. Zeolite-dye micro lasers

    CERN Document Server

    Vietze, U; Laeri, F; Ihlein, G; Schüth, F; Limburg, B; Abraham, M

    1998-01-01

    We present a new class of micro lasers based on nanoporous molecular sieve host-guest systems. Organic dye guest molecules of 1-Ethyl-4-(4-(p-Dimethylaminophenyl)-1,3-butadienyl)-pyridinium Perchlorat were inserted into the 0.73-nm-wide channel pores of a zeolite AlPO$_4$-5 host. The zeolitic micro crystal compounds where hydrothermally synthesized according to a particular host-guest chemical process. The dye molecules are found not only to be aligned along the host channel axis, but to be oriented as well. Single mode laser emission at 687 nm was obtained from a whispering gallery mode oscillating in a 8-$\\mu$m-diameter monolithic micro resonator, in which the field is confined by total internal reflection at the natural hexagonal boundaries inside the zeolitic microcrystals.

  14. Batchwise dyeing of bamboo cellulose fabric with reactive dye using ultrasonic energy.

    Science.gov (United States)

    Larik, Safdar Ali; Khatri, Awais; Ali, Shamshad; Kim, Seong Hun

    2015-05-01

    Bamboo is a regenerated cellulose fiber usually dyed with reactive dyes. This paper presents results of the batchwise dyeing of bamboo fabric with reactive dyes by ultrasonic (US) and conventional (CN) dyeing methods. The study was focused at comparing the two methods for dyeing results, chemicals, temperature and time, and effluent quality. Two widely used dyes, CI Reactive Black 5 (bis-sulphatoethylsulphone) and CI Reactive Red 147 (difluorochloropyrimidine) were used in the study. The US dyeing method produced around 5-6% higher color yield (K/S) in comparison to the CN dyeing method. A significant savings in terms of fixation temperature (10°C) and time (15 min), and amounts of salt (10 g/L) and alkali (0.5-1% on mass of fiber) was realized. Moreover, the dyeing effluent showed considerable reductions in the total dissolved solids content (minimum around 29%) and in the chemical oxygen demand (minimum around 13%) for the US dyebath in comparison to the CN dyebath. The analysis of colorfastness tests demonstrated similar results by US and CN dyeing methods. A microscopic examination on the field emission scanning electron microscope revealed that the US energy did not alter the surface morphology of the bamboo fibers. It was concluded that the US dyeing of bamboo fabric produces better dyeing results and is a more economical and environmentally sustainable method as compared to CN dyeing method.

  15. The APP670/671 mutation alters calcium signaling and response to hyperosmotic stress in rat primary hippocampal neurons

    DEFF Research Database (Denmark)

    Kloskowska, Ewa; Bruton, Joseph D; Winblad, Bengt;

    2008-01-01

    on the effect of the APP670/671 mutation on spontaneous calcium oscillations in embryonic hippocampal neurons derived from the tg6590 transgenic rat. Intracellular free calcium levels were imaged by confocal microscopy using the fluorescent dye fluo-3AM. Hyperosmotic shrinkage, which can occur in a variety......Altered calcium homeostasis is implicated in the pathogenesis of Alzheimer's disease and much effort has been put into understanding the association between the autosomal dominant gene mutations causative of this devastating disease and perturbed calcium signaling. We have focused our attention...... of pathophysiological conditions, has been shown to induce multiple cellular responses, including activation of volume-regulatory ion transport, cytoskeletal reorganization, and cell death. When exposed to hyperosmotic stress (addition of 50mM sucrose) the frequency of calcium oscillations was suppressed to an equal...

  16. Bioceramics of calcium orthophosphates.

    Science.gov (United States)

    Dorozhkin, Sergey V

    2010-03-01

    A strong interest in use of ceramics for biomedical applications appeared in the late 1960's. Used initially as alternatives to metals in order to increase a biocompatibility of implants, bioceramics have become a diverse class of biomaterials, presently including three basic types: relatively bioinert ceramics, bioactive (or surface reactive) and bioresorbable ones. Furthermore, any type of bioceramics could be porous to provide tissue ingrowth. This review is devoted to bioceramics prepared from calcium orthophosphates, which belong to the categories of bioresorbable and bioactive compounds. During the past 30-40 years, there have been a number of major advances in this field. Namely, after the initial work on development of bioceramics that was tolerated in the physiological environment, emphasis was shifted towards the use of bioceramics that interacted with bones by forming a direct chemical bond. By the structural and compositional control, it became possible to choose whether the bioceramics of calcium orthophosphates was biologically stable once incorporated within the skeletal structure or whether it was resorbed over time. At the turn of the millennium, a new concept of calcium orthophosphate bioceramics, which is able to regenerate bone tissues, has been developed. Current biomedical applications of calcium orthophosphate bioceramics include replacements for hips, knees, teeth, tendons and ligaments, as well as repair for periodontal disease, maxillofacial reconstruction, augmentation and stabilization of the jawbone, spinal fusion and bone fillers after tumor surgery. Potential future applications of calcium orthophosphate bioceramics will include drug-delivery systems, as well as they will become effective carriers of growth factors, bioactive peptides and/or various types of cells for tissue engineering purposes.

  17. Comparative study of calcium alginate, activated carbon, and their composite beads on methylene blue adsorption.

    Science.gov (United States)

    Hassan, A F; Abdel-Mohsen, A M; Fouda, Moustafa M G

    2014-02-15

    Three adsorbents, calcium alginate beads (AB), sodium hydroxide activated carbon based coconut shells (C), and calcium alginate/activated carbon composite beads (ACB) were prepared. Their textural properties were characterized by N2-adsorption at -196°C and scanning electron microscopy. The porosity, surface area and total pore volume of C>ACB>AB, but AB adsorbent was more acidic function groups more than the other adsorbents. Adsorption experiments were conducted to examine the effects of adsorbent dosage, pH, time, temperature and initial concentration of methylene blue. Methylene blue adsorption on C, AB and ACB was observed at pH>6 to avoid the competition of H(+). The amount of dye adsorbed increases as the adsorbent dosage increase. Adsorption of dye follows pseudo-second order mechanism. Thermodynamic studies show spontaneous and endothermic nature of the overall adsorption process.

  18. Adsorptive Properties of Dyes to Cellulosic Sheet and Discoloration of Dye Solution by UV-ray Irradiation

    Institute of Scientific and Technical Information of China (English)

    Zhou Yu; Iida Ikuho; Minato Kazuya; Kurosu Hiroshi

    2005-01-01

    The adsorptive properties and selectivity of dyes and water molecules to cellulosic sheet, dependence of adsorptive properties of dyes on the concentration of dye solution, and discoloration of the dye solution due to the UV-ray irradiation were determined for 18 kinds of commercial dyes. The results are as follows: 1) the adsorptive properties of dyes to cellulose sheet differed greatly, but did not depend on the dye types such as acidic, basic and so on; 2) adsorptive properties of dyes to cellulosic sheet depended on the concentration of dye solution and were classified into 4 types: concentration-independent, increasing or decreasing with dye concentration, and having a maximum. This classification was irrelevant to the dye types; 3) the irradiation of UV-ray did not cause significant discoloration of dye solution itself, which suggested that wood components as well as dye molecules influence the discoloration of wood.

  19. Dye Photodestruction in a Solid-State Dye Laser with a Polymeric Gain Medium

    Science.gov (United States)

    Popov, Sergei

    1998-09-01

    The process of dye photodestruction in a solid-state dye laser is studied, and implemented is a polymeric gain medium doped with a strongly concentrated dye. The behavior of the conversion efficiency in the polymeric gain medium pumped with different laser-pulse repetition rates and the process of dye photobleaching are analyzed. The contribution of the heating of the host material into the dye molecules deactivation is discussed. The negative effect of high dye concentration on the dye stability under a high pump repetition rate is reported and analyzed for the first time to my knowledge. A comparison of the present results with recently published data demonstrates the major role of photodestruction, rather than direct thermodestruction, in the dye stability of the solid-state gain medium. The role of additives with low molecular weights in the polymeric matrix, for increasing the stability of the gain material, is discussed.

  20. Laser dye stability. Pt. 4. Photodegradation relationships for bicyclic dyes in alcohol solutions

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, A.N. (Naval Weapons Center, China Lake, Calif. (USA). Research Dept.)

    1978-05-01

    Changes in the absorption of a dye laser solution are examined after excitation with a xenon flashlamp. It is found that the rate of bleaching as a function of the total input energy of coumarin or quinolone dyes in ethanol increases in direct proportion to the dye concentration. This relationship suggests that the dye reacts with a photoproduct of the solvent rather than being directly decomposed by the xenon flash. We have measured the conversion of the dye to form products, P, absorbing at the lasing wavelength. Results correspond to the dye reacting with a precursor of P to form either insoluble products or ones not absorbing at the lasing wavelength. Thus larger total amounts of bleached dye do not proportionately increase P, and hence do not proportionately inhibit lasing. Furthermore, we find that P increases with the total input energy fairly independent of the rate of bleaching for a given bicyclic dye in an alcohol solution.

  1. Increased light harvesting in dye-sensitized solar cells with energy relay dyes

    KAUST Repository

    Hardin, Brian E.

    2009-06-21

    Conventional dye-sensitized solar cells have excellent charge collection efficiencies, high open-circuit voltages and good fill factors. However, dye-sensitized solar cells do not completely absorb all of the photons from the visible and near-infrared domain and consequently have lower short-circuit photocurrent densities than inorganic photovoltaic devices. Here, we present a new design where high-energy photons are absorbed by highly photoluminescent chromophores unattached to the titania and undergo Förster resonant energy transfer to the sensitizing dye. This novel architecture allows for broader spectral absorption, an increase in dye loading, and relaxes the design requirements for the sensitizing dye. We demonstrate a 26% increase in power conversion efficiency when using an energy relay dye (PTCDI) with an organic sensitizing dye (TT1). We estimate the average excitation transfer efficiency in this system to be at least 47%. This system offers a viable pathway to develop more efficient dye-sensitized solar cells.

  2. Biological wastewater treatment of azo dyes

    Energy Technology Data Exchange (ETDEWEB)

    Shaul, G.M.; Dempsey, C.R.; Dostal, K.A. (Environmental Protection Agency, Cincinnati, OH (USA))

    1988-09-01

    EPA Water Engineering Research Laboratory, Office of Research and Development, undertook a study to determine the fate of specific water soluble azo dye compounds in the activated sludge process (ASP). The study was approached by dosing the feed to the pilot ASP systems with various water soluble azo dyes and by monitoring each dye compound through the system, analyzing both liquid and sludge samples. The fate of the parent dye compound was assessed via mass balance calculations. These data could determine if the compound was removed by adsorption, apparent biodegradation, or not removed at all. The paper presents results for 18 dye compounds tested from June 1985 through August 1987. The study was conducted at EPAs Test and Evaluation Facility in Cincinnati, Ohio. The objective of this study was to determine the partitioning of water soluble azo dyes in the ASP.

  3. Environmentally Friendly Techniques for Wool Dyeing Process

    Directory of Open Access Journals (Sweden)

    Antighin Simona

    2015-11-01

    Full Text Available The aim of this research was to evaluate the influence of dyeing process on the quality of surface waters contaminated with heavy metals and organic compounds, resulted after the wool dyeing process. In order to mark out this aspects an environment friendly method was proposed which involves dyeing wool fiber with new complex combinations derived from a new acid dyes which were complexed, using copper, iron, nickel and zinc salts at 2:1 combination ratio. In order to point out the environmental point of view of wastewaters an experimental protocol was tested by dyeing wool fiber at different pH. Evaluation of complexed combinations impact on the environment involve the following indicators: consumption degree of dyeing solution from the process bath, treatment degree related to the organic content expressed by COD indicator and treatment degree related to the heavy metal concentration respectively.

  4. 1983 Annual Report on Laser Dyes.

    Science.gov (United States)

    1984-04-01

    absorption at the lasing wavelength due to the accumula- tion of reaction products from the photodegradation of a laser dye is analyzed thioretically...Laser Dyes O by A. N. Fletcher Research DopetMrnt APRIL 1984 NAVAL WEAPONS CENTER CHINA LAKE, CALIFORNIA 93555 Appoved for ftc qesege dt"" ba n ftsd...work presented in seven open literature publications on laser dyes . This work originated within the Chemistry Division and was performed and/or

  5. Hair dye poisoning and the developing world

    Directory of Open Access Journals (Sweden)

    Sampathkumar Krishnaswamy

    2009-01-01

    Full Text Available Hair dye poisoning has been emerging as one of the important causes of intentional self harm in the developing world. Hair dyes contain paraphenylene-diamine and a host of other chemicals that can cause rhabdomyolysis, laryngeal edema, severe metabolic acidosis and acute renal failure. Intervention at the right time has been shown to improve the outcome. In this article, we review the various manifestations, clinical features and treatment modalities for hair dye poisoning.

  6. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye

    Science.gov (United States)

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it.

  7. Optimizing the Dyeing Process of Alkali-Treated Polyester Fabric with Dolu Natural Dye

    OpenAIRE

    M. F. Shahin; Ahmed, R. M.

    2014-01-01

    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 PE...

  8. Calcium signaling in taste cells.

    Science.gov (United States)

    Medler, Kathryn F

    2015-09-01

    The sense of taste is a common ability shared by all organisms and is used to detect nutrients as well as potentially harmful compounds. Thus taste is critical to survival. Despite its importance, surprisingly little is known about the mechanisms generating and regulating responses to taste stimuli. All taste responses depend on calcium signals to generate appropriate responses which are relayed to the brain. Some taste cells have conventional synapses and rely on calcium influx through voltage-gated calcium channels. Other taste cells lack these synapses and depend on calcium release to formulate an output signal through a hemichannel. Beyond establishing these characteristics, few studies have focused on understanding how these calcium signals are formed. We identified multiple calcium clearance mechanisms that regulate calcium levels in taste cells as well as a calcium influx that contributes to maintaining appropriate calcium homeostasis in these cells. Multiple factors regulate the evoked taste signals with varying roles in different cell populations. Clearly, calcium signaling is a dynamic process in taste cells and is more complex than has previously been appreciated. This article is part of a Special Issue entitled: 13th European Symposium on Calcium.

  9. Tunable Optofluidic Third Order DFB Dye Laser

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2007-01-01

    We present a low-threshold polymer-based nanofluidic dye laser. By employing a third order DFB laser resonator, we demonstrate a threshold fluence of ~7 muJ/mm2 and a tunability of 45 nm using a single laser dye......We present a low-threshold polymer-based nanofluidic dye laser. By employing a third order DFB laser resonator, we demonstrate a threshold fluence of ~7 muJ/mm2 and a tunability of 45 nm using a single laser dye...

  10. The microbial degradation of azo dyes: minireview.

    Science.gov (United States)

    Chengalroyen, M D; Dabbs, E R

    2013-03-01

    The removal of dyes in wastewater treatment plants still involves physical or chemical processes. Yet numerous studies currently exist on degradation based on the use of microbes-which is a well-studied field. However progress in the use of biological methods to deal with this environmentally noxious waste is currently lacking. This review focuses on the largest dye class, that is azo dyes and their biodegradation. We summarize the bacteria identified thus far which have been implicated in dye decolorization and discuss the enzymes involved and mechanisms by which these colorants are broken down.

  11. Micro-Cavity Fluidic Dye Laser

    DEFF Research Database (Denmark)

    Helbo, Bjarne; Kristensen, Anders; Menon, Aric Kumaran

    2003-01-01

    We have successfully designed, fabricated and characterized a micro-cavity fluidic dye laser with metallic mirrors, which can be integrated with polymer based lab-on-a-chip microsystems without further processing steps. A simple rate-equation model is used to predict the average pumping power...... threshold for lasing as function of cavity-mirror reflectance, laser dye concentration and cavity length. The laser device is characterized using the laser dye Rhodamine 6G dissolved in ethanol. Lasing is observed, and the influence of dye concentration is investigated....

  12. Release Control of Dye from Agar Ball

    OpenAIRE

    板屋, 智之; 山村, 俊貴; 唐澤, 有太朗

    2013-01-01

    Agar is a special product of Nagano prefecture. To utilize agar gel as adsorbing or releasing material of dyes or drugs, spherical agar gel “agar ball” was prepared by dropping aqueous agar solution into salad oil. And releasing behavior of a dye (rhodamine B) from agar ball was studied. The dye is released easily from agar ball, but the release can be controlled by hybiridazation of agar and galatin. In addition, it was found that agar ball could extract the dye from oil phase containing the...

  13. Solubilization of Hydrophobic Dyes in Surfactant Solutions

    Directory of Open Access Journals (Sweden)

    Ali Reza Tehrani-Bagha

    2013-02-01

    Full Text Available In this paper, the use of surfactants for solubilization of hydrophobic organic dyes (mainly solvent and disperse dyes has been reviewed. The effect of parameters such as the chemical structures of the surfactant and the dye, addition of salt and of polyelectrolytes, pH, and temperature on dye solubilization has been discussed. Surfactant self-assemble into micelles in aqueous solution and below the concentration where this occurs—the critical micelle concentration (CMC—there is no solubilization. Above the CMC, the amount of solubilized dye increases linearly with the increase in surfactant concentration. It is demonstrated that different surfactants work best for different dyes. In general, nonionic surfactants have higher solubilization power than anionic and cationic surfactants. It is likely that the reason for the good performance of nonionic surfactants is that they allow dyes to be accommodated not only in the inner, hydrocarbon part of the micelle but also in the headgroup shell. It is demonstrated that the location of a dye in a surfactant micelle can be assessed from the absorption spectrum of the dye-containing micellar solution.

  14. Solvent-free fluidic organic dye lasers.

    Science.gov (United States)

    Choi, Eun Young; Mager, Loic; Cham, Tran Thi; Dorkenoo, Kokou D; Fort, Alain; Wu, Jeong Weon; Barsella, Alberto; Ribierre, Jean-Charles

    2013-05-06

    We report on the demonstration of liquid organic dye lasers based on 9-(2-ethylhexyl)carbazole (EHCz), so-called liquid carbazole, doped with green- and red-emitting laser dyes. Both waveguide and Fabry-Perot type microcavity fluidic organic dye lasers were prepared by capillary action under solvent-free conditions. Cascade Förster-type energy transfer processes from liquid carbazole to laser dyes were employed to achieve color-variable amplified spontaneous emission and lasing. Overall, this study provides the first step towards the development of solvent-free fluidic organic semiconducting lasers and demonstrates a new kind of optoelectronic applications for liquid organic semiconductors.

  15. Accurate simulation of optical properties in dyes.

    Science.gov (United States)

    Jacquemin, Denis; Perpète, Eric A; Ciofini, Ilaria; Adamo, Carlo

    2009-02-17

    Since Antiquity, humans have produced and commercialized dyes. To this day, extraction of natural dyes often requires lengthy and costly procedures. In the 19th century, global markets and new industrial products drove a significant effort to synthesize artificial dyes, characterized by low production costs, huge quantities, and new optical properties (colors). Dyes that encompass classes of molecules absorbing in the UV-visible part of the electromagnetic spectrum now have a wider range of applications, including coloring (textiles, food, paintings), energy production (photovoltaic cells, OLEDs), or pharmaceuticals (diagnostics, drugs). Parallel to the growth in dye applications, researchers have increased their efforts to design and synthesize new dyes to customize absorption and emission properties. In particular, dyes containing one or more metallic centers allow for the construction of fairly sophisticated systems capable of selectively reacting to light of a given wavelength and behaving as molecular devices (photochemical molecular devices, PMDs).Theoretical tools able to predict and interpret the excited-state properties of organic and inorganic dyes allow for an efficient screening of photochemical centers. In this Account, we report recent developments defining a quantitative ab initio protocol (based on time-dependent density functional theory) for modeling dye spectral properties. In particular, we discuss the importance of several parameters, such as the methods used for electronic structure calculations, solvent effects, and statistical treatments. In addition, we illustrate the performance of such simulation tools through case studies. We also comment on current weak points of these methods and ways to improve them.

  16. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes.

    Science.gov (United States)

    Abdou, E M; Hafez, H S; Bakir, E; Abdel-Mottaleb, M S A

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.9×10(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs.

  17. 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.

  18. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes

    Science.gov (United States)

    Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 × 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

  19. Fruit Calcium: Transport and Physiology

    Directory of Open Access Journals (Sweden)

    Bradleigh eHocking

    2016-04-01

    Full Text Available Calcium has well-documented roles in plant signaling, water relations and cell wall interactions. Significant research into how calcium impacts these individual processes in various tissues has been carried out; however, the influence of calcium on fruit ripening has not been thoroughly explored. Here, we review the current state of knowledge on how calcium may impact fruit development, physical traits and disease susceptibility through facilitating developmental and stress response signaling, stabilizing membranes, influencing water relations and modifying cell wall properties through cross-linking of de-esterified pectins. We explore the involvement of calcium in hormone signaling integral to ripening and the physiological mechanisms behind common disorders that have been associated with fruit calcium deficiency (e.g. blossom end rot in tomatoes or bitter pit in apples. This review works towards an improved understanding of how the many roles of calcium interact to influence fruit ripening, and proposes future research directions to fill knowledge gaps. Specifically, we focus mostly on grapes and present a model that integrates existing knowledge around these various functions of calcium in fruit, which provides a basis for understanding the physiological impacts of sub-optimal calcium nutrition in grapes. Calcium accumulation and distribution in fruit is shown to be highly dependent on water delivery and cell wall interactions in the apoplasm. Localized calcium deficiencies observed in particular species or varieties can result from differences in xylem morphology, fruit water relations and pectin composition, and can cause leaky membranes, irregular cell wall softening, impaired hormonal signaling and aberrant fruit development. We propose that the role of apoplasmic calcium-pectin crosslinking, particularly in the xylem, is an understudied area that may have a key influence on fruit water relations. Furthermore, we believe that improved

  20. DISTILLATION OF CALCIUM

    Science.gov (United States)

    Barton, J.

    1954-07-27

    This invention relates to an improvement in the process for the purification of caicium or magnesium containing an alkali metal as impurity, which comprises distiiling a batch of the mixture in two stages, the first stage distillation being carried out in the presence of an inert gas at an absolute pressure substantially greater than the vapor pressure of calcium or maguesium at the temperature of distillation, but less than the vaper pressure at that temperature of the alkali metal impurity so that only the alkali metal is vaporized and condensed on a condensing surface. A second stage distilso that substantially only the calcium or magnesium distills under its own vapor pressure only and condenses in solid form on a lower condensing surface.

  1. Synthesis of calcium superoxide

    Science.gov (United States)

    Rewick, R. T.; Blucher, W. G.; Estacio, P. L.

    1972-01-01

    Efforts to prepare Ca(O2) sub 2 from reactions of calcium compounds with 100% O3 and with O(D-1) atoms generated by photolysis of O3 at 2537 A are described. Samples of Ca(OH) sub 2, CaO, CaO2, Ca metal, and mixtures containing suspected impurities to promote reaction have been treated with excess O3 under static and flow conditions in the presence and absence of UV irradiation. Studies with KO2 suggest that the superoxide anion is stable to radiation at 2537 A but reacts with oxygen atoms generated by the photolysis of O3 to form KO3. Calcium superoxide is expected to behave in an analogous.

  2. 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

  3. 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.

  4. Models of calcium signalling

    CERN Document Server

    Dupont, Geneviève; Kirk, Vivien; Sneyd, James

    2016-01-01

    This book discusses the ways in which mathematical, computational, and modelling methods can be used to help understand the dynamics of intracellular calcium. The concentration of free intracellular calcium is vital for controlling a wide range of cellular processes, and is thus of great physiological importance. However, because of the complex ways in which the calcium concentration varies, it is also of great mathematical interest.This book presents the general modelling theory as well as a large number of specific case examples, to show how mathematical modelling can interact with experimental approaches, in an interdisciplinary and multifaceted approach to the study of an important physiological control mechanism. Geneviève Dupont is FNRS Research Director at the Unit of Theoretical Chronobiology of the Université Libre de Bruxelles;Martin Falcke is head of the Mathematical Cell Physiology group at the Max Delbrück Center for Molecular Medicine, Berlin;Vivien Kirk is an Associate Professor in the Depar...

  5. PREPARATION AND CHARACTERISTICS OF ANIONIC POLYACRYLAMIDES CONTAINING DIRECT DYE WITH A HIGH AFFINITY FOR CELLULOSE

    Directory of Open Access Journals (Sweden)

    Shingo Yokota

    2009-05-01

    Full Text Available Direct dye with a high affinity for cellulose substrate was utilized as a cellulose anchor to promote retention of paper strengthening additives under various conditions associated with the wet end of a paper machine. Direct Red 28 (DR was covalently linked to anionic polyacrylamide (A-PAM via a condensation reaction using water-soluble carbodiimide. The DR-conjugated A-PAM (DR-A-PAM demonstrated good retention efficiency, resulting in strength enhancement of handsheets. Anionic trash showed no interference with the performance of DR-A-PAM in the wet end, while the additive performance was sensitive to calcium ions. Surface plasmon resonance analysis gave useful information on the cellulose-anchoring ability of DR-A-PAM. Dye molecules were irreversibly adsorbed onto the cellulose substrate under aqueous conditions, while A-PAM possessed no significant affinity for cellulose. These results suggest that anionic DR moieties in DR-A-PAM molecules served as a cellulose-anchor, possibly due to multiple CH-π interaction between hydrophobic face of cellulose substrate and π-conjugated system of dye molecules. Such a unique interaction of direct dye and cellulose provides a new insight into the wet end system, and does not depend on conventional electrostatic attraction.

  6. Calcium signalling and calcium channels: evolution and general principles.

    Science.gov (United States)

    Verkhratsky, Alexei; Parpura, Vladimir

    2014-09-15

    Calcium as a divalent cation was selected early in evolution as a signaling molecule to be used by both prokaryotes and eukaryotes. Its low cytosolic concentration likely reflects the initial concentration of this ion in the primordial soup/ocean as unicellular organisms were formed. As the concentration of calcium in the ocean subsequently increased, so did the diversity of homeostatic molecules handling calcium. This includes the plasma membrane channels that allowed the calcium entry, as well as extrusion mechanisms, i.e., exchangers and pumps. Further diversification occurred with the evolution of intracellular organelles, in particular the endoplasmic reticulum and mitochondria, which also contain channels, exchanger(s) and pumps to handle the homeostasis of calcium ions. Calcium signalling system, based around coordinated interactions of the above molecular entities, can be activated by the opening of voltage-gated channels, neurotransmitters, second messengers and/or mechanical stimulation, and as such is all-pervading pathway in physiology and pathophysiology of organisms.

  7. Elemental calcium intake associated with calcium acetate/calcium carbonate in the treatment of hyperphosphatemia

    Science.gov (United States)

    Wilson, Rosamund J; Copley, J Brian

    2017-01-01

    Background Calcium-based and non-calcium-based phosphate binders have similar efficacy in the treatment of hyperphosphatemia; however, calcium-based binders may be associated with hypercalcemia, vascular calcification, and adynamic bone disease. Scope A post hoc analysis was carried out of data from a 16-week, Phase IV study of patients with end-stage renal disease (ESRD) who switched to lanthanum carbonate monotherapy from baseline calcium acetate/calcium carbonate monotherapy. Of the intent-to-treat population (N=2520), 752 patients with recorded dose data for calcium acetate (n=551)/calcium carbonate (n=201) at baseline and lanthanum carbonate at week 16 were studied. Elemental calcium intake, serum phosphate, corrected serum calcium, and serum intact parathyroid hormone levels were analyzed. Findings Of the 551 patients with calcium acetate dose data, 271 (49.2%) had an elemental calcium intake of at least 1.5 g/day at baseline, and 142 (25.8%) had an intake of at least 2.0 g/day. Mean (95% confidence interval [CI]) serum phosphate levels were 6.1 (5.89, 6.21) mg/dL at baseline and 6.2 (6.04, 6.38) mg/dL at 16 weeks; mean (95% CI) corrected serum calcium levels were 9.3 (9.16, 9.44) mg/dL and 9.2 (9.06, 9.34) mg/dL, respectively. Of the 201 patients with calcium carbonate dose data, 117 (58.2%) had an elemental calcium intake of at least 1.5 g/day, and 76 (37.8%) had an intake of at least 2.0 g/day. Mean (95% CI) serum phosphate levels were 5.8 (5.52, 6.06) mg/dL at baseline and 5.8 (5.53, 6.05) mg/dL at week 16; mean (95% CI) corrected serum calcium levels were 9.7 (9.15, 10.25) mg/dL and 9.2 (9.06, 9.34) mg/dL, respectively. Conclusion Calcium acetate/calcium carbonate phosphate binders, taken to control serum phosphate levels, may result in high levels of elemental calcium intake. This may lead to complications related to calcium balance. PMID:28182142

  8. Incorporating Multiple Energy Relay Dyes in Liquid Dye-Sensitized Solar Cells

    KAUST Repository

    Yum, Jun-Ho

    2011-01-05

    Panchromatic response is essential to increase the light-harvesting efficiency in solar conversion systems. Herein we show increased light harvesting from using multiple energy relay dyes inside dye-sensitized solar cells. Additional photoresponse from 400-590 nm matching the optical window of the zinc phthalocyanine sensitizer was observed due to Förster resonance energy transfer (FRET) from the two energy relay dyes to the sensitizing dye. The complementary absorption spectra of the energy relay dyes and high excitation transfer efficiencies result in a 35% increase in photovoltaic performance. © 2011 Wiley-VCH Verlag GmbH& Co. KGaA.

  9. Preparation and Dyeing Performance of a Novel Crosslinking Polymeric Dye Containing Flavone Moiety

    Institute of Scientific and Technical Information of China (English)

    TANG Lijun; TANG Bingtao; ZHANG Shufen

    2011-01-01

    A yellow crosslinking polymeric dye was prepared by grafting the flavone moiety containing azo chromophore onto polyvinylamine backbone.The λ max of this polymeric dye in water is 382 nm.The polymeric dye is fixed to silk and cotton with a crosslinking agent,2-chloro-4,6-di(aminobenzene-4'-β-sulphatoethylsulphone)-1,3,5-s-triazine,which acts as a bridge between the fiber and dye molecules.The fixation of this polymeric dye reaches 99% and the dyed samples exhibit excellent rubbing and washing fastness.

  10. Synthesis of monoazo disperse dyes based on 2-aminoheterocycles and their dyeing performance on nylon fabrics

    Directory of Open Access Journals (Sweden)

    VITHAL SOMA PATEL

    2000-11-01

    Full Text Available Novel monoazo disperse dyes based on various 2-aminoheterocycles were prepared using N-methyl-N-(2-hydroxyethylaniline as the coupling component. All the dyes were applied as disperse dyes on nylon fabric. These dyes have been found to give a wide range of colour shades with very good depth, brightness and levelness on nylon fabric. The visible absorption spectra, elemental analysis and Rf values were investigated. The percentage dye bath exhaustion on fabric was found to be very good. The dyed fabric showed very good to excellent fastness to light, washing, rubbing and perspiration. The sublimation fastness was found to be excellent.

  11. Low Temperature Dyeing of Cashmere Fibers and Products

    Institute of Scientific and Technical Information of China (English)

    SUI Shu-ying; ZHU Ping; CHEN Guo-hua; LI Ru-qin

    2005-01-01

    A special designed multi-functional dyeing auxiliary, SFR503, is adopted in mordant dyeing process for cashmere fibers, sliver and fabric. The results of decreasing dyeing temperature, shortening the dyeing period, reducing the fiber damage and improved quality of the cashmere have been obtained. The percentage of dyeing exhaustion and color fastness of final products were further improved in this regards. A suggested technique, bath ratio, dyeing process curve and dye recipe were raised in the paper. SFR-503s swelling, wetting, leveling, brightening effect for cashmere during dyeing process were discussed.

  12. Dye Sensitized Solar Cell, DSSC

    Directory of Open Access Journals (Sweden)

    Pongsatorn Amornpitoksuk

    2003-07-01

    Full Text Available A dye sensitized solar cell is a new type of solar cell. The operating system of this solar cell type is similar to plant’s photosynthesis process. The sensitizer is available for absorption light and transfer electrons to nanocrystalline metal oxide semiconductor. The ruthenium(II complexes with polypyridyl ligands are usually used as the sensitizers in solar cell. At the present time, the complex of [Ru(2,2',2'’-(COOH3- terpy(NCS3] is the most efficient sensitizer. The total photon to current conversion efficiency was approximately 10% at AM = 1.5.

  13. Characteristics of dye Rhoeo spathacea in dye sensitizer solar cell (DSSC)

    Science.gov (United States)

    Sumardiasih, Sri; Obina, Wilfrida M.; Cari; Supriyanto, Agus; Septiawan, Trio Y.; Khairuddin

    2017-01-01

    Dye-sensitized solar cell (DSSC) is a device that converts solar energy into electrical energy. The magnitude of the efficiency of DSSC is mainly based on the amount of dye absorbed by the surface of TiO2. In this work, used natural dye extracted from leaves Rhoeo spathacea. The dye partially used to immerse of TiO2 as working electrodes, and the rest are directly mixed TiO2 paste to obtain dye titanium dioxide.The paste TiO2 and dye titanium dioxide coated onto the fluorine-doped tin oxide (FTO) glass plate by spin coating method. The absorbance spectra of the dye, dye titanium dioxide and TiO2 were obtained by UV-Vis spectroscopy. The conductivity of the dye, dye titanium dioxide, and TiO2 was measured by two point probe El-Kahfi 100. The DSSC based on dye titanium dioxide that stirring for 5 hours the highest efficiency of 0,0520 % whereas those based on TiO2 immersed for 36 hours showed achieved 0,0501 % obtained from I-V characterization.

  14. Steric and Solvent Effect in Dye-Sensitized Solar Cells Utilizing Phenothiazine-Based Dyes

    Directory of Open Access Journals (Sweden)

    Hany Kafafy

    2014-01-01

    Full Text Available Three phenothiazine-based dyes have been prepared and utilized as dye-sensitized solar cells (DSSCs. The effects of dye-adsorption solvent on the performances of dye-sensitized solar cells based on phenothiazine dyes were investigated in this study. The highest conversion efficiency of 3.78% was obtained using ethanol (EtOH and 2.53% for tetrahydrofuran (THF, respectively, as dye-adsorption solvents. Cell performance using EtOH as a dye-adsorption solvent showed relatively higher performance than that using THF. Electrochemical and photochemical tests of phenothiazine dyes in solution and adsorbed on the TiO2 surface showed less dye loading and coverage on the TiO2 surface during adsorption in the case of THF, which decreased the solar cell performance of the DSSC using THF as adsorption solvent compared with using EtOH as adsorption solvent. Meanwhile, the steric effect of phenothiazine-based (PT1–3 dyes was also investigated. Dye with longer and branched aliphatic chain in the order of PT1, PT2, and PT3 showed an increased resistance of the recombination reaction and electron lifetime, thereby increasing Voc and enhancing the overall cell performance because of the sterically hindered conformation of the phenothiazines.

  15. Characterization of Natural Dye Extracted from Wormwood and Purple Cabbage for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Ho Chang

    2013-01-01

    Full Text Available This study used natural dyes as sensitizers of dye-sensitized solar cells (DSSCs to replace expensive chemical synthetic dyes. We prepared two natural dyes, chlorophyll dye and anthocyanin dye, by extracting them from wormwood and purple cabbage, respectively. Moreover, we mixed the prepared chlorophyll dye and anthocyanin dye at 5 different volume ratios to form cocktail dyes. For preparation of photoelectrode, P25 TiO2 nanoparticles were used to prepare paste, which was coated on fluorine-doped tin oxide (FTO conductive glass by the spin coating method at different spin coating speeds in order to form TiO2 thin films with different thicknesses. The DSSC prepared by the cocktail dye achieves photoelectric conversion efficiency (η of 1.95%, open-circuit voltage (VOC of 0.765 V, and short-circuit current density (JSC of 5.83 mA/cm2. Moreover, the prepared DSSC sensitized solely by chlorophyll extract of wormwood achieved a photoelectric conversion efficiency (η of 0.9%, whereas the DSSC sensitized solely by anthocyanin extract of purple cabbage achieved a photoelectric conversion efficiency of 1.47%, achieving the longest lifetime of electrons amongst these three dyes.

  16. The Influence of Cationization on the Dyeing Performance of Cotton Fabrics with Direct Dyes

    Directory of Open Access Journals (Sweden)

    M. F. Shahin

    2015-08-01

    Full Text Available The effect of cationic modification of cotton fabrics, using cationic agent (Chromatech 9414 on direct dyeing characteristics was studied in this work. Cationization of cotton fabric at different conditions (pH, cationic agent concentration, temperature and time was investigated and the optimum conditions were determined . Nitrogen content of cotton samples pretreated with cationic agent was indicated. The results showed that increasing cationic agent concentration lead to higher nitrogen content on cotton fabric . The cationized cotton fabrics were dyed with two direct dyes (C.I. Direct Yellow 142 - C.I. Direct red 224 and the results were compared to untreated cotton fabrics. The parameters which may affect the dyeing process such as dye concn., addition of salt, time and temperature of dyeing were studied. The dyeing results illustrate that cationization improves the fabric dyeability compared to the uncationized cotton and the magnitude of increase in colour depth depends on the nitrogen content of the cationized cotton fabric .The results also refer to possibility of dyeing cationized cotton fabric with direct dyes without addition of electrolytes to give colour strength higher than that achieved on uncationized cotton using conventional dyeing method .Another important advantage of cationic treatment is in the saving of dye concn., energy ,dyeing time , rinse water and subsequently saving of waste water treatment , and finally minimizes the environmental pollution . The changes in surface morphology of fibres after cationization were identified by various methods such as wettability and scanning with the electron microscope. Different fastness properties were evaluated.

  17. High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells

    KAUST Repository

    Hardin, Brian E.

    2010-08-11

    The energy relay dye, 4-(Dicyanomethylene)-2-methyl-6-(4- dimethylaminostyryl)-4H-pyran (DCM), was used with a near-infrared sensitizing dye, TT1, to increase the overall power conversion efficiency of a dye-sensitized solar cell (DSC) from 3.5% to 4.5%. The unattached DCM dyes exhibit an average excitation transfer efficiency (EÌ?TE) of 96% inside TT1-covered, mesostructured TiO2 films. Further performance increases were limited by the solubility of DCM in an acetonitrile based electrolyte. This demonstration shows that energy relay dyes can be efficiently implemented in optimized dye-sensitized solar cells, but also highlights the need to design highly soluble energy relay dyes with high molar extinction coefficients. © 2010 American Chemical Society.

  18. 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.

  19. Eco-Friendly Dyeing of Cotton with Indigo Dye By Electrochemical Method

    Science.gov (United States)

    Prabu, H. Gurumallesh; Sarala, K.; Babu, S. Ananda; Savitha, K. U.

    2011-07-01

    Eco-friendly dyeing of cotton was performed in two step process; (i) enzymatic pre-treatment of grey cotton fabric and (ii) Electrochemical dyeing of the pre-treated cotton fabric with indigo. The enzymatic pre-treatment was done in three methods; (i) amylase treatment only, (ii) amylase and hydrogen peroxide treatment and (iii) single bath method. The dyeing was carried out with the pre-treated cotton fabric. The reduction of indigo dye by electrochemical method was initiated by applying potential. Then the dyeing was carried out different concentrations of dye, glucose and NaOH. Conventional method of dyeing was also carried out and compared with the electrochemical method. Dyeability was measured by computer colour matching (CCM) GretagMacbeth colour eye 2180UV instrument.

  20. Dyeing of UV irradiated cotton and polyester fabrics with multifunctional reactive and disperse dyes

    Directory of Open Access Journals (Sweden)

    Ijaz Ahmad Bhatti

    2016-03-01

    Full Text Available The dyeing behaviour of UV irradiated cotton and polyester fabrics using multifunctional reactive and disperse dyes has been investigated. The plain, woven, mercerized, bleached, cotton and polyester fabrics were exposed to UV radiation (180 w, 254 nm for 30, 60, 90 and 120 min. Dyeing was performed using irradiated fabric with a dye solution of un-irradiated reactive and disperse/azo dyes. The dyeing parameters such as, temperature, time, pH and salt concentration have been optimized. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton and polyester fabrics in CIE Lab systems using spectra flash SF600. Finally ISO standard methods were employed to observe the effect of UV radiation on fastness properties. It was found that UV radiation has a potential to improve the colour strength values of cotton and polyester fabrics by using reactive and disperse dyes.

  1. Dyeing behaviour of gamma irradiated cotton fabric using Lawson dye extracted from henna leaves (Lawsonia inermis)

    Science.gov (United States)

    Rehman, Fazal-ur; Adeel, Shahid; Qaiser, Summia; Ahmad Bhatti, Ijaz; Shahid, Muhammad; Zuber, Mohammad

    2012-11-01

    Dyeing behavior of gamma irradiated cotton fabric using Lawson dye extracted from henna leaves has been investigated. Cotton and dye powder are irradiated to different absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. The dyeing parameters such as dyeing time, electrolyte (salt) concentration and mordant concentrations using copper and iron as mordants are optimized. Dyeing is performed using un-irradiated and irradiated cotton with dye solutions and their color strength values are evaluated in CIE Lab system using Spectraflash -SF650. Methods suggested by International Standard Organization (ISO) have been employed to investigate the colourfastness properties such as colourfastness to light, washing and rubbing of irradiated dyed fabric. It is found that gamma ray treatment of cotton dyed with extracts of henna leaves has significantly improved the color strength as well as enhanced the rating of fastness properties.

  2. Use of slag for dye removal

    Energy Technology Data Exchange (ETDEWEB)

    Ramakrishna, K.R.; Viraraghavan, T. [Univ. of Regina, Saskatchewan (Canada). Faculty of Engineering

    1998-09-01

    Adsorption techniques employing activated carbon have been found to be reasonably effective in the removal of some of the ionic impurities in water. However, economic considerations may require the use of inexpensive sorbents which are either naturally available or available as waste products from manufacturing processes. Slag is one such waste product obtained during the manufacture of steel, and the present study investigates dye removal characteristics of slag from colored waters. Aqueous solutions prepared from commercial grade acid, basic, and disperse dyes were used in this study, and batch pH, kinetic, and isotherm studies were undertaken on a laboratory scale. The data were evaluated for applicability to the Langmuir, Freundlich, and BET isotherm models, and the removal capacity of slag was compared with that of granular activated carbon. Results indicated approximately 94% removal of the disperse dye by slag, compared with a removal of approximately 49% achieved by activated carbon. Removal of acid dyes (dyes containing anionic groups) was reasonably good (approximately 47 and 74%), though not as good as obtained using activated carbon (approximately 100%). Column studies were conducted with a disperse dye (nonionic, slightly soluble in water), and analysis of data showed a sorption capacity of 1.3 mg of disperse dye per gram of slag. However, effluent dye concentrations were found to be higher than the permissible levels for discharge to receiving waters.

  3. Adsorption of dyes on Sahara desert sand.

    Science.gov (United States)

    Varlikli, Canan; Bekiari, Vlasoula; Kus, Mahmut; Boduroglu, Numan; Oner, Ilker; Lianos, Panagiotis; Lyberatos, Gerasimos; Icli, Siddik

    2009-10-15

    Sahara desert sand (SaDeS) was employed as a mineral sorbent for retaining organic dyes from aqueous solutions. Natural sand has demonstrated a strong affinity for organic dyes but significantly lost its adsorption capacity when it was washed with water. Therefore, characterization of both natural and water washed sand was performed by XRD, BET, SEM and FTIR techniques. It was found that water-soluble kyanite, which is detected in natural sand, is the dominant factor affecting adsorbance of cationic dyes. The sand adsorbs over 75% of cationic dyes but less than 21% for anionic ones. Among the dyes studied, Methylene Blue (MB) demonstrated the strongest affinity for Sahara desert sand (Q(e)=11.98 mg/g, for initial dye solution concentration 3.5 x 10(-5)mol/L). The effects of initial dye concentration, the amount of the adsorbent, the temperature and the pH of the solution on adsorption capacity were tested by using Methylene Blue as model dye. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were applied. It was concluded that adsorption of Methylene Blue on Sahara desert sand followed pseudo-second order kinetics. Gibbs free energy, enthalpy change and entropy change were calculated and found -6411 J/mol, -30360 J/mol and -76.58 J/mol K, respectively. These values indicate that the adsorption is an exothermic process and has a spontaneous nature at low temperatures.

  4. Hair Dye Poisoning in a Paediatric Patient

    Directory of Open Access Journals (Sweden)

    Jolly Chandran

    2012-01-01

    Full Text Available Hair dye ingestion with suicidal intention has increased among rural Indian population and is associated with significant mortality. We report a teenager who presented with cervicofacial edema, respiratory distress, rhabdomyolysis, and myocarditis after ingesting the hair dye Super Vasmol 33. Early and supportive treatment can prevent morbidity and mortality.

  5. Supramolecular assemblies based on glycoconjugated dyes

    NARCIS (Netherlands)

    Schmidt, Bettina

    2016-01-01

    Supramolecular assemblies of glycoconjugated dyes can be tailored with properties that make them attractive for use in biomedical applications. For example, when assemblies of glycoconjugated dyes are displaying carbohydrates on their periphery in a polyvalent manner, these assemblies can be used to

  6. Simultaneous photocatalytic and microbial degradation of dye-containing wastewater by a novel g-C3N4-P25/photosynthetic bacteria composite

    Science.gov (United States)

    Zhang, Xinying; Wu, Yan; Xiao, Gao; Tang, Zhenping; Wang, Meiyin; Liu, Fuchang; Zhu, Xuefeng

    2017-01-01

    Azo dyes are very resistant to light-induced fading and biodegradation. Existing advanced oxidative pre-treatment methods based on the generation of non-selective radicals cannot efficiently remove these dyes from wastewater streams, and post-treatment oxidative dye removal is problematic because it may leave many byproducts with unknown toxicity profiles in the outgoing water, or cause expensive complete mineralization. These problems could potentially be overcome by combining photocatalysis and biodegradation. A novel visible-light-responsive hybrid dye removal agent featuring both photocatalysts (g-C3N4-P25) and photosynthetic bacteria encapsulated in calcium alginate beads was prepared by self-assembly. This system achieved a removal efficiency of 94% for the dye reactive brilliant red X-3b and also reduced the COD of synthetic wastewater samples by 84.7%, successfully decolorized synthetic dye-contaminated wastewater and reduced its COD, demonstrating the advantages of combining photocatalysis and biocatalysis for wastewater purification. The composite apparently degrades X-3b by initially converting the dye into aniline and phenol derivatives whose aryl moieties are then attacked by free radicals to form alkyl derivatives, preventing the accumulation of aromatic hydrocarbons that might suppress microbial activity. These alkyl intermediates are finally degraded by the photosynthetic bacteria. PMID:28273118

  7. Degradation of anthraquinone dyes by ozone

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The decolorization of three kinds of anthraquinone dyes by ozone was investigated and the residues in the degradation solution were analyzed. The results indicate that the decolorizing effects are obvious with the decolorization efficiency of dyes all above 96% in 40 min. The pH value and TOC concentration decline while the conductivity increases with the lapse of reaction time.The complicated dye molecules are decomposed to simple compounds with -SO3H, -Cl in the dye molecules transformed into SO4 2-, Cl-, and nitrogen partially degrades into NO3- according to the bases of different groups. The organic acids are found in the degradation solutions and dyes with larger relative molecular mass are decomposed into substances with larger relative molecular mass.

  8. Dye Sensitizers for Photodynamic Therapy

    Directory of Open Access Journals (Sweden)

    Harold S. Freeman

    2013-03-01

    Full Text Available Photofrin® was first approved in the 1990s as a sensitizer for use in treating cancer via photodynamic therapy (PDT. Since then a wide variety of dye sensitizers have been developed and a few have been approved for PDT treatment of skin and organ cancers and skin diseases such as acne vulgaris. Porphyrinoid derivatives and precursors have been the most successful in producing requisite singlet oxygen, with Photofrin® still remaining the most efficient sensitizer (quantum yield = 0.89 and having broad food and drug administration (FDA approval for treatment of multiple cancer types. Other porphyrinoid compounds that have received approval from US FDA and regulatory authorities in other countries include benzoporphyrin derivative monoacid ring A (BPD-MA, meta-tetra(hydroxyphenylchlorin (m-THPC, N-aspartyl chlorin e6 (NPe6, and precursors to endogenous protoporphyrin IX (PpIX: 1,5-aminolevulinic acid (ALA, methyl aminolevulinate (MAL, hexaminolevulinate (HAL. Although no non-porphyrin sensitizer has been approved for PDT applications, a small number of anthraquinone, phenothiazine, xanthene, cyanine, and curcuminoid sensitizers are under consideration and some are being evaluated in clinical trials. This review focuses on the nature of PDT, dye sensitizers that have been approved for use in PDT, and compounds that have entered or completed clinical trials as PDT sensitizers.

  9. Molecular engineering of simple phenothiazine-based dyes to modulate dye aggregation, charge recombination, and dye regeneration in highly efficient dye-sensitized solar cells.

    Science.gov (United States)

    Hua, Yong; Chang, Shuai; He, Jian; Zhang, Caishun; Zhao, Jianzhang; Chen, Tao; Wong, Wai-Yeung; Wong, Wai-Kwok; Zhu, Xunjin

    2014-05-19

    A series of simple phenothiazine-based dyes, namely, TP, EP, TTP, ETP, and EEP have been developed, in which the thiophene (T), ethylenedioxythiophene (E), their dimers, and mixtures are present to modulate dye aggregation, charge recombination, and dye regeneration for highly efficient dye-sensitized solar cell (DSSC) applications. Devices sensitized by the dyes TP and TTP display high power conversion efficiencies (PCEs) of 8.07 (Jsc = 15.2 mA cm(-2), Voc =0.783 V, fill factor (FF) = 0.679) and 7.87 % (Jsc = 16.1 mA cm(-2), Voc = 0.717 V, FF = 0.681), respectively; these were measured under simulated AM 1.5 sunlight in conjunction with the I(-)/I3(-) redox couple. By replacing the T group with the E unit, EP-based DSSCs had a slightly lower PCE of 7.98 % with a higher short-circuit photocurrent (Jsc) of 16.7 mA cm(-2). The dye ETP, with a mixture of E and T, had an even lower PCE of 5.62 %. Specifically, the cell based on the dye EEP, with a dimer of E, had inferior Jsc and Voc values and corresponded to the lowest PCE of 2.24 %. The results indicate that the photovoltaic performance can be finely modulated through structural engineering of the dyes. The selection of T analogues as donors can not only modulate light absorption and energy levels, but also have an impact on dye aggregation and interfacial charge recombination of electrons at the interface of titania, electrolytes, and/or oxidized dye molecules; this was demonstrated through DFT calculations, electrochemical impedance analysis, and transient photovoltage studies.

  10. Simultaneous imaging of structural plasticity and calcium dynamics in developing dendrites and axons.

    Science.gov (United States)

    Siegel, Friederike; Lohmann, Christian

    2013-11-01

    During nervous system development, the formation of synapses between pre- and postsynaptic neurons is a remarkably specific process. Both structural and functional plasticity are critical for the selection of synaptic partners and for the establishment and maturation of synapses. To unravel the respective contributions of structural and functional mechanisms as well as their interactions during synaptogenesis, it is important to directly observe structural changes and functional signaling simultaneously. Here, we present an imaging approach to simultaneously follow changes in structure and function. Differential labeling of individual cells and the neuronal network with distinct dyes allows the study of structural plasticity and changes in calcium signaling associated with neural activity at the same time and with high resolution. This is achieved by bulk loading of neuronal populations with a calcium-sensitive indicator in combination with electroporation of individual cells with a calcium indicator and an additional noncalcium-sensitive dye with a different excitation spectrum. Recordings of the two differently labeled structures can be acquired simultaneously using confocal microscopy. Thus, structural plasticity and calcium dynamics of the individually labeled neuron and the surrounding network can be related to each other. This combined imaging approach can be applied to virtually all systems of neuronal networks to study structure and function. We provide a comprehensive description of the labeling procedure, the imaging parameters, and the important aspects of analysis for simultaneous recordings of structure and function in individual neurons.

  11. Calcium – how and why?

    Indian Academy of Sciences (India)

    J K Jaiswal

    2001-09-01

    Calcium is among the most commonly used ions, in a multitude of biological functions, so much so that it is impossible to imagine life without calcium. In this article I have attempted to address the question as to how calcium has achieved this status with a brief mention of the history of calcium research in biology. It appears that during the origin and early evolution of life the Ca2+ ion was given a unique opportunity to be used in several biological processes because of its unusual physical and chemical properties.

  12. Calcium Phosphate Biomaterials: An Update

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Current calcium phosphate (CaP) biomaterials for bone repair, substitution, augmentation and regeneration include hydroxyapatite ( HA ) from synthetic or biologic origin, beta-tricalcium phosphate ( β-TCP ) , biphasic calcium phosphate (BCP), and are available as granules, porous blocks, components of composites (CaP/polymer) cements, and as coatings on orthopedic and dental implants. Experimental calcium phosphate biomaterials include CO3- and F-substituted apatites, Mg-and Zn-substituted β-TCP, calcium phosphate glasses. This paper is a brief review of the different types of CaP biomaterials and their properties such as bioactivity, osteoconductivity, osteoinductivity.

  13. Calcium measurement methods

    Directory of Open Access Journals (Sweden)

    CarloAlberto Redi

    2010-09-01

    Full Text Available Rightly stressed by prof. Wolfgang Walz in the Preface to the series Neuromethods series, the “careful application of methods is probably the most important step in the process of scientific inquiry”. Thus, I strongly suggest to all those interested in calcium signaling and especially to the new-comers in the hot topic of neuroscience (which has so much space even in science-society debate for its implications in legal issues and in the judge-decision process to take profit from this so well edited book. I am saying this since prof. Verkhratsky and prof. Petersen......

  14. Extracellular calcium sensing and extracellular calcium signaling

    Science.gov (United States)

    Brown, E. M.; MacLeod, R. J.; O'Malley, B. W. (Principal Investigator)

    2001-01-01

    , localized changes in Ca(o)(2+) within the ECF can originate from several mechanisms, including fluxes of calcium ions into or out of cellular or extracellular stores or across epithelium that absorb or secrete Ca(2+). In any event, the CaR and other receptors/sensors for Ca(o)(2+) and probably for other extracellular ions represent versatile regulators of numerous cellular functions and may serve as important therapeutic targets.

  15. Effect of mitochondrial calcium uniporter blocking on human spermatozoa.

    Science.gov (United States)

    Bravo, A; Treulen, F; Uribe, P; Boguen, R; Felmer, R; Villegas, J V

    2015-08-01

    Calcium (Ca(2+) ) regulates a number of essential processes in spermatozoa. Ca(2+) is taken up by mitochondria via the mitochondrial calcium uniporter (mCU). Oxygen-bridged dinuclear ruthenium amine complex (Ru360) has been used to study mCU because it is a potent and specific inhibitor of this channel. In bovine spermatozoa, it has been demonstrated that mitochondrial calcium uptake inhibition adversely affects the capacitation process. It has been demonstrated in human spermatozoa that mCU blocking, through Ru360, prevents apoptosis; however, the contribution of the mCU to normal human sperm function has not been studied. Therefore, the aim of this study was to evaluate the effect of mCU blocking on human sperm function. Spermatozoa obtained from apparently healthy donors were incubated with 5 and 10 μm Ru360 for 4 h at 37 °C. Viability was assessed using propidium iodide staining; motility was determined by computer-aided sperm analysis, adenosine triphosphate (ATP) levels using a luminescence-based method, mitochondrial membrane potential (ΔΨm) using JC-1 staining and reactive oxygen species (ROS) production using dihydroethidium dye. Our results show that mCU blocking significantly reduced total sperm motility and ATP levels without affecting sperm viability, ΔΨm and ROS production. In conclusion, mCU contributes to the maintenance of sperm motility and ATP levels in human spermatozoa.

  16. Photophysical and electrochemical properties, and molecular structures of organic dyes for dye-sensitized solar cells.

    Science.gov (United States)

    Ooyama, Yousuke; Harima, Yutaka

    2012-12-21

    Dye-sensitized solar cells (DSSCs) based on organic dyes adsorbed on oxide semiconductor electrodes, such as TiO(2), ZnO, or NiO, which have emerged as a new generation of sustainable photovoltaic devices, have attracted much attention from chemists, physicists, and engineers because of enormous scientific interest in not only their construction and operational principles, but also in their high incident-solar-light-to-electricity conversion efficiency and low cost of production. To develop high-performance DSSCs, it is important to create efficient organic dye sensitizers, which should be optimized for the photophysical and electrochemical properties of the dyes themselves, with molecular structures that provide good light-harvesting features, good electron communication between the dye and semiconductor electrode and between the dye and electrolyte, and to control the molecular orientation and arrangement of the dyes on a semiconductor surface. The aim of this Review is not to make a list of a number of organic dye sensitizers developed so far, but to provide a new direction in the epoch-making molecular design of organic dyes for high photovoltaic performance and long-term stability of DSSCs, based on the accumulated knowledge of their photophysical and electrochemical properties, and molecular structures of the organic dye sensitizers developed so far.

  17. Dye sequestration using agricultural wastes as adsorbents

    Directory of Open Access Journals (Sweden)

    Kayode Adesina Adegoke

    2015-12-01

    Full Text Available Color is a visible pollutant and the presence of even minute amounts of coloring substance makes it undesirable due to its appearance. The removal of color from dye-bearing effluents is a major problem due to the difficulty in treating such wastewaters by conventional treatment methods. The most commonly used methods for color removal are biological oxidation and chemical precipitation. However, these processes are effective and economic only in the case where the solute concentrations are relatively high. Most industries use dyes and pigments to color their products. The presence of dyes in effluents is a major concern due to its adverse effect on various forms of life. The discharge of dyes in the environment is a matter of concern for both toxicological and esthetical reasons. It is evident from a literature survey of about 283 recently published papers that low-cost adsorbents have demonstrated outstanding removal capabilities for dye removal and the optimal equilibrium time of various dyes with different charcoal adsorbents from agricultural residues is between 4 and 5 h. Maximum adsorptions of acidic dyes were obtained from the solutions with pH 8–10. The challenges and future prospects are discussed to provide a better framework for a safer and cleaner environment.

  18. Advanced oxidation of acid and reactive dyes

    DEFF Research Database (Denmark)

    Arslan-Alaton, I.; Gursoy, B.H.; Schmidt, Jens Ejbye

    2008-01-01

    M) for 10:hsp sp="0.25" min Fenton treatment at pH 3, resulting in reduced chemical oxygen demand and dissolved organic carbon removal efficiencies; only acetate was detected as a stable dye oxidation end product. During anaerobic digestion, 100, 29% and no inhibition in methane production was observed...... for the untreated blue, red and orange dyes, respectively. The inhibitory effect of the blue reactive dye on methane production was ∼21% after Fenton treatment. Neither untreated nor treated dyes exhibited an inhibitory effect on denitrification. Aerobic glucose degradation was inhibited by 23-29% by untreated dyes......The effect of untreated and Fenton-treated acid dyes (C.I. Acid Red 183 and C.I. Acid Orange 51) and a reactive dye (C.I. Reactive Blue 4) on aerobic, anoxic and anaerobic processes was investigated. The optimum Fe2+:H2O2 molar ratio was selected as 1:5 (4:hsp sp="0.25" mM:20:hsp sp="0.25"m...

  19. Molecularly imprinted polymers for some reactive dyes.

    Science.gov (United States)

    Okutucu, Burcu; Akkaya, Alper; Pazarlioglu, Nurdan Kasikara

    2010-01-01

    Depending upon their structure, azo- and anthraquinonic dyes are the two major classes and together represent 90% of all organic colorants. Adsorption of dye molecules onto a sorbent can be an effective, low-cost method of color removal. Most of the techniques used for removal of dyes are of high production cost, and the regeneration also makes them uneconomical. There is much interest in the development of cheaper and effective newer materials for use as adsorbents. Molecular imprinting is a new kind of materials that can be alternative adsorbents. In this study, molecularly imprinted polymers of three textile dyes (Cibacron Orange P-4R, Cibacron Red P-4B, Cibacron Black PSG) were prepared. Methacrylic acid was used as a monomer for red and orange dyes and acrylamide was used for black dye. Methanol:acetonitrile was used as a porogen. The selective recognition ability of the molecularly imprinted polymers was studied by an equilibrium-adsorption batch method. The adsorption data are for Cibacron Black PSG 65% and nonimprinted polymer (NIP) 25%; Cibacron Red P-4B 72% and NIP 18%; and Cibacron Orange P-4R 45% and NIP 10%, respectively. Dye-imprinted polymers were used as a solid-phase extraction material for selective adsorption from wastewater of textile factory.

  20. Ultrasound energy to accelerate dye uptake and dye-fiber interaction of reactive dye on knitted cotton fabric at low temperatures.

    Science.gov (United States)

    Tissera, Nadeeka D; Wijesena, Ruchira N; de Silva, K M Nalin

    2016-03-01

    Acoustic cavitation formed due to propagation of ultrasound wave inside a dye bath was successfully used to dye cotton fabric with a reactive dye at lower temperatures. The energy input to the system during sonication was 0.7 W/cm(2). This was within the energy range that contributes towards forming cavitation during ultra-sonication. The influence of ultrasound treatment on dye particle size and fiber morphology is discussed. Particle size analysis of the dye bath revealed ultra-sonication energy was capable of de-agglomeration of hydrolyzed dye molecules during dyeing. SEM micrograph and AFM topographical image of the fiber surface revealed fiber morphology remains unchanged after the sonication. The study was extended in understanding the contribution of ultrasound method of dyeing towards achieving good color strength on the fabric, compared to the normal heating method of dyeing. Study showed color strength obtained using ultra sound method of dyeing is higher compared to normal heating dyeing. Ultrasound energy was able to achieve the good color strength on cotton fabric at very low temperature such as 30 °C, which was approximately 230% more than the color strength achieved in normal heating method of dyeing. This indicates that energy input to the system using ultrasound was capable of acting as an effective alternative method of dyeing knitted cotton fabrics with reactive dye.

  1. Vitamin D, Calcium, and Bone Health

    Science.gov (United States)

    ... in Balance › Vitamin D, Calcium, and Bone Health Vitamin D, Calcium, and Bone Health March 2012 Download ... also helps keep your bones strong. Why are vitamin D and calcium important to bone health? Vitamin ...

  2. Calcium, vitamin D, and your bones

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000490.htm Calcium, vitamin D, and your bones To use the sharing ... and maintain strong bones. How Much Calcium and Vitamin D do I Need? Amounts of calcium are ...

  3. Contact allergy to common ingredients in hair dyes

    DEFF Research Database (Denmark)

    Søsted, Heidi; Rustemeyer, Thomas; Gonçalo, Margarida

    2013-01-01

    p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed.......p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed....

  4. Supramolecular hair dyes: a new application of cocrystallization

    DEFF Research Database (Denmark)

    Delori, Amit; Urquhart, Andrew; Oswald, Iain D. H.

    2016-01-01

    The manuscript presents the first report of hair dyes of various colors formed by cocrystallization. Unlike the most popular oxidative hair dye (OHD) products, these dyes are NH3 free and do not require H2O2 as a color developer. The importance of these new hair dyes products is further enhanced...

  5. Bleaching and diffusion dynamics in optofluidic dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Balslev, Søren; Mortensen, Asger

    2007-01-01

    The authors have investigated the bleaching dynamics that occur in optofluidic dye lasers where the liquid laser dye in a microfluidic channel is locally bleached due to optical pumping. They find that for microfluidic devices, the dye bleaching may be compensated through diffusion of dye molecules...... pumping devices. ©2007 American Institute of Physics....

  6. Dyeing Performance of Soybean Fiber Treated with Low Temperature Plasma

    Institute of Scientific and Technical Information of China (English)

    WANG Li-ming; SHEN Yong; DING Ying; ZHANG Hui-fang

    2006-01-01

    The soybean fiber was treated with low temperature plasma and the dyeing performance of the treated soybean fiber was also researched. The results show that the speed of dyeing and the percentages of balance dyeing have a sharp increase after being treated. So the dyeing temperature and the dosage of acid can be reduced without damaging the bulk fiber structure.

  7. Vitamin D and Intestinal Calcium Absorption

    OpenAIRE

    Christakos, Sylvia; Dhawan, Puneet; Porta, Angela; Mady, Leila J.; Seth, Tanya

    2011-01-01

    The principal function of vitamin D in calcium homeostasis is to increase calcium absorption from the intestine. Calcium is absorbed by both an active transcellular pathway, which is energy dependent, and by a passive paracellular pathway through tight junctions. 1,25Dihydroxyvitamin D3 (1,25(OH)2D3) the hormonally active form of vitamin D, through its genomic actions, is the major stimulator of active intestinal calcium absorption which involves calcium influx, translocation of calcium throu...

  8. Mammary-Specific Ablation of the Calcium-Sensing Receptor During Lactation Alters Maternal Calcium Metabolism, Milk Calcium Transport, and Neonatal Calcium Accrual

    OpenAIRE

    Mamillapalli, Ramanaiah; VanHouten, Joshua; Dann, Pamela; Bikle, Daniel; Chang, Wenhan; Brown, Edward; Wysolmerski, John

    2013-01-01

    To meet the demands for milk calcium, the lactating mother adjusts systemic calcium and bone metabolism by increasing dietary calcium intake, increasing bone resorption, and reducing renal calcium excretion. As part of this adaptation, the lactating mammary gland secretes PTHrP into the maternal circulation to increase bone turnover and mobilize skeletal calcium stores. Previous data have suggested that, during lactation, the breast relies on the calcium-sensing receptor (CaSR) to coordinate ...

  9. Dye ingredients and energy conversion efficiency at natural dye sensitized solar cells

    Science.gov (United States)

    Özbay Karakuş, Mücella; Koca, İrfan; Er, Orhan; Çetin, Hidayet

    2017-04-01

    In this work, natural dyes extracted from the same genus but different species flowers were used as sensitizer in Dye Sensitized Solar Cell (DSSC). To clearly show dye ingredients effect on electrical characteristics, the same genus flowers were selected. The dye ingredients were analyzed by Gas Chromatography Mass Spectrometer (GC-MS). The dyes were modified by a procedure that includes refluxing in acetone. All results indicate a relationship between gallic acid quantity in dyes and solar cell efficiency. To gain further insight, the solar cell parameters were obtained by using the single-diode and double-diode models and they were compared to each other. It was observed that the applied process causes a decrease in series resistance. How the modification process and gallic acid affect energy conversion efficiency were argued in detail in the frame of results that were obtained from solar cell models.

  10. Decolourisation of Red 5 MB dye by microbes isolated from textile dye effluent.

    Science.gov (United States)

    Subashini, P; Hiranmaiyadav, R; Premalatha, M S

    2010-07-01

    One of the major environmental problems is the presence of dye materials in textile wastewater, which need to be removed before releasing into the environment. Some dyes are toxic and carcinogenic in nature. The discharge of the textile effluent into rivers and lakes leads to higher BOD causing threat to aquatic life. Development of efficient dye degradation requires suitable strain and its use under favorable condition to realize the degradation potential. In this study, three microorganisms were isolated from the Red 5 MB dye containing textile wastewater. They were identified and tested for the dye decolourisation provided with different sugars as carbon source. The percentage of dye decolorized by Bacillus subtilis, Aspergillus flavus and Aspergillus fumigatus were found to be about 40%, 75% and 53.8% respectively.

  11. Molecular design of organic dyes based on vinylene hexylthiophene bridge for dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Three donor-(π-spacer)-acceptor(D-π-A) organic dyes,containing different groups(triphenylamine,di(p-tolyl)phenylamine,and 9-octylcarbazole moieties) as electron donors,were designed and synthesized.Nanocrystalline TiO2 dye-sensitized solar cells were fabricated by using these dyes.It was found that the variation of electron donors in the D-π-A dyes played an important role in modifying and tuning photophysical properties of organic dyes.Under standard global AM 1.5 solar condition,the DSSC based on the dye D2 showed the best photovoltaic performance:a short-circuit photocurrent density(Jsc) of 13.93 mA/cm2,an open-circuit photovoltage(Voc) of 0.71 V,and a fill factor(FF) of 0.679,corresponding to solar-to-electric power conversion efficiency(η) of 6.72%.

  12. Molecular design of organic dyes based on vinylene hexylthiophene bridge for dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    LIU DaXi; ZHAO Bin; SHEN Ping; HUANG Hui; LIU LiMing; TAN SongTing

    2009-01-01

    Three donor-(TT-spacer)-acceptor (D-tt-A) organic dyes,containing different groups (triphenylamine,di(p-tolyl)phenylamine,and 9-octylcarbazole moieties) as electron donors,were designed and synthesized. Nanocrystalline TiO2 dye-sensitized solar cells were fabricated by using these dyes. It was found that the variation of electron donors in the D-tt-A dyes played an important role in modifying and tuning photophysical properties of organic dyes. Under standard global AM 1.5 solar condition,the DSSC based on the dye D2 showed the best photovoltaic performance: a short-circuit photocurrent density (Jsc) of 13.93 mA/cm2,an open-circuit photovoltage (Voc) of 0.71 V,and a fill factor (FF) of 0.679,corresponding to solar-to-electric power conversion efficiency (77) of 6.72%.

  13. Auranofin, an Anti-Rheumatic Gold Compound, Modulates Apoptosis by Elevating the Intracellular Calcium Concentration ([Ca2+]i in MCF-7 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Elizabeth Varghese

    2014-11-01

    Full Text Available Auranofin, a transition metal complex is used for the treatment of rheumatoid arthritis but is also an effective anti-cancer drug. We investigate the effects of Auranofin in inducing cell death by apoptosis and whether these changes are correlated to changes of intracellular calcium concentration ([Ca2+]i in breast cancer cells (MCF-7. Cytotoxicity of Auranofin was evaluated using MTS assay and the Trypan blue dye exclusion method. With fluorescent dyes SR-FLICA and 7-AAD apoptotic death and necrotic death were differentiated by Flow cytometry. A concentration dependent decrease in the viability occurred and cells were shifted to the apoptotic phase. Intracellular calcium ([Ca2+]i was recorded using florescence microscopy and a calcium sensitive dye (Fluo-4 AM with a strong negative correlation (r = −0.713 to viability. Pharmacological modulators 2-APB (50 μM, Nimodipine (10 μM, Caffeine (10 mM, SKF 96365(20 μM were used to modify calcium entry and release. Auranofin induced a sustained increase of [Ca2+]i in a concentration and time dependent manner. The use of different blockers of calcium channels did not reveal the source for the rise of [Ca2+]i. Overall, elevation of [Ca2+]i by Auranofin might be crucial for triggering Ca2+-dependent apoptotic pathways. Therefore, in anti-cancer therapy, modulating [Ca2+]i should be considered as a crucial factor for the induction of cell death in cancer cells.

  14. 21 CFR 184.1191 - Calcium carbonate.

    Science.gov (United States)

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of... soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the...

  15. Data mining with molecular design rules identifies new class of dyes for dye-sensitised solar cells

    NARCIS (Netherlands)

    Cole, Jacqueline M.; Low, Kian Sing; Ozoe, Hiroaki; Stathi, Panagiota; Kitamura, Chitoshi; Kurata, Hiroyuki; Rudolf, Petra; Kawase, Takeshi

    2014-01-01

    A major deficit in suitable dyes is stifling progress in the dye-sensitised solar cell (DSC) industry. Materials discovery strategies have afforded numerous new dyes; yet, corresponding solution-based DSC device performance has little improved upon 11% efficiency, achieved using the N719 dye over tw

  16. The Removal of Composite Reactive Dye from Dyeing Unit Effluent Using Sewage Sludge Derived Activated Carbon

    OpenAIRE

    REDDY, Sajjala SREEDHAR

    2006-01-01

    Activated carbon was prepared from dried municipal sewage sludge and batch mode adsorption experiments were conducted to study its potential to remove composite reactive dye from dyeing unit effluent. Adsorption parameters for the Langmuir and Freundlich isotherms were determined and the effects of effluent pH, adsorbent dosage, contact time and initial dye concentration were studied. The toxicity characteristic leaching protocol (TCLP) was used to assess the acceptability of sewage ...

  17. Natural Dye Extracted from Vitex negundo as a Potential Alternative to Synthetic Dyes for Dyeing of Silk

    Science.gov (United States)

    Narayana Swamy, Venkataramanappa; Gowda, Kurikempanadoddi Ninge; Sudhakar, Rajagopal

    2016-04-01

    Since the last decade, the application of natural dyes on textile material has been gaining popularity all over the world, possibly because of the increasing awareness of issues concerning the environment, ecology and pollution control. The present paper investigates extraction of natural dye from leaves of the plant Vitex negundo, which is an abundant, cheap, and readily available agricultural by-product. Water extracts from V. negundo was used to dye silk fabrics. Optimum extraction conditions included pH 9, duration 120 min, and temperature 90 °C. Optimum dyeing conditions included dyeing pH 5 and duration of 60 min. Potash alum, tannic and tartaric acid were used as mordants, all of which are benign to human health and the environment. Color strength and color coordinates in terms of L*, a*, b*, C, and h were examined. A range of shades were obtained when fabrics were dyed with different mordants and mordanting techniques. The extracted dye was tested for some of the eco-parameters using atomic absorption spectrophotometry and GC/MS. The test results were compared with set standards to determine the eco-friendliness of natural dye. Their concentrations were found to be lower than the stipulated limits. Dyed samples were tested for antimicrobial activity against gram-positive and gram-negative bacteria. The dyed silk fabrics showed acceptable fastness properties and were also found to possess antibacterial activity. It can be concluded that the abundantly available agricultural by-product V. negundo has great potential to be effectively utilized as a natural dye for silk.

  18. Simulation of Na channel inactivation by thiazine dyes

    OpenAIRE

    1982-01-01

    Some dyes of the methylene blue family serve as artificial inactivators of the sodium channels when present inside squid axons at a concentration of approximately 0.1 mM. The dyes restore a semblance of inactivation after normal inactivation has been destroyed by pronase. In fibers that inactivate normally, the dyes hasten the decay of sodium current. Many dye-blocked channels conduct transiently on exit of the dye molecule after repolarization to the holding potential. In contrast, normally ...

  19. Evolution of the Calcium Paradigm: The Relation between Vitamin D, Serum Calcium and Calcium Absorption

    Directory of Open Access Journals (Sweden)

    Borje E. Christopher Nordin

    2010-09-01

    Full Text Available Osteoporosis is the index disease for calcium deficiency, just as rickets/osteomalacia is the index disease for vitamin D deficiency, but there is considerable overlap between them. The common explanation for this overlap is that hypovitaminosis D causes malabsorption of calcium which then causes secondary hyperparathyroidism and is effectively the same thing as calcium deficiency. This paradigm is incorrect. Hypovitaminosis D causes secondary hyperparathyroidism at serum calcidiol levels lower than 60 nmol/L long before it causes malabsorption of calcium because serum calcitriol (which controls calcium absorption is maintained until serum calcidiol falls below 20 nmol/L. This secondary hyperparathyroidism, probably due to loss of a “calcaemic” action of vitamin D on bone first described in 1957, destroys bone and explains why vitamin D insufficiency is a risk factor for osteoporosis. Vitamin D thus plays a central role in the maintenance of the serum (ionised calcium, which is more important to the organism than the preservation of the skeleton. Bone is sacrificed when absorbed dietary calcium does not match excretion through the skin, kidneys and bowel which is why calcium deficiency causes osteoporosis in experimental animals and, by implication, in humans.

  20. Effect of Solvent, Dye-Loading Time, and Dye Choice on the Performance of Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Fahd M. Rajab

    2016-01-01

    Full Text Available Anatase titania films with a thickness of up to 20 μm and deposited over a fluorine-doped tin-oxide substrate are impregnated with ruthenium dyes N-719 and N-749 using Dip and supercritical-fluid methods for the purpose of fabricating dye-sensitized solar cell devices. The dyes are dissolved in different solvent mixtures, including supercritical carbon dioxide, as well as combinations of more traditional solvents including mixtures of acetonitrile, and t-butanol. Analytical studies included thin-film analyzing and scanning electron microscopy to measure titania film thickness and porosity, UV-Vis spectroscopy to quantify dye concentration, and current-voltage device characterizations to assess energy conversion efficiency, as well as open-circuit voltage decay measurements and quantum efficiency to examine electron collection efficiency. A significant result is that using the dye N-749 in a solvent that includes supercritical carbon dioxide leads to energy conversion efficiencies that are higher for devices with a thick 20 μm semiconductor film than for the case of devices with thinner films, including the 10 μm film thickness that is traditionally considered an upper threshold. The supercritical-fluid method for the N-719 dye also enabled shorter impregnation duration than more conventional classical Dip Methods.

  1. USE OF A NATURAL DYE FROM SERRATIA MARCESCENS SUBSPECIES MARCESCENS IN DYEING OF TEXTILE FABRICS

    Directory of Open Access Journals (Sweden)

    Ravindra Adivarekar

    2013-06-01

    Full Text Available A strain of Serratia marcescens subspecies marcescens capable of producing a novel rose red pigment with a mass of 112 Da has been isolated from Mahim Mangroove soil. Studies regarding the growth conditions of bacteria, partial characterization of the produced pigment and use of this rose red pigment to dye natural fabrics has been studied and described. Dyeing of wool, cotton and silk fabrics with this rose red microbial pigment as natural dye indicated that the colour strength values and the dye uptake were high with satisfactory fastness properties of the dyed fabric.

  2. Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability

    Directory of Open Access Journals (Sweden)

    Babita Rani

    2014-09-01

    Full Text Available Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85% followed by Nigrosin (77.47%, Malachite green (72.77% and dye mixture (33.08% under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15% followed by Basic fuchsin (89.8%, Malachite green (83.25% and mixture (78.4%. The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination.

  3. Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability.

    Science.gov (United States)

    Rani, Babita; Kumar, Vivek; Singh, Jagvijay; Bisht, Sandeep; Teotia, Priyanku; Sharma, Shivesh; Kela, Ritu

    2014-01-01

    Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85%) followed by Nigrosin (77.47%), Malachite green (72.77%) and dye mixture (33.08%) under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15%) followed by Basic fuchsin (89.8%), Malachite green (83.25%) and mixture (78.4%). The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination.

  4. Dyeing of Organic Cotton Fabric using Conventional and Ultrasonic Exhaust Dyeing Method

    Directory of Open Access Journals (Sweden)

    Uzma Syed

    2013-04-01

    Full Text Available In this research dyeing behavior of organic cotton woven fabric using ultrasonic technique and conventional dyeing method has been compared. The fabric samples were dyed with reactive dyes Drimarene Red Cl-5B and Drimarene Blue Cl-BR (0.5% owf using exhaust dyeing method. The samples were ultrasonically dyed at varied temperature (60, 50 and 40oC for 60, 50, 40 and 30 minutes and for conventional method at varied temperature but at recommended time, 60 minutes. For optimizing the dyeing behavior, the samples were causticized by pad-batch method and then dyed with ultrasonic technique at varied temperature and time. It has been observed organic cotton fabric dyed using ultrasonic exhaust method at 60oC for 50 minutes gives highest (K/S?max value, excellent fastness property, deeper dye diffusion and less surface deterioration compared to the conventional dyeing method. Moreover, causticized and dyed sample with ultrasonic technique at 60oC for 30 minutes gives colour strength value almost equal to the conventional recommended dyeing method. Hence, dyeing of organic material using ultrasonic exhaust method saves energy and time

  5. Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability

    Science.gov (United States)

    Rani, Babita; Kumar, Vivek; Singh, Jagvijay; Bisht, Sandeep; Teotia, Priyanku; Sharma, Shivesh; Kela, Ritu

    2014-01-01

    Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85%) followed by Nigrosin (77.47%), Malachite green (72.77%) and dye mixture (33.08%) under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15%) followed by Basic fuchsin (89.8%), Malachite green (83.25%) and mixture (78.4%). The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination. PMID:25477943

  6. Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells

    Science.gov (United States)

    Wild, Martin; Griebel, Jan; Hajduk, Anna; Friedrich, Dirk; Stark, Annegret; Abel, Bernd; Siefermann, Katrin R.

    2016-05-01

    The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4‧-(2,2-dicyanovinyl)-[1,1‧-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up.

  7. Limestone reaction in calcium aluminate cement–calcium sulfate systems

    Energy Technology Data Exchange (ETDEWEB)

    Bizzozero, Julien, E-mail: julien.bizzozero@gmail.com; Scrivener, Karen L.

    2015-10-15

    This paper reports a study of ternary blends composed of calcium aluminate cement, calcium sulfate hemihydrate and limestone. Compressive strength tests and hydration kinetics were studied as a function of limestone and calcium sulfate content. The phase evolution and the total porosity were followed and compared to thermodynamic simulation to understand the reactions involved and the effect of limestone on these binders. The reaction of limestone leads to the formation of hemicarboaluminate and monocarboaluminate. Increasing the ratio between sulfate and aluminate decreases the extent of limestone reaction.

  8. Modeling the efficiency of Förster resonant energy transfer from energy relay dyes in dye-sensitized solar cells

    KAUST Repository

    Hoke, Eric T.

    2010-02-11

    Förster resonant energy transfer can improve the spectral breadth, absorption and energy conversion efficiency of dye sensitized solar cells. In this design, unattached relay dyes absorb the high energy photons and transfer the excitation to sensitizing dye molecules by Förster resonant energy transfer. We use an analytic theory to calculate the excitation transfer efficiency from the relay dye to the sensitizing dye accounting for dynamic quenching and relay dye diffusion. We present calculations for pores of cylindrical and spherical geometry and examine the effects of the Förster radius, the pore size, sensitizing dye surface concentration, collisional quenching rate, and relay dye lifetime. We find that the excitation transfer efficiency can easily exceed 90% for appropriately chosen dyes and propose two different strategies for selecting dyes to achieve record power conversion efficiencies. © 2010 Optical Society of America.

  9. Mode coupling in organic dye lasers

    Energy Technology Data Exchange (ETDEWEB)

    Hirth, A.

    1973-10-25

    Saturable dye triggering is discussed together with relaxation time and pulse duration. The influence of stimulated emission is detailed. Experimental results of mode coupling with cyanines and xanthines, flash excited and not, are reported.

  10. Liquid crystal tunable photonic crystal dye laser

    DEFF Research Database (Denmark)

    Buss, Thomas; Christiansen, Mads Brøkner; Smith, Cameron;

    2010-01-01

    We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium....

  11. Preparation and Application of Microencapsulated Disperse Dyes

    Institute of Scientific and Technical Information of China (English)

    罗艳; 陈水林

    2001-01-01

    Microcapsules containing disperse dyes were prepared by means of in-situ polymerization. Polyester fabrics were multiple-transfer printed and color-mix printed using those microencapsulated dyes under different process conditions. By color measurement instrument, it can be seen that the times of multiple-transfer printing are up to ten while under appropriate conditions, especially when the transfer printing time is 50 seconds and the transfer printing temperature is 180°C. On the other hand, the K/S value of each transfer printing can keep almost constant. Meanwhile, the visual effect of color- mix printing with microencapsulated disperse dyes is special in the varicolored exhibiting if compared with conventional disperse dyes.

  12. Phytoremediation in education: textile dye teaching experiments.

    Science.gov (United States)

    Ibbini, Jwan H; Davis, Lawrence C; Erickson, Larry E

    2009-07-01

    Phytoremediation, the use of plants to clean up contaminated soil and water, has a wide range of applications and advantages, and can be extended to scientific education. Phytoremediation of textile dyes can be used as a scientific experiment or demonstration in teaching laboratories of middle school, high school and college students. In the experiments that we developed, students were involved in a hands-on activity where they were able to learn about phytoremediation concepts. Experiments were set up with 20-40 mg L(-1) dye solutions of different colors. Students can be involved in the set up process and may be involved in the experimental design. In its simplest forms, they use two-week-old sunflower seedlings and place them into a test tube of known volume of dye solution. Color change and/or dye disappearance can be monitored by visual comparison or with a spectrophotometer. Intensity and extent of the lab work depends on student's educational level, and time constraints. Among the many dyes tested, Evan's Blue proved to be the most readily decolorized azo dye. Results could be observed within 1-2 hours. From our experience, dye phytoremediation experiments are suitable and easy to understand by both college and middle school students. These experiments help visual learners, as students compare the color of the dye solution before and after the plant application. In general, simple phytoremediation experiments of this kind can be introduced in many classes including biology, biochemistry and ecological engineering. This paper presents success stories of teaching phytoremediation to middle school and college students.

  13. Kinetics of Dyes Adsorbed by Chitosan

    Institute of Scientific and Technical Information of China (English)

    CHEN Liang; CHEN Dong-hui; GAO Liang

    2002-01-01

    A study on adsorption of Acidic Blue RAWL and Cationic Blue X-GRRL dyes by chitosan have been conducted.The adsorption kinetic parameters including adsorption rate K and effective diffusing coefficient D'i under the optimal pH ranges have been determined. Analysis through the enthalpy calculation reveals a substantial thermodynamic difference between the adsorption processes of the two dyes, which helps to understand the adsorption mechanism by chitosan.

  14. Bimanes and Related Heterocycles as Laser Dyes

    Science.gov (United States)

    1991-01-10

    anhydride ) converted anti-(amino,hy- benzoquinone (DDQ) gave syn-(benzo,tetramneth- drogen)bimane 11 to anti-(anino,nitro)bimane 15 ylene)bimnane 27...514 ones) as laser dyes. Kosower introduced a system nm. Presumably helicity, that was demonstrated by of trivial nomenclature for the bimanes based...chloride). Laser activ- nitric acid (90%) and acetic anhydride , converted ity from dyes in polymeric glasses [16] will be de-nitr c ac d (9 9o v rte

  15. Calcium binding protein-mediated regulation of voltage-gated calcium channels linked to human diseases

    Institute of Scientific and Technical Information of China (English)

    Nasrin NFJATBAKHSH; Zhong-ping FENG

    2011-01-01

    Calcium ion entry through voltage-gated calcium channels is essential for cellular signalling in a wide variety of cells and multiple physiological processes. Perturbations of voltage-gated calcium channel function can lead to pathophysiological consequences. Calcium binding proteins serve as calcium sensors and regulate the calcium channel properties via feedback mechanisms. This review highlights the current evidences of calcium binding protein-mediated channel regulation in human diseases.

  16. Removal of Methylene Blue Dye from Synthetic Wastewater with Bone Char

    Directory of Open Access Journals (Sweden)

    Gh Ghanizadeh

    2009-09-01

    Full Text Available "n "n "nBackgrounds and Objectives: Dyes  are  organic  materials  with  complex structures, toxic,  carcinogenic, teratogenic,nonbiodegredable properties and!the most!important pollutants of textile industrial wastewaters. The goal of this study was to survey the feasibility application of bone char (BC as a sorbent for the  of methylene blue (MB from synthetic wastewater.The sub goals of the research!were to determine!the adsorption isotherm, !effects of primary concentration of dye, adsorbent!dose, contact!time, and pH for the adsorption of MB with BC."nMaterials and Methods: BC was prepared under laboratory conditions by using of electrical furnace at 400°C for 2h. The prepared BC was crushed and pulverized by standard ASTM sieves with range of 10-16mesh(1.18-2mm.The  chemical composition  and  solid  structure  of BC was  analyzed using X-ray diffraction(XRD and  scanning  electronic  microscopy (SEM. Measurement  of  the surface area was carried out by N2 gas via BET isotherm and Belsorb software. The concentration of dye was measured by photometric!method (663nm."nResults: Predominant!compositionof BC is calcium hydroxyl apatite (Ca5 (PO43OH with 14m2/g surface area. The results of this study showed that increasing of primary concentration of dye, adsorbent dose and pH (5 to12 would lead to increasing of adsorption/removal of MB dye.Equilibration of dye adsorption was reached at lapse of 2h andoptimum pH for adsorption of MB with BC found in the rage of 8.5-12.Adsorption of MB witht BC complies witht freundlich isotherm(R2:0.99."nConclusion: Bone char is a cheap component that can be used as an adsorbent in water and wastewater treatment. Based on optimum pH of 8.5-12 found for the removal of MB and the fact that many of textile!industrial wastewaters have an alkaline pH, this adsorbent can be!used for the removal of dyes from these wastewaters.

  17. Photocatalytic degradation of synthetic dye under sunlight

    Directory of Open Access Journals (Sweden)

    Mijin Dušan

    2007-01-01

    Full Text Available Synthetic dyes are widely used in the textile industry. Dye pollutants from the textile industry are an important source of environmental contamination. The majority of these dyes are toxic, mostly non-biodegradable and also resistant to decomposition by physico-chemical methods. Among new oxidation methods or "advanced oxidation processes", heterogeneous photocatalysis appears as an emerging destructive technology leading to the total mineralization of many organic pollutants. CI Basic Yellow 28 (BY28, commonly used as a textile dye, could be photocatalytically degraded using TiU2 as catalyst under sunlight. The effect of some parameters such as the initial catalyst concentration, initial dye concentration, initial NaCl and Na2CO3 concentrations, pH, H2O2 and type of catalyst on the degradation rate of BY28 was examined in details. The presence of NaCl and Na2CO3 led to inhibition of the photodegradation process. The highest photodegradation rate was observed at high pH, while the rate was the lowest at low pH. Increase of the initial H2O2 concentration increased the initial BY28 photodegradation efficiency. ZnO was a better catalyst than TiO2 at low dye concentrations.

  18. Degradation of textile dyes by cyanobacteria

    Directory of Open Access Journals (Sweden)

    Priscila Maria Dellamatrice

    Full Text Available Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black, and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.

  19. Calcium signals in olfactory neurons.

    Science.gov (United States)

    Tareilus, E; Noé, J; Breer, H

    1995-11-09

    Laser scanning confocal microscopy in combination with the fluorescent calcium indicators Fluo-3 and Fura-Red was employed to estimate the intracellular concentration of free calcium ions in individual olfactory receptor neurons and to monitor temporal and spatial changes in the Ca(2+)-level upon stimulation. The chemosensory cells responded to odorants with a significant increase in the calcium concentration, preferentially in the dendritic knob. Applying various stimulation paradigma, it was found that in a population of isolated cells, subsets of receptor neurons display distinct patterns of responsiveness.

  20. Optical properties of natural dyes on the dye-sensitized solar cells (DSSC) performance

    Science.gov (United States)

    Pratiwi, D. D.; Nurosyid, F.; Supriyanto, A.; Suryana, R.

    2016-11-01

    This study reported several natural dyes for application in dye-sensitized solar cells (DSSC). This study aims was to determine the effect of optical absorption properties of natural dyes on efficiency of DSSC. The sandwich structure of DSSC consist of TiO2 as working electrode, carbon layer as counter electrode, natural dyes as photosensitizer, and electrolyte as electron transfer media. The natural dyes used in this experiment were extracted from dragon fruit anthocyanin, mangosteen peels anthocyanin, and red cabbage anthocyanin. The absorbance of dyes solutions and the adsorption of the dye on the surface of TiO2 were characterized using UV-Vis spectrophotometer, the quantum efficiency versus wavelength was characterized using incident photon-to-current efficiency (IPCE) measurement system, and the efficiency of DSSC was calculated using I-V meter. UV-Vis characteristic curves showed that wavelength absorption of anthocyanin dye of red cabbage was 450 - 580 nm, anthocyanin of mangosteen peels was 400 - 480 nm, and anthocyanin of dragon fruit was 400 - 650 nm. Absorption spectra of the dye adsorption on the surface of TiO2 which was resulted in the highest absorbance of red cabbage anthocyanin. IPCE characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted quantum efficiency of 0.058%; 0.047%; and 0.043%, respectively at wavelength maximum about 430 nm. I-V characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted efficiency of 0.054%; 0.042%; and 0.024%, respectively.

  1. Chlorine disinfection of dye wastewater: Implications for a commercial azo dye mixture

    Energy Technology Data Exchange (ETDEWEB)

    Vacchi, Francine Inforcato; Albuquerque, Anjaina Fernandes; Vendemiatti, Josiane Aparecida; Morales, Daniel Alexandre [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil); Ormond, Alexandra B.; Freeman, Harold S. [Department of Textile Engineering, Chemistry, and Science, North Carolina State University, Raleigh, NC 27695-8301 (United States); Zocolo, Guilherme Juliao; Zanoni, Maria Valnice Boldrin [Departamento de Quimica Analitica, Universidade Estadual Paulista Julio de Mesquita Filho, Instituto de Quimica de Araraquara, Araraquara, SP 14801-970 (Brazil); Umbuzeiro, Gisela, E-mail: giselau@ft.unicamp.br [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil)

    2013-01-01

    Azo dyes, the most widely used family of synthetic dyes, are often employed as colorants in areas such as textiles, plastics, foods/drugs/cosmetics, and electronics. Following their use in industrial applications, azo dyes have been found in effluents and various receiving waters. Chemical treatment of effluents containing azo dyes includes disinfection using chlorine, which can generate compounds of varying eco/genotoxicity. Among the widely known commercial azo dyes for synthetic fibers is C.I. Disperse Red 1. While this dye is known to exist as a complex mixture, reports of eco/genotoxicity involve the purified form. Bearing in mind the potential for adverse synergistic effects arising from exposures to chemical mixtures, the aim of the present study was to characterize the components of commercial Disperse Red 1 and its chlorine-mediated decoloration products and to evaluate their ecotoxicity and mutagenicity. In conducting the present study, Disperse Red 1 was treated with chlorine gas, and the solution obtained was analyzed with the aid of LC-ESI-MS/MS to identify the components present, and then evaluated for ecotoxicity and mutagenicity, using Daphnia similis and Salmonella/microsome assays, respectively. The results of this study indicated that chlorination of Disperse Red 1 produced four chlorinated aromatic compounds as the main products and that the degradation products were more ecotoxic than the parent dye. These results suggest that a disinfection process using chlorine should be avoided for effluents containing hydrophobic azo dyes such commercial Disperse Red 1. -- Highlights: Black-Right-Pointing-Pointer Aqueous solutions of Disperse Red 1 were treated with chlorine. Black-Right-Pointing-Pointer The chlorination products of Disperse Red 1 were identified using LC-ESI-MS/MS. Black-Right-Pointing-Pointer Daphnia and Salmonella/microsome were employed for eco/genotoxicity testing. Black-Right-Pointing-Pointer The chlorinated dye was more mutagenic

  2. Nucleophilic Addition of Reactive Dyes on Amidoximated Acrylic Fabrics

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    Reda M. El-Shishtawy

    2014-01-01

    Full Text Available Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% owf of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics.

  3. Nucleophilic addition of reactive dyes on amidoximated acrylic fabrics.

    Science.gov (United States)

    El-Shishtawy, Reda M; El-Zawahry, Manal M; Abdelghaffar, Fatma; Ahmed, Nahed S E

    2014-01-01

    Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% of of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics.

  4. 21 CFR 184.1187 - Calcium alginate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium alginate. 184.1187 Section 184.1187 Food... Specific Substances Affirmed as GRAS § 184.1187 Calcium alginate. (a) Calcium alginate (CAS Reg. No. 9005.... Calcium alginate is prepared by the neutralization of purified alginic acid with appropriate pH...

  5. Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

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    Shahid Mahmood

    2011-04-01

    Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

  6. Enzymatic decolorization of spent textile dyeing baths composed by mixtures of synthetic dyes and additives.

    Science.gov (United States)

    Ciullini, Ilaria; Gullotto, Antonella; Tilli, Silvia; Sannia, Giovanni; Basosi, Riccardo; Scozzafava, Andrea; Briganti, Fabrizio

    2012-10-01

    The effects of different components of real dyeing bath formulations, such as the equalizing and fixing additives-acids, salts, and surfactants-on the decolorization catalyzed by Funalia trogii enzymatic extracts, were investigated to understand their influence on the recalcitrance to biodegradation of this type of wastewater. The decolorization of selected dyes and dye mixtures after tissue dyeing was performed in the presence/absence of auxiliary compounds. All spent dyeing baths were enzymatically decolorized to different extents, by the addition of extracts containing laccase only or laccase plus cellobiose dehydrogenase. Whereas surfactant auxiliaries, in some instances, inhibit the decolorization of spent dyeing baths, in several occurrences the acid/salt additives favor the enzymatic process. In general, the complete spent dyeing formulations are better degraded than those containing the dyes only. The comparison of extracellular extracts obtained from spent straws from the commercial growth of Pleurotus sp. mushrooms with those from F. trogii reveals similar decolorization extents thus allowing to further reduce the costs of bioremediation.

  7. Synthesis and dyeing properties of new disazo disperse dyes for polyester and nylon fabrics

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    Tarulata B. Shah

    2014-12-01

    Full Text Available Diazotized aryl amines were coupled with two stenhouse salt namely, N-(5-phenylamino-penta-4-ol-2,4-diene-1-ylideneanilines hydrochloride [S1 (RH or S2 (ROH] to furnish two series of disazo disperse dyes (S1D1–10 and S2D1–10. The structure of all the dyes was established by estimating number of azo groups, elemental analysis and spectral studies (IR, 1H-NMR, UV/Visible. The structure–property relationship was discussed by using electronic absorption spectra of the dyes. These dyes were applied to polyester and nylon fabrics as disperse dyes by using temperature exhaust dyeing method. The relevant dyeing characteristics, such as dyeability on fabrics, wash-fastness and light-fastness were evaluated. Fabrics dyed with these dyes furnished generally deep and bright intense hues ranging from light yellow to orange to reddish brown. The color fastness of the dyed fabric was assessed by determining wash-fastness and light-fastness properties.

  8. DYEING COTTON WITH EISENIA BICYCLIS AS NATURAL DYE USING DIFFERENT BIOMORDANTS

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    BONET Mª Ángeles

    2015-05-01

    Full Text Available Natural dyes are known for their use in coloring of food substrate, leather as well as natural protein fibers like wool, silk and cotton as major areas of application since pre-historic times. Nowadays, there has been revival of the growing interest on the application of natural dyes on natural fibers due to worldwide environmental consciousness. Some researchers focus their studies on the improvement of these dyes using mordants. Most works use metallic mordants like aluminum or iron are used, but some of them are hazardous. In this work we used a biomordant to solve environmental problems caused by metallic mordants. The effects of chitosan weight molecular in mordanting on the dyeing characteristics and the UV protection property were examined in this study. Chitosan mordanted Eisenia Bicyclis dyed cotton showed better dyeing characteristic and higher UV protection property compared with undyed cotton fabric. To analyze the differences of the dyeing, reflection spectrophotometer was used, evaluating the results of CIELAB color difference values and the strength color (in terms of K/S value. We conclude that the type of chitosan used affect the dyeing efficiency and the UV protection, showing different behavior between dye sample using chitosan with low or medium molecular weight.

  9. Ethoxy-substituted Oligo-phenylenevinylene-Bridged Organic Dyes for Efficient Dye-Sensitized Solar Cells

    Institute of Scientific and Technical Information of China (English)

    单益凡; 汤杰; 赖华; 谭宏伟; 刘晓峰; 杨帆; 房强

    2012-01-01

    Organic dyes with ethoxy-substituted oligo-phenylenevinylene as chromophores were synthesized for dye-sensitized solar cells (DSSCs), and the detailed relationships between the dye structures, photophysical properties, electrochemical properties, and performances of DSSCs were described. The dye S3O showed broad IPCE spectra in the spectral range of 350--750 nm, and the dye S1P showed solar energy-to-electricity conversion efficiency (1/) of up to 4.23% under AM 1.5 irradiation (100 mW/cm2) in comparison with the reference Ru-complex (N719 dye) with an r/value of 5.90% under similar experimental conditions.

  10. Molecular design and photovoltaic performance of organic dyes containing phenothiazine for dye-sensitized solar cells.

    Science.gov (United States)

    Jo, Hyo Jeong; Nam, Jung Eun; Sim, Kyoseung; Kim, Dae-Hwan; Kim, Jae Hong; Kang, Jin-Kyu

    2014-10-01

    We synthesized novel organic photosensitizers based on fluorine-substituted phenothiazine with thiophene bridge units in the chromophore for application in dye-sensitized solar cells (DSSCs). Furthermore, organic dyes with different acceptors exhibited higher molar extinction coefficients, and better light absorption at longer wavelengths. The photovoltaic properties of organic dyes composed of different acceptors in their chromophores were measured to identify their effects on the DSSC performance. The organic dye, PFSCN2 containing multi-cyanoacrylic acid as the electron acceptor, showed a power conversion efficiency of 4.67% under AM 1.5 illumination (100 mW/cm2). The retarded recombination kinetics from TiO2 electrode to electrolyte enhanced the electron life time of the organic dye, PFSCN2 in the photoanode of the DSSC. This was confirmed with impedance analysis.

  11. Chemosensors and biosensors based on polyelectrolyte microcapsules containing fluorescent dyes and enzymes.

    Science.gov (United States)

    Kazakova, Lyubov I; Shabarchina, Lyudmila I; Anastasova, Salzitsa; Pavlov, Anton M; Vadgama, Pankaj; Skirtach, Andre G; Sukhorukov, Gleb B

    2013-02-01

    The concept of enzyme-assisted substrate sensing based on use of fluorescent markers to detect the products of enzymatic reaction has been investigated by fabrication of micron-scale polyelectrolyte capsules containing enzymes and dyes in one entity. Microcapsules approximately 5 μm in size entrap glucose oxidase or lactate oxidase, with peroxidase, together with the corresponding markers Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) dichloride (Ru(dpp)) complex and dihydrorhodamine 123 (DHR123), which are sensitive to oxygen and hydrogen peroxide, respectively. These capsules are produced by co-precipitation of calcium carbonate particles with the enzyme followed by layer-by-layer assembly of polyelectrolytes over the surface of the particles and incorporation of the dye in the capsule interior or in the multilayer shell. After dissolution of the calcium carbonate the enzymes and dyes remain in the multilayer capsules. In this study we produced enzyme-containing microcapsules sensitive to glucose and lactate. Calibration curves based on fluorescence intensity of Ru(dpp) and DHR123 were linearly dependent on substrate concentration, enabling reliable sensing in the millimolar range. The main advantages of using these capsules with optical recording is the possibility of building single capsule-based sensors. The response from individual capsules was observed by confocal microscopy as increasing fluorescence intensity of the capsule on addition of lactate at millimolar concentrations. Because internalization of the micron-sized multi-component capsules was feasible, they could be further optimized for in-situ intracellular sensing and metabolite monitoring on the basis of fluorescence reporting.

  12. The Effect of Calcium Hydroxide As an Intracanal Medication of The Apical Microleakage

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    Heshmat Mohajer AR

    2011-12-01

    Full Text Available Background and Aims: Nowadays, calcium hydroxide is used as a dressing for canal sterilization and repair progression of apical lesions. The aim of this study was to investigate the effect of calcium hydroxide as an intracanal medicament on the apical microleakage of root filling.Materials and Methods: In this experimental study, 46 extracted single-rooted human teeth were instrumented with step-back technique to master apical file (MAF size 35. Specimens were randomly divided into 2 groups (n = 20. In group 1, the specimens were treated with calcium hydroxide intracanal medication; and in group 2, the samples did not receive any medication. The teeth were incubated in 100% humidity at 37°C for one week. After that, calcium hydroxide was removed using irrigation with normal saline and reaming with MAF. The root canals were obturated with gutta- percha and AH26 sealer using lateral compaction technique. Specimens were incubated in 100% humility at 37°C for 72 hours and then immersed in India ink for 1 week. Finally, the teeth were cleared and the maximum linear dye penetration was measured under a stereomicroscope at 4X magnification. The data were analyzed by T-test and Chi-square.Results: There was no significant difference between the two experimental groups (P=0.068. Conclusion: The findings of this study indicated that using calcium hydroxide as an intracanal medicament did not influence the apical microleakage after final obturation of the root canal system.

  13. Calcium transients in skeletal muscle fibres under isometric conditions and during and after a quick stretch.

    Science.gov (United States)

    Haugen, P

    1991-12-01

    The transient change in the sarcoplasmic concentration of Ca2+ was measured in intact fibres isolated from the anterior tibial muscle of the frog Litoria moorei. The fibres had been injected with the calcium-sensitive dye arsenazo III and the change of the calcium concentration was calculated from the changes in light absorbance at 570, 600 and 720 nm wavelengths. Absorbance and force were measured under three different conditions: (1) during a normal isometric twitch, (2) when a quick ramp-and-hold stretch had been applied to the fibre during onset of the contraction, and (3) when the fibre was allowed to contract isometrically at a length corresponding to the final length of the stretch. A method was devised to neutralize most of the movement artefacts encountered in such measurements. While the quick stretch caused substantial increase in the level and the duration of the contractile force such as originally described in whole muscle by A. V. Hill, the calcium transients appeared basically unaffected. It thus seems that the mechanism behind the phenomenon of the force enhancement lies at a step in the excitation-contraction coupling subsequent to the calcium release. From the present results, however, it is not clear whether the phenomenon is caused by an increase in the level of activation of the calcium-dependent regulatory system, or whether it is to be found in the acto-myosin interaction itself. The latter alternative would be consistent with the stiffness measurements published earlier.

  14. Relationship between sealing ability of Activ GP and Gutta Flow and methods of calcium hydroxide removal

    Directory of Open Access Journals (Sweden)

    Vineeta Nikhil

    2012-01-01

    Full Text Available Aim: To evaluate the effect of method of calcium hydroxide intracanal dressing removal, on sealing ability of Gutta Flow and Activ GP. Materials and Methods: Seventy extracted mandibular premolars were sectioned at CEJ and canals were prepared with profile 4% rotary file till #40. Canals were filled with calcium hydroxide, coronally sealed with Cavit G and stored at 37°C. After 7 days, samples were divided on the basis of calcium hydroxide removal method (Master apical file, Navi Tip FX, and F File and obturating material (Activ GP and Gutta Flow. Three coats of nail polish were applied except 2 mm around apical foramen and samples were immersed in India ink dye, sectioned, and observed under stereomicroscope for microleakage. Results: The results were statistically analyzed with one way ANOVA-F with Tukey HSD test with the null hypothesis set as 5%. Conclusions: The seal of the canal system was adversely impacted by residual calcium hydroxide when Activ GP and Gutta Flow were used as obturating material and the sealing ability of Activ GP and Gutta Flow was better when MAF was used for removal of calcium hydroxide than F file or Navi tip FX.

  15. Unexpected radiation hazard in dyes of textiles.

    Science.gov (United States)

    Abdel Ghany, Hayam A; Ibrahim, Eman M

    2014-01-01

    Textile dyes are among the most problematic pollutants because of their toxicity on several organisms and ecosystems. Many of the chemicals used in the textile industry may represent some health concerns. The determination of the radioactivity in textile dyes is therefore very important for both human health and environment. The study was designated to determine, for the first time, the values of (238)U, (232)Th and (40)K in nine different dyes employed in the textile industry using gamma spectrometry with a Hyper Pure Germanium (HPGe) detector. The mean activity concentrations of (238)U, (232)Th and (40)K were 29.37 ± 4.48, 1.15 ± 0.13 and 565 ± 4 Bq/kg, respectively. The calculated radium equivalents for all samples were lower than the maximum admissible value (370 Bq/kg). The absorbed dose rates due to the natural radioactivity of the investigated samples ranged from 2.94 ± 0.05 to 166 ± 3 nGy/h. So, the absorbed dose rates for all samples of textile dyes were lower than the international recommended value (55 nGy/h) except the yellow dye (166 ± 3 nGy/h), which recorded a significant radiological hazard. The external hazard index was also calculated. Conclusively, the results have indicated that the textile dyes may possess a measurable amount of radioactivity that should be taken into account. Therefore, safety rules and precautions should be applied for dyes used in the textile industry and for people working in this field.

  16. Calcium Orthophosphate Cements and Concretes

    Directory of Open Access Journals (Sweden)

    Sergey V. Dorozhkin

    2009-03-01

    Full Text Available In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are a bioactive and biodegradable grafting material in the form of a powder and a liquid. Both phases form after mixing a viscous paste that after being implanted, sets and hardens within the body as either a non-stoichiometric calcium deficient hydroxyapatite (CDHA or brushite, sometimes blended with unreacted particles and other phases. As both CDHA and brushite are remarkably biocompartible and bioresorbable (therefore, in vivo they can be replaced with newly forming bone, calcium orthophosphate cements represent a good correction technique for non-weight-bearing bone fractures or defects and appear to be very promising materials for bone grafting applications. Besides, these cements possess an excellent osteoconductivity, molding capabilities and easy manipulation. Furthermore, reinforced cement formulations are available, which in a certain sense might be described as calcium orthophosphate concretes. The concepts established by calcium orthophosphate cement pioneers in the early 1980s were used as a platform to initiate a new generation of bone substitute materials for commercialization. Since then, advances have been made in the composition, performance and manufacturing; several beneficial formulations have already been introduced as a result. Many other compositions are in experimental stages. In this review, an insight into calcium orthophosphate cements and concretes, as excellent biomaterials suitable for both dental and bone grafting application, has been provided.

  17. The effect of dendrimer on cotton dyeability with direct dyes

    Directory of Open Access Journals (Sweden)

    Khakzar Bafrooei F.

    2014-01-01

    Full Text Available Pretreatment of cotton fabric with poly(propylene imine dendrimer enhanced its colour strength using C.I. Direct Red 81 and C.I. Direct Blue 78. Application of this dendrimer and the direct dye simultaneously on cotton fabric by the exhaust and the continuous dyeing method were studied; slight improvements in the dyeing results were obtained. Pretreatment of the cotton fabric with dendrimer in an emulsion form using the pad-dry method followed by continuous dyeing markedly increased the colour strength. In addition, level dyeing was obtained, and no negative effects on the fastness properties of the dyes used were observed.

  18. Review of Recent Progress in Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Fan-Tai Kong

    2007-08-01

    Full Text Available We introduced the structure and the principle of dye-sensitized solar cell (DSC. The latest results about the critical technology and the industrialization research on dye-sensitized solar cells were reviewed. The development of key components, including nanoporous semiconductor films, dye sensitizers, redox electrolyte, counter electrode, and conducting substrate in dye-sensitized solar cells was reviewed in detail. The developing progress and prospect of dye-sensitized solar cells from small cells in the laboratory to industrialization large-scale production were reviewed. At last, the future development of DSC was prospective for the tendency of dye-sensitized solar cells.

  19. Preparation of P(St-BA-VBT)/dye Colored Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    HAN Dong-mei; FANG Kuan-jun

    2015-01-01

    P (St-BA-VBT)/dye colored nanoparticles were prepared by staining P (Styrene-Butyl Acrylate-VinylBenzyl Trimethylammonium chloride) nanoparticles synthesized by soap free cationic emulsion polymerization with reactive dyes. The effects of reactive dyes dosage, dyeing temperature and time on amounts of dyes adsorbed on the nanoparticles were analysed. Results showed that when Reactive Red 195 dosage was 5.25%, the adsorption amounts of dyes on the nanoparticles reached a maximum value of 18.64 mg/g at 65℃for 90 min.

  20. Factors affecting calcium balance in Chinese adolescents.

    Science.gov (United States)

    Yin, Jing; Zhang, Qian; Liu, Ailing; Du, Weijing; Wang, Xiaoyan; Hu, Xiaoqi; Ma, Guansheng

    2010-01-01

    Chinese dietary reference intakes (DRIs) for calcium were developed mainly from studies conducted amongst Caucasians, yet a recent review showed that reference calcium intakes for Asians are likely to be different from those of Caucasians (Lee and Jiang, 2008). In order to develop calcium DRIs for Chinese adolescents, it is necessary to explore the characteristics and potential influencing factors of calcium metabolic balance in Chinese adolescents. A total of 80 students (15.1+/-0.8 years) were recruited stratified by gender from a 1-year calcium supplementation study. Subjects were randomly designed to four groups and supplemented with calcium carbonate tablets providing elemental calcium at 63, 354, 660, and 966 mg/day, respectively. Subjects consumed food from a 3-day cycle menu prepared by staff for 10 days. Elemental calcium in samples of foods, feces, and urine was determined in duplicates by inductively coupled plasma atomic emission spectrometry. The total calcium intake ranged from 352 to 1323 mg/day. The calcium apparent absorption efficiency and retention in boys were significantly higher than that in girls (68.7% vs. 46.4%, 480 mg/day vs. 204 mg/day, PCalcium retention increased with calcium intakes, but did not reach a plateau. Calcium absorption efficiency in boys increased with calcium intake up to 665 mg/day, and decreased after that. In girls, calcium absorption efficiency decreased with calcium intake. Calcium absorption efficiency increased within 1 year after first spermatorrhea in boys, but decreased with pubertal development in girls. Sex, calcium intake, age, and pubertal development were the most important determinants of calcium absorption (R(2)=0.508, Pcalcium intake, age, and pubertal development are important factors for calcium retention and absorption during growth, which should be considered for the development of calcium DRIs for Chinese adolescents.

  1. Quantification of alginate by aggregation induced by calcium ions and fluorescent polycations.

    Science.gov (United States)

    Zheng, Hewen; Korendovych, Ivan V; Luk, Yan-Yeung

    2016-01-01

    For quantification of polysaccharides, including heparins and alginates, the commonly used carbazole assay involves hydrolysis of the polysaccharide to form a mixture of UV-active dye conjugate products. Here, we describe two efficient detection and quantification methods that make use of the negative charges of the alginate polymer and do not involve degradation of the targeted polysaccharide. The first method utilizes calcium ions to induce formation of hydrogel-like aggregates with alginate polymer; the aggregates can be quantified readily by staining with a crystal violet dye. This method does not require purification of alginate from the culture medium and can measure the large amount of alginate that is produced by a mucoid Pseudomonas aeruginosa culture. The second method employs polycations tethering a fluorescent dye to form suspension aggregates with the alginate polyanion. Encasing the fluorescent dye in the aggregates provides an increased scattering intensity with a sensitivity comparable to that of the conventional carbazole assay. Both approaches provide efficient methods for monitoring alginate production by mucoid P. aeruginosa.

  2. Selectivity and specificity of small molecule fluorescent dyes/probes used for the detection of Zn2+ and Ca2+ in cells.

    Science.gov (United States)

    Figueroa, Julio A Landero; Vignesh, Kavitha Subramanian; Deepe, George S; Caruso, Joseph

    2014-02-01

    Fluorescent dyes are widely used in the detection of labile (free or exchangeable) Zn(2+) and Ca(2+) in living cells. However, their specificity over other cations and selectivity for detection of labile vs. protein-bound metal in cells remains unclear. We characterized these important properties for commonly used Zn(2+) and Ca(2+) dyes in a cellular environment. By tracing the fluorescence emission signal along with UV-Vis and size exclusion chromatography-inductively coupled plasma mass spectrometry (SEC-ICP-MS) in tandem, we demonstrated that among the dyes used for Zn(2+), Zinpyr-1 fluoresces in the low molecular mass (LMM) region containing labile Zn(2+), but also fluoresces in different molecular mass regions where zinc ion is detected. However, FluoZin™-3 AM, Newport Green™ DCF and Zinquin ethyl ester display weak fluorescence, lack of metal specificity and respond strongly in the high molecular mass (HMM) region. Four Ca(2+) dyes were studied in an unperturbed cellular environment, and two of these were tested for binding behavior under an intracellular Ca(2+) release stimulus. A majority of Ca(2+) was in the labile form as tested by SEC-ICP-MS, but the fluorescence from Calcium Green-1™ AM, Oregon Green® 488 BAPTA-1, Fura red™ AM and Fluo-4 NW dyes in cells did not correspond to free Ca(2+) detection. Instead, the dyes showed non-specific fluorescence in the mid- and high-molecular mass regions containing Zn, Fe and Cu. Proteomic analysis of one of the commonly seen fluorescing regions showed the possibility for some dyes to recognize Zn and Cu bound to metallothionein 2. These studies indicate that Zn(2+) and Ca(2+) binding dyes manifest fluorescence responses that are not unique to recognition of labile metals and bind other metals, leading to suboptimal specificity and selectivity.

  3. Chromed Leather Dyeing Peculiarities when Deliming with Peracetic Acid

    Directory of Open Access Journals (Sweden)

    Kęstutis BELEŠKA

    2013-05-01

    Full Text Available The research was aimed to investigate the influence of deliming with peracetic acid on leather dyeing kinetics. Hydrophobic C.I. Acid Red 213 and hydrophilic C.I. Acid Red 423 dyes were used. Sorption of dye depends on hydrophobicity/hydrophility of dye and dyeing temperature. Equilibrium of process is reached faster using hydrophobic C.I. Acid Red 213 at 45 ºC. However, both control and experimental leather fibres adsorb more hydrophilic dye C.I. Acid Red 423 and this fact does not depend on temperature. The diffusion coefficient of dye C.I. Acid Red 423 calculated according to Weisz model is higher when dyeing conventional leather. The change of deliming method has influence on chromed leather dyeing but this influence is not significant. The adsorption ability of control leather fibres at 30 ºC and 45 ºC is higher using both dyes as compared to the dyeing the experimental one. The increase of dyeing temperature increases the adsorption ability independently on the sort of leather fibres. Such dependence of the adsorption ability on the temperature shows that hydrophobic action and van der Waals forces prevail between dye and fibres during dyeing process. The Gibbs energy changes show that adsorption of both dyes by leather fibres independently on their sort is a spontaneous process. The affinity of both dyes to conventional leather fibres is higher comparing with experimental one. The change of enthalpy is positive in all cases, and it means that the driving force of the dyeing is the change of entropy.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4431

  4. 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.

  5. ADSORPTION OF DYES ON ACTIVATED CARBON FIBERS

    Institute of Scientific and Technical Information of China (English)

    ChenShuixia; WuChangqing; 等

    1998-01-01

    The adsorption behavior of dyes on a variety of sisal based activated carbon fibers (SACF) has been studied in this paper. The results show that this kind of ACF has excellent adsorption capacities for some organic (dye) molecules.SACF can remove nearly all methylene blue,crystal violet,bromophenol blue and Eriochrome blue black R from water after static adsorption for 24h. at 30℃. The adsorption amounts can reach more than 400mg/g when adding 50 mg SACF into 50 ml dye solution.Under the same conditions,the adsorption amounts of xylenol orange fluorescein and Eriochrome black T wree lower.On the other hand,the adsorption amounts change along with the characteristics of adsorbents.The SACFs activated above 840℃,which have higher specific surface areas and wider pore radii,have higher adsorption amounts for the dyes.The researching results also show that the adsorption rates of dyes onto SACFs decrease by the order of methylene blue,Eriochrome blue black R and crystal violet.

  6. Physical and chemical investigations on natural dyes

    Science.gov (United States)

    Acquaviva, S.; D'Anna, E.; de Giorgi, M. L.; Della Patria, A.; Baraldi, P.

    2010-09-01

    Natural dyes have been used extensively in the past for many purposes, such us to colour fibers and to produce inks, watercolours and paints, but their use declined rapidly after the discovery of synthetic colours. Nowadays we witness a renewed interest, as natural dyes are neither toxic nor polluting. In this work, physical and chemical properties of four selected dyes, namely red (Madder), yellow (Weld and Turmeric) and blue (Woad) colours, produced by means of traditional techniques at the Museo dei Colori Naturali (Lamoli, Italy), have been investigated. The chromatic properties have been studied through the reflectance spectroscopy, a non-invasive technique for the characterisation of chromaticity. Reflection spectra both from powders and egg-yolk tempera models have been acquired to provide the typical features of the dyes in the UV-vis spectral range. Moreover, to assess the feasibility of laser cleaning procedures, tempera layers were investigated after irradiation with an excimer laser. Micro Raman spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-Ray analyses have complemented the survey, returning compositional and morphological information as well. Efforts have been made to give scientific feedback to the production processes and to support the research activity in the restoration of the artworks where these dyes were employed.

  7. Dyes and Materials for Sensitised Electrochemical Photovoltaics

    Science.gov (United States)

    Amirnasr, M.; Brooks, K. G.; McEvoy, A. J.; Nazeeruddin, M. K.; Pechy, P.; Thampi, K. R.; Grätzel, M.

    2001-11-01

    The present concepts evolved in the context of research and development of artificial photosynthetic systems. Our biosphere depends totally on the action of a porphyrin dye, chlorophyll, for its continued existance, since all food resources find their origin in photosynthesis. Equally, for much of our energy resources we rely on the same process, present or past, as stored in fossil fuels. Naturally, therefore, when it comes to the molecular design of dyes for solar photochemical applications the reference to the porphyrins and similar organometallic complexes based on nitrogen ring structures as prototypes is obvious. However, although nature confines itself to magnesium and iron for its principal pigments, chlorophyll and haemoglobin respectively, the synthetic chemist can access the whole range of metallic elements. The use of ruthenium pyridyl complexes has almost thirty years of development history, and although other compounds have been assessed, such as zinc porphyrins and even prussian-blue analogues, the most suitable dyes today are still modifications of the ruthenium-based pyridyl complexes. The molecular engineering of dyes extends the visible spectrum response, enhances stability and promotes chemisorption to oxide semiconductor substrates while maintaining the energetics and kinetics for efficient charge transfer to function in sensitised electrochemical photovoltaic devices. There is also an overview of the present status of the technology, the materials incorporated in current devices, and their reliability in practical applications especially in situations of thermal stress. The conclusion will present the case for ongoing development of dye-sensitised systems in photovoltaic technology.

  8. Mitochondrial calcium uptake.

    Science.gov (United States)

    Williams, George S B; Boyman, Liron; Chikando, Aristide C; Khairallah, Ramzi J; Lederer, W J

    2013-06-25

    Calcium (Ca(2+)) uptake into the mitochondrial matrix is critically important to cellular function. As a regulator of matrix Ca(2+) levels, this flux influences energy production and can initiate cell death. If large, this flux could potentially alter intracellular Ca(2+) ([Ca(2+)]i) signals. Despite years of study, fundamental disagreements on the extent and speed of mitochondrial Ca(2+) uptake still exist. Here, we review and quantitatively analyze mitochondrial Ca(2+) uptake fluxes from different tissues and interpret the results with respect to the recently proposed mitochondrial Ca(2+) uniporter (MCU) candidate. This quantitative analysis yields four clear results: (i) under physiological conditions, Ca(2+) influx into the mitochondria via the MCU is small relative to other cytosolic Ca(2+) extrusion pathways; (ii) single MCU conductance is ∼6-7 pS (105 mM [Ca(2+)]), and MCU flux appears to be modulated by [Ca(2+)]i, suggesting Ca(2+) regulation of MCU open probability (P(O)); (iii) in the heart, two features are clear: the number of MCU channels per mitochondrion can be calculated, and MCU probability is low under normal conditions; and (iv) in skeletal muscle and liver cells, uptake per mitochondrion varies in magnitude but total uptake per cell still appears to be modest. Based on our analysis of available quantitative data, we conclude that although Ca(2+) critically regulates mitochondrial function, the mitochondria do not act as a significant dynamic buffer of cytosolic Ca(2+) under physiological conditions. Nevertheless, with prolonged (superphysiological) elevations of [Ca(2+)]i, mitochondrial Ca(2+) uptake can increase 10- to 1,000-fold and begin to shape [Ca(2+)]i dynamics.

  9. Quantum dot-dye hybrid systems for energy transfer applications

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Ting

    2010-07-01

    In this thesis, we focus on the preparation of energy transfer-based quantum dot (QD)-dye hybrid systems. Two kinds of QD-dye hybrid systems have been successfully synthesized: QD-silica-dye and QD-dye hybrid systems. In the QD-silica-dye hybrid system, multishell CdSe/CdS/ZnS QDs were adsorbed onto monodisperse Stoeber silica particles with an outer silica shell of thickness 2-24 nm containing organic dye molecules (Texas Red). The thickness of this dye layer has a strong effect on the total sensitized acceptor emission, which is explained by the increase in the number of dye molecules homogeneously distributed within the silica shell, in combination with an enhanced surface adsorption of QDs with increasing dye amount. Our conclusions were underlined by comparison of the experimental results with Monte-Carlo simulations, and by control experiments confirming attractive interactions between QDs and Texas Red freely dissolved in solution. New QD-dye hybrid system consisting of multishell QDs and organic perylene dyes have been synthesized. We developed a versatile approach to assemble extraordinarily stable QD-dye hybrids, which uses dicarboxylate anchors to bind rylene dyes to QD. This system yields a good basis to study the energy transfer between QD and dye because of its simple and compact design: there is no third kind of molecule linking QD and dye; no spacer; and the affinity of the functional group to the QD surface is strong. The FRET signal was measured for these complexes as a function of both dye to QD ratio and center-to-center distance between QD and dye by controlling number of covered ZnS layers. Data showed that fluorescence resonance energy transfer (FRET) was the dominant mechanism of the energy transfer in our QD-dye hybrid system. FRET efficiency can be controlled by not only adjusting the number of dyes on the QD surface or the QD to dye distance, but also properly choosing different dye and QD components. Due to the strong stability, our QD-dye

  10. Improved Reactive Dye-fixation in Pad-Steam Process of Dyeing Cotton Fabric Using Tetrasodium N, NBiscarboxylatomethyl- L-Glutamate

    OpenAIRE

    Awais Khatri; Mazhar Hussain Peerzada

    2012-01-01

    Pad steam process of dyeing cotton with reactive dyes is known to give lower levels of dye-fixation on the fiber because of excessive dye-hydrolysis. This research presents improved reactive dye-fixation in padsteam process of dyeing cotton found in an effort of using biodegradable organic salts to improve the effluent quality. The CI Reactive Blue 250, a bissulphatoethylsulphone dye and the Tetrasodium N, Nbiscarboxylatomethyl- L-Glutamate, a biodegradable organic salt, were used...

  11. Dopaminergic regulation of dendritic calcium: fast multisite calcium imaging.

    Science.gov (United States)

    Zhou, Wen-Liang; Oikonomou, Katerina D; Short, Shaina M; Antic, Srdjan D

    2013-01-01

    Optimal dopamine tone is required for the normal cortical function; however it is still unclear how cortical-dopamine-release affects information processing in individual cortical neurons. Thousands of glutamatergic inputs impinge onto elaborate dendritic trees of neocortical pyramidal neurons. In the process of ensuing synaptic integration (information processing), a variety of calcium transients are generated in remote dendritic compartments. In order to understand the cellular mechanisms of dopaminergic modulation it is important to know whether and how dopaminergic signals affect dendritic calcium transients. In this chapter, we describe a relatively inexpensive method for monitoring dendritic calcium fluctuations at multiple loci across the pyramidal dendritic tree, at the same moment of time (simultaneously). The experiments have been designed to measure the amplitude, time course and spatial extent of action potential-associated dendritic calcium transients before and after application of dopaminergic drugs. In the examples provided here the dendritic calcium transients were evoked by triggering the somatic action potentials (backpropagation-evoked), and puffs of exogenous dopamine were applied locally onto selected dendritic branches.

  12. Formation of calcium complexes by borogluconate in vitro and during calcium borogluconate infusion in sheep.

    Science.gov (United States)

    Farningham, D A

    1985-07-01

    The effect of borogluconate on plasma calcium fractions was studied in vitro and in vivo in sheep. In vitro calcium chloride was more effective in raising ionised plasma calcium than calcium borogluconate. Sodium borate or gluconate added to blood caused only small decreases in blood ionised calcium. However, together, a synergistic reduction in ionised calcium was observed. Following calcium borogluconate infusions into sheep, total plasma calcium rose primarily because of an increase in the unionised ultrafiltrable fraction. Other changes observed following the infusion were hypercalciuria, decreased glomerular filtration rate and acidosis. Sodium borogluconate administered subcutaneously lowered total plasma calcium. This probably resulted from enhanced calcium excretion. It is suggested that since the anionic component of calcium solutions alters the availability and retention of calcium, it is likely to affect clinical efficacy significantly.

  13. [Calcium metabolism characteristics in microgravity].

    Science.gov (United States)

    Grigor'ev, A I; Larina, I M; Morukov, B V

    1999-06-01

    The results of research of calcium exchange parameters at cosmonauts taken part in long space flights (SF) onboard of orbital stations "SALUT" and "MIR" within 1978-1998 were generalized. The analysis of data received during observation of 44 cosmonauts (18 of them have taken part in long SF twice) was done. The observation was carried out before and after SF by duration 30-438 days. The content of a total calcium in blood serum was increased basically by the increase of its ionized fraction after flights of moderate (3-6 months) and large duration (6-14 months) along with the significant increase of PTH and decrease of calcitonin levels. The content of osteocalcin after SF was increased. Three cosmonauts participated in research of calcium kinetics using stable isotopes before, in time and after a 115-day SF. Reduction of intestinal absorption, excretion through a gastrointestinal tract, and increase of calcium excretion with urine were marked in time of SF. In early postflight period a level of intestinal absorption, on the average, was much lower than in SF, and the calcium removal through intestine was increased. Both renal and intestinal excretion of calcium were not normalized in 3.5-4.5 months after end of SF. Increase of resorbtive processes in bone tissues which induced negative bone balance during flight was observed in all test subjects, proceeding from estimations of speed of the basic calcium flows made on the basis of mathematical modeling. The conclusion about decrease in speed of bone tissue remodeling and strengthening of its resorption proves to be true by data of research of biochemical and endocrine markers.

  14. Calcium wave of tubuloglomerular feedback.

    Science.gov (United States)

    Peti-Peterdi, János

    2006-08-01

    ATP release from macula densa (MD) cells into the interstitium of the juxtaglomerular (JG) apparatus (JGA) is an integral component of the tubuloglomerular feedback (TGF) mechanism that controls the glomerular filtration rate. Because the cells of the JGA express a number of calcium-coupled purinergic receptors, these studies tested the hypothesis that TGF activation triggers a calcium wave that spreads from the MD toward distant cells of the JGA and glomerulus. Ratiometric calcium imaging of in vitro microperfused isolated JGA-glomerulus complex dissected from rabbits was performed with fluo-4/fura red and confocal fluorescence microscopy. Activation of TGF by increasing tubular flow rate at the MD rapidly produced a significant elevation in intracellular Ca(2+) concentration ([Ca(2+)](i)) in extraglomerular mesangial cells (by 187.6 +/- 45.1 nM) and JG renin granular cells (by 281.4 +/- 66.6 nM). Subsequently, cell-to-cell propagation of the calcium signal at a rate of 12.6 +/- 1.1 microm/s was observed upstream toward proximal segments of the afferent arteriole and adjacent glomeruli, as well as toward intraglomerular elements including the most distant podocytes (5.9 +/- 0.4 microm/s). The same calcium wave was observed in nonperfusing glomeruli, causing vasoconstriction and contractions of the glomerular tuft. Gap junction uncoupling, an ATP scavenger enzyme cocktail, and pharmacological inhibition of P(2) purinergic receptors, but not adenosine A(1) receptor blockade, abolished the changes in [Ca(2+)](i) and propagation of the calcium wave. These studies provided evidence that both gap junctional communication and extracellular ATP are integral components of the TGF calcium wave.

  15. Pad ultrasonic batch dyeing of causticized lyocell fabric with reactive dyes.

    Science.gov (United States)

    Babar, Aijaz Ahmed; Peerzada, Mazhar Hussain; Jhatial, Abdul Khalique; Bughio, Noor-Ul-Ain

    2017-01-01

    Conventionally, cellulosic fabric dyed with reactive dyes requires significant amount of salt. However, the dyeing of a solvent spun regenerated cellulosic fiber is a critical process. This paper presents the dyeing results of lyocell fabrics dyed with conventional pad batch (CPB) and pad ultrasonic batch (PUB) processes. The dyeing of lyocell fabrics was carried out with two commercial dyes namely Drimarine Blue CL-BR and Ramazol Blue RGB. Dyeing parameters including concentration of sodium hydroxide, sodium carbonate and dwell time were compared for the two processes. The outcomes show that PUB dyed samples offered reasonably higher color yield and dye fixation than CPB dyed samples. A remarkable reduction of 12h in batching time, 18ml/l in NaOH and 05g/l in Na2CO3 quantity was observed for PUB processed samples producing similar results compared to CPB process, making PUB a more economical, productive and an environment friendly process. Color fastness examination witnessed identical results for both PUB and CPB methods. No significant change in surface morphology of PUB processed samples was observed through scanning electron microscope (SEM) analysis.

  16. π-Spacer effect in dithiafulvenyl-π-phenothiazine dyes for dye-sensitized solar cells

    Science.gov (United States)

    Zhang, Xiaofeng; Gou, Faliang; Zhao, Dongning; Shi, Jian; Gao, Hong; Zhu, Zhenping; Jing, Huanwang

    2016-08-01

    New dithiafulvenyl-π-phenothiazine dyes have been devised and prepared for dye-sensitized solar cells. Various π-spacers have been successfully introduced into the skeleton of dithiafulvenyl and phenothiazine unit to generate novel D-π-D-A dyes (DPP-1 ∼ 4). All dyes have been characterized with NMR, HRMS, UV-vis and fluorescence spectra, and taken into cyclic voltammetry measurements. The devices of new dyes have been determined by photoelectrochemical experiments (IV, IPCE and EIS), in which, solar cell of DPP-4 with biphenyl ring π-spacer enhances obviously its photoelectric conversion efficiency to 7.66% reaching 94% of N719-based standard cell and displays good long-term stability with quasi-solid-state electrolyte. Density functional theory (DFT) calculations of new dyes provide further insight into the molecular geometries and the impacts of the torsion angles on their photovoltaic performance. Large dihedral angles in DPP dyes induce good charge separation for efficient unidirectional flow of electron from donor to acceptor.

  17. Dyeing of Silk with Anthocyanins Dyes Extract from Liriope platyphylla Fruits

    Directory of Open Access Journals (Sweden)

    Huayin Wang

    2014-01-01

    Full Text Available A new source of natural anthocyanins dyes, from Liriope platyphylla fruit, is proposed. This paper analyzes the dye extracts, the primary color components of the extracts, the color features of the extracts under different pH conditions, and their application in silk dyeing. The research shows that, nine anthocyanins are found in  L. platyphylla fruits by analyzing the results of the HPLC/DAD, MS, and MS/MS spectra. The five major anthocyanins related to delphinidin, petunidin, and malvidin derivatives take up 91.72% of total anthocyanin contents. The color of the solution is red under acidic condition (pH < 3.0 and stays in yellow under alkaline condition with pH values above 7.0. The dye extracts applied to silk fabric with mordant free dyeing show different color under different pH conditions, changing between purple, blue, green, and yellow. However, the dyed colors is light and the dyeing rate is low. Metal mordant such as Sn in chelation enhances the dye depth and improves the fastness of the dyed silk fabrics, especially in silk fabrics dyed by premordanting and metamordanting.

  18. In-situ Decolorization of Residual Dye Effluent in Textile Jet Dyeing Machine by Ozone

    Directory of Open Access Journals (Sweden)

    Irfan Ahmed Shaikh

    2014-12-01

    Full Text Available In this study, a new idea of decolourization was investigated in which residual dyeing effluent from textile dyeing process was treated using O3 in the same machine where it was generated. The novelty comes from the idea of doing dyeing and treatment simultaneously. At the completion of dyeing process, O3 gas was injected directly into the machine to remove colour and COD from the wastewater. To evaluate the effectiveness of new method, pilot-scale studies were performed, and decolourization of residual dyeing effluents containing C.I. Reactive Orange 7, C.I. Reactive Blue 19, and C.I. Reactive Black 5 was carried out in specially built textile jet dyeing machine. The results showed that almost 100% colour removal and 90% COD reduction were achieved when process conditions such as pH, dye concentration (mg/L, ozone production rate (g/hr, and temperature were optimized. The study concludes that new method has a great potential to eliminate the need of a separate end-of-the-pipe wastewater treatment system, thus offering an on-site and cost-effective solution.

  19. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy

    Science.gov (United States)

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-07-01

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells.

  20. Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells.

    Science.gov (United States)

    Ananth, S; Vivek, P; Arumanayagam, T; Murugakoothan, P

    2014-07-15

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

  1. Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells

    Science.gov (United States)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2014-07-01

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

  2. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy.

    Science.gov (United States)

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-07-22

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells.

  3. Continuous-wave organic dye lasers and methods

    Science.gov (United States)

    Shapira, Ofer; Chua, Song-Liang; Zhen, Bo; Lee, Jeongwon; Soljacic, Marin

    2014-09-16

    An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuously so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.

  4. The Ideal Solvent for Paper Chromatography of Food Dyes.

    Science.gov (United States)

    Markow, Peter G.

    1988-01-01

    Uses paper chromatography with food dyes to provide a simple and inexpensive basis for teaching chromatography. Provides experimental methodology and tabled results. Includes a solvent system comparison (Rf) for seven dyes and twenty-two solvents. (MVL)

  5. Novel Tunable Dye Laser for Lidar Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A tunable dye laser for Lidar detection will be fabricated based on the innovative dye-doped Holographic Polymer Dispersed Liquid Crystals (HPDLC) technology. The...

  6. Contact dermatitis to hair dye: An update

    Directory of Open Access Journals (Sweden)

    Sanjeev Handa

    2012-01-01

    Full Text Available Exposure to hair dyes has long been known as a significant risk factor for development of allergic contact dermatitis among the exposed population as these lead to severe eczema of face and upper trunk in the consumer and hand eczema in hair-dressers. Currently, para-phenylenediamine (PPD is the main ingredient used in permanent hair color products in the market and is the most important allergen. Prevalence of PPD sensitization is high in patients with contact dermatitis across all continents, with hair dye use being the commonest cause. In order to decrease the burden of disease, use of alternative natural dyeing agents among consumers and use of barrier neoprene gloves among hairdressers should be encouraged apart from stringent legislation to reduce the amount of PPD reaching the consumer.

  7. Calcium supplement: humanity's double-edged sword.

    Science.gov (United States)

    Bunyaratavej, Narong; Buranasinsup, Shutipen

    2011-10-01

    The principle aim of the present study is to investigate the dark side of calcium, pollutions in calcium preparation especially lead (Pb), mercury (Hg) and cadmium (Cd). The collected samples were the different calcium salts in the market and 18 preparations which were classified into 3 groups: Calcium carbonate salts, Chelated calcium and natural-raw calcium. All samples were analyzed for lead, cadmium and mercury by inductively Coupled Plasma Mass Spectrometry (ICP-MS) technique, in house method based on AOAC (2005) 999.10 by ICP-MS. The calcium carbonate and the natural-raw calcium in every sample contained lead at 0.023-0.407 mg/kg of calcium powder. Meanwhile, the natural-raw calcium such as oyster, coral and animal bone showed amount of lead at 0.106-0.384 mg/kg with small amounts of mercury and cadmium. The chelated calcium such as calcium gluconate, calcium lactate and calcium citrate are free of lead.

  8. Effectiveness of dye sensitised solar cell under low light condition using wide band dye

    Energy Technology Data Exchange (ETDEWEB)

    Sahmer, Ahmad Zahrin, E-mail: ahmadzsahmer@gmail.com; Mohamed, Norani Muti, E-mail: noranimuti-mohamed@petronas.com.my; Zaine, Siti Nur Azella, E-mail: ct.azella@gmail.com [Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2015-07-22

    Dye sensistised solar cell (DSC) based on nanocrystalline TiO{sub 2} has the potential to be used in indoor consumer power application. In realizing this, the DSC must be optimized to generate power under low lighting condition and under wider visible light range. The use of wide band dye N749 which has a wider spectrum sensitivity increases the photon conversion to electron between the visible light spectrums of 390nm to 700nm. This paper reports the study on the effectiveness of the dye solar cell with N749 dye under low light condition in generating usable power which can be used for indoor consumer application. The DSC was fabricated using fluorine doped tin oxide (FTO) glass with screen printing method and the deposited TiO{sub 2} film was sintered at 500°C. The TiO{sub 2} coated FTO glass was then soaked in the N749 dye, assembled into test cell, and tested under the standard test condition at irradiance of 1000 W/m{sup 2} with AM1.5 solar soaker. The use of the 43T mesh for the dual pass screen printing TiO{sub 2} paste gives a uniform TiO{sub 2} film layer of 16 µm. The low light condition was simulated using 1/3 filtered irradiance with the solar soaker. The fabricated DSC test cell with the N749 dye was found to have a higher efficiency of 6.491% under low light condition compared to the N719 dye. Under the standard test condition at 1 sun the N749 test cell efficiency is 4.55%. The increases in efficiency is attributed to the wider spectral capture of photon of the DSC with N749 dye. Furthermore, the use of N749 dye is more effective under low light condition as the V{sub OC} decrement is less significant compared to the latter.

  9. Removal of textile dyes with biopolymers xanthan and alginic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lozano-Alvarez, J.; Jauregui-Rincon, J.; Mendoza-Diaz, G.; Rodriguez-Vazquez, G.; Frausto-Reyes, C.

    2009-07-01

    Textile industry is an important activity that provides considerable benefits to people, but unfortunately dyeing of yarn and cloth produces pollution of water, a resource that is valuable and scarce. Dyeing of textiles fibers is an inefficient process, in view of the fact that approximately ten percent of total dye is thrown to municipal sewage. Although different treatment systems are applied to wastewater, dyes are resistant to physical, chemical and biological factors because of the way they are designed. (Author)

  10. 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.

  11. Nucleophilic Addition of Reactive Dyes on Amidoximated Acrylic Fabrics

    OpenAIRE

    2014-01-01

    Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% owf of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophi...

  12. Synthesis, characterization and application of new azo dyes derived from uracil for polyester fibre dyeing

    Science.gov (United States)

    Yazdanbakhsh, Mohamad-reza; Abbasnia, Masoumeh; Sheykhan, Mehdi; Ma'mani, Leila

    2010-08-01

    Some novel uracil derived azo compounds were synthesized by diazotization of substituted aromatic amines, amidine- and guanidine-like amines such as 2-aminopyridine and 2-aminopyrimidine, ortho-hydroxy aniline and ortho-hydroxy naphthyl amines and coupling reaction with 6-amino-1,3-dimethyluracil. Structures of the dyes were fully characterized by spectroscopic techniques (UV, 1H NMR, 13C NMR, CHN and IR). The dyes were applied to polyester, affording orange-yellow shades and the wash fastness of the dyeings was excellent.

  13. 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.

  14. Optofluidic third order distributed feedback dye laser

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2006-01-01

    This letter describes the design and operation of a polymer-based third order distributed feedback (DFB) microfluidic dye laser. The device relies on light confinement in a nanostructured polymer film where an array of nanofluidic channels is filled by capillary action with a liquid dye solution...... which has a refractive index lower than that of the polymer. In combination with a third order DFB grating, formed by the array of nanofluidic channels, this yields a low threshold for lasing. The laser is straightforward to integrate on lab-on-a-chip microsystems where coherent, tunable light...

  15. Preparation of some new coumarin dyes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Series of coumarins containing heterocyclic substituent in 3-position were prepared.Sulfonyl chloride, a reactive group, was drawn into the heterocycle, and further condensed withamines to give series of new compounds that contain N-alkyl sulfamide. The spectral propertiesand dyeing character of these new dyes are discussed. A bathochromic shift (10 nm), enhancedfastness in light and sublimation (1-2 grade) and larger molar extinction coefficient (increase 104L ·mol-1 ·cm-1) are apparent with these new compounds. In the meantime, larger solubility appearswith these new compounds.

  16. Waste Water Treatment of Dye Contamination

    Directory of Open Access Journals (Sweden)

    Pattana Boonyaprapa

    2009-01-01

    Full Text Available The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment systems. Eighty-five percent of tie-dye entrepreneurs agreed that there must be wastewater treatment before release into the environment. From group discussions, it was found that the entrepreneurs realized the wastewater problem and wanted to carry out environment friendly tie-dyeing. Our study demonstrated that the average value of the colour density, chemical oxygen demand (COD, total dissolved solids (TDS and pH of the wastewater characteristics were 170 SU (space units, 1584 mg/l, 2487 mg/l and 8, respectively. For the upflow anaerobic filter, 5 sets of experiments, with 24 hours retention time, were designed, with 0, 1, 2, 3 and 4 % of cow’s feces ferment, respectively (sets 1st-5th. The result showed decreasing colour densities from 170 SU to 160 SU (dark colour, 60 SU (very light colour, 12 SU (no colour, 10 SU (no colour and 10 SU (no colour, respectively. We conclude that the upflow anaerobic filter, containing 2% cow’s feces ferment is an efficient way to reduce colour density of the wastewater. Mixing cow’s feces ferment with tie-dye wastewater increased COD and TDS in wastewater. Mean COD was increased by residual organic matter from 1584 mg/l (before treatment to (after-treatment, sets 2nd- 5th 1600 mg/l, 1680 mg/l, 1710 mg/l and 1750 mg/l, respectively. COD aftertreatment was higher than the industrial effluence standard (400 mg/l. Further treatment COD might include wetland procedures. TDS was increased by some residual organic matter

  17. Erythema multiforme following application of hair dye

    Directory of Open Access Journals (Sweden)

    Sankha Koley

    2012-01-01

    Full Text Available Erythema multiforme (EM is an acute mucocutaneous hypersensitivity reaction with varying degrees of blistering and ulceration. Common causes of EM are herpes simplex virus infection, mycoplasma infection, drug hypersensitivity, vaccination and drug-virus interaction. EM induced by contact dermatitis is rare. Paraphenylene diamine, a common ingredient in many hair dyes, is well known to produce allergic contact dermatitis. We report a 35-year-old lady presenting with EM following severe contact dermatitis to hair dye. So far as we know, this is the first report from India describing EM following contact dermatitis.

  18. Tunability of optofluidic distributed feedback dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2007-01-01

    We investigate the tunability of optofluidic distributed feedback (DFB) dye lasers. The lasers rely on light-confinement in a nano-structured polymer film where an array of nanofluidic channels constitutes a third order Bragg grating DFB laser resonator with a central phase-shift. The lasers...... are operated by filling the DFB laser resonator with a dye solution by capillary action and optical pumping with a frequency doubled Nd: YAG laser. The low reflection order of the DFB laser resonator yields low out-of-plane scattering losses as well as a large free spectral range (FSR), and low threshold...

  19. Functional Dyes, and Some Hi-Tech Applications

    Directory of Open Access Journals (Sweden)

    Reda M. El-Shishtawy

    2009-01-01

    Full Text Available An overview of the recent developments in functional dyes, which are useful for hi-tech applications for those based on optoelectronics, such as dye sensitized solar cells, photochromic dyes and biomedical applications, such as photodynamic therapy for the treatment of cancer and fluorescent sensors is presented.

  20. Integrated sequential anaerobic/aerobic biodegradation of azo dyes

    NARCIS (Netherlands)

    Tan, N.C.G.

    2001-01-01

    Azo dyes constitute a major class of environmental pollutants accounting for 60 to 70% of all dyes and pigments used. These compounds are characterized by aromatic moieties linked together with azo groups (-N=N-). The release of azo dyes into the environment is a concern due to coloration of natural

  1. 21 CFR 864.1850 - Dye and chemical solution stains.

    Science.gov (United States)

    2010-04-01

    ... synthetic or natural dyes or nondye chemicals in solutions used in staining cells and tissues for diagnostic... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dye and chemical solution stains. 864.1850 Section... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and...

  2. Fluorescence of dyes adsorbed on highly organized nanostructured gold surfaces

    NARCIS (Netherlands)

    Levi, Stefano A.; Mourran, Ahmed; Spatz, Joachim P.; Veggel, van Frank C.J.M.; Reinhoudt, David N.; Möller, M.

    2002-01-01

    It is shown that fluorescent dyes can be adsorbed selectively on gold nanoparticles which are immobilized on a glass substrate and that the fluorescence originating from the adsorbed dyes exhibits significantly less quenching when compared to dyes adsorbed on bulk gold. Self-assembled monolayers of

  3. Carboxyfluorescein Diacetate Succinimidyl Ester Fluorescent Dye for Cell Labeling

    Institute of Scientific and Technical Information of China (English)

    Xiao-Qi WANG; Xiu-Mei DUAN; Li-Hua LIU; Yan-Qiu FANG; Yan TAN

    2005-01-01

    Our objective was to study the properties of the carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) and the methodology of cell labeling using CFDA-SE fluorescent dye. First, we analyzed the kinetics of CFDA-SE fluorescent dye intensity over time. Second, we determined the optimal concentration of CFDA-SE fluorescent dye for cell labeling. Third, we tested the toxicity of CFDA-SE fluorescent dye on labeled cells. Finally, we determined the optimal staining time of CFDA-SE fluorescent dye for cell labeling.The results show that the optimal concentration of CFDA-SE fluorescent dye for cell labeling varies according to different cell types. CFDA-SE fluorescent dye is non-toxic to cells as the cell death rate caused by CFDASE labeling is below 5%. The optimal cell labeling time was determined to be 8 min of incubation with CFDA-SE fluorescent dye. We concluded that the advantages of using CFDA-SE fluorescent dye for cell labeling are as follows: (1) the binding of CFDA-SE fluorescent dye to cells is stable; (2) CFDA-SE fluorescent dye is not toxic and does not modify the viability of labeled cells; and (3) CFDA-SE fluorescent dye is a suitable fluorochrome for cell labeling.

  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. The effect of variable calcium and very low calcium diets on human calcium metabolism. Ph.D. Thesis. Final Report

    Science.gov (United States)

    Chu, J.

    1971-01-01

    The effects of a very low calcium diet, with variable high and low protein intake, on the dynamics of calcium metabolism and the mechanism of calciuretics, are examined. The experiment, using male subjects, was designed to study the role of intestinal calcium absorption on urinary calcium excretion, and the rate of production of endogeneously secreted calcium in the gastrointestinal tract. The study showed an average of 70% fractional absorption rate during very low calcium intake, and that a decrease in renal tubular reabsorption of calcium is responsible for calciuretic effects of high protein intake. The study also indicates that there is a tendency to develop osteoporosis after long periods of low calcium intake, especially with a concurrent high protein intake.

  6. Vitamin D and intestinal calcium absorption.

    Science.gov (United States)

    Christakos, Sylvia; Dhawan, Puneet; Porta, Angela; Mady, Leila J; Seth, Tanya

    2011-12-05

    The principal function of vitamin D in calcium homeostasis is to increase calcium absorption from the intestine. Calcium is absorbed by both an active transcellular pathway, which is energy dependent, and by a passive paracellular pathway through tight junctions. 1,25Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) the hormonally active form of vitamin D, through its genomic actions, is the major stimulator of active intestinal calcium absorption which involves calcium influx, translocation of calcium through the interior of the enterocyte and basolateral extrusion of calcium by the intestinal plasma membrane pump. This article reviews recent studies that have challenged the traditional model of vitamin D mediated transcellular calcium absorption and the crucial role of specific calcium transport proteins in intestinal calcium absorption. There is also increasing evidence that 1,25(OH)(2)D(3) can enhance paracellular calcium diffusion. The influence of estrogen, prolactin, glucocorticoids and aging on intestinal calcium absorption and the role of the distal intestine in vitamin D mediated intestinal calcium absorption are also discussed.

  7. Membrane Potential and Calcium Dynamics in Beta Cells from Mouse Pancreas Tissue Slices: Theory, Experimentation, and Analysis.

    Science.gov (United States)

    Dolenšek, Jurij; Špelič, Denis; Klemen, Maša Skelin; Žalik, Borut; Gosak, Marko; Rupnik, Marjan Slak; Stožer, Andraž

    2015-10-28

    Beta cells in the pancreatic islets of Langerhans are precise biological sensors for glucose and play a central role in balancing the organism between catabolic and anabolic needs. A hallmark of the beta cell response to glucose are oscillatory changes of membrane potential that are tightly coupled with oscillatory changes in intracellular calcium concentration which, in turn, elicit oscillations of insulin secretion. Both membrane potential and calcium changes spread from one beta cell to the other in a wave-like manner. In order to assess the properties of the abovementioned responses to physiological and pathological stimuli, the main challenge remains how to effectively measure membrane potential and calcium changes at the same time with high spatial and temporal resolution, and also in as many cells as possible. To date, the most wide-spread approach has employed the electrophysiological patch-clamp method to monitor membrane potential changes. Inherently, this technique has many advantages, such as a direct contact with the cell and a high temporal resolution. However, it allows one to assess information from a single cell only. In some instances, this technique has been used in conjunction with CCD camera-based imaging, offering the opportunity to simultaneously monitor membrane potential and calcium changes, but not in the same cells and not with a reliable cellular or subcellular spatial resolution. Recently, a novel family of highly-sensitive membrane potential reporter dyes in combination with high temporal and spatial confocal calcium imaging allows for simultaneously detecting membrane potential and calcium changes in many cells at a time. Since the signals yielded from both types of reporter dyes are inherently noisy, we have developed complex methods of data denoising that permit for visualization and pixel-wise analysis of signals. Combining the experimental approach of high-resolution imaging with the advanced analysis of noisy data enables novel

  8. Calcium electroporation in three cell lines; a comparison of bleomycin and calcium, calcium compounds, and pulsing conditions

    DEFF Research Database (Denmark)

    Frandsen, Stine Krog; Gissel, Hanne; Hojman, Pernille;

    2013-01-01

    electroporation and electrochemotherapy. METHODS: The effects of calcium electroporation and bleomycin electroporation (alone or in combination) were compared in three different cell lines (DC-3F, transformed Chinese hamster lung fibroblast; K-562, human leukemia; and murine Lewis Lung Carcinoma). Furthermore...... survival at similar applied voltage parameters. The effect of calcium electroporation is independent of calcium compound. GENERAL SIGNIFICANCE: This study strongly supports the use of calcium electroporation as a potential cancer therapy and the results may aid in future clinical trials....

  9. A model for recombination in Type II dye-sensitized solar cells: Catechol-thiophene dyes

    Science.gov (United States)

    Manzhos, Sergei; Segawa, Hiroshi; Yamashita, Koichi

    2011-03-01

    Recombination in dye-sensitized solar cells with direct injection is cast as internal conversion in the dye-Ti(OH) 2 complex. For catechol-thiophene dyes with 1, 2, or 3 thiophene units, the complex reproduces the previously observed dye-to-semiconductor bands. We compare the decomposition of the internal conversion rate by vibrational mode and predict a trend in recombination with the extension of conjugation, which offers an explanation for the trend in DSSC efficiency. We employ a simple model for the vibrational factors and show that they are only important in the presence of vibrational modes with ℏω⩽kT and strong electronic factors, as is the case here.

  10. Dye-sensitized solar cells with natural dyes extracted from plant seeds

    Science.gov (United States)

    El-Ghamri, Hatem S.; El-Agez, Taher M.; Taya, Sofyan A.; Abdel-Latif, Monzir S.; Batniji, Amal Y.

    2014-12-01

    The application of natural dyes extracted from plant seeds in the fabrication of dye-sensitized solar cells (DSSCs) has been explored. Ten dyes were extracted from different plant seeds and used as sensitizers for DSSCs. The dyes were characterized using UV-Vis spectrophotometry. DSSCs were prepared using TiO2 and ZnO nanostructured mesoporous films. The highest conversion efficiency of 0.875 % was obtained with an allium cepa (onion) extract-sensitized TiO2 solar cell. The process of TiO2-film sintering was studied and it was found that the sintering procedure significantly affects the response of the cell. The short circuit current of the DSSC was found to be considerably enhanced when the TiO2 semiconducting layer was sintered gradually.

  11. Dye linked conjugated homopolymers: using conjugated polymer electroluminescence to optically pump porphyrin-dye emission

    DEFF Research Database (Denmark)

    Nielsen, K.T.; Spanggaard, H.; Krebs, Frederik C

    2004-01-01

    . Electroluminescent devices of the homopolymer itself and of the zinc-porphyrin containing polymer were prepared and the nature of the electroluminescence was characterized. The homopolymer segments were found to optically pump the emission of the zinc-porphyrin dye moities. The homopolymer exhibits blue......Zinc-porphyrin dye molecules were incorporated into the backbone of a conjugated polymer material by a method, which allowed for the incorporation of only one zinc-porphyrin dye molecule into the backbone of each conjugated polymer molecule. The electronic properties of the homopolymer were......-green emission and the zinc-porphyrin linked homopolymers emit near-infrared/infrared light. This was demonstrated to be due to electroluminescence pumping of the zinc-porphyrin moieties that were covalently linked to homopolymer material. When only one zinc-porphyrin dye was incorporated into the backbone...

  12. Dye-sensitized solar cells with natural dyes extracted from achiote seeds

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ortiz, N.M.; Vazquez-Maldonado, I.A.; Azamar-Barrios, J.A.; Oskam, G. [Departamento de Fisica Aplicada, CINVESTAV-IPN, Merida, Yuc. 97310 (Mexico); Perez-Espadas, A.R.; Mena-Rejon, G.J. [Laboratorio de Quimica Organica de Investigacion, Facultad de Quimica, Universidad Autonoma de Yucatan, Merida, Yuc. 97150 (Mexico)

    2010-01-15

    We have explored the application of natural dyes extracted from the seeds of the achiote shrub (Bixa orellana L.) in dye-sensitized solar cells (DSCs). The main pigments are bixin and norbixin, which were obtained by separation and purification from the dark-red extract (annatto). The dyes were characterized using {sup 1}H-NMR, FTIR spectroscopy, and UV-Vis spectrophotometry. Solar cells were prepared using TiO{sub 2} and ZnO nanostructured, mesoporous films and the annatto, bixin, and norbixin as sensitizers. The best results were obtained with bixin-sensitized TiO{sub 2} solar cells with efficiencies of up to 0.53%, illustrating the importance of purification of dyes from natural extracts. (author)

  13. Investigation on Effluent Characteristics of Organic Cotton Fabric Dyeing With Eco-Friendly Remazol Reactive Dyes

    OpenAIRE

    Md. Mashiur Rahman Khan; Md. Mazedul Islam; Elias Khalil

    2014-01-01

    Environmental sustainability is the major concern in the age of modern world. For textile and apparel sector, this has been a burning issue for many related concerned bodies. The pretreatment and dyeing process of greige fabrics results in large volume of effluents that has harmful effect on environment. In this study, the ecological parameters of the effluents obtained from scouring and dyeing of 100% organic cotton single jersey knitted fabrics with environmentally low impact Remazol ser...

  14. Dye-sensitized solar cells based on dyes extracted from dried plant leaves

    OpenAIRE

    Sofyan A. Taya; Taher M. El-Agez; ELREFI, Kamal S.

    2015-01-01

    In this work, natural dyes were extracted from dried plant leaves of plant cream, apricot, figs, apples, sage, thyme, mint, Ziziphus jujuba, orange, shade tree, basil, berry, Mirabelle plum, Victoria plum, peach, mango, pomegranate, banana, guava, and fluoridation-treated plant. The extracts were used as photosensitizers for dye-sensitized solar cells (DSSCs). The cells were assembled using nanostructured TiO2 films. The best performance was observed for the DSSC sensitized with Ziziphus juju...

  15. Dye-sensitized solar cell using natural dyes extracted from spinach and ipomoea

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H., E-mail: f10381@ntut.edu.t [Department of Mechanical Engineering, National Taipei University of Technology, No. 1. Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Wu, H.M. [Department of Materials Engineering, Tatung University, No. 40, Sec. 3, Jhongshan N. Rd. Jhongshan District, Taipei City 104, Taiwan (China); Chen, T.L. [Department of Industrial Design, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Huang, K.D. [Department of Vehicle Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Jwo, C.S. [Department of Energy and Air-Conditioning Refrigeration Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Lo, Y.J. [Department of Mechanical Engineering, National Taipei University of Technology, No. 1. Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China)

    2010-04-16

    This study used spinach extract, ipomoea leaf extract and their mixed extracts as the natural dyes for a dye-sensitized solar cell (DSSC). Spinach and ipomoea leaves were first placed separately in ethanol and the chlorophyll of these two kinds of plants was extracted to serve as the natural dyes for using in DSSCs. In addition, the self-developed nanofluid synthesis system prepared a TiO{sub 2} nanofluid with an average particle size of 50 nm. Electrophoresis deposition was performed to let the TiO{sub 2} deposit nanoparticles on the indium tin oxide (ITO) conductive glass, forming a TiO{sub 2} thin film with the thickness of 11.61 {mu}m. This TiO{sub 2} thin film underwent sintering at 450 {sup o}C to enhance the compactness of thin film. Finally, the sintered TiO{sub 2} thin film was immersed in the natural dye solutions extracted from spinach and ipomoea leaves, completing the production of the anode of DSSC. This study then further inspected the fill factor, photoelectric conversion efficiency and incident photon current efficiency of the encapsulated DSSC. According to the experimental results of current-voltage curve, the photoelectric conversion efficiency of the DSSCs prepared by natural dyes from ipomoea leaf extract is 0.318% under extraction temperature of 50 {sup o}C and pH value of extraction fluid at 1.0. This paper also investigated the influence of the temperature in the extraction process of this kind of natural dye and the influence of pH value of the dye solution on the UV-VIS patterns absorption spectra of the prepared natural dye solutions, and the influence of these two factors on the photoelectric conversion efficiency of DSSC.

  16. The effect of calcium gluconate and other calcium supplements as a dietary calcium source on magnesium absorption in rats.

    Science.gov (United States)

    Chonan, O; Takahashi, R; Yasui, H; Watanuki, M

    1997-01-01

    The effects of commercially available calcium supplements (calcium carbonate, calcium gluconate, oyster shell preparation and bovine bone preparation) and gluconic acid on the absorption of calcium and magnesium were evaluated for 30 days in male Wistar rats. There were no differences in the apparent absorption ratio of calcium among rats fed each calcium supplement; however, the rats fed the calcium gluconate diet had a higher apparent absorption ratio of magnesium than the rats fed the other calcium supplements. Dietary gluconic acid also more markedly stimulated magnesium absorption than the calcium carbonate diet, and the bone (femur and tibia) magnesium contents of rats fed the gluconic acid diet were significantly higher than those of the rats fed the calcium carbonate diet. Furthermore, the weight of cecal tissue and the concentrations of acetic acid and butyric acid in cecal digesta of rats fed the calcium gluconate diet or the gluconic acid diet were significantly increased. We speculate that the stimulation of magnesium absorption in rats fed the calcium gluconate diet is a result of the gluconic acid component and the effect of gluconic acid on magnesium absorption probably results from cecal hypertrophy, magnesium solubility in the large intestine and the effects of volatile fatty acids on magnesium absorption.

  17. Stimulus-evoked calcium transients in somatosensory cortex are temporarily inhibited by a nearby microhemorrhage.

    Directory of Open Access Journals (Sweden)

    Flor A Cianchetti

    Full Text Available Although microhemorrhages are common in the brain of the elderly, the direct impact of these lesions on neural function remains unclear. In this work, we used femtosecond laser irradiation to rupture the wall of single arterioles in the brain of anesthetized rodents, producing a hematoma of ∼100-µm diameter. Our objective was to study the impact of these microhemorrhages on cortical activity using cell-resolved two-photon imaging of bulk-loaded calcium-sensitive dye. We monitored peripheral sensory stimulus-induced calcium transients from individual neuronal cell bodies, regions of neuropil, and astrocytes at different distances from the microhemorrhage before and 0.5, 2, and 4 hours after the creation of the lesion. We found that immediately after the hemorrhage the average amplitude of the stimulus-induced calcium response was reduced to about half within 150 µm from the hematoma. Beyond 300 µm, there was little effect on cell response, with a smooth increase in response amplitude from 150 µm to 300 µm from the lesion. Cortical function gradually improved with time and by four hours after the lesion the response from neurons and astrocytes had recovered to baseline everywhere but within 150 µm from the hematoma. To assess whether the cells closest to the microhemorrhage recovered over a longer timeframe, we developed a re-openable chronic cranial window preparation that allowed reinjection of calcium-sensitive fluorescent dye. We found that the response largely recovered by one day after the microhemorrhage even within 150 µm from the hematoma. This work suggests that neuronal and astrocyte function is transiently lost near a microhemorrhage, but recovers within one day after the lesion.

  18. Degradation of various dyes using Laccase enzyme.

    Science.gov (United States)

    Dhaarani, S; Priya, A K; Rajan, T Vel; Kartic, D Navamani

    2012-10-01

    Disposal of untreated dyeing effluent in water bodies, from textile industries, cause serious environmental and health hazards. The chemical structures of dye molecules are designed to resist fading on exposure to light or chemical attack, and they prove to be quite resistant towards microbial degradation. Therefore, current conventional biological processes may not be able to meet wastewater discharge criteria and reuse. An enzymatic treatment undergoes oxidative cleavage avoiding formation of toxic amines. Laccase is a multi-copper containing protein that catalyzes the oxidation of a wide range of aromatic substrates concomitantly with the reduction of molecular oxygen to water. UV visible spectral analysis of various synthetic dyes was performed in the study and wavelengths of maximum absorbance determined. Laccase enzyme was obtained from the fungi Pleorotus ostreatus. The enzyme showed high efficiency against Malachite Green, Basic Red and Acid Majanta with decolorization capacities of 97%, 94% and 94% respectively. Further, these dyes can be used for optimization of degradation parameters and analysis of degradation products.

  19. Optofluidic dye laser in a foil

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Christiansen, Mads Brøkner; Mappes, Timo;

    2010-01-01

    First order distributed feedback optofluidic dye lasers embedded in a 350 mu m thick TOPAS (R) foil are demonstrated. They are designed in order to give high output pulse energies. Microfluidic channels and first order distributed feedback gratings are fabricated in parallel by thermal nanoimprin...

  20. Removal of triphenylmethane dyes by bacterial consortium.

    Science.gov (United States)

    Cheriaa, Jihane; Khaireddine, Monia; Rouabhia, Mahmoud; Bakhrouf, Amina

    2012-01-01

    A new consortium of four bacterial isolates (Agrobacterium radiobacter; Bacillus spp.; Sphingomonas paucimobilis, and Aeromonas hydrophila)-(CM-4) was used to degrade and to decolorize triphenylmethane dyes. All bacteria were isolated from activated sludge extracted from a wastewater treatment station of a dyeing industry plant. Individual bacterial isolates exhibited a remarkable color-removal capability against crystal violet (50 mg/L) and malachite green (50 mg/L) dyes within 24 h. Interestingly, the microbial consortium CM-4 shows a high decolorizing percentage for crystal violet and malachite green, respectively, 91% and 99% within 2 h. The rate of chemical oxygen demand (COD) removal increases after 24 h, reaching 61.5% and 84.2% for crystal violet and malachite green, respectively. UV-Visible absorption spectra, FTIR analysis and the inspection of bacterial cells growth indicated that color removal by the CM-4 was due to biodegradation. Evaluation of mutagenicity by using Salmonella typhimurium test strains, TA98 and TA100 studies revealed that the degradation of crystal violet and malachite green by CM-4 did not lead to mutagenic products. Altogether, these results demonstrated the usefulness of the bacterial consortium in the treatment of the textile dyes.

  1. Expeditious, mechanochemical synthesis of BODIPY dyes

    Directory of Open Access Journals (Sweden)

    Laramie P. Jameson

    2013-04-01

    Full Text Available BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

  2. Novel Fluorescent Dyes Based on Coumarin System

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Seven novel fluorescent coumarin derivatives were synthesized from 7-diethylamino-4-chloro-3-formyl coumarin. The spectra of absorption, excitation and emission were dependent not only on the structures and also on the concentration of dyes. The PPP-MO predictions can only be consistent with the spectra in dilute solutions.

  3. Photochromic dye-sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Noah M. Johnson

    2015-11-01

    Full Text Available We report the fabrication and characterization of photochromic dye sensitized solar cells that possess the ability to change color depending on external lighting conditions. This device can be used as a “smart” window shade that tints, collects the sun's energy, and blocks sunlight when the sun shines, and is completely transparent at night.

  4. Removal of Triphenylmethane Dyes by Bacterial Consortium

    Directory of Open Access Journals (Sweden)

    Jihane Cheriaa

    2012-01-01

    Full Text Available A new consortium of four bacterial isolates (Agrobacterium radiobacter; Bacillus spp.; Sphingomonas paucimobilis, and Aeromonas hydrophila-(CM-4 was used to degrade and to decolorize triphenylmethane dyes. All bacteria were isolated from activated sludge extracted from a wastewater treatment station of a dyeing industry plant. Individual bacterial isolates exhibited a remarkable color-removal capability against crystal violet (50 mg/L and malachite green (50 mg/L dyes within 24 h. Interestingly, the microbial consortium CM-4 shows a high decolorizing percentage for crystal violet and malachite green, respectively, 91% and 99% within 2 h. The rate of chemical oxygen demand (COD removal increases after 24 h, reaching 61.5% and 84.2% for crystal violet and malachite green, respectively. UV-Visible absorption spectra, FTIR analysis and the inspection of bacterial cells growth indicated that color removal by the CM-4 was due to biodegradation. Evaluation of mutagenicity by using Salmonella typhimurium test strains, TA98 and TA100 studies revealed that the degradation of crystal violet and malachite green by CM-4 did not lead to mutagenic products. Altogether, these results demonstrated the usefulness of the bacterial consortium in the treatment of the textile dyes.

  5. Dyeing and Printing Sector Develops Steadily

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ With the rapid growth of the economy,the dyeing and printing sector in China developed considerably in 2006. Highlights of the year include a rapid increase of output levels, considerable growth of profits, a reduction of imports and an expansion of exports.

  6. Mechanism of store-operated calcium entry

    Indian Academy of Sciences (India)

    Devkanya Dutta

    2000-12-01

    Activation of receptors coupled to the phospholipase C/IP3 signalling pathway results in a rapid release of calcium from its intracellular stores, eventually leading to depletion of these stores. Calcium store depletion triggers an influx of extracellular calcium across the plasma membrane, a mechanism known as the store-operated calcium entry or capacitative calcium entry. Capacitative calcium current plays a key role in replenishing calcium stores and activating various physiological processes. Despite considerable efforts, very little is known about the molecular nature of the capacitative channel and the signalling pathway that activates it. This review summarizes our current knowledge about store operated calcium entry and suggests possible hypotheses for its mode of activation.

  7. The ins and outs of mitochondrial calcium.

    Science.gov (United States)

    Finkel, Toren; Menazza, Sara; Holmström, Kira M; Parks, Randi J; Liu, Julia; Sun, Junhui; Liu, Jie; Pan, Xin; Murphy, Elizabeth

    2015-05-22

    Calcium is thought to play an important role in regulating mitochondrial function. Evidence suggests that an increase in mitochondrial calcium can augment ATP production by altering the activity of calcium-sensitive mitochondrial matrix enzymes. In contrast, the entry of large amounts of mitochondrial calcium in the setting of ischemia-reperfusion injury is thought to be a critical event in triggering cellular necrosis. For many decades, the details of how calcium entered the mitochondria remained a biological mystery. In the past few years, significant progress has been made in identifying the molecular components of the mitochondrial calcium uniporter complex. Here, we review how calcium enters and leaves the mitochondria, the growing insight into the topology, stoichiometry and function of the uniporter complex, and the early lessons learned from some initial mouse models that genetically perturb mitochondrial calcium homeostasis.

  8. Familial hypocalciuric hypercalcemia and calcium sensing receptor

    DEFF Research Database (Denmark)

    Mrgan, Monija; Nielsen, Sanne; Brixen, Kim

    2014-01-01

    Familial hypocalciuric hypercalcemia (FHH) is a lifelong, benign autosomal dominant disease characterized by hypercalcemia, normal to increased parathyroid hormone level, and a relatively low renal calcium excretion. Inactivation of the calcium-sensing receptor in heterozygous patients results in...

  9. Decalcification of calcium polycarbophil in rats.

    Science.gov (United States)

    Yamada, T; Saito, T; Takahara, E; Nagata, O; Tamai, I; Tsuji, A

    1997-03-01

    The in vivo decalcification of calcium polycarbophil was examined. The decalcification ratio of [45Ca]calcium polycarbophil in the stomach after oral dosing to rats was more than 70% at each designated time and quite closely followed in the in vitro decalcification curve, indicating that the greater part of the calcium ion is released from calcium polycarbophil under normal gastric acidic conditions. The residual radioactivity in rat gastrointestine was nearly equal to that after oral administration of either [45Ca]calcium chloride + polycarbophil. The serum level of radioactivity was nearly equal to that after oral dosing of [45Ca]calcium lactate. These results indicate that the greater part of orally administered calcium polycarbophil released calcium ions to produce polycarbophil in vivo.

  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. Controlled-release Properties of Microencapsulated Disperse Dyes

    Institute of Scientific and Technical Information of China (English)

    LUO Yan; LI Chun-yan; CHEN Shui-lin

    2002-01-01

    Some disperse dyes were microencapsulated by means of in- situ polymerization. These microencapsulated disperse dyes was extracted respectively by ethanol under certain conditions. The controlled-release properties of disperse dyes through the shell of microcapsules were measured by spectrophotometer. According to the results, it was drawn that the type of disperse dyes, the auxiliaries contained in disperse dyes, the quantity of system controlling medium used and the core/shell ratio of microcapsules play important roles in controlling the release properties of microcapsules. The different controlled- release properties of microcapsules, which were prepared under given conditions, however, would in turn influence the performance of microcapsules in multiple-transfer printing.

  12. Organic dyes based on fluorene and its derivatives

    Science.gov (United States)

    Kurdyukova, I. V.; Ishchenko, Aleksandr A.

    2012-03-01

    Data on various types of organic dyes based on fluorene and its derivatives, including polymethine, styryl, triphenylmethane, spiran, merocyanine, porphyrin and polymeric dyes, as well as azo dyes and donor-acceptor polyenes, are described systematically. The key methods for their synthesis are considered. The properties of the dyes are analyzed and summarized. The principles of development of modern functional materials based on these dyes are outlined. The use of these materials in advanced fields of science and technology such as photovoltaics, electroluminescence, nonlinear optics, holography, sensing photodynamic therapy are considered. The bibliography includes 476 references.

  13. Quantum Efficiency of Fluorescent Dyes and Color Matching

    Institute of Scientific and Technical Information of China (English)

    LI Rong; CHEN Dong-hui

    2002-01-01

    Because of the special optical characters, the color matching of fluorescent dyes is quite complicated. In order to find the algorithm of the color matching of fluorescent dyes, some experiments and measurements of one kind of fluorescent dye were carried out. An elementary probe into the method of color matching of fluorescent dyes has been made through the expression deduced by James S. Bonham and standard KubelkaMunk theory. The results prove that the method has a great applicability for the color matching of fabric dyed with only one kind of fluorescent dye.

  14. The Influence of Hydrophobicity Factor on Wool Fibre Dyeing With Anionic Dye

    Directory of Open Access Journals (Sweden)

    Rasa TREIGIENĖ

    2011-09-01

    Full Text Available In this study two alkylphenolethoxylates with different ethoxylation degree c.a. EO 9 (Lanasan LT as NPE-1 and EO 40 (Disponil AA P43 as NPE-2 were selected with the purpose to evaluate the influence of hydrophobicity of nonionic surfactants on wool dyeing efficiency. Anionic C.I. Acid Orange 7 dye was used to carry out an experiment in dyeing of wool fibre at 30 °C or 60 °C temperature using wool fabric which was prepared for dyeing by extraction of the lipid materials soluble in chloroform and methanol mixture. The surfactant with a shorter hydrophilic chain (NPE-1 intensified the adsorption of the dye. This fact allowed to presume that the dye diffusion into wool fibre might be influenced by hydrophobic interaction between the surfactant and hydrophobic sites of wool fibre. The results of surfactants adsorption showed that the interaction of NPE-2 with the fibre was weak as compared to that of NPE-1. The results of the investigation suggest that the ethoxylated nonylphenol of a lower hydrophility index might interact with the active sites of wool fibre more intensively than that of a higher index of hydrophility.http://dx.doi.org/10.5755/j01.ms.17.3.596

  15. Triphenylamine based organic dyes for dye sensitized solar cells: A theoretical approach

    Science.gov (United States)

    Mohankumar, V.; Pandian, Muthu Senthil; Ramasamy, P.

    2016-05-01

    The geometry, electronic structure and absorption spectra for newly designed triphenylamine based organic dyes were investigated by density functional theory (DFT) and time dependent density functional theory (TD-DFT) with the Becke 3-Parameter-Lee-Yang-parr(B3LYP) functional, where the 6-31G(d,p) basis set was employed. All calculations were performed using the Gaussian 09 software package. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecule. Ultraviolet-visible (UV-vis) spectrum was simulated by TD-DFT in gas phase. The calculation shows that all of the dyes can potentially be good sensitizers for DSSC. The LUMOs are just above the conduction band of TiO2 and their HOMOs are under the reduction potential energy of the electrolytes (I-/I3-) which can facilitate electron transfer from the excited dye to TiO2 and charge regeneration process after photo oxidation respectively. The simulated absorption spectrum of dyes match with solar spectrum. Frontier molecular orbital results show that among all the three dyes, the "dye 3" can be used as potential sensitizer for DSSC.

  16. Mediator-assisted decolorization and detoxification of textile dyes/dye mixture by Cyathus bulleri laccase.

    Science.gov (United States)

    Chhabra, Meenu; Mishra, Saroj; Sreekrishnan, T R

    2008-12-01

    Laccase from basidiomycete fungus Cyathus bulleri was evaluated for its ability to decolorize a number of reactive and acidic dyes in the presence of natural and synthetic mediators. The extent of decolorization was monitored at different mediator/dye concentrations and incubation time. Among the synthetic mediators, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) was effective at low mediator/dye ratios and resulted in 80-95% decolorization at rates that varied from 226 +/- 4 nmol min(-1) mg(-1) for Reactive Orange 1 to 1,333 +/- 15 nmol min(-1) mg(-1) for Reactive Red 198. Other synthetic mediators like 1-hydroxybenzotriazole and violuric acid showed both concentration- and time-dependent increases in percent decolorization. Natural mediators like vanillin, on the other hand, were found to be less effective on all the dyes except Reactive Orange 1. Computed rates of decolorization were about twofold lower than that with ABTS. The laccase-ABTS system also led to nearly 80% decolorization for the simulated dye mixture. No clear correlation between laccase activity on the mediator and its ability to decolorize dyes was found, but pH had a significant effect: Optimum pH for decolorization coincided with the optimum pH for mediator oxidation. The treated samples were also evaluated for toxicity in model microbial systems. The laccase-mediator system appears promising for treatment of textile wastewaters.

  17. Decolorization and biodegradation of reactive dyes and dye wastewater by a developed bacterial consortium.

    Science.gov (United States)

    Saratale, R G; Saratale, G D; Chang, J S; Govindwar, S P

    2010-11-01

    A bacterial consortium (consortium GR) consisting of Proteus vulgaris NCIM-2027 and Micrococcus glutamicus NCIM-2168 could rapidly decolorize and degrade commonly-used sulfonated reactive dye Green HE4BD and many other reactive dyes. Consortium GR shows markedly higher decolorization activity than that of the individual strains. The preferable physicochemical parameters were identified to achieve higher dye degradation and decolorization efficiency. The supplementation of cheap co-substrates (e.g., extracts of agricultural wastes) could enhance the decolorization performance of consortium GR. Extent of mineralization was determined with TOC and COD measurements, showing nearly complete mineralization of Green HE4BD by consortium GR (up to 90% TOC and COD reduction) within 24 h. Oxidoreductive enzymes seemed to be involved in fast decolorization/degradation process with the evidence of enzymes induction in the bacterial consortium. Phytotoxicity and microbial toxicity studies confirm that the biodegraded products of Green HE4BD by consortium GR are non-toxic. Consortium GR also shows significant biodegradation and decolorization activities for mixture of reactive dyes as well as the effluent from actual dye manufacturing industry. This confers the possibility of applying consortium GR for the treatment of industrial wastewaters containing dye pollutants.

  18. Improving the Spectral Response of Black Dye by Cosensitization with a Simple Indoline Based Dye in Dye-Sensitized Solar Cell

    Directory of Open Access Journals (Sweden)

    Md. Akhtaruzzaman

    2013-01-01

    Full Text Available Indoline dye D-1 was successfully applied as a cosensitizer for improving the spectral response of black dye in dye-sensitized solar cells (DSCs. It was observed that D-1 effectively increases the short-circuit photocurrent by offsetting the competitive light absorption by I/I3- electrolyte in the wavelength region 350–500 nm when adsorbed on the TiO2 nanocrystaline films in a mix dye system. The DSCs containing the D-1 and black dye achieved a power conversion efficiency of 9.80% with higher short-circuit photocurrent of 19.54 mA/cm2 compared to the system of black dye without cosensitization under standard AM 1.5 sunlight.

  19. Calcium channel blockers and Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    Yi Tan; Yulin Deng; Hong Qing

    2012-01-01

    Alzheimer's disease is characterized by two pathological hallmarks: amyloid plaques and neurofi-brillary tangles. In addition, calcium homeostasis is disrupted in the course of human aging. Recent research shows that dense plaques can cause functional alteration of calcium signals in mice with Alzheimer's disease. Calcium channel blockers are effective therapeutics for treating Alzheimer's disease. This review provides an overview of the current research of calcium channel blockers in-volved in Alzheimer's disease therapy.

  20. Variable efficacy of calcium carbonate tablets.

    Science.gov (United States)

    Kobrin, S M; Goldstein, S J; Shangraw, R F; Raja, R M

    1989-12-01

    Orally administered calcium carbonate tablets are commonly prescribed as a calcium supplement and for their phosphate-binding effects in renal failure patients. Two cases are reported in which a commercially available brand of calcium carbonate tablets appeared to be ineffective. Formal investigation of the bioavailability of this product revealed it to have impaired disintegration and dissolution and a lack of clinical efficacy. Recommendations that will enable physicians to avoid prescribing and pharmacists to avoid dispensing ineffective calcium carbonate tablets are proposed.

  1. Calcium regulation in endosymbiotic organelles of plants

    OpenAIRE

    Bussemer, Johanna; Vothknecht, Ute C.; Chigri, Fatima

    2009-01-01

    In plant cells calcium-dependent signaling pathways are involved in a large array of biological processes in response to hormones, biotic/abiotic stress signals and a variety of developmental cues. This is generally achieved through binding of calcium to diverse calcium-sensing proteins, which subsequently control downstream events by activating or inhibiting biochemical reactions. Regulation by calcium is considered as a eukaryotic trait and has not been described for prokaryotes. Neverthele...

  2. Teaching Calcium-Induced Calcium Release in Cardiomyocytes Using a Classic Paper by Fabiato

    Science.gov (United States)

    Liang, Willmann

    2008-01-01

    This teaching paper utilizes the materials presented by Dr. Fabiato in his review article entitled "Calcium-induced release of calcium from the cardiac sarcoplasmic reticulum." In the review, supporting evidence of calcium-induced calcium release (CICR) is presented. Data concerning potential objections to the CICR theory are discussed as well. In…

  3. Photodegradation in multiple-dye luminescent solar concentrators

    Energy Technology Data Exchange (ETDEWEB)

    Mooney, Alex M.; Warner, Kathryn E. [School of Science, Pennsylvania State University: Erie, The Behrend College, 4205 College Drive, Erie, PA 16563-0203 (United States); Fontecchio, Paul J. [School of Engineering, Pennsylvania State University: Erie, The Behrend College, 5101 Jordan Road, Erie, PA 16563-1701 (United States); Zhang, Yu-Zhong [Life Technologies Corp., 29851 Willow Creek Road, Eugene, OR 97402 (United States); Wittmershaus, Bruce P., E-mail: bpw2@psu.edu [School of Science, Pennsylvania State University: Erie, The Behrend College, 4205 College Drive, Erie, PA 16563-0203 (United States)

    2013-11-15

    Combining multiple organic dyes to form a fluorescence resonance energy transfer (FRET) network is a useful strategy for extending the spectral range of sunlight absorbed by a luminescent solar concentrator (LSC). Excitation transfer out of the higher energy level dyes in the transfer series competes effectively with their photodegradation rates. Improvements in photostability up to a factor of 18 are observed for the first dye in the FRET series. FRET networks are shown to be a viable means of decreasing the rate of photodegradation of organic dyes used in LSCs. This comes at the expense of the final dye in the network; the depository of most of the excitations created by absorbing sunlight. The photostability and performance of an efficient FRET LSC rest heavily on the photostability and fluorescence quantum yield of the final dye. -- Highlights: • Photodegradation kinetics of multiple-dye FRET LSCs are reported. • The FRET network decreased the first dye's photodegradation rate by a factor of 18. • The final dye in the FRET LSC protects other dyes at its own expense. • The final dye must have excellent photostability and fluorescence quantum yield.

  4. Decolorization of textile dyes by Alishewanella sp. KMK6.

    Science.gov (United States)

    Kolekar, Yogesh M; Kodam, Kisan M

    2012-07-01

    Alishewanella sp. strain KMK6 was isolated from textile dye-contaminated soil. The strain was able to decolorize and degrade different azo dyes and displayed high dye degradation ability and tolerance. The bacterium could completely degrade 2.5 g l(-1) dye, Reactive Blue 59 within 6 h. The induction in the level of cytochrome P-450 and activities of azoreductase and NADH-dichlorophenolindophenol reductase were observed in the cells after dye decolorization indicating the role of these enzymes. The intermediates of Reactive Blue 59 degradation were identified by high-performance liquid chromatography, gas chromatography and mass spectroscopy, and Fourier transform infrared spectroscopy. The ecotoxicity has been evaluated for dye and its metabolites by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (a yellow tetrazole) and comet assay, and it revealed that the dye degradation products were nontoxic.

  5. Halogen Bonding Promotes Higher Dye-Sensitized Solar Cell Photovoltages.

    Science.gov (United States)

    Simon, Sarah J C; Parlane, Fraser G L; Swords, Wesley B; Kellett, Cameron W; Du, Chuan; Lam, Brian; Dean, Rebecca K; Hu, Ke; Meyer, Gerald J; Berlinguette, Curtis P

    2016-08-24

    We report here an enhancement in photovoltage for dye-sensitized solar cells (DSSCs) where halogen-bonding interactions exist between a nucleophilic electrolyte species (I(-)) and a photo-oxidized dye immobilized on a TiO2 surface. The triarylamine-based dyes under investigation showed larger rate constants for dye regeneration (kreg) by the nucleophilic electrolyte species when heavier halogen substituents were positioned on the dye. The open-circuit voltages (VOC) tracked these kreg values. This analysis of a homologous series of dyes that differ only in the identity of two halogen substituents provides compelling evidence that the DSSC photovoltage is sensitive to kreg. This study also provides the first direct evidence that halogen-bonding interactions between the dye and the electrolyte can bolster DSSC performance.

  6. Novel method for evaluation of natural dyes in DSSC

    Energy Technology Data Exchange (ETDEWEB)

    Lakshmi, M.; Kavitha, S. [Department of Physics, Mercy College, Calicut University, Palakkad, 687006, Kerala (India); Paul, Mercyleena [Department of Chemistry, Mercy College, Calicut University, Palakkad, 687006, Kerala (India)

    2014-10-15

    Dye sensitized Solar Cell (DSSC) is presently centered on Ruthenium based dyes. Recent research is diverted to explore the potential of natural dyes in replacing the conventional dyes. In this work we have chosen few natural dyes, which when coated on TiO{sub 2} leads to increase in absorption capacity of TiO{sub 2}. Co-relation of absorption and electrochemical properties of natural dyes gives a scientific insight of the probable performance of a dye, even without fabricating a cell. We have tried to compare this predictions based on HOMO-LUMO energy levels with the real cell performance. Measurements of cell parameters suggest that there is scope for further research in this area.

  7. 21 CFR 582.5217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium phosphate. 582.5217 Section 582.5217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  8. 21 CFR 582.1217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium phosphate. 582.1217 Section 582.1217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  9. 21 CFR 182.1217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium phosphate. 182.1217 Section 182.1217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  10. Abnormalities of serum calcium and magnesium

    Science.gov (United States)

    Neonatal hypocalcemia is defined as a total serum calcium concentration of <7 mg/dL or an ionized calcium concentration of <4 mg/dL (1mmol/L). In very low birth weight (VLBW) infants, ionized calcium values of 0.8 to 1 mmol/L are common and not usually associated with clinical symptoms. In larger in...

  11. Acute calcium homeostasis in MHS swine.

    Science.gov (United States)

    Harrison, G G; Morrell, D F; Brain, V; Jaros, G G

    1987-07-01

    To elucidate a pathogenesis for the reduction in bone calcium content observed in MHS individuals, we studied the acute calcium homeostasis of MHS swine. This was achieved by the serial measurement, with a calcium selective electrode, of calcium transients in Landrace MHS (five) and control Landrace/large white cross MH negative (five) swine following IV bolus injection of calcium gluconate 0.1 mmol X kg-1--a dose which induced an acute 45 per cent increase in plasma ionised calcium. Experimental animals were anaesthetised with ketamine 10 mg X kg-1 IM, thiopentone (intermittent divided doses) 15-25 mg X kg-1 (total) IV and N2O/O2 (FIO2 0.3) by IPPV to maintain a normal blood gas, acid/base state. The plasma ionised calcium decay curve observed in MHS swine did not differ from that of control normal swine. Further it was noted that the induced acute rise in plasma ionised calcium failed to trigger the MH syndrome in any MHS swine. It is concluded that the mechanisms of acute calcium homeostasis in MHS swine are normal. An explanation for the reduction in bone calcium content observed in MHS individuals must be sought, therefore, through study of the slow long-term component of the calcium regulatory process. In addition, the conventional strictures placed on the use, in MHS patients, of calcium gluconate are called in question.

  12. Multifaceted Role of Calcium in Cancer.

    Science.gov (United States)

    Sarode, Gargi S; Sarode, Sachin C; Patil, Shankargouda

    2017-01-01

    Role of calcium in bone remodeling and tooth remineral-ization is well known. However, calcium also plays a very imperative role in many biochemical reactions, which are essential for normal functioning of cells. The calcium associated tissue homeostasis encompasses activities like proliferation, cell death, cell motility, oxygen, and nutrient supply.

  13. 21 CFR 582.6219 - Calcium phytate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium phytate. 582.6219 Section 582.6219 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium phytate. (a) Product. Calcium phytate. (b) Conditions of use. This substance is...

  14. 21 CFR 582.3189 - Calcium ascorbate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium ascorbate. 582.3189 Section 582.3189 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3189 Calcium ascorbate. (a) Product. Calcium ascorbate. (b) Conditions of use. This substance...

  15. 21 CFR 182.3189 - Calcium ascorbate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium ascorbate. 182.3189 Section 182.3189 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Calcium ascorbate. (a) Product. Calcium ascorbate. (b) Conditions of use. This substance is...

  16. 21 CFR 582.7187 - Calcium alginate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium alginate. 582.7187 Section 582.7187 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium alginate. (a) Product. Calcium alginate. (b) Conditions of use. This substance is...

  17. Calcium Orthophosphate-Based Bioceramics

    Directory of Open Access Journals (Sweden)

    Sergey V. Dorozhkin

    2013-09-01

    Full Text Available Various types of grafts have been traditionally used to restore damaged bones. In the late 1960s, a strong interest was raised in studying ceramics as potential bone grafts due to their biomechanical properties. A bit later, such synthetic biomaterials were called bioceramics. In principle, bioceramics can be prepared from diverse materials but this review is limited to calcium orthophosphate-based formulations only, which possess the specific advantages due to the chemical similarity to mammalian bones and teeth. During the past 40 years, there have been a number of important achievements in this field. Namely, after the initial development of bioceramics that was just tolerated in the physiological environment, an emphasis was shifted towards the formulations able to form direct chemical bonds with the adjacent bones. Afterwards, by the structural and compositional controls, it became possible to choose whether the calcium orthophosphate-based implants remain biologically stable once incorporated into the skeletal structure or whether they were resorbed over time. At the turn of the millennium, a new concept of regenerative bioceramics was developed and such formulations became an integrated part of the tissue engineering approach. Now calcium orthophosphate scaffolds are designed to induce bone formation and vascularization. These scaffolds are often porous and harbor different biomolecules and/or cells. Therefore, current biomedical applications of calcium orthophosphate bioceramics include bone augmentations, artificial bone grafts, maxillofacial reconstruction, spinal fusion, periodontal disease repairs and bone fillers after tumor surgery. Perspective future applications comprise drug delivery and tissue engineering purposes because calcium orthophosphates appear to be promising carriers of growth factors, bioactive peptides and various types of cells.

  18. Natural Dye-Sensitized Solar Cells (NDSSCs) From Opuntia Prickly Pear Dye Using ZnO Doped TiO2 Nanoparticles by Sol-Gel Method

    OpenAIRE

    2014-01-01

    Natural dye-sensitized solar cells (NDSSCs) have gained considerable attention in the field of solar energy due to their simple fabrication, good efficiency, and low production cost. Natural dyes are environmentally and economically superior to ruthenium-based dyes because they are nontoxic and cheap. However, the conversion efficiency of dye-sensitized solar cells based on natural dyes is low. One way to improve the DSSC performance is to enhance the absorptivity of extracted natural dyes. W...

  19. Screening π-conjugated bridges of organic dyes for dye-sensitized solar cells with panchromatic visible light harvesting

    Science.gov (United States)

    Yang, Zhenqing; Liu, Chunmeng; Shao, Changjin; Zeng, Xiaofei; Cao, Dapeng

    2016-07-01

    Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor-π-acceptor (D-π-A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 - BUCT30 dyes show smaller HOMO-LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices.

  20. Effect of dye-metal complexation on photocatalytic decomposition of the dyes on TiO2 under visible irradiation

    Institute of Scientific and Technical Information of China (English)

    MAHMOOD Tariq; CHEN Chuncheng; LIU Lili; ZHAO Dan; MA Wanghong; LIN Jun; ZHAO Jincai

    2009-01-01

    The photocatalytic degradation of dyes (Acid Chrome Blue K (ACBK) and Alizarin Red (AR)) with strong complexation ability was investigated in the presence of metal ions under visible light irradiation.It was found that, at low dye-metal ratio, the photodegradation of ACBK was markedly inhibited by the addition of high oxidative potential Cu2+.However, at high dye-metal ratio, the presence of Cu2+ enhanced the photodegradation of ACBK.The negtive effect of Cu2+ on the photodegradation of AR was observed for all dye-metal ratios.The relative chemical inert Zn2+ tended to enhance the photodegradation of both anionic dyes.The mechanism underlying the different effect of Cu2+ is discussed from the different roles of surface-adsorbed and dye-coordinated Cu2+ in the photodegradation of dyes.

  1. Effect of mercerization and gamma irradiation on the dyeing behaviour of cotton using stilbene based direct dye

    Science.gov (United States)

    Bhatti, Ijaz Ahmad; Adeel, Shahid; Fazal-ur-Rehman; Irshad, Misbah; Abbas, Muhammad

    2012-07-01

    The dyeing behaviour of mercerized and gamma irradiated cotton fabric using stilbene based direct dye has been investigated. The fabric was treated with different concentrations of alkali to optimize the mercerization. The optimum mercerized cotton fabric was irradiated to absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. Dyeing was performed using irradiated and un-irradiated cotton with dye solutions. The dyeing parameters such as temperature, time of dyeing, pH of dyeing solutions and salt concentration were optimized. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton in CIE Lab system using Spectra flash SF650. Methods suggested by International Standard Organization (ISO) were employed to study the effect of gamma irradiation on the colourfastness properties of dyed fabric. It was found that mercerized and irradiated cotton have not only improved the colour strength but enhanced the rating of fastness properties also.

  2. The Structure-property Relationships of D-π-A BODIPY Dyes for Dye-sensitized Solar Cells.

    Science.gov (United States)

    Mao, Mao; Song, Qin-Hua

    2016-04-01

    BODIPY dyes have attracted considerable attention as potential photosensitizers in dye-sensitized solar cells (DSSCs) owing to their excellent optical properties and facile structural modification. This account focuses on recent advances in the molecular design of D-π-A BODIPY dyes for applications in DSSCs. Special attention has been paid to the structure-property relationships of D-π-A BODIPY dyes for DSSCs. The developmental process in the modified position at the BODIPY core with a donor/acceptor is described. The devices based on 2,6-modified BODIPY dyes exhibit better photovoltaic performance over other modified BODIPY dyes. Meanwhile, the research reveals the correlation of molecular structures (various donor chromophores, extended units, molecular frameworks, and long alkyl groups) with their photophysical and electrochemical properties and relates it to their performance in DSSCs. The structure-property relationships give valuable information and guidelines for designing new D-π-A BODIPY dyes for DSSCs.

  3. Towards Rational Designing of Efficient Sensitizers Based on Thiophene and Infrared Dyes for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Ahmad Irfan

    2014-01-01

    Full Text Available Geometries, electronic properties, and absorption spectra of the dyes which are a combination of thiophene based dye (THPD and IR dyes (covering IR region; TIRBD1-TIRBD3 were performed using density functional theory (DFT and time dependent density functional theory (TD-DFT, respectively. Different electron donating groups, electron withdrawing groups, and IR dyes have been substituted on THPD to enhance the efficiency. The bond lengths of new designed dyes are almost the same. The lowest unoccupied molecular orbital energies of designed dyes are above the conduction band of TiO2 and the highest occupied molecular orbital energies are below the redox couple revealing that TIRBD1-TIRBD3 would be better sensitizers for dye-sensitized solar cells. The broad spectra and low energy gap also showed that designed materials would be efficient sensitizers.

  4. Apatite Formation from Amorphous Calcium Phosphate and Mixed Amorphous Calcium Phosphate/Amorphous Calcium Carbonate.

    Science.gov (United States)

    Ibsen, Casper J S; Chernyshov, Dmitry; Birkedal, Henrik

    2016-08-22

    Crystallization from amorphous phases is an emerging pathway for making advanced materials. Biology has made use of amorphous precursor phases for eons and used them to produce structures with remarkable properties. Herein, we show how the design of the amorphous phase greatly influences the nanocrystals formed therefrom. We investigate the transformation of mixed amorphous calcium phosphate/amorphous calcium carbonate phases into bone-like nanocrystalline apatite using in situ synchrotron X-ray diffraction and IR spectroscopy. The speciation of phosphate was controlled by pH to favor HPO4 (2-) . In a carbonate free system, the reaction produces anisotropic apatite crystallites with large aspect ratios. The first formed crystallites are highly calcium deficient and hydrogen phosphate rich, consistent with thin octacalcium phosphate (OCP)-like needles. During growth, the crystallites become increasingly stoichiometric, which indicates that the crystallites grow through addition of near-stoichiometric apatite to the OCP-like initial crystals through a process that involves either crystallite fusion/aggregation or Ostwald ripening. The mixed amorphous phases were found to be more stable against phase transformations, hence, the crystallization was inhibited. The resulting crystallites were smaller and less anisotropic. This is rationalized by the idea that a local phosphate-depletion zone formed around the growing crystal until it was surrounded by amorphous calcium carbonate, which stopped the crystallization.

  5. Detoxification of azo dyes in the context of environmental processes.

    Science.gov (United States)

    Rawat, Deepak; Mishra, Vandana; Sharma, Radhey Shyam

    2016-07-01

    Azo dyes account for >70% of the global industrial demand (∼9 million tons). Owing to their genotoxic/carcinogenic potential, the annual disposal of ∼4,500,000 tons of dyes and/or degraded products is an environmental and socio-economic concern. In comparison to physico-chemical methods, microbe-mediated dye degradation is considered to be low-input, cost-effective and environmentally-safe. However, under different environmental conditions, interactions of chemically diverse dyes with metabolically diverse microbes produce metabolites of varying toxicity. In addition, majority of studies on microbial dye-degradation focus on decolorization with least attention towards detoxification. Therefore, the environmental significance of microbial dye detoxification research of past >3 decades is critically evaluated with reference to dye structure and the possible influence of microbial interactions in different environments. In the absence of ecosystem-based studies, the results of laboratory-based studies on dye degradation, metabolite production and their genotoxic impact on model organisms are used to predict the possible fate and consequences of azo dyes/metabolites in the environment. In such studies, the predominance of fewer numbers of toxicological assays that too at lower levels of biological organization (molecular/cellular/organismic) suggests its limited ecological significance. Based on critical evaluation of these studies the recommendations on inclusion of multilevel approach (assessment at multiple levels of biological organization), multispecies microcosm approach and native species approach in conjunction with identification of dye metabolites have been made for future studies. Such studies will bridge the gap between the fundamental knowledge on dye-microbe-environment interactions and its application to combat dye-induced environmental toxicity. Thus an environmental perspective on dye toxicity in the background of dye structure and effects of

  6. Presynaptic calcium signalling in cerebellar mossy fibres

    DEFF Research Database (Denmark)

    Thomsen, Louiza Bohn; Jörntell, Henrik; Midtgaard, Jens

    2010-01-01

    Whole-cell recordings were obtained from mossy fibre terminals in adult turtles in order to characterize the basic membrane properties. Calcium imaging of presynaptic calcium signals was carried out in order to analyse calcium dynamics and presynaptic GABA B inhibition. A tetrodotoxin (TTX....... Calcium imaging using Calcium-Green dextran revealed a stimulus-evoked all-or-none TTX-sensitive calcium signal in simple and complex rosettes. All compartments of a complex rosette were activated during electrical activation of the mossy fibre, while individual simple and complex rosettes along an axon......)-sensitive fast Na(+) spike faithfully followed repetitive depolarizing pulses with little change in spike duration or amplitude, while a strong outward rectification dominated responses to long-lasting depolarizations. High-threshold calcium spikes were uncovered following addition of potassium channel blockers...

  7. Calcium regulation in endosymbiotic organelles of plants.

    Science.gov (United States)

    Bussemer, Johanna; Vothknecht, Ute C; Chigri, Fatima

    2009-09-01

    In plant cells calcium-dependent signaling pathways are involved in a large array of biological processes in response to hormones, biotic/abiotic stress signals and a variety of developmental cues. This is generally achieved through binding of calcium to diverse calcium-sensing proteins, which subsequently control downstream events by activating or inhibiting biochemical reactions. Regulation by calcium is considered as a eukaryotic trait and has not been described for prokaryotes. Nevertheless, there is increasing evidence indicating that organelles of prokaryotic origin, such as chloroplasts and mitochondria, are integrated into the calcium-signaling network of the cell. An important transducer of calcium in these organelles appears to be calmodulin. In this review we want to give an overview over present data showing that endosymbiotic organelles harbour calcium-dependent biological processes with a focus on calmodulin-regulation.

  8. Store-operated calcium signaling in neutrophils.

    Science.gov (United States)

    Clemens, Regina A; Lowell, Clifford A

    2015-10-01

    Calcium signals in neutrophils are initiated by a variety of cell-surface receptors, including formyl peptide and other GPCRs, FcRs, and integrins. The predominant pathway by which calcium enters immune cells is termed SOCE, whereby plasma membrane CRAC channels allow influx of extracellular calcium into the cytoplasm when intracellular ER stores are depleted. The identification of 2 key families of SOCE regulators, STIM calcium "sensors" and ORAI calcium channels, has allowed for genetic manipulation of SOCE pathways and provided valuable insight into the molecular mechanism of calcium signaling in immune cells, including neutrophils. This review focuses on our current knowledge of the molecules involved in neutrophil SOCE and how study of these molecules has further informed our understanding of the role of calcium signaling in neutrophil activation.

  9. Drosophila mushroom body Kenyon cells generate spontaneous calcium transients mediated by PLTX-sensitive calcium channels.

    Science.gov (United States)

    Jiang, Shaojuan Amy; Campusano, Jorge M; Su, Hailing; O'Dowd, Diane K

    2005-07-01

    Spontaneous calcium oscillations in mushroom bodies of late stage pupal and adult Drosophila brains have been implicated in memory consolidation during olfactory associative learning. This study explores the cellular mechanisms regulating calcium dynamics in Kenyon cells, principal neurons in mushroom bodies. Fura-2 imaging shows that Kenyon cells cultured from late stage Drosophila pupae generate spontaneous calcium transients in a cell autonomous fashion, at a frequency similar to calcium oscillations in vivo (10-20/h). The expression of calcium transients is up regulated during pupal development. Although the ability to generate transients is a property intrinsic to Kenyon cells, transients can be modulated by bath application of nicotine and GABA. Calcium transients are blocked, and baseline calcium levels reduced, by removal of external calcium, addition of cobalt, or addition of Plectreurys toxin (PLTX), an insect-specific calcium channel antagonist. Transients do not require calcium release from intracellular stores. Whole cell recordings reveal that the majority of voltage-gated calcium channels in Kenyon cells are PLTX-sensitive. Together these data show that influx of calcium through PLTX-sensitive voltage-gated calcium channels mediates spontaneous calcium transients and regulates basal calcium levels in cultured Kenyon cells. The data also suggest that these calcium transients represent cellular events underlying calcium oscillations in the intact mushroom bodies. However, spontaneous calcium transients are not unique to Kenyon cells as they are present in approximately 60% of all cultured central brain neurons. This suggests the calcium transients play a more general role in maturation or function of adult brain neurons.

  10. Degradation of azo dyes by environmental microorganisms and helminths

    Energy Technology Data Exchange (ETDEWEB)

    Kingthom Chung; Stevens, S.E. Jr. (Memphis State Univ., TN (United States). Dept. of Biology)

    1993-11-01

    The degradation of azo dyes by environmental microorganisms, fungi, and helminths is reviewed. Azo dyes are used in a wide variety of products and can be found in the effluent of most sewage treatment facilities. Substantial quantities of these dyes have been deposited in the environment, particularly in streams and rivers. Azo dyes were shown to affect microbial activities and microbial population sizes in the sediments and in the water columns of aquatic habitats. Only a few aerobic bacteria have been found to reduce azo dyes under aerobic conditions, and little is known about the process. A substantial number of anaerobic bacteria capable of azo dye reduction have been reported. The enzyme responsible for azo dye reduction has been partially purified, and characterization of the enzyme is proceeding. The nematode Ascaris lumbricoides and the cestode Moniezia expanza have been reported to reduce azo dyes anaerobically. Recently the fungus Phanerochaete chrysoporium was reported to mineralize azo dyes via a peroxidation-mediated pathway. A possible degradation pathway for the mineralization of azo dye is proposed and future research needs are discussed.

  11. Knowledge, attitude, and practice of dyeing and printing workers

    Directory of Open Access Journals (Sweden)

    Paramasivam Parimalam

    2010-01-01

    Full Text Available Background: Millions of workers are occupationally exposed to dyes in the world, but little is known about their knowledge and attitudes toward the effects of dye on their health. Objectives: The aim of this study was to assess the fabric dyers′ and fabric printers′ knowledge, attitude, and practice toward the health hazard of dyes. Materials and Methods: The present study was taken up in the Madurai district which is situated in the Southern Tamil Nadu, India. One hundred and forty-two workers employed in small-scale dyeing and printing units participated in a face-to-face confidential interview . Results: The mean age of fabric dyers and fabric printers was 42 years (΁10.7. When enquired about whether dyes affect body organ(s, all the workers agreed that dye(s will affect skin, but they were not aware that dyes could affect other parts of the body. All the workers believed that safe methods of handling of dyes and disposal of contaminated packaging used for dyes need to be considered. It was found that 34% of the workers were using personal protective equipment (PPE such as rubber hand gloves during work. Conclusion: The workers had knowledge regarding the occupational hazards, and their attitudinal approach toward the betterment of the work environment is positive.

  12. Photophysical properties of pyronin dyes in reverse micelles of AOT

    Energy Technology Data Exchange (ETDEWEB)

    Bayraktutan, Tuğba; Meral, Kadem; Onganer, Yavuz, E-mail: yonganer@atauni.edu.tr

    2014-01-15

    The photophysical properties of pyronin B (PyB) and pyronin Y (PyY) in reverse micelles formed with water/sodium bis (2-ethyl-1-hexyl) sulfosuccinate (AOT)/n-heptane were investigated by UV–vis absorption, steady-state and time-resolved fluorescence spectroscopy techniques. This study was carried out a wide range of reverse micelle sizes, with hydrodynamic radii ranging from 1.85 to 9.38 nm. Significant photophysical parameters as band shifts, fluorescence quantum yields and fluorescence lifetimes were determined to understand how photophysical and spectroscopic features of the dye compounds were affected by the variation of reverse micelle sizes. In this regard, control of reverse micelle size by changing W{sub 0}, the molar ratio of water to surfactant, allowed tuning the photophysical properties of the dyes in organic solvent via reverse micelle. Non-fluorescent H-aggregates of pyronin dyes were observed for the smaller reverse micelles whereas an increase in the reverse micelle size induced an increment in the amount of dye monomers instead of dye aggregates. Thus, the fluorescence intensities of the dyes were improved by increasing W{sub 0} due to the predomination of the fluorescent dye monomers. As a result, the fluorescence quantum yields also increased. The fluorescence lifetimes of the dyes in the reverse micelles were determined by the time-resolved fluorescence decay studies. Evaluation of the fluorescence lifetimes calculated for pyronin dyes in the reverse micelles showed that the size of reverse micelle affected the fluorescence lifetimes of pyronin dyes. -- Highlights: • The photophysical properties of pyronin dyes were examined by spectroscopic techniques. • Optical properties of the dyes were tuned by changing of W{sub 0} values. • The fluorescence lifetime and quantum yield values of the dyes in reverse micelles were discussed.

  13. LIQUID DYES'CHARACTERISTICS IN DYEING WASTE PAPER PULP AND THEIR APPLICATION

    Institute of Scientific and Technical Information of China (English)

    XiaopingWang; gangChen; AiminTang; HongweiZhang

    2004-01-01

    In this paper, some liquid dyes were used to dye the waste paper pulp (OCC pulp and waste cement sack paper pulp), and their dyeing characteristics were analyzed, The liquid dyes include liquid basic yellow, liquid basic blue, liquid basic red, liquid basic orange, liquid basic brown and liquid direct black. We found that, each dye had its own dyeing characteristic while dyeing the waste paper pulp. Generally different types of liquid dyes were combined to dye the waste paper pulp, which the adding process must be noticed. We also observed that a black pigment could be applied together withsaid liquid dyes to dye or adjust the color of the bottom sheet for the fireproof board. We could also achieve the same dyeing result through different combinations of different dyes.

  14. Optoelectronic properties of natural cyanin dyes.

    Science.gov (United States)

    Calzolari, A; Varsano, D; Ruini, A; Catellani, A; Tel-Vered, R; Yildiz, H B; Ovits, O; Willner, I

    2009-07-30

    An integrated theoretical/experimental study of the natural cyanin dye is presented in terms of its structural and optoelectronic properties for different gas-phase and prototypical device configurations. Our microscopic analysis reveals the impact of hydration and hydroxylation reactions, as well as of the attached sugar, on ground and optically excited states, and it illustrates the visible-light harvesting capability of the dye. Our optical experiments at different and controlled pH concentrations allow for a direct comparison with theoretical results. We analyze the many different contributions to photocurrent of the various portions of a prototypical device and, as a proof of principle, we propose the addition of specific ligands to control the increase of the photocurrent yield in the cyanin-based electrochemical device.

  15. Nanoimprinted polymer photonic crystal dye lasers

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Smith, Cameron; Buss, Thomas

    2010-01-01

    Optically pumped polymer photonic crystal band-edge dye lasers are presented. The photonic crystal is a rectangular lattice providing laser feedback as well as an optical resonance for the pump light. The lasers are defined in a thin film of photodefinable Ormocore hybrid polymer, doped...... with the laser dye Pyrromethene 597. A compact frequency doubled Nd:YAG laser (352 nm, 5 ns pulses) is used to pump the lasers from above the chip. The laser devices are 450 nm thick slab waveguides with a rectangular lattice of 100 nm deep air holes imprinted into the surface. The 2-dimensional rectangular...... lattice is described by two orthogonal unit vectors of length a and b, defining the P and X directions. The frequency of the laser can be tuned via the lattice constant a (187 nm - 215 nm) while pump light is resonantly coupled into the laser from an angle () depending on the lattice constant b (355 nm...

  16. Dye-Sensitized Approaches to Photovoltaics

    Science.gov (United States)

    Grätzel, Michael

    2008-03-01

    Sensitization of wide band-gap semiconductors to photons of energy less than the band-gap is a key step in two technically important processes - panchromatic photography and photoelectrochemical solar cells. In both cases the photosensitive species is not the semiconductor - silver halide or metal oxide - but rather an electrochemically active dye. The gap between the highest occupied molecular level (HOMO) and the lowest unoccupied molecular level (LUMO) is less than the band-gap of the semiconductor with which it is associated. It can therefore absorb light of a wavelength longer than that to which the semiconductor itself is sensitive. The electrochemical process is initiated when the dye molecule relaxes from its photoexcited level by electron injection into the semiconductor, which therefore acts as a photoanode. If the dye is in contact with a redox electrolyte, the negative charge represented by the lost electron can be recovered from the reduced state of the redox system, which in return is regenerated by charge transfer from a cathode. An external load completes the electrical circuit. The system therefore represents a conversion of the energy of absorbed photons into an electrical current by a regenerative device in every functional respect analogous to a solid-state photovoltaic cell. As in any engineering system, choice of materials, their optimization and their synergy are essential to efficient operation. While a semiconductor-electrolyte contact is analogous to a Schottky contact, in that a barrier is established between two materials of different conduction mechanism, with the possibility of optical absorption, charge carrier pair generation and separation, it should be remembered that the photogenerated valence band hole in the semiconductor represents a powerful oxidizing agent. Given that the band-gap is related to the strength and therefore the stability of chemical bonding within the semiconductor, for narrow-gap materials the most likely

  17. Molecular modification of coumarin dyes for more efficient dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-de-Armas, Rocio; San-Miguel, Miguel A.; Oviedo, Jaime; Sanz, Javier Fdez. [Department of Physical Chemistry, University of Seville, Seville (Spain)

    2012-05-21

    In this work, new coumarin based dyes for dye sensitized solar cells (DSSC) have been designed by introducing several substituent groups in different positions of the NKX-2311 structure. Two types of substitutions have been considered: the introduction of three electron-donating groups (-OH, -NH{sub 2}, and -OCH{sub 3}) and two different substituents with steric effect: -CH{sub 2}-CH{sub 2}-CH{sub 2}- and -CH{sub 2}-HC=CH-. The electronic absorption spectra (position and width of the first band and absorption threshold) and the position of the LUMO level related to the conduction band have been used as theoretical criteria to evaluate the efficiency of the new dyes. The introduction of a -NH{sub 2} group produces a redshift of the absorption maximum position and the absorption threshold, which could improve the cell efficiency. In contrast, the introduction of -CH{sub 2}-CH{sub 2}-CH{sub 2}- does not modify significantly the electronic structure of NKX-2311, but it might prevent aggregation. Finally, -CH{sub 2}-HC=CH- produces important changes both in the electronic spectrum and in the electronic structure of the dye, and it would be expected as an improvement of cell efficiency for these dyes.

  18. Effects of reduction products of ortho-hydroxyl substituted azo dyes on biodecolorization of azo dyes

    Energy Technology Data Exchange (ETDEWEB)

    Liu Guangfei [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Wang Jing, E-mail: wangjingbio@yahoo.cn [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Lu Hong; Jin Ruofei; Zhou Jiti; Zhang Long [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China)

    2009-11-15

    The mediated effects of reduction products of some ortho-hydroxyl substituted azo dyes on biodecolorization were investigated. The results indicated that the addition of reduction products could effectively accelerate dye decolorization by Shigella sp. QRZ-1. The best accelerating effect was obtained with the addition of reduction products of Acid Red 14 (AR14), resulting in an over 3-fold increase in decolorization efficiency of many azo dyes. In sequencing batch reactor experiments, the accelerating effect of reduction products of AR14 was more obvious (1.5-fold) during the startup of the system. When the dye concentration was increased to 500 mg L{sup -1}, the accelerated decolorization efficiency was still maintained around 95%. The presence of AR14 in the feed enhanced the decolorization performance of anaerobic sludge, indicating that the strategy may be beneficial for practical application. 1-Naphthol-2-amino-4-sulfonic acid, which is one of the reduction products of AR14, may function as redox mediator to speed up azo dye biodecolorization.

  19. Novel organic dyes based on phenyl-substituted benzimidazole for dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saltan, Gözde Murat [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Dinçalp, Haluk, E-mail: haluk.dincalp@cbu.edu.tr [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Kıran, Merve; Zafer, Ceylan [Solar Energy Institute, Ege University, Bornova, 35100 Izmir (Turkey); Erbaş, Seçil Çelik [Celal Bayar University, Materials Engineering Department, Faculty of Engineering, Yunus Emre, 45140 Manisa (Turkey)

    2015-08-01

    Two new sensitizers derived from benzimidazole core for dye-sensitized solar cell (DSSC) applications were designed and synthesized as D–π–A structures, in which two phenyl-substituted benzimidazole group, a phenyl ring and a cyanoacrylic acid were used as the electron donor, π-conjugated linkage and the electron acceptor, respectively. Effect of methoxy- and N,N-dimetylamino- moieties attached to the phenyl groups of benzimidazole were investigated by means of optical and photovoltaic measurements. The compounds exhibit broad absorption maximum at 387 nm with the tail extending up to 500 nm on TiO{sub 2}-coated thin film. The longer wavelength absorption band around 360 nm and the much longer decay components could be attributed to the existence of charge transfer state of the dyes in solutions. DSSC device fabricated by using methoxy substituted dye (BI5a) as a sensitizer shows much better incident photon-to-current conversion efficiency (IPCE) of 64% giving cell efficiency of 2.68%. - Graphical abstract: Display Omitted - Highlights: • Long decay times suggest the delayed fluorescence caused by the existence of ICT. • The best solar energy conversion efficiency was obtained for BI5a dye (2.68%). • More fluorescent BI5a dye gives higher photocurrent generation.

  20. Calcium channel antagonists in hypertension.

    Science.gov (United States)

    Ambrosioni, E; Borghi, C

    1989-02-01

    The clinical usefulness of calcium entry-blockers for the treatment of high blood pressure is related to their capacity to act upon the primary hemodynamic derangement in hypertension: the increased peripheral vascular resistance. They can be used alone or in combination with other antihypertensive agents for the treatment of various forms of hypertensive disease. The calcium entry-blockers appear to be the most useful agents for the treatment of hypertension in the elderly and for the treatment of hypertension associated with ischemic heart disease, pulmonary obstructive disease, peripheral vascular disease, and supraventricular arrhythmias. They are effective in reducing blood pressure in pregnancy-associated hypertension and must be considered as first-line therapy for the treatment of hypertensive crisis.

  1. Dye Fluorescence Analysis from Bacterial Metabolism.

    Science.gov (United States)

    1984-04-01

    M were reported for the cell-free extracts of the cultured mouse lymphoma cells mentioned above and an in vitAo solution of porcine pancreas lipase ...fluorescence Fluorescent product Diacetyl fluorescein Lipase Bacterial metabolism 20. ABTRACT fCauhw a o de dif rNooeel md ~Id1)fp by block number) A...nonfluorescing dye is metabolized intracel- lularly by an organism through an enzyme-specific reaction . This produces a fluorescent product which when

  2. Plasmonic Dye-Sensitized Solar Cells

    KAUST Repository

    Ding, I-Kang

    2010-12-14

    This image presents a scanning electron microscopy image of solid state dye-sensitized solar cell with a plasmonic back reflector, overlaid with simulated field intensity plots when monochromatic light is incident on the device. Plasmonic back reflectors, which consist of 2D arrays of silver nanodomes, can enhance absorption through excitation of plasmonic modes and increased light scattering, as reported by Michael D. McGehee, Yi Cui, and co-workers.

  3. Indanthrone dye revisited after sixty years.

    Science.gov (United States)

    Kotwica, Kamil; Bujak, Piotr; Wamil, Damian; Materna, Mariusz; Skorka, Lukasz; Gunka, Piotr A; Nowakowski, Robert; Golec, Barbara; Luszczynska, Beata; Zagorska, Malgorzata; Pron, Adam

    2014-10-09

    Indanthrone, an old, insoluble dye can be converted into a solution processable, self-assembling and electroluminescent organic semiconductor, namely tetraoctyloxydinaptho[2,3-a:2',3'-h]phenazine (P-C8), in a simple one-pot process consisting of the reduction of the carbonyl group by sodium dithionite followed by the substitution with solubility inducing groups under phase transfer catalysis conditions.

  4. Dyeing of Snow Surfaces to Observe Structure

    Science.gov (United States)

    1993-06-01

    of freezeup problems important to obtain a clear visual perspective and with water. We found that both coloring agents to obtain good photographic...a dye of methanol coloring in with floodlights, whereas Figure 7b is a view of the water. Freezeup at the sprayer nozzle was one same area lighted...from behind, problem and the snow surface had a blemished appearance because of the addition of the water, which then froze. Freezeup may not be a

  5. The calcium-alkali syndrome

    OpenAIRE

    Arroyo, Mariangeli; Fenves, Andrew Z.; Emmett, Michael

    2013-01-01

    The milk-alkali syndrome was a common cause of hypercalcemia, metabolic alkalosis, and renal failure in the early 20th century. It was caused by the ingestion of large quantities of milk and absorbable alkali to treat peptic ulcer disease. The syndrome virtually vanished after introduction of histamine-2 blockers and proton pump inhibitors. More recently, a similar condition called the calcium-alkali syndrome has emerged as a common cause of hypercalcemia and alkalosis. It is usually caused b...

  6. Calcium phosphate polymer hybrid materials

    OpenAIRE

    2011-01-01

    Calcium phosphate (CaP) is of strong interest to the medical field because of its potential for bone repair, gene transfection, etc.1-3 Nowadays, the majority of the commercially available materials are fabricated via “classical” materials science approaches, i.e. via high temperature or high pressure approaches, from rather poorly defined slurries, or from organic solvents.3,4 Precipitation of inorganics with (polymeric) additives from aqueous solution on the other hand enables the synthesis...

  7. Electrochemical removal of dyes from textile wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Uhrich, K.D. (Andco Environmental Processes, Inc., Amherst, NY (USA))

    1988-09-01

    There are many technologies available for treating wastewater from the textile industry. Included are (1) biological treatment, (2) chemical precipitation, (3) carbon absorption, (4) ultrafiltration, and (5) oxidation with ozone. The main drawback of these technologies is that they generally lack the broad scope of treatment efficiency required to reduce all types of pollutants present in textile wastewater. However, when one approach does look promising, its capital costs or operating costs often become prohibitive when applied to the large water needs common to this industry. It has recently been shown that an electrochemical technology developed in the 1970s by Andco Environmental Processes, Inc. effectively removes many of the contaminants including toxic dye species and heavy metals along with significant BOD and COD reduction across many types of textile wastewater and dye species. The removal of dyes and other pollutants in textile wastewater can be accomplished very efficiently with the electrochemical process. Actual operating data, along with actual water samples, will be presented along with economics and operating characteristics of this type of a system. Additional considerations such as removal of other components such as BOD and COD, theoretical interpretations, and the possibility of water reuse will also be discussed.

  8. Plastic encapsulated, dye sensitised photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Potter, R.J.; Otley, L.C.; Durrant, J.R.; Haque, S.; Xu, C. [Imperial College of Science, Technology and Medicine, London (United Kingdom); Holmes, A.B.; Park, T.; Schulte, N. [Cambridge Univ. (United Kingdom)

    2004-07-01

    The report presents the results of a collaborative project that aimed to demonstrate the technical feasibility of a plastic-encapsulated, solid state, dye-sensitised solar cell (DSSC) with an energy conversion efficiency (ECE) of at least 3%. DSSCs offer a possible 'step change' in photovoltaic technology resulting in lower costs compared with existing technologies. The project involved a series of eight main tasks: the development of first and second generation HTM electrolytes; the development of polymer-supported electrolytes; the development of low temperature electrode coating procedures; dye development; cell assembly and testing; component integration; and overall process development. A wide range of innovative HTMs have been synthesised, including materials incorporating both hole-transporting and ion-chelating functional groups. The ruthenium-based dye, N3, remained the preferred sensitising component. The project has produced a system that can routinely achieve over 5% ECE at 0.1 Sun illumination on 1 cm{sup 2} cells using polymer-supported electrolytes.

  9. Decolorization of azo dyes in bioelectrochemical systems.

    Science.gov (United States)

    Mu, Yang; Rabaey, Korneel; Rozendal, René A; Yuan, Zhiguo; Keller, Jürg

    2009-07-01

    Azo dyes are ubiquitously used in the textile industry. These dyes need to be removed from the effluent prior to discharge to sewage due to their intense color and toxicity. In this study we investigated the use of a bioelectrochemical system (BES) to abioticlly cathodic decolorization of a model azo dye, Acid Orange 7 (AO7), where the process was driven by microbial oxidation of acetate atthe anode. Effective decolorization of AO7 at rates up to 264 +/- 0.03 mol m(-3) NCC d(-1) (net cathodic compartment, NCC) was achieved at the cathode, with concomitant energy recovery. The AO7 decolorization rate was significantly enhanced when the BES was supplied with power, reaching 13.18 +/- 0.05 mol m(-3) NCC d(-1) at an energy consumption 0.012 +/- 0.001 kWh mol(-1) AO7 (at a controlled cathode potential of -400 mV vs SHE). Compared with conventional anaerobic biological methods, the required dosage of organic cosubstrate was significantly reduced in the BES. A possible cathodic reaction mechanism for the decolorization of AO7 is suggested based on the decolorization products identified: the azo bond of AO7 was cleaved at the cathode, resulting in the formation of the colorless sulfanilic acid and 1-amino-2-naphthol.

  10. Dyes and Redox Couples with Matched Energy Levels: Elimination of the Dye-Regeneration Energy Loss in Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Jiang, Dianlu; Darabedian, Narek; Ghazarian, Sevak; Hao, Yuanqiang; Zhgamadze, Maxim; Majaryan, Natalie; Shen, Rujuan; Zhou, Feimeng

    2015-11-16

    In dye-sensitized solar cells (DSSCs), a significant dye-regeneration force (ΔG(reg)(0)≥0.5 eV) is usually required for effective dye regeneration, which results in a major energy loss and limits the energy-conversion efficiency of state-of-art DSSCs. We demonstrate that when dye molecules and redox couples that possess similar conjugated ligands are used, efficient dye regeneration occurs with zero or close-to-zero driving force. By using Ru(dcbpy)(bpy)2(2+) as the dye and Ru(bpy)2(MeIm)2(3+//2+) as the redox couple, a short-circuit current (J(sc)) of 4 mA cm(-2) and an open-circuit voltage (V(oc)) of 0.9 V were obtained with a ΔG(reg)(0) of 0.07 eV. The same was observed for the N3 dye and Ru(bpy)2(SCN)2(1+/0) (ΔG(reg)(0)=0.0 eV), which produced an J(sc) of 2.5 mA cm(-2) and V(oc) of 0.6 V. Charge recombination occurs at pinholes, limiting the performance of the cells. This proof-of-concept study demonstrates that high V(oc) values can be attained by significantly curtailing the dye-regeneration force.

  11. 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 ...

  12. Synthesis and investigation of antimicrobial activity and spectrophotometric and dyeing properties of some novel azo disperse dyes based on naphthalimides.

    Science.gov (United States)

    Shaki, Hanieh; Gharanjig, Kamaladin; Khosravi, Alireza

    2015-01-01

    A series of novel disperse dyes containing azo group were synthesized through a diazotization and coupling process. The 4-amino-N-2-aminomethylpyridine-1,8-naphthalimide was diazotized by nitrosylsulphuric acid and coupled with various aromatic amines such as N,N-diethylaniline, N,N-dihydroxyethylaniline, 8-hydroxyquinoline, and 2-methylindole. Chemical structures of the synthesized dyes were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), proton nuclear magnetic resonance ((1) H NMR), carbon nuclear magnetic resonance ((13) C NMR), elemental analysis, and ultraviolet-visible (UV-visible) spectroscopy. The spectrophotometric data of all dyes were evaluated in various solvents with different polarity. Eventually, the dyes were applied on polyamide fabrics in order to investigate their dyeing properties. The fastness properties of the dyed fabrics such as wash, light, and rubbing fastness degrees were measured by standard methods. Moreover, the color gamut of the synthesized dyes was measured on polyamide fabrics. Results indicated that some of the synthesized dyes were able to dye polyamide fabrics with deep shades. They had very good wash and rubbing fastness degrees and moderate-to-good light fastness on polyamide fabrics. The antibacterial and antifungal activities of the synthesized dyes were evaluated in soluble state and on the dyed fabrics. The results indicated that dye 2 containing N,N-dihydroxyethylaniline as coupler had the highest activity against all the bacteria and fungi used.

  13. Structure-performance correlations of organic dyes with an electron-deficient diphenylquinoxaline moiety for dye-sensitized solar cells.

    Science.gov (United States)

    Li, Sie-Rong; Lee, Chuan-Pei; Yang, Po-Fan; Liao, Chia-Wei; Lee, Mandy M; Su, Wei-Lin; Li, Chun-Ting; Lin, Hao-Wu; Ho, Kuo-Chuan; Sun, Shih-Sheng

    2014-08-04

    The high performances of dye-sensitized solar cells (DSSCs) based on seven new dyes are disclosed. Herein, the synthesis and electrochemical and photophysical properties of a series of intentionally designed dipolar organic dyes and their application in DSSCs are reported. The molecular structures of the seven organic dyes are composed of a triphenylamine group as an electron donor, a cyanoacrylic acid as an electron acceptor, and an electron-deficient diphenylquinoxaline moiety integrated in the π-conjugated spacer between the electron donor and acceptor moieties. The DSSCs based on the dye DJ104 gave the best overall cell performance of 8.06 %; the efficiency of the DSSC based on the standard N719 dye under the same experimental conditions was 8.82 %. The spectral coverage of incident photon-to-electron conversion efficiencies extends to the onset at the near-infrared region due to strong internal charge-transfer transition as well as the effect of electron-deficient diphenylquinoxaline to lower the energy gap in these organic dyes. A combined tetraphenyl segment as a hydrophobic barrier in these organic dyes effectively slows down the charge recombination from TiO2 to the electrolyte and boosts the photovoltage, comparable to their Ru(II) counterparts. Detailed spectroscopic studies have revealed the dye structure-cell performance correlations, to allow future design of efficient light-harvesting organic dyes.

  14. Investigation of hair dye deposition, hair color loss, and hair damage during multiple oxidative dyeing and shampooing cycles.

    Science.gov (United States)

    Zhang, Guojin; McMullen, Roger L; Kulcsar, Lidia

    2016-01-01

    Color fastness is a major concern for consumers and manufacturers of oxidative hair dye products. Hair dye loss results from multiple wash cycles in which the hair dye is dissolved by water and leaches from the hair shaft. In this study, we carried out a series of measurements to help us better understand the kinetics of the leaching process and pathways associated with its escape from the fiber. Hair dye leaching kinetics was measured by suspending hair in a dissolution apparatus and monitoring the dye concentration in solution (leached dye) with an ultraviolet-visible spectrophotometer. The physical state of dye deposited in hair fibers was evaluated by a reflectance light microscopy technique, based on image stacking, allowing enhanced depth of field imaging. The dye distribution within the fiber was monitored by infrared spectroscopic imaging of hair fiber cross sections. Damage to the ultrafine structure of the hair cuticle (surface, endocuticle, and cell membrane complex) and cortex (cell membrane complex) was determined in hair cross sections and on the hair fiber surface with atomic force microscopy. Using differential scanning calorimetry, we investigated how consecutive coloring and leaching processes affect the internal proteins of hair. Further, to probe the surface properties of hair we utilized contact angle measurements. This study was conducted on both pigmented and nonpigmented hair to gain insight into the influence of melanin on the hair dye deposition and leaching processes. Both types of hair were colored utilizing a commercial oxidative hair dye product based on pyrazole chemistry.

  15. CCN3 and calcium signaling

    Directory of Open Access Journals (Sweden)

    Li Chang Long

    2003-08-01

    Full Text Available Abstract The CCN family of genes consists presently of six members in human (CCN1-6 also known as Cyr61 (Cystein rich 61, CTGF (Connective Tissue Growth Factor, NOV (Nephroblastoma Overexpressed gene, WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins. Results obtained over the past decade have indicated that CCN proteins are matricellular proteins, which are involved in the regulation of various cellular functions, such as proliferation, differentiation, survival, adhesion and migration. The CCN proteins have recently emerged as regulatory factors involved in both internal and external cell signaling. CCN3 was reported to physically interact with fibulin-1C, integrins, Notch and S100A4. Considering that, the conformation and biological activity of these proteins are dependent upon calcium binding, we hypothesized that CCN3 might be involved in signaling pathways mediated by calcium ions. In this article, we review the data showing that CCN3 regulates the levels of intracellular calcium and discuss potential models that may account for the biological effects of CCN3.

  16. Store-Operated Calcium Channels.

    Science.gov (United States)

    Prakriya, Murali; Lewis, Richard S

    2015-10-01

    Store-operated calcium channels (SOCs) are a major pathway for calcium signaling in virtually all metozoan cells and serve a wide variety of functions ranging from gene expression, motility, and secretion to tissue and organ development and the immune response. SOCs are activated by the depletion of Ca(2+) from the endoplasmic reticulum (ER), triggered physiologically through stimulation of a diverse set of surface receptors. Over 15 years after the first characterization of SOCs through electrophysiology, the identification of the STIM proteins as ER Ca(2+) sensors and the Orai proteins as store-operated channels has enabled rapid progress in understanding the unique mechanism of store-operate calcium entry (SOCE). Depletion of Ca(2+) from the ER causes STIM to accumulate at ER-plasma membrane (PM) junctions where it traps and activates Orai channels diffusing in the closely apposed PM. Mutagenesis studies combined with recent structural insights about STIM and Orai proteins are now beginning to reveal the molecular underpinnings of these choreographic events. This review describes the major experimental advances underlying our current understanding of how ER Ca(2+) depletion is coupled to the activation of SOCs. Particular emphasis is placed on the molecular mechanisms of STIM and Orai activation, Orai channel properties, modulation of STIM and Orai function, pharmacological inhibitors of SOCE, and the functions of STIM and Orai in physiology and disease.

  17. Kinetics of calcium sulfoaluminate formation from tricalcium aluminate, calcium sulfate and calcium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xuerun, E-mail: xuerunli@163.com; Zhang, Yu; Shen, Xiaodong, E-mail: xdshen@njut.edu.cn; Wang, Qianqian; Pan, Zhigang

    2014-01-15

    The formation kinetics of tricalcium aluminate (C{sub 3}A) and calcium sulfate yielding calcium sulfoaluminate (C{sub 4}A{sub 3}$) and the decomposition kinetics of calcium sulfoaluminate were investigated by sintering a mixture of synthetic C{sub 3}A and gypsum. The quantitative analysis of the phase composition was performed by X-ray powder diffraction analysis using the Rietveld method. The results showed that the formation reaction 3Ca{sub 3}Al{sub 2}O{sub 6} + CaSO{sub 4} → Ca{sub 4}Al{sub 6}O{sub 12}(SO{sub 4}) + 6CaO was the primary reaction < 1350 °C with and activation energy of 231 ± 42 kJ/mol; while the decomposition reaction 2Ca{sub 4}Al{sub 6}O{sub 12}(SO{sub 4}) + 10CaO → 6Ca{sub 3}Al{sub 2}O{sub 6} + 2SO{sub 2} ↑ + O{sub 2} ↑ primarily occurred beyond 1350 °C with an activation energy of 792 ± 64 kJ/mol. The optimal formation region for C{sub 4}A{sub 3}$ was from 1150 °C to 1350 °C and from 6 h to 1 h, which could provide useful information on the formation of C{sub 4}A{sub 3}$ containing clinkers. The Jander diffusion model was feasible for the formation and decomposition of calcium sulfoaluminate. Ca{sup 2+} and SO{sub 4}{sup 2−} were the diffusive species in both the formation and decomposition reactions. -- Highlights: •Formation and decomposition of calcium sulphoaluminate were studied. •Decomposition of calcium sulphoaluminate combined CaO and yielded C{sub 3}A. •Activation energy for formation was 231 ± 42 kJ/mol. •Activation energy for decomposition was 792 ± 64 kJ/mol. •Both the formation and decomposition were controlled by diffusion.

  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. [Thapsigargin-sensitive and insensitive intracellular calcium stores in acinar cells of the submandibular salivary gland in rats].

    Science.gov (United States)

    Kopach, O V; Kruhlykov, I A; Voĭtenko, N V; Fedirko, N V

    2005-01-01

    Acinar cells of rat submandibular salivary gland are characterized by heterogeneity of intracellular Ca2+ stores. In the present work we have studied this heterogeneity using Arsenazo III dye to measure a cellular total calcium content and Fura-2/AM, to determine free cytosolic calcium concentration ([Ca2+]i). We have found that the amount of Ca2+ released by inhibition of Ca2+ ATPase of the ER with thapsigargin comprises approximately 30% of total ER calcium. This result was obtained in experiments on both intact and permeabilized acinar cells. We have also shown that both Ca2+ ATPase inhibition with thapsigargin and emptying the stores with acetylcholine (ACh) led to activation of store-operated Ca2+ influx (an increase in total calcium content of approximately 14%). In permeabilized cells application of ACh after preincubation with thapsigargin led to a further decrease in total cellular calcium content (approximately 38%). At the same time in intact cells it resulted in generation of [Ca2+]i transients with gradually decreasing amplitudes. Thus, ACh is capable of producing an additional release of Ca2+ from thapsigargin-insensitive stores. This additional release is IP3-dependent since it was completely blocked by heparin. We conclude that in acinar cells of rat submandibular gland thapsigargin-sensitive and thapsigargin-insensitive Ca2+ stores could exist.

  20. New portable time-resolved photometer for monitoring the calcium dynamics of osteoblasts under mechanical and zero-gravity stimulation

    Science.gov (United States)

    Struckmeier, Jens; Tenbosch, Jochen; Klopp, Erk; Born, Matthias; Hofmann, Martin R.; Jones, David B.

    2000-04-01

    We introduce a compact and portable photometric system for measurements of the calcium dynamics in cells. The photometer is designed for applications in centrifuges or in zero-gravity environment and thus extremely compact and reliable. It operates with the calcium-sensitive dye Indo-1. The excitation wavelength of 345nm is generated by frequency doubling of a laser diode. Two compact photomultiplier tubes detect the fluorescent emission. The electronics provides the sensitivity of photon counting combined with simultaneous measurement of the temperature, of air pressure, and of gravitational force. Internal data storage during the experiment is possible. A newly developed cell chamber stabilizes the cell temperature to 37.0 percent C +/- 0.1 degree C and includes a perfusion system to supply the cells with medium. The system has a modular set-up providing the possibility to change light source and detectors for investigation of other ions than calcium. Quantitative measurements of the intracellular calcium concentration are based on a comprehensive calibration of our system. First experiments show that the calcium dynamics of osteosarcoma cells stimulated by parathyroid hormone is observable.

  1. Dyes extracted from Trigonella seeds as photosensitizers for dye-sensitized solar cells

    Science.gov (United States)

    Batniji, Amal; Abdel-Latif, Monzir S.; El-Agez, Taher M.; Taya, Sofyan A.; Ghamri, Hatem

    2016-12-01

    In this paper, the extract of Trigonella seeds was used as sensitizer for dye-sensitized solar cells (DSSCs). The natural dye was extracted from the seeds using water and alcohol as solvents for the raw material. The UV-Vis absorption spectra of Trigonella extract solution and dye adsorbed on TiO2 film were measured. DSSCs sensitized by Trigonella extracted using water as a solvent exhibited better performance with efficiency of 0.215 %. The performance of the fabricated DSSCs was attempted to enhance by acid treatment of the FTO substrates with HNO3, H3PO4, and H2SO4. Electrochemical impedance spectroscopy of the fabricated cells was also carried out.

  2. Dyeing of wool fibres with natural dyes: effect of proteolytic enzymes.

    Science.gov (United States)

    Doğru, Mehmet; Baysal, Zübeyde; Aytekin, Cetin

    2006-01-01

    In spite of the widespread use of proteins (casein, peptone, etc.) and protein fragments as a substrate for the proteolytic enzymes, a substrate prepared from dyes that adsorb onto appropriate materials, such as wool and cotton, are also used for enzyme activity determination. In the point of view of this thought, it was our aim to develop the substrates which are easily and economically obtainable and also environmentally safer for the frequently used proteolytic enzymes, such as subtilisin carlsberg, trypsin, chymotrypsin, and protease type XVI and, if possible, to prepare the specific substrate at least for one of these enzymes. For this aim, wool was dyed with natural dyes such as juglone, lawsone, berberine, and quercetin. The optimum pH, incubation time, and agitation rate were determinated. The results indicate that, of all the tested enzymes on wool-dye complex as an insoluble substrate, the most appropriate complex was found to be wool-lawsone complex.

  3. Dyeing of Polyester and Polyamide Synthetic Fabrics with Natural Dyes Using Ecofriendly Technique

    Directory of Open Access Journals (Sweden)

    Khaled Elnagar

    2014-01-01

    Full Text Available This work presents an ecofriendly method for dyeing synthetic fabrics with natural dyes using UV/ozone pretreatment to activate fiber and improve dyeability of polyester and nylon. Fabrics are pretreated with UV/ozone for different periods of time ranged from 5 min to 120 min. Effect of pretreatment on surface morphology was studied by scanning electron microscope (SEM. Mechanical behavior was studied by testing tensile strength and elongation percentage. Chemical modification of the surface was studied using attenuated total reflection Fourier transform infrared spectrometer (ATR-FTIR. Dyeability of the treated samples was investigated in terms of their colour strength expressed as K/s in addition to fastness to washing and light. This research showed the increment of the affinity of the studied synthetic fabrics towards curcumin and saffron natural dyes using ecofriendly technique.

  4. Dyes extracted from Trigonella seeds as photosensitizers for dye-sensitized solar cells

    Science.gov (United States)

    Batniji, Amal; Abdel-Latif, Monzir S.; El-Agez, Taher M.; Taya, Sofyan A.; Ghamri, Hatem

    2016-06-01

    In this paper, the extract of Trigonella seeds was used as sensitizer for dye-sensitized solar cells (DSSCs). The natural dye was extracted from the seeds using water and alcohol as solvents for the raw material. The UV-Vis absorption spectra of Trigonella extract solution and dye adsorbed on TiO2 film were measured. DSSCs sensitized by Trigonella extracted using water as a solvent exhibited better performance with efficiency of 0.215 %. The performance of the fabricated DSSCs was attempted to enhance by acid treatment of the FTO substrates with HNO3, H3PO4, and H2SO4. Electrochemical impedance spectroscopy of the fabricated cells was also carried out.

  5. Synthesis of Calix[4]resorcinarene Based Dyes and its Application in Dyeing of Fibres

    Directory of Open Access Journals (Sweden)

    Vinod K. Jain

    2008-01-01

    Full Text Available Four new ʻupper rimʼ azocalix[4]resorcinarene have been synthesized by coupling calix[4]resorcinarene with different diazotized aromatic compounds of sulphanilic acid, anthranilic acid, o-aminophenol and p-aminobenzoic acid. The prepared compounds were characterized based on m.p., elemental analysis, FT-IR, 1H-NMR. These dyes have been used for the dyeing of textile fibres like cotton and wool. Their fastness properties such as fastness to sunlight, water, washings, and perspiration have also been studied. The synthesized dyes have been employed for computerized colour strength determination through colour matching with known standards. Their L, A*, B* values as well as the colour difference values such as ∆L, ∆A*, ∆B*, ∆C and ∆H have also been reported.

  6. Progress in modifications and applications of fluorescent dye probe

    Institute of Scientific and Technical Information of China (English)

    Xuening Fei; Yingchun Gu

    2009-01-01

    This review summarizes the labeling technology and applications of fluorescent dye probe in biology,especially the characteristics,modifications and applications of cyanine dyes.Based on the currently available modification methods of fluorescent dye probe,we discuss the studies of enhancing the water-solubility,improving the degree of biocompatibility and target-labeling,increasing the sensitivity and decreasing the toxicity of fluorescent dye.We also give a brief introduction on the modification method,that the fluorescent dye is directly introduced onto the cell surfaces by amine derivatives or azides to intensify the transferring information of aberrant cells.We suggest that fluorescent dye modified with chitosan oligosaccharide can obviously increase the degree of biocompatibility and targetlabeling,and decrease the degree of toxicity.

  7. Wood Microstructure Effects on Chinese White Poplar Dyeing

    Institute of Scientific and Technical Information of China (English)

    DUANXinfang; BAOFucheng

    2004-01-01

    In order to study the influence of wood microstructure on wood dyeing, eleven parameters of wood microstructure and 5 parameters of wood dyeing effects for 34 pieces of wood boards from 5 trees of Chinese white poplar (Populus tornentosa) were determined and the multiple regression analysis between the factors of wood microstructures and the parameters of wood dyeing effects were made. The regression results show that each variable of wood dyeing effects has higher relationship with wood microstructures,and multiple correlation coefficients between each variable of wood dyeing effects and wood microstructures are 0.483 6-0.799 8. The main factors of wood microstructures influencing wood dyeing of Chinese whitep oplar are proportion of wood ray, proportion of vessel and proportion of wood fiber according to comparing the standardized regression coefficients of multiple regression equation.

  8. Decolorization of Anthraquinone dye by Rhodopseudomonas XL-1

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Rhodopseudomonas XL-1 gained from textile wastewater can effectively decolorize anthraquinone dye. Under anaerobic condition, 93 percent of the anthraquinone dye is decolorized , which is higher than that under aerobic condition. The optimum pH is 6~9 and the optimum temperature is 20~40℃ for the anthraquinone dye decolorization by XL-1 . XL-1 can not decolorize the anthraquinone dye when it is the sole carbon source. Microbial cometabolism and decolorization of the dye take place in the presence of some other carbon source(0.2~0.4g/100ml)called cometabolic substrate. The cometabolic substrate can be peptone, glucose, sodium acetate, beef extract, amylum, etc. The change of molecular structure of the dye before and after decolorized by XL-1 is studied by UV-Vis absorption spectrum. The results indicate that its molecular structure is changed evidently.

  9. Biosorption of Azo dyes by spent Rhizopus arrhizus biomass

    Science.gov (United States)

    Salvi, Neeta A.; Chattopadhyay, S.

    2016-05-01

    In the present study, spent Rhizopus arrhizus biomass was used for the removal of six azo dyes from aqueous solutions. The dye removal capacity of the biomass was evaluated by conducting batch tests as a function of contact time, biomass dosage, pH and initial dye concentrations. The pseudo-second-order kinetic model fitted well with the experimental data with correlation coefficients greater than 0.999, suggesting that chemisorptions might be the rate limiting step. The equilibrium sorption data showed good fit to the Langmuir isotherm model. Among the six dyes tested, the maximum monolayer adsorption capacity for fast red A and metanil yellow was found to be 108.8 and 128.5 mg/g, respectively. These encouraging results suggest that dead Rhizopus arrhizus biomass could be a potential biomaterial for the removal of azo dyes from aqueous dye solution.

  10. Hexagonal microlasers based on organic dyes in nanoporous crystals

    CERN Document Server

    Braun, I; Laeri, F; Nöckel, J U; Schulz-Ekloff, G; Schueth, F; Vietze, U; Weiss, O; Woehrle, D; Braun, Ingo; Ihlein, Guido; Laeri, Franco; Noeckel, Jens U.; Schulz-Ekloff, Guenter; Schueth, Ferdi; Vietze, Uwe; Weiss, Ozlem; Woehrle, Dieter

    2000-01-01

    Molecular sieves, such as nanoporous AlPO_4-5, can host a wide variety of laser active dyes. We embedded pyridine 2 molecules as a representative of a commercially available dye which fits into the channel pores of the host matrix. Many efficient dye molecules, such as rhodamines, do not fit into the pores. But the amount of encapsulated dyes can be increased by modifying the structure of the dyes such that they match the host templates. The resulting microlasers have properties that depend on size and shape of the microresonators, and we discuss a model for microscopic hexagonal ring resonators. In terms of pump needed to reach lasing threshold molecular sieve microlasers are comparable to VCSELs. For dyes which fit into the pores we observed a partial regeneration of photo-induced damage.

  11. —Part I. Interaction of Calcium and Copper-Calcium Alloy with Electrolyte

    Science.gov (United States)

    Zaikov, Yurii P.; Batukhtin, Victor P.; Shurov, Nikolay I.; Ivanovskii, Leonid E.; Suzdaltsev, Andrey V.

    2014-06-01

    This paper describes the interaction between calcium and molten CaCl2 and the solubility of calcium in this melt, depending on the calcium content in the copper-calcium alloy that comes in contact with the molten CaCl2. The negative influence of the dissolved calcium on the current efficiency was verified. The negative effects of moisture and CaO impurities on the calcium current efficiency were demonstrated. The dependence of the current efficiency and the purity of the metal obtained by the electrolysis conditions were studied in a laboratory electrolyzer (20 to 80 A).

  12. Autogenous vein graft thrombosis following exposure to calcium-free solutions (calcium paradox).

    Science.gov (United States)

    Nozick, J H; Farnsworth, P; Montefusco, C M; Parsonnet, V; Ruigrok, T J; Zimmerman, A N

    1981-01-01

    The morphological and functional effects of calcium-free and calcium-containing solutions on canine jugular vein intima were examined under conditions which closely resemble those techniques currently employed in peripheral vascular and aortocoronary bypass surgery. Veins that had been exposed only to calcium-containing solutions remained patent for the duration of the experimental period. Vein perfusion with a calcium-free solution, however, resulted in disruption of the jugular vein intima once calcium ions were reintroduced. Autogenous as a femoral arterial graft became thrombosed within 60 minutes. It is therefore suggested that vein grafts of autogenous origin be irrigated with calcium-containing solutions to prevent intimal damage and thrombosis.

  13. Vitamin D-enhanced duodenal calcium transport.

    Science.gov (United States)

    Wongdee, Kannikar; Charoenphandhu, Narattaphol

    2015-01-01

    For humans and rodents, duodenum is a very important site of calcium absorption since it is exposed to ionized calcium released from dietary complexes by gastric acid. Calcium traverses the duodenal epithelium via both transcellular and paracellular pathways in a vitamin D-dependent manner. After binding to the nuclear vitamin D receptor, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] upregulates the expression of several calcium transporter genes, e.g., TRPV5/6, calbindin-D9k, plasma membrane Ca(2+)-ATPase1b, and NCX1, thereby enhancing the transcellular calcium transport. This action has been reported to be under the regulation of parathyroid-kidney-intestinal and bone-kidney-intestinal axes, in which the plasma calcium and fibroblast growth factor-23 act as negative feedback regulators, respectively. 1,25(OH)2D3 also modulates the expression of tight junction-related genes and convective water flow, presumably to increase the paracellular calcium permeability and solvent drag-induced calcium transport. However, vitamin D-independent calcium absorption does exist and plays an important role in calcium homeostasis under certain conditions, particularly in neonatal period, pregnancy, and lactation as well as in naturally vitamin D-impoverished subterranean mammals.

  14. The Role of Calcium in Osteoporosis

    Science.gov (United States)

    Arnaud, C. D.; Sanchez, S. D.

    1991-01-01

    Calcium requirements may vary throughout the lifespan. During the growth years and up to age 25 to 30, it is important to maximize dietary intake of calcium to maintain positive calcium balance and achieve peak bone mass, thereby possibly decreasing the risk of fracture when bone is subsequently lost. Calcium intake need not be greater than 800 mg/day during the relatively short period of time between the end of bone building and the onset of bone loss (30 to 40 years). Starting at age 40 to 50, both men and women lose bone slowly, but women lose bone more rapidly around the menopause and for about 10 years after. Intestinal calcium absorption and the ability to adapt to low calcium diets are impaired in many postmenopausal women and elderly persons owing to a suspected functional or absolute decrease in the ability of the kidney to produce 1,25(OH)2D2. The bones then become more and more a source of calcium to maintain critical extracellular fluid calcium levels. Excessive dietary intake of protein and fiber may induce significant negative calcium balance and thus increase dietary calcium requirements. Generally, the strongest risk factors for osteoporosis are uncontrollable (e.g., sex, age, and race) or less controllable (e.g., disease and medications). However, several factors such as diet, physical activity, cigarette smoking, and alcohol use are lifestyle related and can be modified to help reduce the risk of osteoporosis.

  15. Calcium channel as a potential anticancer agent.

    Science.gov (United States)

    Kriazhev, L

    2009-11-01

    Anticancer treatment in modern clinical practices includes chemotherapy and radiation therapy with or without surgical interventions. Efficiency of both methods varies greatly depending on cancer types and stages. Besides, chemo- and radiotherapy are toxic and damaging that causes serious side effects. This fact prompts the search for alternative methods of antitumor therapy. It is well known that prolonged or high increase of intracellular calcium concentration inevitably leads to the cell death via apoptosis or necrosis. However, stimulation of cell calcium level by chemical agents is hardly achievable because cells have very sophisticated machinery for maintaining intracellular calcium in physiological ranges. This obstacle can be overridden, nevertheless. It was found that calcium channels in so called calcium cells in land snails are directly regulated by extracellular calcium concentration. The higher the concentration the higher the calcium intake is through the channels. Bearing in mind that extracellular/intracellular calcium concentration ratio in human beings is 10,000-12,000 fold the insertion of the channel into cancer cells would lead to fast and uncontrollable by the cells calcium intake and cell death. Proteins composing the channel may be extracted from plasma membrane of calcium cells and sequenced by mass-spectrometry or N-terminal sequencing. Either proteins or corresponding genes could be used for targeted delivery into cancer cells.

  16. Nano cube of CaSnO3: Facile and green co-precipitation synthesis, characterization and photocatalytic degradation of dye

    Science.gov (United States)

    Moshtaghi, Saeed; Gholamrezaei, Sousan; Salavati Niasari, Masoud

    2017-04-01

    In this work, nanocubes of CaSnO3 have been prepared by a simple and green co-precipitation method. In this technique, for preparation of calcium stannate, we have used from a complex structure of calcium as a new precursor and the synthesis of CaSnO3 have been done in water as a green solvent. Using of complexing precursors were created a congestion in reaction medium. Different conditions have been studied in synthetic approaches and optimized the effect of different parameters on the morphology of product such as precipitation agent (alkaline), pH, temperature, the rate of stirrer, surfactants and the mole ratio of surfactants for preparation product and obtain the best product in terms of quality and morphology. By using of this CaSnO3, two types of azo dyes (acid blue 92 and acid brown 14) have been degraded at presence of ultraviolet light from aqueous solution. Results display that the powder shows appropriate catalytic behavior for degradation of dyes (77% acid brown 14 and 67% acid black 92). Therefore these nano-cube structures have been used as photocatalysts in presence of UV light for degradation of azo dyes.

  17. Auranofin, an Anti-Rheumatic Gold Compound, Modulates Apoptosis by Elevating the Intracellular Calcium Concentration ([Ca{sup 2+}]{sub i}) in MCF-7 Breast Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Varghese, Elizabeth; Büsselberg, Dietrich, E-mail: dib2015@qatar-med.cornell.edu [Weil Cornell Medical College in Qatar, Qatar Foundation-Education City, P.O. Box 24144 Doha (Qatar)

    2014-11-06

    Auranofin, a transition metal complex is used for the treatment of rheumatoid arthritis but is also an effective anti-cancer drug. We investigate the effects of Auranofin in inducing cell death by apoptosis and whether these changes are correlated to changes of intracellular calcium concentration ([Ca{sup 2+}]{sub i}) in breast cancer cells (MCF-7). Cytotoxicity of Auranofin was evaluated using MTS assay and the Trypan blue dye exclusion method. With fluorescent dyes SR-FLICA and 7-AAD apoptotic death and necrotic death were differentiated by Flow cytometry. A concentration dependent decrease in the viability occurred and cells were shifted to the apoptotic phase. Intracellular calcium ([Ca{sup 2+}]{sub i}) was recorded using florescence microscopy and a calcium sensitive dye (Fluo-4 AM) with a strong negative correlation (r = −0.713) to viability. Pharmacological modulators 2-APB (50 μM), Nimodipine (10 μM), Caffeine (10 mM), SKF 96365(20 μM) were used to modify calcium entry and release. Auranofin induced a sustained increase of [Ca{sup 2+}]{sub i} in a concentration and time dependent manner. The use of different blockers of calcium channels did not reveal the source for the rise of [Ca{sup 2+}]{sub i}. Overall, elevation of [Ca{sup 2+}]{sub i} by Auranofin might be crucial for triggering Ca{sup 2+}-dependent apoptotic pathways. Therefore, in anti-cancer therapy, modulating [Ca{sup 2+}]{sub i} should be considered as a crucial factor for the induction of cell death in cancer cells.

  18. Plant waste materials from restaurants as the adsorbents for dyes

    OpenAIRE

    Pavlović Marija D.; Nikolić Ivan R.; Milutinović Milica D.; Dimitrijević-Branković Suzana I.; Šiler-Marinković Slavica S.; Antonović Dušan G.

    2015-01-01

    This paper has demonstrated the valorization of inexpensive and readily available restaurant waste containing most consumed food and beverage residues as adsorbents for methylene blue dye. Coffee, tea, lettuce and citrus waste have been utilized without any pre-treatment, thus the adsorption capacities and dye removal efficiency were determined. Coffee waste showed highest adsorbent capacity, followed by tea, lettuce and citrus waste. The dye removal was mo...

  19. Nature of phosphorescence kinetics of xanthene dyes in biological media

    Science.gov (United States)

    Maryakhina, V. S.

    2016-10-01

    In the paper the experimental results on the nature of the phosphorescence of xanthene dyes in biological media are discussed. Phosphorescence is a monomolecular process and should have exponential type. However, the kinetics of the phosphorescence of xanthene dyes has two-exponential type in biological media. Analysis of data by experimental and theoretical methods showed that the second exponent connects on the phosphorescence of dye dimers. It can be used in biomedical investigation for dose selection of preparation delivery.

  20. NIR Electrofluorochromic Properties of Aza-Boron-dipyrromethene Dyes

    OpenAIRE

    2016-01-01

    The photophysical properties of near-infrared (NIR) emissive aza-boron-dipyrromethene (aza-BDP) dyes incorporating nitrofluorene and alkoxy decorations were intensively investigated. Their highly reversible one-electron reduction process showed characteristic electrofluorochromic (EF) properties in the NIR range, depending on the substituents. The nitrofluorene ethynyl-substituted (Type I) dyes showed smaller EF effects than the alkoxy-containing (Type II) dyes because of the difference in th...

  1. Interaction of Natural Dye (Allium cepa) with Ionic Surfactants

    OpenAIRE

    2013-01-01

    Allium cepa is a natural dye that has been extracted from onion skin with the help of soxhlet apparatus. The pigment in the dye pelargonidin was found to be 2.25%. The interaction of the dye with ionic surfactants, namely, cationic surfactant (cetyltrimethylammonium bromide) and anionic (sodium lauryl sulphate) has been studied by spectrophotometrically, conductivity, and surface tension measurements. The thermodynamic and surface parameters have been evaluated for the interaction process. Th...

  2. Panchromatic Response in Solid-State Dye-Sensitized Solar Cells Containing Phosphorescent Energy Relay Dyes

    KAUST Repository

    Yum, Jun-Ho

    2009-11-23

    Running relay: Incorporating an energyrelay dye (ERD) into the hole transporter of a dye-sensitized solar cell increased power-conversion efficiency by 29% by extending light harvesting into the blue region. In the operating mechanism (see picture), absorption of red photons by the sensitizer transfers an electron into TiO2 and a hole into the electrolyte. Blue photons absorbed by the ERD are transferred by FRET to the sensitizer. Chemical Equitation Presentation © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

  3. Color removal of reactive dyes from water by clinoptilolite.

    Science.gov (United States)

    Armağan, Bülent; Turan, Mustafa; Ozdemir, Orhan; Celik, Mehmet S

    2004-01-01

    The adsorption of reactive dyes on Gordes (Turkey) clinoptilolite was investigated by a series of batch and column adsorption experiments. Three reactive dyes (Everzol Black, Everzol Red, Everzol Yellow) were used in laboratory studies. Synthetic wastewaters were used and the ability of natural zeolite (clinoptilolite) and their modified form were examined. The adsorption results, in batch and column reactor, indicate that natural zeolite have limited adsorption capacities of the reactive dyes but are substantially improved upon modifying their surfaces with quaternary amines (HTAB). The degree of hydrophilicity is found to play an important role in the uptake of reactive dyes.

  4. Primary Photoprocesses in Dyes and Other Complex Molecules.

    Science.gov (United States)

    1978-10-31

    photobiology are given . -~~~~~ 3.2 Reports and Manuscripts in Preparation TR— l3. A Study of the Photodegradation of the Blue—Green Laser Dye , AC3F , A...the contract a preliminary study of the photodegradation of the laser dye , AC3F [Blue—Green Dye Laser Development , Annual Report F4—75 , NELC F233 b...I AD—A0b2 568 WASHINGTON STATE UNIV PULLMAN DEPT OF CHEMISTRY FFG 713 ‘c — F, PRIMARY PHOTOPROCESSES IN DYES AND OTHER COMPLEX MOLECULES. (U) OCT 78

  5. Dye-sensitized solar cells based on purple corn sensitizers

    Science.gov (United States)

    Phinjaturus, Kawin; Maiaugree, Wasan; Suriharn, Bhalang; Pimanpaeng, Samuk; Amornkitbamrung, Vittaya; Swatsitang, Ekaphan

    2016-09-01

    Natural dye extracted from husk, cob and silk of purple corn, were used for the first time as photosensitizers in dye sensitized solar cells (DSSCs). The dye sensitized solar cells fabrication process has been optimized in terms of solvent extraction. The resulting maximal efficiency of 1.06% was obtained from purple corn husk extracted by acetone. The ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS) and incident photon-to-current efficiency (IPCE) were employed to characterize the natural dye and the DSSCs.

  6. Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

    Directory of Open Access Journals (Sweden)

    Bo Wei

    2013-01-01

    Full Text Available There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes was the fastest for silk and the slowest for wool. The activation energies for the adsorption process on wool, silk, and nylon were found to be 107.15, 87.85, and 45.31 kJ/mol, respectively. The adsorption of lac dyes on the three fibers followed the Langmuir mechanism, indicating that the electrostatic interactions between lac dyes and those fibers occurred. The saturation values for lac adsorption on the three fibers decreased in the order of wool > silk > nylon; the Langmuir affinity constant of lac adsorption on nylon was much higher than those on wool and silk.

  7. 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.

  8. Mutagenicity assessment of textile dyes from Sanganer (Rajasthan).

    Science.gov (United States)

    Mathur, Nupur; Bhatnagar, Pradeep

    2007-01-01

    Sanganer town, district Jaipur (Rajasthan, India) is famous worldwide for its hand block dyeing and textile printing industries. These industries use a variety of chemicals and dyes during processing and finishing of raw materials. Most of the textile dyes used by these industries have not been evaluated for their impact on health and the environment. The workers in these industries are exposed to such dyes with no control over the length and frequency of exposure. Further, untreated and sometimes even treated effluents from these industries are released into surface waters of Amani Shah drainage or through the drainage systems, seep into the ground water and adjoining water bodies. Since many textile dyes are known carcinogens and mutagens, a complete evaluation of the safety of these dyes in the human environment must include an evaluation of their genotoxicity or mutagenicity. A total of 12 textile dyes from Sanganer were tested for their mutagenicity, by Ames Salmonella reversion assay using strain TA 100 of Salmonella typhimurium. Only 1 dye, Red 12 B showed absence of mutagenic activity. The remaining 11 dyes were all positively mutagenic.

  9. 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.

  10. Effects of heat treatment on the dye adsorption of ZnO nanorods for dye-sensitized solar cells

    Science.gov (United States)

    Yun, Won Suk; Choi, Seok Cheol; Sohn, Sang Ho; Oh, Sang Jin

    2012-11-01

    Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the heat-treatment effects on the dye adsorption in the DSSCs were studied. The heat treatment of well-aligned ZnO nanorods was performed at 200 ˜ 500 °C for 1 h, which was immediately followed by the dye adsorption. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Vis absorbance by using Beer-Lambert's law. The efficiency of the DSSCs with ZnO nanorods was measured to investigate the heat-treatment effects of ZnO nanorods on the dye adsorption properties. The heat-treatment of ZnO nanorods was found to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

  11. Effects of heat treatment on the dye adsorption of ZnO nanorods for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Won Suk; Choi, Seok Cheol; Sohn, Sang Ho [Kyungpook National University, Daegu (Korea, Republic of); Oh, Sang Jin [Phoenix Materials, Gumi (Korea, Republic of)

    2012-11-15

    Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the heat-treatment effects on the dye adsorption in the DSSCs were studied. The heat treatment of well-aligned ZnO nanorods was performed at 200 ∼ 500 .deg. C for 1 h, which was immediately followed by the dye adsorption. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Vis absorbance by using Beer-Lambert's law. The efficiency of the DSSCs with ZnO nanorods was measured to investigate the heat-treatment effects of ZnO nanorods on the dye adsorption properties. The heat-treatment of ZnO nanorods was found to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

  12. Preparation of Nanoporous TiO2 for Dye-Sensitized Solar Cell (DSSC) Using Various Dyes

    Science.gov (United States)

    Yuliarto, Brian; Fanani, Fahiem; Fuadi, M. Kasyful; Nugraha

    2010-10-01

    This article reports the development of organic dyes as an attempt to reduce material costs of Dye-Sensitized Solar Cell (DSSC). Indonesia, a country with variety and considerable number of botanical resources, is suitable to perform the research. Indonesian black rice, curcuma, papaya leaf, and the combination were chosen as organic dyes source. Dyes were extracted using organic solvent and adsorbed on mesoporous Titanium Dioxide (TiO2) which has been optimized in our laboratory. The best dyes light absorbance and performance obtained from papaya leaf as chlorophyll dyes that gives two peaks at 432 nm and 664 nm from UV-Vis Spectrophotometry and performance under 100 mW/cm2 Xenon light solar simulator gives VOC = 0.566 Volt, JSC = 0.24 mA/cm2, Fill Factor = 0.33, and efficiency of energy conversion 0,045%.

  13. Effect of Substituents in Catechol Dye Sensitizers on Photovoltaic Performance of Type II Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Ooyama, Yousuke; Kanda, Masahiro; Uenaka, Koji; Ohshita, Joji

    2015-10-01

    In order to provide a direction in molecular design of catechol (Cat) dyes for type II dye-sensitized solar cells (DSSCs), the dye-to-TiO2 charge-transfer (DTCT) characteristics of Cat dyes with various substituents and their photovoltaic performance in DSSCs are investigated. The Cat dyes with electron-donating or moderately electron-withdrawing substituents exhibit a broad absorption band corresponding to DTCT upon binding to TiO2 films, whereas those with strongly electron-withdrawing substituents exhibit weak DTCT. This study indicates that the introduction of a moderately electron-withdrawing substituent on the Cat moiety leads to not only an increase in the DTCT efficiency, but also the retardation of back electron transfer. This results in favorable conditions for the type II electron-injection pathway from the ground state of the Cat dye to the conduction band of the TiO2 electrode by the photoexcitation of DTCT bands.

  14. Calcium signals can freely cross the nuclear envelope in hippocampal neurons: somatic calcium increases generate nuclear calcium transients

    Directory of Open Access Journals (Sweden)

    Bading Hilmar

    2007-07-01

    Full Text Available Abstract Background In hippocampal neurons, nuclear calcium signaling is important for learning- and neuronal survival-associated gene expression. However, it is unknown whether calcium signals generated by neuronal activity at the cell membrane and propagated to the soma can unrestrictedly cross the nuclear envelope to invade the nucleus. The nuclear envelope, which allows ion transit via the nuclear pore complex, may represent a barrier for calcium and has been suggested to insulate the nucleus from activity-induced cytoplasmic calcium transients in some cell types. Results Using laser-assisted uncaging of caged calcium compounds in defined sub-cellular domains, we show here that the nuclear compartment border does not represent a barrier for calcium signals in hippocampal neurons. Although passive diffusion of molecules between the cytosol and the nucleoplasm may be modulated through changes in conformational state of the nuclear pore complex, we found no evidence for a gating mechanism for calcium movement across the nuclear border. Conclusion Thus, the nuclear envelope does not spatially restrict calcium transients to the somatic cytosol but allows calcium signals to freely enter the cell nucleus to trigger genomic events.

  15. Fortification of all-purpose wheat-flour tortillas with calcium lactate, calcium carbonate, or calcium citrate is acceptable.

    Science.gov (United States)

    Romanchik-Cerpovicz, Joelle E; McKemie, Rebecca J

    2007-03-01

    Fortification helps provide adequate nutrients for individuals not meeting daily needs. Foods may be fortified with calcium to assist individuals with lactose intolerance and others preferring not to consume traditional forms of dairy. This study examined the quality of all-purpose wheat-flour tortillas fortified with calcium lactate, calcium carbonate, or calcium citrate. These tortillas were compared to similarly prepared nonfortified flour tortillas (control) and commercial nonfortified flour tortillas. Calcium-fortified tortillas contained 114 mg elemental calcium per standard serving (48 g tortilla), an 8.6-fold increase compared to nonfortified tortillas. Moisture contents and rollabilities of all tortillas were similar. Consumers (N=87) evaluated each tortilla in duplicate using a hedonic scale and reported liking the appearance, texture, flavor, aftertaste, and overall acceptability of all tortillas. However, the appearance of control tortillas was preferred over commercial tortillas (P<0.01), whereas the aftertaste of commercial tortillas or those fortified with calcium carbonate was preferred over the control (P<0.05). Despite these differences, consumers were equally willing to purchase both fortified and nonfortified tortillas, suggesting that appearance and aftertaste may not influence willingness to purchase. Overall, this study shows that fortification of flour tortillas with various forms of calcium is a feasible alternative calcium source.

  16. Calcium Impact on Milk Gels Formation

    DEFF Research Database (Denmark)

    Koutina, Glykeria

    and dense gel structure and with little seperation of whey due to participation of calcium to the final gel structure. On the other hand, the combination of heat treatment and calcium addition to milk with pH values lower than 5.6 will still produce gel structures which are dominated by the decrease of p......Calcium is one of the several elements that can be found in milk distributed between the micellar and the serum milk phase. Calcium is important from a nutritional point of view, but its contribution to the functional and structural properties of dairy products has only recently been...... acknowledgement. The presence of calcium in a dynamic equilibrium between the serum and the micellar milk phase make the distribution susceptible to certain physicochemical conditions and to technological treatments of milk resulting in fluctuations in pH and temperature and also sensitive to addition of calcium...

  17. Altered calcium signaling in cancer cells.

    Science.gov (United States)

    Stewart, Teneale A; Yapa, Kunsala T D S; Monteith, Gregory R

    2015-10-01

    It is the nature of the calcium signal, as determined by the coordinated activity of a suite of calcium channels, pumps, exchangers and binding proteins that ultimately guides a cell's fate. Deregulation of the calcium signal is often deleterious and has been linked to each of the 'cancer hallmarks'. Despite this, we do not yet have a full understanding of the remodeling of the calcium signal associated with cancer. Such an understanding could aid in guiding the development of therapies specifically targeting altered calcium signaling in cancer cells during tumorigenic progression. Findings from some of the studies that have assessed the remodeling of the calcium signal associated with tumorigenesis and/or processes important in invasion and metastasis are presented in this review. The potential of new methodologies is also discussed. This article is part of a Special Issue entitled: Membrane channels and transporters in cancers.

  18. Development of a homogeneous calcium mobilization assay for high throughput screening of mas-related gene receptor agonists

    Institute of Scientific and Technical Information of China (English)

    Rui ZHANG; Pang-ke YAN; Cai-hong ZHOU; Jia-yu LIAO; Ming-wei WANG

    2007-01-01

    Aim: To develop homogeneous calcium mobilization assay for high-throughput screening (HTS) of mas-related gene (Mrg) receptor agonists. Methods: CHO-K1 cells stably expressing the full-length MrgD receptor and a calcium-sensitive dye were used to develop an HTS assay based on intracellular calcium influx. This method was applied to large-scale screening of a library containing 8000 synthetic compounds and natural product extracts, cAMP measurements were camed out to verify the bioactivities of the hits found by the calcium mobilization assay. Similar approaches were also employed in the identification of the MrgA1 recep-tor agonists following HTS of 16 000 samples. Results: EC50 values of the positive control compounds (β-alanine for MrgD receptor and dynorphin A for MrgA1 receptor) determined by the calcium mobilization assay were consistent with those reported in the literature, and the Z' factors were 0.65 and 0.50 for MrgD and MrgA1 receptor assay, respectively. About 31 compounds for the MrgD receptor and 48 compounds for the MrgA1 receptor showing ≥20% of the maximal agonist activities found in the controls were initially identified as hits. Secondary screen- ing confirmed that 2 compounds for each receptor possessed specific agonist activities. Intracellular cAMP level measurements indicated that the 2 confirmed hits displayed the functionality of the MrgD receptor agonists. Conclusion: A series of validation studies demonstrated that the homogeneous calcium mobili-zation assay developed was highly efficient, amenable to automation and a robust tool to screen potential MrgD and MrgA1 receptor agonists. Its application may be expanded to other G-protein coupled receptors that mobilize calcium influx upon activation.

  19. Overbased Calcium sulfonate Detergent Technology Overview

    Institute of Scientific and Technical Information of China (English)

    MA Qing-gao; MUIR Ronald J.

    2009-01-01

    Overbased calcium sulfonate is used widely as detergent in automotive and marine lubricants, as well as various industrial oil applications. In this paper, the process to produce overbased calcium sulfonate is overviewed. The sulfonate structure and molecular weight and its molecular weight distribution, the enclosed calcium carbonate nanoparticle size and crystalline structure, properties of the carrier oil, all influence its properties, such as stability, viscosity, and detergency of the system.

  20. [Calcium carbide of different crystal formation synthesized by calcium carbide residue].

    Science.gov (United States)

    Lu, Zhong-yuan; Kang, Ming; Jiang, Cai-rong; Tu, Ming-jing

    2006-04-01

    To recycle calcium carbide residue effectively, calcium carbide of different crystal form, including global aragonite, calcite and acicular calcium carbide was synthesized. Both the influence of pretreatment in the purity of calcium carbide, and the influence of temperatures of carbonization reaction, release velocity of carbon dioxide in the apparition of calcium carbide of different crystal form were studied with DTA-TG and SEM. The result shows that calcium carbide residue can take place chemistry reaction with ammonia chlorinate straight. Under the condition that pH was above 7, the purity of calcium carbide was above 97%, and the whiteness was above 98. Once provided the different temperatures of carbonization reaction and the proper release velocity of carbon dioxide, global aragonite, calcite and acicular calcium carbide were obtained.

  1. 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.

  2. 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.

  3. Database of two-dimensional polyacrylamide gel electrophoresis of proteins labeled with CyDye DIGE Fluor saturation dye.

    Science.gov (United States)

    Fujii, Kazuyasu; Kondo, Tadashi; Yokoo, Hideki; Okano, Tetsuya; Yamada, Masayo; Yamada, Tesshi; Iwatsuki, Keiji; Hirohashi, Setsuo

    2006-03-01

    CyDye DIGE Fluor saturation dye (saturation dye, GE Healthcare Amersham Biosciences) enables highly sensitive 2-D PAGE. As the dye reacts with all reduced cysteine thiols, 2-D PAGE can be performed with a lower amount of protein, compared with CyDye DIGE Fluor minimal dye (GE Healthcare Amersham Biosciences), the sensitivity of which is equivalent to that of silver staining. We constructed a 2-D map of the saturation dye-labeled proteins of a liver cancer cell line (HepG2) and identified by MS 92 proteins corresponding to 123 protein spots. Functional classification revealed that the identified proteins had chaperone, protein binding, nucleotide binding, metal ion binding, isomerase activity, and motor activity. The functional distribution and the cysteine contents of the proteins were similar to those in the most comprehensive 2-D database of hepatoma cells (Seow et al.., Electrophoresis 2000, 21, 1787-1813), where silver staining was used for protein visualization. Hierarchical clustering on the basis of the quantitative expression profiles of the 123 characterized spots labeled with two charge- and mass-matched saturation dyes (Cy3 and Cy5) discriminated between nine hepatocellular carcinoma cell lines and primary cultured hepatocytes from five individuals, suggesting the utility of saturation dye and our database for proteomic studies of liver cancer.

  4. Osteoblasts detect pericellular calcium concentration increase via neomycin-sensitive voltage gated calcium channels.

    Science.gov (United States)

    Sun, Xuanhao; Kishore, Vipuil; Fites, Kateri; Akkus, Ozan

    2012-11-01

    The mechanisms underlying the detection of critically loaded or micro-damaged regions of bone by bone cells are still a matter of debate. Our previous studies showed that calcium efflux originates from pre-failure regions of bone matrix and MC3T3-E1 osteoblasts respond to such efflux by an increase in the intracellular calcium concentration. The mechanisms by which the intracellular calcium concentration increases in response to an increase in the pericellular calcium concentration are unknown. Elevation of the intracellular calcium may occur via release from the internal calcium stores of the cell and/or via the membrane bound channels. The current study applied a wide range of pharmaceutical inhibitors to identify the calcium entry pathways involved in the process: internal calcium release from endoplasmic reticulum (ER, inhibited by thapsigargin and TMB-8), calcium receptor (CaSR, inhibited by calhex), stretch-activated calcium channel (SACC, inhibited by gadolinium), voltage-gated calcium channels (VGCC, inhibited by nifedipine, verapamil, neomycin, and ω-conotoxin), and calcium-induced-calcium-release channel (CICRC, inhibited by ryanodine and dantrolene). These inhibitors were screened for their effectiveness to block intracellular calcium increase by using a concentration gradient induced calcium efflux model which mimics calcium diffusion from the basal aspect of cells. The inhibitor(s) which reduced the intracellular calcium response was further tested on osteoblasts seeded on mechanically loaded notched cortical bone wafers undergoing damage. The results showed that only neomycin reduced the intracellular calcium response in osteoblasts, by 27%, upon extracellular calcium stimulus induced by concentration gradient. The inhibitory effect of neomycin was more pronounced (75% reduction in maximum fluorescence) for osteoblasts seeded on notched cortical bone wafers loaded mechanically to damaging load levels. These results imply that the increase in

  5. Laser-induced fluorescence and optical reflection spectra of Japanese natural dyes on silk

    OpenAIRE

    Miyoshi, Tadaki; Matsuda, Yasunori

    1987-01-01

    Fluorescence spectra under nitrogen-laser excitation were measured for silk cloth dyed with Japanese natural dyes. An identification of the dyes on silk was carried out using a laser-induced fluorescence (LIF) technique since dyed cloth has a characteristic fluorescence spectra. Moreover, it is possible to identify dyes on faded cloth and on cloth prepared by a combination dyeing using two kinds of dyes. The LIF technique can identify dyes on cloth which is difficult to identify using the ref...

  6. Calcium binding proteins and calcium signaling in prokaryotes.

    Science.gov (United States)

    Domínguez, Delfina C; Guragain, Manita; Patrauchan, Marianna

    2015-03-01

    With the continued increase of genomic information and computational analyses during the recent years, the number of newly discovered calcium binding proteins (CaBPs) in prokaryotic organisms has increased dramatically. These proteins contain sequences that closely resemble a variety of eukaryotic calcium (Ca(2+)) binding motifs including the canonical and pseudo EF-hand motifs, Ca(2+)-binding β-roll, Greek key motif and a novel putative Ca(2+)-binding domain, called the Big domain. Prokaryotic CaBPs have been implicated in diverse cellular activities such as division, development, motility, homeostasis, stress response, secretion, transport, signaling and host-pathogen interactions. However, the majority of these proteins are hypothetical, and only few of them have been studied functionally. The finding of many diverse CaBPs in prokaryotic genomes opens an exciting area of research to explore and define the role of Ca(2+) in organisms other than eukaryotes. This review presents the most recent developments in the field of CaBPs and novel advancements in the role of Ca(2+) in prokaryotes.

  7. Daylight-driven photocatalytic degradation of ionic dyes with negatively surface-charged In2S3 nanoflowers: dye charge-dependent roles of reactive species

    Science.gov (United States)

    Ge, Suxiang; Cai, Lejuan; Li, Dapeng; Fa, Wenjun; Zhang, Yange; Zheng, Zhi

    2015-12-01

    Even though dye degradation is a successful application of semiconductor photocatalysis, the roles of reactive species in dye degradation have not received adequate attention. In this study, we systematically investigated the degradation of two cationic dyes (rhodamine B and methylene blue) and two anionic dyes (methyl orange and orange G) over negatively surface-charged In2S3 nanoflowers synthesized at 80 °C under indoor daylight lamp irradiation. It is notable to find In2S3 nanoflowers were more stable in anionic dyes degradation compared to that in cationic dyes removal. The active species trapping experiments indicated photogenerated electrons were mainly responsible for cationic dyes degradation, but holes were more important in anionic dyes degradation. A surface-charge-dependent role of reactive species in ionic dye degradation was proposed for revealing such interesting phenomenon. This study would provide a new insight for preparing highly efficient daylight-driven photocatalyst for ionic dyes degradation.

  8. Disease causing mutations of calcium channels.

    Science.gov (United States)

    Lorenzon, Nancy M; Beam, Kurt G

    2008-01-01

    Calcium ions play an important role in the electrical excitability of nerve and muscle, as well as serving as a critical second messenger for diverse cellular functions. As a result, mutations of genes encoding calcium channels may have subtle affects on channel function yet strongly perturb cellular behavior. This review discusses the effects of calcium channel mutations on channel function, the pathological consequences for cellular physiology, and possible links between altered channel function and disease. Many cellular functions are directly or indirectly regulated by the free cytosolic calcium concentration. Thus, calcium levels must be very tightly regulated in time and space. Intracellular calcium ions are essential second messengers and play a role in many functions including, action potential generation, neurotransmitter and hormone release, muscle contraction, neurite outgrowth, synaptogenesis, calcium-dependent gene expression, synaptic plasticity and cell death. Calcium ions that control cell activity can be supplied to the cell cytosol from two major sources: the extracellular space or intracellular stores. Voltage-gated and ligand-gated channels are the primary way in which Ca(2+) ions enter from the extracellular space. The sarcoplasm reticulum (SR) in muscle and the endoplasmic reticulum in non-muscle cells are the main intracellular Ca(2+) stores: the ryanodine receptor (RyR) and inositol-triphosphate receptor channels are the major contributors of calcium release from internal stores.

  9. Regulation of cardiomyocyte autophagy by calcium.

    Science.gov (United States)

    Shaikh, Soni; Troncoso, Rodrigo; Criollo, Alfredo; Bravo-Sagua, Roberto; García, Lorena; Morselli, Eugenia; Cifuentes, Mariana; Quest, Andrew F G; Hill, Joseph A; Lavandero, Sergio

    2016-04-15

    Calcium signaling plays a crucial role in a multitude of events within the cardiomyocyte, including cell cycle control, growth, apoptosis, and autophagy. With respect to calcium-dependent regulation of autophagy, ion channels and exchangers, receptors, and intracellular mediators play fundamental roles. In this review, we discuss calcium-dependent regulation of cardiomyocyte autophagy, a lysosomal mechanism that is often cytoprotective, serving to defend against disease-related stress and nutrient insufficiency. We also highlight the importance of the subcellular distribution of calcium and related proteins, interorganelle communication, and other key signaling events that govern cardiomyocyte autophagy.

  10. Altered calcium signaling following traumatic brain injury

    Directory of Open Access Journals (Sweden)

    John Thomas Weber

    2012-04-01

    Full Text Available Cell death and dysfunction after traumatic brain injury (TBI is caused by a primary phase, related to direct mechanical disruption of the brain, and a secondary phase which consists of delayed events initiated at the time of the physical insult. Arguably, the calcium ion contributes greatly to the delayed cell damage and death after TBI. A large, sustained influx of calcium into cells can initiate cell death signaling cascades, through activation of several degradative enzymes, such as proteases and endonucleases. However, a sustained level of intracellular free calcium is not necessarily lethal, but the specific route of calcium entry may couple calcium directly to cell death pathways. Other sources of calcium, such as intracellular calcium stores, can also contribute to cell damage. In addition, calcium-mediated signal transduction pathways in neurons may be perturbed following injury. These latter types of alterations may contribute to abnormal physiology in neurons that do not necessarily die after a traumatic episode. This review provides an overview of experimental evidence that has led to our current understanding of the role of calcium signaling in death and dysfunction following TBI.

  11. Sintering of calcium phosphate bioceramics.

    Science.gov (United States)

    Champion, E

    2013-04-01

    Calcium phosphate ceramics have become of prime importance for biological applications in the field of bone tissue engineering. This paper reviews the sintering behaviour of these bioceramics. Conventional pressureless sintering of hydroxyapatite, Ca10(PO4)6(OH)2, a reference compound, has been extensively studied. Its physico-chemistry is detailed. It can be seen as a competition between two thermally activated phenomena that proceed by solid-state diffusion of matter: densification and grain growth. Usually, the objective is to promote the first and prevent the second. Literature data are analysed from sintering maps (i.e. grain growth vs. densification). Sintering trajectories of hydroxyapatite produced by conventional pressureless sintering and non-conventional techniques, including two-step sintering, liquid phase sintering, hot pressing, hot isostatic pressing, ultrahigh pressure, microwave and spark plasma sintering, are presented. Whatever the sintering technique may be, grain growth occurs mainly during the last step of sintering, when the relative bulk density reaches 95% of the maximum value. Though often considered very advantageous, most assisted sintering techniques do not appear very superior to conventional pressureless sintering. Sintering of tricalcium phosphate or biphasic calcium phosphates is also discussed. The chemical composition of calcium phosphate influences the behaviour. Similarly, ionic substitutions in hydroxyapatite or in tricalcium phosphate create lattice defects that modify the sintering rate. Depending on their nature, they can either accelerate or slow down the sintering rate. The thermal stability of compounds at the sintering temperature must also be taken into account. Controlled atmospheres may be required to prevent thermal decomposition, and flash sintering techniques, which allow consolidation at low temperature, can be helpful.

  12. Heart failure drug digitoxin induces calcium uptake into cells by forming transmembrane calcium channels

    OpenAIRE

    2008-01-01

    Digitoxin and other cardiac glycosides are important, centuries-old drugs for treating congestive heart failure. However, the mechanism of action of these compounds is still being elucidated. Calcium is known to potentiate the toxicity of these drugs, and we have hypothesized that digitoxin might mediate calcium entry into cells. We report here that digitoxin molecules mediate calcium entry into intact cells. Multimers of digitoxin molecules also are able to form calcium channels in pure plan...

  13. The Role of Calcium in Prevention and Treatment of Osteoporosis.

    Science.gov (United States)

    Heaney, Robert P.

    1987-01-01

    Osteoporosis results from several factors. Calcium deficiency is only one, and high calcium intake will prevent only those cases in which calcium is the limiting factor. Calcium cannot reverse, but only arrest, bone loss. A high calcium intake for every member of the population is advocated. (Author/MT)

  14. 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.

  15. Textile dye degradation using nano zero valent iron: A review.

    Science.gov (United States)

    Raman, Chandra Devi; Kanmani, S

    2016-07-15

    Water soluble unfixed dyes and inorganic salts are the major pollutants in textile dyeing industry wastewater. Existing treatment methods fail to degrade textile dyes and have limitations too. The inadequate treatment of textile dyeing wastewater is a major concern when effluent is directly discharged into the nearby environment. Long term disposal threatens the environment, which needs reclamation. This article reviews the current knowledge of nano zero valent iron (nZVI) technique in the degradation of textile dyes. The application of nZVI on textile dye degradation is receiving great attention in the recent years because nZVI particles are highly reactive towards the pollutant, less toxic, and economical. The nZVI particles aggregate quickly with respect to time and the addition of supports such as resin, nickel, zinc, bentonite, biopolymer, kaolin, rectorite, nickel-montmorillonite, bamboo, cellulose, biochar, graphene, and clinoptilolite enhanced the stability of iron nanoparticles. Inclusion of supports may in turn introduce additional toxic pollutants, hence green supports are recommended. The majority of investigations concluded dye color removal as textile dye compound removal, which is not factual. Very few studies monitored the removal of total organic carbon and observed the products formed. The results revealed that partial mineralization of the textile dye compound was achieved. Instead of stand alone technique, nZVI can be integrated with other suitable technique to achieve complete degradation of textile dye and also to treat multiple pollutants in the real textile dyeing wastewater. It is highly recommended to perform more bench-scale and pilot-scale studies to apply this technique to the textile effluent contaminated sites.

  16. Calcium imaging perspectives in plants.

    Science.gov (United States)

    Kanchiswamy, Chidananda Nagamangala; Malnoy, Mickael; Occhipinti, Andrea; Maffei, Massimo E

    2014-03-04

    The calcium ion (Ca2+) is a versatile intracellular messenger. It provides dynamic regulation of a vast array of gene transcriptions, protein kinases, transcription factors and other complex downstream signaling cascades. For the past six decades, intracellular Ca2+ concentration has been significantly studied and still many studies are under way. Our understanding of Ca2+ signaling and the corresponding physiological phenomenon is growing exponentially. Here we focus on the improvements made in the development of probes used for Ca2+ imaging and expanding the application of Ca2+ imaging in plant science research.

  17. The Electronic Structure of Calcium

    DEFF Research Database (Denmark)

    Jan, J.-P.; Skriver, Hans Lomholt

    1981-01-01

    The electronic structure of calcium under pressure is re-examined by means of self-consistent energy band calculations based on the local density approximation and using the linear muffin-tin orbitals (LMTO) method with corrections to the atomic sphere approximation included. At zero pressure.......149 Ryd, respectively, relative to the s band, give the best possible agreement. Under increasing pressure the s and p electrons are found to transfer into the d band, and Ca undergoes metal-semimetal-metal electronic transitions. Calculations of the bandstructure and the electronic pressure, including...

  18. Dye Oriza sativa glutinosa doped Fe as a active element of Dye Sensitized Solar Cell (DSSC)

    Science.gov (United States)

    Prasada, A. B.; Fadli, U. M.; Cari; Supriyanto, A.

    2016-11-01

    The aims of the research are to determine the effect of doping Fe (III) Sulphate into dye Oriza sativa glutinosa on the characteristics parameters of solar cells, to determine the optical characteristic, functional group and electrical characteristic of dye Oriza sativa glutinosa doped Fe (III) sulphate. TiO2 nano size as much as 0.5 gr dissolved in 3 ml ethanol. 100 gr black sticky rice (Oriza sativa glutinosa) was immersed in 80 ml ethanol solution (95%) and kept at room temperature without exposing to light. Then it was filtered with a filter paper no.42, and the extracted result was process with chromatography. Furthermore, it was doped with Fe (III) sulphate respectively of 10-1 M, 10-2 M, 10-3 M. The characteristic of dye solution was measured using UV-Visible Spectrophotometer Lambda 25 for absorbance, Elkahfi 100/I-V meter for conductivity amd Keithey 2602A for characterization of current and voltage (I-V). The result showed that the area of dye Oriza sativa glutionosa doped Fe (III) sulphate with concentration 10-1 M the largest, because the value of Voc intercept at 6.40 × 10-1 mV and the value Isc intercept at 1.89 × 10-3 mA, with efficiency value is 0.148%.

  19. A new technology for harnessing the dye polluted water and dye collection in the chemical factory

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new technology for harnessing the dye polluted water and dyecollection was developed. It is based on the enhanced evaporation by using solar, wind, and air temperature energy and additional heat-electric energy. It consists of four parts: (1) evaporation carrier system (evaporation carrier and frame for evaporation carrier) for polluted water; (2) polluted water circulating system (pumping-spraying-collecting); (3) heating system; (4) workshop with polluted water reservoir-tanks and rainfall prevention roof. The polluted water was (heated in case necessary) sprayed to the evaporation carrier system and the water was evaporated when it moved in the space and downward along the carrier mainly by using natural (solar, wind, and air temperature energy). In case, when there is no roof for the carrier system, thepolluted water can be stored in the reservoirs (storage volume for about 20 days). The first 10-25 mm rainfall also need to be stored in the reservoirs to meet the state standard for discharging wastewater. The dye may be collected at the surface in the reservoir-tanks and the crystallized salt may be collected at the bottom plate. The black-color wastewater released by the factory is no more discharged to the surface water system of Taihu Lake Basin. About 2 kg dye and 200 kg industrial salt may be collected from each tone of the polluted water. The non-pollution production of dye may be realized by using this technology with environmental, economical and social benefits.

  20. Fabrication and analysis of dye-sensitized solar cell using natural dye extracted from dragon fruit

    Directory of Open Access Journals (Sweden)

    Riyaz Ahmad Mohamed Ali

    2010-12-01

    Full Text Available Dragon fruit dye has been prepared and used in the fabrication of DSSC as sensitizer. The properties of dragon fruit dye have been investigated by UV-Vis and FTIR technique. The absorption spectrum shows a peak value of 535 nm. Chemically dragon fruit dye shows present of intermolecular H-bond, conjugate C=O stretching and esters acetates C-O-C stretching vibration, which is due to the component of anthocyanin. On the other hand, the resistivity of TiO2 film on ITO glass before it is used for the fabrication of DSSC is also investigated. The TiO2 sheet resistivity increase from 1 layer = 22.1 Ω cm to 2 layers = 369.6 Ω cm. Finally, the efficiency of assemble DSSC was evaluated and simulated using a custom made technique. The result shows fill factor, Pmax and efficiency during the present of halogen lamp are 0.30, 13 μW, 0.22%, respectively. We have successfully showed that the DSSC using dragon fruit as a dye sensitizer is useful for the preparation of environmental friendly and low-cost DSSC.

  1. Synthesis of dye linked conducting block copolymers, dye linked conducting homopolymers and preliminary application to photovoltaics

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Hagemann, O.; Jørgensen, M.

    2004-01-01

    A synthetic approach to the synthesis of a large super molecule composed of two chemically different conducting polymer blocks with, respectively, high and low lying electronic energy levels linked through a porphyrin dye molecule is presented. The synthetic strategies to these molecular...

  2. Biosorption and biodegradation of a sulfur dye in high-strength dyeing wastewater by Acidithiobacillus thiooxidans.

    Science.gov (United States)

    Nguyen, Thai Anh; Fu, Chun-Chieh; Juang, Ruey-Shin

    2016-11-01

    The ability of the bacterial strain Acidithiobacillus thiooxidans to remove sulfur blue 15 (SB15) dye from water samples was examined. This bacterium could not only oxidize sulfur compounds to sulfuric acid but also promote the attachment of the cells to the surface of sulfidic particles, therefore serving as an efficient biosorbent. The biosorption isotherms were better described by the Langmuir equation than by the Freundlich or Dubinin-Radushkevich equation. Also, the biosorption process followed the pseudo-second-order kinetics. At pH 8.3 and SB15 concentrations up to 2000 mg L(-1) in the biomass/mineral salt solution, the dye removal and decolorization were 87.5% and 91.4%, respectively, following the biosorption process. Biodegradation was proposed as a subsequent process for the remaining dye (250-350 mg L(-1)). A central composite design was used to analyze independent variables in the response surface methodology study. Under the optimal conditions (i.e., initial dye concentration of 300 mg L(-1), initial biomass concentration of 1.0 g L(-1), initial pH of 11.7, and yeast extract dose of 60 mg L(-1)), up to 50% of SB15 was removed after 4 days of biodegradation.

  3. Difference gel electrophoresis (DIGE) using CyDye DIGE fluor minimal dyes.

    Science.gov (United States)

    Chakravarti, Bulbul; Gallagher, Sean R; Chakravarti, Deb N

    2005-02-01

    One- and two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1- and 2-D SDS-PAGE) have been widely used for the separation and quantitative estimation of proteins. Following electrophoresis, the gels are stained appropriately to visualize the proteins. Difference gel electrophoresis (DIGE) is a new technique in which different protein samples, individually labeled with specific CyDyes, are combined together followed by electrophoresis and post electrophoretic co-detection and co-analysis on the same gel. CyDye DIGE fluor minimal dyes, which consist of three different CyDyes with different spectral characteristics, have been widely used for such purposes. The technique is highly sensitive with a wide dynamic range for detection of proteins and compatible with state-of-the-art protein identification techniques using mass spectrometry. Although DIGE is mainly used to compare differential expression of various protein samples using 2-D SDS-PAGE, 1-D DIGE also has important applications in quantitative proteomic studies.

  4. Co-sensitization of natural dyes for improved efficiency in dye-sensitized solar cell application

    Science.gov (United States)

    Kumar, K. Ashok; Subalakshmi, K.; Senthilselvan, J.

    2016-05-01

    In this paper, a new approach of co-sensitized DSSC based on natural dyes is investigated to explore the possible way to improve the power conversion efficiency. To realize this purpose 10 DSSC devices were fabricated using mono-sensitization and co-sensitization of ethanolic extracts of natural dye sensitizers obtained from Cactus fruit, Jambolana fruit, Curcumin and Bermuda grass. The optical absorption spectrum of the mono and hybrid dye extracts were studied by UV-Visible absorption spectrum. It shows the characteristic absorption peaks in visible region corresponds to the presence of natural pigments of anthocyanin, betacyanin and chlorophylls. Absorption spectrum of hybrid dyes reveals a wide absorption band in visible region with improved extinction co-efficient and it is favorable for increased light harvesting nature. The power conversion efficiency of DSSC devices were calculated using J-V curve and the maximum efficiency achieved in the present work is noted to be ~0.61% for Cactus-Bermuda co-sensitized DSSC.

  5. Calcium

    Science.gov (United States)

    ... don't have enough of the intestinal enzyme lactase that helps digest the sugar (lactose) in dairy ... free dairy products are readily available, as are lactase drops that can be added to dairy products ...

  6. Calcium

    Science.gov (United States)

    ... tingling in the fingers, convulsions, and abnormal heart rhythms that can lead to death if not corrected. ... that includes weight-bearing physical activity (such as walking and running). Osteoporosis is a disease of the ...

  7. Calcium

    Science.gov (United States)

    ... for dinner. Create mini-pizzas by topping whole-wheat English muffins or bagels with pizza sauce and ... Fitness Center Vitamin D Smart Supermarket Shopping Lactose Intolerance Vitamins and Minerals Vitamin Chart Mineral Chart Food ...

  8. Decolorization of azo dyes by Geobacter metallireducens.

    Science.gov (United States)

    Liu, Guangfei; Zhou, Jiti; Chen, Congcong; Wang, Jing; Jin, Ruofei; Lv, Hong

    2013-09-01

    Geobacter metallireducens was found to be capable of decolorizing several azo dyes with different structures to various extents. Pyruvate, ethanol, acetate, propionate, and benzoate could support 66.3 ± 2.6-93.7 ± 2.1 % decolorization of 0.1 mM acid red 27 (AR27) in 40 h. The dependence of the specific decolorization rate on AR27 concentration (25 to 800 μM) followed Michaelis-Menten kinetics (K m = 186.9 ± 1.4 μΜ, V max = 0.65 ± 0.02 μmol mg protein(-1) h(-1)). Enhanced AR27 decolorization was observed with the increase of cell concentrations ranging from 7.5 to 45 mgL(-1). AR27 decolorization by G. metallireducens was retarded by the presence of goethite, which competed electrons with AR27 and was reduced to Fe(II). The addition of low concentrations of humic acid (1-100 mgL(-1)) or 2-hydroxy-1,4-naphthoquinone (0.5-50 μM) could improve the decolorization performance of G. metallireducens. High-performance liquid chromatography analysis suggested reductive pathway to be responsible for decolorization. This was the first study on azo dye decolorization by Geobacter strain and might improve our understanding of natural attenuation and bioremediation of environments polluted by azo dyes.

  9. Testosterone increases urinary calcium excretion and inhibits expression of renal calcium transport proteins.

    NARCIS (Netherlands)

    Hsu, Y.J.; Dimke, H.; Schoeber, J.P.H.; Hsu, S.C.; Lin, S.H.; Chu, P.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2010-01-01

    Although gender differences in the renal handling of calcium have been reported, the overall contribution of androgens to these differences remains uncertain. We determined here whether testosterone affects active renal calcium reabsorption by regulating calcium transport proteins. Male mice had hig

  10. 76 FR 51991 - Determination That PENTETATE CALCIUM TRISODIUM (Trisodium Calcium Diethylenetriaminepentaacetate...

    Science.gov (United States)

    2011-08-19

    ... new drug applications (ANDAs) for PENTETATE CALCIUM TRISODIUM (Ca-DTPA) solution for intravenous or... ANDA that does not refer to a listed drug. PENTETATE CALCIUM TRISODIUM (Ca-DTPA) solution for... HUMAN SERVICES Food and Drug Administration Determination That PENTETATE CALCIUM TRISODIUM...

  11. Effect of lowering dietary calcium intake on fractional whole body calcium retention

    Energy Technology Data Exchange (ETDEWEB)

    Dawson-Hughes, B.; Stern, D.T.; Shipp, C.C.; Rasmussen, H.M.

    1988-07-01

    Although fractional calcium absorption is known to vary inversely with calcium intake, the extent and timing of individual hormonal and calcium absorption responses to altered calcium intake have not been defined. We measured fractional whole body retention of orally ingested /sup 47/Ca, an index of calcium absorption, in nine normal women after they had eaten a 2000-mg calcium diet for 8 weeks and a 300-mg calcium diet for 1, 2, 4, and 8 weeks. After the diet change, serum intact PTH (32.2% increase; P = 0.005), serum 1,25-dihydroxyvitamin D (1,25-(OH)2D; 43.8% increase; P = 0.003), and fractional whole body calcium retention (42.8% increase; P = 0.004) increased within 1 week. Although the PTH and calcium retention responses remained fairly constant throughout the low calcium intake period, serum 1,25-(OH)2D concentrations declined toward baseline after week 1. Thus, the late increase in calcium retention may have resulted from calcium absorption that was independent of 1,25-(OH)2D stimulation.

  12. Protein intake and calcium absorption – Potential role of the calcium sensor receptor

    Science.gov (United States)

    Dietary protein induces calcium excretion but the source of this calcium is unclear. Evidence from short-term studies indicates that protein promotes bone resorption, but many epidemiologic studies do not corroborate this. Evidence is also mixed on weather protein promotes calcium absorption. Stud...

  13. Resonance energy transfer: Dye to metal nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wari, M. N.; Pujar, G. H.; Inamdar, S. R., E-mail: him-lax3@yahoo.com [Laser Spectroscopy Programme, Department of Physics, Karnatak University, Dharwad-580003 (India)

    2015-06-24

    In the present study, surface energy transfer (SET) from Coumarin 540A (C540 A) to Gold nanoparticle (Au) is demonstrated. The observed results show pronounced effect on the photoluminescence intensity and shortening of the lifetime of Coumarin 540A upon interaction with the spherical gold nanoparticle, also there are measured effects on radiative rate of the dye. Experimental results are analyzed with fluorescence resonance energy transfer (FRET) and SET theories. The results obtained from distance-dependent quenching provide experimental evidence that the efficiency curve slope and distance of quenching is best modeled by surface energy transfer process.

  14. Hair dye poisoning: An unusual encounter

    Directory of Open Access Journals (Sweden)

    Sunil Kumar Garg

    2014-01-01

    Full Text Available A 19-year-old female patient presented with alleged history of hair dye "Super Vasmol 33" intake. She presented with cervicofacial edema with upper airway obstruction. Although patient was being managed for airway obstruction, she developed cardiac arrest. Cardiac resuscitation could not be started at that point of time because managing airway was the priority in a patient who in hypoxic cardiac arrest. As soon as the airway was secured by emergency tracheostomy, cardiac resuscitation was initiated and the patient was successfully revived.

  15. Calcium signaling in pluripotent stem cells.

    Science.gov (United States)

    Apáti, Ágota; Pászty, Katalin; Erdei, Zsuzsa; Szebényi, Kornélia; Homolya, László; Sarkadi, Balázs

    2012-04-28

    Pluripotent stem cells represent a new source of biological material allowing the exploration of signaling phenomena during normal cell development and differentiation. Still, the calcium signaling pathways and intracellular calcium responses to various ligands or stress conditions have not been sufficiently explored as yet in embryonic or induced pluripotent stem cells and in their differentiated offspring. This is partly due to the special culturing conditions of these cell types, the rapid morphological and functional changes in heterogeneous cell populations during early differentiation, and methodological problems in cellular calcium measurements. In this paper, we review the currently available data in the literature on calcium signaling in pluripotent stem cells and discuss the potential shortcomings of these studies. Various assay methods are surveyed for obtaining reliable data both in undifferentiated embryonic stem cells and in specific, stem cell-derived human tissues. In this paper, we present the modulation of calcium signaling in human embryonic stem cells (hESC) and in their derivates; mesenchymal stem cell like (MSCl) cells and cardiac tissues using the fluorescent calcium indicator Fluo-4 and confocal microscopy. LPA, trypsin and angiotensin II were effective in inducing calcium signals both in HUES9 and MSCl cells. Histamine and thrombin induced calcium signal exclusively in the MSCl cells, while ATP was effective only in HUES9 cells. There was no calcium signal evoked by GABA, even at relatively high concentrations. In stem cell-derived cardiomyocytes a rapid increase in the beating rate and an increase of the calcium signal peaks could be observed after the addition of adrenaline, while verapamil led to a strong decrease in cellular calcium and stopped spontaneous contractions in a relaxed state.

  16. Biological waste-water treatment of azo dyes

    Energy Technology Data Exchange (ETDEWEB)

    Shaul, G.M.; Dempsey, C.R.; Dostal, K.A.

    1988-05-01

    The U.S. Environmental Protection Agency's (EPA) Office of Toxic Substances evaluates existing chemicals under Section 4 of the Toxic Substances Control Act (TSCA) and Premanufacture Notification (PMN) submissions under Section 5 of TSCA. Azo dyes constitute a significant portion of these PMN submissions and specific azo dyes have recently been added to the priority list for considerations in the development of test rules under Section 4. Azo dyes are of concern because some of the dyes, dye precurors, and/or their degradation products such as aromatic amines (which are also dye precurors) have been shown to be, or are suspected to be, carcinogenic. The fate of azo dyes in biological waste-water treatment systems was studied to aid in the review of PMN submissions and to assist in the possible development of test rules. Results from extensive pilot-scale activated-sludge process testing for 18 azo dyes are presented. Results from fate studies of C.I. Disperse Blue 79 in aerobic and anaerobic waste-water treatment will also be presented.

  17. 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.

  18. Sorption and desorption of dyes by sulfonated coal

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, A.K. (Motilal Nehru Regional Coll. of Engineering, Allahabad (India)); Venkobachar, C. (Indian Inst. of Tech., Kanpur (India))

    Wastewaters from dye-manufacturing factories and textile, paper, and pulp industries are highly colored. Their discharge into river waters make the water inhibitory to aquatic life, aside from causing, visible pollution. Dyes have a tendency to sequester metals, thus causing microtoxicity to fish and other aquatic organisms. A wide variety of low-cost materials such as flyash, clay minerals, coal, tire chippings, coconut shell powder and biosorbents are being tried as viable substitutes for activated carbon to remove different pollutants such as pesticides, heavy metals, and dyes. The removal of dyes depends upon their physical and chemical characteristics, as well as the properties of the selected sorbents. To understand the nature of the chemical bonding between dyes and sorbents during the sorption process, it is essential to conduct desorption studies. The reversibility of adsorption of dyes can also be determined by a simple mathematical equation. These studies provide information on whether or not the sorbent material can be regenerated after exhaustion. The present study focuses on sorption-desorption of dyes by sulfonated coal, whose dye sorption potential was established by Mittal and Venkobachar (1990).

  19. Types of Hair Dye and Their Mechanisms of Action

    Directory of Open Access Journals (Sweden)

    Simone Aparecida da França

    2015-04-01

    Full Text Available Hair color change by dye application is a common procedure among women. Hair dyes are classified, according to color resistance, into temporary, semipermanent, demipermanent and permanent. The first two are based on molecules which are already colored. Temporary dyes act through dye deposition on cuticles, but semipermanent may penetrate a little into the cortex and so the color resists up to six washes. Demipermanent and permanent dyes are based on color precursors, called oxidation dyes, and the final shade is developed by their interactions with an oxidizing agent, but they differ from the alkalizing agent used. In oxidation systems, there is an intense diffusion of the molecules into the cortex, what promotes a longer color resistance. Dyes and color precursors present differences related to chromophore groups, hair fiber affinity, water solubility, and photo stability. The aim of this review is to discuss the differences among hair dye products available in the market and their action mechanisms, molecular structures, application methods, and some aspects of formulations.

  20. An Interdisciplinary Experiment: Azo-Dye Metabolism by "Staphylococcus Aureus"

    Science.gov (United States)

    Brocklesby, Kayleigh; Smith, Robert; Sharp, Duncan

    2012-01-01

    An interdisciplinary and engaging practical is detailed which offers great versatility in the study of a qualitative and quantitative metabolism of azo-dyes by "Staphylococcus aureus". This practical has broad scope for adaptation in the number and depth of variables to allow a focused practical experiment or small research project. Azo-dyes are…