Modeling Residual NAPL in Water-Wet Porous Media

Directory of Open Access Journals (Sweden)

R.J. Lenhard

2002-06-01

Full Text Available A model is outlined that predicts NAPL which is held in pore wedges and as films or lenses on solid and water surfaces and contributes negligibly to NAPL advection. This is conceptually referred to as residual NAPL. Since residual NAPL is immobile, it remains in the vadose zone after all free NAPL has drained. Residual NAPL is very important because it is a long-term source for groundwater contamination. Recent laboratory experiments have demonstrated that current models for predicting subsurface NAPL behavior are inadequate because they do not correctly predict residual NAPL. The main reason for the failure is a deficiency in the current constitutive theories for multiphase flow that are used in numerical simulators. Multiphase constitutive theory governs the relations among relative permeability, saturation, and pressure for fluid systems (i.e., air, NAPL, water. In this paper, we outline a model describing relations between fluid saturations and pressures that can be combined with existing multiphase constitutive theory to predict residual NAPL. We test the revised constitutive theory by applying it to a scenario involving NAPL imbibition and drainage, as well as water imbibition and drainage. The results suggest that the revised constitutive theory is able to predict the distribution of residual NAPL in the vadose zone as a function of saturation-path history. The revised model describing relations between fluid saturation and pressures will help toward developing or improving numerical multiphase flow simulators.

A Study of Residual Amplitude Modulation Suppression in Injection Locked Quantum Cascade Lasers Based on a Simplified Rate Equation Model

International Nuclear Information System (INIS)

Webb, J F; Yong, K S C; Haldar, M K

2015-01-01

Using results that come out of a simplified rate equation model, the suppression of residual amplitude modulation in injection locked quantum cascade lasers with the master laser modulated by its drive current is investigated. Quasi-static and dynamic expressions for intensity modulation are used. The suppression peaks at a specific value of the injection ratio for a given detuning and linewidth enhancement factor. The intensity modulation suppression remains constant over a range of frequencies. The effects of injection ratio, detuning, coupling efficiency and linewidth enhancement factor are considered. (paper)

Characterisation of some South African water treatment residues ...

African Journals Online (AJOL)

2005-07-03

Jul 3, 2005 ... Land application of water treatment residue (WTR) the by-product from the production of potable water, is becoming the preferred ... were analysed for some physical (particle size distribution, particle density and plant available water) and chemical attributes ...... for Industrial Wastes – Theory and Practice.

Guidance Preconditioning by an Impulse Sequence for Robust Residual Vibration Suppression

Directory of Open Access Journals (Sweden)

I. Antoniadis

1999-01-01

Full Text Available In order to suppress residual vibrations, a general method is presented for preconditioning any guidance function prior to its application to a dynamic system, by convolving it with a sequence of impulses. The approach includes first the development of the necessary design specifications for the impulse sequence, so that the robustness properties cover the widest possible variation of the system natural frequencies. Three solution methods are proposed then, with special emphasis in the achievement of the minimum possible duration time of the impulse sequence. Numerical experiments verify the effectiveness of the robustness, not only with respect to variations of the natural frequency, but also with respect to variations of a range of other linear and non-linear variables.

Earth's field NMR detection of oil under arctic ice-water suppression

Science.gov (United States)

Conradi, Mark S.; Altobelli, Stephen A.; Sowko, Nicholas J.; Conradi, Susan H.; Fukushima, Eiichi

2018-03-01

Earth's field NMR has been developed to detect oil trapped under or in Arctic sea-ice. A large challenge, addressed here, is the suppression of the water signal that dominates the oil signal. Selective suppression of water is based on relaxation time T1 because of the negligible chemical shifts in the weak earth's magnetic field, making all proton signals overlap spectroscopically. The first approach is inversion-null recovery, modified for use with pre-polarization. The requirements for efficient inversion over a wide range of B1 and subsequent adiabatic reorientation of the magnetization to align with the static field are stressed. The second method acquires FIDs at two durations of pre-polarization and cancels the water component of the signal after the data are acquired. While less elegant, this technique imposes no stringent requirements. Similar water suppression is found in simulations for the two methods. Oil detection in the presence of water is demonstrated experimentally with both techniques.

Nuclear reactor with makeup water assist from residual heat removal system

Science.gov (United States)

Corletti, Michael M.; Schulz, Terry L.

1993-01-01

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path.

Nuclear reactor with makeup water assist from residual heat removal system

International Nuclear Information System (INIS)

Corletti, M.M.; Schulz, T.L.

1993-01-01

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path. 2 figures

Nuclear reactor with makeup water assist from residual heat removal system

Science.gov (United States)

Corletti, M.M.; Schulz, T.L.

1993-12-07

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path. 2 figures.

Non-water-suppressed 1 H FID-MRSI at 3T and 9.4T.

Science.gov (United States)

Chang, Paul; Nassirpour, Sahar; Avdievitch, Nikolai; Henning, Anke

2018-08-01

This study investigates metabolite concentrations using metabolite-cycled 1 H free induction decay (FID) magnetic resonance spectroscopic imaging (MRSI) at ultra-high fields. A non-lipid-suppressed and slice-selective ultra-short echo time (TE) 1 H FID MRSI sequence was combined with a low-specific absorption rate (SAR) asymmetric inversion adiabatic pulse to enable non-water-suppressed metabolite mapping using metabolite-cycling at 9.4T. The results were compared to a water-suppressed FID MRSI sequence, and the same study was performed at 3T for comparison. The scan times for performing single-slice metabolite mapping with a nominal voxel size of 0.4 mL were 14 and 17.5 min on 3T and 9.4T, respectively. The low-SAR asymmetric inversion adiabatic pulse enabled reliable non-water-suppressed metabolite mapping using metabolite cycling at both 3T and 9.4T. The spectra and maps showed good agreement with the water-suppressed FID MRSI ones at both field strengths. A quantitative analysis of metabolite ratios with respect to N-acetyl aspartate (NAA) was performed. The difference in Cre/NAA was statistically significant, ∼0.1 higher for the non-water-suppressed case than for water suppression (from 0.73 to 0.64 at 3T and from 0.69 to 0.59 at 9.4T). The difference is likely because of chemical exchange effects of the water suppression pulses. Small differences in mI/NAA were also statistically significant, however, are they are less reliable because the metabolite peaks are close to the water peak that may be affected by the water suppression pulses or metabolite-cycling inversion pulse. We showed the first implementation of non-water-suppressed metabolite-cycled 1 H FID MRSI at ultra-high fields. An increase in Cre/NAA was seen for the metabolite-cycled case. The same methodology was further applied at 3T and similar results were observed. Magn Reson Med 80:442-451, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society

Pesticide residue analysis of soil, water, and grain of IPM basmati rice.

Science.gov (United States)

Arora, Sumitra; Mukherji, Irani; Kumar, Aman; Tanwar, R K

2014-12-01

The main aim of the present investigations was to compare the pesticide load in integrated pest management (IPM) with non-IPM crops of rice fields. The harvest samples of Basmati rice grain, soil, and irrigation water, from IPM and non-IPM field trials, at villages in northern India, were analyzed using multi-pesticide residue method. The field experiments were conducted for three consecutive years (2008-2011) for the successful validation of the modules, synthesized for Basmati rice, at these locations. Residues of tricyclazole, propiconazole, hexconazole, lambda cyhalothrin, pretilachlor chlorpyrifos, DDVP, carbendazim, and imidacloprid were analyzed from two locations, Dudhli village of Dehradun, Uttrakhand and Saboli and Aterna village of Sonepat, Haryana. The pesticide residues were observed below detectable limit (BDL) (water samples (2008-09). Residues of tricyclazole and carbendazim, analyzed from same locations, revealed pesticide residues as BDL (water samples (2009-2010). The residues of tricyclazole, propioconazole, chlorpyrifos, hexaconazole, pretilachlor, and λ-cyhalothrin were also found as BDL (water samples (<0.001-0.05 μg/L) (2010-2011).

Selenium Adsorption To Aluminum-Based Water Treatment Residuals

Science.gov (United States)

Aluminum-based water treatment residuals (WTR) can adsorb water-and soil-borne P, As(V), As(III), and perchlorate, and may be able to adsorb excess environmental selenium. WTR, clay minerals, and amorphous aluminum hydroxide were shaken for 24 hours in selenate or selenite solut...

Model-based leakage localization in drinking water distribution networks using structured residuals

OpenAIRE

Puig Cayuela, Vicenç; Rosich, Albert

2013-01-01

In this paper, a new model based approach to leakage localization in drinking water networks is proposed based on generating a set of structured residuals. The residual evaluation is based on a numerical method based on an enhanced Newton-Raphson algorithm. The proposed method is suitable for water network systems because the non-linearities of the model make impossible to derive analytical residuals. Furthermore, the computed residuals are designed so that leaks are decoupled, which impro...

Water relations, gas exchange and growth of dominant and suppressed shoots of Arbutus unedo L.

Science.gov (United States)

Castell, C; Terradas, J

1995-06-01

Basal shoots produced by Arbutus unedo L. after cutting at ground level vary in size and growth rate, and are classified accordingly as dominant or suppressed. The suppressed shoots eventually cease growth and die. In this study, we investigated the role of light and water in the competition among shoots of A. unedo. Dominant and suppressed shoots of A. unedo showed similar leaf water potentials and tissue water relations over the year, suggesting that water status is not responsible for the lack of flushing in suppressed shoots. Although suppressed shoots did not flush under low light, they showed many characteristics of shade-tolerant plants. Leaves of suppressed shoots had lower leaf conductance and light-saturated photosynthetic rate, and higher specific leaf area than leaves of dominant shoots. We conclude that light was the main resource determining competition among shoots and the death of suppressed shoots.

Impacts of alum residues from Morton Jaffray Water Works on water quality and fish, Harare, Zimbabwe

Science.gov (United States)

Muisa, Norah; Hoko, Zvikomborero; Chifamba, Portia

Metal pollution of freshwater due to human activities is a major problem confronting most urban centres in developing countries. This study determined the extent to which aluminium in the residues from Morton Jaffray Water Works in Harare were affecting the water quality of Manyame River and Lake Manyame. The study also measured aluminium bioaccumulation in Nile Tilapia ( Oreochromis niloticus) which is of importance to the commercial fisheries industry in Zimbabwe. Depth integrated water, and sediment grab samples and adult fish were collected per site in January and March, 2010. A total of six sites were selected on the Manyame River and in Lake Manyame. The levels of Total Aluminium (Al) were determined in sediments, water and fish tissues (liver, kidney, gill and muscle). Total solids, total dissolved solids, conductivity, pH, dissolved oxygen and temperature were also determined in water and residues. The texture of the sediments was also assessed. Aluminium concentration in water ranged from 2.19 mg/L to 68.93 mg/L during both sampling campaigns surpassing permissible maximum concentration limits of 0.087 to 0.75 mg/L suggested by the Environmental Protection Agency and African Union. The site upstream of the discharge point of the residues always had the lowest levels though it was higher than acceptable levels indicated above, thus suggesting the existence of other sources of aluminium in the catchment besides Morton Jaffray Water Works. However, there was a 10-fold and 100-fold increase in levels of aluminium in water and sediments, respectively, at the site 100 m downstream of the discharge point on the Manyame River. Mean aluminium concentrations in water and sediments at this site averaged 68.93 ± 61.74 mg/L and 38.18 ± 21.54 mg/L in water and 103.79 ± 55.96 mg/L and 131.84 ± 16.48 mg/L in sediments in sampling campaigns 1 and 2, respectively. These levels were significantly higher than levels obtained from all the other sites during both sampling

Suppress flashover of GRP fire with water mist inside ISO 9705 Room

Directory of Open Access Journals (Sweden)

Qiang Xu

2011-01-01

Full Text Available Water mist suppression tests for glass-reinforced polyester (GRP panels were conducted in ISO 9705 room. GRP panels covered part of the room and a wood crib fire was used as fire source to ignite GRP fire. A four-nozzle water mist suppression equipment was used inside test room on the time of flashover. Heat release rate of the combustion inside the room, room temperature, surface temperature of GRP panels, total heat flux to wall, ceiling and floor in specific positions were measured. Gas concentration of O2, CO, and CO2 was also measured in the corner of the room at two different levels. A thermal image video was used to record the suppression procedure inside room. Test results show that the water mist system is efficient in suppressing the flashover of GRP fire and cooling the room within short time.

Nuclear reactor with makeup water assist from residual heat removal system

International Nuclear Information System (INIS)

Schulz, T.L.; Corletti, M.M.

1994-01-01

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit by pumping water from an in-containment refueling water storage tank during staged depressurization of the coolant circuit, the final stage including passive emergency cooling by gravity feed from the refueling water storage tank to the coolant circuit and to flood the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and avoids the final stage of depressurization with its flooding of the containment when such action is not necessary, but does not prevent the final stage when it is necessary. A high pressure makeup water storage tank coupled to the reactor coolant circuit holds makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal system can also be coupled in a loop with the refueling water supply tanks for cooling the tank. (Author)

Selenium-Water Treatment Residual Adsorption And Characterization

Science.gov (United States)

Aluminum-based water treatment residuals (WTR) have the ability to adsorb tremendous quantities of soil-borne P, and have been shown to adsorb other anions, such as As (V), As (III), and ClO4-. Environmental issues associated with Se in the Western US led us to study W...

The effect of sludge water treatment plant residuals on the properties of compressed brick

Science.gov (United States)

Shamsudin, Shamrul-Mar; Shahidan, S.; Azmi, M. A. M.; Ghaffar, S. A.; Ghani, M. B. Abdul; Saiful Bahari, N. A. A.; Zuki, S. S. M.

2017-11-01

The focus of this study is on the production of compressed bricks which contains sludge water treatment plant (SWTP) residuals obtained from SAJ. The main objective of this study is to utilise and incorporate discarded material (SWTP) in the form of residual solution to produce compressed bricks. This serves as one of the recycling efforts to conserve the environment. This study determined the optimum mix based on a mix ratio of 1:2:4 (cement: sand: soil) in the production of compressed bricks where 5 different mixes were investigated i. e. 0%, 5%, 10%, 20%, and 30% of water treatment plant residue solution. The production of the compressed bricks is in accordance with the Malaysian Standard MS 7.6: 1972 and British Standard BS 3921: 1985 - Compressive Strength & Water Absorption. After being moulded and air dried, the cured bricks were subjected to compression tests and water absorption tests. Based on the tests conducted, it was found that 20% of water treatment plant residue solution which is equivalent to 50% of soil content replacement with a mix composition of [10: cement] [20: sand] [20: soil] [20: water treatment plant residue solution] is the optimum mix. It was also observed that the bricks containing SWTP residuals were lighter in weight compared to the control specimens

Residual stress improvement in multi-layer welded plates using water-shower cooling during welding process

International Nuclear Information System (INIS)

Yanagida, Nobuyoshi; Koide, Hiroo

2006-01-01

To reduce tensile residual stress in a welded region, we developed a new welding method that applies a water-shower behind the welding torch. When this method is applied to welding of austenitic stainless steel plates, cooling conditions mainly determine how much the residual stress can be reduced. To determine the conditions, we first used FEM to evaluate the effects of interpass temperature on the residual stress. And we found effective conditions for reducing tensile residual stress. To verify the validity of the conditions, specimens welded with or without water shower cooling were manufactured. Residual stresses of the specimens were experimentally measured. It was found that tensile residual stresses were generated on the surface of the welds and those were reduced in the case that the water-shower was applied. These measurement results agree well with the FEM analyses. It can therefore be concluded that the water-shower cooling during welding is appropriate for reducing tensile residual stress in austenitic stainless steel welding. (author)

Assessment of heavy metal residues in water, fish tissue and human ...

African Journals Online (AJOL)

MICHAEL HORSFALL

ABSTRACT: Residual levels of lead, chromium, cadmium and zinc in water and fish tissue from. Ubeji River ... Key Words : Heavy metal residues , Fish tissue, Human blood, Ubeji River. ... is of critical concern because of their toxicity and.

Temperature-dependent dynamical transitions of different classes of amino acid residue in a globular protein.

Science.gov (United States)

Miao, Yinglong; Yi, Zheng; Glass, Dennis C; Hong, Liang; Tyagi, Madhusudan; Baudry, Jerome; Jain, Nitin; Smith, Jeremy C

2012-12-05

The temperature dependences of the nanosecond dynamics of different chemical classes of amino acid residue have been analyzed by combining elastic incoherent neutron scattering experiments with molecular dynamics simulations on cytochrome P450cam. At T = 100-160 K, anharmonic motion in hydrophobic and aromatic residues is activated, whereas hydrophilic residue motions are suppressed because of hydrogen-bonding interactions. In contrast, at T = 180-220 K, water-activated jumps of hydrophilic side chains, which are strongly coupled to the relaxation rates of the hydrogen bonds they form with hydration water, become apparent. Thus, with increasing temperature, first the hydrophobic core awakens, followed by the hydrophilic surface.

Interactive effects of rice residue and water stress on growth and metabolism of wheat seedlings

Directory of Open Access Journals (Sweden)

Nimisha Amist

2014-08-01

Full Text Available In the present study effects of rice residue with and without water stress were studied on Triticum aestivum L. cv. Shatabadi. The mixture of residue and garden soil in 1:1 ratio was considered as 50% (R1 and only decomposed residue as 100% (R2. Garden soil was taken as control. Twenty five seeds were sown in each experimental trays filled with soil mixture according to the treatments. Trays were arranged in two groups. After 15 days one set was subjected to water stress (WS by withholding water supply for 3 days. Morphological and biochemical parameters of 18 days old seedlings were recorded. Seedling height decreased in all treatments. A gradual decrease in relative water content, pigment and protein contents of wheat seedlings were observed. Sugar and proline contents increased in treatments. An increase in malondialdehyde (MDA content and antioxidative enzyme activities was recorded. Elevation in catalase activity was observed in all treatments except in plants with water deficit. Ascorbate peroxidase (APX and guaiacol peroxidase (GPX activities increased when residue mixed with soil but decreased in seedlings under the combined influence of the residue and water stress. Higher amount of MDA and lower activities of APX and GPX reflected the oxidative damage in seedlings under combined treatments. Rice residue inhibited growth of wheat seedlings. Water stress intensified the effects of residue.

Evaporation suppression from water reservoirs using floating covers: Lab scale observations and model predictions

Science.gov (United States)

Or, D.; Lehmann, P.; Aminzadeh, M.; Sommer, M.; Wey, H.; Wunderli, H.; Breitenstein, D.

2016-12-01

The competition over dwindling fresh water resources is expected to intensify with projected increase in human population in arid regions, expansion of irrigated land and changes in climate and drought patterns. The volume of water stored in reservoirs would also increase to mitigate seasonal shortages due to rainfall variability and to meet irrigation water needs. By some estimates up to half of the stored water is lost to evaporation thereby exacerbating the water scarcity problem. Recently, there is an upsurge in the use of self-assembling floating covers to suppress evaporation, yet the design, and implementation remain largely empirical. Studies have shown that evaporation suppression is highly nonlinear, as also known from a century of research on gas exchange from plant leaves (that often evaporate as free water surfaces through stomata that are only 1% of leaf area). We report a systematic evaluation of different cover types and external drivers (radiation, wind, wind+radiation) on evaporation suppression and energy balance of a 1.4 m2 basin placed in a wind-tunnel. Surprisingly, evaporation suppression by black and white floating covers (balls and plates) were similar despite significantly different energy balance regimes over the cover surfaces. Moreover, the evaporation suppression efficiency was a simple function of the uncovered area (square root of the uncovered fraction) with linear relations with the covered area in some cases. The thermally decoupled floating covers offer an efficient solution to the evaporation suppression with limited influence of the surface energy balance (water temperature for black and white covers was similar and remained nearly constant). The results will be linked with a predictive evaporation-energy balance model and issues of spatial scales and long exposure times will be studied.

Effect of water content and organic carbon on remote sensing of crop residue cover

Science.gov (United States)

Serbin, G.; Hunt, E. R., Jr.; Daughtry, C. S. T.; McCarty, G. W.; Brown, D. J.; Doraiswamy, P. C.

2009-04-01

Crop residue cover is an important indicator of tillage method. Remote sensing of crop residue cover is an attractive and efficient method when compared with traditional ground-based methods, e.g., the line-point transect or windshield survey. A number of spectral indices have been devised for residue cover estimation. Of these, the most effective are those in the shortwave infrared portion of the spectrum, situated between 1950 and 2500 nm. These indices include the hyperspectral Cellulose Absorption Index (CAI), and advanced multispectral indices, i.e., the Lignin-Cellulose Absorption (LCA) index and the Shortwave Infrared Normalized Difference Residue Index (SINDRI), which were devised for the NASA Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor. Spectra of numerous soils from U.S. Corn Belt (Indiana and Iowa) were acquired under wetness conditions varying from saturation to oven-dry conditions. The behavior of soil reflectance with water content was also dependent on the soil organic carbon content (SOC) of the soils, and the location of the spectral bands relative to significant water absorptions. High-SOC soils showed the least change in spectral index values with increase in soil water content. Low-SOC soils, on the other hand, showed measurable difference. For CAI, low-SOC soils show an initial decrease in index value followed by an increase, due to the way that water content affects CAI spectral bands. Crop residue CAI values decrease with water content. For LCA, water content increases decrease crop residue index values and increase them for soils, resulting in decreased contrast. SINDRI is also affected by SOC and water content. As such, spatial information on the distribution of surface soil water content and SOC, when used in a geographic information system (GIS), will improve the accuracy of remotely-sensed crop residue cover estimates.

Abdominal adipose tissue quantification on water-suppressed and non-water-suppressed MRI at 3T using semi-automated FCM clustering algorithm

Science.gov (United States)

Valaparla, Sunil K.; Peng, Qi; Gao, Feng; Clarke, Geoffrey D.

2014-03-01

Accurate measurements of human body fat distribution are desirable because excessive body fat is associated with impaired insulin sensitivity, type 2 diabetes mellitus (T2DM) and cardiovascular disease. In this study, we hypothesized that the performance of water suppressed (WS) MRI is superior to non-water suppressed (NWS) MRI for volumetric assessment of abdominal subcutaneous (SAT), intramuscular (IMAT), visceral (VAT), and total (TAT) adipose tissues. We acquired T1-weighted images on a 3T MRI system (TIM Trio, Siemens), which was analyzed using semi-automated segmentation software that employs a fuzzy c-means (FCM) clustering algorithm. Sixteen contiguous axial slices, centered at the L4-L5 level of the abdomen, were acquired in eight T2DM subjects with water suppression (WS) and without (NWS). Histograms from WS images show improved separation of non-fatty tissue pixels from fatty tissue pixels, compared to NWS images. Paired t-tests of WS versus NWS showed a statistically significant lower volume of lipid in the WS images for VAT (145.3 cc less, p=0.006) and IMAT (305 cc less, p1), but not SAT (14.1 cc more, NS). WS measurements of TAT also resulted in lower fat volumes (436.1 cc less, p=0.002). There is strong correlation between WS and NWS quantification methods for SAT measurements (r=0.999), but poorer correlation for VAT studies (r=0.845). These results suggest that NWS pulse sequences may overestimate adipose tissue volumes and that WS pulse sequences are more desirable due to the higher contrast generated between fatty and non-fatty tissues.

USAGE OF ALGAE SPECIES CHAETOMORPHA GRACILIS AND CH. AEREA FOR DEPURATION PROCESS OF THE RESIDUAL WATERS

Directory of Open Access Journals (Sweden)

SALARU VICTOR

2008-11-01

Full Text Available Rapid increase of the population on the globe scale imposes maximum exploration of the natural resources and first of all of the aquatic resources. As a result are obtained an enormous quantity of residual waters which pollute the waters from rivers, lakes, freatic and underground waters. Elaboration of the depuration methods for residual waters the quantity of which grows continuously, is one of the most up to dated issue of the world. The physical-chemical depuration methods of the residual waters are very expensive and lack the efficiency we would like to have. The most efficient method proved to be the biological method using some species of algae and superior aquatic plants. In our experiences we have involved filamentous green algae Chaetomorpha gracilis and Ch. aerea for depuration of the sewerage water from town Cimishlia. The concentration of the mineral nitrogen compounds in the residual water is around 92,5 mg/l, and of the phosphates 10,1 mg/l. There were used the following concentration of the sewerage water: 10%, 25% and 50%. The most intense development of algae Chaetomorpha aerea was observed in the variant with 10% of residual water, in which the total concentration of the nitrogen was 10,24 mg/l, and of the phosphates 1,05 mg/l. For this variant the depuration water level was about 56,9%. For the case with Chaetomorpha gracilis, the depuration level for the same concentration of the residual water constituted 55,9 %. Increase of the concentration of the polluted water inhibits development of the algae reducing to the minimum their capacity to assimilate the nitrogen and the phosphor. In the solutions with 50 % of residual waters, the algae didn't die, but at the same time they didn't develop. From this results that both algae may be used in the phytoamelioration of the residual waters being diluted at 10% with purified water.

Pesticide residues and microbial contamination of water resources in the MUDA rice agroecosystem

International Nuclear Information System (INIS)

Cheah Uan Boh; Lum Keng Yeang

2002-01-01

Studies on the water resources of the Muda rice growing areas revealed evidence of pesticide residues in the agroecosystem. While the cyclodiene endosulfan was found as a ubiquitous contaminant, the occurrence of other organochlorine insecticides was sporadic. The presence of 2,4-D, paraquat and molinate residues was also evident but the occurrence of these herbicides was seasonal. Residue levels of molinate were generally higher than those from the other herbicides. The problem of thiobencarb and carbofuran residues was not encountered. Analyses for microbial contamination revealed that the water resources were unfit for drinking; coliform counts were higher during certain periods of the year than others. (Author)

Cold vacuum drying residual free water test description

International Nuclear Information System (INIS)

Pajunen, A.L.

1997-01-01

Residual free water expected to remain in a Multi-Canister Overpack (MCO) after processing in the Cold Vacuum Drying (CVD) Facility is investigated based on three alternative models of fuel crevices. Tests and operating conditions for the CVD process are defined based on the analysis of these models. The models consider water pockets constrained by cladding defects, water constrained in a pore or crack by flow through a porous bed, and water constrained in pores by diffusion. An analysis of comparative reaction rate constraints is also presented indicating that a pressure rise test can be used to show MCO's will be thermally stable at operating temperatures up to 75 C

Removal of six pesticide residues in cowpea with alkaline electrolysed water.

Science.gov (United States)

Han, Yongtao; Song, Le; An, Quanshun; Pan, Canping

2017-06-01

Reduction of six pesticide residues (isoprocarb, chlorpyrifos, bifenthrin, beta-cypermethrin, difenoconazole and azoxystrobin) in cowpea by alkaline electrolysed water (AlEW) solutions with different pH was investigated. The commonly used washing treatments in household processing were used for comparison. The residue magnitudes were determined by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). Results showed that the removal effect of AlEW solution on the six pesticides was superior to tap water, 5% sodium chloride, 5% sodium carbonate and 5% acetic acid solution. AlEW with pH 12.2 had more potential to eliminate the six pesticides in cowpeas. Moreover, the reduction of pesticide residues gradually increased with the increase of washing time. This study demonstrated that AlEW solution with pH of 12.2 could be used to reduce pesticide residues on fresh cowpea samples. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

The numerical comparison of fire combustion model and water-mist suppression with experiments by FDS code

International Nuclear Information System (INIS)

Li Hsuennien; Ferng Yuhming; Shih Chunkuan; Hsu Wensheng

2007-01-01

FDS [1] code numerically solves a form of the Navier-Stokes equations appropriate for low-speed, thermally driven flow with an emphasis on smoke and heat transport from fires. FDS uses a mixture fraction combustion model. The mixture fraction is a conserved scalar quantity that is defined as the fraction of fuel gas at a given point in the flow field. The model assumes that combustion is mixing-controlled, and that the reaction of fuel and oxygen is infinitely fast. In FDS, Lagrangian particles are used to simulate smoke movement and sprinkling water-mist discharge. In order to evaluate the combustion model and water-mist suppression function of the code, FDS analyses are conducted to simulate two enclosure fire cases available in the literature. Comparisons with other combustion models are also made. For fires suppression by water-mist in FDS, parametric studies are performed to compare various water-mist injection characteristics for maximum suppression. Numerical results indicate that the flame suppression is closely related to characteristics of the water mist, such as droplet diameter, mist injection velocity, injection density. Our present investigations show that the combustion model and water-mist suppression in FDS can provide simulation results that are comparable with the experiments. (author)

Physical model of lean suppression pressure oscillation phenomena: steam condensation in the light water reactor pressure suppression system (PSS)

International Nuclear Information System (INIS)

McCauley, E.W.; Holman, G.S.; Aust, E.; Schwan, H.; Vollbrandt, J.

1980-01-01

Using the results of large scale multivent tests conducted by GKSS, a physical model of chugging is developed. The unique combination of accurate digital data and cinematic data has provided the derivation of a detailed, quantified correlation between the dynamic physical variables and the associated two-phase thermo-hydraulic phenomena occurring during lean suppression (chugging) phases of the loss-of-coolant accident in a boiling water reactor pressure suppression system

Bacillus cereus as indicator in the sterilization of residual water with high energy electrons

International Nuclear Information System (INIS)

Mejia Z, E.

2000-01-01

One of the main causes of water pollution is the presence of microorganisms that provoke infections, moreover of chemical substances. The processes of residual water treatment finally require of the disinfection for its use or final disposition. The radiation technology for the residual water treatment by mean of electron beams is an innovator process because as well as decomposing the chemical substance or to degrade them, also it provokes a disinfection by which this is proposed as alternative for disinfection of residual water, with the purpose in reusing the water treated in the agriculture, recreation and industry among others secondary activities, solving environmental or health problems. The objective of this work is to evaluate the use of Bacillus cereus as biological indicator in the disinfection by radiation, using High Energy Electrons. To fulfil with this objective, the work was developed in three stages, the first one consisted in the acquisition, propagation and conservation of the Bacillus cereus stumps, considering Escherichia coli and Salmonella typhimurium as pathogenic germs present in residual water. Moreover, the inocule standardization and the conditions of the Electron accelerator Type Pelletron. In the second stage it was performed the irradiation of aqueous samples of the microorganisms simulating biological pollution and the application to problem samples of a treatment plant sited in the Lerma River zone of mixed residual water. And in the third stage was performed a regression analysis to the reported survival for each kind of microorganisms. The results obtained show that with the use of Electron beams was reduced 6 logarithmic units de E. coli at 129 Gy, for S. typhimurium it was reduced 8 logarithmic units at 383 Gy and the B. cereus at 511 Gy was reduced 6.8 logarithmic units. Of the problem samples irradiated at 500 Gy, the concentration of the total account diminished from 8.70 x 10 7 UFC/ml to 550 UFC/ml, the presence of B. Cereus

Sloshing of water in annular pressure-suppression pool of boiling water reactors under earthquake ground motions

International Nuclear Information System (INIS)

Aslam, M.; Godden, W.G.; Scalise, D.T.

1979-10-01

This report presents an analytical investigation of the sloshing response of water in annular-circular as well as simple-circular tanks under horizontal earthquake ground motions, and the results are verified with tests. This study was motivated because of the use of annular tanks for pressure-suppression pools in Boiling Water Reactors. Such a pressure-suppression pool would typically have 80 ft and 120 ft inside and outside diameters and a water depth of 20 ft. The analysis was based upon potential flow theory and a computer program was written to obtain time-history plots of sloshing displacements of water and the dynamic pressures. Tests were carried out on 1/80th and 1/15th scale models under sinusoidal as well as simulated earthquake ground motions. Tests and analytical results regarding the natural frequencies, surface water displacements, and dynamic pressures were compared and a good agreement was found for relatively small displacements. The computer program gave satisfactory results as long as the maximum water surface displacements were less than 30 in., which is roughly the value obtained under full intensity of El Centro earthquake

Water leaching of titanium from ore flotation residue.

Science.gov (United States)

Jaworska, Malgorzata M; Guibal, Eric

2003-01-01

Copper ore tailings were tested for the stability of titanium submitted to water leaching in three different reactor systems (agitated vessel, bioreactor and percolated fixed-bed column). For each of these systems, titanium extraction did not exceed 1% of the available metal. Biomass removed from ore residue adsorbed a small part of the titanium with sorption capacities below 20-30 mg g(-1), but most of this biomass was sequestered in the ore residue. Oxygen and carbon dioxide concentrations were monitored and changes in concentration correlated with bacteria development at the initial stage of the process and to fungal development in the latter stages.

Chemical modelling of pore water composition from PFBC residues

International Nuclear Information System (INIS)

Karlsson, L.G.

1991-01-01

The concentration of trace elements varies depending on the source of the coal and also due to the combustion process used. Mercury is one important element among the trace elements in the coal residues, generally recognised as potentially harmful to the biological system. To predict the pore water concentrations of mercury and other important constituents leached from coal combustion residues disposal sites, mechanistic data on chemical reactions are required. The present study is an application of a basially thermodynamical approach using the geochemical code EQ3NR. The presence of discrete solid phases that control the aqueous concentrations of major elements such as aluminium, calcium and silicon are identified. Solid phases are modelled in equilibrium with a hypothetical pore water at a pH range of 7-11. In this study the thermodynamic database of EQ3NR has been complemented with data for cadmium, mercury and lead taken from the OECD/NEA Thermodynamic Database and from a compilation made by Lindsay. Possible solubility limiting phases for the important trace elements arsenic, cadmium, chromium, copper, mercury, nickel and lead have been identified. Concentrations of these trace elements as a function of pH in the hypothetical pore water were calculated using mechanistic thermodynamial data. The thermodynamical approach in this study seems justified because most solid residues that are either present or expected to form during weathering have relatively fast precipitation/dissolution kinetics. (21 refs., 18 figs., 5 tabs.)

Chemical modelling of trace elements in pore water from PFBC residues containing ammonia

International Nuclear Information System (INIS)

Karlsson, L.G.; Brandberg, F.

1993-01-01

Ammonia is added to the PFBC process with the purpose to reduce the emissions of NO x in the stack gases. The design of the system for cleaning the stack gases will lead to an increased adsorption of ammonia and an accumulation of soluble ammonium salts in the cyclone ash from PFBC processes. This can be an environmental problem since the amounts will increase over the coming years and there will be a need to dispose the residues. When infiltrating rainwater penetrates the disposed residues ammonia and ammonium salts result in a contamination of the pore water with ammonia in the disposed residues. This entail the solubility of several trace elements in the residues that form soluble complexes with ammonia will increase and cause an increased contamination of groundwater and surface water. In this study the increased solubilities is calculated for the trace elements cadmium, cobalt, copper, mercury, nickel, silver and zinc in the residues using thermodynamical data. The calculations have been performed with probable solid phases of the trace elements at oxidizing and reducing conditions as a function of pH and at varying concentration of ammonia in the pore water. The thermodynamic calculations have been performed with the geochemical code EQ3NR. The results from the calculations show that as a concentration of 17 mg NH 3 /l in the pore water of the residues increases the solubilities for copper and silver. If the concentration of ammonia increases to 170 mg NH 3 /l will the solubilities increase also for cadmium, nickel and zinc. (12 refs., 39 figs.)

Residual volume on land and when immersed in water: effect on percent body fat.

Science.gov (United States)

Demura, Shinichi; Yamaji, Shunsuke; Kitabayashi, Tamotsu

2006-08-01

There is a large residual volume (RV) error when assessing percent body fat by means of hydrostatic weighing. It has generally been measured before hydrostatic weighing. However, an individual's maximal exhalations on land and in the water may not be identical. The aims of this study were to compare residual volumes and vital capacities on land and when immersed to the neck in water, and to examine the influence of the measurement error on percent body fat. The participants were 20 healthy Japanese males and 20 healthy Japanese females. To assess the influence of the RV error on percent body fat in both conditions and to evaluate the cross-validity of the prediction equation, another 20 males and 20 females were measured using hydrostatic weighing. Residual volume was measured on land and in the water using a nitrogen wash-out technique based on an open-circuit approach. In water, residual volume was measured with the participant sitting on a chair while the whole body, except the head, was submerged . The trial-to-trial reliabilities of residual volume in both conditions were very good (intraclass correlation coefficient > 0.98). Although residual volume measured under the two conditions did not agree completely, they showed a high correlation (males: 0.880; females: 0.853; P body fat computed using residual volume measured in both conditions was very good for both sexes (males: r = 0.902; females: r = 0.869, P body fat: -3.4 to 2.2% for males; -6.3 to 4.4% for females). We conclude that if these errors are of no importance, residual volume measured on land can be used when assessing body composition.

Reactor water quality degradation suppressing method upon reactor start up

International Nuclear Information System (INIS)

Maeda, Katsuharu.

1993-01-01

Preceding to reactor start-up, vacuum degree in a condenser is increased, and after the vacuum degree has been increased sufficiently, a desalting tower is inserted. Then, water feed to the reactor is started and the reactor is operated so that water is supplied gradually. Thus, dissolved oxygen in the feedwater and condensates is kept low and an entire organic carbon leaching rate from resins in the condensate desalting tower is reduced. Further, since feedwater is gradually supplied after the start-up, the entire organic carbon brought into the reactor is decomposed by heat and radiation and efficiently removed by a reactor coolant cleanup system. As a result, corrosion of stainless steel or the like is suppressed, as well as integrity of fuels can be maintained. Further, degradation of water quality can be suppressed effectively not by additionally putting the condensate desalting towers to in-service in accordance with the increase of the feedwater flow rate accompanying the power up but by previously putting the condensate desalting towers to in-service. (N.H.)

Gasification of fruit wastes and agro-food residues in supercritical water

International Nuclear Information System (INIS)

Nanda, Sonil; Isen, Jamie; Dalai, Ajay K.; Kozinski, Janusz A.

2016-01-01

Highlights: • Supercritical water gasification of various fruit wastes and agro-food residues. • Coconut shell had superior carbon content and calorific value due to high lignin. • Maximum H_2 yields at 600 °C with 1:10 biomass-to-water ratio, 45 min and 23–25 MPa. • High H_2 yields from coconut shell, bagasse and aloe vera rind with 2 wt% K_2CO_3. • High CH_4 yields from coconut shell with 2 wt% NaOH due to methanation reaction. - Abstract: Considerable amounts of fruit wastes and agro-food residues are generated worldwide as a result of food processing. Converting the bioactive components (e.g., carbohydrates, lipids, fats, cellulose, hemicellulose and lignin) in food wastes to biofuels is a potential remediation approach. This study highlights the characterization and hydrothermal conversion of several fruit wastes and agro-food residues such as aloe vera rind, banana peel, coconut shell, lemon peel, orange peel, pineapple peel and sugarcane bagasse to hydrogen-rich syngas through supercritical water gasification. The agro-food wastes were gasified in supercritical water to study the impacts of temperature (400–600 °C), biomass-to-water ratio (1:5 and 1:10) and reaction time (15–45 min) at a pressure range of 23–25 MPa. The catalytic effects of NaOH and K_2CO_3 were also investigated to maximize the hydrogen yields and selectivity. The elevated temperature (600 °C), longer reaction time (45 min) and lower feed concentration (1:10 biomass-to-water ratio) were optimal for higher hydrogen yield (0.91 mmol/g) and total gas yield (5.5 mmol/g) from orange peel. However, coconut shell with 2 wt% K_2CO_3 at 600 °C and 1:10 biomass-to-water ratio for 45 min revealed superior hydrogen yield (4.8 mmol/g), hydrogen selectivity (45.8%) and total gas yield (15 mmol/g) with enhanced lower heating value of the gas product (1595 kJ/Nm"3). The overall findings suggest that supercritical water gasification of fruit wastes and agro-food residues could serve as

Determination of potassium concentration in salt water for residual beta radioactivity measurements

International Nuclear Information System (INIS)

Suarez-Navarro, J.A.; Pujol, Ll.

2004-01-01

High interferences may arise in the determination of potassium concentration in salt water. Several analytical methods were studied to determine which method provided the most accurate measurements of potassium concentration. This study is relevant for radiation protection because the exact amount of potassium in water samples must be known for determinations of residual beta activity concentration. The fitting algorithm of the calibration curve and estimation of uncertainty in potassium determinations were also studied. The reproducibility of the proposed analytical method was tested by internal and external validation. Furthermore, the residual beta activity concentration of several Spanish seawater and brackish river water samples was determined using the proposed method

Forecasting the quality of water-suppressed 1 H MR spectra based on a single-shot water scan.

Science.gov (United States)

Kyathanahally, Sreenath P; Kreis, Roland

2017-08-01

To investigate whether an initial non-water-suppressed acquisition that provides information about the signal-to-noise ratio (SNR) and linewidth is enough to forecast the maximally achievable final spectral quality and thus inform the operator whether the foreseen number of averages and achieved field homogeneity is adequate. A large range of spectra with varying SNR and linewidth was simulated and fitted with popular fitting programs to determine the dependence of fitting errors on linewidth and SNR. A tool to forecast variance based on a single acquisition was developed and its performance evaluated on simulated and in vivo data obtained at 3 Tesla from various brain regions and acquisition settings. A strong correlation to real uncertainties in estimated metabolite contents was found for the forecast values and the Cramer-Rao lower bounds obtained from the water-suppressed spectra. It appears to be possible to forecast the best-case errors associated with specific metabolites to be found in model fits of water-suppressed spectra based on a single water scan. Thus, nonspecialist operators will be able to judge ahead of time whether the planned acquisition can possibly be of sufficient quality to answer the targeted clinical question or whether it needs more averages or improved shimming. Magn Reson Med 78:441-451, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Sources of manganese in the residue from a water treatment plant ...

African Journals Online (AJOL)

Disposal of water treatment residue (WTR), the by-product from the production of potable water, has traditionally been to landfill. The shortage of suitable landfill sites has led to the proposal that WTR be applied to land. Such disposal is only possible if the WTR contains no toxic elements that may contaminate soil, water or ...

Numerical modeling of water spray suppression of conveyor belt fires in a large-scale tunnel.

Science.gov (United States)

Yuan, Liming; Smith, Alex C

2015-05-01

Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect.

Numerical modeling of water spray suppression of conveyor belt fires in a large-scale tunnel

Science.gov (United States)

Yuan, Liming; Smith, Alex C.

2015-01-01

Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect. PMID:26190905

Characterization of biomass residues and their amendment effects on water sorption and nutrient leaching in sandy soil.

Science.gov (United States)

Wang, Letian; Tong, Zhaohui; Liu, Guodong; Li, Yuncong

2014-07-01

In this study, we evaluated the efficiency of two types of biomass residues (fermentation residues from a bioethanol process, FB; brown mill residues from a papermaking process, BM) as amendments for a sandy soil. The characteristics of these residues including specific surface areas, morphologies and nutrient sorption capacity were measured. The effects of biorefinery residues on water and nutrient retention were investigated in terms of different particle sizes and loadings. The results indicated that bio-based wastes FB and BM were able to significantly improve water and nutrient retention of sandy soil. The residues with larger surface areas had better water and nutrient retention capability. Specifically, in the addition of 10% loading, FB and BM was able to improve water retention by approximately 150% and 300%, while reduce 99% of ammonium and phosphate concentration in the leachate compare to the soil control, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

Treatment of mine water and solid residues (RS) in San Rafael mining and milling complex

International Nuclear Information System (INIS)

Asenjo, Armando R.; Perrino, Juan F.

2006-01-01

San Rafael Mining and Milling Complex is located in Mendoza Province, in San Rafael Department, 38 km West from San Rafael city and 240 km south from Mendoza city, capital of the province. Activities related with yellow cake production were performed from 1979 to 1999. Nowadays the mine and the plant are in stand by. At the moment technical, economic and environmental studies are being done in order to restart the activities. Different kind of residues are accumulated in the site: a) Tailing; b) Sludges; c) Low grade ores; e) Waste rock; f) Mine water; g) Solid residues (RS). In this paper methodology to treat mine water and solid residues (RS) will be informed. a) Mine water: 800.000 m 3 of mine water are accumulated in different open pit. Uranium, radium and arsenic are the main ions to take into account to treat the water. Several laboratory and pilot test have been performed in order to define the treatment of the water, according with the regulatory requirement. A methodology using anion exchange resin to fix uranium and precipitation using barium chloride and iron sulfate to separate radium and arsenic has been developed. b) Solid residues (RS): these residues (precipitates) have been produced by neutralization of effluents in a nuclear purification process (TBP process). They are accumulated in drums. These residues come from Cordoba plant, a factory which produces UO 2 powder. The total content of uranium in the precipitate is 14.249 kg with an average uranium concentration of 1,33%. A methodology using sulfuric acid dissolution of the precipitates and anion exchange resin to recovery the uranium has been developed. (author) [es

Sloshing of water in torus pressure-suppression pool of boiling water reactors under earthquake ground motions

International Nuclear Information System (INIS)

Aslam, M.; Godden, W.G.; Scalise, D.T.

1978-08-01

This report presents an analytical and experimental investigation into the sloshing of water in torus tanks under horizontal earthquake ground motions. This study was motivated because of the use of torus tanks for pressure-suppression pools in Boiling Water Reactors. Such a pressure-suppression pool would typically have 80 ft and 140 ft inside and outside diameters, a 30 ft diameter section, and a water depth of 15 ft. A general finite element analysis was developed for all axisymmetric tanks and a computer program was written to obtain time-history plots of sloshing displacements of water and dynamic pressures. Tests were carried out on a 1/60th scale model under sinusoidal as well as simulated earthquake ground motions. Tests and analytical results regarding natural frequencies, surface water displacements, and dynamic pressures were compared and a good agreement was found within the range of displacements studied. The computer program gave satisfactory results within a maximum range of sloshing displacements in the full-size prototype of 30 in. which is greater than the value obtained under the full intensity of the El Centro earthquake (N-S component 1940). The range of linear behavior was studied experimentally by subjecting the torus model to increasing intensities of the El Centro earthquake

Identification and quantification of pesticide residues in water samples of Dhamrai Upazila, Bangladesh

Science.gov (United States)

Hasanuzzaman, M.; Rahman, M. A.; Salam, M. A.

2017-10-01

Being agricultural country, different types of pesticides are widely used in Bangladesh to prevent the crop losses due to pest attack which are ultimately drain to the water bodies. The present study was conducted to identify and quantify the organochlorine (DDT, DDE and DDD), organophosphorus (malathion, diazinon and chloropyrifos) and carbamate (carbaryl) residues in water samples of different sources from Dhamrai upazila of Bangladesh using high performance liquid chromatography (HPLC) equipped with ultra violate (UV) detector. Thirty water samples from fish pond, cultivated land and tube-well were collected in winter season to analyze the pesticide residues. Among the organophosphorus pesticides, malathion was present in seven water samples ranging from 42.58 to 922.8 μg/L, whereas diazinon was detected in water sample-8 (WS-8) and the concentration was 31.5 μg/L. None of the tested water samples was found to be contaminated with chlorpyrifos, carbaryl or DDT and its metabolites (DDE and DDD). Except for a tube-well water sample, concentrations of the detected residues are above the acceptable limit for human body as assigned by different organizations. To avoid the possible health hazards, the indiscriminate application of pesticides should be restricted and various substitute products like bio-pesticide should be introduced in a broad scale as soon as possible.

Residual fluxes of water, salt and suspended sediment in the Beypore Estuary

Digital Repository Service at National Institute of Oceanography (India)

AnilKumar, N.; Revichandran, C.; Sankaranarayanan, V.N.; Josanto, V.

The monthly trends of the residual fluxes of salt and water and the transportation of suspended sediments in the Beypore estuarine system, Kerala, India were examined. At the river mouth the water flux was directed seaward during the postmonsoon...

Increasing water intake influences hunger and food preference, but does not reliably suppress energy intake in adults.

Science.gov (United States)

McKay, Naomi J; Belous, Ilona V; Temple, Jennifer L

2018-04-17

Increasing water intake is often purported to reduce energy intake, and is recommended as a weight loss strategy. The few experimental studies that have been conducted to verify these claims have examined the impact of a single pre-load of water before a meal. Although correlational data indicate a relationship between hydration, energy intake, and weight status, there is very little experimental research in this area. The current studies examined the hypothesis that elevated hydration, through increased water intake, would suppress energy intake. In Experiment 1, participants (n = 49) were asked to consume either one, two, or three 500 ml bottles of water throughout the morning before a lunch buffet in the laboratory. When participants categorized as normal weight drank three bottles of water they consumed less energy at lunch, but there was no effect on participants categorized as overweight or obese. In addition, increased water intake suppressed liking of food items in all participants and hunger in females. A follow-up study (n = 45) was conducted to test if four bottles of water throughout the morning would result in a similar energy suppression in participants categorized as overweight or obese. Surprisingly, in the second experiment, there was no effect of water intake on energy intake at lunch in any of the conditions. There was, however, a similar suppression of hunger and food liking. In conclusion, increasing water intake throughout the morning only suppressed energy intake in individuals categorized as normal weight under certain circumstances, and had no effect on individuals categorized as overweight/obese. Copyright © 2018 Elsevier Inc. All rights reserved.

POPULATION DIVERSITY IN MODEL DRINKING WATER BIOFILMS RECEIVING CHLORINE OR MONOCHLORAMINE RESIDUAL

Science.gov (United States)

Most water utilities add monochloramine or chlorine as a residual disinfectant in potable water distribution systems (WDS) to control bacterial regrowth. While monochloramine is considered more stable than chlorine, little is known about the fate of this disinfectant or the effec...

Stabilization of arsenic and chromium polluted soils using water treatment residues

DEFF Research Database (Denmark)

Nielsen, Sanne Skov

water and can be used as a soil amendment to decrease the mobility of CCA in contaminated soil. Stabilization with Fe-WTR was tested at the Collstrop site in Hillerød, Denmark. The site has been polluted with a wide range of wood impregnation agents including CCA during 40 years of wood impregnating...... of contaminants. Arsenic, chromium and copper cannot be degraded and existing methods for cleaning the soil are rarely used as they are expensive and technically demanding. Chemical stabilization of polluted soil is an alternative method for soil remediation, especially metal contamination, and consists in adding...... or other sorbents. Iron water treatment residues mainly consist of ferrihydrite, an oxidized iron oxy-hydroxide with a high reactivity and a large specific surface area with a high capacity for adsorption. Iron water treatment residues (Fe-WTR) are a by-product from treatment of groundwater to drinking...

Residual water treatment for gamma radiation. Tratamiento de aguas residuales por radiacion gamma

Energy Technology Data Exchange (ETDEWEB)

Mendez, L [Universidad Nacional Mayor de San Marcos. Facultad de Quimica (Peru)

1990-07-01

The treatment of residual water by means of gamma radiation for its use in agricultural irrigation is evaluated. Measurements of physical, chemical, biological and microbiological contamination indicators were performed. For that, samples from the treatment center of residual water of San Juan de Miraflores were irradiated up to a 52.5 kGy dose. The study concludes that gamma radiation is effective to remove parasites and bacteria, but not for removal of the organic and inorganic matter. (author). 15 refs., 3 tabs., 4 figs.

Effects of residual stress on irradiation hardening in stainless steels

Energy Technology Data Exchange (ETDEWEB)

Okubo, N.; Kondo, K.; Kaji, Y. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Miwa, Y. [Nuclear Energy and Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Ibaraki-ken (Japan)

2007-07-01

Full text of publication follows: Structural materials in fusion reactor with water cooling system will undergo corrosion in aqueous environment and heavier irradiation than that in LWR. Irradiation assisted stress corrosion (IASCC) may be induced in stainless steels exposed in these environment for a long term of reactor operation. The IASCC is considered to be caused in a welding zone. It is difficult to predict and estimate the IASCC, because several irradiation effects (irradiation hardening, swelling, irradiation induced stress relaxation, etc) work intricately. Firstly, effects of residual stress on irradiation hardening were investigated in stainless steels. Specimens used in this study were SUS316 and SUS316L. By bending deformation, the specimens with several % plastic strain, which corresponds to weld residual stress, were prepared. Ion irradiations of 12 MeV Ni{sup 3+} were performed at 330, 400 and 550 deg. C to 45 dpa in TIARA facility at JAEA. No bent specimen was simultaneously irradiated with the bent specimen. The residual stress was estimated by X-ray residual stress measurements before and after the irradiation. The micro-hardness was measured by using nano-indenter. The irradiation hardening and the stress relaxation were changed by irradiation under bending deformation. The residual stress did not relax even for the case of the higher temperature aging at 500 deg. C for the same time of irradiation. The residual stress after ion irradiation, however, relaxed at these experimental temperatures in SUS316L. The hardness was obviously suppressed in bent SUS316L irradiated at 300 deg. C to 6 or 12 dpa. It was evident that irradiation induced stress relaxation occasionally suppressed the irradiation hardening in SUS316L. (authors)

Insecticide residue monitoring in sediments water fish and mangroves at the Cimanuk Delta

International Nuclear Information System (INIS)

Sumatra, Made

1982-01-01

The water and sediments from the upper stream of Cimanuk river carry insecticide residues especially during the rainy season. The insecticides are deposited in the estuary of Cimanuk river and along the coast of Cimanuk delta. The insecticide residues found at the delta were diazinon thiodan DDE o p-DDT and p p-DDT. Those insecticides are found in most of the water sediments and mangrove leaves samples and some of fishes samples. The samples were taken from the river the estuary the sea, the tambaks, the coast line, and from paddy field. No insecticide residue is found in the water samples taken in the dry season but they are found in the sediment samples taken in both the dry and rainy season. Generally the diazinon residues are higher at the surface than at 0.5m depth in compact sediment but they are higher at 0.5m depth than at the surface of the mud from the coast line. Diazinon and thiodan are found only in three fish samples out of twenty samples analyzed but thiodan is found in almost all of the sediment and mangrove leaves samples. DDT is found in almost all of the samples analyzed. (author)

Remediation of cadmium contaminated water and soil using vinegar residue biochar.

Science.gov (United States)

Li, Yuxin; Pei, Guangpeng; Qiao, Xianliang; Zhu, Yuen; Li, Hua

2018-06-01

This study investigated a new biochar produced from vinegar residue that could be used to remediate cadmium (Cd)-contaminated water and soil. Aqueous solution adsorption and soil incubation experiments were performed to investigate whether a biochar prepared at 700 °C from vinegar residue could efficiently adsorb and/or stabilize Cd in water and soil. In the aqueous solution adsorption experiment, the Cd adsorption process was best fitted by the pseudo-second-order kinetic and Freundlich isotherm models. If the optimum parameters were used, i.e., pH 5 or higher, a biochar dosage of 12 g L -1 , a 10 mg L -1 Cd initial concentration, and 15-min equilibrium time, at 25 °C, then Cd removal could reach about 100%. The soil incubation experiment evaluated the biochar effects at four different application rates (1, 2, 5, and 10% w/w) and three Cd contamination rates (0.5, 1, and 2.5 mg kg -1 ) on soil properties and Cd fractionation. Soil pH and organic matter increased after adding biochar, especially at the 10% application rate. At Cd pollution levels of 1.0 or 2.5 mg kg -1 , a 10% biochar application rate was most effective. At 0.5 mg Cd kg -1 soil, a 5% biochar application rate was most efficient at transforming the acid extractable and easily reducible Cd fractions to oxidizable and residual Cd. The results from this study demonstrated that biochar made from vinegar residue could be a new and promising alternative biomass-derived material for Cd remediation in water and soil.

Cover crop residue management for optimizing weed control

NARCIS (Netherlands)

Kruidhof, H.M.; Bastiaans, L.; Kropff, M.J.

2009-01-01

Although residue management seems a key factor in residue-mediated weed suppression, very few studies have systematically compared the influence of different residue management strategies on the establishment of crop and weed species. We evaluated the effect of several methods of pre-treatment and

Role of iron and aluminum coagulant metal residuals and lead release from drinking water pipe materials.

Science.gov (United States)

Knowles, Alisha D; Nguyen, Caroline K; Edwards, Marc A; Stoddart, Amina; McIlwain, Brad; Gagnon, Graham A

2015-01-01

Bench-scale experiments investigated the role of iron and aluminum residuals in lead release in a low alkalinity and high (> 0.5) chloride-to-sulfate mass ratio (CSMR) in water. Lead leaching was examined for two lead-bearing plumbing materials, including harvested lead pipe and new lead: tin solder, after exposure to water with simulated aluminum sulfate, polyaluminum chloride and ferric sulfate coagulation treatments with 1-25-μM levels of iron or aluminum residuals in the water. The release of lead from systems with harvested lead pipe was highly correlated with levels of residual aluminum or iron present in samples (R(2) = 0.66-0.88), consistent with sorption of lead onto the aluminum and iron hydroxides during stagnation. The results indicate that aluminum and iron coagulant residuals, at levels complying with recommended guidelines, can sometimes play a significant role in lead mobilization from premise plumbing.

Mutational properties of amino acid residues: implications for evolvability of phosphorylatable residues

DEFF Research Database (Denmark)

Creixell, Pau; Schoof, Erwin M.; Tan, Chris Soon Heng

2012-01-01

in terms of their mutational activity. Moreover, we highlight the importance of the genetic code and physico-chemical properties of the amino acid residues as likely causes of these inequalities and uncover serine as a mutational hot spot. Finally, we explore the consequences that these different......; it is typically assumed that all amino acid residues are equally likely to mutate or to result from a mutation. Here, by reconstructing ancestral sequences and computing mutational probabilities for all the amino acid residues, we refute this assumption and show extensive inequalities between different residues...... mutational properties have on phosphorylation site evolution, showing that a higher degree of evolvability exists for phosphorylated threonine and, to a lesser extent, serine in comparison with tyrosine residues. As exemplified by the suppression of serine's mutational activity in phosphorylation sites, our...

Pressure suppressing device

International Nuclear Information System (INIS)

Naito, Makoto.

1980-01-01

Purpose: To prevent the pressure in the reactor container from excessively increasing even when vapor leaks from the dry well to a space of the suppression chamber, without passing though the suppression pool at the time of loss of coolant accident. Constitution: When vapor of a high temperature and a high pressure at the time of loss of coolant accident flows from the dry well to the suppression chamber without passing through suppression pool water, vapor dose not condense with pool water, and therefore the pressure within the chamber abnormally increases. For this reason, this abnormal pressure is detected by a pressure detector thereby to start the operations of a blower and a pump. By starting the blower, the pressure in the dry well becomes lower than the pressure in the chamber, and vapor entirely passes through the pool water and entirely condenses with the pool water. By starting the pump, the pool water is sprayed over the space of the chamber, and vapor in the space is condensed. (Yoshino, Y.)

Volatile suppressing method for radioactive iodine

International Nuclear Information System (INIS)

Ohara, Atsushi; Haruguchi, Keiko.

1997-01-01

In the present invention, a metal plate is disposed above the pool water surface of a suppression chamber disposed to a reactor container in order to reduce evaporation of radioactive iodine released from a suppression pool. A metal plate is disposed above the pool water surface of the suppression chamber disposed to the reactor container. In addition, a metal plate is disposed around the space connecting a bent tube extending from a dry well to underwater of suppression pool water and a gas bent tube extending from the suppression chamber to an emergency gas processing system. Spray water is supplied for cooling the suppression chamber d as a means for cooling the metal plate. Then, among iodine released to the suppression chamber, elemental iodine liberated from the pool water is deposited on the surface of the metal plate, and the amount of iodine to be flown into and processed by an emergency gas processing system or a filter bent system can be reduced. (T.M.)

Some techniques used in the treatment of phenolic waters residual

International Nuclear Information System (INIS)

Alzate S, Rafael A.; Botero, Carlos Andre

2000-01-01

The current state of the diverse processes of treatment of phenolic waters residual is presented, beginning with the methods traditionally employees, until finishing with those but recent innovations, which have been derived of the necessity of increasing the removal of these pollutants without increasing the costs of such processes in excessive form

Estimation of the residual bromine concentration after disinfection of cooling water by statistical evaluation.

Science.gov (United States)

Megalopoulos, Fivos A; Ochsenkuehn-Petropoulou, Maria T

2015-01-01

A statistical model based on multiple linear regression is developed, to estimate the bromine residual that can be expected after the bromination of cooling water. Make-up water sampled from a power plant in the Greek territory was used for the creation of the various cooling water matrices under investigation. The amount of bromine fed to the circuit, as well as other important operational parameters such as concentration at the cooling tower, temperature, organic load and contact time are taken as the independent variables. It is found that the highest contribution to the model's predictive ability comes from cooling water's organic load concentration, followed by the amount of bromine fed to the circuit, the water's mean temperature, the duration of the bromination period and finally its conductivity. Comparison of the model results with the experimental data confirms its ability to predict residual bromine given specific bromination conditions.

Residual stress improved by water jet peening using cavitation for small-diameter pipe inner surfaces

International Nuclear Information System (INIS)

Yasuo, Nakamura; Toshizo, Ohya; Koji, Okimura

2001-01-01

As one of degradation conditions on components used in water, the overlapping effect of environment, material and stress might cause stress corrosion cracking (SCC). Especially, for the tensile residual stress produced by welding, it is particularly effective to reduce the tensile residual stress on the material surface to prevent SCC. In this paper, the residual stress improvement method using cavitation impact generated by a water jet, called Water Jet Peening (WJP), has been developed as the maintenance technology for the inner surfaces of small-diameter Ni-Cr-Fe alloy (Alloy 600) pipes. As the results, by WJP for the inner surface of Alloy 600 pipe (inner diameter; approximately 10-15 mm), we confirmed that the compressive stress generated within the range from the surface to the inner part about 0.5 mm deep and took a maximum value about 350 MPa on the surface. (author)

Effect of residual water content on the physico-chemical properties of sucralfate dried gel obtained by microwave drying.

Science.gov (United States)

Gainotti, Alessandro; Losi, Elena; Bettini, Ruggero; Colombo, Paolo; Sonvico, Fabio; Baroni, Daniela; Santi, Patrizia; Colombo, Gaia

2005-08-01

The purpose of this study was to investigate the physico-chemical characteristics of sucralfate humid gel dried by microwaves, in relation to the residual water content. Differential scanning calorimetry (DSC) allowed for the determination of the water state in sucralfate samples. Fourier-transform infrared (FT-IR) spectroscopy was used to monitor the changes in sucralfate gel structure induced by the microwave drying. A boundary value of total water content for sucralfate gel samples was found at 42% (w/w). Below this value only bound water was present, whereas above this value, the increase in total water was due to free water. In the physical form of gel, the strength of the coordination between sulfate anions and the positively charged aluminum hydroxide was dependent on the residual water content. The study of the sedimentation behavior of water suspensions prepared with dried sucralfate allowed for the evaluation of the retention of gel properties. We found that the microwave drying process affected the sedimentation of sucralfate dried gel suspensions independent of the residual water content: when suspensions were prepared from sucralfate dried gel powders containing more than 42% (w/w) of residual water, the sedimentation ratio was higher than 0.9. The non-gel powder suspension showed a sedimentation ratio of 0.68 +/- 0.02, whereas the sucralfate humid gel suspension did not sediment.

Impacts of channel morphology on residues and ecological risks of polychlorinated biphenyls in water and sediment in Chahe River

Directory of Open Access Journals (Sweden)

Zhen-hua Zhao

2016-10-01

Full Text Available The impacts of channel morphology on the residues and ecological risks of 14 polychlorinated biphenyl (PCB congeners in water and sediment were investigated in summer (July and autumn (September in the Chahe River, in Nanjing, China. The residual concentrations of tri-chlorobiphenyls (tri-CBs, PCB 18 and tetra-CBs (PCB 52 in water were significantly higher than those of penta-CBs to deca-CBs, and the average residual concentration of ∑PCBs (sum of 14 PCB congeners in summer was about six times higher than in autumn. However, the residues in sediment did not change significantly. Redundancy analysis (RDA indicated that channel morphology and the corresponding environmental indices had significant impacts on PCB residues and their composition profiles in water and sediment. The overflow weir and lake-type watercourse may remarkably reduce the residual concentration and ecological risks of PCBs in water. The highest reduction percentages of the residual concentration and ecological risks of ∑PCBs induced by an overflow weir were 78% and 67%, respectively, and those induced by a lake-type watercourse were 36% and 70%, respectively. The watercourses with different channel morphologies were ranked by residual ∑PCBs concentrations in the following descending order: the natural ecological watercourse, vertical concrete watercourse, and vegetation-type riprap watercourse. However, they were ranked by residual ∑PCBs concentrations in sediment in the following descending order: the vertical concrete watercourse, vegetation-type riprap watercourse, and natural ecological watercourse.

Polar drug residues in sewage and natural waters in the state of Rio de Janeiro, Brazil.

Science.gov (United States)

Stumpf, M; Ternes, T A; Wilken, R D; Rodrigues, S V; Baumann, W

1999-01-12

The drug residues of lipid regulators, anti-inflammatories and some drug metabolites have been detected in raw sewage, treated waste water and river water in the state of Rio de Janeiro, Brazil. These residues are mainly derived from humans via excretion. The median concentrations in the effluents of sewage treatment plants (STPs) of most drugs investigated in this study ranged from 0.1 to 1 microgram/l. The removal rates of individual drugs during passage through a Brazilian STP varied from 12 to 90%. As a consequence of the incomplete removal of these residues during passage through a STP, rivers were also found to be contaminated. Median concentrations ranged from between 0.02 and 0.04 microgram/l in river water, whereas the maximum values were observed to be up to 0.5 microgram/l.

Napropamide residues in runoff and infiltration water from pepper production.

Science.gov (United States)

Antonious, George F; Patterson, Matthew A

2005-01-01

A field study was conducted on a Lowell silty loam soil of 2.7% organic matter at the Kentucky State University Research Farm, Franklin County, Kentucky. Eighteen universal soil loss equation (USLE) standard plots (22 x 3.7 m each) were established on a 10% slope. Three soil management practices were used: (i) class-A biosolids (sewage sludge), (ii) yard waste compost, each mixed with native soil at a rate of 50 ton acre(-1) on a dry-weight basis, and (iii) a no-mulch (NM) treatment (rototilled bare soil), used for comparison purposes. Devrinol 50-DF "napropamide" [N,N-diethyl-2-(1-naphthyloxy) propionamide] was applied as a preemergent herbicide, incorporated into the soil surface, and the plots were planted with 60-day-old sweet bell pepper seedlings. Napropamide residues one hour following spraying averaged 0.8, 0.4, and 0.3 microg g(-1) dry soil in sewage sludge, yard waste compost, and no-mulch treatments, respectively. Surface runoff water, runoff sediment, and napropamide residues in runoff were significantly reduced by the compost and biosolid treatments. Yard waste compost treatments increased water infiltration and napropamide residues in the vadose zone compared to sewage sludge and NM treatments. Total pepper yields from yard waste compost amended soils (9187 lbs acre(-1)) was significantly higher (P soil amended with class-A biosolids (6984 lbs acre(-1)) or the no-mulch soil (7162 lbs acre(-1)).

Mitigation of dimethazone residues in soil and runoff water from agricultural field.

Science.gov (United States)

Antonious, George F

2011-01-01

Dimethazone, also known as clomazone [2-[(2-chlorophenyl) methyl]- 4,4-dimethyl-3-isoxaolidinone] is a pre-emergent nonionic herbicide commonly used in agriculture. A field study was conducted on a silty-loam soil of 10 % slope to monitor off-site movement and persistence of dimethazone in soil under three management practices. Eighteen plots of 22 x 3.7 m each were separated using stainless steel metal borders and the soil in six plots was mixed with municipal sewage sludge (MSS) and yard waste (YW) compost (MSS+YW) at 15 t acre⁻¹ on dry weight basis, six plots were mixed with MSS at 15 t acre⁻¹, and six unamended plots (NM) were used for comparison purposes. The objectives of this investigation were to: (i) monitor the dissipation and half-life (T₁/₂) of dimethazone in soil under three management practices; (ii) determine the concentration of dimethazone residues in runoff and infiltration water following natural rainfall events; and (iii) assess the impact of soil amendments on the transport of NO₃, NH₄, and P into surface and subsurface water. Gas chromatography/mass spectrometery (GC/MS) analyses of soil extracts indicated the presence of ion fragments at m/z 125 and 204 that can be used for identification of dimethazone residues. Intitial deposits of dimethazone varied from 1.3 μg g⁻¹ dry native soil to 3.2 and 11.8 μg g⁻¹ dry soil in MSS and MSS+YW amended soil, respectively. Decline of dimethazone residues in the top 15 cm native soil and soil incorporated with amendments revealed half-life (T₁/₂) values of 18.8, 25.1, and 43.0 days in MSS+YW, MSS, and NM treatments, respectively. Addition of MSS+YW mix and MSS alone to native soil increased water infiltration, lowering surface runoff water volume and dimethazone residues in runoff following natural rainfall events.

Instrumenting a pressure suppression experiment for a MK I boiling water reactor: another measurements engineering challenge

International Nuclear Information System (INIS)

Shay, W.M.; Brough, W.G.; Miller, T.B.

1977-01-01

A scale test facility of a pressure suppression system from a boiling water reactor was instrumented with seven types of transducers to obtain high-accuracy experimental data during a hypothetical loss-of-coolant accident. The instrumentation verified the analysis of the dynamic loading of the pressure suppression system

Computed distributions of residual shaft drilling and drift construction water in the exploratory facilities at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Eaton, R.R.; Peterson, A.C.

1990-01-01

This paper contains the results of engineering analytical calculations of the potential distribution of residual construction water in the exploratory shafts and drifts and numerical calculations of the movement of the residual water and how the movement is affected by drift ventilation. Rock saturation is addressed

Impact of recharge through residual oil upon sampling of underlying ground water

International Nuclear Information System (INIS)

Wise, W.R.; Chang, Chichung; Klopp, R.A.; Bedient, P.B.

1991-01-01

At an aviation gasoline spill site in Traverse City, Michigan, historical records indicate a positive correlation between significant rainfall events and increased concentrations of slightly soluble organic compounds in the monitoring wells of the site. To investigate the recharge effect on ground water quality due to infiltrating water percolating past residual oil and into the saturated zone, an in situ infiltration experiment was performed at the site. Sampling cones were set at various depths below a circular test area, 13 feet (4 meters) in diameter. Rainfall was simulated by sprinkling the test area at a rate sufficiently low to prevent runoff. The sampling cones for soil-gas and ground water quality were installed in the unsaturated and saturated zones to observed the effects of the recharge process. Infiltrated water was determined to have transported organic constituents of the residual oil, specifically benzene, toluene, ethylbenzene, and ortho-xylene (BTEX), into the ground water beneath the water table, elevating the aqueous concentrations of these constituents in the saturated zone. Soil-gas concentrations of the organic compounds in the unsaturated zone increased with depth and time after the commencement of infiltration. Reaeration of the unconfined aquifer via the infiltrated water was observed. It is concluded that water quality measurements are directly coupled to recharge events for the sandy type of aquifer with an overlying oil phase, which was studied in this work. Ground water sampling strategies and data analysis need to reflect the effect of recharge from precipitation on shallow, unconfined aquifers where an oil phase may be present

Control system of an anaerobia reactor used in the treatment of the Industrial residual waters

International Nuclear Information System (INIS)

Duque, Mauricio; Giraldo, Eugenio; Bello Frank

1995-01-01

The technology of the anaerobia digestion, has had a wide acceptance in the Colombian means for the treatment of industrial residual waters, especially for the economic advantages that it present and the good purification results. The technology of the anaerobia digestion for the treatment of residual waters, is based in the conversion of the organic matter present in the polluted waters, in methane and carbon dioxide. These two gases are removed of the reactor by means of special structures of gathering. Microorganisms that are sensitive to the changes of the pH mediate the conversion of the organic matter to CH4 and CO2. Therefore, the control on the pH is necessary for a correct behavior of the reactor. At the moment many industries are implementing plans of contamination control, that involve treatment of residual waters for means anaerobia. The present investigation is part of a wide work program in the technology of the anaerobia digestion. It is looked for to develop a monitored system and automatic control of reactors discharge anaerobia appraises, in a combined effort among the departments of Civil and Electric Engineering of the Andes University

Water fluxes in maize, millet and soybean plant-residue mulches used in direct seeding

International Nuclear Information System (INIS)

Silva, Fernando Antonio Macena da; Pinto, Hilton Silveira; Scopel, Eric; Corbeels, Marc; Affholder, Francois

2006-01-01

The objective of this work was to evaluate the effects of crop residue mulches from maize, millet and soybean on water storage capacity, water evaporation, soil cover, solar radiation interception and surface water run-off as well as to incorporate these effects in a crop growth model. The mulch of millet and maize presented higher capacity for water storage than soybean mulch: 3.26, 3.24 and 2.62 g of water per gram of dry matter, respectively. Water losses from wet mulches were related to the potential evapotranspiration. The soil cover levels were similar among the three types of material. The three types of mulch intercepted similar quantities of photosynthetically active radiation and infrared radiation. The mulch of maize straw was slightly more efficient in intercepting radiation than that from millet or soybean. Mulching with millet residues was efficient in the control of surface water run-off: only 45.5 mm of water (out of 843.5 mm rainfall) was lost through runoff under the no-till system with millet as cover crop, whereas 222.5 mm of water was lost in the conventional system with tillage. Most of the relations derived in this work could be described by exponential models. (author)

Exploration of factors influencing shimming and water suppression on hepatic 1H-MR spectroscopy in vivo on 3.0 T

International Nuclear Information System (INIS)

Liang Changhong; Xu Li; Liu Zaiyi; Cui Yanhai; Liu Chunling; Zheng Junhui; Zeng Qiongxin

2009-01-01

Objective: To characterize the clinical factors which influence water suppression and auto-shimming line width for liver 3.0 T 1 H-MRS. Methods: Fifty-seven cases with liver 1 H-MR spectroscopy ( 1 H-MRS) were retrospectively studied, including chronic type B hepatitis (n=5), fatty liver (n=14), chronic type B hepatitis combining fatty liver (n=3) and normal situation (n=35). Independent t test was used to characterize the difference of general condition (height, weight, body mass index etc.) between different water suppression effect groups and between different shimming effect groups. Using Chi-square test to analyze whether water suppression rate and auto-shimming line width between fatty liver groups and non-fatty liver exist significance difference. Results: By comparing WS ≥90% (n=47) group with WS 2 respectively] and LW [(17.7±3.7) and (24.6±6.3) Hz respectively] than the latter (t=-3.488, -3.415, -4.002 and -3.327, P 20 Hz (n=16) group, the former showed better water suppression rate [(93.0±2.7)% and (86.1±8.5)% respectively] than the latter (t=3.213, P 2 respectively] (t=-2.516, -2.024, P 2 =11.347, P 2 =28.536, P<0.05). Conclusion: Hepatic steatosis exerts an adverse effect in water suppression and shimming. (authors)

Verification of an optimized condition for low residual stress employed water-shower cooling during welding in austenitic stainless steel plates

International Nuclear Information System (INIS)

Yanagida, N.; Enomoto, K.; Anzai, H.

2004-01-01

To reduce tensile residual stress in a welded region, we have developed a new cooling method that uses a water-shower behind the welding torch. When this method is applied to the welding of austenitic stainless steel, the welding and cooling conditions mainly determine how much the residual stress can be reduced. To optimize these conditions, we first used a robust design method to determine the effects of the preheating temperature, the heat input quantity, and the water-shower area on the residual stress, and found that, to decrease the tensile residual stress, the preheating temperature should be high, the heat input low, and the water-shower area large. To confirm the effectiveness of these optimized conditions, the residual stresses under optimized or non-optimized conditions were measured experimentally. It was found that the residual stresses were tensile under the non-optimized conditions, but compressive under the optimized ones. These measurements agree well with the 3D-FEM analyses. It can therefore be concluded that the optimized conditions are valid and appropriate for reducing residual stress in an austenitic stainless-steel weld. (orig.)

Experimental determination of residual stress by neutron diffraction in a boiling water reactor core shroud

International Nuclear Information System (INIS)

Payzant, A.; Spooner, S.; Zhu, Xiaojing; Hubbard, C.R.

1996-01-01

Residual strains in a 51 mm (2-inch) thick 304L stainless steel plate have been measured by neutron diffraction and interpreted in terms of residual stress. The plate, measuring (300 mm) in area, was removed from a 6m (20-ft.) diameter unirradiated boiling water reactor core shroud, and included a multiple-pass horizontal weld which joined two of the cylindrical shells which comprise the core shroud. Residual stress mapping was undertaken in the heat affected zone, concentrating on the outside half of the plate thickness. Variations in residual stresses with location appeared consistent with trends expected from finite element calculations, considering that a large fraction of the residual hoop stress was released upon removal of the plate from the core shroud cylinder

Aging assessment of Residual Heat Removal systems in Boiling Water Reactors

International Nuclear Information System (INIS)

Lofaro, R.J.; Aggarwal, S.

1992-01-01

The effects of aging on Residual Heat Removal systems in Boiling Water Reactors have been studied as part of the Nuclear Plant Aging Research Program. The aging phenomena has been characterized by analyzing operating experience from various national data bases. In addition, actual plant data was obtained to supplement and validate the data base findings

Benchmark enclosure fire suppression experiments - phase 1 test report.

Energy Technology Data Exchange (ETDEWEB)

Figueroa, Victor G.; Nichols, Robert Thomas; Blanchat, Thomas K.

2007-06-01

A series of fire benchmark water suppression tests were performed that may provide guidance for dispersal systems for the protection of high value assets. The test results provide boundary and temporal data necessary for water spray suppression model development and validation. A review of fire suppression in presented for both gaseous suppression and water mist fire suppression. The experimental setup and procedure for gathering water suppression performance data are shown. Characteristics of the nozzles used in the testing are presented. Results of the experiments are discussed.

Power flattening and reactivity suppression strategies for the Canadian supercritical water reactor concept

International Nuclear Information System (INIS)

McDonald, M.; Colton, A.; Pencer, J.

2015-01-01

The Canadian supercritical water-cooled reactor (SCWR) is a conceptual heavy water moderated, supercritical light water cooled pressure tube reactor. In contrast to current heavy water power reactors, the Canadian SCWR will be a batch fuelled reactor. Associated with batch fuelling is a large beginning-of-cycle excess reactivity. Furthermore, radial power peaking arising as a consequence of batch refuelling must be mitigated in some way. In this paper, burnable neutron absorber (BNA) added to fuel and absorbing rods inserted into the core are considered for reactivity management and power flattening. A combination of approaches appears adequate to reduce the core radial power peaking, while also providing reactivity suppression. (author)

Usefulness of MR angiography with fat- and water-suppression technique

International Nuclear Information System (INIS)

Ohta, Fumihito; Kagawa, Takato; Kawamitsu, Hideaki; Fukuma, Atsushi; Nagao, Seiichi; Takaya, Mikio; Kimura, Reishin; Yamasaki, Toshiki; Moritake, Kouzo

1994-01-01

The purpose of this study was to improve visualization of intracranial vessels by the use of time-of-flight MR angiography with the fat- and water-suppression technique (TOF-MRA-presat). Two groups of individuals were studied. They were 35 patients with ischemic cerebrovascular disorders (lacunar group) and 22 volunteers (control group). TOF-MRA-presat suppressed the signal of the background tissue, including fat and brain parenchyma. The contrast between background tissue and blood vessels was thus improved. The visibility of the ophthalmic artery, the posterior communicating artery, and the superior cerebellar artery in the control group increased noticeably in the TOF-MRA-presat images as compared with the TOF-MRA images. Similarly, the visibility of the insular segment of the middle cerebral artery, the posterior temporal artery, and the calcarine artery in the lacunar group was also better in TOF-MRA-presat images than in TOF-MRA-images. These results indicate that TOF-MRA-presat dose improve the visualization of intracranial vessels. (author)

Disposing of coal combustion residues in inactive surface mines: Effects on water quality

International Nuclear Information System (INIS)

Kim, A.G.; Ackman, T.E.

1994-01-01

The disposal of coal combustion residues (CCR) in surface and underground coal mines can provide a stable, low-maintenance alternative to landfills, benefiting the mining and electric power industries. The material may be able to improve water quality at acid generating abandoned or reclaimed coal mine sites. Most combustion residues are alkaline, and their addition to the subsurface environment could raise the pH, limiting the propagation of pyrite oxidizing bacteria and reducing the rate of acid generation. Many of these CCR are also pozzolanic, capable of forming cementitious grouts. Grouts injected into the buried spoil may decrease its permeability and porosity, diverting water away from the pyritic material. Both mechanisms, alkaline addition and water diversion, are capable of reducing the amount of acid produced at the disposal site. The US Bureau of Mines is cooperating in a test of subsurface injection of CCR into a reclaimed surface mine. Initially, a mixture of fly ash, lime, and acid mine drainage (AMD) sludge was injected. Lime was the source of calcium for the formation of the pozzolanic grout. Changes in water quality parameters (pH, acidity, anions, and trace metals) in water samples from wells and seeps indicate a small but significant improvement after CCR injection. Changes in the concentration of heavy metals in the water flowing across the site were apparently influenced by the presence of flyash

Novel Approach for Enhanced Scandium and Titanium Leaching Efficiency from Bauxite Residue with Suppressed Silica Gel Formation.

Science.gov (United States)

Alkan, Gözde; Yagmurlu, Bengi; Cakmakoglu, Seckin; Hertel, Tobias; Kaya, Şerif; Gronen, Lars; Stopic, Srecko; Friedrich, Bernd

2018-04-04

The need of light weight alloys for future transportation industry puts Sc and Ti under a sudden demand. While these metals can bring unique and desired properties to alloys, lack of reliable sources brought forth a supply problem which can be solved by valorization of the secondary resources. Bauxite residue (red mud), with considerable Ti and Sc content, is a promising resource for secure supply of these metals. Due to drawbacks of the direct leaching route from bauxite residue, such as silica gel formation and low selectivity towards these valuable metals, a novel leaching process based on oxidative leaching conditions, aiming more efficient and selective leaching but also considering environmental aspects via lower acid consumption, was investigated in this study. Combination of hydrogen peroxide (H 2 O 2 ) and sulfuric acid (H 2 SO 4 ) was utilized as the leaching solution, where various acid concentrations, solid-to-liquid ratios, leaching temperatures and times were examined in a comparative manner. Leaching with 2.5 M H 2 O 2 : 2.5 M H 2 SO 4 mixture at 90 °C for 30 min was observed to be the best leaching conditions with suppressed silica gel formation and the highest reported leaching efficiency with high S/L ratio for Sc and Ti; 68% and 91%; respectively.

Optimization of immunochemistry for sensing techniques to detect pesticide residues in water

DEFF Research Database (Denmark)

Uthuppu, Basil; Kostesha, Natalie; Jakobsen, Mogens Havsteen

2011-01-01

We are working on the development of a real-time electrochemical sensor based on an immunoassay detection system to detect and quantify the presence of pesticide residues in ground water. Highly selective and sensitive immuno-reactions are being investigated to be optimized in order to bring them...

Mitigation of inside surface residual stress of type 304 stainless steel pipe welds by inside water cooling method

International Nuclear Information System (INIS)

Sasaki, R.

1980-01-01

The weld residual stress distributions, macro- and microstructures of heat affected zone and IGSCC susceptibility of Type 304 stainless steel pipe welds by natural and inside water cooling methods have been investigated. The residual stresses of pipe welds by the natural cooling method are high tensile on both the inside and the outside surface. While the residual stresses on the inside surface of pipe welds by the inside water cooling method are compressive in both axial and circumferential directions for each pipe size from 2 to 24 inch diameter. The sensitized zones of welds by the inside water cooling method are closer to the fusion line, much narrower and milder than those by the natural cooling method. According to the constant extension rate test results for specimens taken from the inside surface of pipe welds, the inside water cooled welds are more resistant to IGSCC than naturally cooled ones

Computed distributions of residual shaft drilling and construction water in the exploratory facilities at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Eaton, R.R.; Peterson, A.C.

1989-01-01

The Yucca Mountain Project is studying the feasibility of constructing a high-level nuclear waste repository at Yucca Mountain in southwest Nevada. One activity of site characterization is the construction of two exploratory shafts. This paper contains the results of engineering analytical calculations of the potential distribution of residual construction water in the exploratory shafts and drifts and numerical calculations of the movement of the residual water and how the movement is affected by drift ventilation. In all cases the increase in rock saturation resulting from the construction water was extremely small. 11 refs., 15 figs., 1 tab

A method for the determination of residual beta activity in drinking water samples

Energy Technology Data Exchange (ETDEWEB)

Idoeta, R. [Dpto. Ingenieria Nuclear y Mecanica de Fluidos, E. T. S. Ingenieria de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n. 48013 Bilbao (Spain)], E-mail: raquel.idoeta@ehu.es; Herranz, M.; Abelairas, A.; Legarda, F. [Dpto. Ingenieria Nuclear y Mecanica de Fluidos, E. T. S. Ingenieria de Bilbao - Universidad del Pais Vasco (UPV/EHU), Alda. Urquijo s/n. 48013 Bilbao (Spain)

2007-09-15

The determination of residual beta activity in drinking water is usually needed in most monitoring programs. In this work a procedure for its determination is described and expressions for the calculations of detection limits and uncertainties are proposed.

A method for the determination of residual beta activity in drinking water samples

International Nuclear Information System (INIS)

Idoeta, R.; Herranz, M.; Abelairas, A.; Legarda, F.

2007-01-01

The determination of residual beta activity in drinking water is usually needed in most monitoring programs. In this work a procedure for its determination is described and expressions for the calculations of detection limits and uncertainties are proposed

Pressure suppression facility for reactor container

International Nuclear Information System (INIS)

Fujii, Tadashi; Fukui, Toru; Kataoka, Yoshiyuki; Tominaga, Kenji.

1993-01-01

In a nuclear reactor comprising heat transfer surfaces from a pressure suppression pool at the inside to the outer circumferential pool at the outside, a means for supplying water from a water supply source at the outside of the container to the pools is disposed. Then, a heat transfer means is disposed between the pressure suppression chamber and the water cooling pool. The water supply means comprises a pressurization means for applying pressure to water of the water supply source and a water supply channel. Water is supplied into the pressure suppression pool and the outer circumferential pool to elevate the water level and extend the region of heat contact with the water cooling heat transfer means. In addition, since dynamic pressure is applied to the feedwater, for example, by pressurizing the water surface of the water supply source, water can be supplied without using dynamic equipments such as pumps. Then, since water-cooling heat transfer surface can be extended after occurrence of accident, enlargement of a reactor container and worsening of earthquake proofness can be avoided as much as possible, to improve function for suppressing the pressure in the container. Further, since water-cooling heat transfer region can be extended, the arrangement of the water source and the place to which water is supplied is made optional without considering the relative height therebetween, to improve earthquake proofness. (N.H.)

Tetracycline residues in porcine stomach after administration via drinking water on a swine farm.

Science.gov (United States)

Lindquist, Danielle; Wu, Huali; Mason, Sharon; Yeatts, Jim; Brooks, Jim; Barlow, Beth; Schill, Kaitlyn; Baynes, Ronald

2014-01-01

Tetracycline is a broad-spectrum antibiotic used to treat infections in swine. The maximum residue levels of tetracycline in pork stomach tissue in Russia, Europe, and the United States are 10, 200, and 2,000 ppb, respectively. This difference in accepted safety levels may be the reason why stomach tissues that the United States exports continue to be residue violators in overseas markets. In this study, 30 pigs at two different stages of production (weanling and finisher) were treated with tetracycline at 22 mg/kg of body weight per day for a total of 5 days via a water medicator. Blood samples were collected at 0, 72, 78, 96, and 102 h after the start of medication. The medication was stopped at 120 h, and blood samples were again collected at 126, 144, 168, 192, and 216 h after exposure. Five animals were slaughtered for stomach tissue 0, 24, 48, 96, and 192 h after the drug was flushed from the water line. All blood and tissue samples were analyzed by high-performance liquid chromatography-UV methods. The tetracycline levels in plasma were below the level of detection after the U.S.-labeled withdrawal time of 4 days. The stomach tissue residues averaged 671.72, 330.31, 297.77, 136.36, and 268.08 ppb on withdrawal days 0, 1, 2, 4, and 8, respectively. Using the U.S. Food and Drug Administration tolerance limit method and a population-based pharmacokinetic model with Monte Carlo simulation, a withdrawal interval was estimated. This study demonstrated that tetracycline residues are still detectable in the stomach tissues after the established United States withdrawal time of 4 days. These residue levels may explain why stomach tissues tested in Russia and Europe show positive residues for tetracycline, even though the meat may pass inspection here in the United States prior to export.

Effects of Contrast Agent and Outer Volume Saturation Bands on Water Suppression and Shimming of Hepatic Single-Volume Proton MR Spectroscopy at 3.0T

Directory of Open Access Journals (Sweden)

Li Xu

2012-01-01

Full Text Available Purpose. To determine whether administration of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA and whether placement of the outer volume saturation bands significantly affect shimming and water suppression on hepatic MR spectroscopic prescanning. Method. Region of interest (ROI of 2 cm × 2 cm × 2 cm was carefully positioned in the region of the middle portion of the right hepatic lobe. 32 patients were examined before and after administration of Gd-DTPA with and without outer-volume saturation bands. Linewidths (Full-Width Half-Maximum (FWHM and water suppression were obtained. A paired t-test for comparison of means was used. Results. (1 The group with the outer volume saturation bands demonstrated slightly better water suppression effect than the group without outer volume saturation bands before administration. (2 The group with the outer volume saturation bands demonstrated better water suppression effect than the group without outer volume saturation bands after administration. (3 Both shimming and water suppression effectswere decreased on enhanced MR spectroscopic prescanning (all P<0.05. Conclusions. Placement of the outer volume saturation bands is helpful to improve water suppression both before and after contrast agent administration. Gd-DTPA exerts a slightly adverse effect (a statistically significant but clinically unimportant on magnetic resonance spectroscopic prescanning at 3T.

Novel Americium Treatment Process for Surface Water and Dust Suppression Water

International Nuclear Information System (INIS)

Tiepel, E.W.; Pigeon, P.; Nesta, S.; Anderson, J.

2006-01-01

-241 contaminated pond water, surface run-off and D and D dust suppression water during the later stages of the D and D effort at Rocky Flats. This novel chemical treatment system allowed for highly efficient, high-volume treatment of all contaminated waste waters to the very low stream standard of 0.15 pCi/1 with strict compliance to the RFCA discharge criteria for release to off-site surface waters. The rapid development and implementation of the treatment system avoided water management issues that would have had to be addressed if contaminated water had remained in Pond A-4 into the Spring of 2005. Implementation of this treatment system for the Pond A-4 waters and the D and D waters from Buildings 776 and 371 enabled the site to achieve cost-effective treatment that minimized secondary waste generation, avoiding the need for expensive off-site water disposal. Water treatment was conducted for a cost of less than $0.20/gal which included all development costs, capital costs and operational costs. This innovative and rapid response effort saved the RFETS cleanup program well in excess of $30 million for the potential cost of off-site transportation and treatment of radioactive liquid waste. (authors)

Assessing fear following retrieval+extinction through suppression of baseline reward seeking vs. freezing

Directory of Open Access Journals (Sweden)

Jason eShumake

2015-12-01

Full Text Available Freezing has become the predominant measure used in rodent studies of conditioned fear, but conditioned suppression of reward-seeking behavior may provide a measure that is more relevant to human anxiety disorders; that is, a measure of how fear interferes with the enjoyment of pleasurable activities. Previous work has found that an isolated presentation of a fear conditioned stimulus prior to extinction training (retrieval + extinction results in a more robust and longer-lasting reduction in fear. The objective of this study was to assess whether the retrieval + extinction effect is evident using conditioned suppression of reward seeking, operationalized as a reduction in baseline licking (without prior water deprivation for a 10% sucrose solution. We found that, compared to freezing, conditioned suppression of reward seeking was much more sensitive to fear conditioning and far less responsive to extinction training. As in previous work, we found that retrieval + extinction reduced post-extinction fear reinstatement when measured as freezing, but it did not reduce fear reinstatement when measured as conditioned suppression. This suggests that there is still residual fear following retrieval + extinction, or that this procedure only modifies memory traces in neural circuits relevant to the expression of freezing, but not to the suppression of reward seeking.

Ion energy recovery experiment based on magnetic electro suppression

International Nuclear Information System (INIS)

Kim, J.; Stirling, W.L.; Dagenhart, W.K.; Barber, G.C.; Ponte, N.S.

1980-05-01

A proof-of-principle experiment on direct recovery of residual hydrogen ions based on a magnetic electron suppression scheme is described. Ions extracted from a source plasma a few kilovolts above the ground potential (approx. 20 A) are accelerated to 40 keV by a negative potential maintained on a neutralizer gas cell. As the residual ions exit the gas cell, they are deflected from the neutral beam by a magnetic field that also suppresses gas cell electrons and then recovered on a ground-potential surface. Under optimum conditions, a recovery efficiency (the ratio of the net recovered current to the available full-energy ion current) of 80% +- 20% has been obtained. Magnetic suppression of the beam plasma electrons was rather easily achieved; however, handling the fractional-energy ions originating from molecular species (H 2 + and H 3 + ) proved to be extremely important to recovery efficiency

An investigation into the effects of residual water on the glass transition temperature of polylactide microspheres using modulated temperature DSC.

Science.gov (United States)

Passerini, N; Craig, D Q

2001-05-18

The objective of the study was to ascertain residual water levels in polylactide and polylactide-co-glycolide microspheres prepared using the solvent evaporation technique and to investigate the effects of that water on the glass transitional behaviour of the microspheres. Microspheres were prepared from polylactic acid (PLA) and polylactide-co-glycolide (PLGA) 50:50 and 75:25 using a standard solvent evaporation technique. The glass transition was measured as a function of drying conditions using modulated temperature DSC. The microspheres were found to contain very low levels of dichloromethane, while residual water levels of up to circa 3% w/w were noted after freeze or oven drying, these levels being higher for microspheres containing higher glycolic acid levels. The residual water was found to lower the T(g) following the Gordon-Taylor relationship. The data indicate that the microparticles may retain significant water levels following standard preparation and drying protocols and that this drying may markedly lower the T(g) of the spheres.

Estimation of polycyclic aromatic hydrocarbon concentrations in the water column based on tissue residues in mussels and salmon: An equilibrium partitioning approach

International Nuclear Information System (INIS)

Neff, J.M.; Burns, W.A.

1996-01-01

Equilibrium partitioning was used to estimate concentrations of dissolved polycyclic aromatic hydrocarbons (PAHs) in the water column from PAH residues in tissues of mussels and juvenile pink salmon collected from coastal marine waters affected by the Exxon Valdez oil spill. Estimated concentrations were within factors of 2 to 5 for fish and 5 to 10 for mussels of average total dissolved and particulate PAHs measured in concurrent water samples. Temporal trends of estimated and measured water-column PAH concentrations were comparable. Water-column PAH concentrations estimated from residues in tissues of mussels (Mytilus trossulus) were higher than estimates based on residues in tissues of juvenile pink salmon (Oncorhynchus gorbuscha). Possible reasons for this difference include seasonal variations in mussel lipid content, differences in PAH uptake and depuration rates between fish and mussels, differences in how fish and mussels interact with particulate oil, and possible short exposure times for juvenile pink salmon. All of these factors may play a role. In any event, estimates of dissolved PAHs in the water column, based on PAH residues in either fish or mussel tissue, confirm that PAH concentrations generally did not exceed water quality standards for protection of marine life

Effect of water treatment residuals on soil phosphorus, copper and aluminium availability and toxicity

Energy Technology Data Exchange (ETDEWEB)

Lombi, E., E-mail: enzo.lombi@unisa.edu.a [CSIRO Land and Water, Centre for Environmental Contaminant Research, PMB 2, Glen Osmond, SA 5064 (Australia); Centre for Environmental Risk Assessment and Remediation, University of South Australia, Building X, Mawson Lakes Campus, Mawson Lakes, SA 5095 (Australia); CRC CARE, PO Box 486, Salisbury, SA 5106 (Australia); Stevens, D.P. [CSIRO Land and Water, Centre for Environmental Contaminant Research, PMB 2, Glen Osmond, SA 5064 (Australia); Arris Pty Ltd, PO Box 5143, Burnley, Victoria 3121 (Australia); McLaughlin, M.J. [CSIRO Land and Water, Centre for Environmental Contaminant Research, PMB 2, Glen Osmond, SA 5064 (Australia); Soil and Land Systems, University of Adelaide, PMB 1, Glen Osmond, SA 5064 (Australia)

2010-06-15

Water treatment residuals (WTRs) are produced by the treatment of potable water with coagulating agents. Beneficial recycling in agriculture is hampered by the fact that WTRs contain potentially toxic contaminants (e.g. copper and aluminium) and they bind phosphorus strongly. These issues were investigated using a plant bioassay (Lactuca sativa), chemical extractions and an isotopic dilution technique. Two WTRs were applied to an acidic and a neutral pH soil at six rates. Reductions in plant growth in amended soils were due to WTR-induced P deficiency, rather than Al or Cu toxicity. The release of potentially toxic Al from WTRs was found to be mitigated by their alkaline nature and pH buffering capacity. However, acidification of WTRs was shown to release more soluble Al than soil naturally high in Al. Copper availability was relatively low in all treatments. However, the lability of WTR-Cu increased when the WTR was applied to the soil. - The effect of water treatment residue application to soil was investigated in relation to phosphorus availability, and copper and aluminium phytotoxicity.

Effect of water treatment residuals on soil phosphorus, copper and aluminium availability and toxicity

International Nuclear Information System (INIS)

Lombi, E.; Stevens, D.P.; McLaughlin, M.J.

2010-01-01

Water treatment residuals (WTRs) are produced by the treatment of potable water with coagulating agents. Beneficial recycling in agriculture is hampered by the fact that WTRs contain potentially toxic contaminants (e.g. copper and aluminium) and they bind phosphorus strongly. These issues were investigated using a plant bioassay (Lactuca sativa), chemical extractions and an isotopic dilution technique. Two WTRs were applied to an acidic and a neutral pH soil at six rates. Reductions in plant growth in amended soils were due to WTR-induced P deficiency, rather than Al or Cu toxicity. The release of potentially toxic Al from WTRs was found to be mitigated by their alkaline nature and pH buffering capacity. However, acidification of WTRs was shown to release more soluble Al than soil naturally high in Al. Copper availability was relatively low in all treatments. However, the lability of WTR-Cu increased when the WTR was applied to the soil. - The effect of water treatment residue application to soil was investigated in relation to phosphorus availability, and copper and aluminium phytotoxicity.

Mixing regime of the residual water basins of the Aral Sea

Science.gov (United States)

Izhitskiy, Alexander; Zavialov, Peter; Kirillin, Georgiy

2017-04-01

The Aral Sea, a terminal salt lake in western Central Asia situated at the border between Uzbekistan and Kazakhstan, was ranked as the fourth largest inland water body in the mid-20th century. However, in the early 1960s, the lake's volume started to decrease rapidly due to severe changes in the Aral's water balance. Thus, the present-day Aral Sea can be considered as a system of separate water bodies with a common origin but very different physical, chemical and biological features. Our previous studies showed that the Large Aral Sea and Lake Tshchebas transformed into hyperhaline water bodies, while the Small Aral Sea was a brackish basin with rather similar to the pre-desiccation environment. On the other hand, the Small Aral Sea and Lake Tshchebas exhibited a mixed vertical structure, whereas the Western Large Aral Sea (especially the Chernyshev Bay) was strongly stratified. The presented study is focused on the seasonal mixing regimes of the residual basins. Isolation of deep waters from the atmosphere together with low rates of photosynthesis produce deep anoxia observed in the Chernyshev Bay and in the Large Aral. The high amount of organic matter provides a rich source of nutrients for anoxic microorganisms favoring methanogenesis in the bottom layer of the basins. In the Small Aral, the water column remains well-oxygenated down to the bottom throughout most of the year and development of anoxia is unlikely. The mixing regimes of the recently formed residual lakes of the former Aral Sea will provide manifold effect on the ongoing development of the aquatic system in the following decades. The study is based on a field data collected during two surveys of Shirshov Institute of Oceanology to the Aral Sea, which took place in October, 2015 and June, 2016. In situ measurements including CTD profiling and water sampling were carried out in the northern extremity of the western Large Aral (the Chernyshev Bay), in Lake Tshchebas, and in the Small Aral Sea

Detection of pesticides residues in water samples from organic and conventional paddy fields of Ledang, Johor, Malaysia

Science.gov (United States)

Abdullah, Md Pauzi; Othman, Mohamed Rozali; Ishak, Anizan; Nabhan, Khitam Jaber

2016-11-01

Pesticides have been used extensively by the farmers in Malaysia during the last few decades. Sixteen water samples, collected from paddy fields both organic and conventional, from Ledang, Johor, were analyzed to determine the occurrence and distribution of organochlorine (OCPs) and organophosphorus (OPPs) pesticide residues. GC-ECD instrument was used to identify and determine the concentrations of these pesticide residues. Pesticide residues were detected in conventional fields in the range about 0.036-0.508 µg/L higher than detected in organic fields about 0.015-0.428 µg/L. However the level of concentration of pesticide residues in water sample from both paddy fields are in the exceed limit for human consumption, according to European Economic Commission (EEC) (Directive 98/83/EC) at 0.1 µg/L for any pesticide or 0.5 µg/L for total pesticides. The results that the organic plot is still contaminated with pesticides although pesticides were not use at all in plot possibly from historical used as well as from airborne contamination.

Compostagem da fração sólida da água residuária de suinocultura Solid fraction composting of residual water from pig farms

Directory of Open Access Journals (Sweden)

Marco A. P. Orrico Júnior

2009-09-01

Full Text Available Avaliar o desenvolvimento do processo de compostagem utilizando como substrato à fração sólida da água residuária de suinocultura foi o objetivo deste trabalho. Para a obtenção da fração sólida, a água residuária de suinocultura foi submetida ao peneiramento, utilizando-se de peneira com malha de 1 milímetro. Após separação, a fração sólida foi utilizada para a confecção de três leiras de compostagem, em pátio com piso de concreto e cobertura plástica. Durante a compostagem da fração sólida da água residuária de suinocultura, foram avaliados: temperatura, reduções de sólidos totais (ST, sólidos voláteis (SV, demanda química de oxigênio (DQO, carbono orgânico, matéria orgânica compostável (MOC, matéria orgânica resistente à compostagem (MORC, números mais prováveis (NMPs de coliformes totais e coliformes termotolerantes, além do volume e dos teores de nutrientes no composto. A compostagem mostrou-se eficiente no tratamento da fração sólida da água residuária de suinocultura devido à elevada minimização do poder poluente dos dejetos, observando-se reduções de 71,24% nos teores de ST, 64,55% no volume, 56,89% no teor de DQO e 56,89% na MOC. Foram verificadas reduções de 100% nos NMPs de coliformes totais e termotolerantes, o que possibilita seu uso como adubo orgânico.This work aimed to evaluate the development of the composting process by using the solid fraction of residual water from a pig farm. To obtain the solid fraction, the residual water was sewed in a 1mm screen sew. After separation, the solid fraction was used to form three composting piles, on a patio with concrete floor and plastic cover. During composting the solid fraction of residual water from pig farms was monitored: temperature, total solids reduction (TS, volatile solids (VS chemical demand for oxygen (CDO, organic carbon, compostable organic matter (COM, organic matter resistant to composting (OMRC, most probable

Suppression of dust explosions and ignition spots in biomass-fired power plants

Energy Technology Data Exchange (ETDEWEB)

Wilen, C.; Rautalin, A.

1995-12-31

Dust explosion characteristics of forest residue dust both at normal pressure and at elevated initial pressure have been determined in previous studies. These indices give a good base for evaluating the usability of suppression systems to obtain a sufficient level of peritoneal safety in biomass fuel handling equipment. The objectives of this project were to evaluate the usability of suppression systems and to demonstrate dust explosion suppression at elevated initial pressure. Suppression tests at 1 - 20 bar pressure will be carried out in co-operation with CTDD of British Coal, Kiddy Fire Protection and Health and Safety Executive. The tests with coal and biomass dust are scheduled to be started in March 1996 in Great Britain. In the second task of the project, self-ignition properties of forest residue dust and straw dust have been measured in a flow-through system simulating slow drying of the fuel

Suppression of dust explosions and ignition spots in biomass-fired power plants

Energy Technology Data Exchange (ETDEWEB)

Wilen, C; Rautalin, A

1996-12-31

Dust explosion characteristics of forest residue dust both at normal pressure and at elevated initial pressure have been determined in previous studies. These indices give a good base for evaluating the usability of suppression systems to obtain a sufficient level of peritoneal safety in biomass fuel handling equipment. The objectives of this project were to evaluate the usability of suppression systems and to demonstrate dust explosion suppression at elevated initial pressure. Suppression tests at 1 - 20 bar pressure will be carried out in co-operation with CTDD of British Coal, Kiddy Fire Protection and Health and Safety Executive. The tests with coal and biomass dust are scheduled to be started in March 1996 in Great Britain. In the second task of the project, self-ignition properties of forest residue dust and straw dust have been measured in a flow-through system simulating slow drying of the fuel

Suppression of dust explosions and ignition spots in biomass- fired power plants

Energy Technology Data Exchange (ETDEWEB)

Wilen, C; Rautalin, A [VTT Energy, Espoo (Finland)

1997-12-01

Dust explosion characteristics of forest residue dust both at normal pressure and at elevated initial pressure have been determined in previous studies. These indices give a good base for evaluating the usability of suppression systems to obtain a sufficient level of operational safety in biomass fuel handling equipment. The objectives of this project were to evaluate the usability of suppression systems and to demonstrate dust explosion suppression at elevated initial pressure. Suppression tests at 1 - 20 bar pressure will be carried out in co-operation with CTDD of British Coal, Kiddy Fire Protection and Health and Safety Executive. The tests with coal and biomass dust are scheduled to be started in March 1996 in Great Britain. In the second task of the project, self-ignition properties of forest residue dust and straw dust have been measured in a flow-through system simulating slow drying of the fuel

Competition for water vapour results in suppression of ice formation in mixed-phase clouds

Directory of Open Access Journals (Sweden)

E. L. Simpson

2018-05-01

Full Text Available The formation of ice in clouds can initiate precipitation and influence a cloud's reflectivity and lifetime, affecting climate to a highly uncertain degree. Nucleation of ice at elevated temperatures requires an ice nucleating particle (INP, which results in so-called heterogeneous freezing. Previously reported measurements for the ability of a particle to nucleate ice have been made in the absence of other aerosol which will act as cloud condensation nuclei (CCN and are ubiquitous in the atmosphere. Here we show that CCN can outcompete INPs for available water vapour thus suppressing ice formation, which has the potential to significantly affect the Earth's radiation budget. The magnitude of this suppression is shown to be dependent on the mass of condensed water required for freezing. Here we show that ice formation in a state-of-the-art cloud parcel model is strongly dependent on the criteria for heterogeneous freezing selected from those previously hypothesised. We have developed an alternative criteria which agrees well with observations from cloud chamber experiments. This study demonstrates the dominant role that competition for water vapour can play in ice formation, highlighting both a need for clarity in the requirements for heterogeneous freezing and for measurements under atmospherically appropriate conditions.

Competition for water vapour results in suppression of ice formation in mixed-phase clouds

Science.gov (United States)

Simpson, Emma L.; Connolly, Paul J.; McFiggans, Gordon

2018-05-01

The formation of ice in clouds can initiate precipitation and influence a cloud's reflectivity and lifetime, affecting climate to a highly uncertain degree. Nucleation of ice at elevated temperatures requires an ice nucleating particle (INP), which results in so-called heterogeneous freezing. Previously reported measurements for the ability of a particle to nucleate ice have been made in the absence of other aerosol which will act as cloud condensation nuclei (CCN) and are ubiquitous in the atmosphere. Here we show that CCN can outcompete INPs for available water vapour thus suppressing ice formation, which has the potential to significantly affect the Earth's radiation budget. The magnitude of this suppression is shown to be dependent on the mass of condensed water required for freezing. Here we show that ice formation in a state-of-the-art cloud parcel model is strongly dependent on the criteria for heterogeneous freezing selected from those previously hypothesised. We have developed an alternative criteria which agrees well with observations from cloud chamber experiments. This study demonstrates the dominant role that competition for water vapour can play in ice formation, highlighting both a need for clarity in the requirements for heterogeneous freezing and for measurements under atmospherically appropriate conditions.

Residual fluxes of salt and water in the Azhikode estuary, west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Pylee, A.; Varma, P.U.; Revichandran, C.

hours at all stations and the data were analysed to provide estimates of the residual fluxes of water and salt. The interpolated data for the non-dimensional depth was used for computation of depth, tide and cross sectional averages. A net seaward flow...

Pre-concentration of pesticide residues in environmental water samples using Silica nanoparticles and identification of residues By GC-MS method

OpenAIRE

Tentu. Nageswara Rao; A. Muralidhar Reddy; SNVS. Murthy; Prathipati Revathi; K. Suneel Kumar

2016-01-01

The silica nanoparticles prepared by stober’s mechanism by reaction of tetraethylorthosilicate (TEOS) with ammonia was tested for their adsorption capacity in the pre-concentration of residues of pesticides in water. The synthesized nanoparticles were characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and X-Ray Diffraction (XRD). The size of the silica nanoparticles were 50 to 250 nm. The solid phase extraction (SPE) cartridges were prepared by filling...

Direct gas-solid carbonation of serpentinite residues in the absence and presence of water vapor: a feasibility study for carbon dioxide sequestration.

Science.gov (United States)

Veetil, Sanoopkumar Puthiya; Pasquier, Louis-César; Blais, Jean-François; Cecchi, Emmanuelle; Kentish, Sandra; Mercier, Guy

2015-09-01

Mineral carbonation of serpentinite mining residue offers an environmentally secure and permanent storage of carbon dioxide. The strategy of using readily available mining residue for the direct treatment of flue gas could improve the energy demand and economics of CO2 sequestration by avoiding the mineral extraction and separate CO2 capture steps. The present is a laboratory scale study to assess the possibility of CO2 fixation in serpentinite mining residues via direct gas-solid reaction. The degree of carbonation is measured both in the absence and presence of water vapor in a batch reactor. The gas used is a simulated gas mixture reproducing an average cement flue gas CO2 composition of 18 vol.% CO2. The reaction parameters considered are temperature, total gas pressure, time, and concentration of water vapor. In the absence of water vapor, the gas-solid carbonation of serpentinite mining residues is negligible, but the residues removed CO2 from the feed gas possibly due to reversible adsorption. The presence of small amount of water vapor enhances the gas-solid carbonation, but the measured rates are too low for practical application. The maximum CO2 fixation obtained is 0.07 g CO2 when reacting 1 g of residue at 200 °C and 25 barg (pCO2 ≈ 4.7) in a gas mixture containing 18 vol.% CO2 and 10 vol.% water vapor in 1 h. The fixation is likely surface limited and restricted due to poor gas-solid interaction. It was identified that both the relative humidity and carbon dioxide-water vapor ratio have a role in CO2 fixation regardless of the percentage of water vapor.

In-situ observation of dislocation and analysis of residual stresses by FEM/DDM modeling in water cavitation peening of pure titanium

International Nuclear Information System (INIS)

Ju, D Y; Han, B

2015-01-01

In this paper, in order to approach this problem, specimens of pure titanium were treated with WCP, and the subsequent changes in microstructure, residual stress, and surface morphologies were investigated as a function of WCP duration. The influence of water cavitation peening (WCP) treatment on the microstructure of pure titanium was investigated. A novel combined finite element and dislocation density method (FEM/DDM), proposed for predicting macro and micro residual stresses induced on the material subsurface treated with water cavitation peening, is also presented. A bilinear elastic-plastic finite element method was conducted to predict macro-residual stresses and a dislocation density method was conducted to predict micro-residual stresses. These approaches made possible the prediction of the magnitude and depth of residual stress fields in pure titanium. The effect of applied impact pressures on the residual stresses was also presented. The results of the FEM/DDM modeling were in good agreement with those of the experimental measurements. (paper)

Pressure suppression device

International Nuclear Information System (INIS)

Mizumachi, Wataru; Fukuda, Akira; Kitaguchi, Hidemi; Shimizu, Toshiaki.

1976-01-01

Object: To relieve and absorb impact wave vibrations caused by steam and non-condensed gases releasing into the pressure suppression chamber at the time of an accident. Structure: The reactor container is filled with inert gases. A safety valve attached main steam pipe is provided to permit the excessive steam to escape, the valve being communicated with the pressure suppression chamber through an exhaust pipe. In the pressure suppression chamber, a doughnut-like cylindrical outer wall is filled at its bottom with pool water to condense the high temperature vapor released through the exhaust pipe. A head portion of a vent tube which leads the exhaust pipe is positioned at the top, and a down comer and an exhaust vent tube are locked by means of steady rests. At the bottom is mounted a pressure adsorber device which adsorbs a pressure from the pool water. (Kamimura, M.)

Instrumenting a pressure suppression experiment for a Mark I boiling water reactor: another measurements engineering challenge

International Nuclear Information System (INIS)

Shay, W.M.; Brough, W.G.; Miller, T.B.

1978-01-01

A 1 / 5 -scale test facility of a pressure-suppression system from a Mark I boiling water reactor was instrumented with seven types of transducers to obtain high-accuracy, dynamic loading data during a hypothetical loss-of-coolant accident. A total of 27 air tests have been completed with an average of 175 transducers recorded for each test. An end-to-end calibration of the total measurement system was run to establish accuracy of the data. The instrumentation verified the analysis of the dynamic loading of the pressure-suppression system

Sublimation and transport of water from the north residual polar cap on Mars

Science.gov (United States)

Haberle, Robert M.; Jakosky, Bruce M.

1990-01-01

The possible role of the north residual cap in the current Martian water cycle was examined using models to assess the ability of the cap to supply water to the atmosphere and the ability of the atmospheric circulation to transport it out of the polar regions to low northern latitudes. Results indicate that rather extreme circumstances would be required for the cap to provide all of the observed increase in atmospheric water, such as a combination of high surface winds, low cap emissivities, or substantial evaporation from dark material. But even if these conditions could be met, the high-latitude circulation is too localized in scale to move much water vapor out of the polar environment. Both the present calculations and the data from the Viking's Mars Atmospheric Water Detection Experiment show that about two thirds of the water appearing in the Martian northern hemisphere during summer must be supplied by other sources. It is suggested that the additional source is water desorbing from the nonpolar regolith.

A procedure for evaluating residual life of major components in light water reactors

International Nuclear Information System (INIS)

Uchida, S.; Fujimori, H.; Ibe, E.; Kuniya, J.; Hayashi, M.; Fuse, M.; Yamauchi, K.

1995-01-01

A computer program for evaluating residual life of major components in boiling water reactors is proposed. It divides the stress corrosion cracking process into two stages; a probabilistic crack generation stage and a deterministic crack propagation one. The minimum period of the crack generation stage is evaluated assuming an exponential distribution of the stage. The crack propagation rate is calculated by the slip-dissolution/film-rupture model. The neutron flux and fluence dependence of the neutron radiation effects on material properties was evaluated by using theoretical models of radiation damage. The computer program works on an engineering work station. Evaluated results are displayed as a map of the residual life, or as graphs of crack length evolution

Using of abrasive water jet for measurement of residual stress in railway wheels

Czech Academy of Sciences Publication Activity Database

Hlaváček, Petr; Brumek, J.; Horsák, L.

2012-01-01

Roč. 2, č. 19 (2012), s. 387-390 ISSN 1330-3651 R&D Projects: GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : abrasive water jet * railway wheel * residual stress Subject RIV: JQ - Machines ; Tools Impact factor: 0.601, year: 2012 http://hrcak.srce.hr/index.php?show=clanak&id_clanak_jezik=124848

Volume of baseline data on radioactivity in drinking water, ground water, waste water, sewage sludge, residues and wastes of the annual report 1988 'Environmental radioactivity and radiation exposure'

International Nuclear Information System (INIS)

Abelmann, S.; Buenger, T.; Fusban, H.U.; Ruehle, H.; Viertel, H.; Gans, I.

1991-01-01

This WaBoLu volume is a shortened version of the annual report by the Federal Ministry of the Environment, Nature Protection and Reactor Safety 'Environmental radioactivity and radiation exposure' and gives an overview of the data on radioactivity in drinking water, ground water, waste water, sewage sludge, residues and wastes, compiled for the area of the Federal Republic of Germany in 1988 by the Institute of Water, Soil and Air Hygiene (WaBoLu) of the Federal Health Office. (BBR) With 22 figs., 15 tabs [de

Role of residual water hydrogen bonding in sugar/water/biomolecule systems: a possible explanation for trehalose peculiarity

Energy Technology Data Exchange (ETDEWEB)

Cordone, L; Cottone, G; Giuffrida, S [Dipartimento di Scienze Fisiche ed Astronomiche, Universita di Palermo and CNISM (Italy)

2007-05-23

We report on the set of experimental and simulative evidences which enabled us to suggest how biological structures embedded in a non-liquid water-saccharide solvent are anchored to the surrounding matrix via a hydrogen bond network. Such a network, whose rigidity increases by decreasing the sample water content, couples the degrees of freedom of the biostructure to those of the matrix and gives place to protein-saccharide-water structures (protein-solvent conformational substates). In particular, the whole set of data evidences that, while the protein-sugar interaction is well described in terms of a water entrapment hypothesis, the water replacement hypothesis better describes the sugar-membrane interaction; furthermore, it gives a hint towards the understanding of the origin of the trehalose peculiarity since the biomolecule-matrix coupling, specific to each particular sugar, always results in being the tightest for trehalose. In line with the heterogeneous dynamics in supercooled fluids and in carbohydrate glasses of different residual water contents, recent results confirm, at the single molecule level, the existence of protein-solvent conformational substates, spatially heterogeneous and interconverting, whose rigidity increases by lowering the sample hydration.

Position of residues in transmembrane peptides with respect to the lipid bilayer: A combined lipid NOEs and water chemical exchange approach in phospholipid bicelles

International Nuclear Information System (INIS)

Glover, Kerney Jebrell; Whiles, Jennifer A.; Vold, Regitze R.; Melacini, Giuseppe

2002-01-01

The model transmembrane peptide P16 was incorporated into small unaligned phospholipid bicelles, which provide a 'native-like' lipid bilayer compatible with high-resolution solution NMR techniques. Using amide-water chemical exchange and amide-lipid cross-relaxation measurements, the interactions between P16 and bicelles were investigated. Distinctive intermolecular NOE patterns observed in band-selective 2D-NOESY spectra of bicellar solutions with several lipid deuteration schemes indicated that P16 is preferentially interacting with the 'bilayered' region of the bicelle rather than with the rim. Furthermore, when amide-lipid NOEs were combined with amide-water chemical exchange cross-peaks of selectively 15 N-labeled P16 peptides, valuable information was obtained about the position of selected residues relative to the membrane-water interface. Specifically, three main classes were identified. Class I residues lie outside the bilayer and show amide-water exchange cross-peaks but no amide-lipid NOEs. Class II residues reside in the bilayer-water interface and show both amide-water exchange cross-peaks and amide-lipid NOEs. Class III residues are embedded within the hydrophobic core of the membrane and show no amide-water exchange cross-peaks but strong amide-lipid NOEs

Nutrient removal capacity of wood residues for the Agro-environmental safety of ground and surface waters

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Paulo A. Dumont

2014-07-01

Full Text Available The aim of this study was to determine the effectiveness of wood residues in the removal of nutrients (ammonium-N; NH4-N from nutrient-rich (NH4-N waters. The water holding capacity of the wood materials was also determined. Carried out at Rothamsted Research, North Wyke, UK, this controlled laboratory experiment tested two wood residues; in length, one being 1-2cm and the other from 150 µm (microns to 9.5mm. Although a wide range of studies have shown the effectiveness and performance of various absorbent materials as animal beddings, such as straw (cereal straw, woodchip (sawdust, bark or wood shavings, bracken and rushes, only few have focused on the NH4-N sorption/desorption capacity. The depuration capacity of wood residues from nutrient-rich effluents such as those from cattle bedded on woodchip or straw will be controlled by processes such as sorption (adsorption-absorption and desorption of nutrients. Studies have reported the nitrogen removal capacity of woodchip materials and biochar from woodchip as well as removal of NH4+-N from domestic and municipal wastewater, farm dirty water, landfill and industry effluents. These studies have observed that the mechanism of removal of nitrogen is by either increasing NO3--N removal form leachate by enhancing N2O losses via denitrification (biochar as carbon source for denitrifiers or by decreasing NH4+-N in leachate through adsorption to negatively charged sites. Results showed that although the cation exchange capacity (CEC and surface area (SA are both fundamental properties of adsorbent materials, no correlation was found with CEC and adsorption or desorption. Nor did changes in pH appear to be sufficiently important to cause changes in CEC. For this reason, osmotic pressure appeared to be a more predominant parameter controlling processes of adsorption and desorption of NH4+-N in both wood residues. Thus, wood residues high in NH4+-N should be avoided, as they could have an opposite effect

Neonicotinoid insecticide residues in surface water and soil associated with commercial maize (corn fields in southwestern Ontario.

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Arthur Schaafsma

Full Text Available Neonicotinoid insecticides have come under scrutiny for their potential unintended effects on non-target organisms, particularly pollinators in agro-ecosystems. As part of a larger study of neonicotinoid residues associated with maize (corn production, 76 water samples within or around the perimeter of 18 commercial maize fields and neighbouring apiaries were collected in 5 maize-producing counties of southwestern Ontario. Residues of clothianidin (mean = 2.28, max. = 43.60 ng/mL and thiamethoxam (mean = 1.12, max. = 16.50 ng/mL were detected in 100 and 98.7% of the water samples tested, respectively. The concentration of total neonicotinoid residues in water within maize fields increased six-fold during the first five weeks after planting, and returned to pre-plant levels seven weeks after planting. However, concentrations in water sampled from outside the fields were similar throughout the sampling period. Soil samples from the top 5 cm of the soil profile were also collected in these fields before and immediately following planting. The mean total neonicotinoid residue was 4.02 (range 0.07 to 20.30 ng/g, for samples taken before planting, and 9.94 (range 0.53 to 38.98 ng/g, for those taken immediately after planting. Two soil samples collected from within an conservation area contained detectable (0.03 and 0.11 ng/g concentrations of clothianidin. Of three drifted snow samples taken, the drift stratum containing the most wind-scoured soil had 0.16 and 0.20 ng/mL mainly clothianidin in the melted snow. The concentration was at the limit of detection (0.02 ng/mL taken across the entire vertical profile. With the exception of one sample, water samples tested had concentrations below those reported to have acute, chronic or sublethal effects to honey bees. Our results suggest that neonicotinoids may move off-target by wind erosion of contaminated soil. These results are informative to risk assessment models for other non-target species in maize

Neonicotinoid Insecticide Residues in Surface Water and Soil Associated with Commercial Maize (Corn) Fields in Southwestern Ontario

Science.gov (United States)

Schaafsma, Arthur; Limay-Rios, Victor; Baute, Tracey; Smith, Jocelyn; Xue, Yingen

2015-01-01

Neonicotinoid insecticides have come under scrutiny for their potential unintended effects on non-target organisms, particularly pollinators in agro-ecosystems. As part of a larger study of neonicotinoid residues associated with maize (corn) production, 76 water samples within or around the perimeter of 18 commercial maize fields and neighbouring apiaries were collected in 5 maize-producing counties of southwestern Ontario. Residues of clothianidin (mean = 2.28, max. = 43.60 ng/mL) and thiamethoxam (mean = 1.12, max. = 16.50 ng/mL) were detected in 100 and 98.7% of the water samples tested, respectively. The concentration of total neonicotinoid residues in water within maize fields increased six-fold during the first five weeks after planting, and returned to pre-plant levels seven weeks after planting. However, concentrations in water sampled from outside the fields were similar throughout the sampling period. Soil samples from the top 5 cm of the soil profile were also collected in these fields before and immediately following planting. The mean total neonicotinoid residue was 4.02 (range 0.07 to 20.30) ng/g, for samples taken before planting, and 9.94 (range 0.53 to 38.98) ng/g, for those taken immediately after planting. Two soil samples collected from within an conservation area contained detectable (0.03 and 0.11 ng/g) concentrations of clothianidin. Of three drifted snow samples taken, the drift stratum containing the most wind-scoured soil had 0.16 and 0.20 ng/mL mainly clothianidin in the melted snow. The concentration was at the limit of detection (0.02 ng/mL) taken across the entire vertical profile. With the exception of one sample, water samples tested had concentrations below those reported to have acute, chronic or sublethal effects to honey bees. Our results suggest that neonicotinoids may move off-target by wind erosion of contaminated soil. These results are informative to risk assessment models for other non-target species in maize agro

Isolation of a bacteria of the Bacillus genus as indicator in the disinfection of residual waters by means of the ionizing radiation (e- , γ)

International Nuclear Information System (INIS)

Mata J, M.

2003-01-01

The pollutants of the water can be chemical, physical and biological. Among those biological we find to the microorganisms: bacterias, virus and protozoa. These cause important infections in many countries, mainly of Latin America. With the advance of the technology and the quick demographic growth, the biological pollution of the water has already become an important topic since it would damage the public health and it causes that their disinfection has greater attention. In the treatment of residual waters three basic treatments exist the one primary, secondary and tertiary; in this last we find the disinfection, which can be taken to end by chemical and physical methods. For this work of investigation it was used the ionizing radiation, because it is an innovative technology that it eliminates microorganisms in residual waters. The investigation consisted on treating, samples of residual water after the biological treatment of the plant RECICLAGUA with ionizing radiation (electrons and gammas), for the case of electrons it was used the dose of 0.5 kGy and for gamma the dose, of 5 kGy, later the survivor bacteria was isolated to these doses in both cases and they were carried out the tests of identification. In accordance with the obtained results can say that it is about a B. subtilis. The isolated B.subtilis was presented as a pollutant of the flora of the residual water, having a greater survival to the dose of 0.5 and 5 kGy with electrons and gammas, respectively that other present polluting microorganisms in the samples of residual water. For it fits signalize that this microorganism shows characteristics as it easy isolation and identification, the presence with pathogen microorganisms and a greater survival when being irradiated, therefore it can use as indicator in the disinfection of residual waters through ionizing radiation (electrons and gammas). (Author)

Electro-suppression of water nano-droplets' solidification in no man's land: Electromagnetic fields' entropic trapping of supercooled water

Science.gov (United States)

Nandi, Prithwish K.; Burnham, Christian J.; English, Niall J.

2018-01-01

Understanding water solidification, especially in "No Man's Land" (NML) (150 K < T < 235 K) is crucially important (e.g., upper-troposphere cloud processes) and challenging. A rather neglected aspect of tropospheric ice-crystallite formation is inevitably present electromagnetic fields' role. Here, we employ non-equilibrium molecular dynamics of aggressively quenched supercooled water nano-droplets in the gas phase under NML conditions, in externally applied electromagnetic (e/m) fields, elucidating significant differences between effects of static and oscillating fields: although static fields induce "electro-freezing," e/m fields exhibit the contrary - solidification inhibition. This anti-freeze action extends not only to crystal-ice formation but also restricts amorphisation, i.e., suppression of low-density amorphous ice which forms otherwise in zero-field NML environments. E/m-field applications maintain water in the deeply supercooled state in an "entropic trap," which is ripe for industrial impacts in cryo-freezing, etc.

Cooling device for reactor suppression pool

International Nuclear Information System (INIS)

Togasaki, Susumu; Kato, Kiyoshi.

1994-01-01

In a cooling device of a reactor suppression pool, when a temperature of pool water is abnormally increased and a heat absorbing portion is heated by, for example, occurrence of an accident, coolants are sent to the outside of the reactor container to actuates a thermally operating portion by the heat energy of coolants and drive heat exchanging fluids of a secondary cooling system. If the heat exchanging fluids are sent to a cooling portion, the coolants are cooled and returned to the heat absorbing portion of the suppression pool water. If the heat absorbing portion is heat pipes, the coolants are evaporated by heat absorbed from the suppression pool water, steams are sent to the thermally operating portion, then coolants are liquefied and caused to return to the heat absorbing portion. If the thermal operation portion is a gas turbine, the gas turbine is operated by the coolants, and it is converted to a rotational force to drive heat exchanging fluids by pumps. By constituting the cooling portion with a condensator, the coolants are condensed and liquefied and returned to the heat absorbing portion of the suppression pool water. (N.H.)

Synthesis, characterization and fluorescent properties of water-soluble glycopolymer bearing curcumin pendant residues.

Science.gov (United States)

Zhang, Haisong; Yu, Meng; Zhang, Hailei; Bai, Libin; Wu, Yonggang; Wang, Sujuan; Ba, Xinwu

2016-08-01

Curcumin is a potential natural anticancer drug with low oral bioavailability because of poor water solubility. The aqueous solubility of curcumin is enhanced by means of modification with the carbohydrate units. Polymerization of the curcumin-containing monomer with carbohydrate-containing monomer gives the water-soluble glycopolymer bearing curcumin pendant residues. The obtained copolymers (P1 and P2) having desirable water solubility were well-characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), UV-Vis absorption spectroscopy, and photoluminescence spectroscopy. The copolymer P2 with a molar ratio of 1:6 (curcumin/carbohydrate) calculated from the proton NMR results exhibits a similar anticancer activity compared to original curcumin, which may serve as a potential chemotherapeutic agent in the field of anticancer medicine.

Mark I 1/5-scale boiling water reactor pressure suppression experiment facility report

International Nuclear Information System (INIS)

Altes, R.G.; Pitts, J.H.; Ingraham, R.F.; Collins, E.K.; McCauley, E.W.

1977-01-01

An accurate Mark I 1 / 5 -scale, boiling water reactor (BWR), pressure suppression facility was designed and constructed at Lawrence Livermore Laboratory (LLL) in 11 months. Twenty-seven air tests using the facility are described. Cost was minimized by utilizing equipment borrowed from other LLL programs. The total value of borrowed equipment exceeded the program's budget of $2,020,000. Substantial flexibility in the facility was used to permit independent variation in the drywell pressure-time history, initial pressure in the drywell and toroidal wetwells, initial toroidal wetwell water level and downcomer length, vent line flow resistance, and vent line flow asymmetry. The two- and three-dimensional sectors of the toroidal wetwell provided significant data

Groundwater suppression and surface water diversion structures applied to closed shallow land burial trenches

International Nuclear Information System (INIS)

Davis, E.C.; Stansfield, R.G.; Melroy, L.A.; Huff, D.D.

1984-01-01

Shallow depth to groundwater, surface drainage, and subsurface flow during storm events are major environmental concerns of low-level radioactive waste management operations in humid regions. At two waste disposal sites within the Oak Ridge National Laboratory (ORNL), groups of closed trenches have experienced these problems and have been shown to collect and hold water with seasonal fluctuations ranging from 1 to 2 m. In an attempt to correct these water-related problems, the older of the two sites [Solid Waste Storage Area Four (SWSA 4)] was equipped in September 1975 with asphalt lined drainage-ways designed to prevent infiltration of storm drainage from a 13.8-ha upslope catchment. At the second site (49-Trench area of SWSA 6), the entire 0.44-ha trench area was capped with a bentonite clay cover in 1976. These attempts have not corrected the water problems. In September 1983, engineered drainage projects were initiated at both the disposal sites. The SWSA 4 project was designed to divert surface runoff and shallow subsurface flow which originates upslope of the site away from the disposal area. The second project, a passive French drain constructed in SWSA 6, was aimed strictly at suppressing the site water table, thus preventing its intersection with the bottoms of disposal trenches. Postconstruction monitoring for performance evaluation has shown that the water table in the 49-Trench area has been suppressed to a depth > 4.9 m below the ground surface over 50% of the site as compared to a depth of only 2.1 m for certain parts of the same area observed during seasonally wet months prior to drain construction. The SWSA 4 project evaluation indicates that 56% of the Winter-Spring 1984 runoff was diverted around SWSA 4 via the drainage system

Removal of uranyl ions from residual waters using some algae types

International Nuclear Information System (INIS)

Cecal, Al.; Rudic, V.; Gulea, A.; Palamaru, I.; Humelnicu, D.; Salaru, V.V.; Popa, K.

1997-01-01

This paper deals with a study on the bioaccumulation of uranyl ions resulted from residual effluents, by means of some microbiological collectors: Scenedesmus quadricauda, Anabaena karakumica, Calothrix brevissima, Penicillium sp, as well as the Glucide extract of Porphyridium cruentum, in several experimental conditions. The retaining degree of the bioaccumulated uranyl ions, as well as the leaching degree, in HCl and H 2 O media, of the same ions previously retained on algae, were karakumica >Penicillium sp> Calothrix brevissima. The leaching effect of bioaccumulated uranyl ions is higher in hydrochloric acid then in water. (authors)

Detection of Amide and Aromatic Proton Resonances of Human Brain Metabolites Using Localized Correlated Spectroscopy Combined with Two Different Water Suppression Schemes

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Rajakumar Nagarajan

2010-01-01

Full Text Available The purpose of the study was to demonstrate the J-coupling connectivity network between the amide, aliphatic, and aromatic proton resonances of metabolites in human brain using two-dimensional (2D localized correlated spectroscopy (L-COSY. Two different global water suppression techniques were combined with L-COSY, one before and another after localizing the volume of interest (VOI. Phantom solutions containing several cerebral metabolites at physiological concentrations were evaluated initially for sequence optimization. Nine healthy volunteers were scanned using a 3T whole body MRI scanner. The VOI for 2D L-COSY was placed in the right occipital white/gray matter region. The 2D cross and diagonal peak volumes were measured for several metabolites such as N-acetyl aspartate (NAA, creatine (Cr, free choline (Ch, glutamate/glutamine (Glx, aspartate (Asp, myo-inositol (mI, GABA, glutathione (GSH, phosphocholine (PCh, phosphoethanolamine (PE, tyrosine (Tyr, lactate (Lac, macromolecules (MM and homocarnosine (Car. Using the pre-water suppression technique with L-COSY, the above mentioned metabolites were clearly identifiable and the relative ratios of metabolites were calculated. In addition to detecting multitude of aliphatic resonances in the high field region, we have demonstrated that the amide and aromatic resonances can also be detected using 2D L-COSY by pre water suppression more reliably than the post-water suppression.

Aluminum-Based Water Treatment Residue Reuse for Phosphorus Removal

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Lai Yoke Lee

2015-04-01

Full Text Available Aluminum-based water treatment residue (Al-WTR generated during the drinking water treatment process is a readily available recycled material with high phosphorus (P adsorption capacity. The P adsorption capacity of Al-WTR generated from Singapore’s water treatment plant was evaluated with reference to particle size range, adsorption pH and temperature. Column tests, with WTR amendments in sand with and without compost, were used to simulate the bioretention systems. The adsorption rate decreased with increasing WTR sizes. Highest P adsorption capacity, 15.57 mg PO43−-P/g WTR, was achieved using fine WTR particles (>50% particles at less than 0.30 mm. At pH 4, the contact time required to reduce effluent P concentration to below the detectable range was half compared with pH 7 and 9. The adsorption rate observed at 40 ± 2 °C was 21% higher compared with that at 30 ± 2 °C. Soil mixes amended with 10% WTR and compost were able to maintain consistently high (90% total phosphorus (TP removal efficiency at a TP load up to 6.45 g/m3. In contrast, TP removal efficiencies associated with columns without WTR amendment decreased to less than 45% as the TP load increased beyond 4.5 g/m3. The results showed that WTR application is beneficial for enhanced TP removal in bioretention systems.

Effect of water-washing on the co-removal of chlorine and heavy metals in air pollution control residue from MSW incineration.

Science.gov (United States)

Yang, Zhenzhou; Tian, Sicong; Ji, Ru; Liu, Lili; Wang, Xidong; Zhang, Zuotai

2017-10-01

The present study systemically investigated the effect of a water-washing process on the removal of harmful chlorides, sulfates, and heavy metals in the air pollution control (APC) residue from municipal solid wastes incineration (MSWI), for sake of a better reuse and disposal of this kind of waste. In addition, the kinetic study was conducted to reveal the releasing mechanism of relevant element in the residue. The results show that, over 70wt.% of chlorides and nearly 25wt.% of sulfates in the residue could be removed by water washing. Based on an economical consideration, the optimal operation conditions for water washing of APC residue was at liquid/solid (L/S) ratio of 3mL:1g and extracting time of 5min. As expected, the concentrations of Co, Cr, Fe, Ni, V and Cu in the washing effluent increased with time during the washing process. However, the extracting regime differs among different heavy metals. The concentrations of Ba and Mn increased firstly but declined afterwards, and concentrations of Pb and Zn gradually declined while Cd and As kept constant with the increase of extracting time. It is worth mentioning that the bubbling of CO 2 into the washing effluent is promisingly effective for a further removal of Pb, Cu and Zn. Furthermore, kinetic study of the water washing process reveals that the extracting of heavy metals during water washing follows a second-order model. Copyright © 2017 Elsevier Ltd. All rights reserved.

In vitro residual anti-bacterial activity of difloxacin, sarafloxacin and their photoproducts after photolysis in water

International Nuclear Information System (INIS)

Kusari, Souvik; Prabhakaran, Deivasigamani; Lamshoeft, Marc; Spiteller, Michael

2009-01-01

Fluoroquinolones like difloxacin (DIF) and sarafloxacin (SARA) are adsorbed in soil and enter the aquatic environment wherein they are subjected to photolytic degradation. To evaluate the fate of DIF and SARA, their photolysis was performed in water under stimulated natural sunlight conditions. DIF primarily degrades to SARA. On prolonged photodegradation, seven photoproducts were elucidated by HR-LC-MS/MS, three of which were entirely novel. The residual anti-bacterial activities of DIF, SARA and their photoproducts were studied against a group of pathogenic strains. DIF and SARA revealed potency against both Gram-positive and -negative bacteria. The photoproducts also exhibited varying degrees of efficacies against the tested bacteria. Even without isolating the individual photoproducts, their impact on the aquatic environment could be assessed. Therefore, the present results call for prudence in estimating the fate of these compounds in water and in avoiding emergence of resistance in bacteria caused by the photoproducts of DIF and SARA. - Assessment of the residual anti-bacterial efficacies of difloxacin, sarafloxacin and their photoproducts in water, and estimating their impact on the aquatic environment in inducing resistance to microorganisms.

The Characteristics of Methane Combustion Suppression by Water Mist and Its Engineering Applications

Directory of Open Access Journals (Sweden)

Rongkun Pan

2017-10-01

Full Text Available To safely mine coal, engineers must prevent gas combustion and explosions, as well as seek feasible and reasonable techniques to control for these types of incidents. This paper analyzes the causes and characteristics of methane combustion and explosions. Water mist is proposed to prevent and control methane combustion in an underground confined space. We constructed an experiment platform to investigate the suppression of methane combustion using water mist for different conditions. The experimental results showed that water mist is highly effective for methane flame inhibition. The flame was extinguished with water mist endothermic cooling. However, the annular regions of water vapor around the fire played a vital role in flame extinction. Water from the evaporating mist replaces the oxygen available to the fuel. Additionally, the time required for fuel ignition is prolonged. For these reasons, the water particle action to flame surface is reinforced and the fuel’s reaction with air is delayed. As a result, flame stretching and disturbances occur, which serve to extinguish the flame. Engineering application tests were carried out in the goaf, drill hole and upper-corner to investigate the prevention and control of methane gas combustion, with the results showing a good application effect.

Quantification of heavy metals from residual waste and ashes from the treatment plant of residual water Reciclagua and,effects for the health of those workers which manipulate those residuals

International Nuclear Information System (INIS)

Guerrero D, J.J.

2004-01-01

In this work, the technique of leaching using thermostatted column in series is applied, the X-ray diffraction for the identification of the atomic and molecular structure of the toxic metals that are present in the residual muds of the water treatment plant located in the municipality of Lerma Estado de Mexico, named RECICLAGUA, likewise the technique is used of emission spectrometry for plasma and X-ray fluorescence for the qualitative analysis. Its were take samples of residual mud and of incinerated mud of the treatment plant of residual waters of the industrial corridor Toluca -Lerma RECICLAGUA, located in Lerma Estado de Mexico. For this study there were mixed 100 g of residual mud with a solution to 10% of mineral acid or sodium hydroxide according to the case, to adjust the one pH at 2, 5, 7 and 10, it was added bisulfite, of 0.3-1.5 g of dodecyl sulfate sodium and 3.939 of DTPA (triple V) (Diethylene triamine pentaacetate). To this mud and ashes were extracted the toxic and valuable metals by means of the leaching technique using thermostatted columns placed in series that were designed by the Dr. Jaime Vite Torres; it is necessary to make mention that so much the process as the equipment with those that work it was patented by the same one. With the extraction of these metals benefits are obtained, mainly of economic type, achieving the decrease of the volume of those wastes that have been generated; as well as the so much the use of those residuals, once the metals have been eliminated, as of those liquors where the metals were extracted. It was carried out a quantitative analysis using emission spectrometry by plasma in solids by this way to be able to know the content of the present metals in the sample before and later of leaching them, these results reported a great quantity of elements. Another of the techniques employees was the X-ray diffraction analysis that provides an elementary content of the samples, identifying elements that are present in

NMR studies of stock process water and reaction pathways in hydrothermal carbonization of furfural residue

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Fen Yue

2018-04-01

Full Text Available Hydrothermal carbonization (HTC is a valuable approach to convert furfural residue (FR into carbon material. The prepared biochars are usually characterized comprehensively, while the stock process water still remains to be studied in detail. Herein, a NMR study of the main components in stock process water generated at different HTC reaction conditions was reported. Various qualitative and quantitative NMR techniques (1H and 13C NMR, 1H–1H COSY and 1H13C HSQC etc. especially 1D selective gradient total correlation spectroscopy (TOCSY NMR were strategically applied in the analysis of HTC stock process water. Without separation and purification, it was demonstrated that the main detectable compounds are 5-hydroxymethylfurfural, formic acid, methanol, acetic acid, levulinic acid, glycerol, hydroxyacetone and acetaldehyde in this complicate mixture. Furthermore, the relationship between the concentration of major products and the reaction conditions (180–240 °C at 8 h, and 1–24 h at 240 °C was established. Finally, reasonable reaction pathways for hydrothermal conversion of FR were proposed based on this result and our previously obtained characteristics of biochars. The routine and challenging NMR methods utilized here would be an alternative other than HPLC or GC for biomass conversion research and can be extended to more studies. Keywords: NMR, Hydrothermal carbonization, Furfural residue, Stock process water

Improved crop residue cover estimates by coupling spectral indices for residue and moisture

Science.gov (United States)

Remote sensing assessment of soil residue cover (fR) and tillage intensity will improve our predictions of the impact of agricultural practices and promote sustainable management. Spectral indices for estimating fR are sensitive to soil and residue water content, therefore, the uncertainty of estima...

Radiation degradation of pharmaceutical residues in water. Chloramphenicol

International Nuclear Information System (INIS)

Csay, T.; Racz, G.; Takacs, E.; Wojnarovits, L.

2011-01-01

Complete text of publication follows. Traditional wastewater treatment systems primarily rely upon physical, chemical and biological processes. The conventional techniques cannot efficiently remove badly biodegradable pollutants like pesticides, herbicides and drugs from influents. Leaving 'polluted' water flowing freely out to environment may cause unwanted and sometimes unpredictable effects. Degradation or removal of residual organic contaminations from wastewater is an important task both for science and engineering to preserve environment and drinking water. Ionizing radiation treatment of liquid wastes is one of the so called advanced oxidation processes (AOP) leading to decomposition of pharmaceuticals in aqueous solutions. The radiolysis of chloramphenicol (CPL) a broad spectrum antibiotic was investigated under different conditions. Steady-state gamma radiolysis were used to generate various reactive species ( · H, · OH and e aq - ). Reactions were followed by steady state and time resolved UV-Vis spectrometry. Several degradation products were separated and identified by LC-MS/MS. Mineralization was followed by measuring chemical oxygen demand (COD) and total organic carbon content (TOC). The change in toxicity was followed by Microtox, a luminescent bacteria test. Results indicate that ionizing radiation is very effective in degradation of CPL. After irradiating 0.1 mM CPL solutions with 5.0-7.5 kGy doses, no products could be observed indicating that irradiation resulted in complete mineralization.

Emission of Carbon Dioxide Influenced by Different Water Levels from Soil Incubated Organic Residues

Science.gov (United States)

Hossain, M. B.; Puteh, A. B.

2013-01-01

We studied the influence of different organic residues and water levels on decomposition rate and carbon sequestration in soil. Organic residues (rice straw, rice root, cow dung, and poultry litter) including control were tested under moistened and flooding systems. An experiment was laid out as a complete randomized design at 25°C for 120 days. Higher CO2-C (265.45 mg) emission was observed in moistened condition than in flooding condition from 7 to 120 days. Among the organic residues, poultry litter produced the highest CO2-C emission. Poultry litter with soil mixture increased 121% cumulative CO2-C compared to control. On average, about 38% of added poultry litter C was mineralized to CO2-C. Maximum CO2-C was found in 7 days after incubation and thereafter CO2-C emission was decreased with the increase of time. Control produced the lowest CO2-C (158.23 mg). Poultry litter produced maximum cumulative CO2-C (349.91 mg). Maximum organic carbon was obtained in cow dung which followed by other organic residues. Organic residues along with flooding condition decreased cumulative CO2-C, k value and increased organic C in soil. Maximum k value was found in poultry litter and control. Incorpored rice straw increased organic carbon and decreased k value (0.003 g d−1) in soil. In conclusion, rice straw and poultry litter were suitable for improving soil carbon. PMID:24163626

Hotspots of soil N2O emission enhanced through water absorption by plant residue

Energy Technology Data Exchange (ETDEWEB)

Kravchenko, A.N.; Toosi, E.R.; Guber, A.K.; Ostrom, N.E.; Yu, J.; Azeem, K.; Rivers, M.L.; Robertson , G.P. (UAF Pakistan); (UC); (Hubei); (MSU)

2017-06-05

N2O is a highly potent greenhouse gas and arable soils represent its major anthropogenic source. Field-scale assessments and predictions of soil N2O emission remain uncertain and imprecise due to the episodic and microscale nature of microbial N2O production, most of which occurs within very small discrete soil volumes. Such hotspots of N2O production are often associated with decomposing plant residue. Here we quantify physical and hydrological soil characteristics that lead to strikingly accelerated N2O emissions in plant residue-induced hotspots. Results reveal a mechanism for microscale N2O emissions: water absorption by plant residue that creates unique micro-environmental conditions, markedly different from those of the bulk soil. Moisture levels within plant residue exceeded those of bulk soil by 4–10-fold and led to accelerated N2O production via microbial denitrification. The presence of large (Ø >35 μm) pores was a prerequisite for maximized hotspot N2O production and for subsequent diffusion to the atmosphere. Understanding and modelling hotspot microscale physical and hydrologic characteristics is a promising route to predict N2O emissions and thus to develop effective mitigation strategies and estimate global fluxes in a changing environment.

Technical update on pressure suppression type containments in use in U.S. light water reactor nuclear power plants

International Nuclear Information System (INIS)

1978-07-01

In 1972, Dr. S. H. Hanauer (Technical Advisor to the NRC's Executive Director for Operations) wrote a memorandum that raised several questions on the viability of pressure suppression containment concepts. The concerns raised by Dr. Hanauer have recently become the subject of considerable discussion by several members of the U.S. Congress and public. The report provides a response to these expressed concerns and a status summary for various technical matters that relate to the safety of pressure suppression type containments for light water cooled reactor plants

Residues of lindane and endosulfan in water and fish samples from rivers, farms in Besease, Agogo and Akomadan in the Ashanti region of Ghana

International Nuclear Information System (INIS)

Osafo-Acquaah, S.; Frimpong, E.

1997-01-01

Pesticide residue analyses were performed on water and fish samples from River Oda in Besease, River Aframso in Nobewam near Kumasi, River Atwetwe in Akomadan, and River Kowire at Agogo. Residues of lindane and endosulfan were found in water and fish (Oreochromis niloticus, Tilapia zillii, Barbus trispulis, Heterobranchus sp., Tilapia busumana, Ophiocephalus obscura and Chana obscura) samples. The residues of lindane varied between the years and months in the year but were in the range of 0.3 - 15 ng L -1 (1993-94) and 8.7-32.0 ng L -1 (1995) for the water samples and 0.2-24 ng g -1 (1993-93) and 8.4-120.4 ng g -1 (1995) for the fish samples. Residues of endosulfan in the water and the fish samples were zero in 1993-1994 but, in 1995, were in the range of 6.4-35.2 ng L -1 for the water samples and 5.0-267.5 ng g -1 for the fish samples. In all cases the lindane and ensofulfan concentrations in the water were 10,000-20,000 times lower than known toxic concentration levels and therefore unlikely to cause fish toxicity problems. (author). 11 refs, 4 tabs

Arginine-aromatic interactions and their effects on arginine-induced solubilization of aromatic solutes and suppression of protein aggregation

KAUST Repository

Shah, Dhawal

2011-09-21

We examine the interaction of aromatic residues of proteins with arginine, an additive commonly used to suppress protein aggregation, using experiments and molecular dynamics simulations. An aromatic-rich peptide, FFYTP (a segment of insulin), and lysozyme and insulin are used as model systems. Mass spectrometry shows that arginine increases the solubility of FFYTP by binding to the peptide, with the simulations revealing the predominant association of arginine to be with the aromatic residues. The calculations further show a positive preferential interaction coefficient, Γ XP, contrary to conventional thinking that positive Γ XP\\'s indicate aggregation rather than suppression of aggregation. Simulations with lysozyme and insulin also show arginine\\'s preference for aromatic residues, in addition to acidic residues. We use these observations and earlier results reported by us and others to discuss the possible implications of arginine\\'s interactions with aromatic residues on the solubilization of aromatic moieties and proteins. Our results also highlight the fact that explanations based purely on Γ XP, which measures average affinity of an additive to a protein, could obscure or misinterpret the underlying molecular mechanisms behind additive-induced suppression of protein aggregation. © 2011 American Institute of Chemical Engineers (AIChE).

Arginine-aromatic interactions and their effects on arginine-induced solubilization of aromatic solutes and suppression of protein aggregation

KAUST Repository

Shah, Dhawal; Li, Jianguo; Shaikh, Abdul Rajjak; Rajagopalan, Raj

2011-01-01

We examine the interaction of aromatic residues of proteins with arginine, an additive commonly used to suppress protein aggregation, using experiments and molecular dynamics simulations. An aromatic-rich peptide, FFYTP (a segment of insulin), and lysozyme and insulin are used as model systems. Mass spectrometry shows that arginine increases the solubility of FFYTP by binding to the peptide, with the simulations revealing the predominant association of arginine to be with the aromatic residues. The calculations further show a positive preferential interaction coefficient, Γ XP, contrary to conventional thinking that positive Γ XP's indicate aggregation rather than suppression of aggregation. Simulations with lysozyme and insulin also show arginine's preference for aromatic residues, in addition to acidic residues. We use these observations and earlier results reported by us and others to discuss the possible implications of arginine's interactions with aromatic residues on the solubilization of aromatic moieties and proteins. Our results also highlight the fact that explanations based purely on Γ XP, which measures average affinity of an additive to a protein, could obscure or misinterpret the underlying molecular mechanisms behind additive-induced suppression of protein aggregation. © 2011 American Institute of Chemical Engineers (AIChE).

Fate and persistence of 14C pesticide residues in different soils: effects of 14C pesticide contaminated run-off soil water on biological systems. Part of a coordinated programme on isotopic-tracer-aided studies of agrochemical residue - soil biota interactions

International Nuclear Information System (INIS)

Lichtenstein, E.

1982-09-01

The interaction of selected fungicides, herbicides and N-fertilizers with microorganisms in cranberry soils and their effects on the degradation of 14 C-phenyl-parathion were investigated. Incubation of soils with parathion of p-nitrophenol for 4 days, followed by the addition of 14 C-parathion resulted after 24 h in an enhanced degradation of the insecticide to 14 CO 2 (34-39% of the applied radiocarbon as opposed to 2% in controls) and also in an increased binding of 14 C to the soil. The fungicide captafol inhibited the degradation of soil-applied 14 C-parathion as evidenced by a reduction of both 14 CO 2 evolution and 14 C-bound residues. Maneb and benomyl suppressed the degradation of 14 C-parathion to 14 CO 2 but not the formation of bound residues. Addition of 2,4-D to 14 C-parathion treated soil also resulted in an increased persistence of the insecticide. Studies conducted with the insecticide and (NH 4 ) 2 SO 4 , NH 4 NO 3 , KNO 3 or urea showed that under all experimental conditions the total amounts of 14 C recovered were similar, yet the distribution of 14 C-compounds into benzene-soluble, water-soluble and bound residues was not. This possibly indicated a change in the pathway of 14 C-parathion degradation. The insecticide was most persistent in soils containing (NH 4 ) 2 SO 4 , as demonstrated by a recovery of 29% of the applied radiocarbon in benzene-soluble form. Analyses by TIC of this benzene extraction phase revealed the presence of 14 C-parathion, 14 C-p-aminophenol and 14 C-aminoparathion

Deposition behavior of residual aluminum in drinking water distribution system: Effect of aluminum speciation.

Science.gov (United States)

Zhang, Yue; Shi, Baoyou; Zhao, Yuanyuan; Yan, Mingquan; Lytle, Darren A; Wang, Dongsheng

2016-04-01

Finished drinking water usually contains some residual aluminum. The deposition of residual aluminum in distribution systems and potential release back to the drinking water could significantly influence the water quality at consumer taps. A preliminary analysis of aluminum content in cast iron pipe corrosion scales and loose deposits demonstrated that aluminum deposition on distribution pipe surfaces could be excessive for water treated by aluminum coagulants including polyaluminum chloride (PACl). In this work, the deposition features of different aluminum species in PACl were investigated by simulated coil-pipe test, batch reactor test and quartz crystal microbalance with dissipation monitoring. The deposition amount of non-polymeric aluminum species was the least, and its deposition layer was soft and hydrated, which indicated the possible formation of amorphous Al(OH)3. Al13 had the highest deposition tendency, and the deposition layer was rigid and much less hydrated, which indicated that the deposited aluminum might possess regular structure and self-aggregation of Al13 could be the main deposition mechanism. While for Al30, its deposition was relatively slower and deposited aluminum amount was relatively less compared with Al13. However, the total deposited mass of Al30 was much higher than that of Al13, which was attributed to the deposition of particulate aluminum matters with much higher hydration state. Compared with stationary condition, stirring could significantly enhance the deposition process, while the effect of pH on deposition was relatively weak in the near neutral range of 6.7 to 8.7. Copyright © 2015. Published by Elsevier B.V.

Pesticide residues analysis in water samples of Nagarpur and Saturia Upazila, Bangladesh

Science.gov (United States)

Hasanuzzaman, M.; Rahman, M. A.; Islam, M. S.; Salam, M. A.; Nabi, M. R.

2018-03-01

Pesticides used to protect the crops from pest attack in the agricultural fields pose harmful effect to the non-target organisms such as human and many other aquatic and terrestrial organisms either directly or indirectly through food chain. The present study was conducted to monitor a total of seven pesticide residues under organochlorine, organophosphorus and carbamate pesticides in three different sources of pond water, paddy field water and tube-well water from Nagarpur Upazila and paddy field water in the company of Dhaleshwari and Gazikhali river water from Saturia Upazila, Bangladesh. A total of 40 water samples were analyzed using high-performance liquid chromatography equipped with ultraviolet detector. Among the organophosphorus pesticides, diazinon was detected in eight water samples at a concentration ranging from 4.11 to 257.91 μg/l whereas, malathion was detected only in one water sample at a concentration of 84.64 μg/l and chlorpyrifos pesticide was also detected only in one water sample and the concentration was 37.3 μg/l. Trace amount of carbaryl was identified but it was below the detection limit. None of the tested water samples was found to be contaminated with DDT or its metabolites (DDE and DDD). The water samples contaminated with the suspected pesticides were above the acceptable limit except for the fish pond samples of Sahabatpur and Dubaria union. To control the misuse of pesticides and to reduce the possible health risk, appropriate control systems of pests such as integrated pest management system should be implemented immediately by the authorities of the country.

Evaporation and condensation heat transfer in a suppression chamber of the water wall type passive containment cooling system

International Nuclear Information System (INIS)

Fujii, Tadashi; Kataoka, Yoshiyuki; Murase, Michio

1996-01-01

To evaluate the system pressure response of a water wall type containment cooling system, which is one of the passive safety systems, the evaporation and condensation behaviors in a suppression chamber have been experimentally examined. In the system, the suppression pool water evaporates from the pool surface, passing into the wetwell due to pool temperature rise, while steam in the wetwell condenses on the steel containment vessel wall due to the heat release through the wall. The wetwell is a gas phase region in the suppression chamber and its pressure, which is expressed as the sum of the noncondensable gas pressure and saturated steam pressure, is strongly affected by the evaporation heat transfer from the suppression pool surface and condensation heat transfer on the containment vessel wall. Based on the measured temperature profiles near the heat transfer surface and the wetwell pressure using two apparatuses, evaporation and condensation heat transfer coefficients were evaluated. The following results were obtained. (1) Both heat transfer coefficients increased as the ratio of the steam partial pressure to the total pressure increased. (2) Comparison of the results from two types of test apparatuses confirmed that the size of the heat transfer surface did not affect the heat transfer characteristics within these tests. (3) The heat transfer coefficients were expressed by the ratio of the steam to noncondensable gas logarithmic mean concentration, which considered the steam and gas concentration gradient from the heat transfer surface to the wetwell bulk. (author)

Investigation on reusing water treatment residuals to remedy soil contaminated with multiple metals in Baiyin, China

International Nuclear Information System (INIS)

Wang, Changhui; Zhao, Yuanyuan; Pei, Yuansheng

2012-01-01

Highlights: ► Fe/Al water treatment residuals (FARs) can stabilize As, Pb, Ni, Zn, Cr and Cu. ► FARs cannot stabilize Ba and Cd. ► The properties of FARs and soil affect the FARs’ ability of stabilizing metals. - Abstract: In this work, the remediation of soils contaminated with multiple metals using ferric and alum water treatment residuals (FARs) in Baiyin, China, was investigated. The results of metals fractionation indicated that after the soil was treated with FARs, arsenic (As), lead (Pb), nickel (Ni), zinc (Zn) and copper (Cu) could be transformed into more stable forms, i.e., As bound in crystalline Fe/Al oxides and other metals in the oxidable and residual forms. However, the forms of chromium (Cr) and cadmium (Cd) were unaffected. Interestingly, due to the effect of FARs, barium (Ba) was predominantly transformed into more mobile forms. The bioaccessibility extraction test demonstrated that the FARs reduced the bioaccessibility of As by 25%, followed by Cu, Cr, Zn, Ni and Pb. The bioaccessibility of Cd and Ba were increased; in particular, there was an increase of 41% for Ba at the end of the test. In conclusion, the FARs can be used to remedy soil contaminated with multiple metals, but comprehensive studies are needed before practical applications of this work.

Cradle-to-grave life cycle assessment of syngas electricity from woody biomass residues

Science.gov (United States)

Hongmei Gu; Richard Bergman

2017-01-01

Forest restoration and fire suppression activities in the western United States have resulted in large volumes of low-to-no value residues. An environmental assessment would enable greater use while maintaining environmental sustainability of these residues for energy products. One internationally accepted sustainable metric tool that can assess environmental impacts...

Water structure versus radical scavenger theories as explanations for the suppressive effects of DMSO and related compounds on radiation-induced transformation in vitro

Energy Technology Data Exchange (ETDEWEB)

Kennedy, A.R.; Symons, M.C.

1987-05-01

We report here that dimethylsulfoxide (DMSO): suppresses radiation-induced transformation in vitro, even when DMSO treatments begin as late as 10 days post-irradiation (when cells are in the confluent, stationary phase of growth); inhibits the 12-O-tetradecanoylphorbol-13-acetate (TPA) enhancement of radiation-induced transformation in vitro; does not affect the expression of transformed cells as foci (when surrounded by non-transformed cells); and may be affecting radiation-induced transformation through its solvent properties (i.e. the Water Structure theory), while its effects on the TPA enhancement of radiation transformation may be mediated by its free radical scavenging abilities. DMSO, dimethylformamide (DMF) and dimethylacetamide (DMA) are similar solvents which are all very effective in their ability to suppress radiation-induced transformation in vitro (at concentrations in the cellular media down to 0.01%). As DMSO is known to be an extremely effective OH. free-radical scavenging agent, while DMF and DMA are not as efficient at scavenging free radicals, our results suggest that properties other than free-radical scavenging ability may be important in the suppressive effects of these compounds on radiation-induced transformation in vitro. It is known that low concentrations of such basic aprotic solvents modify water structure so as to suppress the protic (H-bond donor) reactivity of water and enhance its basic (H-bond receptor) reactivity. These reactivity changes may well be responsible for the effects noted above. DMSO, DMF and DMA are also capable of suppressing the TPA enhancement of radiation transformation (at concentrations of the compounds of 0.1% or higher). For this effect, the ability of these compounds to scavenge OH. shows a general correlation with their ability to suppress the TPA enhancement of transformation, suggesting that the Radical Scavenger theory may explain the ability of DMSO to suppress promotion in vitro.

Separation of thorium (IV) from lanthanide concentrate (LC) and water leach purification (WLP) residue

International Nuclear Information System (INIS)

AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman

2014-01-01

Thorium (IV) content in industrial residue produced from rare earth elements production industry is one of the challenges to Malaysian environment. Separation of thorium from the lanthanide concentrate (LC) and Water Leach Purification (WLP) residue from rare earth elements production plant is described. Both materials have been tested by sulphuric acid and alkaline digestions. Th concentrations in LC and WLP were determined to be 1289.7 ± 129 and 1952.9±17.6 ppm respectively. The results of separation show that the recovery of Th separation from rare earth in LC after concentrated sulphuric acid dissolution and reduction of acidity to precipitate Th was found 1.76-1.20% whereas Th recovery from WLP was less than 4% after concentrated acids and alkali digestion processes. Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) was used to determine Th concentrations in aqueous phase during separation stages. This study indicated that thorium maybe exists in refractory and insoluble form which is difficult to separate by these processes and stays in WLP residue as naturally occurring radioactive material (NORM)

Water Extract from Spent Mushroom Substrate of Hericium erinaceus Suppresses Bacterial Wilt Disease of Tomato

Science.gov (United States)

Kwak, A Min; Min, Kyeong Jin; Lee, Sang Yeop

2015-01-01

Culture filtrates of six different edible mushroom species were screened for antimicrobial activity against tomato wilt bacteria Ralstonia solanacearum B3. Hericium erinaceus, Lentinula edodes (Sanjo 701), Grifola frondosa, and Hypsizygus marmoreus showed antibacterial activity against the bacteria. Water, n-butanol, and ethyl acetate extracts of spent mushroom substrate (SMS) of H. erinaceus exhibited high antibacterial activity against different phytopathogenic bacteria: Pectobacterium carotovorum subsp. carotovorum, Agrobacterium tumefaciens, R. solanacearum, Xanthomonas oryzae pv. oryzae, X. campestris pv. campestris, X. axonopodis pv. vesicatoria, X. axonopodis pv. citiri, and X. axonopodis pv. glycine. Quantitative real-time PCR revealed that water extracts of SMS (WESMS) of H. erinaceus induced expressions of plant defense genes encoding β-1,3-glucanase (GluA) and pathogenesis-related protein-1a (PR-1a), associated with systemic acquired resistance. Furthermore, WESMS also suppressed tomato wilt disease caused by R. solanacearum by 85% in seedlings and promoted growth (height, leaf number, and fresh weight of the root and shoot) of tomato plants. These findings suggest the WESMS of H. erinaceus has the potential to suppress bacterial wilt disease of tomato through multiple effects including antibacterial activity, plant growth promotion, and defense gene induction. PMID:26539048

Residual water transport in the Marsdiep tidal inlet inferred from observations and a numerical model

NARCIS (Netherlands)

Sassi, M.G.; Gerkema, T.; Duran-Matute, M.; Nauw, J.J.

2016-01-01

At tidal inlets, large amounts of water are exchanged with the adjacent sea during the tidal cycle.The residual flows, the net effect of ebb and flood, are generally small compared with the gross flux;they vary in magnitude and sign from one tidal period to the other; and their long-term mean

Residual water transport in the Marsdiep tidal inlet inferred from observations and a numerical model

NARCIS (Netherlands)

Sassi, M.G.; Gerkema, T.; Duran-Matute, M.; Nauw, J.J.

At tidal inlets, large amounts of water are exchanged with the adjacent sea during the tidal cycle. The residual flows, the net effect of ebb and flood, are generally small compared with the gross flux; they vary in magnitude and sign from one tidal period to the other; and their long-term mean

Polder effects on sediment-to-soil conversion: water table, residual available water capacity, and salt stress interdependence.

Science.gov (United States)

Radimy, Raymond Tojo; Dudoignon, Patrick; Hillaireau, Jean Michel; Deboute, Elise

2013-01-01

The French Atlantic marshlands, reclaimed since the Middle Age, have been successively used for extensive grazing and more recently for cereal cultivation from 1970. The soils have acquired specific properties which have been induced by the successive reclaiming and drainage works and by the response of the clay dominant primary sediments, that is, structure, moisture, and salinity profiles. Based on the whole survey of the Marais Poitevin and Marais de Rochefort and in order to explain the mechanisms of marsh soil behavior, the work focuses on two typical spots: an undrained grassland since at least 1964 and a drained cereal cultivated field. The structure-hydromechanical profiles relationships have been established thanks to the clay matrix shrinkage curve. They are confronted to the hydraulic functioning including the fresh-to-salt water transfers and to the recording of tensiometer profiles. The CE1/5 profiles supply the water geochemical and geophysical data by their better accuracy. Associated to the available water capacity calculation they allow the representation of the parallel evolution of the residual available water capacity profiles and salinity profiles according to the plant growing and rooting from the mesophile systems of grassland to the hygrophile systems of drained fields.

Structural analysis on mutation residues and interfacial water molecules for human TIM disease understanding

Science.gov (United States)

2013-01-01

Background Human triosephosphate isomerase (HsTIM) deficiency is a genetic disease caused often by the pathogenic mutation E104D. This mutation, located at the side of an abnormally large cluster of water in the inter-subunit interface, reduces the thermostability of the enzyme. Why and how these water molecules are directly related to the excessive thermolability of the mutant have not been investigated in structural biology. Results This work compares the structure of the E104D mutant with its wild type counterparts. It is found that the water topology in the dimer interface of HsTIM is atypical, having a "wet-core-dry-rim" distribution with 16 water molecules tightly packed in a small deep region surrounded by 22 residues including GLU104. These water molecules are co-conserved with their surrounding residues in non-archaeal TIMs (dimers) but not conserved across archaeal TIMs (tetramers), indicating their importance in preserving the overall quaternary structure. As the structural permutation induced by the mutation is not significant, we hypothesize that the excessive thermolability of the E104D mutant is attributed to the easy propagation of atoms' flexibility from the surface into the core via the large cluster of water. It is indeed found that the B factor increment in the wet region is higher than other regions, and, more importantly, the B factor increment in the wet region is maintained in the deeply buried core. Molecular dynamics simulations revealed that for the mutant structure at normal temperature, a clear increase of the root-mean-square deviation is observed for the wet region contacting with the large cluster of interfacial water. Such increase is not observed for other interfacial regions or the whole protein. This clearly suggests that, in the E104D mutant, the large water cluster is responsible for the subunit interface flexibility and overall thermolability, and it ultimately leads to the deficiency of this enzyme. Conclusions Our study

Recycling of drinking water treatment residue as an additional medium in columns for effective P removal from eutrophic surface water.

Science.gov (United States)

Wang, Changhui; Wu, Yu; Bai, Leilei; Zhao, Yaqian; Yan, Zaisheng; Jiang, Helong; Liu, Xin

2018-07-01

This study assesses the feasibility of recycling drinking water treatment residue (DWTR) to treat eutrophic surface water in a one-year continuous flow column test. Heat-treated DWTR was used as an additional medium (2%-4%) in columns in case excessive organic matter and N were released from the DWTR to surface water. The results indicated that with minimal undesirable effects on other water properties, DWTR addition substantially enhanced P removal, rendering P concentrations in treated water oligotrophic and treated water unsuitable for Microcystis aeruginosa breeding. Long-term stable P removal by DWTR-column treatment was mainly attributed to the relatively low P levels in raw water (cycles and multiple pollution control (e.g., Dechloromonas, Geobacter, Leucobacter, Nitrospira, Rhodoplanes, and Sulfuritalea); an apparent decrease in Mycobacterium with potential pathogenicity was observed in DWTR-columns. Regardless, limited denitrification of DWTR-columns was observed as a result of low bioavailability of C in surface water. This finding indicates that DWTR can be used with other methods to ensure denitrification for enhanced treatment effects. Overall, the use of DWTR as an additional medium in column systems can potentially treat eutrophic surface water. Copyright © 2018 Elsevier Ltd. All rights reserved.

Residual radioactivity guidelines for the heavy water components test reactor at the Savannah River Site

International Nuclear Information System (INIS)

Owen, M.B. Smith, R.; McNeil, J.

1997-04-01

Guidelines were developed for acceptable levels of residual radioactivity in the Heavy Water Components Test Reactor (HWCTR) facility at the conclusion of its decommissioning. Using source terms developed from data generated in a detailed characterization study, the RESRAD and RASRAD-BUILD computer codes were used to calculate derived concentration guideline levels (DCGLs) for the radionuclides that will remain in the facility. The calculated DCGLs, when compared to existing concentrations of radionuclides measured during a 1996 characterization program, indicate that no decontamination of concrete surfaces will be necessary. Also, based on the results of the calculations, activated concrete in the reactor biological shield does not have to be removed, and imbedded radioactive piping in the facility can remain in place. Viewed in another way, the results of the calculations showed that the present inventory of residual radioactivity in the facility (not including that associated with the reactor vessel and steam generators) would produce less than one millirem per year above background to a hypothetical individual on the property. The residual radioactivity is estimated to be approximately 0.04 percent of the total inventory in the facility as of March, 1997. According to the results, the only radionuclides that would produce greater than 0.0.1-millirem per year are Am-241 (0.013 mrem/yr at 300 years), C-14 (0.022 mrem/yr at 1000 years) and U-238 (0.034 mrem/yr at 6000 years). Human exposure would occur only through the groundwater pathways, that is, from water drawn from, a well on the property. The maximum exposure would be approximately one percent of the 4 millirem per year ground water exposure limit established by the U.S. Environmental Protection Agency. 11 refs., 13 figs., 15 tabs

Amendment of arsenic and chromium polluted soil from wood preservation by iron residues from water treatment

DEFF Research Database (Denmark)

Nielsen, Sanne Skov; Petersen, L. R.; Kjeldsen, Peter

2011-01-01

An iron-rich water treatment residue (WTR) consisting mainly of ferrihydrite was used for immobilization of arsenic and chromium in a soil contaminated by wood preservatives. A leaching batch experiment was conducted using two soils, a highly contaminated soil (1033mgkg−1 As and 371mgkg−1 Cr....... Pore water was extracted during 3years from the amended soil and a control site. Pore water arsenic concentrations in the amended soil were more than two orders of magnitude lower than in the control for the upper samplers. An increased release of arsenic was observed during winter in both fields...

Content Of 2,4-D-14C Herbicide Residue In Water And Soil Of Irrigated Rice Field System

International Nuclear Information System (INIS)

Chairul, Sofnie M.; Djabir, Elida; Magdalena, Nelly

2000-01-01

The investigation of 2,4-D exp.-14C herbicide residue in water and soil of irrigated rice field system was carried out. Rice plant and weeds (Monochoria vaginalis Burn. F. Presl) were planted in 101 buckets using two kinds of soil condition, I.e. normal soil and 30 % above normal compact soil. After one week planting, the plants were sprayed with 1 u Ci of 2,4-D exp.-14C and 0,4 mg non labeled 2,4-D. The herbicide residue content was determined 0, 2, 4, 8 and 10 weeks after spraying with 2,4-D herbicide. The analysis was done using Combustion Biological Oxidizer merk Harvey ox-400, and counted with Liquid Scintillation Counter merk Beckman model LS-1801. The results indicates that the herbicide contents in water and soil decrease from the first spraying with herbicide until harvest herbicide Residue content in water after harvest was 0.87 x 10 exp.-6 ppm for soil normal condition, and 0.59 x 10 exp.-6 pm for the soil 30 % up normal condition, while herbicide content in soil was 1.54 x 10 exp.-6 ppm for soil normal condition and 1.48 x 10 exp.-6 ppm for soil 30 % up normal. 2,4-D herbicide residue content in rice after harvest was 0.27 x 10 exp.-6 ppm for normal soil condition and 0.25 x 10 exp.-6 ppm for the soil 30 % up normal. 2,4-D herbicide residue content in roots and leaves of weeds after harvest were respectively 0.29 x 10 exp.-6 ppm and 0.18 x 10 exp.-6 for normal soil condition, while for 30 % up normal soil were 0.25 x 10 exp.-5 ppm and 0.63 x 10 exp.-7 ppm. This result indicates that there is no effect pollution to surrounding area, because the herbicide content is still bellow the allowed detection limit, 0.05 ppm

Removal of uranyl ions from residual waters using some algae types

International Nuclear Information System (INIS)

Cecal, A.; Palamaru, I.; Humelnicu, D.; Popa, K.; Salaru, V.V.; Rudic, V.; Gulea, A.

1999-01-01

This paper deals with a study on the bioaccumulation of uranyl ions resulted from residual effluents by means of some microbiological collectors: Scenedesmus quadricauda, Anabaena karakumica, Calothrix brevissima, Penicillinium sp, as well as the Glucid extract of Porphyridium cruentum, under various experimental conditions. The retaining degree of the bioaccumulated uranyl ions, as well as the leaching degree, in HCl and H 2 O media, of the same ions previously retained on algae were established. The retaining degree decreases in the series: Scenedesmus quadricauda > Anabaena karakumica > Penicillinium sp > Calothrix brevissima. The leaching effect of bioaccumulated uranyl ions is higher in hydrochloric acid than in water. (author)

Management of NORM Residues

International Nuclear Information System (INIS)

2013-06-01

The IAEA attaches great importance to the dissemination of information that can assist Member States in the development, implementation, maintenance and continuous improvement of systems, programmes and activities that support the nuclear fuel cycle and nuclear applications, and that address the legacy of past practices and accidents. However, radioactive residues are found not only in nuclear fuel cycle activities, but also in a range of other industrial activities, including: - Mining and milling of metalliferous and non-metallic ores; - Production of non-nuclear fuels, including coal, oil and gas; - Extraction and purification of water (e.g. in the generation of geothermal energy, as drinking and industrial process water; in paper and pulp manufacturing processes); - Production of industrial minerals, including phosphate, clay and building materials; - Use of radionuclides, such as thorium, for properties other than their radioactivity. Naturally occurring radioactive material (NORM) may lead to exposures at some stage of these processes and in the use or reuse of products, residues or wastes. Several IAEA publications address NORM issues with a special focus on some of the more relevant industrial operations. This publication attempts to provide guidance on managing residues arising from different NORM type industries, and on pertinent residue management strategies and technologies, to help Member States gain perspectives on the management of NORM residues

Investigation on reusing water treatment residuals to remedy soil contaminated with multiple metals in Baiyin, China

Energy Technology Data Exchange (ETDEWEB)

Wang, Changhui; Zhao, Yuanyuan [The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875 (China); Pei, Yuansheng, E-mail: yspei@bnu.edu.cn [The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875 (China)

2012-10-30

Highlights: Black-Right-Pointing-Pointer Fe/Al water treatment residuals (FARs) can stabilize As, Pb, Ni, Zn, Cr and Cu. Black-Right-Pointing-Pointer FARs cannot stabilize Ba and Cd. Black-Right-Pointing-Pointer The properties of FARs and soil affect the FARs' ability of stabilizing metals. - Abstract: In this work, the remediation of soils contaminated with multiple metals using ferric and alum water treatment residuals (FARs) in Baiyin, China, was investigated. The results of metals fractionation indicated that after the soil was treated with FARs, arsenic (As), lead (Pb), nickel (Ni), zinc (Zn) and copper (Cu) could be transformed into more stable forms, i.e., As bound in crystalline Fe/Al oxides and other metals in the oxidable and residual forms. However, the forms of chromium (Cr) and cadmium (Cd) were unaffected. Interestingly, due to the effect of FARs, barium (Ba) was predominantly transformed into more mobile forms. The bioaccessibility extraction test demonstrated that the FARs reduced the bioaccessibility of As by 25%, followed by Cu, Cr, Zn, Ni and Pb. The bioaccessibility of Cd and Ba were increased; in particular, there was an increase of 41% for Ba at the end of the test. In conclusion, the FARs can be used to remedy soil contaminated with multiple metals, but comprehensive studies are needed before practical applications of this work.

Dynamic interactions of the cortical networks during thought suppression.

Science.gov (United States)

Aso, Toshihiko; Nishimura, Kazuo; Kiyonaka, Takashi; Aoki, Takaaki; Inagawa, Michiyo; Matsuhashi, Masao; Tobinaga, Yoshikazu; Fukuyama, Hidenao

2016-08-01

Thought suppression has spurred extensive research in clinical and preclinical fields, particularly with regard to the paradoxical aspects of this behavior. However, the involvement of the brain's inhibitory system in the dynamics underlying the continuous effort to suppress thoughts has yet to be clarified. This study aims to provide a unified perspective for the volitional suppression of internal events incorporating the current understanding of the brain's inhibitory system. Twenty healthy volunteers underwent functional magnetic resonance imaging while they performed thought suppression blocks alternating with visual imagery blocks. The whole dataset was decomposed by group-independent component analysis into 30 components. After discarding noise components, the 20 valid components were subjected to further analysis of their temporal properties including task-relatedness and between-component residual correlation. Combining a long task period and a data-driven approach, we observed a right-side-dominant, lateral frontoparietal network to be strongly suppression related. This network exhibited increased fluctuation during suppression, which is compatible with the well-known difficulty of suppression maintenance. Between-network correlation provided further insight into the coordinated engagement of the executive control and dorsal attention networks, as well as the reciprocal activation of imagery-related components, thus revealing neural substrates associated with the rivalry between intrusive thoughts and the suppression process.

Dielectric properties of residual water in amorphous lyophilized mixtures of sugar and drug

Energy Technology Data Exchange (ETDEWEB)

Moznine, R El [School of Pharmacy, De Montfort University, Leiceste (United Kingdom); Smith, G [School of Pharmacy, De Montfort University, Leicester (United Kingdom); Polygalov, E [School of Pharmacy, De Montfort University, Leicester (United Kingdom); Suherman, P M [School of Pharmacy, De Montfort University, Leicester (United Kingdom); Broadhead, J [AstraZeneca Charnwood R and D, Bakewell Rd, Loughborough (United Kingdom)

2003-02-21

Dielectric relaxation spectroscopy was used to investigate the properties of residual water in lyophilized formulations of a proprietary tri-phosphate drug containing a sugar (trehalose, lactose or sucrose) or dextran. The dielectric properties of each formulation were determined in the frequency range (0.1 Hz-0.1 MHz) and temperature range (30 deg. C-T{sub g}). The temperature dependence of the relaxation times for all samples showed Arrhenuis behaviour, from which the activation energy was derived. Proton hopping through the hydrogen-bonded network (clusters) of water molecules was suggested as the principle mode of charge transport. Significant differences in dielectric relaxation kinetics and activation energy were observed for the different formulations, which were found to correlate with the amount of monophosphate degradation product.

Suppression/reducing method for total organic carbon in feedwater/condensate

International Nuclear Information System (INIS)

Maeda, Katsuharu.

1993-01-01

The present invention suppresses/reduces the concentration of the total organic carbon before the startup of a reactor, to decrease (TOC) which is brought into the reactor upon startup of the operation and suppress/moderate degradation of water quality of reactor water. That is, in-service period of a condensate desalting tower is shortened, to avoid concentration increase of TOC in feed water/condensate which is leached out from the condensate desalting tower. The condensate desalting towers are put to in-service for the entire towers after increasing the vacuum degree of the condensator, to suppress leaching of TOC from the condensate desalting tower. Further, upon startup of a nuclear power plant, when the condensate desalting tower is put to in-service, condensate filters of the entire towers are previously back-washed and regenerated to remove TOC efficiently. By these procedures, TOC brought from a water supply system upon startup of the plant is thermally decomposed or radiolyzed in the reactor, thereby enabling to suppress/avoid worsening of water quality of reactor water caused by generated ion impurities. (I.S.)

Removal of emulsified oil in residual waters by means of dissolved air flotation

International Nuclear Information System (INIS)

Echeverri Londono, Carlos Alberto

1996-01-01

In this article is consigned a theoretical and experimental study on the treatment of industrial residual waters with emulsified oil, through the flotation process for dissolved air (FAD), changing some operation parameters and some importance topics, related with the process. The experimental results and the theoretical pattern, show that the removal of oil depends fundamentally on the chemical pretreatment. Efficiencies of removal of oil up of 99% they were obtained, using the dissolved air flotation with the help of coagulants

Polder Effects on Sediment-to-Soil Conversion: Water Table, Residual Available Water Capacity, and Salt Stress Interdependence

Directory of Open Access Journals (Sweden)

Raymond Tojo Radimy

2013-01-01

Full Text Available The French Atlantic marshlands, reclaimed since the Middle Age, have been successively used for extensive grazing and more recently for cereal cultivation from 1970. The soils have acquired specific properties which have been induced by the successive reclaiming and drainage works and by the response of the clay dominant primary sediments, that is, structure, moisture, and salinity profiles. Based on the whole survey of the Marais Poitevin and Marais de Rochefort and in order to explain the mechanisms of marsh soil behavior, the work focuses on two typical spots: an undrained grassland since at least 1964 and a drained cereal cultivated field. The structure-hydromechanical profiles relationships have been established thanks to the clay matrix shrinkage curve. They are confronted to the hydraulic functioning including the fresh-to-salt water transfers and to the recording of tensiometer profiles. The CE1/5 profiles supply the water geochemical and geophysical data by their better accuracy. Associated to the available water capacity calculation they allow the representation of the parallel evolution of the residual available water capacity profiles and salinity profiles according to the plant growing and rooting from the mesophile systems of grassland to the hygrophile systems of drained fields.

Solid residues

International Nuclear Information System (INIS)

Mulder, E.; Duin, P.J. van; Grootenboer, G.J.

1995-01-01

A summary is presented of the many investigations that have been done on solid residues of atmospheric fluid bed combustion (AFBC). These residues are bed ash, cyclone ash and bag filter ash. Physical and chemical properties are discussed and then the various uses of residues (in fillers, bricks, gravel, and for recovery of aluminium) are summarised. Toxicological properties of fly ash and stack ash are discussed as are risks of pneumoconiosis for workers handling fly ash, and contamination of water by ashes. On the basis of present information it is concluded that risks to public health from exposure to emissions of coal fly ash from AFBC appear small or negligible as are health risk to workers in the coal fly ash processing industry. 35 refs., 5 figs., 12 tabs

Combination of chemical suppression techniques for dual suppression of fat and silicone at diffusion-weighted MR imaging in women with breast implants

Energy Technology Data Exchange (ETDEWEB)

Koh, Dow-Mu; Hughes, J. [Royal Marsden Hospital, Department of Radiology, Sutton (United Kingdom); Blackledge, M.; Leach, M.O.; Collins, D.J. [Institute of Cancer Research, CR UK-EPSRC Cancer Imaging Centre, Sutton (United Kingdom); Burns, S. [Nuada 3T MRI Centre, London (United Kingdom); Stemmer, A.; Kiefer, B. [Siemens Healthcare, Erlangen (Germany)

2012-12-15

Silicone breast prostheses prove technically challenging when performing diffusion-weighted MR imaging in the breasts. We describe a combined fat and chemical suppression scheme to achieve dual suppression of fat and silicone, thereby improving the quality of diffusion-weighted images in women with breast implants. MR imaging was performed at 3.0 and 1.5 T in women with silicone breast implants using short-tau inversion recovery (STIR) fat-suppressed echo-planar (EPI) diffusion-weighted MR imaging (DWI) on its own and combined with the slice-select gradient-reversal (SSGR) technique. Imaging was performed using dedicated breast imaging coils. Complete suppression of the fat and silicone signal was possible at 3.0 T using EPI DWI with STIR and SSGR, evaluated with dedicated breast coils. However, a residual silicone signal was still perceptible at 1.5 T using this combined approach. Nevertheless, a further reduction in silicone signal at 1.5 T could be achieved by employing thinner slice partitions and the addition of the chemical-selective fat-suppression (CHESS) technique. DWI using combined STIR and SSGR chemical suppression techniques is feasible to eliminate or reduce silicone signal from prosthetic breast implants. (orig.)

A Study on the Residual Stress Improvement of PWSCC(Primary Water Stress Corrosion Cracking) in DMW(Dissimilar Metal Weld)

International Nuclear Information System (INIS)

Kang, Sung Sik; Kim, Seok Hun; Lee, Seung Gun; Park, Heung Bae

2010-01-01

Since 2000s, most of the cracks are found in welds, especially in (DMW) dissimilar metal welds such as pressurizer safety relief nozzle, reactor head penetration, reactor bottom mounted instrumentation (BMI), and reactor nozzles. Even the cracks are revealed as a primary water stress corrosion cracking (PWSCC), it is difficult to find the cracks by current non destructive examination. The PWSCC is occurred by three incident factors, such as susceptible material, environmental corrosive condition, and welding residual stress. If one of the three factors can be erased or decreased, the PWSCC could be prevented. In this study, we performed residual stress analysis for DMW and several residual stress improvement methods. As the preventive methods of PWSCC, we used laser peening(IP) method, inlay weld(IW) method, and induction heating stress improvement(IHSI) method. The effect of residual stress improvement for preventive methods was compared and discussed by finite element modeling and residual stress of repaired DMW

Comparative analysis of different methods of extraction of present hydrocarbons in industrial residual waters

International Nuclear Information System (INIS)

Santa, Judith Rocio; Serrano, Martin; Stashenko, Elena

2002-01-01

A comparison among four extraction techniques such as: liquid - liquid (LLE) continuous and for lots, solid phase extraction (SPE), solid phase micro extraction (SPME) and static headspace (S-HS) was carried out. The main purpose of this research was to determine the highest recovery efficiencies and how reproducible the tests are while varying parameters such as time, extraction technique, type of solvents and others. Chromatographic parameters were optimized in order to carry out the analyses. Hydrocarbon's quantification of residual waters was achieved by using a high-resolution gas chromatography with a gas flame ionization detector (HRGC-FID). Validation of the method was carried out by analyzing real samples taken in different sampling places of the residual waters treatment plant of Ecopetrol - Barrancabermeja. The use of extraction methods that require big solvent quantities and long time for analysis are losing validity day by day. Techniques such as the HS-SPME and static HS are offered as alternatives for quantifying hydrocarbons. They show total lack of solvents, high sensibility, selectivity and the techniques are reproducible. Solid phase micro extraction (SPME) and static headspace (static HS) techniques were chosen as the extraction techniques to validate the method in real samples. Both techniques showed similar results for the determination of total hydrocarbons (in the gasoline range)

From municipal sewage to drinking water: fate and removal of pharmaceutical residues in the aquatic environment in urban areas.

Science.gov (United States)

Heberer, Th; Reddersen, K; Mechlinski, A

2002-01-01

Recently, the occurrence and fate of pharmaceutically active compounds (PhACs) in the aquatic environment was recognized as one of the emerging issues in environmental chemistry and as a matter of public concern. Residues of PhACs have been found as contaminants in sewage, surface, and ground- and drinking water samples. Since June 2000, a new long-term monitoring program of sewage, surface, ground- and drinking water has been carried out in Berlin, Germany. Samples, collected periodically from selected sites in the Berlin area, are investigated for residues of PhACs and related contaminants. The purpose of this monitoring is to investigate these compounds over a long time period to get more reliable data on their occurrence and fate in the different aquatic compartments. Moreover, the surface water investigations allow the calculation of season-dependent contaminant loads in the Berlin waters. In the course of the monitoring program, PhACs and some other polar compounds were detected at concentrations up to the microg/L-level in all compartments of the Berlin water cycle. The monitoring is accompanied and supported by several other investigations such as laboratory column experiments and studies on bank filtration and drinking water treatment using conventional or membrane filtration techniques.

Drug residues in urban water: A database for ecotoxicological risk management.

Science.gov (United States)

Destrieux, Doriane; Laurent, François; Budzinski, Hélène; Pedelucq, Julie; Vervier, Philippe; Gerino, Magali

2017-12-31

Human-use drug residues (DR) are only partially eliminated by waste water treatment plants (WWTPs), so that residual amounts can reach natural waters and cause environmental hazards. In order to properly manage these hazards in the aquatic environment, a database is made available that integrates the concentration ranges for DR, which cause adverse effects for aquatic organisms, and the temporal variations of the ecotoxicological risks. To implement this database for the ecotoxicological risk assessment (ERA database), the required information for each DR is the predicted no effect concentrations (PNECs), along with the predicted environmental concentrations (PECs). The risk assessment is based on the ratio between the PNECs and the PECs. Adverse effect data or PNECs have been found in the publicly available literature for 45 substances. These ecotoxicity test data have been extracted from 125 different sources. This ERA database contains 1157 adverse effect data and 287 PNECs. The efficiency of this ERA database was tested with a data set coming from a simultaneous survey of WWTPs and the natural environment. In this data set, 26 DR were searched for in two WWTPs and in the river. On five sampling dates, concentrations measured in the river for 10 DR could pose environmental problems of which 7 were measured only downstream of WWTP outlets. From scientific literature and measurements, data implementation with unit homogenisation in a single database facilitates the actual ecotoxicological risk assessment, and may be useful for further risk coming from data arising from the future field survey. Moreover, the accumulation of a large ecotoxicity data set in a single database should not only improve knowledge of higher risk molecules but also supply an objective tool to help the rapid and efficient evaluation of the risk. Copyright © 2017 Elsevier B.V. All rights reserved.

Insights into the mechanisms of mercury sorption onto aluminum based drinking water treatment residuals

Energy Technology Data Exchange (ETDEWEB)

Deliz Quiñones, Katherine, E-mail: Katherine.Deliz@amecfw.com; Hovsepyan, Anna, E-mail: anna_Hovsepyan@urscorp.com; Oppong-Anane, Akua; Bonzongo, Jean-Claude J., E-mail: bonzongo@ufl.edu

2016-04-15

Highlights: • Mercury sorption by Al-WTRs involves electrostatic forces and chemisorption. • Hg forms bonds with oxygen and sulfur atoms of Al-WTR’s organic ligands. • Mercury is incorporated into the residual fraction to form stable complexes. • Mercury binds mainly to SiO{sub x} species in the residual fraction. - Abstract: Several studies have demonstrated the ability of drinking water treatment residuals (WTRs) to efficiently sorb metal cations from aqueous solutions. Reported results have stimulated interest on the potential use of WTRs as sorbent for metal removal from contaminated aqueous effluents as well as in metal immobilization in contaminated soils. However, knowledge on mechanisms of metal sorption by WTRs remains very limited and data on the long-term stability of formed metal–WTR complexes as a function of changing key environmental parameters are lacking. In this study, chemical selective sequential extraction (SSE), scanning electron microscopy combined with X-ray energy dispersive spectrometer (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) were used to gain insight into the different mechanisms of mercury (Hg) binding to aluminum based WTR (Al-WTRs). Results from sorption studies show that a significant portion of Hg becomes incorporated in the operationally defined residual fraction of Al-WTRs, and therefore, not prone to dissolution and mobility. The results of solid phase analyses suggested that Hg immobilization by Al-WTR occurs largely through its binding to oxygen donor atoms of mineral ligands driven by a combination of electrostatic forces and covalent bonding.

Insights into the mechanisms of mercury sorption onto aluminum based drinking water treatment residuals

International Nuclear Information System (INIS)

Deliz Quiñones, Katherine; Hovsepyan, Anna; Oppong-Anane, Akua; Bonzongo, Jean-Claude J.

2016-01-01

Highlights: • Mercury sorption by Al-WTRs involves electrostatic forces and chemisorption. • Hg forms bonds with oxygen and sulfur atoms of Al-WTR’s organic ligands. • Mercury is incorporated into the residual fraction to form stable complexes. • Mercury binds mainly to SiO x species in the residual fraction. - Abstract: Several studies have demonstrated the ability of drinking water treatment residuals (WTRs) to efficiently sorb metal cations from aqueous solutions. Reported results have stimulated interest on the potential use of WTRs as sorbent for metal removal from contaminated aqueous effluents as well as in metal immobilization in contaminated soils. However, knowledge on mechanisms of metal sorption by WTRs remains very limited and data on the long-term stability of formed metal–WTR complexes as a function of changing key environmental parameters are lacking. In this study, chemical selective sequential extraction (SSE), scanning electron microscopy combined with X-ray energy dispersive spectrometer (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) were used to gain insight into the different mechanisms of mercury (Hg) binding to aluminum based WTR (Al-WTRs). Results from sorption studies show that a significant portion of Hg becomes incorporated in the operationally defined residual fraction of Al-WTRs, and therefore, not prone to dissolution and mobility. The results of solid phase analyses suggested that Hg immobilization by Al-WTR occurs largely through its binding to oxygen donor atoms of mineral ligands driven by a combination of electrostatic forces and covalent bonding.

Alternatives to crop residues for soil amendment

OpenAIRE

Powell, J.M.; Unger, P.W.

1997-01-01

Metadata only record In semiarid agroecosystems, crop residues can provide important benefits of soil and water conservation, nutrient cycling, and improved subsequent crop yields. However, there are frequently multiple competing uses for residues, including animal forage, fuel, and construction material. This chapter discusses the various uses of crop residues and examines alternative soil amendments when crop residues cannot be left on the soil.

Structural Characterization and Antioxidative Activity of Low-Molecular-Weights Beta-1,3-Glucan from the Residue of Extracted Ganoderma lucidum Fruiting Bodies

Directory of Open Access Journals (Sweden)

Pai-Feng Kao

2012-01-01

Full Text Available The major cell wall constituent of Ganoderma lucidum (G. lucidum is β-1,3-glucan. This study examined the polysaccharide from the residues of alkaline-extracted fruiting bodies using high-performance anion-exchange chromatography (HPAEC, and it employed nuclear magnetic resonance (NMR and mass spectrometry (MS to confirm the structures. We have successfully isolated low-molecular-weight β-1,3-glucan (LMG, in high yields, from the waste residue of extracted fruiting bodies of G. lucidum. The 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT assay evaluated the capability of LMG to suppress H2O2-induced cell death in RAW264.7 cells, identifying that LMG protected cells from H2O2-induced damage. LMG treatment decreased H2O2-induced intracellular reactive oxygen species (ROS production. LMG also influenced sphingomyelinase (SMase activity, stimulated by cell death to induce ceramide formation, and then increase cell ROS production. Estimation of the activities of neutral and acid SMases in vitro showed that LMG suppressed the activities of both neutral and acid SMases in a concentration-dependent manner. These results suggest that LMG, a water-soluble β-1,3-glucan recycled from extracted residue of G. lucidum, possesses antioxidant capability against H2O2-induced cell death by attenuating intracellular ROS and inhibiting SMase activity.

Residues in the alternative reading frame tumor suppressor that influence its stability and p53-independent activities

International Nuclear Information System (INIS)

Tommaso, Anne di; Hagen, Jussara; Tompkins, Van; Muniz, Viviane; Dudakovic, Amel; Kitzis, Alain; Ladeveze, Veronique; Quelle, Dawn E.

2009-01-01

The Alternative Reading Frame (ARF) protein suppresses tumorigenesis through p53-dependent and p53-independent pathways. Most of ARF's anti-proliferative activity is conferred by sequences in its first exon. Previous work showed specific amino acid changes occurred in that region during primate evolution, so we programmed those changes into human p14ARF to assay their functional impact. Two human p14ARF residues (Ala 14 and Thr 31 ) were found to destabilize the protein while two others (Val 24 and Ala 41 ) promoted more efficient p53 stabilization and activation. Despite those effects, all modified p14ARF forms displayed robust p53-dependent anti-proliferative activity demonstrating there are no significant biological differences in p53-mediated growth suppression associated with simian versus human p14ARF residues. In contrast, p53-independent p14ARF function was considerably altered by several residue changes. Val 24 was required for p53-independent growth suppression whereas multiple residues (Val 24 , Thr 31 , Ala 41 and His 60 ) enabled p14ARF to block or reverse the inherent chromosomal instability of p53-null MEFs. Together, these data pinpoint specific residues outside of established p14ARF functional domains that influence its expression and signaling activities. Most intriguingly, this work reveals a novel and direct role for p14ARF in the p53-independent maintenance of genomic stability.

METHOD 332.0: DETERMINATION OF PERCHLORATE IN DRINKING WATER BY ION CHROMATOGRAPHY WITH SUPPRESSED CONDUCTIVITY AND ELECTROSPRAY IONIZATION MASS SPECTROMETRY

Science.gov (United States)

This method is applicable to the identification and quantitation of perchlorate in raw and finished drinking waters. The approach used is ion chromatography with suppressed conductivity and electrospray ionization mass spectrometry (IC-ESI/MS)

Presence of pesticide residues in water, sediment and biological samples taken from aquatic environments in Honduras

International Nuclear Information System (INIS)

Meyer, D.E.

1999-01-01

The objective of this study was to detect the presence of persistent pesticides in water, sediment and biological samples taken from aquatic environments in Honduras during the period 1995-98. Additionally, the LC 50 for 2 fungicides and 2 insecticides on post-larval Penaeus vannamei was determined in static water bioassays. A total of 80 water samples, 16 sediment samples and 7 biological samples (fish muscle tissue) were analyzed for detection of organochlorine and organophosphate pesticide residues. The results of sample analyses indicate a widespread contamination of Honduran continental and coastal waters with organochlorine pesticides. Most detections were of low ( 50 values and were therefore found to be much more toxic to the post-larval shrimp than the fungicides tridemorph and propiconazole. (author)

Effect of Residual Strain on PWSCC Initiation of Alloy 690 in Primary Water of PWR

International Nuclear Information System (INIS)

Lee, Eun-Hee; Kim, Sung-Woo; Eom, Ki-Hyeon; Hwang, Seong-Sik

2016-01-01

The object of this study is to attempt to correlate the susceptibility to crack initiation of Alloy 690 with the levels of cold work in simulated primary water. Experiments were conducted in high-temperature water to accelerate the cracking behavior and to determine the severity of crack initiation as a function of level of cold work for Alloy 690. Cracking susceptibility was determined by measuring the crack length per unit area and crack density. SCC initiation susceptibility of Alloy 690 increased with increase of the residual strain induced by the prior cold-rolling process. The 20% cold-rolled specimen exhibited mostly IG cracks, while the 30% and 40% cold-rolled specimens revealed significant amounts of IG and TG cracks. Most cracks were observed near the smallest cross-section area of the tapered specimen, where the maximum stress was applied, indicating that the SCC initiation susceptibility was strongly dependent on the applied stress. In order to find the correlation between SCC initiation susceptibility and residual strain induced by cold work, more analyses need to be performed in terms of the crack length per unit area and the crack density, as a strong indicative for SCC initiation susceptibility

Treatment of drinking water residuals: comparing sedimentation and dissolved air flotation performance with optimal cation ratios.

Science.gov (United States)

Bourgeois, J C; Walsh, M E; Gagnon, G A

2004-03-01

Spent filter backwash water (SFBW) and clarifier sludge generally comprise the majority of the waste residual volume generated and in relative terms, these can be collectively referred to as combined filter backwash water (CFBW). CFBW is essentially a low-solids wastewater with metal hydroxide flocs that are typically light and slow to settle. This study evaluates the impact of adding calcium and magnesium carbonates to CFBW in terms of assessing the impacts on the sedimentation and DAF separation processes. Representative CFBW samples were collected from two surface water treatment plants (WTP): Lake Major WTP (Dartmouth, Nova Scotia, Canada) and Victoria Park WTP (Truro, Nova Scotia, Canada). Bench-scale results indicated that improvements in the CFBW settled water quality could be achieved through the addition of the divalent cations, thereby adjusting the monovalent to divalent (M:D) ratios of the wastewater. In general, the DAF process required slightly higher M:D ratios than the sedimentation process. The optimum M:D ratios for DAF and sedimentation were determined to be 1:1 and 0.33:1, respectively. It was concluded that the optimisation of the cation balance between monovalent cations (e.g., Na(+), K(+)) and added divalent cations (i.e., Ca(2+), Mg(2+)) aided in the settling mechanism through charge neutralisation-precipitation. The increase in divalent cation concentrations within the waste residual stream promoted destabilisation of the negatively charged colour molecules within the CFBW, thereby causing the colloidal content to become more hydrophobic.

Cl app: android-based application program for monitoring the residue chlorine in water

Science.gov (United States)

Intaravanne, Yuttana; Sumriddetchkajorn, Sarun; Porntheeraphat, Supanit; Chaitavon, Kosom; Vuttivong, Sirajit

2015-07-01

A farmer usually uses a cheap chemical material called chlorine to destroy the cell structure of unwanted organisms and remove some plant effluents in a baby shrimp farm. A color changing of the reaction between chlorine and chemical indicator is used to monitor the residue chlorine in water before releasing a baby shrimp into a pond. To get rid of the error in color reading, our previous works showed how a smartphone can be functioned as a color reader for estimating the chlorine concentration in water. In this paper, we show the improvement of interior configuration of our prototype and the distribution to several baby shrimp farms. In the future, we plan to make it available worldwide through the online market as well as to develop more application programs for monitoring other chemical substances.

ALLELOPATHIC EFFECT OF PARSLEY (Petroselinum crispum Mill. COGERMINATION, WATER EXTRACTS AND RESIDUES ON HOARY CRESS (Lepidium draba (L. Desv.

Directory of Open Access Journals (Sweden)

Marija Ravlić

2014-06-01

Full Text Available The aim of the study was to examine allelopathic effect of parsley (Petroselinum crispum Mill. on germination and growth parameters of weed species hoary cress (Lepidium draba (L. Desv.. Cogermination of hoary cress with parsley seeds, water extracts from fresh and dry parsley biomass in concentrations of 5 and 10% (50 and 100 g per litre of distilled water were evaluated in Petri dishes. Effect of water extracts from fresh parsley biomass in aforementioned concentrations as well as effects of fresh and dry parsley residues in two rates (10 and 20 g/kg of soil were examined in pots with soil. Cogermination of seeds stimulated root length, but decreased shoot length and fresh weight of hoary cress seedlings. In the Petri dish assay, extracts from fresh and dry parsley biomass reduced germination of hoary cress, but had both stimulatory as well as inhibitory effect on other parameters. The highest concentration of dry biomass extract completely reduced germination rate of hoary cress (by 100%. In the pot experiment, extracts from fresh parsley biomass had stimulatory effect on weed growth parameters except for root length which was inhibited with higher concentration by 4.2%. Fresh parsley residues reduced germination, root and shoot length of hoary cress, while dry parsley residues promoted measured parameters, with the exception of root length.

Drug residues and endocrine disruptors in drinking water: risk for humans?

Science.gov (United States)

Touraud, Evelyne; Roig, Benoit; Sumpter, John P; Coetsier, Clémence

2011-11-01

The presence of pharmaceuticals and endocrine disruptors in the environment raises many questions about risk to the environment and human health. Environmental exposure has been largely studied, providing to date a realistic picture of the degree of contamination of the environment by pharmaceuticals and hormones. Conversely, little information is available regarding human exposure. NSAIDS, carbamazepine, iodinated contrast media, β-blockers, antibiotics have been detected in drinking water, mostly in the range of ng/L. it is questioned if such concentrations may affect human health. Currently, no consensus among the scientific community exists on what risk, if any, pharmaceuticals and endocrine disruptors pose to human health. Future European research will focus, on one hand, on genotoxic and cytotoxic anti-cancer drugs and, on the other hand, on the induction of genetic resistance by antibiotics. This review does not aim to give a comprehensive overview of human health risk of drug residues and endocrine disruptors in drinking water but rather highlight important topics of discussion. Copyright © 2011. Published by Elsevier GmbH.

Photographic and video techniques used in the 1/5-scale Mark I boiling water reactor pressure suppression experiment

International Nuclear Information System (INIS)

Dixon, D.; Lord, D.

1978-01-01

The report provides a description of the techniques and equipment used for the photographic and video recordings of the air test series conducted on the 1/5 scale Mark I boiling water reactor (BWR) pressure suppression experimental facility at Lawrence Livermore Laboratory (LLL) between March 4, 1977, and May 12, 1977. Lighting and water filtering are discussed in the photographic system section and are also applicable to the video system. The appendices contain information from the photographic and video camera logs

Organophosphorus and Carbamate Pesticide Residues Detected in Water Samples Collected from Paddy and Vegetable Fields of the Savar and Dhamrai Upazilas in Bangladesh

Directory of Open Access Journals (Sweden)

Nurul Karim

2012-09-01

Full Text Available Several types of organophosphorous and carbamate pesticides have been used extensively by the farmers in Bangladesh during the last few decades. Twenty seven water samples collected from both paddy and vegetable fields in the Savar and Dhamrai Upazilas in Bangladesh were analyzed to determine the occurrence and distribution of organo-phosphorus (chlorpyrifos, malathion and diazinon and carbamate (carbaryl and carbofuran pesticide residues. A high performance liquid chromatograph instrument equipped with a photodiode array detector was used to determine the concentrations of these pesticide residues. Diazinon and carbofuran were detected in water samples collected from Savar Upazila at 0.9 μg/L and 198.7 μg/L, respectively. Malathion was also detected in a single water sample at 105.2 μg/L from Dhamrai Upazila. Carbaryl was the most common pesticide detected in Dhamrai Upazila at 14.1 and 18.1 μg/L, while another water sample from Dhamrai Upazila was contaminated with carbofuran at 105.2 μg/L. Chlorpyrifos was not detected in any sample. Overall, the pesticide residues detected were well above the maximum acceptable levels of total and individual pesticide contamination, at 0.5 and 0.1 μg/L, respectively, in water samples recommended by the European Economic Community (Directive 98/83/EC. The presence of these pesticide residues may be attributed by their intense use by the farmers living in these areas. Proper handling of these pesticides should be ensured to avoid direct or indirect exposure to these pesticides.

Investigation of Pharmaceutical Residues in Hospital Effluents, in Ground- and Drinking Water from Bundeswehr Facilities, and their Removal During Drinking Water Purification (Arzneimittelrueckstaende in Trinkwasser(versorgungsanlagen) und Krankenhausabwaessern der Bundeswehr: Methodenentwicklung - Verkommen - Wasseraufbereitung)

National Research Council Canada - National Science Library

Heberer, Th; Feldmann, Dirk; Adam, Marc; Reddersen, Kirsten

1999-01-01

... by the German Ministry of Defense. The project had three defined objectives including the investigation of pharmaceutical residues in ground water wells used for drinking water supply at military facilities...

Effects of neutron radiation and residual stresses on the corrosion of welds in light water reactor internals

International Nuclear Information System (INIS)

Schaaf, Bob van der; Gavillet, Didier; Lapena, Jesus; Ohms, Carsten; Roth, Armin; Dyck, Steven van

2006-01-01

After many years of operation in Light Water Reactors (LWR) Irradiation Assisted Stress Corrosion Cracking (IASCC) of internals has been observed. In particular the heat-affected zone (HAZ) has been associated with IASCC attack. The welding process induces residual stresses and micro-structural modifications. Neutron irradiation affects the materials response to mechanical loading. IASCC susceptibility of base materials is widely studied, but the specific conditions of irradiated welds are rarely assessed. Core component relevant welds of Type 304 and 347 steels have been fabricated and were irradiated in the High Flux Reactor (HFR) in Petten to 0.3 and 1 dpa (displacement per atom). In-service welds were cut from the thermal shield of the decommissioned BR-3 reactor. Residual stresses, measured using neutron diffraction, ring core tests and X-ray showed residual stress levels up to 400 MPa. Micro-structural characterization showed higher dislocation densities in the weld and HAZ. Neutron radiation increased the dislocation density, resulting in hardening and reduced fracture toughness. The sensitization degree of the welds, measured with the electrochemical potentio-dynamic reactivation method, was negligible. The Slow Strain Rate Tensile (SSRT) tests, performed at 290 deg. C in water with 200 ppb dissolved oxygen, (DO), did not reveal inter-granular cracking. Inter-granular attack of in-service steel is observed in water with 8 ppm (DO), attributed not only to IASCC, but also to IGSCC from thermal sensitization during fabrication. Stress-relieve annealing has caused Cr-grain boundary precipitation, indicating the sensitization. The simulated internal welds, irradiated up to 1.0 dpa, did not show inter-granular cracking with 8 ppm DO. (authors)

Cleaning of the equipment of residual sodium by means of water-vacuum technology

International Nuclear Information System (INIS)

Klykov, B.P.; Lednev, A.I.

1997-01-01

Results of investigation into a problem of equipment decontamination from sodium, that have been conducted in OKBM since 1960 are given. The investigations performed have shown that a water-vacuum washing process is the most optimal method for equipment decontamination from sodium residues. The essence of the method is in conduction of sodium-water reaction under reduced pressure in a leak-tight tank. Boundary conditions are selected experimentally which not allow sodium to be melted during the process, that gives possibility to control the sodium-water reaction. Continuous removal of H 2 and reaction products creates safe conditions for the process conduction. More that 20-year period of operation of a stationary water-vacuum facility and washing the electromagnetic pump for BN-350 fast nuclear reactor directly at is test rig are the best proofs of the proposed method. This method is well suitable for washing the equipment contaminated by radioactive sodium, because by-products of the process are simply utilized. The method is used in a number of Russian enterprises, and recommended for implementation at BN-350 and BN-600 reactor plants. (author)

Treatment of residual waters of slaughterhouses with filters

International Nuclear Information System (INIS)

Ortiz A, Jesus Mario

1995-01-01

For studying the anaerobic treatment of the residual waters coming from a slaughterhouse of bovine livestock, they were used a system of two filters in series and a third unique filter as witness. With values average of load organic volumetric and time of retention of 1.6 kg/(m 3 d) and 26 hours respectively, the efficiencies of removal of total DQO were similar in the unique filter and in the system in series, of the order of 64% on the average. Likewise, the retention and accumulation of biological solids in the channel were shown as the main road of removal of the DQO. The differentiation of the process achieved with the two filters in series allowed establishing that most of the accumulation happened in the primary filter, as long as the fundamental of the bioconversion in methane took place in the secondary filter of the system in series. The first relative level of methanegenization obtained could be explained by the limitations to the activity of the methanogenic biomass imposed by the low temperatures, although it could not discard a probable inhibition for the hydrolysis products of the accumulated fats

Pressure suppression device for a reactor container

International Nuclear Information System (INIS)

Shimizu, Toshiaki

1982-01-01

Purpose: To prevent damages in drain pipes or the likes upon the water level increase due to blowing of incompressible gases. Constitution: An exhaust pipe for guiding escaping steams is connected to a main steam releaf valve. The exhaust pipe is guided into pressure-suppression-chamber water through the inside of a dry-well and by way of a vent pipe, a vent header and a drain pipe or a downcomer. Since the exhaust pipe is not exposed to the water surface inside the pressure suppression chamber, even if steams blow out into the dry-well by the rapture of pipeways or the likes to rapidly increase the water level, the water surface does not hit on the exhaust pipe, whereby the damages for the exhaust pipe and support members can be prevented to improve the reliability. (Seki, T.)

ANALYSIS OF THE LEACHING EFFICIENCY OF INHIBITED WATER AND TANK 23H SIMULANT IN REMOVING RESIDUES ON TANK 48H WALLS

International Nuclear Information System (INIS)

Fondeur, F; Thomas02 White, T; Lawrence Oji, L; Chris Martino, C; Bill Wilmarth, B

2006-01-01

Solid residues on two sets of thermowell pipe samples from the D2 riser in SRS Tank 48H were characterized. The residue thickness was determined using the ASTM standard D 3483-05 and was found to be three order of magnitudes below the 1mm thickness estimated from an earlier video of the tank cooling coil inspection. The actual estimated thickness ranged from 4 to 20.4 microns. The mass per unit area ranged from 1 to 5.3 milligrams per square inch. The residues appear to consist primarily of potassium tetraphenylborate (39.8 wt% KTPB) and dried salt solution (33.5 wt% total of nitrates, nitrites and oxalate salts), although ∼30% of the solid mass was not accounted for in the mass balance. No evidence of residue buildup was found inside the pipe, as expected. The residue leaching characteristics were measured by placing one pipe in inhibited water and one pipe in DWPF Recycle simulant. After soaking for less than 4 weeks, the inhibited water was 95.4% effective at removing the residue and the DWPF Recycle simulant was 93.5% effective. The surface appearance of the pipes after leaching tests appeared close to the clean shiny appearance of a new pipe. Total gamma counts of leachates averaged 48.1 dpm/ml, or an equivalent of 2.35E-11 Ci/gm Cs-137 (dry solids basis), which is much lower than the 1.4 E-03 Ci/gm expected for Tank 48 dry slurry solids

Use of life cycle assessment as decision-support tool for water reuse and handling of residues at a Danish industrial laundry

DEFF Research Database (Denmark)

Jørgensen, Kim; Villanueva, Alejandro; Wenzel, Henrik

2004-01-01

. Heavy metals originate from the dirt in the workwear that is washed in the laundry. It is further concluded that the studied water treatment technologies satisfy both the need of clean water for recycling and simultaneously help controlling a safe disposal of pollutants by concentration of the residues...

Two Novel Motifs of Watermelon Silver Mottle Virus NSs Protein Are Responsible for RNA Silencing Suppression and Pathogenicity.

Science.gov (United States)

Huang, Chung-Hao; Hsiao, Weng-Rong; Huang, Ching-Wen; Chen, Kuan-Chun; Lin, Shih-Shun; Chen, Tsung-Chi; Raja, Joseph A J; Wu, Hui-Wen; Yeh, Shyi-Dong

2015-01-01

The NSs protein of Watermelon silver mottle virus (WSMoV) is the RNA silencing suppressor and pathogenicity determinant. In this study, serial deletion and point-mutation mutagenesis of conserved regions (CR) of NSs protein were performed, and the silencing suppression function was analyzed through agroinfiltration in Nicotiana benthamiana plants. We found two amino acid (aa) residues, H113 and Y398, are novel functional residues for RNA silencing suppression. Our further analyses demonstrated that H113 at the common epitope (CE) ((109)KFTMHNQ(117)), which is highly conserved in Asia type tospoviruses, and the benzene ring of Y398 at the C-terminal β-sheet motif ((397)IYFL(400)) affect NSs mRNA stability and protein stability, respectively, and are thus critical for NSs RNA silencing suppression. Additionally, protein expression of other six deleted (ΔCR1-ΔCR6) and five point-mutated (Y15A, Y27A, G180A, R181A and R212A) mutants were hampered and their silencing suppression ability was abolished. The accumulation of the mutant mRNAs and proteins, except Y398A, could be rescued or enhanced by co-infiltration with potyviral suppressor HC-Pro. When assayed with the attenuated Zucchini yellow mosaic virus vector in squash plants, the recombinants carrying individual seven point-mutated NSs proteins displayed symptoms much milder than the recombinant carrying the wild type NSs protein, suggesting that these aa residues also affect viral pathogenicity by suppressing the host silencing mechanism.

Bacillus cereus as indicator in the sterilization of residual water with high energy electrons; Bacillus cereus como indicador en la desinfeccion de aguas residuales con electrones de alta energia

Energy Technology Data Exchange (ETDEWEB)

Mejia Z, E

2000-07-01

One of the main causes of water pollution is the presence of microorganisms that provoke infections, moreover of chemical substances. The processes of residual water treatment finally require of the disinfection for its use or final disposition. The radiation technology for the residual water treatment by mean of electron beams is an innovator process because as well as decomposing the chemical substance or to degrade them, also it provokes a disinfection by which this is proposed as alternative for disinfection of residual water, with the purpose in reusing the water treated in the agriculture, recreation and industry among others secondary activities, solving environmental or health problems. The objective of this work is to evaluate the use of Bacillus cereus as biological indicator in the disinfection by radiation, using High Energy Electrons. To fulfil with this objective, the work was developed in three stages, the first one consisted in the acquisition, propagation and conservation of the Bacillus cereus stumps, considering Escherichia coli and Salmonella typhimurium as pathogenic germs present in residual water. Moreover, the inocule standardization and the conditions of the Electron accelerator Type Pelletron. In the second stage it was performed the irradiation of aqueous samples of the microorganisms simulating biological pollution and the application to problem samples of a treatment plant sited in the Lerma River zone of mixed residual water. And in the third stage was performed a regression analysis to the reported survival for each kind of microorganisms. The results obtained show that with the use of Electron beams was reduced 6 logarithmic units de E. coli at 129 Gy, for S. typhimurium it was reduced 8 logarithmic units at 383 Gy and the B. cereus at 511 Gy was reduced 6.8 logarithmic units. Of the problem samples irradiated at 500 Gy, the concentration of the total account diminished from 8.70 x 10{sup 7} UFC/ml to 550 UFC/ml, the presence of B

Determination of Residual Chlorine and Turbidity in Drinking Water. Instructor's Manual.

Science.gov (United States)

Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

This instructor's guide presents analytical methods for residual chlorine and turbidity. Topics include sample handling, permissable concentration levels, substitution of residual chlorine for bacteriological work, public notification, and the required analytical techniques to determine residual chlorine and turbidity. This publication is intended…

Determination of Residual Chlorine and Turbidity in Drinking Water. Student Manual.

Science.gov (United States)

Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

This student's manual covers analytical methods for residual chlorine and turbidity. Topics include sample handling, permissable concentration levels, substitution of residual chlorine for bacteriological work, public notification, and the required analytical techniques to determine residual chlorine and turbidity. The publication is intended for…

Anions Analysis in Ground and Tap Waters by Sequential Chemical and CO2-Suppressed Ion Chromatography

Directory of Open Access Journals (Sweden)

Glen Andrew D. De Vera

2011-06-01

Full Text Available An ion chromatographic method using conductivity detection with sequential chemical and CO2 suppression was optimized for the simultaneous determination of fluoride, chloride, bromide, nitrate,phosphate and sulfate in ground and tap water. The separation was done using an anion exchange column with an eluent of 3.2 mM Na2CO3 and 3.2 mM NaHCO3 mixture. The method was linear in the concentration range of 5 to 300 μg/L with correlation coefficients greater than 0.99 for the six inorganic anions. The method was also shown to be applicable in trace anions analysis as given by the low method detection limits (MDL. The MDL was 1μg/L for both fluoride and chloride. Bromide, nitrate, phosphate and sulfate had MDLs of 7 μg/L, 10 μg/L, 9 μg/L and 2 μg/L, respectively. Good precision was obtained as shown in the relative standard deviation of 0.1 to 12% for peak area and 0.1 to 0.3% for retention time. The sensitivity of the method improved with the addition of CO2 suppressor to chemical suppression as shown in the lower background conductivity and detection limits. The recoveries of the anions spiked in water at 300 μg/L level ranged from 100 to 104%. The method was demonstrated to be sensitive, accurate and precise for trace analysis of the six anions and was applied in the anions analysis in ground and tap waters in Malolos, Bulacan. The water samples were found to contain high concentrations of chloride of up to 476 mg/L followed by sulfate (38 mg/L, bromide (1 mg/L, phosphate (0.4 mg/L, fluoride (0.2 mg/L and nitrate (0.1 mg/L.

Remediation of water pollution caused by pharmaceutical residues based on electrochemical separation and degradation technologies: a review.

Science.gov (United States)

Sirés, Ignasi; Brillas, Enric

2012-04-01

In the last years, the decontamination and disinfection of waters by means of direct or integrated electrochemical processes are being considered as a very appealing alternative due to the significant improvement of the electrode materials and the coupling with low-cost renewable energy sources. Many electrochemical technologies are currently available for the remediation of waters contaminated by refractory organic pollutants such as pharmaceutical micropollutants, whose presence in the environment has become a matter of major concern. Recent reviews have focused on the removal of pharmaceutical residues upon the application of other important methods like ozonation and advanced oxidation processes. Here, we present an overview on the electrochemical methods devised for the treatment of pharmaceutical residues from both, synthetic solutions and real pharmaceutical wastewaters. Electrochemical separation technologies such as membrane technologies, electrocoagulation and internal micro-electrolysis, which only isolate the pollutants from water, are firstly introduced. The fundamentals and experimental set-ups involved in technologies that allow the degradation of pharmaceuticals, like anodic oxidation, electro-oxidation with active chlorine, electro-Fenton, photoelectro-Fenton and photoelectrocatalysis among others, are further discussed. Progress on the promising solar photoelectro-Fenton process devised and further developed in our laboratory is especially highlighted and documented. The abatement of total organic carbon or reduction of chemical oxygen demand from contaminated waters allows the comparison between the different methods and materials. The routes for the degradation of the some pharmaceuticals are also presented. Copyright © 2011 Elsevier Ltd. All rights reserved.

Status of persistent organic pesticide residues in water and food and their effects on environment and farmers: a comprehensive review in Nigeria

Directory of Open Access Journals (Sweden)

Norida Mazlan

2017-08-01

Full Text Available Pesticide helps to enhance agricultural production, however, it significantly affect both socio and environmental entities of a country. In Nigeria, pesticide is widely used, thus its traces have been detected in water, soil and air. Several studies have already indicated that most of the environmental ecology (air, water, and soil in Nigeria has been contaminated by persistent organic pesticides like organochlorine and organophosphate. Other reasons of high pesticide residues present in Nigeria environment is due to inappropriate dosage applied of pesticides that leaves behind excess. However, its residues are found above safety levels in the air, water, and soil across the nation. Based on previous analysis, it is indicated that 125,000-130,000 metric ton pesticides are being applied annually in Nigeria. Despite banned of some pesticides such as dichlorodiphenyltrichloroethane- and -Hexachlorocyclohexane, they are still being used by farmers in their agricultural production. Many of the Class 1 (high extremely toxic pesticides are still being used in developing countries like Nigeria. Hence, there is need to sensitize and educate the general public especially the end-users (farmers particularly on management practices of pesticides. Considering these entire hazardous situations, in this article the history of pesticide used in Nigeria has been reviewed in detail. The article also discussed the effects of pesticide use in Nigerian waters, soil and on crops. The risk of residual pesticide on agricultural workers, pesticide residue risk preventive measures by the Federal Government of Nigeria, banned and restricted pesticides in Nigeria, Nigerian Government and its efforts to eliminate persistent organic pesticides in use are also reviewed in details.

Removal of Cu (II and Zn (II from water with natural adsorbents from cassava agroindustry residues

Directory of Open Access Journals (Sweden)

Daniel Schwantes

2015-07-01

Full Text Available Current study employs solid residues from the processing industry of the cassava (Manihot esculenta Crantz (bark, bagasse and bark + bagasse as natural adsorbents for the removal of metal ions Cu(II and Zn(II from contaminated water. The first stage comprised surface morphological characterization (SEM, determination of functional groups (IR, point of zero charge and the composition of naturally existent minerals in the biomass. Further, tests were carried out to evaluate the sorption process by kinetic, equilibrium and thermodynamic studies. The adsorbents showed a surface with favorable adsorption characteristics, with adsorption sites possibly derived from lignin, cellulose and hemicellulose. The dynamic equilibrium time for adsorption was 60 min. Results followed pseudo-second-order, Langmuir and Dubinin-Radushkevich models, suggesting a chemisorption monolayer. The thermodynamic parameters suggested that the biosorption process of Cu and Zn was endothermic, spontaneous or independent according to conditions. Results showed that the studied materials were potential biosorbents in the decontamination of water contaminated by Cu(II and Zn(II. Thus, the above practice complements the final stages of the cassava production chain of cassava, with a new disposal of solid residues from the cassava agroindustry activity.

Laboratory studies of the properties of in-situ burn residues: chemical composition of residues

International Nuclear Information System (INIS)

Trudel, B.K.; Buist, I.A.; Schatzke, D.; Aurand, D.

1996-01-01

The chemical composition of the residue from small-scale burns of thick oil slicks was studied. The objective was to describe the changes in chemical composition in oils burning on water and to determine how these changes were influenced by the condition of the burn. Small-scale test burns involved burning 40-cm diameter pools of oil on water. A range of eight oil types including seven crude oils and an automotive diesel were burned. For each oil, slicks of fresh oil of three different thicknesses were tested. Two of the oils were tested before and after weathering. Results showed that the composition of the residue differed greatly from the parent oil. Asphaltenes, high-boiling-point aromatics and resins remained concentrated in the burn residue. The burning of slicks appeared to remove most of the lower-molecular weight aromatic hydrocarbons which included the more toxic and more bioavailable components of the crude oils. 11 refs., 6 tabs

Effects of slightly acidic electrolysed drinking water on mice.

Science.gov (United States)

Inagaki, Hideaki; Shibata, Yoshiko; Obata, Takahiro; Kawagoe, Masami; Ikeda, Katsuhisa; Sato, Masayoshi; Toida, Kazumi; Kushima, Hidemi; Matsuda, Yukihisa

2011-10-01

Slightly acidic electrolysed (SAE) water is a sanitizer with strong bactericidal activity due to hypochlorous acid. We assessed the safety of SAE water as drinking water for mice at a 5 ppm total residual chlorine (TRC) concentration to examine the possibility of SAE water as a labour- and energy-saving alternative to sterile water. We provided SAE water or sterile water to mice for 12 weeks, during which time we recorded changes in body weight and weekly water and food intakes. At the end of the experiment, all of the subject animals were sacrificed to assess serum aspartate aminotransferase, alanine aminotransferase and creatinine levels and to examine the main organs histopathologically under a light microscope. In addition, we investigated the bacteria levels of both types of water. We found no difference in functional and morphological health condition indices between the groups. Compared with sterile water, SAE water had a relatively higher ability to suppress bacterial growth. We suggest that SAE water at 5 ppm TRC is a safe and useful alternative to sterile water for use as drinking water in laboratory animal facilities.

Sulphate Removal from Water by Carbon Residue from Biomass Gasification: Effect of Chemical Modification Methods on Sulphate Removal Efficiency

Directory of Open Access Journals (Sweden)

Hanna Runtti

2016-02-01

Full Text Available Sulphate removal from mine water is a problem because traditional chemical precipitation does not remove all sulphates. In addition, it creates lime sediment as a secondary waste. Therefore, an inexpensive and environmental-friendly sulphate removal method is needed in addition to precipitation. In this study, carbon residues from a wood gasification process were repurposed as precursors to a suitable sorbent for SO42- ion removal. The raw material was modified using ZnCl2, BaCl2, CaCl2, FeCl3, or FeCl2. Carbon residues modified with FeCl3 were selected for further consideration because the removal efficiency toward sulphate was the highest. Batch sorption experiments were performed to evaluate the effects of the initial pH, initial SO42- ion concentration, and contact time on sulphate removal. The removal of SO42- ions using Fe-modified carbon residue was notably higher compared with unmodified carbon residue and commercially available activated carbon. The sorption data exhibited pseudo-second-order kinetics. The isotherm analysis indicated that the sorption data of Fe-modified carbon residues can be represented by the bi-Langmuir isotherm model.

Phosphorus Sorption Characteristics in Aluminum-based Water Treatment Residuals Reacted with Dairy Wastewater: 1. Isotherms, XRD, and SEM-EDS Analysis.

Science.gov (United States)

Zohar, Iris; Massey, Michael S; Ippolito, James A; Litaor, M Iggy

2018-05-01

We examined P sorption characteristics in Al-based water treatment residuals (Al-WTR) generated from slightly alkaline surface water and in an organic residual composite (WW-Al/O-WTR), produced by using the Al-WTR to treat organic-rich and high P concentration dairy wastewater. Solids from both residuals were examined using scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD), and exposed to P additions of 0 to 4000 mg L in a sorption experiment. The Al-WTR removed ∼97% of the added P, whereas WW-Al/O-WTR removed only 78% of the added P in the addition range of 0 to 100 mg P L. With P additions of ≥100 mg L, the removal rate declined to XRD indicated that the major mineral was calcite, with some silica and poorly crystalline Al hydroxides. Analysis by SEM-EDS, which used three-element overlay maps of the residual surfaces, indicated that P was sparsely sorbed on both calcic and Al (hydr)oxide surfaces, along with a few clusters, even at low P concentrations of the treated waters. Ternary clusters of P, Al, and Ca were more abundant on the WW-Al/O-WTR. Carbon distribution suggested that organic substances covered Al surfaces. Sorption of P onto WW-Al/O-WTR may be reversible due to relatively weak Ca-P and Al-P bonds induced by the slight alkaline nature and in the presence of organic moieties, enhancing the WW-Al/O-WTR potential to act as a P source, rather than a P sink, in agricultural applications. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Developments in hydroconversion processes for residues

Energy Technology Data Exchange (ETDEWEB)

Douwes, C T [Shell Res. B.V.; Wijffels, J B; Van Klinken, J; Van Zijll Langhout, W C

1979-01-01

A review of recent developments in hydrotreating processes for demetallization, desulfurization, and conversion to distillate products of residues covers catalyst developments for suppression of coke formation, maximum metals tolerance, and conversion selectivity; the effects of hydrogen pressure and temperature on catalyst deactivation and conversion; basic operating characteristics of conventional fixed-bed trickle-flow reactors, and of onstream catalyst replacement reactors, including the expanded-bed and the moving-bed reactor; a comparison of catalyst bed activity level, dirt tolerance, reactor effectiveness, temperature control, and thermal stability of the expanded-bed and moving-bed reactors; residue upgrading in slurry-bed reactors of dispersed vanadium sulfide catalyst in the oil; design and control features for safety and reliability; and a cost comparison between the indirect hydrotreating route, in which the asphalt fraction is separated prior to hydrotreating, and the as yet incompletely developed direct route.

Are tyrosine residues involved in the photoconversion of the water-soluble chlorophyll-binding protein of Chenopodium album?

Science.gov (United States)

Takahashi, S; Seki, Y; Uchida, A; Nakayama, K; Satoh, H

2015-05-01

Non-photosynthetic and hydrophilic chlorophyll (Chl) proteins, called water-soluble Chl-binding proteins (WSCPs), are distributed in various species of Chenopodiaceae, Amaranthaceae, Polygonaceae and Brassicaceae. Based on their photoconvertibility, WSCPs are categorised into two classes: Class I (photoconvertible) and Class II (non-photoconvertible). Chenopodium album WSCP (CaWSCP; Class I) is able to convert the chlorin skeleton of Chl a into a bacteriochlorin-like skeleton under light in the presence of molecular oxygen. Potassium iodide (KI) is a strong inhibitor of the photoconversion. Because KI attacks tyrosine residues in proteins, tyrosine residues in CaWSCP are considered to be important amino acid residues for the photoconversion. Recently, we identified the gene encoding CaWSCP and found that the mature region of CaWSCP contained four tyrosine residues: Tyr13, Tyr14, Tyr87 and Tyr134. To gain insight into the effect of the tyrosine residues on the photoconversion, we constructed 15 mutant proteins (Y13A, Y14A, Y87A, Y134A, Y13-14A, Y13-87A, Y13-134A, Y14-87A, Y14-134A, Y87-134A, Y13-14-87A, Y13-14-134A, Y13-87-134A, Y14-87-134A and Y13-14-87-134A) using site-directed mutagenesis. Amazingly, all the mutant proteins retained not only chlorophyll-binding activity, but also photoconvertibility. Furthermore, we found that KI strongly inhibited the photoconversion of Y13-14-87-134A. These findings indicated that the four tyrosine residues are not essential for the photoconversion. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

Vent clearing during a simulated loss-of-coolant accident in Mark I boiling-water-reactor pressure-suppression system

International Nuclear Information System (INIS)

Pitts, J.H.; McCauley, E.W.

1978-01-01

The response of the pressure-suspension containment system of Mark I boiling-water reactors to a loss-of-coolant accident (LOCA) is being studied. This response is a design basis for light-water nuclear reactors. Part of the study is being carried out on a 1 / 5 -scale experimental facility that models the pressure-suppression containment system of the Peach Bottom 2 nuclear power plant. The test series reported here focused on the initial or air-clearing phase of a hypothetical LOCA. Measured forces, measured pressures, and the hydrodynamic phenomena (observed with high-speed cameras) show a logical interrelationship

Static and Dynamic Water Motion-Induced Instability in Oxide Thin-Film Transistors and Its Suppression by Using Low-k Fluoropolymer Passivation.

Science.gov (United States)

Choi, Seungbeom; Jo, Jeong-Wan; Kim, Jaeyoung; Song, Seungho; Kim, Jaekyun; Park, Sung Kyu; Kim, Yong-Hoon

2017-08-09

Here, we report static and dynamic water motion-induced instability in indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) and its effective suppression with the use of a simple, solution-processed low-k (ε ∼ 1.9) fluoroplastic resin (FPR) passivation layer. The liquid-contact electrification effect, in which an undesirable drain current modulation is induced by a dynamic motion of a charged liquid such as water, can cause a significant instability in IGZO TFTs. It was found that by adopting a thin (∼44 nm) FPR passivation layer for IGZO TFTs, the current modulation induced by the water-contact electrification was greatly reduced in both off- and on-states of the device. In addition, the FPR-passivated IGZO TFTs exhibited an excellent stability to static water exposure (a threshold voltage shift of +0.8 V upon 3600 s of water soaking), which is attributed to the hydrophobicity of the FPR passivation layer. Here, we discuss the origin of the current instability caused by the liquid-contact electrification as well as various static and dynamic stability tests for IGZO TFTs. On the basis of our findings, we believe that the use of a thin, solution-processed FPR passivation layer is effective in suppressing the static and dynamic water motion-induced instabilities, which may enable the realization of high-performance and environment-stable oxide TFTs for emerging wearable and skin-like electronics.

Seasonal and spatial variations of glyphosate residues in surface waters of El Crespo stream, Buenos Aires province, Argentina.

Science.gov (United States)

Perez, Debora; Okada, Elena; Aparicio, Virginia; Menone, Mirta; Costa, Jose Luis

2017-04-01

El Crespo stream is located inside a small watershed (52,000 Ha) which is only influenced by farming activities without urban or industrial impact. The watershed can be divided in two areas, the southern area (upstream), mainly composed of intensive crops and the northern area (downstream) used only for extensive livestock. In this sense, "El Crespo" stream in an optimal site for monitoring screening of pesticide residues. The objective of this work was to determine the seasonal and spatial variations of glyphosate (GLY), in surface waters of "El Crespo" stream. We hypothesized that in surface waters of "El Crespo" stream the levels of GLY vary depending of the season and rainfall events. The water sampling was carried out from October to June (2014-2015) in two sites: upstream (US) and downstream (DS), before and after rain events. The water samples were collected by triplicate in 1 L polypropylene bottles and stored at -20°C until analysis. GLY was extracted from unfiltered water samples with a buffer solution (100 mM Na2B4O7•10H2O/100 mM K3PO4, pH=9) and derivatized with 9-fluorenylmethylchloroformate (1 mg/mL in acetonitrile). Afterwards samples were analyzed using liquid chromatography coupled to a tandem mass spectrometer (UPLC-MS/MS). The detection limit (LD) was 0.1 μg/L and the quantification limit (QL) was 0.5 μg/L. The rainfall regime was obtained from the database of INTA Balcarce. GLY was detected in 92.3% of the analyzed samples. In the US site, were GLY is regularly applied, the highest GLY concentration was registered in October (2.15 ± 0.16 μg/L); from November to June, the GLY levels decreased from 1.97 ± 0.17 μg/L to rain falls. On the rest of the months, the rainfall events were scarce and the GLY concentrations decreased in both. These results indicated that in the El Crespo stream the GLY residues vary according the applications in the field and the rainfall regime and the DS site is probably a sump of GLY residues applied upstream in

Residues leaching from 'Factory of barren ores'

International Nuclear Information System (INIS)

Rakhmatov, N.; Khakimov, N.; Nazarov, Kh.M.; Barotov, A.M.

2012-01-01

The objective of the present work is safe management of residues from Factory of Barren Ores, their reprocessing, expenditures reduction for remediation of Istiklol city former uranium tailings. For this purpose, some experiences were adopted - Factory of Barren Ores tailing use for filling up the open pit where water with uranium content 3-5 mg/l is located. Factory of Barren Ores waste are passed through heap leaching and have some amount of uranium salts dissolved in water. Thus, we propose to dissolve uranium from Factory of Barren Ores wastes with uranium bearing water flowing out from gallery and filling up the open-pit by radioactive wastes. In so doing, uranium content flowing out from gallery will increase twice, and further, passing them through apricot's shell, as a sorbent, we will clean the water against radionuclides. Residue samples with uranium content 0,015% from Factory of Barren Ores and uranium bearing waters from gallery 1 with uranium content 0,0025 g/l were used for laboratory tests. After which, a slurry was prepared by means of residue mixing with water in ratio of solid and liquid phases (S:L) - 1:2 and 9,7 ml of sulfuric acid (Ρ=1,82) was added which corresponds consumption by H 2 SO 4 176,54 kg/t. For the first test, leaching was carried out during 4 hours at ph=1,6 at room temperature. For the second test, leaching was carried out at 60 d eg C a nd ph=1,6 during 4 hours. Slurry heating and mixing was carried out by means of magnetic mixer. The basic residue leaching indicators are provided in this article.

Aluminum-based water treatment residual use in a constructed wetland for capturing urban runoff phosphorus: Column study

Science.gov (United States)

Aluminum-based water treatment residuals (Al-WTR) have a strong affinity to sorb phosphorus. In a proof-of-concept greenhouse column study, Al-WTR was surface-applied at 0, 62, 124, and 248 Mg/ha to 15 cm of soil on top of 46 cm of sand; Al-WTR rates were estimated to capture 0, 10, 20, and 40 year...

Bioenergy from sisal residues

Energy Technology Data Exchange (ETDEWEB)

Jungersen, G. [Dansk Teknologisk Inst. (Denmark); Kivaisi, A.; Rubindamayugi, M. [Univ. of Dar es Salaam (Tanzania, United Republic of)

1998-05-01

The main objectives of this report are: To analyse the bioenergy potential of the Tanzanian agro-industries, with special emphasis on the Sisal industry, the largest producer of agro-industrial residues in Tanzania; and to upgrade the human capacity and research potential of the Applied Microbiology Unit at the University of Dar es Salaam, in order to ensure a scientific and technological support for future operation and implementation of biogas facilities and anaerobic water treatment systems. The experimental work on sisal residues contains the following issues: Optimal reactor set-up and performance; Pre-treatment methods for treatment of fibre fraction in order to increase the methane yield; Evaluation of the requirement for nutrient addition; Evaluation of the potential for bioethanol production from sisal bulbs. The processing of sisal leaves into dry fibres (decortication) has traditionally been done by the wet processing method, which consumes considerable quantities of water and produces large quantities of waste water. The Tanzania Sisal Authority (TSA) is now developing a dry decortication method, which consumes less water and produces a waste product with 12-15% TS, which is feasible for treatment in CSTR systems (Continously Stirred Tank Reactors). (EG)

[Monitoring of the residue of fosthiazate in water samples using solid-phase extraction coupled with gas chromatography/mass spectrometry].

Science.gov (United States)

Zhu, Jing; Zhou, Xin; Fu, Chunmei; Liu, Sankang; Li, Zhangwan

2004-11-01

Solid-phase extraction (SPE) coupled with gas chromatography/mass spectrometry (GC/MS) was used to determine the fosthiazate residue in water samples. The water samples were first filtered through cellulose filters (0.45 microm pore size). A 100 mL volume of filtered water, in which 1 mL of methanol has been added, was then passed through a pre-conditioned 3 cm C18 cartridge at a flow-rate of 1.5 mL/min. Elution was performed by 1 mL of methanol. The eluant was finally dried under reduced pressure for solvent evaporation. The volume was quantitatively adjusted to 0.5 mL with methanol. The analysis was carried out on GC/MS. The mass spectrometer was operated in selected ion monitoring (SIM) mode. According to mass spectrum of fosthiazate, three selected ions at m/z of 126, 195, 283, respectively, were monitored for identification and quantification. High sensitivity and selectivity were achieved by using this method. The limit of detection for fosthiazate in water samples was determined to be 56.4 ng/L. The linearity was demonstrated over a wide range of concentrations covering from 0.282 to 141 microg/L. The recoveries were more than 85.5% and the relative standard deviations for the overall procedure were less than 4.42%. The fosthiazate residue was detected in the water samples from a pool near cropland where fosthiazate was used. The results demonstrate the suitability of the SPE-GC/MS approach for the analysis of fosthiazate in water.

Inhibiting TGFβ1 has a protective effect on mouse bone marrow suppression following ionizing radiation exposure in vitro

International Nuclear Information System (INIS)

Zhang Heng; Yan Hao; Wang Xinzhuo; Niu Jingxiu; Wang Hui; Wang Yingai; Meng Aimin; Li Jin

2013-01-01

Ionizing radiation (IR) causes not only acute tissue damage but also residual bone marrow (BM) suppression. The induction of residual BM injury is primarily attributable to the induction of reactive oxygen species (ROS) pressure in hematopoietic cells. In this study, we examined if SB431542, a transforming growth factor β1 (TGFβ1) inhibitor, can mitigate IR-induced BM suppression in vitro. Our results showed that treatment with SB431542 protected mice bone marrow mononuclear cells (BMMNCs), hematopoietic progenitor cells (HPCs) and hematopoietic stem cells (HSCs) from IR-induced suppression using cell viability assays, clonogenic assays and competitive repopulation assays. Moreover, expression of gene-related ROS production in hematopoietic cells was analyzed. The expression of NADPH oxidative 1 (NOX1), NOX2 and NOX4 was increased in irradiated BMMNCs, and that of NOX2 and NOX4 was reduced by SB431542 treatment. Therefore, the results from this study suggest that SB431542, a TGFβ1 inhibitor, alleviates IR-induced BM suppression at least in part via inhibiting IR-induced NOX2 and NOX4 expression. (author)

Viimsi water treatment plant for Ra removal: NORM residue/waste generation, radiation safety issues, and regulatory response

Energy Technology Data Exchange (ETDEWEB)

Kiisk, M.; Suursoo, S.; Realo, E.; Jantsikene, A.; Lumiste, L.; Vaeaer, K.; Isakar, K.; Koch, R. [University of Tartu (Estonia)

2014-07-01

In early 2012, the first large-scale water treatment plant, specifically designed to remove Ra-isotopes from groundwater, was commissioned in Viimsi parish, North-Estonia. The plant serves approximately 15 000 consumers with maximum production capacity of 6000 m{sup 3}/d. The chosen water treatment technology is chemical free and is based on co-precipitation and adsorption with Fe(OH){sub 3} and MnO{sub 2} flocks, and adsorption of residual Ra onto zeolite sand. The chosen technology is a complex approach and is designed to reduce high Fe and Mn concentrations as well as dissolved gases along with Ra isotopes. It is proved to be well adapted with hydro-chemical conditions of the groundwater feeding the plant. As the novel technology has been applied for the first time on a large scale, the plant was taken under long-term investigation when commissioned. The latter focuses on three areas: Ra removal efficiency and its dynamics, build-up of radioactive waste, and radiation safety. The average Ra-226 and Ra-228 activity concentrations in raw water feeding the plant are approximately 0.5 Bq/L and 0.6 Bq/L, respectively, resulting in total indicative dose of 0.4 mSv/y. Operating conditions of the plant are restricted by the established indicative value of 0.1 mSv/y for drinking water, i.e. a minimum 75% removal efficiency for Ra is required. Results of the studies show that the plant operates at Ra-removal efficiency of 98% or higher without the need of regeneration or replacement of filtering materials within the first two years. Measurements confirm that ∼90% of Ra accumulates in the solid filter media, 8-9% is washed out by backwash system as liquid effluent and 1-2% is fed on to the consumer distribution network. It has been calculated that at the level of current production capacity (below 3000 m{sup 3}/d) the yearly accumulation rate in the plant is approximately 300 and 400 MBq/y for Ra-226 and Ra-228, respectively. These values strongly exceed the exemption

Variable Suppression of Serum Thyroxine in Female Mice of Different Inbred Strains by Triiodothyronine Administered in Drinking Water

Science.gov (United States)

Hamidi, Sepehr; Aliesky, Holly; Chen, Chun-Rong; Rapoport, Basil

2010-01-01

Background Recombinant-inbred mouse strains differ in their susceptibility to Graves'-like hyperthyroidism induced by immunization with adenovirus expressing the human thyrotropin (TSH) receptor. Because one genetic component contributing to this susceptibility is altered thyroid sensitivity to TSH receptor agonist stimulation, we wished to quantify thyroid responsiveness to TSH. For such studies, it is necessary to suppress endogenous TSH by administering L-3,5,3′-triiodothyronine (L-T3), with the subsequent decrease in serum thyroxine (T4) reflecting endogenous TSH suppression. Our two objectives were to assess in different inbred strains of mice (i) the extent of serum T4 suppression after L-T3 administration and (ii) the magnitude of serum T4 increase induced by TSH. Methods Mice were tail-bled to establish baseline-serum T4 before L-T3 administration. We initially employed a protocol of L-T3-supplemented drinking water for 7 days. In subsequent experiments, we injected L-T3 intraperitoneally (i.p.) daily for 3 days. Mice were then injected i.p. with bovine TSH (10 mU) and euthanized 5 hours later. Serum T4 was assayed before L-T3 administration, and before and after TSH injection. In some experiments, serum T3 and estradiol were measured in pooled sera. Results Oral L-T3 (3 or 5 μg/mL) suppressed serum T4 levels by 26%–64% in female BALB/c mice but >95% in males. T4 suppression in female B6 mice ranged from 0% to 90%. In C3H mice, L-T3 at 3 μg/mL was ineffective but 5 μg/mL achieved >80% serum T4 reduction. Unlike inbred mice, in outbred CF1 mice the same protocol was more effective: 83% in females and 100% suppression in males. The degree of T4 suppression was unrelated to baseline T4, T3, or estradiol, but was related to mouse weight and postmortem T3, with greater suppression in larger mice (outbred CF1 animals and inbred males). Among females with serum T4 suppression >80%, the increase in serum T4 after TSH injection was greater for BALB

Isolation of Bacillus subtilis as indicator in the disinfection of residual water by means of gamma radiation

International Nuclear Information System (INIS)

Mata J, M.; Colin C, A.; Lopez V, H.; Brena V, M.; Carrasco A, H.; Pavon R, S.

2002-01-01

In the attempt to get more alternatives of disinfection of residual water, the Bacillus subtilis was isolated by means of gamma radiation as a bio indicator of disinfection since it turned out to be resistant to the 5 KGy dose, comparing this one with other usual microorganisms as biondicators like E. coli and S typhimurium which turn out more sensitive to such dose. (Author)

Antimicrobial residues in animal waste and water resources proximal to large-scale swine and poultry feeding operations

Science.gov (United States)

Campagnolo, E.R.; Johnson, K.R.; Karpati, A.; Rubin, C.S.; Kolpin, D.W.; Meyer, M.T.; Esteban, J. Emilio; Currier, R.W.; Smith, K.; Thu, K.M.; McGeehin, M.

2002-01-01

Expansion and intensification of large-scale animal feeding operations (AFOs) in the United States has resulted in concern about environmental contamination and its potential public health impacts. The objective of this investigation was to obtain background data on a broad profile of antimicrobial residues in animal wastes and surface water and groundwater proximal to large-scale swine and poultry operations. The samples were measured for antimicrobial compounds using both radioimmunoassay and liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) techniques. Multiple classes of antimicrobial compounds (commonly at concentrations of >100 μg/l) were detected in swine waste storage lagoons. In addition, multiple classes of antimicrobial compounds were detected in surface and groundwater samples collected proximal to the swine and poultry farms. This information indicates that animal waste used as fertilizer for crops may serve as a source of antimicrobial residues for the environment. Further research is required to determine if the levels of antimicrobials detected in this study are of consequence to human and/or environmental ecosystems. A comparison of the radioimmunoassay and LC/ESI-MS analytical methods documented that radioimmunoassay techniques were only appropriate for measuring residues in animal waste samples likely to contain high levels of antimicrobials. More sensitive LC/ESI-MS techniques are required in environmental samples, where low levels of antimicrobial residues are more likely.

Antimicrobial residues in animal waste and water resources proximal to large-scale swine and poultry feeding operations.

Science.gov (United States)

Campagnolo, Enzo R; Johnson, Kammy R; Karpati, Adam; Rubin, Carol S; Kolpin, Dana W; Meyer, Michael T; Esteban, J Emilio; Currier, Russell W; Smith, Kathleen; Thu, Kendall M; McGeehin, Michael

2002-11-01

Expansion and intensification of large-scale animal feeding operations (AFOs) in the United States has resulted in concern about environmental contamination and its potential public health impacts. The objective of this investigation was to obtain background data on a broad profile of antimicrobial residues in animal wastes and surface water and groundwater proximal to large-scale swine and poultry operations. The samples were measured for antimicrobial compounds using both radioimmunoassay and liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) techniques. Multiple classes of antimicrobial compounds (commonly at concentrations of > 100 microg/l) were detected in swine waste storage lagoons. In addition, multiple classes of antimicrobial compounds were detected in surface and groundwater samples collected proximal to the swine and poultry farms. This information indicates that animal waste used as fertilizer for crops may serve as a source of antimicrobial residues for the environment. Further research is required to determine if the levels of antimicrobials detected in this study are of consequence to human and/or environmental ecosystems. A comparison of the radioimmunoassay and LC/ESI-MS analytical methods documented that radioimmunoassay techniques were only appropriate for measuring residues in animal waste samples likely to contain high levels of antimicrobials. More sensitive LC/ESI-MS techniques are required in environmental samples, where low levels of antimicrobial residues are more likely.

A sensitive multi-residue method for the determination of 35 micropollutants including pharmaceuticals, iodinated contrast media and pesticides in water.

Science.gov (United States)

Valls-Cantenys, Carme; Scheurer, Marco; Iglesias, Mònica; Sacher, Frank; Brauch, Heinz-Jürgen; Salvadó, Victoria

2016-09-01

A sensitive, multi-residue method using solid-phase extraction followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to determine a representative group of 35 analytes, including corrosion inhibitors, pesticides and pharmaceuticals such as analgesic and anti-inflammatory drugs, five iodinated contrast media, β-blockers and some of their metabolites and transformation products in water samples. Few other methods are capable of determining such a broad range of contrast media together with other analytes. We studied the parameters affecting the extraction of the target analytes, including sorbent selection and extraction conditions, their chromatographic separation (mobile phase composition and column) and detection conditions using two ionisation sources: electrospray ionisation (ESI) and atmospheric pressure chemical ionisation (APCI). In order to correct matrix effects, a total of 20 surrogate/internal standards were used. ESI was found to have better sensitivity than APCI. Recoveries ranging from 79 to 134 % for tap water and 66 to 144 % for surface water were obtained. Intra-day precision, calculated as relative standard deviation, was below 34 % for tap water and below 21 % for surface water, groundwater and effluent wastewater. Method quantification limits (MQL) were in the low ng L(-1) range, except for the contrast agents iomeprol, amidotrizoic acid and iohexol (22, 25.5 and 17.9 ng L(-1), respectively). Finally, the method was applied to the analysis of 56 real water samples as part of the validation procedure. All of the compounds were detected in at least some of the water samples analysed. Graphical Abstract Multi-residue method for the determination of micropollutants including pharmaceuticals, iodinated contrast media and pesticides in waters by LC-MS/MS.

Cover crop residue effects on machine-induced soil compaction

OpenAIRE

Ess, Daniel R.

1994-01-01

Crop production systems which utilize the biomass produced by rye (Secale cereale ) to suppress weed growth and conserve soil moisture have been developed at Virginia Tech. The success of alternative, reduced-input crop production systems has encouraged research into the potential for breaking the traffic-tillage cycle associated with conventional tillage crop production systems. The fragile residues encountered in agricultural crop production, whether incorporated into the ...

Estimating survival rates of quagga mussel (Dreissena rostriformis bugensis veliger larvae under summer and autumn temperature regimes in residual water of trailered watercraft at Lake Mead, USA

Directory of Open Access Journals (Sweden)

Wook Jin Choi

2013-01-01

Full Text Available On 6 January 2007, invasive quagga mussels [Dreissena rostriformis bugensis (Andrusov, 1897] were discovered in the Boulder Basin ofLake Mead, Nevada, a popular site for recreational boating in the southwestern United States. Recreational watercraft are considered aprimary vector for overland dispersal of quagga mussel veliger larvae between water bodies. Thus, effective decontamination of veligers inresidual water carried by trailered recreation boats is critical to controlling this species’ spread. The survival rate of quagga mussel veligerswas measured during exposure to environmental temperature conditions mimicking those experienced in the residual water of traileredvessels during warm summer and cooler autumn months in the semi-arid southwestern United States. Under warm summer conditions,quagga mussel veligers survived approximately five days while under cooler autumn conditions they survived 27 days. When tested underautumn temperature conditions veliger survival times increased with increased level of larval development. The results suggested a greaterlikelihood of veliger transport in the residual water of trailered watercraft during autumn months. The results indicated that presentlyrecommended vessel quarantine times to kill all externally attached juvenile and adult dreissenid mussels prior to launching in an uninfested water body should be increased to generate 100% veliger mortality in residual water unable to be fully drained from the internal areas of watercraft.

Minimization of Residual Stress in an Al-Cu Alloy Forged Plate by Different Heat Treatments

Science.gov (United States)

Dong, Ya-Bo; Shao, Wen-Zhu; Jiang, Jian-Tang; Zhang, Bao-You; Zhen, Liang

2015-06-01

In order to improve the balance of mechanical properties and residual stress, various quenching and aging treatments were applied to Al-Cu alloy forged plate. Residual stresses determined by the x-ray diffraction method and slitting method were compared. The surface residual stress measured by x-ray diffraction method was consistent with that measured by slitting method. The residual stress distribution of samples quenched in water with different temperatures (20, 60, 80, and 100 °C) was measured, and the results showed that the boiling water quenching results in a 91.4% reduction in residual stress magnitudes compared with cold water quenching (20 °C), but the tensile properties of samples quenched in boiling water were unacceptably low. Quenching in 80 °C water results in 75% reduction of residual stress, and the reduction of yield strength is 12.7%. The residual stress and yield strength level are considerable for the dimensional stability of aluminum alloy. Quenching samples into 30% polyalkylene glycol quenchants produced 52.2% reduction in the maximum compressive residual stress, and the reduction in yield strength is 19.7%. Moreover, the effects of uphill quenching and thermal-cold cycling on the residual stress were also investigated. Uphill quenching and thermal-cold cycling produced approximately 25-40% reduction in residual stress, while the effect on tensile properties is quite slight.

Kefiran suppresses antigen-induced mast cell activation.

Science.gov (United States)

Furuno, Tadahide; Nakanishi, Mamoru

2012-01-01

Kefir is a traditional fermented milk beverage produced by kefir grains in the Caucasian countries. Kefiran produced by Lactobacillus kefiranofaciens in kefir grains is an exopolysaccharide having a repeating structure with glucose and galactose residues in the chain sequence and has been suggested to exert many health-promoting effects such as immunomodulatory, hypotensive, hypocholesterolemic activities. Here we investigated the effects of kefiran on mast cell activation induced by antigen. Pretreatment with kefiran significantly inhibited antigen-induced Ca(2+) mobilization, degranulation, and tumor necrosis factor-α production in bone marrow-derived mast cells (BMMCs) in a dose-dependent manner. The phosphorylation of Akt, glycogen synthase kinase 3β, and extracellular signal-regulated kinases (ERKs) after antigen stimulation was also suppressed by pretreatment of BMMCs with kefiran. These findings indicate that kefiran suppresses mast cell degranulation and cytokine production by inhibiting the Akt and ERKs pathways, suggesting an anti-inflammatory effect for kefiran.

Electrochemical oxidation of drug residues in water by the example of tetracycline, gentamicin and Aspirin {sup trademark}

Energy Technology Data Exchange (ETDEWEB)

Weichgrebe, D.; Danilova, E.; Rosenwinkel, K.H. [Inst. of Water Quality and Waste Management, Univ. of Hannover, Hannover (Germany); Vedenjapin, A.; Baturova, M. [Inst. of Organic Chemistry, Russian Academy of Science, Moscow (Russian Federation)

2003-07-01

The electrochemical oxidation as a method to destroy drug residues like Aspirin {sup trademark}, tetracycline or gentamicin in water was investigated with C-Anode (modified by manganese oxides) and Pt Anode. The mechanism of Aspirin {sup trademark} and tetracycline oxidation and the influence of the biocide effect was observed using GC-MS and three different microbiological tests. In general the biological availability increases with progressive oxidation of the antibiotics. (orig.)

Using residual tritiated water from Cernavoda NPP to study Danube - Black Sea Canal hydrodynamics

International Nuclear Information System (INIS)

Varlam, C.; Stefanescu, I.; Lazar, R.; Varlam, M.; Patrascu, V.; Bucur, C.; Bobric, E.

2003-01-01

By benefiting of Cernavoda NPP's location in the neighbourhood of Danube - Black Sea Canal one suggests extending the area of interest along this canal particularly to use the residual tritiated water from this CANDU type reactor as tracing means in the study of canal's hydrodynamics. This canal appears to be ideal for such a study because releases in normal operation of NPP are occasional. The tritiated water can be used for simulating the transport and dispersion of soluble pollutants because it has the same physical characteristics as the usual water. By measuring response curves produced at injecting a known amount of tracer one can developed an efficient method for estimating: the soluble pollutant velocity along the canal; attenuation rate of concentration peak as a function of time as well as the time required by the propagation front of the soluble pollutant to reach a given point along the canal. In this work the calculation of the mixture length as a function of the particular characteristics of the canal is presented as well as different experimental formulas. Also the reference level of tritium concentration in the investigated area is established for future experiments

Electroremediation of air pollution control residues in a continuous reactor

DEFF Research Database (Denmark)

Jensen, Pernille Erland; Ferreira, Célia M. D.; Hansen, Henrik K.

2010-01-01

Air pollution control (APC) residue from municipal solid waste incineration is considered hazardous waste due to its alkalinity and high content of salts and mobile heavy metals. Various solutions for the handling of APC-residue exist, however most commercial solutions involve landfilling. A demand...... were made with raw residue, water-washed residue, acid washed residue and acid-treated residue with emphasis on reduction of heavy metal mobility. Main results indicate that the reactor successfully removes toxic elements lead, copper, cadmium and zinc from the feed stream, suggesting...

Mark I 1/5-scale boiling water reactor pressure suppression experiment. Quick-look report for test numbers 1.0(a) and 1.0(b) performed on March 4 and 8, 1977

International Nuclear Information System (INIS)

McCauley, E.W.; Pitts, J.H.

1977-01-01

The experimental results obtained from pressure suppression experiment numbers 1.0(a) and 1.0(b) that were performed on the Lawrence Livermore Laboratory's 1 / 5 -scale boiling water reactor (BWR) Mark I pressure suppression experimental facility are summarized

Evaluation of a treatment system type septic tank - filter anaerobic of upward flow for the residual waters of the ecological benefit of the coffee

International Nuclear Information System (INIS)

Sanchez C, Jose Alejandro

1997-01-01

Colombia is the first country in the production of soft coffee in the world. The benefit for humid way it makes that this quality of coffee is obtained; however, the high consumption of water in the process and the later discharge to the superficial or underground sources, they have generated an environmental problem of great magnitude. Also, the sources of water that they have been contaminated with the discharges of the liquid waste that come from benefit of coffee they present, among other, serious inconveniences to be used as supplying sources of drinkable water. In time of crop, the coffee areas and their superficial sources of water usually register high indexes of contamination like consequence of the discharges of residual waters that come from the benefit of the coffee. In the Departments of Quindio, Valle, Caldas, Antioquia, etc., they have been come executing investigations of the residuals treatment that are derived of the pulp removal of the coffee (via humid), for anaerobic methods with satisfactory results. This project had the collaboration of the Departmental Committee of Coffee of Antioquia and the Environmental Engineering of the Antioquia University and it is formulated toward the evaluation of a Anaerobic filter of Ascendant flow, FAFA, preceded of a septic tank (biological sedimentation), as a treatment system of the coffee residual waters, with a waste native of a ecological benefit area. The obtained results were satisfactory although the generated waste is very intermittent and in times that are not of coffee crop it doesn't take place; what hinders more the application of biological systems for its treatment

comparative assessment residual soils in residual soils in parts of e

African Journals Online (AJOL)

eobe

residual soil formed from Zuma rock. The Zuma r is an igneous .... The liquid limit (LL) is the lowest water content above which soil .... where this effect begins to be counteracted by the saturation of the ... retaining walls, tunnel linings and timbering of excavation. .... event of pore pressure build up due to excessive moisture.

An infrared scattering by evaporating droplets at the initial stage of a pool fire suppression by water sprays

Science.gov (United States)

Dombrovsky, Leonid A.; Dembele, Siaka; Wen, Jennifer X.

2018-06-01

The computational analysis of downward motion and evaporation of water droplets used to suppress a typical transient pool fire shows local regions of a high volume fraction of relatively small droplets. These droplets are comparable in size with the infrared wavelength in the range of intense flame radiation. The estimated scattering of the radiation by these droplets is considerable throughout the entire spectrum except for a narrow region in the vicinity of the main absorption peak of water where the anomalous refraction takes place. The calculations of infrared radiation field in the model pool fire indicate the strong effect of scattering which can be observed experimentally to validate the fire computational model.

Impacts of climate-induced changes on the distribution of pesticides residues in water and sediment of Lake Naivasha, Kenya.

Science.gov (United States)

Otieno, Peter O; Owuor, P Okinda; Lalah, Joseph O; Pfister, Gerd; Schramm, Karl-Werner

2013-03-01

This study reports evidence of increased chlorpyrifos contamination in sediment and water in Lake Naivasha following its intensive application in the horticultural farms in the catchment area. Analytical results show that levels of chlorpyrifos residues were influenced by climate-induced rainfall pattern with higher levels reported during period of heavy precipitation with significant decrease during low rainfall. On average, the levels ranged between 14.8 and 32.8 ng g(-1) in sediment during rainy season compared to a range of 8.5-16.6 ng g(-1) in the dry season. Additionally, the mean concentration of chlorpyrifos in water ranged between 8.61 and 22.4 μg L(-1) during rainy season and below detection limit (bdl) -13.6 μg L(-1) in dry season as quantified by enzyme-linked immunosorbent assay. Meanwhile, independent t test analysis indicated that there was significant difference in concentration at p ≤ 0.05 between the seasons with respect to sediment and water samples. This demonstrated that climate-induced variations had considerable influence on contamination. While diazinon and carbofuran were equally applied intensively, their levels were below the detection limit in the all the samples analyzed. ELISA results were validated by the capillary-HPLC photodiode-array detector instrument analysis, and statistical comparison showed no significant difference between them. It was evident that chlorpyrifos residues determination in water and sediment by ELISA can be a useful strategy in environmental management and monitoring program, and a complimentary analytical tool to high performance liquid chromatography. Levels of chlorpyrifos detected in sediment and water were found to exceed recommended criteria for protection of aquatic life and preservation of water quality and may be hazardous if not regularly monitored.

Carbon Nanotubes Facilitate Oxidation of Cysteine Residues of Proteins.

Science.gov (United States)

Hirano, Atsushi; Kameda, Tomoshi; Wada, Momoyo; Tanaka, Takeshi; Kataura, Hiromichi

2017-10-19

The adsorption of proteins onto nanoparticles such as carbon nanotubes (CNTs) governs the early stages of nanoparticle uptake into biological systems. Previous studies regarding these adsorption processes have primarily focused on the physical interactions between proteins and nanoparticles. In this study, using reduced lysozyme and intact human serum albumin in aqueous solutions, we demonstrated that CNTs interact chemically with proteins. The CNTs induce the oxidation of cysteine residues of the proteins, which is accounted for by charge transfer from the sulfhydryl groups of the cysteine residues to the CNTs. The redox reaction simultaneously suppresses the intermolecular association of proteins via disulfide bonds. These results suggest that CNTs can affect the folding and oxidation degree of proteins in biological systems such as blood and cytosol.

Measurement of conformational constraints in an elastin-mimetic protein by residue-pair selected solid-state NMR

International Nuclear Information System (INIS)

Hong, Mei; McMillan, R. Andrew; Conticello, Vincent P.

2002-01-01

We introduce a solid-state NMR technique for selective detection of a residue pair in multiply labeled proteins to obtain site-specific structural constraints. The method exploits the frequency-offset dependence of cross polarization to achieve 13 CO i → 15 N i → 13 Cα i transfer between two residues. A 13 C, 15 N-labeled elastin mimetic protein (VPGVG) n is used to demonstrate the method. The technique selected the Gly3 Cα signal while suppressing the Gly5 Cα signal, and allowed the measurement of the Gly3 Cα chemical shift anisotropy to derive information on the protein conformation. This residue-pair selection technique should simplify the study of protein structure at specific residues

Pressure suppression pool thermal mixing

International Nuclear Information System (INIS)

Cook, D.H.

1984-01-01

A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing model is verified by comparing the model predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

Efficiency in the reduction of chromium by a wild bacterium in a Batch treatment type using residual water substrate from the municipality of Pasto, Colombia

Directory of Open Access Journals (Sweden)

Deisy Lorena Guerrero Ceballos

2017-05-01

Full Text Available Objective: To evaluate the efficiency in the reduction of chromium in a Batch treatment type, using municipal residual water substrate inoculated with a wild bacterium. Materials and methods: The reduction percentage of hexavalent chromium of three wild bacteria previously isolated from residual water from the Pasto River was verified at laboratory scale (Bacillus thuringiensis, Bacillus amyloliquefaciens and Paenibacillus sp.; the isolated that showed the highest percentage of reduction of Cr was selected and was subjected to different treatments. The analysis of results was done using descriptive statistics. Results: B. thuringiensis, B. amyloliquefaciens, and Paenibacillus sp., presented percentages of reduction of Cr (VI of 82,01%; 80,85% and 79,27%, respectively. It was determined that the third treatment (nonsterile water from the Pasto River with B. thuringiensis presented significant differences with regard to the other (p = 0.0001 α = 0.05, concluding that B. thuringiensis reduces in greater proportion the Cr (VI. The results found in this research are promising in the field of bioremediation of contaminated effluents with Chrome since they may be taken as the basis for implementing strategies of bioremediation on a large scale. Conclusion: The bacteria B. thuringiensis presented high efficiency in the reduction of hexavalent chromium (99.42% when implemented in a treatment at laboratory scale of residual nonsterile water.

Effect of Solution Properties on Arsenic Adsorption by Drinking Water Treatment Residuals

Science.gov (United States)

Nagar, R.; Sarkar, D.; Datta, R.; Sharma, S.

2005-05-01

Arsenic (As) is a ubiquitous element in the environment. Higher levels of As in soils may result from various anthropogenic sources such as use of arsenical pesticides, fertilizers, wood preservatives, smelter wastes, and coal combustion. This is of great environmental and human health concern due to the high toxicity and proven carcinogenicity of several arsenical species. Thus there is a need for developing cost effective technologies capable of lowering bioavailable As concentrations in soils to environmentally acceptable levels. In-situ immobilization of metals using inexpensive amendments such as minerals (apatite, zeolite, or clay minerals) or waste by-products (steel shot, beringite, and iron-rich biosolids) to reduce bioavailability is an inexpensive alternative to the more expensive ex-situ remediation methods. One such emerging in-situ technique is the application of drinking water treatment residuals (WTRs). WTRs can be classified as a byproduct of drinking water treatment plants and are generally composed of amorphous Fe/Al oxides, activated C and cationic polymers. WTRs possess amorphous structure and generally have high positive charge. Because As is chemically similar to phosphorus, the oxyanions As (V) and As (III) may have the potential of being retained by the WTRs. Thus, it is hypothesized that WTRs retain As irreversibly, thereby reducing As biavailability. As mobility of arsenic is controlled by adsorption reactions, knowledge of adsorption of As by WTRs is of primary relevance. Although the overall rate of adsorption is dependent on numerous factors, review of the literature indicates that competing ions in solution play an important role in the overall retention of As; however, little work has been conducted to identify which ions provide the most competition. As arsenic adsorption appears to be influenced by the variable pH-dependent charges developed on the soil particle surfaces, the effect of pH is also of critical importance. Hence, the

Development of a SERS aptasensor for detection of medical residues

DEFF Research Database (Denmark)

Frøhling, Kasper Bayer

Low levels of medical residues in environmental, industrial and domestic water systems is a growing concern. The biosensor industry is trying to accomodate the need of sensitive and specific sensor systems capable of ultra-low level detection of medical residues. In this PhD project a surface...... for sensitive and selective capture of medical residues....

Defense Response and Suppression of Phytophthora Blight Disease of Pepper by Water Extract from Spent Mushroom Substrate of Lentinula edodes

Directory of Open Access Journals (Sweden)

Dae-Sun Kang

2017-06-01

Full Text Available The spent mushroom substrate (SMS of Lentinula edodes that was derived from sawdust bag cultivation was used as materials for controlling Phytophthora blight disease of pepper. Water extract from SMS (WESMS of L. edodes inhibited mycelial growth of Phytophthora capsici, suppressed Phytophthora blight disease of pepper seedlings by 65% and promoted growth of the plant over 30%. In high performance liquid chromatography (HPLC analysis, oxalic acid was detected as the main organic acid compound in WESMS and inhibited the fungal mycelium at a minimum concentration of 200 mg/l. In quantitative real-time PCR, the transcriptional expression of CaBPR1 (PR protein 1, CaBGLU (β-1,3-glucanase, CaPR-4 (PR protein 4, and CaPR-10 (PR protein 10 were significantly enhanced on WESMS and DL-β-aminobutyric acid (BABA treated pepper leaves. In addition, the salicylic acid content was also increased 4 to 6 folds in the WESMS and BABA treated pepper leaves compared to water treated leaf sample. These findings suggest that WESMS of L. edodes suppress Phytophthora blight disease of pepper through multiple effects including antifungal activity, plant growth promotion, and defense gene induction.

Dichlorvos (DDVP residue removal from tomato by washing with tap and ozone water, a commercial detergent solution and ultrasonic cleaner

Directory of Open Access Journals (Sweden)

Ali HESHMATI

Full Text Available Abstract Dichlorvos (DDVP is one of the most consumption chlorinated organophosphate insecticide used on tomato. The knowledge about the influence of postharvest household processes on the levels of DDVP residues in vegetables is required to estimate dietary exposure. In this study, the removal of sprayed dichlorvos (DDVP on tomato by washing with tap, ozonated water (in dosages of 2, 4 and 6 mg ozone/L, a commercial detergent solution (in concentration of 1, 2 and 3% and ultrasonic cleaner (with power of 100, 200 and 300 W was investigated. DDVP residue was determined by gas chromatography with electron capture detector. Washing processes led to the significant reduction of DDVP. The gradual increase in the percentage of the removal was observed due to increment of washing time, ozone dosage, and concentration of detergent solution as well as ultrasonic power. The maximum removal percentage of DDVP after 15 min of washing with tap and ozonated water, a detergent solution and ultrasonic cleaner was 30.7, 91.9, 70.7, and 88.9%, respectively. In general, results indicated washing with tap, ozonated water, a detergent solution and ultrasonic cleaning are effective methods for removal of DDVP from tomato and reduction of its dietary exposure without influence on product quality.

Monitoring and removal of residual phthalate esters and pharmaceuticals in the drinking water of Kaohsiung City, Taiwan.

Science.gov (United States)

Yang, Gordon C C; Yen, Chia-Heng; Wang, Chih-Lung

2014-07-30

This study monitored the occurrence and removal efficiencies of 8 phthalate esters (PAEs) and 13 pharmaceuticals present in the drinking water of Kaohsiung City, Taiwan. The simultaneous electrocoagulation and electrofiltration (EC/EF) process was used to remove the contaminants. To this end, a monitoring program was conducted and a novel laboratory-prepared tubular carbon nanofiber/carbon/alumina composite membrane (TCCACM) was incorporated into the EC/EF treatment module (collectively designated as "TCCACM-EC/EF treatment module") to remove the abovementioned compounds from water samples. The monitoring results showed that the concentrations of PAEs were lower in water samples from drinking fountains as compared with tap water samples. No significant differences were found between the concentrations of pharmaceuticals in the two types of water samples. Under optimal operating conditions, the TCCACM-EC/EF treatment module yielded the lowest residual concentrations, ranging from not detected (ND) to 52ng/L for PAEs and pharmaceuticals of concern in the tap water samples. Moreover, the performance of the TCCACM-EC/EF treatment module is comparable with a series of treatment units employed for the drinking fountain water treatment system. The relevant removal mechanisms involved in the TCCACM-EC/EF treatment module were also discussed in this work. Copyright © 2014 Elsevier B.V. All rights reserved.

Forensic analysis of high explosives residues in post-blast water samples employing solid phase extraction for analyte pro-concentration

International Nuclear Information System (INIS)

Umi Kalsom Ahmad; Rajendran, Sumathy; Ling, Lee Woan

2008-01-01

Nitro aromatic, nitramine and nitrate ester compounds are a major group of high order explosive or better known as military explosives. Octahydro-1,3,5,7-tetrazocine (HMX), 1,3,5-hexahydro-1,3,5-trinitro triazine (RDX), 2,4,6-trinitro-toluene (TNT), pentaerythritol tetranitrate (PETN) and 2,4-dinitrotoluene (2,4-DNT) are secondary high explosives classified as most commonly used explosives components. There is an increasing demand for pre-concentration of these compounds in water samples as the sensitivity achieved by instrumental analytical methods for these high explosives residues are the main drawback in the application at trace levels for forensic analysis. Hence, a simple cartridge solid phase extraction (SPE) procedure was optimized as the off-line extraction and pre-concentration method to enhance the detection limit of high explosive residues using micellar electrokinetic chromatography (MEKC) and gas chromatography with electron-capture detection (GC-ECD) methods. The SPE cartridges utilized LiChrolut EN as the SPE adsorbent. By emplying pre-concentration using SPE, the detection limits of the target analytes in water sample were lowered by more than 1000 times with good percentage recovery (>87%) for MEKC method and lowered by 120 times with more than 2 % percentage recovery for GC-ECD methods. In order to test the feasibility of the developed method to real cases, post-blast water samples were analyzed. The post-blast water samples which were collected from Baling Bom training range, Ulu Kinta, Perak contained RDX and PETN in the range of 0.05 - 0.17 ppm and 0.0124 - 0.0390 ppm respectively. (author)

Release behavior of triazine residues in stabilised contaminated soils

International Nuclear Information System (INIS)

Ying, G.G.; Kookana, R.S.; Mallavarpu, M.

2005-01-01

This paper reports the release behavior of two triazines (atrazine and simazine) in stabilised soils from a pesticide-contaminated site in South Australia. The soils were contaminated with a range of pesticides, especially with triazine herbicides. With multiple extractions of each soil sample with deionised water (eight in total), 15% of atrazine and 4% of simazine residues were recovered, resulting in very high concentrations of the two herbicides in leachate. The presence of small fractions of surfactants was found to further enhance the release of the residues. Methanol content up to 10% did not substantially influence the concentration of simazine and atrazine released. The study demonstrated that while the stabilisation of contaminated soil with particulate activated carbon (5%) and cement mix (15%) was effective in locking the residues of some pesticides, it failed to immobilise triazine herbicides residues completely. Given the higher water solubility of these herbicides than other compounds more effective strategies to immobilise their residues is needed. - Stabilisation of contaminated soil with a mix of activated carbon and cement may fail to immobilise some contaminants like triazines

Applications of bauxite residue: A mini-review.

Science.gov (United States)

Verma, Ajay S; Suri, Narendra M; Kant, Suman

2017-10-01

Bauxite residue is the waste generated during alumina production by Bayer's process. The amount of bauxite residue (40-50 wt%) generated depends on the quality of bauxite ore used for the processing. High alkalinity and high caustic content in bauxite residue causes environmental risk for fertile soil and ground water contamination. The caustic (NaOH) content in bauxite residue leads to human health risks, like dermal problems and irritation to eyes. Moreover, disposal of bauxite residue requires a large area; such problems can only be minimised by utilising bauxite residue effectively. For two decades, bauxite residue has been used as a binder in cement industries and filler/reinforcement for composite materials in the automobile industry. Valuable metals and oxides, like alumina (Al 2 O 3 ), titanium oxide (TiO 2 ) and iron oxide Fe 2 O 3 , were extracted from bauxite residue to reduce waste. Bauxite residue was utilised in construction and structure industries to make geopolymers. It was also used in the making of glass-ceramics and a coating material. Recently bauxite residue has been utilised to extract rare earth elements like scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd) and dysprosium (Dy). In this review article, the mineralogical characteristics of bauxite residue are summarised and current progresses on utilisation of bauxite residue in different fields of science and engineering are presented in detail.

Hydrogenation upgrading of heavy oil residues

Energy Technology Data Exchange (ETDEWEB)

Krichko, A.A.; Maloletnev, A.S.; Mazneva, O.A.; Galkina, N.I. [Fossil Fuel Inst., Moscow (Russian Federation). Hydrogenation and Gasification Dept.; Suvorov, U.P.; Khadjiev, S.N. [Inst. Oil and Chemical Synthesis, Moscow (Russian Federation). Hydrogenation of Heavy Residues Dept.

1997-12-31

At present time in the world there is no simple and effective technology at low pressure (<15-20 MPa) which could give the opportunity to use oil residues for distillate fractions production. In Russia a process for hydrogenation (up 6 MPa hydrogen pressure) of high boiling point (b.p. >520 C) oil products, including high S, V and Ni contents ones, into distillates, feedstock for catalytic cracking (b.p. 360-520 C) and metal concentrates. The main point of the new process is as follows: the water solution of catalytic additive, for which purpose water soluble metal salts of VI-VIII groups are used, is mixed with heavy oil residues, dispersed and then subjected to additional supercavitation in a special apparatus. (orig.)

The pressure suppression system

International Nuclear Information System (INIS)

Aust, E.

1985-01-01

Nuclear plants with boiling water reactors have a safety containment with a pressure suppression system (PSS). Proceeding on significant self-developments, today the three PSS-lines of General Electric Co. (GE), Kraftwerk Union AG (KWU) and ASEA-ATOM are predominant, which are currently represented by the MARK III type, the KWU type 72 and the BWR 75 containment. In addition, there are special developments for the nuclear ship propulsion and for the pressurized water reactors in the Soviet Union. Key design values of the PSS allow a first valuation of its loads during a hypothetical loss-of-coolant accident. (orig.) [de

Analytic examination of mechanism for compressive residual stress introduction with low plastic strain using peening

International Nuclear Information System (INIS)

Ishibashi, Ryo; Hato, Hisamitsu; Miyazaki, Katsumasa; Yoshikubo, Fujio

2016-01-01

Our goal for this study was to understand the cause of the differences in surface properties between surfaces processed using water jet peening (WJP) and shot peening (SP) and to examine the compressive residual stress introduction process with low plastic strain using SP. The dynamic behaviors of stress and strain in surfaces during these processes were analyzed through elasto-plastic calculations using a finite-element method program, and the calculated results were compared with measured results obtained through experiments. Media impacting a surface results in a difference in the hardness and microstructure of the processed surface. During SP, a shot deforms the surface locally with stress concentration in the early stages of the impact, while shock waves deform the surface evenly throughout the wave passage across the surface during WJP. A shot with a larger diameter creates a larger impact area on the surface during shot impact. Thus, SP with a large-diameter shot suppresses the stress concentration under the same kinetic energy condition. As the shot diameter increases, the equivalent plastic strain decreases. On the other hand, the shot is subject to size restriction since the calculated results indicate the compressive residual stress at the surface decreased and occasionally became almost zero as the shot diameter increased. Thus, compressive residual stress introduction with low plastic strain by using SP is considered achievable by using shots with a large diameter and choosing the appropriate peening conditions. (author)

Insights into the mechanisms of mercury sorption onto aluminum based drinking water treatment residuals.

Science.gov (United States)

Deliz Quiñones, Katherine; Hovsepyan, Anna; Oppong-Anane, Akua; Bonzongo, Jean-Claude J

2016-04-15

Several studies have demonstrated the ability of drinking water treatment residuals (WTRs) to efficiently sorb metal cations from aqueous solutions. Reported results have stimulated interest on the potential use of WTRs as sorbent for metal removal from contaminated aqueous effluents as well as in metal immobilization in contaminated soils. However, knowledge on mechanisms of metal sorption by WTRs remains very limited and data on the long-term stability of formed metal-WTR complexes as a function of changing key environmental parameters are lacking. In this study, chemical selective sequential extraction (SSE), scanning electron microscopy combined with X-ray energy dispersive spectrometer (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) were used to gain insight into the different mechanisms of mercury (Hg) binding to aluminum based WTR (Al-WTRs). Results from sorption studies show that a significant portion of Hg becomes incorporated in the operationally defined residual fraction of Al-WTRs, and therefore, not prone to dissolution and mobility. The results of solid phase analyses suggested that Hg immobilization by Al-WTR occurs largely through its binding to oxygen donor atoms of mineral ligands driven by a combination of electrostatic forces and covalent bonding. Copyright © 2016 Elsevier B.V. All rights reserved.

Environmental impact of APC residues from municipal solid waste incineration: reuse assessment based on soil and surface water protection criteria.

Science.gov (United States)

Quina, Margarida J; Bordado, João C M; Quinta-Ferreira, Rosa M

2011-01-01

Waste management and environmental protection are mandatory requirements of modern society. In our study, air pollution control (APC) residues from municipal solid waste incinerators (MSWI) were considered as a mixture of fly ash and fine particulate solids collected in scrubbers and fabric filters. These are hazardous wastes and require treatment before landfill. Although there are a number of treatment options, it is highly recommended to find practical applications rather than just dump them in landfill sites. In general, for using a construction material, beyond technical specifications also soil and surface water criteria may be used to ensure environmental protection. The Dutch Building Materials Decree (BMD) is a valuable tool in this respect and it was used to investigate which properties do not meet the threshold criteria so that APC residues can be further used as secondary building material. To this end, some scenarios were evaluated by considering release of inorganic species from unmoulded and moulded applications. The main conclusion is that the high amount of soluble salts makes the APC residues a building material prohibited in any of the conditions tested. In case of moulding materials, the limits of heavy metals are complied, and their use in Category 1 would be allowed. However, also in this case, the soluble salts lead to the classification of "building material not allowed". The treatments with phosphates or silicates are able to solve the problem of heavy metals, but difficulties with the soluble salts are still observed. This analysis suggests that for APC residues to comply with soil and surface water protection criteria to be further used as building material at least a pre-treating for removing soluble salts is absolutely required. Copyright © 2011 Elsevier Ltd. All rights reserved.

NOESY-WaterControl: a new NOESY sequence for the observation of under-water protein resonances

International Nuclear Information System (INIS)

Torres, Allan M.; Zheng, Gang; Price, William S.

2017-01-01

Highly selective and efficient water signal suppression is indispensable in biomolecular 2D nuclear Overhauser effect spectroscopy (NOESY) experiments. However, the application of conventional water suppression schemes can cause a significant or complete loss of the biomolecular resonances at and around the water chemical shift (ω 2 ). In this study, a new sequence, NOESY-WaterControl, was developed to address this issue. The new sequence was tested on lysozyme and bovine pancreatic trypsin inhibitor (BPTI), demonstrating its efficiency in both water suppression and, more excitingly, preserving water-proximate biomolecular resonances in ω 2 . The 2D NOESY maps obtained using the new sequence thus provide more information than the maps obtained with conventional water suppression, thereby lessening the number of experiments needed to complete resonance assignments of biomolecules. The 2D NOESY-WaterControl map of BPTI showed strong bound water and exchangeable proton signals in ω 1 but these signals were absent in ω 2 , indicating the possibility of using the new sequence to discriminate bound water and exchangeable proton resonances from non-labile proton resonances with similar chemical shifts to water.

The effect of plant water storage on water fluxes within the coupled soil-plant system.

Science.gov (United States)

Huang, Cheng-Wei; Domec, Jean-Christophe; Ward, Eric J; Duman, Tomer; Manoli, Gabriele; Parolari, Anthony J; Katul, Gabriel G

2017-02-01

In addition to buffering plants from water stress during severe droughts, plant water storage (PWS) alters many features of the spatio-temporal dynamics of water movement in the soil-plant system. How PWS impacts water dynamics and drought resilience is explored using a multi-layer porous media model. The model numerically resolves soil-plant hydrodynamics by coupling them to leaf-level gas exchange and soil-root interfacial layers. Novel features of the model are the considerations of a coordinated relationship between stomatal aperture variation and whole-system hydraulics and of the effects of PWS and nocturnal transpiration (Fe,night) on hydraulic redistribution (HR) in the soil. The model results suggest that daytime PWS usage and Fe,night generate a residual water potential gradient (Δψp,night) along the plant vascular system overnight. This Δψp,night represents a non-negligible competing sink strength that diminishes the significance of HR. Considering the co-occurrence of PWS usage and HR during a single extended dry-down, a wide range of plant attributes and environmental/soil conditions selected to enhance or suppress plant drought resilience is discussed. When compared with HR, model calculations suggest that increased root water influx into plant conducting-tissues overnight maintains a more favorable water status at the leaf, thereby delaying the onset of drought stress. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

[Influence of water deficit and supplemental irrigation on nitrogen uptake by winter wheat and nitrogen residual in soil].

Science.gov (United States)

Wang, Zhaohui; Wang, Bing; Li, Shengxiu

2004-08-01

Pot experiment in greenhouse showed that water deficit at all growth stages and supplemental irrigation at tillering stage significantly decreased the nitrogen uptake by winter wheat and increased the mineral N residual (79.8-113.7 mg x kg(-1)) in soil. Supplemental irrigation at over-wintering, jointing or filling stage significantly increased the nitrogen uptake by plant and decreased the nitrogen residual (47.2-60.3 mg x kg(-1)) in soil. But, the increase of nitrogen uptake caused by supplemental irrigation did not always mean a high magnitude of efficient use of nitrogen by plants. Supplemental irrigation at over-wintering stage didn't induce any significant change in nitrogen content of grain, irrigation at filling stage increased the nitrogen content by 20.9%, and doing this at jointing stage decreased the nitrogen content by 19.6%, as compared to the control.

Pesticide residue determination in surface waters by stir bar sorptive extraction and liquid chromatography/tandem mass spectrometry.

Science.gov (United States)

Giordano, A; Fernández-Franzón, M; Ruiz, M J; Font, G; Picó, Y

2009-03-01

In this stir bar sorptive extraction (SBSE) method, 16 pesticides were extracted from surface water samples by sorption onto 1 mm polydimethylsiloxane layer coated on a 10-mm-length stir bar magnet. After liquid desorption of the analytes with 1 ml of methanol, the detection was performed on a liquid chromatography-tandem mass spectrometry with a triple quadrupole (QqQ) analyzer using selected reaction monitoring mode via electrospray ionization. Parameters affecting SBSE operation, including sample volume, salt addition, extraction time, stirring rate, and desorption conditions, have been evaluated. The optimized SBSE method required two 50 ml aliquots of surface water samples, one aliquot was added of 30% NaCl and stirred at 900 rpm during 1 h for testing five pesticides with log K(o/w) 3. The method was validated in spiked surface water samples at limits of quantifications (LOQs) and ten times the LOQs showing recoveries Albufera Lake and surrounding channels, showing that SBSE is a powerful tool for routine control analysis of pesticide residues in surface water.

A set of constitutive relationships accounting for residual NAPL in the unsaturated zone.

Science.gov (United States)

Wipfler, E L; van der Zee, S E

2001-07-01

Although laboratory experiments show that non-aqueous phase liquid (NAPL) is retained in the unsaturated zone, no existing multiphase flow model has been developed to account for residual NAPL after NAPL drainage in the unsaturated zone. We developed a static constitutive set of saturation-capillary pressure relationships for water, NAPL and air that accounts for both this residual NAPL and entrapped NAPL. The set of constitutive relationships is formulated similarly to the set of scaled relationships that is frequently applied in continuum models. The new set consists of three fluid-phase systems: a three-phase system and a two-phase system, that both comply with the original constitutive model, and a newly introduced residual NAPL system. The new system can be added relatively easily to the original two- and three-phase systems. Entrapment is included in the model. The constitutive relationships of the non-drainable residual NAPL system are based on qualitative fluid behavior derived from a pore scale model. The pore scale model reveals that the amount of residual NAPL depends on the spreading coefficient and the water saturation. Furthermore, residual NAPL is history-dependent. At the continuum scale, a critical NAPL pressure head defines the transition from free, mobile NAPL to residual NAPL. Although the Pc-S relationships for water and total liquid are not independent in case of residual NAPL, two two-phase Pc-S relations can represent a three-phase residual system of Pc-S relations. A newly introduced parameter, referred to as the residual oil pressure head, reflects the mutual dependency of water and oil. Example calculations show consistent behavior of the constitutive model. Entrapment and retention in the unsaturated zone cooperate to retain NAPL. Moreover, the results of our constitutive model are in agreement with experimental observations.

New technologies for fire suppression on board naval craft, FiST

NARCIS (Netherlands)

Rahm, M.; Hiltz, J.; Wal, R. van der; Hertzberg, T.; Lindström, J.

2014-01-01

For three years Canada, Sweden and the Netherlands have been investigating new technologies for fire suppression on board naval crafts within the FiST project. The project has focused on a number of technologies. These included the evaluation of water based fire suppression systems and in particular

Simultaneous determination of inorganic anions and cations in explosive residues by ion chromatography.

Science.gov (United States)

Meng, Hong-Bo; Wang, Tian-Ran; Guo, Bao-Yuan; Hashi, Yuki; Guo, Can-Xiong; Lin, Jin-Ming

2008-07-15

A non-suppressed ion chromatographic method by connecting anion-exchange and cation-exchange columns directly was developed for the separation and determination of five inorganic anions (sulfate, nitrate, chloride, nitrite, and chlorate) and three cations (sodium, ammonium, and potassium) simultaneously in explosive residues. The mobile phase was composed of 3.5mM phthalic acid with 2% acetonitrile and water at flow rate of 0.2 mL/min. Under the optimal conditions, the eight inorganic ions were completely separated and detected simultaneously within 16 min. The limits of detection (S/N=3) of the anions and cations were in the range of 50-100 microg/L and 150-320 microg/L, respectively, the linear correlation coefficients were 0.9941-0.9996, and the R.S.D. of retention time and peak area were 0.10-0.29% and 5.65-8.12%, respectively. The method was applied successfully to the analysis of the explosive samples with satisfactory results.

Microscopic bubble behaviour in suppression pool during wetwell venting

Science.gov (United States)

Zablackaite, G.; Nagasaka, H.; Kikura, H.

2017-10-01

During a severe accident PCV failure should be avoided and fission products inside PCV should be confined as much as possible. In order to minimize FPs release, Wetwell venting is conducted by releasing steam-non-condensable gas mixture carrying FPs from the Drywell to Suppression Pool. Steam is condensed by subcooled water in the pool, and most of FPs are retained into water. The removal of FP in the water pool is referred to as “Pool Scrubbing effect”. Hydrodynamic parameters of bubbles have impact on pool scrubbing effect. However, there is only few data available to evaluate quantitatively the bubble behaviour under depressurization and/or thermal stratification conditions. Series of experiments were conducted to evaluate the influence of temperature distribution, non-condensable gas content and pressure in the Wetwell on bubble behaviour. Bubbles were visualized using High Speed Camera and adopting shadowgraphy technique. Applying Particle Tracking Velocimetry, bubble velocity and size distribution were obtained from recorded images. Experimental results show that with increasing suppression pool temperature, bubbles reaching the pool surface decreased in size and traveling velocity became slower. In pressurized wetwell, bubble behaviour was similar to that in the heated up suppression pool case, although bubble parameters were similar to the low temperature case. Higher air content induced water surface movement and bubbles were smaller due to break up.

[Suppression of tinnitus by band noise masker--a study of 600 cases].

Science.gov (United States)

Watanabe, K; Kamio, T; Ohkawara, D; Aoki, H; Baba, S; Yagi, T

1997-09-01

We performed Band Noise Masker (BNM) therapy for the suppression of tinnitus in 600 patients and measured the pitch, loudness and masking level of tinnitus and residual inhibition (RI). We examined the efficiency of BNM therapy. The purpose of this study was to investigate the mechanism of suppression of tinnitus by BNM. Tinnitus was suppressed in 394 patients (66%) after BNM therapy. In the group of patients in whom we suppressed tinnitus, the loudness of tinnitus was reduced from 7.7 +/- 5.7dBSL to 7.5 +/- 5.5dBSL (p pitch of tinnitus did not exhibit a marked change. In the group of patients in whom we did not suppress tinnitus, the loudness and pitch of tinnitus did not exhibit a marked change. The efficiency of BNM therapy was high in the cases of presbyacusis and low in the cases of sudden deafness. There was no significant relationship between RI and the efficiency of BNM therapy. We examined these data and discussed the mechanism of suppression of tinnitus by BNM therapy. In all cases, after BNM therapy, the auditory threshold did not become worse. In 4 cases tinnitus became worse temporarily. In conclusion, BNM therapy is an effective mode for tinnitus control, is easily performed in our outpatient clinic or at home, and has no serious complications.

Suppression of surface effect by using bent-perfect-crystal monochromator in residual strain scanning

Czech Academy of Sciences Publication Activity Database

Vrána, Miroslav; Mikula, Pavol

490/491, - (2005), s. 234-238 ISSN 0255-5476 R&D Projects: GA ČR GA202/03/0891; GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z1048901 Keywords : neutron diffraction * residual strain scanning * bent monochromator Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.399, year: 2005

NOESY-WaterControl: a new NOESY sequence for the observation of under-water protein resonances

Energy Technology Data Exchange (ETDEWEB)

Torres, Allan M.; Zheng, Gang, E-mail: g.zheng@westernsydney.edu.au; Price, William S. [Western Sydney University, Nanoscale Organisation and Dynamics Group, School of Science and Health (Australia)

2017-03-15

Highly selective and efficient water signal suppression is indispensable in biomolecular 2D nuclear Overhauser effect spectroscopy (NOESY) experiments. However, the application of conventional water suppression schemes can cause a significant or complete loss of the biomolecular resonances at and around the water chemical shift (ω{sub 2}). In this study, a new sequence, NOESY-WaterControl, was developed to address this issue. The new sequence was tested on lysozyme and bovine pancreatic trypsin inhibitor (BPTI), demonstrating its efficiency in both water suppression and, more excitingly, preserving water-proximate biomolecular resonances in ω{sub 2}. The 2D NOESY maps obtained using the new sequence thus provide more information than the maps obtained with conventional water suppression, thereby lessening the number of experiments needed to complete resonance assignments of biomolecules. The 2D NOESY-WaterControl map of BPTI showed strong bound water and exchangeable proton signals in ω{sub 1} but these signals were absent in ω{sub 2}, indicating the possibility of using the new sequence to discriminate bound water and exchangeable proton resonances from non-labile proton resonances with similar chemical shifts to water.

Feasibility of using drinking water treatment residuals as a novel chlorpyrifos adsorbent.

Science.gov (United States)

Zhao, Yuanyuan; Wang, Changhui; Wendling, Laura A; Pei, Yuansheng

2013-08-07

Recent efforts have increasingly focused on the development of low-cost adsorbents for pesticide retention. In this work, the novel reuse of drinking water treatment residuals (WTRs), a nonhazardous ubiquitous byproduct, as an adsorbent for chlorpyrifos was investigated. Results showed that the kinetics and isothermal processes of chlorpyrifos sorption to WTRs were better described by a pseudo-second-order model and by the Freundlich equation, respectively. Moreover, compared with paddy soil and other documented absorbents, the WTRs exhibited a greater affinity for chlorpyrifos (log Koc = 4.76-4.90) and a higher chlorpyrifos sorption capacity (KF = 5967 mg(1-n)·L·kg(-1)) owing to the character and high content of organic matter. Further investigation demonstrated that the pH had a slight but statistically insignificant effect on chlorpyrifos sorption to WTRs; solution ionic strength and the presence of low molecular weight organic acids both resulted in concentration-dependent inhibition effects. Overall, these results confirmed the feasibility of using WTRs as a novel chlorpyrifos adsorbent.

Environmental impact of APC residues from municipal solid waste incineration: Reuse assessment based on soil and surface water protection criteria

International Nuclear Information System (INIS)

Quina, Margarida J.; Bordado, Joao C.M.; Quinta-Ferreira, Rosa M.

2011-01-01

Highlights: → The Dutch Building Material Decree (BMD) was used to APC residues from MSWI. → BMD is a straightforward tool to calculate expectable loads to the environment of common pollutants. → Chloride load to the environment lead to classification of building material not allowed. → At least a pre-treatment (e.g. washing) is required in order to remove soluble salts. → The stabilization with phosphates or silicates eliminate the problem of heavy metals. - Abstract: Waste management and environmental protection are mandatory requirements of modern society. In our study, air pollution control (APC) residues from municipal solid waste incinerators (MSWI) were considered as a mixture of fly ash and fine particulate solids collected in scrubbers and fabric filters. These are hazardous wastes and require treatment before landfill. Although there are a number of treatment options, it is highly recommended to find practical applications rather than just dump them in landfill sites. In general, for using a construction material, beyond technical specifications also soil and surface water criteria may be used to ensure environmental protection. The Dutch Building Materials Decree (BMD) is a valuable tool in this respect and it was used to investigate which properties do not meet the threshold criteria so that APC residues can be further used as secondary building material. To this end, some scenarios were evaluated by considering release of inorganic species from unmoulded and moulded applications. The main conclusion is that the high amount of soluble salts makes the APC residues a building material prohibited in any of the conditions tested. In case of moulding materials, the limits of heavy metals are complied, and their use in Category 1 would be allowed. However, also in this case, the soluble salts lead to the classification of 'building material not allowed'. The treatments with phosphates or silicates are able to solve the problem of heavy metals, but

Levels of pesticides residues in the White Nile water in the Sudan.

Science.gov (United States)

Nesser, Gibreel A A; Abdelbagi, Azhari O; Hammad, Ahmed Mohammed Ali; Tagelseed, Mirghani; Laing, Mark D

2016-06-01

Twenty-two commonly used pesticides were monitored during autumn, winter, and summer of 2004-2005 in 27 water samples from three sites along the White Nile in Sudan (former Sudan). Sites were selected to reflect pesticides gathered from drainage canals in central Sudan and from upstream sources. Collected samples were extracted and subjected to gas chromatographic analysis. Pesticides levels were measured in nanograms per liter. Pesticides residues were detected in 96 % of the samples with a total residue burden of 4132.6 ng L(-1), and an overall mean concentration and range of 50.99 and not detected-1570 ng L(-1), respectively. Ororganochlorines were the most frequently detected contaminants, which were found in 70 % of the samples, causing a total burden of 2852.8 ng L(-1), followed by pyrethroids 15 % of the samples, with a total burden of 926.5 ng L(-1). The tested herbicides were detected in ˂4 % of the samples with a total burden of 353.3 ng L(-1), while organophosphorus levels were below the detection limit. The most frequent contaminants were the following: heptachlor and its epoxide (52 % of samples), followed by DDTs (dichlorodiphenyltrichloroethanes) (DDT and DDE, in 19 % of the samples), cypermethrin and fenvalerate (in 11 % of the samples), and pendimethalin (in oxyfluorfen were not detected in the analyzed samples. Generally, levels were least in autumn, and followed by summer and winter. Sources of contamination might include agricultural lands in central Sudan and upstream sources. Both recent and old contaminations were indicated.

Computer simulations of a 1/5-scale experiment of a Mark I boiler water reactor pressure-suppression system under hypothetical LOCA conditions

International Nuclear Information System (INIS)

Edwards, L.L.

1978-01-01

The CHAMP computer code was employed to simulate a plane-geometry cross section of a Mark I boiling water reactor toroidal pressure suppression system air discharge experiment under hypothetical loss-of-coolant accident conditions. The experiments were performed at the Lawrence Livermore Laboratory on a 1 / 5 -scale model of the Peach Bottom Nuclear Power Plant

Chemical Control of Black Flies in Large Rivers as an Impact in Agrochemical Residue-Biota Interactions in Water Ecosystems

International Nuclear Information System (INIS)

Haufe, W.O.

1981-01-01

Livestock losses have been an obstacle to economic development of the farming and livestock industry in more northerly areas of Canada until two species of black fly, Simulium arcticum and S. luggeri, outbreaks are controlled effectively. The problem is complicated by its association with an abundance of large rivers and streams. Since effective control of black flies is presently limited to reduction of their breeding sources in flowing water, the managers of Canadian inland waters have been concerned about any major practice of using pesticides as black fly larvicides. Consequently, Canadian inland waters have been subject to continuous monitoring of major drainage systems with special attention to the chlorinated hydrocarbon insecticides. The latest status of residues was published from a Canadian Survey of 333 sampling locations between 1972 and 1975

Mutagenicity of pan residues and gravy from fried meat.

Science.gov (United States)

Overvik, E; Nilsson, L; Fredholm, L; Levin, O; Nord, C E; Gustafsson, J A

1987-02-01

Lean pork meat was fried with or without the addition of frying-fat at 200 or 250 degrees C. The pan residues were collected by washing the hot pan with boiling water. When producing thickened gravy the water was substituted by a mixture of water and flour, milk and flour or cream and flour. The basic extracts were tested for mutagenicity in Ames' Salmonella test on strain TA98 with the addition of S9 mix. High amounts of mutagenicity were found in all samples. The amounts of mutagenicity in the pan residues were at a comparable level of the amounts found in the meat crusts. Thickening of the gravy caused only small changes in the mutagenicity.

Residual transpiration as a component of salinity stress tolerance mechanism: a case study for barley.

Science.gov (United States)

Hasanuzzaman, Md; Davies, Noel W; Shabala, Lana; Zhou, Meixue; Brodribb, Tim J; Shabala, Sergey

2017-06-19

While most water loss from leaf surfaces occurs via stomata, part of this loss also occurs through the leaf cuticle, even when the stomata are fully closed. This component, termed residual transpiration, dominates during the night and also becomes critical under stress conditions such as drought or salinity. Reducing residual transpiration might therefore be a potentially useful mechanism for improving plant performance when water availability is reduced (e.g. under saline or drought stress conditions). One way of reducing residual transpiration may be via increased accumulation of waxes on the surface of leaf. Residual transpiration and wax constituents may vary with leaf age and position as well as between genotypes. This study used barley genotypes contrasting in salinity stress tolerance to evaluate the contribution of residual transpiration to the overall salt tolerance, and also investigated what role cuticular waxes play in this process. Leaves of three different positions (old, intermediate and young) were used. Our results show that residual transpiration was higher in old leaves than the young flag leaves, correlated negatively with the osmolality, and was positively associated with the osmotic and leaf water potentials. Salt tolerant varieties transpired more water than the sensitive variety under normal growth conditions. Cuticular waxes on barley leaves were dominated by primary alcohols (84.7-86.9%) and also included aldehydes (8.90-10.1%), n-alkanes (1.31-1.77%), benzoate esters (0.44-0.52%), phytol related compounds (0.22-0.53%), fatty acid methyl esters (0.14-0.33%), β-diketones (0.07-0.23%) and alkylresorcinols (1.65-3.58%). A significant negative correlation was found between residual transpiration and total wax content, and residual transpiration correlated significantly with the amount of primary alcohols. Both leaf osmolality and the amount of total cuticular wax are involved in controlling cuticular water loss from barley leaves under well

Solid-phase extraction combined with high-performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry analysis of pesticides in water: method performance and application in a reconnaissance survey of residues in drinking water in Greater Cairo, Egypt.

Science.gov (United States)

Potter, Thomas L; Mohamed, Mahmoud A; Ali, Hannah

2007-01-24

Monitoring of water resources for pesticide residues is often needed to ensure that pesticide use does not adversely impact the quality of public water supplies or the environment. In many rural areas and throughout much of the developing world, monitoring is often constrained by lack of testing facilities; thus, collection of samples and shipment to centralized laboratories for analysis is required. The portability, ease of use, and potential to enhance analyte stability make solid-phase extraction (SPE) an attractive technique for handling water samples prior to their shipment. We describe performance of an SPE method targeting a structurally diverse mixture of 25 current-use pesticides and two common degradates in samples of raw and filtered drinking water collected in Greater Cairo, Egypt. SPE was completed in a field laboratory in Egypt, and cartridges were shipped to the United States for elution and high-performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry analysis. Quantitative and reproducible recovery of 23 of 27 compounds (average = 96%; percent relative standard deviation = 21%) from matrix spikes (1 microg L-1 per component) prepared in the field and from deionized water fortified similarly in the analytical laboratory was obtained. Concurrent analysis of unspiked samples identified four parent compounds and one degradate in drinking water samples. No significant differences were observed between raw and filtered samples. Residue levels in all cases were below drinking water and "harm to aquatic-life" thresholds, indicating that human and ecological risks of pesticide contamination were relatively small; however, the study was limited in scale and scope. Further monitoring is needed to define spatial and temporal variation in residue concentrations. The study has demonstrated the feasibility of performing studies of this type using SPE to extract and preserve samples in the field. The approach should be broadly

Oxygen suppression in boiling water reactors. Phase 2. Annual report 1981, December 2, 1980-December 31, 1981

International Nuclear Information System (INIS)

Burley, E.L.

1982-07-01

A hydrogen addition test will be performed in the Dresden-2 reactor of Commonwealth Edison Company during 1982. Up to 2 ppM hydrogen will be added to and dissolved in the reactor feedwater to reverse the radiolysis reaction in the reactor core and suppress oxgen concentration in the primary coolant. At low oxygen levels the propensity of stressed and sensitized 304 stainless steel toward intergranular stress corrosion cracking is greatly reduced. The test will answer outstanding questions and uncertainties in the areas of water chemistry, equipment design and materials performance. Nine special sample facilities will be prepared in the primary coolant, main stream, feedwater/condensate, and offgas systems. Instrumentation will be available to measure hydrogen, oxygen, conductivity, pH, soluble and insoluble corrosion products, and electrochemical potentials. In addition, an autoclave in which confirming constant extension rate tests can be conducted in reactor water will be provided

Measurement of conformational constraints in an elastin-mimetic protein by residue-pair selected solid-state NMR

Energy Technology Data Exchange (ETDEWEB)

Hong, Mei [Iowa State University, Department of Chemistry (United States)], E-mail: mhong@iastate.edu; McMillan, R. Andrew; Conticello, Vincent P. [Emory University, Department of Chemistry (United States)

2002-02-15

We introduce a solid-state NMR technique for selective detection of a residue pair in multiply labeled proteins to obtain site-specific structural constraints. The method exploits the frequency-offset dependence of cross polarization to achieve {sup 13}CO{sub i} {sup {yields}} {sup 15}N{sub i} {sup {yields}} {sup 13}C{alpha}{sub i} transfer between two residues. A {sup 13}C, {sup 15}N-labeled elastin mimetic protein (VPGVG){sub n} is used to demonstrate the method. The technique selected the Gly3 C{alpha} signal while suppressing the Gly5 C{alpha} signal, and allowed the measurement of the Gly3 C{alpha} chemical shift anisotropy to derive information on the protein conformation. This residue-pair selection technique should simplify the study of protein structure at specific residues.

Pressure suppression system for a nuclear reactor

International Nuclear Information System (INIS)

Jost, N.

1977-01-01

The invention pertains to a pressure suppression system for PWR reactors where the parts enclosing the primary coolant are contained in two pressure-tight separate chambers. According to the invention, these chambers are partly filled with water and are connected with each other below the water surface. This way, gases cannot escape from the containment, not even if a valve and a line are damaged at the same time, as the vapours released condensate in the water of at least one of the other chambers. (HP) [de

Wing rock suppression using forebody vortex control

Science.gov (United States)

Ng, T. T.; Ong, L. Y.; Suarez, C. J.; Malcolm, G. N.

1991-01-01

Static and free-to-roll tests were conducted in a water tunnel with a configuration that consisted of a highly-slender forebody and 78-deg sweep delta wings. Flow visualization was performed and the roll angle histories were obtained. The fluid mechanisms governing the wing rock of this configuration were identified. Different means of suppressing wing rock by controlling the forebody vortices using small blowing jets were also explored. Steady blowing was found to be capable of suppressing wing rock, but significant vortex asymmetries had to be induced at the same time. On the other hand, alternating pulsed blowing on the left and right sides of the forebody was demonstrated to be potentially an effective means of suppressing wing rock and eliminating large asymmetric moments at high angles of attack.

SBWR PCCS vent phenomena and suppression pool mixing

Energy Technology Data Exchange (ETDEWEB)

Coddington, P. [Thermal-Hydraulics Lab., Paul Scherrer Institute, Villigen (Switzerland); Andreani, M. [Nuclear Engineering Lab., Swiss Federal Institute of Technology, Zurich (Switzerland)

1995-09-01

The most important phenomena influencing the effectiveness of the pressure suppression capability of the water pool within the Wetwell compartment of the SBWR Containment, during the period of Passive Containment Cooling System (PCCS) venting, have been critically reviewed. In addition, calculations have been carried-out to determine the condensation of the vented steam and the distribution of the energy deposited in the liquid pool. It has been found that a large contribution to the vapour suppression is due to condensation inside the vent pipe. The condensation rate of the steam inside the bubbles, produced at the vent exit, during their rise to the surface, may however be rather low, because of the large size bubbles. This can lead to vapour channelling to the Wetwell gas space. The above comments are likely to be ameliorated if the vent exit is a distributed source or sparger. Due to the large water flow rates within the {open_quotes}bubbly two-phase plume{close_quotes} generated by the gas injection, the water in the pool above the vent exit is likely to be heated nearly isothermally (perfect mixing). The effect of the suppression pool walls would be to enhance the recirculation and, consequently to promote mixing. The large size of the bubbles therein and of the walls on pool mixing are the most severe difficulties in extrapolating the results from scaled experiments to prototypical conditions.

Use of Fe/Al drinking water treatment residuals as amendments for enhancing the retention capacity of glyphosate in agricultural soils.

Science.gov (United States)

Zhao, Yuanyuan; Wendling, Laura A; Wang, Changhui; Pei, Yuansheng

2015-08-01

Fe/Al drinking water treatment residuals (WTRs), ubiquitous and non-hazardous by-products of drinking water purification, are cost-effective adsorbents for glyphosate. Given that repeated glyphosate applications could significantly decrease glyphosate retention by soils and that the adsorbed glyphosate is potentially mobile, high sorption capacity and stability of glyphosate in agricultural soils are needed to prevent pollution of water by glyphosate. Therefore, we investigated the feasibility of reusing Fe/Al WTR as a soil amendment to enhance the retention capacity of glyphosate in two agricultural soils. The results of batch experiments showed that the Fe/Al WTR amendment significantly enhanced the glyphosate sorption capacity of both soils (pretention capacity in soils. Copyright © 2015. Published by Elsevier B.V.

Residual Stresses in a NiCrY-Coated Powder Metallurgy Disk Superalloy

Science.gov (United States)

Gabb, Timothy P.; Rogers, Richard B.; Nesbitt, James A.; Puleo, Bernadette J.; Miller, Robert A.; Telesman, Ignacy; Draper, Susan L.; Locci, Ivan E.

2017-01-01

Protective ductile coatings will be necessary to mitigate oxidation and corrosion attack on superalloy disks exposed to increasing operating temperatures in some turbine engine environments. However, such coatings must be resistant to harmful surface cracking during service. The objective of this study was to investigate how residual stresses evolve in such coatings. Cylindrical gage fatigue specimens of powder metallurgy-processed disk superalloy LSHR were coated with a NiCrY coating, shot peened, and then subjected to fatigue in air at room and high temperatures. The effects of shot peening and fatigue cycling on average residual stresses and other aspects of the coating were assessed. Shot peening did induce beneficial compressive residual stresses in the coating and substrate. However, these stresses became more tensile in the coating with subsequent heating and contributed to cracking of the coating in long intervals of cycling at 760 C. Substantial compressive residual stresses remained in the substrate adjacent to the coating, sufficient to suppress fatigue cracking. The coating continued to protect the substrate from hot corrosion pitting, even after fatigue cracks initiated in the coating.

Combining physico-chemical analysis with a Daphnia magna bioassay to evaluate a recycling technology for drinking water treatment plant waste residuals.

Science.gov (United States)

Chen, Ting; Xu, Yongpeng; Zhu, Shijun; Cui, Fuyi

2015-12-01

Recycling water treatment plant (WTP) waste residuals is considered to be a feasible method to enhance the efficiency of pollutant removal. This study also evaluated the safety and water quality of a pilot-DWTP waste residuals recycling technology by combining physical-chemistry analysis with a Daphnia magna assay. The water samples taken from each treatment step were extracted and concentrated by XAD-2 resin and were then analyzed for immobilization and enzyme activity with D. magna. The measured parameters, such as the dissolve organic carbon (DOC), UV254 and THM formation potential (THMFPs) of the recycling process, did not obviously increase over 15 days of continuous operation and were even lower than typical values from a conventional process. The extract concentration ranged from 0 to 2 Leq/ml as measured on the 7th and 15th days and the immobilization of D. magna exposed to water treated by the recycling process was nearly equivalent to that of the conventional process. Both the superoxide dismutase (SOD) and the catalase (CAT) activity assay indicated that a lower dose of water extract (0.5, 1, 1.5 Leq/ml) could stimulate the enzyme activity of D. magna, whereas a higher dose (2 Leq/ml at the sampling point C3, R3, R4 ) inhibits the activity. Moreover, the SOD and CAT activity of D. magna with DOC and UV254 showed a strong concentration-effect relationship, where the concentration range of DOC and UV254 were 4.1-16.2 mg/L and 0.071-4.382 cm(-1), respectively. The results showed that there was no statistically significant difference (p>0.05) between the conventional and recycling treatment processes and the toxicity of water samples in the recycling process did not increase during the 15-day continuous recycling trial. Copyright © 2015 Elsevier Inc. All rights reserved.

New EDTA determination method based on ion chromatography with suppressed conductimetric detection

International Nuclear Information System (INIS)

Gyoergy Patzay; Yahya Ramadan; Csilla Tonko

2014-01-01

A novel direct method for the determination of EDTA in alkaline radioactive evaporator residue solution was developed and validated based on ion chromatography with suppressed conductimetric detection and anion exchange columns (A Supp 4, 4 mm × 250 mm and A Supp 5, 4 mm × 150 mm). The yttrium-EDTA complex resulted one single chromatographic peak in the eluent and allowed the correct determination of EDTA in an alkaline, high concentration radioactive waste water. Depending on coexisting substances, suitable eluent is 10.0 mM carbonate buffer/pH 10.6 or 10.75 (t R ,Y-EDTA = 7.01 and 6.4 min, respectively). For 10.0 mM carbonate buffer/pH 10.6 and isocratic flow rate of 1.0 cm 3 /min, a linear calibration curve was obtained from 5 to 40 mg/dm 3 (r > 0.999) EDTA. Good resolution was achieved from commonly coexisting anions (chloride, nitrite, nitrate, sulphate, phosphate, bromide and citrate). The developed simple ion chromatographic method was applied for the assay of EDTA in various radioactive alkaline solutions. (author)

Purification of the Drain Water and Distillation Residues from Organic Compounds, Transuranic Elements and Uranium at the Chernobyl NPP

Directory of Open Access Journals (Sweden)

Rudenko, L.I.

2014-05-01

Full Text Available Article examines the purification of drain water and distillation residue from organic (polymeric compounds, tran suranic elements and uranium. We propose the pretreatment method with the use of a type «Sizol» coagulant-flocculant and catalytic oxidation with hydrogen peroxide and ultrafiltration. This method prevents evaporator coking by dustsuppression and other organic substances, which are vulcanized by heating. Removing alpha-emitting radionuclides increases safety level at the nuclear power plant.

Residual nilpotence and residual solubility of groups

International Nuclear Information System (INIS)

Mikhailov, R V

2005-01-01

The properties of the residual nilpotence and the residual solubility of groups are studied. The main objects under investigation are the class of residually nilpotent groups such that each central extension of these groups is also residually nilpotent and the class of residually soluble groups such that each Abelian extension of these groups is residually soluble. Various examples of groups not belonging to these classes are constructed by homological methods and methods of the theory of modules over group rings. Several applications of the theory under consideration are presented and problems concerning the residual nilpotence of one-relator groups are considered.

Physicochemical and functional characteristics of residual pulp of potato

Directory of Open Access Journals (Sweden)

Webber Tavares de CARVALHO

Full Text Available Abstract Starch-rich liquid effluent is generated after peeling, cutting and washing of tubers during the fries processing. After sedimentation of this effluent is recovered a wet residual pulp, and after drying is obtained dry residual pulp or simply named in this study residual pulp of potato (RPP. In order to convert the effluent into a material easy to store for long periods (such as the potato starch, which would make it suitable for various applications. The aim of this study was to evaluate the effect of the drying conditions, specifically variables temperature and air flow on the drying time and water activity, pH, titratable acidity, instrumental colour parameters, water absorption index, water solubility index and oil absorption capacity of dry RPP. Central Composite Design was used, with temperature levels from 50.0 to 70.0 °C and air flow from 0.06 to 0.092 m3 m–2 s–1. Temperature and airflow affected the study characteristics, except for lightness (L*, water solubility index and oil absorption capacity. It was concluded that milder conditions (lower temperatures and intermediate air flow resulted in higher-quality final products (lighter, less acidic, although requiring higher drying time. Therefore, depending on the product application, different drying conditions can be used.

Evaluation of Membrane Ultrafiltration and Residual Chlorination as a Decentralized Water Treatment Strategy for Ten Rural Healthcare Facilities in Rwanda

Directory of Open Access Journals (Sweden)

Alexandra Huttinger

2015-10-01

Full Text Available There is a critical need for safe water in healthcare facilities (HCF in low-income countries. HCF rely on water supplies that may require additional on-site treatment, and need sustainable technologies that can deliver sufficient quantities of water. Water treatment systems (WTS that utilize ultrafiltration membranes for water treatment can be a useful technology in low-income countries, but studies have not systematically examined the feasibility of this technology in low-income settings. We monitored 22 months of operation of 10 WTS, including pre-filtration, membrane ultrafiltration, and chlorine residual disinfection that were donated to and operated by rural HCF in Rwanda. The systems were fully operational for 74% of the observation period. The most frequent reasons for interruption were water shortage (8% and failure of the chlorination mechanism (7%. When systems were operational, 98% of water samples collected from the HCF taps met World Health Organization (WHO guidelines for microbiological water quality. Water quality deteriorated during treatment interruptions and when water was stored in containers. Sustained performance of the systems depended primarily on organizational factors: the ability of the HCF technician to perform routine servicing and repairs, and environmental factors: water and power availability and procurement of materials, including chlorine and replacement parts in Rwanda.

Influence of organic waste and residue mud additions on chemical, physical and microbial properties of bauxite residue sand.

Science.gov (United States)

Jones, Benjamin E H; Haynes, Richard J; Phillips, Ian R

2011-02-01

In an alumina refinery, bauxite ore is treated with sodium hydroxide at high temperatures and pressures and for every tone of alumina produced, about 2 tones of alkaline, saline bauxite processing waste is also produced. At Alcoa, a dry stacking system of disposal is used, and it is the sand fraction of the processing waste that is rehabilitated. There is little information available regarding the most appropriate amendments to add to the processing sand to aid in revegetation. The purpose of this study was to investigate how the addition of organic wastes (biosolids and poultry manure), in the presence or absence of added residue mud, would affect the properties of the residue sand and its suitability for revegetation. Samples of freshly deposited residue sand were collected from Alcoa's Kwinana refinery. Samples were treated with phosphogypsum (2% v/v), incubated, and leached. A laboratory experiment was then set up in which the two organic wastes were applied at 0 or the equivalent to 60 tones ha(-1) in combination with residue mud added at rates of 0%, 10% and 20% v/v. Samples were incubated for 8 weeks, after which, key chemical, physical and microbial properties of the residue sand were measured along with seed germination. Additions of residue mud increased exchangeable Na(+), ESP and the pH, and HCO (3) (-) and Na(+) concentrations in saturation paste extracts. Additions of biosolids and poultry manure increased concentrations of extractable P, NH (4) (+) , K, Mg, Cu, Zn, Mn and Fe. Addition of residue mud, in combination with organic wastes, caused a marked decrease in macroporosity and a concomitant increase in mesoporosity, available water holding capacity and the quantity of water held at field capacity. With increasing residue mud additions, the percentage of sample present as sand particles (2 mm diameter) increased; greatest aggregation occurred where a combination of residue mud and poultry manure were added. Stability of aggregates, as measured by

The flavonol epicatechin reverses the suppressive effects of a stressor on long-term memory formation.

Science.gov (United States)

Knezevic, Bogdan; Lukowiak, Ken

2014-11-15

Learning and subsequent memory formation are influenced by both environmental and lifestyle factors, such as stress and diet. Epicatechin, a plant flavonol found in cocoa, red wine and green tea enhances long-term memory (LTM) formation in Lymnaea. By contrast, an ecologically relevant stressor, low-calcium pond water, suppresses LTM formation. We tested the hypothesis that epicatechin overcomes the suppressive effects of the stressor on LTM formation in the continued presence of the stressor. Snails trained in low-calcium pond water exhibit learning but not LTM. Epicatechin (15 mg l(-1)) in control pond water enhances LTM formation. When epicatechin was added to the low-calcium pond water an enhanced LTM similar to that seen in control pond water was observed. Thus, a naturally occurring bioactive plant compound was able to overcome the suppressive effects of an ecologically relevant stressor on LTM formation. © 2014. Published by The Company of Biologists Ltd.

Final air test results for the 1/5-scale Mark I boiling water reactor pressure suppression experiment

International Nuclear Information System (INIS)

Collins, E.K.; Lai, W.

1977-01-01

A loss-of-coolant accident (LOCA) in a boiling-water reactor (BWR) power plant has never occurred. However, because this type of accident is particularly severe, it is used as a principal basis for design. During a hypothetical LOCA in a Mark I BWR, air followed by steam is injected from a drywell into a toroidal wetwell about half-filled with water. A series of consistent, versatile, and accurate air-water tests simulating LOCA conditions was completed in the Lawrence Livermore Laboratory 1/5-Scale Mark I BWR Pressure Suppression Experimental Facility. Results from this test series were used to quantify the vertical loading function and to study the associated fluid dynamic phenomena. Detailed histories of vertical loads on the wetwell are shown. In particular, variations of hydrodynamic-generated vertical loads with changes in drywell pressurization rate, downcomer submergence, and the vent-line loss coefficient are established. Initial drywell overpressure, which partially preclears the downcomers of water, substantially reduces the peak vertical loads. Scaling relationships, developed from dimensional analysis and verified by bench-top experiments, allow the 1/5-scale results to be applied to a full-scale BWR power plant. This analysis leads to dimensionless groupings which are invariant. These groupongs show that if water is used as the working fluid, the magnitude of the forces in a scaled facility is reduced by the cube of the scale factor; the time when these forces occur is reduced by the square root of the scale factor

ITER cryostat main chamber and vacuum vessel pressure suppression system design

International Nuclear Information System (INIS)

Ito, Akira; Nakahira, Masataka; Takahashi, Hiroyuki; Tada, Eisuke; Nakashima, Yoshitane; Ueno, Osamu

1999-03-01

Design of Cryostat Main Chamber and Vacuum Vessel Pressure Suppression System (VVPS) of International Thermonuclear Experimental Reactor (ITER) has been conducted. The cryostat is a cylindrical vessel that includes in-vessel component such as vacuum vessel, superconducting toroidal coils and poloidal coils. This cryostat provides the adiabatic vacuum about 10 -4 Pa for the superconducting coils operating at 4 K and forms the second confinement barrier to tritium. The adiabatic vacuum is to reduce thermal loads applied to the superconducting coils and their supports so as to keep their temperature 4 K. The VVPS consists of a suppression tank located under the lower bio-shield and 4 relief pipes to connect the vacuum vessel and the suppression tank. The VVPS is to keep the maximum pressure rise of the vacuum vessel below the design value of 0.5 MPa in case of the in-vessel LOCA (water spillage from in-vessel component). The spilled water and steam are lead to the suppression tank through the relief pipes when the internal pressure of vacuum vessel is over 0.2 MPa, and then the internal pressure is kept below 0.5 MPa. This report summarizes the structural design of the cryostat main chamber and pressure suppression system, together with their fabrication and installation. (author)

ITER cryostat main chamber and vacuum vessel pressure suppression system design

Energy Technology Data Exchange (ETDEWEB)

Ito, Akira; Nakahira, Masataka; Takahashi, Hiroyuki; Tada, Eisuke [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nakashima, Yoshitane; Ueno, Osamu

1999-03-01

Design of Cryostat Main Chamber and Vacuum Vessel Pressure Suppression System (VVPS) of International Thermonuclear Experimental Reactor (ITER) has been conducted. The cryostat is a cylindrical vessel that includes in-vessel component such as vacuum vessel, superconducting toroidal coils and poloidal coils. This cryostat provides the adiabatic vacuum about 10{sup -4} Pa for the superconducting coils operating at 4 K and forms the second confinement barrier to tritium. The adiabatic vacuum is to reduce thermal loads applied to the superconducting coils and their supports so as to keep their temperature 4 K. The VVPS consists of a suppression tank located under the lower bio-shield and 4 relief pipes to connect the vacuum vessel and the suppression tank. The VVPS is to keep the maximum pressure rise of the vacuum vessel below the design value of 0.5 MPa in case of the in-vessel LOCA (water spillage from in-vessel component). The spilled water and steam are lead to the suppression tank through the relief pipes when the internal pressure of vacuum vessel is over 0.2 MPa, and then the internal pressure is kept below 0.5 MPa. This report summarizes the structural design of the cryostat main chamber and pressure suppression system, together with their fabrication and installation. (author)

Selective weed suppression by cover crop residues: effects of seed mass and timing of species’sensitivity

NARCIS (Netherlands)

Kruidhof, H.M.; Gallandt, E.R.; Haramoto, E.R.; Bastiaans, L.

2011-01-01

Laboratory bioassays have shown that large-seeded species better tolerate cover crop residue–mediated stress than small-seeded species. This provides the potential for selective suppression of small-seeded weeds in large-seeded crops. We conducted two field experiments in which seedling emergence of

FIB-based measurement of local residual stresses on microsystems

Science.gov (United States)

Vogel, Dietmar; Sabate, Neus; Gollhardt, Astrid; Keller, Juergen; Auersperg, Juergen; Michel, Bernd

2006-03-01

The paper comprises research results obtained for stress determination on micro and nanotechnology components. It meets the concern of controlling stresses introduced to sensors, MEMS and electronics devices during different micromachining processes. The method bases on deformation measurement options made available inside focused ion beam equipment. Removing locally material by ion beam milling existing stresses / residual stresses lead to deformation fields around the milled feature. Digital image correlation techniques are used to extract deformation values from micrographs captured before and after milling. In the paper, two main milling features have been analyzed - through hole and through slit milling. Analytical solutions for stress release fields of in-plane stresses have been derived and compared to respective experimental findings. Their good agreement allows to settle a method for determination of residual stress values, which is demonstrated for thin membranes manufactured by silicon micro technology. Some emphasis is made on the elimination of main error sources for stress determination, like rigid body object displacements and rotations due to drifts of experimental conditions under FIB imaging. In order to illustrate potential application areas of the method residual stress suppression by ion implantation is evaluated by the method and reported here.

New technology for the emulsification of petroleum residuals in water; Nueva tecnologia para la emulsificacion de residuales del petroleo en agua

Energy Technology Data Exchange (ETDEWEB)

Peralta, M. Vita; Arriola, Alejandro M.; Sanchez S, Ramon; Manzanares P, Emilio; Romo M, Cesar A.; Yery de Coss P, R. [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

2001-07-01

It turns out of interest to Comision Federal de Electricidad and Petroleos Mexicanos to reduce costs of fuel oil, reducing the viscosity of the residues petroleum of high vacuum distillation emulsifying these with water. The parameters that define the characteristics of the emulsions are mainly the relation of their components, viscosity, size and drop distribution and its stability. The experimental work began producing emulsions in form of lots, using samples of approximately 500 milliliters of vacuum residue. In this first stage, at different concentrations, were examined eight different surfactants, as well as combinations among them, also seven different stabilizers were used. With these tests it has been managed to identify the concentrations, as well as the most adequate relations of surfactants and stabilizers for the production of emulsions of vacuum residues in water. The size and drop distribution has been determined by means of an optical LEICA microscope, model DMLS, that has adapted a photographic system in which an emulsion photo is obtained and, later, a system of analysis of images is used for obtaining of the values of the diameter of the drops present in the emulsion. Finally, by means of statistical software the average size of the particles is obtained, as well as the drop size distribution. The tests results of emulsions that remain fluid are shown and an example of the microstructure of an emulsion of vacuum residue-in-water is given. As well as an example of histogram of the drop size distribution of an emulsion of vacuum distillation-in-water, and another one of the viscosity in function of temperature at different cut efforts in one emulsion of vacuum distillate residue-in-water. [Spanish] Resulta de interes para la Comision Federal de Electricidad y Petroleos Mexicanos reducir costos del combustoleo, reduciendo la viscosidad de los residuos de vacio emulsionando estos en agua. Los parametros que definen las caracteristicas de las

Suppression of the Thermal Decomposition Reaction of Forest Combustible Materials in Large-Area Fires

Science.gov (United States)

Volkov, R. S.; Zhdanova, A. O.; Kuznetsov, G. V.; Strizhak, P. A.

2018-05-01

Experimental investigations on the characteristic time of suppression of the thermal decomposition reaction of typical forest combustible materials (aspen twigs, birch leaves, spruce needles, pine chips, and a mixture of these materials) and the volume of water required for this purpose have been performed for model fire hotbeds of different areas: SFCM = 0.0003-0.007 m2 and SFCM = 0.045-0.245 m2. In the experiments, aerosol water flows with droplets of size 0.01-0.25 mm were used for the spraying of model fire hotbeds, and the density of spraying was 0.02 L/(m2·s). It was established that the characteristics of suppression of a fire by an aerosol water flow are mainly determined by the sizes of the droplets in this flow. Prognostic estimates of changes in the dispersivity of a droplet cloud, formed from large (as large as 0.5 L) "drops" (water agglomerates) thrown down from a height, have been made. It is shown that these changes can influence the conditions and characteristics of suppression of a forest fire. Dependences, allowing one to forecast the characteristics of suppression of the thermal decomposition of forest combustible materials with the use of large water agglomerates thrown down from an aircraft and aerosol clouds formed from these agglomerates in the process of their movement to the earth, are presented.

Suppression of the Thermal Decomposition Reaction of Forest Combustible Materials in Large-Area Fires

Science.gov (United States)

Volkov, R. S.; Zhdanova, A. O.; Kuznetsov, G. V.; Strizhak, P. A.

2018-03-01

Experimental investigations on the characteristic time of suppression of the thermal decomposition reaction of typical forest combustible materials (aspen twigs, birch leaves, spruce needles, pine chips, and a mixture of these materials) and the volume of water required for this purpose have been performed for model fire hotbeds of different areas: SFCM = 0.0003-0.007 m2 and SFCM = 0.045-0.245 m2. In the experiments, aerosol water flows with droplets of size 0.01-0.25 mm were used for the spraying of model fire hotbeds, and the density of spraying was 0.02 L/(m2·s). It was established that the characteristics of suppression of a fire by an aerosol water flow are mainly determined by the sizes of the droplets in this flow. Prognostic estimates of changes in the dispersivity of a droplet cloud, formed from large (as large as 0.5 L) "drops" (water agglomerates) thrown down from a height, have been made. It is shown that these changes can influence the conditions and characteristics of suppression of a forest fire. Dependences, allowing one to forecast the characteristics of suppression of the thermal decomposition of forest combustible materials with the use of large water agglomerates thrown down from an aircraft and aerosol clouds formed from these agglomerates in the process of their movement to the earth, are presented.

Suppression of stratified explosive interactions

Energy Technology Data Exchange (ETDEWEB)

Meeks, M.K.; Shamoun, B.I.; Bonazza, R.; Corradini, M.L. [Wisconsin Univ., Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics

1998-01-01

Stratified Fuel-Coolant Interaction (FCI) experiments with Refrigerant-134a and water were performed in a large-scale system. Air was uniformly injected into the coolant pool to establish a pre-existing void which could suppress the explosion. Two competing effects due to the variation of the air flow rate seem to influence the intensity of the explosion in this geometrical configuration. At low flow rates, although the injected air increases the void fraction, the concurrent agitation and mixing increases the intensity of the interaction. At higher flow rates, the increase in void fraction tends to attenuate the propagated pressure wave generated by the explosion. Experimental results show a complete suppression of the vapor explosion at high rates of air injection, corresponding to an average void fraction of larger than 30%. (author)

Thermal Aging Effects on Residual Stress and Residual Strain Distribution on Heat Affected Zone of Alloy 600 in Dissimilar Metal Weld

Energy Technology Data Exchange (ETDEWEB)

Ham, Junhyuk; Choi, Kyoung Joon; Kim, Ji Hyun [UNIST, Ulsan (Korea, Republic of)

2016-10-15

Dissimilar metal weld (DMW), consisting of Alloy 600, Alloy 182, and A508 Gr.3, has been widely used as a joining material of the reactor pressure vessel penetration nozzle and the steam generator tubing for pressurized water reactors (PWR) because of its good mechanical strength, thermal conductivity, and corrosion resistance. Residual tensile stress is mainly nominated as a cause of SCC in light water reactors by IAEA report. So, to relax the residual stress, post-weld heat treatment is required after manufacturing process such as welding. However, thermal treatment has a great effect on the microstructure and the chromium depletion profile on Alloy 600, so called sensitization. By this reason, HAZ on Alloy 600 is critical to crack. According to G.A. Young et al., Crack growth rates (CGR) in the Alloy 600 HAZ were about 30 times faster than those in the Alloy 600 base metal tested under the same conditions. And according to Z.P. Lu et al., CGR in the Alloy 600 HAZ can be more than 20 times higher than that in its base metal. There are some methods to measure the exact value of residual stress on the material surface. The most common way is X-ray diffraction method (XRD). The principle of XRD is based on lattice strains and depends on the changes in the spacing of the atomic planes in material. And there is a computer simulation method to estimate residual stress distribution which is called ANSYS. This study was conducted to investigate how thermal aging affects residual stress and residual strain distribution of Alloy 600 HAZ. Following conclusions can be drawn from this study. According to preceding researches and this study, both the relaxation of residual stress and the change of residual strain follow as similar way, spreading out from concentrated region. The result of Vickers micro-hardness tester shows that tensile residual stresses are distributed broadly on the material aged by 15 years. Therefore, HT400{sub Y}15 material is weakest state for PWSCC. The

A new chiral residue analysis method for triazole fungicides in water using dispersive liquid-liquid microextraction (DLLME).

Science.gov (United States)

Luo, Mai; Liu, Donghui; Zhou, Zhiqiang; Wang, Peng

2013-09-01

A rapid, simple, reliable, and environment-friendly method for the residue analysis of the enantiomers of four chiral fungicides including hexaconazole, triadimefon, tebuconazole, and penconazole in water samples was developed by dispersive liquid-liquid microextraction (DLLME) pretreatment followed by chiral high-performance liquid chromatography (HPLC)-DAD detection. The enantiomers were separated on a Chiralpak IC column by HPLC applying n-hexane or petroleum ether as mobile phase and ethanol or isopropanol as modifier. The influences of mobile phase composition and temperature on the resolution were investigated and most of the enantiomers could be completely separated in 20 min under optimized conditions. The thermodynamic parameters indicated that the separation was enthalpy-driven. The elution orders were detected by both circular dichroism detector (CD) and optical rotatory dispersion detector (ORD). Parameters affecting the DLLME performance for pretreatment of the chiral fungicides residue in water samples, such as the extraction and dispersive solvents and their volume, were studied and optimized. Under the optimum microextraction condition the enrichment factors were over 121 and the linearities were 30-1500 µg L(-1) with the correlation coefficients (R(2)) over 0.9988 and the recoveries were between 88.7% and 103.7% at the spiking levels of 0.5, 0.25, and 0.05 mg L(-1) (for each enantiomer) with relative standard deviations varying from 1.38% to 6.70% (n = 6) The limits of detection (LODs) ranged from 8.5 to 29.0 µg L(-1) (S/N = 3). © 2013 Wiley Periodicals, Inc.

Addition of an organic amendment and/or residue mud to bauxite residue sand in order to improve its properties as a growth medium.

Science.gov (United States)

Jones, B E H; Haynes, R J; Phillips, I R

2012-03-01

The effects of addition of carbonated residue mud (RMC) or seawater neutralized residue mud (RMS), at two rates, in the presence or absence of added green waste compost, on the chemical, physical and microbial properties of gypsum-treated bauxite residue sand were studied in a laboratory incubation study. The growth of two species commonly used in revegetation of residue sand (Lolium rigidum and Acacia saligna) in the treatments was then studied in a 18-week greenhouse study. Addition of green waste-based compost increased ammonium acetate-extractable (exchangeable) Mg, K and Na. Addition of residue mud at 5 and 10% w/w reduced exchangeable Ca but increased that of Mg and Na (and K for RMS). Concentrations of K, Na, Mg and level of EC in saturation paste extracts were increased by residue mud additions. Concentrations of cations in water extracts were considerably higher than those in saturation paste extracts but trends with treatment were broadly similar. Addition of both compost and residue mud caused a significant decrease in macroporosity with a concomitant increase in mesoporosity and microporosity, available water holding capacity and the quantity of water held at field capacity. Increasing rates of added residue mud reduced the percentage of sample present as discrete sand particles and increased that in aggregated form (particularly in the 1-2 and >10mm diameter ranges). Organic C content, C/N ratio, soluble organic C, microbial biomass C and basal respiration were increased by compost additions. Where compost was added, residue mud additions caused a substantial increase in microbial biomass and basal respiration. L. rigidum grew satisfactorily in all treatments although yields tended to be reduced by additions of mud (especially RMC) particularly in the absence of added compost. Growth of A. saligna was poor in sand alone and mud-amended sand and was greatly promoted by additions of compost. However, in the presence of compost, addition of carbonated

Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

Science.gov (United States)

AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman

2014-02-01

Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) & 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) &29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of 232Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted.

Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

International Nuclear Information System (INIS)

AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman

2014-01-01

Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) and 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) and 29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of 232 Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted

Thorium, Uranium and Rare Earth Elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas Advanced Materials Plant (LAMP)

International Nuclear Information System (INIS)

Al-Areqi, W.M.; Amran Abdul Majid; Sukiman Sarmani

2013-01-01

Full-text: Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6 Bq/ kg) whereas the Th and U concentrations in WLP were determined to be 1952.9 ± 17.6 ppm (7987.4 ± 71.9 Bq/ kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/ kg) and 18.8 ppm and 1763.2 ppm (7211.4 Bq/ kg) and 29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of 232 Th compared to Malaysian soil natural background (63 - 110 Bq/ kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6 % and 4.7 ± 0.1 % respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04 %, 1.6 %, 0.22 % and 0.06 % respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be re

Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

Energy Technology Data Exchange (ETDEWEB)

AL-Areqi, Wadeeah M., E-mail: walareqi@yahoo.com; Majid, Amran Ab., E-mail: walareqi@yahoo.com; Sarmani, Sukiman, E-mail: walareqi@yahoo.com [Nuclear Science Programme, School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi (Malaysia)

2014-02-12

Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) and 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) and 29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of {sup 232}Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted.

Hazardous properties of paint residues from the furniture industry.

Science.gov (United States)

Vaajasaari, Kati; Kulovaara, Maaret; Joutti, Anneli; Schultz, Eija; Soljamo, Kari

2004-01-30

The objective of this study was to screen nine excess paint residues for environmental hazard and to evaluate their disposability in a non-hazardous or hazardous-waste landfill. These residues were produced in the process of spray-painting furniture. Residues were classified according to their leaching and ecotoxicological properties. Leaching properties were determined with the European standard SFS-EN 12457-2 leaching-test. The toxicity of the leaching-test eluates was measured with plant-, bacteria- and enzyme-inhibition bioassays. Total organic carbon, formaldehyde and solvent concentrations in the solid wastes and in the leaching-test eluates were analysed. It seemed likely that leached formaldehyde caused very high acute toxicity in leaching-test eluates of the dry-booth residues. This hypothesis was based on the fact that the formaldehyde concentrations in the leaching-test eluates of the dry-booth residues were 62-75 times higher than the EC50 value reported in the literature for formaldehyde. The results of the water-curtain booth residues showed that the samples with the highest TOC and aromatic solvent concentrations were also the most toxic. The studied excess paint residues were complex organic mixtures and contained large amounts of compounds not identifiable from chemical data. Therefore, the evaluation of the hazard based solely on available chemical data is unlikely to be sufficient, as evidenced by our study. Our results show that harmful compounds remain in the solid waste and the toxicity results of their leaching-test eluates show that toxicity may leach from residues in contact with water at landfill sites. They also confirm the benefit of combining chemical and ecotoxicological assays in assessing the potential environmental hazard of complex organic mixtures found in wastes. Copyright 2003 Elsevier B.V.

Climate change-induced water stress suppresses the regeneration of the critically endangered forest tree Nyssa yunnanensis.

Science.gov (United States)

Zhang, Shanshan; Kang, Hongmei; Yang, Wenzhong

2017-01-01

Climatic change-induced water stress has been found to threaten the viability of trees, especially endangered species, through inhibiting their recruitment. Nyssa yunnanensis, a plant species with extremely small populations (PSESP), consists of only two small populations of eight mature individuals remaining in southwestern China. In order to determine the barriers to regeneration, both in situ and laboratory experiments were performed to examine the critical factors hindering seed germination and seedling establishment. The results of in situ field experiments demonstrated that soil water potentials lower than -5.40 MPa (experienced in December) had significantly inhibitory effects on seedling survival, and all seedlings perished at a soil water potential of -5.60 MPa (January). Laboratory experiments verified that N. yunnanensis seedlings could not survive at a 20% PEG 6000 concentration (-5.34 MPa) or 1/5 water-holding capacity (WHC; -5.64 MPa), and seed germination was inhibited in the field from September (-1.10 MPa) to November (-4.30 MPa). Our results suggested that soil water potentials between -5.34 and -5.64 MPa constituted the range of soil water potentials in which N. yunnanensis seedlings could not survive. In addition to water deficit, intensified autotoxicity, which is concentration-dependent, resulted in lower seed germination and seedling survival. Thus, seed establishment was probably simultaneously impacted by water deficit and aggravated autotoxicity. Meteorological records from the natural distribution areas of N. yunnanensis indicated that mean annual rainfall and relative humidity have declined by 21.7% and 6.3% respectively over past 55 years, while the temperature has increased by 6.0%. Climate change-induced drought, along with a poor resistance and adaptability to drought stress, has severely impacted the natural regeneration of N. yunnanensis. In conclusion, climate change-induced drought has been implicated as a regulating factor in

Long-Term Effects of Residual Chlorine on Pseudomonas aeruginosa in Simulated Drinking Water Fed With Low AOC Medium

Directory of Open Access Journals (Sweden)

Guannan Mao

2018-05-01

Full Text Available Residual chlorine is often required to remain present in public drinking water supplies during distribution to ensure water quality. It is essential to understand how bacteria respond to long-term chlorine exposure, especially with the presence of assimilable organic carbon (AOC. This study aimed to investigate the effects of chlorination on Pseudomonas aeruginosa in low AOC medium by both conventional plating and culture-independent methods including flow cytometry (FCM and quantitative PCR (qPCR. In a simulated chlorinated system using a bioreactor, membrane damage and DNA damage were measured by FCM fluorescence fingerprint. The results indicated membrane permeability occurred prior to DNA damage in response to chlorination. A regrowth of P. aeruginosa was observed when the free chlorine concentration was below 0.3 mg/L. The bacterial response to long-term exposure to a constant low level of free chlorine (0.3 mg/L was subsequently studied in detail. Both FCM and qPCR data showed a substantial reduction during initial exposure (0–16 h, followed by a plateau where the cell concentration remained stable (16–76 h, until finally all bacteria were inactivated with subsequent continuous chlorine exposure (76–124 h. The results showed three-stage inactivation kinetics for P. aeruginosa at a low chlorine level with extended exposure time: an initial fast inactivation stage, a relatively stable middle stage, and a final stage with a slower rate than the initial stage. A series of antibiotic resistance tests suggested long-term exposure to low chlorine level led to the selection of antibiotic-resistant P. aeruginosa. The combined results suggest that depletion of residual chlorine in low AOC medium systems could reactivate P. aeruginosa, leading to a possible threat to drinking water safety.

Evaluation of Suppressiveness of Soils Exhibiting Soil-Borne Disease Suppression after Long-Term Application of Organic Amendments by the Co-cultivation Method of Pathogenic Fusarium oxysporum and Indigenous Soil Microorganisms.

Science.gov (United States)

Mitsuboshi, Masahiro; Kioka, Yuuzou; Noguchi, Katsunori; Asakawa, Susumu

2018-03-29

Preventive measures against soil-borne diseases need to be implemented before cultivation because very few countermeasures are available after the development of diseases. Some soils suppress soil-borne diseases despite the presence of a high population density of pathogens. If the suppressiveness of soil against soil-borne diseases may be predicted and diagnosed for crop fields, it may be possible to reduce the labor and cost associated with excessive disinfection practices. We herein evaluated the suppressiveness of soils in fields with the long-term application of organic amendments by examining the growth of pathogenic Fusarium oxysporum co-cultivated with indigenous soil microorganisms on agar plates. Soils treated with coffee residue compost or rapeseed meal showed suppressiveness against spinach wilt disease by F. oxysporum f. sp. spinaciae or spinach wilt and lettuce root rot diseases by F. oxysporum f. sp. spinaciae and F. oxysporum f. sp. lactucae, respectively, and the growth of pathogenic Fusarium spp. on agar plates was suppressed when co-cultured with microorganisms in a suspension from these soils before crop cultivation. These results indicate the potential of the growth degree of pathogenic F. oxysporum estimated by this method as a diagnostic indicator of the suppressiveness of soil associated with the inhabiting microorganisms. A correlation was found between the incidence of spinach wilt disease in spinach and the growth degree of F. oxysporum f. sp. spinaciae by this co-cultivation method, indicating that suppressiveness induced by organic amendment applications against F. oxysporum f. sp. spinaciae is evaluable by this method. The co-cultivation method may be useful for predicting and diagnosing suppressiveness against soil-borne diseases.

Determination of ethephon residues in water by gas chromatography with cubic mass spectrometry after ion-exchange purification and derivatisation with N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide.

Science.gov (United States)

Royer, A; Laporte, F; Bouchonnet, S; Communal, P-Y

2006-03-03

An analytical method has been developed for the determination of residues of ethephon (2-chloroethyl phosphonic acid) in drinking and surface water. The procedure is based on de-ionisation with an anion/cation-exchange resin, solid phase extraction by means of anion-exchange polystyrene-divinylbenzene extraction disks, elution with a mixture of methanol and 10 M hydrochloric acid (98/2, v/v), redisolution into acetonitrile after evaporation and silylation with N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA). Quantification is performed by gas chromatography with ion-trap cubic mass spectrometric detection in the electron impact mode (GC-EI-MS3). Method validation was conducted using samples of mineral, tap, and river water that were fortified with ethephon at concentration levels ranging from 0.1 to 1.0 microg/L. The mean recovery from all the fortified samples (n = 36) amounted to 88% with a relative standard deviation of 17%. The method, therefore, was shown to allow accurate determination of ethephon residues in drinking and surface water with a limit of quantification of 0.1 microg/L.

Near-source noise suppression of AMT by compressive sensing and mathematical morphology filtering

Science.gov (United States)

Li, Guang; Xiao, Xiao; Tang, Jing-Tian; Li, Jin; Zhu, Hui-Jie; Zhou, Cong; Yan, Fa-Bao

2017-12-01

In deep mineral exploration, the acquisition of audio magnetotelluric (AMT) data is severely affected by ambient noise near the observation sites; This near-field noise restricts investigation depths. Mathematical morphological filtering (MMF) proved effective in suppressing large-scale strong and variably shaped noise, typically low-frequency noise, but can not deal with pulse noise of AMT data. We combine compressive sensing and MMF. First, we use MMF to suppress the large-scale strong ambient noise; second, we use the improved orthogonal match pursuit (IOMP) algorithm to remove the residual pulse noise. To remove the noise and protect the useful AMT signal, a redundant dictionary that matches with spikes and is insensitive to the useful signal is designed. Synthetic and field data from the Luzong field suggest that the proposed method suppresses the near-source noise and preserves the signal well; thus, better results are obtained that improve the output of either MMF or IOMP.

Residual stress analysis in reactor pressure vessel attachments

International Nuclear Information System (INIS)

Dexter, R.J.; Pont, D.

1991-08-01

Residual stresses in cladding and welded attachments could contribute to the problem of stress-corrosion cracking in boiling-water reactors (BWR). As part of a larger program aimed at quantifying residual stress in BWR components, models that would be applicable for predicting residual stress in BWR components are reviewed and documented. The review includes simple methods of estimating residual stresses as well as advanced finite-element software. In general, simple methods are capable of predicting peak magnitudes of residual stresses but are incapable of adequately characterizing the distribution of residual stresses. Ten groups of researchers using finite-element software are reviewed in detail. For each group, the assumptions of the model, possible simplifications, material property data, and specific applications are discussed. The most accurate results are obtained when a metallurgical simulation is performed, transformation plasticity effects are included, and the heating and cooling parts of the welding thermal cycle are simulated. Two models are identified which can provide these features. The present state of these models and the material property data available in the literature are adequate to quantify residual stress in BWR components

'Water Structure' versus 'Radical Scavenger' theories as explanations for the suppressive effects of DMSO and related compounds on radiation-induced transformation in vitro

International Nuclear Information System (INIS)

Kennedy, A.R.; Symons, M.C.R.

1987-01-01

We report here that dimethylsulfoxide (DMSO): (i) suppresses radiation-induced transformation in vitro, even when DMSO treatments begin as late as 10 days post-irradiation; (ii) inhibits the 12-O-tetradecanoylphorbol-13-acetate (TPA) enhancement of radiation-induced transformation in vitro; (iii) does not affect the expression of transformed cells as foci (when surrounded by non-transformed cells); and (iv) may be affecting radiation-induced transformation through its solvent properties (i.e. the 'Water Structure' theory), while its effects on the TPA enhancement of radiation transformation may be mediated by its free radical scavenging abilities. DMSO, dimethylformamide (DMF) and dimethylacetamide (DMA) are similar solvents which are all very effective in their ability to suppress radiation-induced transformation in vitro. As DMSO is known to be an extremely effective OH free-radical scavenging agent, while DMF and DMA are not as efficient at scavenging free radicals, our results suggest that properties other than free-radical scavenging ability may be important in the suppressive effects of these compounds on radiation-induced transformation in vitro. (author)

Smoke suppression properties of ferrite yellow on flame retardant thermoplastic polyurethane based on ammonium polyphosphate

International Nuclear Information System (INIS)

Chen, Xilei; Jiang, Yufeng; Jiao, Chuanmei

2014-01-01

Highlights: • Smoke suppression of FeOOH on flame retardant TPU composites has been investigated. • FeOOH has excellent smoke suppression abilities for flame retardant TPU composites. • FeOOH has good ability of char formation, hence improved smoke suppression property. -- Abstract: This article mainly studies smoke suppression properties and synergistic flame retardant effect of ferrite yellow (FeOOH) on flame retardant thermoplastic polyurethane (TPU) composites using ammonium polyphosphate (APP) as a flame retardant agent. Smoke suppression properties and synergistic flame retardant effect of FeOOH on flame retardant TPU composites were intensively investigated by smoke density test (SDT), cone calorimeter test (CCT), scanning electron microscopy (SEM), and thermal-gravimetric analysis (TGA). Remarkably, the SDT results show that FeOOH can effectively decrease the amount of smoke production with or without flame. On the other hand, the CCT data reveal that the addition of FeOOH can apparently reduce heat release rate (HRR), total heat release (THR), and total smoke release (TSR), etc. Here, FeOOH is considered to be an effective smoke suppression agent and a good synergism with APP in flame retardant TPU composites, which can greatly improve the structure of char residue realized by TGA and SEM results

The inertial damping of the VIRGO superattenuator and the residual motion of the mirror

Energy Technology Data Exchange (ETDEWEB)

Losurdo, Giovanni [Istituto Nazionale di Fisica Nucleare - Sezione di Firenze, Lgo E Fermi, 2, Florence (Italy)

2002-04-07

The VIRGO superattenuator (SA) is effective in suppressing seismic noise below the expected thermal noise level above 4 Hz. However, the residual mirror motion associated with the SA normal modes can saturate the interferometer control system. This motion is reduced by implementing a wideband (DC-5 Hz) multidimensional active control (the so-called inertial damping) which makes use of both accelerometers and position sensors and of a digital signal processing (DSP) system. Feedback forces are exerted by coil-magnet actuators on the top of an inverted pendulum pre-isolator stage. The residual root mean square motion of the mirror in 10 s is less than 0.1 {mu}m.

MORTAR WITH UNSERVICEABLE TIRE RESIDUES

Directory of Open Access Journals (Sweden)

J. A. Canova

2009-01-01

Full Text Available This study analyzes the effects of unserviceable tire residues on rendering mortar using lime and washed sand at a volumetric proportion of 1:6. The ripened composite was dried in an oven and combined with both cement at a volumetric proportion of 1:1.5:9 and rubber powder in proportional aggregate volumes of 6, 8, 10, and 12%. Water exudation was evaluated in the plastic state. Water absorption by capillarity, fresh shrinkage and mass loss, restrained shrinkage and mass loss, void content, flexural strength, and deformation energy under compression were evaluated in the hardened state. There was an improvement in the water exudation and water absorption by capillarity and drying shrinkage, as well as a reduction of the void content and flexural strength. The product studied significantly aided the water exudation from mortar and, capillary elevation in rendering.

MORTAR WITH UNSERVICEABLE TIRE RESIDUES

Directory of Open Access Journals (Sweden)

José Aparecido Canova

2009-12-01

Full Text Available This study analyzes the effects of unserviceable tire residues on rendering mortar using lime and washed sand at a volumetric proportion of 1:6. The ripened composite was dried in an oven and combined with both cement at a volumetric proportion of 1:1.5:9 and rubber powder in proportional aggregate volumes of 6, 8, 10, and 12%. Water exudation was evaluated in the plastic state. Water absorption by capillarity, fresh shrinkage and mass loss, restrained shrinkage and mass loss, void content, flexural strength, and deformation energy under compression were evaluated in the hardened state. There was an improvement in the water exudation and water absorption by capillarity and drying shrinkage, as well as a reduction of the void content and flexural strength. The product studied significantly aided the water exudation from mortar and, capillary elevation in rendering.

The use of Lemna Minor (duckweed) to control the water quality in relation to coal residues. Gebruik van eendekroos voor het bewaken van de waterkwaliteit in relatie met kolenreststoffen

Energy Technology Data Exchange (ETDEWEB)

Janssen-Mommen, J P.M.; Jenner, H A [KEMA Milieu Services, Arnhem (Netherlands)

1993-01-01

Lemna Minor can be applied as a phytomonitor in a standardized test for ecotoxicological investigations of leachate extracts of coal residues and (water)soils. A standardized test method has been developed for fortnight toxicity experiments. The toxicity and the uptake of individual elements were studied in accumulation experiments.Special attention is paid to the impact of the factors complexation, interaction and speciation on the biological availability of the elements. Coal residues and water soils are leached and the leachate extracts are tested for growth restraint by means of the test method. It appears that the use of duckweed as a phytomonitor is a technically simple and reliable method

Magnitude of [14C] DDT residues in stored dried fish and pre-cooking processing effect on their removal

International Nuclear Information System (INIS)

Rahman, M.; Khatoon, J.; Matin, M.A.; Main, A.J.

1998-01-01

Residues of 14 C-DDT in stored dried fish was determined under ambient conditions for a 6 month period. Immediately after treatment, about 40% of the applied DDT was eliminated from surface of the dried fish with water washing. However, such removal was reduced to about 26% on storage for 6 months. Boiling of dried fish in water resulted in further removal of about 16% residues. In boiled dried fish, about 14% residues might remain and this could be removed by Soxhlet extraction. Surface extraction with hexane yielded about 80% of the residues immediately after treatment and the extractable residues decreased to about half the initial value of 6 months' storage. Dried fish residues, on surface extraction with water or hexane, when subjected to exhaustive Soxhlet extraction with methanol was found to result in further recovery of about 39-49% and 17-32%, respectively. Bound DDT residues were found to be about 5% in water washed dried fish samples and about 1.5% in case of hexane-extracted samples. Degradation of parent DDT to DDE and DDD was found. Maximum values of 16.58% DDE and 21.6% DDD were found in dried fish stored for 6 months. (author)

Contaminant Leach Testing of Hanford Tank 241-C-104 Residual Waste

Energy Technology Data Exchange (ETDEWEB)

Cantrell, Kirk J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M.V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-07-01

Leach testing of Tank C-104 residual waste was completed using batch and column experiments. Tank C-104 residual waste contains exceptionally high concentrations of uranium (i.e., as high as 115 mg/g or 11.5 wt.%). This study was conducted to provide data to develop contaminant release models for Tank C-104 residual waste and Tank C-104 residual waste that has been treated with lime to transform uranium in the waste to a highly insoluble calcium uranate (CaUO4) or similar phase. Three column leaching cases were investigated. In the first case, C-104 residual waste was leached with deionized water. In the second case, crushed grout was added to the column so that deionized water contacted the grout prior to contacting the waste. In the third case, lime was mixed in with the grout. Results of the column experiments demonstrate that addition of lime dramatically reduces the leachability of uranium from Tank C-104 residual waste. Initial indications suggest that CaUO4 or a similar highly insoluble calcium rich uranium phase forms as a result of the lime addition. Additional work is needed to definitively identify the uranium phases that occur in the as received waste and the waste after the lime treatment.

Residual stresses and stress corrosion cracking in pipe fittings

International Nuclear Information System (INIS)

Parrington, R.J.; Scott, J.J.; Torres, F.

1994-06-01

Residual stresses can play a key role in the SCC performance of susceptible materials in PWR primary water applications. Residual stresses are stresses stored within the metal that develop during deformation and persist in the absence of external forces or temperature gradients. Sources of residual stresses in pipe fittings include fabrication processes, installation and welding. There are a number of methods to characterize the magnitude and orientation of residual stresses. These include numerical analysis, chemical cracking tests, and measurement (e.g., X-ray diffraction, neutron diffraction, strain gage/hole drilling, strain gage/trepanning, strain gage/section and layer removal, and acoustics). This paper presents 400 C steam SCC test results demonstrating that residual stresses in as-fabricated Alloy 600 pipe fittings are sufficient to induce SCC. Residual stresses present in as-fabricated pipe fittings are characterized by chemical cracking tests (stainless steel fittings tested in boiling magnesium chloride solution) and by the sectioning and layer removal (SLR) technique

Reduced herbicide doses in combination with allelopathic plant extracts suppress weeds in wheat

International Nuclear Information System (INIS)

Afridi, R.A.; Khan, M.A.

2014-01-01

Allelopathy is gaining popularity worldwide probably for decreasing the cost of production and environment friendly weed suppressing approach. Repeated field studies conducted during 2011-12 and 2012-13 at Agricutural Research Institute Tarnab, Peshawar, Pakistan where allelopathic water extracts of Oryza sativa, Parthenium hysterophorus, Phragmites australis and Datura alba along with reduced doses of phenoxaprop-p-ethyl and bromoxinil+MCPA were tested for controlling weeds in wheat. It was observed that weed density was encouragly suppressed whereas spike length (cm), number of spikelets spike-1 and 1000 grain weight (g) of the wheat were improved when the allelopathic plant water extracts were used in combination with lower doses of herbicides. Thus, allelochemicals provide weed suppressing option in wheat. However, more studies are required to fully explore the possibility of weed management and isolation of the chemicals involved in weed suppression for environment friendly weed management in wheat. Such studies may decrease the cost of crop production and total use of herbicides. (author)

Coastal tomographic mapping of nonlinear tidal currents and residual currents

Science.gov (United States)

Zhu, Ze-Nan; Zhu, Xiao-Hua; Guo, Xinyu

2017-07-01

Depth-averaged current data, which were obtained by coastal acoustic tomography (CAT) July 12-13, 2009 in Zhitouyang Bay on the western side of the East China Sea, are used to estimate the semidiurnal tidal current (M2) as well as its first two overtide currents (M4 and M6). Spatial mean amplitude ratios M2:M4:M6 in the bay are 1.00:0.15:0.11. The shallow-water equations are used to analyze the generation mechanisms of M4 and M6. In the deep area, where water depths are larger than 60 m, M4 velocity amplitudes measured by CAT agree well with those predicted by the advection terms in the shallow water equations, indicating that M4 in the deep area is predominantly generated by the advection terms. M6 measured by CAT and M6 predicted by the nonlinear quadratic bottom friction terms agree well in the area where water depths are less than 20 m, indicating that friction mechanisms are predominant for generating M6 in the shallow area. In addition, dynamic analysis of the residual currents using the tidally averaged momentum equation shows that spatial mean values of the horizontal pressure gradient due to residual sea level and of the advection of residual currents together contribute about 75% of the spatial mean values of the advection by the tidal currents, indicating that residual currents in this bay are induced mainly by the nonlinear effects of tidal currents. This is the first ever nonlinear tidal current study by CAT.

Relationships between residue Voronoi volume and sequence conservation in proteins.

Science.gov (United States)

Liu, Jen-Wei; Cheng, Chih-Wen; Lin, Yu-Feng; Chen, Shao-Yu; Hwang, Jenn-Kang; Yen, Shih-Chung

2018-02-01

Functional and biophysical constraints can cause different levels of sequence conservation in proteins. Previously, structural properties, e.g., relative solvent accessibility (RSA) and packing density of the weighted contact number (WCN), have been found to be related to protein sequence conservation (CS). The Voronoi volume has recently been recognized as a new structural property of the local protein structural environment reflecting CS. However, for surface residues, it is sensitive to water molecules surrounding the protein structure. Herein, we present a simple structural determinant termed the relative space of Voronoi volume (RSV); it uses the Voronoi volume and the van der Waals volume of particular residues to quantify the local structural environment. RSV (range, 0-1) is defined as (Voronoi volume-van der Waals volume)/Voronoi volume of the target residue. The concept of RSV describes the extent of available space for every protein residue. RSV and Voronoi profiles with and without water molecules (RSVw, RSV, VOw, and VO) were compared for 554 non-homologous proteins. RSV (without water) showed better Pearson's correlations with CS than did RSVw, VO, or VOw values. The mean correlation coefficient between RSV and CS was 0.51, which is comparable to the correlation between RSA and CS (0.49) and that between WCN and CS (0.56). RSV is a robust structural descriptor with and without water molecules and can quantitatively reflect evolutionary information in a single protein structure. Therefore, it may represent a practical structural determinant to study protein sequence, structure, and function relationships. Copyright © 2017 Elsevier B.V. All rights reserved.

Fe-Ti/Fe (II)-loading on ceramic filter materials for residual chlorine removal from drinking water.

Science.gov (United States)

Man, Kexin; Zhu, Qi; Guo, Zheng; Xing, Zipeng

2018-06-01

Ceramic filter material was prepared with silicon dioxide (SiO 2 ), which was recovered from red mud and then modified with Fe (II) and Fe-Ti bimetal oxide. Ceramic filter material can be used to reduce the content of residual chlorine from drinking water. The results showed that after a two-step leaching process with 3 M hydrochloric acid (HCl) and 90% sulfuric acid (H 2 SO 4 ), the recovery of SiO 2 exceeded 80%. Fe (II)/Fe-Ti bimetal oxide, with a high adsorption capacity of residual chlorine, was prepared using a 3:1 M ratio of Fe/Ti and a concentration of 0.4 mol/L Fe 2+ . According to the zeta-potential, scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis, Fe (II) and Fe-Ti bimetal oxide altered the zeta potential and structural properties of the ceramic filter material. There was a synergistic interaction between Fe and Ti in which FeOTi bonds on the material surface and hydroxyl groups provided the active sites for adsorption. Through a redox reaction, Fe (II) transfers hypochlorite to chloride, and FeOTiCl bonds were formed after adsorption. Copyright © 2018 Elsevier Ltd. All rights reserved.

SU-E-J-243: Possibility of Exposure Dose Reduction of Cone-Beam Computed Tomography in An Image Guided Patient Positioning System by Using Various Noise Suppression Filters

International Nuclear Information System (INIS)

Kamezawa, H; Arimura, H; Ohki, M; Shirieda, K; Kameda, N

2014-01-01

Purpose: To investigate the possibility of exposure dose reduction of the cone-beam computed tomography (CBCT) in an image guided patient positioning system by using 6 noise suppression filters. Methods: First, a reference dose (RD) and low-dose (LD)-CBCT (X-ray volume imaging system, Elekta Co.) images were acquired with a reference dose of 86.2 mGy (weighted CT dose index: CTDIw) and various low doses of 1.4 to 43.1 mGy, respectively. Second, an automated rigid registration for three axes was performed for estimating setup errors between a planning CT image and the LD-CBCT images, which were processed by 6 noise suppression filters, i.e., averaging filter (AF), median filter (MF), Gaussian filter (GF), bilateral filter (BF), edge preserving smoothing filter (EPF) and adaptive partial median filter (AMF). Third, residual errors representing the patient positioning accuracy were calculated as an Euclidean distance between the setup error vectors estimated using the LD-CBCT image and RD-CBCT image. Finally, the relationships between the residual error and CTDIw were obtained for 6 noise suppression filters, and then the CTDIw for LD-CBCT images processed by the noise suppression filters were measured at the same residual error, which was obtained with the RD-CBCT. This approach was applied to an anthropomorphic pelvic phantom and two cancer patients. Results: For the phantom, the exposure dose could be reduced from 61% (GF) to 78% (AMF) by applying the noise suppression filters to the CBCT images. The exposure dose in a prostate cancer case could be reduced from 8% (AF) to 61% (AMF), and the exposure dose in a lung cancer case could be reduced from 9% (AF) to 37% (AMF). Conclusion: Using noise suppression filters, particularly an adaptive partial median filter, could be feasible to decrease the additional exposure dose to patients in image guided patient positioning systems

SU-E-J-243: Possibility of Exposure Dose Reduction of Cone-Beam Computed Tomography in An Image Guided Patient Positioning System by Using Various Noise Suppression Filters

Energy Technology Data Exchange (ETDEWEB)

Kamezawa, H [Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka (Japan); Fujimoto General Hospital, Miyakonojo, Miyazaki (Japan); Arimura, H; Ohki, M [Faculty of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka (Japan); Shirieda, K; Kameda, N [Fujimoto General Hospital, Miyakonojo, Miyazaki (Japan)

2014-06-01

Purpose: To investigate the possibility of exposure dose reduction of the cone-beam computed tomography (CBCT) in an image guided patient positioning system by using 6 noise suppression filters. Methods: First, a reference dose (RD) and low-dose (LD)-CBCT (X-ray volume imaging system, Elekta Co.) images were acquired with a reference dose of 86.2 mGy (weighted CT dose index: CTDIw) and various low doses of 1.4 to 43.1 mGy, respectively. Second, an automated rigid registration for three axes was performed for estimating setup errors between a planning CT image and the LD-CBCT images, which were processed by 6 noise suppression filters, i.e., averaging filter (AF), median filter (MF), Gaussian filter (GF), bilateral filter (BF), edge preserving smoothing filter (EPF) and adaptive partial median filter (AMF). Third, residual errors representing the patient positioning accuracy were calculated as an Euclidean distance between the setup error vectors estimated using the LD-CBCT image and RD-CBCT image. Finally, the relationships between the residual error and CTDIw were obtained for 6 noise suppression filters, and then the CTDIw for LD-CBCT images processed by the noise suppression filters were measured at the same residual error, which was obtained with the RD-CBCT. This approach was applied to an anthropomorphic pelvic phantom and two cancer patients. Results: For the phantom, the exposure dose could be reduced from 61% (GF) to 78% (AMF) by applying the noise suppression filters to the CBCT images. The exposure dose in a prostate cancer case could be reduced from 8% (AF) to 61% (AMF), and the exposure dose in a lung cancer case could be reduced from 9% (AF) to 37% (AMF). Conclusion: Using noise suppression filters, particularly an adaptive partial median filter, could be feasible to decrease the additional exposure dose to patients in image guided patient positioning systems.

Dynamics, Residue and Risk Assessment of Nitenpyram in Rice and Paddy Field

Directory of Open Access Journals (Sweden)

YUAN Xue-xia

2016-09-01

Full Text Available Residues dynamics, final residual levels and dietary intake risk of nitenpyram in rice and paddy field were investigated in three dif-ferent regions of China(Shandong, Henan and Anhui. A method was illustrated to detect nitenpyram residues in paddy, plant, brown rice, paddy water and soil. The residues in paddy and rice were extracted with methanol+phosphate buffer(0.2 mol·L-1, pH=7.0(60+40, adjust pH to 2.5, then cleaned up with solid phase extraction column and 0.22 μm filter membrane, and then analyzed by HPLC with an ul-traviolet detector at 260 nm. When spiked 0.05, 0.5, 1.0 mg·kg-1, the recoveries of nitenpyram in paddy plant and brown rice were 78.4%~94.7% and 84.0%~94.2%, respectively. The residues in paddy water and soil were extracted with phosphate buffer (0.2 mol·L-1, pH=7.0, when spiked 0.01, 0.5, 1.0 mg·kg-1, the recoveries of nitenpyram in paddy water and soil were 84.6%~98.0% and 93.7%~97.1%, respective-ly, which indicated this method match the requirement of the detection. Two years results showed that nitenpyram belongs to easily degraded pesticides, because all half-lives were below 1.4 d in rice plant, as well as below 4.2 d in paddy water. Final residual levels of nitenpyram in rice were all below 0.05 mg·kg-1,which was far below the Japanese maximum residue limit(0.5 mg·kg-1. The risk quotients (RQs were low for different populations in China, which indicated its low risk in rice. Therefore, the rice with nitenpyram applied, according to the recom-mend method, 45 g·hm-2 application once, with 21 days collection interval, was safe.

Quantification of heavy metals from residual waste and ashes from the treatment plant of residual water Reciclagua and,effects for the health of those workers which manipulate those residuals; Cuantificacion de metales pesados de lodo residual y cenizas de la planta tratadora de aguas residuales Reciclagua y efectos a la salud de los trabajadores que manipulan los residuos

Energy Technology Data Exchange (ETDEWEB)

Guerrero D, J.J

2004-07-01

In this work, the technique of leaching using thermostatted column in series is applied, the X-ray diffraction for the identification of the atomic and molecular structure of the toxic metals that are present in the residual muds of the water treatment plant located in the municipality of Lerma Estado de Mexico, named RECICLAGUA, likewise the technique is used of emission spectrometry for plasma and X-ray fluorescence for the qualitative analysis. Its were take samples of residual mud and of incinerated mud of the treatment plant of residual waters of the industrial corridor Toluca -Lerma RECICLAGUA, located in Lerma Estado de Mexico. For this study there were mixed 100 g of residual mud with a solution to 10% of mineral acid or sodium hydroxide according to the case, to adjust the one pH at 2, 5, 7 and 10, it was added bisulfite, of 0.3-1.5 g of dodecyl sulfate sodium and 3.939 of DTPA (triple V) (Diethylene triamine pentaacetate). To this mud and ashes were extracted the toxic and valuable metals by means of the leaching technique using thermostatted columns placed in series that were designed by the Dr. Jaime Vite Torres; it is necessary to make mention that so much the process as the equipment with those that work it was patented by the same one. With the extraction of these metals benefits are obtained, mainly of economic type, achieving the decrease of the volume of those wastes that have been generated; as well as the so much the use of those residuals, once the metals have been eliminated, as of those liquors where the metals were extracted. It was carried out a quantitative analysis using emission spectrometry by plasma in solids by this way to be able to know the content of the present metals in the sample before and later of leaching them, these results reported a great quantity of elements. Another of the techniques employees was the X-ray diffraction analysis that provides an elementary content of the samples, identifying elements that are present in

Ecotoxicological assessment of dewatered drinking water treatment residue for environmental recycling.

Science.gov (United States)

Yuan, Nannan; Wang, Changhui; Wendling, Laura A; Pei, Yuansheng

2017-09-01

The beneficial recycle of drinking water treatment residue (DWTR) in environmental remediation has been demonstrated in many reports. However, the lack of information concerning the potential toxicity of dewatered DWTR hinders its widespread use. The present study examined the ecotoxicity of dewatered aluminum (Al) and iron (Fe) DWTR leachates to a green alga, Chlorella vulgaris. Data from the variations of cell density and chlorophyll a content suggested that algal growth in DWTR leachates was inhibited. The algal cellular oxidation stress was initially induced but completely eliminated within 72 h by antioxidant enzymes. The expression of three photosynthesis-related algae genes (psaB, psbC, and rbcL) also temporarily decreased (within 72 h). Moreover, the algal cells showed intact cytomembranes after exposure to DWTR leachates. Further investigation confirmed that inhibition of algal growth was due to DWTR-induced phosphorus (P) deficiency in growth medium, rather than potentially toxic contaminants (e.g. copper and Al) contained in DWTR. Interestingly, the leachates could potentially promote algal growth via increasing the supply of new components (e.g. calcium, kalium, magnesium, and ammonia nitrogen) from DWTR. In summary, based on the algae toxicity test, the dewatered Fe/Al DWTR was nontoxic and its environment recycling does not represent an ecotoxicological risk to algae.

The Soil-Water Characteristic Curve of Unsaturated Tropical Residual Soil

Science.gov (United States)

Yusof, M. F.; Setapa, A. S.; Tajudin, S. A. A.; Madun, A.; Abidin, M. H. Z.; Marto, A.

2016-07-01

This study was conducted to determine the SWCC of unsaturated tropical residual soil in Kuala Lumpur, Malaysia. Undisturbed soil samples at five locations of high-risk slopes area were taken at a depth of 0.5 m using block sampler. In the determination of the SWCC, the pressure plate extractor with the capacity of 1500 kN/m2 has been used. The index properties of the soil such as natural moisture content, Atterberg limits, specific gravity, and soil classification are performed according to BS 1377: Part 2: 1990. The results of index properties show that the natural moisture content of the soil is between 36% to 46%, the plasticity index is between 10% - 26%, the specific gravity is between 2.51 - 2.61 and the soils is classified as silty organic clay of low plasticity. The SWCC data from the pressure plate extractor have been fitted with the Fredlund and Xing equation. The results show that the air entry value and residual matric suction for residual soils are in the range of 17 kN/m2 to 24 kN/m2 and 145 kN/m2 to 225 kN/m2 respectively. From the fitting curve, it is found that the average value of the Fredlund and Xing parameters such as a, n and m are in the range of 0.24-0.299, 1.7-4.8 and 0.142-0.440 respectively.

Qualidade química da água residual da criação de peixes para cultivo de alface em hidroponia Chemical quality of residual water from fish breeding tanks for cultivation of hydroponic lettuce

Directory of Open Access Journals (Sweden)

Glauco E. P. Cortez

2009-08-01

Full Text Available Com o objetivo de avaliar a associação do cultivo de alface em hidroponia com utilização dos resíduos do sistema de criação intensiva de peixe, desenvolveu-se um trabalho no Centro de Aqüicultura, na FCAV-UNESP, Campus de Jaboticabal, SP. A integração foi projetada para que a água circulasse de maneira fechada entre os sistemas, passando pelos tanques de criação de peixes, por um decantador, para remo��ão dos resíduos por um reservatório para conversão biológica da amônia em nitrato e pelo sistema hidropônico, retornando aos tanques de criação dos peixes. Foram avaliadas três cultivares de alface, que constituíram os tratamentos com quatro repetições. Os resultados da análise química da água residual da criação indicaram a presença da maioria dos nutrientes minerais necessários ao desenvolvimento vegetal, em concentração próxima aos valores encontrados em soluções nutritivas utilizadas para o cultivo da alface em hidroponia, exceto potássio e magnésio. A baixa concentração de magnésio na água não impediu o desenvolvimento da alface; entretanto, as plantas indicaram sintomas visuais de deficiência deste nutriente. Não houve diferenças entre as cultivares quanto à produtividade e ao peso fresco de plantas.Aiming to evaluate the association of hydroponic lettuce cultivation with residues from a fish intensive breeding system, a project was carried out in the Aquaculture Center in the FCAV-UNESP at Jaboticabal, SP, Brazil. A closed system was designed in order to allow the water to circulate through the fish tanks, a clarifier tank for removal of residues, a reservoir for biological conversion of ammonia into nitrate, and the hydroponic system. After this process, water returned back to the fish tanks. Three varieties of lettuce, constituting the treatments with four repetitions were evaluated. The results of the chemical analysis of the residual water from the fish tanks indicated the presence of

Cytotoxic effects of oxytetracycline residues in the bones of broiler chickens following therapeutic oral administration of a water formulation.

Science.gov (United States)

Odore, R; De Marco, M; Gasco, L; Rotolo, L; Meucci, V; Palatucci, A T; Rubino, V; Ruggiero, G; Canello, S; Guidetti, G; Centenaro, S; Quarantelli, A; Terrazzano, G; Schiavone, A

2015-08-01

Tetracyclines, which represent one of the most commonly used antibiotics for poultry, are known to be deposited in bones, where they can remain, despite the observation of appropriate withdrawal times. The aim of the study was to determine the concentration of oxytretracycline (OTC) residues in the bone and muscle of chickens, following the oral administration of a commercially available liquid formulation, and to test their cytotoxic effects on an in vitro cell culture model. Seventy-two 1-day-old broiler chickens were randomly allotted into 2 groups (control and treated animals). OTC (40 mg/kg BW) was administered via drinking water during the 1 to 5 and 20 to 25 days of life periods. At the end of the trial, the birds were slaughtered and the OTC residues in the target tissues were measured by means of liquid chromatography (LC) - tandem mass spectrometry (MS/MS). Cytotoxicity was assessed by evaluating the pro-apoptotic effect of the bone residues on the K562 erythroleukemic line and on the peripheral blood mononuclear cells (PBMC). In all the animals, the OTC residues in the muscle were far below the established MRL of 100 μg/kg. The OTC levels in the bones of the treated animals were instead found in the parts per million (ppm) range. Cell cytotoxicity was assessed by evaluating the pro-apoptotic effect of OTC bone residues on the haematopoietic cell system. This in vitro system has revealed a significant pro-apoptotic effect on both the K562 cell line and PBMC cultures. This result suggests potential human and animal health risks due to the entry of tetracycline residues contained in the bones of treated livestock into the food-chain. This could be of concern, particularly for canine and feline diets, as meat, bone meal, and poultry by-products represent some of the main ingredients of pet foods, especially in the case of dry pet food. Further studies are needed to define the underlying mechanisms of cytotoxicity and to evaluate the in vivo toxicological

The influence of the calibration standard and the chemical composition of the water samples residue in the counting efficiency of proportional detectors for gross alpha and beta counting. Application on the radiologic control of the IPEN-CNEN/SP

International Nuclear Information System (INIS)

Santos, Cecilia Martins

2003-01-01

In this work the efficiency calibration curves of thin-window and low background gas-flow proportional counters were determined for calibration standards with different energies and different absorber thicknesses. For the gross alpha counting we have used 241 Am and natural uranium standards and for the gross beta counting we have used 90 Sr/ 90 Y and 137 Cs standards in residue thicknesses ranging from 0 to approximately 18 mg/cm 2 . These sample thicknesses were increased with a previously determined salted solution prepared simulating the chemical composition of the underground water of IPEN The counting efficiency for alpha emitters ranged from 0,273 +- 0,038 for a weightless residue to only 0,015 +- 0,002 in a planchet containing 15 mg/cm 2 of residue for 241 Am standard. For natural uranium standard the efficiency ranged from 0,322 +- 0,030 for a weightless residue to 0,023 +- 0,003 in a planchet containing 14,5 mg/cm 2 of residue. The counting efficiency for beta emitters ranged from 0,430 +- 0,036 for a weightless residue to 0,247 +- 0,020 in a planchet containing 17 mg/cm 2 of residue for 137 Cs standard. For 90 Sr/ 90 Y standard the efficiency ranged from 0,489 +- 0,041 for a weightless residue to 0,323 +- 0,026 in a planchet containing 18 mg/cm 2 of residue. Results make evident the counting efficiency variation with the alpha or beta emitters energies and the thickness of the water samples residue. So, the calibration standard, the thickness and the chemical composition of the residue must always be considered in the gross alpha and beta radioactivity determination in water samples. (author)

Residual stress development and relief in high strength aluminium alloys using standard and retrogression thermal treatments

OpenAIRE

Robinson, J.S; Tanner, D.A

2003-01-01

peer-reviewed Residual stresses develop in the aluminium alloy 7010 when the material is quenched from the solution heat treatment temperature. Residual stress measurements have been made using the X-ray diffraction technique and a longitudinal split sawcut method to determine the magnitude of residual stress that develops in specimens sectioned from large open die forgings as a result of (a) quenching these specimens into water at different temperatures, and (b) cold water quenching from ...

Quadratic residues and non-residues selected topics

CERN Document Server

Wright, Steve

2016-01-01

This book offers an account of the classical theory of quadratic residues and non-residues with the goal of using that theory as a lens through which to view the development of some of the fundamental methods employed in modern elementary, algebraic, and analytic number theory. The first three chapters present some basic facts and the history of quadratic residues and non-residues and discuss various proofs of the Law of Quadratic Reciprosity in depth, with an emphasis on the six proofs that Gauss published. The remaining seven chapters explore some interesting applications of the Law of Quadratic Reciprocity, prove some results concerning the distribution and arithmetic structure of quadratic residues and non-residues, provide a detailed proof of Dirichlet’s Class-Number Formula, and discuss the question of whether quadratic residues are randomly distributed. The text is a valuable resource for graduate and advanced undergraduate students as well as for mathematicians interested in number theory.

Measurements of three dimensional residual stress distribution on laser irradiated spot

International Nuclear Information System (INIS)

Tanaka, Hirotomo; Akita, Koichi; Ohya, Shin-ichi; Sano, Yuji; Naito, Hideki

2004-01-01

Three dimensional residual stress distributions on laser irradiated spots were measured using synchrotron radiation to study the basic mechanism of laser peening. A water-immersed sample of high tensile strength steel was irradiated with Q-switched and frequency-doubled Nd:YAG laser. The residual stress depth profile of the sample was obtained by alternately repeating the measurement and surface layer removal by electrolytic polishing. Tensile residual stresses were observed on the surface of all irradiated spots, whereas residual stress changed to compressive just beneath the surface. The depth of compressive residual stress imparted by laser irradiation and plastic deformation zone increased with increasing the number of laser pulses irradiated on the same spot. (author)

Use of ultrasound in petroleum residue upgradation

Energy Technology Data Exchange (ETDEWEB)

Sawarkar, A.N.; Pandit, A.B.; Samant, S.D.; Joshi, J.B. [Mumbai Univ., Mumbai (India). Inst. of Chemical Technology

2009-06-15

The importance of bottom-of-the barrel upgrading has increased in the current petroleum refining scenario because of the progressively heavier nature of crude oil. Heavy residues contain large concentrations of metals such as vanadium and nickel which foul catalysts and reduce the potential effect of residue fluidized catalytic cracking. This study showed that the cavitational energy induced by ultrasound be be successfully used to upgrade hydrocarbon mixtures. Conventional processes for the upgrading of residual feedstocks, such as thermal cracking and catalytic cracking, were carried out in the temperature range of 400-520 degrees C. Experiments were performed on 2 vacuum residues, Arabian mix vacuum residue (AMVR) and Bombay high vacuum residue (BHVR) and 1 Haldia asphalt (HA). These were subjected to acoustic cavitation for different reaction times from 15 to 120 minutes at ambient temperature and pressure. Two acoustic cavitation devices were compared, namely the ultrasonic bath and ultrasonic horn. In particular, this study compared the ability of these 2 devices to upgrade the petroleum residues to lighter, more value-added products. Different surfactants were used to examine the effect of ultrasound on upgrading the residue when emulsified in water. In order to better understand the reaction mechanism, a kinetic model was developed based on the constituents of the residue. The ultrasonic horn was found to be more effective in bringing about the upgrading than ultrasonic bath. The study also showed that the acoustic cavitation of the aqueous emulsified hydrocarbon mixture could reduce the asphaltenes content to a greater extent than the acoustic cavitation of non-emulsified hydrocarbon mixture. 20 refs., 11 tabs., 17 figs.

Drying of residue and separation of nitrate salts in the sludge waste for the lagoon sludge treatment

International Nuclear Information System (INIS)

Hwang, D. S.; Lee, K. I.; Choi, Y. D.; Hwang, S. T.; Park, J. H.

2003-01-01

This study investigated the dissolution property of nitrate salts in the dissolution process by water and the drying property of residue after separating nitrates in a series of the processes for the sludge treatment. Desalination was carried out with the adding ratio of water and drying property was analyzed by TG/DTA, FTIR, and XRD. Nitrate salts involved in the sludge were separated over 97% at the water adding ratio of 2.5. But a small quantity of calcium and sodium nitrate remained in the residue These were decomposed over 600 .deg. C and calcium carbonate, which was consisted mainly of residue, was decomposed into calcium oxide over 750 .deg. C. The residue have to be decomposed over 800 .deg. C to converse uranyl nitrate of six value into the stable U 3 O 8 of four value. As a result of removing the nitrates at the water adding ratio of 2.5 and drying the residue over 900 .deg. C, volume of the sludge waste decreased over 80%

α-chymotrypsin in water-acetone and water-dimethyl sulfoxide mixtures: Effect of preferential solvation and hydration.

Science.gov (United States)

Sirotkin, Vladimir A; Kuchierskaya, Alexandra A

2017-10-01

We investigated water/organic solvent sorption and residual enzyme activity to simultaneously monitor preferential solvation/hydration of protein macromolecules in the entire range of water content at 25°C. We applied this approach to estimate protein destabilization/stabilization due to the preferential interactions of bovine pancreatic α-chymotrypsin with water-acetone (moderate-strength H-bond acceptor) and water-DMSO (strong H-bond acceptor) mixtures. There are three concentration regimes for the dried α-chymotrypsin. α-Chymotrypsin is preferentially hydrated at high water content. The residual enzyme activity values are close to 100%. At intermediate water content, the dehydrated α-chymotrypsin has a higher affinity for acetone/DMSO than for water. Residual enzyme activity is minimal in this concentration range. The acetone/DMSO molecules are preferentially excluded from the protein surface at the lowest water content, resulting in preferential hydration. The residual catalytic activity in the water-poor acetone is ∼80%, compared with that observed after incubation in pure water. This effect is very small for the water-poor DMSO. Two different schemes are operative for the hydrated enzyme. At high and intermediate water content, α-chymotrypsin exhibits preferential hydration. However, at intermediate water content, in contrast to the dried enzyme, the initially hydrated α-chymotrypsin possesses increased preferential hydration parameters. At low water content, no residual enzyme activity was observed. Preferential binding of DMSO/acetone to α-chymotrypsin was detected. Our data clearly demonstrate that the hydrogen bond accepting ability of organic solvents and the protein hydration level constitute key factors in determining the stability of protein-water-organic solvent systems. © 2017 Wiley Periodicals, Inc.

Residues of tritium-labeled morantel in lactating dairy cattle

International Nuclear Information System (INIS)

Lynch, M.J.; Mosher, F.R.; Burnett, D.M.; Newby, T.J.

1987-01-01

Residues of morantel and its metabolites were monitored in plasma, urine, and milk of five lactating dairy cattle that received an oral dose of [4,4-pyrimidyl- 3 H 2 ]morantel tartrate at 10 mg/kg. Drug-related radioactivity peaked in plasma at 8 h and in milk by the second milking, postdose, and was 170 and 84 ng/mL, respectively. The fraction of total residues in milk convertible to the marker compound, N-methyl-1,3-propanediamine, was 0.38 on the basis of a comparison of the areas under the curves for total and marker residues. Five days after dosing, 3.9% of the total radioactivity in liver was recovered as tritium water. Total drug-related residues in this target tissue averaged 1.15 μg/g. About half of the drug-related residues in liver was unextractable and was classified by bound

Comprehensive reuse of drinking water treatment residuals in coagulation and adsorption processes.

Science.gov (United States)

Jung, Kyung-Won; Hwang, Min-Jin; Park, Dae-Seon; Ahn, Kyu-Hong

2016-10-01

While drinking water treatment residuals (DWTRs) inevitably lead to serious problems due to their huge amount of generation and limitation of landfill sites, their unique properties of containing Al or Fe contents make it possible to reuse them as a beneficial material for coagulant recovery and adsorbent. Hence, in the present study, to comprehensively handle and recycle DWTRs, coagulant recovery from DWTRs and reuse of coagulant recovered residuals (CRs) were investigated. In the first step, coagulant recovery from DWTRs was conducted using response surface methodology (RSM) for statistical optimization of independent variables (pH, solid content, and reaction time) on response variable (Al recovery). As a result, a highly acceptable Al recovery of 97.5 ± 0.4% was recorded, which corresponds to 99.5% of the predicted Al recovery. Comparison study of recovered and commercial coagulant from textile wastewater treatment indicated that recovered coagulant has reasonable potential for use in wastewater treatment, in which the performance efficiencies were 68.5 ± 2.1% COD, 97.2 ± 1.9% turbidity, and 64.3 ± 1.0% color removals at 50 mg Al/L. Subsequently, in a similar manner, RSM was also applied to optimize coagulation conditions (Al dosage, initial pH, and reaction time) for the maximization of real cotton textile wastewater treatment in terms of COD, turbidity, and color removal. Overall performance revealed that the initial pH had a remarkable effect on the removal performance compared to the effects of other independent variables. This is mainly due to the transformation of metal species form with increasing or decreasing pH conditions. Finally, a feasibility test of CRs as adsorbent for phosphate adsorption from aqueous solution was conducted. Adsorption equilibrium of phosphate at different temperatures (10-30 °C) and initial levels of pH (3-11) indicated that the main mechanisms of phosphate adsorption onto CRs are endothermic and chemical

X-ray absorption spectroscopy as a tool investigating arsenic(III) and arsenic(V) sorption by an aluminum-based drinking-water treatment residual.

Science.gov (United States)

Makris, Konstantinos C; Sarkar, Dibyendu; Parsons, Jason G; Datta, Rupali; Gardea-Torresdey, Jorge L

2009-11-15

Historic applications of arsenical pesticides to agricultural land have resulted in accumulation of residual arsenic (As) in such soils. In situ immobilization represents a cost-effective and least ecological disrupting treatment technology for soil As. Earlier work in our laboratory showed that drinking-water treatment residuals (WTRs), a low-cost, waste by-product of the drinking-water treatment process exhibit a high affinity for As. Wet chemical experiments (sorption kinetics and desorption) were coupled with X-ray absorption spectroscopy measurements to elucidate the bonding strength and type of As(V) and As(III) sorption by an aluminum-based WTR. A fast (1h), followed by a slower sorption stage resulted in As(V) and As(III) sorption capacities of 96% and 77%, respectively. Arsenic desorption with a 5mM oxalate from the WTR was minimal, being always absorption spectroscopy data showed inner-sphere complexation between As and surface hydroxyls. Reaction time (up to 48h) had no effect on the initial As oxidation state for sorbed As(V) and As(III). A combination of inner-sphere bonding types occurred between As and Al on the WTR surface because mixed surface geometries and interatomic distances were observed.

The Calculation and Design of Fire suppression system in the proton accelerator research center

International Nuclear Information System (INIS)

Jeon, G. P.; Kim, J. Y.; Cho, J. H.; Min, Y. S.; Mun, K. J.; Cho, J. S.; Nam, J. M.; Park, S. S.; Joo, H. G.

2010-01-01

The fire protection system is composed of various fire suppression systems and fire detection and alarm systems. The primary function of the fire protection system is to protect life and property from a fire through detecting fires quickly and suppressing those fires that occur. In this paper, we described the fire suppression system only. The fire suppression system capacity for fire hydrant, the water mist system, sprinkler system and clean agent system is calculated and designed in compliance with the applicable Korean Acts that are applicable to fire protection and the NFSC code

Effects of a hypothetical loss-of-coolant accident on a Mark I Boiling Water Reactor pressure-suppression system

International Nuclear Information System (INIS)

Pitts, J.H.; McCauley, E.W.

1977-01-01

A loss-of-coolant accident (LOCA) in a boiling-water-reactor (BWR) power plant has never occurred. However, because this type of accident could be particularly severe, it is used as a principal theoretical basis for design. A series of consistent, versatile, and accurate air-water tests that simulate LOCA conditions has been completed on a 1 / 5 -scale Mark I BWR pressure-suppression system. Results from these tests are used to quantify the vertical-loading function and to study the associated fluid dynamics phenomena. Detailed histories of vertical loads on the wetwell are shown. In particular, variation of hydrodynamic-generated vertical loads with changes in drywell-pressurization rate, downcomer submergence, and the vent-line loss coefficient are established. Initial drywell overpressure, which partially preclears the downcomers of water, substantially reduces the peak vertical loads. Scaling relationships, developed from dimensional analysis and verified by bench-top experiments, allow the 1 / 5 -scale results to be applied to a full-scale BWR power plant. This analysis leads to dimensionless groupings that are invariant. These groupings show that, if water is used as the working fluid, the magnitude of the forces in a scaled facility is reduced by the cube of the scale factor and occurs in a time reduced by the square root of the scale factor

Calculating residual flows through a multiple-inlet system: the conundrum of the tidal period

Science.gov (United States)

Duran-Matute, Matias; Gerkema, Theo

2015-11-01

The concept of residual, i.e., tidally-averaged, flows through a multiple inlet system is reappraised. The evaluation of the residual through-flow depends on the time interval over which is integrated, in other words, on how one defines the tidal period. It is demonstrated that this definition is ambiguous and that different definitions (based on, e.g., high waters, slack tides, etc.) yield very different results for the residual, also in terms of their long-term statistical properties (median and standard deviation). A basin-wide applicable method of defining the tidal period, in terms of enclosed water volume, is analyzed. We compare the different methods on the basis of high-resolution model results for the Western Dutch Wadden Sea. The multitude of tidal constituents together with wind variability creates broad distributions for the residuals, with standard deviations much larger than the mean or median residual flows.

A new phase modulated binomial-like selective-inversion sequence for solvent signal suppression in NMR.

Science.gov (United States)

Chen, Johnny; Zheng, Gang; Price, William S

2017-02-01

A new 8-pulse Phase Modulated binomial-like selective inversion pulse sequence, dubbed '8PM', was developed by optimizing the nutation and phase angles of the constituent radio-frequency pulses so that the inversion profile resembled a target profile. Suppression profiles were obtained for both the 8PM and W5 based excitation sculpting sequences with equal inter-pulse delays. Significant distortions were observed in both profiles because of the offset effect of the radio frequency pulses. These distortions were successfully reduced by adjusting the inter-pulse delays. With adjusted inter-pulse delays, the 8PM and W5 based excitation sculpting sequences were tested on an aqueous lysozyme solution. The 8 PM based sequence provided higher suppression selectivity than the W5 based sequence. Two-dimensional nuclear Overhauser effect spectroscopy experiments were also performed on the lysozyme sample with 8PM and W5 based water signal suppression. The 8PM based suppression provided a spectrum with significantly increased (~ doubled) cross-peak intensity around the suppressed water resonance compared to the W5 based suppression. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Chlorinated pesticide residues in marine sediments

Digital Repository Service at National Institute of Oceanography (India)

Sarkar, A.; SenGupta, R.

of pesticide in contaminated river water into the Bay of Bengal. Con centration ranges of all these pesticide residues detected were, aldrine: 0.02-0.53, gamma BHC: 0.01-0.21, dieldrine: 0.05-0.51, and total DDT: 0.02-0.78, all in mu g g sup(-1) (wet wt)....

Salt-assisted and salt-suppressed sol-gel transitions of methylcellulose in water.

Science.gov (United States)

Xu, Y; Wang, C; Tam, K C; Li, L

2004-02-03

The effects of various salts on the sol-gel transition of aqueous methylcellulose (MC) solutions have been studied systematically by means of a micro differential scanning calorimeter. It was found that the heating process was endothermic while the cooling process was exothermic for both MC solutions with and without salts. The addition of salts did not change the patterns of gelation and degelation of MC. However, the salts could shift the sol-gel transition and the gel-sol transition to lower or higher temperatures from a pure MC solution, depending on the salt type. These opposite effects were termed the salt-assisted and salt-suppressed sol-gel transitions. Either the salt-assisted transition or the salt-suppressed sol-gel transition was a function of salt concentration. In addition, each salt was found to have its own concentration limit for producing a stable aqueous solution of MC at a given concentration of MC, which was related to the anionic charge density of the salt. Cations were proved to have weaker effects than anions. The "salt-out strength", defined as the salt effect per mole of anion, was obtained for each anion studied. The thermodynamic mechanisms involved in the salt-assisted and salt-suppressed sol-gel transitions are discussed.

Fat suppression applied to MR imaging of the pathologic orbit

International Nuclear Information System (INIS)

Simon, J.H.; Kido, D.K.; Ekholm, S.E.; Totterman, S.; Szumowski, J.; Manzione, J.V. Jr.; Joy, S.E.

1987-01-01

Previous MR studies of the normal orbit have shown that fat suppression sequences applied at the proper T1-T2 weighting will decrease artifacts from chemical shift, and can be used to enhance contrast in selected anatomic regions. The purpose of this study was to evaluate the clinical application of fat suppression to studies of the pathologic orbit. The studies included conventional imaging sequences and comparative fat suppression sequences through a range of T1-T2 weighting (repetition time [TR] 400 msec, echo time [TE]20 msec, to TR 2,000 msec, TE 90 msec), using the chopper fat suppression technique developed by J. Szumowski and D. Plewes, which requires no postprocessing and no increased scan time to achieve relatively linear fat suppression. Fat suppression was advantageous in determining tumor margins (extension through sclera); increasing diagnostic specificity (fat vs. water content); detailing anatomic relationships along bony margins (particularly in the orbital apex); and for demonstrating true thickness of optic nerve separate from adjacent cerebrospinal fluid and fibrous sheath. Disadvantages included susceptibility to motion artifact and a perception of lower quality due to lower overall orbital signal

Melting of Uranium Metal Powders with Residual Salts

International Nuclear Information System (INIS)

Jin-Mok Hur; Dae-Seung Kang; Chung-Seok Seo

2007-01-01

The Advanced Spent Fuel Conditioning Process (ACP) of the Korea Atomic Energy Research Institute focuses on the conditioning of Pressurized Water Reactor spent oxide nuclear fuel. After the oxide reduction step of the ACP, the resultant metal powders containing ∼ 30 wt% residual LiCl-Li 2 O should be melted for a consolidation of the fine metal powders. In this study, we investigated the melting behaviors of uranium metal powders considering the effects of a LiCl-Li 2 O residual salt. (authors)

Pesticide residue profile and nutrient characteristics of the Densu River Basin in Ghana

International Nuclear Information System (INIS)

Fianko, J.R.

2010-01-01

The Densu River Basin is one of the largest agricultural areas in Ghana. About 80% of people living in this area rely on agricultural activities for subsistence. The practice of using pesticides such as organochlorines, organophosphates, carbamates, pyrethroids and several others in agriculture and public health programs have raised concerns about potentially adverse effects on human health and the environment. Assessment of human health implications of non-point sources within a river basin include pesticide residues analysis of water, sediment and fish and monitoring of physico-chemical parameters in waters that serve as source of drinking water for the entire community within the basin. In this study, a field survey was conducted to assess farmers' knowledge of safe handling and use of pesticides. Nutrient chemistry and surface water characteristics of the Densu River and its tributaries, type and levels of pesticide residues and their trends in water, sediment and fish in the basin were also evaluated. The study also assessed the health risk associated with pesticide contamination of fish from the Basin as well as the relationship between land use and groundwater contamination. Generally surface and ground water bodies in the Densu River basin were found to be polluted with respect to nutrients and pesticides. Waters from the basin were found to be fresh, slightly acidic, and weakly mineralized with low chemical constituents. Nitrate (NO 3- N) levels in surface water ranged between 0.12 - 31.07 mgL -1 while ammonia was between 0.01 - 2.10 mgL -1 and that of phosphate was 0.012 - 2.45 mgL -1 . Pesticide residues and metabolites detected in water, sediment and fish samples from the Densu River Basin were organochlorines. In an average 96% of fish samples, 13.69% of sediment and 3.30% of water samples, at least one pesticide residue was detected per sample. Of the numerous pesticides evaluated, γ -HCH, DDT, aldrin, dieldrin, DDE, endosulfan sulphate, �

Pesticide management and their residues in sediments and surface and drinking water in the Mekong Delta, Vietnam.

Science.gov (United States)

Toan, Pham Van; Sebesvari, Zita; Bläsing, Melanie; Rosendahl, Ingrid; Renaud, Fabrice G

2013-05-01

Public concern in Vietnam is increasing with respect to pesticide pollution of the environment and of drinking water resources. While established monitoring programs in the Mekong Delta (MD) focus on the analysis of organochlorines and some organophosphates, the environmental concentrations of more recently used pesticides such as carbamates, pyrethroides, and triazoles are not monitored. In the present study, household level pesticide use and management was therefore surveyed and combined with a one year environmental monitoring program of thirteen relevant pesticides (buprofezin, butachlor, cypermethrin, α-endosulfan, β-endosulfan, endosulfan-sulfate, fenobucarb, fipronil, isoprothiolane, pretilachlor, profenofos, propanil, and propiconazole) in surface water, soil, and sediment samples. The surveys showed that household level pesticide management remains suboptimal in the Mekong Delta. As a consequence, a wide range of pesticide residues were present in water, soil, and sediments throughout the monitoring period. Maximum concentrations recorded were up to 11.24 μg l(-1) in water for isoprothiolane and up to 521 μg kg(-1) dm in sediment for buprofezin. Annual average concentrations ranged up to 3.34 μg l(-1) in water and up to 135 μg kg(-1) dm in sediment, both for isoprothiolane. Occurrence of pesticides in the environment throughout the year and co-occurrence of several pesticides in the samples indicate a considerable chronic exposure of biota and humans to pesticides. This has a high relevance in the delta as water for drinking is often extracted from canals and rivers by rural households (GSO, 2005, and own surveys). The treatment used by the households for preparing surface water prior to consumption (flocculation followed by boiling) is insufficient for the removal of the studied pesticides and boiling can actually increase the concentration of non-volatile pollutants. Copyright © 2012 Elsevier B.V. All rights reserved.

33 CFR 149.416 - What are the requirements for a dry chemical fire suppression system?

Science.gov (United States)

2010-07-01

... the requirements for a dry chemical fire suppression system? Each natural gas deepwater port must be... dry chemical fire suppression system? 149.416 Section 149.416 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: DESIGN, CONSTRUCTION...

Fat suppression techniques for obtaining high resolution dynamic contrast enhanced bilateral breast MR images at 7 tesla

DEFF Research Database (Denmark)

van der Velden, Tijl A; Schmitz, Alexander M Th; Gilhuijs, Kenneth G A

2016-01-01

contained 3D T1-weighted gradient echo images obtained with both WSE fat suppression, multi echo Dixon fat suppression, and without fat suppression. Images were acquired at a (0.8mm)(3) or (0.7mm)(3) isotropic resolution with equal field of view and optimized such to obtain a maximal SNR. Image quality...... was scored qualitatively on overall image quality, sharpness of anatomical details, presence of artefacts, inhomogeneous fat suppression and the presence of water-fat shift. A quantitative scoring was obtained from the signal to noise ratio and contrast to noise ratio. RESULTS: WSE scored significantly...... better in terms of overall image quality and the absence of artefacts. No significant difference in contrast to noise ratio was found between the two fat suppression methods. CONCLUSION: When maximizing temporal and spatial resolution of high resolution DCE MRI of the breast, water selective excitation...

Lysine as helix C-capping residue in a synthetic peptide.

Science.gov (United States)

Esposito, G; Dhanapal, B; Dumy, P; Varma, V; Mutter, M; Bodenhausen, G

1997-01-01

The structure of the synthetic peptide CH3CO(Leu-Ser-Leu-Leu-Leu-Ser-Leu)3Lys-NH2 in trifluoroethanol/water 60/40 (volume ratio) was characterized by two-dimensional nmr spectroscopy. The peptide, closely related to the amphiphilic helix models designed by W. F. De-Grado and co-workers to mimic protein ion channels [(1988) Science, Vol. 240, p. 1177-1181], folds into a regular helix spanning residues 1-20. Evidence for a helix C-terminal capping conformation, involving the terminal lysine residue, was observed from Overhauser effects and checked for consistency by restrained molecular dynamics simulations. The side-chain amino group of Lys22 forms a hydrogen bond with the carbonyl of Leu18, and the distorted helical geometry of the terminal dipeptide allows the inclusion of a water bridge between the backbone NH of the Lys22 residue and the carbonyls of Leu19 and Ser20.

Role of symmetry-breaking induced by Er × B shear flows on developing residual stresses and intrinsic rotation in the TEXTOR tokamak

International Nuclear Information System (INIS)

Xu, Y.; Shesterikov, I.; Berte, M.; Dumortier, P.; Van Schoor, M.; Vergote, M.; Hidalgo, C.; Krämer-Flecken, A.; Koslowski, R.

2013-01-01

Direct measurements of residual stress (force) have been executed at the edge of the TEXTOR tokamak using multitip Langmuir and Mach probes, together with counter-current NBI torque to balance the existing toroidal rotation. Substantial residual stress and force have been observed at the plasma boundary, confirming the existence of a finite residual stress as possible mechanisms to drive the intrinsic toroidal rotation. In low-density discharges, the residual stress displays a quasi-linear dependence on the local pressure gradient, consistent with theoretical predictions. At high-density shots the residual stress and torque are strongly suppressed. The results show close correlation between the residual stress and the E r × B flow shear rate, suggesting a minimum threshold of the E × B flow shear required for the k ∥ symmetry breaking. These findings provide the first experimental evidence of the role of E r × B sheared flows in the development of residual stresses and intrinsic rotation. (letter)

Dissipation and Residue Level of Thifluzamide in Rice Field Ecosystem

Directory of Open Access Journals (Sweden)

Weitao Chen

2015-01-01

Full Text Available An efficient modified QuEChERS method combined with high performance liquid chromatography-tandem mass spectrometry detection (HPLC-MS/MS was established and evaluated for the residue analysis of thifluzamide in rice grain, husk, straw, seedling, paddy water, and soil. Thifluzamide residues were extracted with acetonitrile, cleaned up with primary secondary amine (PSA, and then determined by HPLC-MS/MS. The fortified recoveries were 76%–106% with RSDs of 3%–13%. The results of the supervised field trials at two experiment sites showed that thifluzamide dissipated rapidly in paddy fields, and the half-lives in paddy water, soil, and rice seedling were 0.3–0.6 d, 1.8–3.6 d, and 4.3–13.9 d, respectively. At harvest time, when the preharvest interval (PHI was set as 21 d, the final residues of thifluzamide in rice grains were below the maximum residue limit (MRL of 0.5 mg/kg set by Japan, whereas the final residues in rice husk and straw were still high (the highest value reached 1.36 mg/kg in rice husk and 0.83 mg/kg in rice straw. The results indicated that the highest residue in rice grain was 0.23 mg/kg when PHI was 21 d, and only 6.9–11.0% of acute risk quotient of thifluzamide was occupied by the dietary daily intake in Chinese population consuming rice.

Leaching Behavior of Circulating Fluidised Bed MSWI Air Pollution Control Residue in Washing Process

Directory of Open Access Journals (Sweden)

Zhiliang Chen

2016-09-01

Full Text Available In this study, air pollution control (APC residue is conducted with water washing process to reduce its chloride content. A novel electrical conductivily (EC measurement method is proposed to monitor the dynamic change of chloride concentrations in leachate as well as the chloride content of the residue. The method equally applies to various washing processes with different washing time, liquid/solid ratio and washing frequency. The results show that washing effectively extracts chloride salts from APC residues, including those from circulating fluidized bed (CFB municipal solid waste incineration (MSWI. The most appropriate liquid/solid ratio and washing time in the first washing are found to be around 4 L water per kg of APC residue and 30 min, respectively, and washing twice is required to obtain maximum dissolution. The pH value is the major controlling factor of the heavy metals speciation in leachate, while chloride concentration also affects the speciation of Cd. Water washing causes no perceptible transfer of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs from the APC residue to leachate. The chloride concentration is strongly related with electrical conductivity (EC, as well as with the concentrations of calcium, sodium and potassium of washing water. Their regression analyses specify that soluble chloride salts and EC could act as an indirect indicator to monitor the change of chloride concentration and remaining chloride content, thus, contributing to the selection of the optimal washing conditions.

Bioaccumulation and distribution of organochlorine residues across ...

African Journals Online (AJOL)

Eighteen organochlorine pesticide (OCP) residues were measured in the water, sediment, plankton, benthic invertebrates and fish in various sections of the Lagos Lagoon in 2014 to investigate their bioaccumulation and distribution in the food web. The analysis was done using gas chromatography with an electron capture ...

Dim light adaptation attenuates acute melatonin suppression in humans.

Science.gov (United States)

Jasser, Samar A; Hanifin, John P; Rollag, Mark D; Brainard, George C

2006-10-01

Abstract Studies in rodents with retinal degeneration indicated that neither the rod nor the cone photoreceptors obligatorily participate in circadian responses to light, including melatonin suppression and photoperiodic response. Yet there is a residual phase-shifting response in melanopsin knockout mice, which suggests an alternate or redundant means for light input to the SCN of the hypothalamus. The findings of Aggelopoulos and Meissl suggest a complex, dynamic interrelationship between the classic visual photoreceptors and SCN cell sensitivity to light stimuli, relative to various adaptive lighting conditions. These studies raised the possibility that the phototransductive physiology of the retinohypothalamic tract in humans might be modulated by the visual rod and cone photoreceptors. The aim of the following two-part study was to test the hypothesis that dim light adaptation will dampen the subsequent suppression of melatonin by monochromatic light in healthy human subjects. Each experiment included 5 female and 3 male human subjects between the ages of 18 and 30 years, with normal color vision. Dim white light and darkness adaptation exposures occurred between midnight and 0200 h, and a full-field 460-nm light exposure subsequently occurred between 0200 and 0330-h for each adaptation condition, at 2 different intensities. Plasma samples were drawn following the 2-h adaptation, as well as after the 460-nm monochromatic light exposure, and melatonin was measured by radioimmunoassay. Comparison of melatonin suppression responses to monochromatic light in both studies revealed a loss of significant suppression after dim white light adaptation compared with dark adaptation (p light exposure, varying with the conditions of light adaptation prior to exposure.

The suppression of dissolution for alloy 690 in high temperature and high pressure water with chromium ion implantation

International Nuclear Information System (INIS)

Shibata, Toshio; Fujimoto, Shinji; Ohtani, Saburou; Watanabe, Masanori; Hirao, Kyozo; Okumoto, Masaru; Shibaike, Hiroyuki.

1994-01-01

As the material of heat exchanger tubes for PWRs, the nickel alloys such as alloy 690 and alloy 600 have been used, but 58 Ni and 60 Co contained as an impurity elute in primary cooling water, and are radioactivated, in this way, they become the cause of radiation exposure. By increasing chromium concentration, the corrosion resistance of nickel alloys is improved, and for modern heat exchangers, the alloy 690, of which the chromium content is increased up to 30%, has been adopted, and excellent results have been obtained. In this research, aiming at the further reduction of radiation exposure, by increasing the chromium concentration in surface layer using ion implantation technology, the change of the corrosion behavior of alloy 690 in high temperature, high pressure water was investigated. The chemical composition of the alloy 690 used, and the making of plate specimens are shown. The polarization behavior of alloy 690 in 0.1 mol/l sulfuric acid deaerated at normal temperature is reported, and the effect of suppressing dissolution was remarkable in the specimens with much implantation. The electrochemical behavior of alloy 690 in simulated cooling water was investigated. Immobile case has high chromium content and is thin. (K.I.)

Biodrying of animal slaughterhouse residues and heat production

Energy Technology Data Exchange (ETDEWEB)

Bernard, Y. [Centre de recherche industrielle, Quebec City, PQ (Canada)

2010-07-01

Animal carcasses from slaughterhouses are usually composted on farms, but the composting process is not optimized and a large volumes of carbonaceous residues are needed. This type of composting takes place over a period of 6 to 9 months in a nonaerated static pile. Quebec's industrial research centre (CRIQ) developed an organic biodrying process (BIOSECO) adapted to large-scale operations in order to optimize the treatment of slaughterhouse residues. Biodrying is a form of composting, in which the thermophilic phase is optimized, making it possible to evaporate large amounts of water. Biodrying is done inside a building and reduces the amount of carbonaceous residues considerably. The process is optimized by the sequence in which the slaughterhouse residues are added, the choice of input and the aeration flow. Slaughterhouse residues can be treated non-stop throughout the entire year. Since the odours are nearly completed limited to the building, the biodrying can be done near the slaughterhouse. A large amount of heat was produced by the process during the pilot project. It was concluded that the BIOSECO biodrying process is suitable for treating slaughterhouse residues in an effective and economic manner, and has the added advantage of producing heat that could be used for various purposes.

Residues of 14C-chlorpyrifos in coconut by radiotracer techniques

International Nuclear Information System (INIS)

Tejada, A.W.; Calumpang, S.M.F.; Magallona, E.D.

1992-01-01

A coconut tree was root-infused with 5 g a.i. chlorpyrifos (Lorsban plus 1.4 uCi of 14 C-chlorpyrifos. Coconut samples both young and mature, were taken 24 h up to 60 days after root infusion. Analysis of the meat and water was done. The maximum uptake of chlorpyrifos equivalents was on the 13th day after root infusion both in mature and young fruit. The residue in water reached the peak on the 20th day after infusion and declined thereafter. A preharvest interval (PHI) of more than 60 days maybe recommended for safe consumption. The usual practice of storing copra in treated warehouses until it is processed into oil was simulated in the laboratory to determine the residues absorbed on the meat. Forty kg of copra with moisture content of 7-12% were stored in an improvised warehouse, i.e. 1 m x 1.5 m x 1 m wooden box, which was treated with 100 ml 1% a.i. Lorsban 50 WP plus 100 uCi 14 C-chlorpyrifos for protection against insects. Analysis showed that 14 C-chlorpyrifos equivalents ranged from 22.6 mg/kg on the 30th day to 8.2 mg/kg on the 90th day with a 63.7% reduction in residues. Bound residues were detected on samples stored for 60-90 days, with levels of 1.0 to 0.2 ug/g 14 C-chlorpyrifos equivalents. This is within the Maximum Residue Limit of 2 mg/kg set by FAO/WHO for chlorpyrifos in most agricultural commodities. Chlorpyrifos residues were also determined at various stages of refining and processing of crude coconut oil. It was subjected to alkali refining, bleaching and finally steaming. The residues were reduced by as much as 32.7%. (author). 18 refs.; 2 figs.; 3 tabs

Hanford tank residual waste - Contaminant source terms and release models

International Nuclear Information System (INIS)

Deutsch, William J.; Cantrell, Kirk J.; Krupka, Kenneth M.; Lindberg, Michael L.; Jeffery Serne, R.

2011-01-01

Highlights: → Residual waste from five Hanford spent fuel process storage tanks was evaluated. → Gibbsite is a common mineral in tanks with high Al concentrations. → Non-crystalline U-Na-C-O-P ± H phases are common in the U-rich residual. → Iron oxides/hydroxides have been identified in all residual waste samples. → Uranium release is highly dependent on waste and leachant compositions. - Abstract: Residual waste is expected to be left in 177 underground storage tanks after closure at the US Department of Energy's Hanford Site in Washington State, USA. In the long term, the residual wastes may represent a potential source of contamination to the subsurface environment. Residual materials that cannot be completely removed during the tank closure process are being studied to identify and characterize the solid phases and estimate the release of contaminants from these solids to water that might enter the closed tanks in the future. As of the end of 2009, residual waste from five tanks has been evaluated. Residual wastes from adjacent tanks C-202 and C-203 have high U concentrations of 24 and 59 wt.%, respectively, while residual wastes from nearby tanks C-103 and C-106 have low U concentrations of 0.4 and 0.03 wt.%, respectively. Aluminum concentrations are high (8.2-29.1 wt.%) in some tanks (C-103, C-106, and S-112) and relatively low ( 2 -saturated solution, or a CaCO 3 -saturated water. Uranium release concentrations are highly dependent on waste and leachant compositions with dissolved U concentrations one or two orders of magnitude higher in the tests with high U residual wastes, and also higher when leached with the CaCO 3 -saturated solution than with the Ca(OH) 2 -saturated solution. Technetium leachability is not as strongly dependent on the concentration of Tc in the waste, and it appears to be slightly more leachable by the Ca(OH) 2 -saturated solution than by the CaCO 3 -saturated solution. In general, Tc is much less leachable (<10 wt.% of the

Quests for justice and mechanisms of suppression in Flint, Michigan

DEFF Research Database (Denmark)

Rutt, Rebecca Leigh; Bluwstein, Jevgeniy

2017-01-01

There is widespread acknowledgment of the crisis nature and injustices around water quality and access in Flint since mid-2014. This crisis led to different forms of grassroots activism demanding political accountability, transparency, and redress. However, residents' experiences and their needs...... and demands in response to the crisis have been largely ignored. This article explores the mechanisms of suppression at work in obscuring these needs and demands. Specifically, it sheds light on the role of the public sector, the media, and the academic institutions in reproducing these mechanisms...... of suppression. The article situates the struggles over political accountability within the neoliberalization of public administration and government through emergency management. Capital accumulation can continue and intensifies, whereas emergency management further contributes to suppressing public dissent...

Vent clearing analysis of a Mark III pressure suppression containment

International Nuclear Information System (INIS)

Quintana, R.

1979-01-01

An analysis of the vent clearing transient in a Mark III pressure suppression containment after a hypothetical LOCA is carried out. A two-dimensional numerical model solving the transient fluid dynamic equations is used. The geometry of the pressure suppression pool is represented and the pressure and velocity fields in the pool are obtained from the moment the LOCA occurs until the first vent in the drywell wall clears. The results are compared to those obtained with the one-diemensional model used for containment design, with special interest on two-dimensional effects. Some conclusions concerning the effect of the water discharged into the suppression pool through the vents on submerged structures are obtained. Future improvements to the model are suggested. (orig.)

A Simple Surface-Enhanced Raman Spectroscopic Method for on-Site Screening of Tetracycline Residue in Whole Milk

Directory of Open Access Journals (Sweden)

Sagar Dhakal

2018-02-01

Full Text Available Therapeutic and subtherapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain tetracycline residue. This study developed a simple surface-enhanced Raman spectroscopic (SERS method for on-site screening of tetracycline residue in milk and water. Six batches of silver colloid nanoparticles were prepared for surface enhancement measurement. Milk-tetracycline and water-tetracycline solutions were prepared at seven concentration levels (1000, 500, 100, 10, 1, 0.1, and 0.01 ppm and spiked with silver colloid nanoparticles. A 785 nm Raman spectroscopic system was used for spectral measurement. Tetracycline vibrational modes were observed at 1285, 1317 and 1632 cm−1 in water-tetracycline solutions and 1322 and 1621 cm−1 (shifted from 1317 and 1632 cm−1, respectively in milk-tetracycline solutions. Tetracycline residue concentration as low as 0.01 ppm was detected in both the solutions. The peak intensities at 1285 and 1322 cm−1 were used to estimate the tetracycline concentrations in water and milk with correlation coefficients of 0.92 for water and 0.88 for milk. Results indicate that this SERS method is a potential tool that can be used on-site at field production for qualitative and quantitative detection of tetracycline residues.

A Simple Surface-Enhanced Raman Spectroscopic Method for on-Site Screening of Tetracycline Residue in Whole Milk.

Science.gov (United States)

Dhakal, Sagar; Chao, Kuanglin; Huang, Qing; Kim, Moon; Schmidt, Walter; Qin, Jianwei; Broadhurst, C Leigh

2018-02-01

Therapeutic and subtherapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain tetracycline residue. This study developed a simple surface-enhanced Raman spectroscopic (SERS) method for on-site screening of tetracycline residue in milk and water. Six batches of silver colloid nanoparticles were prepared for surface enhancement measurement. Milk-tetracycline and water-tetracycline solutions were prepared at seven concentration levels (1000, 500, 100, 10, 1, 0.1, and 0.01 ppm) and spiked with silver colloid nanoparticles. A 785 nm Raman spectroscopic system was used for spectral measurement. Tetracycline vibrational modes were observed at 1285, 1317 and 1632 cm -1 in water-tetracycline solutions and 1322 and 1621 cm -1 (shifted from 1317 and 1632 cm -1 , respectively) in milk-tetracycline solutions. Tetracycline residue concentration as low as 0.01 ppm was detected in both the solutions. The peak intensities at 1285 and 1322 cm -1 were used to estimate the tetracycline concentrations in water and milk with correlation coefficients of 0.92 for water and 0.88 for milk. Results indicate that this SERS method is a potential tool that can be used on-site at field production for qualitative and quantitative detection of tetracycline residues.

Remediation of deltamethrin contaminated cotton fields: residual and adsorption assessment

Directory of Open Access Journals (Sweden)

Rafique Uzaira

2016-01-01

Full Text Available Pakistan occupies a significant global position in the growing of high quality cotton. The extensive application of pesticides on agricultural products leads to environmental risk due to toxic residues in air, water and soil. This study examined the chemodynamic effect of Deltamethrin on cotton fields. Samples were collected from the cotton fields of D.G. Khan, Pakistan and analyzed for heavy metal speciation patterns. Batch experiments were administered in order to study the adsorption of Deltamethrin in cotton fields. The effect of different factors including pH, adsorbate dose, and adsorbent mass on adsorption were studied. It was observed that in general, adsorption increased with increases in the mass of adsorbate, although the trends were irregular. Residual fractions of deltamethrin in the soil and water of cotton fields were analyzed to assess concentrations of xenobiotics bound to soil particles. Results indicated that such residues are significantly higher in soil samples due to high Koc in comparison to water, indicating the former is an efficient degradation agent. Results from the batch experiment resulted in 95% removal with alkaline pH and an adsorbent-adsorbate ratio of 250:1. These results may be used to environment friendly resource management policies.

Residual-stress distributions near stainless steel butt weldments

International Nuclear Information System (INIS)

Elligson, W.A.; Shack, W.J.

1978-01-01

Concern for the integrity of stainless steel butt-weldments in boiling-water-reactor (BWR) piping systems has stimulated study of the conditions that cause stress corrosion cracking (SCC) in the heat-affected zones (HAZ) of the weldments. It is generally agreed that a high stress exceeding the initial yield strength is one of the essential elements for crack initiation. Since design procedures usually ensure that load stresses are below initial yield, the source of the high stresses necessary to produce SCC is thought to be the residual stresses due to welding. To examine the level of residual stresses in the weldments of interest, bulk residual stresses were measured on 100 mm (4-in.) and 254 mm (10-in.) diameter Schedule 80 piping weldments using strain relief techniques. Both laboratory welded specimens and field welded specimens from reactors in service were studied. Axial bulk residual stress distributions were obtained at 45 0 intervals around the circumference. At each azimuthal position, the residual stresses were measured at seven axial positions: on the weld centerline and 13, 20, and 25 mm on either side of the weld centerline on both the inside and outside surfaces

Characterization of CTX-M enzymes, quinolone resistance determinants, and antimicrobial residues from hospital sewage, wastewater treatment plant, and river water.

Science.gov (United States)

Conte, Danieli; Palmeiro, Jussara Kasuko; da Silva Nogueira, Keite; de Lima, Thiago Marenda Rosa; Cardoso, Marco André; Pontarolo, Roberto; Degaut Pontes, Flávia Lada; Dalla-Costa, Libera Maria

2017-02-01

Multidrug-resistant (MDR) bacteria are widespread in hospitals and have been increasingly isolated from aquatic environments. The aim of the present study was to characterize extended-spectrum β-lactamase (ESBL) and quinolone-resistant Enterobacteriaceae from a hospital effluent, sanitary effluent, inflow sewage, aeration tank, and outflow sewage within a wastewater treatment plant (WWTP), as well as river water upstream and downstream (URW and DRW, respectively), of the point where the WWTP treated effluent was discharged. β-lactamase (bla) genes, plasmid-mediated quinolone resistance (PMQR), and quinolone resistance-determining regions (QRDRs) were assessed by amplification and sequencing in 55 ESBL-positive and/or quinolone-resistant isolates. Ciprofloxacin residue was evaluated by high performance liquid chromatography. ESBL-producing isolates were identified in both raw (n=29) and treated (n=26) water; they included Escherichia coli (32), Klebsiella pneumoniae (22) and Klebsiella oxytoca (1). Resistance to both cephalosporins and quinolone was observed in 34.4% of E. coli and 27.3% of K. pneumoniae. Resistance to carbapenems was found in 5.4% of K. pneumoniae and in K. oxytoca. Results indicate the presence of bla CTX-M (51/55, 92.7%) and bla SHV (8/55, 14.5%) ESBLs, and bla GES (2/55, 3.6%) carbapenemase-encoding resistance determinants. Genes conferring quinolone resistance were detected at all sites, except in the inflow sewage and aeration tanks. Quinolone resistance was primarily attributed to amino acid substitutions in the QRDR of GyrA (47%) or to the presence of PMQR (aac-(6')-Ib-cr, oqxAB, qnrS, and/or qnrB; 52.9%) determinants. Ciprofloxacin residue was absent only from URW. Our results have shown strains carrying ESBL genes, PMQR determinants, and mutations in the gyrA QRDR genes mainly in hospital effluent, URW, and DRW samples. Antimicrobial use, and the inefficient removal of MDR bacteria and antibiotic residue during sewage treatment, may

Crop residue management in arable cropping systems under a temperate climate. Part 2: Soil physical properties and crop production. A review

Directory of Open Access Journals (Sweden)

Hiel, MP.

2016-01-01

Full Text Available Introduction. Residues of previous crops provide a valuable amount of organic matter that can be used either to restore soil fertility or for external use. A better understanding of the impact of crop residue management on the soil-water-plant system is needed in order to manage agricultural land sustainably. This review focuses on soil physical aspects related to crop residue management, and specifically on the link between soil structure and hydraulic properties and its impact on crop production. Literature. Conservation practices, including crop residue retention and non-conventional tillage, can enhance soil health by improving aggregate stability. In this case, water infiltration is facilitated, resulting in an increase in plant water availability. Conservation practices, however, do not systematically lead to higher water availability for the plant. The influence of crop residue management on crop production is still unclear; in some cases, crop production is enhanced by residue retention, but in others crop residues can reduce crop yield. Conclusions. In this review we discuss the diverse and contrasting effects of crop residue management on soil physical properties and crop production under a temperate climate. The review highlights the importance of environmental factors such as soil type and local climatic conditions, highlighting the need to perform field studies on crop residue management and relate them to specific pedo-climatic contexts.

Potable Water Quality Management Guidance Document

Science.gov (United States)

2007-09-01

include GAC, microfiltration , ultrafiltration or nanofiltration. Because consecutive systems are buying and distributing treated water, their options for...booster chlorination and breakpoint chlorination. Booster chlorination restores chlorine residuals in the distribution system and minimizes initial...and sediments from the system; and 3) remove stagnant water. Removing stagnant water enables systems to restore disinfectant residuals to distant

NMR WaterLOGSY Reveals Weak Binding of Bisphenol A with Amyloid Fibers of a Conserved 11 Residue Peptide from Androgen Receptor.

Directory of Open Access Journals (Sweden)

Julia Asencio-Hernández

Full Text Available There is growing evidence that bisphenol A (BPA, a molecule largely released in the environment, has detrimental effects on ecosystems and on human health. It acts as an endocrine disruptor targeting steroid hormone receptors, such as the estrogen receptor (ER, estrogen-related receptor (ERR and androgen receptor (AR. BPA-derived molecules have recently been shown to interact with the AR N-terminal domain (AR-NTD, which is known to be largely intrinsically disordered. This N-terminal domain contains an 11 residue conserved domain that forms amyloid fibers upon oxidative dimerisation through its strictly conserved Cys240 residue. We investigate here the interaction of BPA, and other potential endocrine disruptors, with AR-NTD amyloid fibers using the WaterLOGSY NMR experiment. We observed a selective binding of these compounds to the amyloid fibers formed by the AR-NTD conserved region and glutamine homopolymers. This observation suggests that the high potency of endocrine disruptors may result, in part, from their ability to bind amyloid forms of nuclear receptors in addition to their cognate binding sites. This property may be exploited to design future therapeutic strategies targeting AR related diseases such as the spinal bulbar muscular atrophy or prostate cancer. The ability of NMR WaterLOGSY experiments to detect weak interactions between small ligands and amyloid fibers may prove to be of particular interest for identifying promising hit molecules.

Comparative study of fat-suppression techniques for hip arthroplasty MR imaging

Energy Technology Data Exchange (ETDEWEB)

Moliere, Sebastien [University Hospital of Strasbourg, Imaging Department, Strasbourg (France); Dillenseger, Jean-Philippe; Kremer, Stephane; Bierry, Guillaume [University Hospital of Strasbourg, Imaging Department, Strasbourg (France); ICube UMR 7357, University of Strasbourg, Strasbourg (France); Ehlinger, Matthieu [ICube UMR 7357, University of Strasbourg, Strasbourg (France); University Hospital of Strasbourg, Orthopaedic Department, Strasbourg (France)

2017-09-15

The goal of this study was to evaluate different fat-suppressed fluid-sensitive sequences in association with different metal artifacts reduction techniques (MARS) to determine which combination allows better fat suppression around metallic hip implants. An experimental study using an MRI fat-water phantom quantitatively evaluated contrast shift induced by metallic hip implant for different fat-suppression techniques and MARS. Then a clinical study with patients addressed to MRI unit for painful hip prosthesis compared these techniques in terms of fat suppression quality and diagnosis confidence. Among sequences without MARS, both T2 Dixon and short tau inversion recuperation (STIR) had significantly lower contrast shift (p < 0.05), Dixon offering the best fat suppression. Adding MARS (view-angle tilting or slice-encoding for metal artifact correction (SEMAC)) to STIR gave better results than Dixon alone, and also better than SPAIR and fat saturation with MARS (p < 0.05). There were no statistically significant differences between STIR with view-angle tilting and STIR with SEMAC in terms of fat suppression quality. STIR sequence is the preferred fluid-sensitive MR sequence in patients with metal implant. In combination with MARS (view-angle tilting or SEMAC), STIR appears to be the best option for high-quality fat suppression. (orig.)

Comparative study of fat-suppression techniques for hip arthroplasty MR imaging.

Science.gov (United States)

Molière, Sébastien; Dillenseger, Jean-Philippe; Ehlinger, Matthieu; Kremer, Stéphane; Bierry, Guillaume

2017-09-01

The goal of this study was to evaluate different fat-suppressed fluid-sensitive sequences in association with different metal artifacts reduction techniques (MARS) to determine which combination allows better fat suppression around metallic hip implants. An experimental study using an MRI fat-water phantom quantitatively evaluated contrast shift induced by metallic hip implant for different fat-suppression techniques and MARS. Then a clinical study with patients addressed to MRI unit for painful hip prosthesis compared these techniques in terms of fat suppression quality and diagnosis confidence. Among sequences without MARS, both T2 Dixon and short tau inversion recuperation (STIR) had significantly lower contrast shift (p < 0.05), Dixon offering the best fat suppression. Adding MARS (view-angle tilting or slice-encoding for metal artifact correction (SEMAC)) to STIR gave better results than Dixon alone, and also better than SPAIR and fat saturation with MARS (p < 0.05). There were no statistically significant differences between STIR with view-angle tilting and STIR with SEMAC in terms of fat suppression quality. STIR sequence is the preferred fluid-sensitive MR sequence in patients with metal implant. In combination with MARS (view-angle tilting or SEMAC), STIR appears to be the best option for high-quality fat suppression.

Comparative study of fat-suppression techniques for hip arthroplasty MR imaging

International Nuclear Information System (INIS)

Moliere, Sebastien; Dillenseger, Jean-Philippe; Kremer, Stephane; Bierry, Guillaume; Ehlinger, Matthieu

2017-01-01

The goal of this study was to evaluate different fat-suppressed fluid-sensitive sequences in association with different metal artifacts reduction techniques (MARS) to determine which combination allows better fat suppression around metallic hip implants. An experimental study using an MRI fat-water phantom quantitatively evaluated contrast shift induced by metallic hip implant for different fat-suppression techniques and MARS. Then a clinical study with patients addressed to MRI unit for painful hip prosthesis compared these techniques in terms of fat suppression quality and diagnosis confidence. Among sequences without MARS, both T2 Dixon and short tau inversion recuperation (STIR) had significantly lower contrast shift (p < 0.05), Dixon offering the best fat suppression. Adding MARS (view-angle tilting or slice-encoding for metal artifact correction (SEMAC)) to STIR gave better results than Dixon alone, and also better than SPAIR and fat saturation with MARS (p < 0.05). There were no statistically significant differences between STIR with view-angle tilting and STIR with SEMAC in terms of fat suppression quality. STIR sequence is the preferred fluid-sensitive MR sequence in patients with metal implant. In combination with MARS (view-angle tilting or SEMAC), STIR appears to be the best option for high-quality fat suppression. (orig.)

Differential RF MEMS interwoven capacitor immune to residual stress warping

KAUST Repository

Elshurafa, Amro M.

2012-07-27

A RF MEMS capacitor with an interwoven structure is designed, fabricated in the PolyMUMPS process and tested in an effort to address fabrication challenges usually faced in MEMS processes. The interwoven structure was found to offer several advantages over the typical MEMS parallel-plate design including eliminating the warping caused by residual stress, eliminating the need for etching holes, suppressing stiction, reducing parasitics and providing differential capability. The quality factor of the proposed capacitor was higher than five throughout a 2–10 GHz range and the resonant frequency was in excess of 20 GHz.

Differential RF MEMS interwoven capacitor immune to residual stress warping

KAUST Repository

Elshurafa, Amro M.; Salama, Khaled N.

2012-01-01

A RF MEMS capacitor with an interwoven structure is designed, fabricated in the PolyMUMPS process and tested in an effort to address fabrication challenges usually faced in MEMS processes. The interwoven structure was found to offer several advantages over the typical MEMS parallel-plate design including eliminating the warping caused by residual stress, eliminating the need for etching holes, suppressing stiction, reducing parasitics and providing differential capability. The quality factor of the proposed capacitor was higher than five throughout a 2–10 GHz range and the resonant frequency was in excess of 20 GHz.

The critical main-chain length for helix formation in water: determined in a peptide series with alternating Aib and Ala residues exclusively and detected with ECD spectroscopy.

Science.gov (United States)

Longo, Edoardo; Moretto, Alessandro; Formaggio, Fernando; Toniolo, Claudio

2011-10-01

Critical main-chain length for peptide helix formation in the crystal (solid) state and in organic solvents has been already reported. In this short communication, we describe our results aiming at assessing the aforementioned parameter in water solution. To this goal, we synthesized step-by-step by solution procedures a complete series of N-terminally acetylated, C-terminally methoxylated oligopeptides, characterized only by alternating Aib and Ala residues, from the dimer to the nonamer level. All these compounds were investigated by electronic circular dichroism in the far-UV region in water solution as a function of chemical structure, namely presence/absence of an ester moiety or a negative charge at the C-terminus, and temperature. We find that the critical main-chain lengths for 3(10)- and α-helices, although still formed to a limited extent, in aqueous solution are six and eight residues, respectively. © 2011 Wiley-Liss, Inc.

Preliminary characterization of residual biomass from Hibiscus ...

African Journals Online (AJOL)

Hibiscus sabdariffa calyces are mainly used for different agro-food and beverages applications. The residual biomass generated contains various useful substances that were extracted and characterized. It contained 23% (w/w) soluble pectic material, a food additive, extracted with hot acidified water (80°C, pH = 1.5) and ...

Soluble carbon in oxisol under the effect of organic residue rates

Directory of Open Access Journals (Sweden)

Gabriela Lúcia Pinheiro

2014-06-01

Full Text Available The application of organic residues to the soil can increase soluble organic carbon (SOC and affect the pH and electrolytic conductivity (EC of the soil. However, the magnitude of these changes depends on the type of residue and the applied dose. This study aimed to evaluate the effect of increasing C rates contained in organic residue on the pH, EC, water-extractable total carbon (WETC, water-extractable organic carbon (WEOC, and water-extractable inorganic carbon (WEIC in soil treated with manure (chicken, swine, and quail, sawdust, coffee husk, and sewage sludge. The levels of total C (TC- KH2PO4, organic carbon (OC- KH2PO4, and inorganic C (IC- KH2PO4 extractable by a 0.1 mol L-1 KH2PO4 solution were also quantified in soil under the effect of increasing rates of chicken and quail manures. The following rates of organic residue C were applied to a dystrophic Red Latosol (Oxisol sample: 0, 2,000, 5,000, 10,000, and 20,000 mg kg-1. The addition of organic residues to the soil increased pH, except in the case of sewage sludge, which acidified the soil. The acidity correction potential of chicken and quail manure was highest, dependent on the manure rate applied; regardless of the dose used, sawdust barely alters the soil pH. At all tested rates, the EC of the soil treated with swine manure, coffee husk, and sawdust remained below 2.0 dS m-1, which is a critical level for salinity-sensitive crops. However, the application of chicken or quail manure and sewage sludge at certain rates increased the EC to values above this threshold level. Highest levels of WETC, WEOC, and WEIC were obtained when chicken and quail manure and coffee husk were applied to the Oxisol. The quantities of SOC extracted by KH2PO4 were higher than the quantities extracted by water, demonstrating the ability of soil to adsorb C into its colloids.

Tingkat residu pestisida dalam daging kelinci peranakan New Zealand White yang diberi pakan limbah pertanian kubis (Brassica oleracea

Directory of Open Access Journals (Sweden)

S. Sulistyaningsih

2013-12-01

Full Text Available ABSTRACT: The study examines fat and water content, and the level of pesticide residues in rabbit’s meat which were fed cabbage leaves waste. The materials used in the study were 12 New Zealand White rabbits raised from 1.5 to 3 months of age. Those rabbits were divided into 3 different groups (large, medium and small based on their initial body weight. The laboratory test shows there were several types of pesticide residues in the cabbage leaves and rabbit’s meat namely endosulfan, profenofos and chlorpyrifos. The lowest pesticide residues were found at small rabbit’s meat groups. In contrast, the fat content as well as the water content was found high at large rabbit’s meat groups. Keywords: rabbits, cabbage, residues, fat content and water content

Auto-acetylation on K289 is not essential for HopZ1a-mediated plant defense suppression

Directory of Open Access Journals (Sweden)

Jose Sebastian Rufian

2015-07-01

Full Text Available The Pseudomonas syringae type III-secreted effector HopZ1a is a member of the HopZ / YopJ superfamily of effectors that triggers immunity in Arabidopsis. We have previously shown that HopZ1a suppresses both local (effector-triggered immunity, ETI and systemic immunity (systemic acquired resistance, SAR triggered by the heterologous effector AvrRpt2. HopZ1a has been shown to possess acetyltransferase activity, and this activity is essential to trigger immunity in Arabidopsis. HopZ1a acetyltransferase activity has been reported to require the auto-acetylation of the effector on a specific lysine (K289 residue. In this paper we analyze the relevance of autoacetylation of lysine residue 289 in HopZ1a ability to suppress plant defenses, and on the light of the results obtained, we also revise its relevance for HopZ1a avirulence activity. Our results indicate that, while the HopZ1aK289R mutant is impaired to some degree in its virulence and avirulence activities, is by no means phenotypically equivalent to the catalytically inactive HopZ1aC216A, since it is still able to trigger a defense response that induces detectable macroscopic HR and effectively protects Arabidopsis from infection, reducing growth of P. syringae within the plant. We also present evidence that the HopZ1aK289R mutant still displays virulence activities, partially suppressing both ETI and SAR.

Application of acetone acetals as water scavengers and derivatization agents prior to the gas chromatographic analysis of polar residual solvents in aqueous samples.

Science.gov (United States)

van Boxtel, Niels; Wolfs, Kris; Van Schepdael, Ann; Adams, Erwin

2015-12-18

The sensitivity of gas chromatography (GC) combined with the full evaporation technique (FET) for the analysis of aqueous samples is limited due to the maximum tolerable sample volume in a headspace vial. Using an acetone acetal as water scavenger prior to FET-GC analysis proved to be a useful and versatile tool for the analysis of high boiling analytes in aqueous samples. 2,2-Dimethoxypropane (DMP) was used in this case resulting in methanol and acetone as reaction products with water. These solvents are relatively volatile and were easily removed by evaporation enabling sample enrichment leading to 10-fold improvement in sensitivity compared to the standard 10μL FET sample volumes for a selection of typical high boiling polar residual solvents in water. This could be improved even further if more sample is used. The method was applied for the determination of residual NMP in an aqueous solution of a cefotaxime analogue and proved to be considerably better than conventional static headspace (sHS) and the standard FET approach. The methodology was also applied to determine trace amounts of ethylene glycol (EG) in aqueous samples like contact lens fluids, where scavenging of the water would avoid laborious extraction prior to derivatization. During this experiment it was revealed that DMP reacts quantitatively with EG to form 2,2-dimethyl-1,3-dioxolane (2,2-DD) under the proposed reaction conditions. The relatively high volatility (bp 93°C) of 2,2-DD makes it possible to perform analysis of EG using the sHS methodology making additional derivatization reactions superfluous. Copyright © 2015 Elsevier B.V. All rights reserved.

Endosulfan residues in fish from the MUDA rice agroecosystem

International Nuclear Information System (INIS)

Nashriyah Mat; Sabri Junoh; Nuriati Nurdin

2002-01-01

A study was carried out in the recycled and the non-recycled areas of the Muda rice agroecosystem to determine the residue level of endosulfan in rice field fish. Snakehead or haruan (Channa striata), climbing perch or puyu (Anabas testudineus), walking catfish or keli (Clariasspp.) and snakeskin gouramy or sepat siam (Trichogasterpectoralis) were sampled and the tissues analysed using Gas Liquid Chromatography. Endosulfan sulphate metabolite was a ubiquitous residue in all fish at levels ranging from 0.0065 μg/g to 0.9837 μg/g of tissue wet weight whilst α-isomer was detected at a much lower concentration followed by β-isomer. In Channa striata, endosulfan total residue (α+β+sulphate) was accumulated in fish tissues sampled at ACRBD4 (non-recycled) site followed by Blok 14 (recycled) site. Endosulfan residue concentration did not coincide with water recycling practice nor changes in EROD enzyme activity. (Author)

Factors Affecting Transfer of Pyrethroid Residues from Herbal Teas to Infusion and Influence of Physicochemical Properties of Pesticides

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Jin-Jing Xiao

2017-09-01

Full Text Available The transfer of pesticide residues from herbal teas to their infusion is a subject of particular interest. In this study, a multi-residue analytical method for the determination of pyrethroids (fenpropathrin, beta-cypermethrin, lambda-cyhalothrin, and fenvalerate in honeysuckle, chrysanthemum, wolfberry, and licorice and their infusion samples was validated. The transfer of pyrethroid residues from tea to infusion was investigated at different water temperatures, tea/water ratios, and infusion intervals/times. The results show that low amounts (0–6.70% of pyrethroids were transferred under the different tea brewing conditions examined, indicating that the infusion process reduced the pyrethroid content in the extracted liquid by over 90%. Similar results were obtained for the different tea varieties, and pesticides with high water solubility and low octanol–water partition coefficients (log Kow exhibited high transfer rates. Moreover, the estimated values of the exposure risk to the pyrethroids were in the range of 0.0022–0.33, indicating that the daily intake of the four pyrethroid residues from herbal tea can be regarded as safe. The present results can support the identification of suitable tea brewing conditions for significantly reducing the pesticide residue levels in the infusion.

[Interlaboratory Study on Evaporation Residue Test for Food Contact Products (Report 1)].

Science.gov (United States)

Ohno, Hiroyuki; Mutsuga, Motoh; Abe, Tomoyuki; Abe, Yutaka; Amano, Homare; Ishihara, Kinuyo; Ohsaka, Ikue; Ohno, Haruka; Ohno, Yuichiro; Ozaki, Asako; Kakihara, Yoshiteru; Kobayashi, Hisashi; Sakuragi, Hiroshi; Shibata, Hiroshi; Shirono, Katsuhiro; Sekido, Haruko; Takasaka, Noriko; Takenaka, Yu; Tajima, Yoshiyasu; Tanaka, Aoi; Tanaka, Hideyuki; Tonooka, Hiroyuki; Nakanishi, Toru; Nomura, Chie; Haneishi, Nahoko; Hayakawa, Masato; Miura, Toshihiko; Yamaguchi, Miku; Watanabe, Kazunari; Sato, Kyoko

2018-01-01

An interlaboratory study was performed to evaluate the equivalence between an official method and a modified method of evaporation residue test using three food-simulating solvents (water, 4% acetic acid and 20% ethanol), based on the Japanese Food Sanitation Law for food contact products. Twenty-three laboratories participated, and tested the evaporation residues of nine test solutions as blind duplicates. For evaporation, a water bath was used in the official method, and a hot plate in the modified method. In most laboratories, the test solutions were heated until just prior to evaporation to dryness, and then allowed to dry under residual heat. Statistical analysis revealed that there was no significant difference between the two methods, regardless of the heating equipment used. Accordingly, the modified method provides performance equal to the official method, and is available as an alternative method.

Reduction of residual stresses in internal skin of transient zones of PWR steam generator expanded tubes: tests with a ''rotating brush''

International Nuclear Information System (INIS)

Vidal, P.

1984-04-01

A process aiming at preventing or suppressing cracks under stress corrosion on the primary side in the expanded zones of PWR steam generator tubes has been studied; it consists in hammering the internal skin of tubes in these zones what reduces the level of residual expanding stresses to lower values around 100-150 MPa without modifying the stress level in external skin. Tests in magnesium chloride to estimate the residual stresses of tubes in low carbon stainless austenitic steel 18% Cr-12% Ni with molybdene [fr

Advanced new technologies for residue upgrading

International Nuclear Information System (INIS)

Gillis, D.

1997-01-01

Viewgraphs summarizing UOP technologies for residue are provided. The upgrading technologies include: (1) Aquaconversion, (2) the Discriminatory Destructive Distillation process (3D), and (3) the RCD uniflex process. The Aquaconversion process is based on catalytic hydrovisbreaking. It makes use of a homogeneous (liquid phase) catalyst. The hydrogen is derived from water. The advantages of this process are improved residue stability and quality at higher conversion levels, high synthetic crude yields, low operational complexity, reduced transportation costs. The 3D process is a unique carbon rejection contaminant removal process which can process whole crudes through viscous residues. FCC type equipment is used. Performance characteristics and advantages of the process were highlighted. The RCD uniflex process makes use of proven fixed bed and ebullated bed technologies in a new process configuration in which the fixed bed system is located upstream of the ebullated bed system. In this process, the catalyst volume increases exponentially with increasing processing severity. Performance characteristics, design features, benefits and development progress to date are described. 1 tab., 21 figs

Development of a suppression method for deposition of radioactive cobalt after chemical decontamination: Confirmation of the Suppression Mechanism with Preoxidized Ferrite Film for Deposition of Radioactive Cobalt

International Nuclear Information System (INIS)

Ito, Tsuyoshi; Hosokawa, Hideyuki; Nagase, Makoto; Aizawa, Motohiro; Fuse, Motomasa

2012-09-01

Recently, chemical decontamination at the beginning of a periodical inspection is applied to many Japanese boiling water reactor (BWR) plants in order to reduce radiation exposure. In the chemical decontamination, the oxides that have incorporated 60 Co are dissolved using reductive and oxidative chemical reagents. Some of the piping stainless steel (SS) base metal is exposed to the reactor water after this decontamination. The oxide film growth rate of the piping during plant operation just after the decontamination is higher than that just before it. Therefore, there is a possibility that the deposition amount of 60 Co on the piping just after decontamination is higher than that just before the chemical decontamination. The Hi-F Coat (Hitachi ferrite coating) process has been developed to lower recontamination after the chemical decontamination. In this process, a fine Fe 3 O 4 coating film is formed on the piping SS base metal in aqueous solution at 363 K using three chemical reagents: ferrous ion, oxidant, and pH adjuster. The growth rate of the corrosion oxide film that incorporated 60 Co on the piping during plant operation is suppressed by the fine ferrite film that blocks both diffusion of oxidant in the reactor water to the SS base metal and metal ions in the oxide film to the reactor water. As a result, the amount of 60 Co deposition is suppressed by the Hi-F coating film. In a previous report, we found that the Hi-F Coat process lowered the amount of 60 Co to 1/3 that for non-coated specimens. To improve the suppression of 60 Co deposition further, we combined the Hi-F Coat process with a pre-oxidation step which we named the pre-oxidized Hi-F Coat process. In laboratory experiments, using the pre-oxidized Hi-F Coat process we found the deposited amount of 60 Co was 1/10 that for non-coated specimens. By combining the Hi-F Coat process with the pre-oxidation step, the suppression effect of 60 Co deposition was three times higher than that of the Hi

Formulation of morning product using food residues

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Maria do Rosário de Fátima Padilha

2017-09-01

Full Text Available In Brazil, there is resistance of the population to the use of stalks, leaves, peels and seeds of vegetables and fruits, leading to trash important parts of the food in good physiological conditions and with the presence of potential nutrients. In this research, a morning product was elaborated using green and dry coconut residue, jerimum and melon seed, crystallized sicilian lemon peel, cashew nut, common rapadura sweet and ginger. The bacteriological tests proved the hygienic-sanitary quality of the product, therefore suitable for consumption, that is, according to RDC 12/2001. It was also observed that the dehydration of all the residues reached the legal levels and accepted by ANVISA that limits in 25% the water content in the dehydrated foods. As for the centesimal composition, it was observed that the elaborated product with residues and other ingredients had a good content of macro nutrients. A use of the type of waste as a new food proposal constitutes an alternative to avoid and reduce: the serious environmental problem caused by the large residual volume generated, and the inadequate places in which they are stored or deposited, aggravating the scenario of food-borne pollutants.

Volumetric fat-water separated T2-weighted MRI

International Nuclear Information System (INIS)

Vasanawala, Shreyas S.; Sonik, Arvind; Madhuranthakam, Ananth J.; Venkatesan, Ramesh; Lai, Peng; Brau, Anja C.S.

2011-01-01

Pediatric body MRI exams often cover multiple body parts, making the development of broadly applicable protocols and obtaining uniform fat suppression a challenge. Volumetric T2 imaging with Dixon-type fat-water separation might address this challenge, but it is a lengthy process. We develop and evaluate a faster two-echo approach to volumetric T2 imaging with fat-water separation. A volumetric spin-echo sequence was modified to include a second shifted echo so two image sets are acquired. A region-growing reconstruction approach was developed to decompose separate water and fat images. Twenty-six children were recruited with IRB approval and informed consent. Fat-suppression quality was graded by two pediatric radiologists and compared against conventional fat-suppressed fast spin-echo T2-W images. Additionally, the value of in- and opposed-phase images was evaluated. Fat suppression on volumetric images had high quality in 96% of cases (95% confidence interval of 80-100%) and were preferred over or considered equivalent to conventional two-dimensional fat-suppressed FSE T2 imaging in 96% of cases (95% confidence interval of 78-100%). In- and opposed-phase images had definite value in 12% of cases. Volumetric fat-water separated T2-weighted MRI is feasible and is likely to yield improved fat suppression over conventional fat-suppressed T2-weighted imaging. (orig.)

Recycling of air pollution control residues from municipal solid waste incineration into lightweight aggregates.

Science.gov (United States)

Quina, Margarida J; Bordado, João M; Quinta-Ferreira, Rosa M

2014-02-01