Science.gov

Sample records for water absorption capacity

  1. Determination of water absorption and water holding capacities of different soil mixtures with MINIDRAIN system to enhance the plant growth

    NASA Astrophysics Data System (ADS)

    Sudan Acharya, Madhu; Rauchecker, Markus; Wu, Wei

    2014-05-01

    Soil water holding capacity is the amount of water that a given soil can hold against the force of gravity. Soil texture and organic matter are the key components that determine soil water holding capacity. Soils with smaller particle sizes, such as silt and clay have larger surface area can hold more water compared to sand which has large particle sizes which results in smaller surface area. A study report showed that 1% increase in soil humus will result in a 4% increase in stored soil water (Morris, 2004) and 1 part humus holds 4 parts of water (Wheeler and Ward, 1998). Therefore, the more humus that can be added to the soil, the greater the water holding capacity of the soil. As the level of organic matter increases in a soil, the water holding capacity also increases due to the affinity of organic matter for water. The water holding capacity of the soil is determined by the amount of water held in the soil sample vs. the dry weight of the sample. MINIDRAIN is a patented system made of geo-fabric (fleece) or combination of geosynthetics and humus. MINIDRAIN and vegetation nets developed by the company ÖKO-TEX (Linz, Austria) will improve the distribution of water and air in the soils, increase the growth of vegetation and reduce the soil erosion. Depending on the physical configuration, there are four different combinations of MINIDRAIN systems developed by ÖKO-TEX. a) Geotextile (fleece) strips of different sizes (e.g. 5x10x250 mm) b) Net formed strips (drainage nets) of different sizes c) Multilayer geotextile mats with humus, seeds or compost of different sizes (e.g. 10x30x200 mm) d) Multilayer geotextile net formed mats with humus, seeds or compost This paper describes the experimental results of the water absorption and water holding capacity of different forms of MINIDRAIN under different soil mixes. In this experiment, potting soil, coarse sand and LECA (Light weight clay aggregates) balls are mixed with different proportion of MINIDRAIN systems and

  2. Influence of particle size on water absorption capacity and mechanical properties of polyethylene-wood flour composites

    NASA Astrophysics Data System (ADS)

    Zykova, A. K.; Pantyukhov, P. V.; Kolesnikova, N. N.; Popov, A. A.; Olkhov, A. A.

    2015-10-01

    Biocomposites based on low density polyethylene (LDPE) and birch wood flour (WF) were investigated. The mechanical properties and water absorption capacity were examined depending on the particle size of a filler in biocomposites. The aim of the paper is the investigation of composite properties depending on the filler particle size. The filler particle sizes were 0-80 µm, 80-140 µm, 140-200 µm, and 0-200 µm. The tensile strength of composite samples varied within the range 5.7-8.2 MPa. Elongation at break of composites varied within the range 5.1-7.5%. Highest mechanical properties were found in composites with the lowest filler fraction. Highest water absorption was observed in composition with a complex fraction of the filler. The influence of the filler particle size on composite properties was shown. It was found that an increase of the filler particle size decreases mechanical parameters and increases water absorption.

  3. Capacity for Absorption of Water-Soluble Secondary Metabolites Greater in Birds than in Rodents

    PubMed Central

    Karasov, William H.; Caviedes-Vidal, Enrique; Bakken, Bradley Hartman; Izhaki, Ido; Samuni-Blank, Michal; Arad, Zeev

    2012-01-01

    Plant secondary metabolites (SMs) are pervasive in animal foods and potentially influence feeding behavior, interspecies interactions, and the distribution and abundance of animals. Some of the major classes of naturally occurring SMs in plants include many water-soluble compounds in the molecular size range that could cross the intestinal epithelium via the paracellular space by diffusion or solvent drag. There are differences among species in paracellular permeability. Using Middle Eastern rodent and avian consumers of fruits containing SMs, we tested the hypothesis that avian species would have significantly higher paracellular permeability than rodent species. Permeability in intact animals was assessed using standard pharmacological methodology to measure absorption of two radiolabeled, inert, neutral water-soluble probes that do not interact with intestinal nutrient transporters, L-arabinose (Mr = 150.1 Da) and lactulose (Mr = 342.3 Da). We also measured absorption of labeled 3-O-methyl-D-glucose (3OMD-glucose; Mr = 194.2 Da), which is a nonmetabolized analogue of D-glucose that is passively absorbed through the paracellular space but also transported across the enterocyte membranes. Most glucose was absorbed by all species, but arabinose fractional absorption (f) was nearly three times higher in birds (1.03±0.17, n = 15 in two species) compared to rodents (0.37±0.06, n = 10 in two species) (P<0.001). Surprisingly, the apparent rates of absorption in birds of arabinose exceeded those of 3OMD-glucose. Our findings are in agreement with previous work showing that the paracellular pathway is more prominent in birds relative to nonflying mammals, and suggests that birds may be challenged by greater absorption of water-soluble, dietary SMs. The increased expression of the paracellular pathway in birds hints at a tradeoff: the free energy birds gain by absorbing water-soluble nutrients passively may be offset by the metabolic demands placed on

  4. Capacity for absorption of water-soluble secondary metabolites greater in birds than in rodents.

    PubMed

    Karasov, William H; Caviedes-Vidal, Enrique; Bakken, Bradley Hartman; Izhaki, Ido; Samuni-Blank, Michal; Arad, Zeev

    2012-01-01

    Plant secondary metabolites (SMs) are pervasive in animal foods and potentially influence feeding behavior, interspecies interactions, and the distribution and abundance of animals. Some of the major classes of naturally occurring SMs in plants include many water-soluble compounds in the molecular size range that could cross the intestinal epithelium via the paracellular space by diffusion or solvent drag. There are differences among species in paracellular permeability. Using Middle Eastern rodent and avian consumers of fruits containing SMs, we tested the hypothesis that avian species would have significantly higher paracellular permeability than rodent species. Permeability in intact animals was assessed using standard pharmacological methodology to measure absorption of two radiolabeled, inert, neutral water-soluble probes that do not interact with intestinal nutrient transporters, L-arabinose (M(r) = 150.1 Da) and lactulose (M(r) = 342.3 Da). We also measured absorption of labeled 3-O-methyl-D-glucose (3OMD-glucose; M(r) = 194.2 Da), which is a nonmetabolized analogue of D-glucose that is passively absorbed through the paracellular space but also transported across the enterocyte membranes. Most glucose was absorbed by all species, but arabinose fractional absorption (f) was nearly three times higher in birds (1.03±0.17, n = 15 in two species) compared to rodents (0.37±0.06, n = 10 in two species) (P<0.001). Surprisingly, the apparent rates of absorption in birds of arabinose exceeded those of 3OMD-glucose. Our findings are in agreement with previous work showing that the paracellular pathway is more prominent in birds relative to nonflying mammals, and suggests that birds may be challenged by greater absorption of water-soluble, dietary SMs. The increased expression of the paracellular pathway in birds hints at a tradeoff: the free energy birds gain by absorbing water-soluble nutrients passively may be offset by the metabolic demands

  5. Meta-Analysis of the Copper, Zinc, and Cadmium Absorption Capacities of Aquatic Plants in Heavy Metal-Polluted Water.

    PubMed

    Li, Jing; Yu, Haixin; Luan, Yaning

    2015-11-26

    The use of aquatic plants for phytoremediation is an important method for restoring polluted ecosystems. We sought to analyze the capacity of different aquatic plant species to absorb heavy metals and to summarize available relevant scientific data on this topic. We present a meta-analysis of Cu, Zn, and Cd absorption capacities of aquatic plants to provide a scientific basis for the selection of aquatic plants suitable for remediation of heavy-metal pollution. Plants from the Gramineae, Pontederiaceae, Ceratophyllaceae, Typhaceae and Haloragaceae showed relatively strong abilities to absorb these metals. The ability of a particular plant species to absorb a given metal was strongly correlated with its ability to absorb the other metals. However, the absorption abilities varied with the plant organ, with the following trend: roots > stems > leaves. The pH of the water and the life habits of aquatic plants (submerged and emerged) also affect the plant's ability to absorb elements. Acidic water aids the uptake of heavy metals by plants. The correlation observed between element concentrations in plants with different aquatic life habits suggested that the enrichment mechanism is related to the surface area of the plant exposed to water. We argue that this meta-analysis would aid the selection of aquatic plants suitable for heavy-metal absorption from polluted waters.

  6. Meta-Analysis of the Copper, Zinc, and Cadmium Absorption Capacities of Aquatic Plants in Heavy Metal-Polluted Water

    PubMed Central

    Li, Jing; Yu, Haixin; Luan, Yaning

    2015-01-01

    The use of aquatic plants for phytoremediation is an important method for restoring polluted ecosystems. We sought to analyze the capacity of different aquatic plant species to absorb heavy metals and to summarize available relevant scientific data on this topic. We present a meta-analysis of Cu, Zn, and Cd absorption capacities of aquatic plants to provide a scientific basis for the selection of aquatic plants suitable for remediation of heavy-metal pollution. Plants from the Gramineae, Pontederiaceae, Ceratophyllaceae, Typhaceae and Haloragaceae showed relatively strong abilities to absorb these metals. The ability of a particular plant species to absorb a given metal was strongly correlated with its ability to absorb the other metals. However, the absorption abilities varied with the plant organ, with the following trend: roots > stems > leaves. The pH of the water and the life habits of aquatic plants (submerged and emerged) also affect the plant’s ability to absorb elements. Acidic water aids the uptake of heavy metals by plants. The correlation observed between element concentrations in plants with different aquatic life habits suggested that the enrichment mechanism is related to the surface area of the plant exposed to water. We argue that this meta-analysis would aid the selection of aquatic plants suitable for heavy-metal absorption from polluted waters. PMID:26703632

  7. Superhydrophobic and superoleophilic polydimethylsiloxane-coated cotton for oil-water separation process: An evidence of the relationship between its loading capacity and oil absorption ability.

    PubMed

    Jin, Yangxin; Jiang, Peng; Ke, Qingping; Cheng, Feihuan; Zhu, Yinshengnan; Zhang, Yixiang

    2015-12-30

    Developing functional porous materials with highly efficient oil-water separation ability are of great importance due to the global scale of severe water pollution arising from oil spillage and chemical leakage. A solution immersion process was used to fabricate polydimethylsiloxane (PDMS)-coated cotton, which exhibited superhydrophobic and superoleophilic properties. The water contact angle of ∼ 157° and mass of ∼ 1.49 g were retained after 1000 compression cycles, indicating that the PDMS was strongly attached to the cotton fibres. The PDMS-coated cotton absorbed various oils and organic solvents with high selectivity, high absorption capacity (up to 7080 wt.%), and good recyclability (exceeding 500 cycles). Notably, the loading capacity of the PDMS-coated cotton against water exhibited a similar trend to its oil absorption capacity. These findings will further the application of superhydrophobic and superoleophilic porous materials in oil/water separation.

  8. Modification of water absorption capacity of a plastic based on bean protein using gamma irradiated starches as additives

    NASA Astrophysics Data System (ADS)

    Köber, E.; Gonzalez, M. E.; Gavioli, N.; Salmoral, E. M.

    2007-01-01

    Some properties of a bean protein-starch plastic were modified by irradiation of the starch. Two kinds of starch from bean and cassava were irradiated with doses until 50 kGy before their inclusion in the composite. Water absorption of the resultant product was reduced by 36% and 60% in materials containing bean and cassava starch, respectively. A large decline in the elongation is observed till 10 kGy in both materials, while tensile strength diminished by 11% in the cassava composite.

  9. Evaluation of an Absorption Heat Pump to Mitigate Plant Capacity Reduction Due to Ambient Temperature Rise for an Air-Cooled Ammonia and Water Cycle: Preprint

    SciTech Connect

    Bharathan, D.; Nix, G.

    2001-08-06

    Air-cooled geothermal plants suffer substantial decreases in generating capacity at increased ambient temperatures. As the ambient temperature rises by 50 F above a design value of 50 F, at low brine-resource temperatures, the decrease in generating capacity can be more than 50%. This decrease is caused primarily by increased condenser pressure. Using mixed-working fluids has recently drawn considerable attention for use in power cycles. Such cycles are more readily amenable to use of absorption ''heat pumps.'' For a system that uses ammonia and water as the mixed-working fluid, this paper evaluates using an absorption heat pump to reduce condenser backpressure. At high ambient temperatures, part of the turbine exhaust vapor is absorbed into a circulating mixed stream in an absorber in series with the main condenser. This steam is pumped up to a higher pressure and heated to strip the excess vapor, which is recondensed using an additional air-cooled condenser. The operating conditions are chosen to reconstitute this condensate back to the same concentration as drawn from the original system. We analyzed two power plants of nominal 1-megawatt capacity. The design resource temperatures were 250 F and 300 F. Ambient temperature was allowed to rise from a design value of 50 F to 100 F. The analyses indicate that using an absorption heat pump is feasible. For the 300 F resource, an increased brine flow of 30% resulted in a net power increase of 21%. For the 250 F resource, the increase was smaller. However, these results are highly plant- and equipment-specific because evaluations must be carried out at off-design conditions for the condenser. Such studies should be carried out for specific power plants that suffer most from increased ambient temperatures.

  10. Analyzing Water's Optical Absorption

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A cooperative agreement between World Precision Instruments (WPI), Inc., and Stennis Space Center has led the UltraPath(TM) device, which provides a more efficient method for analyzing the optical absorption of water samples at sea. UltraPath is a unique, high-performance absorbance spectrophotometer with user-selectable light path lengths. It is an ideal tool for any study requiring precise and highly sensitive spectroscopic determination of analytes, either in the laboratory or the field. As a low-cost, rugged, and portable system capable of high- sensitivity measurements in widely divergent waters, UltraPath will help scientists examine the role that coastal ocean environments play in the global carbon cycle. UltraPath(TM) is a trademark of World Precision Instruments, Inc. LWCC(TM) is a trademark of World Precision Instruments, Inc.

  11. The Zone of Inertia: Absorptive Capacity and Organizational Change

    ERIC Educational Resources Information Center

    Godkin, Lynn

    2010-01-01

    Purpose: The purpose of this paper is to describe how interruptions in organizational learning effect institutional absorptive capacity and contribute to organizational inertia. Design/methodology/approach: An exploratory model is presented as a heuristic to describe how interruptions in organizational learning affect absorptive capacity.…

  12. Intestinal Water Absorption Varies with Expected Dietary Water Load among Bats but Does Not Drive Paracellular Nutrient Absorption.

    PubMed

    Price, Edwin R; Brun, Antonio; Gontero-Fourcade, Manuel; Fernández-Marinone, Guido; Cruz-Neto, Ariovaldo P; Karasov, William H; Caviedes-Vidal, Enrique

    2015-01-01

    Rapid absorption and elimination of dietary water should be particularly important to flying species and were predicted to vary with the water content of the natural diet. Additionally, high water absorption capacity was predicted to be associated with high paracellular nutrient absorption due to solvent drag. We compared the water absorption rates of sanguivorous, nectarivorous, frugivorous, and insectivorous bats in intestinal luminal perfusions. High water absorption rates were associated with high expected dietary water load but were not highly correlated with previously measured rates of (paracellular) arabinose clearance. In conjunction with these tests, we measured water absorption and the paracellular absorption of nutrients in the intestine and stomach of vampire bats using luminal perfusions to test the hypothesis that the unique elongated vampire stomach is a critical site of water absorption. Vampire bats' gastric water absorption was high compared to mice but not compared to their intestines. We therefore conclude that (1) dietary water content has influenced the evolution of intestinal water absorption capacity in bats, (2) solvent drag is not the only driver of paracellular nutrient absorption, and (3) the vampire stomach is a capable but not critical location for water absorption.

  13. Absorption Capacity of Ammonia into Ionic Liquids for Absorption Refrigeration Applications

    NASA Astrophysics Data System (ADS)

    Ariyadi, H. M.; Coronas, A.

    2016-09-01

    In this paper ionic liquids are proposed as a novel absorbent for absorption refrigeration application with ammonia as refrigerant. The main objective of this work is to develop a measurement setup to study the absorption capacity of the ammonia vapour in ionic liquids in a pool type absorber. This investigation is essential in order to identify the most suitable ionic liquid as an absorbent for ammonia refrigerant. The ionic liquids studied in this work are combinations of two different cations ([EtOHmim]+ and [emim]+) and three different anions ([BF4]-, [NTf2]- and [EtSO4]-). The absorption processes are observed within 20 minutes in each experiment at different temperatures and pressures. The detail of the methodology and experimental setup are explained in this paper and measurement results of absorption capacity of ammonia into ionic liquid are discussed. Among all ionic liquids studied in this paper [EtOHmim]+ based ionic liquids shows higher absorption capacity than [emim]+ based ionic liquids, which means that the OH structure in the cation may improve the absorption capacity of ammonia.

  14. Achieving high energy absorption capacity in cellular bulk metallic glasses

    PubMed Central

    Chen, S. H.; Chan, K. C.; Wu, F. F.; Xia, L.

    2015-01-01

    Cellular bulk metallic glasses (BMGs) have exhibited excellent energy-absorption performance by inheriting superior strength from the parent BMGs. However, how to achieve high energy absorption capacity in cellular BMGs is vital but mysterious. In this work, using step-by-step observations of the deformation evolution of a series of cellular BMGs, the underlying mechanisms for the remarkable energy absorption capacity have been investigated by studying two influencing key factors: the peak stress and the decay of the peak stress during the plastic-flow plateau stages. An analytical model of the peak stress has been proposed, and the predicted results agree well with the experimental data. The decay of the peak stress has been attributed to the geometry change of the macroscopic cells, the formation of shear bands in the middle of the struts, and the “work-softening” nature of BMGs. The influencing factors such as the effect of the strut thickness and the number of unit cells have also been investigated and discussed. Strategies for achieving higher energy absorption capacity in cellular BMGs have been proposed. PMID:25973781

  15. The capacity for paracellular absorption in the insectivorous bat Tadarida brasiliensis.

    PubMed

    Fasulo, Verónica; Zhang, ZhiQiang; Chediack, Juan G; Cid, Fabricio D; Karasov, William H; Caviedes-Vidal, Enrique

    2013-02-01

    Water-soluble nutrients are absorbed by the small intestine via transcellular and paracellular processes. The capacity for paracellular absorption seems greater in fliers than in nonfliers, although that conclusion rests mainly on a comparison of flying birds and nonflying mammals because only two frugivorous bat species have been studied. Furthermore, the bats studied so far were relatively large (>85 g, compared with most bat species which are <20 g) and were not insectivores (like about 70 % of bat species). We studied the small (11 g) insectivorous bat Tadarida brasiliensis and tested the prediction that the capacity for paracellular absorption would be as high as in the other bat and avian species studied so far, well above that in terrestrial, nonflying mammals. Using standard pharmacokinetic technique, we measured the extent of absorption (fractional absorption = f) of inert carbohydrate probes: L-arabinose (MM = 150.13) absorbed exclusively by paracellular route and 3OMD-glucose (MM = 194) absorbed both paracellularly and transcellularly. As predicted, the capacity of paracellular absorption in this insectivorous bat was high (L-arabinose f = 1.03 ± 0.14) as in other frugivorous bats and small birds. Absorption of 3OMD-glucose was also complete (f = 1.09 ± 0.17), but >80 % was accounted for by paracellular absorption. We conclude that passive paracellular absorption of molecules of the size of amino acids and glucose is extensive in this bat and, generally in bats, significantly higher than that in nonflying mammals, although the exact extent can be somewhat lower or higher depending on molecule size, polarity and charge.

  16. Enhancing climate Adaptation Capacity for Drinking Water ...

    EPA Pesticide Factsheets

    Journal article This paper considers the adaptation capacity of conventional water treatment systems. A modeling framework is used to illustrate climate adaptation mechanisms that could enable conventional treatment systems to accommodate water quality impairments.

  17. Water-lithium bromide double-effect absorption cooling analysis

    NASA Astrophysics Data System (ADS)

    Vliet, G. C.; Lawson, M. B.; Lithgow, R. A.

    1980-12-01

    A numerical model was developed for the transient simulation of the double-effect, water-lithium bromide absorption cooling machine and was used to determine the effect of the various design and input variables on the absorption unit performance. The performance parameters considered were coefficient of performance and cooling capacity. The variables considered include source hot water, cooling water, and chilled water temperatures; source hot water, cooling water, and chilled water flow rates; solution circulation rate; heat exchanger areas; pressure drop between evaporator and absorber; solution pump characteristics; and refrigerant flow control methods. The performance sensitivity study indicates that the distribution of heat exchanger area among the various (seven) heat exchange components is a very important design consideration. Moreover, it indicated that the method of flow control of the first effect refrigerant vapor through the second effect is a critical design feature when absorption units operate over a significant range of cooling capacity. The model was used to predict the performance of the Trane absorption unit with fairly good accuracy.

  18. Optical absorption coefficients of pure water

    NASA Astrophysics Data System (ADS)

    Lu, Zheng; Zhao, Xianzhen; Fry, Edward S.

    2002-10-01

    The integrating cavity absorption meter(ICAM), which is independent of scattering effect, is used to measure the absolute values of small optical absorption coefficients of liquid. A modified ICAM is being used to measure the absorption of water in the wavelength range 300 to 700 nm. The ultrapure water produced by a two-stages water purification system reaches Type I quality. This is equal to or better than ASTM,CAP and NCCLS water quality standards. To avoid the fact that dissolved oxygen absorbs ultraviolet light due to the photochemical effect, the water sample is delivered through a nitrogen sealed system which will prevent the sample from contacting with oxygen. A compassion of our absorption spectrum with other existing data is given.

  19. Protective Capacity and Absorptive Capacity: Managing the Balance between Retention and Creation of Knowledge-Based Resources

    ERIC Educational Resources Information Center

    Andersen, Jim

    2012-01-01

    Purpose: In order to understand the pros and cons of an open organization regarding the flow of knowledge between firms, this paper introduces the concept of "protective capacity". The purpose of the paper is to elaborate the concept of "protective capacity" especially in relation to absorptive capacity, by presenting a number of propositions.…

  20. Absorption type water chiller fired directly by waste heat

    NASA Astrophysics Data System (ADS)

    Sauer, K. L.; Kalwar, K.

    1982-08-01

    The direct use of waste heat as heating element in a water chiller of the absorption type was studied. The chilled water is used as cooling element in the industrial process, producing the waste heat or for conditioning the workplace or further located places. The heat source is gaseous or liquid. The cooling capacity is in the range from 10 to 120 kW. After reviewing the different absorption systems, LiBr/H20 proved to be the most suitable. The process retained for experimenting was the manufacturing of synthetic materials polymer industry and was tested in two different factories. It is proved that the use of absorption type water chillers is practicable with an efficiency of 10% to 25% of the waste heat energy, but that the existing chillers need extensive conversion for obtaining economical operation when using a low temperature heating source.

  1. Water-related absorption in fibrous diamonds

    NASA Astrophysics Data System (ADS)

    Zedgenizov, D. A.; Shiryaev, A. A.; Kagi, H.; Navon, O.

    2003-04-01

    Cubic and coated diamonds from several localities (Brasil, Canada, Yakutia) were investigated using spectroscopic techniques. Special emphasis was put on investigation of water-related features of transmission Infra-red and Raman spectra. Presence of molecular water is inferred from broad absorption bands in IR at 3420 and 1640 cm-1. These bands were observed in many of the investigated samples. It is likely that molecular water is present in microinclusions in liquid state, since no clear indications of solid H_2O (ice VI-VII, Kagi et al., 2000) were found. Comparison of absorption by HOH and OH vibrations shows that diamonds can be separated into two principal groups: those containing liquid water (direct proportionality of OH and HOH absorption) and those with stronger absorption by OH group. Fraction of diamonds in every group depends on their provenance. There might be positive correlation between internal pressure in microinclusions (determined using quartz barometer, Navon et al., 1988) and affiliation with diamonds containing liquid water. In many cases absorption by HOH vibration is considerably lower than absorption by hydroxyl (OH) group. This may be explained if OH groups are partially present in mineral and/or melt inclusions. This hypothesis is supported by following fact: in diamonds with strong absorption by silicates and other minerals shape and position of the OH band differs from that in diamonds with low absorption by minerals. Moreover, in Raman spectra of individual inclusions sometimes the broad band at 3100 cm-1 is observed. This band is OH-related. In some samples water distribution is not homogeneous. Central part of the diamond usually contains more water than outer parts, but this is not a general rule for all the samples. Water absorption usually correlated with absorption of other components (carbonates, silicates and others). At that fibrous diamonds with relatively high content of silicates are characterized by molecular water. OH

  2. High temperature measurement of water vapor absorption

    NASA Technical Reports Server (NTRS)

    Keefer, Dennis; Lewis, J. W. L.; Eskridge, Richard

    1985-01-01

    An investigation was undertaken to measure the absorption coefficient, at a wavelength of 10.6 microns, for mixtures of water vapor and a diluent gas at high temperature and pressure. The experimental concept was to create the desired conditions of temperature and pressure in a laser absorption wave, similar to that which would be created in a laser propulsion system. A simplified numerical model was developed to predict the characteristics of the absorption wave and to estimate the laser intensity threshold for initiation. A non-intrusive method for temperature measurement utilizing optical laser-beam deflection (OLD) and optical spark breakdown produced by an excimer laser, was thoroughly investigated and found suitable for the non-equilibrium conditions expected in the wave. Experiments were performed to verify the temperature measurement technique, to screen possible materials for surface initiation of the laser absorption wave and to attempt to initiate an absorption wave using the 1.5 kW carbon dioxide laser. The OLD technique was proven for air and for argon, but spark breakdown could not be produced in helium. It was not possible to initiate a laser absorption wave in mixtures of water and helium or water and argon using the 1.5 kW laser, a result which was consistent with the model prediction.

  3. Effect of water absorption on the mechanical properties of poly(3-hydroxybutyrate)/vegetable fiber composites

    NASA Astrophysics Data System (ADS)

    Marinho, Vithória A. D.; Carvalho, Laura H.; Canedo, Eduardo L.

    2015-05-01

    The present work studies the effect of water absorption on the performance of composites of poly(3-hydroxybutyrate) (PHB) - a fully biodegradable semi-crystalline thermoplastic obtained from renewable resources through low-impact biotechnological process, biocompatible and non-toxic - and vegetable fiber from the fruit (coconut) of babassu palm tree.Water resistance is an important characteristic of structural composites, that may exposed to rain and humid environments. Both water absorption capacity (water solubility in the material) and the rate of water absorption (controlled by the diffusivity of water in the material) are important parameters. However, water absorption per se may not be the most important characteristic, insofar as the performance and applications of the compounds. It is the effect of the water content on the ultimate properties that determine the suitability of the material for applications that involve prolonged exposure to water.PHB/babassu composites with 0-20% load were prepared in an internal mixer. Two different types of babassu fibers having two different article size ranges were compounded with PHB and test specimens molded by compression. The water absorption capacity and the kinetic constant of water absorption were measured in triplicate. Mechanical properties under tension were measured for dry and moist specimens with different amounts of absorbed water.Results indicate that the performance of the composites is comparable to that of the pure matrix. Water absorption capacity increases from 0.7% (pure PHB) to 4% (PHB/20% babassu), but the water diffusivity (4.10□8 cm2/s) was found to be virtually independent of the water absorption level. Water absorption results in moderate drop in elastic modulus (10-30% at saturation, according to fiber content) but has little effect on tensile strength and elongation at break. Fiber type and initial particle size do not have a significant effect on water absorption or mechanical properties.

  4. Preparation of hydrophilic luffa sponges and their water absorption performance.

    PubMed

    Liu, Zhi; Pan, Yanxiong; Shi, Kai; Wang, Weicai; Peng, Chao; Li, Wei; Sha, Di; Wang, Zhe; Ji, Xiangling

    2016-08-20

    Hydrophilic luffa sponges are prepared by grafting polymerization of acrylamide (AM) on luffa cylindrica and subsequent partial hydrolysis under alkaline conditions. Attenuated total reflection infrared spectroscopy is used to verify the composition of the grafted (luffa-g-PAM) and hydrolyzed (luffa-g-(PAM-co-PAANa)) samples. Alkalization conditions, including aqueous NaOH concentrations, alkalization temperature, and time, are studied extensively. Optimized conditions are then obtained. The grafting percentage (GP) of polyacrylamide increases with the feed ratios of [AM]/[OH] and [Ce]/[OH], reaction temperature, and time. Furthermore, the GP can reach up to 160%. Pristine, alkalized, grafted, and hydrolyzed luffa sponges show rapid absorption kinetics, and the pseudo second-order rate equation is applied to describe their kinetic procedure. Reaction conditions, such as [AM]/[OH], [Ce]/[OH], reaction temperature and time, influence the water absorption capacities of grafted and hydrolyzed samples. The hydrolyzed luffa sponges particularly exhibit high water absorption capacities of 75gg(-1). The absorption mechanism is also discussed.

  5. Water holding capacity in poultry breast meat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The underlying mechanisms that control water-holding capacity (WHC) in pale broiler meat are not well-established. The objectives of the two studies reported here were: 1) to determine the relationship between WHC and protein denaturation in broiler breast meat exhibiting divergent WHC attributes,...

  6. Vitamin B12 absorption capacity in healthy children

    SciTech Connect

    Hjelt, K.; Krasilnikoff, P.A.

    1986-03-01

    B12 absorption was investigated in 47 healthy children aged 7 months to 15.8 years (median 4.9 years). The patients had either recovered from giardiasis, the post-gastroenteritis syndrome, or had celiac disease in remission (treated with a gluten-free diet). The B12 absorption was measured by a double-isotope technique using /sup 57/CoB12 and /sup 51/CrCl/sub 3/, the latter being the inabsorbable marker. The radiation dose was minimal. The results were presented as fractional absorption of B12 (FAB12). Within the different age groups, the absorption test was performed by means of the following oral amounts of B12: 0- less than 1 year, 0.5 microgram; 1-3 years: 1.7 micrograms, 4-6 years, 2.5 micrograms; 7-10 years; 3.3 micrograms; and 11-15 years, 4.5 micrograms. When using these oral amounts of B12, the medians (and ranges) of FAB12 were found to be: 1-3 years (n = 18), 37% (16-80%); 4-6 years (n = 10), 27% (19-40%); 7-10 years (n = 9), 32% (21-44%); and 11-15 years (n = 8), 27% (19-59%). The FAB12 in two children aged 7 and 11 months was 31% and 32%, respectively. These results may be interpretated as reference values for B12 absorption in children. Further absorption tests were performed in seven children representing the four age groups from 1 to 15 years. When a high oral amount of B12 was given (i.e., three times the saturation dose), the FAB12 ranged from 0 to 20% (median 9%), whereas a low amount (i.e., one-ninth of the saturation dose) produced fractional absorptions from 65 to 82% (median 74%).

  7. Water storage capacity, stemflow and water funneling in Mediterranean shrubs

    NASA Astrophysics Data System (ADS)

    Garcia-Estringana, P.; Alonso-Blázquez, N.; Alegre, J.

    2010-08-01

    SummaryTo predict water losses and other hydrological and ecological features of a given vegetation, its water storage capacity and stemflow need to be accurately determined. Vast areas of the Mediterranean region are occupied by shrublands yet there is scarce data available on their rainwater interception capacity. In this study, simulated rainfall tests were conducted in controlled conditions on nine Mediterranean shrubs of varying anatomic and morphological features to determine water storage capacity, stemflow and the funneling ratio. After assessing correlations between these hydrological variables and the biometric characteristics of the shrubs, we compared two methods of determining storage capacity: rainfall simulation and immersion. Mean water storage capacity was 1.02 mm (0.35-3.24 mm), stemflow was 16% (3.8-26.4%) and the funneling ratio was 104 (30-260). Per unit biomass, mean storage capacity was 0.66 ml g -1 and ranged from 0.23 ml g -1 for Cistus ladanifer to 2.26 ml g -1 for Lavandula latifolia. Despite their small size, shrubs may generate high water losses to the atmosphere when they form dense communities and this can have a significant impact in regions where water is scarce. When considered the whole shrubs in absolute terms (ml per plant), water storage capacity and stemflow were correlated to biomass and the dendrometric characteristics of the shrubs, yet in relative terms (expressed per surface area unit or as %), anatomic features such as pubescence, branch rigidity or leaf insertion angle emerged as determining factors. The use of a simple procedure to assess storage capacity was inefficient. The immersion method underestimated storage capacity to a different extent for each species. Some shrubs returned high stemflow values typical of their adaptation to the semiarid climate. In contrast, other shrubs seem to have structures that promote stemflow yet have developed other drought-adaptation mechanisms. In this report, we discuss the

  8. Absorption coefficient instrument for turbid natural waters.

    PubMed

    Friedman, E; Poole, L; Cherdak, A; Houghton, W

    1980-05-15

    An instrument has been developed that directly measures the multispectral absorption coefficient of turbid natural water. The design incorporates methods for compensation of variation in the internal light source intensity, correction of the spectrally dependent nature of the optical elements, and correction for variation in background light level. When used in conjunction with a spectrally matched total attenuation instrument, the spectrally dependent scattering coefficient can also be derived. Systematic errors associated with multiple scattering have been estimated using Monte Carlo techniques.

  9. Monitoring Telluric Water Absorption with CAMAL

    NASA Astrophysics Data System (ADS)

    Baker, Ashley; Blake, Cullen; Sliski, David

    2017-01-01

    Ground-based observations are severely limited by telluric water vapor absorption features, which are highly variable in time and significantly complicate both spectroscopy and photometry in the near-infrared (NIR). To achieve the stability required to study Earth-sized exoplanets, monitoring the precipitable water vapor (PWV) becomes necessary to mitigate the impact of telluric lines on radial velocity measurements and transit light curves. To address this issue, we present the Camera for the Automatic Monitoring of Atmospheric Lines (CAMAL), a stand-alone, inexpensive 6-inch aperture telescope dedicated to measuring PWV at the Whipple Observatory. CAMAL utilizes three NIR narrowband filters to trace the amount of atmospheric water vapor affecting simultaneous observations with the MINiature Exoplanet Radial Velocity Array (MINERVA) and MINERVA-Red telescopes. We present the current design of CAMAL, discuss our calibration methods, and show PWV measurements taken with CAMAL compared to those of a nearby GPS water vapor monitor.

  10. Shock absorption capacities of mouthguards in different types and thicknesses.

    PubMed

    Bemelmanns, P; Pfeiffer, P

    2001-02-01

    Although sports mouthguards provide protection against trauma, dentoalveolar injuries can still occur with the mouthguards in place. This study examined the effect of mouthguard protection in an in vitro model. A simulated maxilla, out of a polymethylmethacrylate (PMMA) arch, containing replaceable resin teeth, was used to assess the performance of different mouthguard designs. "Boil and bite" and custom-fitted mouthguards (ethylene vinyl acetate [EVA]) laminated with hard (poly-vinyl chloride [PVC]) or soft labial intermediate EVA layers were fabricated according to manufacturers' instructions. A steel ram was dropped onto the mouthguards at the maxillary incisor region. Changes in voltage, which were induced by a strain gauge at the back of the upper left incisor, were measured with an amplified voltmeter. Data were analysed by ANOVA at a significance level of 0.05. "Boil and bite" and mouthguards layered with silicone or with small hard PVC inserts of 1.5 mm thickness demonstrated less absorption and differed significantly from the other mouthguard systems (p < 0.05). Bilaminated mouthguards with hard PVC inserts of 0.8 mm, 1.5 mm or 2 mm thickness showed no significant differences to those with 1.5 mm thick (EVA) inserts. The absorption rates amounted to 33 % compared with the unprotected tooth.

  11. Absorption coefficient instrument for turbid natural waters

    NASA Astrophysics Data System (ADS)

    Friedman, E.; Cherdak, A.; Poole, L.; Houghton, W.

    1980-05-01

    The paper presents an instrument that directly measures multispectral absorption coefficient of turbid natural water. Attention is given to the design, which is shown to incorporate methods for the compensation of variation in the internal light source intensity, correction of the spectrally dependent nature of the optical elements, and correction for variation in the background light level. In addition, when used in conjunction with a spectrally matched total attenuation instrument, the spectrally dependent scattering coefficient can also be derived. Finally, it is reported that systematic errors associated with multiple scattering have been estimated using Monte Carlo techniques.

  12. Absorption coefficient instrument for turbid natural waters

    NASA Technical Reports Server (NTRS)

    Friedman, E.; Cherdak, A.; Poole, L.; Houghton, W.

    1980-01-01

    The paper presents an instrument that directly measures multispectral absorption coefficient of turbid natural water. Attention is given to the design, which is shown to incorporate methods for the compensation of variation in the internal light source intensity, correction of the spectrally dependent nature of the optical elements, and correction for variation in the background light level. In addition, when used in conjunction with a spectrally matched total attenuation instrument, the spectrally dependent scattering coefficient can also be derived. Finally, it is reported that systematic errors associated with multiple scattering have been estimated using Monte Carlo techniques.

  13. Anomalous atmospheric absorption spectra due to water dimer

    NASA Astrophysics Data System (ADS)

    Cai, Peipei; Zhang, Hansheng; Shen, Shanxiong; Cheng, I.-Shan

    1986-11-01

    The anomalous atmospheric absorption spectra in the window wavelength region of 8-14 microns have been suggested due to the water dimer. Based on laboratory measurements, water continuum CO2 laser absorption spectra and a resonance absorption line due to the weak local wave vapor pure rotational transition have been reported. The equilibrium concentration of water dimers in the atmosphere, the electronic binding energy and the theoretical calculations for absorption attenuation have been obtained in agreement with published data.

  14. 49 CFR 179.201-10 - Water capacity marking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Water capacity marking. 179.201-10 Section 179.201... Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.201-10 Water capacity marking. (a) Water capacity of the tank in pounds stamped plainly and permanently in letters and figures...

  15. 49 CFR 179.201-10 - Water capacity marking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Water capacity marking. 179.201-10 Section 179.201... Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.201-10 Water capacity marking. (a) Water capacity of the tank in pounds stamped plainly and permanently in letters and figures...

  16. 49 CFR 179.201-10 - Water capacity marking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Water capacity marking. 179.201-10 Section 179.201... Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.201-10 Water capacity marking. (a) Water capacity of the tank in pounds stamped plainly and permanently in letters and figures...

  17. 49 CFR 179.201-10 - Water capacity marking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Water capacity marking. 179.201-10 Section 179.201... Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.201-10 Water capacity marking. (a) Water capacity of the tank in pounds stamped plainly and permanently in letters and figures...

  18. Water addition, evaporation and water holding capacity of poultry litter.

    PubMed

    Dunlop, Mark W; Blackall, Patrick J; Stuetz, Richard M

    2015-12-15

    Litter moisture content has been related to ammonia, dust and odour emissions as well as bird health and welfare. Improved understanding of the water holding properties of poultry litter as well as water additions to litter and evaporation from litter will contribute to improved litter moisture management during the meat chicken grow-out. The purpose of this paper is to demonstrate how management and environmental conditions over the course of a grow-out affect the volume of water A) applied to litter, B) able to be stored in litter, and C) evaporated from litter on a daily basis. The same unit of measurement has been used to enable direct comparison-litres of water per square metre of poultry shed floor area, L/m(2), assuming a litter depth of 5cm. An equation was developed to estimate the amount of water added to litter from bird excretion and drinking spillage, which are sources of regular water application to the litter. Using this equation showed that water applied to litter from these sources changes over the course of a grow-out, and can be as much as 3.2L/m(2)/day. Over a 56day grow-out, the total quantity of water added to the litter was estimated to be 104L/m(2). Litter porosity, water holding capacity and water evaporation rates from litter were measured experimentally. Litter porosity decreased and water holding capacity increased over the course of a grow-out due to manure addition. Water evaporation rates at 25°C and 50% relative humidity ranged from 0.5 to 10L/m(2)/day. Evaporation rates increased with litter moisture content and air speed. Maintaining dry litter at the peak of a grow-out is likely to be challenging because evaporation rates from dry litter may be insufficient to remove the quantity of water added to the litter on a daily basis.

  19. Optimum hot water temperature for absorption solar cooling

    SciTech Connect

    Lecuona, A.; Ventas, R.; Venegas, M.; Salgado, R.; Zacarias, A.

    2009-10-15

    The hot water temperature that maximizes the overall instantaneous efficiency of a solar cooling facility is determined. A modified characteristic equation model is used and applied to single-effect lithium bromide-water absorption chillers. This model is based on the characteristic temperature difference and serves to empirically calculate the performance of real chillers. This paper provides an explicit equation for the optimum temperature of vapor generation, in terms of only the external temperatures of the chiller. The additional data required are the four performance parameters of the chiller and essentially a modified stagnation temperature from the detailed model of the thermal collector operation. This paper presents and discusses the results for small capacity machines for air conditioning of homes and small buildings. The discussion highlights the influence of the relevant parameters. (author)

  20. Transient absorption of vibrationally excited water

    NASA Astrophysics Data System (ADS)

    Bakker, H. J.; Nienhuys, H.-K.; Gallot, G.; Lascoux, N.; Gale, G. M.; Leicknam, J.-C.; Bratos, S.

    2002-02-01

    We study the spectral response of the transition between the first and the second excited state of the O-H stretch vibration of HDO dissolved in liquid D2O with two-color femtosecond mid-infrared spectroscopy. The spectral response of this transition differs strongly from the fundamental absorption spectrum of the O-H stretch vibration. In addition, excitation of the O-H stretch vibration is observed to lead to a change of the hydrogen-bond dynamics of liquid water. We show that both these observations can be described with a refined quantum-mechanical version of the Lippincott-Schroeder model for hydrogen-bonded OH⋯O systems.

  1. Antecedents of Absorptive Capacity: A New Model for Developing Learning Processes

    ERIC Educational Resources Information Center

    Rezaei-Zadeh, Mohammad; Darwish, Tamer K.

    2016-01-01

    Purpose: The purpose of this paper is to provide an integrated framework to indicate which antecedents of absorptive capacity (AC) influence its learning processes, and to propose testing of this model in future work. Design/methodology/approach Relevant literature into the antecedents of AC was critically reviewed and analysed with the objective…

  2. Developing and Validating Field Measurement Scales for Absorptive Capacity and Experienced Community of Practice

    ERIC Educational Resources Information Center

    Cadiz, David; Sawyer, John E.; Griffith, Terri L.

    2009-01-01

    Research on knowledge transfer in organizations has been hampered by the lack of tools yielding valid scores for studying critical constructs in concert. The authors developed survey measures of absorptive capacity (the ability to transform new knowledge into usable knowledge) and experienced community of practice (the extent to which a person is…

  3. The Effect of Absorptive Capacity Perceptions on the Context Aware Ubiquitous Learning Acceptance

    ERIC Educational Resources Information Center

    Lin, Hsiu-Fen

    2013-01-01

    Purpose: The purpose of this study is to examine the impact of absorptive capacity (understanding, assimilating and applying u-learning) perceptions on behavioral intention to use u-learning through path analysis and applies the technology acceptance model (TAM) as a theoretical foundation, simultaneously improving the model by adopting prior…

  4. Water-lithium bromide double-effect absorption cooling analysis. Final report

    SciTech Connect

    Vliet, G.C.; Lawson, M.B.; Lithgow, R.A.

    1980-12-01

    This investigation involved the development of a numerical model for the transient simulation of the double-effect, water-lithium bromide absorption cooling machine, and the use of the model to determine the effect of the various design and input variables on the absorption unit performance. The performance parameters considered were coefficient of performance and cooling capacity. The sensitivity analysis was performed by selecting a nominal condition and determining performance sensitivity for each variable with others held constant. The variables considered in the study include source hot water, cooling water, and chilled water temperatures; source hot water, cooling water, and chilled water flow rates; solution circulation rate; heat exchanger areas; pressure drop between evaporator and absorber; solution pump characteristics; and refrigerant flow control methods. The performance sensitivity study indicated in particular that the distribution of heat exchanger area among the various (seven) heat exchange components is a very important design consideration. Moreover, it indicated that the method of flow control of the first effect refrigerant vapor through the second effect is a critical design feature when absorption units operate over a significant range of cooling capacity. The model was used to predict the performance of the Trane absorption unit with fairly good accuracy. The dynamic model should be valuable as a design tool for developing new absorption machines or modifying current machines to make them optimal based on current and future energy costs.

  5. Temperature effects on dynamic water absorption into paper.

    PubMed

    Songok, Joel; Salminen, Pekka; Toivakka, Martti

    2014-03-15

    Mechanisms controlling short time water absorption and the effect of temperature on water absorption into paper were investigated by analyzing previously published data. A dynamic contact angle effect caused by contact line friction explained the liquid uptake dynamics at short times. The water absorption rate increase with temperature is suggested to be controlled by the molecular processes occurring in front of the advancing liquid front. The increase in the non-equilibrium vapor pressure at air-liquid interface leads to higher water molecule adsorption onto fibers and associated lowering of the solid-gas interfacial tension, thereby increasing the wetting velocity and water absorption. The classical Lucas-Washburn equation was found to be inadequate for predicting water absorption into paper both at short times and as a function of temperature.

  6. Effect of water absorption on pollen adhesion.

    PubMed

    Lin, Haisheng; Lizarraga, Leonardo; Bottomley, Lawrence A; Carson Meredith, J

    2015-03-15

    Pollens possess a thin liquid coating, pollenkitt, which plays a major role in adhesion by forming capillary menisci at interfaces. Unfortunately, the influence of humidity on pollenkitt properties and capillary adhesion is unknown. Because humidity varies widely in the environment, the answers have important implications for better understanding plant reproduction, allergy and asthma, and pollen as atmospheric condensation nuclei. Here, pollenkitt-mediated adhesion of sunflower pollen to hydrophilic and hydrophobic surfaces was measured as a function of humidity. The results quantify for the first time the significant water absorption of pollenkitt and the resulting complex dependence of adhesion on humidity. On hydrophilic Si, adhesion increased with increasing RH for pollens with or without pollenkitt, up to 200nN at 70% RH. In contrast, on hydrophobic PS, adhesion of pollenkitt-free pollen is independent of RH. Surprisingly, when pollenkitt was present adhesion forces on hydrophobic PS first increased with RH up to a maximum value at 35% RH (∼160nN), and then decreased with further increases in RH. Independent measurement of pollenkitt properties is used with models of capillary adhesion to show that humidity-dependent changes in pollenkitt wetting and viscosity are responsible for this complex adhesion behavior.

  7. Water absorption properties of ultrasonic treated brown rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To understand the effect of ultrasonic treated on brown rice, it is important to research the water absorption processing of brown rice before and after ultrasonic treatment. The objective of this study was investigate and modeling water absorption characteristics of brown rice using Peleg’s equatio...

  8. The heat capacity of water near solid surfaces

    NASA Astrophysics Data System (ADS)

    Vučelić, V.; Vučelić, D.

    1983-11-01

    Anomalous heat capacities of water at solid/water interfaces have been obtained. The solids vary from inorganic (zeolites, porous class, silica gel, activated carbon) to biological (protein lysozyme and adrenal gland). Water heat capacities at all interfaces exhibit the same pattern. At room temperature the small values are close to ice and increase with temperature, reaching the value of free water between 380 and 440 K.

  9. New constraints in absorptive capacity and the optimum rate of petroleum output

    SciTech Connect

    El Mallakh, R

    1980-01-01

    Economic policy in four oil-producing countries is analyzed within a framework that combines a qualitative assessment of the policy-making process with an empirical formulation based on historical and current trends in these countries. The concept of absorptive capacity is used to analyze the optimum rates of petroleum production in Iran, Iraq, Saudi Arabia, and Kuwait. A control solution with an econometric model is developed which is then modified for alternative development strategies based on analysis of factors influencing production decisions. The study shows the consistencies and inconsistencies between the goals of economic growth, oil production, and exports, and the constraints on economic development. Simulation experiments incorporated a number of the constraints on absorptive capacity. Impact of other constraints such as income distribution and political stability is considered qualitatively. (DLC)

  10. Absorption-Edge-Modulated Transmission Spectra for Water Contaminant Monitoring

    DTIC Science & Technology

    2016-03-31

    Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6390--16-9675 Absorption-Edge-Modulated Transmission Spectra for Water Contaminant...ABSTRACT c. THIS PAGE 18. NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Absorption-Edge-Modulated Transmission Spectra for Water Contaminant Monitoring...Unlimited Unclassified Unlimited 35 Samuel G. Lambrakos (202) 767-2601 Monitoring of contaminants associated with specific water resources using

  11. Economic performance of water storage capacity expansion for food security

    NASA Astrophysics Data System (ADS)

    Gohar, Abdelaziz A.; Ward, Frank A.; Amer, Saud A.

    2013-03-01

    SummaryContinued climate variability, population growth, and rising food prices present ongoing challenges for achieving food and water security in poor countries that lack adequate water infrastructure. Undeveloped storage infrastructure presents a special challenge in northern Afghanistan, where food security is undermined by highly variable water supplies, inefficient water allocation rules, and a damaged irrigation system due three decades of war and conflict. Little peer-reviewed research to date has analyzed the economic benefits of water storage capacity expansions as a mechanism to sustain food security over long periods of variable climate and growing food demands needed to feed growing populations. This paper develops and applies an integrated water resources management framework that analyzes impacts of storage capacity expansions for sustaining farm income and food security in the face of highly fluctuating water supplies. Findings illustrate that in Afghanistan's Balkh Basin, total farm income and food security from crop irrigation increase, but at a declining rate as water storage capacity increases from zero to an amount equal to six times the basin's long term water supply. Total farm income increases by 21%, 41%, and 42% for small, medium, and large reservoir capacity, respectively, compared to the existing irrigation system unassisted by reservoir storage capacity. Results provide a framework to target water infrastructure investments that improve food security for river basins in the world's dry regions with low existing storage capacity that face ongoing climate variability and increased demands for food security for growing populations.

  12. Cycle Simulation of HotWater Fired Absorption Chiller

    NASA Astrophysics Data System (ADS)

    Esaki, Shuji; Iramina, Kazuyasu; Kobayashi, Takahiro; Ohnou, Masayuki; Kaneko, Toshiyuki; Soga, Takashi

    The design limits were examined to determine the lowest temperature for hot water that can be used as a heat source to drive a hot water fired absorption chiller. Advantage was taken of the fact that the cycle calculation method using the minimum temperature difference is quite effective. This minimum temperature difference was the lower of the two temperature differences used to get the logarithmic mean temperature difference that need to design the evaporator, absorber, condenser and generator in an absorption refrigerator. This report proposes a new solution algorithm employing this minimum temperature difference to make a cycle simulation of the hot water fired absorption chiller. It shows the lowest usable temperature for hot water and makes clear the chilled water and cooling water temperature conditions that can provide the lowest temperature.

  13. Measured performance of a 3-ton LiBr absorption water chiller and its effect on cooling system operation

    NASA Technical Reports Server (NTRS)

    Namkoong, D.

    1976-01-01

    A 3-ton lithium bromide absorption water chiller was tested for a number of conditions involving hot-water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It is concluded that a 3-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  14. Measured performance of a 3 ton LiBr absorption water chiller and its effect on cooling system operation

    NASA Technical Reports Server (NTRS)

    Namkoong, D.

    1976-01-01

    A three ton lithium bromide absorption water chiller was tested for a number of conditions involving hot water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It was concluded that a three-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  15. Absorption of water and lubricating oils into porous nylon

    NASA Technical Reports Server (NTRS)

    Bertrand, P. A.

    1995-01-01

    Oil and water absorption from air into sintered porous nylon can be described by infiltration into the pores of the material. This process can be modeled by a diffusion-like mechanism. For water absorption, we find a formal diffusion coefficient of 1.5 x 10(exp -4)sq cm/min when the nylon is initially dry. The diffusion coefficient is 4 x 10(exp -6)sq cm/min when the nylon is oil-impregnated prior to air exposure. In a 52% RH atmosphere, dry nylon absorbs 3% w/w water, and oil-impregnated nylon absorbs 0.6% w/w water. For oil absorption there are three steps: (1) surface absorption and infiltration into (2) larger and (3) smaller pores. Surface absorption is too fast to be measured in these experiments. The diffusion coefficient for the second step is 6 x 10(exp -4)sq cm/min for SRG-60 oil into dry nylon and 4 x 10(exp -4)sq cm/min for air-equilibrated nylon. The diffusion coefficient for the third step is about 1 x 10(exp -6)sq cm/min for both cases. The total amount of oil absorbed is 31% w/w. The interaction between water and nylon is not as strong as that between water and cotton-phenolic: oil can replace water, and only a small amount of water can enter previously oil-impregnated nylon.

  16. Water vapor absorption of carbon dioxide laser radiation

    NASA Technical Reports Server (NTRS)

    Shumate, M. S.; Menzies, R. T.; Margolis, J. S.; Rosengren, L.-G.

    1976-01-01

    An optoacoustic detector or spectrophone has been used to perform detailed measurements of the absorptivity of mixtures of water vapor in air. A (C-12) (O-16)2 laser was used as the source, and measurements were made at forty-nine different wavelengths from 9.2 to 10.7 microns. The details of the optoacoustic detector and its calibration are presented, along with a discussion of its performance characteristics. The results of the measurements of water vapor absorption show that the continuum absorption in the wavelength range covered is 5-10% lower than previous measurements.

  17. 30 CFR 75.1107-7 - Water spray devices; capacity; water supply; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Water spray devices; capacity; water supply; minimum requirements. (a) Where water spray devices are... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Water spray devices; capacity; water supply; minimum requirements. 75.1107-7 Section 75.1107-7 Mineral Resources MINE SAFETY AND HEALTH...

  18. Predicting and mapping soil available water capacity in Korea

    PubMed Central

    Hong, Suk Young; Han, Kyung Hwa; Kim, Yihyun; Lee, Kyungdo

    2013-01-01

    The knowledge on the spatial distribution of soil available water capacity at a regional or national extent is essential, as soil water capacity is a component of the water and energy balances in the terrestrial ecosystem. It controls the evapotranspiration rate, and has a major impact on climate. This paper demonstrates a protocol for mapping soil available water capacity in South Korea at a fine scale using data available from surveys. The procedures combined digital soil mapping technology with the available soil map of 1:25,000. We used the modal profile data from the Taxonomical Classification of Korean Soils. The data consist of profile description along with physical and chemical analysis for the modal profiles of the 380 soil series. However not all soil samples have measured bulk density and water content at −10 and −1500 kPa. Thus they need to be predicted using pedotransfer functions. Furthermore, water content at −10 kPa was measured using ground samples. Thus a correction factor is derived to take into account the effect of bulk density. Results showed that Andisols has the highest mean water storage capacity, followed by Entisols and Inceptisols which have loamy texture. The lowest water retention is Entisols which are dominated by sandy materials. Profile available water capacity to a depth of 1 m was calculated and mapped for Korea. The western part of the country shows higher available water capacity than the eastern part which is mountainous and has shallower soils. The highest water storage capacity soils are the Ultisols and Alfisols (mean of 206 and 205 mm, respectively). Validation of the maps showed promising results. The map produced can be used as an indication of soil physical quality of Korean soils. PMID:23646290

  19. Absorptive removal of biomass tar using water and oily materials.

    PubMed

    Phuphuakrat, Thana; Namioka, Tomoaki; Yoshikawa, Kunio

    2011-01-01

    Water is the most common choice of absorption medium selected in many gasification systems. Because of poor solubility of tar in water, hydrophobic absorbents (diesel fuel, biodiesel fuel, vegetable oil, and engine oil) were studied on their absorption efficiency of biomass tar and compared with water. The results showed that only 31.8% of gravimetric tar was removed by the water scrubber, whereas the highest removal of gravimetric tar was obtained by a vegetable oil scrubber with a removal efficiency of 60.4%. When focusing on light PAH tar removal, the absorption efficiency can be ranked in the following order; diesel fuel>vegetable oil>biodiesel fuel>engine oil>water. On the other hand, an increase in gravimetric tar was observed for diesel fuel and biodiesel fuel scrubbers because of their easy evaporation. Therefore, the vegetable oil is recommended as the best absorbent to be used in gasification systems.

  20. Heat capacity and thermal expansion of water and helium

    NASA Astrophysics Data System (ADS)

    Putintsev, N. M.; Putintsev, D. N.

    2017-04-01

    Original expressions for heat capacity CV and its components, vibrational and configurational components of thermal expansion coefficient were established. The values of CV, Cvib, Cconf, αvib and αconf for water and helium 4He were calculated.

  1. The moderating role of absorptive capacity and the differential effects of acquisitions and alliances on Big Pharma firms' innovation performance

    PubMed Central

    Fernald, K. D. S.; Pennings, H. P. G.; van den Bosch, J. F.; Commandeur, H. R.; Claassen, E.

    2017-01-01

    In the context of increased pharmaceutical innovation deficits and Big Pharma blockbusters’ patent expirations, this paper examines the moderating role of firms’ absorptive capacity in external innovation activities of Big Pharma firms. The study indicates a rising interest of Big Pharma in acquisitions of and alliances with biotechnology companies. Unfortunately, this increased interest is not reflected in the number of new drugs generated by Big Pharma. We find that acquisitions of biotech companies have negatively affected Big Pharma firms’ innovation performance on average but these acquisitions might have a positive effect at higher levels of acquiring firms’ absorptive capacity. Moreover, also acquisitions of pharma companies and alliances with biotech companies only have a positive effect on innovation performance at sufficiently high levels of absorptive capacity. The moderating role of absorptive capacity implicates that a tight integration of internal R&D efforts and (unrelated) external knowledge is crucial for harnessing complementarity effects. PMID:28231332

  2. The moderating role of absorptive capacity and the differential effects of acquisitions and alliances on Big Pharma firms' innovation performance.

    PubMed

    Fernald, K D S; Pennings, H P G; van den Bosch, J F; Commandeur, H R; Claassen, E

    2017-01-01

    In the context of increased pharmaceutical innovation deficits and Big Pharma blockbusters' patent expirations, this paper examines the moderating role of firms' absorptive capacity in external innovation activities of Big Pharma firms. The study indicates a rising interest of Big Pharma in acquisitions of and alliances with biotechnology companies. Unfortunately, this increased interest is not reflected in the number of new drugs generated by Big Pharma. We find that acquisitions of biotech companies have negatively affected Big Pharma firms' innovation performance on average but these acquisitions might have a positive effect at higher levels of acquiring firms' absorptive capacity. Moreover, also acquisitions of pharma companies and alliances with biotech companies only have a positive effect on innovation performance at sufficiently high levels of absorptive capacity. The moderating role of absorptive capacity implicates that a tight integration of internal R&D efforts and (unrelated) external knowledge is crucial for harnessing complementarity effects.

  3. Field demonstration of the combined effects of absorption and evapotranspiration on septic system drainfield capacity.

    PubMed

    Rainwater, Ken; Jackson, Andrew; Ingram, Wesley; Lee, Chang Yong; Thompson, David; Mollhagen, Tony; Ramsey, Heyward; Urban, Lloyd

    2005-01-01

    Drainfields for disposal of septic tank effluents are typically designed by considering the loss of water by either upward evapotranspiration into the atmosphere or lateral and downward absorption into the adjacent soil. While this approach is appropriate for evapotranspiration systems, absorption systems allow water loss by both mechanisms. It was proposed that, in areas where high evapotranspiration rates coincide with permeable soils, drainfield sizes could be substantially reduced by accounting for both mechanisms. A two-year field demonstration was conducted to determine appropriate design criteria for areas typical of the Texas High Plains. The study consisted of evaluating the long-term acceptance rates for three different drainfield configurations: evapotranspiration only, absorption only, and combined conditions. A second field demonstration repeated the experiments for additional observation of the combined evapotranspiration and absorption and achieved similar results as the first study. The field tests indicated that the current design loading criteria may be increased by at least a factor of two for the Texas High Plains region and other Texas areas with similar soil composition and evapotranspiration rates, while still retaining a factor of safety of two.

  4. Measurement of atmospheric precipitable water using a solar radiometer. [water vapor absorption effects

    NASA Technical Reports Server (NTRS)

    Pitts, D. E.; Dillinger, A. E.; Mcallum, W. E.

    1974-01-01

    A technique is described and tested that allows the determination of atmospheric precipitable water from two measurements of solar intensity: one in a water-vapor absorption band and another in a nearby spectral region unaffected by water vapor.

  5. In vivo measurement of the absorption of strontium in the rumen and small intestine of sheep as an index of calcium absorption capacity.

    PubMed

    Hyde, Michelle L; Fraser, David R

    2014-09-14

    In the present study, a method was developed for determining the alimentary tract Ca absorption capacity of ruminant animals by measuring the absorption rate of Sr after the administration of an oral dose of strontium chloride acting as a tracer analogue of Ca. A close correlation between the absorption rates of the two tracers was observed upon simultaneous administration of an oral dose of stable Sr and radioactive calcium (r 0·98). The Ca absorption capacity of the rumen and small intestine was determined separately by either directing the solution into the rumen or by diverting it into the post-ruminal tract by vasopressin-induced closure of the ruminoreticular groove. The animals were treated with 1α-hydroxyvitamin D3 administered via subcutaneously implanted mini-osmotic pumps. The effect of elevated plasma 1,25-dihydroxycholecalciferol concentrations on the Ca absorption capacity of the alimentary tract was then determined. An increased rate of Sr absorption was observed in both the rumen and small intestine of sheep after treatment, although it is unclear whether the rumen possesses the same vitamin D-dependent Ca absorption pathway as the small intestine.

  6. Proposed human stratum corneum water domain in chemical absorption.

    PubMed

    Zhu, Hanjiang; Jung, Eui-Chang; Hui, Xiaoying; Maibach, Howard

    2016-08-01

    Compounds with varying physical and chemical properties may have different affinities to the stratum corneum (SC) and/or its intercellular lipids, keratin protein, and possible water domains. To better understand the mechanism of percutaneous absorption, we utilized 21 carbon-14 labeled chemicals, with wide hydrophilicity (log P = -0.05 to 6.17), and quantified their absorption/adsorption properties for a short incubation time (15 min) with regards to intact SC membrane, delipidized SC membrane and SC lipid. A facile method was developed for SC/lipid absorption, providing a more equivalent procedure and comparable data. SC lipid absorption of chemical solutes positively correlated with the octanol/water partition coefficient (log P). Differences between the percent dose of chemical absorption to intact SC and the total percent dose contributed by the protein and lipid domains suggest the possibility and significance of a water domain. Absorption rate experiments showed a longer lag time for intact SC than for delipidized SC or SC lipid, suggesting that the water domain may delay chemical binding to protein and lipid domains, and may be a factor in the resistance of many chemicals to current decontamination methods. Copyright © 2015 John Wiley & Sons, Ltd.

  7. A polydimethylsiloxane (PDMS) sponge for the selective absorption of oil from water.

    PubMed

    Choi, Sung-Jin; Kwon, Tae-Hong; Im, Hwon; Moon, Dong-Il; Baek, David J; Seol, Myeong-Lok; Duarte, Juan P; Choi, Yang-Kyu

    2011-12-01

    We present a sugar-templated polydimethylsiloxane (PDMS) sponge for the selective absorption of oil from water. The process for fabricating the PDMS sponge does not require any intricate synthesis processes or equipment and it is not environmentally hazardous, thus promoting potential in environmental applications. The proposed PDMS sponge can be elastically deformed into any shape, and it can be compressed repeatedly in air or liquids without collapsing. Therefore, absorbed oils and organic solvents can be readily removed and reused by simply squeezing the PDMS sponge, enabling excellent recyclability. Furthermore, through appropriately combining various sugar particles, the absorption capacity of the PDMS sponge is favorably optimized.

  8. Heat capacity of water: A signature of nuclear quantum effects

    NASA Astrophysics Data System (ADS)

    Vega, C.; Conde, M. M.; McBride, C.; Abascal, J. L. F.; Noya, E. G.; Ramirez, R.; Sesé, L. M.

    2010-01-01

    In this note we present results for the heat capacity at constant pressure for the TIP4PQ/2005 model, as obtained from path-integral simulations. The model does a rather good job of describing both the heat capacity of ice Ih and of liquid water. Classical simulations using the TIP4P/2005, TIP3P, TIP4P, TIP4P-Ew, simple point charge/extended, and TIP5P models are unable to reproduce the heat capacity of water. Given that classical simulations do not satisfy the third law of thermodynamics, one would expect such a failure at low temperatures. However, it seems that for water, nuclear quantum effects influence the heat capacities all the way up to room temperature. The failure of classical simulations to reproduce Cp points to the necessity of incorporating nuclear quantum effects to describe this property accurately.

  9. Global distribution of plant-extractable water capacity of soil

    USGS Publications Warehouse

    Dunne, K.A.; Willmott, C.J.

    1996-01-01

    Plant-extractable water capacity of soil is the amount of water that can be extracted from the soil to fulfill evapotranspiration demands. It is often assumed to be spatially invariant in large-scale computations of the soil-water balance. Empirical evidence, however, suggests that this assumption is incorrect. In this paper, we estimate the global distribution of the plant-extractable water capacity of soil. A representative soil profile, characterized by horizon (layer) particle size data and thickness, was created for each soil unit mapped by FAO (Food and Agriculture Organization of the United Nations)/Unesco. Soil organic matter was estimated empirically from climate data. Plant rooting depths and ground coverages were obtained from a vegetation characteristic data set. At each 0.5?? ?? 0.5?? grid cell where vegetation is present, unit available water capacity (cm water per cm soil) was estimated from the sand, clay, and organic content of each profile horizon, and integrated over horizon thickness. Summation of the integrated values over the lesser of profile depth and root depth produced an estimate of the plant-extractable water capacity of soil. The global average of the estimated plant-extractable water capacities of soil is 8??6 cm (Greenland, Antarctica and bare soil areas excluded). Estimates are less than 5, 10 and 15 cm - over approximately 30, 60, and 89 per cent of the area, respectively. Estimates reflect the combined effects of soil texture, soil organic content, and plant root depth or profile depth. The most influential and uncertain parameter is the depth over which the plant-extractable water capacity of soil is computed, which is usually limited by root depth. Soil texture exerts a lesser, but still substantial, influence. Organic content, except where concentrations are very high, has relatively little effect.

  10. Absorption of impinging water droplet in porous stones.

    PubMed

    Lee, J B; Radu, A I; Vontobel, P; Derome, D; Carmeliet, J

    2016-06-01

    This paper presents an experimental investigation and numerical analysis of the absorption of water droplets impacting porous stones. The absorption process of an impinging droplet is here fully characterized from spreading to evaporation in terms of absorbed mass during droplet depletion and moisture content distribution in a time-resolved manner for three different natural stones. High-speed imaging and neutron radiography are used to quantify moisture absorption in porous stones of varying moisture properties from deposition until depletion. During impact and spreading, the droplet exhibits a dynamic non-wetting behavior. At maximum spreading, the droplet undergoes pinning, resulting into the contact radius remaining constant until droplet depletion. Absorption undergoes two phases: initially, absorption is hindered due a contact resistance attributed to entrapped air; afterwards, a more perfect capillary contact occurs and absorption goes on until depletion, concurrently with evaporation and further redistribution. A finite-element numerical model for isothermal unsaturated moisture transport in porous media captures the phases of mass absorption in good agreement with the experimental data. Droplet spreading and absorption are highly determined by the impact velocity of the droplet, while moisture content redistribution after depletion is much less dependent on impact conditions.

  11. Scramjet Performance Assessment Using Water Absorption Diagnostics (U)

    NASA Technical Reports Server (NTRS)

    Cavolowsky, John A.; Loomis, Mark P.; Deiwert, George

    1995-01-01

    Simultaneous multiple path measurements of temperature and H2O concentration will be presented for the AIMHYE test entries in the NASA Ames 16-Inch Shock Tunnel. Monitoring the progress of high temperature chemical reactions that define scramjet combustor efficiencies is a task uniquely suited to nonintrusive optical diagnostics. One application strategy to overcome the many challenges and limitations of nonintrusive measurements is to use laser absorption spectroscopy coupled with optical fibers. Absorption spectroscopic techniques with rapidly tunable lasers are capable of making simultaneous measurements of mole fraction, temperature, pressure, and velocity. The scramjet water absorption diagnostic was used to measure combustor efficiency and was compared to thrust measurements using a nozzle force balance and integrated nozzle pressures to develop a direct technique for evaluating integrated scramjet performance. Tests were initially performed with a diode laser tuning over a water absorption feature at 1391.7 nm. A second diode laser later became available at a wavelength near 1343.3 nm covering an additional water absorption feature and was incorporated in the system for a two-wavelength technique. Both temperature and mole fraction can be inferred from the lineshape analysis using this approach. Additional high temperature spectroscopy research was conducted to reduce uncertainties in the scramjet application. The lasers are optical fiber coupled to ports at the combustor exit and in the nozzle region. The output from the two diode lasers were combined in a single fiber, and the resultant two-wavelength beam was subsequently split into four legs. Each leg was directed through 60 meters of optical fiber to four combustor exit locations for measurement of beam intensity after absorption by the water within the flow. Absorption results will be compared to 1D combustor analysis using RJPA and nozzle CFD computations as well as to data from a nozzle metric

  12. Sound absorption and concentration fluctuations in water-propanol mixtures

    NASA Astrophysics Data System (ADS)

    Madigosky, W. M.; Warfield, R. W.

    1987-02-01

    The excess ultrasonic sound absorption in 1-propanol water mixtures has been measured from 45 kHz to 474 MHz and is shown to result from a coupling of the sound wave with the long-wavelength spectrum of the composition fluctuations. The results are shown to be in agreement with the fluctuation theories of Fixman, Romanov and Solovyev, and Kawasaki and the more recent theories of Kroll and Ruhland, and Bhattacharjee and Ferrell. It is further suggested that the large absorption observed in alcohol-water mixtures may be due to the presence of large associated groups, or clusters.

  13. [Measuring water ecological carrying capacity with the ecosystem-service-based ecological footprint (ESEF) method: Theory, models and application].

    PubMed

    Jiao, Wen-jun; Min, Qing-wen; Li, Wen-hua; Fuller, Anthony M

    2015-04-01

    Integrated watershed management based on aquatic ecosystems has been increasingly acknowledged. Such a change in the philosophy of water environment management requires recognizing the carrying capacity of aquatic ecosystems for human society from a more general perspective. The concept of the water ecological carrying capacity is therefore put forward, which considers both water resources and water environment, connects socio-economic development to aquatic ecosystems and provides strong support for integrated watershed management. In this paper, the authors proposed an ESEF-based measure of water ecological carrying capacity and constructed ESEF-based models of water ecological footprint and capacity, aiming to evaluate water ecological carrying capacity with footprint methods. A regional model of Taihu Lake Basin was constructed and applied to evaluate the water ecological carrying capacity in Changzhou City which located in the upper reaches of the basin. Results showed that human demand for water ecosystem services in this city had exceeded the supply capacity of local aquatic ecosystems and the significant gap between demand and supply had jeopardized the sustainability of local aquatic ecosystems. Considering aqua-product provision, water supply and pollutant absorption in an integrated way, the scale of population and economy aquatic ecosystems in Changzhou could bear only 54% of the current status.

  14. ERP and Four Dimensions of Absorptive Capacity: Lessons from a Developing Country

    NASA Astrophysics Data System (ADS)

    Gil, María José Álvarez; Aksoy, Dilan; Kulcsar, Borbala

    Enterprise resource planning systems can grant crucial strategic, operational and information-based benefits to adopting firms when implemented successfully. However, a failed implementation can often result in financial losses rather than profits. Until now, the research on the failures and successes were focused on implementations in large manufacturing and service organizations firms located in western countries, particularly in USA. Nevertheless, IT has gained intense diffusion to developing countries through declining hardware costs and increasing benefits that merits attention as much as developed countries. The aim of this study is to examine the implications of knowledge transfer in a developing country, Turkey, as a paradigm in the knowledge society with a focus on the implementation activities that foster successful installations. We suggest that absorptive capacity is an important characteristic of a firm that explains the success level of such a knowledge transfer.

  15. Causal Relationships among Technology Acquisition, Absorptive Capacity, and Innovation Performance: Evidence from the Pharmaceutical Industry

    PubMed Central

    Jeon, Jieun; Hong, Suckchul; Ohm, Jay; Yang, Taeyong

    2015-01-01

    This paper discusses the importance of absorptive capacity in improving a firm’s innovation performance. Specifically, we examine firm interaction with the knowledge and capabilities of outside organizations and the effect on the firm’s bottom line. We use the impulse-response function of the vector auto-regressive model to gain insight into this relationship by estimating the time required for the effect of each activity level to reach outputs, the spillover effects. We apply this methodology to pharmaceutical firms, which we classify into two sub-groups – large firms and medium and small firms – based on sales. Our results show that the impact of an activity on any other activity is delayed by three years for large firms and by one to two years for small and medium firms. PMID:26181440

  16. The Use of Absorptive Capacity in Improving the New Product Development (NPD

    NASA Astrophysics Data System (ADS)

    Gunawan, W.; Gerardus, P.; Tji, B. J.; Richard, K.

    2017-01-01

    The term Absorptive Capacity (AC) refers to maximizing the external knowledge transfer into the organization in order to improve its performance. Since its introduction in year 1990, AC has been applied widely in many fields such as: economy, business, KM, HR, intellectual capital, IT, operation management, marketing, etc. Due to its wide application, nevertheless, The AC application in both Indonesian industry and higher education institutions (HEIs) are still rare to find. The Indonesian Directorate General of Higher Education (DGHE) has encouraged creating effective collaboration model that enables to link the HEIs with the industries in order to improve knowledge creation in improving product development that can be used by the firms. For this reason, the article examines the effective AC model that enables to assist in improving new product development (NPD) process in the polytechnic perspectives.

  17. Causal Relationships among Technology Acquisition, Absorptive Capacity, and Innovation Performance: Evidence from the Pharmaceutical Industry.

    PubMed

    Jeon, Jieun; Hong, Suckchul; Ohm, Jay; Yang, Taeyong

    2015-01-01

    This paper discusses the importance of absorptive capacity in improving a firm's innovation performance. Specifically, we examine firm interaction with the knowledge and capabilities of outside organizations and the effect on the firm's bottom line. We use the impulse-response function of the vector auto-regressive model to gain insight into this relationship by estimating the time required for the effect of each activity level to reach outputs, the spillover effects. We apply this methodology to pharmaceutical firms, which we classify into two sub-groups--large firms and medium and small firms--based on sales. Our results show that the impact of an activity on any other activity is delayed by three years for large firms and by one to two years for small and medium firms.

  18. Climate Adaptation Capacity for Conventional Drinking Water Treatment Facilities

    NASA Astrophysics Data System (ADS)

    Levine, A.; Goodrich, J.; Yang, J.

    2013-12-01

    Water supplies are vulnerable to a host of climate- and weather-related stressors such as droughts, intense storms/flooding, snowpack depletion, sea level changes, and consequences from fires, landslides, and excessive heat or cold. Surface water resources (lakes, reservoirs, rivers, and streams) are especially susceptible to weather-induced changes in water availability and quality. The risks to groundwater systems may also be significant. Typically, water treatment facilities are designed with an underlying assumption that water quality from a given source is relatively predictable based on historical data. However, increasing evidence of the lack of stationarity is raising questions about the validity of traditional design assumptions, particularly since the service life of many facilities can exceed fifty years. Given that there are over 150,000 public water systems in the US that deliver drinking water to over 300 million people every day, it is important to evaluate the capacity for adapting to the impacts of a changing climate. Climate and weather can induce or amplify changes in physical, chemical, and biological water quality, reaction rates, the extent of water-sediment-air interactions, and also impact the performance of treatment technologies. The specific impacts depend on the watershed characteristics and local hydrological and land-use factors. Water quality responses can be transient, such as erosion-induced increases in sediment and runoff. Longer-term impacts include changes in the frequency and intensity of algal blooms, gradual changes in the nature and concentration of dissolved organic matter, dissolved solids, and modulation of the microbiological community structure, sources and survival of pathogens. In addition, waterborne contaminants associated with municipal, industrial, and agricultural activities can also impact water quality. This presentation evaluates relationships between climate and weather induced water quality variability and

  19. Intestinal absorptive capacity, intestinal permeability and jejunal histology in HIV and their relation to diarrhoea.

    PubMed Central

    Keating, J; Bjarnason, I; Somasundaram, S; Macpherson, A; Francis, N; Price, A B; Sharpstone, D; Smithson, J; Menzies, I S; Gazzard, B G

    1995-01-01

    Intestinal function is poorly defined in patients with HIV infection. Absorptive capacity and intestinal permeability were assessed using 3-O-methyl-D-glucose, D-xylose, L-rhamnose, and lactulose in 88 HIV infected patients and the findings were correlated with the degree of immunosuppression (CD4 counts), diarrhoea, wasting, intestinal pathogen status, and histomorphometric analysis of jejunal biopsy samples. Malabsorption of 3-O-methyl-D-glucose and D-xylose was prevalent in all groups of patients with AIDS but not in asymptomatic, well patients with HIV. Malabsorption correlated significantly (r = 0.34-0.56, p < 0.005) with the degree of immune suppression and with body mass index. Increased intestinal permeability was found in all subgroups of patients. The changes in absorption-permeability were of comparable severity to those found in patients with untreated coeliac disease. Jejunal histology, however, showed only mild changes in the villus height/crypt depth ratio as compared with subtotal villus atrophy in coeliac disease. Malabsorption and increased intestinal permeability are common in AIDS patients. Malabsorption, which has nutritional implications, relates more to immune suppression than jejunal morphological changes. PMID:8549936

  20. Relating water absorption features to soil moisture characteristics

    NASA Astrophysics Data System (ADS)

    Tian, Jia; Philpot, William D.

    2015-09-01

    The spectral reflectance of a sample of quartz sand was monitored as the sample progressed from air-dry to fully saturated, and then back to air-dry. Wetting was accomplished by spraying small amounts of water on the surface of the sample, and collecting spectra whenever change occurred. Drying was passive, driven by evaporation from the sand surface, with spectra collected every 5 minutes until the sample was air dry. Water content was determined by monitoring the weight of the sample through both wetting and drying. There was a pronounced difference in the pattern of change in reflectance during wetting and drying, with the differences being apparent both in spectral details (i.e., the depth of absorption bands) and in the magnitude of the reflectance for a particular water content. The differences are attributable to the disposition of water in the sample. During wetting, water initially occurred only on the surface, primarily as water adsorbed onto sand particles. With increased wetting the water infiltrated deeper into the sample, gradually covering all particles and filling the pore spaces. During drying, water and air were distributed throughout the sample for most of the drying period. The differences in water distribution are assumed to be the cause of the differences in reflectance and to the differences in the depths of four strong water absorption bands.

  1. Absorptive capacity as a guiding concept for effective public sector management and conservation of freshwater ecosystems.

    PubMed

    Murray, K; Roux, D J; Nel, J L; Driver, A; Freimund, W

    2011-05-01

    The ability of an organisation to recognise the value of new external information, acquire it, assimilate it, transform, and exploit it, namely its absorptive capacity (AC), has been much researched in the context of commercial organisations and even applied to national innovation. This paper considers four key AC-related concepts and their relevance to public sector organisations with mandates to manage and conserve freshwater ecosystems for the common good. The concepts are the importance of in-house prior related knowledge, the importance of informal knowledge transfer, the need for motivation and intensity of effort, and the importance of gatekeepers. These concepts are used to synthesise guidance for a way forward in respect of such freshwater management and conservation, using the imminent release of a specific scientific conservation planning and management tool in South Africa as a case study. The tool comprises a comprehensive series of maps that depict national freshwater ecosystem priority areas for South Africa. Insights for implementing agencies relate to maintaining an internal science, rather than research capacity; making unpublished and especially tacit knowledge available through informal knowledge transfer; not underestimating the importance of intensity of effort required to create AC, driven by focussed motivation; and the potential use of a gatekeeper at national level (external to the implementing organisations), possibly playing a more general 'bridging' role, and multiple internal (organisational) gatekeepers playing the more limited role of 'knowledge translators'. The role of AC as a unifying framework is also proposed.

  2. Absorptive Capacity as a Guiding Concept for Effective Public Sector Management and Conservation of Freshwater Ecosystems

    NASA Astrophysics Data System (ADS)

    Murray, K.; Roux, D. J.; Nel, J. L.; Driver, A.; Freimund, W.

    2011-05-01

    The ability of an organisation to recognise the value of new external information, acquire it, assimilate it, transform, and exploit it, namely its absorptive capacity (AC), has been much researched in the context of commercial organisations and even applied to national innovation. This paper considers four key AC-related concepts and their relevance to public sector organisations with mandates to manage and conserve freshwater ecosystems for the common good. The concepts are the importance of in-house prior related knowledge, the importance of informal knowledge transfer, the need for motivation and intensity of effort, and the importance of gatekeepers. These concepts are used to synthesise guidance for a way forward in respect of such freshwater management and conservation, using the imminent release of a specific scientific conservation planning and management tool in South Africa as a case study. The tool comprises a comprehensive series of maps that depict national freshwater ecosystem priority areas for South Africa. Insights for implementing agencies relate to maintaining an internal science, rather than research capacity; making unpublished and especially tacit knowledge available through informal knowledge transfer; not underestimating the importance of intensity of effort required to create AC, driven by focussed motivation; and the potential use of a gatekeeper at national level (external to the implementing organisations), possibly playing a more general `bridging' role, and multiple internal (organisational) gatekeepers playing the more limited role of `knowledge translators'. The role of AC as a unifying framework is also proposed.

  3. 49 CFR 179.201-10 - Water capacity marking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Water capacity marking. 179.201-10 Section 179.201-10 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank...

  4. Modeling sulfur dioxide absorption by fine water spray

    SciTech Connect

    Cheng-Hsiung Huang

    2005-07-01

    A novel theoretical model was developed to determine the removal efficiency of sulfur dioxide using fine water spray. The droplet pH, diameter, S(IV) concentration, sulfur dioxide concentration, and liquid-to-gas ratio are found to influence the absorption of sulfur dioxide by the fine water spray. The results demonstrate that the absorption of sulfur dioxide by the fine water spray increases as the droplet diameter falls. The concentration gradient between the interface of the gaseous and liquid phases causes the absorption of sulfur dioxide by the droplets to increase as the initial S(IV) concentration decreases or the sulfur dioxide concentration increases. The results indicate that the performance of the fine water spray in removing sulfur dioxide is generally improved by reducing the droplet diameter or the initial S(IV) concentration, or by increasing the sulfur dioxide concentration, the droplet pH or the liquid-to-gas ratio. The proposed model reveals the parameters that should be controlled in using a fine water spray device and a method for improving its performance in removing sulfur dioxide.

  5. Absorptivity of water vapor for 10.6 micron radiation

    NASA Technical Reports Server (NTRS)

    Pugh, E. R.; Krech, R. H.

    1982-01-01

    Attention is called to recent measurements of the absorptivity of water vapor to 10.6-micron laser radiation made using shock-heated H2O/H2 and H2O/Ar mixtures and a probe CO2 laser. It is noted that these measurements give values about a factor of 2 lower than Ludwig's (1971) low resolution values. It is also argued that Fowler's (1981) high values are not likely to be caused by excited water molecules. It is shown that very intense laser radiation would be required to obtain any appreciable vibrational nonequilibrium. Within the narrow spectral range of 944-948/cm, no significant variation in absorption coefficient (suitably normalized) is observed as a function of laser line, water vapor concentration, total pressure, or diluent gas.

  6. An environmentally friendly method for the fabrication of reduced graphene oxide foam with a super oil absorption capacity.

    PubMed

    He, Yongqiang; Liu, Yue; Wu, Tao; Ma, Junkui; Wang, Xingrui; Gong, Qiaojuan; Kong, Weina; Xing, Fubao; Liu, Yu; Gao, Jianping

    2013-09-15

    Three kinds of graphene oxide (GO) foams were fabricated using different freezing methods (unidirectional freezing drying (UDF), non-directional freezing drying, and air freezing drying), and the corresponding reduced graphene oxide (RGO) foams were prepared by their thermal reduction of those GO foams. These RGO foams were characterized by Fourier transform infrared spectroscopy, thermal gravimetric analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The absorption process and the factors that influence the absorption capacity were investigated. The RGO foams are hydrophobic and showed extremely high absorbing abilities for organic liquids. The absorption capacity of the RGO foams made by UDF was higher than 100 g g(-1) for all the oils tested (gasoline, diesel oil, pump oil, lubricating oil and olive oil) and had the highest value of about 122 g g(-1) for olive oil. The oil absorption capacity of the GO foams was lower than that of the RGO foams, but for olive oil, the absorption capacity was still high than 70 g g(-1), which is higher than that of most oil absorbents.

  7. Absorption depth profile of water on thermoplastic starch films

    SciTech Connect

    Bonno, B.; Laporte, J.L.; Paris, D.; D'Leon, R.T.

    2000-01-01

    It is well known that petroleum derived polymers are primary environmental contaminants. The study of new packing biodegradable materials has been the object of numerous papers in past years. Some of these new materials are the thermoplastic films derived from wheat starch. In the present paper, the authors study some of properties of wheat starch thermoplastic films, with various amounts of absorbed water, using photoacoustic spectroscopy techniques. The absorption depth profile of water in the starch substrate is determined for samples having a variable water level.

  8. Water vapor absorption in the atmospheric window at 239 GHz

    NASA Technical Reports Server (NTRS)

    Bauer, A.; Godon, M.; Carlier, J.; Ma, Q.

    1995-01-01

    Absolute absorption rates of pure water vapor and mixtures of water vapor and nitrogen have been measured in the atmospheric window at 239 GHz. The dependence on pressure as well as temperature has been obtained. The experimental data are compared with several theoretical or empirical models, and satisfactory agreement is obtained with the models involving a continuum; in the case of pure water vapor, the continuum contribution based upon recent theoretical developments gives good results. The temperature dependence is stronger than that proposed in a commonly used atmospheric transmission model.

  9. A novel procedure to assess the non-enzymatic hydrogen-peroxide antioxidant capacity of metabolites with high UV absorption.

    PubMed

    Csepregi, Kristóf; Hideg, Éva

    2016-12-01

    Assays assessing non-enzymatic hydrogen peroxide antioxidant capacities are often hampered by the high UV absorption of the sample itself. This is a typical problem in studies using plant extracts with high polyphenol content. Our assay is based on comparing the 405 nm absorption of the product of potassium iodine and hydrogen peroxide in the presence and absence of a putative hydrogen peroxide reactive antioxidant. This method is free of interference with either hydrogen peroxide or antioxidant self-absorption and it is also suitable for high-throughput plate reader applications.

  10. Dynamics of absorption properties along a latitudinal gradient: sources of absorption in Australian inland waters

    NASA Astrophysics Data System (ADS)

    Hestir, E. L.; Campbell, G.; Malthus, T. J.; Dekker, A.; Botha, E.

    2013-12-01

    Australian inland waters are optically complex and vary spatially and temporally. Inversion of optical remote sensing data for the retrieval of optically active water quality constituents (chlorophyll, colored dissolved organic matter and total suspended solids) is impeded by the scarcity of inherent optical property (IOP) data sets. In 2012 a major measurement program commenced to improve understanding of IOPs in Australia. Seven large lakes were sampled along a latitudinal gradient in Eastern Australia; in situ observations were made of the absorption properties of the water quality during two epochs (wet and dry season). This study documents the seasonal, inter & intra lake variability of the absorption budget of Australian lakes. These data reveal the sources of biogeochemical constituents determining the light climate of lakes. Optically active water quality constituents (total suspended solids, chlorophyll-a, and colored dissolved organic matter) varied significantly between wet and dry season and between lakes. The primary contribution to the absorption budget was from non-algal particulate matter (NAP; 10-60%), followed by colored dissolved organic matter (CDOM; 20-80%). Absorption from phytoplankton contributed only 0-30% of the total budget. This indicates that these lakes are primarily light limited, though the limitation comes from multiple sources. The contribution of NAP to the total absorption budget showed the greatest amount of variance between wet and dry seasons. Examination of the organic matter and estimated phytoplankton biomass contributions to TSS reveal that chlorophyll is not the primary source of organic matter in Australian lakes: allochthonous inputs are the primary trophic driver. Finally, there is strong regional and seasonal variation in the IOPs of the lakes, with the exception of the slope of CDOM. The slope of CDOM was not significantly different between seasons (p=0.94). Non-parametric stepwise multiple comparisons showed the

  11. [Fog water absorption by the leaves of epiphytes and non - epiphytes in Xishuangbanna].

    PubMed

    Zheng, Yulong; Feng, Yulong

    2006-06-01

    Xishuangbanna is located at the northern margin of tropics. Its climate is different from that of typical tropics, but the rainforest there is not very different from that of the typical tropics in Southeast Asia. The main problems in Xishuangbanna are seasonal drought and low temperature. Fog may contribute to the development of rainforest here, but related studies are few. This study is aimed to know whether the leaves of epiphytes and non - epiphytes in Xishuangbanna can directly absorb fog water and contribute to their water status recovery, and whether epiphytes are more competent than non - epiphytes in their leaf fog water absorption. The study was conducted in dry season, and four species of epiphytes and six species of non - epiphytes were investigated. The effect of fog was imitated by spraying leaves with distilled water. For epiphytes and non - epiphytes, their leaf water potential (phi), relative water content (RWC), and amount of absorbed water increased gradually with the time of spraying, but the phi of epiphytes increased more quickly than that of non - epiphytes. The leaves of epiphytes Bolbitis scandens and Rhaphidophora decursiva could absorb fog water more quickly, and increase their RWC more greatly than those of non - epiphytes, indicating that these epiphytes were more competent than non - epiphytes in their leaf fog water absorption. The fog water absorption capacity of the leaves in epiphytic orchid Coelogyne occultata and Staurochilus dawsonianus was lower than that in Amischotolype hispida and Mananthus patentflora, but higher than that in other four non - epiphytes. The phi of epiphytes at early evening when no fog was formed was significantly lower than that at early morning, suggesting that fog water was absorbed by epiphytes at night to improve their leaf water status. Non - epiphytes did not need to absorb fog water directly through leaves, and they could recover their leaf water status through absorbing soil water by root system

  12. An Exergy Analysis of LiBr-Water Absorption Refrigerators

    NASA Astrophysics Data System (ADS)

    Asano, Hitoshi; Fujii, Terushige; Wang, Xiao; Origane, Takafumi; Katayama, Masatoshi; Inoue, Umeo

    Absorption refrigerators are very efficient as a heat recovery unit in a co-generation system.In order to design an absorption refrigerator for an arbitrary heat source properly, it is important to consider not only quantity but also quality of heat flow. The evaluation of exergy loss in each component is also effective for the improvement of system. This paper deals with the exergy analysis on a LiBr-water absorption refrigerator consisted of a single-and a double-effect cycle driven by the exhaust gas of the micro gas turbine with the output power of about 30 kW. Moreover, exergy loss in absorption process was eva1uated. As a result, it was shown that 80% of the exergy loss in an absorber was caused in absorption process, and the exergy loss decreased with decreasing the change in solution concentration in absorber. In these calculated results,the maximum cooling load of 77.8 kW was obtained from the exhaust gas with the temperature of 2900°C by utilizing both a single-and a double-effect cycles in combination. The energy and exergy efficiency of the system was 88.0% and 25.6%, respectively.

  13. A Novel Absorption Cycle for Combined Water Heating, Dehumidification, and Evaporative Cooling

    SciTech Connect

    CHUGH, Devesh; Gluesenkamp, Kyle R; Abdelaziz, Omar; Moghaddam, Saeed

    2014-01-01

    In this study, development of a novel system for combined water heating, dehumidification, and space evaporative cooling is discussed. Ambient water vapor is used as a working fluid in an open system. First, water vapor is absorbed from an air stream into an absorbent solution. The latent heat of absorption is transferred into the process water that cools the absorber. The solution is then regenerated in the desorber, where it is heated by a heating fluid. The water vapor generated in the desorber is condensed and its heat of phase change is transferred to the process water in the condenser. The condensed water can then be used in an evaporative cooling process to cool the dehumidified air exiting the absorber, or it can be drained if primarily dehumidification is desired. Essentially, this open absorption cycle collects space heat and transfers it to process water. This technology is enabled by a membrane-based absorption/desorption process in which the absorbent is constrained by hydrophobic vapor-permeable membranes. Constraining the absorbent film has enabled fabrication of the absorber and desorber in a plate-and-frame configuration. An air stream can flow against the membrane at high speed without entraining the absorbent, which is a challenge in conventional dehumidifiers. Furthermore, the absorption and desorption rates of an absorbent constrained by a membrane are greatly enhanced. Isfahani and Moghaddam (Int. J. Heat Mass Transfer, 2013) demonstrated absorption rates of up to 0.008 kg/m2s in a membrane-based absorber and Isfahani et al. (Int. J. Multiphase Flow, 2013) have reported a desorption rate of 0.01 kg/m2s in a membrane-based desorber. The membrane-based architecture also enables economical small-scale systems, novel cycle configurations, and high efficiencies. The absorber, solution heat exchanger, and desorber are fabricated on a single metal sheet. In addition to the open arrangement and membrane-based architecture, another novel feature of the

  14. The Role of Cross-Cultural Absorptive Capacity in the Effectiveness of In-Country Cross-Cultural Training

    ERIC Educational Resources Information Center

    Tarique, Ibraiz; Caligiuri, Paula

    2009-01-01

    Based on the theory of absorptive capacity, this study examines the following question. In the context of cross-cultural training, can the amount of previously accumulated cultural knowledge affect the ability of a trainee to absorb further learning about a new culture, thus enhancing total knowledge and presumably cross-cultural adjustment?…

  15. Global terrestrial water storage capacity and flood potential using GRACE

    NASA Astrophysics Data System (ADS)

    Reager, J. T.; Famiglietti, J. S.

    2009-12-01

    Terrestrial water storage anomaly from the Gravity Recovery and Climate Experiment (GRACE) and precipitation observations from the Global Precipitation Climatology Project (GPCP) are applied at the regional scale to show the usefulness of a remotely sensed, storage-based flood potential method. Over the GRACE record length, instances of repeated maxima in water storage anomaly that fall short of variable maxima in cumulative precipitation suggest an effective storage capacity for a given region, beyond which additional precipitation must be met by marked increases in runoff or evaporation. These saturation periods indicate the possible transition to a flood-prone situation. To investigate spatially and temporally variable storage overflow, a monthly storage deficit variable is created and a global map of effective storage capacity is presented for possible use in land surface models. To highlight a flood-potential application, we design a monthly global flood index and compare with Dartmouth Flood Observatory flood maps.

  16. Water in the Earth's Mantle: Mineral-specific IR Absorption Coefficients and Radiative Thermal Conductivities

    NASA Astrophysics Data System (ADS)

    Thomas, S. M.

    2015-12-01

    Minor and trace element chemistry, phase relations, rheology, thermal structure and the role of volatiles and their abundance in the deep Earth mantle are still far from fully explored, but fundamental to understanding the processes involved in Earth formation and evolution. Theory and high pressure experiments imply a significant water storage capacity of nominally anhydrous minerals, such as majoritic garnet, olivine, wadsleyite and ringwoodite, composing the Earth's upper mantle and transition zone to a depth of 660 km. Studying the effect of water incorporation on chemical and physical mineral properties is of importance, because the presence of trace amounts of water, incorporated as OH through charge-coupled chemical substitutions into such nominally anhydrous high-pressure silicates, notably influences phase relations, melting behavior, conductivity, elasticity, viscosity and rheology. Knowledge of absolute water contents in nominally anhydrous minerals is essential for modeling the Earth's interior water cycle. One of the most common and sensitive tools for water quantification is IR spectroscopy for which mineral-specific absorption coefficients are required. Such calibration constants can be derived from hydrogen concentrations determined by independent techniques, such as secondary ion mass spectrometry, Raman spectroscopy or proton-proton(pp)-scattering. Here, analytical advances and mineral-specific IR absorption coefficients for the quantification of H2O in major phases of the Earth's mantle will be discussed. Furthermore, new data from optical absorption measurements in resistively heated diamond-anvil cells at high pressures and temperatures up to 1000 K will be presented. Experiments were performed on synthetic single-crystals of olivine, ringwoodite, majoritic garnet, and Al-bearing phase D with varying iron, aluminum and OH contents to calculate radiative thermal conductivities and study their contribution to heat transfer in the Earth's interior

  17. Theoretical Calculation and Validation of the Water Vapor Continuum Absorption

    NASA Technical Reports Server (NTRS)

    Ma, Qiancheng; Tipping, Richard H.

    1998-01-01

    The primary objective of this investigation is the development of an improved parameterization of the water vapor continuum absorption through the refinement and validation of our existing theoretical formalism. The chief advantage of our approach is the self-consistent, first principles, basis of the formalism which allows us to predict the frequency, temperature and pressure dependence of the continuum absorption as well as provide insights into the physical mechanisms responsible for the continuum absorption. Moreover, our approach is such that the calculated continuum absorption can be easily incorporated into satellite retrieval algorithms and climate models. Accurate determination of the water vapor continuum is essential for the next generation of retrieval algorithms which propose to use the combined constraints of multispectral measurements such as those under development for EOS data analysis (e.g., retrieval algorithms based on MODIS and AIRS measurements); current Pathfinder activities which seek to use the combined constraints of infrared and microwave (e.g., HIRS and MSU) measurements to improve temperature and water profile retrievals, and field campaigns which seek to reconcile spectrally-resolved and broad-band measurements such as those obtained as part of FIRE. Current widely used continuum treatments have been shown to produce spectrally dependent errors, with the magnitude of the error dependent on temperature and abundance which produces errors with a seasonal and latitude dependence. Translated into flux, current water vapor continuum parameterizations produce flux errors of order 10 W/sq m, which compared to the 4 W/sq m magnitude of the greenhouse gas forcing and the 1-2 W/sq m estimated aerosol forcing is certainly climatologically significant and unacceptably large. While it is possible to tune the empirical formalisms, the paucity of laboratory measurements, especially at temperatures of interest for atmospheric applications, preclude

  18. Theoretical Calculation and Validation of the Water Vapor Continuum Absorption

    NASA Technical Reports Server (NTRS)

    Ma, Qiancheng; Tipping, Richard H.

    1998-01-01

    The primary objective of this investigation is the development of an improved parameterization of the water vapor continuum absorption through the refinement and validation of our existing theoretical formalism. The chief advantage of our approach is the self-consistent, first principles, basis of the formalism which allows us to predict the frequency, temperature and pressure dependence of the continuum absorption as well as provide insights into the physical mechanisms responsible for the continuum absorption. Moreover, our approach is such that the calculated continuum absorption can be easily incorporated into satellite retrieval algorithms and climate models. Accurate determination of the water vapor continuum is essential for the next generation of retrieval algorithms which propose to use the combined constraints of multi-spectral measurements such as those under development for EOS data analysis (e.g., retrieval algorithms based on MODIS and AIRS measurements); current Pathfinder activities which seek to use the combined constraints of infrared and microwave (e.g., HIRS and MSU) measurements to improve temperature and water profile retrievals, and field campaigns which seek to reconcile spectrally-resolved and broad-band measurements such as those obtained as part of FIRE. Current widely used continuum treatments have been shown to produce spectrally dependent errors, with the magnitude of the error dependent on temperature and abundance which produces errors with a seasonal and latitude dependence. Translated into flux, current water vapor continuum parameterizations produce flux errors of order 10 W/ml, which compared to the 4 W/m' magnitude of the greenhouse gas forcing and the 1-2 W/m' estimated aerosol forcing is certainly climatologically significant and unacceptably large. While it is possible to tune the empirical formalisms, the paucity of laboratory measurements, especially at temperatures of interest for atmospheric applications, preclude tuning

  19. 30 CFR 75.1107-7 - Water spray devices; capacity; water supply; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... toxic compounds. The quantity of liquid chemicals required shall be proportionately less than water as... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Water spray devices; capacity; water supply..., DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...

  20. 30 CFR 75.1107-7 - Water spray devices; capacity; water supply; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... toxic compounds. The quantity of liquid chemicals required shall be proportionately less than water as... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Water spray devices; capacity; water supply..., DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...

  1. 30 CFR 75.1107-7 - Water spray devices; capacity; water supply; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... toxic compounds. The quantity of liquid chemicals required shall be proportionately less than water as... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Water spray devices; capacity; water supply..., DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...

  2. The role of education and training in absorptive capacity of international technology transfer in the aerospace sector

    NASA Astrophysics Data System (ADS)

    van der Heiden, Patrick; Pohl, Christine; Bin Mansor, Shuhaimi; van Genderen, John

    2015-07-01

    The role of education and training in the aerospace sector for establishing sufficient levels of absorptive capacity in newly industrialized countries is substantial and forms a fundamental part of a nation's ability to establish and cultivate absorptive capacity on a national or organization-specific level. Successful international technology transfer as well as absorption of aerospace technology and knowledge into recipient organizations, depends prodigiously on the types of policy adopted in education and training of all groups and individuals specifically outlined in this paper. The conducted literature review revealed surprisingly few papers that translate these vital issues from theoretical scrutiny into representations that have practical policy value. Through exploration of the seven key aspects of education and training, this paper provides a practical template for policy-makers and practitioners in Asian newly industrialized countries, which may be utilized as a prototype to coordinate relevant policy aspects of education and training in international technology transfer projects across a wide variety of actors and stakeholders in the aerospace realm. A pragmatic approach through tailored practical training for the identified groups and individuals identified in this paper may lead to an enhanced ability to establish and strengthen absorptive capacity in newly industrialized countries through the development of appropriate policy guidelines. The actual coordination between education and training efforts deserves increased research and subsequent translation into policies with practical content in the aerospace sector.

  3. Water Constraints in an Electric Sector Capacity Expansion Model

    SciTech Connect

    Macknick, Jordan; Cohen, Stuart; Newmark, Robin; Martinez, Andrew; Sullivan, Patrick; Tidwell, Vince

    2015-07-17

    This analysis provides a description of the first U.S. national electricity capacity expansion model to incorporate water resource availability and costs as a constraint for the future development of the electricity sector. The Regional Energy Deployment System (ReEDS) model was modified to incorporate water resource availability constraints and costs in each of its 134 Balancing Area (BA) regions along with differences in costs and efficiencies of cooling systems. Water resource availability and cost data are from recently completed research at Sandia National Laboratories (Tidwell et al. 2013b). Scenarios analyzed include a business-as-usual 3 This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. scenario without water constraints as well as four scenarios that include water constraints and allow for different cooling systems and types of water resources to be utilized. This analysis provides insight into where water resource constraints could affect the choice, configuration, or location of new electricity technologies.

  4. Water absorption and transport in bis-silane films.

    PubMed

    Wang, Yimin; Wang, Peng; Kohls, Doug; Hamilton, William A; Schaefer, Dale W

    2009-01-07

    Water (D2O) ingress in bis-amino silane and bis-sulfur silane films was studied by in situ neutron reflectivity. Bis-amino silane film absorbs substantially more D2O (33 vol%) than the bis-sulfur silane film (4.6 vol%) at equilibrium. The volume increase (swelling) of both films, however, is much smaller than the total volume of D2O absorbed in the films. The results suggest that the absorbed water exists in two populations: one is dissolved in the polymer matrix (Henry's mode) while the other occupies unrelaxed free volume existing in the polymer (Langmuir mode). The dominance of Langmuir mode accounts for the small film thickness change during the water absorption. Dual-mode sorption is also consistent with the observed two-stage swelling process whereby an initial rapid increase in film thickness is followed by a slower process extending over 11 h.

  5. Water vapor-nitrogen absorption at CO2 laser frequencies

    NASA Technical Reports Server (NTRS)

    Peterson, J. C.; Thomas, M. E.; Nordstrom, R. J.; Damon, E. K.; Long, R. K.

    1979-01-01

    The paper reports the results of a series of pressure-broadened water vapor absorption measurements at 27 CO2 laser frequencies between 935 and 1082 kaysers. Both multiple traversal cell and optoacoustic (spectrophone) techniques were utilized together with an electronically stabilized CW CO2 laser. Comparison of the results obtained by these two methods shows remarkable agreement, indicating a precision which has not been previously achieved in pressure-broadened studies of water vapor. The data of 10.59 microns substantiate the existence of the large (greater than 200) self-broadening coefficients determined in an earlier study by McCoy. In this work, the case of water vapor in N2 at a total pressure of 1 atm has been treated.

  6. The water absorption effect on the hardness of composites polyester

    NASA Astrophysics Data System (ADS)

    Mohammed, A. A.; Issa, T. T.

    2016-04-01

    Unsaturated polyester resin (UPE) was used as the matrix .The iron woven wire and E-glass fiber type (0 - 9°), were used as a reinforcements additives of weight percentage (5, 10, 15) respectively. Samples were prepared by the hand lay-up method for (UPE), (UPE -Fe) and (UPE- Glass). Chemical analysis was used to identify the composition of Fe wire. Water immersing at room temperature for all samples were done at (2, 5, 7, 9, 12) days. Hardness test (Brinell) showed decreasing with increasing in immersion time for (UPE) from (67) HB to (95) HP after adding the reinforcement Fe fibers, with increasing in the water absorbed content especially in the days (2, 5). The water content of absorption was found to be either decreasing or increasing depending on the number of reinforcing layers added.

  7. Pore-size dependent THz absorption of nano-confined water.

    PubMed

    Sun, Chi-Kuang; You, Borwen; Huang, Yu-Ru; Liu, Kao-Hsiang; Sato, Shusaku; Irisawa, Akiyoshi; Imamura, Motoki; Mou, Chung-Yuan

    2015-06-15

    We performed a THz absorption spectroscopy study on liquid water confined in mesoporous silica materials, MCM-41-S-18 and MCM-41-S-21, of two different pore sizes at room temperatures. We found that stronger confinement with a smaller pore size causes reduced THz absorption, indicating reduced water mobility due to confinement. Combined with recent theoretical studies showing that the microscopic structure of water inside the nanopores can be separated into a core water region and an interfacial water region, our spectroscopy analysis further reveals a bulk-water-like THz absorption behavior in the core water region and a solid-like THz absorption behavior in the interfacial water region.

  8. Human skin binding and absorption of contaminants from ground and surface water during swimming and bathing

    SciTech Connect

    Wester, R.C.; Maibach, H.I. )

    1989-10-01

    Contaminants exist in ground and surface water. Human skin has the capacity to bind and then absorb these contaminants into the body during swimming and bathing. Powdered human stratum corneum will bind both lipid-soluble (alachlor, polychlorinated biphenyls (PCBs), benzene) and water-soluble (nitroaniline) chemicals. In vitro (Human skin) and in vivo (Rhesus monkey) studies show that these chemicals readily distribute into skin, and then some of the chemical is absorbed into the body. Linearity in binding and absorption exists for nitroaniline over a 10-fold concentration range. Multiple exposure to benzene is at least cumulative. Binding and adsorption can be significant for exposures as short as 30 minutes, and will increase with time. Adsorption with water dilution increased for alachlor, but not for dinoseb. Soap reversed the partitioning of alachlor between human stratum corneum and water. The PCBs could be removed from skin by soap and water for up to 3 hours and the decontamination potential decreased, due to continuing skin absorption. The model that in vitro and in vivo systems used should permit easy estimation of this area of extensive human exposure effect on risk assessment. 5 refs., 9 tabs.

  9. An innovative method for water resources carrying capacity research--Metabolic theory of regional water resources.

    PubMed

    Ren, Chongfeng; Guo, Ping; Li, Mo; Li, Ruihuan

    2016-02-01

    The shortage and uneven spatial and temporal distribution of water resources has seriously restricted the sustainable development of regional society and economy. In this study, a metabolic theory for regional water resources was proposed by introducing the biological metabolism concept into the carrying capacity of regional water resources. In the organic metabolic process of water resources, the socio-economic system consumes water resources, while products, services and pollutants, etc. are output. Furthermore, an evaluation index system which takes into the characteristics of the regional water resources, the socio-economic system and the sustainable development principle was established based on the proposed theory. The theory was then applied to a case study to prove its availability. Further, suggestions aiming at improving the regional water carrying capacity were given on the basis of a comprehensive analysis of the current water resources situation.

  10. A Water Vapor Differential Absorption LIDAR Design for Unpiloted Aerial Vehicles

    NASA Technical Reports Server (NTRS)

    DeYoung, Russell J.; Mead, Patricia F.

    2004-01-01

    This system study proposes the deployment of a water vapor Differential Absorption LIDAR (DIAL) system on an Altair unmanned aerial vehicle (UAV) platform. The Altair offers improved payload weight and volume performance, and longer total flight time as compared to other commercial UAV's. This study has generated a preliminary design for an Altair based water vapor DIAL system. The design includes a proposed DIAL schematic, a review of mechanical challenges such as temperature and humidity stresses on UAV deployed DIAL systems, an assessment of the available capacity for additional instrumentation (based on the proposed design), and an overview of possible weight and volume improvements associated with the use of customized electronic and computer hardware, and through the integration of advanced fiber-optic and laser products. The results of the study show that less than 17% of the available weight, less than 19% of the volume capacity, and approximately 11% of the electrical capacity is utilized by the proposed water vapor DIAL system on the Altair UAV.

  11. Technical, Managerial and Financial (TMF) Capacity Resources for Small Drinking Water Systems

    EPA Pesticide Factsheets

    Resources are available to help public water systems build the technical, managerial and financial (TMF) capacity. TMF capacity is necessary to achieve and maintain long-term sustainability and compliance with national safe drinking water regulations.

  12. Water absorption and moisture permeation properties of chitosan/poly(acrylamide-co-itaconic acid) IPC films.

    PubMed

    Bajpai, M; Bajpai, S K; Jyotishi, Pooja

    2016-03-01

    In this work, aqueous solutions of chitosan (Ch) and [poly(acrylamide(AAm)-co-itaconicacid(IA)] have been mixed to yield Ch/poly(AAm-co-IA) Inter-polyelectrolyte complex (IPC) films. The films were characterized by FTIR, X-ray diffraction (XRD) and thermo gravimetric analysis (TGA). There was remarkable increase in the crystalline nature of IPC films. The films were investigated for their water absorption capacity in the physiological fluid (PF) of pH 7.4 at 37 °C. The amount of IA present in the film forming solutions affected the water absorption behavior of the resulting films. The dynamic water uptake data were interpreted by various kinetic models. The effect of pH on the swelling ratio (SR) indicated that the films showed highest swelling in lower as well as higher pH media. The water vapor transmission rates (WVTR) were obtained in the range of 6000-6645 g/m(2)/day.

  13. Detection of water vapour absorption around 363nm in measured atmospheric absorption spectra and its effect on DOAS evaluations

    NASA Astrophysics Data System (ADS)

    Lampel, Johannes; Polyansky, Oleg. L.; Kyuberis, Alexandra A.; Zobov, Nikolai F.; Tennyson, Jonathan; Lodi, Lorenzo; Pöhler, Denis; Frieß, Udo; Platt, Ulrich; Beirle, Steffen; Wagner, Thomas

    2016-04-01

    Water vapour is known to absorb light from the microwave region to the blue part of the visible spectrum at a decreasing magnitude. Ab-initio approaches to model individual absorption lines of the gaseous water molecule predict absorption lines until its dissociation limit at 243 nm. We present first evidence of water vapour absorption at 363 nm from field measurements based on the POKAZATEL absorption line list by Polyansky et al. (2016) using data from Multi-Axis differential optical absorption spectroscopy (MAX-DOAS) and Longpath (LP)-DOAS measurements. The predicted absorptions contribute significantly to the observed optical depths with up to 2 × 10-3. Their magnitude correlates well (R2 = 0.89) to simultaneously measured well-established water vapour absorptions in the blue spectral range from 452-499 nm, but is underestimated by a factor of 2.6 ± 0.6 in the ab-initio model. At a spectral resolution of 0.5nm this leads to a maximum absorption cross-section value of 5.4 × 10-27 cm2/molec at 362.3nm. The results are independent of the employed cross-section data to compensate for the overlayed absorption of the oxygen dimer O4. The newly found absorption can have a significant impact on the spectral retrieval of absorbing trace-gas species in the spectral range around 363 nm. Its effect on the spectral analysis of O4, HONO and OClO are discussed.

  14. 30 CFR 75.1107-7 - Water spray devices; capacity; water supply; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Water spray devices; capacity; water supply; minimum requirements. 75.1107-7 Section 75.1107-7 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Fire Protection Fire Suppression Devices...

  15. Water absorption in a refractive index model for bacterial spores

    NASA Astrophysics Data System (ADS)

    Siegrist, K. M.; Thrush, E.; Airola, M.; Carr, A. K.; Limsui, D. M.; Boggs, N. T.; Thomas, M. E.; Carter, C. C.

    2009-05-01

    The complexity of biological agents can make it difficult to identify the important factors impacting scattering characteristics among variables such as size, shape, internal structure and biochemical composition, particle aggregation, and sample additives. This difficulty is exacerbated by the environmentally interactive nature of biological organisms. In particular, bacterial spores equilibrate with environmental humidity by absorption/desorption of water which can affect both the complex refractive index and the size/shape distributions of particles - two factors upon which scattering characteristics depend critically. Therefore accurate analysis of experimental data for determination of refractive index must take account of particle water content. First, spectral transmission measurements to determine visible refractive index done on suspensions of bacterial spores must account for water (or other solvent) uptake. Second, realistic calculations of aerosol scattering cross sections should consider effects of atmospheric humidity on particle water content, size and shape. In this work we demonstrate a method for determining refractive index of bacterial spores bacillus atropheus (BG), bacillus thuringiensis (BT) and bacillus anthracis Sterne (BAs) which accounts for these effects. Visible index is found from transmission measurements on aqueous and DMSO suspensions of particles, using an anomalous diffraction approximation. A simplified version of the anomalous diffraction theory is used to eliminate the need for knowledge of particle size. Results using this approach indicate the technique can be useful in determining the visible refractive index of particles when size and shape distributions are not well known but fall within the region of validity of anomalous dispersion theory.

  16. Contact sponge water absorption test implemented for in situ measures

    NASA Astrophysics Data System (ADS)

    Gaggero, Laura; Scrivano, Simona

    2016-04-01

    The contact sponge method is a non-destructive in-situ methodology used to estimate a water uptake coefficient. The procedure, unlike other in-situ measurement was proven to be directly comparable to the water uptake laboratory measurements, and was registered as UNI 11432:2011. The UNI Normal procedure requires to use a sponge with known density, soaked in water, weighed, placed on the material for 1 minute (UNI 11432, 2011; Pardini & Tiano, 2004), then weighed again. Difficulties arise in operating on test samples or on materials with porosity varied for decay. While carrying on the test, fluctuations in the bearing of the environmental parameters were negligible, but not the pressure applied to the surface, that induced the release of different water amounts towards the material. For this reason we designed a metal piece of the same diameter of the plate carrying the sponge, to be screwed at the tip of a pocket penetrometer. With this instrument the sponge was kept in contact with the surface for 1 minute applying two different loads, at first pushed with 0.3 kg/cm2 in order to press the sponge, but not its holder, against the surface. Then, a load of 1.1 kg/ cm2 was applied, still avoiding deviating the load to the sponge holder. We applied both the current and our implemented method to determine the water absorption by contact sponge on 5 fresh rock types (4 limestones: Fine - and Coarse grained Pietra di Vicenza, Rosso Verona, Breccia Aurora, and the silicoclastic Macigno sandstone). The results show that 1) the current methodology imply manual skill and experience to produce a coherent set of data; the variable involved are in fact not only the imposed pressure but also the compression mechanics. 2) The control on the applied pressure allowed reproducible measurements. Moreover, 3) the use of a thicker sponge enabled to apply the method even on rougher surfaces, as the device holding the sponge is not in contact with the tested object. Finally, 4) the

  17. Mechanical- and oil-durable superhydrophobic polyester materials for selective oil absorption and oil/water separation.

    PubMed

    Wu, Lei; Zhang, Junping; Li, Bucheng; Wang, Aiqin

    2014-01-01

    The low stability and complicated fabrication procedures seriously hindered practical applications of superhydrophobic materials. Here we present a facile approach for preparing durable superhydrophobic polyester materials by dip-coating in a nanocomposite solution of polymerized tetraethoxysilane and n-hexadecyltriethoxysilane. The coated samples exhibit excellent superhydrophobicity, superoleophilicity, mechanical and chemical stabilities. This is attributed to the tight binding of the nanocomposite on the polyester fibers and the inherent stability of silicone. The coated samples can quickly absorb petrol, diesel and crude oil, and show very high selectivity in oil/water separation. In addition, the coated samples could maintain their superhydrophobicity, oil absorption capacity and oil/water selectivity after harsh mechanical damage, 90 days of immersion in oils and ten cycles of absorption-desorption. Moreover, this approach is simple and can be easily scaled up for producing samples on a large size, which makes it very promising for practical oil absorption.

  18. Public water supplies of North Carolina : a summary of water sources, use, treatment, and capacity of water-supply systems

    USGS Publications Warehouse

    Mann, L.T.

    1978-01-01

    Data were collected during 1970-76 on 224 public water supply systems in North Carolina with 500 or more customers. This report summarizes these data that were previously published in five separate regional reports. The data are presented in order to Council of Government region, county, and water system name and include population served, average and maximum daily use, industrial use, water source, allowable draft of surface-water supplies, raw water pumping capacity, raw and finished water storage, type of water treatment, treatment plant capacity, and a summary of the chemical quality of finished water. Tables and maps provide cross references for system names, counties, Council of Government regions and water source.

  19. Social Networks, Social Media and Absorptive Capacity in Regional Small and Medium Enterprises (SMES) in Australia

    ERIC Educational Resources Information Center

    Bosua, Rachelle; Evans, Nina; Sawyer, Janet

    2013-01-01

    Small and Medium Enterprises (SMEs) are major sources of prosperity and employment and are viewed as critical to regional development in Australia. A key factor to foster productivity and growth in SMEs is their ability to identify, acquire, transform and exploit external knowledge. This ability, referred to as the "absorptive capacity…

  20. Enhancement of the grafting performance and of the water absorption of cassava starch graft copolymer by gamma radiation

    NASA Astrophysics Data System (ADS)

    Kiatkamjornwong, Suda; Meechai, Nispa

    1997-06-01

    Enhancement of the gamma radiation grafting of acrylonitrile onto gelatinized cassava starch was investigated. Infrared spectrometry was used to follow the chemical changes in the grafting reaction and from saponification. The saponified starch- g-PAN (HSPAN) was then characterized in terms of grafting parameters to provide a guide for the optimum total dose (kGy) and the appropriate ratio of starch/acrylonitrile for a fixed dose rate of 2.5 × 10 -1 kGy/min. Other dose rates were also carried out to obtain the appropriate result of grafting copolymerization and of water absorption. A thin aluminium foil, covering the inner wall of the reaction vessel, was found to be far more effective than any other metal films in the enhancement of the grafting reaction and the water absorption as well. Nitric acid in the medium increases the grafting yield and the water absorption. Methyl ether hydroquinone inhibitor was evaluated for its ability to increase homopolymerization and decrease graft reaction. When styrene was used as a comonomer, it hampered the grafting of acrylonitrile onto starch backbone. The water absorption capacity was improved by freeze-drying the HSPAN. The treatment of the HSPAN with aluminium trichloride hexahydrate was found to enhance the degree of wicking, but to decrease the water absorbency.

  1. Gamma radiation induces hydrogen absorption by copper in water

    PubMed Central

    Lousada, Cláudio M.; Soroka, Inna L.; Yagodzinskyy, Yuriy; Tarakina, Nadezda V.; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A.; Jonsson, Mats

    2016-01-01

    One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories. PMID:27086752

  2. Micropulse water vapor differential absorption lidar: transmitter design and performance.

    PubMed

    Nehrir, Amin R; Repasky, Kevin S; Carlsten, John L

    2012-10-22

    An all diode-laser-based micropulse differential absorption lidar (DIAL) laser transmitter for tropospheric water vapor and aerosol profiling is presented. The micropulse DIAL (MPD) transmitter utilizes two continuous wave (cw) external cavity diode lasers (ECDL) to seed an actively pulsed, overdriven tapered semiconductor optical amplifier (TSOA). The MPD laser produces up to 7 watts of peak power over a 1 µs pulse duration (7 µJ) and a 10 kHz pulse repetition frequency. Spectral switching between the online and offline seed lasers is achieved on a 1Hz basis using a fiber optic switch to allow for more accurate sampling of the atmospheric volume between the online and offline laser shots. The high laser spectral purity of greater than 0.9996 coupled with the broad tunability of the laser transmitter will allow for accurate measurements of tropospheric water vapor in a wide range of geographic locations under varying atmospheric conditions. This paper describes the design and performance characteristics of a third generation MPD laser transmitter with enhanced laser performance over the previous generation DIAL system.

  3. Gamma radiation induces hydrogen absorption by copper in water.

    PubMed

    Lousada, Cláudio M; Soroka, Inna L; Yagodzinskyy, Yuriy; Tarakina, Nadezda V; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A; Jonsson, Mats

    2016-04-18

    One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.

  4. Gamma radiation induces hydrogen absorption by copper in water

    NASA Astrophysics Data System (ADS)

    Lousada, Cláudio M.; Soroka, Inna L.; Yagodzinskyy, Yuriy; Tarakina, Nadezda V.; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A.; Jonsson, Mats

    2016-04-01

    One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.

  5. The Impacts of Different Expansion Modes on Performance of Small Solar Energy Firms: Perspectives of Absorptive Capacity

    PubMed Central

    Chen, Hsing Hung; Shen, Tao; Xu, Xin-long; Ma, Chao

    2013-01-01

    The characteristics of firm's expansion by differentiated products and diversified products are quite different. However, the study employing absorptive capacity to examine the impacts of different modes of expansion on performance of small solar energy firms has never been discussed before. Then, a conceptual model to analyze the tension between strategies and corporate performance is proposed to filling the vacancy. After practical investigation, the results show that stronger organizational institutions help small solar energy firms expanded by differentiated products increase consistency between strategies and corporate performance; oppositely, stronger working attitudes with weak management controls help small solar energy firms expanded by diversified products reduce variance between strategies and corporate performance. PMID:24453837

  6. Sensitivity of the global water cycle to the water-holding capacity of land

    SciTech Connect

    Milly, P.C.D.; Dunne, K.A. )

    1994-04-01

    The sensitivity of the global water cycle to the water-holding capacity of the plant-root zone of continental soils is estimated by simulations using a mathematical model of the general circulation of the atmosphere, with prescribed ocean surface temperatures and prescribed cloud. With an increase of the globally constant storage capacity, evaporation from the continents rises and runoff falls, because a high storage capacity enhances the ability of the soil to store water from periods of excess for later evaporation during periods of shortage. In addition, atmospheric feedbacks associated with higher precipitation and lower potential evaporation drive further changes in evaporation and runoff. Most changes in evaporation and runoff occur in the tropics and the northern middle-latitude rain belts. Global evaporation from land increases by 7 cm for each doubling of storage capacity. Sensitivity is negligible for capacity above 60 cm. In the tropics and in the extratropics,increased continental evaporation is split between increased continental precipitation and decreased convergence of atmospheric water vapor from ocean to land. In the tropics, this partitioning is strongly affected by induced circulation changes, which are themselves forced by changes in latent heating. In the northern middle and high latitudes, the increased continental evaporation moistens the atmosphere. This change in humidity of the atmosphere is greater above the continents than above the oceans, and the resulting reduction in the sea-land humidity gradient causes a decreased onshore transport of water vapor by transient eddies. Results here may have implications for problems in global hydrology and climate dynamics, including effects of water resource development on global precipitation, climatic control of plant rooting characteristics, climatic effects of tropical deforestation, and climate-model errors. 21 refs., 13 figs., 21 tabs.

  7. Amount of leachant and water absorption levels of wood treated with borates and water repellents.

    PubMed

    Baysal, Ergun; Sonmez, Abdullah; Colak, Mehmet; Toker, Hilmi

    2006-12-01

    Wood protection efficacy of borates against biological agents, flame retardancy, and suitability to the environment is well known. Since borates can be applied to timber as water based solutions, they are preferred economically as well. Even though they are highly mobile in wood, boron compounds are widely used in timber preservation. Borates migrate in liquid and increase the hygroscopicity of wood in damp conditions. This study deals with the physical restriction of water access in wood by impregnating water repellent agents into wood to limit amount of leachant and water absorption levels of wood after boron treatment. Borates were incorporated with polyethylene glycol-400 (PEG-400) their bulking effect in wood was considered. Results indicated that the amount of leachates from wood treated with borates in PEG-400 was remarkably higher compared to those of wood treated with the aqueous solutions of borates. Water absorption (WA) levels of wood treated with aqueous solutions of borates were higher than those of their treated samples with the solutions in PEG-400. Secondary treatments of wood with the water repellent (WR) chemicals following borate impregnation reduced the leaching of chemicals from wood in water and also WA of the specimens were less than those of the wood treated with only borates from aqueous and PEG solutions. Styrene (St) was the most effective monomer among the other agents used in terms of immobility effect on borates and WA.

  8. Fabrication of Functional Polyurethane/Rare Earth Nanocomposite Membranes by Electrospinning and Its VOCs Absorption Capacity from Air

    PubMed Central

    Ge, Jun Cong; Choi, Nag Jung

    2017-01-01

    Volatile organic compounds (VOCs) are a source of air pollution and are harmful to both human health and the environment. In this study, we fabricated polyurethane/rare earth (PU/RE) composite nanofibrous membranes via electrospinning with the aim of removing VOCs from air. The morphological structure of PU/RE nanofibrous mats was investigated using field emission scanning electron microscopy (FE-SEM), fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) experimental analyses. A certain amount of RE (up to 50 wt. % compared to PU pellets) nanoparticles (NPs) could be loaded on/into PU fibers. The tensile strength of PU/RE nanofibrous membranes decreased slightly with the increasing RE powder content. The PU nanofiber containing 50 wt. % RE powder had the smallest fiber diameter of 356 nm; it also showed the highest VOC absorption capacity compared with other composite membranes, having an absorption capacity about three times greater than pure PU nanofibers. In addition, all of the PU/RE nanofibrous membranes readily absorbed styrene the most, followed by xylene, toluene, benzene and chloroform. Therefore, the PU/RE nanofibrous membrane can play an important role in removing VOCs from the air, and its development prospects are impressive because they are emerging materials. PMID:28336894

  9. In-situ X-ray absorption spectroscopy analysis of capacity fade in nanoscale-LiCoO2

    NASA Astrophysics Data System (ADS)

    Patridge, Christopher J.; Love, Corey T.; Swider-Lyons, Karen E.; Twigg, Mark E.; Ramaker, David E.

    2013-07-01

    The local structure of nanoscale (∼10-40 nm) LiCoO2 is monitored during electrochemical cycling utilizing in-situ X-ray absorption spectroscopy (XAS). The high surface area of the LiCoO2 nanoparticles not only enhances capacity fade, but also provides a large signal from the particle surface relative to the bulk. Changes in the nanoscale LiCoO2 metal-oxide bond lengths, structural disorder, and chemical state are tracked during cycling by adapting the delta mu (Δμ) technique in complement with comprehensive extended X-ray absorption fine structure (EXAFS) modeling. For the first time, we use a Δμ EXAFS method, and by comparison of the difference EXAFS spectra, extrapolate significant coordination changes and reduction of cobalt species with cycling. This combined approach suggests Li-Co site exchange at the surface of the nanoscale LiCoO2 as a likely factor in the capacity fade and irreversible losses in practical, microscale LiCoO2.

  10. In-situ X-ray absorption spectroscopy analysis of capacity fade in nanoscale-LiCoO{sub 2}

    SciTech Connect

    Patridge, Christopher J.; Swider-Lyons, Karen E.; Twigg, Mark E.; Ramaker, David E.

    2013-07-15

    The local structure of nanoscale (∼10–40 nm) LiCoO{sub 2} is monitored during electrochemical cycling utilizing in-situ X-ray absorption spectroscopy (XAS). The high surface area of the LiCoO{sub 2} nanoparticles not only enhances capacity fade, but also provides a large signal from the particle surface relative to the bulk. Changes in the nanoscale LiCoO{sub 2} metal-oxide bond lengths, structural disorder, and chemical state are tracked during cycling by adapting the delta mu (Δμ) technique in complement with comprehensive extended X-ray absorption fine structure (EXAFS) modeling. For the first time, we use a Δμ EXAFS method, and by comparison of the difference EXAFS spectra, extrapolate significant coordination changes and reduction of cobalt species with cycling. This combined approach suggests Li–Co site exchange at the surface of the nanoscale LiCoO{sub 2} as a likely factor in the capacity fade and irreversible losses in practical, microscale LiCoO{sub 2}. - Graphical abstract: Electrochemical cycling of Li-ion batteries has strong impact on the structure and integrity of the cathode active material particularly near the surface/electrolyte interface. In developing a new method, we have used in-situ X-ray absorption spectroscopy during electrochemical cycling of nanoscale LiCoO{sub 2} to track changes during charge and discharge and between subsequent cycles. Using difference spectra, several small changes in Co-O bond length, Co-O and Co-Co coordination, and site exchange between Co and Li sites can be tracked. These methods show promise as a new technique to better understand processes which lead to capacity fade and loss in Li-ion batteries. - Highlights: • A new method is developed to understand capacity fade in Li-ion battery cathodes. • Structural changes are tracked during Li intercalation/deintercalation of LiCoO{sub 2}. • Surface structural changes are emphasized using nanoscale-LiCoO{sub 2} and difference spectra. • Full multiple

  11. Absorption coefficients for water vapor at 193 nm from 300 to 1073 K

    NASA Technical Reports Server (NTRS)

    Kessler, W. J.; Carleton, K. L.; Marinelli, W. J.

    1993-01-01

    Measurements of the water absorption coefficient at 193 nm from 300 to 1073 K are reported. The measurements were made using broadband VUV radiation and a monochromator-based detection system. The water vapor was generated by a saturator and metered into a flowing, 99 cm absorption cell via a water vapor mass flow meter. The 193 nm absorption coefficient measurements are compared to room temperature and high temperature shock tube measurements with good agreement. The absorption can be parameterized by a nu3 vibrational mode reaction coordinate and the thermal population of the nu3 mode.

  12. [Water storage capacity of qinghai spruce (Picea crassifolia) forest canopy in Qilian Mountains].

    PubMed

    Peng, Huan-hua; Zhao, Chuan-yan; Xu, Zhong-lin; Peng, Shou-zhang; Wang, Yao

    2011-09-01

    By the methods of direct measurement and regression analysis, this paper estimated the water storage capacity of Picea crassifolia forest canopy in Guantan in Qilianshan Mountains, based on the observed throughfall and the laboratory experimental data about the water storage capacity of various canopy components in 2008. Due to the impacts of various factors, differences existed in the canopy water storage capacity estimated by the two methods. The regression analysis was mainly impacted by the measurement approaches of the throughfall, the maximum water storage capacity estimated being 0.69 mm, whereas the direct measurement was mainly impacted by tree height, diameter at breast height, plant density, and leaf area index, with the estimated maximum water storage capacity being 0.77 mm. The direct measurement showed that the maximum water storage capacity per unit area of the canopy components of the forest was in the order of barks (0.31 mm) > branches (0.28 mm) > leaves (0.08 mm).

  13. Approaches to a Quantitative Analytical Description of Low Frequency Sound Absorption in Sea Water,

    DTIC Science & Technology

    1980-09-01

    Liebermann (1948) found that the absorption coefficient, a, was frequency dependent in the range 100- 1000 kHz and could be attributed to perturbations due...Affecting the Attenuation of Low Frequency Sound in Sea Water", MRL Report No. R-782 (1979). 2. Liebermann , R.M., "Origin of Sound Absorption in Water

  14. Iron analysis in atmospheric water samples by atomic absorption spectroscopy (AAS) in water-methanol.

    PubMed

    Sofikitis, A M; Colin, J L; Desboeufs, K V; Losno, R

    2004-01-01

    To distinguish between Fe(II) and Fe(III) species in atmospheric water samples, we have adapted an analytical procedure based on the formation of a specific complex between Fe(II) and ferrozine (FZ) on a chromatographic column. After elution of Fe(III), the Fe(II) complex is recovered with water-methanol (4:1). The possibility of trace iron measurements in this complex medium by graphite-furnace atomic-absorption spectrometry has been investigated. A simplex optimization routine was required to complete the development of the analytical method.

  15. Temperature Dependences of Mechanisms Responsible for the Water-Vapor Continuum Absorption

    NASA Technical Reports Server (NTRS)

    Ma, Qiancheng

    2014-01-01

    The water-vapor continuum absorption plays an important role in the radiative balance in the Earth's atmosphere. It has been experimentally shown that for ambient atmospheric conditions, the continuum absorption scales quadratically with the H2O number density and has a strong, negative temperature dependence (T dependence). Over the years, there have been three different theoretical mechanisms postulated: far-wings of allowed transition lines, water dimers, and collision-induced absorption. The first mechanism proposed was the accumulation of absorptions from the far-wings of the strong allowed transition lines. Later, absorption by water dimers was proposed, and this mechanism provides a qualitative explanation for the continuum characters mentioned above. Despite the improvements in experimental data, at present there is no consensus on which mechanism is primarily responsible for the continuum absorption.

  16. The effect of canola meal tannins on the intestinal absorption capacity of broilers using a D-xylose test.

    PubMed

    Mansoori, B; Rogiewicz, A; Slominski, B A

    2015-12-01

    In three D-xylose absorption experiments, the effect of 1% HCl/methanol, 70% methanol or 70% acetone extracts of canola meal (CM) or 70% acetone extract of soybean meal (SBM) containing polyphenols, phenolic acids, tannins and phytic acid on intestinal absorption capacity of broilers was determined. In Exp. 1, the experimental groups received orally D-xylose solution alone or with methanol/HCl, methanol or acetone extracts of CM. In Exp. 2, the experimental groups received D-xylose alone or with acetone extracts of CM or SBM. In Exp. 3, the experimental groups received D-xylose plus sucrose solution or D-xylose plus acetone extracts of CM or SBM. In Exps. 2 and 3, the CM extracts contained 2.7 and 2.6, 2.4 and 2.3, 3.2 and 3.2, and 2.4 and 2.2 times higher polyphenols, phenolic acids, tannins and condensed tannins than the corresponding SBM extracts respectively. Blood samples were collected in 40-min intervals, and plasma D-xylose was measured. Compared to the Control, plasma D-xylose in Exp. 1 was lower (p < 0.001) by 81, 69 and 73% at 40-min, by 41, 44 and 37% at 80-min and by 22, 31, and 23% at 120-min post-ingestion of the HCl/methanol, methanol and acetone extracts respectively. In both Exps. 2 and 3, plasma D-xylose level was lower (p < 0.001) in groups dosed with CM extract or SBM extract at each time of blood collection, when compared to the respective Control group. However, in Exp. 3, birds dosed with SBM extract had higher plasma D-xylose than CM extract-dosed birds by 28, 8 and 21% at 40, 80 and 120 min respectively (p < 0.01). In conclusion, although CM extract caused a lower absorption of D-xylose, based on 5 to 10% of CM inclusion levels in practical broiler rations, the soluble bioactive components of CM will likely have minor impact on the absorption capacity of the chicken intestine.

  17. From drought to deluge: how information overload saturated absorption capacity in a disrupted health sector.

    PubMed

    Beesley, Mark; Cometto, Giorgio; Pavignani, Enrico

    2011-11-01

    Provision of technical assistance is a common form of support to health sectors emerging from prolonged conflicts. But what actions signal that the Ministry of Health (MoH) is, or is not, actively analysing and digesting the output of this assistance? Where are the boundaries between doing with and doing for? This article presents a qualitative description of an early post-conflict policy process in southern Sudan, which represented an opportunity to test these boundaries. The methodology of provision of technical assistance to the MoH in the formulation of a human resource plan is reviewed. Initial objectives are compared with the results accomplished. Shortcomings are discussed and recommendations for technical assistance programmes in similar contexts are provided. Between October 2005 and May 2006, World Health Organization advisers supported the MoH in conducting a human resources assessment to lay the grounds for a human resources development plan. The study employed three consultants, ten data collectors and entailed questionnaires, field visits, interviews and a review of literature. The survey shed new important evidence on the human resources situation in southern Sudan, both in quantitative and qualitative terms, and formulated specific recommendations. The formulation of the human resources plan, however, took another direction, apparently unrelated to the findings of the survey. Various factors contributed to the scope and methodology of the survey being inappropriate to the reality of southern Sudan. In the presence of systemic capacity gaps, including uncertain governance and precarious management systems, the benefit of one-off comprehensive surveys is likely to be negligible. Inaction is not always rooted in the lack of information, as too often assumed; this case study exposes the limits of a rationalistic approach to policy formulation and planning in the field of human resources for health. An alternative approach that entails incremental steps

  18. Phase behavior of TXs/toluene/water microemulsion systems for solubilization absorption of toluene.

    PubMed

    Liu, Lian; Tian, Senlin; Ning, Ping

    2010-01-01

    Triton Xs (TXs) surfactants/cosurfactant/water/oil (toluene) microemulsion systems for enhancing toluene solubilization were proposed and its potential was investigated for toluene removal from gas stream. The results indicated that TX-100 was superior to other TXs surfactants in removing toluene without cosurfactant. The efficiency of cosurfactants for improving toluene solubilization capacity follows the order: amine > alcohol > acid. According to the factor analysis, the linear cosurfactants are better than the branched ones. The effects of hydrophile-lipophile balance (HLB), salt (NaCl) concentration and temperature on the formation of microemulsion system were also discussed. The results suggested that the optimum value of HLB was 15, the effect of NaCl concentration on the system was inconspicuous and the lower temperature enhanced the solubilization capacity. Nonionic surfactant-based microemulsions had a significant absorption enhancement for toluene, indicated by as much as 82.72% of toluene in phase composition diagram, which will have a great prospect in air pollution treatment.

  19. Investigations of the 1 KHZ Sound Absorption in Sea Water.

    DTIC Science & Technology

    1983-01-15

    Experimental Methods 18 I. Introduction 18 2. Spherical Resonator 21 a. Principles of Operation 21 b. Preparation of Samples and the Resonator 24 c... Experimental Procedure 28 3. Temperature jump 34 a. Principles of Operation 34 b. Preparation of Samples 39 c. Measurements and Analysis 40 IV... Experimental Results 42 1. Low Frequency Sound Absorption and Relaxation 42 Frequency Data a. Background 42 b. Resonator Sound Absorption Data 44 c. Accuracy of

  20. Hydrogen capacity and absorption rate of the SAES St707 non-evaporable getter at various temperatures.

    SciTech Connect

    Hsu, Irving; Mills, Bernice E.

    2010-08-01

    A prototype of a tritium thermoelectric generator (TTG) is currently being developed at Sandia. In the TTG, a vacuum jacket reduces the amount of heat lost from the high temperature source via convection. However, outgassing presents challenges to maintaining a vacuum for many years. Getters are chemically active substances that scavenge residual gases in a vacuum system. In order to maintain the vacuum jacket at approximately 1.0 x 10{sup -4} torr for decades, nonevaporable getters that can operate from -55 C to 60 C are going to be used. This paper focuses on the hydrogen capacity and absorption rate of the St707{trademark} non-evaporable getter by SAES. Using a getter testing manifold, we have carried out experiments to test these characteristics of the getter over the temperature range of -77 C to 60 C. The results from this study can be used to size the getter appropriately.

  1. Transparent hydrogel with enhanced water retention capacity by introducing highly hydratable salt

    NASA Astrophysics Data System (ADS)

    Bai, Yuanyuan; Chen, Baohong; Xiang, Feng; Zhou, Jinxiong; Wang, Hong; Suo, Zhigang

    2014-10-01

    Polyacrylamide hydrogels containing salt as electrolyte have been used as highly stretchable transparent electrodes in flexible electronics, but those hydrogels are easy to dry out due to water evaporation. Targeted, we try to enhance water retention capacity of polyacrylamide hydrogel by introducing highly hydratable salts into the hydrogel. These hydrogels show enhanced water retention capacity in different level. Specially, polyacrylamide hydrogel containing high content of lithium chloride can retain over 70% of its initial water even in environment with relative humidity of only 10% RH. The excellent water retention capacities of these hydrogels will make more applications of hydrogels become possible.

  2. Transparent hydrogel with enhanced water retention capacity by introducing highly hydratable salt

    SciTech Connect

    Bai, Yuanyuan; Xiang, Feng; Wang, Hong E-mail: suo@seas.harvard.edu; Chen, Baohong; Zhou, Jinxiong; Suo, Zhigang E-mail: suo@seas.harvard.edu

    2014-10-13

    Polyacrylamide hydrogels containing salt as electrolyte have been used as highly stretchable transparent electrodes in flexible electronics, but those hydrogels are easy to dry out due to water evaporation. Targeted, we try to enhance water retention capacity of polyacrylamide hydrogel by introducing highly hydratable salts into the hydrogel. These hydrogels show enhanced water retention capacity in different level. Specially, polyacrylamide hydrogel containing high content of lithium chloride can retain over 70% of its initial water even in environment with relative humidity of only 10% RH. The excellent water retention capacities of these hydrogels will make more applications of hydrogels become possible.

  3. Towards quantitative atmospheric water vapor profiling with differential absorption lidar.

    PubMed

    Dinovitser, Alex; Gunn, Lachlan J; Abbott, Derek

    2015-08-24

    Differential Absorption Lidar (DIAL) is a powerful laser-based technique for trace gas profiling of the atmosphere. However, this technique is still under active development requiring precise and accurate wavelength stabilization, as well as accurate spectroscopic parameters of the specific resonance line and the effective absorption cross-section of the system. In this paper we describe a novel master laser system that extends our previous work for robust stabilization to virtually any number of multiple side-line laser wavelengths for the future probing to greater altitudes. In this paper, we also highlight the significance of laser spectral purity on DIAL accuracy, and illustrate a simple re-arrangement of a system for measuring effective absorption cross-section. We present a calibration technique where the laser light is guided to an absorption cell with 33 m path length, and a quantitative number density measurement is then used to obtain the effective absorption cross-section. The same absorption cell is then used for on-line laser stabilization, while microwave beat-frequencies are used to stabilize any number of off-line lasers. We present preliminary results using ∼300 nJ, 1 μs pulses at 3 kHz, with the seed laser operating as a nanojoule transmitter at 822.922 nm, and a receiver consisting of a photomultiplier tube (PMT) coupled to a 356 mm mirror.

  4. 21 CFR 130.12 - General methods for water capacity and fill of containers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false General methods for water capacity and fill of containers. 130.12 Section 130.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FOOD STANDARDS: GENERAL General Provisions § 130.12 General methods for water capacity and...

  5. Poultry water holding capacity measurements using infrared spectroscopies correlated to traditional methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water holding capacity (WHC) in chicken meat is directly correlated with the quality of the meat. Lower water holding capacity is linked with decreased sensory qualities and therefore lower consumer satisfaction. Additionally, measurement of WHC is subject to wide variations which can depend on many...

  6. The influence of water mixtures on the dermal absorption of glycol ethers

    SciTech Connect

    Traynor, Matthew J.; Wilkinson, Simon C.; Williams, Faith M. . E-mail: F.M.Williams@ncl.ac.uk

    2007-01-15

    Glycol ethers are solvents widely used alone and as mixtures in industrial and household products. Some glycol ethers have been shown to have a range of toxic effects in humans following absorption and metabolism to their aldehyde and acid metabolites. This study assessed the influence of water mixtures on the dermal absorption of butoxyethanol and ethoxyethanol in vitro through human skin. Butoxyethanol penetrated human skin up to sixfold more rapidly from aqueous solution (50%, 450 mg/ml) than from the neat solvent. Similarly penetration of ethoxyethanol was increased threefold in the presence of water (50%, 697 mg/ml). There was a corresponding increase in apparent permeability coefficient as the glycol ether concentration in water decreased. The maximum penetration rate of water also increased in the presence of both glycol ethers. Absorption through a synthetic membrane obeyed Fick's Law and absorption through rat skin showed a similar profile to human skin but with a lesser effect. The mechanisms for this phenomenon involves disruption of the stratum corneum lipid bilayer by desiccation by neat glycol ether micelles, hydration with water mixtures and the physicochemical properties of the glycol ether-water mixtures. Full elucidation of the profile of absorption of glycol ethers from mixtures is required for risk assessment of dermal exposure. This work supports the view that risk assessments for dermal contact scenarios should ideally be based on absorption data obtained for the relevant formulation or mixture and exposure scenario and that absorption derived from permeability coefficients may be inappropriate for water-miscible solvents.

  7. A parameterization for the absorption of solar radiation by water vapor in the earth's atmosphere

    NASA Technical Reports Server (NTRS)

    Wang, W.-C.

    1976-01-01

    A parameterization for the absorption of solar radiation as a function of the amount of water vapor in the earth's atmosphere is obtained. Absorption computations are based on the Goody band model and the near-infrared absorption band data of Ludwig et al. A two-parameter Curtis-Godson approximation is used to treat the inhomogeneous atmosphere. Heating rates based on a frequently used one-parameter pressure-scaling approximation are also discussed and compared with the present parameterization.

  8. Strong enhancement in light absorption by black carbon due to aerosol water uptake

    NASA Astrophysics Data System (ADS)

    Fierce, Laura; Mena, Francisco; Riemer, Nicole; Bond, Tami C.; Bauer, Susanne E.

    2015-04-01

    Black carbon exerts a strong, yet highly uncertain, warming effect on the climate. One source of uncertainty in predicting black carbon's radiative effects is the absorption per black carbon mass. Although models suggest that light absorption is strongly enhanced if black carbon is coated with non-absorbing aerosol material, recent ambient observations find only weak absorption enhancement from aerosol coatings. In this study, we use a particle-resolved aerosol model to evaluate how oversimplified representations of particle composition impact modeled light absorption by black carbon. We show that oversimplifying the representation of particle composition leads to overestimation of modeled absorption enhancement. In order to improve global model representations of BC absorption, we performed a nonparametric regression on particle-reolved model data from a series of simulations. Through this nonparametric analysis we derived a relationship for absorption enhancement as a function of variables that global models already track, the population-averaged composition and the environmental relative humidity. Finally, we show how this nonparametric relationship can be exploited for use in global models to improve predictions of absorption by black carbon. In order to quantify the global-scale impact of water uptake on light absorption by black carbon, we applied the relationship for absorption enhancement to output of the climate model GISS-MATRIX. We find weak absorption enhancement in locations with low relative humidity, but light absorption is strongly enhanced in humid regions. This enhancement in light absorption by particles taking up water strongly impacts black carbon's radiative effects at the global scale, enhancing light absorption by black carbon by 20% relative to dry conditions.

  9. Water absorption and desorption in shuttle ablator and insulation materials

    NASA Technical Reports Server (NTRS)

    Whitaker, A. F.; Smith, C. F.; Wooden, V. A.; Cothren, B. E.; Gregory, H.

    1982-01-01

    Shuttle systems ablator and insulation materials underwent water soak with subsequent water desorption in vacuum. Water accumulation in these materials after a soak for 24 hours ranged from +1.1% for orbiter tile to +161% for solid rocket booster MSA-1. After 1 minute in vacuum, water retention ranged from none in the orbiter tile to +70% for solid rocket booster cork.

  10. Temperature dependences of mechanisms responsible for the water-vapor continuum absorption. II. Dimers and collision-induced absorption.

    PubMed

    Leforestier, C; Tipping, R H; Ma, Q

    2010-04-28

    We investigated the magnitude and temperature dependence (T dependence) of the dimer absorption in the region of 0-600 cm(-1) and the collision-induced absorption (CIA) in the region of 0-1150 cm(-1). Together with our previous study of the self water-vapor continuum contributions resulting from far-wing line shapes of the allowed H(2)O lines in the infrared window between 800 and 1150 cm(-1), we find that the three mechanisms have completely different T dependence behaviors. The dimer absorption has the strongest negative T dependence and the continuum absorption from far wings of the allowed lines has a moderately strong negative one. Meanwhile, the CIA exhibits a mild T dependence. In addition, their T dependence patterns are quite different. The T dependence of the far-wing theory varies significantly as the frequency of interest omega varies. For CIA, in general, its T dependence is mildly negative, but becomes slightly positive in the window region between the H(2)O bands. In contrast, the T dependence of the dimer absorption varies slightly as omega varies. In the microwave and submillimeter region, its T dependence becomes uniform. Concerning the relative importance for each of these three mechanisms, we find that in the infrared widow, the far-wing contributions are the dominant source of the self-continuum. Within the band, its contributions are definitely responsible for the measured continuum data. But, it is impossible to draw quantitatively conclusions on its relative importance unless one is able to improve the accuracy of the local line calculations significantly. On the other hand, within the pure rotational band, the dimer absorptions are a minor contributor to the self-continuum measurements, and its role becomes more important in the microwave and submillimeter regions. Finally, based on our study we conclude that contributions to the self-continuum from CIA in the frequency region of 0-1150 cm(-1) are negligible.

  11. EVALUATING CAPACITIES OF GAC PRELOADED WITH NATURAL WATER

    EPA Science Inventory

    Adsorption studies are conducted to determine how preloading a natural groundwater onto GAC affects the adsorption of cis-1,2-dichloroexthene in small-scale and pilot-scale columns. Capacities are determined from batch-isotherm tests, microcolumns, and pilot columns, which are p...

  12. Dataset used to improve liquid water absorption models in the microwave

    DOE Data Explorer

    Turner, David

    2015-12-14

    Two datasets, one a compilation of laboratory data and one a compilation from three field sites, are provided here. These datasets provide measurements of the real and imaginary refractive indices and absorption as a function of cloud temperature. These datasets were used in the development of the new liquid water absorption model that was published in Turner et al. 2015.

  13. Atmospheric Water Vapour Differential Absorption Measurements with an Infrared Sounder.

    DTIC Science & Technology

    1982-03-01

    such as amonia . As the differential absorption was only of the order of 2 dB for the above measurements (at 450 m range), the measurements were repeated...frequent(ref.7), and most seriously affect surface based radio frequency sensors and communications systems. Further development and refinement of the

  14. [Water environmental capacity calculation model for the rivers in drinking water source conservation area].

    PubMed

    Chen, Ding-jiang; Lü, Jun; Shen, Ye-na; Jin, Shu-quan; Shi, Yi-ming

    2008-09-01

    Based on the one-dimension model for water environmental capacity (WEC) in river, a new model for the WEC estimation in river-reservoir system was developed in drinking water source conservation area (DWSCA). In the new model, the concept was introduced that the water quality target of the rivers in DWSCA was determined by the water quality demand of reservoir for drinking water source. It implied that the WEC of the reservoir could be used as the water quality control target at the reach-end of the upstream rivers in DWSCA so that the problems for WEC estimation might be avoided that the differences of the standards for a water quality control target between in river and in reservoir, such as the criterions differences for total phosphorus (TP)/total nitrogen (TN) between in reservoir and in river according to the National Surface Water Quality Standard of China (GB 3838-2002), and the difference of designed hydrology conditions for WEC estimation between in reservoir and in river. The new model described the quantitative relationship between the WEC of drinking water source and of the river, and it factually expressed the continuity and interplay of these low water areas. As a case study, WEC for the rivers in DWSCA of Laohutan reservoir located in southeast China was estimated using the new model. Results indicated that the WEC for TN and TP was 65.05 t x a(-1) and 5.05 t x a(-1) in the rivers of the DWSCA, respectively. According to the WEC of Laohutan reservoir and current TN and TP quantity that entered into the rivers, about 33.86 t x a(-1) of current TN quantity should be reduced in the DWSCA, while there was 2.23 t x a(-1) of residual WEC of TP in the rivers. The modeling method was also widely applicable for the continuous water bodies with different water quality targets, especially for the situation of higher water quality control target in downstream water body than that in upstream.

  15. Water absorption characteristics and structural properties of rice for sake brewing.

    PubMed

    Mizuma, Tomochika; Kiyokawa, Yoshifumi; Wakai, Yoshinori

    2008-09-01

    This study investigated the water absorption curve characteristics and structural properties of rice used for sake brewing. The parameter values in the water absorption rate equation were calculated using experimental data. Differences between sample parameters for rice used for sake brewing and typical rice were confirmed. The water absorption curve for rice suitable for sake brewing showed a quantitatively sharper turn in the S-shaped water absorption curve than that of typical rice. Structural characteristics, including specific volume, grain density, and powdered density of polished rice, were measured by a liquid substitution method using a Gay-Lussac pycnometer. In addition, we calculated internal porosity from whole grain and powdered grain densities. These results showed that a decrease in internal porosity resulted from invasion of water into the rice grain, and that a decrease in the grain density affected expansion during the water absorption process. A characteristic S-shape water absorption curve for rice suitable for sake brewing was related to the existence of an invisible Shinpaku-like structure.

  16. EPA Method 245.1: Determination of Mercury in Water by Cold Vapor Atomic Absorption Spectrometry

    EPA Pesticide Factsheets

    SAM lists this method for preparation and analysis of aqueous liquid and drinking water samples. This method will determine mercuric chloride and methoxyethylmercuric acetate as total mercury using cold vapor atomic absorption spectrometry.

  17. Optoacoustic measurements of water vapor absorption at selected CO laser wavelengths in the 5-micron region

    NASA Technical Reports Server (NTRS)

    Menzies, R. T.; Shumate, M. S.

    1976-01-01

    Measurements of water vapor absorption were taken with a resonant optoacoustical detector (cylindrical pyrex detector, two BaF2 windows fitted into end plates at slight tilt to suppress Fabry-Perot resonances), for lack of confidence in existing spectral tabular data for the 5-7 micron region, as line shapes in the wing regions of water vapor lines are difficult to characterize. The measurements are required for air pollution studies using a CO laser, to find the differential absorption at the wavelengths in question due to atmospheric constituents other than water vapor. The design and performance of the optoacoustical detector are presented. Effects of absorption by ambient NO are considered, and the fixed-frequency discretely tunable CO laser is found suitable for monitoring urban NO concentrations in a fairly dry climate, using the water vapor absorption data obtained in the study.

  18. Ultraviolet (250-550  nm) absorption spectrum of pure water.

    PubMed

    Mason, John D; Cone, Michael T; Fry, Edward S

    2016-09-01

    Data for the spectral light absorption of pure water from 250 to 550 nm have been obtained using an integrating cavity made from a newly developed diffuse reflector with a very high UV reflectivity. The data provide the first scattering-independent measurements of absorption coefficients in the spectral gap between well-established literature values for the absorption coefficients in the visible (>400  nm) and UV (<200  nm). A minimum in the absorption coefficient has been observed in the UV at 344 nm; the value is 0.000811±0.000227  m-1.

  19. Derivation of water vapour absorption cross-sections in the red region

    NASA Technical Reports Server (NTRS)

    Lal, M.; Chakrabarty, D. K.

    1994-01-01

    Absorption spectrum in 436 to 448 nm wavelength region gives NO2 and O3 column densities. This spectrum can also give H2O column density. The spectrum in the range of 655 to 667 nm contains absorption due to NO3 and H2O. Combining the absorption spectra in the wavelength ranges of 436 to 448 and 655 to 667 nm, water vapor absorption cross-sections in this range comes out to be of the order of 2.0 x 10(exp -24) cm(exp -2).

  20. Evaluating Beijing's human carrying capacity from the perspective of water resource constraints.

    PubMed

    Zhang, Yingxuan; Chen, Min; Zhou, Wenhua; Zhuang, Changwei; Ouyang, Zhiyun

    2010-01-01

    As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city's future development. We developed a method to quantify the carrying capacity of Beijing's water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45:22:33 (% of total, respectively), an optimized structure as 40:20:40, and an ideal structure as 50:15:35. We also considered four domestic water quotas: 55, 75, 95, and 115 m3/(person x yr). The urban carrying capacity of 10-12 million was closest to Beijing's actual 2003 population for all three water-use structures with urban domestic water use of 75 m3/(person x yr). However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5-6 million. Thus, Beijing's population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing's excessive population and propose measures to mitigate these problems.

  1. IR Absorption Coefficients for the Quantification of Water in Hydrous Ringwoodite

    NASA Astrophysics Data System (ADS)

    Thomas, S.; Jacobsen, S. D.; Bina, C. R.; Smyth, J. R.; Frost, D. J.

    2009-12-01

    Raman spectroscopy, combined with the ‘Comparator technique’ has been developed to determine water contents ranging from a few wt ppm to wt% in glasses and nominally anhydrous minerals including garnets, olivine, and SiO2 polymorphs (Thomas et al. 2009). The routine is one promising example of quantification tools to determine mineral specific molar absorption coefficients (ɛ) for IR spectroscopy. Mineral specific absorption coefficients are required because general IR calibrations do not necessarily apply to minerals with water incorporated as hydroxyl point defects. Here we utilize the ‘Comparator technique’ to provide ɛ-values for a set of synthetic Fe-free and Fe-bearing (Fo90) ringwoodites, as well as for γ-Mg2GeO4. Ringwoodite is considered one of the major phases of the Earth’s lower transition zone (520-660 km depth) and the knowledge of its absolute water storage capacity is essential for modeling the Earth’s deep water cycle. Samples were synthesized at variable P-T conditions in a multi-anvil press and cover a range of OH contents. Single-crystals were characterized using X-ray diffraction and IR spectroscopy. Mineral specific IR absorption coefficients were calculated from independently determined water contents from Raman spectroscopy. Unpolarized IR spectra of Mg-ringwoodite show broad absorption features in the OH region with band maxima at ~2350, 2538, 3127, 3172, 3598 and 3688 cm-1. In the spectra of Fe-bearing ringwoodite and γ-Mg2GeO4 the maxima of the main OH band are shifted to 3172 cm-1 and 3207 cm-1, respectively. For Mg-ringwoodite with the mean wavenumber (area-weighted average of the peak position) of 3109 cm-1 an ɛ-value of 170000 ± 51000 L cm-2 / molH2O was determined. For a Fo90 sample with the mean wavenumber of 3132 cm-1 the value was calculated to be 123000 ± 37000 L cm-2 / molH2O. The latter two values are in good agreement with the data from the linear calibration of ~159000 L cm-2 / molH2O and ~153000 L cm-2

  2. Static Characteristics of Absorption Chiller-Heater Supplying Cold and Hot Water Simultaneously

    NASA Astrophysics Data System (ADS)

    Inoue, Naoyuki; Irie, Tomoyoshi

    Absorption chiller-heaters which can supply both chilled water and hot water at the same time, are used for cooling and heating air conditioning systems. In this paper, we classified absorption cold and hot water generating cycles and control methods, studied these absorption cycles by cycle simulation. In economizer cycle, condensed refrigerant which heats hot water is transported to cooling cycle and used effectively for cooling chilled water, Concerning with transported condensed refrigerant, there are two methods, all condensed refrigerant or required refrigerant for cooling are transported to cooling cycle, and required refrigerant method is better for energy saving. Adding improvement of solution control to this economizer cycle, simultaneous cold and hot water supplying chiller-heaters have good characteristics of energy saving in the all region.

  3. Absorption of Sunlight by Water Vapor in Cloudy Conditions: A Partial Explanation for the Cloud Absorption Anomaly

    NASA Technical Reports Server (NTRS)

    Crisp, D.

    1997-01-01

    The atmospheric radiative transfer algorithms used in most global general circulation models underestimate the globally-averaged solar energy absorbed by cloudy atmospheres by up to 25 W/sq m. The origin of this anomalous absorption is not yet known, but it has been attributed to a variety of sources including oversimplified or missing physical processes in these models, uncertainties in the input data, and even measurement errors. Here, a sophisticated atmospheric radiative transfer model was used to provide a more comprehensive description of the physical processes that contribute to the absorption of solar radiation by the Earth's atmosphere. We found that the amount of sunlight absorbed by a cloudy atmosphere is inversely proportional to the solar zenith angle and the cloud top height, and directly proportional to the cloud optical depth and the water vapor concentration within the clouds. Atmospheres with saturated, optically-thick, low clouds absorbed about 12 W/sq m more than clear atmospheres. This accounts for about 1/2 to 1/3 of the anomalous ab- sorption. Atmospheres with optically thick middle and high clouds usually absorb less than clear atmospheres. Because water vapor is concentrated within and below the cloud tops, this absorber is most effective at small solar zenith angles. An additional absorber that is distributed at or above the cloud tops is needed to produce the amplitude and zenith angle dependence of the observed anomalous absorption.

  4. STORM WATER BEST MANAGEMENT PRACTICES: CAPACITIES, CAPABILITIES, AND SOME LIMITATIONS

    EPA Science Inventory

    This presentation will cover the basics of what a storm water best management practices and focus on infiltration-type practices using the example of rain gardens. I will demonstrate how water moves through rain gardens with a simple hydrologic model and discuss ancillary benefit...

  5. Study of Water Absorption Lines in the Near Infrared

    DTIC Science & Technology

    1975-02-17

    the absorption coefficient is better approximated by the sum of Matcha -N«. oec short range contribution and W-BB dispersion contribution. The...and W. Byers Brown, Molecular Physics 2S, 1105 (1973). 5. R. L. Matcha and R. K. Nesbet, Phys. Rev. 1_6_0, 72 (1967). I H. B. Levine, Phys. Rev...reasurcrents of Ouren, ^eltqen Gaide, Helbing and Pauly. The dipole moment function is taken from ab initio 9 calculations of Matcha and Nesbet. With

  6. Spallation occurrence from polyamide materials irradiated by thermal plasma with water absorption

    NASA Astrophysics Data System (ADS)

    Nakano, Tomoyuki; Tanaka, Yasunori; Nakagawa, T.; Shinsei, N.; Uesugi, Y.; Ishijima, T.

    2016-09-01

    This paper first describes the effect of water absorption in polyamide material irradiated by thermal plasmas on the occurrence of spallation phenomena. The interaction between polyamide materials and arc plasmas occurs particularly in the low voltage circuit breaker and aerospace fields. Spallation phenomena are those in which polymer particles are ejected from polymer bulk materials irradiated by high heat flux. To confirm the effect of water absorption into the polyamide material on spallation phenomena, polyamide specimens with and without water absorption were irradiated by Ar inductively coupled thermal plasma. The results show that the polyamide specimen with water absorption ejected spallation particles, whereas the polyamide specimen without water absorption were only slightly ejected, indicating that water absorption promotes the occurrence of spallation. The cooling effects of the spallation polyamide 66 (PA66) particles ablation were also estimated in hot air to assess the arc quenching ability from the spallation particle inclusion. This estimation showed that 10 and more PA66 particles inclusion might decrease the air temperature by 3000 K effectively, which can be useful to enhance arc quenching in circuit breakers working in air.

  7. Effect of Water Vapor Absorption on Measurements of Atmospheric Nitrate Radical by LP-DOAS

    NASA Astrophysics Data System (ADS)

    Li, Su-wen; Liu, Wen-qing; Xie, Pin-hua; Yang, Yi-jun; Chen, De-bao; Li, Zheng

    2008-10-01

    During the measurement of atmospheric nitrate radical by long-path differential optical absorption spec-troscopy, water vapor strong absorption could affect the measurement of nitrate radical and detection limits of system. Under the tropospheric condition, the optical density of water vapor absorption is non-linearly dependent on column density. An effective method was developed to eliminate the effect of water vapor absorption. Reference spectra of water vapor based on the daytime atmospheric absorption spectra, when fitted together with change of cross section with water vapor column densities, gave a more accurate fitting of water vapor absorptions, thus its effect on the measurements of nitrate radical could be restricted to a minimum and detection limits of system reached 3.6 ppt. The modified method was applied during an intensive field campaign in the Pearl River Delta, China. The NO3 concentration in polluted air masses varied from 3.6 ppt to 82.5 ppt with an average level of 23.6±1.8 ppt.

  8. Transporters involved in glucose and water absorption in the Dysdercus peruvianus (Hemiptera: Pyrrhocoridae) anterior midgut.

    PubMed

    Bifano, Thaís D; Alegria, Thiago G P; Terra, Walter R

    2010-09-01

    Little is known about insect intestinal sugar absorption, in spite of the recent findings, and even less has been published regarding water absorption. The aim of this study was to shed light on putative transporters of water and glucose in the insect midgut. Glucose and water absorptions by the anterior ventriculus of Dysdercus peruvianus midgut were determined by feeding the insects with a glucose and a non-absorbable dye solution, followed by periodical dissection of insects and analysis of ventricular contents. Glucose absorption decreases glucose/dye ratios and water absorption increases dye concentrations. Water and glucose transports are activated (water 50%, glucose 33%) by 50 mM K(2)SO(4) and are inhibited (water 46%, glucose 82%) by 0.2 mM phloretin, the inhibitor of the facilitative hexose transporter (GLUT) or are inhibited (water 45%, glucose 35%) by 0.1 mM phlorizin, the inhibitor of the Na(+)-glucose cotransporter (SGLT). The results also showed that the putative SGLT transports about two times more water relative to glucose than the putative GLUT. These results mean that D. peruvianus uses a GLUT-like transporter and an SGLT-like transporter (with K(+) instead of Na(+)) to absorb dietary glucose and water. A cDNA library from D. peruvianus midgut was screened and we found one sequence homologous to GLUT1, named DpGLUT, and another to a sodium/solute symporter, named DpSGLT. Semi-quantitative RT-PCR studies revealed that DpGLUT and DpSGLTs mRNA were expressed in the anterior midgut, where glucose and water are absorbed, but not in fat body, salivary gland and Malpighian tubules. This is the first report showing the involvement of putative GLUT and SGLT in both water and glucose midgut absorption in insects.

  9. Water absorption by secondary organic aerosol and its effect on inorganic aerosol behavior

    SciTech Connect

    Ansari, A.S.; Pandis, S.N.

    2000-01-01

    The hygroscopic nature of atmospheric aerosol has generally been associated with its inorganic fraction. In this study, a group contribution method is used to predict the water absorption of secondary organic aerosol (SOA). Compared against growth measurements of mixed inorganic-organic particles, this method appears to provide a first-order approximation in predicting SOA water absorption. The growth of common SOA species is predicted to be significantly less than common atmospheric inorganic salts such as (NH{sub 4}){sub 2}SO{sub 4} and NaCl. Using this group contribution method as a tool in predicting SOA water absorption, an integrated modeling approach is developed combining available SOA and inorganic aerosol models to predict overall aerosol behavior. The effect of SOA on water absorption and nitrate partitioning between the gas and aerosol phases is determined. On average, it appears that SOA accounts for approximately 7% of total aerosol water and increases aerosol nitrate concentrations by approximately 10%. At high relative humidity and low SOA mass fractions, the role of SOA in nitrate partitioning and its contribution to total aerosol water is negligible. However, the water absorption of SOA appears to be less sensitive to changes in relative humidity than that of inorganic species, and thus at low relative humidity and high SOA mass fraction concentrations, SOA is predicted to account for approximately 20% of total aerosol water and a 50% increase in aerosol nitrate concentrations. These findings could improve the results of modeling studies where aerosol nitrate has often been underpredicted.

  10. Water absorption dependent photoconductivity of a freestanding polymer bridge.

    PubMed

    Kim, Daeyoung; Choi, Jaewu

    2010-06-23

    The photo-response of a freestanding constricted polymeric solid-state bridge of water soluble sodium poly[2-(3-thienyl)-ethoxy-4-butylsulfonate] (SPTEBS) was studied as a function of water vapor pressure. The dark current dramatically increases with water vapor pressure higher than 12 Torr. Surprisingly, under light illumination, the short-circuit current of the polymeric solid-state bridge decreases with increasing water vapor pressure so that, above 12 Torr of water vapor pressure, the short-circuit current under the light illumination is even lower than the dark current. This negative photo-response of the polymeric solid-state bridge is attributed to the self-doping by hydration of the polymer and the de-doping, possibly the result of photo-induced desorption of adsorbed water molecules.

  11. Interrelation between the crystallinity of polysaccharides and water absorption

    NASA Astrophysics Data System (ADS)

    Prusov, A. N.; Prusova, S. M.; Radugin, M. V.; Zakharov, A. G.

    2014-05-01

    The maximum sorption of water and its vapors is calculated using experimental data from calorimetric and effusion studies of flax, wood, and cotton cellulose. X-day diffraction is used to determine the crystallinity of cellulose samples. The equations relating crystallinity ( X) with maximum sorption and the enthalpy of interaction between cellulose and water are presented. Experimental results and the literature data on water sorption by chitin, chitosan and other polysaccharides show that our equations for calculating crystallinity are correct.

  12. Water vapor absorption into amorphous sucrose-poly(vinyl pyrrolidone) and trehalose-poly(vinyl pyrrolidone) mixtures.

    PubMed

    Zhang, J; Zografi, G

    2001-09-01

    Previous studies from this laboratory suggested that a solution model (Flory-Huggins equation) modified by a free volume model (Vrentas equation) could satisfactorily describe water absorption into an amorphous solid composed of a sugar or a polymer. This paper has extended the studies of single solutes to binary mixtures of trehalose-and sucrose-poly(vinyl pyrrolidone) (trehalose-PVP and sucrose-PVP, respectively) either co-lyophilized or individually lyophilized and then physically mixed. Water vapor absorption isotherms of the binary mixtures were determined at 30 degrees C. Co-lyophilized PVP-sugar mixtures take up essentially the same amount of water as predicted by the weight average of individual isotherms, whereas sugar crystallization is significant retarded in the molecular dispersions. The sugar-PVP interaction, as reflected in the Flory-Huggins chi interaction parameter, was estimated by fitting the high relative pressure (p/p(0)) region of the isotherm, at which the system is in a liquid state, with a three-component Flory-Huggins-type model. The estimated sugar-water PVP-water, and sugar-PVP interaction parameters suggest that the solute-water interactions are not significantly affected by the sugar-PVP interaction; that is, the solute-water interaction parameters in a binary solute system are similar to those in the corresponding single solute systems. Based on these interaction parameters, the sucrose-PVP interaction appears to be stronger than that of trehalose-PVP. Manipulation of the interaction parameters suggest that the water vapor absorption isotherm is not a sensitive indicator of possible sugar-PVP interactions. Density, glass transition temperature, T(g), and the heat capacity change, DeltaC(p), at T(g) were determined to estimate the excess water absorption energy due to the plasticizing effect of water using the structural relaxation model, as described by Vrentas. Results suggest that PVP is a better antiplasticizer for sucrose than for

  13. Whey protein hydrolysates enhance water absorption in the perfused small intestine of anesthetized rats.

    PubMed

    Ito, Kentaro; Yamaguchi, Makoto; Noma, Teruyuki; Yamaji, Taketo; Itoh, Hiroyuki; Oda, Munehiro

    2016-08-01

    We evaluated the effect of whey protein hydrolysates (WPH) on the water absorption rate in the small intestine using a rat small intestine perfusion model. The rate was significantly higher with 5 g/L WPH than with 5 g/L soy protein hydrolysates or physiological saline (p < 0.05). WPH dose-dependently increased the water absorption rate in the range of 1.25-10.0 g/L. WPH showed a significantly higher rate than an amino acid mixture whose composition was equal to that of WPH (p < 0.05). The addition of 4-aminomethylbenzoic acid, an inhibitor of PepT1, significantly suppressed WPH's enhancement of water absorption (p < 0.05). The rate of water absorption was significantly correlated with that of peptides/amino acids absorption in WPH (r = 0.82, p < 0.01). These data suggest that WPH have a high water absorption-promoting effect, to which PepT1 contributes.

  14. Water absorption, dimensional change and radial pressure in resin matrix dental restorative materials.

    PubMed

    McCabe, John F; Rusby, Sandra

    2004-08-01

    The purpose of this work was to study the relationship between water absorption, dimensional change (swelling) under cavity constraint and radial stress generation in resin matrix dental restorative materials. Water absorption was determined on disc specimens whilst swelling was determined on samples of materials restrained within cavities cut in cast polymethylmethacrylate and pressure generated was determined using a 'push-out' test. Four commercially available resin matrix materials were used. A giomer material gave significantly greater water absorption than two compomers and a fluoride releasing composite (p<0.05). The giomer material was the only material which produced a significant degree of swelling (p<0.05) when restrained within a cavity. The giomer product produced the greatest radial pressure (over 20 MPa in 1 month) following water storage, however a significant pressure generation was also observed for other materials despite their much lower water absorption values. The mechanism of water absorption and the amount of water absorbed determine the dimensional changes and radial pressure generated by resin matrix materials in a moist environment.

  15. Wetting and absorption of water drops on Nafion films.

    PubMed

    Goswami, Sharonmoyee; Klaus, Shannon; Benziger, Jay

    2008-08-19

    Water drops on Nafion films caused the surface to switch from being hydrophobic to being hydrophilic. Contact angle hysteresis of >70 degrees between advancing and receding values were obtained by the Wilhelmy plate technique. Sessile drop measurements were consistent with the advancing contact angle; the sessile drop contact angle was 108 degrees . Water drop adhesion, as measured by the detachment angle on an inclined plane, showed much stronger water adhesion on Nafion than Teflon. Sessile water and methanol drops caused dry Nafion films to deflect. The flexure went through a maximum with time. Flexure increased with contact area of the drop, but was insensitive to the film thickness. Methanol drops spread more on Nafion and caused larger film flexure than water. The results suggest that the Nafion surface was initially hydrophobic but water and methanol drops caused hydrophilic sulfonic acid domains to be drawn to the Nafion surface. Local swelling of the film beneath the water drop caused the film to buckle. The maximum flexure is suggested to result from motion of a water swelling front through the Nafion film.

  16. Leaf and stem maximum water storage capacity of herbaceous plants in a mountain meadow

    NASA Astrophysics Data System (ADS)

    Wohlfahrt, Georg; Bianchi, Karin; Cernusca, Alexander

    2006-03-01

    Leaf and stem maximum water storage capacities of nine dominant species (three graminoids and six herbs) from a mountain meadow were investigated employing two different methods—submersing of and spraying at phytoelements, respectively. The resulting maximum water storage capacities were in overall good agreement with literature. The submersing method yielded significantly lower values as compared to the spraying method, but, using in situ dew measurements, it could not be conclusively determined which method is to be preferred. Significant correlations between maximum water storage capacity and several morphological parameters could be found both across species and within species, yet these relationships usually possessed relatively little predictive power and were not consistent across species. It is concluded that other plant characteristics than those investigated in the present study are responsible for determining differences between species and that the dependence of the maximum water storage capacities on morphological factors is highly species-specific.

  17. Absorption Spectra of Water Clusters Calculated Using Density Functional Theory

    DTIC Science & Technology

    2013-07-10

    calculated bond paths, i.e., bond critical point (BCP), ring critical point ( RCP ) and cage critical point (CCP), the AIMQB atomic properties. Shown in...point (BCP), ring critical point ( RCP ) and cage critical point (CCP). Randomly Distributed Water BCP RCP CCP 2 H2O 5 0 0 5 H2O 16 2 0 12 H2O...paths for liquid water comprising a cluster. Bond critical point (BCP), ring critical point ( RCP ) and cage critical point (CCP). Liquid Water

  18. Capacity factor analysis for evaluating water and sanitation infrastructure choices for developing communities.

    PubMed

    Bouabid, Ali; Louis, Garrick E

    2015-09-15

    40% of the world's population lacks access to adequate supplies of water and sanitation services to sustain human health. In fact, more than 780 million people lack access to safe water supplies and about 2.5 billion people lack access to basic sanitation. Appropriate technology for water supply and sanitation (Watsan) systems is critical for sustained access to these services. Current approaches for the selection of Watsan technologies in developing communities have a high failure rate. It is estimated that 30%-60% of Watsan installed infrastructures in developing countries are not operating. Inappropriate technology is a common explanation for the high rate of failure of Watsan infrastructure, particularly in lower-income communities (Palaniappan et al., 2008). This paper presents the capacity factor analysis (CFA) model, for the assessment of a community's capacity to manage and sustain access to water supply and sanitation services. The CFA model is used for the assessment of a community's capacity to operate, and maintain a municipal sanitation service (MSS) such as, drinking water supply, wastewater and sewage treatment, and management of solid waste. The assessment of the community's capacity is based on seven capacity factors that have been identified as playing a key role in the sustainability of municipal sanitation services in developing communities (Louis, 2002). These capacity factors and their constituents are defined for each municipal sanitation service. Benchmarks and international standards for the constituents of the CFs are used to assess the capacity factors. The assessment of the community's capacity factors leads to determine the overall community capacity level (CCL) to manage a MSS. The CCL can then be used to assist the community in the selection of appropriate Watsan technologies for their MSS needs. The selection is done from Watsan technologies that require a capacity level to operate them that matches the assessed CCL of the

  19. In vivo absorption comparison of nanotechnology-based silybin tablets with its water-soluble derivative.

    PubMed

    Xu, Di; Ni, Rui; Sun, Wei; Li, Luk Chiu; Mao, Shirui

    2015-04-01

    In this study, the in vivo oral absorption of a nanocrystal tablet formulation of a BCS II poorly water-soluble drug was compared with that of its water-soluble salt form. Silybin is used as the model drug, and its nanosuspension was prepared by high-pressure homogenization. Effect of process and formulation parameters on properties of the nansuspensions was investigated. Dried powder of the nanosuspension was prepared by spray drying and used for preparing tablets. A pharmacokinetic study was performed in Beagle dogs to compare the absorption for tablets of silybin nanocrystals and silybin meglumine. In vivo absorption of nanocrystal silybin tablet in Beagle dogs was determined. X-ray powder diffraction results indicated that silybin existed in a crystalline state after homogenization. In vivo absorption study in rats showed that the peroral absorption of silybin was enhanced remarkably by decreasing particle size. In vivo absorption of nanocrystal silybin tablet in Beagle dogs was comparable with that of the commercially available tablet of the water-soluble salt form of silybin. In conclusion, it is possible to increase the bioavailability of poorly soluble drugs by preparing its water-soluble derivative.

  20. Methods for analysis of selected metals in water by atomic absorption

    USGS Publications Warehouse

    Fishman, Marvin J.; Downs, Sanford C.

    1966-01-01

    This manual describes atomic-absorption-spectroscopy methods for determining calcium, copper, lithium, magnesium, manganese, potassium, sodium, strontium and zinc in atmospheric precipitation, fresh waters, and brines. The procedures are intended to be used by water quality laboratories of the Water Resources Division of the U.S. Geological Survey. Detailed procedures, calculations, and methods for the preparation of reagents are given for each element along with data on accuracy, precision, and sensitivity. Other topics discussed briefly are the principle of atomic absorption, instrumentation used, and special analytical techniques.

  1. Dynamics of Water Absorption and Evaporation During Methanol Droplet Combustion in Microgravity

    NASA Technical Reports Server (NTRS)

    Hicks, Michael C.; Dietrich, Daniel L.; Nayagam, Vedha; Williams, Forman A.

    2012-01-01

    The combustion of methanol droplets is profoundly influenced by the absorption and evaporation of water, generated in the gas phase as a part of the combustion products. Initially there is a water-absorption period of combustion during which the latent heat of condensation of water vapor, released into the droplet, enhances its burning rate, whereas later there is a water-evaporation period, during which the water vapor reduces the flame temperature suffciently to extinguish the flame. Recent methanol droplet-combustion experiments in ambient environments diluted with carbon dioxide, conducted in the Combustion Integrated Rack on the International Space Station (ISS), as a part of the FLEX project, provided a method to delineate the water-absorption period from the water-evaporation period using video images of flame intensity. These were obtained using an ultra-violet camera that captures the OH* radical emission at 310 nm wavelength and a color camera that captures visible flame emission. These results are compared with results of ground-based tests in the Zero Gravity Facility at the NASA Glenn Research Center which employed smaller droplets in argon-diluted environments. A simplified theoretical model developed earlier correlates the transition time at which water absorption ends and evaporation starts. The model results are shown to agree reasonably well with experiment.

  2. Carbon nanotube membranes with ultrahigh specific adsorption capacity for water desalination and purification.

    PubMed

    Yang, Hui Ying; Han, Zhao Jun; Yu, Siu Fung; Pey, Kin Leong; Ostrikov, Kostya; Karnik, Rohit

    2013-01-01

    Development of technologies for water desalination and purification is critical to meet the global challenges of insufficient water supply and inadequate sanitation, especially for point-of-use applications. Conventional desalination methods are energy and operationally intensive, whereas adsorption-based techniques are simple and easy to use for point-of-use water purification, yet their capacity to remove salts is limited. Here we report that plasma-modified ultralong carbon nanotubes exhibit ultrahigh specific adsorption capacity for salt (exceeding 400% by weight) that is two orders of magnitude higher than that found in the current state-of-the-art activated carbon-based water treatment systems. We exploit this adsorption capacity in ultralong carbon nanotube-based membranes that can remove salt, as well as organic and metal contaminants. These ultralong carbon nanotube-based membranes may lead to next-generation rechargeable, point-of-use potable water purification appliances with superior desalination, disinfection and filtration properties.

  3. Deriving in situ phytoplankton absorption for bio-optical productivity models in turbid waters

    NASA Astrophysics Data System (ADS)

    Oliver, Matthew J.; Schofield, Oscar; Bergmann, Trisha; Glenn, Scott; Orrico, Cristina; Moline, Mark

    2004-07-01

    As part of Hyperspectral Coupled Ocean Dynamics Experiment, a high-resolution hydrographic and bio-optical data set was collected from two cabled profilers at the Long-Term Ecosystem Observatory (LEO). Upwelling- and downwelling-favorable winds and a buoyant plume from the Hudson River induced large changes in hydrographic and optical structure of the water column. An absorption inversion model estimated the relative abundance of phytoplankton, colored dissolved organic matter (CDOM) and detritus, as well as the spectral exponential slopes of CDOM and detritus from in situ WET Labs nine-wavelength absorption/attenuation meter (ac-9) absorption data. Derived optical weights were proportional to the parameter concentrations and allowed for their absorptions to be calculated. Spectrally weighted phytoplankton absorption was estimated using modeled spectral irradiances and the phytoplankton absorption spectra inverted from an ac-9. Derived mean spectral absorption of phytoplankton was used in a bio-optical model estimating photosynthetic rates. Measured radiocarbon uptake productivity rates extrapolated with water mass analysis and the bio-optical modeled results agreed within 20%. This approach is impacted by variability in the maximum quantum yield (ϕmax) and the irradiance light-saturation parameter (Ek(PAR)). An analysis of available data shows that ϕmax variability is relatively constrained in temperate waters. The variability of Ek(PAR) is greater in temperate waters, but based on a sensitivity analysis, has an overall smaller impact on water-column-integrated productivity rates because of the exponential decay of light. This inversion approach illustrates the utility of bio-optical models in turbid coastal waters given the measurements of the bulk inherent optical properties.

  4. Analytical simulation of water system capacity reliability, 1. Modified frequency-duration analysis

    NASA Astrophysics Data System (ADS)

    Hobbs, Benjamin F.; Beim, Gina K.

    1988-09-01

    The problem addressed is the computation of the unavailability and expected unserved demand of a water supply system having random demand, finished water storage, and unreliable capacity components. Examples of such components include pumps, treatment plants, and aqueducts. Modified frequency-duration analysis estimates these reliability statistics by, first, calculating how often demand exceeds available capacity and, second, comparing the amount of water in storage with how long such capacity deficits last. This approach builds upon frequency-duration methods developed by the power industry for analyzing generation capacity deficits. Three versions of the frequency-duration approach are presented. Two yield bounds to system unavailability and unserved demand and the third gives an estimate of their true values between those bounds.

  5. Water absorption of poly(methyl methacrylate) containing 4-methacryloxyethyl trimellitic anhydride.

    PubMed

    Unemori, Masako; Matsuya, Yoko; Matsuya, Shigeki; Akashi, Akane; Akamine, Akifumi

    2003-04-01

    The amount of water absorption of poly(methyl methacrylate) (PMMA) containing 0, 1, 3 and 5 wt% of an adhesive monomer, 4-methacryloxyethyl trimellitic anhydride (4-META), was measured at 7 degrees C, 37 degrees C and 60 degrees C. After the water uptake reached equilibrium in specimens, they were desorbed to obtain a constant value and the absorption process was repeated. Mass changes in the second desorption were recorded for the storage temperatures of 37 degrees C and 60 degrees C. Multiple regression analyses were conducted on three independent variables, 4-META concentration, storage temperature and absorption-desorption cycle. A statistically significant relationship was found between the maximum water uptake and 4-META concentration, while there was no relationship between the maximum water uptake and diffusion coefficient obtained using the Fick's law. The negative relationship in the latter did not support the free space theory. The significant and positive relationship between the maximum water uptake and 4-META concentration demonstrates that water molecules diffuse through the formation of a hydrogen bond at polar sites. The maximum water uptake was not influenced by temperature, while the diffusion coefficient increased with the rise in temperature. The activation energy was 41-47 and 50-53 kJ/mol in the first and second absorption tests, respectively.

  6. Monitoring of Water Content And Frozen State by using Millimeter Wave Absorption Features

    NASA Astrophysics Data System (ADS)

    Mizuno, Maya; Shindo, Kenji; Ogawa, Yuichi; Otani, Chiko; Kawase, Kodo

    In this research, we built an experimental setup for measuring the water content in plants and food, and for determining the water/ice state of a sample. The setup consists of a 35 GHz Gunn oscillator producing about 10 mW of output power, two horn antennas and a power meter. We have checked that the absorption of a leaf is directly proportional to its water content, and we could show how changes of the water content depend on photosynthesis, by intermittent illumination with a white fluorescent lamp. In another direction of research, we verified that the difference in the absorption coefficients for water and ice is significant, and we could discriminate and monitor the frozen state of water and food material. All these experiments demonstrate the possibility of applying millimeter waves to fields such as botany, agriculture, and food industry.

  7. Effects of sodium polyacrylate on water retention and infiltration capacity of a sandy soil.

    PubMed

    Zhuang, Wenhua; Li, Longguo; Liu, Chao

    2013-01-01

    Based on the laboratory study, the effects of sodium polyacrylate (SP) was investigated at 5 rates of 0, 0.08, 0.2, 0.5, and 1%, on water retention, saturated hydraulic conductivity(Ks), infiltration characteristic and water distribution profiles of a sandy soil. The results showed that water retention and available water capacity effectively increased with increasing SP rate. The Ks and the rate of wetting front advance and infiltration under certain pond infiltration was significantly reduced by increasing SP rate, which effectively reduced water in a sandy soil leaking to a deeper layer under the plough layer. The effect of SP on water distribution was obviously to the up layer and very little to the following deeper layers. Considering both the effects on water retention and infiltration capacity, it is suggested that SP be used to the sandy soil at concentrations ranging from 0.2 to 0.5%.

  8. Emergency membrane contactor based absorption system for ammonia leaks in water treatment plants.

    PubMed

    Shao, Jiahui; Fang, Xuliang; He, Yiliang; Jin, Qiang

    2008-01-01

    Abstract Because of the suspected health risks of trihalomethanes (THMs), more and more water treatment plants have replaced traditional chlorine disinfection process with chloramines but often without the proper absorption system installed in the case of ammonia leaks in the storage room. A pilot plant membrane absorption system was developed and installed in a water treatment plant for this purpose. Experimentally determined contact angle, surface tension, and corrosion tests indicated that the sulfuric acid was the proper choice as the absorbent for leaking ammonia using polypropylene hollow fiber membrane contactor. Effects of several operating conditions on the mass transfer coefficient, ammonia absorption, and removal efficiency were examined, including the liquid concentration, liquid velocity, and feed gas concentration. Under the operation conditions investigated, the gas absorption efficiency over 99.9% was achieved. This indicated that the designed pilot plant membrane absorption system was effective to absorb the leaking ammonia in the model storage room. The removal rate of the ammonia in the model storage room was also experimentally and theoretically found to be primarily determined by the ammonia suction flow rate from the ammonia storage room to the membrane contactor. The ammonia removal rate of 99.9% was expected to be achieved within 1.3 h at the ammonia gas flow rate of 500 m3/h. The success of the pilot plant membrane absorption system developed in this study illustrated the potential of this technology for ammonia leaks in water treatment plant, also paved the way towards a larger scale application.

  9. Impact of MIE-Resonances on the Atmospheric Absorption of Water Clouds

    NASA Technical Reports Server (NTRS)

    Wiscombe, W.; Kinne, S.; Nussenzveig, H.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    Clouds strongly modulate radiative transfer processes in the Earth's atmosphere. Studies, which simulate bulk properties of clouds, such as absorption, require methods that accurately account for multiple scattering among individual cloud particles. Multiple scattering processes are well described by MIE-theory, if interacting particles have a spherical shape. This is a good assumption for water droplets. Thus, simulations for water clouds (especially for interactions with solar radiation) usually apply readily available MIE-codes. The presence of different drop-sizes, however, necessitates repetitive calculations for many sizes. The usual representation by a few sizes is likely to miss contributions from densely distributed, sharp resonances. Despite their usually narrow width, integrated over the entire size-spectrum of a cloud droplet distribution, the impact of missed resonances could add up. The consideration of these resonances tends to increase cloud extinction and cloud absorption. This mechanism for a larger (than by MIE-methods predicted) solar absorption has the potential to explain observational evidence of larger than predicted cloud absorption at solar wavelengths. The presentation will address the absorption impact of added resonances for typical properties of water clouds (e.g. drop size distributions, drop concentrations and cloud geometry). Special attention will be given to scenarios with observational evidence of law than simulated solar absorption; particularly if simultaneous measurements of cloud micro- and macrophysical properties are available.

  10. Modeling Climate-Water Impacts on Electricity Sector Capacity Expansion: Preprint

    SciTech Connect

    Cohen, S. M.; Macknick, J.; Averyt, K.; Meldrum, J.

    2014-05-01

    Climate change has the potential to exacerbate water availability concerns for thermal power plant cooling, which is responsible for 41% of U.S. water withdrawals. This analysis describes an initial link between climate, water, and electricity systems using the National Renewable Energy Laboratory (NREL) Regional Energy Deployment System (ReEDS) electricity system capacity expansion model. Average surface water projections from Coupled Model Intercomparison Project 3 (CMIP3) data are applied to surface water rights available to new generating capacity in ReEDS, and electric sector growth is compared with and without climate-influenced water rights. The mean climate projection has only a small impact on national or regional capacity growth and water use because most regions have sufficient unappropriated or previously retired water rights to offset climate impacts. Climate impacts are notable in southwestern states that purchase fewer water rights and obtain a greater share from wastewater and other higher-cost water resources. The electric sector climate impacts demonstrated herein establish a methodology to be later exercised with more extreme climate scenarios and a more rigorous representation of legal and physical water availability.

  11. The relationship between water vapor absorption and desorption by phospholipids and bilayer phase transitions.

    PubMed

    Mansour, Heidi M; Zografi, George

    2007-02-01

    Water vapor absorption and desorption at 25 degrees C and phase transition temperatures of phospholipid bilayers were measured as a function of relative humidity (RH) to better understand how the patterns of water vapor absorption and desorption are linked to corresponding phase changes induced by the level of hydration. Comparisons were made of the dipalmitoyl and palmitoyloleyol esters of glycerol derivatized with phosphatidyl-choline, -glycerol, -ethanolamine and with phosphatidic acid. The results suggest that the extent of water vapor absorption and desorption at a given RH reflects the combined effects of water-polar group interaction and access of water to the polar region as controlled by intra- and interbilayer molecular packing and intermolecular attractive and repulsive interactions. The results further suggest that the extent of water vapor absorption and desorption over a range of relative humidities reflects the combined effects of the polar group's ability to interact with water, the access that water has to the polar groups as determined by molecular size and various intermolecular and intrabilayer forces of attraction and repulsion, and interbilayer interactions which influence the degree of order/disorder present in the overall solid-state structure. This behavior is also reflected in the changes observed in the various bilayer phase transition temperatures as a function of RH. Analyses of absorption isotherms suggests that after exceeding a critical RH, water initially interacting with these phospholipids most likely forms either stoichiometric or nonstoichiometric crystal hydrates, as with the disaturated derivatives, or hydrated mesophases, as with the gel states of the monounsaturated derivatives.

  12. Performance Evaluation of a 4.5 kW (1.3 Refrigeration Tons) Air-Cooled Lithium Bromide/Water Solar Powered (Hot-Water-Fired) Absorption Unit

    SciTech Connect

    Zaltash, Abdolreza; Petrov, Andrei Y; Linkous, Randall Lee; Vineyard, Edward Allan

    2007-01-01

    During the summer months, air-conditioning (cooling) is the single largest use of electricity in both residential and commercial buildings with the major impact on peak electric demand. Improved air-conditioning technology has by far the greatest potential impact on the electric industry compared to any other technology that uses electricity. Thermally activated absorption air-conditioning (absorption chillers) can provide overall peak load reduction and electric grid relief for summer peak demand. This innovative absorption technology is based on integrated rotating heat exchangers to enhance heat and mass transfer resulting in a potential reduction of size, cost, and weight of the "next generation" absorption units. Rotartica Absorption Chiller (RAC) is a 4.5 kW (1.3 refrigeration tons or RT) air-cooled lithium bromide (LiBr)/water unit powered by hot water generated using the solar energy and/or waste heat. Typically LiBr/water absorption chillers are water-cooled units which use a cooling tower to reject heat. Cooling towers require a large amount of space, increase start-up and maintenance costs. However, RAC is an air-cooled absorption chiller (no cooling tower). The purpose of this evaluation is to verify RAC performance by comparing the Coefficient of Performance (COP or ratio of cooling capacity to energy input) and the cooling capacity results with those of the manufacturer. The performance of the RAC was tested at Oak Ridge National Laboratory (ORNL) in a controlled environment at various hot and chilled water flow rates, air handler flow rates, and ambient temperatures. Temperature probes, mass flow meters, rotational speed measuring device, pressure transducers, and a web camera mounted inside the unit were used to monitor the RAC via a web control-based data acquisition system using Automated Logic Controller (ALC). Results showed a COP and cooling capacity of approximately 0.58 and 3.7 kW respectively at 35 C (95 F) design condition for ambient

  13. Low-Dimensional Water on Ru(0001)Model System for X-ray Absorption Spectroscopy Studies of Liquid Water

    SciTech Connect

    Nordlund, D

    2012-02-14

    We present an x-ray absorption spectroscopy results for fully broken to a complete H-bond network of water molecules on Ru(0001) by varying the morphology from isolated water molecules via two-dimensional clusters to a fully covered monolayer as probed by scanning tunneling microscopy. The sensitivity of x-ray absorption to the symmetry of H-bonding is further elucidated for the amino (-NH{sub 2}) group in glycine adsorbed on Cu(110) where the E-vector is parallel either to the NH donating an H-bond or to the non-H-bonded NH. The results give further evidence for the interpretation of the various spectral features of liquid water and for the general applicability of x-ray absorption spectroscopy to analyze H-bonded systems.

  14. Tensile properties and water absorption of zein sheets plasticized with oleic and linoleic acids.

    PubMed

    Budi Santosa, F X; Padua, G W

    1999-05-01

    Corn zein has been investigated for fabrication of biodegradable packaging materials. Our objective was to investigate the effect of added plasticizers, oleic and linoleic acids, on tensile properties and water absorption of zein sheets. Moldable resins were precipitated from aqueous ethanol dispersions of zein and fatty acids and rolled into sheets of approximately 0.5 mm in thickness. To increase plasticization effects, zein-oleic acid sheets were replasticized by heating them in fatty acid baths. Plasticization resulted in flexible sheets of high clarity, low modulus, and high elongation and toughness, although low tensile strength. Water absorption of zein sheets was lowered by plasticization, attributed in part to reduced mass fraction of zein. Polymerization of linoleic acid may have sealed off pores on sheet surfaces, thus slowing water absorption.

  15. Parameterization of the Mie Extinction and Absorption Coefficients for Water Clouds.

    NASA Astrophysics Data System (ADS)

    Mitchell, David L.

    2000-05-01

    It was found that the anomalous diffraction approximation (ADA) could be made to approximate Mie theory for absorption and extinction in water clouds by parameterizing the missing physics: 1) internal reflection/refraction, 2) photon tunneling, and 3) edge diffraction. Tunneling here refers to processes by which tangential or grazing photons beyond the physical cross section of a spherical particle may be absorbed. Contributions of the above processes to extinction and/or absorption were approximated in terms of particle size, index of refraction, and wavelength. It was found that tunneling can explain most of the difference between ADA and Mie theory for water clouds in the thermal IR.The modified ADA yielded analytical expressions for the absorption and extinction efficiencies, Qabs and Qext, which were integrated over a gamma size distribution to yield expressions for the absorption and extinction coefficients, abs and ext. These coefficients were expressed in terms of the three gamma distribution parameters, which were related to measured properties of the size distribution: liquid water content, mean, and mass-median diameter. Errors relative to Mie theory for abs and ext were generally 10% for the effective radius range in water clouds of 5-30 m, for any wavelength in the solar or terrestrial spectrum. For broadband emissivities and absorptivities regarding terrestrial and solar radiation, the errors were less than 1.2% and 4%, respectively. The modified ADA dramatically reduces computation times relative to Mie theory while yielding reasonably accurate results.

  16. [Phytoplankton Light Absorption Properties During the Blooms in Adjacent Waters of the Changjiang Estuary].

    PubMed

    Liu, Yang-yang; Shen, Fang; Li, Xiu-zhen

    2015-06-01

    Phytoplankton dominant species and their light absorption properties during the blooms occurred in August 2013 in adjacent waters of the Changjiang Estuary were analyzed. The results showed that phytoplankton blooms broke out in 10 out of 34 investigation stations, among which diatom blooms occurred in 6 stations while 3 stations were predominated by dinoflagellate. Phytoplankton absorption coefficients of both bloom and non-bloom waters exhibited large variations, with respective ranges of 0.199-0.832 m(-1) and 0.012-0.109 m(-1), while phytoplankton specific absorption coefficients spanned much narrower range, with the average values of bloom and non-bloom waters being 0.023 and 0.035 m2 x mg(-1), respectively. When transitioned from bloom to non-bloom waters, the proportion of phytoplankton with larger cell size lowered while that of smaller phytoplankton elevated, causing a less extent of package effect and thus higher specific absorption coefficients. Distinctive absorption spectra were observed between different types of bloom (such as diatom and dinoflagellate blooms) with similar phytoplankton cell size, mostly attributed to distinctive accessory pigment composition. The ratios of diadinoxanthin and chlorophyll-c2 concentrations to chlorophyll-a concentration in dinoflagellate blooms were higher than those in diatom blooms, which largely contributed to the shoulder peaks at 465 nm in dinoflagellate blooms.

  17. Mechanisms of guanylin action on water and ion absorption at different regions of seawater eel intestine.

    PubMed

    Ando, Masaaki; Wong, Marty K S; Takei, Yoshio

    2014-09-15

    Guanylin (GN) inhibited water absorption and short-circuit current (Isc) in seawater eel intestine. Similar inhibition was observed after bumetanide, and the effect of bumetanide was abolished by GN or vice versa, suggesting that both act on the same target, Na(+)-K(+)-2Cl(-) cotransporter (NKCC), which is a key player for the Na(+)-K(+)-Cl(-) transport system responsible for water absorption in marine teleost intestine. However, effect of GN was always greater than that of bumetanide: 10% greater in middle intestine (MI) and 40% in posterior intestine (PI) for Isc, and 25% greater in MI and 34% in PI for water absorption. After treatment with GN, Isc decreased to zero, but 20-30% water absorption still remained. The remainder may be due to the Cl(-)/HCO3 (-) exchanger and Na(+)-Cl(-) cotransporter (NCC), since inhibitors for these transporters almost nullified the remaining water absorption. Quantitative PCR analysis revealed the presence of major proteins involved in water absorption; the NKCC2β and AQP1 genes whose expression was markedly upregulated after seawater acclimation. The SLC26A6 (anion exchanger) and NCCβ genes were also expressed in small amounts. Consistent with the inhibitors' effect, expression of NKCC2β was MI > PI, and that of NCCβ was MI < PI. The present study showed that GN not only inhibits the bumetanide-sensitive Na(+)-K(+)-Cl(-) transport system governed by NKCC2β, but also regulates unknown ion transporters different from GN-insensitive SLC26A6 and NCC. A candidate is cystic fibrosis transmembrane conductance regulator Cl(-) channel, as demonstrated in mammals, but its expression is low in eel intestine, and its role may be minor, as indicated by the small effect of its inhibitors.

  18. Water-Constrained Electric Sector Capacity Expansion Modeling Under Climate Change Scenarios

    NASA Astrophysics Data System (ADS)

    Cohen, S. M.; Macknick, J.; Miara, A.; Vorosmarty, C. J.; Averyt, K.; Meldrum, J.; Corsi, F.; Prousevitch, A.; Rangwala, I.

    2015-12-01

    Over 80% of U.S. electricity generation uses a thermoelectric process, which requires significant quantities of water for power plant cooling. This water requirement exposes the electric sector to vulnerabilities related to shifts in water availability driven by climate change as well as reductions in power plant efficiencies. Electricity demand is also sensitive to climate change, which in most of the United States leads to warming temperatures that increase total cooling-degree days. The resulting demand increase is typically greater for peak demand periods. This work examines the sensitivity of the development and operations of the U.S. electric sector to the impacts of climate change using an electric sector capacity expansion model that endogenously represents seasonal and local water resource availability as well as climate impacts on water availability, electricity demand, and electricity system performance. Capacity expansion portfolios and water resource implications from 2010 to 2050 are shown at high spatial resolution under a series of climate scenarios. Results demonstrate the importance of water availability for future electric sector capacity planning and operations, especially under more extreme hotter and drier climate scenarios. In addition, region-specific changes in electricity demand and water resources require region-specific responses that depend on local renewable resource availability and electricity market conditions. Climate change and the associated impacts on water availability and temperature can affect the types of power plants that are built, their location, and their impact on regional water resources.

  19. The Effect of Heat on Structural Characteristics and Water Absorption Behavior of Agave Fibers

    NASA Astrophysics Data System (ADS)

    Saikia, Dip

    2008-04-01

    The structural characteristics and water absorptions behavior agave fibers were investigated over a range of temperature by using XRD, IR, TG and gravimetric methods. Three distinct thermal processes were observed during heating the fiber in the temperature range 310-760 K in air, oxygen and nitrogen invariably. The cellulose structures of the fibers were unaffected on heating up to 450 K. The samples showed thermal decomposition processes beyond 500 K. Fibers displayed a two-stage diffusion behavior. The structural parameters and kinetic of water absorption of the fibers at specific temperatures were analyzed.

  20. Potential Water Retention Capacity as a Factor in Silage Effluent Control: Experiments with High Moisture By-product Feedstuffs.

    PubMed

    Razak, Okine Abdul; Masaaki, Hanada; Yimamu, Aibibula; Meiji, Okamoto

    2012-04-01

    The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, 'potential water retention capacity' (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer's grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (±10.3). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship.

  1. Specific absorption and backscatter coefficient signatures in southeastern Atlantic coastal waters

    NASA Astrophysics Data System (ADS)

    Bostater, Charles R., Jr.

    1998-12-01

    Measurements of natural water samples in the field and laboratory of hyperspectral signatures of total absorption and reflectance were obtained using long pathlength absorption systems (50 cm pathlength). Water was sampled in Indian River Lagoon, Banana River and Port Canaveral, Florida. Stations were also occupied in near coastal waters out to the edge of the Gulf Stream in the vicinity of Kennedy Space Center, Florida and estuarine waters along Port Royal Sound and along the Beaufort River tidal area in South Carolina. The measurements were utilized to calculate natural water specific absorption, total backscatter and specific backscatter optical signatures. The resulting optical cross section signatures suggest different models are needed for the different water types and that the common linear model may only appropriate for coastal and oceanic water types. Mean particle size estimates based on the optical cross section, suggest as expected, that particle size of oceanic particles are smaller than more turbid water types. The data discussed and presented are necessary for remote sensing applications of sensors as well as for development and inversion of remote sensing algorithms.

  2. Ab initio calculation of the electronic absorption spectrum of liquid water

    SciTech Connect

    Martiniano, Hugo F. M. C.; Galamba, Nuno; Cabral, Benedito J. Costa

    2014-04-28

    The electronic absorption spectrum of liquid water was investigated by coupling a one-body energy decomposition scheme to configurations generated by classical and Born-Oppenheimer Molecular Dynamics (BOMD). A Frenkel exciton Hamiltonian formalism was adopted and the excitation energies in the liquid phase were calculated with the equation of motion coupled cluster with single and double excitations method. Molecular dynamics configurations were generated by different approaches. Classical MD were carried out with the TIP4P-Ew and AMOEBA force fields. The BLYP and BLYP-D3 exchange-correlation functionals were used in BOMD. Theoretical and experimental results for the electronic absorption spectrum of liquid water are in good agreement. Emphasis is placed on the relationship between the structure of liquid water predicted by the different models and the electronic absorption spectrum. The theoretical gas to liquid phase blue-shift of the peak positions of the electronic absorption spectrum is in good agreement with experiment. The overall shift is determined by a competition between the O–H stretching of the water monomer in liquid water that leads to a red-shift and polarization effects that induce a blue-shift. The results illustrate the importance of coupling many-body energy decomposition schemes to molecular dynamics configurations to carry out ab initio calculations of the electronic properties in liquid phase.

  3. Ab initio calculation of the electronic absorption spectrum of liquid water.

    PubMed

    Martiniano, Hugo F M C; Galamba, Nuno; Cabral, Benedito J Costa

    2014-04-28

    The electronic absorption spectrum of liquid water was investigated by coupling a one-body energy decomposition scheme to configurations generated by classical and Born-Oppenheimer Molecular Dynamics (BOMD). A Frenkel exciton Hamiltonian formalism was adopted and the excitation energies in the liquid phase were calculated with the equation of motion coupled cluster with single and double excitations method. Molecular dynamics configurations were generated by different approaches. Classical MD were carried out with the TIP4P-Ew and AMOEBA force fields. The BLYP and BLYP-D3 exchange-correlation functionals were used in BOMD. Theoretical and experimental results for the electronic absorption spectrum of liquid water are in good agreement. Emphasis is placed on the relationship between the structure of liquid water predicted by the different models and the electronic absorption spectrum. The theoretical gas to liquid phase blue-shift of the peak positions of the electronic absorption spectrum is in good agreement with experiment. The overall shift is determined by a competition between the O-H stretching of the water monomer in liquid water that leads to a red-shift and polarization effects that induce a blue-shift. The results illustrate the importance of coupling many-body energy decomposition schemes to molecular dynamics configurations to carry out ab initio calculations of the electronic properties in liquid phase.

  4. Ab initio calculation of the electronic absorption spectrum of liquid water

    NASA Astrophysics Data System (ADS)

    Martiniano, Hugo F. M. C.; Galamba, Nuno; Cabral, Benedito J. Costa

    2014-04-01

    The electronic absorption spectrum of liquid water was investigated by coupling a one-body energy decomposition scheme to configurations generated by classical and Born-Oppenheimer Molecular Dynamics (BOMD). A Frenkel exciton Hamiltonian formalism was adopted and the excitation energies in the liquid phase were calculated with the equation of motion coupled cluster with single and double excitations method. Molecular dynamics configurations were generated by different approaches. Classical MD were carried out with the TIP4P-Ew and AMOEBA force fields. The BLYP and BLYP-D3 exchange-correlation functionals were used in BOMD. Theoretical and experimental results for the electronic absorption spectrum of liquid water are in good agreement. Emphasis is placed on the relationship between the structure of liquid water predicted by the different models and the electronic absorption spectrum. The theoretical gas to liquid phase blue-shift of the peak positions of the electronic absorption spectrum is in good agreement with experiment. The overall shift is determined by a competition between the O-H stretching of the water monomer in liquid water that leads to a red-shift and polarization effects that induce a blue-shift. The results illustrate the importance of coupling many-body energy decomposition schemes to molecular dynamics configurations to carry out ab initio calculations of the electronic properties in liquid phase.

  5. Spectral control of an alexandrite laser for an airborne water-vapor differential absorption lidar system

    NASA Technical Reports Server (NTRS)

    Ponsardin, Patrick; Grossmann, Benoist E.; Browell, Edward V.

    1994-01-01

    A narrow-linewidth pulsed alexandrite laser has been greatly modified for improved spectral stability in an aircraft environment, and its operation has been evaluated in the laboratory for making water-vapor differential absorption lidar measurements. An alignment technique is described to achieve the optimum free spectral range ratio for the two etalons inserted in the alexandrite laser cavity, and the sensitivity of this ratio is analyzed. This technique drastically decreases the occurrence of mode hopping, which is commonly observed in a tunable, two-intracavity-etalon laser system. High spectral purity (greater than 99.85%) at 730 nm is demonstrated by the use of a water-vapor absorption line as a notch filter. The effective cross sections of 760-nm oxygen and 730-nm water-vapor absorption lines are measured at different pressures by using this laser, which has a finite linewidth of 0.02 cm(exp -1) (FWHM). It is found that for water-vapor absorption linewidths greater than 0.04 cm(exp -1) (HWHM), or for altitudes below 10 km, the laser line can be considered monochromatic because the measured effective absorption cross section is within 1% of the calculated monochromatic cross section. An analysis of the environmental sensitivity of the two intracavity etalons is presented, and a closed-loop computer control for active stabilization of the two intracavity etalons in the alexandrite laser is described. Using a water-vapor absorption line as a wavelength reference, we measure a long-term frequency drift (approximately 1.5 h) of less than 0.7 pm in the laboratory.

  6. Water transport in plants: Mechanism of apparent changes in resistance during absorption.

    PubMed

    Boyer, J S

    1974-09-01

    Leaf water potentials were measured at various rates of water absorption in whole plants and detached leaves of well-watered Helianthus annuus L. The experiments were conducted in the steady state, where changes in leaf hydration did not affect the measurements but both the transpiration and growth components of absorption could be observed. Calculations of the total plant resistance to water transport showed that the resistance at low fluxes was about 30 times the resistance at high fluxes. Most of the change took place in the leaves, since similar changes could be demonstrated in detached leaves. The roots accounted for little of the change, since they varied in resistance by a factor of only 2.5 as flow varied.To ascertain whether the protoplasts of the leaves varied in resistance by an amount which could account for the change in resistance to water transport, measurements of rates of water movement in and out of the protoplasm were made when gradients in water potential between the protoplasts and the water source were varied. These showed that water movement did not occur at rates which could account for high rates of transpiration even when large differences in potential drove flow. The high temperature sensitivity of efflux confirmed that the leaf protoplasts limited flow in these experiments. When the edge of the leaf was excised and flow occurred primarily through the vascular system of the leaf, the resistance was much lower than in the protoplasts. It is therefore concluded that the leaf protoplasts represent a high resistance to water transport and that a considerable portion of the water involved in transpiration must bypass them.Calculations based on a model of water transport showed that the protoplast resistance was almost 30 times larger than the resistance of the path leading from the soil to the leaf protoplasts. The decrease in resistance of the leaves with increasing rates of absorption was therefore attributed to a decrease in water movement

  7. Effects of Weave Styles and Crimp Gradients on Damage Tolerance and Energy-Absorption Capacities of Woven Kevlar/Epoxy Composites

    DTIC Science & Technology

    2015-09-01

    ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Undersea Warfare Center Division 1176 Howell Street Newport, Rl 02841-1708 8. PERFORMING ORGANIZATION ...gradients (CGs) on the damage-tolerance levels and energy-absorption capacities of woven fabric-reinforced polymer (WFRP) composites. A comparative...Mechanics Fabrics Finite Element Analysis Functionally Graded Impact Fracture Kevlar Woven Composites Woven Fabric-Reinforced Polymer Composites 16

  8. Adaptive capacity indicators to assess sustainability of urban water systems - Current application.

    PubMed

    Spiller, Marc

    2016-11-01

    Sustainability is commonly assessed along environmental, societal, economic and technological dimensions. A crucial aspect of sustainability is that inter-generational equality must be ensured. This requires that sustainability is attained in the here and now as well as into the future. Therefore, what is perceived as 'sustainable' changes as a function of societal opinion and technological and scientific progress. A concept that describes the ability of systems to change is adaptive capacity. Literature suggests that the ability of systems to adapt is an integral part of sustainable development. This paper demonstrates that indicators measuring adaptive capacity are underrepresented in current urban water sustainability studies. Furthermore, it is discussed under which sustainability dimensions adaptive capacity indicators are lacking and why. Of the >90 indicators analysed, only nine are adaptive capacity indicators, of which six are socio-cultural, two technological, one economical and none environmental. This infrequent use of adaptive capacity indicators in sustainability assessments led to the conclusion that the challenge of dynamic and uncertain urban water systems is, with the exception of the socio-cultural dimension, not yet sufficiently reflected in the application of urban water sustainability indicators. This raises concerns about the progress towards urban water systems that can transform as a response variation and change. Therefore, research should focus on developing methods and indicators that can define, evaluate and quantify adaptive capacity under the economic, environmental and technical dimension of sustainability. Furthermore, it should be evaluated whether sustainability frameworks that focus on the control processes of urban water systems are more suitable for measuring adaptive capacity, than the assessments along environmental, economic, socio-cultural and technological dimensions.

  9. Enhanced load-carrying capacity of hairy surfaces floating on water.

    PubMed

    Xue, Yahui; Yuan, Huijing; Su, Weidong; Shi, Yipeng; Duan, Huiling

    2014-05-08

    Water repellency of hairy surfaces depends on the geometric arrangement of these hairs and enables different applications in both nature and engineering. We investigate the mechanism and optimization of a hairy surface floating on water to obtain its maximum load-carrying capacity by the free energy and force analyses. It is demonstrated that there is an optimum cylinder spacing, as a result of the compromise between the vertical capillary force and the gravity, so that the hairy surface has both high load-carrying capacity and mechanical stability. Our analysis makes it clear that the setae on water striders' legs or some insects' wings are in such an optimized geometry. Moreover, it is shown that surface hydrophobicity can further increase the capacity of a hairy surface with thick cylinders, while the influence is negligible when the cylinders are thin.

  10. Easy preparation of dietary fiber with the high water-holding capacity from food sources.

    PubMed

    Yamazaki, Eiji; Murakami, Kazumi; Kurita, Osamu

    2005-03-01

    Dietary fibers were prepared as alkali- and acid-insoluble fractions with chemical phosphorylation from Tossa jute (Corchorus olitorius), defatted soybean (Glycine max), and Shiitake (Lentinula edodes). The dietary fiber fractions treated with alkaline solution containing sodium metaphosphate had the lower protein content and higher total dietary fiber content than those of the preparations without phosphorylation. Alkaline extraction followed by phosphorylation led to a 1.5-fold increase in the water holding capacity of dietary fiber compared with no phosphorylation, whereas the binding capacity to bile acids of dietary fiber was almost the same. The alkali- and acid-insoluble extraction with phosphorylation provided an efficient preparation of water-insoluble dietary fiber with high-water holding capacity from various food sources.

  11. Enhanced load-carrying capacity of hairy surfaces floating on water

    PubMed Central

    Xue, Yahui; Yuan, Huijing; Su, Weidong; Shi, Yipeng; Duan, Huiling

    2014-01-01

    Water repellency of hairy surfaces depends on the geometric arrangement of these hairs and enables different applications in both nature and engineering. We investigate the mechanism and optimization of a hairy surface floating on water to obtain its maximum load-carrying capacity by the free energy and force analyses. It is demonstrated that there is an optimum cylinder spacing, as a result of the compromise between the vertical capillary force and the gravity, so that the hairy surface has both high load-carrying capacity and mechanical stability. Our analysis makes it clear that the setae on water striders' legs or some insects' wings are in such an optimized geometry. Moreover, it is shown that surface hydrophobicity can further increase the capacity of a hairy surface with thick cylinders, while the influence is negligible when the cylinders are thin. PMID:24808757

  12. Modeling water resources as a constraint in electricity capacity expansion models

    NASA Astrophysics Data System (ADS)

    Newmark, R. L.; Macknick, J.; Cohen, S.; Tidwell, V. C.; Woldeyesus, T.; Martinez, A.

    2013-12-01

    In the United States, the electric power sector is the largest withdrawer of freshwater in the nation. The primary demand for water from the electricity sector is for thermoelectric power plant cooling. Areas likely to see the largest near-term growth in population and energy usage, the Southwest and the Southeast, are also facing freshwater scarcity and have experienced water-related power reliability issues in the past decade. Lack of water may become a barrier for new conventionally-cooled power plants, and alternative cooling systems will impact technology cost and performance. Although water is integral to electricity generation, it has long been neglected as a constraint in future electricity system projections. Assessing the impact of water resource scarcity on energy infrastructure development is critical, both for conventional and renewable energy technologies. Efficiently utilizing all water types, including wastewater and brackish sources, or utilizing dry-cooling technologies, will be essential for transitioning to a low-carbon electricity system. This work provides the first demonstration of a national electric system capacity expansion model that incorporates water resources as a constraint on the current and future U.S. electricity system. The Regional Electricity Deployment System (ReEDS) model was enhanced to represent multiple cooling technology types and limited water resource availability in its optimization of electricity sector capacity expansion to 2050. The ReEDS model has high geographic and temporal resolution, making it a suitable model for incorporating water resources, which are inherently seasonal and watershed-specific. Cooling system technologies were assigned varying costs (capital, operations and maintenance), and performance parameters, reflecting inherent tradeoffs in water impacts and operating characteristics. Water rights supply curves were developed for each of the power balancing regions in ReEDS. Supply curves include costs

  13. Studies of Water Absorption Behavior of Plant Fibers at Different Temperatures

    NASA Astrophysics Data System (ADS)

    Saikia, Dip

    2010-05-01

    Moisture absorption of natural fiber plastic composites is one major concern in their outdoor applications. The absorbed moisture has many detrimental effects on the mechanical performance of these composites. A knowledge of the moisture diffusivity, permeability, and solubility is very much essential for the application of natural fibers as an excellent reinforcement in polymers. An effort has been made to study the water absorption behavior of some natural fibers such as bowstring hemp, okra, and betel nut at different temperatures to improve the long-term performance of composites reinforced with these fibers. The gain in moisture content in the fibers due to water absorption was measured as a function of exposure time at temperatures ranging from 300 K to 340 K. The thermodynamic parameters of the sorption process, such as diffusion coefficients and corresponding activation energies, were estimated.

  14. Absorption removal of sulfur dioxide by falling water droplets in the presence of inert solid particles

    NASA Astrophysics Data System (ADS)

    Liu, I.-Hung; Chang, Ching-Yuan; Liu, Su-Chin; Chang, I.-Cheng; Shih, Shin-Min

    An experimental analysis of the absorption removal of sulfur dioxide by the free falling water droplets containing the inert solid particles is presented. The wheat flour powder is introduced as the inert solid particles. Tests with and without the flour powder in the water droplets are examined. The mass fluxes and mass transfer coefficients of SO 2 for the cases with and without the flour powder are compared to elucidate the effects of the inert solid particles contained in the water droplets on the gas absorption. The results indicate aignificant difference between the two cases for the concentrations of the flour powder in the absorbent droplets ( Cs) within the ranges of the experimental conditions, namely 0.1 to 10 wt% flour powder in the absorbent droplets. In general, the inert solid particles of the flour powder as the impurities in the water droplets tend to decrease the SO 2 absorption rate for the experimental absorption system under investigation. Various values of Cs cause various levels of the interfacial resistance and affect the gas absorption rate. The interfacial resistance is recognized by introducing an interfacial mass transfer coefficient ks with its reciprocal being proportional to the magnitude of the interfacial resistance. The values of 1/ ks may be computed by the use of the equation 1/ ks=(1/ KOLs-1/ KOL), where KOLs and KOL are the overall liquid-phase mass transfer coefficients with and without the inert solid particles, respectively. The values of ks with Cs of 0.1 to 10 wt% are about 0.295-0.032 cms -1 for absorbing 1000-3000 ppmv SO 2 with the water droplets. This kind of information is useful for the SO 2 removal and the information of acid rain that the impurities of the inert solid particles contaminate the water droplets.

  15. Water absorption in PEEK and PEI matrices. Contribution to the understanding of water-polar group interactions

    NASA Astrophysics Data System (ADS)

    Courvoisier, E.; Bicaba, Y.; Colin, X.

    2016-05-01

    The water absorption in two aromatic linear polymers (PEEK and PEI) was studied between 10% and 90% RH at 30, 50 and 70°C. It was found that these polymers display classical Henry and Fick's behaviors. Moreover, they have very close values of equilibrium water concentration C∞ and water diffusivity D presumably because their respective polar groups establish molecular interactions of the same nature with water. This assumption was checked from a literature compilation of values of C∞ and D for a large variety of linear and tridimensional polymers containing a single type of polar group. It was then evidenced that almost all types of carbonyl group (in particular, those belonging to imides, amides and ketones) have the same molar contribution to water absorption, except those belonging to esters which are much less hydrophilic. Furthermore, hydroxyl and sulfone groups are much more hydrophilic than carbonyl groups so that their molar contribution is located on another master curve. On this basis, semi-empirical structure/water transport property relationships were proposed. It was found that C∞ increases exponentially with the concentration of polar groups (presumably because water is doubly bonded), but also with the intensity of their molecular interactions with water. In contrast, D is inversely proportional to C∞, which means that polar group-water interactions slow down the rate of water diffusion.

  16. Analysis and parameterization of absorption properties of northern Norwegian coastal water

    NASA Astrophysics Data System (ADS)

    Nima, Ciren; Frette, Øyvind; Hamre, Børge; Erga, Svein Rune; Chen, Yi-Chun; Zhao, Lu; Sørensen, Kai; Norli, Marit; Stamnes, Knut; Muyimbwa, Dennis; Ssenyonga, Taddeo; Ssebiyonga, Nicolausi; Stamnes, Jakob J.

    2017-02-01

    Coastal water bodies are generally classified as Case 2 water, in which non-algal particles (NAP) and colored dissolved organic matter (CDOM) contribute significantly to the optical properties in addition to phytoplankton. These three constituents vary independently in Case 2 water and tend to be highly variable in space and time. We present data from measurements and analyses of the spectral absorption due to CDOM, total suspended matter (TSM), phytoplankton, and NAP in high-latitude northern Norwegian coastal water based on samples taken in spring, summer, and autumn.

  17. Comparison of absorption properties of colored dissolved organic matter in six different case 2 water bodies

    NASA Astrophysics Data System (ADS)

    Nima, Ciren; Frette, Øyvind; Hamre, Børge; Erga, Svein Rune; Chen, Yi-Chun; Zhao, Lu; Muyimbwa, Dennis; Ssenyonga, Taddeo; Ssebiyonga, Nicolausi; Okullo, Willy; Stamnes, Knut; Stamnes, Jakob J.

    2017-02-01

    Colored Dissolved Organic Matter (CDOM) is one of the main factors controlling the penetration of solar radiation in Case 2 water and affecting satellite-based estimation of ocean color. We present absorption properties of CDOM sampled in 6 water bodies including three in Norway (Røst coastal water, Samnangerfjord, Lysefjord), two in China (Bohai Sea, Lake Namtso), and one in Africa (Lake Victoria). These locations, which range from near the equator to subarctic regions, include water types from oligotrophic to eutrophic, and altitudes from sea level to 4,700 m above sea level.

  18. Influence of Aloe vera on water absorption and enzymatic in vitro degradation of alginate hydrogel films.

    PubMed

    Pereira, Rúben F; Carvalho, Anabela; Gil, M H; Mendes, Ausenda; Bártolo, Paulo J

    2013-10-15

    This study investigates the influence of Aloe vera on water absorption and the in vitro degradation rate of Aloe vera-Ca-alginate hydrogel films, for wound healing and drug delivery applications. The influence of A. vera content (5%, 15% and 25%, v/v) on water absorption was evaluated by the incubation of the films into a 0.1 M HCl solution (pH 1.0), acetate buffer (pH 5.5) and simulated body fluid solution (pH 7.4) during 24h. Results show that the water absorption is significantly higher for films containing high A. vera contents (15% and 25%), while no significant differences are observed between the alginate neat film and the film with 5% of A. vera. The in vitro enzymatic degradation tests indicate that an increase in the A. vera content significantly enhances the degradation rate of the films. Control films, incubated in a simulated body fluid solution without enzymes, are resistant to the hydrolytic degradation, exhibiting reduced weight loss and maintaining its structural integrity. Results also show that the water absorption and the in vitro degradation rate of the films can be tailored by changing the A. vera content.

  19. DETERMINING BERYLLIUM IN DRINKING WATER BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROSCOPY

    EPA Science Inventory

    A direct graphite furnace atomic absorption spectroscopy method for the analysis of beryllium in drinking water has been derived from a method for determining beryllium in urine. Ammonium phosphomolybdate and ascorbic acid were employed as matrix modifiers. The matrix modifiers s...

  20. TPS/PCL composite reinforced with treated sisal fibers: property, biodegradation and water-absorption

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sisal fibers bleached with sodium-hydroxide followed by hydrogen peroxide treatment were incorporated in a thermoplastic starch;-polycaprolactone (TPS/PCL) blend via extrusion processing and examined for their property, biodegradability and water-absorption. Scanning electron microscopy revealed wel...

  1. Radiation modification of water absorption of cassava starch by acrylic acid/acrylamide

    NASA Astrophysics Data System (ADS)

    Kiatkamjornwong, Suda; Chomsaksakul, Wararuk; Sonsuk, Manit

    2000-10-01

    Graft copolymerizations of acrylamide and/or acrylic acid onto cassava starch by a simultaneous irradiation technique using gamma-rays as the initiator were studied with regard to various parameters of importance: the monomer-to-cassava starch ratio, total dose (kGy), dose rate (kGy h -1), acrylamide-to-acrylic acid ratio, and the addition of nitric acid and maleic acid as the additives. Grafting parameters were determined in relation to the water absorption of the saponified graft copolymer. The water absorption of the saponified graft copolymer in salt and buffer solutions of different ionic strengths was also measured, from which the superabsorbent properties are found to be pH sensitive. The starch graft copolymers of acrylamide and acrylic acid give higher water absorption than the starch graft copolymers of either acrylamide or acrylic acid alone. The porosity of the saponified starch graft copolymers prepared by the acrylamide/acrylic acid ratios of 70:30 and 50:50 was much higher than the porosity of copolymers in terms of fine networks. Ionic strength and multi-oxidation states of the saline and buffer solutions markedly decreased the water absorption of the saponified cassava starch grafted superabsorbent polymers.

  2. Ultraviolet-visible absorptive features of water extractable and humic fractions of animal manure and compost

    Technology Transfer Automated Retrieval System (TEKTRAN)

    UV-vis spectroscopy is a useful tool for characterizing water extractable or humic fractions of natural organic matter (WEOM). Whereas the whole UV-visible spectra of these fractions are more or less featureless, the specific UV absorptivity at 254 and 280 nm as well as spectral E2/E3 and E4/E6 rat...

  3. State-of-the-Art Review on Crystallization Control Technologies for water/LiBr Absorption Heat Pumps

    SciTech Connect

    Wang, Kai; Abdelaziz, Omar; Kisari, Padmaja; Vineyard, Edward Allan

    2011-01-01

    The key technical barrier to using water/lithium bromide (LiBr) as the working fluid in aircooled absorption chillers and absorption heat-pump systems is the risk of crystallization when the absorber temperature rises at fixed evaporating pressure. This article reviews various crystallization control technologies available to resolve this problem: chemical inhibitors, heat and mass transfer enhancement methods, thermodynamic cycle modifications, and absorption system-control strategies. Other approaches, such as boosting absorber pressure and J-tube technology, are reviewed as well. This review can help guide future efforts to develop water/LiBr air-cooled absorption chillers and absorption heatpump systems.

  4. Heat and Mass Diffusions in the Absorption of Water Vapor by Aqueous Solution of Lithium Bromide

    NASA Astrophysics Data System (ADS)

    Kashiwagi, Takao; Kurosaki, Yasuo; Nikai, Isao

    The recent development of absorption-type heat pump is highly essential from the viewpoint of extracting the effective energy from waste heat or solar energy. To increase the efficiency of energy conversion, it is important to improve the performance of absorbers. The objective of this paper is to obtain an increased understanding of the fine mechanisms of vapor absorption. A system combining holographic interferometry wity thermometry is adopted to observe the progress of one-dimensional water vapor absorption by aqueous solution of lithium bromide (LiBr) and also to measure the unsteady temperature and concentration distributions in the absorption process. The experiments are carried out under the condition that the solution surface is exposed to the saturated water vapor at reduced pressure, and the effects of LiBr mass concentration on absorption mechanism are examined in the concentration range 20-60 mass%. The interference fringes are analyzed to distinguish between the layers of heat conduction and mass diffusion. The temperature and concentration distributions thus determined experimentally are compared with numerical solutions obtained by the equations for unsteady heat conduction and mass diffusion taking into consideration the effect of heat by dilution, to give reasonable values of mass diffusivity hitherto remaining unknown. Especially in the range of 40-60 mass%, the mass diffusivity decreases extremely with the increase of mass concentration of LiBr and it falls down to 0.7-0.8×10-9 m2/s in case of 60 mass% solution.

  5. Water stress induces changes in polyphenol profile and antioxidant capacity in poplar plants (Populus spp.).

    PubMed

    Popović, B M; Štajner, D; Ždero-Pavlović, R; Tumbas-Šaponjac, V; Čanadanović-Brunet, J; Orlović, S

    2016-08-01

    This paper is aimed to characterize young poplar plants under the influence of water stress provoked by polyethileneglycol 6000 (PEG 6000). Three polar genotypes (M1, B229, and PE19/66) were grown in hydroponics and subjected to 100 and 200 mOsm PEG 6000 during six days. Polyphenol characterization, two enzymatic markers and antioxidant capacity in leaves and roots were investigated in stressed plants. Total phenol content, ferric reducing antioxidant capacity (FRAP) and DPPH antiradical power (DPPH ARP) were determined for estimating total antioxidant capacity. Polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) were determined as enzymatic markers. Polyphenol characterization of poplar samples was performed by HPLC-PDA analysis. All results were subjected to correlation analysis and principal component analysis (PCA). Inspite of the decrease of total phenol content in investigated genotypes, as well as total antioxidant capacity, some of polyphenols were affected by stress like flavonoids chrysin, myricetine, kaempferol and isoferulic acid in roots of B229 genotype (Populus deltoides). Genotype B229 also showed the increase of antioxidant capacity and PAL activity in root and leaves under stress what could be the indicator of the adaptability of poplar plants to water stress. Significant positive correlations were obtained between PAL, antioxidant capacity as well as phenolic acids among themselves. Chemometric evaluation showed close interdependence between flavonoids, FRAP, DPPH antiradical power and both investigated enzymes of polyphenol metabolism, PAL and PPO.

  6. Water vapour foreign-continuum absorption in near-infrared windows from laboratory measurements.

    PubMed

    Ptashnik, Igor V; McPheat, Robert A; Shine, Keith P; Smith, Kevin M; Williams, R Gary

    2012-06-13

    For a long time, it has been believed that atmospheric absorption of radiation within wavelength regions of relatively high infrared transmittance (so-called 'windows') was dominated by the water vapour self-continuum, that is, spectrally smooth absorption caused by H(2)O--H(2)O pair interaction. Absorption due to the foreign continuum (i.e. caused mostly by H(2)O--N(2) bimolecular absorption in the Earth's atmosphere) was considered to be negligible in the windows. We report new retrievals of the water vapour foreign continuum from high-resolution laboratory measurements at temperatures between 350 and 430 K in four near-infrared windows between 1.1 and 5 μm (9000-2000 cm(-1)). Our results indicate that the foreign continuum in these windows has a very weak temperature dependence and is typically between one and two orders of magnitude stronger than that given in representations of the continuum currently used in many climate and weather prediction models. This indicates that absorption owing to the foreign continuum may be comparable to the self-continuum under atmospheric conditions in the investigated windows. The calculated global-average clear-sky atmospheric absorption of solar radiation is increased by approximately 0.46 W m(-2) (or 0.6% of the total clear-sky absorption) by using these new measurements when compared with calculations applying the widely used MTCKD (Mlawer-Tobin-Clough-Kneizys-Davies) foreign-continuum model.

  7. Water vapor absorption into amorphous hydrophobic drug/poly(vinylpyrrolidone) dispersions.

    PubMed

    Crowley, Kieran J; Zografi, George

    2002-10-01

    Water vapor absorption isotherms were measured for three amorphous hydrophobic drug/poly(vinylpyrrolidone) (PVP) dispersions in the concentration range 10-90% w/w PVP. Experimental isotherms were compared to predicted isotherms calculated using each individual component isotherm multiplied by its weight fraction. Indomethacin (IMC)/PVP, ursodeoxycholic acid (UDCA)/PVP and indapamide (IDP)/PVP amorphous dispersions all exhibited experimental isotherms reduced relative to predicted isotherms indicating that dispersion formation altered the water vapor absorption properties of the individual components. For all three drug/PVP systems, deviation from predicted water uptake was greatest close to the 1:1 drug:PVP monomer composition, indicating that intermolecular interaction in amorphous dispersions affects the water uptake properties of the individual components. Using dry glass transition temperature (T(g)) data, the extent of drug/PVP interaction was shown to be greatest in the IDP/PVP system, which could explain why the largest reduction in water vapor absorption was found in this system. The plasticizing effect of absorbed water varied according to dry dispersion PVP content in all systems and the resulting nonideal changes in free volume, calculated using the Vrentas model, were greatest close to the 1:1 drug:PVP monomer composition. A three-component Flory-Huggins model successfully predicted isotherms for IMC/PVP compositions from 60 to 90% w/w PVP and identified an IMC-PVP interaction parameter chi in the range 1.27-1.49, values that suggest poor homogeneity of mixing in the dry system. These data indicate that amorphous dispersion formation causes both chemical and physical changes in the individual amorphous components that can have a significant effect on their water vapor absorption properties.

  8. Absorption properties of high-latitude Norwegian coastal water: The impact of CDOM and particulate matter

    NASA Astrophysics Data System (ADS)

    Nima, Ciren; Frette, Øyvind; Hamre, Børge; Erga, Svein Rune; Chen, Yi-Chun; Zhao, Lu; Sørensen, Kai; Norli, Marit; Stamnes, Knut; Stamnes, Jakob J.

    2016-09-01

    We present data from measurements and analyses of the spectral absorption due to colored dissolved organic matter (CDOM), total suspended matter (TSM), phytoplankton, and non-algal particles (NAP) in high-latitude northern Norwegian coastal water based on samples taken in spring, summer, and autumn. The Chlorophyll-a (Chl-a) concentration was found to vary significantly with season, whereas regardless of season CDOM was found to be the dominant absorber for wavelengths shorter than 600 nm. The absorption spectral slope S350-500 for CDOM varied between 0.011 and 0.022 nm-1 with mean value and standard deviation given by (0.015 ± 0.002) nm-1. The absorption spectral slope was found to be strongly dependent on the wavelength interval used for fitting. On average, S280-500 was found to be 43% higher than S350-500. A linear relationship was found between the base 10 logarithm of the absorption coefficient at 440 nm [log(ag(440))] and S350-500. Regardless of season, phytoplankton were the dominant component of the TSM absorption indicating little influence from land drainage. The mean values of the Chl-a specific absorption coefficient of phytoplankton aph*(λ) at 440 nm and 676 nm were 0.052 m2 mg-1 and 0.023 m2 mg-1, respectively, and aph*(λ) was found to vary with season, being higher in summer and autumn than in spring. The absorption spectral slope SNAP, which is the spectral slope of absorption spectrum for non-algal particles, was lower than that for European coastal water in general. It varied between 0.0048 and 0.022 nm-1 with mean value and standard deviation given by (0.0083-1 ± 0.003) nm-1. Comparisons of absorption coefficients measured in situ using an ac-9 instrument with those measured in the laboratory from water samples show a good agreement.

  9. Cd-Resistant Strains of B. cereus S5 with Endurance Capacity and Their Capacities for Cadmium Removal from Cadmium-Polluted Water.

    PubMed

    Wu, Huiqing; Wu, Qingping; Wu, Guojie; Gu, Qihui; Wei, Linting

    2016-01-01

    The goal of this study was to identify Cd-resistant bacterial strains with endurance capacity and to evaluate their ability to remove cadmium ions from cadmium-polluted water. The Bacillus cereusS5 strain identified in this study had the closest genetic relationship with B. cereus sp. Cp1 and performed well in the removal of Cd2+ions from solution. The results showed that both the live and dead biomasses of the Cd2+-tolerant B. cereus S5 strain could absorb Cd2+ ions in solution but that the live biomass of the B. cereus S5 strain outperformed the dead biomass at lower Cd2+concentrations. An analysis of the cadmium tolerance genes of B. cereus S5 identified ATPase genes that were associated with cadmium tolerance and involved in the ATP pumping mechanism. The FTIR spectra revealed the presence of amino, carboxyl and hydroxyl groups on the pristine biomass and indicated that the cadmium ion removal ability was related to the structure of the strain. The maximum absorption capacity of the B. cereus S5 strain in viable spore biomass was 70.16 mg/g (dry weight) based on a pseudo-second-order kinetic model fit to the experimental data. The Langmuir and Langmuir-Freundlich isotherm adsorption models fit the cadmium ion adsorption data well, and the kinetic curves indicated that the adsorption rate was second-order. For Cd2+ concentrations (mg/L) of 1-109 mg/L, good removal efficiency (>80%) was achieved using approximately 3.48-10.3 g/L of active spore biomass of the B. cereus S5 strain. A cadmium-tolerant bacteria-activated carbon-immobilized column could be used for a longer duration and exhibited greater treatment efficacy than the control column in the treatment of cadmium-polluted water. In addition, a toxicity assessment using mice demonstrated that the biomass of the B. cereus S5 strain and its fermentation products were non-toxic. Thus, the isolated B. cereus S5 strain can be considered an alternative biological adsorbent for use in emergency responses to severe

  10. Cd-Resistant Strains of B. cereus S5 with Endurance Capacity and Their Capacities for Cadmium Removal from Cadmium-Polluted Water

    PubMed Central

    Wu, Huiqing; Wu, Qingping; Wu, Guojie; Gu, Qihui; Wei, Linting

    2016-01-01

    The goal of this study was to identify Cd-resistant bacterial strains with endurance capacity and to evaluate their ability to remove cadmium ions from cadmium-polluted water. The Bacillus cereusS5 strain identified in this study had the closest genetic relationship with B. cereus sp. Cp1 and performed well in the removal of Cd2+ions from solution. The results showed that both the live and dead biomasses of the Cd2+-tolerant B. cereus S5 strain could absorb Cd2+ ions in solution but that the live biomass of the B. cereus S5 strain outperformed the dead biomass at lower Cd2+concentrations. An analysis of the cadmium tolerance genes of B. cereus S5 identified ATPase genes that were associated with cadmium tolerance and involved in the ATP pumping mechanism. The FTIR spectra revealed the presence of amino, carboxyl and hydroxyl groups on the pristine biomass and indicated that the cadmium ion removal ability was related to the structure of the strain. The maximum absorption capacity of the B. cereus S5 strain in viable spore biomass was 70.16 mg/g (dry weight) based on a pseudo-second-order kinetic model fit to the experimental data. The Langmuir and Langmuir-Freundlich isotherm adsorption models fit the cadmium ion adsorption data well, and the kinetic curves indicated that the adsorption rate was second-order. For Cd2+ concentrations (mg/L) of 1–109 mg/L, good removal efficiency (>80%) was achieved using approximately 3.48–10.3 g/L of active spore biomass of the B. cereus S5 strain. A cadmium-tolerant bacteria-activated carbon-immobilized column could be used for a longer duration and exhibited greater treatment efficacy than the control column in the treatment of cadmium-polluted water. In addition, a toxicity assessment using mice demonstrated that the biomass of the B. cereus S5 strain and its fermentation products were non-toxic. Thus, the isolated B. cereus S5 strain can be considered an alternative biological adsorbent for use in emergency responses to

  11. Simulation of water environmental capacity and pollution load reduction using QUAL2K for water environmental management.

    PubMed

    Zhang, Ruibin; Qian, Xin; Yuan, Xingcheng; Ye, Rui; Xia, Bisheng; Wang, Yulei

    2012-12-07

    In recent years, water quality degradation associated with rapid socio-economic development in the Taihu Lake Basin, China, has attracted increasing attention from both the public and the Chinese government. The primary sources of pollution in Taihu Lake are its inflow rivers and their tributaries. Effective water environmental management strategies need to be implemented in these rivers to improve the water quality of Taihu Lake, and to ensure sustainable development in the region. The aim of this study was to provide a basis for water environmental management decision-making. In this study, the QUAL2K model for river and stream water quality was applied to predict the water quality and environmental capacity of the Hongqi River, which is a polluted tributary in the Taihu Lake Basin. The model parameters were calibrated by trial and error until the simulated results agreed well with the observed data. The calibrated QUAL2K model was used to calculate the water environmental capacity of the Hongqi River, and the water environmental capacities of COD(Cr) NH(3)-N, TN, and TP were 17.51 t, 1.52 t, 2.74 t and 0.37 t, respectively. The results showed that the NH(3)-N, TN, and TP pollution loads of the studied river need to be reduced by 50.96%, 44.11%, and 22.92%, respectively to satisfy the water quality objectives. Thus, additional water pollution control measures are needed to control and reduce the pollution loads in the Hongqi River watershed. The method applied in this study should provide a basis for water environmental management decision-making.

  12. Potential Water Retention Capacity as a Factor in Silage Effluent Control: Experiments with High Moisture By-product Feedstuffs

    PubMed Central

    Razak, Okine Abdul; Masaaki, Hanada; Yimamu, Aibibula; Meiji, Okamoto

    2012-01-01

    The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, ‘potential water retention capacity’ (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer’s grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (±10.3). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship. PMID:25049587

  13. Reduction of Auxin Transport Capacity with Age and Internal Water Deficits in Cotton Petioles 1

    PubMed Central

    Davenport, Thomas L.; Morgan, Page W.; Jordan, Wayne R.

    1980-01-01

    Auxin transport was examined in leaf petioles taken from the upper, middle, and lower leaf canopy of large cotton plants. The ability of petioles to transport auxin decreased with age (position) of the leaves. Plant water deficit reduced transport regardless of age. These correlations support the view that reduced transport capacity of petioles plays a significant role in the induction of abscission of lower or older leaves during water deficits. PMID:16661278

  14. Influence of temperature and turbidity on water COD detection by UV absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhou, Kun-peng; Bi, Wei-hong; Zhang, Qi-hang; Fu, Xing-hu; Wu, Guo-qing

    2016-11-01

    Ultraviolet (UV) absorption spectroscopy is used to detect the concentration of water chemical oxygen demand (COD). The UV absorption spectra of COD solutions are analyzed qualitatively and quantitatively. The partial least square (PLS) algorithm is used to model COD solution and the modeling results are compared. The influence of environmental temperature and turbidity is analyzed. These results show that the influence of temperature on the predicted value can be ignored. However, the change of turbidity can affect the detection results of UV spectra, and the COD detection error can be effectively compensated by establishing the single-element regression model.

  15. Water vapour and greenhouse trapping: The role of far infrared absorption

    NASA Astrophysics Data System (ADS)

    Sinha, Ashok; Harries, John E.

    Few observations have been made of atmospheric absorption across the far infra-red. Yet water vapour absorption in this spectral region may significantly effect climate. The impact of far infra-red absorption is assessed by calculating the spectral variation of the total and water vapour greenhouse effects, for the sub-arctic winter (SAW) and tropical (TRP) standard atmospheres. Although the calculated efficiency of greenhouse trapping peaks outside of the far infra-red, the low strength there of the Planck function causes relatively small absolute forcings, except in the carbon dioxide and ozone bands. The sensitivity of the normalised greenhouse effect to water vapour concentration is largest in the far infra-red for the SAW atmosphere, and in the window region for the TRP. The sensitivity differs most between the two atmospheres in the far infra-red. Maximum water vapour greenhouse trapping arises in the far infra-red, over the middle/upper troposphere; in the SAW case the contribution from the water vapour continuum is virtually eliminated. Improved spectral observations and simulations at far infra-red wavelengths thus appear necessary to better understand the contemporary greenhouse effect, and to validate models of climate change.

  16. Finite element analysis and modeling of water absorption by date pits during a soaking process.

    PubMed

    Waezi-Zadeh, Motahareh; Ghazanfari, Ahmad; Noorbakhsh, Shahin

    2010-07-01

    Date pits for feed preparation or oil extraction are soaked in water to soften before milling or extrusion. Knowledge of water absorption by the date pits helps in better managing the soaking duration. In this research, the process of water absorption by date pits was modeled and analyzed using Fick's second law of diffusion, finite element approach, and Peleg model. The moisture content of the pits reached to its saturation level of 41.5% (wet basis) after 10 d. The estimated coefficient of diffusion was 9.89x10(-12) m(2)/s. The finite element model with a proposed ellipsoid geometry for a single date pit and the analytical model fitted better to the experimental data with R(2) of 0.98. The former model slightly overestimated the moisture content of the pits during the initial stages of the soaking and the latter model generally underestimated this variable through the entire stages of soaking process.

  17. Leaf photosynthetic rate of tropical ferns is evolutionarily linked to water transport capacity.

    PubMed

    Zhang, Shi-Bao; Sun, Mei; Cao, Kun-Fang; Hu, Hong; Zhang, Jiao-Lin

    2014-01-01

    Ferns usually have relatively lower photosynthetic potential than angiosperms. However, it is unclear whether low photosynthetic potential of ferns is linked to leaf water supply. We hypothesized that there is an evolutionary association of leaf water transport capacity with photosynthesis and stomatal density in ferns. In the present study, a series of functional traits relating to leaf anatomy, hydraulics and physiology were assessed in 19 terrestrial and 11 epiphytic ferns in a common garden, and analyzed by a comparative phylogenetics method. Compared with epiphytic ferns, terrestrial ferns had higher vein density (Dvein), stomatal density (SD), stomatal conductance (gs), and photosynthetic capacity (Amax), but lower values for lower epidermal thickness (LET) and leaf thickness (LT). Across species, all traits varied significantly, but only stomatal length (SL) showed strong phylogenetic conservatism. Amax was positively correlated with Dvein and gs with and without phylogenetic corrections. SD correlated positively with Amax, Dvein and gs, with the correlation between SD and Dvein being significant after phylogenetic correction. Leaf water content showed significant correlations with LET, LT, and mesophyll thickness. Our results provide evidence that Amax of the studied ferns is linked to leaf water transport capacity, and there was an evolutionary association between water supply and demand in ferns. These findings add new insights into the evolutionary correlations among traits involving carbon and water economy in ferns.

  18. Water holding capacity and evaporative loss from organic bedding materials used in livestock facilities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physical and chemical characteristics of organic bedding materials determine how well they will absorb and retain moisture and may influence the environment in livestock facilities where bedding is used. The objective of this study was to determine water holding capacity (WHC) and rate of evaporativ...

  19. Evaluation of electrical tomography to estimate soil water storage capacity in forested Karstic areas

    NASA Astrophysics Data System (ADS)

    Xie, Yingge; Chanzy, André

    2010-05-01

    Given that the large physical heterogeneous in forested karstic areas, water storage capacity estimation is always a difficulty. This study aims to evaluate the electrical resistivity tomography for the water storage capacity estimation in forested karstic areas. The electric tomography was implemented to estimate the stone volumic content and the bedrock depth determination. These caracteristics are combined to the water storage capacity of the fine earth made by the pressure chamber method. To estimate stone content we assumed that soil is a biphasic media with stones embedded in the fine earth media. We computed the effective resistivity with the Bussian (1983) law, which was evaluated against numerical results. It has been shown that the major factors were the electric resistivity of each phase, whereas the size of the stone had a lower impact. Based on independent measurements, we found an accuracy of about 20%. The bedrock apparition can be detected by establishing a threshold. This threshold is much lower than the resitivity made on rock sample due to cracks filled by conductive media. An estimation of the water storage capacity was then made by combining fine earth hydraulic characteristics, estimation of stone content and bedrock depth. An error assessment has shown that the spatial variability is larger than the estimation error. Bussian, A.E., 1983. Electrical conductance in a Porous-medium, Geophysics, 48(9): 1258-1268.

  20. Effect of wooden breast condition on water-holding capacity of broiler breast pectoralis major

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wooden breast condition (WBC) is an emerging muscle abnormality with broiler breast meat. Limited studies have shown that WBC significantly affects meat quality. The objective of this study was to evaluate the effects of WBC on water-holding capacity (WHC) of broiler breast pectoralis major. Broiler...

  1. [Actinobacteria and their odor-producing capacities in a surface water in Shanghai].

    PubMed

    Chen, Jiao; Bai, Xiao-hui; Lu, Ning; Wang, Xian-yun; Zhang, Yong-hui; Wu, Pan-cheng; Guo, Xin-chi

    2014-10-01

    The odor in raw water is one of the main sources of odor in drinking water. The occurrence of actinobacteria and their odor producing capacities in a reservoir in.Shanghai were investigated. Gauze's medium and membrane filtration were used for actinobacteria isolation. Through combined methods of 16S rRNA sequencing, colony and hyphae morphology, carbon source utilization, physiological and biochemical characteristics, 40 strains of actinobacteria were identified from the reservoir. Results showed that there were 38 Streptomyces, an Aeromicrobium and a Pseudonocardia. Liquid culture medium and the real reservoir water were used to test the odor producing capacity of these 40 strains of actinobacteria, and headspace solid phase microextraction (HS-SPME) and high resolution gas chromatography mass spectroscopy (GC/MS) were used to analyze the odor compounds 2-methylisoborneol (2-MIB) and geosmin (GSM) in the fermentation liquor. The test results showed that, the odor-producing capacities of these actinobacteria in different fermentation media showed different variation trends, even within the genera Streptomyces. The odor-producing capacity of actinobacteria in the liquid culture medium could not represent their states in the reservoir water or their actual odor contribution to the aquatic environment.

  2. Visible/near-infrared spectroscopy to predict pale broiler breast meat by measuring water holding capacity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Visible/Near-infrared spectroscopy (Vis/NIRS) was examined as a tool for rapidly determining water holding capacity (WHC) in broiler breast meat. Reflectance measurements for 85 breast filets were recorded over the 400 to 2498 nm wavelength range at 0.5 nm intervals and 32 scans. Chemometric analys...

  3. 21 CFR 130.12 - General methods for water capacity and fill of containers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false General methods for water capacity and fill of containers. 130.12 Section 130.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FOOD STANDARDS: GENERAL General Provisions § 130.12...

  4. Role of protein solubility in water-holding capacity of broiler breast meat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The role muscle protein denaturation plays in determining water-holding capacity (WHC) in broiler breast meat is not well understood. Alterations in muscle protein solubility due to postmortem pH and temperature decline can be used as indicators of protein denaturation. In order to determine the i...

  5. Water-holding capacity and protein denatunation in broiler breast meat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study was to investigate the impact of protein denaturation on water-holding capacity (WHC) in broiler breast meat. Breast fillets were collected at 2 h postmortem and segregated into two groups (low-WHC and high-WHC) based on pH and color. Protein solubility was measured at 6 and 24...

  6. Biochar impact on improving root growth and water retention capacity in Norfolk hard setting subsoil layer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Norfolk soil series is a well-drained soil used commonly for agricultural production in the Eastern Carolinas. Certain profile features such as a hard setting subsoil layer with high bulk density, low water holding capacity and meager soil fertility characteristics makes this soil less producti...

  7. Visible/near-infrared spectroscopy to predict water holding capacity in broiler breast meat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Visible/Near-infrared spectroscopy (Vis/NIRS) was examined as a tool for rapidly determining water holding capacity (WHC) in broiler breast meat. Both partial least squares (PLS) and principal component analysis (PCA) models were developed to relate Vis/NIRS spectra of 85 broiler breast meat sample...

  8. Parameterization of the Mie extinction and absorption coefficients for water clouds

    SciTech Connect

    Mitchell, D.L.

    2000-05-01

    It was found that the anomalous diffraction approximation (ADA) could be made to approximate Mie theory for absorption and extinction in water clouds by parameterizing the missing physics: (1) internal reflection/refraction, (2) photon tunneling, and (3) edge diffraction. Tunneling here refers to processes by which tangential or grazing photons beyond the physical cross section of a spherical particle may be absorbed. Contributions of the above processes to extinction and/or absorption were approximated in terms of particle size, index of refraction, and wavelength. It was found that tunneling can explain most of the difference between ADA and Mie theory for water clouds in the thermal IR. The modified ADA yielded analytical expressions for the absorption and extinction efficiencies, Q{sub abs} and Q{sub ext}, which were integrated over a gamma size distribution to yield expressions for the absorption and extinction coefficients, {beta}{sub abs} and {beta}{sub ext}. These coefficients were expressed in terms of the three gamma distribution parameters, which were related to measured properties of the size distribution: liquid water content, mean, and mass-median diameter. Errors relative to Mie theory for {beta}{sub abs} and {beta}{sub ext} were generally {le}10% for the effective radius range in water clouds of 5--30 {micro}m, for any wavelength in the solar or terrestrial spectrum. For broadband emissivities and absorptivities regarding terrestrial and solar radiation, the errors were less than 1.2% and 4%, respectively. The modified ADA dramatically reduces computation times relative to Mie theory while yielding reasonably accurate results.

  9. Real-time monitoring of corks' water absorption using laser speckle temporal correlation

    NASA Astrophysics Data System (ADS)

    Nassif, Rana; Abou Nader, Christelle; Pellen, Fabrice; Le Jeune, Bernard; Le Brun, Guy; Abboud, Marie

    2015-08-01

    Physical and mechanical properties of cork allow it solving many types of problems and make it suitable for a wide range of applications. Our objective consists into studying cork's water absorption by analyzing the dynamic speckle field using the temporal correlation method. Experimental results show that the medium was inert at first with the absence of activity, and as the cap cork was more and more immersed into water, the presence of the activity becomes more significant. This temporal parameter revealed the sensibility of biospeckle method to monitor the amount of absorbed water by cork caps.

  10. Determination of traces of silver in waters by anion exchange and atomic absorption spectrophotometry

    USGS Publications Warehouse

    Chao, T.T.; Fishman, M. J.; Ball, J.W.

    1969-01-01

    A method has been developed for the accurate determination of 0.1-1 ??g of silver per liter of water. The method permits stabilization of silver in water without loss to container walls. Optimum conditions have been established for the complete recovery of silver from water with an anion-exchange column, for quantitative elution of silver from the resin, and for measurement of silver by atomic absorption spectrophotometry after chelation with ammonium pyrrolidine dithiocarbamate and extraction of the chelate with MIBK. Silver in the 1-10 ??g 1 range can be determined by extraction without pre-concentration on an ion-exchange resin. ?? 1969.

  11. Advances in Diode-Laser-Based Water Vapor Differential Absorption Lidar

    NASA Astrophysics Data System (ADS)

    Spuler, Scott; Repasky, Kevin; Morley, Bruce; Moen, Drew; Weckwerth, Tammy; Hayman, Matt; Nehrir, Amin

    2016-06-01

    An advanced diode-laser-based water vapor differential absorption lidar (WV-DIAL) has been developed. The next generation design was built on the success of previous diode-laser-based prototypes and enables accurate measurement of water vapor closer to the ground surface, in rapidly changing atmospheric conditions, and in daytime cloudy conditions up to cloud base. The lidar provides up to 1 min resolution, 150 m range resolved measurements of water vapor in a broad range of atmospheric conditions. A description of the instrument and results from its initial field test in 2014 are discussed.

  12. Inhibition of Ileal Water Absorption by Intraluminal Fatty Acids INFLUENCE OF CHAIN LENGTH, HYDROXYLATION, AND CONJUGATION OF FATTY ACIDS

    PubMed Central

    Ammon, Helmut V.; Phillips, Sidney F.

    1974-01-01

    The influence of fatty acids on ileal absorption of water, electrolytes, glucose, and taurocholate was examined in Thirty-Vella fistulas in five mongrel dogs. Fatty acid absorption also was measured. Segments of terminal ileum were perfused at steady state with isotonic electrolyte solutions containing 11.2 mM glucose, 4.5 mM taurocholate, and 0.1-5.0 mM fatty acid. Three C18 fatty acids, oleic acid, 10(9)-hydroxystearic acid, and ricinoleic acid, completely inhibited water absorption at 5 mM. Sodium, chloride, and potassium absorptions were inhibited in parallel with absorption of water. Differences between the potencies of C18 fatty acids were apparent when lesser concentrations were perfused. Dodecanoic and decanoic acids were as effective as C18 fatty acids at 5 mM but octanoic and hexanoic acids were ineffective. The polar group of C18 fatty acids was modified by conjugating oleic and ricinoleic acids with taurine. When these compounds and a substituted C18 fatty acid, p-n-decylbenzenesulfonate, were perfused, water absorption was also inhibited. Short-chain fatty acids (C3 and C4) and their hydroxylated derivatives were ineffective at 5 mM. When water absorption was inhibited, absorption of glucose and taurocholate was decreased. We speculate that the phenomenon of inhibition of water and electrolyte absorption by fatty acids may be relevant to steatorrhea and diarrhea in man. Images PMID:4808636

  13. Storage Capacity and Water Quality of Lake Ngardok, Babeldaob Island, Republic of Palau, 1996-98

    USGS Publications Warehouse

    Yeung, Chiu Wang; Wong, Michael F.

    1999-01-01

    A bathymetric survey conducted during March and April, 1996, determined the total storage capacity Lake Ngardok to be between 90 and 168 acre-feet. Elevation-surface area and elevation-capacity curves summarizing the current relations among elevation, surface area, and storage capacity were created from the bathymetric map. Rainfall and lake-elevation data collected from April 1996 to March 1998 indicated that lake levels correlated to rainfall values with lake elevation rising rapidly in response to heavy rainfall and then returning to normal levels within a few days. Mean lake elevation for the 22 month period of data was 59.5 feet which gives a mean storage capacity of 107 acre-feet and a mean surface area of 24.1 acre. A floating mat of reeds, which covered 58 percent of the lake surface area at the time of the bathymetric survey, makes true storage capacity difficult to estimate. Water-quality sampling during April 1996 and November 1997 indicated that no U.S. Environmental Protection Agency primary drinking-water standards were violated for analyzed organic and inorganic compounds and radionuclides. With suitable biological treatment, the lake water could be used for drinking-water purposes. Temperature and dissolved oxygen measurements indicated that Lake Ngardok is stratified. Given that air temperature on Palau exhibits little seasonal variation, it is likely that this pattern of stratification is persistent. As a result, complete mixing of the lake is probably rare. Near anaerobic conditions exist at the lake bottom. Low dissolved oxygen (3.2 milligrams per liter) measured at the outflow indicated that water flowing past the outflow was from the deep oxygen-depleted depths of the lake.

  14. Water vapor absorption coefficients in the 8-13-micron spectral region - A critical review

    NASA Technical Reports Server (NTRS)

    Grant, William B.

    1990-01-01

    Measurements of water vapor absorption coefficients in the thermal IR atmospheric window (8-13 microns) during the past 20 years obtained by a variety of techniques are reviewed for consistency and compared with computed values based on the AFGL spectral data tapes. The methods of data collection considered were atmospheric long path absorption with a CO2 laser or a broadband source and filters, a White cell and a CO2 laser or a broadband source and a spectrometer, and a spectrophone with a CO2 laser. Advantages and disadvantages of each measurement approach are given as a guide to further research. Continuum absorption has apparently been measured accurately to about the 5-10 percent level in five of the measurements reported.

  15. Mid-IR absorption sensing of heavy water using a silicon-on-sapphire waveguide.

    PubMed

    Singh, Neetesh; Casas-Bedoya, Alvaro; Hudson, Darren D; Read, Andrew; Mägi, Eric; Eggleton, Benjamin J

    2016-12-15

    We demonstrate a compact silicon-on-sapphire (SOS) strip waveguide sensor for mid-IR absorption spectroscopy. This device can be used for gas and liquid sensing, especially to detect chemically similar molecules and precisely characterize extremely absorptive liquids that are difficult to detect by conventional infrared transmission techniques. We reliably measure concentrations up to 0.25% of heavy water (D2O) in a D2O-H2O mixture at its maximum absorption band at around 4 μm. This complementary metal-oxide-semiconductor (CMOS) compatible SOS D2O sensor is promising for applications such as measuring body fat content or detection of coolant leakage in nuclear reactors.

  16. Capacity building in water demand management as a key component for attaining millennium development goals

    NASA Astrophysics Data System (ADS)

    Gumbo, Bekithemba; Forster, Laura; Arntzen, Jaap

    Successful water demand management (WDM) implementation as a component of integrated water resource management (IWRM) can play a significant role in the alleviation of poverty through more efficient use of available water resources. The urban population in Southern African cities is characterised by so-called ‘water poor’ communities who typically expend a high percentage of their household income on poor quality water. Usually they have no access to an affordable alternative source. Although WDM as a component of IWRM is not a panacea for poverty, it can help alleviate poverty by facilitating water services management by municipal water supply agencies (MWSAs) in the region. WDM is a key strategy for achieving the millennium development goals (MDGs) and, as such, should be given due attention in the preparation of national IWRM and water efficiency plans. Various studies in the Southern African region have indicated that capacity building is necessary for nations to develop IWRM and water-use efficiency plans to meet the targets set out in the MDGs. WDM education and training of water professionals and end-users is particularly important in developing countries, which are resource and information-access poor. In response to these findings, The World Conservation Union (IUCN) and its consulting partners, the Training and Instructional Design Academy of South Africa (TIDASA), and Centre for Applied Research (CAR) designed, developed and presented a pilot WDM Guideline Training Module for MWSAs as part of Phase II of IUCN’s Southern Africa regional WDM project. Pilot training was conducted in July 2004 in Lusaka, Zambia for a group of 36 participants involved in municipal water supply from nine Southern African countries. This paper looks at the links between building the capacity of professionals, operational staff and other role-players in the municipal water supply chain to implement WDM as part of broader IWRM strategies, and the subsequent potential for

  17. Climate Change and Water Infrastructure in Central Asia: adaptation capacities and institutional challenges

    NASA Astrophysics Data System (ADS)

    Abdullaev, Iskandar; Rakhmatullaev, Shavkat

    2014-05-01

    The paper discusses vulnerability areas of water sector in arid Central Asia due to climate change projections with particular focus on adaptation to sustainable operation of physical infrastructure capacities (from legal, institutional and technical aspects). Two types of technical installations are the main focus of this paper, i.e., electrical lift irrigation systems and water reservoirs. The first set of electrical lift infrastructure is strategic for delivering water to water users via pumps, diversion structures, vertical drainage facilities and groundwater boreholes; on the other hand, the primarily task of second set of structures is to accumulate the water resources for sectors of economy. In Central Asia, approximately, 20-50% of irrigation water is lifted, yet major of lift structures are in very poor technical conditions coupled with ever increasing of electricity tariffs. Furthermore, useful volumes capacities of water reservoirs are being severely diminished due to bio-physical geomorphologic processes, improper operational regimes and chronic financing for special in-house sedimentation surveys. Most importantly, the key argument is that irrigation sector should internalize its adaptation efforts, i.e., integrate renewable energy technologies, energy audit programs and lastly design comprehensive investment prioritization processes and programs. Otherwise, water sector will be at great risk for continued provision of fundamental services to the public, food security and industry

  18. Interaction between Bisphosphonates and Mineral Water: Study of Oral Risedronate Absorption in Rats.

    PubMed

    Itoh, Akihisa; Akagi, Yuuki; Shimomura, Hitoshi; Aoyama, Takao

    2016-01-01

    Bisphosphonates are antiosteoporotic agents prescribed for patients with osteoporosis. Drug package inserts for bisphosphonate supplements indicate that their bioavailability is reduced by high levels of metal cations (Ca(2+), Mg(2+), etc.). However, standards for these cations in water used for taking risedronate have not been defined. Here, we examined the effect of calcium and magnesium in mineral waters on the bioavailability of the third-generation bisphosphonate, risedronate, following oral administration in rats. As risedronate is unchanged and eliminated renally, risedronate absorption was estimated from the amount excreted in the urine. Risedronate was dissolved in mineral water samples and administered orally at 0.35 mg/kg. Urine samples were collected for 24 h after dosing. Risedronate was extracted from urine using ion-pair solid-phase cartridges and quantified by HPLC with UV detection (262 nm). Cumulative recovery of risedronate was calculated from the amount excreted in the urine. The 24-h recovery of risedronate from evian® (0.32±0.02% [mean±standard deviation (S.D.)], n=4) and Contrex(®) (0.22±0.05%) mineral waters was significantly lower than that from tap water (0.47±0.04%, p<0.01). Absorption of risedronate in calcium chloride and magnesium chloride aqueous solutions of the same hardness (822 mg/L) was 54% (0.27±0.04%) and 12% (0.51±0.08%) lower, respectively, compared with ultrapure water; suggesting that absorption of risedronate declines as the calcium concentration of mineral waters increases. Consumption of mineral waters containing high levels of calcium (80 mg/L or above), such as evian® and Contrex(®), is therefore not recommended when taking risedronate.

  19. Rhizophoraceae Mangrove Saplings Use Hypocotyl and Leaf Water Storage Capacity to Cope with Soil Water Salinity Changes

    PubMed Central

    Lechthaler, Silvia; Robert, Elisabeth M. R.; Tonné, Nathalie; Prusova, Alena; Gerkema, Edo; Van As, Henk; Koedam, Nico; Windt, Carel W.

    2016-01-01

    Some of the most striking features of Rhizophoraceae mangrove saplings are their voluminous cylinder-shaped hypocotyls and thickened leaves. The hypocotyls are known to serve as floats during seed dispersal (hydrochory) and store nutrients that allow the seedling to root and settle. In this study we investigate to what degree the hypocotyls and leaves can serve as water reservoirs once seedlings have settled, helping the plant to buffer the rapid water potential changes that are typical for the mangrove environment. We exposed saplings of two Rhizophoraceae species to three levels of salinity (15, 30, and 0–5‰, in that sequence) while non-invasively monitoring changes in hypocotyl and leaf water content by means of mobile NMR sensors. As a proxy for water content, changes in hypocotyl diameter and leaf thickness were monitored by means of dendrometers. Hypocotyl diameter variations were also monitored in the field on a Rhizophora species. The saplings were able to buffer rapid rhizosphere salinity changes using water stored in hypocotyls and leaves, but the largest water storage capacity was found in the leaves. We conclude that in Rhizophora and Bruguiera the hypocotyl offers the bulk of water buffering capacity during the dispersal phase and directly after settlement when only few leaves are present. As saplings develop more leaves, the significance of the leaves as a water storage organ becomes larger than that of the hypocotyl. PMID:27446125

  20. The water vapour self- and water-nitrogen continuum absorption in the 1000 and 2500 cm(-1) atmospheric windows.

    PubMed

    Baranov, Yu I; Lafferty, W J

    2012-06-13

    The pure water vapour and water-nitrogen continuum absorption in the 1000 and 2500 cm(-1) atmospheric windows has been studied using a 2 m base-length White-type multi-pass cell coupled with a BOMEM DA3-002 Fourier transform infrared spectrometer. The measurements were carried out at the National Institute of Standards and Technology (NIST, Gaithersburg, MD) over the course of several years (2004, 2006-2007, 2009). New data on the H(2)O:N(2) continuum in the 1000 cm(-1) window are presented and summarized along with the other experimental results and the continuum model. The experimental data reported on the water vapour continuum in these atmospheric windows basically agree with the most reliable laboratory data from the other sources. The MT_CKD (Mlawer-Tobin-Clough-Kneizys-Davies) continuum model significantly departs from the experimental data in both windows. The deviation observed includes the continuum magnitude, spectral behaviour and temperature dependence. In the 2500 cm(-1) region, the model does not allow for the nitrogen fundamental collision-induced absorption (CIA) band intensity enhancement caused by H(2)O:N(2) collisions and underestimates the actual absorption by over two orders of magnitude. The water vapour continuum interpretation as a typical CIA spectrum is reviewed and discussed.

  1. Water Absorption and HEMA Release of Resin-Modified Glass-Ionomers

    PubMed Central

    Beriat, Nilufer Celebi; Nalbant, Dilek

    2009-01-01

    Objectives The aim of this study was to evaluate the water absorption and the amount of hydroxyethyl metacrylate (HEMA) level released from various resin modified glass ionomer cements. Methods Advance, Vitremer and Protec-Cem resin modified glass ionomer cements were used to evaluate the HEMA release. Ten specimens were fabricated from each cement in 10 x 1 mm height. Thirty specimens were immersed in glass containers filled with 20 ml deionized water. 1 ml solution was taken from the container at 10 minutes, 1 hour, 24 hour and 7 days intervals from each group and analyzed with high performance liquid chromatography (HPLC) machine and the results are presented in ppm. The data were subjected to Kruskal-Wallis, Mann-Whitney and Wilcoxon tests at a 0.05 significance level. Results At all time intervals Vitremer showed highest HEMA release ( 10 min: 54.2 ppm; 1 h: 86.8 ppm; 24 h: 93.4 ppm) (P=0.0001). At the end of 10 minutes and first hour, following Vitremer, HEMA release was highest for Protec-Cem (10 min: 14.8 ppm; 1 h: 23.6 ppm) and then Advance (10 min: 5.5 ppm; 1 h: 18.8 ppm) (P<.05). Water absorption tests were performed according to the specifications of ISO 4049. Water absorption was highest for Vitremer and lowest for the Protec-Cem and the difference among cement groups was significant (P<.005). Conclusions Vitremer showed the highest HEMA release and water absorption values and Protec-Cem showed the lowest values. HEMA release by time was significant for Advance cement. This release may be relevant both to the risk of adverse pulpal responses in patients and to the risk of allergy in patients and dental personnel. PMID:19826597

  2. Effect of water on the physical properties and carbon dioxide capture capacities of liquid-like Nanoparticle Organic Hybrid Materials and their corresponding polymers.

    PubMed

    Petit, Camille; Bhatnagar, Sonali; Park, Ah-Hyung Alissa

    2013-10-01

    Binary systems composed of liquid-like Nanoparticle Organic Hybrid Materials (NOHMs) and the secondary fluid (i.e., water) were prepared, and their thermal stabilities, densities, viscosities, and CO2 absorption capacities were investigated. Recent work has suggested NOHMs as an alternative CO2 capture media with interesting chemical and physical tunability. Anhydrous CO2 capture solvents often degrade when they are exposed to water, while flue gas generally contains about 8-16% water. Thus, this study was conducted to investigate the effect of water on the NOHMs' properties relevant to CO2 capture as well as the chemical and thermal stabilities of H2O-loaded NOHMs. It was found that water acted as an antisolvent of NOHMs, and therefore, caused a decreased CO2 capture capacity. On the other hand, the results indicated that while water did not affect the NOHMs' thermal stability, it significantly helped lowering their density and viscosity. In order to investigate the effect of intermolecular interactions among two fluids on the density and viscosity, the excess volumes and viscosity deviations were calculated and correlated with Redlich-Kister equations. The trends revealed the existence of strong intermolecular interactions between water molecules and the poly(ethlyne glycol) component of NOHMs, which may have caused the drastic decrease in the NOHMs' viscosity with the addition of water.

  3. Water distribution in tofu and application of T2 relaxation measurements in determination of tofu's water-holding capacity.

    PubMed

    Li, Teng; Rui, Xin; Li, Wei; Chen, Xiaohong; Jiang, Mei; Dong, Mingsheng

    2014-08-27

    Low-field nuclear magnetic resonance (LF-NMR) was introduced for the elucidation of tofu in the present study. After multiexponential analysis of relaxation decays, three water fractions centered at about 1.5-2.6, 24-114, and 132-305 ms were detected and identified as T2b, T21, and T22, respectively. Principal component analysis (PCA) of the data revealed that sample aggregation was dependent on solubility of coagulants and contained anions. Stepwise centrifugation and microwave drying were employed as dehydration methods. Significant correlations were observed between T21 and T22 relaxation times and water-holding capacity (WHC) in both dehydration processes, which implied LF-NMR measurements could be an efficient method for determination and prediction of tofu's water-holding capacity. Ten linear equations that could be applied in prediction of WHC for tofu were reported. LF-NMR was suggested to be a powerful tool for the study of tofu.

  4. Calculation of heat capacities of light and heavy water by path-integral molecular dynamics

    NASA Astrophysics Data System (ADS)

    Shiga, Motoyuki; Shinoda, Wataru

    2005-10-01

    As an application of atomistic simulation methods to heat capacities, path-integral molecular dynamics has been used to calculate the constant-volume heat capacities of light and heavy water in the gas, liquid, and solid phases. While the classical simulation based on conventional molecular dynamics has estimated the heat capacities too high, the quantum simulation based on path-integral molecular dynamics has given reasonable results based on the simple point-charge/flexible potential model. The calculated heat capacities (divided by the Boltzmann constant) in the quantum simulation are 3.1 in the vapor H2O at 300 K, 6.9 in the liquid H2O at 300 K, and 4.1 in the ice IhH2O at 250 K, respectively, which are comparable to the experimental data of 3.04, 8.9, and 4.1, respectively. The quantum simulation also reproduces the isotope effect. The heat capacity in the liquid D2O has been calculated to be 10% higher than that of H2O, while it is 13% higher in the experiment. The results demonstrate that the path-integral simulation is a promising approach to quantitatively evaluate the heat capacities for molecular systems, taking account of quantum-mechanical vibrations as well as strongly anharmonic motions.

  5. Control of pulmonary absorption of water-soluble compounds by various viscous vehicles.

    PubMed

    Yamamoto, Akira; Yamada, Keigo; Muramatsu, Hideaki; Nishinaka, Asako; Okumura, Shigeki; Okada, Naoki; Fujita, Takuya; Muranishi, Shozo

    2004-09-10

    Effects of various viscous vehicles on the pulmonary absorption of water-soluble drugs were examined by an in situ pulmonary absorption experiment. Gelatin, polyvinylacohol (PVA), hydroxypropylcellose (HPC), chondroitin sulfate A sodium salt (CS), polyacrylic acid (PAA), methylcellulose #400 (MC400) and hyaluronic acid sodium salt (HA) were used as models of viscous vehicles. 5(6)-Carboxyfluorescein (CF) and fluorescein isothiocayanate-labeled dextran with an average molecular weight of 4000 (FD4) were used as water-soluble drugs. The plasma concentration of CF was controlled and regulated in the presence of these viscous vehicles, especially gelatin (1-5%) and polyvinyl alcohol (PVA) 1%. In the pharmacokinetic analysis, the Cmax values of CF significantly decreased, and its Tmax values increased in the presence of these viscous vehicles compared with the control. The MRT and MAT values of CF with these vehicles were significantly higher than those without these vehicles. Therefore, these findings indicated that the viscous vehicles were effective to regulate the absorption rate of CF. On the other hand, the pulmonary absorption of FD4 was not so much affected even in the presence of gelatin and PVA, although PVA slightly decreased MRT value, and significantly decreased Tmax value. Furthermore, we examined the release rate of CF from the cellulose tube containing various concentrations of gelatin. The release rate of CF from the cellulose tube with gelatin was inversely related to the viscosity of gelatin. In addition, the release rate of CF was inversely related to DeltaMAT (DeltaMAT = MATgel(MAT with gelatin)-MATsol(MAT without gelatin)) in the presence of varying concentrations of gelatin. These findings indicated that these viscous vehicles were effective to control the pulmonary absorption of CF, a water-soluble drug with low molecular weight and they might be useful to increase the local concentration of drugs in the lung.

  6. Drought planning and water allocation: an assessment of local capacity in Minnesota.

    PubMed

    Pirie, Rebecca L; de Loë, Rob C; Kreutzwiser, Reid

    2004-10-01

    Water allocation systems are challenged by hydrologic droughts, which reduce available water supplies and can adversely affect human and environmental systems. To address this problem, drought management mechanisms have been instituted in jurisdictions around the world. Historically, these mechanisms have involved a crisis management or reactive approach. An important trend during the past decade in places such as the United States has been a shift to a more proactive approach, emphasizing drought preparedness and local involvement. Unfortunately, local capacity for drought planning is highly variable, with some local governments and organizations proving to be more capable than others of taking on new responsibilities. This paper reports on a study of drought planning and water allocation in the State of Minnesota. Factors facilitating and constraining local capacity for drought planning were identified using in-depth key informant interviews with state officials and members of two small Minnesota cities, combined with an analysis of pertinent documentation. A key factor contributing to the effectiveness of Minnesota's system is a water allocation system with explicit priorities during shortages, and provisions for restrictions. At the same time, the requirement that water suppliers create Public Water Supply Emergency Conservation Plans (PWSECP) clarifies the roles and responsibilities of key local actors. Unfortunately, the research revealed that mandated PWSECP are not always implemented, and that awareness of drought and drought planning measures in general may be poor at the local level. From the perspective of the two cities evaluated, factors that contributed to local capacity included sound financial and human resources, and (in some cases) effective vertical and horizontal linkages. This analysis of experiences in Minnesota highlights problems that can occur when senior governments establish policy frameworks that increase responsibilities at the local

  7. Ammonia and ammonium hydroxide sensors for ammonia/water absorption machines: Literature review and data compilation

    NASA Astrophysics Data System (ADS)

    Anheier, N. C., Jr.; McDonald, C. E.; Cuta, J. M.; Cuta, F. M.; Olsen, K. B.

    1995-05-01

    This report describes an evaluation of various sensing techniques for determining the ammonia concentration in the working fluid of ammonia/water absorption cycle systems. The purpose was to determine if any existing sensor technology or instrumentation could provide an accurate, reliable, and cost-effective continuous measure of ammonia concentration in water. The resulting information will be used for design optimization and cycle control in an ammonia-absorption heat pump. Pacific Northwest Laboratory (PNL) researchers evaluated each sensing technology against a set of general requirements characterizing the potential operating conditions within the absorption cycle. The criteria included the physical constraints for in situ operation, sensor characteristics, and sensor application. PNL performed an extensive literature search, which uncovered several promising sensing technologies that might be applicable to this problem. Sixty-two references were investigated, and 33 commercial vendors were identified as having ammonia sensors. The technologies for ammonia sensing are acoustic wave, refractive index, electrode, thermal, ion-selective field-effect transistor (ISFET), electrical conductivity, pH/colormetric, and optical absorption. Based on information acquired in the literature search, PNL recommends that follow-on activities focus on ISFET devices and a fiber optic evanescent sensor with a colormetric indicator. The ISFET and fiber optic evanescent sensor are inherently microminiature and capable of in situ measurements. Further, both techniques have been demonstrated selective to the ammonium ion (NH4(+)). The primary issue remaining is how to make the sensors sufficiently corrosion-resistant to be useful in practice.

  8. Ammonia and ammonium hydroxide sensors for ammonia/water absorption machines: Literature review and data compilation

    SciTech Connect

    Anheier, N.C. Jr.; McDonald, C.E.; Cuta, J.M.; Cuta, F.M.; Olsen, K.B.

    1995-05-01

    This report describes an evaluation of various sensing techniques for determining the ammonia concentration in the working fluid of ammonia/water absorption cycle systems. The purpose of this work was to determine if any existing sensor technology or instrumentation could provide an accurate, reliable, and cost-effective continuous measure of ammonia concentration in water. The resulting information will be used for design optimization and cycle control in an ammonia-absorption heat pump. PNL researchers evaluated each sensing technology against a set of general requirements characterizing the potential operating conditions within the absorption cycle. The criteria included the physical constraints for in situ operation, sensor characteristics, and sensor application. PNL performed an extensive literature search, which uncovered several promising sensing technologies that might be applicable to this problem. Sixty-two references were investigated, and 33 commercial vendors were identified as having ammonia sensors. The technologies for ammonia sensing are acoustic wave, refractive index, electrode, thermal, ion-selective field-effect transistor (ISFET), electrical conductivity, pH/colormetric, and optical absorption. Based on information acquired in the literature search, PNL recommends that follow-on activities focus on ISFET devices and a fiber optic evanescent sensor with a colormetric indicator. The ISFET and fiber optic evanescent sensor are inherently microminiature and capable of in situ measurements. Further, both techniques have been demonstrated selective to the ammonium ion (NH{sub 4}{sup +}). The primary issue remaining is how to make the sensors sufficiently corrosion-resistant to be useful in practice.

  9. Water vapour absorption in the clear atmosphere of a Neptune-sized exoplanet.

    PubMed

    Fraine, Jonathan; Deming, Drake; Benneke, Bjorn; Knutson, Heather; Jordán, Andrés; Espinoza, Néstor; Madhusudhan, Nikku; Wilkins, Ashlee; Todorov, Kamen

    2014-09-25

    Transmission spectroscopy has so far detected atomic and molecular absorption in Jupiter-sized exoplanets, but intense efforts to measure molecular absorption in the atmospheres of smaller (Neptune-sized) planets during transits have revealed only featureless spectra. From this it was concluded that the majority of small, warm planets evolve to sustain atmospheres with high mean molecular weights (little hydrogen), opaque clouds or scattering hazes, reducing our ability to observe the composition of these atmospheres. Here we report observations of the transmission spectrum of the exoplanet HAT-P-11b (which has a radius about four times that of Earth) from the optical wavelength range to the infrared. We detected water vapour absorption at a wavelength of 1.4 micrometres. The amplitude of the water absorption (approximately 250 parts per million) indicates that the planetary atmosphere is predominantly clear down to an altitude corresponding to about 1 millibar, and sufficiently rich in hydrogen to have a large scale height (over which the atmospheric pressure varies by a factor of e). The spectrum is indicative of a planetary atmosphere in which the abundance of heavy elements is no greater than about 700 times the solar value. This is in good agreement with the core-accretion theory of planet formation, in which a gas giant planet acquires its atmosphere by accreting hydrogen-rich gas directly from the protoplanetary nebula onto a large rocky or icy core.

  10. Modeling the current and future capacity of water resources to meet water demands in the Ebro basin

    NASA Astrophysics Data System (ADS)

    Milano, Marianne; Ruelland, Denis; Dezetter, Alain; Fabre, Julie; Ardoin-Bardin, Sandra; Servat, Eric

    2013-09-01

    Worldwide studies have shown that the Mediterranean region is one of the most vulnerable areas to water crisis. The region is characterized by limited and unequally distributed water resources and increasing water demands. The Ebro catchment (85,000 km2, Spain) is representative of this context. Since the late 1970s, a negative trend in river discharge has been observed, attributed to a decrease in mean precipitation, and a rise in mean temperature and in water consumption. Finally, over 230 storage dams regulate river discharge. In this context, an integrated water resources modeling framework was developed to evaluate the current and future capacity of water resources to meet domestic and agricultural water demands as well as environmental flow requirements. The approach was driven by a conceptual rainfall-runoff model generating water supplies and by a demand driven storage dam model. The approach defines current pressures on water resources and evaluates future changes in water allocation in the medium term under climatic and water use scenarios, considering changes in population and in irrigated areas. Currently, water demands in the Ebro catchment are satisfied. In 2050, water resources are projected to decrease by 15-35% during spring and summer, leading to growing competition among users and severe water shortages for irrigated agriculture. This study provides an original approach to identify the most vulnerable regions to water use conflicts. It also highlights the interest of integrated modeling for complete analysis of the ability of water resources to meet water demands in complex change scenarios as a support for decision making.

  11. Possible impact of the atmospheric water vapor absorption on the total ozone amount

    NASA Astrophysics Data System (ADS)

    Makogon, Mikail M.; Nesmelova, Ljudmila I.; Rodimova, Olga B.

    2004-02-01

    The total ozone amount (TOA) is determined as a rule by classic spectrophotometric method: TOA is found from a measured difference of the atmospheric optical thicknesses at two specially selected wavelengths in the region 305-340 nm. In this region the aerosol and molecular scattering takes place and it is traditionally believed, that the molecular absorption in this spectral region is conditioned only by ozone. Researches performed in the Institute of Atmospheric Optics SB RAS at the end of 1980s have shown, that there is also gentle absorption of a water vapor in this region, which can make a contribution to the measured difference of atmospheric optical thicknesses and can result in some methodical error. Thus, the TOA value which is determined without considering the water vapor, may be overstated.

  12. Effects of irradiation on protein electrophoretic properties, water absorption and cooking quality of lentils.

    PubMed

    Celik, Süeda; Yalçin, Erkan; Başman, Arzu; Köksel, Hamit

    2004-12-01

    Effects of gamma irradiation at doses of 1 kGy, 5 kGy, and 10 kGy on water absorption properties, cooking quality and electrophoretic patterns of insoluble proteins of red and green lentil samples were investigated. The densitometric analysis indicated that the effects of irradiation on sodium dodecyl sulfate-polycrylamide gel electrophoresis patterns of red and green lentil proteins were not significant. Generally, a 1 kGy irradiation dose did not significantly affect the water absorption properties of the lentil samples while significant increases were observed at the 5 kGy level. The dry and wet cooking times were found to be significantly decreased, as the irradiation level increased in all red and green lentil samples.

  13. Water-controlled wealth of nations: Using Water Footprints to Estimate Nations Carrying Capacities and Demographic Sustainability

    NASA Astrophysics Data System (ADS)

    Suweis, Samir; Rinaldo, Andrea; Maritan, Amos; D'Odorico, Paolo

    2014-05-01

    Population growth is in general constrained by food production, which in turn depends on the access to water resources. At a country level, some populations use more water than they control because of their ability to import food and the virtual water required for its production. Here, we investigate the dependence of demographic growth on available water resources for exporting and importing nations. By quantifying the carrying capacity of nations based on calculations of the virtual water available through the food trade network, we point to the existence of a global water unbalance. We suggest that current export rates will not be maintained and consequently we question the long-run sustainability of the food trade system as a whole. Water rich regions are likely to soon reduce the amount of virtual water they export, thus leaving import-dependent regions without enough water to sustain their populations. We also investigate the potential impact of possible scenarios that might mitigate these effects through (1) cooperative interactions among nations whereby water rich countries maintain a tiny fraction of their food production available for export; (2) changes in consumption patterns; and (3) a positive feedback between demographic growth and technological innovations. We find that these strategies may indeed reduce the vulnerability of water-controlled societies.

  14. Effect of water and temperature on absorption of CO2 by amine-functionalized anion-tethered ionic liquids.

    PubMed

    Goodrich, Brett F; de la Fuente, Juan C; Gurkan, Burcu E; Lopez, Zulema K; Price, Erica A; Huang, Yong; Brennecke, Joan F

    2011-07-28

    Amine-functionalized anion-tethered ionic liquids (ILs) trihexyl(tetradecyl)phosphonium asparaginate [P(66614)][Asn], glutaminate [P(66614)][Gln], lysinate [P(66614)][Lys], methioninate [P(66614)][Met], prolinate [P(66614)][Pro], taurinate [P(66614)][Tau], and threoninate [P(66614)][Thr] were synthesized and investigated as potential absorbents for CO(2) capture from postcombustion flue gas. Their physical properties, including density, viscosity, glass transition temperature, and thermal decomposition temperature were determined. Furthermore, the CO(2) absorption isotherms of [P(66614)][Lys], [P(66614)][Tau], [P(66614)][Pro], and [P(66614)][Met] were measured using a volumetric method, and the results were modeled with two different Langmuir-type absorption models. The most important result of this study is that the viscosity of [P(66614)][Pro] only increased by a factor of 2 when fully complexed with 1 bar of CO(2) at room temperature. This is in stark contrast to the other chemically reacted ILs investigated here and all other amino acid-based ILs reported in the literature, which dramatically increase in viscosity, typically by 2 orders of magnitude, when complexed with CO(2). The unique behavior of [P(66614)][Pro] is likely due to its ring structure, which limits the number and availability of hydrogen atoms that can participate in a hydrogen bonding network. We found that water can be used to further reduce the viscosity of the CO(2)-complexed IL, while only slightly decreasing the CO(2) capacity. Finally, from temperature-dependent isotherms, we estimate a heat of absorption of -63 kJ/mol of CO(2) for the 1:1 reaction of CO(2) with [P(66614)][Pro], when we use the two-reaction model.

  15. Calculated slant-path absorption and distribution of atmospheric water vapor.

    PubMed

    Calfee, R F; Gates, D M

    1966-02-01

    A procedure is described for determining the amount and distribution of water vapor along a slant path through the atmosphere above 13.7 km. A multilayer analysis is used in which the transmittance of each layer is calculated and the accumulative effect obtained at the altitude of observation. The method depends upon the contribution of each line to the absorptance in a finite spectral region.

  16. Folic acid absorption determined by a single stool sample test--a double-isotope technique. The folic acid absorption capacity in children

    SciTech Connect

    Hjelt, K. )

    1989-10-01

    The fractional folic acid absorption (FAFol) was determined in 66 patients with various gastrointestinal diseases by a double-isotope technique, employing a single stool sample test (SSST) as well as a complete stool collection. The age of the patients ranged from 2.5 months to 16.8 years (mean 6.3 years). The test dose was administered orally and consisted of 50 micrograms of (3H)folic acid (monoglutamate) (approximately 20 muCi), carmine powder, and 2 mg 51CrCl3 (approximately 1.25 muCi) as the unabsorbable tracer. The whole-body radiation given to a 1-year-old child averaged 4.8 mrad only. The stool and napkin contents were collected and homogenized by the addition of 300 ml chromium sulfuric acid. A 300-ml sample of the homogenized stool and napkin contents, as well as 300 ml chromium sulfuric acid (75% vol/vol) containing the standards, were counted for the content of 51Cr in a broad-based well counter. The quantity of (3H)folic acid was determined by liquid scintillation, after duplicate distillation. Estimated by SSST, the FAFol, which employs the stool with the highest content of 51Cr corresponding to the most carmine-colored stool, correlated closely with the FAFol based on complete stool collection (r = 0.96, n = 39, p less than 0.0001). The reproducibility of FAFol determined by SSST was assessed from repeated tests in 18 patients. For a mean of 81%, the SD was 4.6%, which corresponded to a coefficient of variation of 5.7%.

  17. Core Knowledge Employee Creativity and Firm Performance: The Moderating Role of Riskiness Orientation, Firm Size, and Realized Absorptive Capacity

    ERIC Educational Resources Information Center

    Gong, Yaping; Zhou, Jing; Chang, Song

    2013-01-01

    In this study, we examine when creativity is positively or negatively related to firm performance. Building on the creation-implementation tension theorized in the literature and the attention capacity perspective, we argue that the relationship between creativity and firm performance is contingent on riskiness orientation, firm size, and realized…

  18. Optimization of urban water supply portfolios combining infrastructure capacity expansion and water use decisions

    NASA Astrophysics Data System (ADS)

    Medellin-Azuara, J.; Fraga, C. C. S.; Marques, G.; Mendes, C. A.

    2015-12-01

    The expansion and operation of urban water supply systems under rapidly growing demands, hydrologic uncertainty, and scarce water supplies requires a strategic combination of various supply sources for added reliability, reduced costs and improved operational flexibility. The design and operation of such portfolio of water supply sources merits decisions of what and when to expand, and how much to use of each available sources accounting for interest rates, economies of scale and hydrologic variability. The present research provides a framework and an integrated methodology that optimizes the expansion of various water supply alternatives using dynamic programming and combining both short term and long term optimization of water use and simulation of water allocation. A case study in Bahia Do Rio Dos Sinos in Southern Brazil is presented. The framework couples an optimization model with quadratic programming model in GAMS with WEAP, a rain runoff simulation models that hosts the water supply infrastructure features and hydrologic conditions. Results allow (a) identification of trade offs between cost and reliability of different expansion paths and water use decisions and (b) evaluation of potential gains by reducing water system losses as a portfolio component. The latter is critical in several developing countries where water supply system losses are high and often neglected in favor of more system expansion. Results also highlight the potential of various water supply alternatives including, conservation, groundwater, and infrastructural enhancements over time. The framework proves its usefulness for planning its transferability to similarly urbanized systems.

  19. Water reabsorption capacity of the proximal convoluted tubule: a microperfusion study on rat kidney.

    PubMed Central

    Corman, B; Roinel, N; De Rouffignac, C

    1981-01-01

    1. The differences in the water reabsorption capacity observed from one proximal tubule to another were investigated in vivo by continuous microperfusion. 2. Two to seven loops were punctured along the same tubule. The [3H]inulin, 22Na, [14C]glucose, sodium, chloride and magnesium concentrations as well as the osmolality of the collected samples were studied as a function of the perfused length. 3. With Ringer bicarbonate solution perfused in Saclay Wistar rats, the water reabsorption capacity ranged from 0 to 3 nl . min-1 . mm-1 depending on the tubule. This reabsorption rate was closely correlated with the unidirectional reabsorption flux of sodium, and with the rise in tubular chloride and magnesium concentrations. 4. In Munich Wistar rats with glomeruli accessible at the kidney surface, tubule perfusion with a Ringer bicarbonate solution showed that the highest water reabsorption rates per mm of tubule were found for the perfusion sites closest to the glomerulus; water fluxes were also positively correlated with glucose transport. 5. In a second series of experiments on Saclay rats, perfusion of a Ringer solution containing a high chloride concentration (137 m-equiv/l.) was unable to increase the water reabsorption rate compared to the control perfusion; here again, water fluxes were positively correlated with glucose transport. PMID:7320874

  20. Differential absorption and Raman lidar for water vapor profile measurements - A review

    NASA Technical Reports Server (NTRS)

    Grant, William B.

    1991-01-01

    Differential absorption lidar and Raman lidar have been applied to the range-resolved measurements of water vapor density for more than 20 years. Results have been obtained using both lidar techniques that have led to improved understanding of water vapor distributions in the atmosphere. This paper reviews the theory of the measurements, including the sources of systematic and random error; the progress in lidar technology and techniques during that period, including a brief look at some of the lidar systems in development or proposed; and the steps being taken to improve such lidar systems.

  1. Moisture absorption characteristics of the Orbiter thermal protection system and methods used to prevent water ingestion

    NASA Technical Reports Server (NTRS)

    Schomburg, C.; Dotts, R. L.; Tillian, D. J.

    1983-01-01

    The Space Shuttle Orbiter's silica tile Thermal Protection System (TPS) is beset by the moisture absorption problems inherently associated with low density, highly porous insulation systems. Attention is presently given to the comparative success of methods for the minimization and/or prevention of water ingestion by the TPS tiles, covering the development of water-repellent agents and their tile application techniques, flight test program results, and materials improvements. The use of external films for rewaterproofing of the TPS tiles after each mission have demonstrated marginal to unacceptable performance. By contrast, a tile interior waterproofing agent has shown promise.

  2. Automated atomic absorption spectrometric determination of total arsenic in water and streambed materials

    USGS Publications Warehouse

    Fishman, M.

    1977-01-01

    An automated method to determine both inorganic and organic forms of arsenic In water, water-suspended mixtures, and streambed materials Is described. Organic arsenic-containing compounds are decomposed by either ultraviolet radiation or by suHurlc acid-potassium persulfate digestion. The arsenic liberated, with Inorganic arsenic originally present, is reduced to arsine with sodium borohydrlde. The arable Is stripped from the solution with the aid of nitrogen and Is then decomposed In a tube furnace heated to 800 ??C which Is placed in the optical path of an atomic absorption spectrometer. Thirty samples per hour can be analyzed to levels of 1 ??g arsenic per liter.

  3. Effects of Thinning Intensities on Soil Infiltration and Water Storage Capacity in a Chinese Pine-Oak Mixed Forest

    PubMed Central

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning): <60%, <15%, and <30%. It demonstrated that thinning operation with 30% intensity can substantially improve soil infiltration rate and water storage capacity of pine-oak mixed forest in Qinling Mountains. The soil initial infiltration rate, stable infiltration rate, and average infiltration rate in thinning 30% treatment were significantly increased by 21.1%, 104.6%, and 60.9%, compared with the control. The soil maximal water storage capacity and noncapillary water storage capacity in thinning 30% treatment were significantly improved by 20.1% and 34.3% in contrast to the control. The soil infiltration rate and water storage capacity were significantly higher in the surface layer (0~20 cm) than in the deep layers (20~40 cm and 40~60 cm). We found that the soil property was closely related to soil infiltration rate and water storage capacity. PMID:24883372

  4. Effects of thinning intensities on soil infiltration and water storage capacity in a Chinese pine-oak mixed forest.

    PubMed

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning): <60%, <15%, and <30%. It demonstrated that thinning operation with 30% intensity can substantially improve soil infiltration rate and water storage capacity of pine-oak mixed forest in Qinling Mountains. The soil initial infiltration rate, stable infiltration rate, and average infiltration rate in thinning 30% treatment were significantly increased by 21.1%, 104.6%, and 60.9%, compared with the control. The soil maximal water storage capacity and noncapillary water storage capacity in thinning 30% treatment were significantly improved by 20.1% and 34.3% in contrast to the control. The soil infiltration rate and water storage capacity were significantly higher in the surface layer (0~20 cm) than in the deep layers (20~40 cm and 40~60 cm). We found that the soil property was closely related to soil infiltration rate and water storage capacity.

  5. Impact of operating conditions on cooling capacity for sorption systems using water as refrigerant

    NASA Astrophysics Data System (ADS)

    Tremeac, Brice; Giraud, Florine; Vallon, Pierrick

    2017-02-01

    The implementation of compact heat exchanger in sorption systems is a key factor to allow the development of these systems. The aim of this paper is to develop a statistical model with a design of experiment (DOE) methodology and use dimensionless number to evaluate and understand the influence of the height of refrigerant liquid and secondary fluid inlet temperature on cooling capacity of a compact pate-type evaporator for sorption systems working near vacuum pressure. For this purpose, an experimental campaign was conducted on a small adsorption test bench using 13X/water as working couple. Cooling capacities from 640 to 2000 W were measured. The DOE is a Doelhert type with two parameters: the inlet secondary fluid temperature (from 10 to 21 °C) and the filing level of refrigerant in the evaporator (from 6 to 24 cm). Thanks to the exploitation of the mathematical model obtained, optimal points under different constraints were found. A maximum cooling capacity of 2021 +/-75 W in the entire experimental field was predicted for a secondary fluid inlet temperature of 25°C and a height of liquid level of 19.2 cm. Bond number and modified Jacob number per the ratio Psat/Ptriple were analyzed. The dimensionless numbers are correlated to the cooling capacity as a first step for designing compact plate-type evaporator for adsorption systems using water as refrigerant.

  6. Impact of the hydraulic capacity of plants on water and carbon fluxes in tropical South America

    NASA Astrophysics Data System (ADS)

    Lee, Jung-Eun; Boyce, Kevin

    2010-12-01

    Angiosperms (flowering plants) have higher transpirational capacities than any other plants. Here we use climate model simulation to test the hypothesis that the high transpirational capacity of angiosperms plays a unique role in the maintenance of tropical rainforest. Their elevated transpiration rates are shown to increase recycling of precipitation up to ˜300 mm/yr (˜20% of total precipitation) averaged over the whole of tropical South America and to increase the wet season duration over the Amazon basin. Transpiration triggers convection by increasing moisture in the boundary layer and thereby decreasing atmospheric stability. If the moisture content of the boundary layer is sufficient, a double Intertropical Convergence Zone (ITCZ) is generated in October around 60°W-50°W, as observed in present-day climate, and the eastern part of the Amazon basin becomes wet (˜200 mm/month of precipitation). This double ITCZ is lost, however, and the region becomes dry (<50 mm/month of precipitation) in the absence of full angiosperm transpiration. Although higher water use efficiency is usually associated with plants with lower transpiration rates, water use efficiency actually increases with higher hydraulic capacity in our simulations as a result of the higher humidity and, thus, lower vapor pressure gradient between the intercellular air space within the leaf and the external atmosphere. We speculate that the high transpirational capacity of angiosperms played a significant role in the expansion of tropical rain forest.

  7. Strong water absorption in the dayside emission spectrum of the planet HD 189733b.

    PubMed

    Grillmair, Carl J; Burrows, Adam; Charbonneau, David; Armus, Lee; Stauffer, John; Meadows, Victoria; van Cleve, Jeffrey; von Braun, Kaspar; Levine, Deborah

    2008-12-11

    Recent observations of the extrasolar planet HD 189733b did not reveal the presence of water in the emission spectrum of the planet. Yet models of such 'hot-Jupiter' planets predict an abundance of atmospheric water vapour. Validating and constraining these models is crucial to understanding the physics and chemistry of planetary atmospheres in extreme environments. Indications of the presence of water in the atmosphere of HD 189733b have recently been found in transmission spectra, where the planet's atmosphere selectively absorbs the light of the parent star, and in broadband photometry. Here we report the detection of strong water absorption in a high-signal-to-noise, mid-infrared emission spectrum of the planet itself. We find both a strong downturn in the flux ratio below 10 microm and discrete spectral features that are characteristic of strong absorption by water vapour. The differences between these and previous observations are significant and admit the possibility that predicted planetary-scale dynamical weather structures may alter the emission spectrum over time. Models that match the observed spectrum and the broadband photometry suggest that heat redistribution from the dayside to the nightside is weak. Reconciling this with the high nightside temperature will require a better understanding of atmospheric circulation or possible additional energy sources.

  8. In-Line Capacitance Sensor for Real-Time Water Absorption Measurements

    NASA Technical Reports Server (NTRS)

    Nurge, Mark A.; Perusich, Stephen A.

    2010-01-01

    A capacitance/dielectric sensor was designed, constructed, and used to measure in real time the in-situ water concentration in a desiccant water bed. Measurements were carried out with two experimental setups: (1) passing nitrogen through a humidity generator and allowing the gas stream to become saturated at a measured temperature and pressure, and (2) injecting water via a syringe pump into a nitrogen stream. Both water vapor generating devices were attached to a downstream vertically-mounted water capture bed filled with 19.5 g of Moisture Gone desiccant. The sensor consisted of two electrodes: (1) a 1/8" dia stainless steel rod placed in the middle of the bed and (2) the outer shell of the stainless steel bed concentric with the rod. All phases of the water capture process (background, heating, absorption, desorption, and cooling) were monitored with capacitance. The measured capacitance was found to vary linearly with the water content in the bed at frequencies above 100 kHz indicating dipolar motion dominated the signal; below this frequency, ionic motion caused nonlinearities in the water concentration/capacitance relationship. The desiccant exhibited a dielectric relaxation whose activation energy was lowered upon addition of water indicating either a less hindered rotational motion or crystal reorientation.

  9. Ultraviolet Absorption Spectrum of Malonaldehyde in Water Is Dominated by Solvent-Stabilized Conformations

    SciTech Connect

    Xu, Xuefei; Zheng, Jingjing; Truhlar, Donald G.

    2015-07-01

    Free energy calculations for eight enol isomers of malonaldehyde (MA) and simulation of the ultraviolet (UV) absorption spectrum in both the gas phase and water (pH = 3, where the molecule exists in neutral undeprotonated form) show that in water the two s-trans nonchelated enol conformers of MA become thermodynamically more stable than the internally hydrogen-bonded (“chelated enol”) conformer (CE). The pure CE conformer in water has a slightly red-shifted UV spectrum with respect to that in the gas phase, but the blue-shifted spectrum observed in water at pH 3 is dominated by solvent-stabilized conformations that have negligible populations in the gas phase. Density functional calculations with the solvation model based on density (SMD) and an ensemble-averaged vertical excitation model explain the experimental observations in detail.

  10. Ultraviolet Absorption Spectrum of Malonaldehyde in Water Is Dominated by Solvent-Stabilized Conformations.

    PubMed

    Xu, Xuefei; Zheng, Jingjing; Truhlar, Donald G

    2015-07-01

    Free energy calculations for eight enol isomers of malonaldehyde (MA) and simulation of the ultraviolet (UV) absorption spectrum in both the gas phase and water (pH = 3, where the molecule exists in neutral undeprotonated form) show that in water the two s-trans nonchelated enol conformers of MA become thermodynamically more stable than the internally hydrogen-bonded ("chelated enol") conformer (CE). The pure CE conformer in water has a slightly red-shifted UV spectrum with respect to that in the gas phase, but the blue-shifted spectrum observed in water at pH 3 is dominated by solvent-stabilized conformations that have negligible populations in the gas phase. Density functional calculations with the solvation model based on density (SMD) and an ensemble-averaged vertical excitation model explain the experimental observations in detail.

  11. Infrared absorption and Raman scattering spectra of water under pressure via first principles molecular dynamics.

    PubMed

    Ikeda, Takashi

    2014-07-28

    From both the polarized and depolarized Raman scattering spectra of supercritical water a peak located at around 1600 cm(-1), attributed normally to bending mode of water molecules, was experimentally observed to vanish, whereas the corresponding peak remains clearly visible in the measured infrared (IR) absorption spectrum. In this computational study a theoretical formulation for analyzing the IR and Raman spectra is developed via first principles molecular dynamics combined with the modern polarization theory. We demonstrate that the experimentally observed peculiar behavior of the IR and Raman spectra for water are well reproduced in our computational scheme. We discuss the origins of a feature observed at 1600 cm(-1) in Raman spectra of ambient water.

  12. Airborne differential absorption lidar system for measurements of atmospheric water vapor and aerosols.

    PubMed

    Higdon, N S; Browell, E V; Ponsardin, P; Grossmann, B E; Butler, C F; Chyba, T H; Mayo, M N; Allen, R J; Heuser, A W; Grant, W B; Ismail, S; Mayor, S D; Carter, A F

    1994-09-20

    An airborne differential absorption lidar (DIAL) system has been developed at the NASA Langley Research Center for remote measurements of atmospheric water vapor (H(2)O) and aerosols. A solid-state alexandrite laser with a 1-pm linewidth and > 99.85% spectral purity was used as the on-line transmitter. Solid-state avalanche photodiode detector technology has replaced photomultiplier tubes in the receiver system, providing an average increase by a factor of 1.5-2.5 in the signal-to-noise ratio of the H(2)O measurement. By incorporating advanced diagnostic and data-acquisition instrumentation into other subsystems, we achieved additional improvements in system operational reliability and measurement accuracy. Laboratory spectroscopic measurements of H(2)O absorption-line parameters were perfo med to reduce the uncertainties in our knowledge of the absorption cross sections. Line-center H(2)O absorption cross sections were determined, with errors of 3-6%, for more than 120 lines in the 720-nm region. Flight tests of the system were conducted during 1989-1991 on the NASA Wallops Flight Facility Electra aircraft, and extensive intercomparison measurements were performed with dew-point hygrometers and H(2)O radiosondes. The H(2)O distributions measured with the DIAL system differed by ≤ 10% from the profiles determined with the in situ probes in a variety of atmospheric conditions.

  13. Airborne differential absorption lidar system for measurements of atmospheric water vapor and aerosols

    NASA Technical Reports Server (NTRS)

    Carter, Arlen F.; Allen, Robert J.; Mayo, M. Neale; Butler, Carolyn F.; Grossman, Benoist E.; Ismail, Syed; Grant, William B.; Browell, Edward V.; Higdon, Noah S.; Mayor, Shane D.; Ponsardin, Patrick; Hueser, Alene W.

    1994-01-01

    An airborne differential absorption lidar (DIAL) system has been developed at the NASA Langley Research Center for remote measurements of atmospheric water vapor (H2O) and aerosols. A solid-state alexandrite laser with a 1-pm linewidth and greater than 99.85% spectral purity was used as the on-line transmitter. Solid-state avalanche photodiode detector technology has replaced photomultiplier tubes in the receiver system, providing an average increase by a factor of 1.5-2.5 in the signal-to-noise ratio of the H2O measurement. By incorporating advanced diagnostic and data-acquisition instrumentation into other subsystems, we achieved additional improvements in system operational reliability and measurement accuracy. Laboratory spectroscopic measurements of H2O absorption-line parameters were performed to reduce the uncertainties in our knowledge of the absorption cross sections. Line-center H2O absorption cross sections were determined, with errors of 3-6%, for more than 120 lines in the 720-nm region. Flight tests of the system were conducted during 1989-1991 on the NASA Wallops Flight Facility Electra aircraft, and extensive intercomparison measurements were performed with dew-point hygrometers and H2O radiosondes. The H2O distributions measured with the DIAL system differed by less than 10% from the profiles determined with the in situ probes in a variety of atmospheric conditions.

  14. Seasonal variability in the light absorption properties of western Arctic waters: Parameterization of the individual components of absorption for ocean color applications

    NASA Astrophysics Data System (ADS)

    Matsuoka, Atsushi; Hill, Victoria; Huot, Yannick; Babin, Marcel; Bricaud, Annick

    2011-02-01

    The light absorption properties of particulate and dissolved materials strongly influence the propagation of visible light in oceanic waters and therefore the accuracy of ocean color algorithms. While the general absorption properties of these materials have been reported for Arctic waters, their seasonal variability remains unknown. We investigated the light absorption coefficients of phytoplankton [aϕ(λ)], nonalgal particles [aNAP(λ)], and colored dissolved organic matter [aCDOM(λ)] in both coastal and oceanic waters of the western Arctic Ocean from spring to autumn. Values for the chlorophyll a-specific absorption coefficient of phytoplankton [a*ϕ(440)] declined significantly from the ice melt period in the early spring to the summer. Using high-performance liquid chromatography, we show that the decrease in a*ϕ(440) was due to a strong package effect that overwhelmed the influence of the pigment composition. A decrease in the aNAP(λ) values from spring and summer to autumn likely originated from a decrease in the concentration of phytoplanktonic detritus. The aCDOM(λ) near the surface decreased by 34% from spring to summer as a result of photobleaching by solar radiation. The colored dissolved organic matter (CDOM) absorption values then increased significantly during autumn, resulting from the cumulative injection of Alaskan Coastal Waters into the Arctic as well as CDOM generated in situ. Our results suggest that all of the absorption components are tightly linked to biogeochemical processes, and thus the seasonal variability in aϕ(λ), aNAP(λ), and aCDOM(λ) should be taken into account in bio-optical models.

  15. Optimization of industrial structure based on water environmental carrying capacity in Tieling City.

    PubMed

    Yue, Qiang; Hou, Limin; Wang, Tong; Wang, Liusuo; Zhu, Yue; Wang, Xiu; Cheng, Xilei

    2015-01-01

    A system dynamics optimization model of the industrial structure of Tieling City based on water environmental carrying capacity has been established. This system is divided into the following subsystems: water resources, economics, population, contaminants, and agriculture and husbandry. Three schemes were designed to simulate the model from 2011 to 2020, and these schemes were compared to obtain an optimal social and economic development model in Tieling City. Policy recommendations on industrial structure optimization based on the optimal solution provide scientific decision-making advice to develop a strong and sustainable economy in Tieling.

  16. Aggregating available soil water holding capacity data for crop yield models

    NASA Technical Reports Server (NTRS)

    Seubert, C. E.; Daughtry, C. S. T.; Holt, D. A.; Baumgardner, M. F.

    1984-01-01

    The total amount of water available to plants that is held against gravity in a soil is usually estimated as the amount present at -0.03 MPa average water potential minus the amount present at -1.5 MPa water potential. This value, designated available water-holding capacity (AWHC), is a very important soil characteristic that is strongly and positively correlated to the inherent productivity of soils. In various applications, including assessing soil moisture status over large areas, it is necessary to group soil types or series as to their productivity. Current methods to classify AWHC of soils consider only total capacity of soil profiles and thus may group together soils which differ greatly in AWHC as a function of depth in the profile. A general approach for evaluating quantitatively the multidimensional nature of AWHC in soils is described. Data for 902 soil profiles, representing 184 soil series, in Indiana were obtained from the Soil Characterization Laboratory at Purdue University. The AWHC for each of ten 150-mm layers in each soil was established, based on soil texture and parent material. A multivariate clustering procedure was used to classify each soil profile into one of 4, 8, or 12 classes based upon ten-dimensional AWHC values. The optimum number of classes depends on the range of AWHC in the population of oil profiles analyzed and on the sensitivity of a crop to differences in distribution of water within the soil profile.

  17. Water treatment capacity of forward osmosis systems utilizing power plant waste heat

    DOE PAGES

    Zhou, Xingshi; Gingerich, Daniel B.; Mauter, Meagan S.

    2015-06-11

    Forward osmosis (FO) has the potential to improve the energy efficiency of membrane-based water treatment by leveraging waste heat from steam electric power generation as the primary driving force for separation. In this study, we develop a comprehensive FO process model, consisting of membrane separation, heat recovery, and draw solute regeneration (DSR) models. We quantitatively characterize three alternative processes for DSR: distillation, steam stripping, and air stripping. We then construct a mathematical model of the distillation process for DSR that incorporates hydrodynamics, mass and heat transport resistances, and reaction kinetics, and we integrate this into a model for the fullmore » FO process. Finally, we utilize this FO process model to derive a first-order approximation of the water production capacity given the rejected heat quantity and quality available at U.S. electric power facilities. We find that the upper bound of FO water treatment capacity using low-grade heat sources at electric power facilities exceeds process water treatment demand for boiler water make-up and flue gas desulfurization wastewater systems.« less

  18. Water treatment capacity of forward osmosis systems utilizing power plant waste heat

    SciTech Connect

    Zhou, Xingshi; Gingerich, Daniel B.; Mauter, Meagan S.

    2015-06-11

    Forward osmosis (FO) has the potential to improve the energy efficiency of membrane-based water treatment by leveraging waste heat from steam electric power generation as the primary driving force for separation. In this study, we develop a comprehensive FO process model, consisting of membrane separation, heat recovery, and draw solute regeneration (DSR) models. We quantitatively characterize three alternative processes for DSR: distillation, steam stripping, and air stripping. We then construct a mathematical model of the distillation process for DSR that incorporates hydrodynamics, mass and heat transport resistances, and reaction kinetics, and we integrate this into a model for the full FO process. Finally, we utilize this FO process model to derive a first-order approximation of the water production capacity given the rejected heat quantity and quality available at U.S. electric power facilities. We find that the upper bound of FO water treatment capacity using low-grade heat sources at electric power facilities exceeds process water treatment demand for boiler water make-up and flue gas desulfurization wastewater systems.

  19. Application of multiobjective optimization to scheduling capacity expansion of urban water resource systems

    NASA Astrophysics Data System (ADS)

    Mortazavi-Naeini, Mohammad; Kuczera, George; Cui, Lijie

    2014-06-01

    Significant population increase in urban areas is likely to result in a deterioration of drought security and level of service provided by urban water resource systems. One way to cope with this is to optimally schedule the expansion of system resources. However, the high capital costs and environmental impacts associated with expanding or building major water infrastructure warrant the investigation of scheduling system operational options such as reservoir operating rules, demand reduction policies, and drought contingency plans, as a way of delaying or avoiding the expansion of water supply infrastructure. Traditionally, minimizing cost has been considered the primary objective in scheduling capacity expansion problems. In this paper, we consider some of the drawbacks of this approach. It is shown that there is no guarantee that the social burden of coping with drought emergencies is shared equitably across planning stages. In addition, it is shown that previous approaches do not adequately exploit the benefits of joint optimization of operational and infrastructure options and do not adequately address the need for the high level of drought security expected for urban systems. To address these shortcomings, a new multiobjective optimization approach to scheduling capacity expansion in an urban water resource system is presented and illustrated in a case study involving the bulk water supply system for Canberra. The results show that the multiobjective approach can address the temporal equity issue of sharing the burden of drought emergencies and that joint optimization of operational and infrastructure options can provide solutions superior to those just involving infrastructure options.

  20. [Simulation and prediction of water environmental carrying capacity in Liaoning Province based on system dynamics model].

    PubMed

    Wang, Jian; Li, Xue-liang; Li, Fa-yun; Bao, Hong-xu

    2009-09-01

    By the methods of system dynamics, a water environmental carrying capacity (WECC) model was constructed, and the dynamic trend of the WECC in Liaoning Province was simulated by using this model, in combining with analytical hierarchy process (AHP) and the vector norm method. It was predicted that under the conditions of maintaining present development schemes, the WECC in this province in 2000-2050 would be decreased year after year. Only increasing water resources supply while not implementing scientific and rational management of water environment could not improve the regional WECC, and the integration of searching for new and saving present water resources with controlling wastewater pollution and reducing sewage discharge would be the only effective way to improve the WECC and the coordinated development of economy, society, and environment in Liaoning.

  1. Structural features and water holding capacities of pressed potato fibre polysaccharides.

    PubMed

    Ramaswamy, Urmila R; Kabel, Mirjam A; Schols, Henk A; Gruppen, Harry

    2013-04-02

    Pressed potato fibre (PPF) has a high water holding capacity (WHC) affecting its processing as an animal feed. The aim of this study was to characterize cell wall polysaccharides (CWPs) in PPF and investigate their WHC. This was done via sequential extractions. Half of all CWPs were recovered in the hot buffer soluble solids extract as pectins (uronic acid and rhamnose) and galactans wherein most pectins (76%) from PPF were water soluble. Most likely, the network of CWPs is loosened during processing of potatoes. PPF showed a WHC of 7.4 expressed as the amount of water held per g of dry matter (mL/g). Reconstituting hot buffer soluble solids with buffer insoluble solids in water gave a WHC comparable to that of PPF. Removal of alkali soluble solids, which mainly comprised xyloglucans, lowered the WHC of the final residue. The results indicated that interactions between CWPs could affect the WHC of PPF.

  2. Accelerated Capacity Development in Water Resources Education: the experiences of the Ethiopian Institute of Water Resources

    NASA Astrophysics Data System (ADS)

    Alamirew, T.; Mekonnen, G.; Viglione, A.

    2012-04-01

    Ethiopia recently recognises that the water resources development is the major entry point in poverty alleviation and sustainable development. Water in Ethiopia plays a key role in the Water-Energy-Food-nexus. Over 98% of the electricity in the country is generated using hydropower and yet about 2000 MW has been developed. Out of the 3.5 Mha potentially irrigable land, only 0.25 Mha has been developed to date. Access to drinking water supply coverage is among the lowest in the world. One of the limiting factors in harnessing the resource base is the absence of water professionals to face the fast growing demand in education, research, development in the water sector. Recognising this, in collaboration with University of Connecticut of the United States, Addis Ababa University launched the Ethiopian Institute of Water Resources (EIWR) by enrolling 18 PhD and 24 MSc students. The program is unique in that much of the course instructors are coming from US and European Universities, but deliver courses together with Ethiopian collaborators. This is supposed to facilitate knowledge and experience transfer from the US/EU scientist to Ethiopian counterparts. The theses/dissertations are designed to focus on Ethiopia's immediate hydrological problems on selected basins, and will be coordinated by three advisors for each PhD - one from US/EU, one from Ethiopian Universities, and one water professional from the sector. We report here the lessons learned in setting up the EIWR institute and the education program.

  3. Chiral monolithic absorbent constructed by optically active helical-substituted polyacetylene and graphene oxide: preparation and chiral absorption capacity.

    PubMed

    Li, Weifei; Wang, Bo; Yang, Wantai; Deng, Jianping

    2015-02-01

    Chiral monolithic absorbent is successfully constructed for the first time by using optically active helical-substituted polyacetylene and graphene oxide (GO). The preparative strategy is facile and straightforward, in which chiral-substituted acetylene monomer (Ma), cross-linker (Mb), and alkynylated GO (Mc) undergo copolymerization to form the desired monolithic absorbent in quantitative yield. The resulting monoliths are characterized by circular dichroism, UV-vis absorption, scanning electron microscopy (SEM), FT-IR, Raman, energy-dispersive spectrometer (EDS), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), XPS, and thermogravimetric analysis (TGA) techniques. The polymer chains derived from Ma form chiral helical structures and thus provide optical activity to the monoliths, while GO sheets contribute to the formation of porous structures. The porous structure enables the monolithic absorbents to demonstrate a large swelling ratio in organic solvents, and more remarkably, the helical polymer chains provide optical activity and further enantio-differentiating absorption ability. The present study establishes an efficient and versatile methodology for preparing novel functional materials, in particular monolithic chiral materials based on substituted polyacetylene and GO.

  4. Bathymetric surveys and area/capacity tables of water-supply reservoirs for the city of Cameron, Missouri, July 2013

    USGS Publications Warehouse

    Huizinga, Richard J.

    2014-01-01

    Years of sediment accumulation and dry conditions in recent years have led to the decline of water levels and capacities for many water-supply reservoirs in Missouri, and have caused renewed interest in modernizing outdated area/capacity tables for these reservoirs. The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, surveyed the bathymetry of the four water-supply reservoirs used by the city of Cameron, Missouri, in July 2013. The data were used to provide water managers with area/capacity tables and bathymetric maps of the reservoirs at the time of the surveys.

  5. Changes on image texture features of breakfast flakes cereals during water absorption.

    PubMed

    Medina, Wenceslao T; Quevedo, Roberto A; Aguilera, José M

    2013-02-01

    Normally breakfast cereal flakes are consumed by pouring them into a bowl and covering them with fresh or cold milk. During this process the liquid uptake causes changes in the surface and internal matrix of breakfast cereals that influence texture and integrity. Some breakfast cereal as flakes have a translucent structure that could provide information about the solid matrix and air cells and how they change during liquid absorption. The objective of the study was to assess the image texture changes of corn flakes and frosted flakes during water absorption at 5, 15 and 25 °C, employing 11 image feature textures extracted from grey-level co-occurrence matrix and grey-level run length matrix (at three directions) and to relate the fractal dimension (FD) of images with rupture force (RF) reduction during soaking of both flakes at 5 °C. The most relevant result from principal component analysis calculated with a matrix of 54 (soaking times) × 22 (texture features), shows that it was possible to distinguish an isolated group consisting of different soaking times at the same water temperature in each breakfast cereal flakes evaluated, corroborating that superficial liquid imbibition is important during the liquid absorption process when flakes are soaked. Furthermore, standardized FD could be related to RF in the period when samples tend to search for an equilibrium state.

  6. Correlation analysis of hyperspectral absorption features with the water status of coast live oak leaves

    NASA Astrophysics Data System (ADS)

    Pu, Ruiliang; Ge, Shaokui; Kelly, Nina M.; Gong, Peng

    2002-01-01

    A total of 139 reflectance spectra (between 350 and 2500 nm) from coast live oak (Quercus Agrifolia) leaves were measured in the laboratory with a spectrometer FieldSpec½Pro FR. Correlation analysis was conducted between absorption features, three-band ratio indices derived from the spectra and corresponding relative water content (RWC, %) of oak leaves. The experimental results indicate that there exist linear relationships between the RWC of oak leaves and absorption feature parameters: wavelength position (WAVE), absorption feature depth (DEP), width (WID) and the multiplication of DEP and WID (AREA) at the 975 nm, 1200 nm and 1750 nm positions and two three-band ratio indices: RATIO975 and RATIO1200, derived at 975 nm and 1200 nm. AREA has a higher and more stable correlation with RWC compared to other features. It is worthy of noting that the two three-band ratio indices, RATIO975 and RATIO1200, may have potential application in assessing water status in vegetation.

  7. Temperature sensitivity of differential absorption lidar measurements of water vapor in the 720-nm region

    NASA Technical Reports Server (NTRS)

    Browell, Edward V.; Ismail, Syed; Grossmann, Benoist E.

    1991-01-01

    Recently measured properties of water vapor (H2O) absorption lines have been used in calculations to evalute the temperature sensitivity of differential absorption lidar (Dial) H2O measurements. This paper estimates the temperature sensitivity of H2O lines in the 717-733-nm region for both H2O mixing ratio and number density measurements, and discusses the influence of the H2O line ground state energies E-double-prime, the H2O absorption linewidths, the linewidth temperature dependence parameter, and the atmospheric temperature and pressure variations with altitude and location on the temperature sensitivity calculations. Line parameters and temperature sensitivity calculations for 67 H2O lines in the 720-nm band are given which can be directly used in field experiments. Water vapor lines with E-double-prime values in the 100-300/cm range were found to be optimum for Dial measurements of H2O number densities, while E-double-prime values in the 250-500/cm range were found to be optimum for H2O mixing ratio measurements.

  8. Surface arsenic speciation of a drinking-water treatment residual using X-ray absorption spectroscopy.

    PubMed

    Makris, Konstantinos C; Sarkar, Dibyendu; Parsons, Jason G; Datta, Rupali; Gardea-Torresdey, Jorge L

    2007-07-15

    Drinking-water treatment residuals (WTRs) present a low-cost geosorbent for As-contaminated waters and soils. Previous work has demonstrated the high affinity of WTRs for As, but data pertaining to the stability of sorbed As is missing. Sorption/desorption and X-ray absorption spectroscopy (XAS), both XANES (X-ray absorption near edge structure) and EXAFS (extended X-ray absorption fine structure) studies, were combined to determine the stability of As sorbed by an Fe-based WTR. Arsenic(V) and As(III) sorption kinetics were biphasic in nature, sorbing >90% of the initial added As (15,000 mg kg(-1)) after 48 h of reaction. Subsequent desorption experiments with a high P load (7500 mg kg(-1)) showed negligible As desorption for both As species, approximately <3.5% of sorbed As; the small amount of desorbed As was attributed to the abundance of sorption sites. XANES data showed that sorption kinetics for either As(III) or As(V) initially added to solution had no effect on the sorbed As oxidation state. EXAFS spectroscopy suggested that As added either as As(III) or as As(V) formed inner-sphere mononuclear, bidentate complexes, suggesting the stability of the sorbed As, which was further corroborated by the minimum As desorption from the Fe-WTR.

  9. Atmospheric Pre-Corrected Differential Absorption Techniques to Retrieve Columnar Water Vapor: Theory and Simulations

    NASA Technical Reports Server (NTRS)

    Borel, Christoph C.; Schlaepfer, Daniel

    1996-01-01

    Two different approaches exist to retrieve columnar water vapor from imaging spectrometer data: (1) Differential absorption techniques based on: (a) Narrow-Wide (N/W) ratio between overlapping spectrally wide and narrow channels; (b) Continuum Interpolated Band Ratio (CIBR) between a measurement channel and the weighted sum of two reference channels. (2) Non-linear fitting techniques which are based on spectral radiative transfer calculations. The advantage of the first approach is computational speed and of the second, improved retrieval accuracy. Our goal was to improve the accuracy of the first technique using physics based on radiative transfer. Using a modified version of the Duntley equation, we derived an "Atmospheric Pre-corrected Differential Absorption" (APDA) technique and described an iterative scheme to retrieve water vapor on a pixel-by-pixel basis. Next we compared both, the CIBR and the APDA using the Duntley equation for MODTRAN3 computed irradiances, transmissions and path radiance (using the DISORT option). This simulation showed that the CIBR is very sensitive to reflectance effects and that the APDA performs much better. An extensive data set was created with the radiative transfer code 6S over 379 different ground reflectance spectra. The calculated relative water vapor error was reduced significantly for the APDA. The APDA technique had about 8% (vs. over 35% for the CIBR) of the 379 spectra with a relative water vapor error of greater than +5%. The APDA has been applied to 1991 and 1995 AVIRIS scenes which visually demonstrate the improvement over the CIBR technique.

  10. Diode laser-based standoff absorption measurement of water film thickness in retro-reflection

    NASA Astrophysics Data System (ADS)

    Pan, R.; Brocksieper, C.; Jeffries, J. B.; Dreier, T.; Schulz, C.

    2016-09-01

    A dual-wavelength diode laser-based absorption sensor for standoff point measurements of water film thickness on an opaque surface is presented. The sensor consists of a diode laser source, a foil as backscattering target, and off-axis paraboloids for collecting the fraction of the laser radiation transmitted through the liquid layer via retro-reflection. Laser wavelengths in the near infrared at 1412 and 1353 nm are used where the temperature dependence of the liquid water absorption cross section is known. The lasers are fiber coupled and the detection of the retro-reflected light was accomplished through a multimode fiber and a single photodiode using time-division multiplexing. The water film thickness at a given temperature was determined from measured transmittance ratios at the two laser wavelengths. The sensor concept was first validated with measurement using a temperature-controlled calibration cell providing liquid layers of variable and known thickness between 100 and 1000 µm. Subsequently, the sensor was demonstrated successfully during recording the time-varying thickness of evaporating water films at fixed temperatures. The film thickness was recorded as a function of time at three temperatures down to 50 µm.

  11. Selection of the optimal combination of water vapor absorption lines for detection of temperature in combustion zones of mixing supersonic gas flows by diode laser absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Mironenko, V. R.; Kuritsyn, Yu. A.; Bolshov, M. A.; Liger, V. V.

    2016-12-01

    Determination of a gas medium temperature by diode laser absorption spectrometry (DLAS) is based on the measurement of integral intensities of the absorption lines of a test molecule (generally water vapor molecule). In case of local thermodynamic equilibrium temperature is inferred from the ratio of the integral intensities of two lines with different low energy levels. For the total gas pressure above 1 atm the absorption lines are broadened and one cannot find isolated well resolved water vapor absorption lines within relatively narrow spectral interval of fast diode laser (DL) tuning range (about 3 cm-1). For diagnostics of a gas object in the case of high temperature and pressure DLAS technique can be realized with two diode lasers working in different spectral regions with strong absorption lines. In such situation the criteria of the optimal line selection differs significantly from the case of narrow lines. These criteria are discussed in our work. The software for selection the optimal spectral regions using the HITRAN-2012 and HITEMP data bases is developed. The program selects spectral regions of DL tuning, minimizing the error of temperature determination δT/T, basing on the attainable experimental error of line intensity measurement δS. Two combinations of optimal spectral regions were selected - (1.392 & 1.343 μm) and (1.392 & 1.339 μm). Different algorithms of experimental data processing are discussed.

  12. Performance characteristics of single effect lithium bromide/ water absorption chiller for small data centers

    NASA Astrophysics Data System (ADS)

    Mysore, Abhishek Arun Babu

    A medium data center consists of servers performing operations such as file sharing, collaboration and email. There are a large number of small and medium data centers across the world which consume more energy and are less efficient when compared to large data center facilities of companies such as GOOGLE, APPLE and FACEBOOK. Such companies are making their data center facilities more environmental friendly by employing renewable energy solutions such as wind and solar to power the data center or in data center cooling. This not only reduces the carbon footprint significantly but also decreases the costs incurred over a period of time. Cooling of data center play a vital role in proper functioning of the servers. It is found that cooling consumes about 50% of the total power consumed by the data center. Traditional method of cooling includes the use of mechanical compression chillers which consume lot of power and is not desirable. In order to eliminate the use of mechanical compressor chillers renewable energy resources such as solar and wind should be employed. One such technology is solar thermal cooling by means of absorption chiller which is powered by solar energy. The absorption chiller unit can be coupled with either flat plate or evacuated tube collectors in order to achieve the required inlet temperature for the generator of the absorption chiller unit. In this study a modular data center is considered having a cooling load requirement of 23kw. The performance characteristics of a single stage Lithium Bromide/ water refrigeration is presented in this study considering the cooling load of 23kw. Performance characteristics of each of the 4 heat exchangers within the unit is discussed which helps in customizing the unit according to the users' specific needs. This analysis helps in studying the importance of different properties such as the effect of inlet temperatures of hot water for generator, inlet temperatures of cooling water for absorber and

  13. Time-resolved x-ray absorption spectroscopy with a water window high-harmonic source

    NASA Astrophysics Data System (ADS)

    Pertot, Yoann; Schmidt, Cédric; Matthews, Mary; Chauvet, Adrien; Huppert, Martin; Svoboda, Vit; von Conta, Aaron; Tehlar, Andres; Baykusheva, Denitsa; Wolf, Jean-Pierre; Wörner, Hans Jakob

    2017-01-01

    Time-resolved x-ray absorption spectroscopy (TR-XAS) has so far practically been limited to large-scale facilities, to subpicosecond temporal resolution, and to the condensed phase. We report the realization of TR-XAS with a temporal resolution in the low femtosecond range by developing a tabletop high-harmonic source reaching up to 350 electron volts, thus partially covering the spectral region of 280 to 530 electron volts, where water is transmissive. We used this source to follow previously unexamined light-induced chemical reactions in the lowest electronic states of isolated CF4+ and SF6+ molecules in the gas phase. By probing element-specific core-to-valence transitions at the carbon K-edge or the sulfur L-edges, we characterized their reaction paths and observed the effect of symmetry breaking through the splitting of absorption bands and Rydberg-valence mixing induced by the geometry changes.

  14. Unsteady absorption of sulfur dioxide by an atmospheric water droplet with internal circulation

    NASA Astrophysics Data System (ADS)

    Chen, Wei-Hsin

    Unsteady absorption characteristics of sulfur dioxide by an atmospheric water droplet in motion are predicted numerically and analyzed theoretically to recognize the physical mass transport processes inside an aerosol droplet, which is frequently encountered in the atmosphere. Considering the absorption of sulfur dioxide by a droplet in cloud or fog with various velocities, three different Reynolds numbers, viz., Reg=0.643, 1.287, and 12.87 are studied and compared with each other. The results indicate that for the Reynolds number of 0.643, sulfur dioxide always penetrates toward the droplet centerline throughout the entire absorption period. This is due to the mass transfer dominated by diffusion along the radial direction. In contrast, when the Reynolds number is 12.87, the strength of the vortex motion inside the droplet is strong enough. It results in that, most of the time the concentration contours parallel the streamlines and the lowest SO 2 concentration is located at the vortex center. As a consequence, the diffusion distance is reduced by a factor of three and the absorption time for the droplet reaching the saturated state is shortened in a significant way. With regard to an intermediate Reynolds number such as 1.287, a two-stage mass transfer process can be clearly identified. In the first stage, it is dominated by one-dimensional diffusion, in which over 50% sulfur dioxide is absorbed before the saturated state is reached. In the second stage, the vortex motion mainly controls the mass transfer. However, the contour core is inconsistent with the vortex center. This is because the characteristic time of mass diffusion is in a comparable state with that of droplet internal circulation. The present study elucidates that the strength of a droplet's internal motion plays a vital role in determining SO 2 absorption process.

  15. Fractional water allocation and reservoir capacity sharing concepts: An adaptation for the Komati Basin

    NASA Astrophysics Data System (ADS)

    Dlamini, Enoch M.; Dhlamini, Sidney; Mthimkhulu, Sindy

    This paper presents an adaptation of fractional water allocation and reservoir capacity sharing (FWARCS) concepts for application in the Komati Basin, a river system shared between South Africa, Swaziland and Mozambique. Many traditional methods for allocating water are based on volume-per-unit-time allocation that is supplied at some level of assurance and managed using priority-based reservoir and river system operating rules, as well as on the “use it or lose it” principle, which is considered exclusive by water users as it leaves them out of the management of their water allocations. In the Komati Basin, these traditional methods of water allocation led to frequent conflicts among users and with water managers. However, the introduction of the modified FWARCS, which assigns available water in the system to water users according to the proportions of their water entitlements and allows water to be banked in reservoirs, appears to be a solution to some of these problems. This method allows water users to decide when and how much of that entitlement they may use. Since the implementation of the modified FWARCS technique in the Komati Basin in 2002, the regulation, transparency and efficiency of operating the system improved and subsequently the number of disputes over water has declined. South Africa improved from an overuse of 8.2 Mm 3 in 2002/03 water year to realize a saving of 29.5 Mm 3 in 2005/06. Similarly, Swaziland improved from an overuse of 3.9 Mm 3 in 2002/03 to achieve a saving of 14.6 Mm 3 in 2005/06. Users have recognised and embraced the transparency and flexibility of the modified FWARCS. They choose, as the need and opportunity arise, when and how much water they utilise, whether to “bank” and/or “trade” the water they save subject to the conditions of their entitlements. The implementation of the modified FWARCS was also made successful by the existence of proper institutional structures, appropriate decision support tools, good water

  16. Phase Transfer-Catalyzed Fast CO2 Absorption by MgO-Based Absorbents with High Cycling Capacity

    SciTech Connect

    Zhang, Keling; Li, Xiaohong S.; Li, Weizhen; Rohatgi, Aashish; Duan, Yuhua; Singh, Prabhakar; Li, Liyu; King, David L.

    2014-06-01

    CO2 capture from pre-combustion syngas in the temperature range of 250-400°C is highly desirable from an energy efficiency perspective. Thermodynamically, MgO is a promising material for CO2 capture, but the gas-solid reaction to produce MgCO3 is kinetically slow due to high lattice energy. We report here fast CO2 absorption over a solid MgO-molten nitrate/nitrite aggregate through phase transfer catalysis, in which the molten phase serves as both a catalyst and reaction medium. Reaction with CO2 at the gas-solid-liquid triple phase boundary results in formation of MgCO3 with significant reaction rate and a high conversion of MgO. This methodology is also applicable to other alkaline earth oxides, inspiring the design of absorbents which require activation of the bulk material.

  17. Effects of rainfall seasonality and soil moisture capacity on mean annual water balance for Australian catchments

    USGS Publications Warehouse

    Potter, N.J.; Zhang, L.; Milly, P.C.D.; McMahon, T.A.; Jakeman, A.J.

    2005-01-01

    An important factor controlling catchment-scale water balance is the seasonal variation of climate. The aim of this study is to investigate the effect of the seasonal distributions of water and energy, and their interactions with the soil moisture store, on mean annual water balance in Australia at catchment scales using a stochastic model of soil moisture balance with seasonally varying forcing. The rainfall regime at 262 catchments around Australia was modeled as a Poisson process with the mean storm arrival rate and the mean storm depth varying throughout the year as cosine curves with annual periods. The soil moisture dynamics were represented by use of a single, finite water store having infinite infiltration capacity, and the potential evapotranspiration rate was modeled as an annual cosine curve. The mean annual water budget was calculated numerically using a Monte Carlo simulation. The model predicted that for a given level of climatic aridity the ratio of mean annual evapotranspiration to rainfall was larger where the potential evapotranspiration and rainfall were in phase, that is, in summer-dominant rainfall catchments, than where they were out of phase. The observed mean annual evapotranspiration ratios have opposite results. As a result, estimates of mean annual evapotranspiration from the model compared poorly with observational data. Because the inclusion of seasonally varying forcing alone was not sufficient to explain variability in the mean annual water balance, other catchment properties may play a role. Further analysis showed that the water balance was highly sensitive to the catchment-scale soil moisture capacity. Calibrations of this parameter indicated that infiltration-excess runoff might be an important process, especially for the summer-dominant rainfall catchments; most similar studies have shown that modeling of infiltration-excess runoff is not required at the mean annual timescale. Copyright 2005 by the American Geophysical Union.

  18. Building leadership capacity to drive sustainable water management: the evaluation of a customised program.

    PubMed

    Taylor, A C

    2010-01-01

    This paper describes a customised, six-month, leadership development program (LDP) that was designed for emerging leaders in the Australian water industry who were promoting sustainable urban water management (SUWM). It also presents results from an evaluation of the program's benefits, costs and overall 'return on investment' (ROI). The program was designed to help build emergent leadership capacity in the water industry, given strong evidence that this form of leadership plays an important role in advancing SUWM. It involved '360-degree feedback' processes, training, individual leadership development plans, and coaching sessions. Its design was informed by a review of the literature, and its content was informed by local empirical research involving effective SUWM leaders. The evaluation used a seven-tier assessment framework that examined different dimensions of the program's performance using source and methodological triangulation. The results indicate that such LDPs can produce a range of positive outcomes, such as promoting desired leadership behaviours and generating a positive ROI estimate. Specifically, the program's estimated ROI was approximately 190% after only one year. The primary conclusion is that evidence-based LDPs which are highly customised for specific types of leaders in the water industry represent a promising type of intervention to build forms of leadership capacity which are needed to successfully promote SUWM.

  19. Performance of Generator of Absorption Refrigerating Machine Powered by Hot Water

    NASA Astrophysics Data System (ADS)

    Kunugi, Yoshifumi; Usui, Sanpei; Ouchi, Tomihisa; Fukuda, Tamio

    For 70 kW generator of absorption refrigerating machine powered by the hot water, lifted liquid rate of the bubble lift pump has a maximum value at some vapor flow rate of refrigerant and hot water inlet temperature. This is in agreement with results of small size bubble lift pump. Maximum lifted liquid rate G0 is correlated by the equation G0 = 5, 000σ1.5, where σ is the degree of submergence. In this case, diameter of pump tube was 41.6mm, and length of it were 1,300 and 1,500mm. The range of hot water inlet temperature was 78 - 100°C. Multitube heat flux of first generator is about two times that of second generator at the same superheat.

  20. Modeling of water absorption induced cracks in resin-based composite supported ceramic layer structures.

    PubMed

    Huang, Min; Thompson, V P; Rekow, E D; Soboyejo, W O

    2008-01-01

    Cracking patterns in the top ceramic layers of the modeled dental multilayers with polymer foundation are observed when they are immersed in water. This article developed a model to understand this cracking mechanism. When water diffuses into the polymer foundation of dental restorations, the foundation will expand; as a result, the stress will build up in the top ceramic layer because of the bending and stretching. A finite element model based on this mechanism is built to predict the stress build-up and the slow crack growth in the top ceramic layers during the water absorption. Our simulations show that the stress build-up by this mechanism is high enough to cause the cracking in the top ceramic layers and the cracking patterns predicted by our model are well consistent with those observed in experiments on glass/epoxy/polymer multilayers. The model is then used to discuss the life prediction of different dental ceramics.

  1. Determination of soluble aluminium concentration in alkaline humic water using atomic absorption spectrophotometry.

    PubMed

    Nguyen, K L; Lewis, D M; Jolly, M; Robinson, J

    2004-11-01

    The steps of the standard method to determine soluble aluminium concentration are filtering, followed by acidifying, then analysing with the atomic absorption spectrophotometer (AAS). When applied to alkaline humic water, acidification gives rise to the formation of humic acid as a brown particulate matter. Of the total soluble aluminium in the original water, 49-61% forms complexes with the particulate humic acid upon acidification. Although the AAS is capable of detecting the binding aluminium, the particulate nature of humic acid easily induces inaccurate readings as a result of the non-uniform distribution of the particulate matter. A more precise analysis of soluble aluminium concentration of alkaline humic water is shown to be achievable in basicified solutions instead. Basicified solutions keep humic acid in the soluble form; hence maintain the homogeneity of the sample.

  2. Kenaf/recycled Jute Natural Fibers Unsaturated Polyester Composites: Water Absorption/dimensional Stability and Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Osman, Ekhlas A.; Vakhguelt, Anatoli; Sbarski, Igor; Mutasher, Saad A.

    2012-03-01

    Effects of water absorption on the flexural properties of kenaf-unsaturated polyester composites and kenaf/recycled jute-unsaturated polyester composites were investigated. In the hybrid composites, the total fiber content was fixed to 20 wt%. In this 20 wt%, the addition of jute fiber varied from 0 to 75%, with increment of 25%. The result demonstrates the water absorption and the thickness swelling increased with increase in immersion time. Effects of water absorption on flexural properties of kenaf fiber composites can be reduced significantly with incorporation of recycled jute in composites formulation. The process of absorption of water was found to approach Fickian diffusion behavior for both kenaf composites and hybrid composites.

  3. Method 200.12 - Determination of Trace Elements in Marine Waters by StabilizedTemperature Graphite Furnace Atomic Absorption

    EPA Science Inventory

    This method provides procedures for the determination of total recoverable elements by graphite furnace atomic absorption (GFAA) in marine waters, including estuarine, ocean and brines with salinities of up to 35 ppt.

  4. The relationship between the glass transition temperature and water vapor absorption by poly(vinylpyrrolidone)

    PubMed

    Oksanen, C A; Zografi, G

    1990-06-01

    Water associated with amorphous solids is known to affect significantly the physical and chemical properties of dosage form ingredients. An analysis of water vapor absorption isotherms of poly(vinylpyrrolidone) measured in this and other laboratories, over the range -40 to 60 degrees C, along with the measurement of the glass transition temperature of poly(vinylpyrrolidone) as a function of water content is reported. It is observed that the amount of water vapor absorbed at a particular relative humidity increases with decreasing temperature, along with a significant change in the shape of the isotherm. It is also shown that at any temperature, along with a significant change in the shape of the isotherm. It is also shown that at any temperature the state of the solid changes from a highly viscous glass to a much less viscous rubber in the region where absorbed water appears to enter into a "solvent-like" state. Further, the apparent "tightly bound" state, observed at low relative humidities, appears to exist when the polymer enters into a very viscous glassy state. It is concluded that the apparent states of water and polymer are interrelated in a dynamic manner and, therefore, that they cannot be uncoupled by simple thermodynamic analyses based only on a water-binding model.

  5. Surface Water Storage Capacity of Twenty Tree Species in Davis, California.

    PubMed

    Xiao, Qingfu; McPherson, E Gregory

    2016-01-01

    Urban forestry is an important green infrastructure strategy because healthy trees can intercept rainfall, reducing stormwater runoff and pollutant loading. Surface saturation storage capacity, defined as the thin film of water that must wet tree surfaces before flow begins, is the most important variable influencing rainfall interception processes. Surface storage capacity is known to vary widely among tree species, but it is little studied. This research measured surface storage capacities of 20 urban tree species in a rainfall simulator. The measurement system included a rainfall simulator, digital balance, digital camera, and computer. Eight samples were randomly collected from each tree species. Twelve rainfall intensities (3.5-139.5 mm h) were simulated. Leaf-on and leaf-off simulations were conducted for deciduous species. Stem and foliar surface areas were estimated using an image analysis method. Results indicated that surface storage capacities varied threefold among tree species, 0.59 mm for crape myrtle ( L.) and 1.81 mm for blue spruce ( Engelm.). The mean value across all species was 0.86 mm (0.11 mm SD). To illustrate application of the storage values, interception was simulated and compared across species for a 40-yr period with different rainfall intensities and durations. By quantifying the potential for different tree species to intercept rainfall under a variety of meteorological conditions, this study provides new knowledge that is fundamental to validating the cost-effectiveness of urban forestry as a green infrastructure strategy and designing functional plantings.

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

    PubMed Central

    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. PMID:23990758

  7. RF Path and Absorption Loss Estimation for Underwater Wireless Sensor Networks in Different Water Environments

    PubMed Central

    Qureshi, Umair Mujtaba; Shaikh, Faisal Karim; Aziz, Zuneera; Shah, Syed M. Zafi S.; Sheikh, Adil A.; Felemban, Emad; Qaisar, Saad Bin

    2016-01-01

    Underwater Wireless Sensor Network (UWSN) communication at high frequencies is extremely challenging. The intricacies presented by the underwater environment are far more compared to the terrestrial environment. The prime reason for such intricacies are the physical characteristics of the underwater environment that have a big impact on electromagnetic (EM) signals. Acoustics signals are by far the most preferred choice for underwater wireless communication. Because high frequency signals have the luxury of large bandwidth (BW) at shorter distances, high frequency EM signals cannot penetrate and propagate deep in underwater environments. The EM properties of water tend to resist their propagation and cause severe attenuation. Accordingly, there are two questions that need to be addressed for underwater environment, first what happens when high frequency EM signals operating at 2.4 GHz are used for communication, and second which factors affect the most to high frequency EM signals. To answer these questions, we present real-time experiments conducted at 2.4 GHz in terrestrial and underwater (fresh water) environments. The obtained results helped in studying the physical characteristics (i.e., EM properties, propagation and absorption loss) of underwater environments. It is observed that high frequency EM signals can propagate in fresh water at a shallow depth only and can be considered for a specific class of applications such as water sports. Furthermore, path loss, velocity of propagation, absorption loss and the rate of signal loss in different underwater environments are also calculated and presented in order to understand why EM signals cannot propagate in sea water and oceanic water environments. An optimal solk6ution for underwater communication in terms of coverage distance, bandwidth and nature of communication is presented, along with possible underwater applications of UWSNs at 2.4 GHz. PMID:27322263

  8. Nanosheet-structured boron nitride spheres with a versatile adsorption capacity for water cleaning.

    PubMed

    Liu, Fei; Yu, Jie; Ji, Xixi; Qian, Muqi

    2015-01-28

    Here, we report the synthesis of nanosheet-structured boron nitride spheres (NSBNSs) by a catalyzing thermal evaporation method from solid B powders. The NSBNSs consist of radially oriented ultrathin nanosheets with the sheet edges oriented on the surface. Formation of this unique structure occurs only at a certain reaction temperature. The diameter from 4 μm to 700 nm and the nanosheet thickness from 9.1 to 3.1 nm of the NSBNSs can be well-controlled by appropriately changing the mass ratio of boron powders and catalyst. The NSBNSs possess versatile adsorption capacity, exhibiting excellent adsorption performance for oil, dyes, and heavy metal ions from water. The oil uptake reaches 7.8 times its own weight. The adsorption capacities for malachite green and methylene blue are 324 and 233 mg/g, while those for Cu(2+), Pb(2+), and Cd(2+) are 678.7, 536.7, and 107.0 mg/g, respectively. The adsorption capacities of the NSBNSs for Cu(2+) and Pb(2+) are higher or much higher than those of the adsorbents reported previously. These results demonstrate the great potential of NSBNSs for water treatment and cleaning.

  9. Near-infrared studies of glucose and sucrose in aqueous solutions: water displacement effect and red shift in water absorption from water-solute interaction.

    PubMed

    Jung, Youngeui; Hwang, Jungseek

    2013-02-01

    We used near infrared spectroscopy to obtain concentration dependent glucose absorption spectra in aqueous solutions in the near-infrared range (3800-7500 cm(-1)). Here we introduce a new method to obtain reliable glucose absorption bands from aqueous glucose solutions without measuring the water displacement coefficients of glucose separately. Additionally, we were able to extract the water displacement coefficients of glucose, and this may offer a new general method using spectroscopy techniques applicable to other water-soluble materials. We also observed red shifts in the absorption bands of water in the hydration shell around solute molecules, which comes from the contribution of the interacting water molecules around the glucose molecules in solutions. The intensity of the red shift gets larger as the concentration increases, which indicates that as the concentration increases more water molecules are involved in the interaction. However, the red shift in frequency does not seem to depend significantly on the concentration. We also performed the same measurements and analysis with sucrose instead of glucose as solute and compared.

  10. Propagation of ultrashort laser pulses in water: linear absorption and onset of nonlinear spectral transformation.

    PubMed

    Sokolov, Alexei V; Naveira, Lucas M; Poudel, Milan P; Strohaber, James; Trendafilova, Cynthia S; Buck, William C; Wang, Jieyu; Strycker, Benjamin D; Wang, Chao; Schuessler, Hans; Kolomenskii, Alexandre; Kattawar, George W

    2010-01-20

    We study propagation of short laser pulses through water and use a spectral hole filling technique to essentially perform a sensitive balanced comparison of absorption coefficients for pulses of different duration. This study is motivated by an alleged violation of the Bouguer-Lambert-Beer law at low light intensities, where the pulse propagation is expected to be linear, and by a possible observation of femtosecond optical precursors in water. We find that at low intensities, absorption of laser light is determined solely by its spectrum and does not directly depend on the pulse duration, in agreement with our earlier work and in contradiction to some work of others. However, as the laser fluence is increased, interaction of light with water becomes nonlinear, causing energy exchange among the pulse's spectral components and resulting in peak-intensity dependent (and therefore pulse-duration dependent) transmission. For 30 fs pulses at 800 nm center wavelength, we determine the onset of nonlinear propagation effects to occur at a peak value of about 0.12 mJ/cm(2) of input laser energy fluence.

  11. High-resolution atmospheric water vapor measurements with a scanning differential absorption lidar

    NASA Astrophysics Data System (ADS)

    Späth, F.; Behrendt, A.; Muppa, S. K.; Metzendorf, S.; Riede, A.; Wulfmeyer, V.

    2014-11-01

    The scanning differential absorption lidar (DIAL) of the University of Hohenheim (UHOH) is presented. The UHOH DIAL is equipped with an injection-seeded frequency-stabilized high-power Ti:sapphire laser operated at 818 nm with a repetition rate of 250 Hz. A scanning transceiver unit with a 80 cm primary mirror receives the atmospheric backscatter signals. The system is capable of water vapor measurements with temporal resolutions of a few seconds and a range resolution between 30 and 300 m at daytime. It allows to investigate surface-vegetation-atmosphere exchange processes with high resolution. In this paper, we present the design of the instrument and illustrate its performance with recent water vapor measurements taken in Stuttgart-Hohenheim and in the frame of the HD(CP)2 Observational Prototype Experiment (HOPE). HOPE was located near research center Jülich, in western Germany, in spring 2013 as part of the project "High Definition of Clouds and Precipitation for advancing Climate Prediction" (HD(CP)2). Scanning measurements reveal the 3-dimensional structures of the water vapor field. The influence of uncertainties within the calculation of the absorption cross-section at wavelengths around 818 nm for the WV retrieval is discussed. Radiosonde intercomparisons show a very small bias between the instruments of only (-0.04 ± 0.11) g m-3 or (-1.0 ± 2.3) % in the height range of 0.5 to 3 km.

  12. Assessment of absorption potential of poorly water-soluble drugs by using the dissolution/permeation system.

    PubMed

    Kataoka, Makoto; Yano, Koji; Hamatsu, Yoriko; Masaoka, Yoshie; Sakuma, Shinji; Yamashita, Shinji

    2013-11-01

    This study aims to assess the absorption potential of oral absorption of poorly water-soluble drugs by using the dissolution/permeation system (D/P system). The D/P system can be used to perform analysis of drug permeation under dissolution process and can predict the fraction of absorbed dose in humans. When celecoxib at 1/100 of a clinical dose was applied to the D/P system, percentage of dose dissolved and permeated significantly decreased with an increase in the applied amount, resulting in the oral absorption being predicted to be 22-55%. Whereas similar dissolution and permeation profiles of montelukast sodium were observed, estimated absorption (69-85%) was slightly affected. Zafirlukast absorption (33-36%) was not significantly affected by the dose, although zafirlukast did not show complete dissolution. The relationship between clinical dose and predicted oral absorption of drugs corresponded well to clinical observations. The limiting step of the oral absorption of celecoxib and montelukast sodium was solubility, while that of zafirlukast was dissolution rate. However, due to high permeability of montelukast, oral absorption was not affected by dose. Therefore, the D/P system is a useful tool to assess the absorption potential of poorly water-soluble drugs for oral use.

  13. Pectins from the albedo of immature lemon fruitlets have high water binding capacity.

    PubMed

    Schröder, Roswitha; Clark, Christopher J; Sharrock, Keith; Hallett, Ian C; MacRae, Elspeth A

    2004-04-01

    The white part of citrus peel, the albedo, has a special role in water relations of both fruit and leaves from early on in fruit development. In times of drought, this tissue acts as a water reservoir for juice sacs, seeds and leaves. When water was injected into the albedo, free water was undetectable using magnetic resonance imaging. Microscopy showed tightly packed cells with little intercellular space, and thick cell walls. Cell wall material comprised 21% of the fresh albedo weight, and contained 26.1% galacturonic acid, the main constituent of pectin. From this, we postulated that pectin of the cell wall was responsible for the high water-binding capacity of the immature lemon albedo. Cell wall material was extracted using mild procedures that keep polymers intact, and four pectic fractions were recovered. Of these fractions, the SDS and chelator-soluble fractions showed viscosities ten and twenty times higher than laboratory-grade citrus pectin or the other albedo-derived pectins. The yield of these two pectins represented 28% of the cell walls and 62% of the galacturonic acid content of immature lemon albedo. We concluded that, from viscosity and abundance, these types of pectin account for the high water-binding capacity of this tissue. Compositional analyses showed that the two highly viscous pectic fractions differ in galacturonic acid content, degree of branching and length of side chains from the less viscous albedo-derived pectins. The most striking feature of these highly viscous pectins, however, was their high molecular weight distribution compared to the other pectic fractions.

  14. Simulation model of a single-stage lithium bromide-water absorption cooling unit

    NASA Technical Reports Server (NTRS)

    Miao, D.

    1978-01-01

    A computer model of a LiBr-H2O single-stage absorption machine was developed. The model, utilizing a given set of design data such as water-flow rates and inlet or outlet temperatures of these flow rates but without knowing the interior characteristics of the machine (heat transfer rates and surface areas), can be used to predict or simulate off-design performance. Results from 130 off-design cases for a given commercial machine agree with the published data within 2 percent.

  15. Femtosecond supercontinuum generation in water in the vicinity of absorption bands.

    PubMed

    Dharmadhikari, J A; Steinmeyer, G; Gopakumar, G; Mathur, D; Dharmadhikari, A K

    2016-08-01

    We show that it is possible to overcome the perceived limitations caused by absorption bands in water so as to generate supercontinuum (SC) spectra in the anomalous dispersion regime that extend well beyond 2000 nm wavelength. By choosing a pump wavelength within a few hundred nanometers above the zero-dispersion wavelength of 1048 nm, initial spectral broadening extends into the normal dispersion regime and, in turn, the SC process in the visible strongly benefits from phase-matching and matching group velocities between dispersive radiation and light in the anomalous dispersion regime. Some of the SC spectra are shown to encompass two and a half octaves.

  16. Multiplexed detection of xylene and trichloroethylene in water by photonic crystal absorption spectroscopy.

    PubMed

    Lai, Wei-Cheng; Chakravarty, Swapnajit; Zou, Yi; Chen, Ray T

    2013-10-01

    We experimentally demonstrate simultaneous selective detection of xylene and trichloroethylene (TCE) using multiplexed photonic crystal waveguides (PCWs) by near-infrared optical absorption spectroscopy on a chip. Based on the slow light effect of photonic crystal structure, the sensitivity of our device is enhanced to 1 ppb (v/v) for xylene and 10 ppb (v/v) for TCE in water. Multiplexing is enabled by multimode interference power splitters and Y-combiners that integrate multiple PCWs on a silicon chip in a silicon-on-insulator platform.

  17. A DRM for steady water absorption from different types of periodic channels

    NASA Astrophysics Data System (ADS)

    Solekhudin, I.

    2017-01-01

    In this paper, problems involving steady infiltration from a homogeneous soil with water absorption by plant roots are studied. Different geometries of periodic channels are considered. The governing equation of the problems is a Richards equation. This equation may not be solved analytically. Hence, a numerical method is needed. To do so, the equation is transformed into a modified Helmholtz equation using a set of transformations involving Kirchhoff transformation, dimensionless variables and an exponential transformation. The modified Helmholtz equation is then solved numerically using a Dual Reciprocity Method (DRM) with a predictor-corrector scheme. Results obtained from channels with different geometries are presented.

  18. Complexing capacity of natural waters carrying a great amount of suspended matter.

    PubMed

    Minaberry, Yanina S; Gordillo, Gabriel J

    2007-11-01

    The cadmium binding properties of waters of the superior section of the Rio de la Plata estuarine were determined over a three-year period. Samples were collected at different hydrodynamic conditions. The complexing capacity was determined by square wave anodic stripping voltammetry (SWASV). Titration curve data were analyzed using a multivariable regression. Suspended particulate matter (SPM) was identified by XR diffraction and FTIR. These analyses showed that SPM principal components are clays (illite, montmorillonite and chlorite). The study was applied to the untreated, filtered and centrifuged fractions of each sample at the pH of the natural waters and at pH 1. The results show that the contribution of dissolved organic matter to the complexing capacity is negligible when compared with SPM. At natural pH, the complexing capacity of filtered and untreated fractions can be described by considering two kinds of binding sites. The associated conditional binding constants are independent of the concentration of suspended matter. Their average logarithms are ca. 6.5 and ca. 4.4. The total concentration of binding sites (S(T)) is in microM range, which is about three orders of magnitude higher than that reported for most of the studied estuaries. This difference is explained on the basis of the great amount of SPM. Hydrodynamic conditions produce variations in the concentration and composition of the SPM. At pH 1 samples still exhibit an important complexing capacity with only one binding site with log K(cond) ca. 5.4. These differences could be attributed to superficial modifications that take place at very low pH.

  19. Influence of Water Activated by Far infrared Porous Ceramics on Nitrogen Absorption in the Pig Feed.

    PubMed

    Meng, Junping; Liu, Jie; Liang, Jinsheng; Zhang, Hongchen; Ding, Yan

    2016-04-01

    Under modern and, intensive feeding livestock and poultry density has increased, and brought a deterioration of the farm environment. The livestock and their excrement generate harmful gases such as ammonia, etc. which restricted the sustainable development and improvement of production efficiency of animal husbandry. In this paper, a new kind of far infrared porous ceramics was prepared to activate, the animal drinking water. The activated water and common water were then supplied to pigs, and the fresh pig feces of experimental group and:control group were collected on a regular basis. The residual protein content in feces was tested by Kjeldahl nitrogen method to study the influence law of the porous ceramics on absorbing nitrogen element in animal feces. The results showed that compared with the control group, the protein content in the experimental group decreased on average by 39.2%. The activated drinking water was conducive to the absorption of nitrogen in pig feed. The clusters of water molecules became smaller under the action of the porous ceramics. Hence, they were easy to pass through the water protein channel on the cell membrane for speeding up the metabolism.

  20. [Determination of rubidium and cesium in chloride type oilfield water by flame atomic absorption spectrometry].

    PubMed

    Ye, Xiu-Shen; Zhang, Shan-Ying; Li, Hai-Jun; Li, Wu; Wu, Zhi-Jian

    2009-03-01

    Flame atomic absorption spectrometry (FAAS) was applied to the determination of rubidium and cesium in chloride type oilfield water by considering the interferences of the coexistent K+, Na+, Ca2+, and Mg2+ ions, Standard curve method and standard addition method were compared in the determination of rubidium and cesium in the simulated oilfield water and the real oilfield water from the Nanyishan region in Qaidam Basin. Although rubidium and cesium have similar physical-chemical properties, they present different characters during their analyses using the FAAS technique. When the standard addition method was used for the determination of rubidium and cesium in the simulated oilfield water, the results of rubidium were very poor, whereas the results of cesium were satisfactory. When the standard curve method was used for the determination of rubidium and cesium in the simulated oilfield water, the results of both rubidium and cesium were satisfactory within the linear ranges of the standard curves. For the real oilfield water, standard addition method is also only applicable for the determination of cesium with a recovery ranging from 90% to 110%. While standard curve method is applicable for the determination of both rubidium and cesium with a recovery ranging from 90% to 110%.

  1. Communication: Hydrogen bonding interactions in water-alcohol mixtures from X-ray absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Lam, Royce K.; Smith, Jacob W.; Saykally, Richard J.

    2016-05-01

    While methanol and ethanol are macroscopically miscible with water, their mixtures exhibit negative excess entropies of mixing. Despite considerable effort in both experiment and theory, there remains significant disagreement regarding the origin of this effect. Different models for the liquid mixture structure have been proposed to address this behavior, including the enhancement of the water hydrogen bonding network around the alcohol hydrophobic groups and microscopic immiscibility or clustering. We have investigated mixtures of methanol, ethanol, and isopropanol with water by liquid microjet X-ray absorption spectroscopy on the oxygen K-edge, an atom-specific probe providing details of both inter- and intra-molecular structure. The measured spectra evidence a significant enhancement of hydrogen bonding originating from the methanol and ethanol hydroxyl groups upon the addition of water. These additional hydrogen bonding interactions would strengthen the liquid-liquid interactions, resulting in additional ordering in the liquid structures and leading to a reduction in entropy and a negative enthalpy of mixing, consistent with existing thermodynamic data. In contrast, the spectra of the isopropanol-water mixtures exhibit an increase in the number of broken alcohol hydrogen bonds for mixtures containing up to 0.5 water mole fraction, an observation consistent with existing enthalpy of mixing data, suggesting that the measured negative excess entropy is a result of clustering or micro-immiscibility.

  2. A new device for acquiring ground truth on the absorption of light by turbid waters

    NASA Technical Reports Server (NTRS)

    Klemas, V. (Principal Investigator); Srna, R.; Treasure, W.

    1974-01-01

    The author has identified the following significant results. A new device, called a Spectral Attenuation Board, has been designed and tested, which enables ERTS-1 sea truth collection teams to monitor the attenuation depths of three colors continuously, as the board is being towed behind a boat. The device consists of a 1.2 x 1.2 meter flat board held below the surface of the water at a fixed angle to the surface of the water. A camera mounted above the water takes photographs of the board. The resulting film image is analyzed by a micro-densitometer trace along the descending portion of the board. This yields information on the rate of attenuation of light penetrating the water column and the Secchi depth. Red and green stripes were painted on the white board to approximate band 4 and band 5 of the ERTS MSS so that information on the rate of light absorption by the water column of light in these regions of the visible spectrum could be concurrently measured. It was found that information from a red, green, and white stripe may serve to fingerprint the composition of the water mass. A number of these devices, when automated, could also be distributed over a large region to provide a cheap method of obtaining valuable satellite ground truth data at present time intervals.

  3. Body centered cubic magnesium niobium hydride with facile room temperature absorption and four weight percent reversible capacity.

    PubMed

    Tan, XueHai; Wang, Liya; Holt, Chris M B; Zahiri, Beniamin; Eikerling, Michael H; Mitlin, David

    2012-08-21

    We have synthesized a new metastable metal hydride with promising hydrogen storage properties. Body centered cubic (bcc) magnesium niobium hydride (Mg(0.75)Nb(0.25))H(2) possesses 4.5 wt% hydrogen gravimetric density, with 4 wt% being reversible. Volumetric hydrogen absorption measurements yield an enthalpy of hydride formation of -53 kJ mol(-1) H(2), which indicates a significant thermodynamic destabilization relative to the baseline -77 kJ mol(-1) H(2) for rutile MgH(2). The hydrogenation cycling kinetics are remarkable. At room temperature and 1 bar hydrogen it takes 30 minutes to absorb a 1.5 μm thick film at sorption cycle 1, and 1 minute at cycle 5. Reversible desorption is achieved in about 60 minutes at 175 °C. Using ab initio calculations we have examined the thermodynamic stability of metallic alloys with hexagonal close packed (hcp) versus bcc crystal structure. Moreover we have analyzed the formation energies of the alloy hydrides that are bcc, rutile or fluorite.

  4. Spectral absorption properties of colored dissolved organic matter (CDOM) and total suspended matter (TSM) of inland waters

    NASA Astrophysics Data System (ADS)

    Song, Kaishan; Liu, Dianwei; Li, Lin; Wang, Zongming; Wang, Yuandong; Jiang, Guangjia

    2010-08-01

    Spectral absorption properties of total suspended matter (TSM) and colored dissolved organic matter (CDOM) are important for the use of the bio-optical model to estimate water quality parameters. This study aims to investigate the variation in the absorption coefficients of TSM and CDOM of inland waters. A total of 92 water samples were collected from Shitoukoumen Reservoir and Songhua Lake in Northeast China, analyzed for TSM and Chl-a, and measured for the absorption coefficient of TSM, CDOM and total pigments using a laboratory spectrophotometer. The absorption coefficient of TSM has been decomposed for phytoplankton and inorganic sediments. The results show that for Shitoukoumen Reservoir, CDOM has strong absorptions with shallow absorption slopes (i.e., the coefficient S in a(λ)=a(λ0)exp[-S(λ- λ0)]) and large absorption at 355 nm; and for Songhua Lake, CDOM follows similar spectral absorption curves but less variation in the S value. The results also show TSM has the average absorption coefficient 5.7 m-1 at 440 nm and 0.93 m-1 at 675 nm, and their concentration is well correlated to TSM with R2 larger than 0.85 at 440 nm over both Songhu Lake and Shitoukoumen Reservoir. In summer, CDOM was mainly terrigenous and had a high proportion of humic acid derived from the decomposition of phytoplankton and there were no obvious difference of S value. The results indicate that inorganic sediments contributed much more absorption than phytoplankton pigments in Shitoukoumen Reservoir than that in Songhua Lake, and there is strong association of TSM concentration to absorption coefficient at 440 nm.

  5. Aerosol absorption measurement at SWIR with water vapor interference using a differential photoacoustic spectrometer.

    PubMed

    Zhu, Wenyue; Liu, Qiang; Wu, Yi

    2015-09-07

    Atmospheric aerosol plays an important role in atmospheric radiation balance through absorbing and scattering the solar radiation, which changes local weather and global climate. Accurate measurement is highly requested to estimate the radiative effects and climate effects of atmospheric aerosol. Photoacoustic spectroscopy (PAS) technique, which observes the aerosols on their natural suspended state and is insensitive to light scattering, is commonly recognized as one of the best candidates to measure the optical absorption coefficient (OAC) of aerosols. In the present work, a method of measuring aerosol OAC at the wavelength where could also be absorbed by water vapor was proposed and corresponding measurements of the absorption properties of the atmospheric aerosol at the short wave infrared (SWIR, 1342 nm) wavelength were carried out. The spectrometer was made up of two high performance homemade photoacoustic cells. To improve the sensitivity, several methods were presented to control the noise derived from gas flow and vibration from the sampling pump. Calibration of the OAC and properties of the system were also studied in detail. Using the established PAS instrument, measurement of the optical absorption properties of the atmospheric aerosol were carried out in laboratory and field environment.

  6. Nonlinear absorption dynamics using field-induced surface hopping: zinc porphyrin in water.

    PubMed

    Röhr, Merle I S; Petersen, Jens; Wohlgemuth, Matthias; Bonačić-Koutecký, Vlasta; Mitrić, Roland

    2013-05-10

    We wish to present the application of our field-induced surface-hopping (FISH) method to simulate nonlinear absorption dynamics induced by strong nonresonant laser fields. We provide a systematic comparison of the FISH approach with exact quantum dynamics simulations on a multistate model system and demonstrate that FISH allows for accurate simulations of nonlinear excitation processes including multiphoton electronic transitions. In particular, two different approaches for simulating two-photon transitions are compared. The first approach is essentially exact and involves the solution of the time-dependent Schrödinger equation in an extended manifold of excited states, while in the second one only transiently populated nonessential states are replaced by an effective quadratic coupling term, and dynamics is performed in a considerably smaller manifold of states. We illustrate the applicability of our method to complex molecular systems by simulating the linear and nonlinear laser-driven dynamics in zinc (Zn) porphyrin in the gas phase and in water. For this purpose, the FISH approach is connected with the quantum mechanical-molecular mechanical approach (QM/MM) which is generally applicable to large classes of complex systems. Our findings that multiphoton absorption and dynamics increase the population of higher excited states of Zn porphyrin in the nonlinear regime, in particular in solution, provides a means for manipulating excited-state properties, such as transient absorption dynamics and electronic relaxation.

  7. Effect of water on the carbon dioxide absorption by 1-alkyl-3-methylimidazolium acetate ionic liquids.

    PubMed

    Stevanovic, Stéphane; Podgoršek, Ajda; Pádua, Agilio A H; Costa Gomes, Margarida F

    2012-12-13

    The absorption of carbon dioxide by the pure ionic liquids 1-ethyl-3-methylimidazolium acetate ([C(1)C(2)Im][OAc]) and 1-butyl-3-methylimidazolium acetate ([C(1)C(4)Im][OAc]) was studied experimentally from 303 to 343 K. As expected, the mole fraction of absorbed carbon dioxide is high (0.16 at 303 K and 5.5 kPa and 0.19 at 303 and 9.6 KPa for [C(1)C(2)Im][OAc] and [C(1)C(4)Im][OAc], respectively), does not obey Henry's law, and is compatible with the chemisorption of the gas by the liquid. Evidence of a chemical reaction between the gas and the liquid was found both by NMR and by molecular simulation. In the presence of water, the properties of the liquid absorber significantly change, especially the viscosity that decreases by as much as 25% (to 78 mPa s) and 30% (to 262 mPa s) in the presence of 0.2 mol fraction of water for [C(1)C(2)Im][OAc] and [C(1)C(2)Im][OAc] at 303 K, respectively. The absorption of carbon dioxide decreases when the water concentration increases: a decrease of 83% in CO(2) absorption is found for [C(1)C(4)Im][OAc] with 0.6 mol fraction of water at 303 K. It is proved in this work, by combining experimental data with molecular simulation, that the presence of water not only renders the chemical reaction between the gas and the ionic liquid less favorable but also lowers the (physical) solubility of the gas as it competes by the same solvation sites of the ionic liquid. The lowering of the viscosity of the liquid absorbent largely compensates these apparent drawbacks and the mixtures of [C(1)C(2)Im][OAc] and [C(1)C(2)Im][OAc] with water seem promising to be used for carbon dioxide capture.

  8. Hydrogen-rich water enhances cadmium tolerance in Chinese cabbage by reducing cadmium uptake and increasing antioxidant capacities.

    PubMed

    Wu, Qi; Su, Nana; Cai, Jiangtao; Shen, Zhenguo; Cui, Jin

    2015-03-01

    The aim of the present paper was to understand the specific mechanism of hydrogen-rich water (HRW) in alleviating cadmium (Cd) toxicity in Chinese cabbage (Brassica campestris spp. chinensis L.). Our results showed that the addition of 50% saturation HRW significantly alleviated the Cd toxic symptoms, including the improvement of both root elongation and seedling growth inhibition. These responses were consistent with a significant decrease of Cd accumulation in roots and shoots, which was further confirmed by the histochemical staining. Molecular evidence illustrated that Cd-induced up-regulations of IRT1 and Nramp1 genes, responsible for Cd absorption, were blocked by HRW. By contrast, Cd-induced up-regulation of the HMA3 gene, which regulates Cd sequestration into the root vacuoles, was substantially strengthened by HRW. Furthermore, compared with those in Cd stress alone, the expressions of HMA2 and HMA4, which function in the transportation of Cd to xylem, were repressed by co-treatment with HRW. HRW enhanced the activities of antioxidant enzymes, including superoxide dismutase, guaiacol peroxidase, catalase and ascorbate peroxidase. These results were further confirmed by the alleviation of oxidative damage, as indicated by the decrease of thiobarbituric acid reactive substances (TBARS) and reactive oxygen species (ROS) production. Taken together, these results suggest that the improvement of Cd tolerance by HRW was associated with reduced Cd uptake and increased antioxidant defense capacities. Therefore, the application of HRW may be a promising strategy to improve Cd tolerance of Chinese cabbage.

  9. Evaluation of alkaline electrolyzed water to replace traditional phosphate enhancement solutions: Effects on water holding capacity, tenderness, and sensory characteristics.

    PubMed

    Rigdon, Macc; Hung, Yen-Con; Stelzleni, Alexander M

    2017-01-01

    Sixty-four pork loins were randomly assigned to one of four treatments to evaluate the use of alkaline electrolyzed reduced water as a replacement for traditional enhancement solutions. Treatments included: alkaline electrolyzed reduced water (EOH; pH≈11.5), EOH plus 2.5% potassium-lactate (EOK), industry standard (IS; 0.35% sodium tri-polyphosphate, 0.14% sodium chloride, 2.5% potassium-lactate), and no enhancement (CON). After enhancement (targeting 110%) and rest period, chops were cut (2.54-cm) to test treatment effects on water holding capacity, Warner-Bratzler shear force (WBSF), and sensory attributes. Despite its alkaline nature EOH chops exuded more water (P<0.05) than EOK, IS, or CON chops. Control chops were similar (P>0.05) to EOK, however CON and EOK both lost more moisture (P<0.05) than IS. The use of alkaline electrolyzed reduced water did not improve WBSF or sensory characteristics compared to IS treated chops. As a stand-alone enhancement solution alkaline electrolyzed reduced water was not a suitable replacement for industry standard solutions.

  10. Antioxidant capacity, phenolic constituents and toxicity of hot water extract from red maple buds.

    PubMed

    Meda, Naamwin R; Poubelle, Patrice E; Stevanovic, Tatjana

    2017-03-11

    The present study reports, for the first time, the results of the antioxidant capacity and the phenolic composition of a hot water extract from red maple buds (RMB), as well as its safety. In this regard and comparatively to antioxidant standards, this extract exhibits a significant antiradical capacity when tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and anion superoxide trapping assays. High-resolution mass spectrometric (HRMS) and Nuclear Magnetic Resonance (NMR) analyses permitted to determine for the first time, in red maple species, cyanidin-3-O-glucoside, quercetin-3-O-galactoside, quercetin-3-O-arabinoside and quercetin. Also, the quantification of individual phenolics by high-performance liquid chromatography (HPLC) method revealed that ginnalin A at 117.0 mg/g is the major compound of RMB hot water extract. Finally, using flow cytometry evaluation, the extract of RMB was determined to have no toxicity neither to cause significant modification of apoptosis process, up to concentration of 100 μg / mL, on human peripheral blood neutrophils. These results allow anticipating various fields of application of RMB water extract. This article is protected by copyright. All rights reserved.

  11. Estimating a Global Hydrological Carrying Capacity Using GRACE Observed Water Stress

    NASA Astrophysics Data System (ADS)

    An, K.; Reager, J. T.; Famiglietti, J. S.

    2013-12-01

    Global population is expected to reach 9 billion people by the year 2050, causing increased demands for water and potential threats to human security. This study attempts to frame the overpopulation problem through a hydrological resources lens by hypothesizing that observed groundwater trends should be directly attributed to human water consumption. This study analyzes the relationships between available blue water, population, and cropland area on a global scale. Using satellite data from NASA's Gravity Recovery and Climate Experiment (GRACE) along with land surface model data from the Global Land Data Assimilation System (GLDAS), a global groundwater depletion trend is isolated, the validity of which has been verified in many regional studies. By using the inherent distributions of these relationships, we estimate the regional populations that have exceeded their local hydrological carrying capacity. Globally, these populations sum to ~3.5 billion people that are living in presently water-stressed or potentially water-scarce regions, and we estimate total cropland is exceeding a sustainable threshold by about 80 million km^2. Key study areas such as the North China Plain, northwest India, and Mexico City were qualitatively chosen for further analysis of regional water resources and policies, based on our distributions of water stress. These case studies are used to verify the groundwater level changes seen in the GRACE trend . Tfor the many populous, arid regions of the world that have already begun to experience the strains of high water demand.he many populous, arid regions of the world have already begun to experience the strains of high water demand. It will take a global cooperative effort of improving domestic and agricultural use efficiency, and summoning a political will to prioritize environmental issues to adapt to a thirstier planet. Global Groundwater Depletion Trend (Mar 2003-Dec 2011)

  12. Heat capacity anomaly in a self-aggregating system: Triblock copolymer 17R4 in water

    NASA Astrophysics Data System (ADS)

    Dumancas, Lorenzo V.; Simpson, David E.; Jacobs, D. T.

    2015-05-01

    The reverse Pluronic, triblock copolymer 17R4 is formed from poly(propylene oxide) (PPO) and poly(ethylene oxide) (PEO): PPO14 - PEO24 - PPO14, where the number of monomers in each block is denoted by the subscripts. In water, 17R4 has a micellization line marking the transition from a unimer network to self-aggregated spherical micelles which is quite near a cloud point curve above which the system separates into copolymer-rich and copolymer-poor liquid phases. The phase separation has an Ising-like, lower consolute critical point with a well-determined critical temperature and composition. We have measured the heat capacity as a function of temperature using an adiabatic calorimeter for three compositions: (1) the critical composition where the anomaly at the critical point is analyzed, (2) a composition much less than the critical composition with a much smaller spike when the cloud point curve is crossed, and (3) a composition near where the micellization line intersects the cloud point curve that only shows micellization. For the critical composition, the heat capacity anomaly very near the critical point is observed for the first time in a Pluronic/water system and is described well as a second-order phase transition resulting from the copolymer-water interaction. For all compositions, the onset of micellization is clear, but the formation of micelles occurs over a broad range of temperatures and never becomes complete because micelles form differently in each phase above the cloud point curve. The integrated heat capacity gives an enthalpy that is smaller than the standard state enthalpy of micellization given by a van't Hoff plot, a typical result for Pluronic systems.

  13. Direct relationship between osmotic and ionic conforming behavior and tissue water regulatory capacity in echinoids.

    PubMed

    Santos, Ivonete A; Castellano, Giovanna C; Freire, Carolina A

    2013-03-01

    Echinoderms are considered marine osmoconforming invertebrates. However, many are intertidal or live next to estuaries, tolerating salinity changes and showing extracellular gradients to dilute seawater. Three species of echinoids - Lytechinus variegatus, which can occur next to estuarine areas, the rocky intertidal Echinometra lucunter, and the mostly subtidal Arbacia lixula - were submitted to a protocol of stepwise (rate of 2-3 psu/h) dilution, down to 15 psu, or concentration, up to 45 psu, of control seawater (35 psu). Coelomic fluid samples were obtained every hour. The seawater dilution experiment lasted 8h, while the seawater concentration experiment lasted 6h. Significant gradients (40-90% above value in 15 psu seawater) for osmolality, sodium, magnesium, and potassium were shown by L. variegatus and E. lucunter. A. lixula showed the smallest gradients, displaying the strongest conforming behavior. The esophagus of the three species was challenged in vitro with 20 and 50% osmotic shocks (hypo- and hyperosmotic). A. lixula, the most "conforming" species, showed the highest capacity to avoid swelling of its tissues upon the -50% hyposmotic shock, and was also the species less affected by salinity changes concerning the observation of spines and ambulacral feet movement in the whole-animal experiments. Thus, the most conforming species (A. lixula) displayed the highest capacity to regulate tissue water/volume, and was also the most euryhaline among the three studied species. In addition, tissues from all three species swelled much more than they shrank under osmotic shocks of same magnitude. This distinct trend to gain water, despite the capacity to hold some gradients upon seawater dilution, helps to explain why echinoderms cannot be fully estuarine, or ever enter fresh water.

  14. A study on flexural and water absorption of surface modified rice husk flour/E-glass/polypropylene hybrid composite

    NASA Astrophysics Data System (ADS)

    Rassiah, K.; Sin, T. W.; Ismail, M. Z.

    2016-10-01

    This work is to study the effects of rice husk (RH)/E-Glass (EG)/polypropylene (PP) hybrid composites in terms of flexural and water absorption properties. The tests conducted are the flexural test and also the water absorption test using two types of water: distilled and sea water. The hybrid composites are prepared with various ratios of fibre weight fractions and the rice husk is treated using 2% Sodium Hydroxide (NaOH) to improve interaction and adhesion between the non-polar matrix and the polar lignocellulosic fibres. It was found that the content of rice husk/E-Glass fillers affected the structural integrity and flexural properties of hybrid composites. In addition, a higher ratio of rice husk contributes to higher water absorption in the hybrid composites.

  15. X-ray absorption signatures of the molecular environment in water and ice.

    PubMed

    Chen, Wei; Wu, Xifan; Car, Roberto

    2010-07-02

    The x-ray absorption spectra of water and ice are calculated with a many-body approach for electron-hole excitations. The experimental features, including the effects of temperature change in the liquid, are reproduced from configurations generated by ab initio molecular dynamics. The spectral difference between the solid and the liquid is due to two major short-range order effects. One, due to breaking of hydrogen bonds, enhances the pre-edge intensity in the liquid. The other, due to a nonbonded molecular fraction in the first coordination shell, affects the main spectral edge in the conversion of ice to water. This effect may not involve hydrogen bond breaking as shown by experiment in high-density amorphous ice.

  16. Differential Absorption Measurements of Atmospheric Water Vapor with a Coherent Lidar at 2050.532 nm

    NASA Technical Reports Server (NTRS)

    Koch, Grady J.; Dharamsi, Amin; Davis, Richard E.; Petros, Mulugeta; McCarthy, John C.

    1999-01-01

    Wind and water vapor are two major factors driving the Earth's atmospheric circulation, and direct measurement of these factors is needed for better understanding of basic atmospheric science, weather forecasting, and climate studies. Coherent lidar has proved to be a valuable tool for Doppler profiling of wind fields, and differential absorption lidar (DIAL) has shown its effectiveness in profiling water vapor. These two lidar techniques are generally considered distinctly different, but this paper explores an experimental combination of the Doppler and DIAL techniques for measuring both wind and water vapor with an eye-safe wavelength based on a solid-state laser material. Researchers have analyzed and demonstrated coherent DIAL water vapor measurements at 10 micrometers wavelength based on CO2 lasers. The hope of the research presented here is that the 2 gm wavelength in a holmium or thulium-based laser may offer smaller packaging and more rugged operation that the CO2-based approach. Researchers have extensively modeled 2 um coherent lasers for water vapor profiling, but no published demonstration is known. Studies have also been made, and results published on the Doppler portion, of a Nd:YAG-based coherent DIAL operating at 1.12 micrometers. Eye-safety of the 1.12 micrometer wavelength may be a concern, whereas the longer 2 micrometer and 10 micrometer systems allow a high level of eyesafety.

  17. Changes of color and water-absorption of Hungarian porous limestone due to biomineralization

    NASA Astrophysics Data System (ADS)

    Juhász, P.; Kopecskó, K.

    2013-12-01

    Bacteria induced calcium carbonate precipitation nowadays is a widely examined process being a possible alternative for traditional stone conservation methods. While research has been mostly limited to laboratory measurements, application connected, further in situ experiments should be performed in order to evaluate the applicability of the method. In our experiment, several bio-based treating compounds were compared, which have already been analyzed in different laboratories. Method for the treatment was based on the treatment of a French research group, and the compounds were applied on Hungarian porous limestone slabs, in situ. For inoculation bacteria strains Bacillus cereus and Myxococcus xanthus were used, and non-inoculated compounds were also analyzed. After the treatment, specimens were analyzed by means of discoloration effect, water absorption and migration characteristics. Almost all the treating compounds gave favorable or acceptable results for the examined properties, comparing to the properties measured in the non-cured state. Measurements on the chromatic- and on the water absorption aspects gave significant results, while further measurements are running for the more exact evaluation of the migration characteristics, i.e. effective migration depth and wetted volume.

  18. Probing the collective vibrational dynamics of a protein in liquid water by terahertz absorption spectroscopy.

    PubMed

    Xu, Jing; Plaxco, Kevin W; Allen, S James

    2006-05-01

    Biological polymers are expected to exhibit functionally relevant, global, and subglobal collective modes in the terahertz (THz) frequency range (i.e., picosecond timescale). In an effort to monitor these collective motions, we have experimentally determined the absorption spectrum of solvated bovine serum albumin (BSA) from 0.3 to 3.72 THz (10-124 cm(-1)). We successfully extract the terahertz molar absorption of the solvated BSA from the much stronger attenuation of water and observe in the solvated protein a dense, overlapping spectrum of vibrational modes that increases monotonically with increasing frequency. We see no evidence of distinct, strong, spectral features, suggesting that no specific collective vibrations dominate the protein's spectrum of motions, consistent with the predictions of molecular dynamics simulations and normal mode analyses of a range of small proteins. The shape of the observed spectrum resembles the ideal quadratic spectral density expected for a disordered ionic solid, indicating that the terahertz normal mode density of the solvated BSA may be modeled, to first order, as that of a three-dimensional elastic nanoparticle with an aperiodic charge distribution. Nevertheless, there are important detailed departures from that of a disordered inorganic solid or the normal mode densities predicted for several smaller proteins. These departures are presumably the spectral features arising from the unique molecular details of the solvated BSA. The techniques used here and measurements have the potential to experimentally confront theoretical calculations on a frequency scale that is important for macromolecular motions in a biologically relevant water environment.

  19. A simple fiber optic humidity sensor based on water-absorption characteristic of CAB

    NASA Astrophysics Data System (ADS)

    Li, Guang; Xu, Wei; Huang, Xuguang

    2015-02-01

    A simple fiber-optic relative humidity sensor based on cellulose acetate butyrate (CAB) and Fresnel reflection is proposed and investigated theoretically and experimentally. The sensing system is only composed of one light source, three optical couplers, two photo-detectors and two fiber sensing ends. The operation principle is based on relative Fresnel reflection and water-absorption characteristic of the CAB which simultaneously contains hydrophilic and hydrophobic groups. The water absorption process will lead to variation of the CAB's refractive index or permittivity. It has to be noted that the double-channel system can effectively eliminate the intensity fluctuation of the light source and the influence of the environment. In this paper, the relative humidity environments approximately ranging from 10 % to 100% are generated and measured both in the humidification and dehumidification processes, which shows a good repeatability and reveals a very good fitting feature with a high value of R2 above 0.99. It is of reflection type and can be simply extend to be a multi-point-monitoring system. The sensing system is of cost- effective, simple operation and high precision.

  20. Frontal bodies: novel structures involved in water vapour absorption by the desert burrowing cockroach, Arenivaga investigata.

    PubMed

    O'Donnell, M J

    1981-01-01

    Above 83% relative humidity, nymphs and adult females of the desert cockroach can condense water vapour on to a fluid layer covering protruded hypopharyngeal bladders. This fluid is produced by a pair of spheroidal bodies situated beneath the frons. Each such frontal body is connected by to the corresponding bladder by a groove in the epipharynx. During absorption, contraction of muscles connecting the frontal bodies to the frons causes them to move dorsally from the mandibles. Oscillation frequency increases with relative humidity or the application of nanoliter quantities of water to the bladders. Frontal bodies appear to be derived from invaginations of the integument, and consist of a mass of tough fibres containing protein and chitin. Fibres embed in a permeable plate which gives rise to the epipharyngeal groove. Tonofibrillae connect the fibres to elongate epidermal cells which are composed primarily of microtubules. The myoepidermal junction is characterized by fascia adherens. Frontal bodies resist tensile forces, but undergo changes in shape as they oscillate. Accompanying changes in hydrostatic pressure may move extracellular fluid across the plate and into the epipharyngeal groove. Possible roles of the fluid in the absorption process are discussed.

  1. Preconcentration of gold ions from water samples by modified organo-nanoclay sorbent prior to flame atomic absorption spectrometry determination.

    PubMed

    Afzali, Daryoush; Mostafavi, Ali; Mirzaei, Mohammad

    2010-09-15

    In this work, the applicability of modified organo nanoclay as a new and easy prepared solid sorbent for the preconcentration of trace amounts of Au(III) ion from water samples is studied. The organo nanoclay was modified with 5-(4'-dimethylamino benzyliden)-rhodanine and used as a sorbent for separation of Au(III) ions. The sorption of gold ions was quantitative in the pH range of 2.0-6.0. Quantitative desorption occurred with 6.0 mL of 1.0 mol L(-1) Na(2)S(2)O(3). The amount of eluted Au(III) was measured using flame atomic absorption spectrometry. In the initial solution the linear dynamic range was in the range of 0.45 ng mL(-1) to 10.0 microg mL(-1), the detection limit was 0.1 ng mL(-1) and the preconcentration factor was 105. Also, the relative standard deviation was +/-2.3% (n=8 and C=2.0 microg mL(-1)) and the maximum capacity of the sorbent was 3.9 mg of Au(III) per gram of modified organo nanoclay. The influences of the experimental parameters including sample pH, eluent volume and eluent type, sample volume, and interference of some ions on the recoveries of the gold ion were investigated. The proposed method was applied for preconcentration and determination of gold in different samples.

  2. Atmospheric pre-corrected differential absorption techniques to retrieve columnar water vapor: Theory and simulations

    SciTech Connect

    Borel, C.C.; Schlaepfer, D.

    1996-03-01

    Two different approaches exist to retrieve columnar water vapor from imaging spectrometer data: (1) Differential absorption techniques based on: (a) Narrow-Wide (N/W) ratio between overlapping spectrally wide and narrow channels (b) Continuum Interpolated Band Ratio (CIBR) between a measurement channel and the weighted sum of two reference channels; and (2) Non-linear fitting techniques which are based on spectral radiative transfer calculations. The advantage of the first approach is computational speed and of the second, improved retrieval accuracy. Our goal was to improve the accuracy of the first technique using physics based on radiative transfer. Using a modified version of the Duntley equation, we derived an {open_quote}Atmospheric Pre-corrected Differential Absorption{close_quote} (APDA) technique and described an iterative scheme to retrieve water vapor on a pixel-by-pixel basis. Next we compared both, the CIBR and the APDA using the Duntley equation for MODTRAN3 computed irradiances, transmissions and path radiance (using the DISORT option). This simulation showed that the CIBR is very sensitive to reflectance effects and that the APDA performs much better. An extensive data set was created with the radiative transfer code 6S over 379 different ground reflectance spectra. The calculated relative water vapor error was reduced significantly for the APDA. The APDA technique had about 8% (vs. over 35% for the CIBR) of the 379 spectra with a relative water vapor error of greater than {+-}5%. The APDA has been applied to 1991 and 1995 AVIRIS scenes which visually demonstrate the improvement over the CIBR technique.

  3. Fluctuation of the water environmental carrying capacity in a huge river-connected lake.

    PubMed

    Wang, Hua; Zhou, Yiyi; Tang, Yang; Wu, Mengan; Deng, Yanqing

    2015-03-30

    A new method, with the non-fully mixed coefficient (NFMC) considered, was put forward to calculate the water environmental carrying capacity (WECC) for huge river-connected lakes, of which the hydrological conditions always vary widely during a year. Poyang Lake, the most typical river-connected lake and the largest freshwater lake in China, was selected as the research area. Based on field investigations and numerical simulation, the monthly pollutant degradation coefficients and non-fully mixed coefficients of different lake regions were determined to explore the WECCs of COD, TN and TP of Poyang Lake in a common water year. It was found that under the hydrological conditions of a common water year the total WECCs of COD, TN and TP in the lake were respectively 181.9 × 104 t, 33.3 × 104 t and 1.86 × 104 t. Due to the varied lake water volume and self-purification ability, an evident temporal fluctuation of WECCs in Poyang Lake was observed. The dry seasons were characterized by a higher NFMCs but lower WECCs owing to the lower water level and degradation ability. Variation coefficients of COD and TN WECC were close to each other, of which the average level was about 58.5%, a little higher than that of TP.

  4. Dynamic registration of the absorption spectrum of water in the SiO(2) nanopores in high-frequency range.

    PubMed

    Sinitsa, L N; Lugovskoy, A A

    2010-11-28

    The high-frequency region was used to record the absorption spectrum of water in nanoscale pores during vacuum pumping or injection of water. The wide spectral range, which included the vibration overtones, allowed to resolve the structure of the absorption bands with variation of water concentration in the pores of SiO(2). The absorption bands of water clusters in the 4570-5400 cm(-1) range consist of well-resolved sub-bands with interpeak intervals of up to 580 cm(-1). When the pore diameter is decreased from 11.8 to 2.6 nm, the absorption bands of clusters in this frequency range are shifted by 530 cm(-1) in the direction of the water monomer which indicates an increase of hydrogen bond strength in confined water with an increase of the pore diameter. The spectrum recorded during water pumping is extremely variable in time, and the cluster dynamics in large pores (11.8 nm) differs greatly from the dynamics in small pores (2.6 nm). While all types of water clusters are removed from small pores uniformly, in the case of large pores, the water clusters relating to strong hydrogen bonds are removed from the sample at the beginning of the vacuum pumping and the loosely coupled clusters are removed later. The rate of this process is not steady and varies throughout pumping.

  5. [Absorption Characteristics of Particulates and CDOM in Waters of Chagan Lake and Xinlicheng Reservoir in Autumn].

    PubMed

    Li, Si-jia; Song, Kai-shan; Zhao, Ying; Mu, Guang-yi; Shao, Tian-tian; Ma, Jian-hang

    2016-01-15

    Field surveys and laboratory analysis were carried out in Chagan Lake and Xinlicheng Reservoir under different salinity conditions in September 2012. In the laboratory, the absorption coefficients of particulates and chromophoric dissolved organic matter (CDOM) were measured, aiming to compare the absorption features, source of optical active substances and relative contribution of optical active constituents over the range of PAR (400-700 nm) in Chagan Lake and Xinlicheng Reservoir. The results showed that the Chagan Lake and Xinlicheng Reservoir were water bodies with medium eutrophication in autumn by TAL nutrient index and the absorption spectra of particulates matters were similar to those of phytoplankton. For the Chagan Lake with high salinity( EC = 988. 87 micro S x cm(-1)), the total particulate absorption was dominated by the nonalgal particles, and the contribution rate was in the order of nonalgal particles > phytoplankton > CDOM. For the Xinlicheng Reservoir with low salinity (EC = 311.67 microS x -cm(-1)), the total particulate absorption was dominated by the phytoplankton, and the contribution rate was ranked as phytoplankton > nonalgal particles > CDOM. Positive correlation was observed between a(p) (440), a(p) (675), a(d) (440) and total suspended matter (TSM), inorganic suspended matter (ISM), organic suspended matter (OSM) and Chl-a respectively in Chagan Lake, with correlation coefficients all above 0.55. Positive correlation was observed between a(p)(440), a(p) (675) and Chl-a (0.77 and 0.85, P < 0.05) , so did a(d) (440) and ISM (0.74, P < 0.01), while negative correlation was observed between a(p) (440) and OSM in the Xinlicheng Reservoir. In terms of Chagan Lake, negative correlation was merely observed between a(g) (440) and OSM (-0.54, P < 0.05) , but not in the Xinlicheng Reservoir. Both Sg, which was calculated by the fitting absorption curve from 250 to 400 nm, and relative molecular weight M showed that Sg[ (0.021 +/- 0.001) m(-1)] in

  6. Anomalous components of supercooled water expansivity, compressibility, and heat capacity (Cp and Cv) from binary formamide+water solution studies

    NASA Astrophysics Data System (ADS)

    Oguni, M.; Angell, C. A.

    1983-06-01

    Recently reported heat capacity studies of N2H4+H2O and H2O2+H2O solutions, from which an anomalous component of the pure water behavior could be extracted by extrapolation, have been extended to a system NH2CHO+H2O which has the chemical stability needed to permit expansivity and compressibility measurements as well. Data accurate to ±2% for each of these properties as well as for the heat capacity are reported. The expansivity data support almost quantitatively an earlier speculative separation of the bulk and supercooled water expansivity into a ``normal'' (or ``background'') part and an ``anomalous'' part, the latter part fitting a critical law αanom=A(T/Ts-1)-γ with exponent γ=1.0. According to the present analysis, the anomalous part of the expansivity which is always negative, yields Ts in the range 225-228, γ in the range 1.28-1.0, depending on the choice of background extrapolation function. The normal contribution to the heat capacity obtained from the present work is intermediate in character to that from the previous two systems and leads to similar equation parameters. The normal contribution to the compressibility on the other hand is very different from that speculated earlier by Kanno and Angell and approximately verified by Conde et al. for ethanol-water solutions. The background component from the present analysis is ˜50% larger, with the result that the anomalous component, at least when values above 0 °C are included in the analysis, cannot be sensibly fitted to the critical point equation. The possible origin and interest content of these differences is discussed. Combination of the new thermodynamic data permit estimation of Cv values for the solution, and by extrapolation, a normal Cv component for water. The anomalous component of Cv for pure water obtained by difference has the form of a Shottky anomaly in contrast with the corresponding Cp component which diverges.

  7. Atmospheric absorption model for dry air and water vapor at microwave frequencies below 100 GHz derived from spaceborne radiometer observations

    NASA Astrophysics Data System (ADS)

    Wentz, Frank J.; Meissner, Thomas

    2016-05-01

    The Liebe and Rosenkranz atmospheric absorption models for dry air and water vapor below 100 GHz are refined based on an analysis of antenna temperature (TA) measurements taken by the Global Precipitation Measurement Microwave Imager (GMI) in the frequency range 10.7 to 89.0 GHz. The GMI TA measurements are compared to the TA predicted by a radiative transfer model (RTM), which incorporates both the atmospheric absorption model and a model for the emission and reflection from a rough-ocean surface. The inputs for the RTM are the geophysical retrievals of wind speed, columnar water vapor, and columnar cloud liquid water obtained from the satellite radiometer WindSat. The Liebe and Rosenkranz absorption models are adjusted to achieve consistency with the RTM. The vapor continuum is decreased by 3% to 10%, depending on vapor. To accomplish this, the foreign-broadening part is increased by 10%, and the self-broadening part is decreased by about 40% at the higher frequencies. In addition, the strength of the water vapor line is increased by 1%, and the shape of the line at low frequencies is modified. The dry air absorption is increased, with the increase being a maximum of 20% at the 89 GHz, the highest frequency considered here. The nonresonant oxygen absorption is increased by about 6%. In addition to the RTM comparisons, our results are supported by a comparison between columnar water vapor retrievals from 12 satellite microwave radiometers and GPS-retrieved water vapor values.

  8. Diesel driven low capacity heat pump for heating and hot water production

    NASA Astrophysics Data System (ADS)

    Hoefler, P.

    1982-08-01

    Heat pumps that reduce primary energy consumption for heating needs when they are driven by an internal combustion motor were studied. The heat produced as well from the heat pump as from the combustion in the diesel motor was used for home heating and hot water preparation. The objective was a 25kW capacity for a one familiy house. Material used should be standard, so a special design diesel motor or heat pump was not considered. An air/water cooled type diesel motor was coupled to a 12kW capacity heat pump for an outdoor temperature of 3 C using R12 freon as refrigerant. Description of all elements is given. Tests were in the laboratory and in a one family house. The expected efficiency factor of 1.34 could not be confirmed and an average annual value of only 1.05 is assumed. The diesel driven heat pump can not produce the energy savings hoped for.

  9. Removal Capacities of Polycyclic Aromatic Hydrocarbons (PAHs) by a Newly Isolated Strain from Oilfield Produced Water.

    PubMed

    Qi, Yi-Bin; Wang, Chen-Yu; Lv, Cheng-Yuan; Lun, Zeng-Min; Zheng, Cheng-Gang

    2017-02-22

    The polycyclic aromatic hydrocarbon (PAH)-degrading strain Q8 was isolated from oilfield produced water. According to the analysis of a biochemical test, 16S rRNA gene, house-keeping genes and DNA-DNA hybridization, strain Q8 was assigned to a novel species of the genus Gordonia. The strain could not only grow in mineral salt medium (MM) and utilize naphthalene and pyrene as its sole carbon source, but also degraded mixed naphthalene, phenanthrene, anthracene and pyrene. The degradation ratio of these four PAHs reached 100%, 95.4%, 73.8% and 53.4% respectively after being degraded by Q8 for seven days. A comparative experiment found that the PAHs degradation efficiency of Q8 is higher than that of Gordonia alkaliphila and Gordonia paraffinivorans, which have the capacities to remove PAHs. Fourier transform infrared spectra, saturate, aromatic, resin and asphaltene (SARA) and gas chromatography-mass spectrometry (GC-MS) analysis of crude oil degraded by Q8 were also studied. The results showed that Q8 could utilize n-alkanes and PAHs in crude oil. The relative proportions of the naphthalene series, phenanthrene series, thiophene series, fluorene series, chrysene series, C21-triaromatic steroid, pyrene, and benz(a)pyrene were reduced after being degraded by Q8. Gordonia sp. nov. Q8 had the capacity to remediate water and soil environments contaminated by PAHs or crude oil, and provided a feasible way for the bioremediation of PAHs and oil pollution.

  10. Removal Capacities of Polycyclic Aromatic Hydrocarbons (PAHs) by a Newly Isolated Strain from Oilfield Produced Water

    PubMed Central

    Qi, Yi-Bin; Wang, Chen-Yu; Lv, Cheng-Yuan; Lun, Zeng-Min; Zheng, Cheng-Gang

    2017-01-01

    The polycyclic aromatic hydrocarbon (PAH)-degrading strain Q8 was isolated from oilfield produced water. According to the analysis of a biochemical test, 16S rRNA gene, house-keeping genes and DNA–DNA hybridization, strain Q8 was assigned to a novel species of the genus Gordonia. The strain could not only grow in mineral salt medium (MM) and utilize naphthalene and pyrene as its sole carbon source, but also degraded mixed naphthalene, phenanthrene, anthracene and pyrene. The degradation ratio of these four PAHs reached 100%, 95.4%, 73.8% and 53.4% respectively after being degraded by Q8 for seven days. A comparative experiment found that the PAHs degradation efficiency of Q8 is higher than that of Gordonia alkaliphila and Gordonia paraffinivorans, which have the capacities to remove PAHs. Fourier transform infrared spectra, saturate, aromatic, resin and asphaltene (SARA) and gas chromatography–mass spectrometry (GC–MS) analysis of crude oil degraded by Q8 were also studied. The results showed that Q8 could utilize n-alkanes and PAHs in crude oil. The relative proportions of the naphthalene series, phenanthrene series, thiophene series, fluorene series, chrysene series, C21-triaromatic steroid, pyrene, and benz(a)pyrene were reduced after being degraded by Q8. Gordonia sp. nov. Q8 had the capacity to remediate water and soil environments contaminated by PAHs or crude oil, and provided a feasible way for the bioremediation of PAHs and oil pollution. PMID:28241412

  11. Phase Diagram and Heat Capacities of the Malonic Acid/Water System

    NASA Astrophysics Data System (ADS)

    Hansen, A.; Beyer, K. D.

    2003-12-01

    Malonic acid is one of the more ubiquitous dicarboxylic acids found in the atmosphere and is quite soluble in water. Therefore, its impact on particle/cloud droplet formation needs to be better understood through the study of the thermodynamics of its aqueous solutions. The liquid/solid phase diagram and solution heat capacities of the malonic acid/water binary system have been investigated using differential scanning calorimetry and infrared spectroscopy of thin films. We report here the first measurement of the ice melting envelope as well as the ice/malonic acid eutectic temperature and composition in this binary system. Evidence from both thermal analysis and infrared spectroscopy is shown for a malonic acid hydrate, possibly C3H4O4ṡ6H2O. We have observed the formation of this hydrate over a large range of concentrations, and have found it is a major fraction of samples within that region. We have also determined the enthalpy of fusion of malonic acid as well as the constant pressure heat capacities of solutions in the concentration range 5 - 55 wt% malonic acid from 323 K to the freezing point of each solution.

  12. Chitosan fibers enhanced gellan gum hydrogels with superior mechanical properties and water-holding capacity.

    PubMed

    Liu, Limei; Wang, Binghao; Gao, Yuan; Bai, Tong-Chun

    2013-08-14

    New hydrogels based on acetylated gellan gum (A-gellan) and chitosan fibers (F-chitosan) are prepared and coded as F-chitosan/A-gellan. Compared to A-gellan hydrogel, F-chitosan/A-gellan hydrogels show higher storage moduli and water-holding capacity. Specifically, the storage modulus of 2.0 F-chitosan/A-gellan (mass ratio of chitosan fibers and gellan gum is 2:1) hydrogels at regular frequency of 1 rad/s is 2.2 kPa, approximately 4.6 times more than that of the A-gellan hydrogel. In addition, the fractural morphology analysis of A-gellan and 2.0 F-chitosan/A-gellan hydrogels treated by different dry methods indicates that the 2.0 F-chitosan/A-gellan hydrogel has more stable macrostructure. Moreover, compared to A-gellan gel, 2.0 F-chitosan/A-gellan gel shows higher activation energy and water-holding capacity during dehydration and higher dielectric constant after dehydration. These results can be attributed to the special advantages of chitosan fibers, which are full of polar and hydrophilic amino group and can transfer the load applied on the hydrogels in fiber form.

  13. Optimizing available water capacity using microwave satellite data for improving irrigation management

    NASA Astrophysics Data System (ADS)

    Gupta, Manika; Bolten, John; Lakshmi, Venkat

    2015-04-01

    This work addresses the improvement of available water capacity by developing a technique for estimating soil hydraulic parameters through the utilization of satellite-retrieved near surface soil moisture. The prototype involves the usage of Monte Carlo analysis to assimilate historical remote sensing soil moisture data available from the Advanced Microwave Scanning Radiometer (AMSR-E) within the hydrological model. The main hypothesis used in this study is that near-surface soil moisture data contain useful information that can describe the effective hydrological conditions of the basin such that when appropriately In the method followed in this study the hydraulic parameters are derived directly from information on the soil moisture state at the AMSR-E footprint scale and the available water capacity is derived for the root zone by coupling of AMSR-E soil moisture with the physically-based hydrological model. The available capacity water, which refers to difference between the field capacity and wilting point of the soil and represent the soil moisture content at 0.33 bar and 15 bar respectively is estimated from the soil hydraulic parameters using the van Genuchten equation. The initial ranges of soil hydraulic parameters are taken in correspondence with the values available from the literature based on Soil Survey Geographic (SSURGO) database within the particular AMSR-E footprint. Using the Monte Carlo simulation, the ranges are narrowed in the region where simulation shows a good match between predicted and near-surface soil moisture from AMSR-E. In this study, the uncertainties in accurately determining the parameters of the nonlinear soil water retention function for large-scale hydrological modeling is the focus of the development of the Bayesian framework. Thus, the model forecasting has been combined with the observational information to optimize the model state and the soil hydraulic parameters simultaneously. The optimization process is divided into

  14. Study of Water Absorption in Raffia vinifera Fibres from Bandjoun, Cameroon

    PubMed Central

    Sikame Tagne, N. R.; Njeugna, E.; Fogue, M.; Drean, J.-Y.; Nzeukou, A.; Fokwa, D.

    2014-01-01

    The study is focused on the water diffusion phenomenon through the Raffia vinifera fibre from the stem. The knowledge on the behavior of those fibres in presence of liquid during the realization of biocomposite, is necessary. The parameters like percentage of water gain at the point of saturation, modelling of the kinetic of water absorption, and the effective diffusion coefficient were the main objectives. Along a stem of raffia, twelve zones of sampling were defined. From Fick's 2nd law of diffusion, a new model was proposed and evaluated compared to four other models at a constant temperature of 23°C. From the proposed model, the effective diffusion coefficient was deduced. The percentage of water gain was in the range of 303–662%. The proposed model fitted better to the experimental data. The estimated diffusion coefficient was evaluated during the initial phase and at the final phase. In any cross section located along the stem of Raffia vinifera, it was found that the effective diffusion coefficient increases from the periphery to the centre during the initial and final phases. PMID:24592199

  15. Gastric emptying and intestinal absorption of ingested water and saline by hypovolemic rats.

    PubMed

    Stricker, Edward M; Bykowski, Michael R; Hossler, Carrie A Smith; Curtis, Kathleen S; Smith, James C

    2009-12-07

    Recent experiments showed that in a one-bottle test conducted 16h after sc injection of polyethylene glycol (PEG) solution, hypovolemic rats consumed water or 0.30 M NaCl in an initial drinking episode but did not empty the ingested fluid from the stomach or absorb it from the small intestine very rapidly, certainly not as rapidly as when 0.15M NaCl was consumed (Smith et al., Am J Physiol 292: R2089-R2099, 2007). The present experiments examined the patterns of water and 0.30 M NaCl ingestion and the movement of consumed fluid through the gastrointestinal tract when PEG-treated rats were given a two-bottle delayed-access test. We found that both fluids always were consumed in the first drinking episode, that the fluid mixture ingested was equivalent to 0.10-0.15M NaCl, and that gastric emptying rate and net fluid absorption from the small intestine usually were much faster than when PEG-treated rats drank either water or hypertonic saline alone. Thus, ingestion of water and 0.30 M NaCl by hypovolemic rats in the same episode adaptively facilitated the movement into the circulation of a near-isotonic fluid that is ideal for restoring plasma volume deficits.

  16. Electric-field effects on the OH vibrational frequency and infrared absorption intensity for water

    NASA Astrophysics Data System (ADS)

    Hermansson, Kersti

    1993-07-01

    The variations of the anharmonic OH frequency and the infrared absorption intensity with field strength have been calculated for the uncoupled OH stretching vibration of a water molecule in a static, homogeneous electric field using ab initio methods at the MP4 level with a nearly saturated basis set. The OH frequency is found to be virtually independent of the field components perpendicular to the vibrating OH bond. For the parallel component, the frequency vs field curve is close to quadratic, with a maximum for a slightly negative (directed from H to O) field strength. The external field perturbation, defined as Vext(E∥,rOH)=Vtot(E∥, rOH)-Vfree(rOH), is found to be closely linear in rOH, except when the field strength E∥ is both large and negative. The linear external force constant is almost perfectly accounted for by the sum of two terms, -E∥ṡdμ∥free/drOH and -1/2ṡE∥ṡ∂μ∥induced/∂rOH. These derivatives are quite insensitive to the choice of basis-set. The ∂μ∥induced/∂rOH derivative is approximately proportional to E∥, and gives rise to the arclike shape of the frequency vs field curve. The frequency maximum occurs where ∂μ∥tot/∂rOH≊0. It is the sign of dμ∥free/drOH which determines that the frequency maximum occurs at a negative field strength for water (but at a positive field strength for OH-, for example), i.e., that a frequency red-shift (blue-shift for OH-) occurs when the molecule is bound. The linear relationship between the infrared absorption intensity and frequency of the water OH vibration is derived.

  17. Baking loss of bread with special emphasis on increasing water holding capacity.

    PubMed

    Kotoki, D; Deka, S C

    2010-01-01

    Potato flour (PF), hydroxypropyl methylcellulose (HPMC) and honey were used as baking agents and their effects on baking loss and sensory quality were studied. PF at 1, 2 and 4% levels decreased baking loss followed by HPMC and honey. Water absorption was substantially high with the HPMC (70.8-80.8%) and PF (61.7-71.7%) compared to honey and normal standard bread. PF incorporation increased shelf-life (6-7 days) as compared to HPMC and honey. HPMC incorporated bread had higher moisture content (36.8-38.0%) followed by PF (34.5-35.8%) and honey (34.7%). The ash content was in the order of PF (1%) > honey (4%) > PF (2%) > normal bread > HPMC (0.5 g) > PF (4%) > HPMC (1 g) > HPMC (1.5 g). PF incorporated bread had sensorily highest acceptance followed by HPMC and honey.

  18. Pressure perturbation calorimetry, heat capacity and the role of water in protein stability and interactions.

    PubMed

    Cooper, A; Cameron, D; Jakus, J; Pettigrew, G W

    2007-12-01

    It is widely acknowledged, and usually self-evident, that solvent water plays a crucial role in the overall thermodynamics of protein stabilization and biomolecular interactions. Yet we lack experimental techniques that can probe unambiguously the nature of protein-water or ligand-water interactions and how they might change during protein folding or ligand binding. PPC (pressure perturbation calorimetry) is a relatively new technique based on detection of the heat effects arising from application of relatively small pressure perturbations (+/-5 atm; 1 atm=101.325 kPa) to dilute aqueous solutions of proteins or other biomolecules. We show here how this can be related to changes in solvation/hydration during protein-protein and protein-ligand interactions. Measurements of 'anomalous' heat capacity effects in a wide variety of biomolecular interactions can also be related to solvation effects as part of a quite fundamental principle that is emerging, showing how the apparently unusual thermodynamics of interactions in water can be rationalized as an inevitable consequence of processes involving the co-operative interaction of multiple weak interactions. This leads to a generic picture of the thermodynamics of protein folding stabilization in which hydrogen-bonding plays a much more prominent role than has been hitherto supposed.

  19. Heat capacities of the water + lithium bromide + ethanolamine and water + lithium bromide + 1,3-propanediol systems

    SciTech Connect

    Kim, J.S.; Park, Y.; Lee, H.; Yu, S.I.

    1997-03-01

    Heat capacities of the water + lithium bromide + ethanolamine (LiBr/H{sub 2}N(CH{sub 2}){sub 2}OH mass ratio = 3.5) and water + lithium bromide + 1,3-propanediol (LiBr/HO(CH{sub 2}){sub 3}OH mass ratio = 3.5) systems were measured by using an isoperibol solution calorimeter at four temperatures (283.15, 298.15, 313.15, and 333.15 K) and absorbent (LiBr + H{sub 2}N(CH{sub 2}){sub 2}OH and LiBr + HO(CH{sub 2}){sub 3}OH) concentration ranges of (29.2 to 70.7)% and (30.7 to 68.3)%, respectively. The measured values were fitted with a simple equation by a least-squares method and the average absolute deviations between experimental and calculated values were 0.21% for the water + lithium bromide + ethanolamine system and 0.15% for the water + lithium bromide + 1,3-propanediol system, respectively.

  20. Differential Absorption Lidar (DIAL) Measurements of Atmospheric Water Vapor Utilizing Robotic Aircraft

    NASA Technical Reports Server (NTRS)

    Hoang, Ngoc; DeYoung, Russell J.; Prasad, Coorg R.; Laufer, Gabriel

    1998-01-01

    A new unpiloted air vehicle (UAV) based water vapor DIAL system will be described. This system is expected to offer lower operating costs, longer test duration and severe weather capabilities. A new high-efficiency, compact, light weight, diode-pumped, tunable Cr:LiSAF laser will be developed to meet the UAV payload weight and size limitations and its constraints in cooling capacity, physical size and payload. Similarly, a new receiver system using a single mirror telescope and an avalanche photo diode (APD) will be developed. Projected UAV parameters are expected to allow operation at altitudes up to 20 km, endurance of 24 hrs and speed of 400 km/hr. At these conditions measurements of water vapor at an uncertainty of 2-10% with a vertical resolution of 200 m and horizontal resolution of 10 km will be possible.

  1. Comparison of x-ray absorption spectra between water and ice: New ice data with low pre-edge absorption cross-section

    SciTech Connect

    Sellberg, Jonas A.; Nilsson, Anders; Kaya, Sarp; Segtnan, Vegard H.; Chen, Chen; Tyliszczak, Tolek; Ogasawara, Hirohito; Nordlund, Dennis; Pettersson, Lars G. M.

    2014-07-21

    The effect of crystal growth conditions on the O K-edge x-ray absorption spectra of ice is investigated through detailed analysis of the spectral features. The amount of ice defects is found to be minimized on hydrophobic surfaces, such as BaF{sub 2}(111), with low concentration of nucleation centers. This is manifested through a reduction of the absorption cross-section at 535 eV, which is associated with distorted hydrogen bonds. Furthermore, a connection is made between the observed increase in spectral intensity between 544 and 548 eV and high-symmetry points in the electronic band structure, suggesting a more extended hydrogen-bond network as compared to ices prepared differently. The spectral differences for various ice preparations are compared to the temperature dependence of spectra of liquid water upon supercooling. A double-peak feature in the absorption cross-section between 540 and 543 eV is identified as a characteristic of the crystalline phase. The connection to the interpretation of the liquid phase O K-edge x-ray absorption spectrum is extensively discussed.

  2. Laboratory Measurements of the 940, 1130, and 1370 nm Water Vapor Absorption Band Profiles

    NASA Technical Reports Server (NTRS)

    Giver, Lawrence P.; Gore, Warren J.; Pilewskie, P.; Freedman, R. S.; Chackerian, C., Jr.; Varanasi, P.

    2001-01-01

    We have used the solar spectral flux radiometer (SSFR) flight instrument with the Ames 25 meter base-path White cell to obtain about 20 moderate resolution (8 nm) pure water vapor spectra from 650 to 1650 nm, with absorbing paths from 806 to 1506 meters and pressures up to 14 torr. We also obtained a set at 806 meters with several different air-broadening pressures. Model simulations were made for the 940, 1130, and 1370 nm absorption bands for some of these laboratory conditions using the Rothman, et al HITRAN-2000 linelist. This new compilation of HITRAN includes new intensity measurements for the 940 nm region. We compared simulations for our spectra of this band using HITRAN-2000 with simulations using the prior HITRAN-1996. The simulations of the 1130 nm band show about 10% less absorption than we measured. There is some evidence that the total intensity of this band is about 38% stronger than the sum of the HITRAN line intensities in this region. In our laboratory conditions the absorption depends approximately on the square root of the intensity. Thus, our measurements agree that the band is stronger than tabulated in HITRAN, but by about 20%, substantially less than the published value. Significant differences have been shown between Doppler-limited resolution spectra of the 1370 nm band obtained at the Pacific Northwest National Laboratory and HITRAN simulations. Additional new intensity measurements in this region are continuing to be made. We expect the simulations of our SSFR lab data of this band will show the relative importance of improving the HITRAN line intensities of this band for atmospheric measurements.

  3. Absorption/desorption of hydrogen isotopes and isotopic waters by Zr-alloy getters

    SciTech Connect

    Ichimura, K.; Matsuyama, M.; Watanabe, K.; Takeuchi, T.

    1988-07-01

    Zr-alloy getters have been applied to tritium handling and vacuum conditioning for fusion devices. Some of their properties, however, should be improved to apply them in future devices. From this viewpoint, we have studied the effects of alloying on the getter properties of Zr alloys. We found that the activation energy of absorption and desorption of hydrogen varied considerably with alloying. The activation energy for hydrogen absorption was 0.74 for Zr/sub 61/Al/sub 39/, 0.01 for Zr/sub 57/V/sub 36/Fe/sub 7/, 0.63 for Zr/sub 67/Ni/sub 33/, and 2.8 kcal/mol for Zr/sub 85/Ni/sub 15/, whereas that for Zr was 2.6 kcal/mol. The heat of hydrogen absorption was 27.8 kcal/mol for Zr: it changed with alloying as 32.0--33.4 (Zr/sub 61/Al/sub 39/), 27.8--28.4 (Zr/sub 57/V/sub 36/Fe/sub 7/), 29.0 (Zr/sub 67/Ni/sub 33/), and 28.0 (Zr/sub 85/Ni/sub 15/). In addition, the ratio of the pumping speed of water vapor to that of hydrogen at room temperature varied with alloying element: for example, 1/40 for Zr/sub 57/V/sub 36/Fe/sub 7/ and 1/4 for Zr/sub 67/Ni/sub 33/. The alloying effects mentioned above are considered due to modification of the electronic and/or geometric structure of Zr with alloying.

  4. Heat capacity and density of potassium iodide solutions in mixed N-methylpyrrolidone-water solvent at 298.15 K

    NASA Astrophysics Data System (ADS)

    Novikov, A. N.

    2014-10-01

    The heat capacity and density of potassium iodide solutions in a mixed N-methylpyrrolidone (MP)-water solvent with a low content of the organic component are measured via calorimetry and densimetry at 298.15 K. Standard partial molal heat capacities and volumes of potassium iodide in MP-water mixtures are calculated. Standard heat capacities and volumes of potassium and iodide ions are determined. The character of the changes in heat capacity and volume are discussed on the basis of calculating additivity coefficients δ c and δ v upon the mixing of isomolal binary solutions KI-MP and KI-water, depending on the composition of the MP-H2O mixture and the concentration of the electrolyte.

  5. Simulation and performance analysis of a quadruple-effect lithium bromide-water absorption

    SciTech Connect

    Grossman, G.; Zaltash, A.; DeVault, R.C.

    1994-04-01

    In order to investigate the possibility of improving utilization of high temperature heat sources, such as natural gas, for absorption chillers, performance simulation has been conducted for a quadruple-effect lithium bromide-water cycle, capable of substantial performance improvement over state-of-the-art double-effect cycles. The system investigated includes four condensers and four desorbers coupled together, forming an extension of the conventional double-effect cycle; based on prior experience, a parallel flow system was perferred over series flow, and double-condenser coupling (DCC) was employed, extending from triple-effect cycles, to further improve performance. A modular computer code for simulation of absorption systems (ABSIM) was used to investigate the performances of the cycle. The simulation was carried out over a range of operating conditions, including investigation of the influence of some major design parameters. A coefficient of performance in the neighborhood of 2.0 (cooling) was calculated at the design point, with a heat supply temperature of 600{degrees}F at the solution outlet from the high temperature desorber. With some optimization of the weak (pumped) solution flowrate and of the solution split among the four desorbers, this COP may be raised above 2.2, without any increase in the heat transfer surface of the system`s components.

  6. Improved intestinal absorption of water-soluble drugs by acetylation of G2 PAMAM dendrimer nanocomplexes in rat.

    PubMed

    Yan, Chengyun; Gu, Jiwei; Lv, Yuguang; Shi, Weiguo; Jing, Hongying

    2017-03-16

    In search of an effective and less toxic absorption enhancer, we synthesized primary amine acetylation of generation 2 polyamidoamine (G2 PAMAM) dendrimer (Ac-G2) by the reaction of G2 PAMAM dendrimer with acetic anhydride, and evaluated the effects of Ac-G2 on the intestinal absorption of poorly absorbable water-soluble drugs using an in situ closed-loop method in rats. The results indicated that Ac50-G2 had a greatest absorption enhancing effect for 5(6)-carboxyfluorescein (CF) in various acetylation levels of G2 PAMAM dendrimers. Ac50-G2 with various concentrations (0.1-1.0%, w/v) could significantly improve the intestinal absorption of alendronate, CF, and fluorescein isothiocyanate-labeled dextrans (FD4), although they did not enhance the absorption of macromolecular drug of FD10, and the absorption enhancement effect of Ac50-G2 was concentration-dependent. Furthermore, we examined the intestinal membrane damage with or without Ac50-G2. The results displayed Ac50-G2 at lower concentrations (0.1-0.5%, w/v) did not cause any observed toxic effect to the intestinal membranes. These findings suggested Ac50-G2 at lower concentrations (below 0.5%, w/v) might be promising as an effective and safe absorption enhancers to promote the intestinal absorption of poorly absorbable drugs.

  7. Geology, water resources and usable ground-water storage capacity of part of Solano County, California

    USGS Publications Warehouse

    Thomasson, H.G.; Olmsted, F.H.; LeRoux, E.F.

    1960-01-01

    The area described is confined largely to the valley-floor and foothill lands of Solano County, which lies directly between Sacramento, the State capital, and San Francisco. The area is considered in two subareas: The Putah area, which extends from Putah Creek southward to the Montezuma Hills and from the foothills of the Coast Ranges eastward to the west edge of the Yolo Bypass; and the Suisun-Fairfield area, which is to the southwest in the notch in the Coast Ranges through which the waters of the Great Central Valley of California reach San Francisco Bay. There are no known hydrologic interconnections between the two subareas, through either surface streams or underground aquifers. The climate of the area is characterized by warm, rainless summers and by cool winters in which temperatures seldom drop much below freezing. The rainfall ranges from about 17 inches per year along the east side to perhaps 24 inches in the foothills to the west, and irrigation is necessary for all crops except dry-farmed grains, pastures, and some orchards. PUTAH AREA The Putah area occupies the southwestern corner of the Sacramento Valley, a topographic and structural basin underlain by a thick accumulation of sediments eroded from the surrounding hills and mountains by the Sacramento River and its tributaries. The eastern Coast Ranges and foothills lying west of the Sacramento Valley are a generally northward-trending belt of eastward-dipping sedimentary rocks that range in age from Cretaceous to Pleistocene. Successively younger strata are exposed eastward, and the essentially undeformed deposits of late Pleistocene and Recent age that immediately underlie the valley lap onto the tilted sediments of the foothills. Most of the streams of the Putah area rise east of the high ridge of Cretaceous rocks marking the western boundaries of Solano and Yolo Counties, but Putah Creek, the largest stream in the area, rises far west of that ridge and flows across it in a deep, narrow canyon

  8. Remote-Sensing Technique for Determination of the Volume Absorption Coefficient of Turbid Water

    NASA Astrophysics Data System (ADS)

    Sydor, Michael; Arnone, Robert A.; Gould, Richard W., Jr.; Terrie, Gregory E.; Ladner, Sherwin D.; Wood, Christoper G.

    1998-07-01

    We use remote-sensing reflectance from particulate R rs to determine the volume absorption coefficient a of turbid water in the 400 700-nm spectral region. The calculated and measured values of a ( ) show good agreement for 0 . 5 a 10 (m 1 ). To determine R rs from a particulate, we needed to make corrections for remote-sensing reflectance owing to surface roughness S rs . We determined the average spectral distribution of S rs from the difference in total remote-sensing reflectance measured with and without polarization. The spectral shape of S rs showed an excellent fit to theoretical formulas for glare based on Rayleigh and aerosol scattering from the atmosphere.

  9. Predictions of silicon avalanche photodiode detector performance in water vapor differential absorption lidar

    NASA Technical Reports Server (NTRS)

    Kenimer, R. L.

    1988-01-01

    Performance analyses are presented which establish that over most of the range of signals expected for a down-looking differential absorption lidar (DIAL) operated at 16 km the silicon avalanche photodiode (APD) is the preferred detector for DIAL measurements of atmospheric water vapor in the 730 nm spectral region. The higher quantum efficiency of the APD's, (0.8-0.9) compared to a photomultiplier's (0.04-0.18) more than offsets the higher noise of an APD receiver. In addition to offering lower noise and hence lower random error the APD's excellent linearity and impulse recovery minimize DIAL systematic errors attributable to the detector. Estimates of the effect of detector system parameters on overall random and systematic DIAL errors are presented, and performance predictions are supported by laboratory characterization data for an APD receiver system.

  10. Multiband InGaN nanowires with enhanced visible photon absorption for efficient photoelectrochemical water splitting

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, M.; Gopalakrishnan, S.; Bhalerao, G. M.; Jeganathan, K.

    2017-01-01

    Ultralong compositional tunable InGaN nanowires as a photoanode, grown by chemical vapour deposition technique using catalyst-free approach, exhibits high efficiency solar water splitting for the first time without co-catalyst. The high density of unique ultralong InGaN nanowires with high intense multiband emission in the visible region improves the absorption of photon, thereby significantly increasing the photocurrent density of ∼32 mA/cm2 at 1.0 V against Pt counter electrode. The small diameter of InGaN nanowires favours the diffusion of the charge carriers to the surface before recombination which results in enhanced solar energy conversion efficiency. Multiband InGaN nanowires demonstrate a maximum applied bias photon-to-current efficiency of ∼16.19% at 0.34 V under AM1.5G one sun illumination.

  11. Comparison of path integral molecular dynamics methods for the infrared absorption spectrum of liquid water

    NASA Astrophysics Data System (ADS)

    Habershon, Scott; Fanourgakis, George S.; Manolopoulos, David E.

    2008-08-01

    The ring polymer molecular dynamics (RPMD) and partially adiabatic centroid molecular dynamics (PA-CMD) methods are compared and contrasted in an application to the infrared absorption spectrum of a recently parametrized flexible, polarizable, Thole-type potential energy model for liquid water. Both methods predict very similar spectra in the low-frequency librational and intramolecular bending region at wavenumbers below 2500 cm-1. However, the RPMD spectrum is contaminated in the high-frequency O-H stretching region by contributions from the internal vibrational modes of the ring polymer. This problem is avoided in the PA-CMD method, which adjusts the elements of the Parrinello-Rahman mass matrix so as to shift the frequencies of these vibrational modes beyond the spectral range of interest. PA-CMD does not require any more computational effort than RPMD and it is clearly the better of the two methods for simulating vibrational spectra.

  12. Diffusion Coefficients of Water and Leachables in Methacrylate-based Crosslinked Polymers using Absorption Experiments

    PubMed Central

    Parthasarathy, Ranganathan; Misra, Anil; Park, Jonggu; Ye, Qiang; Spencer, Paulette

    2012-01-01

    The diffusion of water into dentin adhesive polymers and leaching of unpolymerized monomer from the adhesive are linked to their mechanical softening and hydrolytic degradation. Therefore, diffusion coefficient data are critical for the mechanical design of these polymeric adhesives. In this study, diffusion coefficients of water and leachables were obtained for sixteen methacrylate-based crosslinked polymers using absorption experiments. The experimental mass change data was interpreted using numerical solution of the two-dimensional diffusion equations. The calculated diffusion coefficients varied from 1.05 × 10−8 cm2/sec (co-monomer TMTMA) to 3.15 × 10−8 cm2/sec (co-monomer T4EGDMA). Correlation of the diffusion coefficients with crosslink density and hydrophilicity showed an inverse trend (R2 = 0.41). The correlation of diffusion coefficient with crosslink density and hydrophilicity are closer for molecules differing by simple repeat units (R2 = 0.95). These differences in the trends reveal mechanisms of interaction of the diffusing water with the polymer structure. PMID:22430592

  13. Evaluation of tropospheric water vapor profiling using eye-safe, infrared differential absorption lidar

    SciTech Connect

    Rye, B.J. |; Machol, J.L.; Grund, C.J.; Hardesty, R.M.

    1996-05-14

    Continuous, high quality profiles of water vapor, free of systematic bias, and of moderate temporal and spatial resolution are fundamental to the success of the ARM CART program. In addition, these should be acquired over long periods at low operational and maintenance cost. The development and verification of realistic climate model parameterizations for clouds and net radiation balance, and the correction of other CART site sensor observations for interferences due to the presence of water vapor are critically dependent on water vapor profile measurements. To date, application of profiles have been limited by vertical resolution and uniqueness and high operating cost, or diminished daytime performance, lack of eye-safety, and high maintenance cost. Recent developments in infrared laser and detector technology make possible compact IR differential absorption lidar (DIAL) systems at eye-safe wavelengths. In the studies reported here, we develop DIAL system performance models and examine the potential of solving some of the shortcomings of previous methods using parameters representative of current technologies. These simulations are also applied to determine the strengths and weaknesses unique to the DIAL method for this application.

  14. Non-Fickian behavior of water absorption in an epoxy-amidoamine network

    NASA Astrophysics Data System (ADS)

    Brethous, R.; Colin, X.; Fayolle, B.; Gervais, M.

    2016-05-01

    The water absorption in a DGEBA-amidoamine network synthesized with an amine excess was studied between 10 and 90% RH at 30, 50 and 70°C. This quasi-ideal epoxy network displays deviations from the classical Fick's behavior after the transient period. The amplitude of these deviations is an increasing function of both the relative humidity and temperature. In a first approximation, it was assumed that they result exclusively from the hydrolysis of the elastically active chains constituted by the amidoamine hardener. Indeed, at low conversion ratios, the reaction of amides with water and the accumulation of dangling chains with highly polar extremities (carboxylic acids) in the epoxy network could explain the progressive increase in the equilibrium water mass uptake m∞ over time. At highest conversions ratios, i.e. when the probability of having two hydrolysis events on a same elastically active chain cannot be ignored, the physical loss of short macromolecular fragments (of diacid type) from the epoxy network could then explain the decrease in m∞ over time. Complementary physico-chemical analyses are in progress to check these assumptions.

  15. The role of storage capacity in coping with intra- and inter-annual water variability in large river basins

    NASA Astrophysics Data System (ADS)

    Gaupp, Franziska; Hall, Jim; Dadson, Simon

    2015-12-01

    Societies and economies are challenged by variable water supplies. Water storage infrastructure, on a range of scales, can help to mitigate hydrological variability. This study uses a water balance model to investigate how storage capacity can improve water security in the world’s 403 most important river basins, by substituting water from wet months to dry months. We construct a new water balance model for 676 ‘basin-country units’ (BCUs), which simulates runoff, water use (from surface and groundwater), evaporation and trans-boundary discharges. When hydrological variability and net withdrawals are taken into account, along with existing storage capacity, we find risks of water shortages in the Indian subcontinent, Northern China, Spain, the West of the US, Australia and several basins in Africa. Dividing basins into BCUs enabled assessment of upstream dependency in transboundary rivers. Including Environmental Water Requirements into the model, we find that in many basins in India, Northern China, South Africa, the US West Coast, the East of Brazil, Spain and in the Murray basin in Australia human water demand leads to over-abstraction of water resources important to the ecosystem. Then, a Sequent Peak Analysis is conducted to estimate how much storage would be needed to satisfy human water demand whilst not jeopardizing environmental flows. The results are consistent with the water balance model in that basins in India, Northern China, Western Australia, Spain, the US West Coast and several basins in Africa would need more storage to mitigate water supply variability and to meet water demand.

  16. Calculation of Vibrational and Electronic Excited-State Absorption Spectra of Arsenic-Water Complexes Using Density Functional Theory

    DTIC Science & Technology

    2016-06-03

    of Arsenic- Water Complexes Using Density Functional Theory June 3, 2016 Approved for public release; distribution is unlimited. L. Huang S.g...NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Calculation of Vibrational and Electronic Excited-State Absorption Spectra of Arsenic- Water Complexes Using... water molecules should be associated with response features that are intermediate between that of isolated molecules and that of a bulk system. DFT and

  17. Water absorption of poly(methyl methacrylate) measured by vertical interference microscopy.

    PubMed

    N'Diaye, Mambaye; Pascaretti-Grizon, Florence; Massin, Philippe; Baslé, Michel Felix; Chappard, Daniel

    2012-08-07

    PMMA (poly(methyl methacrylate)) is widely used to prepare orthopedic cements. They are in direct contact with cells and body fluids. PMMA, despite its hydrophobic nature, can absorb ~2% w/w water. We have evaluated by vertical interference microscopy if water absorption can produce a significant swelling in different types of PMMA blocks: pure, with a plasticizer, with a cross-linker, and in two types of commercial bone cements. Graphite rods which do not swell in water were used as internal standard. Hardness, indentation modulus, plastic, and elastic works were determined by nanoindentation under a 25mN fixed force. Vertical interference microscopy was used to image the polymer in the dry state and hydrated states (after 24 h in distilled water). On the surface of the polished polymers (before and after hydration), we measured roughness by the fractal dimension, the swelling in the vertical and the lateral directions. For each polymer block, four images were obtained and values were averaged. Comparison and standardization of the images in the dry and hydrated states were done with Matlab software. The average value measured on the graphite rod between the two images (dried and hydrated) was used for standardization of the images which were visualized in 3D. After grinding, a small retraction was noticeable between the surface of the rod and the polymers. A retraction ring was also visible around the graphite rod. After hydration, only the pure PMMA and bone cements had a significant swelling in the vertical direction. The presence of polymer beads in the cements limited the swelling in the lateral direction. Swelling parameters correlated with the nanoindentation data. PMMA can swell by absorbing a small amount of water and this induces a swelling that varies with the polymer composition and particle inclusions.

  18. Depth of cinder deposits and water-storage capacity at Cinder Lake, Coconino County, Arizona

    USGS Publications Warehouse

    Macy, Jamie P.; Amoroso, Lee; Kennedy, Jeff; Unema, Joel

    2012-01-01

    The 2010 Schultz fire northeast of Flagstaff, Arizona, burned more than 15,000 acres on the east side of San Francisco Mountain from June 20 to July 3. As a result, several drainages in the burn area are now more susceptible to increased frequency and volume of runoff, and downstream areas are more susceptible to flooding. Resultant flooding in areas downgradient of the burn has resulted in extensive damage to private lands and residences, municipal water lines, and roads. Coconino County, which encompasses Flagstaff, has responded by deepening and expanding a system of roadside ditches to move flood water away from communities and into an area of open U.S. Forest Service lands, known as Cinder Lake, where rapid infiltration can occur. Water that has been recently channeled into the Cinder Lake area has infiltrated into the volcanic cinders and could eventually migrate to the deep regional groundwater-flow system that underlies the area. How much water can potentially be diverted into Cinder Lake is unknown, and Coconino County is interested in determining how much storage is available. The U.S. Geological Survey conducted geophysical surveys and drilled four boreholes to determine the depth of the cinder beds and their potential for water storage capacity. Results from the geophysical surveys and boreholes indicate that interbedded cinders and alluvial deposits are underlain by basalt at about 30 feet below land surface. An average total porosity for the upper 30 feet of deposits was calculated at 43 percent for an area of 300 acres surrounding the boreholes, which yields a total potential subsurface storage for Cinder Lake of about 4,000 acre-feet. Ongoing monitoring of storage change in the Cinder Lake area was initiated using a network of gravity stations.

  19. Heat Capacity Anomaly Near the Lower Critical Consolute Point of Triethylamine-Water

    NASA Technical Reports Server (NTRS)

    Flewelling, Anne C.; DeFonseka, Rohan J.; Khaleeli, Nikfar; Partee, J.; Jacobs, D. T.

    1996-01-01

    The heat capacity of the binary liquid mixture triethylamine-water has been measured near its lower critical consolute point using a scanning, adiabatic calorimeter. Two data runs are analyzed to provide heat capacity and enthalpy data that are fitted by equations with background terms and a critical term that includes correction to scaling. The critical exponent a was determined to be 0.107 +/- 0.006, consistent with theoretical predictions. When alpha was fixed at 0.11 to determine various amplitudes consistently, our values of A(+) and A(-) agreed with a previous heat capacity measurement, but the value of A(-) was inconsistent with values determined by density or refractive index measurements. While our value for the amplitude ratio A(+)/ A(-) = 0.56 +/- 0.02 was consistent with other recent experimental determinations in binary liquid mixtures, it was slightly larger than either theoretical predictions or recent experimental values in liquid-vapor systems. The correction to scaling amplitude ratio D(+)/D(-) = 0.5 +/- 0.1 was half of that predicted. As a result of several more precise theoretical calculations and experimental determinations, the two-scale-factor universality ratio X, which we found to be 0.019 +/- 0.003, now is consistent among experiments and theories. A new 'universal' amplitude ratio R(sup +/-)(sub Bcr) involving the amplitudes for the specific heat was tested. Our determination of R(sup +/-)(sub Bcr) = -0.5 +/- 0.1 and R(sup -)(sub Bcr) = 1.1 +/- 0.1 is smaller in magnitude than predicted and is the first such determination in a binary fluid mixture.

  20. VARIABILITY OF WATER AND OXYGEN ABSORPTION BANDS IN THE DISK-INTEGRATED SPECTRA OF EARTH

    SciTech Connect

    Fujii, Yuka; Suto, Yasushi; Turner, Edwin L.

    2013-03-10

    We study the variability of major atmospheric absorption features in the disk-integrated spectra of Earth with future application to Earth-analogs in mind, concentrating on the diurnal timescale. We first analyze observations of Earth provided by the EPOXI mission, and find 5%-20% fractional variation of the absorption depths of H{sub 2}O and O{sub 2} bands, two molecules that have major signatures in the observed range. From a correlation analysis with the cloud map data from the Earth Observing Satellite (EOS), we find that their variation pattern is primarily due to the uneven cloud cover distribution. In order to account for the observed variation quantitatively, we consider a simple opaque cloud model, which assumes that the clouds totally block the spectral influence of the atmosphere below the cloud layer, equivalent to assuming that the incident light is completely scattered at the cloud top level. The model is reasonably successful, and reproduces the EPOXI data from the pixel-level EOS cloud/water vapor data. A difference in the diurnal variability patterns of H{sub 2}O and O{sub 2} bands is ascribed to the differing vertical and horizontal distribution of those molecular species in the atmosphere. On Earth, the inhomogeneous distribution of atmospheric water vapor is due to the existence of its exchange with liquid and solid phases of H{sub 2}O on the planet's surface on a timescale short compared with atmospheric mixing times. If such differences in variability patterns were detected in spectra of Earth-analogs, it would provide the information on the inhomogeneous composition of their atmospheres.

  1. Evaluating the Metal Tolerance Capacity of Microbial Communities Isolated from Alberta Oil Sands Process Water.

    PubMed

    Frankel, Mathew L; Demeter, Marc A; Lemire, Joe A; Turner, Raymond J

    2016-01-01

    Anthropogenic activities have resulted in the intensified use of water resources. For example, open pit bitumen extraction by Canada's oil sands operations uses an estimated volume of three barrels of water for every barrel of oil produced. The waste tailings-oil sands process water (OSPW)-are stored in holding ponds, and present an environmental concern as they are comprised of residual hydrocarbons and metals. Following the hypothesis that endogenous OSPW microbial communities have an enhanced tolerance to heavy metals, we tested the capacity of planktonic and biofilm populations from OSPW to withstand metal ion challenges, using Cupriavidus metallidurans, a known metal-resistant organism, for comparison. The toxicity of the metals toward biofilm and planktonic bacterial populations was determined by measuring the minimum biofilm inhibitory concentrations (MBICs) and planktonic minimum inhibitory concentrations (MICs) using the MBEC ™ assay. We observed that the OSPW community and C. metallidurans had similar tolerances to 22 different metals. While thiophillic elements (Te, Ag, Cd, Ni) were found to be most toxic, the OSPW consortia demonstrated higher tolerance to metals reported in tailings ponds (Al, Fe, Mo, Pb). Metal toxicity correlated with a number of physicochemical characteristics of the metals. Parameters reflecting metal-ligand affinities showed fewer and weaker correlations for the community compared to C. metallidurans, suggesting that the OSPW consortia may have developed tolerance mechanisms toward metals present in their environment.

  2. Evaluating the Metal Tolerance Capacity of Microbial Communities Isolated from Alberta Oil Sands Process Water

    PubMed Central

    Frankel, Mathew L.; Demeter, Marc A.; Lemire, Joe A.; Turner, Raymond J.

    2016-01-01

    Anthropogenic activities have resulted in the intensified use of water resources. For example, open pit bitumen extraction by Canada’s oil sands operations uses an estimated volume of three barrels of water for every barrel of oil produced. The waste tailings–oil sands process water (OSPW)–are stored in holding ponds, and present an environmental concern as they are comprised of residual hydrocarbons and metals. Following the hypothesis that endogenous OSPW microbial communities have an enhanced tolerance to heavy metals, we tested the capacity of planktonic and biofilm populations from OSPW to withstand metal ion challenges, using Cupriavidus metallidurans, a known metal-resistant organism, for comparison. The toxicity of the metals toward biofilm and planktonic bacterial populations was determined by measuring the minimum biofilm inhibitory concentrations (MBICs) and planktonic minimum inhibitory concentrations (MICs) using the MBEC ™ assay. We observed that the OSPW community and C. metallidurans had similar tolerances to 22 different metals. While thiophillic elements (Te, Ag, Cd, Ni) were found to be most toxic, the OSPW consortia demonstrated higher tolerance to metals reported in tailings ponds (Al, Fe, Mo, Pb). Metal toxicity correlated with a number of physicochemical characteristics of the metals. Parameters reflecting metal-ligand affinities showed fewer and weaker correlations for the community compared to C. metallidurans, suggesting that the OSPW consortia may have developed tolerance mechanisms toward metals present in their environment. PMID:26849649

  3. Rs-Based Water Resources Inventory of the Philippines: Capacity Building Efforts for Nationwide Implementation

    NASA Astrophysics Data System (ADS)

    Perez, A. M. C.; De La Cruz, R. M.; Olfindo, N. T.; Borlongan, N. J. B.; Felicen, M. M.; Blanco, A. C.

    2016-06-01

    Considering that the Philippines is archipelagic in nature and is exposed to disasters accentuated by climate change, water resource monitoring and management has been an important concern in the country. The design and implementation of an effective management scheme relies heavily on accurate, complete, and updated water resource inventories, usually in the form of maps and geodatabases. With the aim of developing a detailed and comprehensive database of all water resources in the Philippines, a 3-year project entitled "Development of the Philippine Hydrologic Dataset (PHD) for Watersheds from LiDAR Surveys", has been initiated by the University of the Philippines Diliman (UPD) and the Department of Science and Technology (DOST). Various workflows has been developed to extract inland hydrologic features in the Philippines using accurate Light Detection and Ranging (LiDAR) Digital Terrain Models (DTMs) and LiDAR point cloud data obtained through other government-funded programs, supplemented with other remotely-sensed imageries and ancillary information. Since the project covers national-scale mapping and inventory, the implementation was structured to be a collaborative effort between fifteen (15) State Universities/Colleges (SUCs) and Higher Education Institutes (HEIs), along with multiple National Government Agencies (NGAs) and Local Government Units (LGUs). This paper presents the project's general structure, focusing mainly on its attempts and accomplishments in strengthening individual capacities of all involved SUCs, HEIs, and stakeholders utilizing hydrologic data for different applications.

  4. Ground-state ammonia and water in absorption towards Sgr B2

    NASA Astrophysics Data System (ADS)

    Wirström, E. S.; Bergman, P.; Black, J. H.; Hjalmarson, Å.; Larsson, B.; Olofsson, A. O. H.; Encrenaz, P. J.; Falgarone, E.; Frisk, U.; Olberg, M.; Sandqvist, Aa.

    2010-11-01

    Context. Observations of transitions to the ground-state of a molecule are essential to obtain a complete picture of its excitation and chemistry in the interstellar medium, especially in diffuse and/or cold environments. For the important interstellar molecules H2O and NH3, these ground-state transitions are heavily absorbed by the terrestrial atmosphere, hence not observable from the ground. Aims: We attempt to understand the chemistry of nitrogen, oxygen, and their important molecular forms, NH3 and H2O in the interstellar medium of the Galaxy. Methods: We have used the Odin* submillimetre-wave satellite telescope to observe the ground state transitions of ortho-ammonia and ortho-water, including their 15N, 18O, and 17O isotopologues, towards Sgr B2. The extensive simultaneous velocity coverage of the observations, >500 km s-1, ensures that we can probe the conditions of both the warm, dense gas of the molecular cloud Sgr B2 near the Galactic centre, and the more diffuse gas in the Galactic disk clouds along the line-of-sight. Results: We present ground-state NH3 absorption in seven distinct velocity features along the line-of-sight towards Sgr B2. We find a nearly linear correlation between the column densities of NH3 and CS, and a square-root relation to N2H+. The ammonia abundance in these diffuse Galactic disk clouds is estimated to be about 0.5-1 × 10-8, similar to that observed for diffuse clouds in the outer Galaxy. On the basis of the detection of H_218O absorption in the 3 kpc arm, and the absence of such a feature in the H_217O spectrum, we conclude that the water abundance is around 10-7, compared to ~10-8 for NH3. The Sgr B2 molecular cloud itself is seen in absorption in NH3, 15NH3, H2O, H_218O, and H_217O, with emission superimposed on the absorption in the main isotopologues. The non-LTE excitation of NH3 in the environment of Sgr B2 can be explained without invoking an unusually hot (500 K) molecular layer. A hot layer is similarly not required

  5. Influence of the inherent properties of drinking water treatment residuals on their phosphorus adsorption capacities.

    PubMed

    Bai, Leilei; Wang, Changhui; He, Liansheng; Pei, Yuansheng

    2014-12-01

    Batch experiments were conducted to investigate the phosphorus (P) adsorption and desorption on five drinking water treatment residuals (WTRs) collected from different regions in China. The physical and chemical characteristics of the five WTRs were determined. Combined with rotated principal component analysis, multiple regression analysis was used to analyze the relationship between the inherent properties of the WTRs and their P adsorption capacities. The results showed that the maximum P adsorption capacities of the five WTRs calculated using the Langmuir isotherm ranged from 4.17 to 8.20mg/g at a pH of 7 and further increased with a decrease in pH. The statistical analysis revealed that a factor related to Al and 200 mmol/L oxalate-extractable Al (Alox) accounted for 36.5% of the variations in the P adsorption. A similar portion (28.5%) was attributed to an integrated factor related to the pH, Fe, 200 mmol/L oxalate-extractable Fe (Feox), surface area and organic matter (OM) of the WTRs. However, factors related to other properties (Ca, P and 5 mmol/L oxalate-extractable Fe and Al) were rejected. In addition, the quantity of P desorption was limited and had a significant negative correlation with the (Feox+Alox) of the WTRs (p<0.05). Overall, WTRs with high contents of Alox, Feox and OM as well as large surface areas were proposed to be the best choice for P adsorption in practical applications.

  6. Carbon sequestration capacity of sediments, algae, and zooplankton from fresh water aquaculture ponds.

    PubMed

    Anikuttan, K K; Adhikari, S; Kavitha, M; Jayasankar, P

    2016-07-01

    The contribution of aquaculture and allied activities to the emission of green house gases and consequently to global warming is an emerging concern among environmentalists in the recent past. However, there exists ample scope for aquaculture activities to sequester carbon and thus compensate for the carbon emissions linked to aquaculture. This article attempts to elucidate the carbon sequestration capacity of sediments, algae, and zooplankton from fresh water aquaculture ponds. The percent organic carbon in the pond sediments ranged from 0.39 to 1.31 with an average value of 0.912 ± 0.321 whereas the carbon sequestration capacity ranged from 0.442 to 1.882 MgC/ha (1 Mg = 10(6) g) with an average value of 1.018 ± 0.447 MgC/ha. In the case of zooplankton and algae from pond, the percent organic carbon was 7.688 ± 0.196 and 2.354 ± 0.047, respectively, whereas the total estimated carbon burial rate was 0.009 ± 0.005 and 0.150 ± 0.003 MgC/ha, respectively. These findings are discussed with the previous reports available at present and are found to be in comparable ranges.

  7. Water-borne pharmaceuticals reduce phenotypic diversity and response capacity of natural phytoplankton communities

    PubMed Central

    Jokela, Jukka; Castiglioni, Sara; Thomas, Mridul K.; Nizzetto, Luca

    2017-01-01

    Chemical micropollutants occur worldwide in the environment at low concentrations and in complex mixtures, and how they affect the ecology of natural systems is still uncertain. Dynamics of natural communities are driven by the interaction between individual organisms and their growth environment, which is mediated by the organisms’ expressed phenotypic traits. We tested whether exposure to a mixture of 12 pharmaceuticals and personal care products (PPCP) influences phenotypic trait diversity in lake phytoplankton communities and their ability to regulate biomass production to fit environmental changes (response capacity). We exposed natural phytoplankton assemblages to three mixture levels in permeable microcosms maintained at three depths in a eutrophic lake for one week, during which the environmental conditions were fluctuating. We studied individual-level traits, phenotypic diversity and community biomass. PPCP reduced individual-level trait variance and overall community phenotypic diversity, but maintained higher standing phytoplankton biomass compared to untreated controls. Estimated effect sizes of PPCP on traits and community properties were very large (partial Eta-squared > 0.15). The PPCP mixture antagonistically interacted with the natural environmental gradient in habitats offered by different depths and, at concentrations comparable to those in waste-water effluents, prevented communities from converging to the same phenotypic structure and total biomass of unexposed controls. We show that micropollutants can alter individual-level trait diversity of lake phytoplankton communities and therefore their capacity to respond to natural environmental gradients, potentially affecting aquatic ecosystem processes. PMID:28328933

  8. The Near Infrared Absorption Spectrum of Water by CRDS Between 1.26-1.70 µm:Complete Empirical Line List and Continuum Absorption

    NASA Astrophysics Data System (ADS)

    Mondelain, Didier; Campargue, Alain; Kassi, Samir; Mikhailenko, Semen

    2014-06-01

    Due to the increasing performances of Airborne- and ground-based spectrometers, a more and more accurate characterization of the water vapor absorption is required. This is especially true in the transparency windows, corresponding to low absorption spectral regions widely used for probing the Earth's atmosphere. State-of-the-art experimental developments are required to fulfill the needs in terms of accuracy of the spectroscopic data. For that purpose, we are using high-sensitivity Continuous Wave Cavity Ring Down Spectroscopy (CW-CRDS) allowing reproducing in laboratory conditions comparable to the atmospheric ones in terms of absorption path length (tens of kilometers), temperature and pressure. From extensive analysis of our CRDS spectra, we have constructed an empirical line list for "natural" water vapor at 296 K in the 5850 7920 cm-1 region including 38 318 transitions of four major water isotopologues (H2 16O, H218O, H217O and HD16O) with an intensity cut-off of 1·10-29 cm/molecule. The list is made mostly complete over the whole spectral region by including a large number of unobserved weak lines with positions calculated using experimentally determined energy levels and intensities obtained from variational calculations. In addition, we provide HD18O and HD 17O lists in the same region for transitions with intensities larger than 1·10-29 cm/molecule. The HD18O and HD17O lists (1 972 lines in total) were obtained using empirical energy levels available in the literature and variational intensities. The global list (40 290 transitions) including the contribution of the six major isotopologues has been adopted for the new edition of the GEISA database in the region. The advantages and drawbacks of our list will be discussed in comparison with the list provided for the same region in the 2012 edition of the HITRAN database. Separate experiments were dedicated to the measurement of the water vapor self-continuum crosssections in the 1.6 µm window by CW

  9. The influence of water vapor on atmospheric exchange measurements with an ICOS* based Laser absorption analyzer

    NASA Astrophysics Data System (ADS)

    Bunk, Rüdiger; Quan, Zhi; Wandel, Matthias; Yi, Zhigang; Bozem, Heiko; Kesselmeier, Jürgen

    2014-05-01

    Carbonyl sulfide and carbon monoxide are both atmospheric trace gases of high interest. Recent advances in the field of spectroscopy have enabled instruments that measure the concentration of the above and other trace gases very fast and with good precision. Increasing the effective path length by reflecting the light between two mirrors in a cavity, these instruments reach impressive sensitivities. Often it is possible to measure the concentration of more than one trace gas at the same time. The OCS/CO2 Analyzer by LGR (Los Gatos Research, Inc.) measures the concentration of water vapor [H2O], carbonyl sulfide [COS], carbon dioxide [CO2] and carbon monoxide [CO] simultaneously. For that the cavity is saturated with light, than the attenuation of light is measured as in standard absorption spectroscopy. The instrument proved to be very fast with good precision and to be able to detect even very low concentrations, especially for COS (as low as 30ppt in the case of COS). However, we observed a rather strong cross sensitivity to water vapor. Altering the water vapor content of the sampled air with two different methods led to a change in the perceived concentration of COS, CO and CO2. This proved especially problematic for enclosure (cuvette) measurements, where the concentrations of one of the above species in an empty cuvette are compared to the concentration of another cuvette containing a plant whose exchange of trace gases with the atmosphere is of interest. There, the plants transpiration leads to a large difference in water vapor content between the cuvettes and that in turn produces artifacts in the concentration differences between the cuvettes for the other above mentioned trace gases. For CO, simultaneous measurement with a UV-Emission Analyzer (AL 5002, Aerolaser) and the COS/CO Analyzer showed good agreement of perceived concentrations as long as the sample gas was dry and an increasing difference in perceived concentration when the sample gas was

  10. Differential absorption lidar measurements of atmospheric water vapor using a pseudonoise code modulated AlGaAs laser. Thesis

    NASA Technical Reports Server (NTRS)

    Rall, Jonathan A. R.

    1994-01-01

    Lidar measurements using pseudonoise code modulated AlGaAs lasers are reported. Horizontal path lidar measurements were made at night to terrestrial targets at ranges of 5 and 13 km with 35 mW of average power and integration times of one second. Cloud and aerosol lidar measurements were made to thin cirrus clouds at 13 km altitude with Rayleigh (molecular) backscatter evident up to 9 km. Average transmitter power was 35 mW and measurement integration time was 20 minutes. An AlGaAs laser was used to characterize spectral properties of water vapor absorption lines at 811.617, 816.024, and 815.769 nm in a multipass absorption cell using derivative spectroscopy techniques. Frequency locking of an AlGaAs laser to a water vapor absorption line was achieved with a laser center frequency stability measured to better than one-fifth of the water vapor Doppler linewidth over several minutes. Differential absorption lidar measurements of atmospheric water vapor were made in both integrated path and range-resolved modes using an externally modulated AlGaAs laser. Mean water vapor number density was estimated from both integrated path and range-resolved DIAL measurements and agreed with measured humidity values to within 6.5 percent and 20 percent, respectively. Error sources were identified and their effects on estimates of water vapor number density calculated.

  11. The room temperature annealing peak in ionomers: Ionic crystallites or water absorption

    SciTech Connect

    Goddard, R.J.; Grady, B.P.; Cooper, S.L. . Dept. of Chemical Engineering)

    1994-03-28

    A quaternized diol, 3-(trimethylammonio)-1,2-propanediol neutralized with either bromine or iodine, was used to produce a polyurethane cationomer with a poly(tetramethylene oxide) soft segment and a 4,4[prime]-diphenylmethane diisocyanate hard segment. If those cationomers were annealed at room temperature for a period of approximately 1 month in a desiccator filled with dry CaSO[sub 4], differential scanning calorimetry (DSC) studies showed an endotherm centered near 70 C which was not present in the unannealed polymer and did not reappear upon subsequent cooling and heating cycles in the DSC. Some authors have suggested that a very similar endotherm found in other ionomers, most notably ethylene-methacrylic acid (E-MAA) copolymer ionomers, was due to an order-disorder transition within the ionic aggregates, i.e. ionic crystallite melting. In order to isolate the origin of this endotherm, the local environment around the anion in compression molded bromine neutralized samples was measured using the extended X-ray absorption fine-structure (EXAFS) technique. By measuring the change in the local environment over the temperature range corresponding to the DSC endotherm, it has been shown that this endotherm corresponds to water leaving the bromine coordination shell, rather than ionic crystallite melting. Other studies which include thoroughly drying the material in a vacuum oven below the transition temperature to remove the water suggest that the endotherm is due to the energetic change associated with water leaving the coordination environment of the anion in combination with water vaporization.

  12. Atmospheric-water absorption features near 2.2 micrometers and their importance in high spectral resolution remote sensing

    NASA Technical Reports Server (NTRS)

    Kruse, F. A.; Clark, R. N.

    1986-01-01

    Selective absorption of electromagnetic radiation by atmospheric gases and water vapor is an accepted fact in terrestrial remote sensing. Until recently, only a general knowledge of atmospheric effects was required for analysis of remote sensing data; however, with the advent of high spectral resolution imaging devices, detailed knowledge of atmospheric absorption bands has become increasingly important for accurate analysis. Detailed study of high spectral resolution aircraft data at the U.S. Geological Survey has disclosed narrow absorption features centered at approximately 2.17 and 2.20 micrometers not caused by surface mineralogy. Published atmospheric transmission spectra and atmospheric spectra derived using the LOWTRAN-5 computer model indicate that these absorption features are probably water vapor. Spectral modeling indicates that the effects of atmospheric absorption in this region are most pronounced in spectrally flat materials with only weak absorption bands. Without correction and detailed knowledge of the atmospheric effects, accurate mapping of surface mineralogy (particularly at low mineral concentrations) is not possible.

  13. Compressional Wave Speed and Absorption Measurements in a Saturated Kaolinite-Water Artificial Sediment.

    DTIC Science & Technology

    OCEAN BOTTOM, ULTRASONIC PROPERTIES), (*UNDERWATER SOUND, SOUND TRANSMISSION), KAOLINITE , ABSORPTION, COMPRESSIVE PROPERTIES, POROSITY, VELOCITY, VISCOELASTICITY, MATHEMATICAL MODELS, THESES, SEDIMENTATION

  14. Effect of a Disintegration Mechanism on Wetting, Water Absorption, and Disintegration Time of Orodispersible Tablets

    PubMed Central

    Pabari, RM; Ramtoola, Z

    2012-01-01

    The aim of this study was to evaluate the influence of disintegration mechanism of various types of disintegrants on the absorption ratio (AR), wetting time (WT), and disintegration time (DT) of orodispersible tablets (ODTs). ODTs were prepared by direct compression using mannitol as filler and disintegrants selected from a range of swellable, osmotic, and porous disintegrants. Tablets formed were characterized for their water AR, WT, and DT. The porosity and mechanical strength of the tablets were also measured. Results show that the DT of formulated ODTs was directly related to the WT and was a function of the disintegration mechanism of the disintegrant used. The lowest WT and DT were observed for tablets formulated using the osmotic disintegrant sodium citrate and these tablets also showed the lowest AR and porosity. The wetting and disintegration of tablets containing the highly swellable disintegrant, sodium starch glycollate, was slowest despite their high water AR and high tablet porosity. Rapid wetting and disintegration of ODTs were therefore not necessarily related to the porosity of the tablets. PMID:23112534

  15. Effect of a disintegration mechanism on wetting, water absorption, and disintegration time of orodispersible tablets.

    PubMed

    Pabari, Rm; Ramtoola, Z

    2012-07-01

    The aim of this study was to evaluate the influence of disintegration mechanism of various types of disintegrants on the absorption ratio (AR), wetting time (WT), and disintegration time (DT) of orodispersible tablets (ODTs). ODTs were prepared by direct compression using mannitol as filler and disintegrants selected from a range of swellable, osmotic, and porous disintegrants. Tablets formed were characterized for their water AR, WT, and DT. The porosity and mechanical strength of the tablets were also measured. Results show that the DT of formulated ODTs was directly related to the WT and was a function of the disintegration mechanism of the disintegrant used. The lowest WT and DT were observed for tablets formulated using the osmotic disintegrant sodium citrate and these tablets also showed the lowest AR and porosity. The wetting and disintegration of tablets containing the highly swellable disintegrant, sodium starch glycollate, was slowest despite their high water AR and high tablet porosity. Rapid wetting and disintegration of ODTs were therefore not necessarily related to the porosity of the tablets.

  16. Simultaneous enhancements in photon absorption and charge transport of bismuth vanadate photoanodes for solar water splitting

    NASA Astrophysics Data System (ADS)

    Kim, Tae Woo; Ping, Yuan; Galli, Giulia A.; Choi, Kyoung-Shin

    2015-10-01

    n-Type bismuth vanadate has been identified as one of the most promising photoanodes for use in a water-splitting photoelectrochemical cell. The major limitation of BiVO4 is its relatively wide bandgap (~2.5 eV), which fundamentally limits its solar-to-hydrogen conversion efficiency. Here we show that annealing nanoporous bismuth vanadate electrodes at 350 °C under nitrogen flow can result in nitrogen doping and generation of oxygen vacancies. This gentle nitrogen treatment not only effectively reduces the bandgap by ~0.2 eV but also increases the majority carrier density and mobility, enhancing electron-hole separation. The effect of nitrogen incorporation and oxygen vacancies on the electronic band structure and charge transport of bismuth vanadate are systematically elucidated by ab initio calculations. Owing to simultaneous enhancements in photon absorption and charge transport, the applied bias photon-to-current efficiency of nitrogen-treated BiVO4 for solar water splitting exceeds 2%, a record for a single oxide photon absorber, to the best of our knowledge.

  17. Simultaneous enhancements in photon absorption and charge transport of bismuth vanadate photoanodes for solar water splitting.

    PubMed

    Kim, Tae Woo; Ping, Yuan; Galli, Giulia A; Choi, Kyoung-Shin

    2015-10-26

    n-Type bismuth vanadate has been identified as one of the most promising photoanodes for use in a water-splitting photoelectrochemical cell. The major limitation of BiVO4 is its relatively wide bandgap (∼2.5 eV), which fundamentally limits its solar-to-hydrogen conversion efficiency. Here we show that annealing nanoporous bismuth vanadate electrodes at 350 °C under nitrogen flow can result in nitrogen doping and generation of oxygen vacancies. This gentle nitrogen treatment not only effectively reduces the bandgap by ∼0.2 eV but also increases the majority carrier density and mobility, enhancing electron-hole separation. The effect of nitrogen incorporation and oxygen vacancies on the electronic band structure and charge transport of bismuth vanadate are systematically elucidated by ab initio calculations. Owing to simultaneous enhancements in photon absorption and charge transport, the applied bias photon-to-current efficiency of nitrogen-treated BiVO4 for solar water splitting exceeds 2%, a record for a single oxide photon absorber, to the best of our knowledge.

  18. Simultaneous enhancements in photon absorption and charge transport of bismuth vanadate photoanodes for solar water splitting

    PubMed Central

    Kim, Tae Woo; Ping, Yuan; Galli, Giulia A.; Choi, Kyoung-Shin

    2015-01-01

    n-Type bismuth vanadate has been identified as one of the most promising photoanodes for use in a water-splitting photoelectrochemical cell. The major limitation of BiVO4 is its relatively wide bandgap (∼2.5 eV), which fundamentally limits its solar-to-hydrogen conversion efficiency. Here we show that annealing nanoporous bismuth vanadate electrodes at 350 °C under nitrogen flow can result in nitrogen doping and generation of oxygen vacancies. This gentle nitrogen treatment not only effectively reduces the bandgap by ∼0.2 eV but also increases the majority carrier density and mobility, enhancing electron–hole separation. The effect of nitrogen incorporation and oxygen vacancies on the electronic band structure and charge transport of bismuth vanadate are systematically elucidated by ab initio calculations. Owing to simultaneous enhancements in photon absorption and charge transport, the applied bias photon-to-current efficiency of nitrogen-treated BiVO4 for solar water splitting exceeds 2%, a record for a single oxide photon absorber, to the best of our knowledge. PMID:26498984

  19. Arsenic speciation in natural water samples by coprecipitation-hydride generation atomic absorption spectrometry combination.

    PubMed

    Tuzen, Mustafa; Citak, Demirhan; Mendil, Durali; Soylak, Mustafa

    2009-04-15

    A speciation procedure for As(III) and As(V) ions in environmental samples has been presented. As(V) was quantitatively recovered on aluminum hydroxide precipitate. After oxidation of As(III) by using dilute KMnO(4), the developed coprecipitation was applied to determination of total arsenic. Arsenic(III) was calculated as the difference between the total arsenic content and As(V) content. The determination of arsenic levels was performed by hydride generation atomic absorption spectrometry (HG-AAS). The analytical conditions for the quantitative recoveries of As(V) including pH, amount of aluminum as carrier element and sample volume, etc. on the presented coprecipitation system were investigated. The effects of some alkaline, earth alkaline, metal ions and also some anions were also examined. Preconcentration factor was calculated as 25. The detection limits (LOD) based on three times sigma of the blank (N: 21) for As(V) was 0.012 microg L(-1). The satisfactory results for the analysis of arsenic in NIST SRM 2711 Montana soil and LGC 6010 Hard drinking water certified reference materials for the validation of the method was obtained. The presented procedure was successfully applied to real samples including natural waters for arsenic speciation.

  20. Multiplexed selective detection and identification of TCE and xylene in water by on-chip absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Lai, Wei-Cheng; Chakravarty, Swapnajit; Zou, Yi; Chen, Ray T.

    2013-03-01

    We demonstrate a device which can do multiplexed detection of two different chemicals on one chip by using infrared absorption spectroscopy. The signature of Trichloroethylene(TCE) and xylene in water enable multiplexed detection on one chip. We use the slow light effect in the photonic crystal design which enhances the absorption of the analytes by a factor of 30 as demonstrated by our previous works. In order to match the absorption peaks of these two analytes, photonic crystal slow light regions are designed at 1644nm and 1674nm with a SU8 cladding on top. Multiplexed detection is enabled by using a multimode interference (MMI) optical power splitter at the input, which divides optical power into two arms, and Y combiner at the output. Consequently, the absorption of these two chemicals can be enhanced by the slow light effect. The MMI structure and Y combiner also enable the multiplexed detection of two analytes on one chip.

  1. A theoretical investigation of gaseous absorption by water droplets from SO2-HNO3-NH3-CO2-HCl mixtures

    NASA Technical Reports Server (NTRS)

    Adewuyi, Y. G.; Carmichael, G. R.

    1982-01-01

    A physical-chemical model is developed and used to investigate gaseous absorption by water droplets from trace gas mixtures. The model is an extension of that of Carmichael and Peters (1979) and includes the simultaneous absorption of SO2, NH3, HNO3, CO2, and HCl. Gas phase depletion is also considered. Presented results demonstrate that the absorption behavior of raindrops is strongly dependent on drop size, fall distance, trace gas concentrations, and the chemical and physical properties of the constituents of the mixture. In addition, when gas phase depletion is considered, the absorption rates and equilibrium values are also dependent on the precipitation rate itself. Also, the trace constituents liquid phase concentrations may be a factor of six or more lower when gas depletion is considered then when the depletion is ignored. However, the hydrogen ion concentration may be insensitive to the gas phase depletion.

  2. R&D of Absorption Heat Pump System Using New Working Fluid To Utilize Treated Sewage Water

    NASA Astrophysics Data System (ADS)

    Nishiyama, Noriyuki; Fujikura, Kikutaro; Wakimizu, Hiroki; Kaneko, Toshiyuki; Yamazaki, Shiguma; Izu, Masaya

    The absorption heat pump system has been developed to utilized treated sewage water from the view point of environmental protection and energy conservation. The development has two step. Conventional LiBr solution is used at the first step, the new working fluid with higher solubility and lower viscosity is used to imprve the efficiency of absorption heat pump at the second step. The first report says the search for the new working fluid and the performance of absorption heat pump concerned with the second step. LiBr, LiI, LiCl, LiNO3, solution was selected as the new working fluid. The absorption heat pump using the new working fluid was tested and better results were obtained by comparision with LiBr solution.

  3. Color Developing Capacity of Plasma-treated Water as a Source of Nitrite for Meat Curing

    PubMed Central

    Jung, Samooel; Kim, Hyun Joo; Park, Sanghoo; Choe, Jun Ho; Jeon, Hee-Joon; Choe, Wonho

    2015-01-01

    The interaction of plasma with liquid generates nitrogen species including nitrite (NO−2). Therefore, the color developing capacity of plasma-treated water (PTW) as a nitrite source for meat curing was investigated in this study. PTW, which is generated by surface dielectric barrier discharge in air, and the increase of plasma treatment time resulted in increase of nitrite concentration in PTW. The PTW used in this study contains 46 ppm nitrite after plasma treatment for 30 min. To evaluate the effect of PTW on the cured meat color, meat batters were prepared under three different conditions (control, non-cured meat batter; PTW, meat batter cured with PTW; Sodium nitrite, meat batter cured with sodium nitrite). The meat batters were vacuum-packaged and cooked in a water-bath at 80℃ for 30 min. The typical color of cured meat developed in cooked meat batter treated with sodium nitrite or PTW. The lightness (L*) and yellowness (b*) values were similar in all conditions, whereas, the redness (a*) values of cooked meat batter with PTW and sodium nitrite (p<0.05) were significantly higher than the control. These data indicate that PTW can be used as a nitrite source in the curing process of meat without addition of other nitrite sources. PMID:26761900

  4. Multiresidue analysis of pesticides in vegetables and fruits using a high capacity absorbent polymer for water.

    PubMed

    Obana, H; Akutsu, K; Okihashi, M; Kakimoto, S; Hori, S

    1999-08-01

    A single extraction and a single clean-up procedure was developed for multi-residue analysis of pesticides in non-fatty vegetables and fruits. The method involves the use of a high capacity absorbent polymer for water as a drying agent in extraction from wet food samples and of a graphitized carbon column for clean-up. A homogeneously chopped food sample (20 g) and polymer (3 g) were mixed to absorb water from the sample and then 10 min later the mixture was vigorously extracted with ethyl acetate (100 ml). The extract (50 ml), separated by filtration, was loaded on a graphitized carbon column without concentration. Additional ethyl acetate (50 ml) was also eluted and both eluates were concentrated to 5 ml for analysis. The procedure for sample preparation was completed within 2 h. In a recovery test, 107 pesticides were spiked and average recoveries were more than 80% from asparagus, orange, potato and strawberry. Most pesticides were recovered in the range 70-120% with usually less than a 10% RSD for six experiments. The results indicated that a single extraction with ethyl acetate in the presence of polymer can be applied to the monitoring of pesticide residues in foods.

  5. A Preliminary Geomorphological Analysis of Water storage capacity: The Providence Watershed, California

    NASA Astrophysics Data System (ADS)

    Chamorro, A.; Giardino, J. R.; Vitek, J. D.

    2013-12-01

    The Critical Zone of Earth, as defined by NSF in 2007, is series of systems that extend from the top of the canopy to the bottom of the aquifer. The soil system has been used as the primary connection between the various systems. Knowledge of water storage capacity is essential for predicting water availability in the critical zone. Soil depth is one of the most important parameters used to study water storage capacity. Unfortunately, it is challenging to obtain an accurate representation of the degree of spatial variability of soil depth in a watershed. To obtain this data requires extensive and expensive surveys, which can be compounded in forested regions. We make the assumption that soil depth is a function of surface and subsurface geomorphological processes. The Providence Watershed, which is a Critical Zone Center (CZO) is located in the Southern Sierra Nevada of California. The Providence Watershed is ~ 2.8 km2. The general trend of the watershed is northeast and ranges in elevation from 1,700 m to 2,100 m. The dominant vegetation cover is coniferous. In this area, we compiled indices from LIDAR imagery and compared these to hand-auguring profiles collected along Ground Penetrating Radar (GPR) transects. Auguring profiles exist at a spacing of 123 m. The depths of these profiles varied from 0.5 to 7.0 m. We correlated the auguring data with nine indices. None of the correlations, which ranged from -0.50 to 0.21 (Pearson product-moment), were strong. The most significant finding of this study strengthens the important role that GPR can provide to capture the spatial heterogeneity present. GPR lines complimentary to geomorphological mapping can be used as an approach to obtain more accurate results in soil depth and bedrock topography mapping. The appropriate scale of work, however, depends on the understanding of the scale of processes controlling soil formation and erosion. This work is part of the collaborative effort of the Southern Sierra Critical Zone

  6. Solvent effect on the absorption spectra of coumarin 120 in water: A combined quantum mechanical and molecular mechanical study.

    PubMed

    Sakata, Tetsuya; Kawashima, Yukio; Nakano, Haruyuki

    2011-01-07

    The solvent effect on the absorption spectra of coumarin 120 (C120) in water was studied utilizing the combined quantum mechanical∕molecular mechanical (QM∕MM) method. In molecular dynamics (MD) simulation, a new sampling scheme was introduced to provide enough samples for both solute and solvent molecules to obtain the average physical properties of the molecules in solution. We sampled the structure of the solute and solvent molecules separately. First, we executed a QM∕MM MD simulation, where we sampled the solute molecule in solution. Next, we chose random solute structures from this simulation and performed classical MD simulation for each chosen solute structure with its geometry fixed. This new scheme allowed us to sample the solute molecule quantum mechanically and sample many solvent structures classically. Excitation energy calculations using the selected samples were carried out by the generalized multiconfigurational perturbation theory. We succeeded in constructing the absorption spectra and realizing the red shift of the absorption spectra found in polar solvents. To understand the motion of C120 in water, we carried out principal component analysis and found that the motion of the methyl group made the largest contribution and the motion of the amino group the second largest. The solvent effect on the absorption spectrum was studied by decomposing it in two components: the effect from the distortion of the solute molecule and the field effect from the solvent molecules. The solvent effect from the solvent molecules shows large contribution to the solvent shift of the peak of the absorption spectrum, while the solvent effect from the solute molecule shows no contribution. The solvent effect from the solute molecule mainly contributes to the broadening of the absorption spectrum. In the solvent effect, the variation in C-C bond length has the largest contribution on the absorption spectrum from the solute molecule. For the solvent effect on the

  7. Theoretical study of negative thermal expansion in Y2Mo3O12: effect of water absorption

    NASA Astrophysics Data System (ADS)

    Sun, Qiang; Wu, Mingyi; Wang, Lei; Jia, Yu

    2013-03-01

    Y2Mo3O12 exhibits negative thermal expansion (NTE) in a large temperature range (473 ~ 1173 K). However, the material strongly absorb water and form a stable trihydrate structure, where the NTE disappears. Raman spectra revealed that some vibrational modes were missing in the hydrated structure. By DFT calculations, absorption of water in Y2Mo3O12 has been studied. Our results showed that water can strongly absorb in Y2Mo3O12 with O end of the water binding to Y cation, while one hydrogen approaches to the bridge O, which shared by polyhedrons YO6 and MoO4, and forms hydrogen bond. The absorption of water leads the angle of Y-O-Mo reduced, decreasing Y-Mo distance and consequently the volume of the material contracted. Calculated phonon spectra showed that the transverse vibration of Y-O-Mo is restricted due to water absorption. As a result, the NTE, originated from the vibrational mode, is hindered. Our MD simulations also revealed that water can easily diffuse and cross different channels in the material with the aid of Y cations.

  8. Feasibility of tropospheric water vapor profiling using infrared heterodyne differential absorption lidar

    SciTech Connect

    Grund, C.J.; Hardesty, R.M.; Rye, B.J.

    1995-04-03

    Continuous, high quality profiles of water vapor, free of systematic bias, and of moderate temporal and spatial resolution, acquired over long periods at low operational and maintenance cost, are fundamental to the success of the ARM CART program. The development and verification of realistic climate model parameterizations for clouds and net radiation balance, and the correction of other CART site sensor observations for interferences due to the presence of water vapor are critically dependent on water vapor profile measurements. Application of profiles acquired with current techniques, have, to date, been limited by vertical resolution and uniqueness of solution [e.g. high resolution infrared (IR) Fourier transform radiometry], poor spatial and temporal coverage and high operating cost (e.g. radiosondes), or diminished daytime performance, lack of eye-safety, and high maintenance cost (e.g. Raman lidar). Recent developments in infrared laser and detector technology make possible compact IR differential absorption lidar (DIAL) systems at eye-safe wavelengths. In the study reported here, we develop DIAL system performance models and examine the potential of to solve some of the shortcomings of previous methods using parameterizations representative of current technologies. These models are also applied to diagnose and evaluate other strengths and weaknesses unique to the DIAL method for this application. This work is to continue in the direction of evaluating yet smaller and lower-cost laser diode-based systems for routine monitoring of the lower altitudes using photon counting detection methods. We regard the present report as interim in nature and will update and extend it as a final report at the end of the term of the contract.

  9. Seed ultrastructure and water absorption pathway of the root-parasitic plant Phelipanche aegyptiaca (Orobanchaceae)

    PubMed Central

    Joel, Daniel M.; Bar, Hilla; Mayer, Alfred M.; Plakhine, Dina; Ziadne, Hammam; Westwood, James H.; Welbaum, Gregory E.

    2012-01-01

    Background and Aims Obligate root parasitic plants of the Orobanchaceae do not germinate unless they chemically detect a host plant nearby. Members of this family, like Orobanche, Phelipanche and Striga, are noxious weeds that cause heavy damage to agriculture. In spite of their economic impact, only a few light microscopical studies of their minute seeds have been published, and there is no knowledge of their ultrastructure and of the role each tissue plays during the steps preceding germination. This paper describes the ultrastructure of Phelipanche seeds and contributes to our understanding of seed tissue function. Methods Seeds of P. aegyptiaca were examined under light, scanning electron, transmission electron and fluorescence microscopy following various fixations and staining protocols. The results were interpreted with physiological data regarding mode of water absorption and germination stimulation. Key Results and Conclusions The endothelium, which is the inner layer of the testa, rapidly absorbs water. Its interconnected cells are filled with mucilage and contain labyrinthine walls, facilitating water accumulation for germination that starts after receiving germination stimuli. Swelling of the endothelium leads to opening of the micropyle. The perisperm cells underneath this opening mediate between the rhizosphere and the embryo and are likely to be the location for the receptors of germination stimuli. The other perisperm cells are loaded with lipids and protein bodies, as are the endosperm and parts of the embryo. In the endosperm, the oil bodies fuse with each other while they are intact in the embryo and perisperm. Plasmodesmata connect the perisperm cells to each other, and the cells near the micropyle tightly surround the emerging seedling. These perisperm cells, and also the proximal embryo cells, have dense cytoplasmic contents, and they seem to represent the two seed components that are actively involved in transfer of reserve nutrients to the

  10. X-ray absorption spectroscopy as a tool investigating arsenic(III) and arsenic(V) sorption by an aluminum-based drinking-water treatment residual.

    PubMed

    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 <4%. X-ray 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.

  11. Water vapor concentration measurement in singlet oxygen generator by using emission spectroscopy method and absorption at 1392nm

    NASA Astrophysics Data System (ADS)

    Zhao, Weili; Wang, Zengqiang; Fang, Benjie; Li, Qingwei; Jin, Yuqi; Sang, Fengting

    2005-12-01

    By using emission spectroscopy method and absorption at 1392nm, partial water pressure at the exit of a square pipe-array jet-type singlet oxygen generator (SPJSOG) for chemical oxygen-iodine laser (COIL) was measured. The water vapor fraction was calculated from the partial water pressure in the diagnostic cell when we assumed the water vapor fraction in the diagnostic cell is the same as that in the generator. The results from the two methods showed that the water vapor concentration is less than 0.08 in this SPJSOG during normal operation. The water vapor fraction decreases with the increasing of the pressure in the generator and rises with the increasing of buffer gas flow rate and the basic hydrogen peroxide (BHP) temperature in the case of constant chlorine flow rate. Measurements showed that the change of water vapor fraction due to BHP temperature could be ignored during normal operation. It is indicated that the gas flow velocity is the main reason that affects on the water vapor fraction in COIL. It is proved that the emission spectroscopy method is one of the simple and convenient ways to measure the water vapor concentration in singlet oxygen generator (SOG), especially in real time measurements. But absorption spectroscopy method, as a direct measurement, can give the more factual results of the water concentration.

  12. Simulating on water storage and pump capacity of "Kencing" river polder system in Kudus regency, Central Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Wahyudi, Slamet Imam; Adi, Henny Pratiwi; Santoso, Esti; Heikoop, Rick

    2017-03-01

    Settlement in the Jati District, Kudus Regency, Central Java Province, Indonesia, is growing rapidly. Previous paddy fields area turns into new residential, industrial and office buildings. The rain water collected in small Kencing river that flows into big Wulan River. But the current condition, during high rain intensity Wulan river water elevation higher than the Kencing river, so that water can not flow gravity and the area inundated. To reduce the flooding, required polder drainage system by providing a long channel as water storage and pumping water into Wulan river. How to get optimal value of water storage volume, drainage system channels and the pump capacity? The result used to be efficient in the operation and maintenance of the polder system. The purpose of this study is to develop some scenarios water storage volume, water gate operation and to get the optimal value of operational pumps removing water from the Kencing River to Wulan River. Research Method is conducted by some steps. The first step, it is done field orientation in detail, then collecting secondary data including maps and rainfall data. The map is processed into Watershed or catchment area, while the rainfall data is processed into runoff discharge. Furthermore, the team collects primary data by measuring topography to determine the surface and volume of water storage. The analysis conducted to determine of flood discharge, water channel hydraulics, water storage volume and pump capacity corresponding. Based on the simulating of long water storage volume and pump capacity with some scenario trying, it can be determined optimum values. The results used to be guideline in to construction proses, operation and maintenance of the drainage polder system.

  13. Longitudinal dose distribution and energy absorption in PMMA and water cylinders undergoing CT scans

    SciTech Connect

    Li, Xinhua; Zhang, Da; Liu, Bob

    2014-10-15

    Purpose: The knowledge of longitudinal dose distribution provides the most direct view of the accumulated dose in computed tomography (CT) scanning. The purpose of this work was to perform a comprehensive study of dose distribution width and energy absorption with a wide range of subject sizes and beam irradiated lengths. Methods: Cumulative dose distribution along the z-axis was calculated based on the previously published CT dose equilibration data by Li, Zhang, and Liu [Med. Phys. 40, 031903 (10pp.) (2013)] and a mechanism for computing dose on axial lines by Li, Zhang, and Liu [Med. Phys. 39, 5347–5352 (2012)]. Full width at half maximum (FWHM), full width at tenth maximum (FWTM), the total energy (E) absorbed in a small cylinder of unit mass per centimeter square about the central or peripheral axis, and the energy (E{sub in}) absorbed inside irradiated length (L) were subsequently extracted from the dose distribution. Results: Extensive results of FWHM, FWTM, and E{sub in}/E were presented on the central and peripheral axes of infinitely long PMMA (diameters 6–50 cm) and water (diameters 6–55 cm) cylinders with L < 100 cm. FWHM was greater than the primary beam width only on the central axes of large phantoms and also with L ranging from a few centimeter to about 33 cm. FWTM generally increased with phantom diameter, and could be up to 32 cm longer than irradiated length, depending on L, phantom diameter and axis, but was insensitive to phantom material (PMMA or water). E{sub in}/E increased with L and asymptotically approached unity for large L. As phantom diameter increased, E{sub in}/E generally decreased, but asymptotically approached constant levels on the peripheral axes of large phantoms. A heuristic explanation of dose distribution width results was presented. Conclusions: This study enables the reader to gain a comprehensive view of dose distribution width and energy absorption and provides useful data for estimating doses to organs inside or

  14. Sources and light absorption of water-soluble organic carbon aerosols in the outflow from northern China

    NASA Astrophysics Data System (ADS)

    Kirillova, E. N.; Andersson, A.; Han, J.; Lee, M.; Gustafsson, Ö.

    2014-02-01

    High loadings of anthropogenic carbonaceous aerosols in Chinese air influence the air quality for over one billion people and impact the regional climate. A large fraction (17-80%) of this aerosol carbon is water-soluble, promoting cloud formation and thus climate cooling. Recent findings, however, suggest that water-soluble carbonaceous aerosols also absorb sunlight, bringing additional direct and indirect climate warming effects, yet the extent and nature of light absorption by this water-soluble "brown carbon" and its relation to sources is poorly understood. Here, we combine source estimates constrained by dual carbon isotopes with light-absorption measurements of water-soluble organic carbon (WSOC) for a March 2011 campaign at the Korea Climate Observatory at Gosan (KCOG), a receptor station in SE Yellow Sea for the outflow from northern China. The mass absorption cross section at 365 nm (MAC365) of WSOC for air masses from N. China were in general higher (0.8-1.1 m2 g-1), than from other source regions (0.3-0.8 m2 g-1). However, this effect corresponds to only 2-10% of the radiative forcing caused by light absorption by elemental carbon. Radiocarbon constraints show that the WSOC in Chinese outflow had significantly higher fraction fossil sources (30-50%) compared to previous findings in S. Asia, N. America and Europe. Stable carbon (δ13C) measurements were consistent with aging during long-range air mass transport for this large fraction of carbonaceous aerosols.

  15. Influence of polarization of the walnut plywood in the process of preparation on its water and moisture absorption

    NASA Astrophysics Data System (ADS)

    Zamilova, A. F.; Galikhanov, M. F.

    2016-09-01

    This paper demonstrates data on the effect of the polarization on the hygroscopic properties of plywood. The polarization of the plywood using a constant electric field can allow reducing slightly the amount of water and moisture absorption of the plywood material.

  16. Atmospheric Pre-Corrected Differential Absorption Techniques to Retrieve Columnar Water Vapor: Application to AVIRIS 91/95 Data

    NASA Technical Reports Server (NTRS)

    Schlaepfer, Daniel; Borel, Christoph C.; Keller, Johannes; Itten, Klaus I.

    1996-01-01

    Water vapor is one of the main forces for weather development as well as for mesoscale air transport processes. The monitoring of water vapor is therefore an important aim in remote sensing of the atmosphere. Current operational systems for water vapor detection use primarily the emission in the thermal infrared (AVHRR, GOES, ATSR, Meteosat) or in the microwave radiation bands (DMSP). The disadvantage of current satellite systems is either a coarse spatial (horizontal) resolution ranging from one to tens of kilometers or a limited insight into the lower atmosphere. Imaging spectrometry on the other hand measures total column water vapor contents at a high spatial horizontal resolution and has therefore the potential of filling these gaps. The sensors of the AVIRIS instrument are capable of acquiring hyperspectral data in 224 bands located in the visible and near infrared at 10 nm resolution. This data includes the information on constituents of the earth's surface as well as of the atmosphere. The optical measurement of water vapor can be performed using sensor channels located in bands or lines of the absorption spectrum. The AVIRIS sensor has been used to retrieve water vapor and with less accuracy carbon dioxide, oxygen and ozone. To retrieve the water vapor amount, the so called differential absorption technique has been applied. The goal of this technique is to eliminate background factors by taking a ratio between channels within the absorption band and others besides the band. Various ratioing methods on the basis of different channels and calculation techniques were developed. The influence of a trace gas of interest on the radiance at the sensor level is usually simulated by using radiative transfer codes. In this study, the spectral transmittance and radiance are calculated by MODTRAN3 simulations with the new DISORT option. The objective of this work is to test the best performing differential absorption techniques for imaging spectrometry of

  17. Effect of intravenous ranitidine and omeprazole on intestinal absorption of water, sodium, and macronutrients in patients with intestinal resection

    PubMed Central

    Jeppesen, P; Staun, M; Tjellesen, L; Mortensen, P

    1998-01-01

    Background—H2 receptor blockers and proton pump inhibitors reduce intestinal output in patients with short bowel syndrome. 
Aims—To evaluate the effect of intravenous omeprazole and ranitidine on water, electrolyte, macronutrient, and energy absorption in patients with intestinal resection. 
Methods—Thirteen patients with a faecal weight above 1.5 kg/day (range 1.7-5.7 kg/day and a median small bowel length of 100cm were studied. Omeprazole 40 mg twice daily or ranitidine 150mg twice daily were administered for five days in a randomised, double blind, crossover design followed by a three day control period with no treatment. Two patients with a segment of colon in continuation were excluded from analysis which, however, had no influence on the results. 
Results—Omeprazole increased median intestinal wet weight absorption compared with no treatment and ranitidine (p<0.03). The effect of ranitidine was not significant. Four patients with faecal volumes below 2.6 kg/day did not respond to omeprazole; in two absorption increased by 0.5-1 kg/day; and in five absorption increased by 1−2 kg/day. Absorption of sodium, calcium, magnesium, nitrogen, carbohydrate, fat, and total energy was unchanged. Four high responders continued on omeprazole for 12-15 months, but none could be weaned from parenteral nutrition. 
Conclusion—Omeprazole increased water absorption in patients with faecal output above 2.50 kg/day. The effect varied significantly and was greater in patients with a high output, but did not allow parenteral nutrition to be discontinued. Absorption of energy, macronutrients, electrolytes, and divalent cations was not improved. The effect of ranitidine was not significant, possibly because the dose was too low. 

 Keywords: short bowel syndrome; human; diarrhoea; ranitidine; omeprazole PMID:9824602

  18. 3-D water vapor field in the atmospheric boundary layer observed with scanning differential absorption lidar

    NASA Astrophysics Data System (ADS)

    Späth, Florian; Behrendt, Andreas; Muppa, Shravan Kumar; Metzendorf, Simon; Riede, Andrea; Wulfmeyer, Volker

    2016-04-01

    High-resolution three-dimensional (3-D) water vapor data of the atmospheric boundary layer (ABL) are required to improve our understanding of land-atmosphere exchange processes. For this purpose, the scanning differential absorption lidar (DIAL) of the University of Hohenheim (UHOH) was developed as well as new analysis tools and visualization methods. The instrument determines 3-D fields of the atmospheric water vapor number density with a temporal resolution of a few seconds and a spatial resolution of up to a few tens of meters. We present three case studies from two field campaigns. In spring 2013, the UHOH DIAL was operated within the scope of the HD(CP)2 Observational Prototype Experiment (HOPE) in western Germany. HD(CP)2 stands for High Definition of Clouds and Precipitation for advancing Climate Prediction and is a German research initiative. Range-height indicator (RHI) scans of the UHOH DIAL show the water vapor heterogeneity within a range of a few kilometers up to an altitude of 2 km and its impact on the formation of clouds at the top of the ABL. The uncertainty of the measured data was assessed for the first time by extending a technique to scanning data, which was formerly applied to vertical time series. Typically, the accuracy of the DIAL measurements is between 0.5 and 0.8 g m-3 (or < 6 %) within the ABL even during daytime. This allows for performing a RHI scan from the surface to an elevation angle of 90° within 10 min. In summer 2014, the UHOH DIAL participated in the Surface Atmosphere Boundary Layer Exchange (SABLE) campaign in southwestern Germany. Conical volume scans were made which reveal multiple water vapor layers in three dimensions. Differences in their heights in different directions can be attributed to different surface elevation. With low-elevation scans in the surface layer, the humidity profiles and gradients can be related to different land cover such as maize, grassland, and forest as well as different surface layer

  19. Measurement of the Spectral Absorption of Liquid Water in Melting Snow With an Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    Green, Robert O.; Dozier, Jeff

    1995-01-01

    Melting of the snowpack is a critical parameter that drives aspects of the hydrology in regions of the Earth where snow accumulates seasonally. New techniques for measurement of snow melt over regional scales offer the potential to improve monitoring and modeling of snow-driven hydrological processes. In this paper we present the results of measuring the spectral absorption of liquid water in a melting snowpack with the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). AVIRIS data were acquired over Mammoth Mountain, in east central California on 21 May 1994 at 18:35 UTC. The air temperature at 2926 m on Mammoth Mountain at site A was measured at 15-minute intervals during the day preceding the AVIRIS data acquisition. At this elevation. the air temperature did not drop below freezing the night of the May 20 and had risen to 6 degrees Celsius by the time of the overflight on May 21. These temperature conditions support the presence of melting snow at the surface as the AVIRIS data were acquired.

  20. Measurement of the spectral absorption of liquid water in melting snow with an imaging spectrometer

    NASA Technical Reports Server (NTRS)

    Green, Robert O.; Dozier, Jeff

    1995-01-01

    Melting of the snowpack is a critical parameter that drives aspects of the hydrology in regions of the earth where snow accumulates seasonally. New techniques for measurement of snow melt over regional scales offer the potential to improve monitoring and modeling of snow-driven hydrological processes. We present the results of measuring the spectral absorption of liquid water in a melting snowpack with the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). AVIRIS data were acquired over Mammoth Mountain, in east central California on 21 May 1994 at 18:35 UTC. The air temperature at 2926 m on Mammoth Mountain at site A was measured at 15-minute intervals during the day preceding the AVIRIS data acquisition. At this elevation, the air temperature did not drop below freezing the night of May 20 and had risen to 6 degrees Celsius by the time of the overflight on May 21. These temperature conditions support the presence of melting snow at the surface as the AVIRIS data were acquired.

  1. Ex vivo absorption of promestriene from oil-in-water emulsion into infant foreskin.

    PubMed

    Salmon, D; Kassai, B; Roussel, L; Mouriquand, P; Gérard, C; Gorduza, D B; Serre, C; Falson, F; Pivot, C; Pirot, F

    2013-11-01

    Hypospadias is a birth defect in which the urinary tract opening is not at the tip of the penis. Hypospadias surgery is frequently complicated by healing deficiencies. Topical treatments with oestrogens were reported to improve healing. In the present study, ex vivo percutaneous absorption of promestriene, a synthetic oestrogen resulting of the double esterification of estradiol was conducted as a pre-requisite for further clinical trial in infants. Penetration of promestriene into infant foreskin treated with commercial oil in water emulsion (10 μg mg(-1)) for 24 h was characterized showing controlled release properties enabling epidermal concentration more than six times higher than dermal concentration (4.13±2.46 mg g(-1) versus 0.62±0.84 mg g(-1), respectively). Furthermore, apparent promestriene fluxes into and through the skin (i.e., 1.5 μg cm(-2) h(-1) and<0.89 μg cm(-2) h(-1), respectively) were calculated from (i) drug amount retained into epidermis and dermis, or (ii) the limit of detection into the receptor fluid. In conclusion, less than 2% of initial dose were absorbed within 24h which compared well with others steroids applied topically in colloidal systems.

  2. Ultra Narrowband Optical Filters for Water Vapor Differential Absorption Lidar (DIAL) Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Stenholm, Ingrid; DeYoung, Russell J.

    2001-01-01

    Differential absorption lidar (DIAL) systems are being deployed to make vertical profile measurements of atmospheric water vapor from ground and airborne platforms. One goal of this work is to improve the technology of such DIAL systems that they could be deployed on space-based platforms. Since background radiation reduces system performance, it is important to reduce it. One way to reduce it is to narrow the bandwidth of the optical receiver system. However, since the DIAL technique uses two or more wavelengths, in this case separated by 0.1 nm, a fixed-wavelength narrowband filter that would encompass both wavelengths would be broader than required for each line, approximately 0.02 nm. The approach employed in this project is to use a pair of tunable narrowband reflective fiber Bragg gratings. The Bragg gratings are germanium-doped silica core fiber that is exposed to ultraviolet radiation to produce index-of-refraction changes along the length of the fiber. The gratings can be tuned by stretching. The backscattered laser radiation is transmitted through an optical circulator to the gratings, reflected back to the optical circulator by one of the gratings, and then sent to a photodiode. The filter reflectivities were >90 percent, and the overall system efficiency was 30 percent.

  3. Simulation and performance analysis of a 4-effect lithium bromide-water absorption chiller

    SciTech Connect

    Grossman, G.; Zaltash, A.; DeVault, R.C.

    1995-02-01

    Performance simulation has been conducted for a 4-effect lithium bromide-water chiller, capable of substantial performance improvement over state-of-the-art double-effect cycles. The system investigated includes four condensers and four desorbers coupled together, forming an extension of the conventional double-effect cycle; based on prior analytical studies, a parallel flow system was preferred over series flow, and double-condenser coupling was employed, to further improve performance. A modular computer code for simulation of absorption systems (ABSIM) was used to investigate the performances of the cycle. The simulation was carried out to investigate the influence of some major design parameters. A coefficient of performance around 2.0 (cooling) was calculated at the design point, with a heat supply temperature of 600{degrees}F (315{degrees}C) at the solution outlet from the high temperature desorber. With some optimization of the weak (pumped) solution flowrate and of the solution split among the four desorbers, this COP may be raised above 2.2.

  4. Measurements of Water Absorption in the Warm Exo-Uranus GJ 3470b

    NASA Astrophysics Data System (ADS)

    Benneke, Björn; Crossfield, Ian; Knutson, Heather; McCullough, Peter; Lothringer, Joshua; Howard, Andrew; Morley, Caroline; Fortney, Jonathan; Dragomir, Diana; Gilliland, Ron

    2015-12-01

    The discovery of short-period planets with masses and radii intermediate between Earth and Neptune was one of the biggest surprises in the brief history of exoplanet science. These “super-Earths” and “sub-Neptunes” are an order of magnitude more abundant than close-in giant planets. Despite this ubiquity, we know little about their typical compositions and formation histories. Spectroscopic transit observations can shed new light on these mysterious worlds by probing their atmospheric compositions. In this talk, we will give an overview of our ongoing 124-orbit (200-hour) Hubble Space Telescope program to reveal the chemical diversity and formation histories of super-Earths. This unprecedented survey will provide the first comprehensive look at this intriguing new class of planets ranging from 1 Neptune mass and temperatures close to 2000K to a 1 Earth mass planet near the habitable zone of its host star. In this talk, I will discuss the scope of the program and present early science results including measurements of water absorption in the atmosphere of the warm exo-Uranus GJ3470b.

  5. Estimation of canopy water storage capacity from sap flow measurements in a Bornean tropical rainforest

    NASA Astrophysics Data System (ADS)

    Kume, Tomonori; Manfroi, Odair J.; Kuraji, Koichiro; Tanaka, Nobuaki; Horiuchi, Toshinobu; Suzuki, Masakazu; Kumagai, Tomo'omi

    2008-05-01

    SummaryCanopy water storage capacity (Sc) is a key parameter for estimations of rainfall interception using a big-leaf model (BLM). This study proposes a simple method for estimating Sc. The crucial factor in this method is the canopy drying time (or wet canopy duration) after rainfall. The time can be estimated from sap flow measurements in accordance with an earlier study of ours in a Bornean tropical rainforest. By using the estimated canopy drying time to calibrate a BLM for rainfall interception, we derived Sc. This method could also provide aerodynamic resistance (Ra). To validate our estimations, the derived parameters Sc and Ra were compared to Sc and Ra determined independently by a method based on net rainfall measurements on an event basis and on wind profile measurements, respectively. The parameters in our method (Sc = 0.7 mm, Ra = 14 s m-1) were shown to correspond well to the values determined by independent methods. Furthermore, the method proposed in this study is applicable to tropical forests where short canopy drying times can be expected after rainfall; that is, if the cloudy weather after rainfall becomes sunny within 250 min.

  6. Temperature dependences of mechanisms responsible for the water-vapor continuum absorption. I. Far wings of allowed lines.

    PubMed

    Ma, Q; Tipping, R H; Leforestier, C

    2008-03-28

    It is well known that the water-vapor continuum plays an important role in the radiative balance in the Earth's atmosphere. This was first discovered by Elsasser almost 70 years ago, and since that time there has been a large body of work, both experimental and theoretical, on this topic. It has been experimentally shown that for ambient atmospheric conditions, the continuum absorption scales quadratically with the H(2)O number density and has a strong, negative temperature dependence (T dependence). Over the years, there have been three different theoretical mechanisms postulated: Far wings of allowed transitions, water dimers, and collision-induced absorption. Despite the improvements in experimental data, at present there is no consensus on which mechanism is primarily responsible for the absorption. The first mechanism proposed was the accumulation of the far-wing absorption of the strong allowed transitions. Later, absorption by water dimers was proposed and this mechanism provides a qualitative explanation for the strong, negative T dependence. Recently, some atmospheric modelers have proposed that collision-induced absorption is one of the major contributors. However, based on improvements in the theoretical calculation of accurate far-wing line shapes, ab initio dimer calculations, and theoretical collision-induced absorptions, it is now generally accepted that the dominant mechanism for the absorption in the infrared (IR) windows is that due to the far wings. Whether this is true for other spectral regions is not presently established. Although all these three mechanisms have a negative T dependence, their T dependences will be characterized by individual features. To analyze the characteristics of the latter will enable one to assess their roles with more certainty. In this paper, we present a detailed study of the T dependence of the far-wing absorption mechanism. We will then compare our theoretical calculations with the most recent and accurate

  7. A far wing line shape theory and its application to the foreign-broadened water continuum absorption. III

    NASA Technical Reports Server (NTRS)

    Ma, Q.; Tipping, R. H.

    1992-01-01

    The far wing line shape theory developed previously and applied to the calculation of the continuum absorption of pure water vapor is extended to foreign-broadened continua. Explicit results are presented for H2O-N2 and H2O-CO2 in the frequency range from 0 to 10,000/cm. For H2O-N2 the positive and negative resonant frequency average line shape functions and absorption coefficients are computed for a number of temperatures between 296 and 430 K for comparison with available laboratory data. In general the agreement is very good.

  8. Effect of fibre and coupling agent contents on water absorption and flexural modulus of wood fibre polyethylene composites

    NASA Astrophysics Data System (ADS)

    Tissandier, C.; Zhang, Y.; Rodrigue, D.

    2014-05-01

    In two previous studies, wood fiber-reinforced polymer composites (WPC) were prepared via melt processing. In particular, a response surface strategy of a 20 run optimal design for these three factors was adopted. It was found that for these WPC mixing torque, melt viscosity, Young's modulus and tensile stress at break were related to the type of wood used, as well as wood and coupling agent contents. In addition, thermal properties and strain at break were mainly affected by wood and coupling agent contents. Here, a more complete characterization of these WPC under extreme environmental conditions is performed. In particular, the effect of coupling agent content, wood fibre content and wood fibre type on water absorption and flexural modulus are reported under different water immersion time and temperature. The results show that water absorption is influenced by all the parameters studied, while flexural modulus is mainly influenced by wood content and immersion temperature.

  9. PTHrP regulates water absorption and aquaporin expression in the intestine of the marine sea bream (Sparus aurata, L.).

    PubMed

    Carvalho, Edison S M; Gregório, Sílvia F; Canário, Adelino V M; Power, Deborah M; Fuentes, Juan

    2015-03-01

    Water ingestion by drinking is fundamental for ion homeostasis in marine fish. However, the fluid ingested requires processing to allow net water absorption in the intestine. The formation of luminal carbonate aggregates impacts on calcium homeostasis and requires epithelial HCO3(-) secretion to enable water absorption. In light of its endocrine importance in calcium handling and the indication of involvement in HCO3(-) secretion the present study was designed to expose the role of the parathyroid hormone-related protein (PTHrP) in HCO3(-) secretion, water absorption and the regulation of aqp1 gene expression in the anterior intestine of the sea bream. HCO3(-) secretion rapidly decreased when PTHrP(1-34) was added to anterior intestine of the sea bream mounted in Ussing chambers. The effect achieved a maximum inhibition of 60% of basal secretion rates, showing a threshold effective dose of 0.1 ng ml(-1) compatible with reported plasma values of PTHrP. When applied in combination with the adenylate cyclase inhibitor (SQ 22.536, 100 μmol l(-1)) or the phospholipase C inhibitor (U73122, 10 μmol l(-1)) the effect of PTHrP(1-34) on HCO3(-) secretion was reduced by about 50% in both cases. In parallel, bulk water absorption measured in intestinal sacs was sensitive to inhibition by PTHrP. The inhibitory action conforms to a typical dose-response curve in the range of 0.1-1000 ng ml(-1), achieves a maximal effect of 60-65% inhibition from basal rates and shows threshold significant effects at hormone levels of 0.1 ng ml(-1). The action of PTHrP in water absorption was completely abolished in the presence of the adenylate cyclase inhibitor (SQ 22.536, 100 μmol l(-1)) and was insensitive to the phospholipase C inhibitor (U73122, 10 μmol l(-1)). In vivo injections of PTHrP(1-34) or the PTH/PTHrP receptor antagonist PTHrP(7-34) evoked respectively, a significant decrease or increase of aqp1ab, but not aqp1a. Overall the present results suggest that PTHrP acts as a key

  10. The role of water in the performance of biofilters: parameterization of pressure drop and sorption capacities for common packing materials.

    PubMed

    Dorado, Antonio D; Lafuente, Javier; Gabriel, David; Gamisans, Xavier

    2010-08-15

    The presence of water in a biofilter is critical in keeping microorganisms active and abating pollutants. In addition, the amount of water retained in a biofilter may drastically affect the physical properties of packing materials and packed beds. In this study, the influence of water on the pressure drop and sorption capacities of 10 different packing materials were experimentally studied and compared. Pressure drop was characterized as a function of dynamic hold-up, porosity and gas flow rate. Experimental data were fitted to a mathematical expression based on a modified Ergun correlation. Sorption capacities for toluene were determined for both wet and dry materials to obtain information about the nature of interactions between the contaminant, the packing materials and the aqueous phase. The experimental sorption capacities of materials were fitted to different isotherm models for gas adsorption in porous materials. The corresponding confidence interval was determined by the Fisher information matrix. The results quantified the dynamic hold-up effect resulting from the significant increase in the pressure drop throughout the bed, i.e. the financial cost of driving air, and the negative effect of this air on the total amount of hydrophobic pollutant that can be adsorbed by the supports. Furthermore, the results provided equations for ascertaining water presence and sorption capacities that could be widely used in the mathematical modeling of biofilters.

  11. Ultra-high adsorption capacity of zeolitic imidazole framework-67 (ZIF-67) for removal of malachite green from water.

    PubMed

    Lin, Kun-Yi Andrew; Chang, Hsuan-Ang

    2015-11-01

    Zeolitic imidazole frameworks (ZIFs), a new class of adsorbents, are proposed to adsorb Malachite Green (MG) in water. Particularly, ZIF-67 was selected owing to its stability in water and straightforward synthesis. The as-synthesized ZIF-67 was characterized and used to adsorb MG from water. Factors affecting the adsorption capacity were investigated including mixing time, temperature, the presence of salts and pH. The kinetics, adsorption isotherm and thermodynamics of the MG adsorption to ZIF-67 were also studied. The adsorption capacity of ZIF-67 for MG could be as high as 2430mgg(-1) at 20°C, which could be improved at the higher temperatures. Such an ultra-high adsorption capacity of ZIF-67 was almost 10-times of those of conventional adsorbents, including activated carbons and biopolymers. A mechanism for the high adsorption capacity was proposed and possibly attributed to the π-π stacking interaction between MG and ZIF-67. ZIF-67 also could be conveniently regenerated by washing with ethanol and the regeneration efficiency could remain 95% up to 4 cycles of the regeneration. ZIF-67 was also able to remove MG from the aquaculture wastewater, in which MG can be typically found. These features enable ZIF-67 to be one of the most effective and promising adsorbent to remove MG from water.

  12. Laser absorption spectroscopy of water vapor confined in nanoporous alumina: wall collision line broadening and gas diffusion dynamics.

    PubMed

    Svensson, Tomas; Lewander, Märta; Svanberg, Sune

    2010-08-02

    We demonstrate high-resolution tunable diode laser absorption spectroscopy (TDLAS) of water vapor confined in nanoporous alumina. Strong multiple light scattering results in long photon pathlengths (1 m through a 6 mm sample). We report on strong line broadening due to frequent wall collisions (gas-surface interactions). For the water vapor line at 935.685 nm, the HWHM of confined molecules are about 4.3 GHz as compared to 2.9 GHz for free molecules (atmospheric pressure). Gas diffusion is also investigated, and in contrast to molecular oxygen (that moves rapidly in and out of the alumina), the exchange of water vapor is found very slow.

  13. Estimating Dispersivity, Mass Recovery, and Water Hold Up in Field-Scale Leaching Studies by Use of a Capacity Model

    NASA Astrophysics Data System (ADS)

    Young, D. F.; Carleton, J. N.

    2012-12-01

    The USEPA uses field-scale tests (about 1 ha) to evaluate the leaching potential of pesticides used under realistic agricultural conditions. These tests include a bromide tracer to assess the hydrodynamics of the study site. We analyzed 21 of these bromide leaching studies to determine dispersivity, applied tracer mass recovery, and water retention in the vadose zone. Breakthrough curves were generated for various depths (typically 3 to 4 depths at 1-m intervals) at each of the 21 sites as functions of cumulative infiltration, using measured bromide pore water concentrations. Because the field sites were subjected to natural hydrologic conditions (i.e., evaporation, precipitation, and occasional irrigation), the leaching flow rate at each depth was not directly measurable, so leaching rates were estimated using a capacity model driven by measured daily rainfall, evaporation, and temperature. With the leaching rate thus estimated, the first moment of the bromide breakthrough at each depth was determined. Using the first moment, the effective soil-pore water volume was estimated, which allowed the fitting of a one-dimensional advection-dispersion model and optimization of a dispersion coefficient. Results showed indication of an increase in dispersivity with depth (e.g. dispersivity averaged about 10 cm at the 1-m depth, and around 35 cm at the 4-m depth). Peclet numbers ranged from 4 to 40, but averaged about 10 and varied little with depth. Using this method, apparent recovery of applied bromide varied widely from 8% to 250%, with an average of 60% (standard deviation also 60%) indicating the uncertainty involved in estimating breakthrough curves using field-scale data. Apparent water holdup was consistently greater than the reported field capacity, indicating that measured field capacity may provide low estimates of soil water for use in capacity models. It is important to note that the capacity model concept coupled to the advection dispersion model is the USEPA

  14. Water-vapor absorption line measurements in the 940-nm band by using a Raman-shifted dye laser

    NASA Technical Reports Server (NTRS)

    Chu, Zhiping; Wilkerson, Thomas D.; Singh, Upendra N.

    1993-01-01

    We report water-vapor absorption line measurements that are made by using the first Stokes radiation (930-982 nm) with HWHM 0.015/cm generated by a narrow-linewidth, tunable dye laser. Forty-five absorption line strengths are measured with an uncertainty of 6 percent and among them are fourteen strong lines that are compared with previous measurements for the assessment of spectral purity of the light source. Thirty air-broadened linewidths are measured with 8 percent uncertainty at ambient atmospheric pressure with an average of 0.101/cm. The lines are selected for the purpose of temperature-sensitive or temperature-insensitive lidar measurements. Results for these line strengths and linewidths are corrected for broadband radiation and finite laser linewidth broadening effects and compared with the high-resolution transmission molecular absorption.

  15. Water solubilization capacity of mixed reverse micelles: effect of surfactant component, the nature of the oil, and electrolyte concentration.

    PubMed

    Paul, Bidyut K; Mitra, Rajib K

    2005-08-01

    Solubilization of water in mixed reverse micellar systems with anionic surfactant (AOT) and nonionic surfactants (Brijs, Spans, Tweens, Igepal CO 520), cationic surfactant (DDAB)-nonionic surfactants (Brijs, Spans, Igepal CO 520), and nonionic (Igepal CO 520)-nonionics (Brijs, Spans) in oils of different chemical structures and physical properties (isopropyl myristate, isobutyl benzene, cyclohexane) has been studied at 303 K. The enhancement in water solubilization has been evidenced in these systems with some exceptions. The maximum water solubilization capacity (omega(0,max)) in mixed reverse micellar systems occurred at a certain mole fraction of a nonionic surfactant, which is indicated as X(nonionic,max). The addition of electrolyte (NaCl or NaBr) in these systems tends to enhance their solubilization capacities further both at a fixed composition of nonionic (X(nonionic); 0.1) and at X(nonionic,max) at 303 K. The maximum in solubilization capacity of electrolyte (omega(max)) was obtained at an optimal electrolyte concentration (designated as [NaCl](max) or [NaBr](max)). All these parameters, omega(0,max) vis-a-vis X(nonionic,max) and omega(max) vis-a-vis [NaCl](max), have been found to be dependent on the surfactant component (content, EO chains, and configuration of the polar head group, and the hydrocarbon moiety of the nonionic surfactants) and type of oils. The conductance behavior of these systems has also been investigated, focusing on the influences of water content (omega), content of nonionics (X(nonionic)), concentration of electrolyte ([NaCl] or [NaBr]), and oil. Percolation of conductance has been observed in some of these systems and explained by considering the influences of the variables on the rigidity of the oil/water interface and attractive interactions of the surfactant aggregates. Percolation zones have been depicted in the solubilization capacity vs X(nonionic) or [electrolyte] curves in order to correlate with maximum in water or

  16. Collaboration with HEIs: A Key Capacity Building Block for the Uganda Water and Sanitation Public Sector

    ERIC Educational Resources Information Center

    Kayaga, Sam

    2007-01-01

    The capacity of public service staff in developing countries is crucial for achieving the Millennium Development Goals. Literature from developed countries shows that, working with higher education institutions (HEIs), industries have improved their human resource capacity through continuing professional development. This paper reports on research…

  17. The influence of recycled expanded polystyrene (EPS) on concrete properties: Influence on flexural strength, water absorption and shrinkage

    NASA Astrophysics Data System (ADS)

    Elsalah, Jamaleddin; Al-Sahli, Yosra; Akish, Ahmed; Saad, Omar; Hakemi, Abdurrahman

    2013-12-01

    Expanded polystyrene waste in a granular form was used as a lightweight aggregate in order to produce lightweight concretë Lightweight EPS concrete composites were produced by replacing the coarse aggregate, either partially or fully with equal volume of EPS aggregates. The coarse aggregate replacements levels used were 25, 50, 75, and 100%, which corresponded to (9.20, 18.40, 27.60, and 36.8%) from total volume. The investigation is directed towards the development and performance evaluation of the concrete composites containing EPS aggregates, without addition of either bonding additives, or super-plasticizers on some concrete properties such as flexure strength, water absorption and change in length (or shrinkage). Experimental results showed that a density reduction of 12% caused flexure strength to decrease by 25.3% at a replacement level of 25% EPS. However, the reduction percentage strongly depends upon the replacement level of EPS granules. Moreover, the lower strength concretes showed a higher water absorption values compared to higher strength concrete, i.e., increasing the volume percentage of EPS increases the water absorption as well as the negative strain (shrinkage). The negative strain was higher at concretes of lower density (containing a high amount of EPS aggregate). The water to cement ratio of EPS aggregate concrete is found to be slightly lower than that of conventional concrete.

  18. Soluble Fiber with High Water-Binding Capacity, Swelling Capacity, and Fermentability Reduces Food Intake by Promoting Satiety Rather Than Satiation in Rats.

    PubMed

    Tan, Chengquan; Wei, Hongkui; Zhao, Xichen; Xu, Chuanhui; Zhou, Yuanfei; Peng, Jian

    2016-10-02

    To understand whether soluble fiber (SF) with high water-binding capacity (WBC), swelling capacity (SC) and fermentability reduces food intake and whether it does so by promoting satiety or satiation or both, we investigated the effects of different SFs with these properties on the food intake in rats. Thirty-two male Sprague-Dawley rats were randomized to four equal groups and fed the control diet or diet containing 2% konjac flour (KF), pregelatinized waxy maize starch (PWMS) plus guar gum (PG), and PWMS starch plus xanthan gum (PX) for three weeks, with the measured values of SF, WBC, and SC in the four diets following the order of PG > KF > PX > control. Food intake, body weight, meal pattern, behavioral satiety sequence, and short-chain fatty acids (SCFAs) in cecal content were evaluated. KF and PG groups reduced the food intake, mainly due to the decreased feeding behavior and increased satiety, as indicated by decreased meal numbers and increased inter-meal intervals. Additionally, KF and PG groups increased concentrations of acetate acid, propionate acid, and SCFAs in the cecal contents. Our results indicate that SF with high WBC, SC, and fermentability reduces food intake-probably by promoting a feeling of satiety in rats to decrease their feeding behavior.

  19. Soluble Fiber with High Water-Binding Capacity, Swelling Capacity, and Fermentability Reduces Food Intake by Promoting Satiety Rather Than Satiation in Rats

    PubMed Central

    Tan, Chengquan; Wei, Hongkui; Zhao, Xichen; Xu, Chuanhui; Zhou, Yuanfei; Peng, Jian

    2016-01-01

    To understand whether soluble fiber (SF) with high water-binding capacity (WBC), swelling capacity (SC) and fermentability reduces food intake and whether it does so by promoting satiety or satiation or both, we investigated the effects of different SFs with these properties on the food intake in rats. Thirty-two male Sprague-Dawley rats were randomized to four equal groups and fed the control diet or diet containing 2% konjac flour (KF), pregelatinized waxy maize starch (PWMS) plus guar gum (PG), and PWMS starch plus xanthan gum (PX) for three weeks, with the measured values of SF, WBC, and SC in the four diets following the order of PG > KF > PX > control. Food intake, body weight, meal pattern, behavioral satiety sequence, and short-chain fatty acids (SCFAs) in cecal content were evaluated. KF and PG groups reduced the food intake, mainly due to the decreased feeding behavior and increased satiety, as indicated by decreased meal numbers and increased inter-meal intervals. Additionally, KF and PG groups increased concentrations of acetate acid, propionate acid, and SCFAs in the cecal contents. Our results indicate that SF with high WBC, SC, and fermentability reduces food intake—probably by promoting a feeling of satiety in rats to decrease their feeding behavior. PMID:27706095

  20. Role of glucose transporters in the intestinal absorption of gastrodin, a highly water-soluble drug with good oral bioavailability.

    PubMed

    Cai, Zheng; Huang, Juan; Luo, Hui; Lei, Xiaolu; Yang, Zhaoxiang; Mai, Yang; Liu, Zhongqiu

    2013-07-01

    Gastrodin, a sedative drug, is a highly water-soluble phenolic glucoside with poor liposolubility but exhibits good oral bioavailability. The current study aims to investigate whether glucose transporters (GLTs) are involved in the intestinal absorption of gastrodin. The intestinal absorption kinetics of gastrodin was determined using the rat everted gut sac model, the Caco-2 cell culture model and the perfused rat intestinal model. In vivo pharmacokinetic studies using diabetic rats with high GLT expression were performed. Saturable intestinal absorption of gastrodin was observed in rat everted gut sacs. The apparent permeability (Papp) of gastrodin from the apical (A) to basolateral (B) side in Caco-2 cells was two-fold higher than that from B to A. Glucose or phlorizin, a sodium-dependent GLT (SGLT) inhibitor, reduced the absorption rates of gastrodin from perfused rat intestines. In vivo pharmacokinetic studies showed that the time of maximum plasma gastrodin concentration (Tmax) was prolonged from 28 to 72 min when orally co-administered with four times higher dose of glucose. However, the Tmax of gastrodin in diabetic rats was significantly lowered to 20 min because of the high intestinal SGLT1 level. In conclusion, our findings indicate that SGLT1 can facilitate the intestinal absorption of gastrodin.

  1. Radiation effects in water ice: a near-edge x-ray absorption fine structure study.

    PubMed

    Laffon, C; Lacombe, S; Bournel, F; Parent, Ph

    2006-11-28

    The changes in the structure and composition of vapor-deposited ice films irradiated at 20 K with soft x-ray photons (3-900 eV) and their subsequent evolution with temperatures between 20 and 150 K have been investigated by near-edge x-ray absorption fine structure spectroscopy (NEXAFS) at the oxygen K edge. We observe the hydroxyl OH, the atomic oxygen O, and the hydroperoxyl HO(2) radicals, as well as the oxygen O(2) and hydrogen peroxide H(2)O(2) molecules in irradiated porous amorphous solid water (p-ASW) and crystalline (I(cryst)) ice films. The evolution of their concentrations with the temperature indicates that HO(2), O(2), and H(2)O(2) result from a simple step reaction fuelled by OH, where O(2) is a product of HO(2) and HO(2) a product of H(2)O(2). The local order of ice is also modified, whatever the initial structure is. The crystalline ice I(cryst) becomes amorphous. The high-density amorphous phase (I(a)h) of ice is observed after irradiation of the p-ASW film, whose initial structure is the normal low-density form of the amorphous ice (I(a)l). The phase I(a)h is thus peculiar to irradiated ice and does not exist in the as-deposited ice films. A new "very high density" amorphous phase-we call I(a)vh-is obtained after warming at 50 K the irradiated p-ASW ice. This phase is stable up to 90 K and partially transforms into crystalline ice at 150 K.

  2. Trade-offs between water transport capacity and drought resistance in neotropical canopy liana and tree species.

    PubMed

    De Guzman, Mark E; Santiago, Louis S; Schnitzer, Stefan A; Álvarez-Cansino, Leonor

    2016-09-26

    In tropical forest canopies, it is critical for upper shoots to efficiently provide water to leaves for physiological function while safely preventing loss of hydraulic conductivity due to cavitation during periods of soil water deficit or high evaporative demand. We compared hydraulic physiology of upper canopy trees and lianas in a seasonally dry tropical forest to test whether trade-offs between safety and efficiency of water transport shape differences in hydraulic function between these two major tropical woody growth forms. We found that lianas showed greater maximum stem-specific hydraulic conductivity than trees, but lost hydraulic conductivity at less negative water potentials than trees, resulting in a negative correlation and trade-off between safety and efficiency of water transport. Lianas also exhibited greater diurnal changes in leaf water potential than trees. The magnitude of diurnal water potential change was negatively correlated with sapwood capacitance, indicating that lianas are highly reliant on conducting capability to maintain leaf water status, whereas trees relied more on stored water in stems to maintain leaf water status. Leaf nitrogen concentration was related to maximum leaf-specific hydraulic conductivity only for lianas suggesting that greater water transport capacity is more tied to leaf processes in lianas compared to trees. Our results are consistent with a trade-off between safety and efficiency of water transport and may have implications for increasing liana abundance in neotropical forests.

  3. WVR-GPS comparison measurements and calibration of the 20-32 GHz tropospheric water vapor absorption model.

    SciTech Connect

    Keihm, S. J.; Bar-Server, Y.; Liljegren, J. C.; Environmental Research; NASA

    2002-06-01

    Collocated measurements of opacity (from water vapor radiometer brightness temperatures) and wet path delay (from ground-based tracking of global positioning satellites) are used to constrain the model of atmospheric water vapor absorption in the 20-32 GHz band. A differential approach is presented in which the slope of opacity-versus-wet delay data is used as the absorption model constraint. This technique minimizes the effects of radiometric calibration errors and oxygen model uncertainties in the derivation of a best-fit vapor absorption model. A total of approximately five months of data was obtained from two experiment sites. At the Cloud and Radiation Testbed (CART) site near Lamont, Oklahoma, three independent water vapor radiometers (WVRs) provided near-continuous opacity measurements over the interval July-September 1998. At the NASA/Goldstone tracking station in the California desert two WVRs; obtained opacity data over the September-October 1997 interval. At both sites a Global Positioning Satellite (GPS) receiver and surface barometer obtained the data required for deriving the zenith wet delays over the same time frames. Measured values of the opacity-versus-wet delay slope parameter were obtained at four WVR frequencies (20.7, 22.2, 23.8, and 31.4 GHz) and compared with predictions of four candidate absorption models referenced in the literature. With one exception, all three models provide agreement within 5% of the opacity-versus-wet delay slope measurements at all WVR frequencies at both sites. One model provides agreement for all channels at both sites to the 2-3% level. This absorption model accuracy level represents a significant improvement over that attainable using radiosondes.

  4. Heat capacities of aqueous solutions of sodium hydroxide and water ionization up to 300 °C at 10 MPa

    NASA Astrophysics Data System (ADS)

    Schrödle, Simon; Königsberger, Erich; May, Peter M.; Hefter, Glenn

    2008-07-01

    A commercial (Setaram C80) calorimeter has been modified to measure the heat capacities of highly caustic solutions at temperatures up to 300 °C and pressures up to 20 MPa. The improvements have allowed more accurate determination of the isobaric volumetric heat capacities of chemically aggressive liquids at high temperatures. Test measurements with aqueous solutions of sodium chloride showed a reproducibility of about ±0.1%, with an accuracy of ˜0.3% or better, over the whole temperature range. Heat capacities of aqueous solutions of sodium hydroxide at concentrations from 0.5 to 8 mol/kg were measured at temperatures from 50 to 300 °C and a pressure of 10 MPa. Apparent molar isobaric heat capacities of NaOH(aq) were calculated using densities determined previously for the same solutions by vibrating-tube densimetry. Standard state (infinite dilution) partial molar isobaric heat capacities of NaOH(aq) were obtained by extrapolation using an extended Redlich-Meyer equation. Values of the standard heat capacity change for the ionization of water up to 300 °C were derived by combining the present results with the literature data for HCl(aq) and NaCl(aq).

  5. Research on heat transfer characteristics and cold trap capacity of a water catcher during vacuum pre-cooling

    NASA Astrophysics Data System (ADS)

    Liu, Enhai; Liu, Yin; Wang, Changzhong; Liu, Shiqi

    2017-01-01

    Effect of vacuum pre-cooling process on apples was a complex process of heat and mass transfers. The research is based on the physical properties of apples and their heat and mass transfer mechanisms during vacuum pre-cooling. As for the heat transfer characteristics of a water catcher in vacuum pre-cooling, the research studied the heat transfer mechanism and calculated the cold trap capacity by experimental means, and it cold trap capacity were evaluated to supply references for future research into the practical applications of such vacuum pre-cooling techniques. The results provide a theoretical basis for exploring better pre-cooling process conditions and the design of water catchers. The experimental results show that, when the wall temperature of the water catcher is -5°C, the optimal cold trap capacity is about 90.72g and the required cooling capacity is 210.13W in the vacuum pre-cooling of 201.9g of apples.

  6. Influence of wave and current flow on sediment-carrying capacity and sediment flux at the water-sediment interface.

    PubMed

    Zheng, Jun; Li, Ruijie; Yu, Yonghai; Suo, Anning

    2014-01-01

    In nearshore waters, spatial and temporal scales of waves, tidal currents, and circulation patterns vary greatly. It is, therefore, difficult to combine these factors' effects when trying to predict sediment transport processes. This paper proposes the concept of significant wave velocity, which combines the effects of waves, tides, and ocean currents using the horizontal kinetic energy superposition principle. Through a comparison of the relationship between shear stress at the water-sediment interface and sediment-carrying capacity, assuming equilibrium sediment flux, a new formula for sediment-carrying capacity, which incorporates the concept of significant wave velocities, is derived. Sediment-carrying capacity is a function of the critical velocity, which increases with water depth and decreases with increasing relative roughness of the sea bed. Finally, data from field observation stations and simulations are used to test the proposed formula. The results show that the new formula is in good agreement with both field and simulation data. This new formula for sediment-carrying capacity can be used to simulate nearshore sediment transport.

  7. [Generation of reactive oxygen species in water under exposure of visible or infrared irradiation at absorption band of molecular oxygen].

    PubMed

    Gudkov, S V; Karp, O E; Garmash, S A; Ivanov, V E; Chernikov, A V; Manokhin, A A; Astashev, M E; Iaguzhinskiĭ, L S; Bruskov, V I

    2012-01-01

    It is found that in bidistilled water saturated with oxygen hydrogen peroxide and hydroxyl radicals are formed under the influence of visible and infrared radiation in the absorption bands of molecular oxygen. Formation of reactive oxygen species (ROS) occurs under the influence of both solar and artificial light sourses, including the coherent laser irradiation. The oxygen effect, i.e. the impact of dissolved oxygen concentration on production of hydrogen peroxide induced by light, is detected. It is shown that the visible and infrared radiation in the absorption bands of molecular oxygen leads to the formation of 8-oxoguanine in DNA in vitro. Physicochemical mechanisms of ROS formation in water when exposed to visible and infrared light are studied, and the involvement of singlet oxygen and superoxide anion radicals in this process is shown.

  8. Adding silanes to MMA: the effects on the water absorption, adhesive strength and mechanical properties of acrylic denture base resins.

    PubMed

    Kanie, T; Fujii, K; Arikawa, H; Inoue, K

    2000-12-01

    The adhesive strength of porcelain artificial teeth and polymethylmethacrylates (PMMAs), which contained silanes with various number of vinyl or ethoxy groups, and the mechanical and physical properties of the PMMAs were measured. Four types of PMMAs with silanes showed high adhesive shear strength and caused fractures in the porcelain. Water absorption of the PMMAs increased with the addition of silane, but that of one type with silane was almost the same as the PMMA only type. The flexural strengths of the PMMAs with silane, except for one type, showed no significant differences compared with that of PMMA (p < 0.05). The Tg levels of all PMMAs with silane fell less than that of PMMA. From these results, it was found that PMMA with silane from three vinyl groups and one ethoxy group showed excellent chemical bonding to porcelain and low water absorption.

  9. Multi-epoch Detections of Water Ice Absorption in Edge-on Disks around Herbig Ae Stars: PDS 144N and PDS 453

    NASA Astrophysics Data System (ADS)

    Terada, Hiroshi; Tokunaga, Alan T.

    2017-01-01

    We report the multi-epoch detections of water ice in 2.8–4.2 μ {{m}} spectra of two Herbig Ae stars, PDS 144N (A2 IVe) and PDS 453 (F2 Ve), which have an edge-on circumstellar disk. The detected water ice absorption is found to originate from their protoplanetary disks. The spectra show a relatively shallow absorption of water ice of around 3.1 μ {{m}} for both objects. The optical depths of the water ice absorption are ∼0.1 and ∼0.2 for PDS 144N and PDS 453, respectively. Compared to the water ice previously detected in low-mass young stellar objects with an edge-on disk with a similar inclination angle, these optical depths are significantly lower. It suggests that stronger UV radiation from the central stars effectively decreases the water ice abundance around the Herbig Ae stars through photodesorption. The water ice absorption in PDS 453 shows a possible variation of the feature among the six observing epochs. This variation could be due to a change of absorption materials passing through our line of sight to the central star. The overall profile of the water ice absorption in PDS 453 is quite similar to the absorption previously reported in the edge-on disk object d216-0939, and this unique profile may be seen only at a high inclination angle in the range of 76°–80°.

  10. Assessment of optical path length in tissue using neodymium and water absorptions for application to near-infrared spectroscopy.

    PubMed

    Nighswander-Rempel, Stephen P; Kupriyanov, Valery V; Shaw, R Anthony

    2005-01-01

    Quantitative analysis of blood oxygen saturation using near-IR spectroscopy is made difficult by uncertainties in both the absolute value and the wavelength dependence of the optical path length. We introduce a novel means of assessing the wavelength dependence of path length, exploiting the relative intensities of several absorptions exhibited by an exogenous contrast agent (neodymium). Combined with a previously described method that exploits endogenous water absorptions, the described technique estimates the absolute path length at several wavelengths throughout the visible/near-IR range of interest. Isolated rat hearts (n = 11) are perfused separately with Krebs-Henseleit buffer (KHB) and a KHB solution to which neodymium had been added, and visible/near-IR spectra are acquired using an optical probe made up of emission and collection fibers in concentric rings of diameters 1 and 3 mm, respectively. Relative optical path lengths at 520, 580, 679, 740, 800, 870, and 975 nm are 0.41+/-0.13, 0.49+/-0.21, 0.90+/-0.09, 0.94+/-0.01, 1.00, 0.84+/-0.01, and 0.78+/-0.08, respectively. The absolute path length at 975 nm is estimated to be 3.8+/-0.6 mm, based on the intensity of the water absorptions and the known tissue water concentration. These results are strictly valid only for the experimental geometry applied here.

  11. A comparative study of sodium dodecyl sulfate and freezing/thawing treatment on wheat starch: The role of water absorption.

    PubMed

    Tao, Han; Wang, Pei; Zhang, Bao; Wu, Fengfeng; Jin, Zhengyu; Xu, Xueming

    2016-06-05

    The effect of freezing on functionality of native and sodium dodecyl sulfate (SDS)-treated wheat starches was investigated, with the aim of understanding the role of water absorption during freezing process. SDS is one of most efficient detergents to remove non-starch components (such as proteins and lipids) for starches but does not cause any apparent damage on granular structure. Slow swelling could be converted to rapid swelling by SDS washing, indicating higher water absorption. Freezing process induced slight roughness on starch granules but the non-starch components content was little affected. Combined SDS+freezing treatment significantly decreased both amylose and proteins non-starch components contents, which was accompanied with high gelatinization temperatures, melting enthalpy, and pasting viscosities. A smaller bread specific volume was obtained from SDS+freezing-treated starches while the crumb firmness significantly increased (p<0.05). SDS mainly extracted the surface components from starch granules, leading to high water absorption and making granules sensitive to the freezing treatment.

  12. Ultraviolet-visible absorption spectra of chromophoric dissolved organic matter (CDOM) in waters throughout the Kolyma River basin, East Siberia

    NASA Astrophysics Data System (ADS)

    Frey, K. E.; Bulygina, E. B.; Bunn, A. G.; Chandra, S.; Davydov, S.; Holmes, R. M.; Schade, J. D.; Sobczak, W. V.; Spektor, V. V.; Zimov, S. A.

    2009-12-01

    The Kolyma River in East Siberia is among the six largest Arctic rivers and drains a region underlain by vast deposits of Pleistocene loess known as yedoma, most of which are currently stored in ice-rich permafrost throughout the region. These yedoma deposits are important sources of dissolved organic matter to terrestrial waters that in turn play a significant role in the transport and ultimate mineralization of organic carbon to atmospheric CO2 and CH4. In order to determine the concentrations and characteristics of this dissolved organic matter, we measured the ultraviolet-visible absorption spectra (200-800 nm) of chromophoric dissolved organic matter (CDOM) from a broad collection of waters throughout a ~250 km transect of the northern Kolyma River basin. 124 samples were collected during July 2008 and 2009 and include soil pore waters, lakes, streams, rivers, and the Kolyma River mainstem. Absorbance values are highly positively correlated with dissolved organic carbon concentrations, with the highest values in soil pore waters and lowest values in the Kolyma River mainstem. Spectral slopes (at 275-295 nm and 350-400 nm, calculated within log-transformed absorption spectra) are also used to investigate contrasting water types and are found to be useful indicators of the bioavailability of dissolved organic matter. With ongoing and future permafrost degradation, yedoma deposits throughout the East Siberian region will become more hydrologically active and have the potential to be even greater sources of dissolved organic matter to soil pore waters, lakes, streams, rivers, and ultimately to the Arctic Ocean. As such, the ability to easily and comprehensively monitor the quantity and quality of dissolved organic matter across the landscape through methods such as ultraviolet-visible absorption is becoming critical for understanding the global significance of the Arctic carbon cycle.

  13. Water Resource Management Mechanisms for Intrastate Violent Conflict Resolution: the Capacity Gap and What To Do About It.

    NASA Astrophysics Data System (ADS)

    Workman, M.; Veilleux, J. C.

    2014-12-01

    Violent conflict and issues surrounding available water resources are both global problems and are connected. Violent conflict is increasingly intrastate in nature and coupled with increased hydrological variability as a function of climate change, there will be increased pressures on water resource use. The majority of mechanisms designed to secure water resources are often based on the presence of a governance framework or another type of institutional capacity, such as offered through a supra- or sub-national organization like the United Nations or a river basin organization. However, institutional frameworks are not present or loose functionality during violent conflict. Therefore, it will likely be extremely difficult to secure water resources for a significant proportion of populations in Fragile and Conflict Affected States. However, the capacity in Organisation for Economic Co-operation and Development nations for the appropriate interventions to address this problem is reduced by an increasing reluctance to participate in interventionist operations following a decade of expeditionary warfighting mainly in Iraq and Afghanistan, and related defence cuts. Therefore, future interventions in violent conflict and securing water resources may be more indirect in nature. This paper assesses the state of understanding key areas in the present literature and highlights the gap of securing water resources during violent conflict in the absence of institutional capacity. There is a need to close this gap as a matter of urgency by formulating frameworks to assess the lack of institutional oversight / framework for water resources in areas where violent conflict is prevalent; developing inclusive resource management platforms through transparency and reconciliation mechanisms; and developing endogenous confidence-building measures and evaluate how these may be encouraged by exogenous initiatives including those facilitated by the international community. This effort

  14. Understanding enabling capacities for managing the 'wicked problem' of nonpoint source water pollution in catchments: a conceptual framework.

    PubMed

    Patterson, James J; Smith, Carl; Bellamy, Jennifer

    2013-10-15

    Nonpoint source (NPS) water pollution in catchments is a 'wicked' problem that threatens water quality, water security, ecosystem health and biodiversity, and thus the provision of ecosystem services that support human livelihoods and wellbeing from local to global scales. However, it is a difficult problem to manage because water catchments are linked human and natural systems that are complex, dynamic, multi-actor, and multi-scalar in nature. This in turn raises questions about understanding and influencing change across multiple levels of planning, decision-making and action. A key challenge in practice is enabling implementation of local management action, which can be influenced by a range of factors across multiple levels. This paper reviews and synthesises important 'enabling' capacities that can influence implementation of local management action, and develops a conceptual framework for understanding and analysing these in practice. Important enabling capacities identified include: history and contingency; institutional arrangements; collaboration; engagement; vision and strategy; knowledge building and brokerage; resourcing; entrepreneurship and leadership; and reflection and adaptation. Furthermore, local action is embedded within multi-scalar contexts and therefore, is highly contextual. The findings highlight the need for: (1) a systemic and integrative perspective for understanding and influencing change for managing the wicked problem of NPS water pollution; and (2) 'enabling' social and institutional arenas that support emergent and adaptive management structures, processes and innovations for addressing NPS water pollution in practice. These findings also have wider relevance to other 'wicked' natural resource management issues facing similar implementation challenges.

  15. [Effects of tillage in fallow period on soil water and nitrogen absorption and translocation by wheat plant].

    PubMed

    Ren, Ai-Xia; Sun, Min; Zhao, Wei-Feng; Deng, Lian-Feng; Deng, Yan; Gao, Zhi-Qiang

    2013-12-01

    Field test was carried out to study the effect of tillage in fallow period on soil water before sowing and growth stages, and nitrogen (N) absorption, translocation by wheat plant. The current data showed that tillage in fallow period improved the soil water at the depth of 0-300 cm before sowing and growth stages, especially in dry years. Such tillage significantly improved N accumulation in leaf, stem and sheath (SS) at anthesis, grain N accumulation at maturity, N mobilization in SS and the contribution of mobilized N to grain N, amount of mobilized N in leaf, level of N accumulation before anthesis, N transportation from vegetative organs to grains after anthesis, and nitrogen accumulation after anthesis, which in turn enhanced the efficiency of N uptake. Deep tillage at 45 days after harvest had the best effect. Significant correlations were detected between soil water and N accumulation before anthesis as well as N translation from vegetative organs grains after anthesis, particularly in dry years, while the correlation between soil water from sowing to an thesis and nitrogen accumulation amount after anthesis was significant in wet years, but not in dry years. Tillage in fallow period especially deep tillage after raining could benefit soil water preservation, as well as N absorption and translocation by plant.

  16. Correlation between octanol/water and liposome/water distribution coefficients and drug absorption of a set of pharmacologically active compounds.

    PubMed

    Esteves, Freddy; Moutinho, Carla; Matos, Carla

    2013-06-01

    Absorption and consequent therapeutic action are key issues in the development of new drugs by the pharmaceutical industry. In this sense, different models can be used to simulate biological membranes to predict the absorption of a drug. This work compared the octanol/water and the liposome/water models. The parameters used to relate the two models were the distribution coefficients between liposomes and water and octanol and water and the fraction of drug orally absorbed. For this study, 66 drugs were collected from literature sources and divided into four groups according to charge and ionization degree: neutral; positively charged; negatively charged; and partially ionized/zwitterionic. The results show a satisfactory linear correlation between the octanol and liposome systems for the neutral (R²= 0.9324) and partially ionized compounds (R²= 0.9367), contrary to the positive (R²= 0.4684) and negatively charged compounds (R²= 0.1487). In the case of neutral drugs, results were similar in both models because of the high fraction orally absorbed. However, for the charged drugs (positively, negatively, and partially ionized/zwitterionic), the liposomal model has a more-appropriate correlation with absorption than the octanol model. These results show that the neutral compounds only interact with membranes through hydrophobic bonds, whereas charged drugs favor electrostatic interactions established with the liposomes. With this work, we concluded that liposomes may be a more-appropriate biomembrane model than octanol for charged compounds.

  17. Pathways for building capacity and ensuring effective transboundary water resources management in Africa: Revisiting the key issues, opportunities and challenges

    NASA Astrophysics Data System (ADS)

    Chikozho, Claudious

    The performance of most organizations and institutions set up to facilitate transboundary water resources management in Africa remains unsatisfactory and new frameworks are required to address this performance gap. Using the Nile and Senegal River Basins as case studies, this paper applies qualitative research methods to explore the transboundary river basin management terrain in Africa with a view to identifying and articulating some of the major issues, challenges and opportunities faced in building the capacity of the main actors and institutions in the sector. The paper establishes that the creation of basin management institutions as the assumed panacea to challenges evident in this sector has not delivered the desired results. Some of the institutions established for this purpose in Africa have remained functionally weak and ineffective. Thus, demand for capacity-building interventions in this landscape remains high. The paper concludes that comprehensive capacity-building interventions should seek to improve the competencies and skills of key actors in implementing the broad range of activities constituting integrated water resources management in transboundary basins. In-depth analysis of the fundamental capacity constraints and challenges that key players face in relation to key drivers for cooperation is the absolutely necessary ingredient.

  18. Assessing water resources adaptive capacity to climate change impacts in the Pacific Northwest Region of North America

    NASA Astrophysics Data System (ADS)

    Hamlet, A. F.

    2010-07-01

    Climate change impacts in Pacific Northwest Region of North America (PNW) are projected to include increasing temperatures and changes in the seasonality of precipitation (increasing precipitation in winter, decreasing precipitation in summer). Changes in precipitation are also spatially varying, with the northwestern parts of the region generally experiencing greater increases in cool season precipitation than the southeastern parts. These changes in climate are projected to cause loss of snowpack and associated streamflow timing shifts which will increase cool season (October-March) flows and decrease warm season (April-September) flows and water availability. Hydrologic extremes such as the 100 year flood and extreme low flows are also expected to change, although these impacts are not spatially homogeneous and vary with mid-winter temperatures and other factors. These changes have important implications for natural ecosystems affected by water, and for human systems. The PNW is endowed with extensive water resources infrastructure and well-established and well-funded management agencies responsible for ensuring that water resources objectives (such as water supply, water quality, flood control, hydropower production, environmental services, etc.) are met. Likewise, access to observed hydrological, meteorological, and climatic data and forecasts is in general exceptionally good in the United States and Canada, and access to these products and services is often supported by federally funded programs that ensure that these resources are available to water resources practitioners, policy makers, and the general public. Access to these extensive resources support the argument that at a technical level the PNW has high capacity to deal with the potential impacts of natural climate variability on water resources. To the extent that climate change will manifest itself as moderate changes in variability or extremes, we argue that existing water resources infrastructure

  19. Assessing water resources adaptive capacity to climate change impacts in the Pacific Northwest Region of North America

    NASA Astrophysics Data System (ADS)

    Hamlet, A. F.

    2011-05-01

    Climate change impacts in Pacific Northwest Region of North America (PNW) are projected to include increasing temperatures and changes in the seasonality of precipitation (increasing precipitation in winter, decreasing precipitation in summer). Changes in precipitation are also spatially varying, with the northwestern parts of the region generally experiencing greater increases in cool season precipitation than the southeastern parts. These changes in climate are projected to cause loss of snowpack and associated streamflow timing shifts which will increase cool season (October-March) flows and decrease warm season (April-September) flows and water availability. Hydrologic extremes such as the 100 yr flood and extreme low flows are also expected to change, although these impacts are not spatially homogeneous and vary with mid-winter temperatures and other factors. These changes have important implications for natural ecosystems affected by water, and for human systems. The PNW is endowed with extensive water resources infrastructure and well-established and well-funded management agencies responsible for ensuring that water resources objectives (such as water supply, water quality, flood control, hydropower production, environmental services, etc.) are met. Likewise, access to observed hydrological, meteorological, and climatic data and forecasts is in general exceptionally good in the United States and Canada, and is often supported by federally funded programs that ensure that these resources are freely available to water resources practitioners, policy makers, and the general public. Access to these extensive resources support the argument that at a technical level the PNW has high capacity to deal with the potential impacts of natural climate variability on water resources. To the extent that climate change will manifest itself as moderate changes in variability or extremes, we argue that existing water resources infrastructure and institutional arrangements

  20. Variability in light absorption and scattering of phytoplankton in Patagonian waters: Role of community size structure and pigment composition

    NASA Astrophysics Data System (ADS)

    Ferreira, Amabile; Stramski, Dariusz; Garcia, Carlos A. E.; Garcia, Virginia M. T.; Ciotti, ÁUrea M.; Mendes, Carlos R. B.

    2013-02-01

    Intense phytoplankton blooms were observed along the Patagonian shelf-break with satellite ocean color data, but few in situ optical observations were made in that region. We examine the variability of phytoplankton absorption and particulate scattering coefficients during such blooms on the basis of field data. The chlorophyll-a concentration, [Chla], ranged from 0.1 to 22.3 mg m-3 in surface waters. The size fractionation of [Chla] showed that 80% of samples were dominated by nanophytoplankton (N-group) and 20% by microphytoplankton (M-group). Chlorophyll-specific phytoplankton absorption coefficients at 440 and 676 nm, a*ph(440) and a*ph(676), and particulate scattering coefficient at 660 nm, b*p(660), ranged from 0.018 to 0.173, 0.009 to 0.046, and 0.031 to 2.37 m2 (mg Chla)-1, respectively. Both a*ph(440) and a*ph(676) were statistically higher for the N-group than M-group and also considerably higher than expected from global trends as a function of [Chla]. This result suggests that size of phytoplankton cells in Patagonian waters tends to be smaller than in other regions at similar [Chla]. The phytoplankton cell size parameter, Sf, derived from phytoplankton absorption spectra, proved to be useful for interpreting the variability in the data around the general inverse dependence of a*ph(440), a*ph(676), and b*p(660) on [Chla]. Sf also showed a pattern along the increasing trend of a*ph(440) and a*ph(676) as a function of the ratios of some accessory pigments to [Chla]. Our results suggest that the variability in phytoplankton absorption and scattering coefficients in Patagonian waters is caused primarily by changes in the dominant phytoplankton cell size accompanied by covariation in the concentrations of accessory pigments.

  1. Sources and light absorption of water-soluble brown carbon aerosols in the outflow from northern China

    NASA Astrophysics Data System (ADS)

    Kirillova, E. N.; Andersson, A.; Han, J.; Lee, M.; Gustafsson, Ö.

    2013-07-01

    High loadings of anthropogenic carbonaceous aerosols in Chinese air influence the air quality for over 1 billion people and impact the regional climate. A large fraction (17-80%) of this aerosol carbon is water soluble, promoting cloud formation and thus climate cooling. Recent findings, however, suggest that water-soluble carbonaceous aerosols also absorb sunlight, bringing additional direct and indirect climate warming effects, yet the extent and nature of light absorption by this water-soluble brown carbon (WS-BrC) and its relation to sources is poorly understood. Here, we combine source estimates constrained by dual-carbon-isotope with light absorption measurements of WS-BrC for a March 2011 campaign at the Korea Climate Observatory at Gosan (KCOG), a receptor station in SE Yellow Sea for the outflow from N. China. The mass absorption cross-section (MAC) of WS-BrC for air masses from N. China were in general higher (0.8-1.1 m2 g-1), than from other source regions (0.3-0.8 m2 g-1). We estimate that this effect corresponds to 13-49% of the radiative forcing caused by light absorption by black carbon. Radiocarbon constraints show that the WS-BrC in Chinese outflow had significantly higher amounts of fossil sources (30-50%) compared to previous findings in S. Asia, N. America and Europe. Stable carbon (δ13C) measurements indicated influence of aging during air mass transport. These results indicate the importance of incorporating WS-BrC in climate models and the need to constrain climate effects by emission source sector.

  2. Progress toward a water-vapor differential absorption lidar (DIAL) using a widely tunable amplified diode laser source

    NASA Astrophysics Data System (ADS)

    Obland, Michael D.; Meng, Lei S.; Repasky, Kevin S.; Shaw, Joseph A.; Carlsten, John L.

    2005-08-01

    Water vapor is one of the most significant constituents of the atmosphere because of its role in cloud formation, precipitation, and interactions with electromagnetic radiation, especially its absorption of longwave infrared radiation. Some details of the role of water vapor and related feedback mechanisms in the Earth system need to be characteriz