WorldWideScience

Sample records for bisulfates

  1. FT-IR TRANSMISSION SPECTROSCOPY FOR QUANTITATION OF AMMONIUM BISULFATE IN FINE PARTICULATE MATTER COLLECTED ON TEFLON FILTERS

    Science.gov (United States)

    A quantitative measurement method for fine particle bisulfatein ammonium bisulfate collected from the ambient air onto Teflon filters is described. nfrared absorbance measurements of the Teflon filters are made before and after particle collection. ubtraction of the two spectra r...

  2. Andrographolide Sodium Bisulfate Prevents UV-Induced Skin Photoaging through Inhibiting Oxidative Stress and Inflammation

    OpenAIRE

    Janis Ya-Xian Zhan; Xiu-Fen Wang; Yu-Hong Liu; Zhen-Biao Zhang; Lan Wang; Jian-Nan Chen; Song Huang; Hui-Fang Zeng; Xiao-Ping Lai

    2016-01-01

    Andrographolide sodium bisulfate (ASB), a water-soluble form made from andrographolide through sulfonating reaction, is an antioxidant and anti-inflammatory drug; however, the antiphotoaging effect of ASB has still not been revealed. Oxidative stress and inflammation are known to be responsible for ultraviolet (UV) irradiation induced skin damage and consequently premature aging. In this study, we aimed at examining the effect of ASB on UV-induced skin photoaging of mice by physiological and ...

  3. Reducing Ammonia Volatilization and Escherichia coli from Broiler Litter Using Multiple Applications of Sodium Bisulfate

    OpenAIRE

    Hunolt, Alicia Erin

    2015-01-01

    Ammonia (NH3) emissions from animal manure, such as poultry litter, can cause air quality problems. These emissions also result in excessive nitrogen (N) loading into aquatic environments which can lead to water quality problems where N is the limiting nutrient for eutrophication, such as the Chesapeake Bay. Poultry litter treatment (PLT, sodium bisulfate) is an acidic amendment that is applied to litter in poultry houses to decrease NH3 emissions, but currently it can only be ...

  4. Relative Order of Sulfuric Acid, Bisulfate, Hydronium, and Cations at the Air-Water Interface.

    Science.gov (United States)

    Hua, Wei; Verreault, Dominique; Allen, Heather C

    2015-11-01

    Sulfuric acid (H2SO4), bisulfate (HSO4(-)), and sulfate (SO4(2-)) are among the most abundant species in tropospheric and stratospheric aerosols due to high levels of atmospheric SO2 emitted from biomass burning and volcanic eruptions. The air/aqueous interfaces of sulfuric acid and bisulfate solutions play key roles in heterogeneous reactions, acid rain, radiative balance, and polar stratospheric cloud nucleation. Molecular-level knowledge about the interfacial distribution of these inorganic species and their perturbation of water organization facilitates a better understanding of the reactivity and growth of atmospheric aerosols and of the aerosol surface charge, thus shedding light on topics of air pollution, climate change, and thundercloud electrification. Here, the air/aqueous interface of NaHSO4, NH4HSO4, and Mg(HSO4)2 salt solutions as well as H2SO4 and HCl acid solutions are investigated by means of vibrational sum frequency generation (VSFG) and heterodyne-detected (HD) VSFG spectroscopy. VSFG spectra of all acid solutions show higher SFG response in the OH-bonded region relative to neat water, with 1.1 M H2SO4 being more enhanced than 1.1 M HCl. In addition, VSFG spectra of bisulfate salt solutions highly resemble that of the dilute H2SO4 solution (0.26 M) at a comparable pH. HD-VSFG (Im χ((2))) spectra of acid and bisulfate salt solutions further reveal that hydrogen-bonded water molecules are oriented preferentially toward the bulk liquid phase. General agreement between Im χ((2)) spectra of 1.1 M H2SO4 and 1.1 M HCl acid solutions indicate that HSO4(-) ions have a similar surface preference as that of chloride (Cl(-)) ions. By comparing the direction and magnitude of the electric fields arising from the interfacial ion distributions and the concentration of each species, the most reasonable relative surface preference that can be deduced from a simplified model follows the order H3O(+) > HSO4(-) > Na(+), NH4(+), Mg(2+) > SO4(2-). Interestingly

  5. Influence of microenvironment pH, humidity, and temperature on the stability of polymorphic and amorphous forms of clopidogrel bisulfate

    DEFF Research Database (Denmark)

    Raijada, Dhara K; Singh, Saranjit; Bansal, Arvind K;

    2010-01-01

    The effect of microenvironment pH, humidity, and temperature was evaluated on the stability of polymorphic and amorphous forms of clopidogrel bisulfate, when present alone or in combinations. Oxalic acid and sodium carbonate were used as solid stressors to create acidic and alkaline pH, respectiv......The effect of microenvironment pH, humidity, and temperature was evaluated on the stability of polymorphic and amorphous forms of clopidogrel bisulfate, when present alone or in combinations. Oxalic acid and sodium carbonate were used as solid stressors to create acidic and alkaline p...... more degradation than the individual forms above critical relative humidity (85% RH). Similar higher degradation was observed between 75% RH and 85% RH in case of acid-stressed samples. In alkaline microenvironment, all the samples showed identical decomposition attributed to conversion of bisulfate...

  6. Experimental and theoretical enthalpies of formation of glycine-based sulfate/bisulfate amino acid ionic liquids.

    Science.gov (United States)

    Zhu, Jing-Fang; He, Ling; Zhang, Lei; Huang, Ming; Tao, Guo-Hong

    2012-01-12

    The experimental and theoretical enthalpies of formation of several structural-similar glycine-based sulfate/bisulfate amino acid ionic liquids including glycine sulfate (Gly(2)SO(4), 1), glycine bisulfate (GlyHSO(4), 2), N,N-dimethylglycine sulfate ([DMGly](2)SO(4), 3), N,N-dimethylglycine bisulfate ([DMGly]HSO(4), 4), N,N-dimethylglycine methyl ester sulfate ([DMGlyC(1)](2)SO(4), 5), N,N-dimethylglycine methyl ester bisulfate ([DMGlyC(1)]HSO(4), 6), N,N,N-trimethylglycine methyl ester sulfate ([TMGlyC(1)](2)SO(4), 7), and N,N,N-trimethylglycine methyl ester bisulfate ([TMGlyC(1)]HSO(4), 8) were studied. Their experimental enthalpies of formation were obtained from the corresponding energies of combustion determined by the bomb calorimetry method. The enthalpies of formation of these amino acid ionic liquids are in the range from -1406 kJ mol(-1) to -1128 kJ mol(-1). Systematic theoretical study on these amino acid ionic liquids were performed by quantum chemistry calculation using the Gaussian03 suite of programs. The geometric optimization and the frequency analyses are carried out using the B3LYP method with the 6-31+G** basis set. Their calculated enthalpies of formation were derived from the single point energies carried out with the HF/6-31+G**, B3LYP/6-31+G**, B3LYP/6-311++G**, and MP2/6-311++G** level of theory, respectively. The relevance of experimental and calculated enthalpies of formation was studied. The calculated enthalpies of formation are in good agreement with their experimental data in less than 3% error. PMID:22148242

  7. Andrographolide Sodium Bisulfate Prevents UV-Induced Skin Photoaging through Inhibiting Oxidative Stress and Inflammation

    Directory of Open Access Journals (Sweden)

    Janis Ya-Xian Zhan

    2016-01-01

    Full Text Available Andrographolide sodium bisulfate (ASB, a water-soluble form made from andrographolide through sulfonating reaction, is an antioxidant and anti-inflammatory drug; however, the antiphotoaging effect of ASB has still not been revealed. Oxidative stress and inflammation are known to be responsible for ultraviolet (UV irradiation induced skin damage and consequently premature aging. In this study, we aimed at examining the effect of ASB on UV-induced skin photoaging of mice by physiological and histological analysis of skin and examination of skin antioxidant enzymes and immunity analyses. Results showed that topical administration of ASB suppressed the UV-induced skin thickness, elasticity, wrinkles, and water content, while ASB, especially at dose of 3.6 mg/mouse, increased the skin collagen content by about 53.17%, decreased the epidermal thickness by about 41.38%, and prevented the UV-induced disruption of collagen fibers and elastic fibers. Furthermore, ASB decreased MDA level by about 40.21% and upregulated the activities of SOD and CAT and downregulated the production of IL-1β, IL-6, IL-10, and TNF-α in UV-irradiated mice. Our study confirmed the protective effect of ASB against UV-induced photoaging and initially indicated that this effect can be attributed to its antioxidant and anti-inflammatory activities in vivo, suggesting that ASB may be a potential antiphotoaging agent.

  8. The Electrochemical Reduction of Hydrogen in the Presence of Bisulfate on Platinum(111)

    CERN Document Server

    Blum, L; Huckaby, Dale A.

    2001-01-01

    A new model for the intermediate compound of the hydrogen evolution reaction (HER) is proposed, for the electrochemical reduction of hydrogen in the presence of bisulfate on platinum(111). The formation of this compound, a regular 2 dimensional honeycomb ice lattice, occurs by a first order phase transitions that involves the reorientation of water molecules. The model is analyzed using new and simple effective cluster approach which highlights the relevant transitions in system. This method is based on the cluster variation method used successfully in our previous work on the UPD of Cu onto Au(111), and permits us to explore a large region of parameter space, an essential feature to study this complex system. The theory makes full use of the properties of the diffuse layer: The water molecule is reoriented as the potential is changed. For positive potentials it forms linear chains which are responsible for the $\\sqrt 3 \\times \\sqrt 7$ structure of the sulfate observed by STM. At negative potentials water tur...

  9. Andrographolide Sodium Bisulfate Prevents UV-Induced Skin Photoaging through Inhibiting Oxidative Stress and Inflammation.

    Science.gov (United States)

    Zhan, Janis Ya-Xian; Wang, Xiu-Fen; Liu, Yu-Hong; Zhang, Zhen-Biao; Wang, Lan; Chen, Jian-Nan; Huang, Song; Zeng, Hui-Fang; Lai, Xiao-Ping

    2016-01-01

    Andrographolide sodium bisulfate (ASB), a water-soluble form made from andrographolide through sulfonating reaction, is an antioxidant and anti-inflammatory drug; however, the antiphotoaging effect of ASB has still not been revealed. Oxidative stress and inflammation are known to be responsible for ultraviolet (UV) irradiation induced skin damage and consequently premature aging. In this study, we aimed at examining the effect of ASB on UV-induced skin photoaging of mice by physiological and histological analysis of skin and examination of skin antioxidant enzymes and immunity analyses. Results showed that topical administration of ASB suppressed the UV-induced skin thickness, elasticity, wrinkles, and water content, while ASB, especially at dose of 3.6 mg/mouse, increased the skin collagen content by about 53.17%, decreased the epidermal thickness by about 41.38%, and prevented the UV-induced disruption of collagen fibers and elastic fibers. Furthermore, ASB decreased MDA level by about 40.21% and upregulated the activities of SOD and CAT and downregulated the production of IL-1β, IL-6, IL-10, and TNF-α in UV-irradiated mice. Our study confirmed the protective effect of ASB against UV-induced photoaging and initially indicated that this effect can be attributed to its antioxidant and anti-inflammatory activities in vivo, suggesting that ASB may be a potential antiphotoaging agent. PMID:26903706

  10. Toxicity of Ambient Particulate Matter (PM10) I. Acute toxicity study in asthmatic mice following 3-day exposure to ultrafine and fine ammonium bisulfate, a model compound for secondary aerosol fraction of PM10

    NARCIS (Netherlands)

    Cassee FR; Dormans JAMA; Loveren H van; Bree L van; Rombout PJA; LEO; LPI

    1998-01-01

    Presented here is the first in a series of 3-day inhalation studies aimed to generate data on the health effects of inhaled ultrafine and fine ammonium bisulfate aerosols as model compound for the secondary fraction of particulate matter (PM10). Epidemiologic studies identified asthmatics as a risk

  11. Toxicity of Ambient Particulate Matter IV: Acute toxicity study in pulmonary hypertensive rats after exposure to model compounds for the secondary aerosol fraction of PM10 - ammonium bisulfate, ferrosulfate and nitrate

    NARCIS (Netherlands)

    Cassee FR; Boere AJF; Fokkens PHB; Dormans JAMA; Bree L van; Rombout PJA; LEO; LPI

    1999-01-01

    This (4th) report on the toxicity of ambient particulate matter (PM) presents effects of the model compounds for PM in ambient air - ammonium bisulfate, ammonium ferrosulfate and ammonium nitrate - on healthy rats and rats with monocrotaline-induced pulmonary hypertension (PH). The objective was bas

  12. Synthesis of n-Butyl Salicylate Catalyzed by Sodium Bisulfate%硫酸氢钠催化合成水杨酸正丁酯

    Institute of Scientific and Technical Information of China (English)

    吴春燕

    2015-01-01

    Butyl salicylate was synthesized from salicylic acid and n-butanol catalyzed by sodium bisulfate.The effect of the molar ratio of n-butanol to salicylic acid,the reaction time,the amount of catalyst was discussed. Optimal conditions were obtained:the molar ratio of n-butanol to salicylic acid was 1.6:1, the reaction time was 4h and the mass ratio of catalyst to salicylic acid was 6%, the yield of butyl salicylate was 60.66%.%以水杨酸和正丁醇为原料,硫酸氢钠为催化剂,合成了水杨酸正丁酯。考察了正丁醇与水杨酸摩尔比、反应时间、催化剂用量对酯化收率的影响。通过实验得到最佳工艺条件为:正丁醇与水杨酸摩尔比为1.6∶1,反应时间为4h,催化剂用量为水杨酸用量的6%(质量分数),水杨酸正丁酯收率可达60.66%。

  13. 硫酸氢钠催化合成水杨酸正丁酯%Synthesis of n-Butyl Salicylate Catalyzed by Sodium Bisulfate

    Institute of Scientific and Technical Information of China (English)

    吴春燕

    2015-01-01

    以水杨酸和正丁醇为原料,硫酸氢钠为催化剂,合成了水杨酸正丁酯。考察了正丁醇与水杨酸摩尔比、反应时间、催化剂用量对酯化收率的影响。通过实验得到最佳工艺条件为:正丁醇与水杨酸摩尔比为1.6∶1,反应时间为4h,催化剂用量为水杨酸用量的6%(质量分数),水杨酸正丁酯收率可达60.66%。%Butyl salicylate was synthesized from salicylic acid and n-butanol catalyzed by sodium bisulfate.The effect of the molar ratio of n-butanol to salicylic acid,the reaction time,the amount of catalyst was discussed. Optimal conditions were obtained:the molar ratio of n-butanol to salicylic acid was 1.6:1, the reaction time was 4h and the mass ratio of catalyst to salicylic acid was 6%, the yield of butyl salicylate was 60.66%.

  14. 硫酸氢氯吡格雷片处方和制备工艺研究%Investigation of Formulation and in-Process Parameters of Clopidogrel Bisulfate Tablets

    Institute of Scientific and Technical Information of China (English)

    高原; 蔡轶军; 高峰

    2011-01-01

    目的 制备稳定的硫酸氢氯吡格雷片(CPG,Ⅰ型),并考察影响颗粒特性的关键处方和工艺参数,以解决压片时的黏片现象,并确保稳定性.方法 研究原料辅料的相容性并筛选处方,考察直接压片、滚压法和熔融法对杂质、压片特性和溶出度的影响.结果 影响CPG稳定性最显著的因素是水分,其次为光照和温度;与滚压法、直接压片相比,熔融制粒的工艺更优;硬脂富马酸钠可防止压片时的黏片现象;溶出度与进口"波立维"相似因子f2>50;3个月加速实验结果表明,稳定性良好.结论 制备工艺重现性良好,片剂质量稳定.%OBJECTIVE To investigate the formulation and process for preparing stable clopidogrel bisulfate tablets (Form Ⅰ) by elucidating the critical formulation and in-process parameters affecting critical granule properties, in order to solve sticking problems in tablet processing as well as improving stability under storage. METHODS Drug-excipient interactions were evaluated, and different dry granulations such as direct compression, melt granulation and roller compaction were compared, in terms of impurity levels, tablet properties and in vitro dissolution. RESULTS The stability of free clopidogrel bisulfate was liable to the high moisture, strong light and elevated temperature. Compared with direct compression and roller compaction, melt granulation was more suitable to prepare clopidogrel bisulfate tablet. Sodium stearyl fumarate avoided sticking problem in tablet processing with PEG 6000. Comparable dissolution profiles were obtained and similar to that of Pavix of Sinofi, with the similar factors above 50. Furthermore, the accelerated stability test suggested that tablets prepared by melt granulation under storage at 40 C and 75% RH for 3 months were stable and showed good physicochemical properties. CONCLUSION The CPG tablets were stable and the established processes were simple and reproducible.

  15. 二氧化硅负载硫酸氢钠催化合成乙酰水杨酸%Synthesis of acetyl salicylic acid with silica supported sodium bisulfate as catalyst

    Institute of Scientific and Technical Information of China (English)

    陈盛余; 蓝姣玉; 赵丹丹; 李丽; 韦唯; 肖彩玲; 张才莲

    2015-01-01

    The synthesis of acetyl salicylic acid with salicylic acid and acetic anhydride as reactants and sodium bisulfate as catalys supported by silica was studied.The factors influencing its catalytic performance were investigated and optimized , including reaction time, reaction temperature, the amount of catalyst.When the amount of salicylic acid was 7.0 g and the amount of acetic anhydride was 11.0 g,the optimum reaction conditions were as follows: the amount of catalyst was 0.6 g;the reaction time was 50 min , the reaction temperature was 80℃.The yield of acetyl salicylic acid was 80.1%.The catalyst could be recycled and used for 3 times.The process would improve the production of acetyl salicylic acid.%研究了以二氧化硅负载硫酸氢钠为催化剂,水杨酸和乙酸酐为原料合成乙酰水杨酸的工艺。考察了催化剂用量、反应时间、反应温度的影响。当固定水杨酸为7.0 g,乙酸酐为11.0 g时,乙酰水杨酸的优化合成条件为:催化剂用量0.6 g,反应时间为50 min,反应温度为80℃。在此条件下,乙酰水杨酸产率为80.1%。催化剂能够重复使用3次。该工艺将改善乙酰水杨酸的生产。

  16. Factorial study on influence of gas generating agent and diluent on drug release kinetics of clopidogrel bisulfate floating tablets

    OpenAIRE

    K R Koteswara Rao; K Rajya Lakshmi; T. E. G. K. Murthy; A Sivarama Prasad

    2013-01-01

    The purpose of present work was to formulate and characterize a floating drug delivery system for Clopidogrel bisulphate to improve bioavailability and to minimize the side-effects of the drug such as gastric bleeding and drug resistance development. Clopidogrel floating tablets were prepared by direct compression technique by the use of xanthan gum at different concentrations (20%, 25% and 30% w/w). Sodium bicarbonate (15% w/w) and microcrystalline cellulose (MCC) (30% w/w) were used as gas ...

  17. Factorial study on influence of gas generating agent and diluent on drug release kinetics of clopidogrel bisulfate floating tablets

    Directory of Open Access Journals (Sweden)

    K R Koteswara Rao

    2013-01-01

    Full Text Available The purpose of present work was to formulate and characterize a floating drug delivery system for Clopidogrel bisulphate to improve bioavailability and to minimize the side-effects of the drug such as gastric bleeding and drug resistance development. Clopidogrel floating tablets were prepared by direct compression technique by the use of xanthan gum at different concentrations (20%, 25% and 30% w/w. Sodium bicarbonate (15% w/w and microcrystalline cellulose (MCC (30% w/w were used as gas generating agent and diluent respectively. The effects of sodium bicarbonate and MCC on the drug release kinetics and floating properties were investigated. A 2 2 factorial design was applied systematically to optimized formulation. The percentage amount of sodium bicarbonate (X 1 and percentage amount of MCC (X 2 were selected as independent variables. The drug release rate constant (K and time required for 85% drug dissolution (T85 was selected as dependent variables. Factorial design revealed that the percentage amount of sodium bicarbonate and MCC had insignificant effect on drug release kinetics (K, T85 within the chosen levels and a high level of sodium bicarbonate (X 1 and the low level of MCC (X 2 favor the preparation of clopidogrel floating tablets. All the Clopidogrel floating formulations followed first order kinetics, Higuchi drug release kinetics with diffusion as the dominant mechanism of drug release. As per Korsmeyer-Peppas equation, the release exponent "n" ranged 0.455-0.654 indicating that drug release from all the formulations was by non-fickian diffusion mechanism.

  18. Development and Validation of an HPLC Method for Simultaneous Quantification of Clopidogrel Bisulfate, Its Carboxylic Acid Metabolite, and Atorvastatin in Human Plasma: Application to a Pharmacokinetic Study

    Directory of Open Access Journals (Sweden)

    Octavian Croitoru

    2015-01-01

    Full Text Available A simple, sensitive, and specific reversed phase liquid chromatographic method was developed and validated for simultaneous quantification of clopidogrel, its carboxylic acid metabolite, and atorvastatin in human serum. Plasma samples were deproteinized with acetonitrile and ibuprofen was chosen as internal standard. Chromatographic separation was performed on an BDS Hypersil C18 column (250 × 4.6 mm; 5 μm via gradient elution with mobile phase consisting of 10 mM phosphoric acid (sodium buffer solution (pH = 2.6 adjusted with 85% orthophosphoric acid : acetonitrile : methanol with flow rate of 1 mL·min−1. Detection was achieved with PDA detector at 220 nm. The method was validated in terms of linearity, sensitivity, precision, accuracy, limit of quantification, and stability tests. Calibration curves of the analytes were found to be linear in the range of 0.008–2 μg·mL−1 for clopidogrel, 0.01–4 μg·mL−1 for its carboxylic acid metabolite, and 0.005–2.5 μg·mL−1 for atorvastatin. The results of accuracy (as recovery with ibuprofen as internal standard were in the range of 96–98% for clopidogrel, 94–98% for its carboxylic acid metabolite, and 90–99% for atorvastatin, respectively.

  19. 硫酸氢钾催化合成尼泊金丁酯%Synthesis of Butyl Paraben Catalyzed by Potassium Bisulfate

    Institute of Scientific and Technical Information of China (English)

    陈丹云; 周慧; 何建英

    2006-01-01

    采用KHSO4为催化剂合成了尼泊金丁酯,考察了催化剂用量、正丁醇与对羟基苯甲酸摩尔比、反应时间、催化剂重复使用次数及带水剂等因素对收率的影响.结果表明:KHSO4具有催化活性高,易分离回收,重复使用性良好等优势.最佳反应条件为:正丁醇与对羟基苯甲酸摩尔比为3∶1,催化剂用量3 g,反应时间3h,收率92.9%.

  20. Bisulfate – cluster based atmospheric pressure chemical ionization mass spectrometer for high-sensitivity (< 100 ppqV) detection of atmospheric dimethyl amine: proof-of-concept and first ambient data from boreal forest

    OpenAIRE

    Sipilä, M.; N. Sarnela; Jokinen, T; Junninen, H.; Hakala, J.; Rissanen, M. P.; Praplan, A.; M. Simon; A. Kürten; BIANCHI, F.; Dommen, J; J. Curtius; T. Petäjä; Worsnop, D.R.

    2015-01-01

    Atmospheric amines may play a crucial role in formation of new aerosol particles via nucleation with sulfuric acid. Recent studies have revealed that concentrations below 1 pptV can significantly promote nucleation of sulfuric acid particles. While sulfuric acid detection is relatively straightforward, no amine measurements to date have been able to reach the critical sub-pptV concentration range and atmospheric amine concentrations are in general poorly characterized. In th...

  1. Proton conducting membranes for high temperature fuel cells with solid state water free membranes

    Science.gov (United States)

    Narayanan, Sekharipuram R. (Inventor); Yen, Shiao-Pin S. (Inventor)

    2006-01-01

    A water free, proton conducting membrane for use in a fuel cell is fabricated as a highly conducting sheet of converted solid state organic amine salt, such as converted acid salt of triethylenediamine with two quaternized tertiary nitrogen atoms, combined with a nanoparticulate oxide and a stable binder combined with the converted solid state organic amine salt to form a polymeric electrolyte membrane. In one embodiment the membrane is derived from triethylenediamine sulfate, hydrogen phosphate or trifiate, an oxoanion with at least one ionizable hydrogen, organic tertiary amine bisulfate, polymeric quaternized amine bisulfate or phosphate, or polymeric organic compounds with quaternizable nitrogen combined with Nafion to form an intimate network with ionic interactions.

  2. Acidification of calf bedding reduces fly development and bacterial abundance

    Science.gov (United States)

    Environmental stressors, such as high fly density, can impact calf well-being. Sodium bisulfate (SBS) is an acidifier that reduces the pH of flooring and bedding, creating a medium that neither bacteria nor immature flies (also known as larvae or maggots) can thrive in. Two experiments were conducte...

  3. Effect of on-farm litter acidification treatments on Campylobacter and Salmonella populations in comercial broiler houses in northeast Georgia.

    Science.gov (United States)

    Two commercially available litter treatments, aluminum sulfate and sodium bisulfate, were tested to determine their effect on Campylobacter and Salmonella levels associated with commercial broilers during a 6 week grow-out period. A total of 20 broiler houses at 10 different locations were studied;...

  4. TECHNOLOGY OF PLANT FEED ADDITIVES FOR POULTRY

    OpenAIRE

    Koshchaeva O. V.; Kalyuzhniy S. A.; Khathakumov S. S.; Likhoman A. V.

    2014-01-01

    The work on the development of technology for production of feed additives from soybean seeds and fruits of pumpkin has shown that the use of sodium bisulfate and lactic acid bacteria provide a high content of carotene in pumpkin paste (948 mg / kg and 819 mg / kg, respectively), and grinding soy before drying protein and vitamin supplements raises safety of carotene without destroying the urease

  5. MBRidge: an accurate and cost-effective method for profiling DNA methylome at single-base resolution

    OpenAIRE

    Cai, Wanshi; Mao, Fengbiao; Teng, Huajing; Cai, Tao; Zhao, Fangqing; Wu, Jinyu; Sun, Zhong Sheng

    2015-01-01

    Organisms and cells, in response to environmental influences or during development, undergo considerable changes in DNA methylation on a genome-wide scale, which are linked to a variety of biological processes. Using MethylC-seq to decipher DNA methylome at single-base resolution is prohibitively costly. In this study, we develop a novel approach, named MBRidge, to detect the methylation levels of repertoire CpGs, by innovatively introducing C-hydroxylmethylated adapters and bisulfate treatme...

  6. Interleukin-8 enhances nonoxidative intracellular killing of Mycobacterium fortuitum by human granulocytes.

    OpenAIRE

    Nibbering, P. H.; Pos, O; Stevenhagen, A; van Furth, R

    1993-01-01

    The results of this study show that recombinant interleukin-8 (IL-8) enhances the intracellular killing of Mycobacterium fortuitum by human granulocytes. This chemokine did not stimulate the phagocytosis of M. fortuitum by granulocytes at various bacterium-to-cell ratios. The killing process was not affected by the NADPH oxidase inhibitor diphenyleneiodonium bisulfate, which indicates that recombinant IL-8 stimulates oxygen-independent mycobactericidal mechanisms of granulocytes. IL-8 did not...

  7. Chemical reduction and sulfur-isotope effects of sulfate by organic matter under hydrothermal conditions

    International Nuclear Information System (INIS)

    Under hydrothermal conditions sulfuric acid, sodium bisulfate and sodium sulfate solutions were reduced by dextrose to hydrogen sulfide in order to clarify the origin of sulfide species in hot-springs, geothermal water and ore-forming fluids. At temperatures above 2500C, reduction of sulfuric acid and at above 3000C of sodium bisulfate and sodium sulfate was observed. The reduction rate depends fairly well on the temperatures, pH and sulfate species. The reduction of sulfate seems to be a first-order reaction. Sulfur-isotope compositions of sulfate and hydrogen sulfide were measured in order to disclose isotope effects in the reduction of sulfate. The reduction of sulfuric acid and sodium bisulfate solution results in enrichment of 32S in the hydrogen sulfide and of the heavy isotope into residual sulfate. The fractionation factor in the reduction is independent of the temperature and is seen to be 1.007 to 1.009, in agreement with previously published values. (Auth.)

  8. Spectrophotometric determination of trace quantities of iodide after separation from large quantities of bromide, chloride, or sulfate by solvent extraction

    International Nuclear Information System (INIS)

    Iodide solutions were reacted with 2,4,6-triphenylpyrylium bisulfate to yield the triphenylpyrylium iodide which was extracted with chloroform and spectrophotometrically determined. The interference from perchlorate, bromide, chloride, and sulfate ions on the iodide determination was evaluated. An analytical procedure for the determination of iodide present as the iodate was developed using sodium sulfite to reduce the iodate to iodide. The use of this method for the determination of KI in commercial iodized salt gave results comparable to those obtained by the AOAC iodometric method. (U.S.)

  9. Product Protection, the Key to Developing High Performance Methane Selective Oxidation Catalysts

    OpenAIRE

    Ahlquist, Mårten; Nielsen, Robert J.; Periana, Roy A.; Goddard, William A.

    2009-01-01

    Selective, direct conversion of methane to methanol might seem an impossible task since the C−H bond energy of methane is 105 kcal mol^(−1) compared to the C−H bond energy for methanol of 94. We show here that the Catalytica catalyst is successful because the methanol is protected as methyl bisulfate, which is substantially less reactive than methanol toward the catalyst. This analysis suggests a limiting performance for systems that operate by this type of protection that is well above the C...

  10. Amine reactivity with charged sulfuric acid clusters

    Directory of Open Access Journals (Sweden)

    B. R. Bzdek

    2011-08-01

    Full Text Available The distribution of charged species produced by electrospray of an ammonium sulfate solution in both positive and negative polarities is examined using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS. Positively-charged ammonium bisulfate cluster composition differs significantly from negatively-charged cluster composition. For positively-charged clusters all sulfuric acid is neutralized to bisulfate, whereas for negatively-charged clusters the degree of sulfuric acid neutralization is cluster size-dependent. With increasing cluster size (and, therefore, a decreasing role of charge, both positively- and negatively-charged cluster compositions converge toward ammonium bisulfate. The reactivity of negatively-charged sulfuric acid-ammonia clusters with dimethylamine and ammonia is also investigated by FTICR-MS. Two series of negatively-charged clusters are investigated: [(HSO4(H2SO4x] and [(NH4x(HSO4x+1(H2SO43]. Dimethylamine substitution for ammonia in [(NH4 x(HSO4 x+1(H2SO43] clusters is nearly collision-limited, and subsequent addition of dimethylamine to neutralize H2SO4 to bisulfate is within one order of magnitude of the substitution rate. Dimethylamine addition to [(HSO4 (H2SO4 x] clusters is either not observed or very slow. The results of this study indicate that amine chemistry will be evident and important only in large ambient negative ions (>m/z 400, whereas amine chemistry may be evident in small ambient positive ions. Addition of ammonia to unneutralized clusters occurs at a rate that is ~2–3 orders of magnitude slower than incorporation of dimethylamine either by substitution or addition

  11. Liquid-liquid extraction of chromium (VI) from sulfuric acid solutions using tri-n-dodecylamine/kerosene

    International Nuclear Information System (INIS)

    Extraction of chromium (VI) from sulfuric acid solutions with tri-n-dodecylamine containing octanol-1 as a modifier in kerosene was investigated. All parameters influencing the extraction of chromium (VI) (time of agitation, concentrations of chromium (VI), sulfuric acid, tri-n-dodecylamine and temperature) were studied. Forst of all, tri-n-dodecylamine reacts with sulfuric acid to form tri-n-dodecylamine sulfate and bisulfate salts, then, dichromate ions is extracted by amine bisulfate. The mathematical treatment of the obtained date enabled us to calculate the formation of equilibrium constant of (TDAH)2SO4 TDAHHSO4 and (TDAH)2 Cγ2O7 at 25 Centigrade and have been found to be K1=109.642(14/mol4), K2= 10-0.899(L/mol) and Kex 1010.55 respectively. Stripping of more than 99% of chromium (VI) from the organic phase of tri-n-dodecylamine/kerosene can be easily achieved in two stages using 0.05 M sodium carbonate solution. The synergistic effect of tri-n-butylphosphate and tri-n-octylphosphine oxide on the extraction of chromium (VI) were also studied. (author)

  12. Comparison of normal and asthmatic subjects' responses to sulfate pollutant aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Utell, M.J.; Morrow, P.E.; Hyde, R.W.

    1980-01-01

    Epidemiological studies support an association between elevated levels of sulfates and acute respiratory disease. To determine if these pollutants produce airway hyperreactivity, 16 normal and 17 asthmatic subjects inhaled a control NaCl aerosol and the following sulfates: ammonium sulfate, sodium bisulfate, ammonium bisulfate, and sulfuric acid. A Lovelace generator produced particles with an average MMAD of approx. 1.0 ..mu..m (sigma/sub g/ approx. = 2.0) and concentrations of 0.1 and 1.0 mg/m/sup 3/. By double-blind randomization, all subjects breathed these aerosols for a 16-minute period. To determine if sulfate inhalation caused increased reactivity to a known bronchoconstrictor, all subjects inhaled carbachol following each 16-minute exposure. Before, during, and after exposure, pulmonary function studies were performed. When compared to NaCl, sulfate (1 mg/m/sup 3/) produced significant reductions in airway conductance and flow rates in asthmatics. The two most sensitive asthmatics demonstrated changes even at 0.1 mg/m/sup 3/ sulfate. To a far more significant degree, the bronchoconstrictor action of carbachol was potentiated by sulfates more or less in relation to their acidity in normals and asthmatics.

  13. Elemental composition and clustering behaviour of α-pinene oxidation products for different oxidation conditions

    Directory of Open Access Journals (Sweden)

    A. P. Praplan

    2015-04-01

    Full Text Available This study presents the difference between oxidised organic compounds formed by α-pinene oxidation under various conditions in the CLOUD environmental chamber: (1 pure ozonolysis (in the presence of hydrogen as hydroxyl radical (OH scavenger and (2 OH oxidation (initiated by nitrous acid (HONO photolysis by ultraviolet light in the absence of ozone. We discuss results from three Atmospheric Pressure interface Time-of-Flight (APi-TOF mass spectrometers measuring simultaneously the composition of naturally charged as well as neutral species (via chemical ionisation with nitrate. Natural chemical ionisation takes place in the CLOUD chamber and organic oxidised compounds form clusters with nitrate, bisulfate, bisulfate/sulfuric acid clusters, ammonium, and dimethylaminium, or get protonated. The results from this study show that this process is selective for various oxidised organic compounds with low molar mass and ions, so that in order to obtain a comprehensive picture of the elemental composition of oxidation products and their clustering behaviour, several instruments must be used. We compare oxidation products containing 10 and 20 carbon atoms and show that highly oxidised organic compounds are formed in the early stages of the oxidation.

  14. 由复合催化剂催化合成硬脂酸乙酯%Catalytic Synthesis of Ethyl Stearate by Using Composite Catalyst

    Institute of Scientific and Technical Information of China (English)

    吴晖; 陈红; 李勤涛; 熊双喜

    2013-01-01

    The sodium bisulfate and concentrated sulfuric acid can be used as a catalyst for esterification.Using stearic acid and ethanol as raw material,sodium bisulfate and sulfuric acid catalyst for the synthesis of stearic acid ester compound were studied.The optimum reaction conditions are as follows:acid molar ratio n (stearic acid)∶n (ethanol) was 1∶8,the amount of catalyst 1.4 g,Complex catalyst in concentrated sulfuric acid and sodium hydrogen sulfate ratio of 1.8∶1,and the reaction time was one hundred and twenty minutes.Esterification rate can be up to 82%.%硫酸氢钠和浓硫酸能够作为酯化反应的催化剂,本文研究了以硬脂酸和无水乙醇为原料,硫酸氢钠和浓硫酸为复合催化剂合成硬脂酸乙酯.最佳反应条件为:醇酸摩尔比n(硬脂酸)∶n(无水乙醇)为1∶8,催化剂用量为1.4g,复合催化剂中硫酸氢钠与浓硫酸之比为1.8∶1,反应时间120 min,酯化率最高可达82%.

  15. Investigation of spontaneous passivation of stainless steels modified with ruthenium

    Energy Technology Data Exchange (ETDEWEB)

    Baradlai, P. [Veszprem Univ. (Hungary). Dept. of Radiochem.; Potgieter, J.H. [PPC Technical Service, Johannesburg (South Africa); Barnard, W.O. [Dept. of Physics, Univ. of Pretoria (South Africa); Tomcsanyi, L. [Dept. of Physical Chemistry, Univ. of Veszprem (Hungary); Varga, K. [Veszprem Univ. (Hungary). Dept. of Radiochem.

    1995-11-01

    In this paper, time, potential and concentration dependence of HSO{sub 4}{sup -}/SO{sub 4}{sup 2-} and Cl{sup -} accumulations measured by an in-situ radiotracer method on surface oxide layers of stainless steels of various microstructures (austenitic or duplex) and compositions (in the presence and absence of Ru as additive) are presented and discussed. Several independent techniques such as AES, XPS and ICP Optical Emission Spectrometry are also used to characterise the complex features of the passivation phenomena of steels modified with ruthenium. The experimental results reveal that the surface excess values of bisulfate/sulfate ions are much higher (up to {Gamma}=1.5x10{sup -9} mol cm{sup -2}) as well as their interaction with passive oxide layer is substantially stronger than those of chloride ions on all stainless steels studied. Both the extent and the strong character of bisulfate/sulfate accumulation are most likely related to the redistribution of the main alloying components (Cr, Ni, Mo) as well as the Ru in the surface oxide films formed on steels passivated spontaneously in dilute HCl and H{sub 2}SO{sub 4}. (orig.)

  16. Size-resolved morphological properties of the high Arctic summer aerosol during ASCOS-2008

    Science.gov (United States)

    Hamacher-Barth, Evelyne; Leck, Caroline; Jansson, Kjell

    2016-05-01

    The representation of aerosol properties and processes in climate models is fraught with large uncertainties. Especially at high northern latitudes a strong underprediction of aerosol concentrations and nucleation events is observed and can only be constrained by in situ observations based on the analysis of individual aerosol particles. To further reduce the uncertainties surrounding aerosol properties and their potential role as cloud condensation nuclei this study provides observational data resolved over size on morphological and chemical properties of aerosol particles collected in the summer high Arctic, north of 80° N. Aerosol particles were imaged with scanning and transmission electron microscopy and further evaluated with digital image analysis. In total, 3909 aerosol particles were imaged and categorized according to morphological similarities into three gross morphological groups: single particles, gel particles, and halo particles. Single particles were observed between 15 and 800 nm in diameter and represent the dominating type of particles (82 %). The majority of particles appeared to be marine gels with a broad Aitken mode peaking at 70 nm and accompanied by a minor fraction of ammonium (bi)sulfate with a maximum at 170 nm in number concentration. Gel particles (11 % of all particles) were observed between 45 and 800 nm with a maximum at 154 nm in diameter. Imaging with transmission electron microscopy allowed further morphological discrimination of gel particles in "aggregate" particles, "aggregate with film" particles, and "mucus-like" particles. Halo particles were observed above 75 nm and appeared to be ammonium (bi)sulfate (59 % of halo particles), gel matter (19 %), or decomposed gel matter (22 %), which were internally mixed with sulfuric acid, methane sulfonic acid, or ammonium (bi)sulfate with a maximum at 161 nm in diameter. Elemental dispersive X-ray spectroscopy analysis of individual particles revealed a prevalence of the monovalent

  17. Wastes and by-products - alternatives for agricultural use

    International Nuclear Information System (INIS)

    Top address a growing national problem with generation of wastes and by-products, TVA has been involved for several years with developing and commercializing environmentally responsible practices for eliminating, minimizing, or utilizing various wastes/by-products. In many cases, reducing waste generation is impractical, but the wastes/by-products can be converted into other environmentally sound products. In some instances, conversion of safe, value-added agricultural products in the best or only practical alternative. TVA is currently involved with a diversity of projects converting wastes/by-products into safe, economical, and agriculturally beneficial products. Environmental improvement projects have involved poultry litter, cellulosic wastes, used battery acid, ammonium sulfate fines, lead smelting effluents, deep-welled sulfuric acid/ammonium bisulfate solutions, wood ash, waste magnesium ammonium sulfate slurry from recording tape production, and ammunition plant waste sodium nitrate/ammonium nitrate streams

  18. 固体酸催化合成水杨酸甲酯进展%Progress of Catalytic Synthesis for Methyl Salicylate with Solid Acid

    Institute of Scientific and Technical Information of China (English)

    刘美艳; 俞善信

    2011-01-01

    Solid acid is a good catalyst that can be used as catalyst for the esterification instead of sulphuric acid. The synthesis of methyl salicylate catalyzed by p-toluene sulfonic acid, amino sulfonic acid,strongly acidic cationic exchanged resin,cupric bromide, sodium bisulfate monohydrate, solid super acid,heteropoly acid and molecular sieve etc. were reviewed.%固体酸是一种优良的催化剂,能够替代硫酸作为酯化催化剂.评述了对甲苯磺酸、氨基磺酸、强酸性阳离子交换树脂、溴化铜、一水硫酸氢钠、固体超强酸、杂多酸和分子筛等催化合成水杨酸甲酯的方法.

  19. Methanol oxidation at platinum electrodes in acid solution: comparison between model and real catalysts

    Directory of Open Access Journals (Sweden)

    A. V. TRIPKOVIC

    2006-12-01

    Full Text Available Methanol oxidation in acid solution was studied at platinum single crystals, Pt(hkl, as the model catalyst, and at nanostructural platinum supported on high surface area carbon, Pt/C, as the real catalyst. The linear extrapolation method was used to determine the beginning of hydroxyl anion adsorption. Structural sensitivity of the adsorption was proved and a correlation with the onset of the methanol oxidation current was established at all catalysts. Bisulfate and chloride anions were found to decrease the methanol oxidation rate, but probably did not influence the reaction parth. The specific activity for the reaction increased in the sequence Pt(110 < Pt/C < Pt(111, suggesting that the activity of the supported Pt catalyst can be correlated with the activities of the dominating crystal planes on its surface.

  20. Solar concentration/destruction of pesticide rinsewater

    Energy Technology Data Exchange (ETDEWEB)

    Salladay, D.G.; Ash, D.H.; Sullivan, J.M.; Grinstead, J.H. Jr.; Hemmen, J.E.

    1992-09-01

    To address a growing national problem with generation of wastes and by-products, TVA has been involved for several years with developing and commercializing environmentally responsible practices for eliminating, minimizing, or utilizing various wastes/by-products. In many cases, reducing waste generation is impractical, but the wastes/by-products can be converted into other environmentally sound products. In some instances, conversion to safe, value-added agricultural products is the best or only practical alternative. TVA is currently involved with a diversity of projects converting wastes/by-products into safe, economical, and agriculturally beneficial products. Environmental improvement projects have involved poultry litter, cellulosic wastes, used battery acid, ammonium sulfate fines, lead smelting effluents, deep-welled sulfuric acid/ammonium bisulfate solutions, wood ash, waste magnesium ammonium sulfate slurry from recording tape production, and ammunition plant waste sodium nitrate/ammonium nitrate streams.

  1. Micro-Bubble Experiments at the Van de Graaff Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Z. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Wardle, Kent E. [Argonne National Lab. (ANL), Argonne, IL (United States); Quigley, K. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States); Youker, A. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, Vakhtang [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, James [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, D. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Chemerisov, S. D. [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, G. F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-02-01

    In order to test and verify the experimental designs at the linear accelerator (LINAC), several micro-scale bubble ("micro-bubble") experiments were conducted with the 3-MeV Van de Graaff (VDG) electron accelerator. The experimental setups included a square quartz tube, sodium bisulfate solution with different concentrations, cooling coils, gas chromatography (GC) system, raster magnets, and two high-resolution cameras that were controlled by a LabVIEW program. Different beam currents were applied in the VDG irradiation. Bubble generation (radiolysis), thermal expansion, thermal convection, and radiation damage were observed in the experiments. Photographs, videos, and gas formation (O2 + H2) data were collected. The micro-bubble experiments at VDG indicate that the design of the full-scale bubble experiments at the LINAC is reasonable.

  2. DNA methylation dynamics in the rat EGF gene promoter after partial hepatectomy

    Directory of Open Access Journals (Sweden)

    Deming Li

    2014-06-01

    Full Text Available Epidermal growth factor (EGF, a multifunctional growth factor, is a regulator in a wide variety of physiological processes. EGF plays an important role in the regulation of liver regeneration. This study was aimed at investigating the methylation level of EGF gene throughout liver regeneration. DNA of liver tissue from control rats and partial hepatectomy (PH rats at 10 time points was extracted and a 354 bp fragment including 10 CpG sites from the transcription start was amplified after DNA was modified by sodium bisulfate. The result of sequencing suggested that methylation ratio of four CpG sites was found to be significantly changed when PH group was compared to control group, in particular two of them were extremely striking. mRNA expression of EGF was down-regulated in total during liver regeneration. We think that the rat EGF promoter region is regulated by variation in DNA methylation during liver regeneration.

  3. Research on various factors influencing the moisture absorption property of sodium polyacrylate

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Sodium polyacrylate was synthesized with acrylic acid as the monomer, and sodium bisulfate and ammonium persulfate as the initiator, by means of aqueous solution polymerization. The factors influencing the properties of moisture absorption, such as monomer concentration, dosage of initiator, and reaction temperature were systematically investigated. The experimental results indicate that the moisture-absorbing property of this polymer was better than other traditional material, such as silica gel, and molecular sieve. The best reaction condition and formula are based on the orthogonal experiment design. The optimum moisture absorbency of sodium polyacrylate reaches 1.01 g/g. The mathematical correlation of this polymer with various factors and moisture absorbency is obtained based on the multiple regression analysis. The moisture content intuitive analysis table shows that neutralization degree has the most significant influence on moisture absorbency, followed by monomer concentration and reaction temperature, while other factors have less influence.

  4. Laboratory and field studies of stratospheric aerosols: Phase changes under high supersaturation

    Science.gov (United States)

    Hallet, John

    1991-01-01

    It is well known that water in the form of isolated small droplets supercool as much as 40 C below their equilibrium melting point. Solutions similarly supercool (with respect to water) and supersaturate (with respect of the solute). Experiments are described in which bulk solutions typical of atmospheric aerosols (nitric acid, sulfuric acid, and hydrates; ammonium sulfate; ammonium bisulfate; sodium chloride) are supercooled and/or supersaturated and nucleated to initiate crystal growth. Supersaturation of 300 percent is readily attainable, with linear growth of crystals increasing roughly as (supercooling/supersaturation)sup 2. The implication of the experiments is that the situation of metastability in polar stratosphere clouds is very likely, with nucleation only occuring under a high degree of supercooling or supersaturation.

  5. Wastes and by-products - alternatives for agricultural use

    Energy Technology Data Exchange (ETDEWEB)

    Boles, J.L.; Craft, D.J.; Parker, B.R.

    1994-10-01

    Top address a growing national problem with generation of wastes and by-products, TVA has been involved for several years with developing and commercializing environmentally responsible practices for eliminating, minimizing, or utilizing various wastes/by-products. In many cases, reducing waste generation is impractical, but the wastes/by-products can be converted into other environmentally sound products. In some instances, conversion of safe, value-added agricultural products in the best or only practical alternative. TVA is currently involved with a diversity of projects converting wastes/by-products into safe, economical, and agriculturally beneficial products. Environmental improvement projects have involved poultry litter, cellulosic wastes, used battery acid, ammonium sulfate fines, lead smelting effluents, deep-welled sulfuric acid/ammonium bisulfate solutions, wood ash, waste magnesium ammonium sulfate slurry from recording tape production, and ammunition plant waste sodium nitrate/ammonium nitrate streams.

  6. Assessment of analytical techniques for characterization of crystalline clopidogrel forms in patent applications

    Directory of Open Access Journals (Sweden)

    Luiz Marcelo Lira

    2014-04-01

    Full Text Available The aim of this study was to evaluate two important aspects of patent applications of crystalline forms of drugs: (i the physicochemical characterization of the crystalline forms; and (ii the procedure for preparing crystals of the blockbuster drug clopidogrel. To this end, searches were conducted using online patent databases. The results showed that: (i the majority of patent applications for clopidogrel crystalline forms failed to comply with proposed Brazilian Patent Office guidelines. This was primarily due to insufficient number of analytical techniques evaluating the crystalline phase. In addition, some patent applications lacked assessment of chemical/crystallography purity; (ii use of more than two analytical techniques is important; and (iii the crystallization procedure for clopidogrel bisulfate form II were irreproducible based on the procedure given in the patent application.

  7. Hydrogen peroxide maintains the heterogeneous reaction of sulfur dioxide on mineral dust proxy particles

    Science.gov (United States)

    Huang, Liubin; Zhao, Yue; Li, Huan; Chen, Zhongming

    2016-09-01

    The heterogeneous oxidation of sulfur dioxide (SO2) on α-Al2O3 particles was investigated using a flow reactor coupled with a transmission-Fourier transform infrared (T-FTIR) spectrometer at different relative humidities (RH) in the absence or presence of hydrogen peroxide (H2O2), with an emphasis on the saturation coverage of SO2 and the timescale on which the reaction reaches saturation. It is found that the saturation coverage of SO2 in the absence of H2O2 increases with rising RH due to the hydrolysis of SO2 by surface adsorbed water. However, the reaction ultimately reaches saturation since the produced sulfite/bisulfite cannot be further converted to sulfate/bisulfate in the absence of oxidants. In addition, the presence of H2O2 can significantly increase the saturation coverage of SO2 by efficiently oxidizing sulfite/bisulfite to sulfate/bisulfate. Under humid conditions, adsorbed water facilitates the hydrolysis of SO2 and mitigates the increase of surface acidity, which can inhibit the hydrolysis of SO2. Hence, in the presence of H2O2, the saturation coverage of SO2 as well as the time of reaction reaching saturation increases with rising RH and the surface is not saturated on the timescale of the experiments (40 h) at 60% RH. Furthermore, the increase of saturation coverage of SO2 in the presence of H2O2 was observed on chemically inactive SiO2 particles, indicating that the hydrolysis of SO2 and subsequent oxidation by H2O2 likely occurs on other types of particles. Our findings are of importance for understanding the role of water vapor and trace gases (e.g., H2O2) in the heterogeneous reaction of SO2 in the atmosphere.

  8. Laboratory scale studies on removal of chromium from industrial wastes

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Chromium being one of the major toxic pollutants is discharged from electroplating and chrome tanning processes and is also found in the effluents of dyes, paint pigments, manufacturing units etc. Chromium exists in aqueous systems in both trivalent (Cr 3+) and hexavalent (Cr 6+) forms. The hexavalent form is carcinogenic and toxic to aquatic life, whereas Cr3+ is however comparatively less toxic. This study was undertaken to investigate the total chromium removal from industrial effluents by chemical means in order to achieve the Pakistan NEQS level of 1 mg/L by the methods of reduction and precipitation. The study was conducted in four phases.In phase I, the optimum pH and cost effective reducing agent among the four popular commercial chemicals was selected. As a result, pH of 2 was found to be most suitable and sodium meta bisulfate was found to be the most cost effective reducing agent respectively. Phase II showed that lower dose of sodium meta bisulfate was sufficient to obtain 100 % efficiency in reducing Cr6+ to Cr3+, and it was noted that reaction time had no significance in the whole process. A design curve for reduction process was established which can act as a tool for treatment of industrial effluents.Phase III studies indicated the best pH was 8.5 for precipitation of Cr 3+ to chromium hydroxide by using lime. An efficiency of 100 % was achievable and a settling time of 30 minutes produced clear effluent. Finally in Phase IV actual waste samples from chrome tanning and electroplating industries, when precipitated at pH of 12 gave 100 % efficiency at a settling time of 30 minutes and confirmed that chemical means of reduction and precipitation is a feasible and viable solution for treating chromium wastes from industries.

  9. Comparative fasting bioavailability of two clopidogrel formulations in healthy Mediterranean volunteers: an in vitro–in vivo correlation

    Directory of Open Access Journals (Sweden)

    Zaid AN

    2015-04-01

    Full Text Available Abdel Naser Zaid,1 Rowa’ Al Ramahi,1 Rana Bustami,2 Ayman Mousa,3 Sewar Khasawneh2 1Department of Pharmacy, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine; 2Pharmaceutical Research Unit, Amman, Jordan; 3R&D Department, Middle East Pharmaceutical Industries Co Ltd, Riyadh, Saudi Arabia Objective: The aim of this study was to evaluate the bioequivalence of two drug products, generic clopidogrel bisulfate 75 mg film-coated tablets versus the reference Plavix® clopidogrel bisulfate 75 mg film-coated tablets.Methods: Bioequivalence of tablets was tested by comparisons against the reference brand product in accordance with the requirements of the Declaration of Helsinki, the current Good Clinical Practice Guidelines, and the International Conference on Harmonization.Results: The relationship between concentration and peak area ratio was found to be linear within the range 24.500–1,836.600 pg/mL for clopidogrel. The correlation coefficient (r was always greater than 0.99 during the course of the validation. Statistical comparison of the main pharmacokinetic parameters showed no significant difference between test and reference. The point estimates (ratios of geometric mean were 104.122%, 104.184%, and 109.091% for areas under the plasma concentration–time curve (AUC AUC0-last, AUC0-∞, and peak plasma concentration Cmax, respectively. These pharmacokinetic parameter values of clopidogrel and its main metabolite lie within the bioequivalence limit (80%–125% specified by the US Food and Drug Administration and the European Medicines Agency.Conclusion: The tested drug product was bioequivalent to the reference drug under fasting conditions and had the same safety profile, which is important to achieve equivalent therapeutic effect with the reference. Keywords: film coating, stability, clopidogrel, bioequivalence

  10. Effects of the physical state of tropospheric ammonium-sulfate-nitrate particles on global aerosol direct radiative forcing

    Directory of Open Access Journals (Sweden)

    S. T. Martin

    2004-01-01

    Full Text Available The effect of aqueous versus crystalline sulfate-nitrate-ammonium tropospheric particles on global aerosol direct radiative forcing is assessed. A global three-dimensional chemical transport model predicts sulfate, nitrate, and ammonium aerosol mass. An aerosol thermodynamics model is called twice, once for the upper side (US and once for lower side (LS of the hysteresis loop of particle phase. On the LS, the sulfate mass budget is 40% solid ammonium sulfate, 12% letovicite, 11% ammonium bisulfate, and 37% aqueous. The LS nitrate mass budget is 26% solid ammonium nitrate, 7% aqueous, and 67% gas-phase nitric acid release due to increased volatility upon crystallization. The LS ammonium budget is 45% solid ammonium sulfate, 10% letovicite, 6% ammonium bisulfate, 4% ammonium nitrate, 7% ammonia release due to increased volatility, and 28% aqueous. LS aerosol water mass partitions as 22% effloresced to the gas-phase and 78% remaining as aerosol mass. The predicted US/LS global fields of aerosol mass are employed in a Mie scattering model to generate global US/LS aerosol optical properties, including scattering efficiency, single scattering albedo, and asymmetry parameter. Global annual average LS optical depth and mass scattering efficiency are, respectively, 0.023 and 10.7 m2 (g SO4-2-1, which compare to US values of 0.030 and 13.9 m2 (g SO4-2-1. Radiative transport is computed, first for a base case having no aerosol and then for the two global fields corresponding to the US and LS of the hysteresis loop. Regional, global, seasonal, and annual averages of top-of-the-atmosphere aerosol radiative forcing on the LS and US (FL and FU, respectively, in W m-2 are calculated. Including both anthropogenic and natural emissions, we obtain global annual averages of FL=-0.750, FU=-0.930, and DFU,L=24% for full sky calculations without clouds and FL=-0.485, FU=-0.605, and DFU,L=25% when clouds are included. Regionally, DFU,L=48% over the USA, 55% over Europe

  11. 降血脂药非诺贝特的绿色合成%Green Synthesis of Hypolipidemic Drug Fenofibrate

    Institute of Scientific and Technical Information of China (English)

    李敢; 王德堂; 时光侠; 刘颖; 夏先伟; 肖先举

    2014-01-01

    The esterification of fenofibrate acid with isopropyl alcohol was studied with sodium bisulfate as catalyst and dimethylbenzene as water carrying agents.The effects of different factors such as mole ratio of reactants, catalyst dosage and amount of carrying agent on the yield of fenofibrate were investigated.The experimental results showed that sodium bisulfate monohydrate exhibited excellently catalytic activity.The optimum reaction conditions were found as follows:0.1 mol fenofibrate acid, mole ratio of isopropyl alcohol to fenofibrate acid was 3.5:1, the weight of the catalyst was 3.5 g, 40 mL dimethylbenzene, and refluxing reaction time was 30 min.Under these conditions, the yield of fenofibrate was up to 88.6%.The catalyst could be repeatedly used for five times without lossing its catalytic activity.The structure was characterized by IR.%以一水合硫酸氢钠为催化剂,二甲苯为带水剂,对非诺贝特酸与异丙醇的酯化反应进行了研究,考察了醇酸摩尔比、催化剂用量、带水剂用量等因素对非诺贝特产率的影响。结果表明:硫酸氢钠有着良好的催化活性,在非诺贝特酸用量0.1 mol, n(异丙醇):n(非诺贝特酸)=3.5:1,催化剂一水合硫酸氢钠用量3.5 g,二甲苯40 mL,反应时间3 h的条件下,非诺贝特产率可达88.6%,催化剂重复使用5次仍保持较高的活性,其结构经IR确证。

  12. Theoretical study on the reactivity of sulfate species with hydrocarbons

    Science.gov (United States)

    Ma, Q.; Ellis, G.S.; Amrani, A.; Zhang, T.; Tang, Y.

    2008-01-01

    The abiotic, thermochemically controlled reduction of sulfate to hydrogen sulfide coupled with the oxidation of hydrocarbons, is termed thermochemical sulfate reduction (TSR), and is an important alteration process that affects petroleum accumulations in nature. Although TSR is commonly observed in high-temperature carbonate reservoirs, it has proven difficult to simulate in the laboratory under conditions resembling nature. The present study was designed to evaluate the relative reactivities of various sulfate species in order to provide greater insight into the mechanism of TSR and potentially to fill the gap between laboratory experimental data and geological observations. Accordingly, quantum mechanics density functional theory (DFT) was used to determine the activation energy required to reach a potential transition state for various aqueous systems involving simple hydrocarbons and different sulfate species. The entire reaction process that results in the reduction of sulfate to sulfide is far too complex to be modeled entirely; therefore, we examined what is believed to be the rate limiting step, namely, the reduction of sulfate S(VI) to sulfite S(IV). The results of the study show that water-solvated sulfate anions SO42 - are very stable due to their symmetrical molecular structure and spherical electronic distributions. Consequently, in the absence of catalysis, the reactivity of SO42 - is expected to be extremely low. However, both the protonation of sulfate to form bisulfate anions (HSO4-) and the formation of metal-sulfate contact ion-pairs could effectively destabilize the sulfate molecular structure, thereby making it more reactive. Previous reports of experimental simulations of TSR generally have involved the use of acidic solutions that contain elevated concentrations of HSO4- relative to SO42 -. However, in formation waters typically encountered in petroleum reservoirs, the concentration of HSO4- is likely to be significantly lower than the levels

  13. Orbitrap mass spectrometry characterization of hybrid chondroitin/dermatan sulfate hexasaccharide domains expressed in brain.

    Science.gov (United States)

    Robu, Adrian C; Popescu, Laurentiu; Munteanu, Cristian V A; Seidler, Daniela G; Zamfir, Alina D

    2015-09-15

    In the central nervous system, chondroitin/dermatan sulfate (CS/DS) glycosaminoglycans (GAGs) modulate neurotrophic effects and glial cell maturation during brain development. Previous reports revealed that GAG composition could be responsible for CS/DS activities in brain. In this work, for the structural characterization of DS- and CS-rich domains in hybrid GAG chains extracted from neural tissue, we have developed an advanced approach based on high-resolution mass spectrometry (MS) using nanoelectrospray ionization Orbitrap in the negative ion mode. Our high-resolution MS and multistage MS approach was developed and applied to hexasaccharides obtained from 4- and 14-week-old mouse brains by GAG digestion with chondroitin B and in parallel with AC I lyase. The expression of DS- and CS-rich domains in the two tissues was assessed comparatively. The analyses indicated an age-related structural variability of the CS/DS motifs. The older brain was found to contain more structures and a higher sulfation of DS-rich regions, whereas the younger brain was found to be characterized by a higher sulfation of CS-rich regions. By multistage MS using collision-induced dissociation, we also demonstrated the incidence in mouse brain of an atypical [4,5-Δ-GlcAGalNAc(IdoAGalNAc)2], presenting a bisulfated CS disaccharide formed by 3-O-sulfate-4,5-Δ-GlcA and 6-O-sulfate-GalNAc moieties. PMID:26123275

  14. Raman spectroscopy of the system iron(III)-sulfuric acid-water: an approach to Tinto River's (Spain) hydrogeochemistry.

    Science.gov (United States)

    Sobron, P; Rull, F; Sobron, F; Sanz, A; Medina, J; Nielsen, C J

    2007-12-15

    Acid mine drainage is formed when pyrite (FeS(2)) is exposed and reacts with air and water to form sulfuric acid and dissolved iron. Tinto River (Huelva, Spain) is an example of this phenomenon. In this study, Raman spectroscopy has been used to investigate the speciation of the system iron(III)-sulfuric acid-water as an approach to Tinto River's aqueous solutions. The molalities of sulfuric acid (0.09 mol/kg) and iron(III) (0.01-1.5 mol/kg) were chosen to mimic the concentration of the species in Tinto River waters. Raman spectra of the solutions reveal a strong iron(III)-sulfate inner-sphere interaction through the nu(1) sulfate band at 981 cm(-1) and its shoulder at 1005 cm(-1). Iron(III)-sulfate interaction may also be facilitated by hydrogen bonds and monitored in the Raman spectra through the symmetric stretching band of bisulfate at 1052 cm(-1) and a shoulder at 1040 cm(-1). Other bands in the low-frequency region of the Raman spectra are attributed to the hydrogen-bonded complexes formation as well. PMID:17869164

  15. Effect of Organic Coatings, Humidity and Aerosol Acidity on Multiphase Chemistry of Isoprene Epoxydiols.

    Science.gov (United States)

    Riva, Matthieu; Bell, David M; Hansen, Anne-Maria Kaldal; Drozd, Greg T; Zhang, Zhenfa; Gold, Avram; Imre, Dan; Surratt, Jason D; Glasius, Marianne; Zelenyuk, Alla

    2016-06-01

    Multiphase chemistry of isomeric isoprene epoxydiols (IEPOX) has been shown to be the dominant source of isoprene-derived secondary organic aerosol (SOA). Recent studies have reported particles composed of ammonium bisulfate (ABS) mixed with model organics exhibit slower rates of IEPOX uptake. In the present study, we investigate the effect of atmospherically relevant organic coatings of α-pinene (AP) SOA on the reactive uptake of trans-β-IEPOX onto ABS particles under different conditions and coating thicknesses. Single particle mass spectrometry was used to characterize in real-time particle size, shape, density, and quantitative composition before and after reaction with IEPOX. We find that IEPOX uptake by pure sulfate particles is a volume-controlled process, which results in particles with uniform concentration of IEPOX-derived SOA across a wide range of sizes. Aerosol acidity was shown to enhance IEPOX-derived SOA formation, consistent with recent studies. The presence of water has a weaker impact on IEPOX-derived SOA yield, but significantly enhanced formation of 2-methyltetrols, consistent with offline filter analysis. In contrast, IEPOX uptake by ABS particles coated with AP-derived SOA is lower compared to that of pure ABS particles, strongly dependent on particle composition, and therefore on particle size. PMID:27176464

  16. The dissociation of oxy-acids at elevated temperatures

    International Nuclear Information System (INIS)

    The heat capacities of dissociation for carbonic, bicarbonate, phosphoric, biphosphate, silicic, nitric, boric and bisulfate oxy-acids have been evaluated at temperatures up to 300 C using published dissociation constants, heat capacities and a model which explicitly accounts for both electrostatic and nonelectrostatic contributions to the thermodynamic properties of dissociation. The heat capacities calculated are independent of the entropies of dissociation or the chemical characteristics of the acids, and are the same for all acids of a given dissociation type (i.e. 1st, 2nd, etc.). The average deviation between measured and calculated log Ksub(T)'s is less than 0.05 log units in the temperature range from 25 to 300 C. Dissociation constants for acetic acid can be accurately calculated using the oxy-acid heat capacity expression. The heat capacities are used to calculate dissociation constants for the oxy-acids of Cr(VI), N(III), S(IV), S(II), Se(IV), Se(VI), As(III), As(V), Te(VI), Cl(I), Cl(III), I(V) and C1-C3 aliphatic acids to temperatures of 300 C. (author)

  17. Estimating the NH3:H2SO4 ratio of nucleating clusters in atmospheric conditions using quantum chemical methods

    Directory of Open Access Journals (Sweden)

    M. Kulmala

    2007-05-01

    Full Text Available We study the ammonia addition reactions of H2SO4·NH3 molecular clusters containing up to four ammonia and two sulfuric acid molecules using the ab initio method RI-MP2 (Resolution of Identity 2nd order Møller-Plesset perturbation theory. Together with results from previous studies, we use the computed values to estimate an upper limit for the ammonia content of small atmospheric clusters, without having to explicitly include water molecules in the quantum chemical simulations. Our results indicate that the NH3:H2SO4 mole ratio of small molecular clusters in typical atmospheric conditions is probably around 1:2. High ammonia concentrations or low temperatures may lead to the formation of ammonium bisulfate (1:1 clusters, but our results rule out the formation of ammonium sulfate clusters (2:1 anywhere in the atmosphere. A sensitivity analysis indicates that the qualitative conclusions of this study are not affected even by relatively large errors in the calculation of electronic energies or vibrational frequencies.

  18. Bifunctional Crosslinking Agents Enhance Anion Exchange Membrane Efficacy for Vanadium Redox Flow Batteries.

    Science.gov (United States)

    Wang, Wenpin; Xu, Min; Wang, Shubo; Xie, Xiaofeng; Lv, Yafei; Ramani, Vijay K

    2014-06-01

    A series of cross-linked fluorinated poly (aryl ether oxadiazole) membranes (FPAEOM) derivatized with imidazolium groups were prepared. Poly (N-vinylimidazole) (PVI) was used as the bifunctional cross-linking agent to: a) lower vanadium permeability, b) enhance dimensional stability, and c) concomitantly provide added ion exchange capacity in the resultant anion exchange membranes. At a molar ratio of PVI to FPAEOM of 1.5, the resultant membrane (FPAEOM-1.5 PVI) had an ion exchange capacity of 2.2 meq g-1, a vanadium permeability of 6.8×10-7 cm2 min-1, a water uptake of 68 wt.%, and an ionic conductivity of 22.0 mS cm-1, all at 25°C. Single cells prepared with the FPAEOM-1.5 PVI membrane exhibited a higher coulombic efficiency (> 92%) and energy efficiency (> 86%) after 40 test cycles in vanadium redox flow battery. The imidazolium cation showed high chemical stability in highly acidic and oxidizing vanadium solution as opposed to poor stability in alkaline solutions. Based on our DFT studies, this was attributed to the lower HOMO energy (-7.265 eV) of the HSO4- ion (compared to the OH- ion; -5.496 eV) and the larger HOMO-LUMO energy gap (6.394 eV) of dimethylimidazolium bisulfate ([DMIM] [HSO4]) as compared to [DMIM] [OH] (5.387 eV). PMID:24884171

  19. Impacts of Sulfate Seed Acidity and Water Content on Isoprene Secondary Organic Aerosol Formation.

    Science.gov (United States)

    Wong, Jenny P S; Lee, Alex K Y; Abbatt, Jonathan P D

    2015-11-17

    The effects of particle-phase water and the acidity of pre-existing sulfate seed particles on the formation of isoprene secondary organic aerosol (SOA) was investigated. SOA was generated from the photo-oxidation of isoprene in a flow tube reactor at 70% relative humidity (RH) and room temperature in the presence of three different sulfate seeds (effloresced and deliquesced ammonium sulfate and ammonium bisulfate) under low NOx conditions. High OH exposure conditions lead to little isoprene epoxydiol (IEPOX) SOA being generated. The primary result is that particle-phase water had the largest effect on the amount of SOA formed, with 60% more SOA formation occurring with deliquesced ammonium sulfate seeds as compared to that on effloresced ones. The additional organic material was highly oxidized. Although the amount of SOA formed did not exhibit a dependence on the range of seed particle acidity examined, perhaps because of the low amount of IEPOX SOA, the levels of high-molecular-weight material increased with acidity. While the uptake of organics was partially reversible under drying, the results nevertheless indicate that particle-phase water enhanced the amount of organic aerosol material formed and that the RH cycling of sulfate particles may mediate the extent of isoprene SOA formation in the atmosphere. PMID:26460477

  20. Differential elimination of radioiodine from single- and double-stranded 125I-DNA

    International Nuclear Information System (INIS)

    [125I]Iododeoxyuridyl residues in heat-denatured I-DNA underwent deiodination in solutions of sodium bisulfite. In 0.5 M bisulfite containing 1 M trimethylamine, 92% of the iodine was released from denatured DNA in 2.5 min at 60oC. By contrast iodine in native I-DNA remained stably bound under the same condition. The deiodination of [125I]I-deoxyuridine residues incorporated by enzymatic copying of oligomers 60 nucleotides in length was found to be pairing dependent. While 125I in iododeoxyuridine paired to deoxyadenosine in a complementary oligomer remained ≅ 90% covalently bound in the presence of 1 M bisulfate at 60oC, when the iodouridylate residue wa mismatched > 96% was eliminated in 4 min. The presence of mismatches in the two nucleotides adjacent to a [125I]iododeoxyuridine/deoxyadenosine pair increased the elimination of iodine. The results indicate that the deiodination reaction might be applied for the rapid detection of variations in natural DNA sequences. (author)

  1. A comparative study on toxicity identification of industrial effluents using Daphnia magna.

    Science.gov (United States)

    Yi, Xianliang; Kim, Eunhee; Jo, Hun-Je; Han, Taejun; Jung, Jinho

    2011-09-01

    In this study, acute toxicity monitoring and toxicity identification evaluation procedures were applied to identify causative toxicants in industrial effluents. Effluents from a metal plating factory and a rubber products factory were acutely toxic toward Daphnia magna and the toxicity varied over different sampling events (2.9-5.9 and 1.7-7.6 TU, respectively). For the rubber products effluent, it was confirmed that zinc (5.65-13.18 mg L(-1)) was found to be a major cause of toxicity, which is likely originated from zinc 2-mercaptobenzothiazole and zinc diethyldithiocarbamate used as vulcanization accelerators. For the metal plating effluent, it appeared that the presence of high concentrations of Cl(-) and SO(4)(2-) (8,539-11,400 and 3,588-4,850 mg L(-1), respectively) caused the observed toxicity. These toxicants likely originated from sodium bisulfate (NaHSO(3)) and sodium hypochlorite (NaOCl) used as reducing and oxidizing agents. Though copper was found to be present in levels much higher than the EC(50) (50% effective concentration) value, this was not attributable to the toxicity of metal plating effluent likely due to complexation with dissolved organic matter. PMID:21761172

  2. Evaluation of chemical amendments to reduce ammonia volatilization from poultry litter.

    Science.gov (United States)

    Moore, P A; Daniel, T C; Edwards, D R; Miller, D M

    1996-03-01

    Ammonia volatilization from poultry litter often causes high levels of atmospheric ammonia in poultry houses, which is detrimental to both farm workers and birds. Ammonia emissions from houses also aggravate environmental problems, such as acid rain, and result in a loss of fertilizer nitrogen. The objectives of this study were to determine the effect of litter amendments on ammonia volatilization and to determine the effect of these amendments on nitrogen and phosphorus content in litter. The results of this research indicate that alum [Al2(SO4)3.18H2O], ferrous sulfate (FeSO4.7H2O), and phosphoric acid (H3PO4) dramatically reduce ammonia volatilization form litter. The amount of ammonia lost from litter treated with sodium bisulfate (NaHSO4) and a proprietory product made of Ca-Fe silicate with a phosphoric acid coating was not different from the control (untreated litter). Aluminum sulfate (alum) and ferrous sulfate also reduced water soluble P concentrations in litter, whereas phosphoric acid greatly increased water-soluble P levels. The most effective compound evaluated with respect to reducing both ammonia loss and P solubility was alum. PMID:8778722

  3. A method for detecting the presence of organic fraction in nucleation mode sized particles

    Directory of Open Access Journals (Sweden)

    P. Vaattovaara

    2005-06-01

    Full Text Available New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, d<20 nm and the lower end of Aitken mode particles (d≤50 nm is still insufficient. In this work, we have applied the UFO-TDMA (ultrafine organic tandem differential mobility analyzer method to shed light on the presence of organic fraction in the nucleation mode size class in different atmospheric environments. The basic principle of the organic fraction detection is based on our laboratory UFO-TDMA measurements with organic and inorganic compounds. Our laboratory measurements indicate that the usefulness of the UFO-TDMA in the field experiments would arise especially from the fact that atmospherically the most relevant inorganic compounds do not grow in subsaturated ethanol vapor, when particle size is 10nm in diameter and saturation ratio is about 86% or below it. Furthermore, internally mixed particles composed of ammonium bisulfate and sulfuric acid with sulfuric acid mass fraction ≤33% show no growth at 85% saturation ratio. In contrast, 10 nm particles composed of various organic compounds of atmospheric relevance are able to grow in those conditions. These discoveries indicate that it is possible to detect the presence of organics in atmospheric nucleation mode sized particles using the UFO-TDMA method. In the future, the UFO-TDMA is expected to be an important aid to describe the composition of atmospheric newly-formed particles.

  4. A method for detecting the presence of organic fraction in nucleation mode sized particles

    Directory of Open Access Journals (Sweden)

    P. Vaattovaara

    2005-01-01

    Full Text Available New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, d<20 nm and the lower end of Aitken mode particles (d≤50 nm is still insufficient. In this work, we have applied the UFO-TDMA (ultrafine organic tandem differential mobility analyzer method to shed light on the presence of an organic fraction in the nucleation mode size class in different atmospheric environments. The basic principle of the organic fraction detection is based on our laboratory UFO-TDMA measurements with organic and inorganic compounds. Our laboratory measurements indicate that the usefulness of the UFO-TDMA in the field experiments would arise especially from the fact that atmospherically the most relevant inorganic compounds do not grow in subsaturated ethanol vapor, when particle size is 10 nm in diameter and saturation ratio is about 86% or below it. Furthermore, internally mixed particles composed of ammonium bisulfate and sulfuric acid with sulfuric acid mass fraction ≤33% show no growth at 85% saturation ratio. In contrast, 10 nm particles composed of various oxidized organic compounds of atmospheric relevance are able to grow in those conditions. These discoveries indicate that it is possible to detect the presence of organics in atmospheric nucleation mode sized particles using the UFO-TDMA method. In the future, the UFO-TDMA is expected to be an important aid to describe the composition of atmospheric newly-formed particles.

  5. Synthesis of thiol-functionalized spent grain as a novel adsorbent for divalent metal ions.

    Science.gov (United States)

    Chai, Liyuan; Li, Qingzhu; Zhu, Yonghua; Zhang, Zhiyuan; Wang, Qingwei; Wang, Yunyan; Yang, Zhihui

    2010-08-01

    Spent grain (SG) was functionalized with thioglycolic acid in N,N-dimethylformamide (DMF) medium using sodium bisulfate monohydrate (NaHSO(4).H(2)O) as a catalyst, followed by treatment with sodium sulfide nonahydrate (Na(2)S.9H(2)O). Characterization of thiol-functionalized spent grain (TFSG) was performed using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. These analytical results revealed the emergence of S-H and C=O groups after the chemical modification, indicating that thiol groups were successfully grafted onto TFSG. As compared with SG, TFSG showed significant improvement in terms of metal loading capacity. Typically, adsorption capacity for Zn(2+) was increased from 125.76 mg g(-1) of SG to 227.37 mg g(-1) of TFSG, which was confirmed by X-ray fluorescence (XRF) analysis. This increase may be attributed to both the formation of ester linkage and the grafting of thiol groups onto TFSG. The experimental results indicate that TFSG is a promising adsorbent for removal heavy metals from contaminated water. PMID:20338755

  6. Size-Resolved Volatility and Chemical Composition of Aged European Aerosol Measured During FAME-2008

    Science.gov (United States)

    Hildebrandt, L.; Mohr, C.; Lee, B.; Engelhart, G. J.; Decarlo, P. F.; Prevot, A. S.; Baltensperger, U.; Donahue, N. M.; Pandis, S. N.

    2008-12-01

    We present first results on the volatility and chemical composition of aged organic aerosol measured during the Finokalia Aerosol Measurement Experiment - 2008 (FAME-2008). Finokalia is located in the Southeast of Crete, Greece, and this remote site allows for the measurement of aged European aerosol as it is transported from Central to Southeastern Europe. We measured the volatility of the aerosol at Finokalia as a function of its size by combining several instruments. We used an Aerodyne quadrupole aerosol mass spectrometer (Q-AMS) to measure the size-resolved chemical composition of the particles, a scanning mobility particle sizer (SMPS) to measure the volume distribution of particles, and a thermodenuder system to induce changes in size and composition via moderate heating of the particles. The largest fraction of the non-refractory material in the aerosol sampled was ammonium sulfate and ammonium bisulfate, followed by organic material and a small contribution from nitrate. Most of the organic aerosol was highly oxidized, even after only a few days of transport over continental Europe. These highly oxidized organics had lower volatility than fresh primary or secondary aerosol measured in the laboratory. Significant changes in air-parcel trajectories and wind direction led to changes in the chemical composition of the sampled aerosol and corresponding changes of the volatility. These results allow the quantification of the effect of atmospheric processing on organic aerosol volatility and can be used as constraints for atmospheric Chemical Transport Models that predict the aerosol volatility.

  7. Technology research on the preparation of fosfomycin trometamol from fosfomycin sodium%磷霉素钠制备磷霉素氨丁三醇的工艺研究

    Institute of Scientific and Technical Information of China (English)

    黄晨; 严晶; 丁一刚; 王超

    2015-01-01

    Objective to investigate a new synthesis for the preparation of fosfomycin tromethamine and to seek for the opti‐mized process and crystallization conditions .Methods An inorganic method ,utilizing in situ generated tromethamine bisulfate to re‐act with fosfomycin sodium was used to gain fosfomycin tromethamine .Results After the optimization of reaction and crystalliza‐tion condition ,it can produce fosfomycin tromethamine .Conclusion Inorganic acid salt synthesis technology is feasible with high yield .%目的:采用新型合成法制备磷霉素氨丁三醇,研究其合成工艺条件和析晶条件。方法无机酸式盐法,以磷霉素钠与氨丁三醇和硫酸的混合酸式盐进行中和反应制得磷霉素氨丁三醇。结果优化反应和结晶条件后可生成磷霉素氨丁三醇。结论无机酸式盐法合成工艺可行,收率高。

  8. Understanding Persulfate Production at Boron Doped Diamond Film Anodes

    International Nuclear Information System (INIS)

    This research used molecular modeling and rotating disk electrode experiments (RDE) to investigate possible reaction pathways for persulfate production via electrolysis of sulfuric acid solutions using boron doped diamond (BDD) film anodes. Density functional theory (DFT) modeling indicated that uncatalyzed oxidation of SO42− and HSO4− occurs at lower potentials than water oxidation, and that sulfate radical species (SO4−• and HSO4• ) may be produced via direct electron transfer, or via reaction with hydroxyl radicals. The RDE experiments indicated that rates of persulfate generation were strongly dependent of the condition of the electrode surface, and that aged electrode surfaces favored water oxidation over direct SO42− and HSO4− oxidation. Combination of sulfate radical species in solution is the lowest energy pathway for persulfate production. Sulfate radical species may also react with radical sites on the electrode surface and produce chemisorbed intermediates that can stabilize sulfate radical species. Reaction of the chemisorbed intermediates with a bisulfate radical can produce persulfate via a surface catalyzed pathway. However, the activation barriers for this pathway are much higher than those for persulfate production via solution phase species

  9. Quality engineering and control. Semiannual progress report, May-October 1978

    International Nuclear Information System (INIS)

    The standard colorimetric procedure for thorium was improved by using lanthanum carrier precipitation of thorium fluoride, conversion to sulfate, and colorimetric measurement with thoron. Four types of anion-exchange resins were evaluated using breakthrough capacity, elution volume, and the neptunium-plutonium ratios in both wash solutions and ion-column eluates as criteria, and 100 to 200 mesh Dowex 1 x 4 resin had the most favorable separation characteristics. Use of commercially available aqueous cleaner followed by water and acetone rinses was found to be superior to other techniques for cleaning uranium samples prior to carbon analysis. The substitution of sodium bisulfate for potassium pyrosulfate in the fusion procedure has lead to a more efficient dissolution process for oxide samples undergoing plutonium assay and the determination of uranium impurities. Sealed-capillary differential thermal analysis experiments were performed to assess the relative reactivities of iron, stainless steel, copper, beryllium, aluminum, and plutonium with trichloroethylene, methyl chloroform, and Freon TF. Results obtained by a method involving reduction of plutonium with titanium (III) chloride followed by titration with standard cerium (IV) sulfate solution are comparable to those obtained by an established amperometric-titration method

  10. Characterization of commercial expandable graphite fire retardants

    International Nuclear Information System (INIS)

    Highlights: • Expandable graphite is less well-ordered than its graphite bisulfate progenitor. • It includes graphite oxide as a randomly interstratified phase. • CO2, CO and SO2 are released during thermal-driven exfoliation. - Abstract: Thermal analysis and other techniques were employed to characterize two expandable graphite samples. The expansion onset temperatures of the expandable graphite's were ca. 220 °C and 300 °C respectively. The key finding is that the commercial products are not just pure graphite intercalation compounds with sulfuric acid species intercalated as guest ions and molecules in between intact graphene layers. A more realistic model is proposed where graphite oxide-like layers are also randomly interstratified in the graphite flakes. These graphite oxide-like layers comprise highly oxidized graphene sheets which contain many different oxygen-containing functional groups. This model explains the high oxygen to sulfur atomic ratios found in both elemental analysis of the neat materials and in the gas generated during the main exfoliation event

  11. Research on various factors influencing the moisture absorption property of sodium polyacrylate

    Institute of Scientific and Technical Information of China (English)

    ZHANG ChunXiao; ZHANG WanXi; PAN ZhenYuan; ZHANG XiYao; LIU Jian; YUE ChongWang

    2009-01-01

    Sodium polyacrylate was synthesized with acrylic acid as the monomer,and sodium bisulfate and ammonium persulfate as the initiator,by means of aqueous solution polymerization.The factors influencing the properties of moisture absorption,such as monomer concentration,dosage of initiator,and reaction temperature were systematically investigated.The experimental results indicate that the moisture-absorbing property of this polymer was better than other traditional material,such as silica gel,and molecular sieve.The best reaction condition and formula are based on the orthogonal experiment design.The optimum moisture absorbency of sodium polyacrylate reaches 1.01 g/g.The mathematical correlation of this polymer with various factors and moisture absorbency is obtained based on the multiple regression analysis.The moisture content intuitive analysis table shows that neutralization degree has the most significant influence on moisture absorbency,followed by monomer concentration and reaction temperature,while other factors have less influence.

  12. Preparation of the Plywood Using UF Resin Modified with Blocked Isocyanate as Bonding Agent%封闭异氰酸酯改性脲醛树脂制备胶合板

    Institute of Scientific and Technical Information of China (English)

    张彦华; 顾继友; 谭海彦; 李炜

    2009-01-01

    采用亚硫酸氢钠封闭异氰酸酯改性UF树脂制备胶合板,研究了制板用混合胶液的比例、热压时间、热压温度等热压工艺对胶合板性能的影响,结果表明,在UF/PAPI=100/10、热压温度为110℃、热压时间为4min时,所制备胶合板的甲醛释放量达到国家标准,并且具有较高的胶合性能.%The plywood was prepared using the UF resin modified with isocyanate blocked by sodium bisul-fate as adhesive. And the effects of the ratio of UF resin to isocyanate, hot press temperature, hot pre ss timeon the properties of the plywood were also studied. The results showed that under the conditions of UF/PAPI =100/10, hot press temperature of 110℃and hot press time of 4min, the bonding strength of the plywood was improved obviously and the formaldehyde release from the plywood could meet the requirements specified in national standard.

  13. Proteomic identification of mitochondrial targets involved in andrographolide sodium bisulfite-induced nephrotoxicity in a rat model.

    Science.gov (United States)

    Xing, Wen Min; Yuan, Tang Juan; Xu, Jia Dong; Gu, Li Li; Liang, Pei; Lu, Hong

    2015-09-01

    Our previous works have indicated that the mitochondrion is the primary target of nephrotoxicity induced by andrographolide sodium bisulfate (ASB), but the mechanisms of ASB-induced nephrotoxicity have remained largely unknown. In this study, proteomic analysis was used to explore the changes in the renal mitochondrial proteome in SD rats after treatment with ASB. SD rats were intraperitoneally administered with ASB (100, 600mg/kg/d) for 7 days. Renal impairment was evaluated by pathological observation. Two-dimensional gel electrophoresis (2-DE), as well as matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS), was applied for the identification of mitochondrial protein and was validated by Western blotting. Protein-protein interactions were analyzed using a Web-based bioinformatics tool (STRING, version 9.1). Rat kidneys exhibited histopathological changes after treatment with ASB, and 13 proteins were significantly changed, including ES1 protein homolog, heat shock cognate 71kDa protein, peroxiredoxin-1 (Prdx1), cytochrome C oxidase subunit 5B (COX5B), prohibitin (PHB), threonine-tRNA ligase, pyruvate dehydrogenase E1 component subunit beta (PDH-β), voltage-dependent anion-selective channel protein 2 (VDAC2), voltage-dependent anion-selective channel protein 1 (VDAC1), adenylate kinase 2 (KAD2) and others. These data demonstrated that the expression levels of several proteins significantly changed in the mitochondria, and these proteins could be candidate biomarkers for ASB-induced nephrotoxicity. PMID:26356389

  14. Andrographolide-induced apoptosis in human renal tubular epithelial cells: Roles of endoplasmic reticulum stress and inflammatory response.

    Science.gov (United States)

    Gu, Li-Li; Zhang, Xin-Yue; Xing, Wen-Min; Xu, Jia-Dong; Lu, Hong

    2016-07-01

    Andrographolide sodium bisulfate as a kind of soluble derivative of andrographolide (AD), is obviously known to be nephrotoxicity, but AD has not been reported clearly. Our study aimed to investigate the induction of apoptosis in human renal tubular epithelial (HK-2) cells by AD and its possible mechanism. Our results demonstrated that AD (0-250μmol/L) inhibited Hk-2 cells proliferation in a dose- and time-dependent manner and induced apoptosis, accompanied by decreased of superoxide dismutase (SOD) activity and increased of malondialdehvde (MDA) content. Simultaneously, AD regulated the expression of endoplasmic reticulum (ER) molecular chaperone glucose-regulated protein 78 (GRP78/Bip) protein, elevated the expressions of C/EBP homologous protein (CHOP) and Caspase-4, indicating activation of ER stress signaling, and induced the alterative expression of kidney injury molecule-1 (KIM-1), tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6) proteins. It provided evidence that ER stress and inflammation would be significant mechanisms responsible for AD-induced apoptosis in addition to oxidative stress. PMID:27344125

  15. Standard practice for preparation and dissolution of plutonium materials for analysis

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This practice is a compilation of dissolution techniques for plutonium materials that are applicable to the test methods used for characterizing these materials. Dissolution treatments for the major plutonium materials assayed for plutonium or analyzed for other components are listed. Aliquants of the dissolved samples are dispensed on a weight basis when one of the analyses must be highly reliable, such as plutonium assay; otherwise they are dispensed on a volume basis. 1.2 The treatments, in order of presentation, are as follows: Procedure Title Section Dissolution of Plutonium Metal with Hydrochloric Acid 9.1 Dissolution of Plutonium Metal with Sulfuric Acid 9.2 Dissolution of Plutonium Oxide and Uranium-Plutonium Mixed Oxide by the Sealed-Reflux Technique 9.3 Dissolution of Plutonium Oxide and Uranium-Plutonium Mixed Oxides by Sodium Bisulfate Fusion 9.4 Dissolution of Uranium-Plutonium Mixed Oxides and Low-Fired Plutonium Oxide in Beakers 9.5 1.3 The values stated in SI units are to be re...

  16. Evaluating Chemical Mitigation of Salmonella Typhimurium ATCC 14028 in Animal Feed Ingredients.

    Science.gov (United States)

    Cochrane, Roger A; Huss, Anne R; Aldrich, Gregory C; Stark, Charles R; Jones, Cassandra K

    2016-04-01

    Salmonella Typhimurium is a potential feed safety hazard in animal feed ingredients. Thermal mitigation of Salmonella spp. during rendering is effective but does not eliminate the potential for cross-contamination. Therefore, the objective of this experiment was to evaluate the effectiveness of chemicals to mitigate postrendering Salmonella Typhimurium ATCC 14028 contamination in rendered proteins over time. Treatments were arranged in a 6 × 4 factorial with six chemical treatments and four rendered protein meals. The chemical treatments included (i) control without chemical treatment, (ii) 0.3% commercial formaldehyde product, (iii) 2% essential oil blend, (iv) 2% medium chain fatty acid blend, (v) 3% organic acid blend, and (vi) 1% sodium bisulfate. The four rendered protein meals included (i) feather meal, (ii) blood meal, (iii) meat and bone meal, and (iv) poultry by-product meal. After matrices were chemically treated, they were inoculated with Salmonella Typhimurium ATCC 14028, stored at room temperature, and enumerated via plate counts on days 0, 1, 3, 7, 14, 21, and 42 postinoculation. The Salmonella concentration in ingredients treated with medium chain fatty acid and commercial formaldehyde were similar to one another (P = 0.23) but were 2 log lower than the control (P organic acids and essential oils also had lower Salmonella concentrations than the control (P poultry by-product meal (P acids or a commercial formaldehyde product were most effective at mitigating Salmonella Typhimurium ATCC 14028 in rendered protein meals. PMID:27052874

  17. DNA demethylation in the PTEN gene promoter induced by 5-azacytidine activates PTEN expression in the MG-63 human osteosarcoma cell line.

    Science.gov (United States)

    Song, Deye; Ni, Jiangdong; Xie, Hongming; Ding, Muliang; Wang, Jun

    2014-05-01

    This study used the MG-63 osteosarcoma cell line to investigate the demethylation of the phosphate and tension homolog (PTEN) gene promoter and the change in PTEN gene expression levels, which are caused by the methylation inhibitor 5-azacytidine (5-Zac), and the association between the two. Different concentrations of 5-Zac (0, 5 and 10 μmol/l) were added into the MG-63 cell culture medium and the cells were cultured for 72 h. The following techniques were performed on the cells: Western blot analysis to detect the PTEN protein; reverse transcription-polymerase chain reaction (PCR) to detect the mRNA transcription levels of the PTEN gene; flow cytometry to detect the cell apoptotic rate; and sodium bisulfate to deal with the DNA of each group. The genes of the PTEN promoter and the transcription factors specificity protein 1 (Sp1) and Myc were PCR amplified and transformed into Escherichia coli, then a number of clones were selected for sequencing and the methylation status of the amplified PTEN promoter fragment was detected. Following culture of the MG-63 cells with 5-Zac at concentrations of 0, 5 and 10 μmol/l for 72 h, the expression levels of PTEN protein in each group were gradually increased, presenting a concentration-dependent effect: Group 0 μmol/l compared with groups 5 and 10 μmol/l, P<0.05; and group 5 μmol/l compared with group 10 μmol/l, P=0.007. The mRNA expression levels of the PTEN gene significantly increased. The apoptotic rates of groups 0, 5 and 10 μmol/l were 0.69±0.42, 2.50±0.30 and 6.59±0.62%, and significant differences (P<0.01) were observed between every two groups. The bisulfate DNA sequencing results of three groups showed that, following the treatment with 5-Zac, the binding of the CG site to transcription factors was affected by demethylation. The average rate of demethylation indicated a statistical difference among the three groups. In conclusion, the methylation inhibitor 5-Zac leads to a significant increase in the

  18. DNA demethylation in the PTEN gene promoter induced by 5-azacytidine activates PTEN expression in the MG-63 human osteosarcoma cell line

    Science.gov (United States)

    SONG, DEYE; NI, JIANGDONG; XIE, HONGMING; DING, MULIANG; WANG, JUN

    2014-01-01

    This study used the MG-63 osteosarcoma cell line to investigate the demethylation of the phosphate and tension homolog (PTEN) gene promoter and the change in PTEN gene expression levels, which are caused by the methylation inhibitor 5-azacytidine (5-Zac), and the association between the two. Different concentrations of 5-Zac (0, 5 and 10 μmol/l) were added into the MG-63 cell culture medium and the cells were cultured for 72 h. The following techniques were performed on the cells: Western blot analysis to detect the PTEN protein; reverse transcription-polymerase chain reaction (PCR) to detect the mRNA transcription levels of the PTEN gene; flow cytometry to detect the cell apoptotic rate; and sodium bisulfate to deal with the DNA of each group. The genes of the PTEN promoter and the transcription factors specificity protein 1 (Sp1) and Myc were PCR amplified and transformed into Escherichia coli, then a number of clones were selected for sequencing and the methylation status of the amplified PTEN promoter fragment was detected. Following culture of the MG-63 cells with 5-Zac at concentrations of 0, 5 and 10 μmol/l for 72 h, the expression levels of PTEN protein in each group were gradually increased, presenting a concentration-dependent effect: Group 0 μmol/l compared with groups 5 and 10 μmol/l, P<0.05; and group 5 μmol/l compared with group 10 μmol/l, P=0.007. The mRNA expression levels of the PTEN gene significantly increased. The apoptotic rates of groups 0, 5 and 10 μmol/l were 0.69±0.42, 2.50±0.30 and 6.59±0.62%, and significant differences (P<0.01) were observed between every two groups. The bisulfate DNA sequencing results of three groups showed that, following the treatment with 5-Zac, the binding of the CG site to transcription factors was affected by demethylation. The average rate of demethylation indicated a statistical difference among the three groups. In conclusion, the methylation inhibitor 5-Zac leads to a significant increase in the

  19. 乳酸异十三酯的合成%Synthesis of Iso-tridecyl Lactate

    Institute of Scientific and Technical Information of China (English)

    卢峰; 招丽萍

    2013-01-01

    Using potassium bisulphate as a catalyst and cyclohexane as a co-boiling reagent, the iso-tridecyl lactate, one of emulsifiers in cosmetics, was synthesized via direct esterification of lactic acid and iso-tridecanol. The structure of objective product was confirmed by characterization with Fourier transform infrared spectrum (FTIR) and GC-MS. The result showed that the potassium bisulphate was suited to synthesize iso-tridecyl lactate. When the amount of potassium bisulfate added was 1 % of the gross mass, mole ratio of lactic acid to iso-tridecanol was 1.7, the amount of cyclohexane was 30 ml and reaction time was 4 h, the high conversion of iso-tridecanol of 91.77 % could be achieved.%  文章以乳酸和异十三醇为原料,直接酯化合成了乳酸异十三酯,考察了催化剂、酸醇比、带水剂的用量和反应时间对转化率的影响,通过红外光谱和气质联用仪对产品进行了结构表征。实验证明,硫酸氢钾具有较高的催化活性,最佳反应条件为:硫酸氢钾用量为乳酸和异十三醇总量的1%,带水剂用量为30 mL,乳酸和异十三醇的摩尔比为1.7∶1,反应时间为4 h,异十三醇转化率达91.77%。

  20. System for disposing of radioactive waste

    International Nuclear Information System (INIS)

    A system is described for disposing of radioactive waste material from nuclear reactors by solidifying the liquid components to produce an encapsulated mass adapted for disposal by burial. The method contemplates mixing of radioactive waste materials, with or without contained solids, with a setting agent capable of solidifying the waste liquids into a free standing hardened mass, placing the resulting liquid mixture in a container with a proportionate amount of a curing agent to effect solidification under controlled conditions, and thereafter burying the container and contained solidified mixture. The setting agent is a water-extendable polymer consisting of a suspension of partially polymerized particles of urea formaldehyde in water, and the curing agent is sodium bisulfate. Methods are disclosed for dewatering slurry-like mixtures of liquid and particulate radioactive waste materials, such as spent ion exchange resin beads, and for effecting desired distribution of non-liquid radioactive materials in the central area of the container prior to solidification, so that the surrounding mass of lower specific radioactivity acts as a partial shield against higher radioactivity of the non-liquid radioactive materials. The methods also provide for addition of non-radioactive filler materials to dilute the mixture and lower the overall radioactivity of the hardened mixture to desired Lowest Specific Activity counts. An inhibiting agent is added to the liquid mixture to adjust the solidification time, and provision is made for adding additional amounts of setting agent and curing agent to take up any free water and further encapsulate the hardened material within the container

  1. Comparison of a solid SMEDDS and solid dispersion for enhanced stability and bioavailability of clopidogrel napadisilate.

    Science.gov (United States)

    Kim, Dong Wuk; Kwon, Min Seok; Yousaf, Abid Mehmood; Balakrishnan, Prabagar; Park, Jong Hyuck; Kim, Dong Shik; Lee, Beom-Jin; Park, Young Joon; Yong, Chul Soon; Kim, Jong Oh; Choi, Han-Gon

    2014-12-19

    The intention of this study was to compare the physicochemical properties, stability and bioavailability of a clopidogrel napadisilate (CN)-loaded solid dispersion (SD) and solid self-microemulsifying drug delivery system (solid SMEDDS). SD was prepared by a surface attached method using different ratios of Cremophor RH60 (surfactant) and HPMC (polymer), optimized based on their drug solubility. Liquid SMEDDS was composed of oil (peceol), a surfactant (Cremophor RH60) and a co-surfactant (Transcutol HP). A pseudo-ternary phase diagram was constructed to identify the emulsifying domain, and the optimized liquid SMEDDS was spray dried with an inert solid carrier (silicon dioxide), producing the solid SMEDDS. The physicochemical properties, solubility, dissolution, stability and pharmacokinetics were assessed and compared to clopidogrel napadisilate (CN) and bisulfate (CB) powders. In solid SMEDDS, liquid SMEDDS was absorbed or coated inside the pores of silicon dioxide. In SD, hydrophilic polymer and surfactants were adhered onto drug surface. The drug was in crystalline and molecularly dispersed form in SD and solid SMEDDS, respectively. Solid SMEDDS and SD greatly increased the solubility of CN but gave lower drug solubility compared to CB powder. These preparations significantly improved the dissolution of CN, but the latter more increased than the former. Stability under accelerated condition showed that they were more stable compared to CB powder, and SD was more stable than solid SMEDDS. They significantly increased the oral bioavailability of CN powder. Furthermore, SD showed significantly improved oral bioavailability compared to solid SMEDDS and CB powder. Thus, SD with excellent stability and bioavailability is recommended as an alternative for the clopidogrel-based oral formulation. PMID:25263903

  2. System for disposing of radioactive waste

    International Nuclear Information System (INIS)

    A system is described for disposing of radioactive waste material from nuclear reactors by solidifying the liquid components to produce an encapsulated mass adapted for disposal by burial. The method contemplates mixing of radioactive waste materials, with or without contained solids, with a setting agent capable of solidifying the waste liquids into a free standing hardened mass, placing the resulting liquid mixture in a container with a proportionate amount of a curing agent to effect solidification under controlled conditions, and thereafter burying the container and contained solidified mixture. The setting agent is a water-extendable polymer consisting of a suspension of partially polymerized particles of urea formaldehyde in water, and the curing agent is sodium bisulfate. Methods are disclosed for dewatering slurry-like mixtures of liquid and particulate radioactive waste materials, such as spent ion exchange resin beads, and for effecting desired distribution of non-liquid radioactive materials in the central area of the container prior to solidification, so that the surrounding mass of lower specific radioactivity acts as a partial shield against higher radioactivity of the non-liquid radioactive materials. The methods also provide for addition of non-radioactive filler materials to dilute the mixture and lower the overall radioactivity of the hardened mixture to desired Lowest Specific Activity counts. An inhibiting agent is added to the liquid mixture to adjust the solidification time, and provision is made for adding additional amounts of setting agent and curing agent to take up any free water and further encapsulate the hardened material within the container. 30 claims

  3. Acidifier application rate impacts on ammonia emissions from US roaster chicken houses

    Science.gov (United States)

    Shah, Sanjay B.; Grimes, Jesse L.; Oviedo-Rondón, Edgar O.; Westerman, Philip W.

    2014-08-01

    Due to its potential environmental and public health impacts, emissions of ammonia (NH3) as well as several other gases from US livestock farms may be regulated. Broiler houses are important sources of NH3 emissions. However, there are no emissions data from roaster (8-12 wk old broilers, ˜4 kg ea.) houses. Producers treat the litter in broiler houses with acidifiers, such as sodium bisulfate (SBS, NaHSO4) to reduce ammonia production and protect bird health. However, there is very little data on the effect of acidifiers, particularly at high application rates on ammonia emissions. The impact of different SBS application rates [High (0.95-1.46 kg m-2, whole house), Medium (0.73 kg m-2, whole house), Low (0.37-0.49 kg m-2, whole house), and Control (0.37-0.49 kg m-2, brood chamber)] on ammonia emissions was evaluated in commercial roaster houses over 22 months spanning eight flocks. Ammonia emission from each fan was measured with an acid scrubber that operated only when the fan operated. Emissions were calculated using >95% measured data with the rest being estimated using robust methods. Exhaust ammonia-N concentrations were inversely correlated with the SBS application rates. Emission rates on animal unit (AU, where 1 AU = 500 kg live-mass) basis (ER, g d-1 AU-1) were reduced by 27, 13, and 5%, respectively, in the High, Medium, and Low treatments vs. the Control treatment (mean: 100 g d-1 AU-1, range: 86-114 g d-1 AU-1). Emission rates for the Control treatment measured in this study on roasters were mostly higher than ERs in the literature. Differences in ERs are not only due to diet, environmental and management conditions, but also due to measurement methods.

  4. Long-term trends in visibility and at Chengdu, China.

    Directory of Open Access Journals (Sweden)

    Qiyuan Wang

    Full Text Available Long-term (1973 to 2010 trends in visibility at Chengdu, China were investigated using meteorological data from the U.S. National Climatic Data Center. The visual range exhibited a declining trend before 1982, a slight increase between 1983 and 1995, a sharp decrease between 1996 and 2005, and some improvements after 2006. The trends in visibility were generally consistent with the economic development and implementation of pollution controls in China. Intensive PM2.5 measurements were conducted from 2009 to 2010 to determine the causes of visibility degradation. An analysis based on a modification of the IMPROVE approach indicated that PM2.5 ammonium bisulfate contributed 27.7% to the light extinction coefficient (bext ; this was followed by organic mass (21.7%, moisture (20.6%, and ammonium nitrate (16.3%. Contributions from elemental carbon (9.4% and soil dust (4.3% were relatively minor. Anthropogenic aerosol components (sulfate, nitrate, and elemental carbon and moisture at the surface also were important determinants of the aerosol optical depth (AOD at 550 nm, and the spatial distributions of both bext and AOD were strongly affected by regional topography. A Positive Matrix Factorization receptor model suggested that coal combustion was the largest contributor to PM2.5 mass (42.3% and the dry-air light-scattering coefficient (47.7%; this was followed by vehicular emissions (23.4% and 20.5%, respectively, industrial emissions (14.9% and 18.8%, biomass burning (12.8% and 11.9%, and fugitive dust (6.6% and 1.1%. Our observations provide a scientific basis for improving visibility in this area.

  5. Aged organic aerosol in the Eastern Mediterranean: the Finokalia Aerosol Measurement Experiment – 2008

    Directory of Open Access Journals (Sweden)

    L. Hildebrandt

    2010-05-01

    Full Text Available Aged organic aerosol (OA was measured at a remote coastal site on the island of Crete, Greece during the Finokalia Aerosol Measurement Experiment-2008 (FAME-2008, which was part of the EUCAARI intensive campaign of May 2008. The site at Finokalia is influenced by air masses from different source regions, including long-range transport of pollution from continental Europe. A quadrupole aerosol mass spectrometer (Q-AMS was employed to measure the size-resolved chemical composition of non-refractory submicron aerosol (NR-PM1, and to estimate the extent of oxidation of the organic aerosol. Factor analysis was used to gain insights into the processes and sources affecting the OA composition. The particles were internally mixed and liquid. The largest fraction of the dry NR-PM1 sampled was ammonium sulfate and ammonium bisulfate, followed by organics and a small amount of nitrate. The variability in OA composition could be explained with two factors of oxygenated organic aerosol (OOA with differing extents of oxidation but similar volatility. Hydrocarbon-like organic aerosol (HOA was not detected. There was no statistically significant diurnal variation in the bulk composition of NR-PM1 such as total sulfate or total organic aerosol concentrations. However, the OA composition exhibited statistically significant diurnal variation with more oxidized OA in the afternoon. The organic aerosol was highly oxidized, regardless of the source region. Total OA concentrations also varied little with source region, suggesting that local sources had only a small effect on OA concentrations measured at Finokalia. The aerosol was transported for about one day before arriving at the site, corresponding to an OH exposure of approximately 4×1011 molecules cm−3 s. The constant extent of oxidation suggests that atmospheric aging results in a highly oxidized OA at these OH exposures, regardless of the aerosol source.

  6. MBRidge: an accurate and cost-effective method for profiling DNA methylome at single-base resolution.

    Science.gov (United States)

    Cai, Wanshi; Mao, Fengbiao; Teng, Huajing; Cai, Tao; Zhao, Fangqing; Wu, Jinyu; Sun, Zhong Sheng

    2015-08-01

    Organisms and cells, in response to environmental influences or during development, undergo considerable changes in DNA methylation on a genome-wide scale, which are linked to a variety of biological processes. Using MethylC-seq to decipher DNA methylome at single-base resolution is prohibitively costly. In this study, we develop a novel approach, named MBRidge, to detect the methylation levels of repertoire CpGs, by innovatively introducing C-hydroxylmethylated adapters and bisulfate treatment into the MeDIP-seq protocol and employing ridge regression in data analysis. A systematic evaluation of DNA methylome in a human ovarian cell line T29 showed that MBRidge achieved high correlation (R > 0.90) with much less cost (∼10%) in comparison with MethylC-seq. We further applied MBRidge to profiling DNA methylome in T29H, an oncogenic counterpart of T29's. By comparing methylomes of T29H and T29, we identified 131790 differential methylation regions (DMRs), which are mainly enriched in carcinogenesis-related pathways. These are substantially different from 7567 DMRs that were obtained by RRBS and related with cell development or differentiation. The integrated analysis of DMRs in the promoter and expression of DMR-corresponding genes revealed that DNA methylation enforced reverse regulation of gene expression, depending on the distance from the proximal DMR to transcription starting sites in both mRNA and lncRNA. Taken together, our results demonstrate that MBRidge is an efficient and cost-effective method that can be widely applied to profiling DNA methylomes. PMID:26078362

  7. 固体酸催化蓖麻油制备生物柴油%Preparation of biodiesel from castor seed oil using solid acid as a catalyst

    Institute of Scientific and Technical Information of China (English)

    靳福全; 牛宇岚; 李晓红

    2011-01-01

    以一水硫酸氢钠固体酸为催化剂,对蓖麻油酯交换制备生物柴油进行了研究.在反应温度为75℃条件下,考察了醇油摩尔比、催化剂用量(占油质量)及反应时间对酯交换反应的影响.在反应温度为75℃、醇油摩尔比为9:1、催化剂用量为4%、反应时间为8 h的优化工艺条件下,平均甘油收率达93%,产物中甲酯总含量为95.20%.甲酯和甘油静置分层快,后处理简单,对环境无污染.%The transesterification of castor seed oil to produce biodiesel catalyzed by solid acid sodium bisulfate monohydrate was studied. At the temperature of 75 ℃, effects of molar ratio of methanol to oil, catalyst dosage ( mass ratio of catalyst to oil) and reaction time on the transesterification were investigated. Under the optimal conditions of reaction temperature 75 ℃, molar ratio of methanol to oil 9: 1, catalyst dosage 4% and reaction time 8 h, the average yield of glycerine arrived 93% . The products were analyzed by GC - MS and the mass fraction of methyl ester was 95.20%. The methyl ester and the glycerine were easily separated, and the method had no pollution to the environment.

  8. Synthesis, crystal structure and characterization of Na3H(SO4)1.78(SeO4)0.22

    Science.gov (United States)

    Ben Hassen, C.; Boujelbene, M.; Mhiri, T.

    2013-05-01

    Synthesis, crystal structure, Raman, IR and TG/DTA characterization are given for Trisodium hydrogen bisulfate selenite Na3H(SO4)1.78(SeO4)0.22. This compound crystallizes in the monoclinic system with space group P21/c and cell parameters: a = 8.6787 (4) Å, b = 9.6631 (6) Å, c = 9.2070 (5) Å, ß = 108.825 (4)°, Z = 4 and V = 730.83 (7) Å3. The refinement of 2492 observed reflections (I > 2σ(I)) leads to R1 = 0.045 and wR2 = 0.125. The structure is characterized by S/SeO4 tetrahedra which are linked into isolated pairs by hydrogen bonds which form dimers of composition [H(SO)2]. The existence of O-H and (S/Se)-O bonds in the structure at room temperature has been confirmed by IR and Raman spectroscopy in the frequency ranges 50-1300 and 500-4000 cm-1, respectively. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) measurements have been carried out on Na3H(SO4)1.78(SeO4)0.22 crystal in the temperature range between 50 and 600 °C. Water evolution and major thermal decomposition take place with onset temperatures of approximately 282 °C and 395 °C, respectively. A Raman study of the decomposition of Na3H(SO4)1.78(SeO4)0.22 as a function of temperature supports a reaction sequence and possible intermediates during the process.

  9. Hypermethylations of RASAL1 and KLOTHO is associated with renal dysfunction in a Chinese population environmentally exposed to cadmium

    International Nuclear Information System (INIS)

    Exposure to cadmium (Cd) can affect both DNA methylation and renal function, but there are few examples of the association between epigenetic markers and Cd-induced kidney damage. It has been suggested that hypermethylation of the genes RASAL1 and KLOTHO is associated with renal fibrogenesis. To investigate whether hypermethylation of RASAL1 and KLOTHO in peripheral blood DNA can be associated with Cd exposure and/or Cd-induced renal dysfunction, the degrees of methylation of RASAL1 and KLOTHO in peripheral blood DNA from 81 residents in Cd-polluted and non-polluted areas were measured using bisulfate-PCR-pyrosequencing. Changes in blood cadmium (BCd), urinary cadmium (UCd), and kidney parameters were measured, and the glomerular filtration rate (eGFR) was estimated. The levels of BCd and UCd correlated positively with the levels of DNA methylation in RASAL1 and in KLOTHO. The more heavily exposed residents (BCd, 4.23–13.22 μg/L; UCd, 8.65–32.90 μg/g creatinine) exhibited obvious renal dysfunction. Notably, when Cd concentration in blood and urine was adjusted, the increased methylation level in RASAL1 was inversely correlated with eGFR (P < 0.01) but the relationship between hypermethylation of KLOTHO and eGFR was not statistically significant. The methylation of RASAL1 increased along with the increased abnormal prevalence of eGFR. Our findings suggest that Cd exposure can induce the hypermethylation of RASAL1 and KLOTHO. Hypermethylation of RASAL1 may be an indicator of the progress for chronic kidney disease. - Highlights: • A long term heavily Cd exposure induced renal dysfunction. • Cd exposure correlated positively with DNA methylation in RASAL1 and KLOTHO. • Hypermethylation of RASAL1 correlated with adjusted renal function indicators

  10. Hypermethylations of RASAL1 and KLOTHO is associated with renal dysfunction in a Chinese population environmentally exposed to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chen; Liang, Yihuai [School of Public Health, Fudan University, 130 DongAn Road, Shanghai 200032 (China); Key Laboratory of Public Health Safety, Ministry of Education, 130 DongAn Road, Shanghai 200032 (China); Lei, Lijian [Department of Epidemiology, School of Public Health, Shanxi Medical University, Shanxi (China); Zhu, Guoying; Chen, Xiao [Department of Bone Metabolism, Institute of Radiation Medicine, Fudan University, Shanghai (China); Jin, Taiyi, E-mail: tyjin@shmu.edu.cn [School of Public Health, Fudan University, 130 DongAn Road, Shanghai 200032 (China); Key Laboratory of Public Health Safety, Ministry of Education, 130 DongAn Road, Shanghai 200032 (China); Wu, Qing, E-mail: qingwu@fudan.edu.cn [School of Public Health, Fudan University, 130 DongAn Road, Shanghai 200032 (China); Key Laboratory of Public Health Safety, Ministry of Education, 130 DongAn Road, Shanghai 200032 (China)

    2013-08-15

    Exposure to cadmium (Cd) can affect both DNA methylation and renal function, but there are few examples of the association between epigenetic markers and Cd-induced kidney damage. It has been suggested that hypermethylation of the genes RASAL1 and KLOTHO is associated with renal fibrogenesis. To investigate whether hypermethylation of RASAL1 and KLOTHO in peripheral blood DNA can be associated with Cd exposure and/or Cd-induced renal dysfunction, the degrees of methylation of RASAL1 and KLOTHO in peripheral blood DNA from 81 residents in Cd-polluted and non-polluted areas were measured using bisulfate-PCR-pyrosequencing. Changes in blood cadmium (BCd), urinary cadmium (UCd), and kidney parameters were measured, and the glomerular filtration rate (eGFR) was estimated. The levels of BCd and UCd correlated positively with the levels of DNA methylation in RASAL1 and in KLOTHO. The more heavily exposed residents (BCd, 4.23–13.22 μg/L; UCd, 8.65–32.90 μg/g creatinine) exhibited obvious renal dysfunction. Notably, when Cd concentration in blood and urine was adjusted, the increased methylation level in RASAL1 was inversely correlated with eGFR (P < 0.01) but the relationship between hypermethylation of KLOTHO and eGFR was not statistically significant. The methylation of RASAL1 increased along with the increased abnormal prevalence of eGFR. Our findings suggest that Cd exposure can induce the hypermethylation of RASAL1 and KLOTHO. Hypermethylation of RASAL1 may be an indicator of the progress for chronic kidney disease. - Highlights: • A long term heavily Cd exposure induced renal dysfunction. • Cd exposure correlated positively with DNA methylation in RASAL1 and KLOTHO. • Hypermethylation of RASAL1 correlated with adjusted renal function indicators.

  11. Microwave-assisted Heating Synthesis of Vanillin Propylene Glycol Acetal Catalyzed by NaHSO4%微波促进硫酸氢钠催化合成香兰素1.2-丙二醇缩醛

    Institute of Scientific and Technical Information of China (English)

    吴文陵; 林明穗; 王仁章; 吴泽民; 叶欣

    2012-01-01

    在微波辐射条件下,香兰索与1.2-丙二醇在硫酸氢钠的催化下.合成了香兰索丙二醇缩醛。探讨了原料配比、催化剂用量、微波辐射功率及时问等因素对反应的影响。适宜反应条件为:n(1,2-丙二醇):n(香兰素)=2.2,20ml环已烷作带水剂,3.0g/mol硫酸氢钠作催化剂,辐射功率500w,辐射时间10min,香兰素转化率可达68.2%。结果表明,微波辐射与催化荆联用,可大大缩短反应时间,反应过程环保简便。%The vanillin 1, 2 - propylene glycol acetal was synthesized by the reaction of vanillin and 1, 2-propylene glycol using sodium bisulfate as catalyst under microwave irradiation. Factors influencing the reaction, such as different mole ratio of materials, catalyst amounts, microwave irradiation power and time, were discussed. The optimal synthetic technology was obtained as follows: n (1, 2 - propylene glycol) : n (vanillin) = 2.2, irradiation power 500 W, irradiation time 10 rain, NariS04 3.0 g/mol ( based on the amount of vanillin), 20ml cyclohexane to give in 68.2% yield.

  12. Modeling impacts of NH3 on uptake of H2SO4 by charged nucleating nanoparticles in the Earth's atmosphere

    Science.gov (United States)

    Nadykto, A. B.; Nazarenko, K. M.; Markov, P. N.; Yu, F.

    2016-06-01

    The understanding of the role of ammonia, a well-known stabilizer of binary sulfuric acid-water clusters, in the gas-to-nanoparticle conversion in the Earth atmosphere is critically important for the assessment of aerosol radiative forcing associated with the climate changes. The sulfuric acid H2SO4 is present in the atmosphere in the form of the gas-phase hydrates (H2SO4)(H2O)n, whose interaction with NH3 leads to the formation of more stable bisulfate clusters (NH3)(H2SO4)(H2O)n. Although the impact of NH3 on the thermochemical stability of binary clusters nucleating homogeneously has been studied in some detail in the past, the effect of ammonia on other microphysical properties relevant to nucleation remains insufficiently well understood. In the present study, the effect of ammonia on the electrical dipole moment controlling the nucleation of airborne ions via the dipole-charge interaction has been investigated using the Density Functional Theory (DFT), ab initio MP2 and model chemistry G3 methods. The presence of ammonia in (H2SO4)(H2O)n is found to lead to very large enhancement in the dipole moment, which exceeds 2.0-2.5 Debyes (˜60-80%), 3.7-5.0 Debyes (˜90-180%), 1.4-4.5 Debyes (˜50-150%) and 2.1-5.5 Debyes (˜60-700%) for n = 0, n = 1, n = 2 and n = 3, respectively. The implications of this include the significantly increased uptake of the sulfuric acid, the key atmospheric nucleation precursor, by airborne ions and neutrals (due to dipole-dipole interaction), enhanced nucleation rates and the elevated production of ultrafine particles, which cause adverse health impacts.

  13. Aged organic aerosol in the Eastern Mediterranean: the Finokalia Aerosol Measurement Experiment - 2008

    Science.gov (United States)

    Hildebrandt, L.; Engelhart, G. J.; Mohr, C.; Kostenidou, E.; Lanz, V. A.; Bougiatioti, A.; Decarlo, P. F.; Prevot, A. S. H.; Baltensperger, U.; Mihalopoulos, N.; Donahue, N. M.; Pandis, S. N.

    2010-05-01

    Aged organic aerosol (OA) was measured at a remote coastal site on the island of Crete, Greece during the Finokalia Aerosol Measurement Experiment-2008 (FAME-2008), which was part of the EUCAARI intensive campaign of May 2008. The site at Finokalia is influenced by air masses from different source regions, including long-range transport of pollution from continental Europe. A quadrupole aerosol mass spectrometer (Q-AMS) was employed to measure the size-resolved chemical composition of non-refractory submicron aerosol (NR-PM1), and to estimate the extent of oxidation of the organic aerosol. Factor analysis was used to gain insights into the processes and sources affecting the OA composition. The particles were internally mixed and liquid. The largest fraction of the dry NR-PM1 sampled was ammonium sulfate and ammonium bisulfate, followed by organics and a small amount of nitrate. The variability in OA composition could be explained with two factors of oxygenated organic aerosol (OOA) with differing extents of oxidation but similar volatility. Hydrocarbon-like organic aerosol (HOA) was not detected. There was no statistically significant diurnal variation in the bulk composition of NR-PM1 such as total sulfate or total organic aerosol concentrations. However, the OA composition exhibited statistically significant diurnal variation with more oxidized OA in the afternoon. The organic aerosol was highly oxidized, regardless of the source region. Total OA concentrations also varied little with source region, suggesting that local sources had only a small effect on OA concentrations measured at Finokalia. The aerosol was transported for about one day before arriving at the site, corresponding to an OH exposure of approximately 4×1011 molecules cm-3 s. The constant extent of oxidation suggests that atmospheric aging results in a highly oxidized OA at these OH exposures, regardless of the aerosol source.

  14. Altered DNA methylation patterns of the H19 differentially methylated region and the DAZL gene promoter are associated with defective human sperm.

    Directory of Open Access Journals (Sweden)

    Bo Li

    Full Text Available DNA methylation disturbance is associated with defective human sperm. However, oligozoospermia (OZ and asthenozoospermia (AZ usually present together, and the relationship between the single-phenotype defects in human sperm and DNA methylation is poorly understood. In this study, 20 infertile OZ patients and 20 infertile AZ patients were compared with 20 fertile normozoospermic men. Bisulfate-specific PCR was used to analyze DNA methylation of the H19-DMR and the DAZL promoter in these subjects. A similar DNA methylation pattern of the H19-DMR was detected in AZ and NZ(control, with only complete methylation and mild hypomethylation(0.05. However, the methylation pattern of severe hypomethylation (>50% unmethylated CpGs and complete unmethylation was only detected in 5 OZ patients, and the occurrence of these two methylation patterns was 8.54±10.86% and 9±6.06%, respectively. Loss of DNA methylation of the H19-DMR in the OZ patients was found to mainly occur in CTCF-binding site 6, with occurrence of 18.15±14.71%, which was much higher than that in patients with NZ (0.84±2.05% and AZ (0.58±1.77% (P20% methylated clones in the DAZL promoter only in infertile patients, there was no significant difference between the AZ and OZ patients in the proportion of moderately-to-severely hypermethylated clones (p>0.05. In all cases, global sperm genome methylation analyses, using LINE1 transposon as the indicator, showed that dysregulation of DNA methylation is specifically associated with the H19-DMR and DAZL promoter. Therefore, abnormal DNA methylation status of H19-DMR, especially at the CTCF-binding site 6, is closely associated with OZ. Abnormal DNA methylation of the DAZL promoter might represent an epigenetic marker of male infertility.

  15. Possible involvement of locus-specific methylation on expression regulation of leafy homologous gene (CiLFY during precocious trifoliate orange phase change process.

    Directory of Open Access Journals (Sweden)

    Jin-Zhi Zhang

    Full Text Available DNA methylation plays an essential role in regulating plant development. Here, we described an early flowering trifoliate orange (precocious trifoliate orange, Poncirus trifoliata L. Raf was treated with 5-azacytidine and displayed a number of phenotypic and developmental abnormalities. These observations suggested that DNA methylation might play an important role in regulating many developmental pathways including early flowering trait, and then the expression level of five key or integrated citrus flowering genes were analyzed. Our results showed that flowering locus T (CiFT relative expression level was increased with the increasing concentrations of 5-AzaC. However, leafy (CiLFY, APETELA1 (CiAP1, terminal flower1 (CiTFL1, and flowering locus C (CiFLC showed highest relative expression levels at 250 µΜ treatment, while decreased sharply at higher concentrations. In order to further confirm DNA methylation affects the expression of these genes, their full-length sequences were isolated by genome-walker method, and then was analyzed by using bioinformatics tools. However, only one locus-specific methylation site was observed in CiLFY sequence. Therefore, DNA methylation level of the CiLFY was investigated both at juvenile and adult stages of precocious trifoliate orange by bisulfate sequencing PCR; it has been shown that the level of DNA methylation was altered during phase change. In addition, spatial and temporal expression patterns of CiLFY promoter and a series of 5' deletions were investigated by driving the expression of a β-glucuronidase reporter gene in Arabidopsis. Exogenous GA3 treatment on transgenic Arabidopsis revealed that GA3 might be involved in the developmental regulation of CiLFY during flowering process of precocious trifoliate orange. These results provided insights into the molecular regulation of CiLFY gene expression, which would be helpful for studying citrus flowering.

  16. P2Y12 Receptor Localizes in the Renal Collecting Duct and Its Blockade Augments Arginine Vasopressin Action and Alleviates Nephrogenic Diabetes Insipidus.

    Science.gov (United States)

    Zhang, Yue; Peti-Peterdi, Janos; Müller, Christa E; Carlson, Noel G; Baqi, Younis; Strasburg, David L; Heiney, Kristina M; Villanueva, Karie; Kohan, Donald E; Kishore, Bellamkonda K

    2015-12-01

    P2Y12 receptor (P2Y12-R) signaling is mediated through Gi, ultimately reducing cellular cAMP levels. Because cAMP is a central modulator of arginine vasopressin (AVP)-induced water transport in the renal collecting duct (CD), we hypothesized that if expressed in the CD, P2Y12-R may play a role in renal handling of water in health and in nephrogenic diabetes insipidus. We found P2Y12-R mRNA expression in rat kidney, and immunolocalized its protein and aquaporin-2 (AQP2) in CD principal cells. Administration of clopidogrel bisulfate, an irreversible inhibitor of P2Y12-R, significantly increased urine concentration and AQP2 protein in the kidneys of Sprague-Dawley rats. Notably, clopidogrel did not alter urine concentration in Brattleboro rats that lack AVP. Clopidogrel administration also significantly ameliorated lithium-induced polyuria, improved urine concentrating ability and AQP2 protein abundance, and reversed the lithium-induced increase in free-water excretion, without decreasing blood or kidney tissue lithium levels. Clopidogrel administration also augmented the lithium-induced increase in urinary AVP excretion and suppressed the lithium-induced increase in urinary nitrates/nitrites (nitric oxide production) and 8-isoprostane (oxidative stress). Furthermore, selective blockade of P2Y12-R by the reversible antagonist PSB-0739 in primary cultures of rat inner medullary CD cells potentiated the expression of AQP2 and AQP3 mRNA, and cAMP production induced by dDAVP (desmopressin). In conclusion, pharmacologic blockade of renal P2Y12-R increases urinary concentrating ability by augmenting the effect of AVP on the kidney and ameliorates lithium-induced NDI by potentiating the action of AVP on the CD. This strategy may offer a novel and effective therapy for lithium-induced NDI. PMID:25855780

  17. HYBRID SELECTIVE NON-CATALYTIC REDUCTION (SNCR)/SELECTIVE CATALYTIC REDUCTION (SCR) DEMONSTRATION FOR THE REMOVAL OF NOx FROM BOILER FLUE GASES

    Energy Technology Data Exchange (ETDEWEB)

    Jerry B. Urbas

    1999-05-01

    The U. S. Department of Energy (DOE), Electric Power Research Institute (EPRI), Pennsylvania Electric Energy Research Council, (PEERC), New York State Electric and Gas and GPU Generation, Inc. jointly funded a demonstration to determine the capabilities for Hybrid SNCR/SCR (Selective Non-Catalytic Reduction/Selective Catalytic Reduction) technology. The demonstration site was GPU Generation's Seward Unit No.5 (147MW) located in Seward Pennsylvania. The demonstration began in October of 1997 and ended in December 1998. DOE funding was provided through Grant No. DE-FG22-96PC96256 with T. J. Feeley as the Project Manager. EPRI funding was provided through agreements TC4599-001-26999 and TC4599-002-26999 with E. Hughes as the Project Manager. This project demonstrated the operation of the Hybrid SNCR/SCR NO{sub x} control process on a full-scale coal fired utility boiler. The hybrid technology was expected to provide a cost-effective method of reducing NO{sub x} while balancing capital and operation costs. An existing urea based SNCR system was modified with an expanded-duct catalyst to provide increased NO{sub x} reduction efficiency from the SNCR while producing increased ammonia slip levels to the catalyst. The catalyst was sized to reduce the ammonia slip to the air heaters to less than 2 ppm while providing equivalent NO{sub x} reductions. The project goals were to demonstrate hybrid technology is capable of achieving at least a 55% reduction in NO{sub x} emissions while maintaining less than 2ppm ammonia slip to the air heaters, maintain flyash marketability, verify the cost benefit and applicability of Hybrid post combustion technology, and reduce forced outages due to ammonium bisulfate (ABS) fouling of the air heaters. Early system limitations, due to gas temperature stratification, restricted the Hybrid NO{sub x} reduction capabilities to 48% with an ammonia slip of 6.1 mg/Nm{sup 3} (8 ppm) at the catalyst inlet. After resolving the stratification

  18. HYBRID SELECTIVE NON-CATALYTIC REDUCTION (SNCR)/SELECTIVE CATALYTIC REDUCTION (SCR) DEMONSTRATION FOR THE REMOVAL OF NOx FROM BOILER FLUE GASES; FINAL

    International Nuclear Information System (INIS)

    The U. S. Department of Energy (DOE), Electric Power Research Institute (EPRI), Pennsylvania Electric Energy Research Council, (PEERC), New York State Electric and Gas and GPU Generation, Inc. jointly funded a demonstration to determine the capabilities for Hybrid SNCR/SCR (Selective Non-Catalytic Reduction/Selective Catalytic Reduction) technology. The demonstration site was GPU Generation's Seward Unit No.5 (147MW) located in Seward Pennsylvania. The demonstration began in October of 1997 and ended in December 1998. DOE funding was provided through Grant No. DE-FG22-96PC96256 with T. J. Feeley as the Project Manager. EPRI funding was provided through agreements TC4599-001-26999 and TC4599-002-26999 with E. Hughes as the Project Manager. This project demonstrated the operation of the Hybrid SNCR/SCR NO(sub x) control process on a full-scale coal fired utility boiler. The hybrid technology was expected to provide a cost-effective method of reducing NO(sub x) while balancing capital and operation costs. An existing urea based SNCR system was modified with an expanded-duct catalyst to provide increased NO(sub x) reduction efficiency from the SNCR while producing increased ammonia slip levels to the catalyst. The catalyst was sized to reduce the ammonia slip to the air heaters to less than 2 ppm while providing equivalent NO(sub x) reductions. The project goals were to demonstrate hybrid technology is capable of achieving at least a 55% reduction in NO(sub x) emissions while maintaining less than 2ppm ammonia slip to the air heaters, maintain flyash marketability, verify the cost benefit and applicability of Hybrid post combustion technology, and reduce forced outages due to ammonium bisulfate (ABS) fouling of the air heaters. Early system limitations, due to gas temperature stratification, restricted the Hybrid NO(sub x) reduction capabilities to 48% with an ammonia slip of 6.1 mg/Nm(sup 3) (8 ppm) at the catalyst inlet. After resolving the stratification problem

  19. Intumescent Coatings as Fire Retardants

    Science.gov (United States)

    Parker, J. A.; Fohlen, G. M.; Sawko, P. M.; Fish, R. H.

    1970-01-01

    The development of fire-retardant coatings to protect surfaces which may be exposed to fire or extreme heat is a subject of intense interest to many industries. A fire-retardant paint has been developed which represents a new chemical approach for preparing intumescent coatings, and potentially, is very important to fire-prevention authorities. The requirements for a superior coating include ease of application, suitability to a wide variety of surfaces and finishes, and stability over an extended period of time within a broad range of ambient temperature and humidity conditions. These innovative coatings, when activated by the heat of a fire, react to form a thick, low-density, polymeric coating or char layer. Water vapor and sulphur dioxide are released during the intumescent reaction. Two fire-protection mechanisms thus become available: (1) the char layer retards the flow of heat, due to the extremely low thermal conductivity; and (2) water vapor and sulfur dioxide are released, providing fire quenching properties. Still another mechanism functions in cases where the char, by virtue of its high oxidation resistance and low thermal conductivity, reaches a sufficiently high temperature to re-radiate much of the incident heat load. The coatings consist of dispersions of selective salts of a nitro-amino-arornatic compound. Specifically, para-nitroaniline bisulfate and the ammonium salt of para-nitroaniline-ortho sulphuric acid (2-amino-5-nitrobenzenesulphuric acid) are used. Suitable vehicles are cellulose nitrate of lacquer grade, a nitrite-phenolic modified rubber, or epoxy-polysulfide copolymer. Three separate formulations have been developed. A solvent is usually employed, such as methylethyl ketone, butyl acetate, or toluene, which renders the coatings suitably thin and which evaporates after the coatings are applied. Generally, the intumescent material is treated as insoluble in the vehicle, and is ground and dispersed in the vehicle and solvent like an

  20. Epigenetic silencing of MAL, a putative tumor suppressor gene, can contribute to human epithelium cell carcinoma

    Directory of Open Access Journals (Sweden)

    Zhang Jun

    2010-11-01

    Full Text Available Abstract Background To identify new and useful candidate biomarkers in head and neck squamous cell carcinoma (HNSCC, we performed a genome-wide survey and found that Myelin and lymphocyte-associated protein (MAL was a gene that was markedly down-regulated in HNSCC. Hence, we investigated the mechanism of MAL silencing and the effects of MAL on the proliferation, invasion, and apoptotic potential in HNSCC. Results MAL was significantly down-regulated in 91.7% of HNSCC specimens at the mRNA level as compared with adjacent normal tissues (P = 0.0004. Moreover, the relative transcript levels of the MAL gene were remarkably decreased by five-fold in nine HNSCC cell lines as compared with normal head and neck epithelium cells. MAL gene expression was restored in 44%, 67%, and 89% in HNSCC cell lines treated with TSA, 5-Aza-dC, and TSA plus 5-Aza-dC, respectively. Furthermore, bisulfate-treated DNA sequencing demonstrated that the two CpG islands (that is, M1 and M2 located in MAL promoter region were completely methylated in the HNSCC cell lines (CpG methylated ratio was more than 90%, and only one CpG island (that is, M1 was partially methylated in HNSCC tissues (CpG methylated ratio between 20% and 90%. A significant reduction in cell proliferation and a change in the cell cycle profile were also observed in MAL transfectants. Matrigel assay demonstrated that the invasiveness of HNSCC cells significantly decreased. A significant increase in the population of apoptotic cells was observed in MAL transfected cells. The exogenous expression of the MAL gene suppressed malignant phenotypes, while the cell death induced by MAL gene transfer was a result of apoptosis as demonstrated by the induction of cleavage of the poly (that is, ADP-ribose polymerase. Additionally, tumor growth was suppressed in cells expressing MAL as compared with cells not expressing MAL. Conclusion Our data suggest that the epigenetic inactivation of MAL, as a candidate tumor

  1. Medición de la exposición al humo ambiental de tabaco en centros de enseñanza, centros sanitarios, medios de transporte y lugares de ocio Measurement of exposure to environmental tobacco smoke in education centers, health centers, transport facilities and leisure places

    Directory of Open Access Journals (Sweden)

    María J. López

    2004-12-01

    Full Text Available Objetivos: Describir los niveles de exposición al humo ambiental de tabaco (HAT a los que está expuesta la población en diferentes espacios públicos en Barcelona. Material y método: La nicotina en fase vapor se midió mediante monitores pasivos que contenían un filtro de 37 mm de diámetro tratado con bisulfato sódico en su interior. Se tomaron muestras en colegios de primaria y secundaria, hospitales, centros de atención primaria, estaciones de tren, transportes metropolitanos, universidades, aeropuerto, restaurantes y discotecas. Resultados: Los centros de enseñanza (primaria y secundaria y los centros sanitarios presentan los niveles de exposición al HAT más bajos y en todos ellos la concentración media es Objectives: To describe levels of exposure to environmental tobacco smoke (ETS in various public places in Barcelona (Spain. Material and method: Vapor-phase nicotine was measured with passive samplers containing a sodium bisulfate treated filter with a 37 mm diameter. The places sampled were primary and secondary schools, hospitals, primary care centers, train stations, subways, universities, airports, restaurants and discotheques. Results: Primary and secondary schools and health centers had the lowest levels of ETS exposure, with mean concentrations of less than 1 μg/m3. The mean values found in transport and universities were 2.16 μg/m3 in train stations, 3.30 μg/m3 in subways, 4.30 μg/m3 in airports and 4.97 μg/m3 in universities. The highest concentrations were found in restaurants and discotheques, with mean values of 12.36 μg/m3 in restaurants and 130.65 μg/m3 in discotheques. All samples taken from primary and secondary schools, airports, subways, restaurants and discotheques contained ETS. Likewise, 90% of the samples taken from train stations and 96% of those from universities contained ETS. Seventy-nine percent of the samples from hospitals and 58% of those from primary care centers contained ETS. Conclusions

  2. 酸性功能化双核离子液体催化合成酯的研究%Study of Catalyzed Synthesis of Ester by Acid Functionalized Dacational Ionic Liqiud

    Institute of Scientific and Technical Information of China (English)

    石月丹; 刘春光; 王楠; 徐凛然; 梅楚鹤; 郭珊珊

    2014-01-01

    In this issue,bis-(3-methyl-1-imidazole)butylidene double bisulfate(MTEIMHS) was used as a catalyst to synthetize isoamyl isobutyrate and Isoamyl butyrate. The yield of esterification rate under the influ-ence of the reaction conditions was measured. The results showed that under the optimized conditions of isoamyl isobutyrate :n(isoamylol) ∶ n(isobutyric acid)=1. 2 ∶ 1,catalyst used dosage 2. 0g and 3. 5h,the yield of isoamyl isobutyrate reached 95 . 4%. The results showed that under the optimized conditions of Isoamyl buty-rate:n(isoamylol) ∶ n(butyric acid)=1. 6 ∶ 1,catalyst used dosage 2. 0g and 3h,the yield of isoamyl isobu-tyrate reached 97 . 9%. The reaction mixture was immiscible with MTEIMHS and could be speparated simply by separatory funnel after reaction. The ionic liquid catalyst could be reused for 6 times without noticeable lowering of activity.%以自制的双-(3-甲基-1-咪唑)亚丁基二硫酸氢盐离子液体为催化合成了异丁酸异戊酯和丁酸异戊酯,考察了反应条件对酯化率的影响。结果表明,异丁酸异戊酯最佳的合成条件为:醇酸摩尔量比1.2∶1,催化剂用量为2.0 g,反应时间3.5 h,酯化率达到95.4%。丁酸异戊酯最佳的合成条件为:醇酸摩尔量比1.6∶1,催化剂用量为2.0 g,反应时间3.5 h,酯化率达到97.9%。反应结束后反应混合物与催化剂自动分层,采用分液的方式即可分离出催化剂,简化了分离过程。离子液体重复使用6次,催化效果无明显降低。

  3. Synthesis of Foliar Fertilizer from Titanium-Bearing Blast Furnace Slag and Cultivation Experiment of Sweet Corn%由含钛高炉渣制备叶面肥及甜玉米栽培实验研究

    Institute of Scientific and Technical Information of China (English)

    张悦; 薛向欣

    2016-01-01

    The foliar fertilizer was synthesized with the titanium-bearing blast furnace slag, potassium bisulfate,citric acid,urea and magnesium oxide as raw materials by melting and chelating methods.The field cultivation experiments of sweet corns were carried out in order to evaluate the effects of the foliar fertilizer on the growth,yield,characters and the SPAD value of nitrogen,magnesium,sugar and heavy metal in grains.The results showed that the foliar fertilizer contained nutritional elements such as nitrogen, sulfur, potassium, iron, titanium and magnesium.The application of the foliar fertilizer shortened the growing period of the sweet corn by 2 days,and also made the yield,plant heights,diameters of the stem and ears,grain number per panicle,weight of single spike,and the number of efficient panicles per plant,together with the SPAD value of chlorophyll in leaves,nitrogen and magnesium in grains significantly increase. However,there was no difference in the mass fraction of sugar,titanium,vanadium and chromium in the sweet corn.In addition,mass fractions of the heavy metal elements like vanadium and chromium in the sweet corn were below the maximum residue limit set by National Standards of China.%以含钛高炉渣、硫酸氢钾、柠檬酸、尿素和氧化镁为原料,采用熔融和螯合法制备叶面肥,并通过大田栽培实验研究了该叶面肥对甜玉米生长状况、产量、性状及籽粒的氮、镁、糖和重金属质量分数的影响。结果表明,该叶面肥含有植物营养元素氮、硫、钾、镁、铁和钛;该叶面肥的施用使甜玉米生育期缩短2d;产量、株高、茎粗、穗粗、穗粒数、单穗重、单株有效穗数、叶片中叶绿素的 SPAD 值、籽粒中氮和镁的质量分数明显增加,籽粒中糖、钛、钒和铬的质量分数无明显变化,且重金属元素钒和铬的质量分数符合国家标准。

  4. Sensitivity of thermal infrared nadir instruments to the chemical and microphysical properties of UTLS secondary sulfate aerosols

    Science.gov (United States)

    Sellitto, P.; Legras, B.

    2016-01-01

    Monitoring upper-tropospheric-lower-stratospheric (UTLS) secondary sulfate aerosols and their chemical and microphysical properties from satellite nadir observations is crucial to better understand their formation and evolution processes and then to estimate their impact on UTLS chemistry, and on regional and global radiative balance. Here we present a study aimed at the evaluation of the sensitivity of thermal infrared (TIR) satellite nadir observations to the chemical composition and the size distribution of idealised UTLS sulfate aerosol layers. The extinction properties of sulfuric acid/water droplets, for different sulfuric acid mixing ratios and temperatures, are systematically analysed. The extinction coefficients are derived by means of a Mie code, using refractive indices taken from the GEISA (Gestion et Étude des Informations Spectroscopiques Atmosphériques: Management and Study of Spectroscopic Information) spectroscopic database and log-normal size distributions with different effective radii and number concentrations. IASI (Infrared Atmospheric Sounding Interferometer) pseudo-observations are generated using forward radiative transfer calculations performed with the 4A (Automatized Atmospheric Absorption Atlas) radiative transfer model, to estimate the impact of the extinction of idealised aerosol layers, at typical UTLS conditions, on the brightness temperature spectra observed by this satellite instrument. We found a marked and typical spectral signature of these aerosol layers between 700 and 1200 cm-1, due to the absorption bands of the sulfate and bisulfate ions and the undissociated sulfuric acid, with the main absorption peaks at 1170 and 905 cm-1. The dependence of the aerosol spectral signature to the sulfuric acid mixing ratio, and effective number concentration and radius, as well as the role of interfering parameters like the ozone, sulfur dioxide, carbon dioxide and ash absorption, and temperature and water vapour profile uncertainties

  5. 双核离子液体的合成及其对酯化反应的催化活性%Synthesis of Binuclear Ionic Liquids and Their Catalytic Activity for Esterification

    Institute of Scientific and Technical Information of China (English)

    赵地顺; 刘猛帅; 葛京京; 张娟; 任培兵

    2012-01-01

    A series of functional binuclear ionic liquids based on bis-(3-methyl-l-imidazole)butylidene double P-toluene sul-fonic acid salt (Im-PTSA), bis-(3-methyl-l-imidazole)butylidene double bisulfate (Im-HSO4), bis-(l-pyridine)butylidene double p-toluene sulfonic acid salt (Py-PTSA), bis-(l-pyridine)butylidene double bisulfate (Py-HSO4) were synthesized by a two-step proceeding and their structures were characterized by FT-IR and 1H NMR spectra. Their thermal stabilities were characterized by TG. In addition, the acidity and solubility of functional binuclear ionic liquids were also studied. The catalytic activity of the binuclear ionic liquids for the esterification of succinic acid with ethanol was measured. The results show that under the optimized conditions of n(succinic acid) : n(ethanol)= 1 : 3, catalyst used dosage 1.90% (wt), 70 ℃ and 2.5 h, the yield of diethyl succinate reached 93.6% and the selectivity was near up to 100%. Im-PTSA was reused at least 8 times without significant decrease in activity after drying under vacuum. Austenitic stainless steel 316L was used for conducting the corrosion test under the above esterificaion condition, the corrosion rates of the steel plates dipped in the systems with these ionic liquids were less than one tenth of that with sulfuric acid. Fischer esterification of monocarboxylic acids and dicarboxylic acids with different alcohols was observed on using Im-PTSA as catalyst which gave high product yield and selectivity. Use of such a reaction catalyst should be appreciated for its convenient separation.%合成了双-(3-甲基-1-咪唑)亚丁基双对甲苯磺酸盐(Im-PTSA)、双-(3-甲基-1-咪唑)亚丁基双硫酸氢盐(Im-HSO4)、双-(1-吡啶)亚丁基双对甲苯磺酸盐(Py-PTSA)、双-(1-吡啶)亚丁基双硫酸氢盐(Py-HSO4)等4种功能化双核离子液体.分别采用红外光谱(FT-IR)、核磁共振氢谱(1H NMR)对合成的离子液体进行结构分析;采用热重(TG)测试了离子液体的热稳

  6. Soil analyses for 1,3-dichloropropene (1,3-DCP), sodium n-methyldithiocarbamate (metam-sodium), and their degradation products near Fort Hall Idaho, September 1999 through March 2000

    Science.gov (United States)

    Parliman, D.J.

    2001-01-01

    Between September 1999 and March 2000, soil samples from the Fort Hall, Idaho, area were analyzed for two soil fumigants, 1,3-dichloropropene (1,3-DCP) and sodium n-methyldithiocarbamate (metam-sodium), and their degradation products. Ground water is the only source of drinking water at Fort Hall, and the purpose of the investigation was to determine potential risk of ground-water contamination from persistence and movement of these pesticides in cropland soils. 1,3-DCP, metam-sodium, or their degradation products were detected in 42 of 104 soil samples. The samples were collected from 1-, 2-, and 3-foot depths in multiple backhoe trenches during four sampling events—before pesticide application in September; after application in October; before soil freeze in December; and after soil thaw in March. In most cases, concentrations of the pesticide compounds were at or near their laboratory minimum reporting limits. U.S. Environmental Protection Agency Method 5035 was used as the guideline for soil sample preparation and analyses, and either sodium bisulfate (NaHSO4), an acidic preservative, or pesticide-free water was added to samples prior to analyses. Addition of NaHSO4 to the samples resulted in a greater number of compound detections, but pesticide-free water was added to most samples to avoid the strong reactions of soil carbonate minerals with the NaHSO4. As a result, nondetection of compounds in samples containing pesticide-free water did not necessarily indicate that the compounds were absent. Detections of these compounds were inconsistent among trenches with similar soil characteristics and histories of soil fumigant use. Compounds were detected at different depths and different trench locations during each sampling event. Overall results of this study showed that the original compounds or their degradation products can persist in soil 6 months or more after their application and are present to at least 3 feet below land surface in some areas. A few of

  7. Sensitivity of high-spectral resolution and broadband thermal infrared nadir instruments to the chemical and microphysical properties of secondary sulfate aerosols in the upper-troposphere/lower-stratosphere

    Science.gov (United States)

    Sellitto, Pasquale; Legras, Bernard

    2016-04-01

    the brightness temperature (BT) spectra observed by satellite instruments. We isolated a marked and typical spectral signature of these aerosol layers between 700 and 1200 cm‑1, due to the absorption bands of the sulfate and bisulfate ions and the undissociated sulfuric acid, with the main absorption peaks at 1170 and 905 cm‑1 (sulfuric acid vibrational bands). The dependence of the residual aerosol spectral BT signature to the sulfuric acid mixing ratio, and effective number concentration and radius, as well as the role of interfering parameters like the ozone, sulfur dioxide, carbon dioxide and ash absorption, and temperature and water vapour profile uncertainties, are analysed and critically discussed. The information content (degrees of freedom and retrieval uncertainties) of synthetic satellite observations is estimated for different instrumental configurations. High spectral resolution (Infrared Atmospheric Sounding Interferometer (IASI)-like pseudo-observations) and broadband spectral features (Moderate Resolution Imaging Spectroradiometer (MODIS) and Spinning Enhanced Visible and InfraRed Imager (SEVIRI)-like pseudo-observations) approaches are proposed and discussed.

  8. Seasonal variations and evidence for the effectiveness of pollution controls on water-soluble inorganic species in total suspended particulates and fine particulate matter from Xi'an, China.

    Science.gov (United States)

    Shen, Zhenxing; Arimoto, Richard; Cao, Junji; Zhang, Renjian; Li, Xuxiang; Du, Na; Okuda, Tomoaki; Nakao, Shunsuke; Tanaka, Shigeru

    2008-12-01

    Total suspended particulate (TSP) and particulate matter less than 2.5 microm in aerodynamic diameter (PM2.5) samples were collected over Xi'an for a 1-yr period to characterize the seasonal variations of water-soluble inorganic ions and to evaluate the effectiveness of the pollution policies and controls during the past 10 yr. Mass concentrations of five cations (sodium [Na+], potassium [K+], ammonium [NH4+], calcium [Ca2+], and magnesium [Mg2+]) and four anions (fluoride [F-], chloride [Cl-], nitrate [NO3-], and sulfate [SO4(2-)]) were determined by ion chromatography. The yearly arithmetic-mean mass concentrations of the total measured water-soluble ions in TSP and PM2.5 were 83.9 +/- 58.4 and 45 +/- 34.3 microg x m(-3). The most abundant ions in TSP were SO4(2-), NO3-, Ca2+, and NH4+; whereas in PM2.5 the dominant ions were SO4(2-), NH4 +, and NO3-. Most of the ions were more concentrated in the PM2.5 than in TSP, but two exceptions were Ca2+ and Mg2+. Comparisons of the molar ratios of Mg2+/Ca2+ in TSP indicated that fugitive dust was the main source for these two ions, and the influence of soil dust from outside of the city was most evident during dust storms. The mass concentrations of SO4(2-), NO3-, , NH4+, and K+ in TSP were highest in winter and lowest in spring, but Ca2+ was much higher in spring than other seasons because of suspended mineral dust. In PM2.5, NO3- and K+ also showed winter maxima, but SO4(2-) and NH4+ were highest in summer. Calculations of ion equivalents showed that TSP samples were more alkaline than PM2.5, the latter being weakly acidic in winter and autumn. High sulfur and nitrogen oxidation ratios occurred in summer and autumn, and there was evidence for the formation of ammonium bisulfate in TSP, ammonium sulfate in PM2.5, and ammonium nitrate in both fractions. Comparisons with the results of prior studies indicate that pollution controls in Xi'an have reduced the levels of air pollution over the past 10 yr. The SO4

  9. Trends in cloud and rain water chemistry from 1984-2009 on Mount Washington, NH (1,534 m)

    Science.gov (United States)

    Murray, G.; Kimball, K.; Hill, L.; Weathers, K. C.

    2010-12-01

    Montane rain and cloud events were sampled between June-August from 1984-2009 at the Lakes of the Clouds (LOC) sampling site located at 1,540 m asl, 1.6 km SW of the summit of Mount Washington, NH (44° 16'N, 71° 18'W, 1,914 m ASL), and adjacent to two designated Class I areas (Great Gulf and Presidential Range Dry River Wildernesses). Non-volume weighted cloud and rain water sample concentrations for pre (H ion: 1984-1994, sulfate ion: 1984-1989) and post (1995-2009) full implementation of the 1990 Clean Air Act Amendments (CAAA) showed significantly lower hydrogen ion concentrations for the later time period (non-parametric Mann Whitney U tests p<0.001). Pre and post CAAA cloud and rain water sulfate and nitrate concentrations were not significantly different, however, ammonium levels are greater in the post CAAA time frame. A hiatus in sample analysis of anions, and most cations, from 1990-1994 may contribute to the lack of significant differences in pre and post CAAA implementation. However, there was an increase in cloud water ammonium over this time period, which may be a result of dissolution of more neutralized sulfate aerosol being incorporated into clouds. Whether the increase in ammonium concentration is due to an increase in aerosol transport to this rural mountain site is unknown. Evidence of greater ammonium sulfate and ammonium bisulfate dissolution is supported by an increase in the ratio of ammonium to sulfate in cloud water while hydrogen to sulfate ratios decreased comparatively for the pre and post CAAA time periods. A co-located filter-based aerosol measurement also shows a shift to higher ratios of ammonium to sulfate in summer daytime samples over similar time frames. This finding is mirrored at a nearby (55 km SW from LOC) but much lower (250m asl) Clean Air Status and Trends Network sampling site locate at the USFS Hubbard Brook Experimental Forest. Here, weekly samples show the ratio of ammonium to sulfate has increased, even as both ions

  10. On the composition of ammonia-sulfuric acid clusters during aerosol particle formation

    Directory of Open Access Journals (Sweden)

    S. Schobesberger

    2014-05-01

    were only observed at sufficiently high [NH3] / [H2SO4]. The H2SO4 molecules of these clusters are partially neutralized by NH3, in close resemblance to the acid-base bindings of ammonium bisulfate. Supported by model simulations, we substantiate previous evidence for acid-base reactions being the essential mechanism behind the formation of these clusters under atmospheric conditions and up to sizes of at least 2 nm. Our results also suggest that yet unobservable electrically neutral NH3-H2SO4 clusters grow by generally the same mechanism as ionic clusters, particularly for [NH3] / [H2SO4]>10. We expect that NH3-H2SO4 clusters form and grow also mostly by Δm / Δn>1 in the atmosphere's boundary layer, as [NH3] / [H2SO4] is mostly larger than 10. We compared our results from CLOUD with APi-TOF measurements of NH3-H2SO4 anion clusters during new particle formation in the Finnish boreal forest. However, the exact role of NH3-H2SO4 clusters in boundary layer particle formation remains to be resolved.

  11. 龙眼-菠萝复合果酒双酵母混合发酵研究%Study of Double Yeast Fermentation Condition in Longan-Pineapple Compound Wine

    Institute of Scientific and Technical Information of China (English)

    黄夏; 陆璐; 农志荣; 杨昌鹏; 陈智理; 石少华

    2012-01-01

    [目的]研究不同果酒酵母菌株混合发酵对龙眼-菠萝复合果酒产品质量的影响,为龙眼-菠萝复合果酒生产提供参考依据.[方法]以2种果酒酵母菌株相混合对龙眼-菠萝复合汁液进行双酵母混合发酵试验.[结果]单因素试验发现,GJJM 1.69果酒酵母与GJJM 1.67果酒酵母相互混合比单一的GIM 2.92葡萄酒酵母或其他组合的双酵母酿出的龙眼-菠萝复合果酒色香味好,酒精生成量也较高.GJJM 1.69与GJJM 1.67在龙眼-菠萝复合果酒中的双酵母发酵的最佳工艺条件为:接种量6×103个/ml、亚硫酸氢钠添加量0.006 mg/L、发酵初始糖度26%、发酵pH 3.4.[结论]研究制得的龙眼-菠萝复合果酒口感较佳,且含丰富营养成分.%[Objective] To study the impact of double yeast fermentation on the quality of longan-pinapple compound wine, so as to provide references for its production. [Method] Two kinds of fruit wine yeast strains were mixed together to lest the fermentation effect on longan pineapple compound wine. [Result] The single-factor test showed that longan-pineapple compound wine, which was made from the mixture of fruit wine yeast GJJM 1.69 and GJJM 1.67. had a better color and flavor, as well as a higher alcohol yield rate, in compared with that made from single GJM 2. 92 grape wine yeast and other combinations of the double wine yeast. The optimal conditions for the fermentation of fruit wine yeast GJJM 1.69 and GJJM 1.67 mixture in the production of longan-pineapple compound wine were 6 × 103 cells/ml inoculations, 0. 006 mg/L sodium bisulfate, 26% of initial fermentation sugar concentration and pH 3.4. [Conclusion] The longan-pineapple compound wine produced in this study had good taste and high nutrients.

  12. Role of Substrate on Quartz Cementation in Quartz Aggregates

    Science.gov (United States)

    Farver, J. R.; Winslow, D.; Onasch, C.

    2010-12-01

    Quartz cementation in quartz aggregates has been experimentally investigated. The starting material was disaggregated detrital quartz grains from the well-sorted, mature St. Peter Sandstone. The ‘as-is’ grains have patches of iron oxide coatings and some have euhedral overgrowths that contain iron oxide dust rims. In addition a set of experiments was run using grains that were cleaned by soaking in sodium hydrosulfite and sodium bisulfate solutions to remove exposed iron oxide coatings. Experimental charges consisted of amorphous silica powder (≈30 mg) to provide a source of silica for the quartz cement, AlCl3 powder (≈3 mg) to provide a tracer for Cathodoluminescence (CL) identification of cement formed during the experiment, 25 wt% NaCl brine solution (≈25 mg) to increase the silica solubility and to better mimic oil field brines, and the natural quartz grains (100-130 mg). The charges were weld-sealed in Au capsules and run in cold-seal pressure vessels at 250°C to 450°C at 150 MPa confining pressure for up to 8 weeks. After the experiments, the samples were vacuum impregnated with a low viscosity epoxy containing a blue dye. After curing, the sample charge was sawn in half along its long axis and one half was polished (to 1 micron diamond paste) for analysis. The nature and amount of quartz cement in the samples were determined by a combination of CL, light microscopy, and scanning electron microscopy. Photomosaics of the samples were created and the amount of cement, porosity, and average grain sizes were determined by point-counting. The cement formed during the experiment was easily recognized from the quartz grains (and previous overgrowths) by the difference in luminescence. The results indicate the amorphous silica powder provides a ready source for silica for quartz cementation due to its greater solubility than the quartz. The cementation rates are rapid (>14% cement formed in 2 weeks at 450°C and >7% in 8 weeks at 250°C). Compared to

  13. Highly sensitive detection of DNA methylation levels by using a quantum dot-based FRET method

    Science.gov (United States)

    Ma, Yunfei; Zhang, Honglian; Liu, Fangming; Wu, Zhenhua; Lu, Shaohua; Jin, Qinghui; Zhao, Jianlong; Zhong, Xinhua; Mao, Hongju

    2015-10-01

    amplification for the incorporation of Alexa Fluor-647 (A647) fluorophores. DNA methylation levels can be detected qualitatively through gel analysis and quantitatively by the signal amplification from QDs to A647 during FRET. Furthermore, the methylation levels of three tumor suppressor genes, PCDHGB6, HOXA9 and RASSF1A, in 20 lung adenocarcinoma and 20 corresponding adjacent nontumorous tissue (NT) samples were measured to verify the feasibility of the QD-based FRET method and a high sensitivity for cancer detection (up to 90%) was achieved. Our QD-based FRET method is a convenient, continuous and high-throughput method, and is expected to be an alternative for detecting DNA methylation as a biomarker for certain human cancers. Electronic supplementary information (ESI) available: Synthesis of CdSe/CdS/ZnS core/shell/shell QDs. Sequences of primers used for amplifying the promoter regions in bisulfate-modified DNA. Comparison of detected methylation levels in different gene promoters using the QD-based FRET method versus bisulfite pyrosequencing. Methylation levels of the RASSF1A gene in one pair of NT and cancer samples as indicated by pyrosequencing. Theoretical calculation of the Förster distance R0. See DOI: 10.1039/c5nr04956c

  14. Liquefaction of wheat straw catalyzed by acidic ionic liquid and analysis of liquefied products%酸性离子液体催化麦秸液化及其产物分析

    Institute of Scientific and Technical Information of China (English)

    关倩; 蒋剑春; 徐俊明; 王奎; 冯君锋

    2016-01-01

    With the increasing energy requirements and pollution problems worldwide, energy from renewable resources has received global attention in recent decades. Biomass is one of the most abundant renewable resources. It mainly includes forest residues, agricultural wastes, industrial residues, municipal solid wastes, bagasse, aquatic plants, and algae animal wastes. Due to the advantages of abundance, non-polluting, being renewable and easy to obtain, biomass is considered as the most promising energy feedstock to replace the traditional energy. Meanwhile, it is the only resource that can be converted into solid, liquid, and gaseous products for use of fuels. Thermo-chemical conversion is an effective technology of biomass conversion. Liquefaction is the typical thermo-chemical technology for the conversion of biomass to obtain liquid biofuels and valuable chemicals, such as bio-oil and fuel additives. The conversion process is not only influenced by organic reagents but also by different catalysts. Effective catalyst is an essential factor to improve liquefaction efficiency. As catalyst, sulfuric acid has very strong corrosion and needs high-quality liquefaction equipment, and its recycling is difficult. Solid acid is used to overcome shortcomings of organic acid in the liquefaction, but it is easy to form coke to cause the deactivation of catalyst, and needs to be calcined before re-use, which increases the reaction cost. Now, it is found that the ionic liquid has non-corrosiveness, low melting point, high thermal stability and low vapor pressure, and some other merits. It has a broad application prospect used as solvents and catalysts in catalytic reactions. Ionic liquid, especially sulfonated bisulfate ionic liquid can dissolve cellulose, because it has higher acidic sites that can easily break the hydrogen bonds of biomass material, and promote the degradation and conversion of cellulose. At present, ionic liquid is usually used to catalyze carbohydrate, which is

  15. A Randomized Clinical study of Domestic Clopidogrel Lipoic acid and Cilostazol in Treatment of Peripheral Arterial Occlusive Disease%硫酸氢氯吡格雷治疗糖尿病下肢动脉闭塞症的随机对照临床试验研究

    Institute of Scientific and Technical Information of China (English)

    李林; 何永城; 李旭盛; 李群

    2015-01-01

    目的:观察硫酸氢氯吡格雷治疗2型糖尿病( T2DM)下肢动脉闭塞( PAD)的有效及安全性。方法:入选94例糖尿病性PAD患者,按照随机数列表分为对照组48例,住院期间给予前列地尔、甲钴胺、羟基红花素注射液、西洛他唑联合治疗7~14天,出院后单独给予西洛他唑口服12周。治疗组在对照组基础上住院或出院均给予首次600mg,后150mg/d连续7天,后改为75mg/d连续8周。评价氯吡格雷治疗DM所致的PAD的临床效果、血流动力学及下肢溃疡坏死率。结果:治疗组显效率(75.0%vs 54.3%, P=0.036)、总有效率(95.8%vs 80.4%, P=0.020)均显著高于对照组,治疗组6个月内再次发生溃疡坏疽发生率为2.0%,对照组为13.0%,2组发生率具有统计学差异(P<0.05)。另外治疗组ABI改善程度(0.94±0.23 vs 0.72±0.31)、足背动脉血流速度(38.2±3.9 vs 33.5±2.8),腘动脉血流速度(68.2±8.9 vs 56.8±5.8)改善均优于对照组,2组血小板聚集率分别为(27.3±14.8%vs 38.4±12.6%),2组比较具有统计学差异(P<0.05)。治疗过程中,2组发生的不良反应无明显的统计学差异(P>0.05)。结论:氯吡格雷治疗DM所致的PAD具有一定的疗效,可用于预防下肢溃疡发生率。%Objective:To evaluate clopidogrel bisulfate cilostazol treatment of lower extremity arterial occlusive disease ( PAD) is ef-fective and safe sex .Methods:84 cases were randomly selected transluminal angioplasty or vascular reconstructive surgery is not the line of lower extremity arterial occlusive disease patients, all patients were treated conservatively , given lipoic acid mecobalamin + + +Danhong alprostadil injection , are intravenous administration, while the control group given cilostazol , clopidogrel therapy in the treat-ment group were given on the basis of the

  16. 熔解曲线法用于肺癌APC基因甲基化模式的研究%Investigation of Methylation Patterns of APC Gene in Lung Cancer with a Novel Fluorescence Melting Curve Analysis Assay

    Institute of Scientific and Technical Information of China (English)

    高丽; 潘世扬; 陈丹; 张丽霞; 谢而付; 徐建; 黄佩珺

    2012-01-01

    目的 以熔解曲线法测定4株肺癌细胞株和肺癌病人APC基因启动子区的甲基化模式.方法 以脐血淋巴细胞DNA及其转甲基后的DNA经化学修饰、克隆测序的质粒,作为完全非甲基化和完全甲基化标准品.设计通用引物,采用加入荧光染料SYBR Green I的荧光定量PCR法扩增包含21个CpG位点的APC基因启动子区的目的序列,以熔解曲线法通过与完全非甲基化和完全甲基化标准品的Tm值比较,确定四株肺癌细胞株(NCI-H446,NCI-H460,SPCA1,NCI-H520)在该区段的甲基化模式,并通过克隆测序验证.同时测定两例肺癌患者癌组织中APC基因启动子区甲基化模式.结果 四株肺癌细胞株中,NCI-H446,SPCA1和NCI-H520的Tm值与完全非甲基化标准品的Tm值相同,而NCI-H460的Tm值有两个,分别与完全非甲基化和完全甲基化标准品的Tm值吻合,并经克隆测序验证.两例肺癌患者癌组织的Tm值位于完全非甲基化和完全甲基化标准品的Tm值之间.结论 小细胞肺癌细胞株NCI-H446,肺腺癌细胞株SPCA1和肺鳞癌细胞株NCI-H520的APC基因启动子区为完全未甲基化型,而大细胞肺癌细胞株NCI-H460APC基因启动子区甲基化模式为等位基因杂合型.两例肺癌患者癌组织中的APC基因启动子均为部分甲基化型.熔解曲线法是简单、经济和实用的甲基化模式检测方法.%Objective To identify methylation patterns in the promoter region of APC gene in lung cancer cell lines and cancer patients by fluorescence melting curve analysis assay. Methods After bisulfate treatment, DNA samples of lymphocytes from cord blood without and with trans-methyl treatment were amplified. The amplicons were then cloned into plasmid vector and employed as unmethylation and methylation controls. Universal primes were designed to amplify the target sequence in the APC gene promoter region comprising 21 CpG sites. DNA melting curves were acquired by measuring the fluorescence of a

  17. Effects of sodium arsenite on hypermethylation, transcription and expression of O6-methylguanine-DNA methyltransferase gene in HaCaT cells%亚砷酸钠对HaCaT细胞MGMT基因甲基化和mRNA及蛋白表达水平的影响

    Institute of Scientific and Technical Information of China (English)

    潘雪莉; 张爱华

    2011-01-01

    Objective To investigate the DNA methylation feature and DNA methylation regulation to its transcription and expression of O6-methylguanine-DNA methyltransferase gene (MGMT) in NaAsO2-treated HaCaT cells. Methods HaCaT cells were treated 72 hours at intervals and repeatedly by 3.13, 6.25,12.50, and 25.00 μmol/L NaAsO2, MGMT gene promoter region was amplified in the transcription initiation site - 329 - + 93 region by bisulfate-sequencing polymerase chain reaction (BSP), the mRNA transcription and the protein expression of MGMT was detected by real-time quantitative PCR and Western blotting. NaAsO2-untreated HaCaT cell was set as a blank control, and human epidermal squamous carcinoma cell strain A431 was set as a positive control. Results Among the groups of HaCaT cells treated with 3.13, 6.25, 12.50 and 25.00 μmol/L NaAsO2, the positive rates of the DNA methylation of promoter region in MGMT gene were 0.63%(l/160), 6.25% (10/160), 10.63%( 17/160) and 18.75% (30/160), respectively, and methylated CpG sites were mainly located in - 249--146 region relative to transcription start site. There was no DNA methylation in the blank control. There were significant differences between the blank control and the NaAsO2-treated cells (x2 = 76.687, P< 0.05). Average levels of MGMT mRNA were 1.518 31 ± 0.180 54, 1.425 22 ± 0.180 39, 1.014 54 ± 0.096 79 and 0.887 72 ± 0.020 00, respectively among the groups of HaCaT cells treated with 3.13, 6.25, 12.50 and 25.00 μmol/L NaAsO2, compared with the blank control cells(1.198 29 ± 0.159 97), there were significant differences(F = 37.359, P < 0.05). Average levels of MGMT protein were 1.174 47 ± 0.064 75, 0.848 83 ± 0.057 01, 0.471 63 ± 0.023 34 and 0.240 34 ± 0.014 43, respectively among the groups of HaCaT cells treated with 3.13, 6.25, 12.50 and 25.00 μmol/L NaAsO2, compared with the blank control cells (1.066 19 ± 0.061 24), there were significant differences(F = 20.687, P < 0.05). Conclusions Arsenic can cause Cp

  18. ABO血型不合肝移植治疗急危重症肝病患者的临床疗效分析%Analysis of the curative effect of ABO-incompatible liver transplantation in the treatment in patients with acute severe liver disease

    Institute of Scientific and Technical Information of China (English)

    沈中阳; 邓永林; 郑虹; 潘澄; 张雅敏; 蒋文涛; 张建军; 高伟; 淮明生

    2014-01-01

    Objective To analyze and evaluate the clinical effect of ABO-incompatible liver transplantation in the treatment of acute severe liver disease.Methods A retrospective clinical study was conducted.The clinical data of 4 136 patients undergoing orthotopic liver transplantation in Organ Transplantation Center of Tianjin First Center Hospital from September 1999 to December 2013 were analyzed.The criteria of patients enrolled were as following:model for end-stage liver disease (MELD) score ≥ 20,the donor's and recipient's blood types were different,age 18-70 years,and undergone primary non-bypass orthotopic liver transplantation.According to the rate of compliance with the principles of blood transfusion,the cases were divided into two groups:ABO-compatible group (ABO-C group,n =41),ABO-incompatible group (ABO-I group,n =22).The patients in ABO-I group received basiliximab + methylprednisolone for immune induction therapy during operation,basiliximab + tacrolimus + mycophenolate + cortisol as quadruple immunosuppressive regimen after operation.They also received subcutaneous injection of low molecular heparin for anticoagulant therapy after operation,and oral warfarin or aspirin and clopidogrel bisulfate instead after 7 days.They also received routine alprostadil after operation.The remaining treatment was the same as that of ABO-C group.The clinical data,postoperative complications,rejection and survival rates of two groups were statistically analyzed.Results There were no significant differences in gender,age,MELD score,complicated with tumor,quality of donor liver,length of cold preservation of donor liver,duration of operation,and blood loss during operation between ABO-C and ABO-I groups.Number of splenectomy during operation was significantly higher in ABO-I group than that in ABO-C group (5 cases vs.1 case,x2=4.687,P=0.030).The 3-month,6-month,1-year,3-year and 5-year survival rates of ABO-C group were 89.5%,78.3%,72.5%,69.1% and 61.8

  19. 《化学通报》网络版(Chemistry Online)2001年4月论文摘要

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    有不同的反应途径,使用不同的催化剂及合成工艺。其中某些产品的三步法非光气合成已经接近成熟。催化剂性能改进和工艺过程开发是这些合成技术工业化的关键。   There are different kinds of technology for the non\\|phosgenation processes for synthesis of isocyanates according to the stage of reaction,i.e. one\\|stage,two\\|stage and three stage reactions.This review focus on the catalysts,mechanism and technologies of these processes.Three\\|stage reaction technology for synthesis of some isocyanates is about to be commercialized.The successful industrialization will depend on the development of the synthesis routes and the improvement of the performance of catalysts. [W01034] 污染生态化学与生物信息代谢* Pollution Ecology Chemistry and Biological Information Metabolism 徐维并 许后效 (中国科学院生态环境研究中心 北京 100085)   本文提出代谢信息分子新概念,并阐述了烷化核酸碱基和一氧化氮这两个代谢信息分子作为污染生态化学与生物信息代谢相互关系的表达。   This paper raised a new concept concerning the metabolic information molecule,and it was expounded that the metabolic information moleculars of both alkylated nucleic acid bases and nitric oxide as an expression ion of interrelation between pollution ecology chemistry and biological information metabolism. [W01035] 硫酸氢钠催化合成丁酸异戊酯的研究 Study on the Catalytic Synthesis of Isoamyl Butyrate by Sodium Bisulfate 刘华亭 林 进 (河北师范大学化学系 石家庄 050016)   研究了以硫酸氢钠为催化剂,丁酸和异戊醇为原料合成丁酸异戊酯,并考察了影响反应的因素。结果表明,醇酸摩尔比为1.2∶1,催化剂用量为0.5g(丁酸为0.2mol的情况下),带水剂甲苯为10mL,反应时间为1.0h是最适宜的反应条件,酯化率达99.2%。