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1.
MSDS与化工企业的国际接轨   总被引:3,自引:0,他引:3  
化学品安全说明书(MSDS)和化学品安全注意事项商标警语(Warning Label)是化工企业融入全球经济的重要法律规范,是化工产品出口北美和国内销售的通行证,是化工企业必须掌握的国际法律规范。本文论述了编制和应用MSDS、Warning Label的重要性以及MSDS和WarningLabel的内容和要求  相似文献   

2.
Isomerization of isopropylidene glycerol ketals and benzylidene glycerol acetals was studied, and isoraerization equilibria were established. Reaction of benzaldehyde with glycerol gave four benzylidene glycerol isomers, which were separated by column chromatography and characterized by NMR spectroscopy and other methods. Isomerization of 1- and 2-monoglycerides and of 1,2- and 1,3-diglycerides, and their separation by column chromatography, are described. Mechanisms of isomerization in mono- and diglycerides and factors which affect them are discussed. Isomerization of 1- and 2-glycerophosphates and of cyclic glycerophosphates by acid and base was also studied. Hydrolysis products of L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine were separated by column chromatography and characterized by periodic acid oxidation, optical rotation, and NMR spectroscopy. No isomerization of unhydrolyzed L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine was observed. Evidence indicated that acid-catalyzed hydrolyses of phosphoglycerides are under thermodynamic control whereas most base-catalyzed hydrolyses are under kinetic control.  相似文献   

3.
The percentage contents of oil and protein in the seeds of Calotropis gigantea Linn. (Asclepiadaceae), Acacia caesia Willd., syn. A. intsia (Leguminosae) and Abelmoschus ficulneus Wight & Arm., syn. Hibiscus ficulneus Linn. (Malvaceae) were 30.8, 8.8 and 14.4, and 19.0, 11.7 and 20.0, respectively. The major fatty acid was 18:1 in C. gigantea and 18:2 in the other two seeds oils. Malvalic, sterculic and dihydrosterculic acids were present in small quantities in A. ficulneus seed oil. The major essential amino acids in the seed proteins were phenylalanine, lysine and histidine in C. gigantea, threonine and arginine in A. caesia and lysine and phenylalanine in A. ficulneus.  相似文献   

4.
Annona squamosa and Catunaregam nilotica seeds and oils were characterized for their approximate analysis and physico-chemical properties. The oil and protein contents were 26.8, 17.5 and 40.0, 22.2%, in A. squamosa and C. nilotica seeds, respectively. The oils were extracted using cold extraction (CE) and Soxhlet extraction (SE) methods. Fatty acids and tocopherols were determined by GC–MS and HPLC, respectively. Generally the physico-chemical properties and fatty acids were not significantly (P ≤ 0.05) affected by the extraction methods. The major fatty acids of A. squamosa oil extracted by CE and SE were oleic 49.2 and 50.5%, linoleic 22.3 and 22.7%, palmitic 15.6 and 15.2%, and stearic 10.6 and 9.3%, respectively. While the major fatty acids in C. nilotica oil extracted by CE and SE were oleic 10.5, and 10.4%, linoleic 63.1 and 63.4%, palmitic 9.7 and 9.8% and stearic 5.1 and 5.4%, respectively. The tocopherol content of CE and SE extracted oils from A. squamosa amounted to 16.6 and 15.5 and from C. nilotica amounted to 110.5 and 107.7 mg/100 g oil, respectively, with delta-tocopherol as the predominant tocopherol in A. squamosa oil, and beta-tocopherol in C. nilotica oil. The total amount of amino acids was found to be 7.266 and 14.202 g/100 g protein, in seeds of A. squamosa and C. nilotica, respectively.  相似文献   

5.
Polycaprolactone is fully bioresorbable and biocompatible material. Liposomes containing nanocopper, nanosilver, and nanogold are known to have antifungal and antibacterial properties and to further aid in the synthesis of collagen and elastin in the skin. It is possible to combine the properties of polycaprolactone fibers and liposomes in new approaches to deliver active substances through cosmetics and medicines. The aim of the research was to examine the possibility of simple modification of PCL fibers with use of nanocopper, nanogold, and nanosilver incorporated liposomes. The size and the type of the liposomes were examined using optical microscopy and DLS techniques. The fibres modified with liposomes were investigated using SEM and FTIR techniques. Additionally the contact angle measurements were performed. The study shows an innovative method of modifying polycaprolactone nonwoven textiles. This combination of PCL fibers and liposomes allows easy and efficient preparation and delivery of active substances to a particular location. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43299.  相似文献   

6.
Natural and physical sciences are based on determinable facts. What is ethical, as distinct from illegal, is largely a matter of opinion. Scientific and industrial activities related to ancient and modern biotechnologies are among the most critically scrutinised for ethical probity by social activists and journalists. The practices and products of biotechnologies should be judged both deontologically – by motivation and intention, and teleologically – by determinable consequence. Bioethical criteria have been proposed by governments, medical practitioners and philosophers for many centuries. During the past decade, various scientifically competent organisations, national and international, have formulated comprehensive protocols by which to determine effectiveness and safety of novel foods, pharmaceuticals and other biologicals, including those derived from genetically modified organisms. Means and opportunities by which to satisfy the health and nutritional needs of impoverished nations and communities differ significantly from those who enjoy greater affluence. It is distinctly unethical for Europeans and North Americans, whose food and health securities are not at risk, to impose their ethical predilections on poorer nations. Equally reprehensible are the diverse tariff and non‐tariff barriers to equitable international trade, and acts of biopiracy inflicted upon poorer nations. As a wise Asian sage has observed, the planet's resources and scientific ingenuity are sufficient to satisfy everyone's need, but not everyone's greed. Present and predictable world‐wide demand for bioscientists and bioengineers exceeds best estimates of supply. Systematically planned, long‐term investments by governments and bioindustries to generate adequate qualified men and women are urgently needed. © 2002 Society of Chemical Industry.  相似文献   

7.
The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers’ demands while searching for ‘clean label’ food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes’ ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes’ incorporation into processes has limitations and is regulated by national and international levels.  相似文献   

8.
Lactic acid bacteria (LAB) are significant groups of probiotic organisms in fermented food and are generally considered safe. LAB regulate soil organic matter and the biochemical cycle, detoxify hazardous chemicals, and enhance plant health. They are found in decomposing plants, traditional fermented milk products, and normal human gastrointestinal and vaginal flora. Exploring LAB identified in unknown niches may lead to isolating unique species. However, their classification is quite complex, and they are adapted to high sugar concentrations and acidic environments. LAB strains are considered promising candidates for sustainable agriculture, and they promote soil health and fertility. Therefore, they have received much attention regarding sustainable agriculture. LAB metabolites promote plant growth and stimulate shoot and root growth. As fertilizers, LAB can promote biodegradation, accelerate the soil organic content, and produce organic acid and bacteriocin metabolites. However, LAB show an antagonistic effect against phytopathogens, inhibiting fungal and bacterial populations in the rhizosphere and phyllosphere. Several studies have proposed the LAB bioremediation efficiency and detoxification of heavy metals and mycotoxins. However, LAB genetic manipulation and metabolic engineered tools provide efficient cell factories tailor-made to produce beneficial industrial and agro-products. This review discusses lactic acid bacteria advantages and limitations in sustainable agricultural development.  相似文献   

9.
以山核桃、油茶和板栗3类果蓬为原料,研究了此类原料与杉木、松木屑在不同配比条件下对果蓬类致密成型特征及其机制炭质量的影响。证实了果蓬类原料因纤维素含量、木质素含量与杉木、松木存在差异,且因较高的灰分含量限制,需与杉木或松木屑等原料在一定配比条件下才可实现良好的致密成型。而配比选择试验结果则表明,果蓬原料与杉木、松木屑混合原料以3:7比例配料为宜;在此条件下,制备的机制炭外形平直无裂缝,得率为 33.85%~36.73%,固定碳含量 79.80%~86.20%,热值28.96~31.92 MJ/kg。  相似文献   

10.
Methods of nitride production are summarised and their thermodynamics surveyed. Crystal structures and types of bonding in binary and ternary nitride compounds are classified and discussed. Kinetics of nitride formation are related to structural changes in the materials, which control diffusion of metals and nitrogen and cause nitride scaling. Metal nitridation with ammonia and nitride formation during ammonia synthesis are discussed. Information so far available on the sintering of nitrides and its effect on their chemical reactivity is reviewed. This effect is influenced by additives or impurities such as oxides formed by partial nitride hydrolysis and oxidation. Sintering and hot pressing increase the resistance of nitrides to hydrolysis and oxidation, so that they become more suitable for use as refractories. Often, corrosion resistance of nitride layers on metal surfaces is impaired by poor scaling resistance in air or oxygen at comparatively low temperatures. The kinetics and products of oxidation of nitrides so far studied, notably AlN, TiN and UN, depend mainly on the intrinsic reactivity of the material and the available surface at which oxidation can occur. Subsequent work will be concerned with changes in phase composition, surface area and crystallite and aggregate sizes and their correlation with production, sintering, hydrolysis and oxidation conditions for single and mixed nitrides. Suitable experimental techniques are summarised in this paper.  相似文献   

11.
《云南化工》2015,(2):44-46
采用高效液相色谱法,使用Diamonsil-C18色谱柱和紫外检测器,在254 nm波长下对磺草酮、莠去津进行分离和定量分析。结果表明,该方法磺草酮、莠去津的线性相关系数分别为R2=0.9989、R2=0.996;磺草酮、莠去津的标准偏差分别为0.06、0.15;磺草酮、莠去津的变异系数分别为0.54、0.49;磺草酮、莠去津的平均回收率分别为100.1%、100.0%。  相似文献   

12.
It remains both a challenge and an opportunity to attract and nurture the best talent in ceramic science and engineering. Success stories in other areas provide examples of how to do it. Research findings reveal behaviors and specific actions that encourage excellence in all individuals, for example, showing support, creating structures that promote interaction, and establishing clear expectations. In developing countries, where the education and research infrastructure are often not as strong and English is not otherwise the language of choice, additional factors come into play. Involving students in research and exchanges—both domestically and internationally—within academe and with other sectors are keys to maintaining a high level of engagement. Students need to identify with the benefits and goals of their career paths. It is imperative that the education curriculum be nimble and incorporate skill development in important and emerging areas such as entrepreneurship and integrated computation and modeling.  相似文献   

13.
Seventeen periodic kilns were studied for construction and design details, operation, and results. Eleven were round and six were rectangular. Alterations were made in grate area proportions, floor openings, flue design, and dimensions; the firing conditions and quality of ware obtained with each were recorded. The data obtained show effect on heat distribution and on time and fuel expenditures. Detail designs of flues are shown and the data are in tables and graphs. Detail specification and bill of materials are given for the 30-foot round kiln which was found to give best results in ware and costs.  相似文献   

14.
Seeds ofCrambe abyssinica C.D. 6619 and theBrassica napus varieties Golden and Zero-erucic were collected at different stages of maturity and the free lipid extracted with hexane. The lipid thus obtained was separated into lipid classes by silicic acid column chromatography. The lipid classes were further examined by thin-layer chromatography and the component fatty acids and sterols by gas-liquid chromatography. The relative amounts of the lipid classes in crambe and both rape varieties varied as the seed matured and a period of great change occurred about 10 days after fertilization. The greatest change was in triglycerides and phospholipids plus glycolipids. Free fatty acids, present in immature seeds, has almost disappeared at maturity. The lipid classes of crambe and both types of rape were in similar proportion at maturity. Differences in phospholipid and glycolipid composition were found between crambe and rape and between immature and mature rape. The fatty acid composition differred between lipid classes and changed with maturity. Changes in 18-carbon acids of Zero-erucic rape were concurrent with the development of erucic and eicosenoic acids in Golden rape. Contribution No. 36 of the Food Research Institute. Presented at the AOCS Meeting, Cincinnati, October 1965.  相似文献   

15.
Temperature and precipitation variables during linear seed fill are known to be environmental determinants of protein and oil composition of the soybean [Glycine max (L.) Merr.] seed. However, the contribution of other precipitation and temperature events during the growing season and a method that would determine the precipitation and temperature variables most related to protein and oil concentration values of the seed has not been fully explored. The former was evaluated by comparing monthly temperature and precipitation variables of the growing seasons to protein and oil data for the years 1959 to 1996 from three locations listed in the Uniform Soybean Tests, Northern Region. The data set comprised locations from Maturity Groups II and III and consisted of 186 location-years. Classification and regression “tree-based” analysis were conducted to determine the month, environmental variable, and “splitting” points that correctly classified most of the 186 location-years for below-vs.-above-median protein or oil composition. The protein concentrations from the location-years were separated into these two median-boundary categories most readily by temperature variables from the months of April and August. The oil concentrations from the location-years were classified best by August and September temperature variables and precipitation in May and September. The sum of protein and oil concentrations from the location-years were best separated by August and July temperature variables and precipitation in May and July. The protein-to-oil ratios from the location-years were best separated by September precipitation and July and June temperature variables. These data demonstrate that tree-based models can use monthly temperature and precipitation variables during linear seed fill and other specific months of the crop year and relate them to the final protein and oil concentration in the seed. These results could be used by the processing industry to estimate seed composition before harvest.  相似文献   

16.
Identification of Polymers in Cosmetic Products II: Spectrometric Analysis of Plastics Synthetic polymers are increasingly used in cosmetics as film-forming agents, as viscosity and moisture regulators and as dispersion stabilizers. Their detection by precipitation and colour often is tedious and not unambiguous. In contrast to these methods, infrared, nuclear magnetic resonance and mass spectrometry frequently permit a rapid and detailed characterization of unknown plastics w. r. t. their composition and microstructure. The efficiency of these methods in the analysis of plastics is demonstrated and the spectra of some polymers and copolymers being essential for cosmetics are compared and discussed.  相似文献   

17.
Studies on the Sulphochlorination of Paraffins. III. 1H- and 13C-N.M.R. Spectra of Aliphatic and Cycloaliphatic Mono- and Disulphonylchlorides Isomeric monosulphonylchlorides of propane, butane, and heptane as well as disulphonylchlorides of propane, butane, and pentane are measured 1H- and 13C-n.m.r.-spectroscopically. Including several other aliphatic and cycloaliphatic sulphonylchlorides, the use of n.m.r. spectroscopy to identification and estimation of the composition of mono- and disulphonylchloride mixtures is discussed.  相似文献   

18.
Cycloaliphatic C21 di- and C22 tricarboxylic acids were prepared by the Diels-Alder reaction of dehydrated castor oil (DCO) fatty acids (containing 48% conjugated and 42% nonconjugated dienes) with acrylic and fumaric acids, respectively. The reaction temperature, time, catalyst concentration, and mole ratio of reactants were varied to get maximum yields of the di- and tricarboxylic acids. The unreacted DCO fatty acids were removed from the products by partition between aqueous methanol and n-hexane. The products were converted to methyl esters and characterized as the substituted cyclohexene derivatives before and after dehydrogenation with Pd/C in xylene, hydrogenation with Pd/C in decalin and oxidation with periodate-permanganate reagent and by mass and proton nuclear magnetic resonance spectrometry. The acids were converted to sodium soaps, mono- and diethanolamides and the corresponding diol and triol sulfates, and the resulting products were evaluated for their surface-active properties. The sodium soaps showed better calcium tolerance and poorer foaming power than sodium oleate. The diethanolamides were inferior to lauroyl diethanolamide in wetting and emulsifying power. The monoethanolamides were better than the respective diethanolamides and lauroyl diethanolamide in wetting property. The diol and triol sulfates were poorer in wetting and emulsifying ability and better in calcium tolerance than sodium lauryl sulfate.  相似文献   

19.
《Ceramics International》2023,49(8):12201-12213
Tetracycline (TC) and oxytetracycline (OTC) are antibiotic compounds increasingly detected in various water sources. In this study, Fe-metal organic framework incorporated biopolymer-clay hydrogels (CAMIL-MMT and CAMIL-SEP) were prepared to remove TC and OTC from water. The physicochemical properties of the as-prepared hydrogels were thoroughly characterized, and the effect of various operating parameters on the adsorption performance was systematically examined. The CAMIL-MMT hydrogel showed the maximum adsorption capacity for TC and OTC (24.59 and 26.14 mg/g, respectively) compared to the CAMIL-SEP and other forms of biopolymer hydrogel precursors. The effects of the contact time and initial concentration on TC and OTC adsorption by CAMIL-MMT and CAMIL-SEP hydrogels were well suited to the pseudo-second-order kinetics and Freundlich isotherm models. The adsorption performance of CAMIL-MMT and CAMIL-SEP hydrogels slightly decreased with an increase in solution pH, while it was not much influenced by the co-existing anions. The thermodynamic study indicated that the reactions for the uptake of TC and OTC were spontaneous and highly favorable. Moreover, the as-synthesized CAMIL-MMT and CAMIL-SEP hydrogels demonstrated strong potential for reuse in TC and OTC removal with high reusability and strong stability. The photocatalysis study revealed that residual TC and OTC after adsorption could be further degraded by CAMIL-MMT and CAMIL-SEP hydrogels under visible light irradiation. From the above-mentioned results, the as-synthesized CAMIL-MMT and CAMIL-SEP hydrogels are promising to be considered alternative materials for the adsorptive and photocatalytic removal of TC and OTC in practical application of water and wastewater treatment.  相似文献   

20.
Skeletal structure and body composition may be altered permanently in response to aggressions during critical periods of growth. This increases propensity to adverse effects in adulthood. The study explored the association of anthropometric variables of body size and proportions and of body composition with systolic (SBP) and diastolic (DBP) blood pressure (BP) in young adults. We studied 166 men and 246 women age 20-34. SBP, DBP, weight, stature, sitting height, circumferences (waist, hip), breadths (biacromial, biiliac) and skinfolds (bicipital, tricipital, subscapular, suprailiac) were assessed. BMI, waist-hip ratio (WHR), waist-stature ratio, and Sigma skinfolds-stature were calculated. Pearson correlations were determined for anthropometric variables with SBP and DBP and linear regression models for SBP and DBP were developed by sex. Correlation coefficients between indicators and BP were significant, except for stature and SBP and DPB, and WHR with DBP in women; and stature with DBP, biiliac breadth and WHR with SBP, and sitting height with SBP and DPB in men. SBP and DPB were explained by weight, BMI, and biiliac breadth in multivariable analysis in women, where 15.4% and 10.8% of variance of SBP and DPB was explained. In men, SBP was explained by weight, Sigma skinfolds and WHR, and DBP by Sigma skinfolds; models explained almost 20% of SBP and DPB variance. No association was found between BP and past malnutrition indicators. Biiliac breadth, weight and BMI in women, and weight, WHR and Sigma skinfolds in men explained BP. The use of biiliac breadth in the assessment of hypertension risk in women should be explored further.  相似文献   

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