甜菊醇和异甜菊醇与DNA作用方式的研究

甜菊醇是新型甜味剂甜菊糖在人体内的代谢产物,在酸性环境中可重排成异甜菊醇,它们都是重要的药物合成中间体.研究甜菊醇和异甜菊醇与DNA的作用方式有助于理解其药理或细胞毒性.以小牛胸腺DNA(CT-DNA)为模板,通过考察甜菊醇和异甜菊醇对CT-DNA熔点和粘度的影响,以及甜菊醇和异甜菊醇与CT-DNA体系紫外吸收的变迁,初步推断甜菊醇和异甜菊醇都是以沟槽方式与CT-DNA结合;异甜菊醇与CT-DNA的作用比甜菊醇与CT-DNA作用强.     

异甜菊醇及其衍生物的合成与应用研究进展

甜菊糖苷是一种天然甜味刑,在酸性条件下水解为异甜菊醇。异甜菊醇具有降血压、降血糖、抗炎和抗肿瘤等生理活性。本文对异甜菊醇及其衍生物在抗炎、抗肿瘤、手性催化和分子识别方面的应用研究进行了总结。     

异甜菊醇药理活性研究进展

异甜菊醇具有广泛的药理活性,在降低血压、抗肿瘤、抗心肌缺血复灌损伤等方面具有重要功效,实验表明其还对受体种子具有萌发作用并且能作为一种新的胰岛素增敏剂用于治疗Ⅱ型糖尿病。因为异甜菊醇本身特有的二萜骨架,它可作为药物合成中常用的活性框架。本文对异甜菊醇结构修饰和改造及药代学活性研究进行了综述。     

盐酸或氨基磺酸催化水解斯替夫苷制备甜菊醇

分别以盐酸或氨基磺酸为催化剂水解斯替夫苷(St),研究底物质量浓度、反应温度、催化剂用量和反应时间对斯替夫苷水解的影响,着重考察了斯替夫苷的转化率、甜菊醇的产率和异甜菊醇的产率。其中,盐酸催化水解斯替夫苷的最优工艺条件为:反应温度95℃,底物质量浓度400 g/L,盐酸浓度0.04 mol/L,反应时间28 h;在该条件下,根据高效液相色谱分析计算得到斯替夫苷转化率接近100%,甜菊醇产率达83.6%,异甜菊醇产率达12.4%。氨基磺酸催化反应的工艺条件为:反应温度95℃,斯替夫苷质量浓度400 g/L,氨基磺酸浓度0.05 mol/L,反应时间31 h;在该条件下,根据高效液相色谱分析计算得到斯替夫苷转化率接近100%,甜菊醇产率达81.5%,异甜菊醇产率达11.7%。     

化学-酶法制备手性菊酯农药的关键技术及产业化

正一、项目简介在国家863, 973、科技攻关等项目资助下,开发了化学一酶法合成手性菊醋农药新技术,针对S一生物烯丙菊醋、苯氛菊醋等手性菊醋的关键中间体一手性菊醇的合成关键问题,利用有机溶剂中的生物催化技术成功制备单一构型手性菊醇.解决了上述技术难题,实现手性菊醋的规模化制备。授权专利情况:申请国家发明专利8项,已授权4项,发表论     

原醋酸三乙酯的合成研究

原醋酸三乙酯是有机合成的原料,应用于医药、农药的合成中。特别在异戊烯醇—原醋酸酯法(相模法)和三氯乙醛—原醋酸酯法(相模—库拉莱法)合成二氯苯醚菊酯中,是制备二氯菊酸不可缺少的中间体。目前国内二氯苯醚菊酯的生产主要     

采用酶法生产除虫菊酯

McGraw-Hill 的生物技术新闻发布人报道,酶法生产无毒的杀虫剂除虫菊酯不久将由Mclaughlin Gormley King 公司取得专利。该方法采用来自无细胞菊花均浆的固定化酶,把甲羟戊酸或焦磷酸异戊酯转化成除虫菊酯和菊醇。在传统上,除虫菊酯唯一的生产方法     

产品开发

高碳增塑剂醇开发前景好目前国内外增塑剂醇以正丁醇、异丁醇、辛醇、异壬醇、异癸醇为主,其次是2-丙庚醇和C6～C11直链醇等。我国目前增塑剂醇品种少,只有正丁醇、异丁醇和辛醇,其他增塑剂醇如异壬醇、异癸醇、2-丙基庚醇等目前基本上还没有生产,市场需求基本上全靠进口。在全世界增塑剂醇的总消费量中,正丁醇、异丁醇、辛醇共约占76%,异壬醇约13%,异癸醇约4%,2-丙基庚醇约2%。因此开发生产异壬醇、异癸醇、2-丙基庚醇等高碳增塑剂醇前景看好,是增塑剂醇的开发方向。     

(±)-β-甜没药烯和(±)-α-甜没药醇的全合成

本文报导了一条从异戊二烯(Ⅰ)和甲基乙烯基酮(Ⅱ)出发全合成(±)-β-甜没药烯(Ⅴ)和(±)-α-甜没药醇(Ⅵ)的路线。Ⅰ和Ⅱ经Diels-Alder反应得到酮Ⅲ,Ⅲ和异戊烯氯经烷基化反应得酮Ⅳ。Ⅳ分别经Witting反应和Grignard反应得到Ⅴ和Ⅵ,总得率为15.9%和16.7%。     

酵母抽提物对10种甜味剂的增甜作用分析

为探究增甜型酵母抽提物对10种甜味剂甜味的影响，采用高效液相色谱仪和氨基酸自动分析仪对增甜型酵母抽提物中的游离氨基酸、5’-核苷酸和有机酸主要滋味物质进行了定量分析；通过滋味活度值（TAV）评价滋味成分对甜味的贡献。结果表明，增甜型酵母抽提物中共鉴定出13种TAV>1的滋味物质，对滋味的贡献较大；添加质量浓度为0.1 g/L的增甜型酵母抽提物可显著增强甜菊糖苷、罗汉果甜苷和三氯蔗糖的甜味；添加质量浓度为0.1 g/L的增甜型酵母抽提物可以使甜菊糖苷达到最大甜度感知的时间提前了2.98 s；谷氨酸、丙氨酸均可显著增强甜菊糖苷、罗汉果甜苷和三氯蔗糖的甜度感知，柠檬酸可显著增强三氯蔗糖的甜度感知。分子对接结果表明，当谷氨酸或丙氨酸存在时，甜菊糖苷与味觉受体1型成员2之间的疏水相互作用增加。     

Occurrence,abundance and origin of minerals in coals and coal ashes

The mineralogy of coal and coal ash samples from a wide variety of deposits worldwide has been studied by X-ray diffractometry, light microscopy, SEM, TEM, and DTA-TGA methods. The common major minerals identified in the crystalline matter of coals are quartz, kaolinite, illite, calcite, pyrite, plagioclase, K-feldspar and gypsum, and occasionally dolomite, ankerite, siderite, Fe oxyhydroxides and sulphates. A number of minor and especially accessory minerals are also present. The modes of occurrence and some genetic peculiarities of the minerals found are described and summarized. Minerals and phases of probable detrital origin include mainly silicates, volcanic glass, oxyhydroxides and phosphates. Authigenic minerals of syngenetic origin may be sulphides, clay minerals, carbonates and rarely sulphates and phosphates. Epigenetic minerals, formed by the infiltration of low-temperature hydrothermal solutions, may include sulphides, carbonates, sulphates, clay minerals, quartz, chlorides, and probably alkaline-earth hydroxides and zeolites. The alteration products of detrital and authigenic minerals may be Fe and Al oxyhydroxides, sulphates, kaolinite, illite, chlorite, muscovite, zeolites and calcite. The behaviour of these minerals and phases during low- and high-temperature ashing is also discussed.     

Some gas phase reactions during the firing of magnesite-chromite refractories in a tunnel kiln

Conclusions A correlation is shown between the high-temperature, physicochemical processes in basic refractories, changes and reactions in the gaseous phase, and the nature of the wear of the roof of a tunnel kiln.As a result of dissociation, oxidation, and volatilization the waste gases are enriched with vapors of alkalis, CrO₃, sulfur trioxide, and oxides of iron and magnesium, and become corrosive with respect to the kiln lining. The reaction of the oxides vapors with each other and with the lining of the roof and their condensation determines the nature of the wear in the magnesite-chromite refractories, the chemical and mineral compositions of the resulting deposits and crusts. The main source of alkalis and sulfur trioxide is the sulfite yeast dregs (sulfite lye) present in the goods being fired.We determined the temperature relationship with the composition and amounts of deposits and crusts. Carcase and skeletal deposits and crusts formed on the firing section of the kiln, mainly periclase and spinel compositions; in the warming-up section the deposits were brittle, granulated, consisting of sulfates, chromates, chromium oxide, periclase, and spinels.It was found that the deposits on the walls of the pores in the MKhS refractories consist of sulfates and chromates, forming solid solutions.Translated from Ogneupory, No. 5, pp. 13–16, May, 1980.     

我国橡胶防老剂和促进剂的进出口情况

介绍近年来我国橡胶防老剂和促进剂进出口情况。2013年,我国防老剂和促进剂进口量分别为19046.61 t和14984.44 t,同比分别增长16.12%和11.64%;进口金额分别为6202.02万美元和7391.97万美元,同比分别增长14.76%和1.39%;出口量分别为29070.40 t和89942.59 t,同比分别增长62.68%和45.72%;出口金额分别为6794.43万美元和27885.34万美元,同比分别增长60.45%和50.17%。我国进口防老剂主要来自中国大陆(以国货复进口形式进口)、美国、韩国以及中国台湾省等,进口促进剂主要来自中国台湾省、美国、韩国、日本以及德国等,防老剂主要出口日本、泰国、印度尼西亚和韩国等,促进剂主要出口美国、韩国、巴西、泰国和日本等。     

松香基表面活性剂研究进展

松香是一类产量丰富、价格低廉的可再生林产资源,被广泛地应用于食品、农业、橡胶、油墨、涂料等领域。松香的三环二萜结构具有超强的疏水性,通过催化异构、Diels-Alder加成等手段引入亲水基团可制备高附加值、易生物降解的绿色表面活性剂。本文从阴离子、阳离子、非离子和两性离子表面活性剂4个大类对松香基表面活性剂应用的文献及专利进行综述,重点分析了羧酸盐、磺酸盐、硫酸盐和磷酸盐4种阴离子型表面活性剂和季铵盐阳离子型表面活性剂,多元醇型和聚氧乙烯型非离子表面活性剂,以及甜菜碱型和氧化胺型两性离子表面活性剂。剖析松香基表面活性剂产业化开发的新技术及新产品概况,提出松香基表面活性剂替代传统表面活性剂的潜在应用领域。同时,对松香基表面活性剂的研究发展与产业化发展进行了评价与展望。     

Effects of nutrition and origin on the amino acid,grease, and suint composition and color of cashmere and guard hairs

Nutritional and environmental effects on the amino acid, wax, and suint contents and color of raw cashmere were investigated. Cashmere was obtained from goats fed with or without dietary protected protein, goats fed different levels of dietary energy and feeds, and goats from Australia, China, and Iran. The determined attributes included the production, diameter, length, fiber curvature, crimp, wax and suint contents, amino acid composition, lightness, and yellowness of cashmere. The content of suint, but not that of wax, was affected by nutrition management. The amino acid composition of cashmere was affected by the energy and protein nutrition, feed type, and country of origin. The amino acid composition of cashmere was different from that of guard hair. The lightness and yellowness of cashmere was affected by the nutrition treatment, grazing, cashmere production, and sum of the wax and suint contents of the raw cashmere. The variation in the amino acid composition of cashmere likely affected both its physical and chemical reactivity. Nutrition manipulation of cashmere goats and the origin of goats have implications with respect to the properties of cashmere as changes in fiber cell biosynthesis can alter the amino acid composition of the fiber. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

轻质隔热吸音仿石漆研制、性能及施工

轻质隔热吸音仿石漆是传统仿石漆的升级产品,其具有质轻、隔热、吸音、环保等特点,是一款集节能、降噪、装饰等多功能于一体的新产品,特别适合保温墙面、旧墙面等装饰装修工程.主要讨论了仿石骨料颗粒级配、乳液、增稠剂、成膜助剂、消泡剂等对轻质隔热吸音仿石漆质量的影响,测试了轻质隔热吸音仿石漆的主要性能,介绍了轻质隔热吸音仿石漆施工工艺要点.     

Properties of poly(alkylene oxide) elastomers

The catalyst comprised of triisobutylaluminum, zinc acetylacetonate, and water was used to prepare homopolymer of epichlorohydrin; copolymers of epichlorohydrin with propylene oxide, ethylene oxide, and allyl glycidyl ether; and terpolymers of epichlorohydrin, propylene oxide, and allyl glycidyl ether and of epichlorohydrin, ethylene oxide, and allyl glycidyl ether. The vulcanizates of these rubbers provide variations of stressstrain and dynamic properties, freeze point, hardness, and solvent resistance depending on the type and amount of comonomer. In general, these rubbers have excellent heat, ozone, and oxidation resistance as well as oil and solvent resistance.     

Gossypol and gossypurpurin in cottonseed of different varieties ofG. barbadense andG. hirsutum,and variation of the pigments during storage of the seed

Summary Selected varieties of cottonseed comprising three Sea Island cottons, four Egyptian cottons, and 10 upland cottons providing two or more varieties having the following characteristics: short, intermediate, and long staple; low, intermediate, and high content of lipids; and low, intermediate, and high content of protein, were planted and grown under as nearly identical conditions as possible. The initial contents of moisture, lipids, nitrogen, gossypol, and gossypurpurin of the harvested seed were determined, after which samples of all of the seed were stored for a year under identical conditions and analyzed periodically for gossypol and gossypurpurin. A definite relation was found between the species of the seed and their content of gossypol and gossypurpurin. Sea Island and Egyptian seed of the speciesG. barbadense contained more gossypol and very much more gossypurpurin than seed of the speciesG. hirsutum. Within the speciesG. barbadense Sea Island seed contained more gossypol and less gossypurpurin than Egyptian seed. Gossypurpurin increased during storage of all of the seed whereas gossypol varied in a number of different ways, increasing in some, decreasing in others, and remaining relatively constant in a few samples of stored seed. A discussion is presented of the theoretical and practical implications of these observations. Presented at 39th Annual Meeting of the American Oil Chemists' Society in New Orleans, May 4–6, 1948. One of the laboratories of the Burean of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture. Bureau of Plant Industry, Soils, and Agricultural Engineering, Agricultural Research Administration, U. S. Department of Agriculture.     

Relative FFA formation and lipid oxidation of commercially milled unseparated,head, and broken rice

This study was conducted to determine the relative rate of FFA formation and lipid oxidation of unseparated (head and broken), head, and broken rice and the effect of water washing on the lipid quality of broken rice. A regression model was developed with surface FFA or conjugated diene (CD) content vs. incubation time to determine the rates of FFA formation and lipid oxidation. The surface lipid contents of unseparated, head, and broken rice were 0.40, 0.38, and 0.50% of rice, respectively. FFA formation during storage showed three phases: an initial rapid formation, followed by a period of very little or no formation, and finally a phase of gradual formation. In contrast, CD formation initially showed a slow increase but later increased gradually with storage time. The relative rates of FFA and CD formation of unseparated, head, and broken rice were 0.0028, 0.0027, and 0.0036 and 0.192, 0.188, and 0.377, respectively. Water washing reduced the rates of FFA formation and lipid oxidation of broken rice to 0.0015 and 0.2192 from initial values of 0.0031 and 0.369, respectively. Water washing appears to be a simple and practical means of lowering the rates of FFA formation and lipid oxidation in broken rice.     

Polymeric fibre composites, basic types, principles of fabrication, and properties. Part 5. Effect of performance effects on polymeric fibre composites; safety/hazardousness characteristics

The principles of materials science of polymeric fibre composite materials (PFCM) containing different reinforcing fibrous fillers (short-cut fibres, paper, yarn, tow, sliver, fabrics, and nonwoven materials) and different matrices (thermoplasts and thermosets) are examined in an analytical review [Khim. Volokna, No. 4 and 5 (2005); No. 1, 4, and 6 (2006)]. The mutual effect and reaction of the components of PFCM fibres and matrices) are analyzed, information is reported on the fabrication and properties of different kinds of composites: fibre-filled molding materials, pertinaxes, textolites, unidirectional composites, honeycomb plastics, etc. New types of composites with ultrahigh mechanical and thermal characteristics are examined. Testing methods and the functional properties of PFCM are examined: mechanical, thermophysical, electrophysical, optical. The mechanisms of the changes in the structure and properties of PFCM under external effects: thermal, photochemical, ionizing radiation, active media, and other factors, are analyzed. Performance reliability indexes are examined, including aging and the effect of extreme conditions. Safety/hazardousness characteristics are very important in selection of PFCM and use of articles made from them: sanitary-hygienic and toxicological, combustibility and toxicity of products of combustion. The following features of polymeric fibre composites in comparison to other materials are summarized below based on the examination: — Combination of different kinds of fibre fillers and matrices (binders) allows regulating the properties of PCM in a wide range, selecting the optimum indexes for items with a wide spectrum of applications. — Items made of PFCM involve low specific consumption of materials and are easy to manufacture, process, and treat in comparison to many traditional materials, metals and ceramics in particular. — Articles made from composites are reliable in use, almost not subject to corrosion, and do not require special protection or periodic painting of the surface. — With respect to specific mass characteristics, PFCM can be many times better than items made of metals and other traditional materials. This is important for using them in vehicles, aircraft, rescue craft, and sporting goods. Due to the features of the properties and the positive performance characteristics, PFCM have a great future in the most varied areas of application. __________ Translated from Khimicheskie Volokna, No. 6, pp. 26–40, November–December, 2006.