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1.
Despite the large number of elaborate enantioselective syntheses for the preparation of a single enantiomer to achieve industrial and scientific goals, the separation and purification of enantiomers (components of racemic compounds) is also necessary. Hence, we present the most often used thought-provoking modern methods based on momentous recognitions (e.g. spontaneous resolution, induced crystallization, resolution by formation of diastereomers, resolution by formation of non-covalent diastereomers, resolution by diastereomeric salt formation, resolution by diastereomeric complex formation, "half equivalent" methods of resolution, separation by crystallization, separation by distillation, separation by supercritical fluid extraction, resolution with mixtures of resolving agents, resolution with a derivative of the target compound, enantioselective chromatography, resolution by formation of covalent diastereomers, resolution by substrate selective reaction, kinetic resolution without enzymes, kinetic resolution by enzyme catalysis, hydrolytic and redox enzymes, kinetic and thermodynamic control, resolutions combined with 2nd order asymmetric transformations, enrichment of partially resolved mixtures, role of the solvent and methods of optimization in the separation of diastereoisomers, non-linear effects and selected examples of resolution on an industrial scale).  相似文献   

2.
为调查60岁以上老年人体内微量元素及钙、镁的含量,采用原子吸收光谱法对西安市60岁以上的老年人末梢血中的铜、锌、铁、镁、钙的含量进行了测定,观察了5元素的缺乏率及随年龄的增长5元素的缺乏情况.结果表明,60岁以上老年人,元素过量的情况鲜见;铜、锌、铁、镁、钙的缺乏率分别为37.87%0,11.76%,21.51%,2....  相似文献   

3.
“中药微量元素数据”分为植物药、动物药、生物甲壳药、矿物药和中成药刊出,其中又细分为解表药、泻下药、清热药、利水渗湿药、祛风湿药、温里祛寒药、芳香化湿药、理气药、理血药、补养药、固涩药、化痰止咳药、消导药、熄风镇痛药、养心安神药、芳香开窍药、外用药、驱虫药、各类中药煎煮液。检测的中药747种,共6780味。每种药包括药名、学名、科属、部位、产地、元素含量、分析方法和文献来源等8个内容。以表格形式表示。每味药物最多测定38种元素,最少测定4种元素,平均测定17种元素,共展示出的元素数据约12万个。每一个数据含义非常深刻,如序号为113的黄芩,共测定河北、山西、辽宁、黑龙江、山东、云南、四川、河南、吉林、陕西、甘肃、内蒙古、江苏等50个不同产地黄芩中的20种元素。又如序号为114的猕猴桃,共测定其中花、果、叶、枝、茎、根、皮、汁等8个不同部位中的23种元素。从元素的角度去研究中药不同产地、不同部位的药用功效,很有科研价值和实用意义。还可以用模式识别法去研究微量元素与中药的解表、清热、理气、理血等药性的关系,指导合理用药和配伍,深入研究中药与元素数据的关系,可以发现其中许多意想不到的科学规律。“数据”所参考的1036条文献,全是公开发表的论文和专著,是中国科研人员使用34种先进的分析测试方法所得的分析测试数据,是研究课题的“数据”,有高度的可靠性。对中药进行“解剖”测试,不但测定其“全身”中的元素,还测定其不同“器官”中的元素含量,如人参,既测定全参,又测定人参子、人参叶、人参皮、人参花、人参芦、人参茎、人参果、人参须等8个不同部位的元素含量,用元素功能指导临床用药很有帮助,甚至有些可用替代药,而且用中药治疗的阴虚、阳虚、气虚、阴阳两虚与中药中的元素的种类和含量息息相关。中医药不再是验方,是科学“数据”方。  相似文献   

4.
We have studied the proteins of the pollen and ovules of the cotton plant. No differences were observed in the electrophoregrams of the proteins from Gossypium hirsutum L. and from G. barbadense L. In the spectrum of the pollen proteins, the main components quantitatively were polypeptides with molecular masses of 34, 44, 47, and 52 kDa. The species G. raimondii Ulbr. differed considerably, with the main polypeptides quantitatively having molecular masses of 27, 36, 46, and 58 kDa. In representatives of genomic group C, interspecies differences were observed in the protein spectra of the pollen. No appreciable differences were observed spectrally in the proteins of the cottonplant ovules.Biolog Scientific Production Combine, Academy of Sciences of the Republic of Uzbekistan, Republic of Uzbekistan, Institute of Genetics, Academy of Sciences of the Republic of Uzbekistan, Republic of Uzbekistan, Tashkent ul. F. Khodzhaeva, 28. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 454–456, May–June, 1995. Original article submitted September 13, 1994.  相似文献   

5.
78例正常妊娠妇女和40例妊高征患者血清中铁、锌、铜、锰、硒、铬、钴和镍的含量与健康未孕妇女比较,正常妊娠妇女和妊高征患者均是铜和锰的含量升高,铁、锌、硒、铬、钴和镍含量降低;妊高征患者与正常妊娠妇女比较,则是铁、铜和锰的含量升高,锌、硒、铬、钴和镍的含量降低。  相似文献   

6.
“中药微量元素数据”分为植物药、动物药、生物甲壳药、矿物药和中成药刊出,其中又细分为解表药、泻下药、清热药、利水渗湿药、祛风湿药、温里祛寒药、芳香化湿药、理气药、理血药、补养药、固涩药、化痰止咳药、消导药、熄风镇痛药、养心安神药、芳香开窍药、外用药、驱虫药、各类中药煎煮液.检测的中药747种,共6 780味.每种药包括药名、学名、科属、部位、产地、元素含量、分析方法和文献来源等8个内容.以表格形式表示.每味药物最多测定38种元素,最少测定4种元素,平均测定17种元素,共展示出的元素数据约12万个.每一个数据含义非常深刻,如序号为113的黄芩,共测定河北、山西、辽宁、黑龙江、山东、云南、四川、河南、吉林、陕西、甘肃、内蒙古、江苏等50个不同产地黄芩中的20种元素.又如序号为114的猕猴桃,共测定其中花、果、叶、枝、茎、根、皮、汁等8个不同部位中的23种元素.从元素的角度去研究中药不同产地、不同部位的药用功效,很有科研价值和实用意义.还可以用模式识别法去研究微量元素与中药的解表、清热、理气、理血等药性的关系,指导合理用药和配伍,深入研究中药与元素数据的关系,可以发现其中许多意想不到的科学规律.“数据”所参考的1 036条文献,全是公开发表的论文和专著,是中国科研人员使用34种先进的分析测试方法所得的分析测试数据,是研究课题的“数据”,有高度的可靠性.对中药进行“解剖”测试,不但测定其“全身”中的元素,还测定其不同“器官”中的元素含量,如人参,既测定全参,又测定人参子、人参叶、人参皮、人参花、人参芦、人参茎、人参果、人参须等8个不同部位的元素含量,用元素功能指导临床用药很有帮助,甚至有些可用替代药,而且用中药治疗的阴虚、阳虚、气虚、阴阳两虚与中药中的元素的种类和含量息息相关.中医药不再是验方,是科学“数据”方.  相似文献   

7.
“中药微量元素数据”分为植物药、动物药、生物甲壳药、矿物药和中成药刊出,其中又细分为解表药、泻下药、清热药、利水渗湿药、祛风湿药、温里祛寒药、芳香化湿药、理气药、理血药、补养药、固涩药、化痰止咳药、消导药、熄风镇痛药、养心安神药、芳香开窍药、外用药、驱虫药、各类中药煎煮液。检测的中药747种,共6780味。每种药包括药名、学名、科属、部位、产地、元素含量、分析方法和文献来源等8个内容。以表格形式表示。每味药物最多测定38种元素,最少测定4种元素,平均测定17种元素,共展示出的元素数据约12万个。每一个数据含义非常深刻,如序号为113的黄芩,共测定河北、山西、辽宁、黑龙江、山东、云南、四川、河南、吉林、陕西、甘肃、内蒙古、江苏等50个不同产地黄芩中的20种元素。又如序号为114的猕猴桃,共测定其中花、果、叶、枝、茎、根、皮、汁等8个不同部位中的23种元素。从元素的角度去研究中药不同产地、不同部位的药用功效,很有科研价值和实用意义。还可以用模式识别法去研究微量元素与中药的解表、清热、理气、理血等药性的关系,指导合理用药和配伍,深入研究中药与元素数据的关系,可以发现其中许多意想不到的科学规律。“数据”所参考的1036条文献,全是公开发表的论文和专著,是中国科研人员使用34种先进的分析测试方法所得的分析测试数据,是研究课题的“数据”,有高度的可靠性。对中药进行“解剖”测试,不但测定其“全身”中的元素,还测定其不同“器官”中的元素含量,如人参,既测定全参,又测定人参子、人参叶、人参皮、人参花、人参芦、人参茎、人参果、人参须等8个不同部位的元素含量,用元素功能指导临床用药很有帮助,甚至有些可用替代药,而且用中药治疗的阴虚、阳虚、气虚、阴阳两虚与中药中的元素的种类和含量息息相关。中医药不再是验方,是科学“数据”方。  相似文献   

8.
By mass-spectrometric methods, cholesterol and docosanoic, heneicosanoic, cicosanoic, octadecanoic, cis-octadec-9-enoic, heptadecanoic, hexadecanoic, and pentadecanoic acids have been identified in the odoriferous secretion of the pre-anal glands of the females and males of the common adder and the saw-scaled viper and in those of females of the common mamushi. It has been established that the chemical compositions of the secretions of these glands of the females of the adder, the viper, and the mamushi and of the males of the adder and of the viper are not identical.Institute of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 421–423, July–August, 1986.  相似文献   

9.
With the object of determining the best conditions of temperature to be used by the analyst for weighing to constant weight precipitates containing calcium, the authors made a detailed study of the curves of pyrolysis which they have recorded by means of the Chevenard thermobalance. The following were studied : oxalate, carbonate, oxide, precipitated sulphate and gypsum, fluoride, iodate, arsenate, molybdate, tungstate, nickel-hexanitrite, tartrate, 8-hydroxyquinolate, and picrolonate. They suggest a rapid method for the analysis of the sulphate and carbonate of calcium in gypsum, a. new gravimetric determination by electrolysis of nickel-hexanitrite of calcium-potassium, of which the structural formula has been established. Finally, they recommend, in the case of precipitation of calcium as the tartrate, weighing as carbonate rather than oxide.  相似文献   

10.
The alkaloid compositions of the roots, young shoots, and leaves of Berberis sibirica have been studied, and berberine, palmatine, columbamine, berberrubine, oxyacanthine, berbamine, 8-oxoberberine, 8-oxoberrberubine, pakistanine, and pronunciferine, and also the new base N-acetylhomoveratrylamine have been isolated. This is the first time that any of these alkaloids, except berberine, have been isolated from this plant. Andizhan State Medical Institute. Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 424–428, May–June, 1993.  相似文献   

11.
研究了脑血管疾病患者头发微量元素与疾病发生的关系。采用电感耦合高频等离子体发射光谱法定量测定脑血管疾病男性患者头发中铁、铜、钙、锰、钴、镍、锶、镁八种微量元素含量,并与健康成年男性相比,差异有显著性;女性患者头发中锌、钙、镍、钼、锶、鳄、钛七种微量元素含量与健康成年女性相比,差异有显著性。提示微量元素对维持血管正常结构、保持血管完整性、抗凝及对抗自由基有重要作用。  相似文献   

12.
The laws of the fragmentation of the metastable molecular and key fragmentary ions of mono- and dienic alcohols, acetates, aldehydes, hydrocarbons, and epoxy compounds forming components of the pheromones of the turnip, tomato, and bollworm moths and other pests of agricultural crops are discussed, and the use of the laws found in the identification of compounds of this class has been demonstrated.Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, FAX 62 70 71. Tashkent State University, FAX 46 24 72. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 455–470, July–August, 1994.  相似文献   

13.
"中药微量元素数据"分为植物药、动物药、生物甲壳药、矿物药和中成药刊出,其中又细分为解表药、泻下药、清热药、利水渗湿药、祛风湿药、温里祛寒药、芳香化湿药、理气药、理血药、补养药、固涩药、化痰止咳药、消导药、熄风镇痛药、养心安神药、芳香开窍药、外用药、驱虫药、各类中药煎煮液。检测的中药747种,共6 780味。每种药包括药名、学名、科属、部位、产地、元素含量、分析方法和文献来源等8个内容。以表格形式表示。每味药物最多测定38种元素,最少测定4种元素,平均测定17种元素,共展示出的元素数据约12万个。每一个数据含义非常深刻,如序号为113的黄芩,共测定河北、山西、辽宁、黑龙江、山东、云南、四川、河南、吉林、陕西、甘肃、内蒙古、江苏等50个不同产地黄芩中的20种元素。又如序号为114的猕猴桃,共测定其中花、果、叶、枝、茎、根、皮、汁等8个不同部位中的23种元素。从元素的角度去研究中药不同产地、不同部位的药用功效,很有科研价值和实用意义。还可以用模式识别法去研究微量元素与中药的解表、清热、理气、理血等药性的关系,指导合理用药和配伍,深入研究中药与元素数据的关系,可以发现其中许多意想不到的科学规律。"数据"所参考的1 036条文献,全是公开发表的论文和专著,是中国科研人员使用34种先进的分析测试方法所得的分析测试数据,是研究课题的"数据",有高度的可靠性。对中药进行"解剖"测试,不但测定其"全身"中的元素,还测定其不同"器官"中的元素含量,如人参,既测定全参,又测定人参子、人参叶、人参皮、人参花、人参芦、人参茎、人参果、人参须等8个不同部位的元素含量,用元素功能指导临床用药很有帮助,甚至有些可用替代药,而且用中药治疗的阴虚、阳虚、气?  相似文献   

14.
The necessity of the development of the orbital structure of vibrations of nanoparticles, clusters, and coordination polyhedra is dictated by synthesis of clusters, supermolecules, and other structures of nanoscale dispersion for which translational symmetry is absent and the crystal system is inapplicable. The composition of complicated molecules, polynuclear complexes, and clusters is described, in addition to the chemical formula, by the composition equations derived from analysis of the symmetry properties of molecular structures. This analysis enables the derivation of analytical formulas for the types of molecular orbitals of structures with arbitrary groups of symmetry. Here, we use the representation of nanoscale structures described by the orbital system as a set of concentric nested spherical orbits of atoms, orbits of faces of different order, and orbits of edges. The orbits are grouped into shells shaped as polyhedra with vertices, edges, or faces accommodating atoms with different types of packing. In such a way, the sets of molecular orbitals of all high-, intermediate-, and low-symmetry groups have been determined depending on the number of atoms in the axial, planar, and primitive orbits.  相似文献   

15.
亚胺类共价有机骨架(I-COFs)是有机单体根据席夫碱(Schiff-base)反应原理缩合形成的一类新型多孔晶体有机材料.I-COFs具有骨架密度低、比表面积大、孔隙率高、单体种类丰富、孔径尺寸可控、结构可功能化、合成方法多样和物化稳定性好等优点.近年来,I-COFs已成为材料科学领域的研究前沿,并广泛用于气体吸附、...  相似文献   

16.
Recent developments in CE and CEC of peptides   总被引:1,自引:0,他引:1  
Kasicka V 《Electrophoresis》2008,29(1):179-206
  相似文献   

17.
On the basis of the results of acid hydrolysis, chromatographic analysis of the hydrolysates, and a study of IR spectra, it has been established that the suspended particles liberated under the action of electrohydraulic shocks on heterodisperse water—plant systems consist of small fragments of the lignocarbohydrate complex of the plant tissue.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. FAX (3712) 62 73 48. Division of Wood Chemistry, Irkutsk Institute of Organic Chemistry, Siberian Division of the Russian Academy of Sciences. Institute of Solar and Terrestrial Physics, Siberian Division of the Russian Academy of Sciences, Irkutsk, FAX (395-3) 46 25 57. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 435–439, May–June, 1994.  相似文献   

18.
Adsorption capacity of ACFF in cyanide leaching liquor of gold ores was studied withcyanide leaching liquor of gold ores, containing various kinds of ions. The adsorbed leaching liquorwas analyzed by atomic emission spectroscopy and colorimetric method. The contents of variouskinds of ions in ACFF were determined with X-ray photoctron spectroscopy. ACFF not onlyadsorbed gold but also adsorbed arsenic, nickel, zinc, calcium, sulphur, bismuth, copper, iron. silverand cyanide anion. Atomic percentage of C and those of O, N, Zr, Fe increase and decreaserespectively with the increase of the layer depth, while those of Ca, Au, Ag keep constant.  相似文献   

19.
Interactions between molecules are ubiquitous and occur in our bodies, the food we eat, the air we breathe, and myriad additional contexts. Although numerous tools are available for the recognition of biomolecular interactions, such tools are often limited in their sensitivity, expensive, and difficult to modify for various uses. In contrast, the quartz crystal microbalance (QCM) has sub-nanogram detection capabilities, is label-free, is inexpensive to create, and can be readily modified with a number of diverse surface chemistries to detect and characterize diverse interactions. To maximize the versatility of the QCM, scientists need to know available methods by which QCM surfaces can be modified. Therefore, in addition to summarizing the various tools currently used for biomolecular recognition, explicating the fundamental principles of the QCM as a tool for biomolecular recognition, and comparing the QCM with other acoustic sensors, we systematically review the numerous types of surface chemistries-including hydrophobic bonds, ionic bonds, hydrogen bonds, self-assembled monolayers, plasma-polymerized films, photochemistry, and sensing ionic liquids-used to functionalize QCMs for various purposes. We also review the QCM's diverse applications, which include the detection of gaseous species, detection of carbohydrates, detection of nucleic acids, detection of non-enzymatic proteins, characterization of enzymatic activity, detection of antigens and antibodies, detection of cells, and detection of drugs. Finally, we discuss the ultimate goals of and potential barriers to the development of future QCMs.  相似文献   

20.
Fundamental features and industrial applications of the direct fluorination of polymers are reviewed. Fundamental features of the direct fluorination of a set of polymers, such as polystyrene, polyethyleneterephthalate, poly(2,6-dimethyl-1,4-phenylene oxide), PMMA, LDPE (two types), HDPE (six types), polyvinyltrimethylsilane, poly(4-methyl-pentene-1), polyimide Matrimid 5216®, polysulfones, polyetheretherketone, polycarbonatesiloxane, polysulphone-polybuthadiene block-copolymers, polypropylene, PVF, PVDF, etc. are described. Influence of composition of the fluorinating mixture (F2-He-N2-O2-HF), fluorine partial pressure, temperature and fluorination duration, on the rate of formation of the fluorinated layer and the chemical composition, density, refraction index, surface energy, gas separation properties and friction coefficient of fluorinated layer have been investigated. Processes of formation and termination of long-living and short-living radicals and grafting of acrylonitrile to fluorinated polymers have been studied. Industrial applications of the direct fluorination to enhance the commercial properties of polymeric goods, such as separation factor of polymeric membranes for gas separation, barrier properties of polymer vessels, pipes and packagings, adhesion, printability, wetting and transparency in visible and IR are reviewed.  相似文献   

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