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高分子化学是高分子科学的三大分支领域(高分子化学、高分子物理、高分子工程)之一,它的学科领域覆盖了聚合反应研究、高分子合成及高分子改性.由于高分子化学肩负着为高分子学科提供新高分子化合物的首要任务,因此是高分子科学的基础.我国从事高分子化学研究的科研人员,约占全部从事高分子研究人员的65%,因引高分子化学研究也是我国高分子科学研究队伍的主流(见表1).我国的高分子化学研究涉及新聚合反应及新聚合方法研究、聚合反应动力学研究、功能高分子的分子设计和 相似文献
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高分子科学是蓬勃发展的高分子材料工业的理论基础,对其深刻理解、灵活运用是进行高分子工业实践的前提条件,然而当前高分子专业学生中存在对高分子科学不感兴趣或者"偏见"现象,影响了高分子科学的教学效果和后续实践,因此,开展高分子科学教学研究,对培养具备深厚高分子科学理论与应用兴趣的专门人才具有重要意义。作者阐述了为激发学生长久、自主学习兴趣进行的高分子科学第一课教学改进体会,即强调高分子材料的价值宣讲、突出高分子知识的应用特性和演义高分子科学丰富历史,结合知识性、故事性和实际性多维度教学,引导同学们走近高分子、走进高分子、爱上高分子。 相似文献
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本文评述了高分子负载金属催化剂的分类及其高分子效应,重点评述了高分子负载金属络合物催化剂的载体功能基效应,多功能协同效应,高分子场效应和高分子基体效应,对高分子分散金属催化剂的高分子效应研究也作了一定的综述。 相似文献
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生物特异性功能高分子 总被引:1,自引:0,他引:1
模仿天然生物活性高分子关键作用点的化学组成,在高分子链上接上各种官能团或化学残基,制备具有与该天然高分子相似生物活性的高分子,即生物特异性功能高分子。本文主要介绍拟肝素高分子和似粘连 蛋白高分子两种生物特异性功能高分子。 相似文献
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分别按高分子合成化学、高分子科学与生命科学的交叉研究、光电磁活性功能高分子、超分子组装与高级有序结构构筑、高分子物理与高分子物理化学、高分子加工新原理、新方法等,对高分子科学近期主要发展趋势和若干前沿方向做一综述. 相似文献
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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
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Based on 25 years of experience of the pyrolysis of several thousands of inorganic and organic substances with. reference to gravimetric analysis, studies of volumetric standards and studies of solid-state reactions, the author attempts to explain the disagreements in results obtained by users of various models of thermobalances. These differences are traced to 10 main causes: the type of apparatus, the thermocouple, the nature of the substance involved, the weight of this substance, the rate of heating, the nature of the atmosphere around the crucible, the gas flow-rate in the furnace, the nature and shape of the crucible, the sensitivity of the recorder trace, and the nature and weight of the residue. 相似文献
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A. S. Imamkhodzhaeva A. P. Ibragimov Sh. Yu. Yunuskanov 《Chemistry of Natural Compounds》1995,31(3):376-378
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
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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
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Effect of solvents on electro-spinnability of polystyrene solutions and morphological appearance of resulting electrospun polystyrene fibers 总被引:2,自引:0,他引:2
Teeradech Jarusuwannapoom Sujinda Jitjaicham Manit Nithitanakul Piyawit Koombhongse Pitt Supaphol 《European Polymer Journal》2005,41(3):409-421
The effects of solvents and their properties on electro-spinnability of the as-prepared polystyrene (PS) solutions and the morphological appearance of the as-spun PS fibers were investigated qualitatively by means of a scanning electron microscope (SEM). The eighteen solvents used were benzene, t-butylacetate, carbontetrachloride, chlorobenzene, chloroform, cyclohexane, decahydronaphthalene (decalin), 1,2-dichloroethane, dimethylformamide (DMF), 1,4-dioxane, ethylacetate, ethylbenzene, hexane, methylethylketone (MEK), nitrobenzene, tetrahydrofuran (THF), 1,2,3,4-tetrahydronaphthalene (tetralin), and toluene. The PS solutions in 1,2-dichloroethane, DMF, ethylacetate, MEK, and THF could produce fibers with high enough productivity, while the PS solutions in benzene, cyclohexane, decalin, ethylbenzene, nitrobenzene, and tetralin were not spinnable. Qualitative observation of the results obtained suggested that the important factors determining the electro-spinnability of the as-prepared PS solutions are high enough values of both the dipole moment of the solvent and the conductivity of both the solvent and the resulting solutions, high enough boiling point of the solvent, not-so-high values of both the viscosity and the surface tension of the resulting solutions. 相似文献
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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
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M. Nigmonov N. I. Koryakina V. K. Burichenko L. I. Lavrent'eva 《Chemistry of Natural Compounds》1988,24(3):338-342
The results are given of a study of the quantitative content of protein in the seeds of some pea varieties and mutants, the activity of the total inhibitor proteins, and correlations of their activity with the protein content of the seeds and the amino acid compositions of the proteinase inhibitors. Considerable differences have been found in the amounts of a number of amino acids of the protein inhibitors of parental varieties and mutants of the pea, the amounts of serine, glutamic acid, alanine, and valine correlating positively with the inhibitor activity.Institute of Plant Physiology and Biophysics, Tadzhik SSR Academy of Sciences, Dushanbe. V. I. Nikitin Institute of Chemistry, Tadzhik SSR Academy of Sciences, Dushanbe. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 399–404, May–June, 1988. 相似文献
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The aim of this investigation was to develop a basic understanding of the emulsification process by considering simple systems such as n-hexane, n-heptane, n-decane, and kerosene oil in water. The technique employed for the purpose was ultrasonification. The effect of ultrasonification time, chain length, viscosity, surface tension, oil content, and ionic strength of the media on the quality of emulsion has been studied. The emulsions were viewed through microscope to measure the number, size, and size distribution of droplets. Quantification of turbidity and viscosity was also used to characterize the emulsions. It has been found that the number and size of the droplets vary with the time of ultrasonification, contents of oils, molecular mass of the oils, and ionic strength of the media, and hence the quality of the emulsion is influenced by these parameters. The droplet size decreases, whereas the number of drops increases with the time of emulsification, approaching an optimum distribution at about 15 min of ultrasonification. Further, the increase in the molecular mass of the oil increases the size of the droplets and hence decreases the stability of the emulsion. The addition of electrolytes encourages coalescence and enhances the instability in the system. The results are in accord with the equations proposed by us. 相似文献
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翻译后修饰是蛋白质组学研究的前沿和重点,它不仅调节着蛋白质的折叠、状态、活性、定位以及蛋白质间的相互作用,也能帮助科学家更全面地了解生物体的生命过程,为疾病的预测、诊断和治疗提供更加强大的支撑和依据。翻译后修饰产物(例如磷酸化肽和糖肽)丰度很低,且存在着强烈的背景干扰,很难直接用质谱进行分析,因此迫切需要开发高效的富集材料和技术来选择性富集翻译后修饰产物。近年来,智能聚合物基材料通过外部物理、化学或生物刺激可逆地改变其结构和功能,实现对磷酸化肽和糖肽高度可控的吸附和脱附,进而衍生开发出一系列新颖的富集方法,极大地吸引研究者们的兴趣。一方面,智能聚合物基材料的响应变化包括材料疏水性的增加或减少、形状和形貌的改变、表面电荷的重新分布以及亲和配体的暴露或隐藏等特性。这些特性使得目标物和智能聚合物基材料之间的亲和力可以通过简单改变外部条件(如温度、pH值、溶剂极性和生物分子等)实现更可控和更智能的精细调节。另一方面,智能聚合物基材料为集成功能模块提供了便捷的可扩展平台,例如特定的识别组件,显著提高了目标物质的分离选择性。智能聚合物基材料在分离方面展现出巨大的潜力,这为蛋白质翻译后修饰产物的分析和研究带来了希望。围绕上述主题,该文依据Web of Science近20年来近50篇代表性文献,概述了智能聚合物基材料在磷酸化肽和糖肽分离及富集中的发展方向。 相似文献
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为排除Isoprime 100稳定性同位素比质谱仪在测定δ~(13)C和δ~(15)N过程中常见的故障,探讨分析系统检漏通不过、峰中心检测不合格、稳定性达不到要求等故障产生的原因,结合操作实际,从仪器测定前状态检查、测试过程监控、测试完毕各部件维护等方面总结归纳仪器故障的预防办法,同时提出了系统漏气、离子源损坏、机械泵损坏等故障的排除方法.通过采取以上措施,可以保证测试数据的准确性,减少仪器的故障率,延长仪器使用寿命,保障仪器及时高效地应用于教学和科学研究工作. 相似文献