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1.
<正>公布号:CN104849687A;公布日:2015.08.19申请人:中国电子科技集团公司第四十一研究所摘要:本发明提出了一种基于散射参数级联的微波自动测试系统校准方法,包括以下步骤:根据具体测试应用状态,确定校准和测试所包含的全部测试通道及其各基本组成单元,并  相似文献   

2.
稀土掺杂对锂离子电池正极材料LiMn2O4结构及电性能的影响   总被引:19,自引:5,他引:19  
利用微波加热技术合成稀土掺杂基锂离子电池正极材料LiMn2-xRExO4(RE=Y,Nd,Gd,Ce),通过XRD、循环伏安及恒电漉充放电测试研究了稀土掺杂离子对合成正极材料结构及电化学性能的影响。XRD测试结果表明,合适的掺杂量可以起到扩展锂离子脱嵌通道和稳定骨架结构的作用,稀土离子的引入可以部分取代原有的三价锰离子,由于稀土离子的离子半径较三价锰离子大,因此稀土掺杂锰酸锂材料的晶胞参数比未掺杂材料大,在一定程度上扩充了锂离子迁移的三维通道,更有利于锂离子的嵌入与脱嵌;循环伏安及恒电漉充放电测试结果表明稀土掺杂有效提高了LiMn2O4材料的电化学循环可逆性及循环稳定性。  相似文献   

3.
针对高含水储层堵水、控水困难的问题,采用多重物理、化学作用,以弱交联两性离子高分子/表面活性剂协同组装成超分子凝胶堵剂体系。通过测试不同影响因素下凝胶体系的表观粘度,优化组装自修复水凝胶堵剂的最佳条件,采用流变仪测试了凝胶的流变性及剪切修复性,采用盐水配制凝胶测试了体系的稳定性,采用岩心流动实验测试了堵剂体系的封堵和控水能力,通过扫描电子显微镜分析了堵剂凝胶的成胶、堵水控水机理。研究结果表明,堵剂凝胶被剪切后粘度具有良好的自组装修复性能。同时堵剂凝胶具有良好的封堵能力、热稳定性和耐盐性。堵剂对高渗岩心封堵效果优于低渗岩心。岩心驱替时,驱替液难以完全扫过岩心的每一个流通通道。岩心见水后油流将难以取代水流通道,即难以降低生产含水。凝胶堵剂通过多重作用形成具有自修复功能的树状网络结构,以实现体系的疏水、控水功能。  相似文献   

4.
专利介绍     
水中阴离子表面活性剂的测试装置及制备方法 本发明提供一种简易测定水中阴离子表面活性剂含量的测试装置.这种测试装置由测试导管连接2个漏斗,测试导管之间串联管状流通式敏感膜电极构成测试通道,内参比电极设置于管状流通式敏感膜电极上,外参比饱和甘汞电极插在一个漏斗之中,内外参比电极通过导线与pH酸度计相连.本发明以自制石墨测试导管为基体,  相似文献   

5.
研制出一种以时间分辨荧光微球作为标记,自驱动快速检测H-FABP的荧光免疫微流体测试卡.利用激光切割法在双面胶上简便、快速地切割出所设计的微通道结构,并采用激光切割法制作出聚甲基丙烯酸甲酯(PMMA)测试卡底板及上盖.使用提拉涂膜的方法在PMMA底板表面修饰马来酸酐官能团,有效地解决了捕获抗体在PMMA表面的固定问题.使用等离子体处理测试卡上盖改善其亲水性,使液体能够在微通道内自行流动.使用此测试卡可以实现对心型脂肪酸结合蛋白(H-FABP)的快速检测,线性检测范围为0.5~ 100 ng/mL,检出限为0.1 ng/mL(S/N=3),检测时间少于10 min,批内相对标准偏差(RSD) <10%,批间RSD<15%.本方法具有灵敏度高、检测时间短、结果准确等优点,可以满足临床检测的需求,具有良好的应用前景.  相似文献   

6.
建立了用铝基体火花源原子发射光谱仪现有通道硬件测定镁合金(MB1)中锰元素含量的方法.方法线性相关系数为0.967 6,RSD为1.66%.对8个未知样品进行了测试,结果与化学分析方法所得结果一致.  相似文献   

7.
本文从信息论观点出发,将彩色照相材料作为一个客观景物信息的传输通道,其单个空间可分辨面积构成一个独立信道,照相材料是大量独立信道并联组成的扩展信道,并提出了使用复层Shannon熵计算彩色照相材料独立信道容量的方法。作者在PDS显微光密度计——电子计算机系统上发展了全套测试计算程序,并完成了中国1821型彩色红外航空负片的信道容量测试。  相似文献   

8.
李仲秋  吴增强  夏兴华 《色谱》2020,38(10):1189-1196
近年来,随着材料科学、微纳加工技术和微纳尺度物质传输理论的发展,纳通道技术得到了越来越多的研究和关注。纳通道包括生物纳通道和人工纳通道,其孔径通常为1~100 nm。在这一尺度下,通道表面与通道内物质之间的作用概率大大增强,使得纳通道表现出许多与宏观体系不同的物质传输特性,例如通道表面电荷与通道内离子之间的静电作用产生了离子选择性,通道内电化学势的不对称分布产生了离子整流特性,物质传输过程中占据通道产生了阻塞脉冲特性等。纳通道中的这些物质传输特性在传感、分离、能源等领域具有广泛应用,例如通过对纳通道进行功能化修饰可以实现门控离子传输;利用亚纳米尺度的通道可以实现单分子传感;利用通道与传输物质之间的相互作用可以实现离子、分子、纳米粒子的分离;利用纳通道的离子选择性可以在通道内实现电荷分离,将不同形式的能量(如光、热、压力、盐差等)高效转化为电能。纳通道技术是化学、材料科学、纳米技术等多学科的交叉集合,在解决生物、环境、能源等基本问题方面具有良好的前景。该文综述了近10年来与纳通道物质传输理论以及纳通道技术应用相关的前沿研究,梳理了纳通道技术的发展过程,并对其在各个领域的应用进行了总结与展望。  相似文献   

9.
介绍了一种新型的使用石蜡庚烷溶液制备纸基微流控分析装置的工艺,操作更加简单迅速,成本更加低廉。使用混合样品溶液进行测试,证明该装置可以完成对蛋白质、葡萄糖和pH值的同时检测,并可以用于定量分析。纸基微流控分析装置对样品检测的精度范围分别为:牛血清蛋白2.0×10-5~1.00×10-4mol/L,葡萄糖0.02~0.1 mol/L。并对加热处理过程中微流控通道壁的扩散现象进行了初步研究,发现加热前后通道壁厚度的变化呈线性规律。  相似文献   

10.
水通道蛋白是对水分子具有高选择性和渗透性的跨膜蛋白。仿生水通道是由各种无机或有机材料,如碳纳米材料、有机化合物以及肽等分别自组装而成,旨在模仿天然水通道蛋白的结构和功能。本文介绍了水通道蛋白的种类、结构及其特异性透水机理,在此基础上分别对以碳纳米材料、有机及肽孔的仿生水通道的研究进展进行了综述。重点阐述了三类仿生水通道的材料特性及其对仿生水通道结构和功能的影响。最后针对现有仿生水通道的不足,提出了开发新型仿生水通道面临的挑战,并展望了仿生水通道的发展前景。  相似文献   

11.
A simple relationship is reported between vibrational frequencies, bond lengths, and reduced masses for many families of stable, ground state diatomics: the frequency is proportional to the reciprocal of the product of the bond length and the square root of the reduced mass. This is demonstrated with each of the following related families: the alkali metal diatomics, the group 15 diatomics, the group 16 diatomics, the halogen diatomics, the alkali metal hydrides, the alkaline earth oxides, the group 14 oxides and their sulfides, the diatomics of carbon, of silicon and of germanium with group 16 elements, the hydrogen halides, the halides of lithium, of sodium, of potassium, of rubidium and of cesium, the chlorides of the alkali metals and of silver, and the polyatomic hydrides of groups 14 and 15. Although correlation coefficients of 0.99 or greater in each of the 21 families examined demonstrate the validity of the correlation, the deviations found are significantly larger than can be attributed to experimental uncertainties.  相似文献   

12.
《Arabian Journal of Chemistry》2020,13(12):8920-8934
Pharmaceutical and clinicians researchers are looking for novel drug carriers to maintain the drug level in the body in low and effective dose. Thus, the present research concerned with studying the behavior of some natural biomass materials, namely microcrystalline cellulose, MCC, nanocrystalline cellulose, NCC, nanomethylcellulose, MC, and carboxymethyl cellulose, CMC, as a drug carrier materials for the Gentamicin sulphate, GM, by following up their rate of releasing the loaded drug with the time. Knowing of the initial rate of the releasing to each one and the sustaining rate along the period of the treatment, helps in choosing the best carrier for the drug that matches the patients requirements either whom are in need for a rapid dose (high level) of the drug followed by slow (low level) dose or those in need to start with the low level of the drug followed by high level of the drug. We chose MCC, NCC, MC and CMC, as natural, nontoxic biodegradable and renewable biomass materials, beside their low cost, to carry out this study. The results of the drug release, which measured by UV spectra, showed that the MCC, NCC, MC and CMC loaded with 0.025 g of the GM drug released 27.2%, 42.1%, 29.7%, 28.5% of the drug, respectively, along 10 days. All of them achieved the slow of the drug release but their behavior were different, where MCC, NCC and CMC started with low release then increased, and inversely, MC gave high rate of drug release and then decreased. The cause of this behavior was concerned to the adsorbing of the drug particles on the surface of the biomass materials or absorbing of the drug particles into the pores of the biomass materials. This was indicated by the study of their morphological image using the SEM, as well as indicating the presence of the functional group using the FT-IR study. The XRD, EDX and Agar Diffusion Assay, i.e. antimicrobial activity, against Staphylococcus aureus, Escherichia Coli, Pseudomonas aeruginosa and Bacillus subtilis were carried out to make help in choosing of the best carrier convenient to the case of the illness requirement.  相似文献   

13.
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.  相似文献   

14.
The surface lipids of the coat and the lipids of the kernel of the seeds of a wild form of the medium-fibered cotton plantGossypium mexicanum var.nervosum have been studied in comparison with cultured species. Using the methods of CC, TLC, and GLC, and UV and mass spectrometry, in the cuticular lipids ofG. mexicanum three classes of neutral lipids have been detected, and in the kernel lipids 10 classes of neutral lipids, 2 classes of glycolipids, and 7 classes of phospholipids. The structures of the epoxyacyl-, hydroxyacyl-, and diacylglycerols of the kernel have been established. The greatest differences between the seeds of the wild form of the cotton plant and the cultured species are the greater weight of the seed coat, the presence in it of a considerable amount of the 18:1 and of medium-molecular-weight fatty acids, and a higher level in the kernel of gossypol pigments, polar lipids, and acylglycerols containing the 18:2 acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 57–62, January–February, 1987.  相似文献   

15.
Brazil is one of the largest producers of fruits cropping 40 million tons per year. In agro-food processing, approximately 50 % of raw material is discarded generating large amounts of by-products. The lack of information on the nutritional quality of agroindustrial by-products precludes their potential use in the manufacture of food products accessible to all. In this context, the objective of this work was to investigate the nutritional quality of by-products of the industrial processing of fruits. Samples of bagasse, peel and seeds of several fruits (banana, camu camu, coconut, cupuaçu, guava, jackfruit, mango, orange, papaya, pineapple, and soursop) were analysed by neutron activation analysis for the determination of Br, Ca, Co, Cr, Cs, Fe, K, La, Na, Rb, Sc and Zn. In general, higher levels of minerals were found in the by-products rather than in the pulps of fruits. This indicates that the use of the by-products should be encouraged, thereby reducing the economic and environmental impact of waste generated by agroindustrial processing.  相似文献   

16.
A possibility of the analytical application of a low-melting extractant, antipyrinium acetylsalicylate, to the extraction of a number of ions from acid aqueous solutions is studied. The distribution of Al, As, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, Sn, Ti, V, and Zn ions between the aqueous solution and an organic extractant is studied by atomic emission spectrometry. The efficiency of ion extraction from acid solutions with a low-melting flux of antipyrinium acetylsalicylate is calculated. It is shown that single extraction with an extractant flux ensures the efficient extraction of Fe, Mo, Sn, and Ti from the water phase of the analyzed solution to the flux. The introduction of chloride ions into the analyzed acid aqueous solution significantly increases the efficiency of the group preconcentration of ions by the ion-exchange mechanism.  相似文献   

17.
Polyolefins (POs) constitute an extremely interesting family of materials. They include large-volume materials such as polyethylene and polypropylene and specialty materials. Outstanding scientific and technology developments have led to the most aggressive, endless, always increasing, successful growth speed of any family of large-volume materials. For those of us who have lived through the entire PO adventure, from its problematic beginnings to the eventual successful developments of the last 25 years, it has been a quite unforeseeable and unexpected story not shared by the majority. The main reason for such behavior and the present situation is the inherent complexity of their catalytic systems, which are difficult to understand and manage, along with all the consequences in terms of the process versatility, the reliability and cost, the lack of product properties, and the possibility of new material creation and commercial availability. After the early commercial disappointments of the 1960s and early 1970s, the deep commitment of the industry in research and development, mostly aimed at an understanding of the catalysis and its improvement and management, created the basis for and led to the generation of new, elegant, and versatile processes and, most importantly, to the generation of new products and properties. It activated that dynamic and aggressive growth that, since the late 1970s, has characterized the entire PO market and still, at the beginning of the third millennium, is not showing any sign of decline. An attempt to provide a rational explanation for such a unique case of technological and commercial success in the history of materials has led us to the following conclusions. First, dramatic improvements in the polymer properties and the generation of new materials have been the key reasons for their commercial success and continuous market expansion. Second, the tremendous and dynamic development of new, elegant, and versatile technologies has been and is the fundamental prerequisite for the generation of that rich world of new properties and materials. Third, the strategic management of the technological background and potential for the creation of new properties and new applications has been and is the basis for the fast and successful market expansion. The key technological driving force has been the understanding and management of the catalytic system. The early generations of chromium-based and Ziegler–Natta catalysts, after a difficult beginning, have progressively accelerated in their development toward new revolutionary generations with outstanding potential in terms of the creation of new polymer properties. The most recent families of single-site catalysts, together with the still largely unexploited potential of the previous Ziegler–Natta, chromium, and vanadium catalysts, are showing the ability to guarantee the continued support and fueling of the expansion for several further decades. The development philosophy will always be more tuned toward the creation of low-cost, low-environmental-impact polymers and processes, with a minimum amount of constraints. Today, at the beginning of the new century, we see the PO future as still very bright because of the huge, unexploited potential of already existing and emerging technologies. The PO adventure continues and is still exciting like it was 50 years ago. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 396–415, 2004  相似文献   

18.
有益微量元素在人体的正常生命机能和各种新陈代谢中都发挥着重要的作用,同时有害重金属含量过高会对人体产生负面的影响。指甲是微量元素代谢的途径之一,因此分析指甲中元素的含量具有重要意义。本文首先建立了指甲中元素含量测定方法,采用微波消解法对指甲样品进行前处理,再使用ICP-MS测定V、Cr、Mn、Fe、Co、Cu、Zn、As、Se、Mo、Ag、Cd、Hg和Pb元素的含量,实验结果表明该方法的准确度和精密度良好。然后对同一地区100份不同个体的指甲进行了测定,结果表明指甲中有些元素的含量受性别影响,也跟环境和饮食有关。  相似文献   

19.
Abstract

Copper(II) complexes of various optically active di- and tripeptides have been studied with the aid of optical rotatory dispersion (ORD) and circular dichroism (CD) techniques. The magnitudes of the molecular rotations related to the d-d transitions of the complexes fall into three different ranges, depending on the positions of asymmetric carbon atoms of the ligands. The molecular rotations of GAG and GLG complexes are greater than those of GGA, GGL, and GGV complexes, which are again greater than those of AGG, LGG, and VGG complexes (G, A, L, and V are glycine, alanine, leucine, and valine residues, respectively, in the tripeptides investigated, the N-terminal residue being the first residue in each abbreviation). The structures of these complexes, deduced from their potentiometric equilibrium curves and from the known crystal structure of the copper(II)-triglycine complex, show that the asymmetric carbon atoms of the second and third amino acid residues (counting from the N-terminal amino acid residue) are in the plane composed of the central metal ion, the nitrogen atoms of the amino and peptide groups, and the oxygen atom of the carboxylate group. The magnitude of the Cotton effect increases with the planarity of the chelate rings which include the asymmetric carbon atom and the metal ion, and with increasing strength of the coordinate bonds that form these chelate rings. Further support for this interpretation is found in the CD spectra of the copper(II) and nickel(II) complexes of AGG, GAG, GGA, and AAA. Analysis of the CD spectra of LL and DL alanylalanine complexes also demonstrate the influence of planarity and coordinate bond strength on the magnitude of the Cotton effect. Schiff base formation of aldehydes and ketones with dialanines causes fundamental changes in the geometries of the copper(II) complexes and reverses the relative contributions of the chelate rings to the total CD absorption intensities of the complexes.  相似文献   

20.
The study of asymmetric lipid bilayers is of a crucial importance due to the great number of biological process in which they are involved such as exocytosis, intracellular fusion processes, phospholipid-protein interactions, and signal transduction pathway. In addition, the loss of this asymmetry is a hallmark of the early stages of apoptosis. In this regard, a model of an asymmetric lipid bilayer composed of DPPC and DPPS was simulated by molecular dynamics simulation. Thus, the asymmetric membrane was modeled by 264 lipids, of which 48 corresponded to DPPS- randomly distributed in the same leaflet with 96 DPPC. In the other leaflet, 120 DPPC were placed without DPPS-. Due to the presence of a net charge of -1 for the DPPS- in physiological conditions, 48 Na+ were introduced into the system to balance the charge. To ascertain whether the presence of the DPPS- in only one of the two leaflets perturbs the properties of the DPPC in the other leaflet composed only of DPPC, different properties were studied, such as the atomic density of the different components across the membrane, the electrostatic potential across the membrane, the translational diffusion of DPPC and DPPS, the deuterium order parameters, lipid hydration, and lipid-lipid charge bridges. Thus, we obtained that certain properties such as the surface area lipid molecule, lipid head orientation, order parameter, translational diffusion coefficient, or lipid hydration of DPPC in the leaflet without DPPS remain unperturbed by the presence of DPPS in the other leaflet, compared with a DPPC bilayer. On the other hand, in the leaflet containing DPPS, some of the DPPC properties were strongly affected by the presence of DPPS such as the order parameter or electrostatic potential.  相似文献   

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