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91.
近年来,微纳分离技术由于其内在的优势而受到越来越多的关注.多孔层开管柱是一种重要的微分离柱形式,与粗内径的多孔层开管柱(>25μm)相比,窄内径的多孔层开管柱具有更高的分离效率和更低的试剂消耗量.本文综述了内径≤25μm的窄内径多孔层开管毛细管柱的制备方法、与质谱检测联用技术以及在液相色谱中的应用研究进展,对其发展前景进行了展望.  相似文献   
92.
福州市尤溪洲闽江大桥是国内首座在拱肋(圈)上不设立柱和斜撑的空腹式刚架拱桥.作为空腹式刚架拱桥受力关键部位——梁与拱的连接部位,受力及构造复杂.通过三维光弹性试验,研究该梁、拱结合部的内力传递、应力集中、局部应力分布规律,为空腹式刚架拱桥节点设计、施工提供依据.  相似文献   
93.
Diabetes, a multifunctional disease and a major cause of morbidity and mortality in the industrialized countries, strongly associates with the development and progression of atherosclerosis. One of the consequences of high level of glucose in the blood circulation is glycation of long-lived proteins, such as collagen I, the most abundant component of the extracellular matrix (ECM) in the arterial wall. Glycation is a long-lasting process that involves the reaction between a carbonyl group of the sugar and an amino group of the protein, usually a lysine residue. This reaction generates an Amadori product that may evolve in advanced glycation end products (AGEs). AGEs, as reactive molecules, can provoke cross-linking of collagen I fibrils. Since binding of low-density lipoproteins (LDLs) to the ECM of the inner layer of the arterial wall, the intima, has been implicated to be involved in the onset of the development of an atherosclerotic plaque, collagen modifications, which can affect the affinity of native and oxidized LDL for collagen I, can promote the entrapment of LDLs in the intima and accelerate the progression of atherosclerosis.In this study, open tubular capillary electrochromatography is proposed as a new microreactor to study in situ glycation of collagen I. The kinetics of glycation was first investigated in a fused silica collagen I-coated capillary. Dimethyl sulphoxide, injected as an electroosmotic flow marker, gave information about the charge of coating. Native and oxidized LDL, and selected peptide fragments from apolipoprotein B-100, the protein covering LDL particles, were injected as marker compounds to clarify the interactions between LDLs and the glycated collagen I coating. The method proposed is simple and inexpensive, since only small amounts of collagen and LDL are required. Atomic force microscopy images complemented our studies, highlighting the difference between unmodified and glycated collagen I surfaces.  相似文献   
94.
产电对微生物燃料电池参数的影响   总被引:1,自引:0,他引:1  
测试了pH值和电导率的变化规律,分析了MFC开路电压的变化情况,为改善MFC的性能提供理论依据.采用驯化培养的菌种,MFC启动时间更短;在恒温、高温和高底物浓度条件下,开路电压更高、更稳.产物在阳极液中的积累会降低开路电压.阴极液和阳极液的pH值的差值与电流正相关.阳极液的电导率会减小,而阴极液的电导率会增大;阳极液中...  相似文献   
95.
In 2000 [1], Zahran introduced the concept of regular open sets in fuzzifying topology. In 2004 [2], Sayed and Zahran, gave an example to illustrate that the statements:
  • (1)ARτAτ (Lemma 2.2 [1]); and
  • (2)(ARτBRτ)ABRτ (Theorem 2.4 [1]),
are incorrect. In the present paper we redefine this concept to make these statements correct. Furthermore, by making use of our definition of regular open sets, the concepts of almost continuity and δ-continuity are introduced and studied in fuzzifying topology.  相似文献   
96.
In this paper, we deal with one kind of two-player zero-sum linear quadratic stochastic differential game problem. We give the existence of an open loop saddle point if and only if the lower and upper values exist.  相似文献   
97.
我们根据一般化凸空间上的KKM型定理得到了截口定理,然后作为它的应用讨论了若干个择一不等式.最后,引进了一个具体的一般化凸空间并在该空间上讨论了择一不等式解的存在性问题.  相似文献   
98.
陈荣军  秦立珍  唐国春 《数学杂志》2015,35(5):1068-1074
本文研究制造商可以将工件转包给承包商加工的排序模型,承包商仅有一台机器,转包费用由分配给转包工件的不同时间段费用确定.本文分别研究制造商有一台单机及两台自由作业机器环境情形,需要确定被转包工件集及全部工件的加工顺序,使得工件最大完工时间与转包费用和最小.本文利用归约方法对制造商每个机器环境,证明问题NP困难性,并提出动态规划算法.  相似文献   
99.
An angular‐shaped naphthalene tetracarboxylic diimide (NDI) was designed and synthesized as a new building block for n‐type conjugated polymers to tune their energy levels. Three n‐type copolymers incorporating this angular‐shaped NDI as the acceptor moiety were obtained by Stille coupling reactions and had number average molecular weights of 18.7–73.0 kDa. All‐polymer bulk‐heterojunction solar cells made from blends of these polymers with poly(3‐hexylthiophene) gave a power conversion efficiency up to 0.32% and exhibited an open‐circuit voltage (Voc) up to 0.94 V due to their relative high‐lying lowest unoccupied molecular orbital energy levels. The high Voc of 0.94 V is higher than that of solar cells based on linear‐shaped NDI‐containing polymers (<0.6 V). The results indicate that the angular‐shaped NDI is a promising building block for constructing nonfullerene polymer acceptors for solar cells with high open‐circuit voltages. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   
100.
The stability and accuracy of radiation type non‐reflective outflow boundary conditions, as well as the standard Neumann boundary condition with zero normal derivative, have been compared for the numerical simulation of a turbulent axisymmetric plume with Reynolds number of 7700 and Prandtl number of 0.71. Comparison of the performance of the boundary conditions with respect to each other, and to the results obtained for an extended domain, shows that a one‐dimensional scheme in which advection and diffusion terms are included in the radiation equation is the optimum approach for the plume simulation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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