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1 INTRODUCTION Quantitative structure-activity relationship (QSAR) is one of the necessary methods to evaluate the ha- zards of organic chemicals. QSAR equation could be employed to forecast the biological activity of un- known compounds, which is significant for initial screening and evaluation of toxic compounds[1]. Aro- matic compounds are toxic organic compounds with relatively low water solubility, and their structure- activity relationship has been investigated with AM1 method[2]… 相似文献
143.
A novel coordination polymer of {[Co(4,4′-bipy)(ambdc)(H2O)2](4,4′-bipy)(DMF)}n has been synthesized using 5-aminoisophthalic acid
(H2ambdc), 4,4′-bipyridine(4,4′-bipy) and metal salts. The ambdc ligand in title compound has a μ2-monodentate coordination mode and the structure of the title compound is a two-dimensional network. CCDC: 279054. 相似文献
144.
Calcium alginate fibers have a novel gel‐forming capability in that, upon the ion exchange between sodium ions in the contact solution and calcium ions in the fiber, the fiber slowly transforms into a fibrous gel. This paper reviews the principles of the gel‐forming process for alginate fibers and analyzed the gelling behavior of various types of alginate fibers. The absorption characteristics of alginate wound dressings were analyzed and it was found that alginate wound dressings absorb a large quantity of liquid into the fiber structure, in addition to those held between the fibers in the textile structure. This gives rise to the unique gel blocking properties of alginate wound dressings. In addition, alginate wound dressings also have novel hemostatic and antimicrobial properties as well as the ability to promote wound healing. They are now widely used in the management of highly exuding wounds such as leg ulcers, pressure sores, and surgical wounds. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
145.
YingCAI JianYiWU NaWANG XiaoFengSUN XianFuLIN 《中国化学快报》2004,15(5):594-596
Michael addition reactions of uracil to acrylates were catalyzed by an alkaline protease from Bacillus subtilis in dimethyl sulfoxide at 55℃ for 72h. The adducts were determined by TLC, IR and ^1 H NMR. 相似文献
146.
In this paper, we obtain the uniqueness of the 2D MHD equations, which fills the gap of recent work by Chemin et al. (2015). 相似文献
147.
In this paper, we study the well-posedness results for the magnetic type Zakharov system. Such system describes the pondermotive force and magnetic field generation effects resulting from the nonlinear interaction between plasma-wave and particles. By using energy methods together with commutator estimate, we first derive a priori estimates for a regularized system. Then by approximation arguments, we obtain local existence results as well as global existence for small initial data. 相似文献
148.
构建了系列球形中空结构的纳米线(NW),采用分子动力学(MD)对每个模型300个不同初始态的样本开展拉伸形变模拟。并利用基于密度的噪声应用空间聚类(density-based spatial clustering of applications with noise,DBSCAN)机器学习算法,获得了初始滑移面的位置。基于大数据统计,分析了初始滑移位置分布以及断裂位置分布两者之间的相关性。研究结果表明:当内部中空半径较小时,断裂位置分布形成于塑性形变阶段,初始滑移分布与断裂位置分布之间无显著的相关性;但是对于脆性特征明显的大中空半径的NW,高能内表面诱导产生的滑移面迅速积累,产生颈缩并导致最终的断裂。因此当内部中空结构达到一定尺寸时初始滑移位置的分布与最终断裂位置的分布之间有明确的因果关系。 相似文献
149.
应用纳米磁性球电化学检测特定序列DNA 总被引:17,自引:0,他引:17
采用分散聚合法制备纳米磁性羧基球,利用化学偶联法将末端修饰氨基的寡聚核苷酸固定在纳米磁性球表面,制成新型核酸探针,该探针可特异性结合目标单链寡聚核苷酸.在磁场作用下,将纳米磁珠与本体溶液分离并富集在电极表面,以中性红为嵌合指示剂,用示差脉冲伏安法测定杂交结果.经过条件优化,本法测定DNA的浓度线性范围为1.0×10-6~5.0×10-9mol/L,检出限为8.6×10-10mol/L. 相似文献
150.
Fractal theory has been proved effective to characterize the complex pore structure. In this article, the fractal method is utilized to study the structure property of fibrous assemblies. The box dimension parameter is applied to characterize the pore structure of fibrous assemblies by analyzing the electronic scanning microscope images of the fibrous assemblies. Furthermore, a fractal model for predicting effective heat conductivity is established. Experiment is conducted to verify the model, and good agreement is found between the experimental and theoretical results. The fractal model is also compared with the previous models for predicating heat conductivity, and the former is proved to be more accurate. 相似文献