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101.
In this paper, we establish a the LaSalle's theorem for stochastic differential equation based on Li's work, and give a more general Lyapunov function which it is more easy to apply. Our work has partly generalized Mao's work.  相似文献   
102.
A novel strategy for efficient immobilization of electroactive Thionine(Th)on the gold(Au)electrode surface based on calcium carbonate-gold nanoparticles(CaCO3-AuNPs)inorganic hybrid composite was proposed and conducted by the strong electrostatic interaction between positively charged Th and negatively charged CaCO3-AuNPs composite.The hybrid composite was obtained by the adsorption of AuNPs onto the surface of CaCO3 microspheres through electrostatic interaction.Due to the microporous architecture,large s...  相似文献   
103.
In this paper, a composite explicit nonlinear dispersion relation is presented with reference to Stokes 2nd order dispersion relation and the empirical relation of Hedges. The explicit dispersion relation has such advantages that it can smoothly match the Stokes relation in deep and intermediate water and Hedgs's relation in shallow water. As an explicit formula, it separates the nonlinear term from the linear dispersion relation. Therefore it is convenient to obtain the numerical solution of nonlinear dispersion relation. The present formula is combined with the modified mild-slope equation including nonlinear effect to make a Refraction-Diffraction (RDF) model for wave propagating in shallow water. This nonlinear model is verified over a complicated topography with two submerged elliptical shoals resting on a slope beach. The computation results compared with those obtained from linear model show that at present the nonlinear RDF model can predict the nonlinear characteristics and the combined refracti  相似文献   
104.
IntroductionSalicylaldoxime can be used in chemically modi-fied glassy-carbon electrodes,and applied to the deter-mination of metals in water.It shows a very high recov-ery[1,2].Direct design of solid-state structures that en-compass frameworks such as grids,ladders,helicesand channels of a desired architecture is central to crys-tal engineering science[3,4].Each of the oxidationstates of copper displays a different stereochemistry,ofwhich Cu(Ⅱ)is the most representative example foritsd9elec…  相似文献   
105.
建立了离子交换色谱一直接电导法同时测定土壤中矮壮素和缩节胺残留的分析方法。样品经磨碎超声提取后,用固相萃取(SPE)柱祛除蛋白质,过0.22μm过滤膜,进样检测。考察了不同的阳离子色谱柱SH-CC-1,SH-CC-2,SH—CC_3及其不同的淋洗液对矮壮素、缩节胺的保留时间和分离度的影响。确定了最佳色谱条件:SH—CC-3阳离子色谱柱;直接电导检测;淋洗液选用3.0mmol/L甲烷磺酸,流速为1.0mL/min;柱温:40℃;进样量:100μL。在此条件下,矮壮素及缩节胺在0.20-20.0mg/地范围内,线性相关系数,均大于0.999,矮壮素和缩节胺的检出限(S/N=3)分别为0.070,0.073mg/kg,加标回收率分别为86.0%-93.8%,84.9%~93.2%,测定结果的相对标准偏差小于4.2%。方法选择性好,灵敏度高,抗干扰能力强,适用于检测土壤中矮壮素和缩节胺。  相似文献   
106.
Cucurbit[6]uril (Q6, Figure 1) is a macrocyclic ligand with interesting complexing properties. In contrast to other macrocyclic ligands, such as crown ethers, cryptands or calixarenes, this ligand has a rigid structure offering a hollow core of about 5.5 …  相似文献   
107.
采用阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)为模板剂、以ZSM-5为晶种,在水热晶化条件下合成了同时具有微孔和介孔的MCM-41/ZSM-5复合分子筛;并考察了陈化温度、陈化时间、晶化时间及模板剂用量等条件对合成复合分子筛的影响.通过X射线衍射、扫描电镜、高分辨率透射电镜、红外光谱及N2静态吸附法等手段对合成样...  相似文献   
108.
IntroductionMetal dialkyl dithiophosphates( dtp) and theirderivatives have been extensively employed both asantioxidantand antiwear additives in rubber and aslubricating oils[1,2 ] . The ligands or the metal inthese complexes can be varied according to people′sdesire and in an easily controlled manner to facili-tate the individual application,thus providing easyaccess to the understanding of details on DNA-bonding and its cleavage[3—5] .Bis( dialkyl dithiophosphate) disulfides arehighly eff…  相似文献   
109.
In this article, we consider that the geothermal gradient induces the surface tension gradient and the surface tension gradient induces longitudinal shear stress and fluid motion. The temperature gradient induces transfer of heat and matter. A theoretical solution of the velocity distribution of thin fluid film and the velocity of migration of oil are presented. Three experiments attest to the geothermal gradient is assuredly a driven force of the migration of oil. An experiment is mathematics simulation of migration of oil; the other two experiments are from literatures (Huang, C., Hu, L., & Kang, Q. (2005) Acta Mechanica Sinica, 37 (02), 232–237; Qiu, N. & Fang, J. (2003) Oil & Gas Geology, 24 (03), 210–214 [in Chinese].). All experiments show that under the action of an applied temperature difference the gradient of surface tension is formed. The consequence of variation of the surface tension due to a thermal gradient results in a tangential stress which, by viscous traction, causes the motion of neighboring fluid. The temperature difference and time control the migration velocity and distance. This also may effect accumulation and evolvement of oil/gas.  相似文献   
110.
采用氧弹燃烧法对海藻酸钠样品进行燃烧,用碳酸钠作为吸收液进行吸收,建立了离子色谱-抑制电导法检测海藻酸钠中阴离子的方法.实验采用SH-AC-1型离子交换色谱柱,最佳色谱条件:以3.6 mmol/L碳酸钠为淋洗液,柱温45℃,流速0.7 mL/min.在此条件下,可同时分离Cl-、SO42-离子,且色谱峰型对称,所测C1...  相似文献   
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