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101.
用壳聚糖(CTS)分别与硝酸亚铈,硝酸锆,硫酸镉和硝酸铅在酸性介质中反应,制备了壳聚糖-Ce(Ⅲ)、壳聚糖-Zr(Ⅳ)、壳聚糖-CA(Ⅱ)、壳聚糖-Pb(Ⅱ)四种壳聚糖-重金属离子配合物(用通式M-CTS表示).用红外光谱(IR)、X-ray衍射(XRD)和X射线光电子能谱(XPS)等光谱分析手段对M-CTS进行了结构表征.结果表明:在壳聚糖-Cd(Ⅱ)配合物中的配位原子是壳聚糖-NH2上的N原子,而在壳聚糖-Ce(Ⅲ)、壳聚糖-Zr(Ⅳ)、壳聚糖-Pb(Ⅱ)配合物中不仅壳聚糖-NH2上的N原子参与了配位,同时OH上的O原子也参与了配位.说明不同的重金属离子与壳聚糖之间形成配位键的配位原子是不完全相同的. 相似文献
102.
二茂铁基苯基甲醇与三氟化硼-乙醚溶液在二氯甲烷中作用,形成相应的二茂铁苯基甲基碳正离子,无需从反应混合物中分离出来,该离子便可与乙醇胺作用得到N-(苯基, 二茂铁基)甲基-β-羟乙胺(FcY),用该氨基醇分别与氯化镍,氯化铜,氯化锌,氯化镉,氯化汞反应,制备了氨基醇-镍(Ⅱ)、 氨基醇-铜(Ⅱ)、 氨基醇-锌(Ⅱ)、 氨基醇-镉(Ⅱ)、 氨基醇-汞(Ⅱ)五种二茂铁基氨基醇-重金属配合物(用通式M-FcY表示)。 用Nexus670FTIR红外光谱仪对二茂铁基氨基醇和五种配合物在4 000~400 cm-1范围内测定傅里叶变换红外光谱,对各M-FcY的FTIR主要吸收峰做了经验归属,并将各M-FcY的特征吸收峰与FcY的相应吸收峰作对比分析,结果表明:配合物中—OH , —NH—键的吸收峰位置均向低波数方向移动;C—O, C—N键吸收峰位置向高波数方向移动。说明二茂铁基氨基醇中的氨基、羟基与重金属离子之间形成了配位键。 相似文献
103.
Poisson's ratio in viscoelastic materials is a function of time. However, recently developed waterhammer models of viscoelastic pipes consider it constant. This simplifying assumption avoids cumbersome calculations of double convolution integrals which appear if Poisson's ratio is time-dependent. The present research develops a mathematical model taking the time dependency of Poisson's ratio into account for linear viscoelastic pipes. Poisson's ratio is written in terms of relaxation function and bulk modulus which is assumed to be constant. The relaxation function is obtained from creep function given as the viscoelastic property data of pipe material. The results obtained from the present waterhammer model are compared with the experimental data for two different flow rates. The comparison reveals that with the application of the time-dependent Poisson's ratio and unsteady friction, the viscoelastic data of mechanical tests can directly be used for waterhammer analysis with less need for the calibration of the flow configuration. It was also shown that the creep curve calibrated based on the present model is closer to the actual creep curve than that calibrated based on previous models. 相似文献
104.
Thomas W. Reiland 《Numerical Functional Analysis & Optimization》2013,34(3-4):301-323
We define order Lipschitz mappings from a Banach space to an order complete vector lattice and present a nonsmooth analysis for such functions. In particular, we establish properties of a generalized directional derivative and gradient and derive results concerning a calculus of generalized gradients (i.e., calculation of the generalized gradient of f when f = f1 + f2, f = f · 2, etc.). We show the relevance of the above analysis to nondifferentiaile programming by deriving optimality conditions for problems of the form min f(x) subject to x [euro] S. For S arbitrary we state the results in terms of cones of displacement of the feasible region at the optimal point; when S ={x ? A|g(x) ? B}, we obtain Kuhn-Tucker type results. 相似文献
105.
Based on the low-order conforming finite element subspace (Vh, Mh) such as the P1-P0 triangle element or the Q1-P0 quadrilateral element, the locally stabilized finite element method for the Stokes problem with nonlinear slip boundary conditions is investigated in this paper. For this class of nonlinear slip boundary conditions including the subdifferential property, the weak variational formulation associated with the Stokes problem is an variational inequality. Since (Vh, Mh) does not satisfy the discrete inf-sup conditions, a macroelement condition is introduced for constructing the locally stabilized formulation such that the stability of (Vh, Mh) is established. Under these conditions, we obtain the H1 and L2 error estimates for the numerical solutions. 相似文献
106.
《复变函数与椭圆型方程》2012,57(2):109-121
We study the asymptotic behavior of semigroups generated by holomorphic mappings by using an infinitesimal version of the boundary Schwarz-Wolff Lemma. In particular, the best rate of exponential convergence is obtained. In addition, we establish a geometrical version of the implicit function theorem. 相似文献
107.
This paper presents the concept of a Dielectric-lined Multiwave Cerenkov Generator(DMWCG) producing high power millimeter waves, which is investigated with a two and one half dimensional(
) electromagnetic relativistic Particle-in-Cell(PIC) simulation code. It is showed that the DMWCG can operate in a lower diode-voltage regime with much higher radiation efficiency as compared with the usual Multiwave Cerenkov Generator(MWCG). The simulation work indicates both the downshift of the wave frequency in the presence of the dielectric liner and the existence of the optima for the permittivity of the liner as well as for the magnitude of the guiding magnetic field. The required intensity of the guiding field is reduced with the introducing of the liner. The radiation is generated at the dominant frequency of 31.5GHz. The power level of 1.5GW is achieved, with radiation efficiency up to 15%. The features of parameter dependency are presented. And reasonable explanation is put forward. In addition, the enhanced propagation of the electron beam is studied in the presence of the dielectric liner. 相似文献
108.
Box-Jenkins方法在银行业市盈率预测中的应用 总被引:5,自引:0,他引:5
试用比较先进的Box-Jenkins时间序列分析方法对上市银行市盈率的历史数据进行分析,建立银行业盈利预测的ARIMA模型对我国行业经济进行分析。 相似文献
109.
110.
本文提出了一种新的离子选择性电极分析方法,即等电位差-标准加入法。本方法已用于氟的测定。进行了理论数据验证及误差分析,标准溶液的回收率为96.6%-104.3%。本方法的影响因素少、准确度好、操作及计算简便。 相似文献