Experimental studies on affinity chromatography in an electric field.

A multicompartment electrolyzer, which has been used for preparative electrophoresis [Z. Liu, Z. Huang, J.-Y. Cong, et al., Sep. Sci. Technol. 31 (1996) 427], is applied for carrying out affinity chromatography in an alternating electric field. The effect of electric field strength on the adsorption and desorption characteristics is experimentally examined with human serum albumin and Blue Sepharose Fast Flow as a model system. It is shown that the existence of an electric field leads to a significant change in the adsorption capacity of the blue dye, which may be used for establishing a preferential adsorption to achieve a high resolution. The adsorption speed increases slightly with respect to the increase of electric field strength, while adsorption capacity in the presence of an electric field is independent of the electric field strength. Different elution behavior is observed as function of adsorption condition and a high recovery of the adsorbed protein is obtained when the adsorption is carried out in the presence of an electric field.     

Multistimuli‐responsive hyperbranched poly(ether amine)s

Multistimuli‐responsive hyperbranched poly(ether amine)s (hPEAs) were successfully synthesized through nucleophilic addition/ring‐opening reaction of commercial diglycidyl ether and amine via one‐pot synthesis. In aqueous solution, these hPEAs exhibited very sharp response to temperature, pH, and ionic strength, with well‐tunable cloud point (CP). Through changing the poly(ethylene oxide) (PEO) chain content of hPEAs, pH, and ionic strength, the CP could be adjustable from 35 to 100 °C, and increased with the increasing of PEO content, the decreasing of pH and ionic strength. The CP of hPEAs aqueous solution presents a linear relationship to the PEO content in pH range from 6.6 to 8.0. Dynamic light scattering (DLS) investigation indicated that these hPEAs dispersed in aqueous solution to form the stable nanomicelles, whose aggregation can be controlled by temperature, pH, and ionic strength. Moreover, the obtained hPEAs contain reactive amino groups in periphery and hydroxyl groups inside, which can be further functionalized. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4252–4261, 2010     

为EMI敏感和高速SERDES系统供电

本文为EMI敏感和高速的SERDES系统供电提供了一种新的参考方案,即采用一个新的DC-DC微型模块,这一方案像线性稳压器一样简单,同时具备更多优越性。     

The Analysis of the Parameters and the Functions of Rectangular Waveguide E-plane Filter

In this paper, to analyze the discontinuity structure of E-plane metal insert by mode matching method, and metal insert thickness and resonator length impact on filter design. This work was supported by the Natural Science Foundation of Jiangsu Province of China under Grant No. BK2008357.     

Singularly Perturbed Switching Diffusions: Rapid Switchings and Fast Diffusions

Motivated by many problems in optimization and control, this paper is concerned with singularly perturbed systems involving both diffusions and pure jump processes. Two models are treated. In the first model, the jump process changes very rapidly by comparison with the diffusion processes. In the second model, the diffusions change rapidly in comparison with the jump process. Asymptotic expansions are developed for the transition density vectors via a constructive method; justification of the asymptotic expansions and analysis of the remainders are provided.     

Collectivity of plasmon excitations in small sodium clusters with planar structure

The collectivity of the electronic motion in small sodium clusters with planar structure is studied by the time-dependent density functional theory (TDDFT). The formation and development of collective resonances in the absorption spectra were obtained as the function of the size and shape of the plane. We find the symmetry plays an important role in the collective excitation. Resonance peaks increase with the reduction of the symmetries and, on the contrary, resonance peaks decrease with the increase of the symmetries. In the planar cluster, there are two main excitation modes: the higher-energy mode and the competitive mode, which is due to the coupling and competition of the quasi-lower-energy effect and the quasi-higher-energy effect. With the increase of the interatomic distance, peaks of the absorption spectra are all red-shifted and the evolutionary trend is also discussed.     

Measurement and Calculation of the Absolute Thermoelectric Power of Rhodium and Iridium

The thermoelectric power of Rh and Ir was redetermined between 100 K and 1400 K. It varies almost linearly from +1.7 μV K⁻¹ to −3.8 μV K⁻¹ for Rh and from +1.5 μV K⁻¹ to −2.2 μV K⁻¹ for Ir. The diffusive part of the thermopower could be calculated from the density of states. It is approximately equal to the temperature dependence of the electrochemical potential of the electrons divided by the electronic charge. This is attributed to the approximate establishment of local equilibrium between electrons and lattice atoms above 400 K—a condition not fulfilled in the phonon-drag regime below 300 K.     

Stochastic Generalized Method of Moments

The generalized method of moments (GMM) is a very popular estimation and inference procedure based on moment conditions. When likelihood-based methods are difficult to implement, one can often derive various moment conditions and construct the GMM objective function. However, minimization of the objective function in the GMM may be challenging, especially over a large parameter space. Due to the special structure of the GMM, we propose a new sampling-based algorithm, the stochastic GMM sampler, which replaces the multivariate minimization problem by a series of conditional sampling procedures. We develop the theoretical properties of the proposed iterative Monte Carlo method, and demonstrate its superior performance over other GMM estimation procedures in simulation studies. As an illustration, we apply the stochastic GMM sampler to a Medfly life longevity study. Supplemental materials for the article are available online.     

接入型服务资源配置研究

从电信业务分类出发,提出了自己的分类方法,并基于此方法详细论述了接入型服务的定义和资源配置的过程,提出了接入型服务与资源的关系模型,也具体阐述了笔者对接入方式和资源覆盖的一些思考和观点.