Vitamin K1在水-有机溶剂中单电子还原电位的测定

ＶｉｔａｍｉｎＫ１（ＶＫ１）是一种非常重要的脂溶性维生素,其止血功能已为人们所熟悉．下图显示在生物体内ＶＫ参与的止血过程,在这个氧化还原循环过程中,ＶＫＨ２环氧化变成ＶＫＯ与Ｇｌｕ(谷氨酸蛋白)羧化而转变成Ｇｌａ(γ-羧基谷氨酸蛋白)是同时发生的,但前一?..     

HL—1M多发弹丸加料等离子体的特性

对ＨＬ－１Ｍ装置在一次放电中注入３－８粒氢弹丸的欧姆加热等离子体密度分布和扰动特征进行了研究。实验表明,器壁再循环对高密度的获得有重要的影响。在再循环较高的条件下连续注入３粒１．０ｍｍ弹丸,获得了加料实验的最好参数：等离子体中心密度ｎｅ（０）＝５．３×１０１３ｃｍ－３,总体储能Ｗｐ＝６．０ｋＪ,τｅ＝２６ｍｓ。用ＣＣＤ相机拍摄了弹丸消融云的照片,并对消融过程进行了简要的分析。结果证实,消融的不对称和弹丸轨迹的偏转是电子侧消融强于离子侧的结果,弹丸发射间隙及完整性对密度扰动有重要的影响。     

Semileptonic Decays of Heavy Mesons to Light Pseudoscalar Mesons in the BS Formalism

The decay processes from heavy to light pseudoscalar mesons such as π, K, η,η' are studied in a relativistic constituent quark model based on the BS formalism. It is emphasized that the negative energy projector operators's contributions in the BS wavefunctions for light pseudoscalar mesons have to be considered. By taking into account these contributions, the previously encountered difficulties in calculating the decay constants and form factors are found to be removed. A11 the form factors for transitions such as D→π, D→K, D_s→K, D_s→η, D_s→η', B→π, B_s→K are estimated and the branching ratios for these semileptonic decays are calculated. The results of our calculations are consistent with experimental values.     

基于群表示论的微波等离激元谐振器模式响应研究

作为光频段局域表面等离激元的低频对应物,人工局域表面等离激元因其深亚波长局域场增强和高Q值谐振的特点而受到广泛关注。微波等离激元谐振器是产生人工局域表面等离激元的典型器件,其特点是具有多重离散旋转对称性和镜面反射对称性。以往的研究提出了等效媒质法和等效色散法分析微波等离激元谐振器的模式响应,但这两种方法都未能充分考虑谐振器的几何对称性从而未能全面揭示其模式特性。本文针对谐振器的几何对称性提出了群表示论方法分析其模式响应。通过对称性分析,发现谐振器的几何对称性所构成的群的不可约表示数等于谐振器所能支持的人工局域表面等离激元模式的数目。以对称性构成C_7v群的谐振器为例,C_7v群的5个不可约表示数对应了5种人工局域表面等离激元模式,分别为零阶模式(也即磁偶极子)、偶极子、四极子、六极子和十四极子。受限于几何对称性,谐振器将不能支持更多阶的模式。为验证群表示论方法,设计了对称性构成C_7v群的微波等离激元谐振器,全波仿真结果很好地证明了上述理论。本文提出的群表示论方法也可推广到其他频段如光频,因而具有广泛的适用性。     

基于媒体报道的Filippov传染病模型的全局动力学

在经典传染病模型的基础上,通过考虑阈值策略,研究了一类基于媒体报道的不连续的传染病模型.利用Filippov意义下的右端不连续微分方程理论,对阈值策略下传染病模型的动力学行为进行了定性分析,并利用Poincaré映射研究了无病平衡点、地方病平衡点及伪平衡点的全局渐近稳定性.     

Cross‐linking induced thermoresponsive hydrogel with light emitting and self‐healing property

Development of self‐healing hydrogels with thermoresponse is very important for artificial smart materials. In this article, the self‐healing hydrogels with reversible thermoresponses were designed through across‐linking‐induced thermoresponse (CIT) mechanism. The hydrogels were prepared from ketone group containing copolymer bearing tetraphenyl ethylene (TPE) and cross‐linked by naphthalene containing acylhydrazide cross‐linker. The mechanical property, light emission, self‐healing, and thermo‐response of the hydrogels were investigated intensively. With regulation of the copolymer composition, the hydrogels showed thermoresponse with the LCST varied from above to below body temperature. At the same time, the hydrogels showed self‐healing property based on the reversible characteristic of the acylhydrazone bond. The hydrogel also showed temperature‐regulated light emission behavior based on AIE property of the TPE unit. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 869–877     

Synchronization of inventory and transportation under flexible vehicle constraint: A heuristics approach using sliding windows and hierarchical tree structure

This paper investigates the integrated inventory and transportation planning under flexible vehicle constraint. To offer better services at lower prices, more and more companies turn to outsource transportation functions to other professional service providers, namely 3rd party logistics companies. Under these vehicle rental arrangements, the number of vehicles is a decision variable instead of a fixed number, and the transportation cost includes not only the delivery cost but also the cost of vehicle rental that is proportional to the number of vehicles rented in a given planning horizon. In this paper, the problem is formulated as a mixed integer programming problem. A heuristic algorithm is developed, in which sliding windows are applied to approximate the problem by repeatedly solving a series of overlapping short-term subproblems, and a hierarchical tree structure is used to evaluate the closeness of different groups of retailers. Numerical experiments show that a better tradeoff between the inventory cost and transportation cost can be achieved through the proposed heuristic algorithm.     

Capacitated dynamic lot sizing problems in closed-loop supply chain

In this paper, we address the capacitated dynamic lot sizing problem arising in closed-loop supply chain where returned products are collected from customers. These returned products can either be disposed or be remanufactured to be sold as new ones again; hence the market demands can be satisfied by either newly produced products or remanufactured ones. The capacities of production, disposal and remanufacturing are limited, and backlogging is not allowed. A general model of this problem is formulated, and several useful properties of the problem are characterized when cost functions are concave. Moreover, this problem is analyzed and solved to optimality using dynamic programming algorithms under different scenarios. It is shown that the problem with only disposal or remanufacturing can be converted into a traditional capacitated lot sizing problem and be solved by a polynomial algorithm if the capacities are constant. A pseudo-polynomial algorithm is proposed for the problem with both capacitated disposal and remanufacturing. The problem with capacitated production and remanufacturing and the problem with uncapacitated production and capacitated remanufacturing are also analyzed and solved. Through numerical experiments we show that the proposed algorithms perform well when solving problems of practical sizes. From the experimental results also indicates that it is worthwhile to expand the remanufacturing capacity only when returned products exist in a relatively long planning horizon, and production capacities have little effect on the remanufacturing plan when the demand is mainly satisfied by the production.     

Bogner-Fox-Schmit元的超收敛

Superconvergence of the Bogner-Fox-Schmit element for the biharmonic equation is presented. The convergence rate can be increased from two order to four order by the interpolated postprocessing.in H^2-norm on the general rectangular meshes.