Thermal degradation of BaAl2Si2O8：Eu2＋ phosphor excited by near ultraviolet light

Eu2+ doped BaAl2Si2O8 phosphor was synthesized by one-step calcination of precursors that were prepared by chemical co-precipitation.The thermal degradation properties of BaAl2Si2O8:Eu2+ were investigated by photoluminescence,lifetime and chromaticity coordinate measurements.BaAl2Si2O8:Eu2+ is efficiently excited by incident light of 250-400 nm,which matches the emission of near ultraviolet LED chips well.BaAl2Si2O8:Eu2+ exhibits broad blue emission at 470 nm because of the 4f65d1-4f7(8S7/2) transition of Eu2+ ions,and the emission band shows an unusual blue shift with bandwidth broadening and emission intensity decreasing as the annealing temperature is increased.The luminescence decay and CIE chromaticity coordinates of BaAl2Si2O8:Eu2+ were determined to investigate its application in white LEDs.     

AlCl3催化1,1,1-三甲基-2,2,2-三氯二硅烷裂解的理论研究

结合采用DFT（B3LYP）及二级微扰方法对AlCl3催化1,1,1-三甲基-2,2,2-三氯二硅烷裂解反应的机理进行了研究.通过计算数据结果表明,此裂解反应为放热反应,理论产率比较高.反应可以同时按2种通道进行,其中通道2反应较为容易,其3步反应的焓变依次为：ΔH1（86.963 kJ.mol-1）,ΔH2（-237.596 kJ.mol-1）,ΔH3（-127.568 kJ.mol-1）.通道2的各步正反应活化能数值表明,第3步为速控步,其正反应的活化能E3为214.913 kJ.mol-1.     

基于云平台的软件服务流引擎技术研究

传统的工作流自动化处理大多是针对固定的较为简单的执行单元,不能适应复杂的SaaS服务要求。为同时向大规模访问用户提供可靠实时的云计算服务,文章设计了软件服务流,高效、实时、稳定的调度算法是软件服务流成功实施的关键。通过服务抽象过程把复杂的用户自定制请求匹配成云平台的可执行单元后,软件服务流引擎利用文中提出的EOE实时调度算法处理用户请求,交付下层执行,监控执行进程、系统状态,实现软件服务流的自动化高效运行。最后,给出了在海洋环境信息云服务体系框架下的实现。     

In vitro study of poly(ethylene carbonate) as a drug-eluting stent coating

An in vitro feasibility study of the use of poly(ethylene carbonate) (PEC) as a biodegradable coating material for drug-eluting stents is reported, and the performance of PEC is compared with that of poly(lactic-co-glycolic acid) (PLGA). Scanning electron microscopy (SEM) images of PEC and PLGA discs after treatment with an alkaline KO2 solution as a superoxide source showed that the PEC maintained its integrity whereas holes and small particles appeared during the treatment of PLGA. Sirolimus and paclitaxel were loaded into PEC and PLGA in order to study drug release performance. Attenuated total reflectance–infrared (ATR– FTIR) spectroscopy of sirolimus, PEC and the sirolimus-loaded PEC coating showed that no chemical reaction occurred between sirolimus and PEC. The results of atomic force microscopy (AFM) revealed that the mean roughness (Ra) values of the bare metal stent (BMS) and the drugeluting stent (DES) were 2.3 nm and 1.0 nm, respectively. After balloon expansion experiments, no delamination or destruction of the PEC coating was observed. The drug release profile of sirolimus was different from that of paclitaxel when PEC was employed as the drug carrier, and the release curves of sirolimus were different when PEC and PLGA were used as drug carriers. All the experimental results demonstrated that PEC was one of the best potential stent-coating materials.     

若干与Lipschitz条件有关的Hadamard型不等式

给出满足Lipschitz条件的凸函数的一些Hadamard型不等式,推广了已有文献的结果.     

荷叶水提液的絮凝优化工艺及其失活动力学研究

为考察复合絮凝剂(壳聚糖、单宁)的絮凝活性,优化荷叶水提液絮凝工艺条件,对絮凝剂的投加量、温度、搅拌速度进行了水平正交实验.实验结果表明荷叶水提液的最佳工艺条件为:壳聚糖投加量为1.071g/L,单宁投加量为5.357g/L,温度为30℃,转速为60r/min.并在此工艺条件的基础上进行絮凝剂的失活动力学实验研究.实验表明,荷叶水提液在25℃—30℃范围内絮凝选择性好,絮凝活性高;高于30℃时,絮凝活性显著下降.同时验证了复合絮凝剂的失活动力学符合一级反应的失活动力学模型,并讨论了时间、温度同絮凝率及黄酮损失率的关系,并由此推算出失活速率常数、活化能等动力学函数值.为荷叶水提液的絮凝工艺研究及操作条件的选择提供了有价值的理论依据.     

中国城镇居民收入不确定性与消费问题研究

文章梳理了中国城镇居民收入分配制度的变迁,指出改革开放后我国的收入分配制度得到不断的完善,中国城镇居民收入水平得到了迅速提高。收入结构呈现出多元化趋势,收入中的不确定性因素也逐渐增加,从而增强了其对未来的不确定性预期,加大了储蓄力度,这是造成长期以来城镇居民消费率不断降低的主要原因。提出降低城镇居民不确定性因素,提高城镇居民消费率的途径。     

哈尔滨市图书馆总分馆制的发展现状及存在问题

阐述了哈尔滨市图书馆总分馆三级服务体系的产生及发展现状,指出了哈尔滨市图书馆总分馆三级服务体系存在的问题,展望了图书馆的发展前景。     

试论高校图书馆服务创新与馆员职业规划

从服务理念、服务内容、服务方式等方面就当今大环境下高校图书馆如何服务创新进行了分析,并阐述了在图书馆服务创新背景下馆员的职业规划及二者之间存在的有机联系。     

20世纪70年代后民族植物学学科发展史评述

民族植物学虽有效地结合了传统知识和科学知识,将多学科的研究方法融于一身,但其核心方法为经典民族植物学的方法.本文借此为研究初衷,通过文献和数据分析,对20世纪70年代后的不同维度下的民族植物学学科发展进行评述,分析了区别于纯科学研究的学科特点及研究方法,目的是让公众了解民族植物学;对将传统知识知识产权化及用纯植物学方法研究民族植物学给予批评,以期对民族植物学领域工作者有所启示,思考学科发展.