Synthesis,Characterization and Luminescent Properties of Complexes of Rare Earth Nitrates with Tris{2-[N-(pyridine-methanoyl)amino]ethyl} amine

Duringthelastdecade ,thedesignandsynthesisoftripodalligandsandtheirmetalcomplexeshaveattractedconsiderableattentionduetotheirpotentialusesaslumi nescentprobesinmedicineandbiochemistry[1～ 7] ,ascatalysts[8] andelectrochemicalmaterials[9] .However ,thecomplexesofrareearthmetalwithtripodalligandshavefewreported[10 ] .Asanextensionofourstudiesoncomplexesofmetalwithtripodalligands ,anewtripodalligand (tris { 2 [N (pyridine methanoyl)amino]ethyl}amine ,L)anditscomplexeswithrareearthnitratesweresyn…     

Characteristic Investigation of Nano-Crystal Hydrogen Storage Alloys

A Ml (NiCoMnA1)5 hydrogen storage alloys was prepared by double-roller rapid quenching.Its microstructure, electrochemically and kinetic characteristic were studied.A uniform crystal phase with CaCu5 structure could be detected by XRD analyses, whose average grain size is 30 ～ 50 nm and the ratio of c/a of nano-crystal hydrogen storage alloy is larger.The hydrogen absorption/desertion p - C isotherms of alloy show that its fiat-performance is perfect and the magnetic stagnant effect is very little.An simulate cell is used for electrochemical measurement.Electrode is 10C, the capacity decreasing rate via the 450 cycles at 7C is less than 20%.     

继续奏响振荡向上主旋律——2002年白银市场回顾及其2003年展望

本文对2002年国际国内白银市场做了全面分析,对2003年白银市场走势进行了分析预测。白银作为一种贵金属,同时又具有工业金属的特性,世界经济形势,世界政治局势的变化,都对白银价格走势产生影响。鉴于该金属的双重特性,本文就从白银的供应、需求、消费及世界经济的发展等方面论述白银市场前进趋势。     

Integration of batching and scheduling for hot rolling production in the steel industry

This paper investigates the hot rolling production scheduling problem in the steel industry and proposes a new mixed integer programming model for this problem based on the monolithic modeling strategy that integrates batching and scheduling. Using this strategy, the new model can simultaneously schedule multiple turns and simultaneously determine the production timetable of these turns in a global optimal view. A long-term tabu search heuristic using frequency-based memory is developed to obtain near-optimal solutions for this problem. Three kinds of speed-up strategies are developed to accelerate the search procedure of the proposed tabu search. A practical scheduling system combining the proposed mathematical model and the tabu search heuristic has been developed and tested on instances collected from practical production data. The experimental results show that the proposed mathematical model and the tabu search heuristic outperform both the current manual scheduling method and the traditional serial method.     

乳化炸药的乳化物理模型和理想乳化模态

文章以平推流模拟了乳化炸药乳胶质的形成过程,并建立了机械强制乳化的物理模型及理想模态。     

Child abuse in Hong Kong revisited after 15 years: characteristics of victims and abusers

The purpose of this paper was to examine the characteristics of the victims and abusers of child abuse cases on the Child Protection Registry in Hong Kong as of March 1995 and to compare findings with a similar community report of child abuse in Hong Kong conducted approximately 15 years earlier. As of March 31, 1995, there were 457 active cases of child abuse or suspected child abuse (44% male and 56% female) on the computerized Child Protection Registry. Fifty percent of the victims were grade school age children between 7-12, and 62.4% suffered physical abuse. The abusers or suspected abusers were 52% male and 48% female with nearly half (49%) in their thirties. The majority of abusers were married/cohabiting (75%) with only a grade school education (60%). As compared to 1979, there was an increase of sexual child abuse cases, female victims of child abuse, and an increase in male abusers or suspected abusers.     

高Q Ba(Zn_(1/3)Ta_(2/3))O_3介质谐振器材料及其在毫米波系统中的应用

叙述了Ｂａ（Ｚｎ１／３Ｔａ２／３）Ｏ３介质谐振器材料的制备、结构、微波性能及典型应用。Ｂａ（Ｚｎ１／３Ｔａ２／３）Ｏ３介质材料介电常数εｒ为２９．５，频率温度系数τ≈０（－５５～＋８５℃），１０ＧＨｚ下最大无载Ｑ值１４７００，在２８ＧＨｚ测得Ｑ值约为４８００。这种材料具有高Ｑ值，特别适用于Ｘ以上波段作为振荡器电路中频率稳定元件。用这种介质谐振器已研制出８ｍｍ介质稳频微带耿氏振荡器，频率稳定度小于１０×１０－６／℃，最大输出功率达１８０ｍＷ。     

多孔硅发光的物理机制——纳米量子限制效应及表面态在发光中的作用

采用阳极氧化腐蚀的方法制备了多孔硅（ＰＳ），这种ＰＳ的微结构为纳米量级的，并具有光致发光特性，这无疑将对全硅光电子学的发展具有很大意义。根据大量实验与理论分析，提出了这种ＰＳ发光的物理机制：纳米量子限制效应和表面态及其物质在发光中的作用，从量子力学的薛定锷方程出发，用沟道势阱的近似模型，推导得到进入量子线的电子和空穴的能量势垒，ＰＳ的有效带宽Ｅ＝Ｅ＿０＋ΔＥ，对于Ｓｉ（Ｅ＿０＝１．１２ｅｖ）。完美地解释了目前在ＰＳ研究中的ＰＬ谱的篮移现象。     

激光对改变胰岛致免疫性的影响

新生猪胰岛样细胞团经准分子激光照射预处理后，其免疫原性明显降低，表明经激光预处理，有可能延长移植物存活时间。     

PbO－Bi_2O_3－B_2O_3－SiO_2系重金属氧化物玻璃的结构与光学性

通过密度、可见光光谱、红外吸收光谱、Ｃｏ－６０辐照损伤试验及荧光光谱的测试，研究了ＰｂＯ－Ｂｉ２Ｏ３－Ｂ２Ｏ３－ＳｉＯ２玻璃系的光学性能与结构．密度最高可达８．４６４ｇ／ｃｍ３其紫外吸收达截止波长随Ｐｂ２＋及Ｂｉ３＋含量升高而红移．玻璃熔化温度低达８５０℃．在ＰｂＯ－Ｂｉ２Ｏ３－Ｂ２Ｏ３系玻璃中加人ＳｉＯ２可使玻璃结构更致密．室温下该系统玻璃在３６０ｎｍ有一个宽的激发峰，能产生４１８ｕｍ及４３８ｕｍ两个弱的发射峰．该系统玻璃的结构是由［ＳｉＯ４］４－、［ＢＯ３］３－、［ＢＯ４］５－、［ＰｂＯ４］６－及［ＢｉＯ６］９－构成．其中部分Ｐｂ２＋及Ｂｉ３＋以网络外体进入玻璃．