Thermal properties of high-k Hf1-xSixO2

Classical atomistic simulations based on the lattice dynalnics theory and the Born core-shell model are performed to systematically study the crystal structure and thermal properties of high-k Hfl-xSixO2. The coefficients of thermal expansion, specific heat, Griineisen parameters, phonon densities of states and Debye temperatures are calculated at different temperatures and for different Si-doping concentrations. With the increase of the Si-doping concentration, the lattice constant decreases. At the same time, both the coefficient of thermal expansion and the specific heat at a constant volume of Hf1-mSixO2 also decreases. The Griineisen parameter is about 0.95 at temperatures less than 100 K. Compared with Si-doped HfO2, pure HfO2 has a higher Debye temperature when the temperature is less than 25 K, while it has lower Debye temperature when the temperature is higher than 50 K. Some simulation results fit well with the experimental data. We expect that our results will be helpful for understanding the local lattice structure and thermal properties of Hf1-mSixO2.     

"移动家庭影院"银幕之佳选--OS Smart&Steady G1投影幕

随着人们居住条件的改善，经济收入的提高，许多家庭都有了购买一套家庭影院的计划。以投影机为代表的越来越多的视频产品开始粉墨登场，成为吸引观众和影音发烧友的新卖点，大画面的家庭影院视觉效果越来越受到消费者的关注和青睐。家用投影机在不久的将来，将成为一股新的消费潮流。但是，家庭影院在大家的印象中可能还只是停留在大屏幕电视．音响．功放．DVD播放机这几样设备上，而事实上，现在很多发烧友已经开始使用投影机作为影像输出设备，因为使用投影机，就能按照实际环境需要，按自己的喜好来调节画面的大小，再配上原有的音响等设备，就能如真正置身于电影院中一样，享受到超级震撼的影音效果。     

线性算子与右端项都近似给定的有限维正则化方法

本文利用有限维正则化方法来求解线性算子与左端项皆有噪声时的问题，并给出了该方法的误差估计及正则参数选取的标准。     

五月“物”语

2004年的夏天终于在这个王月大张旗鼓登场了。在每次迎面而来的新鲜空气中，我们的视觉世界不仅需要美感，需要大牌，更需要供我们想象的空间，即使没有人，即使记不住谁的名字。     

电喷雾离子源原理与研究进展

电喷雾离子源(ESI)是蛋白质组学研究采用的LC-MS/MS中最常用的接口之一,其作为一种软电离技术,具有可直接测定热不稳定化合物、形成多电荷离子等特征,在蛋白质组学研究中具有独特优势.本文介绍了电喷雾离子源(ESI)的工作原理与研究进展,并对各种新型离子化方法与应用进行了系统评述.     

HL-2A装置中性束注入器钛吸附泵的设计

HL-2A装置NBI的设计参数为，注入气体为氢气、束能量60keY、束脉宽2s、两条束线切向注入、最终达到总的中性束注入功率4MW。目前，初步方案拟定为一条束线安装两个离子源，束线真空部分由一个主真空室和一个次真空室以及离子源真空室和漂移管道构成。     

数字教室

经济学散文四大侠 现代社会是一个纯粹的经济社会,每个人都面临选择的问题,懂点经济学是大势所趋。但充满抽象推理、图形和公式的经济学教科书和专著总是让大众读者望而生畏,新闻体的文章又往往仅是一时的轰动效应。惟有学术散文才能以轻松的文字表达出大众接受的深邃思想。 优秀的经济学散文高手必须具备深厚的经济学理论功底,敏锐的观察力和非凡的文学修养以及飘逸洒脱、举重若轻的文字工夫。在经济学散文领域有四大侠之谓:以高深莫测运笔如飞著名的“飞侠”林行止;狂傲不羁如神似鬼的“游侠”张五常;以笑声惊倒学界的“大侠”王则柯和被称为“经济学巨侠”的熊秉元。     

以太接入的可行性

以太网是目前使用最广泛的局域网技术。由于其简单、成本低、可扩展性强、与IP网能够很好地结合等特点，以太网技术的应用正从企业内部网络向公用电信网领域迈进。以太网接入是指将以太网技术与综合布线相结合，作为公用电信网的接入网，直接向用户提供基于IP的多种业务的传送通道。     

HL-2A装置主机真空性能的改善

HL-2A装置真空室内部件数目繁多，容器本体上的密封部位多达几百个，特别是真空室内多极场线圈真空套从真空室的预装阶段开始，经常会出现一些漏气问题，此问题在原ASDEX运行时就是一个棘手的问题，已进行了多次修补。大部分漏点均发生在厚度仅为约0．2mm的波纹管上，无法采用氩弧焊接，所有这些漏点的修补均采用无铅焊料通过钎焊工艺完成。     

Diffraction Properties for 1000 Line/mm Free-Standing Quantum-Dot-Array Diffraction Grating Fabricated by Focused Ion Beam

In the research of inertial confinement fusion （ICF）, diagnosis of soft x-ray spectra radiated from pellet implosion is a crucial approach to compre- hend the space-time characteristic of plasma and the laser-plasma interactions. Conventional black- white transmission grating （TG） as a speetrophotom- etry element has been widely used in the region of op- tical measurements. However, the inherent high-order diffraction of black-white TG can overlap the informa- tion from the first order diffraction. The uncertainty of unfolding the complex process is the main diffi- culty in precise spectral analysis, which greatly hin- ders being able to stripe out the reasonably physical information. Quantum-dot-array diffraction grat- ing （QDADG） proposed by Cao, where the trans- mittance distribution obeys the sine form exactly, is an ideal amplitude TG and has perfect properties of pro- ducing just one pair of conjugate first order diffraction lines and suppressing the high order diffraction.The traditional fabrication technique for QDADG is the electron beam lithography （EBL） and the x-ray lithog- raphy （XRL）. Owing to its capability of gen- erating patterns and the high resolution, EBL plays an increasingly important role in the micromachining, and is recognized as the main approach of fabricating a mask. The fabrication of nanoscale patterns with steep cross section is the superiority of XRL, which possesses the advantages of high efficiency, nanoscale resolution and great penetration capability. On the basis of the above-mentioned processing technique, 1000 line/mm quasi-sinusoidal single-order diffraction TG with the minimal feature structure of 500 nm was reported by Kuang et al., and can be applied in the ICF research. For single order diffraction grating, unfortunately, the promotion and application of EBL and XRL are restricted by the complex process, long period, difficult manufacture and the existence of the supporting film that absorbs x-rays and distorts the light information.