欧洲重拳出击挑战Google

导语：由法德两国联合推动，诞生于去年四月的欧洲搜索引擎研发计划，即将于今年夏天投入实施阶段。     

华为3COM构筑下一代电子政务好网络

华为3Com公司认为电子政务网面对四个挑战:业务层面、网络层面、安全层面和管理层面。业务层面的挑战包括,各种政务应用无法做到安全隔离;各种政务应用对网络资源的要求不同;政务应用变化要求网络随需而变。网络层面的挑战包括:网络资源利用效率低下;各种业务网络缺乏有效融合;     

Modeling water and carbon fluxes above summer maize field in North China Plain with back-propagation neural networks

INTRODUCTION Dynamics of carbon and water vapor fluxesexchange between the atmosphere and the ecosystembiosphere, depend on complex and non-liner interplayamong physiological, ecological, biochemical andedaphic factors and meteorological conditions (Jarvis,1995; Leuning et al., 1995). There are many studiesquantifying the fluxes across different time and spacescales as well as assessing the environment con-straints on them by some kinds of biophysical orempirical models whose resul…     

莫高窟第285窟南壁多光谱无损分析初步报告(Ⅰ)

本文在多光谱成像调查成果的基础上,利用反射式光谱仪、数字显微镜等非介入式的光学调查仪器,结合实验室模拟试验和洞窟调查,对莫高窟第285窟南壁的无机颜料和有机染料进行了初步研究.     

中学信息技术教学几点做法

中小学信息技术教学的主要目的是让学生在了解计算机文化、初步掌握一些计算机基本知识和技能的同时，进一步激发学生的学习兴趣、增强信息意识和创新意识、有效培养学生对信息的收集、处理、应用和传输的能力．培养学生的自学能力和创造能力。[第一段]     

Sol-Gel Synthesis and Luminescence of Green Light Emitting Phosphors Zn2SiO4/Mn^2＋

MN2 DOPED ZN2SIO4 PHOSPHORS WERE SYNTHESIZED BY SOL-GEL METHOD, AND THE INFLUENCE OF ZINC SOURCE. MN2 DOPANT CONCENTRATION AND ANNEALING TEMPERATURE WERE INVESTIGATED. RESULTS SHOW THAT ZINC NITRATE BASED PRECURSOR WITH STRONG GREEN EMISSION INTENSITIES IS BETTER THAN ZINC ACETATE BASED PRECURSOR. THE INTENSITY OF GREEN LIGHT EMISSION REACHES A PEAK AT 254 NM WHEN THE MN2 DOPANT CONCENTRATION IS ABOUT 5%( MOLAR PERCENTAGE). STRUCTURAL DETAILS OF THE PHOSPHORS WERE EXAMINED THROUGH X-RAY DIFFRACTOMETRY. THERMOGRAVIMETRIC AND DIFFERENTIAL THERMAL ANALYSIS. THE RESULT INDICATES THAT THEY ARE BOTH RHOMBOHEDRAL STRUCTURES, WHICH REMAIN AMORPHOUS BELOW 700 ℃ AND CRYSTALLIZE COMPLETELY AROUND 1 000 ℃. THE LUMINESCENT PROPERTIES OF ZN:SIO4/MN2 PHOSPHORS WERE CHARACTERIZED BY EXCITATION AND EMISSION SPECTRA.     

On the Nature and Role of English in Asia

The present paper is divided into eight sections:introduction,the global diffusion of English,perceptions of the new varieties,the issue of intelligibility,features that cause unintelligibility,need for a broader pragmatics,and pedagogical impli- cations,and conclusion,followed by the references.Not surprisingly,the global spread of English has generated varying perspec- tives on the nature and functions of its acculturated varieties.Broadly speaking,the debate has divided scholars into two camps holding diametrically opposing views on the multiple versions of English.On the one hand,some scholars view variations as symp- toms of linguistic degeneration and deterioration;on the other hand,some scholars legitimize them as inevitable manifestations ne- cessitated by the demands of the new cultural contexts.The normative view of the former camp stems,at least partly,from the problems the new forms of English pose in terms of international intelligibility.It is in this context that the paper examines the traditional,one-sided,native speaker-centred idea of intelligibility and the recent two-sided view of intelligibility that places the onus on both the native speaker and the non-native speaker.The argument of the latter camp is based on the premise that the new varieties require a broader pragmatic framework,because universal pragmatics is inadequate to describe them satisfactorily. Thus,the camp advocates a need for a language specific pragmatics,and a comparative pragmatics,in addition to the traditional universal pragmatics.Logically,the debate on phonological,lexical,grammatical,and discourse structure variations,and their le- gitimacy has prompted English language teaching specialists to have a fresh look at the goals and objectives of teaching English in the countries of the outer and expanding circles,and accordingly prioritize the teaching of national and regional varieties over that of the so-called native varieties.Thus,the paradigms of independence and centrality of the new varieties are replacing the paradigms of their dependence and marginality.     

农业中的放射性同位素

原子核的秘密的揭露,使人类掌握了新的無穷尽的能源。第一座原子能电站在苏联的建立,为將这个能源实际利用于工業和农業的和平目的,奠定了基础。原子技术的發展,开辟了把放射性同位素应用到各种全然不同的科学技术部門中去的广闊的可能性。人工取得放射性同位素的方法之一,是在原子核反应堆中用中子来照射。比如,用中子照射普通的天然的磷的时候,部分的磷原子核就和中子結合而变成磷的放射性同位素(磷-32)的原子核。当放射性磷的核衰变的时候,核中的一个中子轉化成質子,同时放射出一个β粒子(帶陰电的电子)。衰变是按照这个方式發生