脉冲激光沉积法在多孔硅衬底上制备ZnS薄膜

用电化学阳极氧化法制备了一定孔隙率的多孔硅样品,然后用脉冲激光沉积法以PS为衬底生长一层ZnS薄膜.用X射线衍射仪、扫描电子显微镜和荧光分光光度计分别表征了ZnS薄膜的结构、形貌和ZnS/PS复合膜的光致发光性质.XRD结果表明,制备的ZnS薄膜沿β-ZnS(111)方向择优生长,结晶质量良好,但衍射峰的半峰全宽较大;SEM图像显示,ZnS薄膜表面出现一些凹坑,这是衬底PS的表面粗糙所致.室温下的光致发光谱表明,沉积ZnS薄膜后,PS的发光峰蓝移.把ZnS的蓝绿光与PS的橙红光叠加,在可见光区450~700 nm形成了一个较宽的光致发光谱带,ZnS/PS复合膜呈现较强的白光发射.     

溶胶-凝胶法制备ZnO薄膜晶体结构和发光特性的研究

采用溶胶-凝胶（Sol-Gel）旋涂法在Si（100）衬底上制备ZnO薄膜，在室温下利用X射线衍射（XRD）、原子力显微镜（AFM）、光致发光谱（PL）等手段分析所得ZnO薄膜的晶体结构和发光特性．结果表明：当热分解温度为400℃，晶化温度为450℃～650℃时，溶胶．凝胶旋涂法制备的ZnO薄膜样品属六方纤锌矿结构，ZnO薄膜呈现沿各个晶面自由生长的特性；在室温下均有较强的紫外带边发射峰，这表明带间跃迁占了主导地位，与缺陷有关的可见发射带很弱．以上结果说明：溶胶．凝胶法制备的ZnO薄膜质量较高．     

非晶硅薄膜和结晶硅薄膜的拉曼光谱

以玻璃为衬底,利用等离子体增强化学气相沉积工艺制备了非晶硅(α-Si)薄膜,然后通过准分子激光晶化方式获得结晶硅(nc-Si)薄膜,采用激光显微拉曼光谱仪对非晶硅薄膜、结晶硅薄膜这两类薄膜的拉曼光谱效应和结晶质量等进行了定量分析。结果表明:当激光功率达到某一阈值时,非晶硅样品发生了晶化,即由非晶硅转化成了结晶硅,特征峰发生了46.8 cm-1的位移,薄膜的结晶性质发生根本变化。而结晶硅样品在激光功率变化过程中仅因能量积聚造成了薄膜内应力变化,激光能量消散后内应力恢复原来的状态,特征峰在±5.4 cm~(-1)位移内波动,薄膜的结晶性质并未发生明显变化,表明薄膜处于稳定的晶态结构。     

一维GaN纳米结构的制备、表征及其特性研究

采用在石英炉中,氨化Ga2O3薄膜的方法,在Si（111）衬底上成功了制备GaN纳米结构薄膜：纳米线、纳米棒．分别用X射线衍射仪（XRD,Rigaku D／Max--rB Cu Ka）、傅立叶红外透射谱（FTIR,TENSOR27）、扫描电子显微镜（SEM,Hitachi S-570）、高分辨电镜（HRTEM,Philips TECNAIF30）和光致发光谱对样品的结构、成分、形貌和光学特性进行了测量分析．最后,简要的讨论了其生长机制．     

沸石基纳米氧化锌抗菌性能研究

以Zn Cl2、Na HCO3和Na Y沸石为原料,通过浸渍、焙烧等工序制备出Zn O/Na Y复合材料。用X射线粉末衍射（XRD）和扫描电镜（SEM）对制备的材料进行表征,发现20-30 nm氧化锌粒子负载在Na Y沸石表面。制备的材料具有抗大肠杆菌功能,在紫外光照射下,能将大肠杆菌完全氧化分解。     

激光烧结快速合成Al2（WO4）3材料

采用激光烧结快速合成方法合成了形貌良好的Al2（WO4）3材料。扫描电镜（SEM）发现合成物样品表面组织呈树枝状,具有定向生长的趋势。能量散射光谱（EDS）分析显示合成物内部成分分布均匀。X射线衍射（XRD）分析证实合成物主要是Al2（WO4）3材料。拉曼光谱分析说明在合适激光工艺参数下可避免原料挥发,使原料完全参与反应。     

Fe3O4（100）／STO（100）薄膜的制备及磁输运特性研究

采用脉冲激光沉积方法,以烧结的Fe3O4为靶材,在STO（100）基底上制备了Fe3O4（100）薄膜。XRD和AFM显示薄膜为纯相外延单晶薄膜、表面较平整。对薄膜的磁电阻进行测量,薄膜为负磁电阻,且在Verwey转变温度（约120K）时磁电阻最大。霍尔效应测量得到薄膜中栽流子浓度随着温度的降低而减小,In（n）与I／T基本呈线性关系,符合半导体热激活模型,迁移率随着温度的降低而减小,说明在薄膜内存在大量电离杂质中心。薄膜磁滞回线中较高的饱和磁化场。说明薄膜中APBs密度较低。     

纳米二氧化锡薄膜的AFM研究

以SnCl4.5H2O作为反应前驱物,采用溶胶-凝胶法制备了纳米SnO2薄膜,对薄膜烧结的温度及时间等工艺进行了研究,得到了最佳的烧结条件,采用X射线衍射仪（XRD）及原子力显微镜（AFM）对薄膜进行了结构形貌表征。结果表明,当烧结温度为450℃时,纳米SnO2薄膜为金红石型结构,表面形貌最佳,平均颗粒约为39-45nm。     

激光焊接不锈钢的温度场数值模拟

采用有限元方法,建立了激光焊接不锈钢的三维瞬态温度场的计算模型,考虑了材料的热物理性能、相变潜热与温度的非线性关系以及表面对流换热和辐射散热等影响因素,使用SYSWELD软件对激光焊接过程中的温度场进行了分析。结果表明:在激光焊接的开始阶段和结束阶段温度快速上升,中间阶段温度变化较缓慢;沿激光束扫描方向和与扫描方向垂直的方向都存在较大的温度梯度,温度梯度的存在引起较大的热应力,而热应力的存在是焊接过程中易产生裂纹的主要原因。     

聚酰亚胺平面/调制薄膜的制备与测量

采用联苯四羧酸二酐(PMDA)和对苯二胺(PDA)为二酐和二胺,以N,N-二甲基乙酰胺(DMAc)为溶剂制备了聚酰胺酸溶液(PAA).采用旋涂工艺,以K9玻璃或调制模版为衬底,制备了聚酰亚胺(PI)平面/调制薄膜.对其厚度、结构、表面粗糙度和表面调制图形进行了测量,研究了其厚度与旋涂速度和PAA溶液浓度的对应关系.结果表明,PAA溶液在马弗炉中进行370℃热处理,可以完全转化为PI;通过旋涂法制备PI平面薄膜的平均粗糙度Ra的最大值和最小值分别为3.7 nm和3.1 nm;PI平面薄膜最小厚度为1μm,且其厚度随着旋涂速度增大而减小,随着PAA溶液浓度的增大而增大;PI调制薄膜的周期和振幅分别为100μm和4.8μm,在调制图形转移过程中,周期不变,而振幅存在0.2μm的转移误差.     

通过模式进行CIM到PIM的模型转换

Model driven architecture （MDA） is an evolutionary step in software development. Model transformation forms a key part of MDA. The transformation from computation independent model （CIM） to platform independent model （PIM） is the first step of the transformation. This paper proposes an approach for this transformation with pattern. In this approach, we take advantage of ＂reuse＂ from various standpoints. Feature model is used to describe the requirement of the application. This can help us bring ＂reuse＂ into effect at requirement level. Moreover we use pattern to transform CIM to PIM. This can help us bring ＂reuse＂ into effect at development level. Meanwhile, pattern was divided into four hierarchies. Different hierarchies of pattern are used to help us utilize reuse at different phase of development. From another standpoint, feature model describes the problem of a domain while pattern describe the problem across domains. This can help us reuse the element in and across domains. Finally, the detailed process of the transformation is given.     

师专升本后的教师教育模式探索

师范专科学校升为普通本科院校后,在围绕“多科性”进行建设的同时,也面临着对原有师范教育模式的改革与创新问题。采用什么模式,每个学校要考虑自身的具体情况。师专升本后较为适合“2 1 1”的教师教育模式。这种模式既符合目前教师教育改革的基本要求,又具有良好的操作性。     

New Diamond Block Based Gradient Descent Search Algorithm for Motion Estimation in the MPEG-4 Encoder

Motion estimation is an important part of the MPEG-4 encoder, due to its significant impact on the bit rate and the output quality of the encoder sequence. Unfortunately this feature takes a significant part of the encoding time especially when the straightforward full search(FS) algorithm is used. In this paper, a new algo-rithm named diamond block based gradient descent search (DBBGDS) algorithm, which is significantly faster than FS and gives similar quality of the output sequence, is proposed. At the same time, some other algo-rithms, such as three step search (TSS), improved three step search (ITSS), new three step search (NTSS),four step search (4SS) , cellular search (CS) , diamond search (DS) and block based gradient descent search (BBGDS) , are adopted and compared with DBBGDS. As the experimental results show, DBBGDS has its own advantages. Although DS has been adopted by the MPEG-4 VM, its output sequence quality is worse than that of the proposed algorithm while its complexity is similar to the proposed one. Compared with BBGDS, the proposed algorithm can achieve a better output quality.     

基于SLM的18Ni-300模具钢工艺参数优化

设计了以激光功率、扫描速度、扫描间距、铺粉厚度为因素的正交实验,研究了SLM 成型18Ni-300 模具钢粉末过程中各个工艺参数对成型件致密度的影响规律,并进行了工艺参数优化。实验表明,在选定范围内,成型件致密度随激光功率的增加先增大后减小?随扫描速度的增加持续减小?随扫描间距的增加先增加后减小?随铺粉厚度的增加持续减小。最优工艺参数组为激光功率260 W、扫描速度500 mm/ s、扫描间距0.11 mm、铺粉厚度0.02 mm 时,成型件致密度99.99%,为所有实验中的最优值。     

从中都(燕京)到南京(汴京):金王朝的最终覆亡(续)

蒙古势力从13世纪初崛起于蒙古草原后,即开始南向进攻金的控制区,随着力量的不断增强而步步进逼.而此时的金朝,由于制度体系的变化、军事能力的衰退和官场习气的败坏等因素的作用,迅速步入衰微阶段.金宣宗贞祐三年(1215年)的中都沦陷和金哀宗天兴二年(1233年)的南京陷落,成为金朝衰亡过程中最后二十余年的重要界碑.     

RNA干涉技术

RNAi是双链RNA介导的、序列特异性的转录后基因沉默，自1998年发现至今已有很大进展。本文综述了RNA干涉的分子机理及其应用研究进展。     

Adolescent English Learners’ Use of Digital Technology in the Classroom

This study looked at how five adolescent English Learners (ELs) in an English as a second language class use the available digital technology. Data collected consisted of classroom observations, student and classroom documents, and focus student interviews. Data collection and analysis were simultaneous processes. Findings suggest adolescent ELs use their personal smartphones and school-provided laptops on a regular basis for entertainment and scaffolding purposes.     

对垂直腔面发射激光器(VCSEL)的应用探讨

VCSEL是美国原厂生产的激光器，是光通信中的一种极具潜力的固体：激光源，是目前市场上最好的VCSEL晶片及芯片组之一，已得到了较为广泛的应用。本文介绍了以GaAs和A1GaAs作为工作物质的垂直腔面发射激光器的结构、特性和在条形码扫描中的应用。     

新世纪中国电子教育与高等教育自学考试的结合问题

本文从逻辑分析、价值分析和实证分析等不同角度,探讨了新世纪我国电大教育与自学考试的“整编”与“融合”问题。作者认为,实现两类远程高等教育形式深层次的沟通与结合,是提高办学效益、提高教学质量、加快高等教育大众化步伐、促进学习社会形成的现实需要;要采取切实有力措施,分步骤推进电大和自学考试从联合、沟通最终走向融合,使之成为我国终身教育体系的骨干和学习社会的支柱。     

Unravelling continuous assessment practice: Policy implications for teachers’ work and professional learning

Assessment policy in some countries continues to promote the use of continuous assessment (CA) within classrooms. Several policy claims have been made about the potential of CA to improve education. Using data from a 2010 evaluation of the Trinidad and Tobago Continuous Assessment Programme (CAP), canonical correlation analysis (CCA) was used to unravel the pattern of relationships between institutional variables, professional learning, teacher beliefs, and CA components. The CA components measured were (1) overall use, (2) multiple assessment formats use and (3) formative feedback use. Each CA component was shown to be associated with different variables, with overall use related to several teacher belief factors such as extra-role behaviour. However, multiple assessment formats use added only a small amount of unique variance to the CCA solution. Moreover, the canonical variate for formative feedback use was not statistically significant. These findings have implications for CA as a policy tool. Successful implementation of CA may require high quality professional learning as well as teacher workforce remodelling. Even when implemented successfully, however, CA may not be a useful vehicle for promoting high quality formative assessment or use of multiple assessment formats.