Theoretical Studies on Nitrogen, Cesium and Aluminum Doped Carbon Cluster Anions CnN7–(n=5~14), CnCs–(n=2~12) and CnAl2–(n=1~8)

Abstract The dissertation was devoted to the theoretical studies on N-doped carbon cluster anions CnN7-(n=5~14), Cs-doped carbon cluster anions CnCs-(n=2~12) and Al-doped carbon cluster anions CnAl2-(n=1~8). For CnN7-(n=5~14) and CnAl2-(n=1~8), molecular models were optimized by means of B3LYP/6-311G* method, combining Molecular Graphics and Molecular Mechanics to ascertain the lowest-lyin...学位：理学硕士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：20032506

Analysis on the Inconsistent Causes Between the Development of Higher Education and Social Economy in Philippines After World War Two

依据教育外部规律可知，一个国家的经济、政治和文化对本国高等教育有着决定性作用，反过来高等教育对本国的经济发展和政治文化建设有着促进和限制的作用。理想状态下，二者的协调发展可以促进彼此的健康发展和良性循环，但实际生活中并非如此。尤其是在政府战略性决策不利的情形下，二者之间不协调发展的弊端更是影响深远。本论文以菲律宾为案例，探讨了菲律宾高等教育与社会经济发展之间不协调的原因。菲律宾高等教育与社会经济发展长期以来都处于一种不协调的状态，主要表现为高等教育人才培养总量和结构与社会经济发展所需脱节，从而导致大量受过高等教育的人才海外就业。针对这个问题，本论文从三个方面着手。首先对菲律宾高等教育的发展进行...According to the external law, one country’s economy, polity and culture are main determinants in the development of higher education which can enhance or limit the advance of economy and progress of polity and culture. Ideally, the consistency between them can accelerate their healthy development and well run, but it does not always so. Especially, the circumstances, under which the government ha...学位：教育学硕士院系专业：教育研究院_比较教育学学号：2005130271

An Analysis of Inconsistency between the Development of Higher Education and the Economy in Philippines

高等教育与社会经济发展的最佳状态是相互协调、彼此促进。在菲律宾,价值取向的影响以及高等教育专业设置与社会经济发展脱节等导致了这两者之间发展的不协调,政府与高校虽然做了不少努力,但效果并不显著。其经历启示我们:影响高等教育发展的内外部因素众多,二者之间的协调发展只能得益于多方的共同努力。The best relationship between higher education and economy is that they are well coordinated and help each other forward.In this respect,we can learn lessons from Philippines.Only by cooperative efforts,can the consistent development of the two be realized,because there are many factors within and out of higher education

Research on High S/P of Phosphor-type White LED with High Color Temperature

对于白光照明而言,显色指数(CRI)和暗视觉下光通量与明视觉下光通量的比值(S/P)是衡量白光光源质量的两个重要参数。CRI反映的是待测光源下物体色彩还原能力;而S/P值越高的光源下人眼视物越清晰,对节能也具有一定作用。一般而言,这两个参数越高越好;然而在实际中,两者是一对矛盾体。当前的大部分白光光源的S/P值普遍低于2.5。白光发光二极管(LED)具有光谱可调特性,因此可以通过优化光谱,在满足一定的CRI下获得更高的S/P值。首先模拟光谱,然后通过计算机编程调节光谱峰值波长、相对光强度等光谱参数,最终获得高色温(6 500 K)下高S/P值光谱,对于节能照明光源设计具有重要参考价值。For white light illumination, color rendering index(CRI) and scotopic/photopic(S/P) ratio are twocritical parameters to evaluate the quality of white light source. The CRI is introduced to describe the color fidelityof objects under tested light sources. Under light sources with higher S/P values, human eyes can see more clearly,and it also has a certain effect on energy saving. In general, the higher is the values of the two parameters, the quali-ty of the illumination effect is better. However, there is a trade-off between them. The S/P value of most of the cur-rent white light sources is generally less than 2.5. White light emitting diode(LED) has spectrum adjustment charac-teristic, so higher S/P value is obtained under the condition of meeting the certain CRI through optimizing spectrum.Firstly, LED spectrum is simulated, and then spectrum parameters such as spectrum peak wavelength and relativelight intensity are adjusted through computer programming. Finally, high S/P value spectrum under the high colortemperature of 6 500 K is obtained, which has an important reference value for energy-saving illumination lightingsource design.中德国际科技合作项目(2015DFG62190

Study on overlapping process in laser transformation hardening of stamping die

针对激光相变强化搭接带存在的回火软化等问题,对激光强化的球墨铸铁材料QT700-2搭接区的显微硬度、表面粗糙度、物相变化等进行了测试,并分析了强化机理。结果表明:选用合理的搭接率等工艺参数,球墨铸铁激光搭接强化后的硬度可达到50HRC以上,调节搭接宽度可以避免搭接区的回火软化问题。多道搭接强化后表层的马氏体组织呈区域性交错分布,材料表面形成非均匀、多尺度强化结构,强化后的表面具有良好的耐磨性和耐疲劳性。通过上述结果,对材料激光搭接强化的工艺参数进行了合理的优化

冲压模具激光表面强化的搭接工艺研究

针对激光相变强化搭接带存在的回火软化等问题,对激光强化的球墨铸铁材料QT700-2搭接区的显微硬度、表面粗糙度、物相变化等进行了测试,并分析了强化机理。结果表明：选用合理的搭接率等工艺参数,球墨铸铁激光搭接强化后的硬度可达到50HRC以上,调节搭接宽度可以避免搭接区的回火软化问题。多道搭接强化后表层的马氏体组织呈区域性交错分布,材料表面形成非均匀、多尺度强化结构,强化后的表面具有良好的耐磨性和耐疲劳性。通过上述结果,对材料激光搭接强化的工艺参数进行了合理的优化

Effects of long-term applying micronutrients fertilization on wheat yield and N and P uptake in dryland of Loess Plateau

以长达18年的微量元素肥料定位试验为背景,研究了长期施用微肥对小麦产量及氮磷养分吸收量的影响。结果表明,在施NP肥的基础上施Zn、B、Mn可显著提高小麦生物学产量,较NP+KH2PO4分别提高6%以上;施Zn、B可显著提高小麦籽粒产量,较NP增产分别为5.5%和6.0%,较NP+KH2PO4分别增产8.4%和8.9%;施Cu使小麦吸氮量提高3.1%,吸磷量提高7.7%,较NP+KH2PO4吸氮量、吸磷量分别提高6.0%和5.5%;施Zn使小麦吸氮量提高4.1%,吸磷量提高2.5%,分别较NP+KH2PO4处理吸氮量、吸磷量分别提高8.0%和6.9%;同时,施Zn、Mn、Cu肥较NP+KH2PO4更有利于籽粒对氮素的吸收

A Density Functional Study on the Structures and Energies of C_nP_2~+ (n=1~7) Clusters

[中文文摘]使用分子图形软件设计出多种CnP2+(n=1～7)的结构模型,并进行B3LYP密度泛函几何构型优化和振动频率计算.通过总能量的比较,最稳定的构型是具有D∞h对称性的线性结构.当n为奇数时团簇具有类似的聚炔结构性质,而n为偶数的团簇具有类似的累积二烯烃结构性质.电离能曲线具有明显地奇偶变化的规律,说明了n为奇数的团簇分子比n为偶数团簇稳定,这与激光质谱图的奇强偶弱的实验结果相符合.[英文文摘]Using molecular graphics software,numerous models of C_nP_2+ (n=1~7) have been designed.Geometry optimization and calculation on vibrational frequency were carried out by means of the B3LYP density functional method.After comparing the total energies of the isomers,it was found that the ground state structures were linear chain with D_∞h symmetry with phosphorus atoms located at the terminals.From the bond order analysis by NBO,when n is even (i.e.,in the cases of C_2P_2+,C_4P_2+,C_6P_2+),the straight chains show an alternate long2and2short pattern in bond lengths that is similar to that of polyacetylene st ructure. When n is odd (i. e. ,in the cases of C3 P2+ ,C5 P2 + ,C7 P2+ ) ,the bond lengths of C2C bonds with in the st raight chain average out and are similar to those of the cumulenic structure. The clusters with odd2n are more stable than those with even2n. The odd/ even alternation trend can be explained according to the obvious parity variation of ionization potential ,it is in good agreement with the experimental phenomena observed in mass spectrometric studies.国家自然科学基金资助项目(20473061

磁制冷材料MnFeP0.45As0.55的热力学循环性能分析

一级相变磁制冷材料MnFeP1-xAsx具有巨磁热效应,其在制冷循环中的热力学性能值得探索。本文以MnFeP0.45As0.55的等磁场热容随温度变化实验数据为基础,应用热力学分析和数值计算方法,获得0T、2T应用磁场下的熵温曲线,并设计不同温跨的多种回热Ericsson制冷循环,计算制冷循环的主要热力学参量,揭示非平衡回热量、净制冷量、性能系数等随制冷空间温度变化规律,同时还与Gd、Gd5Si2Ge2在10 K温跨时的净制冷量进行比较,结果表明MnFeP0.45As)0.55的最大净制冷量更大。国家自然科学基金资助项目(No.51776178

C_nP_4~4(n=1～7)团簇结构与能量的密度泛函研究

使用分子图形软件设计出多种CnP-4(n =1～ 7)的结构模型 ,并进行B3LYP密度泛函几何构型优化和振动频率计算 .最稳定的CP-4和C2 P-3 都是平面环状结构 .最稳定的CnP-4(n =3 ,5 ,7)结构在直碳链的一端连接 1个磷原子且另一端是P3 C的四元环的平面结构 .最稳定的CnP-4(n =4,6)结构在直碳链的一端连接 1个磷原子且另一端是P3 的三元环的锄状结构 .直碳链可与平面环的磷原子生成大π键 .大多数构型是由C2 ,C3 ,C4子结构以环状或链状方式组成的 .碳原子与磷原子以交替方式排列的结构数量少、能量高