| 1. | International center for materials physics 国际材料物理中心 |
| 2. | The influence of microstructure on ceramic material physics performance 显微结构对陶瓷材料物理性能的影响 |
| 3. | Materials physics and chemistry 材料物理与化学 |
| 4. | Polymeric materials physics 高分子材料物理 |
| 5. | Zhang liji ( material physics and chemistry ) directed by professor xie xiaoming this paper is intended to solve problems for those who are designing , using pbgas . failure mechanism , as well as cycles to failure of two groups of pbga samples ( with / without underfill ) for thermal cycling conditions in the range of - 40 ~ 125 , were presented . the experiment shows that solder ball in the samples without underfill cracked after 500 times cycle , no crack was found in the underfilled samples even after 2700 cycles 通过一系列的实验,得到以下实验结果: ?在本论文设定的温度循环条件下,未充胶pbga样品的热疲劳品寿命在500周左右,充胶样品的焊点寿命高于2700周; ?对于未充胶器件,中心距( dnp )是决定焊点应力、应变大小的最主要因素,裂纹总是从中心距较大处萌生并向中心处扩展; ?温度循环的过程中焊盘附近焊料组织明显粗化。 |
| 6. | Physics capability such as density , conduct and mechanics capability such as tensile strength , hardness and stretch ratio were tested during technical course . photograph analysis and empa analysis were carried out . the influence factor on materials physics and mechanics capability were investigated , which induced by powders synthesis technique , pressure and sinter temperature 在制备铜基复合材料的工艺过程中,对材料进行密度、电导率等物理性能和抗拉强度、布氏硬度、延伸率等力学性能的测试,进行金相分析和empa分析,研究了粉末合成工艺、压制压强、烧结温度等对材料物理、力学性能的影响,探索了材料密度、布氏硬度、电导率、抗拉强度、延伸率等之间的关系。 |
| 7. | Jiulin wang ( materials physics and chemistry ) directed by naixin xu , jun yang and jingying xie due to its abundant resources , low toxicity and the highest charge capacity in all known cathode materials , elemental sulfur is a promising cathode material for the next generation of high - performance lithium batteries 单质硫因具有很高的理论能量密度、丰富的自然资源和无毒性等多种优势,成为下一代锂电池中替代licoo _ 2的首选正极材料之一。可是目前报道的li / s电池面临着一系列严重的问题,包括活性物质利用率低,循环性能差等。 |
| 8. | The physical property of electron - phonon interaction systems is one of the fundamental problems in condensed matter theory . its development and perfection will profit the solving of some important problems in the areas of condensed matter physics , materials physics , protein molecular dynamics as well as other related subjects . so the study of the nonlinear lattice effects in electron - phonon interaction systems has been received extensive attention of many researches in the past years 电子-声子耦合系统的物理特性是凝聚态理论中的一个基本问题,它的发展和完善可能为凝聚态物理与材料物理领域及蛋白质分子生物学等交叉学科领域中一些重要问题的解决带来一定的启示甚至突破性的进展,因而近几年来电子-声子耦合系统中晶格非线性效应的研究受到人们的广泛关注。 |
| 9. | On the base of the study on sige material physics characteristic , sige / si hetero - junction characteristic , we dissertate the advantage of sige / si hetero - junction power diodes and establish more accurately physical models and propose two novel kinds of fast and soft recovery p + ( sige ) - n - - n + hetero - junction power diodes : the one is p + ( sige ) - n " - n + diode with the multiplayer gradual changing doping concentration in the n - region , and the other is p + ( sige ) - n " - n + diode with ideal ohmic contact on the cathode interface 本文针对sige材料的物理特性、 sige si异质结特性建立了准确的物理参数模型。在详细论述了sige si异质结功率二极管良好特性的基础上,提出了两种快速软恢复sige si功率二极管新结构: n ~ -区采用多层渐变掺杂和阴极侧采用理想欧姆接触。 |