Fabrication of High Quality SiGe Virtual Substrates by Combining Misfit Strain and Point Defect Techniques

High quality strain-relaxed thin SiGe virtual substrates have been achieved by combining the misfit strain technique and the point defect technique.The point defects were first injected into the coherently strained SiGe layer through the "inserted Si layer" by argon ion implantation.After thermal annealing,an intermediate SiGe layer was grown with a strained Si cap layer.The inserted Si layer in the SiGe film serves as the source of the misfit strain and prevents the threading dislocations from propagating into the next epitaxial layer.A strained-Si/SiGe/inserted-Si/SiGe heterostructure was achieved with a threading dislocation density of 1×104cm-2 and a root mean square surface roughness of 0.87 nm.This combined method can effectively fabricate device-quality SiGe virtual substrates with a low threading dislocation density and a smooth surface.     

Effect of Fe(Ⅲ) impurity on the electrochemical performance of LiFePO_4 prepared by hydrothermal process

Lithium iron phosphate(LiFePO4)was synthesized from LiOH,FeSO4 and H3PO4 by a hydrothermal process at 180℃.The samples were characterized by X-ray diffraction,scanning electron microscopy and chemical analysis.Electrochemical performance of the samples was tested in terms of charge-discharge capacity and cycling behavior.The results indicated that Fe(Ⅲ) impurity had obviously effect on the electrochemical properties of LiFePO4,and the formation of Fe 3+ was caused by the oxidation of Fe 2+ in the dissolving...     

好氧微生物对三元采出水含油量去除效能分析

好氧微生物处理在三元复合驱采出水表现出较好的应用前景,在油田实际污水处理过程中,要求能够尽量的回收原油,减少微生物对水中剩余原油的降解.研究采用已驯化好氧生物载体填料,通过原水的室内试验,考察微生物降解石油过程中,将原油用于自身代谢底物和将原油回收的比率.研究表明,164.53 mg/L的采出水中原油,约12％的原油被微生物吸收利用,80％原油被回收,同时还有约5％～8％处理过程中被挥发和损耗;如果污水处理工艺中,采用气浮装置进行原油的回收,微生物将原油用于自身转化利用率为5％.结果表明在污水处理过程中,好氧微生物作为一种生物催化剂,其维持自身生存所利用的原油较少,而用于三元污水的深度处理上具有很好的处理效果.     

肿瘤相关性贫血的中西医研究进展

贫血是肿瘤患者常见的并发症,其发生率及严重程度与性别、年龄、肿瘤类型、分期、化放疗等有关.贫血可引起组织缺氧,使患者生活质量降低,是影响肿瘤患者生活质量的重要因素.贫血程度与化疗疗效、化疗药物的敏感性及耐药性密切相关.贫血患者常规化疗预后较差.低血红蛋白可使肿瘤组织放疗敏感性降低,是放疗患者预后差的独立预后因素.肿瘤相关性贫血的病因是多样的,包括肿瘤自身因素、治疗因素及营养因素等.促红细胞生成素(EPO)的使用是治疗肿瘤相关性贫血的主要方法,可以有效提高患者的血红蛋白水平,改善肿瘤患者的生活质量,提高肿瘤化放疗的疗效.随着中医对肿瘤相关性贫血认识的不断深入,中医药在肿瘤相关性贫血的治疗中取得了良好的疗效.     

δ~(13)C and water-use efficiency indicated by δ~(13)C of different plant functional groups on Changbai Mountains, Northeast China

Leaf δ13C of different plant functional groups (trees, shrubs and forbs; evergreen and deciduous; annual, biennial and perennial) were examined on the Changbai Mountains, China. Life form has a significant influence on plant δ13C, suggesting that leaf δ13C is also ideal for distinguishing functional groups species in temperate and frigid zones with high humidity. Additionally, the difference of water-use efficiency (WUE) is significant among different plant functional groups. δ13C and WUE are in the followi...     

设计2自由度控制器的新方法

提出了一种闭环辨识和2自由度控制器组结合的设计方法，从前馆控制器和反馈控制器两方面，根据预测误差，适当地选择辨识对象和加权函数，闭环辨识与控制器设计相结合，仿真结果证实，辨识容易，设计简单，方法有效。     

Effect of the silicon powder content on the properties of Al_2O_3-SiC-Me composites

By means of transient plastic phase process,the Al2O3-SiC-Me composites were produced throungh adding metal aluminium and silicon-powder to Al2O3-SiC materials.Under the condition of the same content of silicon and aluminium mixed-powder,the effect of silicon powder addition on properties of Al2O3-SiC-Me composites was studied by means of XRD and EPMA analyses in the temperature range of 300°C-1600°C.The results indicated that the content of metal phase in the sample at 1600°C increases with increasing silicon powder content.At the same time,when the temperature is lower than 1100°C,the strength of samples gradually increases with increasing temperature.However when the temperature is higher than 11000°C,the strength of samples gradually decreases with increasing temperature,and this change is very small.The results also indicated that at the same sintering temperature,the sample with 6%silicon powder has the maximum strength.     

基于精细碳黑模型的柴油机燃烧模拟

为更好地预测及分析柴油机污染物碳黑的产生特性,需要开发具有广泛应用价值的碳黑模型。该文以正庚烷作为燃料模拟物质,基于正庚烷氧化的气相反应机理,及描述固相碳黑颗粒形成物理、化学过程的详细动力学模型,对直喷式内燃机工作过程中的化学反应流进行了数值模拟计算。计算得到了柴油机燃烧室内多环芳烃质量、碳黑质量、体积分数随转角的变化曲线。在一定燃烧室壁面温度条件下,得到典型的多环芳烃质量、碳黑质量、碳黑体积分数均与测试水平相符,碳黑质量随转角变化曲线也与测试结果吻合较好。     

光纤制导与潜空导弹

概括分析了光纤制导技术的特点,综述了光纤制导技术的作战应用和国外正在开发研制的光纤导弹.概述了潜艇出海作战的主要空中威胁特点和国外现有的几种潜空导弹.综合比较表明,光纤制导的潜空导弹在作战性能和效费比上都是一种值得选择的发展途径.     

Three-dimensional Simulation and Pattern Making of Collar Using Geometric Model

An algorithm is presented for computationally simulating collars and drafting patterns. The collar shape was modeled by three-dimensional Bezier patch. Changing the position of control points of the patch can interactively control the collar shape. Using triangular surface developing method, patterns of various styles of stand collar and separating collar were drafted. As the subsystem of 3D apparel design system, an interactive collar design system is constructed. To inspect the practical usage, we reproduced the collars using these patterns drafted by the interactive collar design system. Comparing with simulated collars, the system demonstrated well and we found it is more reliable and accurate than the method of handwork.