Detecting the micro-defects in the GaAs materials by time resolved emissions

The GaAs material is a major semiconductor material, and it has high electron transfer rate and direct transition energy band structure. The devices and inte-grated circuits fabricated on the GaAs substrates have a lot of advantages such as high speed information processing. Small perturbations in the manufacturing of GaAs materi-als can lead to defects. The defects in the GaAs materials can degrade the performance of materials. A new method is presented in this paper for detecting the micro-defects in GaAs materials by using time resolved emissions. In this method, the micro-defects in GaAs materials are detected by making use of the photon emission features of micro- defects. The strength of the emitted photons from the micro-defects is increased by applying the electric current or the periodic pulse signals to GaAs materials. The single-photon detector is used to detect the photon emissions of the micro-defects. The time resolved photon emissions and single-photon detection are used to record and compare the amounts of the emitted photons that come from the given regions of the normal GaAs materials and the defective GaAs materials. A lot of experimental results show that the micro-defects in the GaAs materials can be detected by using the method proposed in this paper.     

Retrievals of atmospheric boundary layer temperature and moisture profiles by using Atmospheric Emitted Radiance Interferometer （AERI） measurements in Shouxian

The ground-based Atmospheric Emitted Radi- ance Interferometer （AERI） was deployed in Shouxian, China in 2008 to measure down-welling infrared radiances with high resolution. Based on AERI observations, we propose a new method for retrieving vertical temperature and water vapor profiles in the planetary boundary layer （PBL）. The method exclusively uses NCEP-2, a global reanalysis data as a first-guess profile in an iterative recursive algorithm. The PBL profiles of temperature and moisture under clear sky conditions in Shouxian have been retrieved using this new method. Compared with coinci- dent radiosonde measurements, we find that AERI is able to obtain more accurate temperature and water vapor pro- files in the PBL. The retrieval results with high temporal resolution can be used to monitor the PBL stability and evolution.     

一个关于{1,2,…,n}排列的猜想

我们证明了孙智伟的下述猜想:对任意不等于3的正整数n,存在{1,2,dots,n}的一个全排列(a1,…,an)使得a1＝1,an =n,并且a1 +a2,a2+a3,…,an-1 +an,an +a1都与n互素.     

金属离子负载树脂对水中氨氮的吸附特征

研究了金属离子负载树脂对水中氨氮的吸附特征.金属离子负载树脂对氨氮的吸附等温线表明,温度的升高有利于吸附,且吸附等温线都符合Langmuir模型.两种金属离子负载树脂对氨氮的吸附都符合准二级动力学方程.     

In vitro and in vivo studies on biodegradable magnesium alloy

The microstructure, mechanical property, electrochemical behavior and biocompatibility of magnesium alloy(Bio De MSM^TM) were studied in the present work. The experimental results demonstrated that grain refining induced by extrusion improves the alloy strength significantly from162 MPa for the as-cast alloy to 241 MPa for the as-extruded one. The anticorrosion properties of the as-extruded alloy also increased.Furthermore, the hemolysis ratio was decreased from 4.7% for the as-cast alloy to 2.9% for the as-extruded one, both below 5%. Bio De MSM^TMalloy shows good biocompatibility after being implanted into the dorsal muscle and the femoral shaft of the New Zealand rabbit, respectively, and there are no abnormalities after short-term implantation. In vivo observation indicated that the corrosion rate of this alloy varies with different implantation positions, with higher degradation rate in the femur than in the muscle.     

Joining of Si3N4 ceramic using PdCo(Ni SiB)–V system brazingfi ller alloy and interfacial reactions

The wettability of V-active PdCo-based alloys on Si3N4ceramic was studied with the sessile drop method. And the alloy of Pd50.0–Co33.7–Ni4.0–Si2.0–B0.7–V9.6(wt%),was developed for Si3N4ceramic joining in the present investigation. The rapidly-solidified brazing foils were fabricated by the alloy Pd50.0–Co33.7–Ni4.0–Si2.0–B0.7–V9.6. The average room-temperature three-point bend strength of the Si3N4/Si3N4joints brazed at 1453 K for 10 min was 205.6 MPa,and the newly developed braze gives joint strengths of 210.9 MPa,206.6 MPa and 80.2 MPa at high temperatures of 973 K,1073 K and 1173 K respectively. The interfacial reaction products in the Si3N4/Si3N4joint brazed at 1453 K for10 min were identified to be VN and Pd2Si by XRD analysis. Based on the XEDS analysis result,the residual brazing alloy existing at the central part of the joint was verified as Co-rich phases,in which the concentration of element Pd was high up to 18.0–19.1 at%. The mechanism of the interfacial reactions was discussed. Pd should be a good choice as useful alloying element in newer high-temperature braze candidates for the joining of Si-based ceramics.     

从神话叙事到神性写作——论1980年代以来小说叙事的话语谱系

当代小说叙事话语的代际嬗变始于启蒙叙事对十七年小说神话叙事的鼎力反拨,但启蒙叙事这一反神话叙事的话语方式,却逐步演化成了一种以道德神话为内核的新神话叙事。至上世纪90年代初,随着启蒙文学的暂时消歇,当代小说的叙事话语又转向了以欲望叙事为突出特征的世俗化叙事。此消彼长之下,世俗化叙事终以构筑身体神话的方式,取代之前的新神话叙事成为了当代小说的叙事主流。但在此历史进程中,启蒙叙事与世俗化叙事的话语博弈,又于90年代中后期催生出了神性写作这一新的小说叙事话语。从神话叙事到新神话叙事,再到世俗化叙事与神性写作,当代小说叙事话语的发展流变,已然自成系统地构建起了一个相对完整的知识谱系。     

新常态环渤海地区港口合作战略构想

随着中国进入重化工业化阶段,以及世界经济进入低迷期,环渤海地区在经济版图地位凸显,但同时,港口供给能力局部过剩严重,重复建设突出,合作必要性大大提高。今后,应该采取各项措施,调整环渤海地区港口竞合格局。在建立完善市场机制的基础上,政府应加强引导,从环渤海区域三大相对独立经济板块这一实际出发,结合区域内港口条件,设立"三层架构"的环渤海区域港口合作机制。     

具强噪声鲁棒性的聚类图像分割算法

针对已有的图像分割算法对噪声的鲁棒性不佳的问题,结合中智集合提出了一种新的基于中智集合聚类的图像分割算法,并为此聚类算法提出了高性能的目标函数.首先,将图像转换为中智集合域,然后定义一个高效的基于中智集合的聚类目标函数进行聚类分析,最终采用聚类算法将像素进行分类.将人工图像与真实图像进行对比试验.结果证明:本算法的有效性与分割准确率均高,同时具有较好的噪声鲁棒性.     

校企协同培养生物技术专业应用型人才的模式研究

随着我国生物产业的迅速发展,未来10年是我国生物技术人才事业发展的战略机遇期.如何以市场需求为指导,培养出"理论基础实、综合素质高、实践能力强、就业前景好"的生物技术专业应用型人才是我国普通高校急待解决的问题,而校企协同为高校人才培养提供了新的思路.从采取"走出去、请进来"战略、建立"基础-专业-实验"课程体系,构建校企合作"三模块"实习教学新模式,开设"企业班",培养"订单式"应用型人才,鼓励毕业论文"应用选题,真题真做",以"挑战杯"大赛为载体提高学生"创新创业"意识,构建生物技术专业"双师结构"教学团队,对当前形势下校企协同培养生物技术专业应用型人才的模式进行了新的探索.