纳米材料对PBT合成的催化性能研究

用溶胶－凝胶法制备TiO2及TiO2/SiO2复合纳米材料，作为PBT（聚对苯二甲酸丁二酯）合成的催化剂，与现在普通使用的催化剂钛酸丁酯进行了比较和研究。结果发现，TiO2/SiO2复合纳米材料催化性能最好，纳米TiO2次之。     

Adsorption of 117mSn(Ⅳ)-EDTMP on hydroxyapatite and collagen

Some organic phosphines labeled with 117mSn(Ⅳ) have been provedpromising for imaging and pain palliation of bone tumor. In this paper, a prelimi-nary investigation on the adsorption characteristics of EDTMP (ethelenediaminete-tramethylene phosphoric acid) labeled with 117mSn(Ⅳ) on HA(hydroxyapatite) andcollagen, and an investigation on the adsorption mechanism of 117mSn(Ⅳ)-EDTMPon HA was presented.``     

Association of angiotensin-converting enzyme gene I/D polymorphism with change in left ventricular mass in response to physical training

PURPOSE: To determine the radiologic characteristics of cystic dystrophy of the duodenal wall. MATERIALS AND METHODS: Ten patients with cystic dystrophy of the duodenal wall and chronic pancreatitis underwent ultrasonography (US) (n = 10), computed tomography (CT) (n = 10), endoscopic US (n = 5), and endoscopic retrograde cholangiopancreatography (ERCP) (n = 9). Cystic dystrophy of the duodenal wall was classified as either cystic or solid. The imaging findings were retrospectively analyzed and compared with findings at pancreatoduodenectomy (n = 10). RESULTS: The more frequent cystic type (n = 7) of cystic dystrophy of the duodenal wall was characterized by the presence of easily recognizable cystic lesions (diameter, more than 1 cm), located within the thickened wall of the second portion of the duodenum. The solid type (n = 3) of cystic dystrophy of the duodenal wall demonstrated fibrous thickening of the duodenal wall within which small cysts (diameter, less than 1 cm) were present. The intraduodenal cysts were usually elongated or bilobate with a thick wall. The thickening of the duodenal wall appeared as a solid layer between the duodenal lumen and the pancreas, hypoechoic at US, isoattenuating at unenhanced CT, and hypoattenuating in the early phase (after initiation of infusion of contrast material) and isoattenuating in the late phase (after completion of infusion) at contrast material-enhanced CT. Findings at retrospective analysis of CT and endoscopic US images were characteristic. CONCLUSION: Imaging modalities, notably CT and endoscopic US, helped establish the diagnosis of cystic dystrophy of the duodenal wall.     

Intrauterine transfusions influence fetal leukocyte counts and subsets

Histamine is an important mediator in allergic reactions, gastric acid secretions, and neurotransmission in the central nervous system. Basophils and mast cells are the main sources of histamine, which is formed from L-histidine by histidine decarboxylase (HDC). However, the regulatory mechanism of HDC in these cells remains unclear. We examined the regulation of HDC activity and gene expression using a unique human mast cell line, HMC-1, after stimulation with phorbol 12-myristate 13-acetate (PMA) or ionomycin. HDC activity was increased from 52.1+/-0.4 (mean+/-standard deviation) to 154+/-6.9, or 105.6+/-6.2 pmol/min/mg protein (n = 3), 4 hours after stimulation with PMA (10 ng/mL) or ionomycin (10[-6] M). Although actinomycin D had no effect on this increase, cycloheximide completely inhibited the increase caused by these stimuli. The population of HMC-1 cells containing HDC protein was increased after stimulation with either PMA or ionomycin as evaluated by immunocytochemical analysis with anti-HDC antibody as a marker. HMC-1 constitutively expressed HDC mRNA, and its level was not increased with these stimuli. These results suggest that the increase of HDC activity in HMC-1 induced by PMA or ionomycin is regulated at the translational level.     

石油钻机提升系统穿绳方法研究

目前国内外钻机大绳一般采用顺穿法或花穿法。分析了2种穿绳方法的受力特点,大绳顺穿时游车的受力不平衡,会发生倾斜和摆动;采用大绳花穿方法,避免了游车的倾斜和摆动,但造成大绳入轮槽的倾角大,大绳易脱槽。顺穿法一般在电动钻机上采用,主要考虑到电控操作提升系统比较平稳;花穿法一般在机械钻机上使用,以受力平衡来缓解气控操作带来的冲击载荷的影响。为了克服这2种穿绳方法的不足,提出了两行双联滑轮组顺穿法和双联滑轮组顺穿法,可以提高安全性,减少磨损。     

可追溯的绿色安全猪肉生产系统研究

现在，养猪生产者滥用激素、微量元素和违禁药物饲养生猪，而消费者却无法识别这种猪肉，严重地威胁着消费者的食品卫生安全。为此，应用射频识别技术，采用综合软件管理，以一维条形码实行三网合一查验的方式来建立猪肉生产卫生安全跟踪系统，是保障消费者食品卫生安全的理想方法。     

多时滞Lotka-Volterra互惠系统周期正解的存在性

用重合度理论研究具时滞非自治Lotka-Volterra互惠系统，获得了周期正解的存在性，推广了Gopalsamy及He(1997)的结果。     

ZnS掺杂技术研究及应用现状

对现阶段国内外在ZnS及ZnS基材料掺杂改性方面的研究成果作一概述性介绍，综述了纳米级ZnS发光材料掺杂改性的基本机理，主要的掺杂技术、方法，并对多种掺杂元素的效果进行了分析比较。     

吸收雷达波包装材料的研究进展

论述了吸收雷达波包装材料的基本组成及其选择原则，在此基础上讨论了吸波材料的吸波原理及影响吸波性能的因素，并指出了吸波包装材料的开发现状和应用进展及其发展万向。     

新型微波-毫米波幅相测试系统及扩展应用

介绍了一种新型微波 毫米波幅相测试系统及其在相关测试领域中的典型应用。与传统微波幅相测试系统相比 ,该系统具有原理新颖、结构简单、扩展频段容易和使用方便等优点。本系统目前广泛应用于紧缩场电气性能检测、天线测量和RCS测量等领域中 ,频率范围为 1～ 110GHz。本测试系统已经申请国家专利 ,并通过相关部门鉴定。