氢氧化镁对废水中镉(Ⅱ)吸附性能的研究

采用氢氧化镁对含镉废水进行处理．实验考察了氢氧化镁用量、搅拌时间、温度及pH对处理效果的影响，探讨了吸附作用机理．结果表明：氢氧化镁对镉(Ⅱ)离子具有较强的吸附性能，去除率可达99％以上．氢氧化镁吸附镉(Ⅱ)离子的最初速率与浓度成一级反应，在镉(Ⅱ)离子浓度低于80mg／L时，吸附等温线符合Langrnuir模式，饱和吸附量为26．02mg／g．     

材料稳态蠕变模拟的无网格伽辽金法研究

无网格法是近年来迅速兴起的一种很有发展前途的数值分析方法，它可以克服有限元法等传统的数值方法对网格的依赖性，彻底或部分的消除网格，是目前国内外力学界的热点研究领域之一。由于网格的存在，有限元法在处理涉及网格畸变和自适应等计算时，如在裂纹扩展、冲压成型问题中遇到很多的困难，通常采用更新网格或网格重构来解决问题，这样不仅浪费了计算时间，     

CLONING AND EXPRESSION OF A GENE MEDIATING γ-RADIATION-INDUCED APOPTOSIS IN HL-60 CELLS

Apoptosis,orprogrammedcelldeath(PCD),isanintricatelyregulatedprocess">.Geneticstud-iesofapoptosisinCaenorhabditiseleganshavei-dentifiedced-3andced-4asproapoptoticgenesandced-9asanantiapoptoticgene"=-Severalmam-malianhomologuesofced-3,ced-4andced-9havebeenidentified.Recentstudiesindicatethatthefundamentalapoptosismachinery,whichconsistsofdistincteffectors,inhibitorsandinitiators,hasbeenconservedthroughoutevolution.Thekeyapoptosiseffectorsinmammalsareafamilyofcys-teine-containing,aspartate-spe…     

PROLIFERATION AND MIGRATION OF EPENDYMAL CELLS IN THE BRAIN OF ADULT RATS AFTER PERMANENT FOCAL CEREBRAL ISCHEMIA

Objective Ependymal cells are thought to be the primary source of neural stem cells in the adult central nervous system. The purpose of this study is to examine spatial and temporal profiles of ependymal cell proliferation and migration after focal cerebral ischemia. Methods Eighty male Sprague Dawley rats underwent permanent middle cerebral artery occlusion after injection of 10/μL of 0.2% Dil into the lateral ventricle. Rats were sacrificed and brain sections were acquired for pathological evaluation and laser confocal imaging at day 1,3,7,11,14,21 and 28 after ischemia. Results The density of Dil-labeled cells in the ischemic ipsilateral subventricular zone was significantly higher than that in the control group and these labeled cells dispersed in the ischemic ipsilateral subventricular zone and/or were located in ependyma from day 1 to 11. In the ischemic ipsilateral cortex, some Diilabeled cells occurred in peri-infarction and infarction of parietal region at day14 and peaked at day 21 when some Dil-labeled cell nodules were found in this region. During postischemic day 14--28, a significant decrease in labeled celldensity in the ischemic ipsilateral subventricular zone was coincident with a significant increase in labeled cells density in the cortex (peri-infarction and infarction). Conclusion The results indicate that ependymal cells proliferate and migrate after focal cerebral ischemia in the adult rat brain.     

Study of the mechanism on the apoptosis induced in Human leukemia cell line K562 by the combination of indole-3-acetic acid and horseradish peroxidase

Objective To investigate the mechanisms of apoptosis induced in Human leukemia cell line K562 by the combination of indole-3-acetic acid and horseradish peroxidase. Methods Human leukemia cell line K562 were exposed to indole-3-acetic acid （IAA） at 20, 40, 60, 80 or 100 mol/L and horseradish peroxidase（HRP） at 1.2 g/mL for varying times. MTT assay was applied to detect the cell proliferation. Flow cytometry was performed to detect the arrest of cell cycle. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） assay was used to measure apoptosis. 2, 7-dichlorofluorescin diacetate （DCFH-DA） uptake was measured to determine free radical by confocal microscope. Content of malondiadehyde （MDA） and activity of superoxide dismutase （SOD） were measured by biochemical methods. Results IAA/HRP initiated growth inhibition of K562 cells in a dose- and time-dependent manner. Flow cytometry revealed that cell cycle arrested at G1/G0 after 24 hours treatment. After 72 hours treatment, apoptotic rate of 100 mol/L IAA group increased to 43.9 %, which was 5 times that of control（P〈0.01）. Content of MDA and activity of SOD increased respectively in treatments compared with control. Meanwhile, IAA/HRP stimulated the formation of free radical, which was increased by IAA concentration-dependently. Conclusion The combination of IAAand HRP can inhibit the growth of Human leukemia cell line K562 in vitro by inducing apoptosis which is associated with the increase of free radical. The combination of IAA and HRP might be a promising chemopreventive and chemotherapeutic agent against human leukemia.     

教你画汽车

你喜欢神来之笔的汽车设计吗?你梦想像汽车设计师那样挥洒创意吗?是否苦于没有学过绘画而画不好或者无从下笔?不要发愁.本文介绍的几个步骤可以帮你尽快入门,熟加练习后你就可以交出一份像样的作品了! Let's go……     

酒精诱导的小鼠生殖系统损伤与一氧化氮的关系

目的　研究酒精饲养小鼠精子死亡率和活动率与睾丸一氧化氮 (NO)形成的关系。方法　应用灌胃的方法饲养酒精组小鼠 ,并检测小鼠精子死亡率、活动率以及睾丸NO含量和NOS活性。结果　酒精饲养小鼠精子死亡率明显高于对照组 ,而活动率以及NO含量和NOS活性均低于对照组。结论　酒精诱导小鼠精子质量下降与NO浓度有关     

叠合框架受力性能的试验研究

对两榀两跨两层叠合框架试件（ＫＪ１，ＫＪ２）和一榀条件基本相同的整浇框架（ＫＪ３）进行了试验，用对比试验研究的方法，研究了叠合框架二次受力特性，证实了叠合框架梁的正弯矩钢筋“应力超前”，叠合层压区混凝土“应变滞后”的特性仍然存在。试验证明，同基本条件的前提下，叠合框架的承载力不会低于整浇框架。进而探讨了叠合框架的传力机构，提出了保证叠合框架节点整体性的构造措施。     

道路三维场景的实时动态显示技术

实时动态显示技术是实现道路三维可视化设计的关键，应用Delaunay三角化算法构建数字地面模型，基于分割—归并思想完成道路三维实体造型，在此基础上，提出并实现了有效的道路三维模型的视相关简化算法，并结合真实感图形绘制技术开发了道路三维场景的实时动态浏览平台，将该平台与路线CAD系统集成，实现了道路设计过程和设计成果的可视化。