Thermal mixing of two miscible fluids in a T-shaped microchannel

In this paper, thermal mixing characteristics of two miscible fluids in a T-shaped microchannel are investigated theoretically, experimentally, and numerically. Thermal mixing processes in a T-shaped microchannel are divided into two zones, consisting of a T-junction and a mixing channel. An analytical two-dimensional model was first built to describe the heat transfer processes in the mixing channel. In the experiments, de-ionized water was employed as the working fluid. Laser induced fluorescence method was used to measure the fluid temperature field in the microchannel. Different combinations of flow rate ratios were studied to investigate the thermal mixing characteristics in the microchannel. At the T-junction, thermal diffusion is found to be dominant in this area due to the striation in the temperature contours. In the mixing channel, heat transfer processes are found to be controlled by thermal diffusion and convection. Measured temperature profiles at the T-junction and mixing channel are compared with analytical model and numerical simulation, respectively.     

An integrated microfluidic cell array for apoptosis and proliferation analysis induction of breast cancer cells

In vitro sensitivity testing of tumor cells could rationalize and improve the choice of chemotherapy and hormone therapy. In this report, a microfluidic device made from poly(dimethylsiloxane) and glass was developed for an assay of drug induced cytotoxicity. We evaluated the apoptotic and proliferation-inhibitory effects of anticancer drugs mitomycin C (MMC) and tamoxifen (TAM) using MCF-7 breast cancer cells. MMC and TAM both induced apoptosis and inhibited proliferation of MCF-7 cells in a concentration-dependent manner. MMC caused the expression of antiapoptotic protein Bcl-2 a dose-dependent reduction in MCF-7 cells. The expression of Bcl-2 did not change significantly in MCF-7 cells treated by TAM. The results in the microfluidic device were correlated well with the data obtained from the parallel experiments carried out in the conventional culture plates. The developed microfluidic device could be a potential useful tool for high content screening and high throughput screening research.     

基于Opnet仿真的校园网性能分析与研究

早期建成的校园网,受当时资金和技术条件限制,节点少,带宽低,运行业务简单。随着学校规模的不断扩大,需入网的节点以及使多媒体等业务的需求迅速增长,许多早期建成的校园网因无法满足日益增长的应用需求,进行了重新规划设计。文章利用仿真软件OPNET对原有校园网进行性能分析,找出问题,并对新的设计方案可行性进行评估预测。故具有一定的工程应用价值     

一种全软开关的升压变换拓扑电路

针对SIC二级管的电压电流耐量都比较小,难以在大功率场合得到应用,本文介绍一种大功率的功率因数校正电路,实现电路的高频高效运行,大大减小EMI。     

新建本科院校提高《马克思主义基本原理概论》课教学实效性的思考

思想政治理论课“05”新方案要求在本科院校开设《马克思主义基本原理概论》课程。作为新建本科院校,如何有效实施“05”课程新方案,加强思想政治理论课教学,切实提高《马克思主义基本原理概论》课程的教学水平和教学实效性,是我们每一位从事这门课程教学的教师应该思考的问题。     

深化院系两级管理 提高教学管理水平——以沈阳理工大学应用技术学院教学管理实践为例

实施院系两级管理是教学管理制度改革的重要举措,对提高我院教学管理的科学化、高效化,对于推进＂特色兴校＂战略具有重要意义。沈阳理工大学应用技术学院在教学工作实际中,开展院系两级管理的探索：制定了院系两级管理的原则;提出了进一步深化两级管理的具体措施;并强调了在实施院系两级管理的过程中应解决好一系列问题。这一管理模式能够有效地促进教学管理水平的提高。     

职业学校开展创业教育的因由分析及对策

职业学校实施创业教育是适应我国经济发展的必然趋势,加强创业教育是促进现代职业教育发展的关键。本文着重分析了职业学校开展创业教育的必要性。以及职业学校开展创业教育的措施与途径。     

青海省杂多县-洼里涌地区超基性岩地球化学特征、时代及构造环境研究

青海省杂多县-洼里涌地区位于青藏高原腹地的唐古拉山北坡,龙木错—双湖缝合带以北,可可西里—金沙江缝合带以南的北羌塘昌都陆块,区内脉岩岩石类型主要有超基性—基性岩脉和中—酸性岩脉,其中中酸性岩脉最为发育且分布最广,且与区内的金、铜等矿化有着密不可分的关系,超基性、基性岩脉不发育,矿化较少,但对其时代及地球化学特征的研究与区内成矿作用及地质环境研究也具有重要的意义。本文通过对测区岩石化学测试、稀土元素测试、微量元素测试、同位素测试后,经综合分析,得出基性岩的岩石类型为钙碱性岩,构造环境应属测区华力西期晚期阶段伸展环境,时代为晚二叠世。     

彭州市新兴镇新型农村合作医疗现状及居民对“先看病后付费”制度认知度的调查与分析

目的：了解彭州市新型农村合作医疗现状及乡镇居民对“先看病后付费”制度的认知度,分析存在的问题及相关的影响因素,并为制定具有针对性的干预措施提供科学依据。方法：采用抽样调查的方法,自行设计问卷,对彭州市新兴镇8个村和一个社区的乡镇居民进行问卷调查。结果：92.68%的乡镇居民参加了新型农村合作医疗,低于全国新农合覆盖率,80.8%的乡镇居民清楚新型农村合作医疗制度,但对“新农合”满意的仅占67.07%,仅有53.50%的乡镇居民认为参加“新农合”后医疗保障水平有提高。对“先看病后付费”制度的知晓度仅有45.7%,认为全面推行“先看病后付费”制度可行的占70.1%。结论：虽然乡镇医疗卫生事业随着各种相关政策的出台,已有了很大的改观,但新型农村合作医疗制度仍然存在很多问题,需要不断完善新农合制度后,才能更好的推行“先看病后付费”制度,提高农村社会保障水平。     

恩施烟花爆竹仓库安防监控系统防雷设计

本文经过现场勘测,按照相关的依据和原则,对恩施烟花爆竹仓库安防监控系统进行了全面系统的雷电防护方案设计,主要考虑了监控系统的前端部分的雷电防护、传输线路的雷电防护、各监控中心终端设备过电压保护盒室外监控摄像机的接地。目的是为了通过全方位防护、综合治理、层层设防,力争将雷电对监控系统产生的危害降低到最低点。