40 research outputs found

    在化学教学中培养学生自主学习的能力

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    培养学生自主学习的能力是课程改革的重要目标,是素质教育的要求.也是促使学生形成终身学习的能力和可持续发展的需要.本文提出了在化学教学中培养学生自主学习能力的一些教学策略:创设教学情境,激发学生自主学习的兴趣;发挥实验功能,培养学生自主学习的精神;指导课外阅读,培养学生自主学习的习惯;开展研究性学习,提高学生自主学习的能力;运用多媒体信息技术,推动学生自主学习;开展社会实践活动,使学生的自主学习能力得到升华

    高中化学“实验设计与科学探究”课程资源的开发与利用

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    实验既是化学学科发展的基础,又是化学教学的有效手段,以实验为基础创造出便于学生探究的教学情景,进行化学“实验设计与科学探究“课程的资源开发与利用显得尤为重要.如何利用好实验课程资源实现基于实验的教学设计,在理念、思维和操作层面的发展是我们要探讨的课题

    周期性机械拉伸对表皮干细胞分化及生物学效应的影响

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    背景:表皮干细胞是创面愈合过程中的重要细胞成分之一,表皮干细胞分布在基底层,约占基底层细胞的1%-10%,对皮肤的张力有较高的感应能力,其细胞表面有高水平的integrin-beta1表达,因而integrin-beta1高表达被认为是KSC分子标志之一,同时也是表皮干细胞对皮肤张力的感应器。。整合素尤其是整

    Tb_3Al_5O_(12)∶Ce~(3+)发光粉的微波辅助合成和性能表征

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    采用微波辅助合成-高温热处理制备了铈掺杂铽铝石榴石(Tb3Al5O12∶Ce3+,简称TAG∶Ce)发光粉。用XRD、SEM、激发和发射光谱等对粉末的晶型、形貌以及发光性能进行了表征。结果表明,发光粉晶粒清晰、表面光滑,粒径在2μm以下。TAG∶Ce的激发光谱主激发峰在467nm,330nm左右存在次激发峰,375nm附近存在两个强度较弱的峰;发射光谱峰值波长为550nm,与传统固相法制备的TAG∶Ce基本一致。与传统高温固相反应法相比,此方法具有高效、节能、环保等优点。通过分析反应历程,证明了Tb2O3-Al2O3系统中Al离子的分扩散系数大于Tb离子的

    The Development of a New Type of Medical Rehabilitation Brace for Lower Limbs

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    本文阐述了一种新型医用下肢康复支具的研制过程。该装置主要由承重装置、负重装置、负重调节装置以及压力检测装置等结构组成,具有调节、设定以及控制负重载荷等功能,可使行内固定术后的下肢骨折患者早期进行负重、行走功能锻炼,促进其骨折愈合及肢体功能康复,减少术后并发症,具有一定的实用价值。The paper expounded the development of a new type of medical rehabilitation brace for lower limbs. The device was mainly composed of different structures including the hip weight-bearing device, the foot weight-bearing device, the weight-bearing adjustment device and the pressure detection device. The brace was designed to allow patients to carry out weight-bearing exercises and walking exercises in early postoperative period after receiving internal fixation of lower limb fracture. It could also promote fracture healing and functional recovery of lower limbs and reduce postoperative complications, which is of certain clinical value

    In Situ FTIR Spectrocopic Investigations of 1,3-Butanediol Oxi dation on Sb and S Modified Pt Electrodes

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    运用电化学原位FTIR反射光谱研究了 1,3丁二醇在以Sb和S修饰的Pt电极上的氧化过程。结果表明Sb和S修饰都能抑制 1,3丁醇的解离吸附。红外数据指出Sb的存在使 1,3丁二醇氧化产物同时含有羰基物种和CO2 ,而S修饰的Pt电极上以羧酸物种为主。In the present paper,we studied the surface st ru cture effect of Pt electrode modified with antimony and sulfur adatoms towards 1 ,3-Butanediol oxidation.The results demonstrated that the modification of Sb an d S both inhibited the dissociative adsorption of 1,3-Butanediol into CO,which is the main source of self-poisoning in electrocatalysis of small organic molec ules.At lower potentials,the principal oxidation pathway of 1,3-Butanediol on P t/Sb ad electrode is towards the production of C=O.However,at higher potent ials,the products of CO 2 increased.The presence of S ad inhibited the ox idation of 1,3-BD at low potentials(0 8 V).国家自然基金!(2 99730 35)资

    凝胶推进剂模拟液静电雾化行为规律研究

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    针对凝胶推进剂雾化困难的问题,引入静电喷射技术雾化凝胶推进剂。以水凝胶模拟液为介质,探究静电雾化技术的可行性及试验条件,当收集距离2~5 cm、供液速率10~30μL/h时,凝胶模拟液可实现稳定雾化,收集液滴直径小于100μm,散射角分布在8°~36°之间,收集液滴直径和散射角均随收集距离的增大和针管直径的减小而减小;同样条件下,凝胶粘度越小,散射角和雾化液滴直径越小。在此基础上,针对单针管推力小的问题,分析使用多针管喷头进行凝胶推进剂静电雾化的可行性及其雾化区域分布,结果表明2号凝胶模拟液用于多喷头雾化可得到良好的雾化区域分布,适用于凝胶推进系统之中。国防科技重点实验室基金项目(61427040203162704004

    抗戊型肝炎病毒单克隆抗体识别表位的初步研究

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    通过Western blot、体外捕获PCR、ELISA阻断实验及合成的多肽库等方法,对23株抗戊型肝炎病毒(HEV)单克隆抗体(单抗)识别HEV ORF2表位的作用进行系统研究。结果显示,7株线性单抗识别表位都位于ORF2 aa408~458之间,16株构象型单抗识别表位都定位于ORF2 aa459~606之间,大部分构象型单抗识别表位都在天然病毒表面。对这些单抗识别表位系统地了解将为HEV疫苗、诊断、病毒受体和病毒感染机制等方面的研究提供重要工具

    In situ FTIR spectrocopic investigations of 1,3-butanediol oxidation on Sb and S modified Pt electrodes

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    In the present paper,we studied the surface structure effect of Pt electrode modified with antimony and sulfur adatoms towards 1,3-Butanediol oxidation. The results demonstrated that the modification of Sb and S both inhibited the dissociative adsorption of 1,3-Butanediol into CO, which is the main source of self-poisoning in electrocatalysis of snail organic molecules. At lower potentials,the principal oxidation pathway of 1,3-Butanediol on Pt/Sb-ad electrode is towards the production of C = O. However,at higher potentials,the products of CO2 increased. The presence of S-ad inhibited the oxidation of 1,3-BD at low potentials(0.8 V)
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