The maxim of Tsinghua University and the education of universal geniuses

【中文文摘】当年清华国学研究院的梁启超先生提出以“自强不息 ,厚德载物”作为清华校训。从此 ,这一校训激励了一代又一代清华人自强不息 ,朝着品学兼优的方向发展。在“通识为本 ,专识为末”的通才教育思想指导下 ,清华为国家造就了一大批栋梁之才。今天我们通过对清华校训及清华教育宗旨的进一步领悟 ,来探讨通才教育的真谛 ,探讨今天大学及大学教育的真正意义 ,无疑有助于我们搞好高等教育事业 【英文文摘】Mr.Liang Qi-chao from National Affairs Research Institute,Tsinghua University once put forward the maxim of Tsinghua:Make unremitting efforts to improve oneself,Improve one′s morality to build the country.From then on,this maxim has been inspiring generations of Tsinghua students to strive constantly to be excellent both morally and academically.Under the guidance of the thought of universal geniuses education:Universal knowledge is basic,specialized knowledge next.Tsinghua has trained a large number of graduates who turned to be the pillars of the state. Now , through the understanding of the maxim of Tsinghua ,we are probing into the truth of universal geniuses education ,higher education and the significance of higher education ,which will undoubtedly improve higher education

Investigation of behaviour of particle impact on material by impinging jet

颗粒冲击材料现象广泛存在于自然界以及工业领域中。应用实验测量与数值计算相结合的方法研究了颗粒射流冲击材料(304不锈钢)的磨损行为。考虑了颗粒粒; 径、运动轨迹、颗粒-壁面撞击点分布以及所导致材料物相结构变化。实验测试包括材料质量损耗、材料元素X射线衍射(XRD)分析、表面微观结构扫描电镜(; SEM)观察。对相应的颗粒射流冲击材料行为进行了数值计算,获得流场,颗粒场以及相应材料磨损。结果表明:颗粒射流冲击下颗粒运动轨迹与撞击点的分布不; 同,造成了材料样品表面磨损区域明显不同。颗粒-壁面碰撞不仅会导致材料损失而且会造成材料物相结构的变化。Particle-material impact is popular in the nature and industries. In; this work, experimental measurement and numerical calculation were; carried out to investigate the particle impinging jet effect on the; behaviour of material (304 stainless steel). Herein, particle diameter,; particle tracking trajectories, particle-wall collision point; distribution were considered to study material loss and the phase change; of material structure. In the experimental work, the measurements were; carried out for material mass loss, material element X-ray; diffractometry (XRD) analysis, surface micro-structure scanning electron; microscopy (SEM) observation and so on. In addition, the behaviour of; particle impinging jet impact on wall material was studied by numerical; simulations. Particularly, flow fields, particle trajectories and wall; material loss were obtained. The results show that particle collision; point distribution is quite different from their tracking trajectories; under particle impinging jet impact, which causes the wear zones on; sample surface different from each other obviously. It is concluded that; particle-wall impact will not only lead to material loss but also cause; the phase change of material structure.国家自然科学基

氧化石墨烯改性高温环氧树脂基碳纤维复合材料的热性能与力学性能

采用湿法预浸技术和模压工艺,制备了氧化石墨烯(GO)改性碳纤维/环氧树脂(CF/E54-DDS)混杂复合材料,利用差示扫描量热分析(DSC)、动态热机械分析(DMTA)、无损C扫描等开展了GO对复合材料的热固化性能、凝胶工艺性、动态热机械性能以及抗冲击损伤性能等的影响研究。结果表明,GO结构中的羟基、羧基会促进改性树脂体系的固化反应,GO/E54-DDS的固化反应比E54-DDS的提前,反应变得和缓,且会加速固化反应的进行;在GO含量小于0.5%时,GO的活性基团可增加改性体系的交联密度而提高复合材料的玻璃化转变温度,但GO含量大于0.8%时,会因DDS在固化网络结构中的占比下降较大,反而降低复合材料的玻璃化转变温度;GO/CF/E54-DDS预浸料比CF/E54-DDS表现出更好的浸润效果;CF/E54-DDS复合材料破坏后碳纤维表面光洁,破坏主要发生在碳纤维与树脂基体的界面,而GO/CF/E54-DDS复合材料破坏后,碳纤维表面紧密粘附着GO/E54-DDS固化物,破坏主要发生在碳纤维织物层间的GO/E54-DDS区域;GO的存在提高了GO/CF/E54-DDS复合材料抵抗横向裂纹和纵向裂纹扩展的能力,复合材料的损伤投影面积和凹坑深度减小,提高了冲击后压缩强度。航空科学基金(2016ZF68011);;福建省科技创新平台建设计划(2014H2006);;福建省自然科学基金(2015J01222);;厦门大学石墨烯工业技术研究院资助项目(2014I2005

Screening Antitumor Effect of Active Constituents from Portulaca oleracea L. in vitro and in vivo

目的观察马齿苋活性成分对人肺腺癌细胞系(A-549 CEll)、人喉表皮样癌细胞系(HEP-2 CEll)、人宫颈癌细胞系(HElA CEll)和人恶性胚胎横纹肌瘤细胞系(rd CEll)生长的影响。方法体外培养条件下用不同浓度的马齿苋活性成分处理4种癌细胞,通过溴化二甲噻唑二苯四氮唑(MTT)试验法测定癌细胞的增殖;同时处理S180荷瘤小鼠,观察荷瘤小鼠的体重、瘤重、死亡率和抑瘤率。结果马齿苋生物碱对离体培养的A-549肺癌细胞、HElA细胞和HEP-2细胞的增殖均具有明显抑制作用,马齿苋多糖对HElA细胞有较强的抑制作用,马齿苋脂肪酸对HEP-2细胞有一定的抑制作用,马齿苋黄酮对rd细胞有很强的抑制作用,并存在浓度剂量效应,高浓度抑制作用强。结论马齿苋活性成分能选择性地杀伤癌细胞,有进一步研究的潜在价值。Objective To observe the effects of the active constituents from Portulaca oleracea L.on the proliferation of four human tumor cell lines.Methods The anti-proliferation activities of active constituents from Portulaca oleracea L.upon A549 cell,Hela cells,Hep-2 cell and RD cell were analyzed by MTT in vitro.Body weigt,tumor weigt,inhibition rate and death rate of these active constituents from Portulaca oleracea L.on the transplanted tumor cells of Sarcinoma 180 were observed in mice.Results Raw screening of the four compounds by MTT indicated polysaccharides,flavonoids,alkaloids and polyunsaturated fatty acid exerted obvious suppression on the proliferation of tumor cell lines in a dose dependent manner,respectively.The experiments in vivo indicated that the four active constituents had certain inhibition against the cells of implanted tumor ascites Sarcinoma 180.Conclusion The active constituents from Portulaca oleracea L.have selective cytotoxicity to the tumor cells and is worthy of further investigation.江西省教育厅科技项目(No.〔2007〕285);江西科技师范学院大学生创业科研训练项目(No.[2007]-178

氧化石墨烯改性不同表面性质的碳纤维/环氧树脂的微观形貌与动态热力学性能

通过模压成型，用氧化石墨烯（GO）对四种碳纤维（CF）（CCF300、T700、CCF800、CCM40J）织物增强环氧树脂（EP）复合材料进行改性，通过材料的微观形貌、动态热力学性能等研究了GO对这四种不同表面性质的CF/EP复合材料的改性效果。研究表明，添加GO后，GO-EP对四种CF的浸润性均比EP明显提高，纤维与GO/EP间的界面黏接比与EP基体间的黏接明显改善；CF/EP复合材料的破坏主要发生在CF与EP的界面，而GO的存在使GO-CF/EP复合材料的破坏由CF与EP基体的界面向GO/EP区域过渡。CF的表面氧碳比和沟槽均会显著影响复合材料的玻璃化转变温度(Tg)，CF中具有最高表面氧碳比的GO-CCF300/EP表现出最高的Tg，但沟槽更丰富的CCM40J和CCF300对CF/EP复合材料的Tg表现出更好的GO改性效果。航空科学基金(2016ZF68011)福建省科技创新平台建设计划(2014H2006)厦门大学石墨烯工业技术研究院资助项目(2014I2005

高显色指数LED光谱配比与色度参数的关系

为了提高LED光源的显色性一般需要改变不同的荧光粉成分,理论上利用不同峰值的荧光粉配比可以实现类似的色温和显色指数。我们采用典型的蓝光LED、3种不同峰值波长的绿色/黄绿色荧光材料与典型红色荧光材料进行5种基本光谱的组合,对每种组合的色度学参数包括色坐标、相关色温、显色指数等进行了仿真计算,并对相近色温下的技术方案和显色性的关系进行了统计和分析。结果表明,在这一技术方案下色温和显色指数在可以较好地确定白光LED光谱的整体形态,同时更高的显色指数可以更好地约束所能采用的配比。国家重点研发计划(批准号:2017YFB0403705

第十八届美国理论与应用力学大会总结

1会议概况2018年6月5—9日,第18届美国理论与应用力学大会(18th U.S. National Congress of Theoretical and Applied Mechanics, USNCTAM2018)在美国芝加哥召开.本次大会由美国力学国家委员会和中国力学学会联合主办,旨在探讨和交流近四年世界范围内在理论和应用力学领域的基础研究、创新技术的最新进展,吸引了来自世界各地的近千名专家学

类泛素蛋白及其中文命名

泛素家族包括泛素及类泛素蛋白,约20种成员蛋白.近年来,泛素家族领域取得了迅猛发展,并已与生物学及医学研究的各个领域相互交叉.泛素家族介导的蛋白质降解和细胞自噬机制的发现分别于2004和2016年获得诺贝尔奖.但是,类泛素蛋白并没有统一规范的中文译名. 2018年4月9日在苏州召开的《泛素家族介导的蛋白质降解和细胞自噬》专著的编委会上,部分作者讨论了类泛素蛋白的中文命名问题,并在随后的\"泛素家族、自噬与疾病\"(Ubiquitinfamily,autophagy anddiseases)苏州会议上提出了类泛素蛋白中文翻译草案,此草案在参加该会议的国内学者及海外华人学者间取得了高度共识.冷泉港亚洲\"泛素家族、自噬与疾病\"苏州会议是由美国冷泉港实验室主办、两年一度、面向全球的英文会议.该会议在海内外华人学者中具有广泛影响,因此,参会华人学者的意见具有一定的代表性.本文介绍了10个类别的类泛素蛋白的中文命名,系统总结了它们的结构特点,并比较了参与各种类泛素化修饰的酶和它们的生物学功能.文章由45名从事该领域研究的专家合作撰写,其中包括中国工程院院士1名,相关学者4名,长江学者3名,国家杰出青年科学基金获得者18名和美国知名高校华人教授4名.他们绝大多数是参加编写即将由科学出版社出版的专著《泛素家族介导的蛋白质降解和细胞自噬》的专家

Microsphere Pattern Prepared by a "Reverse" Breath Figure Method

通讯作者地址: Xiong, XP (通讯作者), Xiamen Univ, Coll Mat, Dept Mat Sci & Engn, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Coll Mat, Dept Mat Sci & Engn, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] have reported all interesting method, named reverse breath figure, for the preparation of polymeric microsphere patterns. By the same procedure as breath figure, instead of under a humid atmosphere, linear and star-shaped poly(styrene-block-butadiene) copolymers dissolved in solvents such as toluene, trichloroform, and dichloromethane were cast onto the surface of a glass substrate in methanol or ethanol vapor. After the complete evaporation of the solvent, microspheres with the diameters ranging from hundreds of nanometers to several micrometers were prepared. The microsphere patterns are the reverse of the honeycomb porous structure of breath Figure. The mechanism of the microsphere formation has been studied to show that when the surface tension of the polymer solution is 1.5 mN/m higher than that of the condensed liquid, microsphere patterns call be prepared, whereas a honeycomb porous film of breath Figure call be obtained when the Surface tension of the polymer solution is lower than that of the condensed liquid. The viscosity of the polymer solution is also an important factor to influence the fabrication of the microsphere patterns.National Natural Science Foundation of China 2084400

改良分子信标-双重实时荧光PCR快速检测SARS病毒

目的建立改良分子信标-双重实时荧光PCR检测SARS病毒的方法,用于SARS的早期诊断和动物溯源。方法利用改良分子信标技术、装甲RNA和双片段双色荧光技术,根据GenBank公布的SARS病毒聚合酶基因1b的阅读开放框架结构的保守序列,自行设计一对引物和探针,以部分临床标本的酶联吸附实验结果和传统细胞培养方法作为对照,建立分子信标检测SARS病毒的方法。对368份临床标本(咽漱液、血液、粪便、尿液)、52份细胞培养液和50份动物标本进行荧光PCR扩增。结果分子信标检测SARS病毒的方法灵敏度为10～100个拷贝ml,与流感病毒等呼吸道病毒无交叉反应。分子信标检测368份临床标本,20份阳性。其中确诊病例阳性率为21.27%(1047),确诊病例的咽漱液阳性率为43.48%,还分别从粪便和血清中检测到SARS病毒。52份细胞培养液,29份阳性,阳性率为55.77%。50份动物标本,23份阳性,阳性率为46%。结论改良分子信标-双重实时荧光PCR检测SARS病毒方法灵敏度高、特异性强,可用于SARS的临床早期诊断和动物溯源