Phase Segregation of ZnO/ZnMgO Superlattice Affected by Ⅱ-Ⅵ Ratio

在zn1-X Mg X O中,X=0.4~0.6仍为一个岩盐矿和纤锌矿共存的结构,影响了其晶格质量。本文利用等离子体辅助的分子束外延设备在C面蓝宝石衬底上外延生长了znO/znMgO超晶格,并改变其生长过程中的Ⅱ-Ⅵ比,利用原子力显微镜、X射线衍射、透射谱和X射线光电子能谱对样品进行了表征分析。发现在较低氧分压下制备的样品结构以岩盐矿为主导,而在较高氧分压下两相共存并以纤锌矿为主。这种相分离现象与裂解氧原子的密度有关。ZnMgO alloy allows for tunable optoelectronic devices.However,the compositional range between ZnO and MgO is interrupted by a crystalline miscibility gap where the wurtzite crystal structure of ZnO is structurally incompatible with the rocksalt structure of MgO.In this article,ten periods of ZnO / ZnMgO superlattice were produced by plasma-assistant molecular beam epitaxy on cplane sapphire substrate with different oxygen condition.It is found that the sample grown at lower oxygen flow and radio-frenquency( RF) plasma power tends to form rocksalt phase.With the increase of oxygen flow and RF plasma power,wurtzite phase tends to dominate and phase segregation is enhanced.The phase transform affected by the oxygen atoms density is reasoned by the formation enthalpies of ZnO and MgO.国家自然科学基金(61076084)资助项

Design and Fabrication of Stack Micro-Direct Methanol Fuel CellUsing Silicon and PDMS

在堆栈式微型直接甲醇燃料电池μ-dMfC(MICrO-dIrECT METHAnOl fuEl CEll)中,为了避免硅基流场板因为封装压力过大而破裂,采用了硅和PdMS(POlydIMETHylSIlOXAnE,聚二甲基硅氧烷)材料分别制作阳极和阴极流场板。首先,采用微机电系统MEMS(MICrO-ElECTrO-MECHAnICAl SySTEMS)技术制作硅基阳极流场板。其次,通过铜箔与阴极流场板一体成型、有机清洗和PdMS表面活化等改进措施显著提升了PdMS阴极流场板金属化的能力。最后,比较和分析阳极流场板上3种不同结构的流道形式的堆栈式μ-dMfC的输出性能。实验结果表明,活化后的PdMS阴极流场板与Cr/Au的粘附性能和粘接强度显著提高,同时阳极流场板的流道一半开设为凸台,一半开设为通孔时,其堆栈式μ-dMfC的输出性能最优。最大输出电流密度为81.25 MA/CM2,最大输出功率为7.73 MW/CM2。采用硅和PdMS材料分别制作流场板,不仅简化了堆栈式μ-dMfC的结构,而且能够缓冲锁紧力,有效保护硅基阳极流场板。同时优化阳极流场板上的流道结构,能够有效提升堆栈式μ-dMfC的输出性能。In order to avoid cracks of the silicon flow field plate caused by high package pressure,silicon and PDMS(Polydimethylsiloxane)are used as anodic and cathode flow field plate respectively in the stack μ-DMFC(Micro-direct methanol fuel cell).The anodic flow field plate based on silicon is fabricated with MEMS(Micro-Electro-Mechanical Systems)technology,and cathode flow field plate is fabricated using PDMS and its metallic performance is evidently improved by means of integral shaping of copper foil and cathode flow field plate,organic cleaning and activation on PDMS surface.The output of stack μ-DMFC is tested and analyzed,in which 3 different flow channel structures on the anodic plate are introduced.Tested results verify that adhesive capability and strengthen between post-activated PDMS and Cr/Au are greatly improved,and when micro blocks and through holes are introduced alternately in the flow channel of anodic flow field plate the stack μ-DMFC can obtain the maximum output,with voltage of 0.5 V,current density of 81.25 mA/cm2 and output power density of 7.73 mW/cm2.This study shows that using silicon and PDMS as flow field plate respectively not only simplifies the structure of stack μ-DMFC but also cushions clamping force and effectively protects anodic flow field plate,and furthermore to increase the output of stack μ-DMFC by optimizing structure of flow channels on the anodic flow field plate.国家自然科学基金重点项目(60936003

间充质细胞外泌体促进小鼠胰岛内皮细胞血管生成的研究

目的探讨间充质细胞（MSC）外泌体对低氧条件下胰岛内皮细胞（MS-1）血管生成的影响。方法 MSC无血清低氧条件培养48 h,超滤离心法富集条件培养基中的外泌体,采用电镜和Western Blot的方法进行鉴定;通过血管形成试验比较分析不同条件下:常氧培养组（NOR组,21%O2、5%CO2）、低浓度氧培养组（HYP组,2%O2、5%CO2）、外泌体+低浓度氧共培养组（HYP+EXO组,2%O2、5%CO2）,MS-1细胞的血管形成能力;image J软件分析血管形成长度;PCR、Q-PCR检测血管内皮生长因子（VEGF） RNA水平的表达,Western Blot检测VEGF、HIF1α蛋白水平表达以及mTOR信号通路激活情况。采用单因素方差分析和SNK-q检验统计学分析。结果超滤离心法富集的MSC条件培养基中的外泌体,大小为30～100 nm,表达CD9,CD63,CD81等外泌体表面标志物;血管形成试验结果显示,低氧促进MS-1血管生成,HYP+EXO组形成明显的血管网状结构;HYP+EXO组血管形成相对长度（2386.0±137.7）像素与NOR组（393.3±174.2）像素和HYP组（1467.0±230.0）像素相比增强,差异有统计学意义（t=12.30,P=0.0065;t=15.74,P=0.0040）; PCR结果显示,HYP+EXO组VEGF相对表达量（20.26±9.972）较常氧对照组（1.000）和低氧组（6.521±3.501）均增强,差异有统计学意义（t=5.462,P=0.0009;t=4.238,P=0.0038）;同时,Western Blot结果显示VEGF蛋白水平表达升高,HIF1-α表达上调,mTOR发生磷酸化。结论 MSC外泌体可促进低氧条件下的小鼠胰岛内皮细胞血管生成。MSC外泌体可能通过上调HIF1-α,调节VEGF表达,激活mTOR信号通路,促进胰岛内皮细胞血管生成。国家自然科学基金青年项目(81601618);;福建省自然科学基金面上项目(2016J01582、2016J01580、2018J01349);;福建省科技创新联合资金重大项目(2017Y9127

骨髓间充质细胞联合PDMS支架构建移植胰岛微环境的实验研究

目的为了提高移植胰岛的活性和功能,构建适合移植胰岛生存的微环境。方法采用聚二甲基硅氧烷(PDMS)和氯化钠晶体构建三维支架,联合骨髓间充质细胞(MSCs)、纤维蛋白和胰岛共同构建迷你\"人工胰腺\"。采用链脲佐菌素(STZ)诱导的糖尿病大鼠移植模型评价效果,将\"人工胰腺\"移植到糖尿病大鼠大网膜内,对照组行假手术,术后隔天监测移植大鼠血糖水平;数据采用t检验和曼-惠特尼U检验。结果用PDMS构建的三维巨孔支架,支架内可见大量不规则孔洞空间。胰岛和MSCs可成功装载入支架内,HE染色结果显示,支架孔内存在胰岛,胰岛周围包绕有MSCs。糖尿病大鼠大网膜内移植结果显示,移植后各时间点(1,3,5,7 d),\"人工胰腺\"移植组糖尿病大鼠血糖水平分别为(278.70±86.06) mg/dl、(323.50±44.29) mg/dl、(283.30±74.00) mg/dl、(304.80±13.33) mg/dl,较假手术对照组(606.00±52.40) mg/dl、(589.70±55.78) mg/dl、(615.00±54.84) mg/dl、(630.30±48.17) mg/dl均降低,差异具有统计学意义(t=7.96、9.15、8.82,U=0.00,P均<0.01)。结论 MSCs联合PDMS三维支架构建的微环境,可为移植胰岛提供生存的环境,为临床开展胰岛移植提供新的策略

Population genetic structure of Chinese black sleeper (Bostrychus sinensis) in China coast based on SSR and SNP marker

中华乌塘鳢是一种潮间带滩涂鱼类，其生活习性比较特殊如栖息于洞穴中，产卵于洞穴中，亲鱼具有护卵行为，仔鱼无浮游期，成鱼不洄游，活动空间十分有限等。这些因素导致其扩散能力较弱，对环境的变化十分敏感。因此开展中华乌塘鳢的种群遗传结构研究可以从生物学的角度了解我国海岸带地质变迁历史以及人类活动对潮间带生态系统的影响，也为中华乌塘鳢资源的保护和遗传育种提供了基础性资料。本文开发了SSR和SNP两种分子标记并应用这两种标记对中国沿海的12个群体以及1个越南群体共13个群体进行群体遗传分析。主要研究结果如下： 1SSR标记和SNP标记的开发 利用磁珠富集法从中华乌塘鳢富集文库中成功开发出20个SSR位点...Chinese black sleeper (Bostrychus sinensis), a kind of mudskipper, which is troglobic and habits in intertidal zone, has reproductive strategy of protecting eggs. There is no dispersal stages for larval and they do not migrate but stays in limited spaces, which causes Chinese black sleeper seldom spread. Therefore, the sensitivity to the environment can be a type of useful indicator. Therefore, th...学位：理学硕士院系专业：海洋与环境学院海洋学系_海洋生物学学号：2242009115115

生物发光成像无损伤研究植物生物钟的方法

植物生物钟系统是植物为了适应地球自转进化出的以约24小时为周期的分子系统,通过感知并整合外界周期性变化的环境信号进而协调细胞内相应基因的表达和能量状态,赋予植物对生存环境的适应性并参与调控多个植物生长发育过程。目前,越来越多的研究聚焦于解析植物生物钟的分子机制,基于此也衍生出很多研究生物钟表型的方法。该文在总结已有生物钟检测方法的基础上,重点介绍生物钟表型实验中最常用且比较稳定可靠的实验方法,以期为生物钟的表型研究尤其是生物钟机制研究提供技术支持与借鉴

Population genetic structure of Pneumatophorus japonicus in the Taiwan Strait

以往研究表明,台湾海峡的鲐鱼分属2个地理种群,即东海种群和闽南——粤东地方种群。为研究这2个种群的遗传结构,对鲐鱼闽东(30尾)和闽南(30尾)种群进行了AflP分析,8对选择性引物在2个种群60个个体中,共扩增出497个位点,其中多态位点343个。闽东和闽南种群的多态位点比例、nEI遗传多样性指数和SHAnnOn遗传多样性指数分别为57.75%、64.59%,0.1779、0.2123,0.2725和0.3228,2个种群的遗传多样性处于同一水平。与其他鱼类对比显示,台湾海峡鲐鱼种群的遗传多样性水平高。生境广及生命周期短被认为是台湾海峡鲐鱼具有较高遗传变异水平的原因;基因分化系数gST、SHAnnOn遗传多样性指数和AMOVA分析均显示鲐鱼的遗传变异主要来源于种群内,而种群间无明显的遗传分化。nM显示2个种群间基因交流频繁。种群的显性基因型频率分布显示2个种群有基本相同的种群遗传结构。结果表明,鲐鱼闽东和闽南种群间无明显的遗传差异。幼体较强的扩散能力、海洋环流及洄游特性可能是造成台湾海峡鲐鱼种群间遗传同质性较高的原因。The chub mackerel Pneumatophorus japonicus distributes in Indo-Pacific Oceans and occurs along coastal waters of China,including the East China,South China and Yellow Seas.With the fishery collapses of the three top commercial marine fishes(the large yellow croaker Pseudosciaena crocea,the little yellow croaker P.polyactis and the largehead hairtail Trichiurus lepturus),the fishery of P.japonicus has become important since the 1980s.Based on the migration pattern,morphological and biological characteristics,and tagging experiment,two populations of P.japonicus were initially identified in the Taiwan Strait,i.e.the East China Sea population in eastern Fujian and population in Southern Fujian-Estern Guangdong.Knowledge on population structure is essential for developing fisheries management and conservation measures.In this study,specimens of P.japonicus were sampled from eastern and southern Fujian waters in 2009—2010,with total lengths of 204.7—300.2 mm(n=30) and 214.1—311.5 mm(n=30),respectively.Amplified fragment length polymorphism(AFLP) was used to analyze the genetic diversity and variation of the East China Sea and Southern Fujian-Estern Guangdong populations in the Taiwan Strait and its adjacent waters.AFLP bands were scored for presence(1) or absence(0) and transformed into 0/1 binary character matrix.AMOVA was performed in Arlequin 3.1.Number of polymorphic loci,Nei genetic diversity,Shannon genetic diversity index,genetic similarity and genetic distance between populations,coefficient of gene differentiations(Gst),gene flow(Nm) and dominant gene frequency were conducted in POPGENE 1.31.A total of 497 loci ranging in size from 100 bp to 1000 bp were detected from 60 specimens of P.japonicus based on eight primer combinations,of which 343 were polymorphic;however,no population specific band was found.The number of bands per primer combination varied from 50 to 81 and the polymorphic bands per primer combination ranged from 60.00% to 94.29%.The proportion of polymorphic loci,the Nei genetic diversity and Shannon genetic diversity index had no significant difference(P>0.05) between the two populations with 57.75%,0.1779 and 0.2725 in eastern Fujian waters,and 64.59%,0.2123 and 0.3228 in southern Fujian waters,respectively.The Gst value,Shannon genetic diversity index and AMOVA analysis showed that the genetic variation mainly existed among individuals within population.Nm showed the frequent gene flow between the two populations.Dominant gene frequency revealed that both populations had a similar genetic structure.This study reveals that the genetic diversity of the two initially proposed populations is at the same level.We propose that the stocks of P.japonicus in the Taiwan Strait belong to the same population.Further studies using co-dominant markers are needed for a better understanding of the population genetics of P.japonicus.The genetic diversity of P.japonicus in the Taiwan Strait is considerably higher than some commercially important marine fishes in coastal waters of China,such as the Hong Kong grouper Epinephelus akaara,Yellow drum Nibea albiflora,Barfin flounder Verasper moseri and Silver pomfret Pampus argenteus.Wide distribution and short reproductive cycle may contribute to high genetic diversity of P.japonicus.Annual migrations and larval drift in the ocean currents can explain the genetic homogeneity in the studied areas.Currently,the fishery of P.japonicus in southern Fujian waters remains stable;however,it shows a decline in eastern Fujian waters.Therefore,timely and effective management can ensure the sustainable use of P.japonicus wild stocks in China.福建省科技计划项目(2007I0005

实用室内可见光通信连续干扰的消除

针对发光二极管之间的多径干扰,提出了采用QR分解的信道均衡算法消除干扰的方案。首先建立基于离散傅里叶变换扩频的正交频分复用技术的电力线与可见光融合通信系统,并考虑了由两个发光二极管之间的电线差所引发的多径干扰,然后比较了该系统下采用QR分解的信道均衡算法和传统信道均衡算法下的误码性能。结果表明,采用QR分解的信道均衡算法可消除由发光二极管之间的电线差引起的多径干扰,从而提高系统的传输性能

基于小波变换的OFDM在电力线通信系统中的应用

研究了基于DWT（小波变换）的OFDM（正交频分复用）和FFT（快速傅里叶变换）的OFDM两种不同调制方式在PLC（电力线通信）系统中的性能。首先建立了两种不同调制方式下PLC的系统模型,然后在AWGN（加性高斯白噪声）和子CFO（载波频率偏移）的干扰下,分析了两种系统的误码性能以及峰均功率比的分布。通过仿真发现,在PLC系统中,DWT-OFDM系统比FFT-OFDM系统更具优势,在未来的PLC系统中必将发挥重要的作用

Cultural and psychological changes during the social transformation in China: Sociological research and its enlightenments to psychologists

社会心理学有着社会学和心理学两种取向。虽然多数时候相对独立发展,但两者都对现代化带来的社会转型和变迁非常关注。社会学家从社会或社会结构的变化和人的变化两个方面对社会转型进行了大量研究,前者涉及城市(镇)化、社会阶层、社会流动性、家庭结构等,后者主要涉及中国体验、社会心态、群体心理、组织心理等。总体上,现有研究显示,现代社会个体主义上升,同时许多传统集体主义价值在式微。和心理学取向的研究相比,社会学取向的研究具有这些特点：倾向于采用本位概念、质性研究方法,特别关注中观群体心理,关注政治和政策影响,更具历史宏观视野等,这些都是心理学取向的社会心理学家需要学习和借鉴的地方。期待两种取向的社会心理学家在未来的研究中能有更多的合作,共同促进对转型过程中的中国和中国人的理解。</p