Research of chemical exchange saturation transfer in brain

化学交换饱和转移(chemical exchange saturation transfer,CEST)成像是在磁化传递及化学交换理论基础上发展起来的一种磁共振成像新方法,其扩展了磁共振分子影像新领域,但还处于研究阶段。其以细胞内物质为内源性对比剂,通过水信号间接检测代谢物信息,进行组织的酸碱度成像及其各种代谢物成像。本文主要探讨MRI领域中与水相关的化学交换饱和转移现象,阐述其原理、研究现状及其在不同场强磁共振仪上脑部疾病的应用。Chemical exchange saturation transfer(CEST) imaging is a new method for magnetic resonance imaging theory of exchange in the magnetization transfer and chemical, the expansion of the new field of molecular magnetic resonance imaging,but it's still in the research stage. The intracellular substances as an endogenous contrast agent, through the indirect detection of metabolite water signal information for tissue p H imaging and imaging of various metabolites. This paper mainly discusses the chemical and water exchange in the field of MRI saturation transfer phenomenon,expounds the principle, research status and the application in brain diseases used the different field strength clinical MRI scanner.2014年厦门市科技局科技惠民计划项目(编号:3502Z20144052)~

钛酸纳米管前驱体水热制备TiO_2:水热媒介对结晶度及光催化活性的影响

以钛酸纳米管为先驱体,180℃24 h同一水热条件下,利用H2O、HNO3、KBF4以及HNO3+KBF4的4种水热媒介溶液,制备了高结晶度高光催化活性的TiO2,并研究了水热媒介对TiO2结晶度、表面羟基和光催化活性的影响。通过扫描电镜(SEM)、X射线衍射(XRD)、红外测试(FTIR)、X射线光电子能谱(XPS)、紫外可见漫反射吸收光谱(UV-Vis)进行了结构表征。光催化活性通过降解甲基橙溶液进行了评价。结果表明,与其他3种媒介相比,HNO3+KBF4溶液为水热媒介制备的锐钛矿晶型TiO2,结晶度高,表面羟基含量高,因此,呈现高的光催化活性

Small angle X-ray scattering of the colloidal crystal

The monodisperse polystyrene spheres are assembled into the colloidal crystal on the glass substrate by vertical deposition method, which is aimed at the so-called photonic crystal applications. The structural information of the bulk colloidal crystal is crucial for understanding the crystal growth mechanism and developing the various applications of colloidal crystal. Small-angle X-ray scattering (SAXS) technique was used to obtain the bulk structure of the colloidal crystal at Beamline 1W2A of BSRF. It is found that the SAXS pattern is sensitive to the relative orientation between the colloidal sample and the incident X-ray direction. The crystal lattice was well distinguished and determined by the SAXS data

磷掺杂中空碳球的制备及其电容性能研究

以酚醛预聚体和苯乙烯为原料通过水热法一步合成中空聚合物球HPS，再以三氯化磷为反应剂通过傅-克反应对HPS处理得到含磷交联聚合物，经高温碳化和KOH活化制备了磷掺杂中空碳球AP-HCS。采用FT-IR、TG、SEM、TEM、Raman、BET、XPS等手段对含磷聚合物和碳材料的组成、结构与形貌进行表征，测试了碳材料在1mol/L H2SO4介质中的电容性能。结果表明，AP-HCS的比表面积可达2177m2/g，在1A/ g电流密度下，比电容为288F/g，5A/g电流密度下经循环充放电5000次后比电容值仍能保持88.9%，具备良好的电容性能。国家自然科学基金项目(51673161,51773172)福建省重大科技创新平台(2014H2006

TiO_2 Photocatalytic Deactivation and Regeneration vs Adsorbed NO_3~- Concentration

通讯联系人：E-mail:[email protected][中文文摘]以乙醛作为活性标的,通过人为控制表面附着NO3-浓度,检测TiO2对乙醛的吸附能力和光催化降解能力,得出了TiO2光催化失活复活特性和表面附着NO3-浓度的定量关系。结果表明,表面附着NO3-浓度达到4.24wt%时,光催化降解能力降低50%;表面附着NO3-浓度达到10.50wt%时,TiO2的吸附能力降低50%;通过溢流状态下水洗2h,可除去98%的表面附着NO3-,使TiO2光催化活性复活。[英文文摘]The quantitative relation between deactivation and the adsorbed NO3-concentration was studied by intentionally controlling the adsorbed NO3-concentration .The photolysis ability and adsorption ability of TiO2 was detected against acetaldehyde as a probe.The results show that when the adsorbed NO3-concentration reaches 4.24wt%,photolysis ability decreases 50%;when the adsorbed NO3-concentration is 10.50wt%,the TiO2 adsorption ability decreases 50%;after water overflow-cleaning 2 h,the NO3-is removed by 98% and the photocatalytic activity is regenerated.厦门大学人才引进项目(No.0044-X12101)资助项

纪念五四宪法颁布暨全国人民代表大会成立五十周年理论研讨会纪要

今年 9月是五四宪法颁布、全国人民代表大会成立五十周年。五四宪法是新中国的第一部宪法 ,为我国的社会主义民主法制奠定了基础 ,具有划时代的意义。坚持和完善人民代表大会制度 ,是新的历史条件下推进政治体制改革和社会主义政治文明建设的重要内容。基于“以学术表达纪念、以纪念促进学术”的目的 ,中国社会科学院法学研究所于 2 0 0 4年 9月 5日举办了“纪念五四宪法颁布暨全国人民代表大会成立五十周年理论研讨会”。来自全国各地的 70余位代表莅临会议 ,研讨了诸多热点和前沿问题

Application High Resolution Solid State NMR in the Studies of Heterogeneous Catalysis

随着固体高分辨核磁共振技术的日益发展.已广泛应用于研究吸附及催化问题。它不仅能给出固体推化剂的结构信息，而且能反映催化剂表面被吸附分子的动态行为，尤其是可以原位跟踪催化反应的动态过程、检测反应的中间物种，从而为催化反应机理的研究提供方便。本文简要综述固体高分辨核磁共振技术在多相催化研究领域中的应用及其相关的最新发展。With the development in technology of high resolution solid state NMR, it has been used to study the adsorption and catalytic process in heterogeneous catalysis.It provides not only the de tail structural inFormation of catalytic active centres, but also the dynamic action of adsorbed probe molecules in catalysis surFace.It also can be used to trace the process of catalysis rcaction and to detect the intermediate (products).So NMR is a convenient tool For studying the catalytic reaction mechanlsm and the structure - activity relationship.The application and recent develop ment of high resolution solid state NMR spectroscopic investigation in heterogeneous catalysis are brieFly reviewed in the present paper

大学生网络贷款的影响因素分析——以欠发达地区某高校调查为例

大学生网络贷款在给大学生学习和消费带来便利的同时,也产生了不小的负面影响。通过对欠发达地区某高校1282名大学生的网络贷款调查,发现欠发达地区的大学生网贷情况并不严重。其贷款的主要目的是用于购买电子类产品,同时贷款利率奇高、贷款时多数家长并不知情。在对影响大学生进行网络贷款的因素分析中,得到了高年级、来自农村、家庭年收入较高、通过网络途径获知网贷消息的大学生较各自的参照组更倾向于进行网络贷款。因此,建议有关方面应在贫困大学生生活补贴、消费观念教育、监管网贷平台和家长知情等方面入手解决相关问题

The structural stability and electronic properties of monolayer BC_2 N

【中文摘要】 采用基于密度泛函理论的第一性原理方法,对二维BC2N薄片的结构稳定性和电子性质进行了系统的研究.计算了BC2N化合物16种可能的二维单层结构.对它们的能带结构分析发现,对称性最高的构型与石墨烯一样是一种半金属,而其他二维结构则为有不同带隙的半导体,其中最稳定的构型是带隙值为1.63eV的直接带隙半导体.对最稳定构型的差分电荷密度分析和Bader分析发现:在最稳定的构型中,C—C键、C—N键、C—B键和B—N键主要以共价键的形式呈现,也具有比较明显的离子性.在应力作用下最稳定构型的单层BC2N的带隙宽度会发生变化,压缩时带隙变宽,而拉伸时带隙变窄,但仍然为直接带隙半导体. 【英文摘要】 The structural stability and the electronic properties of two-dimensional monolayer BC2N are studied by employing the first principles method based on the density functional theory.16 polymorphic structures of monolayer BC2N are calculated.Analysis of the 16 band structures suggests that the structure with the highest symmetry is of a semimetal which is the same as graphene.All the other structures are of semiconductors with different band gaps,of which the most stable structure is of semiconductor with a d...国家自然科学基金(批准号:11004165)资助的课