水热法制备WO3纳米棒阵列及其光催化性能

采用水热法,以Na₂WO₄·2H₂O为原料,NaCl为添加剂,直接在氧化铟锡透明导电基底上制备了有序WO₃纳米棒阵列.利用X射线衍射、扫描电子显微镜、透射电子显微镜和高分辨透射电子显微镜等手段对制备的纳米棒进行了表征,考察了pH值对产物形貌、尺寸和取向性的影响.结果表明:单根WO₃纳米棒具有六方单晶结构,随着前驱液pH值的增大,平行于基底生长的WO₃纳米棒捆逐渐转变为垂直于基底生长的纳米棒阵列.另外,对制备得到的两种不同取向的WO₃纳米棒结构进行了光催化降解甲基蓝溶液的研究,发现相比于WO₃纳米棒捆结构,纳米棒阵列的光催化性能更高.      

复合溶剂热法合成Bi2S3纳米棒的研究

以铜试剂(二乙基二硫代氨基甲酸钠)为硫源、硝酸铋为铋源、丙三醇-水体系为溶剂,采用复合溶剂热法大规模合成了Bi2S3纳米棒.对所制备的样品用X射线粉末衍射(XRD)、透射电子显微镜(TEM)、场发射扫描电子显微镜(FESEM)等测试手段进行了表征.结果表明,所制备样品为纯相正交晶型,其形貌为分散性良好的单晶纳米棒,径向和轴向尺寸分别为30～50 nm和几微米.对Bi2S3纳米棒的形成机理进行了探讨,认为丙三醇-水复合溶剂及表面活性剂PVP对其形貌和尺寸均有重要影响. 复合溶剂热法;Bi2S3;纳米棒;丙三醇-水;PVP     

MoO_3纳米材料化学合成流程的研究

研究了制备纳米MoO3的各种流程;其中包括,沉淀法、水热法、CVD法、溶胶-凝胶法、共胶凝法、溶胶-水热法等。本文权衡与评估了它们的优点和缺点;突出了溶胶-水热法,应用于制备纳米MoO3纳米棒、纳米带、纳米纤维、纳米管等,不但具有分散性良好,而且分布均匀,克服了溶胶-凝胶法热处理界面开裂的困难,解决了水热合成耗时冗长等缺点。其中,一维单晶的尺寸与形貌,不仅取决于水热条件,而且,取决于溶胶的制备条件。研究结果还证明,溶胶-凝胶法特别适合于制备热力学亚稳态的六方相MoO3薄膜。     

专利名称:六方相MoO2纳米球堆积微米空心球及制备方法和应用

专利申请号:CN201110176820.2公开号:CN102328958A申请日:2011.06.28公开日:2012.01.25申请人:福州大学本发明涉及一种六方相MoO2纳米球堆积微米空心球及制备方法和应用,所述微米空心球的制备方法是将MoO3粉末与二乙烯三胺通过水热合成方     

锗纳米针状结构的制备与表征

以锗、二氧化锗为原料,铜片为沉积衬底,通过水热沉积过程制备出了锗纳米针状结构.采用扫描电子显微镜(SEM)、能量色散光谱(EDS)、透射电子显微镜(TEM)及高分辨透射电子显微镜(HRTEM)等检测手段对样品进行了分析与表征.结果表明,样品具有典型的针状特征,其长度大于10 μm,由单晶锗和无定形锗氧化物外层所组成.运用金属催化气-液-固和氧化物辅助生长机理,解释了锗纳米针状结构的形成与生长.     

溶剂热法合成CoS纳米晶及其表征

以六水合硝酸钴(Co(NO3)2·6H2O)和硫脲为原料,采用混合溶剂热法制备硫化钴(COS)纳米晶.利用X射线衍射(XRD),扫描电镜(SEM)和透射电镜(TEM)对硫化钴纳米晶的组成、粒径及表面形貌进行表征.结果表明,在180℃恒温条件下所得粉末样品为六方相CoS纳米粉末,粉末粒径在40nim左右.粉末的产率随温度...     

微波法合成硫化铋纳米棒

以柠檬酸铋、硫脲为反应原料,在表面活性剂存在下,采用微波法合成了直径为30～50nm的硫化铋纳米棒.利用X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等对其进行了表征.考察了表面活性剂种类、用量对硫化铋纳米棒形貌和晶型的影响.结果表明:β-环糊精(β-CD)和十六烷基三甲基溴化铵(CTAB)有利于形成硫化铋纳米棒,并且较低浓度的β-CD(约0.005mo.lL-1)有利于形成分散性较好的硫化铋纳米棒.初步探讨了制备方法对硫化铋纳米棒晶型和合成时间的影响.结果发现,微波法制备纳米硫化铋与回流法相比,其晶格的生长方向不同,并且可以节省约80%的反应时间.     

自牺牲模板法合成MnOOH纳米管的研究

以β-MnO2纳米管为自牺牲模板,在200 ℃不锈钢反应釜中保温48 h,首次合成了单斜相MnOOH纳米管.采用X射线衍射、透射电子显微镜、选区电子衍射、场发射扫描电子显微镜、高分辨率透射电子显微镜、X射线能谱仪等检测手段对所制备样品进行表征.结果表明,所制备样品为纯相的单晶MnOOH纳米管,直径为200～500 nm,长度可达几个微米. MnOOH;纳米管;单斜相;β-MnO2;自牺牲模板     

表面纳米晶化处理中碳钢的组织与力学性能

采用高能表面处理技术在40Cr钢的表面制备出具有纳米晶体特征的表面层.用扫描电子显微镜和透射电子显微镜研究了表面纳米层的微观结构,并利用纳米压入法测定了表面纳米层的硬度.结果表明,经过高能表面处理后,样品表面层的晶粒细化为纳米晶,平均晶粒尺寸约为11 nm,表面纳米层的硬度明显提高.     

MoO_2亚微米球的可控水热合成和表征

通过水热法合成了平均粒径约300~500nm的MoO2亚微米球。辅助剂PEG400在合成过程中,既作还原剂又作保护剂。探究了产物从MoO3纳米棒向MoO2亚微米球转变的最佳制备条件。采用XRD和SEM手段对产物进行了系统的表征。初步探讨了MoO3纳米棒向MoO2亚微米球转变的机理。     

A new remote subsite in ribonuclease A

The interaction between bovine pancreatic ribonuclease A (RNase A) and its RNA substrate extends beyond the scissile bond. Enzymic subsites interact with the bases and the phosphoryl groups of a bound substrate. We evaluated the four cationic residues closest to known subsites for their abilities to interact with a bound nucleic acid. Lys-37, Arg-39, Arg-85, and Lys-104 were replaced individually by an alanine residue, and the resulting enzymes were assayed as catalysts of poly(cytidylic acid) (poly(C)) cleavage. The values of Km and kcat/Km for poly(C) cleavage were affected only by replacing Arg-85. Moreover, the contribution of Arg-85 to the binding of the ground state and the transition state was uniform---Km increased by 15-fold and kcat/Km decreased by 10-fold. The contribution of Arg-85 to binding was also apparent in the values of Kd for complexes with oligonucleotides of different length. This contribution was dependent on salt concentration, as expected from a coulombic interaction between a cationic side chain and an anionic phosphoryl group. Together, these data indicate that Arg-85 interacts with a particular phosphoryl group of a bound nucleic acid. We propose that Arg-85 comprises a new distal subsite in RNase A---the P(-1) subsite.     

A patient with acquired haemophilia A and pemphigus

Haemophilia A is usually a genetic deficiency of coagulation factor VIII (F VIII). The development of antibodies against F VIII is a well known and frequent complication in the treatment of haemophilia A. Rarely, a F VIII inhibitor arises spontaneously, causing a condition which is known as acquired haemophilia A. We describe a patient with acquired haemophilia A and pemphigus, who presented with spontaneous haematomas of the extremities. Laboratory tests showed an activated partial thromboplastin time (aPTT) of 71 s (normal: 26-36 s), a F VIII concentration of 9% (normal: 60-140%), and a F VIII inhibitor-activity of 7.5 Bethesda Units/ml (B.U./ml, normal: 0). The haematomas disappeared within a few days and the laboratory tests normalized within 6 weeks, after administration of a booster of oral corticosteroids. One and a half years after the corticosteroids were stopped, both the clinical and the laboratory course of the patient has been uneventful. As far as we know, the combination of acquired haemophilia A and pemphigus has been reported in the literature only three times before. The diagnosis acquired haemophilia A should be considered in a patient presenting with a newly arisen haemorrhagic diathesis.     

A Question of Values: A Reply.

Replies to the comments of Karson, Baler, and Carroll (see record 2005-12006-001) suggesting that the planning of the program of research reported in America's Psychologists (see record 2004-15427-000) intentionally or unintentionally was influenced by value judgments. What they mean to say is that they believe the wrong values were assigned, especially in the study of factors influencing an individual psychologist's research contributions to psychology. The emphasis given to research publication, to which Karson, Baler, and Carroll object, occurred in our study of the way in which significant contributors differed from their less productive colleagues. Attention to publication was essential, we felt, since any contribution to science necessarily involves comunication with one's fellows about results. America's Psychologists did give consideration to other professional endeavors. I think we need to recognize that all of American psychology is today perplexed about the relative values to assign to research and to service in our growing field. Karson, Baler, and Carroll protest that decisions are being made about the desired characteristics of a clinical psychologist on traditional bases without enough attention being given to changing conditions and new roles played by clinical psychologists. For this position I think they can find full and unqualified support in America's Psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A bladder nephrogenic adenoma. A case report

OBJECTIVE: To report an additional case of nephrogenic adenoma of the bladder. METHODS/RESULTS: A case of nephrogenic adenoma of the urinary bladder in a 28-year-old female is described. Patient clinical history and diagnostic imaging findings are presented. CONCLUSIONS: Nephrogenic adenoma of the bladder is a rare benign tumor with specific histological features that has been associated with previous surgery, trauma, infections and lithiasis. Although it is currently not considered to be a premalignant lesion, its rate of recurrence is high (37%-49%). The treatment of choice is by transurethral resection and yearly cytological, ultrasound and cystoscopic follow-up evaluation to detect recurrence.