Fabrication of copper nanorods by low-temperature metal organic chemical vapor deposition

Copper nanorods have been synthe-sized in mesoporous SBA-15 by a low-temperature metal organic chemical vapor deposition (MOCVD) employing copper (II) acetylacetonate, Cu(acac)2, and hydrogen as a precursor and reactant gas, re- spectively. The hydrogen plays an important role in chemical reduction of oganometallic precursor which enhances mass transfer in the interior of the SBA-15 porous substrate. Such copper nanostructures are of great potentials in the semiconductor due to their unusual optical, magnetic and electronic properties. In addition, it has been found that chemically modi- fying the substrate surface by carbon deposition is crucial to such synthesis of copper nanostructures in the interior of the SBA-15, which is able to change the surface properties of SBA-15 from hydrophilic to hydrophobic to promote the adsorption of organic cupric precursor. It has also been found that the copper nanoparticles deposited on the external sur- face are almost eliminated and the copper nanorods are more distinct while the product was treated with ammonia. This approach could be achieved under a mild condition: a low temperature (400℃) and vac-uum (2 kPa) which is extremely milder than the con- ventional method. It actually sounds as a foundation which is the first time to synthesize a copper nanorod at a mild condition of a low reaction temperature and pressure.     

Cu表面氧化规律及其对铜—陶瓷材料键合强度的影响

在用于电力半导体模块的新型封装材料ＣｕＡｌ２Ｏ３陶瓷直接键合基板中,Ｃｕ与Ａｌ２Ｏ３间形成的键合,是通过ＣｕＡｌＯ化学键,以Ｃｕ２Ｏ为中介形成的,其键合强度主要受ＣｕＣｕ２Ｏ之间的结合力限制．从而可以认为,铜箔表面的氧化层对键合强度起着极为重要的作用．为此,文中对Ｃｕ表面的氧化规律、氧化层厚度与时间和温度间的关系及其对ＤＣＢ板界面键合强度的影响进行了仔细的研究,获得了较理想的结果．     

铜(Ⅱ)-1,10-菲咯啉—赤藓红水相荧光反应——荧光猝灭法测定痕量铜

研究了在TritonX-100存在的水溶液中铜(Ⅱ)-1,10-菲咯啉-赤藓红体系的荧光猝灭反应.铜与1,10-菲咯啉(Phen)和赤藓红(TIF)反应形成组成为[Cu(Phen)_2](TIF)的离子缔合络合物并引起赤藓红的荧光猝灭,此反应具有高的灵敏度,其检测限为3.6μg·L~(-1)铜.研究了反应的适宜条件和其它离子的影响.在用二苯硫腙-CCI_4分离和预富集后,方法可用于水和土壤样品中痕量铜的测定.     

铜代谢紊乱对脑神经系统疾病的影响

铜是维持哺乳动物正常生理活动的微量元素,体内铜的含量与细胞呼吸、自由基防御、血管生成、神经细胞和机体的生长发育有密切关系,它还参与脑生理活动的调节.体内铜的含量、转运及分布都受到精密的调控,铜元素缺乏和过量时都严重影响机体健康.铜及铜相关酶生物系统中对生命过程有着重要的作用,其代谢异常往往会导致严重的神经症状和神经系统疾病.本文将综述铜代谢紊乱对脑神经系统疾病的影响.     

新型介孔分子筛Cu/MCM-41的合成和表征及其催化氧化性能研究

 以十六烷基三甲基溴化铵为模板剂,正硅酸乙酯为硅源,硝酸铜为无机源,用水热法合成了新型介孔分子筛Cu/MCM-41.用N₂吸附/脱附,XRD,FI-IR和UV-Vis对合成材料进行了表征,结果表明合成的介孔Cu/MCM-41具有六方孔道,且Cu离子已高度分散于硅的分子骨架中,并呈四配位键合.讨论了Cu/MCM-41氧化苯酚制备对苯醌的催化活性.     

一种含铜固体电极在新型无膜生物电化学系统中的应用研究

采用壳聚糖修饰电极吸附溶液中Cu(Ⅱ)制得含铜固体电极,将其用做新型无膜生物电化学系统(MACMCB)阴极。研究固体电极Cu(Ⅱ)质量和外阻对MACMCB电压的影响。结果表明,系统电压与含铜固体电极Cu(Ⅱ)质量及系统外阻正相关,最大输出电压达0.6346 V。该系统Cu(Ⅱ)还原效率高于92.75%,表明Cu(Ⅱ)做电子受体得电子能力强,Cu(Ⅱ)几乎被全部还原。MACMCB与微生物燃料电池(MFC)的效率对比结果表明,在一定时间内,MACMCB在底物降解效率和产能输出方面明显优于MFC,推荐含铜固体电极更换时间为10~30小时。含铜固体电极中Cu(Ⅱ)主要以Cu SO4分子形式存在,放电后Cu(Ⅱ)的主要还原产物为单质Cu,含少量Cu2O,另外掺杂部分Cu元素的磷化物和氯化物沉淀。     

模拟城市酸雨条件下形成铜锈的稳定性研究

设计了可以重复获得铜锈的试验方法,把形成的铜锈从基体上剥离,填充到多孔微电极中,在模拟城市强酸雨条件下(0.2 gL-1Na2SO4+0.2 gL-1Na HCO3,pH值为3的酸性溶液中),测试了铜锈的电化学行为.在硼酸溶液中,通过循环伏安法测试表明,铜锈的电化学反应存在Cu(II)/Cu(I)和Cu(I)/Cu两个还原过程;对比试验发现,在腐蚀型测试介质中(模拟城市酸雨),阳极区可以观察到氧化现象,但是由于BiTA对铜锈的稳定作用,峰值电流明显降低.明确了BiTA对铜锈溶解的抑制效果.     

亚相金属离子对两亲8—氨基喹啉配体成膜性能的影响

目的：为研制有机纳米的光电器件。方法：设计合成了一种新含长链烷基的8-氨基喹啉衍生物,2-十二烷基丙二酸二（8-氨基喹啉）酰胺（H2A）两亲配体,研究了亚相不同金属离子对其成膜性能的影响,特别是不同浓度的亚相Cu^2 和不同铜盐对H2A成膜性能的影响。结果：Cu^2 离子对H2A具有特殊的配位作用。结论：新型配体与铜离子的特殊配体作用,可使其单分子膜或多层膜在化学传感器方面存在潜地的应用前景。     

硫酸铜结晶母液制备砷酸铜的工艺技术

采用二段中和法研究了硫酸铜结晶母液制备砷酸铜的工艺过程,用XRD图探讨了砷酸铜的分子结构式．结果表明只要控制一定的pH值、反应时间、温度和铜砷质量比,便可以产出合格的砷酸铜,砷酸铜的结构式为Cu5AS4O15·9H2O．利用含砷物料制备砷酸铜对于环境保护具有重要意义．     

结晶器铜板上激光熔覆镍基合金

利用5kWCO2激光器在结晶器铜板上熔覆镍基合金,并研究了熔覆层组织性能.选用与结晶器铜板成分相近的镍基自熔合金粉末Nickel-baseHMSP1015-00(Ni1015),利用等离子喷涂技术在铜板上预涂Ni1015合金,然后再采用高能量密度激光进行重熔.借助OM,SEM和显微硬度计分析测定了涂层的显微组织形貌、组织成分和截面显微硬度分布情况.所得到的熔覆层表面平整均匀,与基体为冶金结合;熔覆层平均显微硬度为270HV0.05,是基体的3.2倍(85HV0.05).确定出本实验合适的激光熔覆工艺参数功率密度为1.58×102kW/cm2时,扫描速度为3~4m/min.     

3%NaCl溶液中碳-铜短路体系接触腐蚀机理

应用旋转圆盘电极(RDE)法、浸渍腐蚀试验法及腐蚀表面的X射线衍射分析法研究了3%NaCl溶液中碳-铜短路接触腐蚀的机理.结果表明,该腐蚀属O_2去极化腐蚀,其阴极去极化反应一般为扩散控制.在与腐蚀电流相对应的电位区内,在碳电极上O_2的阴极还原电流密度约为铜电极上的还原电流密度的二倍,并且,由于碳膜的存在,在铜表面上形成了铜氧化物-铜电偶,因而促进了铜的腐蚀.     

焦磷酸盐镀铜工艺研究

通过铜镀层做基体材料的中间层或底层,可以获得许多具有特殊性能的镀层。氰化镀铜是应用最为广泛的底层镀铜工艺,但是氰化镀液中含有剧毒物.焦磷酸盐镀铜是替代氰化镀铜的最重要电镀工艺,但它的最大缺点在于附着力不好.文章用电化学方法研究了工艺条件对焦磷酸盐镀铜的镀层性能(特别是结合力)影响.结果表明:镀液的温度、搅拌速度、电流密度直接影响镀层性能;最佳工艺条件为:温度45℃,时间60 min,搅拌速度200 r/min,阴极电流密度1.5A/dm2。本研究结果为焦磷酸盐镀铜提供了实用的参考价值.     

催化动力学光度法测定微量铜——Cu(Ⅱ)-甲基橙-H_2O_2体系

研究了在弱酸性介质中微量铜催化 H2 O2 氧化甲基橙褪色的指示反应 ,探索了催化动力学测定铜 ( )的新方法 .该方法测定的线性范围 0 .0 5～ 3.5 μg/ 2 5 m L,本法已用于人发样及水样中的痕量铜的测定 .     

检验茶叶中重金属元素铜含量的两种实验方法对比

金属铜是茶叶检测的重金属元素之一,根据国标GB5009.57《茶叶卫生标准的分析方法》,分别采用铜试剂法和原子吸收分光光度法对山东省青岛崂山同一地块不同季节的茶叶进行了铜检测方法的对比研究,结果发现原子吸收分光光度法比铜试剂法操作过程简便、快速、准确、灵敏度高,回收率好,可以快速、准确的测定茶叶中金属铜的含量,是一种更好的适合于实验室内茶叶样品检验的测定方法。     

铜(I)配合物[(PPh3)2Cu(S2COMe)]的合成与结构分析

室温下,通过[(PPh3)2Cu(NO3)]与二硫化碳在甲醇和二氯甲烷混合溶剂中反应合成了铜(I)配合物[(PPh3)2Cu(S2COMe)],研究了配合物的物理化学性质和光谱性质,并经X-射线结构分析确定了配合物的分子结构,中心铜离子分别与来自三苯基膦的两个P原子和S2COMe-阴离子中的2个硫原子形成四面体结构.配合物属正交晶系,空间群P212121,晶胞参数如下:a=0.951 3(2)nm,b=1.807 5(4)nm,c=1.996 8(3)nm;V=343.34(12)nm3,Z=4,F(000)=1 440,Dcalcd=1.345 g.cm3,μ=0.880 mm-1,R=0.048 7,Rw=0.093 5.     

两种Cu(II)配合物的合成和结构表征(英文)

选取1,9—二(2—氟代苯基)—2,5,8—三氮杂壬烷与铜(Ⅱ)的苯甲酸盐和硝酸盐,合成了两个新的配合物[Cu(C18H23F2N3)(C7H5O2)(H2O)](C7H5O2)·2(H2O)(1)和[Cu(C18H23F2N3)(NO3)2]·(H2O)1/2(2),并获得其单晶,测定了晶体结构.单晶衍射数据显示化合物(1)属三斜晶系Pi空间群,化合物(2)属单斜晶系Cc空间群     

Novel thioether bond revealed by a 1.7 A crystal structure of galactose oxidase

Galactose oxidase is an extracellular enzyme secreted by the fungus Dactylium dendroides. It is monomeric, with a relative molecular mass of 68,000, catalyses the stereospecific oxidation of a broad range of primary alcohol substrates and possesses a unique mononuclear copper site essential for catalysing a two-electron transfer reaction during the oxidation of primary alcohols to corresponding aldehydes. Recent evidence arguing against a Cu(III)-Cu(I) couple implies the existence of a second redox-active site proposed to involve pyrroloquinoline quinone or a tyrosine radical. We now report the crystal structure of galactose oxidase at 1.7 A resolution. This reveals a unique structural feature at the copper site with a novel thioether bond linking Cys 228 and Tyr 272 in a stacking interaction with Trp 290. We propose that these molecular components stabilize the protein free-radical species essential for catalysis and thus provide a 'built-in' secondary cofactor. This feature may represent a new mechanism for mediating electron transfer in metalloenzymes in the absence of exogenous cofactors.     

反渗透与纳滤膜分离技术在铜矿废水回收中的应用研究

研究了反渗透和纳滤膜在铜矿废水处理回用情况,考察并对比了反渗透和纳滤膜的透过液浓度、膜通量、清洗状况以及对废水的浓缩倍数(浓缩液Cu2+浓度)等参数.试验发现,一级反渗透和纳滤的透过液浓度分别为8mg/L和14mg/L,对Cu2+的截留率分别达到96.64%和94.19%,二级纳滤浓缩液Cu2+浓度可达到4000mg/L以上,满足Cu2+回收的要求,二级反渗透膜脱盐处理后的产水Cu2+浓度可低至0.2mg/L以下,满足回用水要求.研究表明,将反渗透和纳滤膜分离技术应用到铜矿废水处理工程中是可行的,具有显著的经济利益和社会效益.     

Resonance as a measure of pairing correlations in the high-Tc superconductor YBa2Cu3O6.6

One of the most striking properties of the high-transition-temperature (high-Tc) superconductors is that they are all derived from insulating antiferromagnetic parent compounds. The intimate relationship between magnetism and superconductivity in these copper oxide materials has intrigued researchers from the outset, because it does not exist in conventional superconductors. Evidence for this link comes from neutron-scattering experiments that show the unambiguous presence of short-range antiferromagnetic correlations (excitations) in the high-Tc superconductors. Even so, the role of such excitations in the pairing mechanism for superconductivity is still a subject of controversy. For YBa2Cu3O(6+x), where x controls the hole-doping level, the most prominent feature in the magnetic excitation spectrum is a sharp resonance (refs 6-11). Here we show that for underdoped YBa2Cu3O6.6, where x and Tc are below their optimal values, modest magnetic fields suppress the resonance significantly, much more so for fields approximately perpendicular to the CuO2 planes than for parallel fields. Our results indicate that the resonance measures pairing and phase coherence, suggesting that magnetism plays an important role in high-Tc superconductivity. The persistence of a field effect above Tc favours mechanisms in which the superconducting electron pairs are pre-formed in the normal state of underdoped copper oxide superconductors, awaiting transition to the superconducting state.     

含砷低品位硫化铜矿生物堆浸工业试验

福建紫金山含砷低品位硫化铜矿年产300tCu和1000tCu生物堆浸工业试验结果表明:铜浸出率随着矿石粒度的减小而提高,矿石粒度为-30mm,浸出周期为270d,铜的浸出率达到80.58%;铜萃取率和电积电流效率随着浸出液pH值的降低和电积液中铁的质量浓度的增加而降低,当浸出液pH值下降到1.19时,铜萃取率下降到了50%;通过增加堆高、定期中和萃余液、增加负载有机相洗涤和活性炭+沙滤+气浮塔脱除电积原液中有机物等工艺改进后,降低了萃取剂、煤油和电能的消耗量,提高了铜的浸出速率,浸出周期为200d,铜浸出率为81.31%,铜萃取--电积的耗电量为2679.98kW.h.t-1,高纯阴极铜生产成本1.05万元.t-1.