Mass Production of Bi3NbO7/Bi2Zn(2/3)Nb(4/3)O7 Composites and Their Visible-light Photocatalytic Activity

Series Bi3NbO7/Bi2Zn（2/3）Nb（4/3）O7 （BN/BZN） composites were synthesized through a facile solid state reaction method. The products were characterized by X-ray diffraction（XRD）, field emission scanning electron microscopy（FE-SEM） and UV-vis diffuse reflectance spectroscopy（DRS）. When BN： BZN=0.1 mole ratio, the BN/BZN composite showed the best visible-light-driven photocatalytic performance, which decomposed nearly 100% of Rh B（10 ppm, p H=3-4） within 40 min. The results demonstrated that in-situ solid state synthesis of BN/BZN composites could be an efficient strategy to develop new photocatalyst for environmental remediation.

MoO_(2)/ZnS复合材料改性隔膜实现锂硫电池稳定的高倍率性能

锂硫电池由于其高能量密度、低成本效益被认为是最有前途的下一代电池体系之一.然而多硫化物的穿梭效应大幅降低了锂硫电池的循环稳定性和寿命,严重阻碍其实际应用.无机金属化合物材料改性的隔膜不仅能抑制多硫化锂(LiPS)的穿梭效应,其部分特殊的晶面还能加速多硫化物的氧化还原反应动力学.本文在罗盘状ZnS表面原位生长球状的MoO_(2),制备MoO_(2)/ZnS复合材料.MoO_(2)对多硫化物有着较强的吸附作用,ZnS有着良好的电导率,两者的复合可加速电子传导效率和氧化还原速率.以所制备的MoO_(2)/ZnS作为隔膜改性材料,锂硫电池在5 C的大电流密度下,经过1000次循环后仍可以保持690 mAh g^(-1)的放电比容量,平均每圈的容量衰减率仅为0.014%,表现出优异的循环性能和倍率性能.

工艺参数对Zn-TiO_(2)复合镀层性能的影响

采用电沉积法在氯化物体系获得了Zn-TiO_(2)复合镀层,研究了颗粒添加量、电流密度和机械搅拌速度对镀层厚度和耐蚀性的影响,对工艺优化后的镀层进行了形貌和元素分布表征。结果表明:在TiO_(2)添加量为10 g/L、电流密度2 A/dm^(2)、搅拌速度为150 r/min的沉积条件下,获得的镀层厚度可达8.3μm,腐蚀电流最小为2.983×10^(-4) A;TiO_(2)颗粒成功共沉积到镀层当中,其质量分数为4.6%;镀层中Zn呈层状堆积分布,TiO_(2)颗粒分布在Zn层交界处。

Preparation and Application of Active Composite Antibacterial Material Containing Ag^+ and Zn^(2+)

A kind of active composite antibacterial material was prepared with CaHPO4 as the container, Ag^＋ and Zn^2＋ were adsorbed through ion-exchange, then it was doped with small scale of rare earth and photocatalyst, and was finally calcined at a certain temperature. The properties and application of the composite material antibacterial were investigated. Some tests show that the as-prepared antibacterial powders modified by opaque agents such os SnO2 and ZrO2, possess beautiful white and excellent climate resistance at normal temperatures and are promising candidate materials for antibacterial plastics and dope. The result of the application in glaze indicates that Ag^＋ can still exist stably, with no color change for the glaze, even being sintered at 1200℃ . SEM , EDS , antibacterial activity analyses and contrast tests reveal that the as-prepared antibacterial powders and the antibacterial glaze both have excellent antibacterial activities, without color change, in the case of dark or brightness.

Fabrication and Magnetic Properties of Composite Ni_(0.5)Zn_(0.5)Fe_2O_4/Pb(Zr_(0.52)Ti_(0.48))O_3 Nanofibers by Electrospinning

One-dimensional and quasi-one-dimensional nanostructure materials are promising building blocks for electromagnetic devices and nanosystems.In this work,the composite Ni0.5Zn0.5Fe2O4（NZFO）/ Pb（Zr0.52Ti0.48）O3（PZT） nanofibers with average diameters about 65 nm are prepared by electrospinning from poly（vinyl pyrrolidone） （PVP） and metal salts.The precursor composite NZFO/PZT/PVP nanofibers and the subsequent calcined NZFO/PZT nanofibers are investigated by Fourier transform infrared spectroscopy （FT- IR） ,X-ray diffraction （XRD）,scanning electron microscopy （SEM）.The magnetic properties for nanofibers are measured by vibrating sample magnetometer（VSM）.The NZFO/PZT nanofibers obtained at calcination temperature of 900 °C for 2 h consist of the ferromagnetic spinel NZFO and ferroelectric perovskite PZT phases,which are constructed from about 37 nm NZFO and 17 nm PZT grains.The saturation magnetization of these NZFO/PZT nanofibers increases with increasing calcination temperature and contents of NZFO in the composite.

Cracking Behaviour of Al_2O_3 Short Fibre/Al-5.5Zn Composite in TEM

The micromechanical behaviour of Al2O3 short fibre reinforced Al-5.5Zn matrix composite has been in-situ studied by using TEM. The results show that in the composite the nucleation and propagation of cracks take place mainly in the matrix, as well as in the region near the fibre/matrix interface. It has been also observed that the microcracks can close during unloading.So the fracture property can be characterized by crack open displacement (COD). The cracking characteristic may result from the large strength difference between the matrix and fibre.

Zn铁氧体—SiO_2复合材料溶胶—凝胶制备工艺优化研究

以硝酸铁、硝酸锌和正硅酸乙酯为起始原料 ,用溶胶—凝胶法制备了晶粒粒径在 1 5～ 4 2 .5nm的Zn铁氧体—SiO2 复合材料 ,并对溶胶—凝胶工艺及胶体形成机理进行了初步探讨。XRD分析结果表明 :5 0 0℃热处理已合成约 5 1 %尖晶石主晶相 ,并含有少量的Fe2 O3另相 ;90 0℃热处理则基本上消除了另相。

膨润土-钢渣复合颗粒对Zn^(2+)的去除机理

为了探索酸性矿山废水中重金属离子的高效协同处理方法和开发新型多功能处理材料,采用自行研制的膨润土-钢渣复合颗粒对含Zn^(2+)酸性矿山废水的去除效果和实验现象进行对比实验研究,并利用SEM和XRD进行微观分析,结果表明:该复合颗粒不仅可以释放碱度中和酸,而且对Zn^(2+)的吸附、化学沉淀作用发生于整个反应过程,对Zn^(2+)的平衡去除量可达8.01 mg/g;SEM表面微观分析揭示了复合颗粒表面吸附Zn^(2+)并形成沉淀后还会继续吸附Zn^(2+)并发生聚沉作用,即发生了吸附-聚沉协同作用;XRD微观分析进一步揭示了Zn^(2+)在复合颗粒表面的赋存状态主要以Zn-SiO相结合的矿物相以及Zn_(12)(CO_3)_3SO_4(OH)_(16)聚合沉淀存在。膨润土-钢渣复合颗粒可发挥吸附-聚沉协同作用,是处理含重金属离子酸性矿山废水的优良多功能矿物环保材料。

(Zn-Co)-TiO_2复合电镀的工艺研究

研究了微酸性氯化物体系中 ( Zn- Co) - Ti O2 复合电镀的工艺 ,探讨了镀液组成及工艺条件对复合镀层中 Co及 Ti O2 含量的影响 ,得到了 ( Zn- Co) - Ti O2 复合电镀的最佳工艺。并对 ( Zn- Co) -Ti O2 复合镀层的耐蚀性进行了考察 ,与 Zn-

Zn^(2+)对球等鞭金藻生长及生化成分的影响

探讨了不同浓度Zn2+对球等鞭金藻细胞生长及细胞内多糖、叶绿素、蛋白质等生化成分含量的影响。研究表明,浓度低于4.0mg/L的Zn2+对球等鞭金藻的生长无明显抑制作用。当Zn2+浓度高于10.0mg/L时,则对球等鞭金藻的生长产生明显的抑制作用,随着Zn2+浓度的升高,球等鞭金藻胞内叶绿素和多糖含量降低,而蛋白质含量则明显升高。

纳米ZnO·Bi_2O_3·La_2O_3复合粉体的Sol-Gel法制备工艺与表征

纳米ZnO作为应用前景意义很大的半导体材料,有较高的研究价值,为此以Zn(AC)2.2H2O、La2O3、Bi(NO3)3.5H2O为主要原料,柠檬酸为络合剂,利用溶胶-凝胶法制备了纳米ZnO.Bi2O3.La2O3复合粉体.通过实验研究制备纳米ZnO.Bi2O3.La2O3复合粉体的最佳工艺条件,并利用x-射线衍射(XRD)、透射电镜(TEM)、比表面积测定对制备的复合粉体性能进行表征.结果表明,在最佳工艺条件下,干凝胶在600℃条件下煅烧2 h,得到了粒径分布约为54 nm、比表面积为120.77 m2/g的纳米ZnO.Bi2O3.La2O3复合粉体,说明溶胶-凝胶法制备纳米ZnO有较好的结果.

Zn^(2+)-Ni^(2+)-Al^(3+)-MnO_4^--LDHs制备及其表征

锌、镍和铝物质的量比为1∶3∶2,以尿素为沉淀剂,采用均相沉淀技术制备Zn^(2+)-Ni^(2+)-Al^(3+)-CO_3^(2-)-LDHs。以Zn^(2+)-Ni^(2+)-Al^(3+)-CO_3^(2-)-LDHs为前驱体,分别与Cl-和MnO_4^-进行离子交换,将MnO_4^-引入Zn^(2+)-Ni^(2+)-Al^(3+)-LDHs层间制备Zn^(2+)-Ni^(2+)-Al^(3+)-MnO_4^--LDHs新型复合材料。通过XRD、SEM、FT-IR和EDS等对合成产物Zn^(2+)-Ni^(2+)-Al^(3+)-MnO_4^--LDHs进行表征。结果表明,Zn^(2+)-Ni^(2+)-Al^(3+)-MnO_4^--LDHs复合材料结晶度较高,层间距为0.912 nm,具有明显的六边形层状结构,片层横向尺寸约为3μm,厚度约为100 nm。

PVP/Zn(CH_3COO)_2复合纤维电纺丝条件的研究

采用静电纺丝法在18～32kV、PVP／Zn（CH3COO）2前驱体浓度为15％、20％、24％和28％，纺丝距离为6～15cm的条件下，制备了直径为200～500nm的微纳米纤维。通过扫描电子显微镜（SEM）分析得出在纺丝电压为25～28kV，纺丝距离为10～12cm，溶液质量浓度为24％时纺出的微纳米纤维结构较为均一。

Zn-SiO_2复合涂层在水介质中的耐冲刷腐蚀性能

渗锌钢不耐冲刷腐蚀 ,其应用受到了限制。在料浆渗锌涂层上采用溶胶 -凝胶法研究了制备SiO2 涂层的过程 ,获得了具有优异抗蚀性能的Zn -SiO2 复合涂层的新技术。EDS和XRD分析证明 ,Zn -SiO2 复合涂层的外层是一层较薄的非晶态SiO2 薄膜 ,内层是与基体结合紧密的由FeZn11,FeZn9,FeZn7相组成的Zn -Fe合金层。在 4 0℃自来水中冲刷腐蚀 10 0h后 ,Zn -SiO2 复合涂层的腐蚀速率约是渗锌层的 1/ 2 0 ,2 0钢的 1/ 170。在 4 0℃ ,3.5 %NaCl溶液中冲刷腐蚀 10 0h后 ,Zn -SiO2 复合涂层仍然保持光泽的表面。电化学测试结果表明 ,渗锌涂层涂覆一层SiO2 薄膜后电极电位大幅度向正方向移动 ,是Zn -SiO2 复合涂层提高抗腐蚀性能的主要原因。

超声波辅助铁基体电沉积Zn-Ni-P/纳米ZrO_(2)复合镀层及性能研究

通过电沉积并辅助超声波振荡在铁基体上制备出Zn-Ni-P/纳米ZrO_(2)复合镀层。研究了镀液中ZrO_(2)颗粒浓度对复合镀层中ZrO_(2)颗粒含量以及复合镀层表面形貌、相结构、硬度、耐磨性能和耐腐蚀性能的影响。结果表明:随着镀液中ZrO_(2)颗粒浓度从5 g/L增加至30 g/L,ZrO_(2)颗粒含量呈现先升高后降低趋势,复合镀层的形貌特征发生变化,导致硬度、耐磨性能和耐腐蚀性能存在差异,但不同复合镀层的相结构无明显差异,都含有单质Zn、Ni_(5)Zn_(21)和ZrO_(2)相。镀液中ZrO_(2)颗粒浓度为20 g/L时,复合镀层中ZrO_(2)颗粒含量达到10.43%,该复合镀层的晶粒细小且结合紧密,表现出良好的致密性,硬度达到503.5 HV,平均摩擦系数和磨损失重仅为0.48和3.42 mg,电荷转移电阻和低频端阻抗值分别达到6.34×10^(3)Ω·cm^(2)和6.84×10^(3)Ω·cm^(2),其性能与Zn-Ni-P合金镀层相比显著提高。适当增加镀液中ZrO_(2)颗粒浓度有利于提高复合镀层中ZrO_(2)颗粒含量,使复合镀层的晶粒明显细化且致密性改善,具有较强的阻碍局部塑性变形和承载能力,并且能有效抑制电化学腐蚀,从而表现出更好的性能。

Tribological behavior of friction stir processed SiP/ZA40 in-situ composites

The effect of friction stir processing(FSP)at different rotation speeds(400,630,800,and 1000 r/min)and traverse speeds(25 and 50 mm/min)on the tribological properties of a Si particle reinforced Zn−40Al−2Cu-based in-situ composite was investigated.After preliminary optimization,800 r/min and 25 mm/min were selected as optimum FSP parameters.According to the results,multi-pass FSP improved the tribological properties.For instance,at an applied pressure of 0.75 MPa,the wear rate and average coefficient of friction(COF)of four-pass FSPed composite were lower than those of base composite by 53%and 50%,respectively.SEM examinations of worn surfaces,wear debris,and worn subsurfaces revealed that the intensive refinement and uniform distribution of microstructural phases,especially the coarse Si particles,reduced Si particles interspacing,and elimination of casting defects were the most important factors enhancing the substrate resistance against sliding-induced deformation.This led to the formation of stable tribolayers that improved the tribological properties.

花状Zn-MOF衍生碳@MoS_(2)复合材料制备及吸波性能

采用Zn-MOF(MOF为金属有机骨架)制备纳米多孔碳材料,通过自组装法将多孔碳与花状MoS_(2)结合,制备出具有规整有序结构的花状Zn-MOF衍生碳@MoS_(2)复合吸波材料。基于Zn-MOF衍生纳米多孔碳的高孔隙率、大比表面积,MoS_(2)的花状结构引起的电磁波多次反射和散射,以及MoS_(2)和Zn-MOF衍生碳之间存在的强极化效应、良好的阻抗匹配和协同作用,Zn-MOF衍生碳@MoS_(2)在频率为9.28 GHz时的最佳反射损耗达到-49.68 dB,表现出优异的电磁波吸收性能。

Preparation and Characterization of Antibacterial Zn^(2+)-Exchanged Montmorillonites

Zn-montmorillonites（Zn-MMTs） as antibacterial compounds were prepared by an ion-exchange reaction. The reaction time, initial pH value and molar ratios of CEC influencing zinc content in Zn-MMTs were investigated, and Zn-MMTs were characterized by means of EDX, XRD, XPS, and SEM. The results of bacterial growth tests were confirmed by determination of the minimum inhibition concentrations （MICs） and minimum bactericidal concentrations （MBCs）. The experimental results show that the zinc is confirmed as bivalent zinc state, the d001 basal spacing of Zn-MMTs is enlarged with the enhancement of the zinc content, and the particles of Zn-MMTs are formed with irregular shape. Moreover, the antibacterial activity of Zn-MMTs increases with increasing the zinc content, and Zn-MMT-3 containing 6.76 mass% of zinc exhibits optimum antibacterial activity against Escherichia coli and Staphylococcus aureus.

Zn-BTC/MoS_(2)复合二维膜构筑及有机溶剂纳滤性能研究

尽管最近兴起的二维膜材料相较于传统的聚合物基膜材料呈现出明显提升的分离性能。但是二维膜中分子传质需要经过层层堆积的二维通道,传输路径较长,限制了二维膜渗透通量的进一步提升。提出用一维金属有机框架纳米线来调控二维膜实现通量提升,同时不降低分离能力。该策略的实现是通过Zn-BTC纳米线插层MoS_(2)层级膜,制备了Zn-BTC/MoS_(2)复合膜。该复合膜的有机溶剂通量比MoS_(2)二维膜提高了2^6倍,丙酮渗透通量高达3562 L·m^(-2)·h^(-1)·bar^(-1)。同时该复合膜保持了与MoS_(2)膜同等优异的筛分能力,对于尺寸大于0.42 nm的染料分子,可以实现100%截留。

膨润土-白泥复合吸附剂处理含Zn^(2+)酸性废水实验研究

为高效处理含重金属Zn^(2+)的酸性矿山废水(AMD),将具有碱性的造纸白泥和具有黏结性和吸附性的膨润土复合,并掺加造孔剂,通过高温焙烧制备新型复合颗粒吸附剂,建立Zn^(2+)的吸附等温式和动力学方程.研究结果表明:复合吸附剂最大碱度释放量为82.9 mg/g(以Ca_(2)CO_(3)计),投加复合吸附剂可使水样的pH值上升.Freundlich等温模型能更好地描述复合吸附剂对Zn^(2+)的吸附,吸附过程更符合准二级动力学方程.