JEE—4x型真空镀膜仪功能扩展

报道了对ＪＥＥ－４ｘ型真空镀膜仪蒸发装置的改进以及建立蒸发材料回收装置的具体方法，并介绍了改进后该仪器在高分辨扫描电镜样品制备上的应用实例．实验证明，上述改进不但扩展了ＪＥＥ—４ｘ型真空镀膜仪的制样功能又节省了蒸发材料，集中了离子溅射法及常规高真空镀膜法的优点，完全满足ＳＥＭ样品的分析要求，该方法简单易操作．     

苯甲酸钠团簇离子的形成和结构

用串级飞行时间质谱(Tandem TOF)仪研究了激光蒸发方法产生的苯甲酸钠及裂解产物团簇离子的形成和可能的构型。通过对苯甲酸钠团簇离子的紫外光解的研究, 决定了反应通道及分支比, 并定性地讨论了其结构特征。     

电热蒸发-电感耦合等离子体质谱(ETV-ICP-MS)技术中气溶胶传输效率研究进展

蒸发效率和传输效率是影响电热蒸发-电感耦合等离子体质谱(ETV-ICP-MS)技术分析性能的关键因素。综述有关气溶胶传输效率的研究进展,在归纳常用的传输系统评价方法的基础上,重点对影响气溶胶传输效率的电热蒸发装置的改进、蒸发过程的探讨、基体改进剂的选择等研究现状进行评述。有关ETV蒸发过程中基体干扰的作用机制仍有待进一步系统研究,这对于校正策略的优化、新型校正技术的创新与集成具有重要的理论指导意义,可推动ETV-ICP-MS在地质、环境、生物等学科的更广泛应用。     

流动注射壳聚糖在线微柱预富集电热原子吸收光谱法测定痕量Cr(Ⅵ)

以天然高分子材料壳聚糖作在线预富集柱填料,流动注射与电热原子光谱联用测定痕量Cr(Ⅵ).采样体积5.80mL,采样频率22样/h,富集倍数51倍,线性范围0.02μg/L～0.12μg/L,该方法的检出限(3s,n=11)0.69ng/L,相对标准偏差5.1%(CCr(Ⅵ)=0.10μg/L,n=11).将该方法用于环境水样、茶叶样品和头发样品中Cr(Ⅵ)的测定,结果满意.     

氨蒸发诱导法制备纳米结构LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2及其作为高功率型锂离子电池正极材料的性能

采用氨蒸发诱导法成功制备出纳米结构LiNi1/3Co1/3Mn1/3O2正极材料,借助X射线衍射(XRD)分析、扫描电镜(SEM)、透射电镜(TEM)、高分辨率透射电镜(HRTEM)、能量分散谱(EDS)和比表面测试等表征手段及恒电流充放电测试研究了其晶体结构、微观形貌和电化学性能.研究表明该方法制备出的材料具有良好的α-NaFeO2层状结构,阳离子混排程度低.纳米片交错堆积而成核桃仁状形貌,片与片之间形成许多纳米孔,而且纳米片的侧面属于{010}活性面,能够提供较多的锂离子的脱嵌通道.在室温下及3.0-4.6 V充放电范围内,该材料在电流密度为0.5C、1C、3C、5C和10C时放电比容量分别为172.90、153.95、147.09、142.16和131.23mAh?g-1.说明其具有优异的电化学性能,非常有潜力用于动力汽车等高功率密度锂离子电池中.     

离子对反相高效液相色谱法分离伊班膦酸钠及其有关物质

采用离子对反相高效液相色谱法研究了伊班膦酸钠及其有关物质的色谱分离方法。以Inertsil C8色谱柱为固定相,乙腈．甲醇．12mmol／L乙酸铵缓冲液（含35mmol／L正戊胺,pH7．0）（8：4：88）为流动相,流速为1．0mL／min,分析物以通用型的蒸发光散射检测器（ELSD）测定。在该色谱条件下,伊班膦酸钠及其有关物质分离良好且能够被同时检测。本方法采用的可挥发离子对试剂和缓冲液的流动相系统,同时解决了伊班膦酸钠及其有关物质的分离与检测的问题,简单快速、专属性强,适用于伊班膦酸钠的有关物质检测,为该药的质量控制提供了简便可靠的分析手段。     

MgSO4-Na2SO4-H2O三元体系100 ℃沸腾蒸发非平衡态成盐特征

采用140 ℃恒温热源, 对MgSO4-Na2SO4-H2O体系溶液进行100 ℃恒温沸腾蒸发, 蒸发强度为140～160 g/(h•L), 监测初始析盐点和固相析出后固液相组成随蒸发进程的变化, 总结成盐特征, 提出反映非平衡态成盐特征的初级成盐区、扩展成盐区等概念. 研究发现(1)平衡相图上的同成分复盐3Na2SO4• MgSO4和Na2SO4• MgSO4•2.5H2O变为异成分复盐; (2)对Na2SO4和3Na2SO4•MgSO4的平衡共饱和液蒸发, 首先析出的是Na2SO4, 其单固相析出率为60.86%, 3Na2SO4•MgSO4和Na2SO4•MgSO4•2.5H2O的共饱和液也具有相同特征; (3)蒸发过程的初级成盐区与溶解平衡相区有显著区别. 用硫酸钠的耶涅克指数表示相区宽度, Na2SO4初级成盐区宽度从平衡态的21.02扩大到32.76; 而Na2SO4•MgSO4•2.5H2O则从41.40缩减为25.71; (4)在晶种存在的条件下, 各种盐的成盐区比初级成盐区有不同程度的扩展, 如Na2SO4, 3Na2SO4•MgSO4等盐的成盐区分别扩展了7.72和8.81. 扩展成盐区与初级成盐区的交叠形成了非平衡条件下特有的条件成盐区, 析盐种类取决于晶种的种类.     

Temperature and metal composition dependence of lateral photovoltaic effect in Al-Alq3/SiO2/Si structures

A series of Al=-（Alq3）l-x granular films is prepared on Si wafer with native oxide layer using co-evaporation technique. Large lateral photovoltaic effect （LPE） is observed, with an optimal LPV sensitivity of 75 mV/mm in x=0.35 sample. The dependence of LPE on temperature and A1 composition is investigated, and the possible mechanism is discussed.     

Controllable synthesis,characterization,and growth mechanism of hollow Zn_x Cd_(1-x) S spheres generated by a one-step thermal evaporation method

Novel hollow ZnxCdl xS spheres that are uniform in size are synthesized through the one-step thermal evaporation of a mixture of Zn and CdS powder. From an X-ray diffraction （XRD） study, the hexagonal wurtzite phase of ZnxCdl_xS is verified, and the Zn mole fraction （x） is determined to be 0.09. According to the experimental results, we propose a mechanism for the growth of Zn0.09Cd0.91S hollow spheres. The results of the cathodoluminescence investigation indicate uniform Zn, Cd, and S distribution of alloyed Zn0.09Cd0.91S, instead of separate CdS, ZnS, or nanocrystals of a core- shell structure. To the best of our knowledge, the fabrication of ZnxCd1-xS hollow spheres of this kind by one-step thermal evaporation has never been reported. This work would present a new method of growing and applying hollow spheres on Si substrates, and the discovery of the Zn0.09Cd0.91S hollow spheres would make the investigation of ZnxCd1-xS micro/nanostructures more interesting and intriguing.     

石墨烯玻璃透明薄膜加热特性

Graphene has become a research focus in recent years owing to its excellent characteristics, and glass is a commonly used material with high transparency and low cost. Graphene glass combines the excellent properties of both graphene and glass; graphene glass has not only high thermal conductivity, high electrical conductivity, and good surface hydrophobicity but also exhibits superior electrothermal conversion and wide-spectrum high-light-transmittance characteristics. Therefore, the study of graphene glass films is of theoretical value and practical significance. In this study, a high-purity glass-based (JGS1 quartz glass) multilayer graphene film was developed based on an atmospheric-pressure chemical vapor deposition (APCVD) method, and its electrical characteristics, light transmittance, and electrical heating characteristics were experimentally investigated in detail. The results show that graphene glass with different surface resistance values obtained through direct growth on a high-purity quartz glass substrate using the APCVD method, not only has excellent uniformity and quality, but also has considerably flat and high transmittance across the entire visible light region and exhibits excellent heating performance and fast response time. For graphene glass with a surface resistance of 1500 Ω·sq^-1, the light transmittance can reach 74%, and the saturation temperature can rise to 185 ℃ by applying a bias voltage of 40 V. In addition, when the resistance value of the graphene glass is 420 Ω·sq^-1, the graphene glass reaches a high saturation temperature of 325 ℃ in 40 s, and the corresponding heating rate can exceed 18 ℃·s^-1, achieving a significantly higher heating rate than other heating films at the same voltage. Compared with the polyethylene-terephthalate- (PET-) based and silicon-based graphene films obtained by the transfer, graphene glass has a higher saturation temperature, shorter thermal response time, and faster heating rate. Furthermore, graphene glass exhibits better heating cycle stability and longer-term heating stability at a constant voltage. In addition, an experiment using the graphene glass to thermally tune the wavelength of a vertical-cavity surface-emitting laser was conducted and gave good results. The position of the laser peak controlled by the graphene glass was red-shifted by 1.78 nm by applying a voltage of 20 V, and the wavelength tuning efficiency reached 0.059 nm·℃^-1. Compared with PET-based and silicon-based graphene films, the actual electrical heating capacity of graphene glass increased by 195%. These experimental findings demonstrate that graphene glass transparent films with excellent electric heating characteristics can be used in various transparent electric heating fields and have relatively wide application prospects.