三乙醇胺对全钒液流电池正极电解液的影响

通过热稳定性考察、紫外-可见吸收光谱、循环伏安和充放电测试,研究了三乙醇胺作为全钒液流电池正极电解液添加剂对电化学活性和5价钒电解液热稳定性的影响.实验结果表明,三乙醇胺对电解液的热稳定性有较大的提高,5价钒离子浓度在50℃下保存12h后仍有1.08mol/L,高于空白电解液的0.16mol/L.由可紫外-可见吸收光谱可知,三乙醇胺的加入没有改变钒的成键方式.同时,三乙醇胺对正极电解液的电化学活性和可逆性也有提高,有更高的峰电流和更小的峰电位差,组装的电池前30个循环平均能量效率可达80.4%,高于空白电池的1.4%.     

河南省淅川西簧矿区钒矿床的地质特征及找矿标志

西簧钒矿位于河南省淅川县境内,大地构造隶属于淅川-内乡钒多金属矿带。矿床赋存地层为寒武系黑色岩系。矿床分为东西两段,由三个矿体组成,通过对矿区内钒矿地质特征以及找矿标志的研究可知,西簧钒矿床的成因类型属潮坪泻湖相沉积石煤（或炭质页岩）型钒矿床,西簧钒矿钒的典型地层标志为水沟口组中下段炭质页岩、石煤层以此为例,对于探寻相同类型的钒矿起到了一定的指导作用。     

高铬型钒钛磁铁矿烧结试验

在高铬型钒钛磁铁矿基础特性研究的基础上,进行了配矿优化和烧结杯试验,并对烧结产物进行显微分析.结果表明,该矿烧结基本特性差,随着配比的提高,垂直烧结速度和产品转鼓指数下降,成品率和利用系数先升后降.另外,显微结构分析表明,高铬型钒钛烧结矿矿物组成主要有磁铁矿、赤铁矿、钙钛矿、铁酸钙、硅酸二钙和玻璃质.随着该矿配比的提高,烧结矿中铁酸钙、硅酸二钙含量降低,钙钛矿及玻璃相含量增加,液相量不足.因此,在实际生产中,该矿配比宜控制在10%~20%之间.     

Permeation of vanadium(III,IV,V)-dipicolinate complexes across MDCK cell monolayer and comparison with Caco-2 cells

In resent years, great attention has been paid to the in-sulin-mimetic property of various vanadium compounds. Although the mechanism of the hypoglycemic effect of vanadium compounds has not been elucidated, the major problems limiting further clinical applications for inor-ganic vanadium compounds include low oral absorption (<10%)[1] and gastrointestinal stress[2―5]. Hence, a series of vanadium complexes with organic ligands have been syn-thesized, such as bis(maltolato) oxovanadium(IV) (V…     

溶胶-凝胶法制备复合钒钼酸干凝胶薄膜及表征

利用无机溶胶—凝胶法制备复合钒钼酸H     

湿法提取石煤中钒的新工艺研究

采用分段溶解法提取石煤中的五氧化二钒，浮选去除石煤中大部分碳后，先在稀盐酸介质中溶解氧化物中的钒，然后用盐酸和亚铁盐浸取硅铝酸盐中钒，使大部分钒转入溶液中，浸出液经氧化处理料液后，料液经过离子树脂交换，一次提取即可获得纯度达97.0%的五氧化二钒产品，钒回收率在85%以上。     

良好结晶VO2(A)纳米杆的相变、电学和光转变特性

在VO2-草酸体系中,利用一步水热合成法制备结晶良好的VO2(A)纳米杆.成品的结构和尺寸分别通过X射线衍射(XRD)、扫描电镜(SEM)和透射电子显微镜(TEM)表征.差示扫描量热(DSC)曲线显示在加热过程中VO2的相转变温度为167.8 ℃.变温X射线衍射(XRD)图谱显示加热时VO2(A)在160~180 ℃发生相变.温度升高到450 K时,磁化率突然增加.使用4探针法测量VO2(A)样品的电阻率,滞后现象显示VO2(A)的相变为1级相变.根据阿仑尼乌斯曲线,得出低温VO2(AL)和高温VO2(AH)的活化能分别为0.39 eV和0.37 eV.变温红外光谱显示VO2(A)纳米杆在红外区域具有良好的光学转换特性,此特性与VO2(A)的可逆结构转变有关.研究结果表明VO2 (A)纳米材料可应用于红外开关装置.     

钒元素对压力容器用低合金铬钼钢力学性能的影响

通过对2．25Cr1Mo、2．25Cr1Mo0．25V、2．25Cr1Mo0．3V3种不同类型的铬钼钢进行化学分析、冲击韧性试验和拉伸试验，就钒元素对压力容器用低合金铬钼铜的力学性能的影响进行了探讨．结果表明，铬钼钢中随着钒元素的加入和含量的增加，晶粒得到明显的细化，抗拉强度由570MP提高至620MP，伸长率由27％变为24％，冲击功由270J提升至330J，材料的强度和韧性得到明显提高，但是塑性随着钒元素的加入和含量增加而略有下降．试验结果为大型厚板压力容器的制造提供了参考依据．     

Adsorption properties of V(Ⅳ) on resin-activated carbon composite electrodes in capacitive deionization

Composite electrodes prepared by cation exchange resins and activated carbon (AC) were used to adsorb V(Ⅳ) in capacitive deion-ization (CDI). The electrode made of middle resin size (D860/AC M) had the largest specific surface area and mesoporous content than two other composite electrodes. Electrochemical analysis showed that D860/AC M presents higher specific capacitance and electrical double layer capacitor than the others, and significantly lower internal diffusion impedance. Thus, D860/AC M exhibits the highest adsorption capacity and rate of V(Ⅳ) among three electrodes. The intra-particle diffusion model fits well in the initial adsorption stage, while the liquid film diffusion model is more suitable for fitting at the later stage. The pseudo-second-order kinetic model is suited for the entire adsorption process. The ad-sorption of V(Ⅳ) on the composite electrode follows that of the Freundlich isotherm. Thermodynamic analysis indicates that the adsorption of V(Ⅳ) is an exothermic process with entropy reduction, and the electric field force plays a dominant role in the CDI process. This work aims to improve our understanding of the ion adsorption behaviors and mechanisms on the composite electrodes in CDI.     

Solid-state reaction of a CaO?V2O5 mixture: A fundamental study for the vanadium extraction process

The aim of this study was to investigate the phase transformation and kinetics of the solid-state reaction of CaO?V2O5, which is the predominant binary mixture involved in the vanadium recovery process. Thermal analysis, X-ray diffraction spectroscopy, scanning electron microscopy, and energy dispersive spectrometry were used to characterize the solid-state reaction of the samples. The extent of the solid reac-tion was derived using the preliminary quantitative phase analysis of the X-ray patterns. The results indicate that the solid reaction of the CaO?V2O5 mixture is strongly influenced by the reaction temperature and CaO/V2O5 mole ratio. The transformation of calcium vanadate in-volves a step-by-step reaction of CaO?V2O5, CaO?CaV2O6, and CaO?Ca2V2O7 depending on the CaO/V2O5 mole ratio. The kinetic data of the solid reaction of the CaO?V2O5 (1:1) mixture followed a second-order reaction model. The activation energy (Ea) and preexponential factor (A) were determined to be 145.38 kJ/mol, and 3.67 × 108 min?1, respectively.