陶瓷原料中SiO_2的钼酸银沉淀法测定

通过实验,发现络合滴定用的指示剂——偶氮胂—Ⅲ,可用作本测定中的沉淀滴定指示剂。根据标准 AgNO_3溶液同 MoO_4~(2-)的定量反应,计算出以硅钼黄 Hg[Si(Mo_2O_7)_6]形式存在的MoO_4~(2-)量,再据以算出硅酸盐中 SiO_2的含量。     

石墨粉镀银新工艺研究

研究了镀液中硝酸银浓度、石墨粉加入量和阴极电流密度等工艺条件对镀银石墨粉含银量和电镀效果的影响。用扫描电镜对镀银石墨粉的微观形貌和镀覆效果进行分析，通过X射线衍射仪对镀银石墨粉高温灼烧后的剩余物进行分析测试并计算镀银石墨粉的含银量。研究结果表明：采用惰性电极作为电镀阳极，在化学镀预处理过的石墨粉表面可成功镀覆一层银，其含银量达76%。     

Propagation of the Chain Explosive‐Decomposition Reaction in Silver Azide Crystals

The velocity of the chain explosivedecomposition reaction in silver azide whiskes has been measured (1500 m/sec). The measured velocity is identified as the propagation velocity of the diffusion front of holes generated in the course of explosive decomposition.     

Electrodeposition of silver from nitrate solution: Part II. Mechanism of the effect of phosphate ions

The mechanism of compact Ag-film formation by electrolysis from nitrate solution with addition of small amounts of phosphate ions is elucidated. It is shown that the phosphate ions exert their effect by lowering the exchange current density. Consequently, the radii of nucleation exclusion zones also diminishes, thus producing conditions stimulating electrodeposition of continuous thin Ag-film.     

Use of electrodialysis to remove silver ions frommodel solutions and wastewater

The feasibility of the removal of Ag⁺ ions in a model solution and a sample of rinse water provided from an industrial plating plantwas investigated in a batch electrodialysis system. The experiments were carried out using two different types of ion-exchange membranes. The effects of applied potential, pH value and initial silver concentration on the duration of electrodialysis and energy consumption were examined. Full removal of Ag+ ions was achieved from model solutions and the sample of rinse water. The most convenient applied voltage and energy consumption values to remove silver ions are reported. These results will be useful for designing and operating different capacities of electrodialysis plants for recovering Ag⁺ ions.     

Synthesis of fluorine-graphite intercalation compounds by elemental fluorine and high oxidation-state transition-metal fluorides

Fluorine-graphite intercalation compounds have been synthesized using high purity fluorine gas and high oxidation-state transition-metal fluorides, AgF₃ and NiF₃, at room temperature and at −78 °C. At room temperature, a mixture of stage 1 + 2 − 4 compounds with compositions, C_4.2F to C_14.6F were obtained. On the other hand, stage 2–4 compounds with compositions C_5.6F to C_14.2F were synthesized at −78 °C. The fluorinating ability of AgF₃ and NiF₃ has been shown more clearly at room temperature because a small amount of fluorine was intercalated/absorbed into graphite at −78 °C without catalysts. XPS spectra show that ionic, nearly ionic, semi-covalent and covalent fluorines coexist in the C_xF samples, and that the covalency of CF bonding increases with decreasing stage number.     

含氯离子废水化学需氧量分析方法比较

含氯离子废水化学需氧量的分析方法的研究是当前环境监测研究的热点之一，各种文献报道也较多，但各自使用的效果不一。采用试验的方法对含氯离子废水中CODCr的分析进行了初步研究，比较了硫酸汞加入法、稀释法、硝酸银滴定法、氯气校正法、氯离子校正法等方法在不同化学需氧量不同氯离子浓度下的分析结果，利用分析结果与配置的标准溶液浓度相比较，分析了各种方法的优缺点，结果表明硝酸银滴定法是比较理想的适应范围较广的方法。     

氮三甲撑膦酸中氯离子含量测定方法的研究

在酸性条件下,用Ag~ 沉淀氮三甲撑膦酸溶液中的Cl~-,然后以淀粉和KIO_3为指示剂,用标准I~-溶液滴定过量的Ag~ 。测定准确,方法灵敏,可靠和方便。克服了莫尔法和佛尔哈德法不适用于该测定体系的困难。     

非金属电镀用导电漆的研制

介绍了导电漆、作为导电填料的片状镀银铜粉的制备工艺流程。分别研究了漆膜表面单位电阻与镀银铜粉的含量及其粒径以及钛酸酯偶联剂的含量之间的关系。结果表明,当镀银铜粉的粒径为400目、质量分数在57%~65%之间,钛酸酯偶联剂的质量分数为10%时,所得涂膜的导电性能最佳。加入含C-18的油酸可以使导电漆长期贮存而电阻值不变。经检测,所得涂膜具有良好的性能:附着力1级,硬度1 H,柔韧性1 mm,冲击强度50 kg/cm2,膜厚10~15μm,漆膜表面每厘米电阻0.15Ω,每分米电阻0.47Ω。指出了导电漆应用过程中的注意事项。     

高锰高砷硫化银精矿湿法提银扩大试验

以广西凤凰高锰高砷硫化银精矿为原料,进行了全湿法提银扩大试验,结果表明银的直收率和总回收率达到91 59%和95 67%;锰和铅回收率分别为99 18%和87 41%;粗银粉和铅精矿品位分别为32 565%和72 43%。同时该工艺防止了硫、砷、铅等有毒元素对环境的污染,脱锰产生的H2S经两级碱吸收即全部以Na2S·9H2O的形式回收。