催化褪色光度法测定粉煤灰中痕量钼(Ⅵ)

在0.01 mol/L H2SO4介质中,痕量钼(Ⅵ)对过氧化氢氧化乙基紫(EV)的褪色反应具有强烈的催化作用,据此建立了测定痕量钼(Ⅵ)的催化光度新方法。对反应介质、试剂用量、反应温度、反应时间及干扰离子的影响等进行了探讨,并确定了最佳反应条件。研究表明,体系的最大吸收波长为590 nm,钼(Ⅵ)质量浓度在0~500μg/L内符合比尔定律,方法的检出限为0.11μg/L。方法可直接用于粉煤灰中钼(Ⅵ)的测定,结果与分光光度法相符,6次测定值的RSD<3%。     

粉煤灰中痕量钴的催化光度法测定

基于在 pH1 0.0的Na2 B4O7-NaOH介质中 ,痕量Co 催化H2 O2 氧化桑色素的褪色反应 ,褪色程度与Co 量在 0.0～ 50.0 μg/L范围内呈线性关系 ,建立了一种测定痕量Co 的光度法。方法的检出限为 7.6× 1 0 -11g/mL。结合N5 3 0 萃取剂萃取分离 ,测定了粉煤灰中的微量钴。     

铍试剂Ⅲ褪色光度法测定痕量钼的研究

在pH11.92Britton Robinson(B R)缓冲溶液存在和加热条件下,基于钼催化过氧化氢氧化铍试剂Ⅲ(berylliumⅢ,以下简称BLⅢ)的反应建立了测定痕量钼的新方法。催化反应动力学方程为:-dCBLⅢ/dt=k′[BLⅢ]·[H2O2]·[Mo ],表观速率常数k′=2.1×10-3s-1,表观活化能E′=67.5kJ·mol-1,方法的线性范围是0.05～15μg/L,检出限为0.35μg/L,方法已用于水体、绿豆等样品中痕量钼的测定。     

溴酸钾氧化双硫腙催化光度法测定矿样中痕量钯(Ⅱ)

在非离子表面活性剂TritonX-100存在下,在磷酸介质和加热的条件下,痕量钯(Ⅱ)对溴酸钾氧化双硫腙的褪色反应具有显著催化作用,且褪色程度与Pd(Ⅱ)量在一定范围内呈线性关系,据此建立了一种测定痕量钯(Ⅱ)的催化光度法。结果表明:褪色溶液的最大吸收波长为410 nm,方法的线性范围为0-60μg/L,检出限为4.42×10-7g/L。方法已用于矿样中痕量钯的测定,相对标准偏差小于4%,回收率为98.6%-102.0%。     

阻抑甲基红褪色光度法测定土壤及废水中铬(Ⅵ)

在硝酸介质中,加热条件下甲基红褪色,铬(Ⅵ)能显著阻抑此褪色反应,据此建立了测定痕量铬(Ⅵ)的新方法。有色溶液的最大吸收波长在520nm处,方法检出限为3.41×10-10g/mL,线性范围0～0.25μg/10mL,用于土壤及废水中痕量铬(Ⅵ)的测定,结果满意。     

重铬酸钾氧化偶氮胂Ⅲ褪色光度法测定铂

在微酸性介质中痕量铂（Ⅳ）对重铬酸钾氧化偶氮胂Ⅲ褪色反应有显著的催化作用,建立了测定痕量铂（Ⅳ）的催化动力学光度法。方法的检出限为0．31μg/L,线性范围为0．31－20μg/L,可用于含铂催化剂及矿石中铂的测定。     

橙黄G-高碘酸钾催化动力学体系光度法测定痕量铁

在硫酸介质中 ,微量铁 能显著催化高碘酸钾氧化橙黄G(OG)的褪色反应。研究了该催化褪色反应的最佳反应条件和动力学参数 ,建立了催化动力学测定痕量铁的新分析方法。本方法测定铁的线性范围为 0.0 0 0 2～ 0.0 3 2 μg/mL ,检出限为 5.3 4× 10 - 1 0 g/mL。用本法测定了中草药及食品中铁的含量 ,结果满意     

抑制-褪色光度法测定痕量铬(Ⅵ)的研究

基于稀H2 SO4 介质中痕量Cr(Ⅵ )对KBrO3 氧化 2 (5 溴 2 吡啶偶氮 ) 5 二乙氨基酚褪色反应的阻抑作用 ,建立了测定痕量Cr(Ⅵ )的动力学光度法 ,方法检出限为 0 6 2 μg/L ,线性范围为 0 6 2～ 40 μg/L。用于测定环境水样中的痕量Cr(Ⅵ ) ,结果满意     

催化动力学光度法测定痕量铒

研究了在氨水 氯化铵缓冲溶液中痕量铒催化过氧化氢氧化溴甲酚紫褪色的指示反应及其动力学条件 ,从而建立了一种新的测定铒的方法 ,该方法的灵敏度为 1 46× 10 -10 g/ml,测定线性范围为 0～ 0 4μg/ 10ml     

电感耦合等离子体串联质谱法测定高纯钼中痕量镉

高纯钼中痕量镉因受到钼氧、钼氮等多原子离子的严重干扰,即使采用高分辨质谱仪也无法准确分析。为了有效消除干扰,采用串联质谱的反应池技术,选取¹¹¹Cd为分析同位素,分别在H₂和NH₃模式下讨论了1000μg/mL Mo标准溶液和1000μg/mL Mo-1.000ng/mL Cd混合标准溶液的信号强度以及背景等效浓度(BEC)的变化趋势,并优化了气体流速;最终选择0.4mL/min的NH₃做反应气,此时1000μg/mL Mo标准溶液中Cd的背景等效浓度约为0.8ng/L,表明钼氧、钼氮等多原子离子对Cd的干扰可被有效地消除。在选定的仪器测试条件下,校准曲线的线性相关系数大于0.9999,方法检出限为2.7ng/g,加标回收率为93%~105%。采用所建立的电感耦合等离子体串联质谱(ICP-MS/MS)测定高纯钼中痕量镉的方法分析高纯钼样品,测得结果的相对标准偏差(RSD,n=5)为0.50%~4.2%。     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

China's Major Non-ferrous Metals Imports & Exports

正~~     

Zinc Production by Province in 2014

正~~     

80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.