催化动力学示波电位法测定蔬菜中痕量钒

研究了在酸性介质中 ,钒催化KBrO3 KBr 抗坏血酸体系的反应和动力学条件 ,建立了催化动力学示波电位法测定痕量钒的方法。该方法的检出限为 0 .0 1 1 5μg·ml- 1 ,线性范围为 0～ 0 .1 0 3μg·ml- 1 ,反应的活化能为 1 5 .30kJ·mol- 1 。该法加料测定回收率为 96 %～ 1 0 1 % ,操作简便、快捷 ,准确度高。用于蔬菜中钒的含量测定 ,结果令人满意。     

偶氮胂-M催化动力学光度法测定痕量锡

基于 0 .0 8mol·L- 1 的H2 SO4 介质中 ,痕量锡催化溴酸钾氧化偶氮胂 M的褪色反应 ,建立了测定痕量锡的催化光度法。方法检出限为 0 .2 2 μg·L- 1 ,线性范围为 0 .2 2～ 8.0 μg·L- 1 。结合磷酸三丁酯色谱分离 ,用于测定环境水样、人发及岩石样品中的痕量锡。     

过氧化氢氧化二氯荧光素动力学荧光法测定痕量镍

在近中性介质中,痕量镍(Ⅱ)对过氧化氢氧化二氯荧光素的反应具有很强的催化作用,当加入痕量镍(Ⅱ)时,可使反应体系的荧光强度减小,据此建立了催化动力学荧光法测定痕量镍(Ⅱ)的新方法。反应体系的激发波长和发射波长分别为491 nm和517 nm,测定镍(Ⅱ)的线性范围为4.0~80.0μg/L,检出限为2.4μg/L。该法用于废水中痕量镍(Ⅱ)的测定,加标回收率为103.6%。     

催化显色光度法测定痕量钯

在H3PO4 介质和 90℃水浴条件下 ,痕量钯 (Ⅱ )对溴酸钾氧化二安替比林对二乙氨基苯基甲烷 (DAEAM)的显色反应具有显著催化作用 ,研究了反应的最优化条件 ,并测定了一些动力学参数 ,据此建立了催化动力学光度法测定痕量钯 (II)的新方法。方法的线性范围为 0 .0～ 1.6和 1.6～ 4.4μg·L- 1 ,检出限为 8.4× 10 - 8g·L- 1 ,表观活化能为 91.67kJ·mol- 1 。     

过氧化氢氧化核固红催化荧光法测定痕量钴的研究

在硼砂 氢氧化钠缓冲溶液中 ,钴 (Ⅱ )对过氧化氢氧化核固红的反应具有强烈的催化作用 ,建立了催化荧光法测定痕量钴 (Ⅱ )的新方法。此法的线性范围为 0 .16～ 3 .2 μg·L- 1 ,检出限为 5 .0× 10 - 1 1 g·ml- 1 。用于维生素B1 2 、茶叶及人发中痕量钴的测定 ,取得了满意的结果。     

双指示剂催化光度法测定痕量镍

研究了在氨水介质中,痕量镍(Ⅱ)催化高碘酸钾氧化吖啶红和靛蓝胭脂红褪色的指示反应,通过测量530 nm和610 nm处催化反应体系和非催化反应体系吸光度的变化,建立了双波长双指示剂催化动力学光度法测定痕量镍的新方法。在最佳实验条件下,镍的质量浓度在0~0.04μg/mL范围内与ΔΑ存在线性关系(ΔΑ=ΔΑ530+ΔΑ610),线性方程为ΔA=17.10ρNi2+(μg/mL)-0.001 1,r=0.997 2,方法检出限为0.061μg/L。该方法用于合金中痕量镍的测定,与标准样品含量基本一致。     

催化动力学光度法测定痕量钴的研究

研究了在氨水溶液介质中,以氯化钾溶液为活化剂,痕量钴离子催化过氧化氢氧化溴甲酚紫褪色的指示反应,通过测量590 nm处溶液吸光度的改变,建立了催化动力学光度法测定痕量钴的新方法。在最佳实验条件下,该方法测定钴离子的线性范围为0.00~0.048μg.ml-1,检出限为1.6×10-10g.ml-1。对0.040μg.ml-1Co2+进行10次平行测定的相对标准偏差为3.8%。用于维生素B12中钴的测定,回收率为97.23%。该方法灵敏度高、体系稳定、重现性好。     

过氧化氢氧化亚甲基蓝褪色催化光度法测定铝合金中痕量镍

基于在pH 5.6的Na₃C₆H₅O₇-NaOH缓冲溶液中,痕量镍对H₂O₂氧化亚甲基蓝(MB)的褪色反应具有催化作用且褪色的程度与镍的含量成线性关系,建立了催化动力学光度法测定痕量镍的新方法。研究了影响催化褪色反应的因素,并测定了一些动力学参数。结果表明,非催化反应体系与催化反应体系的最大吸收波长均在664 nm处,方法的线性范围为0.02～1.4 μg/mL,线性回归方程为lg(A₀/A_t)=0.776 5 ρ(μg/mL)+0.157 1,相关系数r =0.998 6,检出限为0.011 8 μg/mL,反应的表观活化能为25.14 kJ/moL。方法用于铝合金标准样品中痕量镍的测定,结果与认定值基本一致,相对标准偏差(RSD)为2.9%和2.8%(n=5),回收率在98%～104%范围。     

水杨醛肟催化光度法测定煤矸石中痕量锰

研究了在NH3·H2 O -NH4 Cl缓冲溶液中痕量锰 催化过氧化氢氧化水杨醛肟 (SAO)的显色反应 ,催化程度与Mn 量在一定范围内呈线性关系。借此建立测定痕量Mn 的催化光度法。结果表明 ,有色溶液的最大吸收波长为 410nm ,方法检出限为 1.2× 10 -11g/mL ,催化程度与Mn 量在 0～ 0.30 μg/2 5mL范围内符合比尔定律 ,可用于测定煤矸石中的痕量锰     

过氧化氢氧化亚甲基蓝褪色催化动力学光度法测定镍

在pH 8.00的NH₃-NH₄Cl缓冲溶液中,在100 ℃加热条件下,痕量镍能催化过氧化氢氧化亚甲基蓝的褪色反应,建立了测定痕量镍的催化动力学光度方法。研究发现,非催化反应吸光度(A₀)和催化反应吸光度(A)在655 nm处的差值ΔA与镍的质量浓度在0.01～0.30 μg/mL范围内呈良好的线性关系,方法检出限为8.6×10^-3 μg/mL。该催化反应的表观速率常数为8.2×10^-4 s^-1,表观活化能为66.08 kJ/mol。方法用于延河水和自来水厂污水中痕量镍的测定,测定值与原子吸收光谱法一致,相对标准偏差(RSD,n=6)为1.2%～1.6%,加标回收率为99%~102%。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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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.     

Seven Rare Earth Projects Involving Close to 3 Billion Yuan Investment Landed In the HighTech Zone

正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.