Density Functional Theory Study on the Adsorption of CN on Transition Metal M（100） （M = Ni,Pd, Pt,Cu, Ag and Au） Surfaces

The adsorption of cyanide on the top site of a series of transition metal M（100） （M = Cu, Ag, Au, Ni, Pd, Pt） surfaces via carbon and nitrogen atoms respectively, with the CN axis perpendicular to the surface, has been studied by means of density functional theory and cluster model. Geometry, adsorption energy and vibrational frequencies have been determined, and the present calculations show that the adsorption of CN through C-end on metal surface is more favorable than that via N-end for the same surface. The vibrational frequencies of CN for C-down configuration on surface are blue-shifted with respect to the free CN, which is contrary to the change of vibrational frequencies when CN is adsorbed by N-down structure. Furthermore, the charge transfer from surface to CN causes the increase of surface work function.     

气液分离富集-分光光度法测定固体废物中氰化物的含量

固体废物是指在生产生活中产生的污染环境的固态、半固态废弃物质,按来源大致可分为生活垃圾、一般工业固体废物和危险废物等3种[1-2]。环保部于2007年对危险废物管理名录、危险废物鉴别等标准进行了修订,国家标准GB 5085.3-2007规定氰化物的含量是危险废物鉴别的重要指标之一。氰化物具有高毒性且作用非常迅速,进入人体后会阻断细胞呼吸作用,造成人体缺氧窒息[3-4]。含氰化物的固体废物主要来源于染料、涂料、电镀、化学试剂、医药、冶金工业和合成树脂等行业[5],如果不妥善收集、利用和处理将会污染大气、水体和土壤,进而危害人体健康[6]。     

双金属氰化物在多组分偶联反应中的催化活性(英文)

Several dual metal cyanide catalysts were prepared from potassium ferrocyanide,metal chloride(where metal = Zn2+,Mn2+,Ni2+,Co2+ and Fe2+),t-butanol(complexing agent) and PEG-4000(co-complexing agent).The catalysts were characterized by elemental analysis(CHN and X-ray fluorescence),X-ray diffraction,N2 adsorption-desorption,scanning electron microscopy,Fourier-transform infrared spectroscopy,and UV-Visible spectroscopy.The dual metal cyanide catalysts were used in several acid catalyzed multi-component coup...     

氰根桥联配合物GdFe(CN)6.4H2O的合成、结构及磁性研究

合成了一个氰根桥联Gd(III)离子Fe的三维网状配合物GdFe(CN)6.4H2O。使用元素分析、红外光谱对配合物进行了一般性表征。用X射线衍射法测定了配合物的单晶结构, 属单斜晶系,空间群为C2, 晶胞参数为: a=1.2759(6), b=0.7404(1),c=1.3654(5)nm, β=90.22(3)°, Z=4, 对该配合物进行了变温磁化率测定(4.2-300K)。并使用哈密顿算符(H=-2JS1S2,S1=1/2, S2=7/2)对所测数据进行了理论分析, 求得表征CN^-离子所桥联Gd(III)离子与Fe(III)离子间磁相互作用强弱的磁交换积分J=-69.1cm^-^1, 表明Gd(III)离子与Fe(III)离子间存在有中等强度的反铁磁相互作用。该相互作用是目前已见文献报道的桥联稀土离子和过渡金属离子间发现的最大的磁相互作用。     

饮用水中挥发酚测定方法的改进

目前生活饮用水挥发酚的标准检验方法均采用4-氨基安替比林氯仿萃取光度法，方法采用铁氰化钾作氧化剂，操作过程中产生氰化物污染环境，本文用碘作氧化剂，在硫化氢和二氧化硫含量甚微的情况下，可以不用蒸馏，直接测定方法简单，结果满意。     

金矿含氰废水在土壤中的残留试验

通过对桐柏金矿矿区粘土和南阳一带砂土进行不同浓度下氰化物淋溶试验，并对不同土层风干后氰化物的残留量进行了研究。与原土层土壤本底值氰化物含量进行对比，发现二者并无显著差异。同种土壤经不同浓度的氰化物淋溶后，氰化物残留量也无显著差异。为指导污灌及植物栽培提供了科学依据     

反相流动注射光度法测定矿物浸提液中的游离氰根

１引言以游离氰化物对铜氨络离子的褪色作用来测定游离氰化物的常规流动注射分光光度法已有报道，在生产现场样品量充足，采用反相流动注射分析（ｒＦＬＡ）技术并联用单片机，不仅可以大大节约试剂，而且可以实现程序化自动化操作，节约时间，提高工效，充分体现ＦＬＡ快速分析的特点。这对于生产中所需的在线监测和过程控制是特别适用的。２实验部分２．１仪器装置及参数蠕动泵（自组装）；ＭＣＳ－４８自动采样阀（温州龙方仪器配件厂）；７２１型分光光度计（上海第三分析仪器厂）；ＸＷＴ－１００型台式自动平衡记录仪（上海大华仪表厂…     

THE EXTRACTION OF GOLD FROM CYANIDE SOLUTION BY α—ALKYL SUBSTITUTED PYRIDINE RESIN

In this paper,we have studied the adsorption properties of gold by α-alkyl substituted pyridine resin( BPR) in alkaline solution.The single and dual component kinetic mass transfer process of Au(I),Ag(I) and other metal cyanide ions were also investigated.The results obtained show that the mass transfer rates of the cyanide ions in the resin phase are closely related to the molar ratio and the configuration of metal cyanide ions. The elution kinetics of Au(I) and other cyanide ions by NH4SCN has been investigated systematically.The intraparticle diffusion coefficient and activation energy of Au(I),Ag(I),Ni(I) Fe(Ⅲ） cyanide anions were determined in CI,NO3,OH-type BPR resin at different temperatures.It is found from the experimental results that the mechanism for extracting Au(I),Ag(I) and other metal cyanide anions by BPR resin belongs to ion exchange process.The difference of activation entropy of some metal cyanide anions(ΔS-ΔS^-) was evaluated.     

涂丝Ag-Ag2S电极测定水体中微量氰化物的研究

本文报道了涂丝Ag-Ag2S电极测定水体中微量氰化物(CN-)的分析方法。该方法对现用的Ag(CN)2-指示剂配制方法以及使用浓度作了新的改进,加之成功地在ISAB中引入有机溶剂等,较大程度地提高了测定CN-的灵敏度。该方法测定CN-的线性范围为1.0×10-3～1.0×10-7mol/L,检出限可达4.0×10-8mol/L,标准偏差小于0.015,回收率为99%～104%。本方法与比色法对照,相对误差≤1.3%,结果令人满意。