电感耦合等离子体光谱法测定镍基高温合金中的硅、锰、磷

建立了电感耦合等离子体光谱测定镍基高温合金中硅、锰、磷元素的方法,优化了试样前处理方法,对前处理所用酸的酸度进行不同比例试验,确定了仪器测量条件及分析谱线.在一定浓度范围内,各元素的浓度与谱线强度呈线性关系,相关系数大于0.9999.加标回收率为93.3%～106.7%,测定结果的相对标准偏差小于3.0%(n=10)....     

电感耦合等离子体发射光谱法测定铝合金中硅、锰、铬

采用电感耦合等离子体发射光谱法测定铝合金中杂质元素硅、锰、铬的含量.以盐酸溶液(1+1)和过氧化氢溶解样品,选择各元素灵敏度较强、光谱干扰较小的波长作为分析线.3种杂质元素的发射强度与其质量浓度在20.00 mg/L以内呈线性关系,方法的检出限为0.0016～0.015 mg/L,测定结果的相对标准偏差为1.10％～2...     

SYNTHESIS,CRYSTAL STRUCTURE AND MAGNETIC PROPERTIES OF A MANGANESE(III) COMPLEX WITH SALICYLATE AND IMIDAZOLE LIGANDS

Abstract

A new manganese(III) complex [HimH][Mn(sal)₂(imH)₂]CH₃OH (sal = salicylate, C₇H₄O₃ ^2-; imH = imidazole, C₃H₄N₂; [HimH]⁺ = imidazole cation (C₃H₅N₂) has been prepared and characterized by X-ray analysis and magnetic measurements. The compound crystallizes in the monoclinic space group P2 ₁ with a = 9.931(2), b = 10.237(1), c = 12.926(7) Å, β = 102.740° and Z = 2. The structure has been refined to R = 0.030 and R_w = 0.031. The Mn(III) ion has elongated octahedral coordination with mutually trans imidazoles occupying axial sites. The equatorial plane is defined by four O atoms of two salicylates. Each [HimH]⁺ cation (imidazolium) is associated with two complex anions through hydrogen bonds as an imidazolium bridge. The variable temperature magnetic susceptibility for the complex in the temperature range 77-300 K has been interpreted in terms of a single-ion zero-field splitting model with a molecular field term correction. The values obtained for D, g. and zj' are -6.93 cm^?1, 2.00 and -0.90 cm^?1.     

SYNTHESES,CRYSTAL STRUCTURES AND ANTIBACTERIAL ACTIVITIES OF MONONUCLEAR NICKEL(II) COMPLEXES WITH SIMILAR SCHIFF BASES

Journal of Structural Chemistry - Two mononuclear nickel(II) complexes, [Ni(L1)2] (1) and [Ni(L2)2] (2), where L1 and L2 are the anions of 4-methylbenzoic acid (1-pyridin-2-ylmethylidene)hydrazide...     

丙氨酸－N－荒酸镍与稀土多核配合物的合成、表征和抗癌、抑菌活性研究

本文报道了稀土与丙氨酸－Ｎ－荒酸镍［Ｈ２ＮｉＬ２］多核配合物的合成和表征。通过元素分析确定配合物的组成为ＲＥ２（ＮｉＬ２）３·ｘＨ２Ｏ（ＲＥ＝Ｌａ、Ｎｄ、Ｓｍ－Ｅｒ、Ｙｂ；ｘ＝１、４、８），并研究了配合物的摩尔电导、红外光谱和核磁共振氢谱。配合物体外抗癌活性及抑菌活性的测定结果表明，丙氨酸－Ｎ－荒酸镍及其稀土多核配合物均具一定的抗癌、抑菌活性。     

2,2,4,13,13,15,—六甲基—1,5,12,16—四氮杂环二十二烷—N′,N″′—二乙酸及其镧系配合物的合成和表征

本文合成了题头所示大环配体,并制备了它的十四种镧系元素(La～Lu,Pm除外)固体配合物。用元素分析,DTA-TG,红外光谱以及电导测定等手段研究了这些化合物的组成和性质.基于这些分析结果可建议配合物化学式为Ln(H_2L)(NO_3)_3·nH_2O。     

SEPARATION OF IRON AND MANGANESE IN THE EARLY DIAGENETIC PROCESSES AND ITS MECHANISM OF BIOGEOCHEMISTRY

Study shows that the reduction of iron (Fe~(3+)) and manganese (Mn~(4+)) in modern sedi-ments and the diffusive flux of the Mn~(2+) from the pore water into the overlying waterare mainly controlled by bacteria, and the distribution of the bacteria is believed to beaffected strongly by the sedimentary environment. It is the diffusive fluxes between Fe~(2+)and Mn~(2+) that lead to the separation of iron and manganese in the modern sediment at theChangjiang Mouth and near the shore. The level of the separation decreases with theincrease of the overlying water salinity and increases from the surface to the depth. Thismechanism has given a new explanation why manganese is concentrated in sediments onthe oceanic floor of ferromanganese-rich nodules.     

SAPO-5分子筛中硅的取代及其性能研究

本文采用三乙胺为模板剂,用水热法合成不同含硅量的SAPO-5分子筛,并用X射线衍射、扫描电镜、电子探针分析、真空重量吸附等方法对其进行了表征,结果表明硅已进入了骨架,硅同晶非等比取代磷和铝,并且分子筛的孔道是畅通的。 用微型反应器测定了AlPO₄-5及不同量硅取代的SAPO-5分子筛上的异丙苯裂解和邻二甲苯异构化催化反应,结果表明Si引入了催化活性很低的磷酸铝骨架后使其催化活性明显增加,进一步证实了硅是同晶非等比取代磷和铝,因而使分子筛骨架带负电性。 硅进入磷酸铝分子筛骨架的SAPO-5分子筛经红外光谱实验发现不仅具有表面羟基,而且都是酸性羟基。吸附吡啶后的红外光谱结果表明SAPO-5上同时存在B酸和L酸中心,B酸中心数目随着硅含量的增加而增加。