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在无水乙醇中,使低水合氯化稀土(RE=La, Pr, Nd, Sm)与吡咯烷二硫代氨基甲酸铵(APDC)和1,10-邻二氮菲(σ-phen·H2O)反应,制得其三元固态配合物.用化学分析和元素分析确定它们的组成为RE (C5H8NS2)3(C12H8N2) (RE= La, Pr, Nd, Sm).IR光谱说明RE3+分别与3个PDC-的6个硫原子双齿配位,同时与σ-phen的2个氮原子双齿配位,配位数为8.用精密转动弹热量计测定了它们的恒容燃烧热ΔcU,分别为-17776.94±7.72, -17810.41±7.93, -17762.71±7.91和-17482.42±9.35 kJ·mol-1;并计算了它们的标准摩尔燃烧焓和标准摩尔生成焓,分别为-17792.43±7.72, -17825.90±7.93, -17778.20±7.91, -17497.91±9.35 kJ*mol-1和-83.05±8.60, -64.70±9.40, -104.77±8.78, -388.70±10.13 kJ·mol-1.估算出未研究的同类配合物Ce(C5H8NS2)3(C12H8N2)和Pm(C5H8NS2)3(C12H8N2)的和分别为-17815, -17660 kJ·mol-1和-60, -217 kJ·mol-1. 相似文献
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Treatment of hydrate rare-earth(RE=La,Pr,Nd,Sm-Lu)chloride with ammonium pyrrolidinyldithiocarboxy-late(apdtc)and 1,10-phenanthroline(phen)gave rise to thirteen complexes with an empirical formulaRE[(pdtc)_3(phen)].The enthalpies of solution of hydrate rare-earth(RE= Sm-Ho,Tm-Lu)chloride,apdtc and phenin ethanol were measured by an RD-496 Ⅲ microcalorimeter at 298.15 K,along with the mixing enthalpy of etha-nol solution of APDC and that of phen and the enthalpies of reaction of formation of the title complexes in ethanol.The enthalpies of reaction of formation of the title complexes in solid were available through a rationally thermo-chemical cycle.Using an RD-496 Ⅲ microcalorimeter,a model was developed for calculating the specific heat ca-pacity and the responding specific heat capacity of the complexes were determined.The thermochemical properties,including the enthalpies of solution of hydrate rare earth chloride in ethanol,the enthalpies of reaction of formationof the title complexes in ethanol,the enthalpies of reaction of formation of the title complexes in solid,the specialheat capacities at room temperature,the standard molar enthalpies of combustion and the standard molar enthalpiesof formation for this series of complexes versus the atomic numbers of rare earth,presented triplet effect,which isrepresentative of certain covalent bond between RE and the ligands and the result of 4f electron not shielded fullyby 5s5p. 相似文献
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1初中课程中的螺线管磁场及其演示实验
1979年人民教育出版社出版了文革以后的第一套全国统编教材,书中安排了如图1所示的演示实验.书中的文字说明是:“如图5—27(图5—27是教科书插图编号——笔者)所示,给螺线管通电,铁块受到螺线管的吸引使弹簧伸长.调节变阻器,改变通过螺线管的电流强度,可以看到电流越强,弹簧被拉伸得越长.这表明通过螺线管的电流越强它的磁性也越强.如果换用匝数不同的螺线管而保持通过螺线管的电流强度跟前面的实验一样, 相似文献
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以5-硝基间苯二甲酸与硝酸钬在水溶液中反应制备了配合物Ho2(5-nip)2-(5-Hnip)2(H2O)8·4H2O(5-H2nip为5-硝基间苯二甲酸),并对其进行了元素分析、红外、热重和X-射线单晶衍射表征.结构分析表明,配合物中5-Hnip?以?2-?1:?1双齿桥连模式将两个相邻Ho3+离子连接成二聚体形式,分子间的O–H···O氢键和三种不同的?-?堆积作用使相邻的二聚体单元与游离水分子形成三维超分子结构.运用RD496-2000型微热量计在298.15 K下测定了该化合物在水溶液中生成反应的焓变.设计合理的热化学循环,辅助文献的热化学数据,以Hess定律计算得到了该化合物在298.15 K下的标准摩尔生成焓θf m?H为?(3371.5±16.9)kJ/mol. 相似文献
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