伯胺N_(1923)从硫酸溶液中萃取稀土元素(Ⅲ)、铁(Ⅲ)和钍(Ⅳ)的机理

本文研究了伯胺N_(1923)萃取H_2SO_4、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的平衡规律。通过分配法、饱和法等的研究及IR测定,提出了不同酸度下H_2SO_4、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的萃取机理。观测了稀土元素(Ⅲ)的萃取率与原子序数的递变规律及钇的位置。     

三种中性磷萃取剂萃取分离铀(Ⅵ)与钍(Ⅳ)的研究

以磺化煤油作稀释剂,比较研究了三种中性磷萃取剂甲基膦酸二甲庚酯(P350)、磷酸三异戊酯(TiAP)和磷酸三丁酯(TBP)在HNO3溶液中对U(Ⅵ)、Th(Ⅳ)及自身对HNO_3的萃取行为。分别考察了两相接触时间、酸度、萃取剂浓度和温度对U(Ⅵ)、Th(Ⅳ)萃取分配比的影响。结果表明它们萃取HNO_3均形成1∶1型萃合物。随HNO_3浓度增加,U(Ⅵ)和Th(Ⅳ)的萃取分配比先增大后减小。相同条件下,P350对U(Ⅵ)、Th(Ⅳ)的萃取能力及铀/钍分离选择性显著大于TiAP和TBP。当被萃水相存在大量Th(Ⅳ)时,Th(Ⅳ)对U(Ⅵ)的萃取有盐析作用,U(Ⅵ)的分配比增加;Th(Ⅳ)的分配比下降。斜率分析表明三种萃取剂与U(Ⅵ)和Th(Ⅳ)分别形成2∶1和3∶1型萃合物。同时,给出了表观萃取平衡常数Kex和萃取反应热力学函数ΔH、ΔS和ΔG的值。用ICP-AES分析方法,还对三种萃取剂在不同浓度的HNO_3溶液中的溶解度进行了测定。此外,还测定了三者萃取Th(Ⅳ)的极限有机相浓度(LOC)。     

KBr-乙醇-(NH_4)_2SO_4体系析相萃取分离和富集铱的研究

研究了KBr-乙醇-(NH_4)_2SO_4水体系析相萃取分离和富集铱的行为及与一些金属离子分离的条件.结果表明,(NH_4)_2SO_4能使乙醇的水溶液分成两相,在分相过程中,Ir(Ⅳ)与KBr生成的IrBr_6~(2-)与质子化乙醇(C_2H_5OH~(2+))形成的缔合物[IrBr_6~(2-)][C_2H_5OH~(2+)]_2能被乙醇相完全萃取.当乙醇、KBr和(NH_4)_2SO_4分别为体积分数30%、4.0×10~(-3)mol/J L、0.3 g,mL.pH 3时,Ir(Ⅳ)的萃取率达到99.5%以上,Ga(Ⅲ),Al(Ⅲ),Cr(Ⅲ),Mo(Ⅵ),Fe(Ⅲ),Ni(Ⅱ),Zn(Ⅱ),Co(Ⅱ),Mn(Ⅱ),V(Ⅴ),Ag(Ⅰ),Ru(Ⅲ)和Rh(Ⅲ)基本不被萃取,实现了Ir(Ⅳ)与上述金属离子的分离.     

伯胺N1923从硫酸溶液中萃取稀土元素(Ⅲ)、铁(Ⅲ)和钍(Ⅳ)的机理

本文研究了伯胺N₁₉₂₃萃取H₂SO₄、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的平衡规律。通过分配法、饱和法等的研究及IR测定,提出了不同酸度下H₂SO₄、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的萃取机理。观测了稀土元素(Ⅲ)的萃取率与原子序数的递变规律及钇的位置。     

硫酸铵-溴化钾-乙醇体系萃取分离金

研究了(NH4)2SO4存在下,KBr-乙醇体系萃取分离Au(Ⅲ）的行为。实验表明,Br^-与Au(Ⅲ）形成的AuBr4^-很容易被萃取到乙醇相中。当溶液中KBr、(NH4)2SO4和无水乙醇浓度分别为0．04g／mL、0．30g／mL、30％(V／V),pH=2—4时能使Au(Ⅲ）的萃取率达到100％,Al（Ⅲ）、Ni(Ⅱ)、Mn(Ⅱ)、Cr（Ⅲ）、Co(Ⅱ)、Fe（Ⅲ）、Zn(Ⅱ)、Cu(Ⅱ)、Mo（Ⅵ)、U(Ⅳ)基本不被萃取,实现了Au（Ⅲ）与上述离子的分离。     

血吸虫病化学治疗的研究 Ⅴ——2-氨基葡萄糖与巯基脂酸形成的酰胺

O-四乙酰基-2-氨基-2-脱羟-D-葡萄吡喃糖与相应的溴代脂酰氯作用,生成溴乙酰胺(Ⅱa),β-溴丙酰胺(Ⅳa),α,β-二溴丙酰胺(Ⅴa)及α,α′-二溴己二酰胺(Ⅵa)。这些溴代酰胺以及相应已知的α-溴丙酰胺(Ⅲa)与乙硫羟酸钾的置换作用生成相应的乙酰巯基脂酰胺。巯基及羟基上的乙酰基用甲醇钠水解后制成2-氨基葡萄糖的四种巯基脂酰胺(Ⅱc,Ⅲc,Ⅳc,Ⅵc)。     

双-(4-二甲胺苯基)-安替比林甲醇-Triton X-100分光光度测定铋

最后酸度为0.11—0.14mol/L的H_2SO_4介质中,在一定量Triton X-100存在下,双-(4-二甲胺苯基)-安替比林甲醇可与BiI_4~-生成组成比为Bi∶R=1∶2的三元络合物,其λ_(max)=650nm。铋量在0—100μg/25mL范围内遵守比尔定律,ε_(650)为1.27×10~4,100mg Fe(Ⅱ)和Al(Ⅲ),5mg Fe(Ⅲ),150μg Cr(Ⅲ),108μg Ca(Ⅱ),100μg Co(Ⅱ),50μg Se(Ⅳ),7μg Pb(Ⅱ),6μg Sn(Ⅳ)、W(Ⅵ)、Ni(Ⅱ)和Zn(Ⅱ),5μg Hg(Ⅱ)、V(Ⅴ)和Cr(Ⅵ),4.5μg Mo(Ⅵ),2μg Sb(Ⅲ)和Cd(Ⅱ)不干扰测定。本法用于纯铁中微量铋(0.04—0.08％)及纯铝人工合成液中铋(0.04—0.1％)的测定,效果较好。标准加料试验的回收率为90—107％,操作简便、快速。     

硫酸铵-3，5-二溴水杨基荧光酮-乙醇体系萃取分离钼

在含有一定浓度硫酸铵的条件下,乙醇水溶液能形成盐水与乙醇液-液两相,研究了Mo(Ⅵ)与3,5二溴水杨基荧光酮(DBSAF)形成的配合物在乙醇盐水萃取体系液-液两相中的分配行为.试验表明,在PH 1～6范围内,硫酸铵浓度为350 g·L-1,试液中乙醇与水的体积比为3比7,1×10-4mol·L-1 DBSAF溶液加入量为2 mL及试液总体积为10 mL的条件下,Mo(Ⅵ)均保持很高的萃取率,用控制酸度的方法实现了Mo(Ⅵ)与常见过渡元素离子Co(Ⅱ)、Zn(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Mn(Ⅱ)、Fe(Ⅲ)、W(Ⅵ)的定量分离,试验了钼(Ⅵ)与上述各共存离子的分离,钼(Ⅵ)的萃取率均大于97%,而其他共存离子的萃取率均小于5%.     

皱叶香茶菜化学成分的研究

从采自西藏的皱叶香茶菜中分离鉴定了3对B-闭联对映贝壳杉烯型二萜化合物:二萜化合物皱叶香茶菜素(Ⅰ)和二氢皱叶香茶菜素(Ⅱ);isodocarpin(Ⅲ)和dihydroisodocarpin(Ⅳ)及Carpalasionin(Ⅴ)和dihydrocarpalasionin(Ⅵ)。(Ⅰ)、(Ⅲ)和(Ⅴ)分别与对应的二氢化合物(Ⅱ)、(Ⅳ)和(Ⅵ)以混合物的形式被分离和鉴定。化合物(Ⅱ)为新化合物,(Ⅰ)、(Ⅳ)和(Ⅵ)首次在自然界发现,(Ⅲ)和(Ⅴ)为已知化合物。     

新试剂对甲基二溴偶氮胂与钍显色反应的研究和应用

近年来几种新的钍显色剂相继应用,使分光光度法测钍取得了显著的进展。本文研究了新试剂对甲基二溴偶氮胂与钍反应的分光光度性能。在1.2N盐酸溶液中,试剂与钍形成灵敏度高且十分稳定的有色配合物,其摩尔吸光系数为1.34×10~5L·mol~(-1)·Cm~(-1)。试液中共存Ca(Ⅱ)7mg,Mg(Ⅱ)20mg,Al(Ⅲ)20~*mg,Fe(Ⅲ)15~*mg,Bi(Ⅲ)17mg, Mn(Ⅱ )15~*mg,Cu(Ⅱ)15mg,Ni(Ⅱ)10~*mg,Co(Ⅱ)20~*mg,Pb(Ⅱ)2mg,Cd(Ⅱ)10~*mg,SC(Ⅲ)4mg,RE0.004mg,Ti(Ⅵ)1.8mg,Zr(Ⅳ)0.04mg,Si(Ⅵ)16~*mg,V(Ⅴ)1.0mg,Sn(Ⅳ)10~*mg,U(Ⅳ)1.5~*mg,Cr(Ⅵ)1.5mg,Mo(Ⅵ)20mg,WO_4~(2-)6.0mg,PO_4~(3-)200~*mg,H_2C_2O_4 500~*mg,酒石酸500~*mg,柠檬酸400mg,NH_4F10mg(~*表示未做到最大限量)不干扰钍的测     

The crystal structure of LaIr4B4, ThOs4B4, ThIr4B4 (NdCo4B4-type) and URu4B4, UOs4B4 (LuRu4B4-type)

The crystal structure of LaIr₄B₄ has been refined from single crystal counter data. LaIr₄B₄ is tetragonal,P4₂/n,Z=2, isotypic with NdCo₄B₄, |F|/|F _o|=0.039 for 312 independent reflections [|F _o|>2 (F _o)]. ThIr₄B₄ and ThOs₄B₄ also belong to the NdCo₄B₄-type structure. URu₄B₄ and UOs₄B₄ were found to crystallize with LuRu₄B₄-type structure. The crystal chemistry of (RE)T ₄B₄-phases is discussed and simple geometric relations are shown to exist between them.Dedicated to Prof.B. T. Matthias in celebration of his 60th birthday.     

Schwingungsspektren von As4S4 und As4Se4

Vibrational Spectra of As₄S₄ and As₄Se₄ The vibrational spectra of solid α- and β-As₄S₄ and the Raman spectrum of molten As₄S₄ have been recorded. The assignments of the frequencies are proposed mainly based on polarization data. The Raman melt spectra suggest that As₄S₄ molecules (symmetry D_2d) are retained in the molten state. A partial decomposition of the melt by prolonged laser irradiation was observed. The Raman spectrum of solid As₄Se₄ is presented and the frequencies are tentatively assigned to an As₄Se₄ molecule of the cradle type, possessing D_2d symmetry.     

Electronic structures of the boron cage molecules B4H4, B4Cl4 and B4F4

Ab initio calculations have been performed on B₄H₄, B₄Cl₄ and B₄F₄ in order to aid our understanding of the bonding in these compounds, which is presumably based on a tetrahedral boron cage. This cage has only 8 electrons and so is less than that expected on the basis of the usual framework electron counting rules. Basis sets with polarisation functions were used at the SCF, CI and CPF levels of theory to confirm that the T _d structures are indeed more stable than the D _4h ones. Davidson-Roby population analyses were able to show that many factors, including 3-centre 2-electron bonding and backbonding from the ligand to the boron cage, are of importance in determining the relative stability of the three compounds, of which B₄Cl₄ is the only one that has yet been observed experimentally.     

Zintlphasen mit isolierten SiAs4- bzw. GeAs4-Anionen: Darstellung und Struktur von Ba4SiAs4 und Ba4GeAs4 sowie Sr4SiAs4 und Sr4GeAs4

Die erstmals dargestellten isotypen Verbindungen Ba₄SiAs₄, Ba₄GeAs₄, Sr₄SiAs₄ und Sr₄GeAs₄ kristallisieren kubisch, Raumgruppe P4 3n, mit 8 Formeleinheiten in der Elementarzelle: In den Strukturen liegen isolierte, d.h. nur von Ba-Ionen umgebene SiAs - bzw. GeAs -Tetraeder vor. Die Verbindungen sind die bisher eindrucksvollsten Beispiele für Zintlphasen mit komplexen Anionen. Zintl Phases with Isolated SiAs₄ or GeAs₄ Anions: Preparation and Structure of Ba₄SiAs₄, Ba₄GeAs₄, Sr₄SiAs₄, and Sr₄GeAs₄ The new compounds Ba₄SiAs₄, Ba₄GeAs₄, Sr₄SiAs₄, and Sr₄GeAs₄ have been prepared and their structures determined. They crystallize in the cubic system, P4 3n, with axes: data see “Inhaltsübersicht”. There are isolated SiAs or GeAs tetrahedra in the structures. The compounds can be interpreted as Zintl phases with complex anions.     

Zur Kenntnis von K4PbO4 und Rb4PbO4

On K₄PbO₄ and Rb₄PbO₄ For the first time single crystals of K₄[PbO₄] have been prepared by heating K₄PbO₃ in O₂. The structure has been refined [K₄[PbO₄]: 3029 I₀(hkl), four circle diffractometer PW 1100, ω-scan, MoKα, R = 6.73%, R_w = 6.64%, P1 ; a = 658.62(15), b = 658.41(12), c = 986.64(21) pm, α = 79.74(2)°, β = 108.45(2)°, γ = 112.49(2)°, d_x = 3.79 g · cm^?3, d_pyk = 3.78 g · cm^?3, Z = 2; Rb₄[PbO₄]: a = 686.94(18), b = 684.43(18), c = 1020.73(21) pm, α = 79.28(2)°, β = 108.40(2)°, γ = 113.02(2)°, d_x = 4.87 g · cm^?3, d_pyk = 4.85 g · cm^?3, Z = 2, (from Rb₂PbO₃ and Rb₂O)]. Both compounds are isotypic with K₄SnO₄. The Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.