961 resultados para Article 2(4)


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本文研究了二(2,4,4-三甲基戊基)膦酸(Cyanex272)-上胺205-正庚烷乳状液膜分离Sc(Ⅲ)、Fe(Ⅲ)和Lu(Ⅲ)。考察了外相酸度、表面活性剂浓度、流动载体浓度及内相盐酸浓度对Sc(Ⅲ)迁移的影响。并探讨了该液膜体系分离Sc(Ⅲ)、Fe(Ⅲ)和Lu(Ⅲ)的可能性,结果表明,该体系对于稀土矿中Sc(Ⅲ)的分离与分析有良好的应用前景。

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The Mossbauer spectrum of a new organoeuropium complex with a neutral pi-ligand, Eu(eta6-C6Me6) (AlCl4)2, is measured at 88 K. The Mossbauer parameters derived from the spectrum show the divalent nature of the europium ion in this organoeuropium complex. The calculations of the electric field gradient at the Eu nucleus in the crystal indicate that the Eu-Cl bond in the compound may possess a certain covalent character. The low Debye temperature of this complex may be attributed to weak and delocalized pi-bonding between the Eu atom and the benzene ring of hexamethylbenzene, and a slow paramagnetic relaxation is suggested by the Mossbauer effect.

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本文研究了二(2,4,4-三甲基戊基)磷酸(Cyanex 272)的煤油溶液在不同介质(HCI,HNO_3)中对三价混合稀土的萃取分离性能.观测了平衡水相酸度对萃取平衡的影响,由酸度曲线求出相邻元素的平均分离系数,并考察了酸度对反萃取平衡的影响.比较了HCI和HNO_3介质中,Cyanex 272对混合稀土(Ⅲ)的萃取性能.

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研究了二(2,4,4-三甲基戊基)膦酸(BTMPPA,HA)的正辛烷溶液从盐酸介质中萃取钍(Ⅳ)的机理。在未控制离子强度下,萃取平衡反应为:,在控制离子强度为1.0mol/L时,萃取反应为用饱和法确定的萃合物组成为ThCIA_3.计算了萃取反应的平衡常数及热力学函数。研究了饱和萃合物的IR和NMR谱。

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本文报道9种新的含磷杂环化合物的电子轰击质谱(EIMS),并应用B/E、B2/E联动扫描及精确质量测量技术,探讨了该类化合物的质谱断裂机理,发现骨架重排及开环反应是该类化合物主要的质谱特征,而R2基因对重排过程有很大影响。

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LnCl3 (Ln = Nd, Er) reacts with K2C8H8 to yield the complex (C8H8)LnCl.2THF, which reacts with K(2,4-C7H11) (2,4-C7H11 = 2,4-dimethylpentadienyl) to form (C8H8)Ln(2,4-C7H11).THF. The compound (C8H8)Nd(2,4-C7H11).THF(1) crystallizes from the mixed solvent

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The extraction equilibrium data of sulphuric acid and scandium(III) with bis(2,4,4-trimethylpentyl)phosphinic acid (H[BTMPP]) from sulphuric acid solutions have been obtained. There are two extraction mechanisms of scandium(III) with H[BTMPP] at different

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由于在农药方面的广泛应用,新的有机磷化合物不断被合成。质谱是研究其结构的重要手段之一。总结不同类型有机磷化合物的质谱裂解规律将有助于识别未知的有机磷化合物。本文所研究的5—α—[磷酸基]苄基—2—甲基—4—羟基咪唑衍生物是合成的新型除草剂,质谱未见报道。本工作在低分辨EI谱的基础上,根据高分辨精确质量测量和B/E、B_2/E联动扫描亚稳离子测定数据,研究了该类化合物的质谱断裂机理。着重讨论了该类化合物的共同质谱特征,如:P—C,P—N键的断裂;产物离子的开环反应;产物离子的H重排反应和失去CO的反应等。为该类化合物的结构研究提供依据。

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2-乙基己基膦酸单2-乙基己基酯(HEH/EHP)是目前稀土湿法冶金工业中应用最广泛的萃取剂。但存在重稀土离子反萃取酸度高,某些中、重稀土离子对的分离系数小、选择性不高等缺点。所以研究优于HEH/EHP的新萃取体系已引起人们极大的关注。近年来发现,二(2,4,4-三甲基戊基)膦酸(HBTMPP,HL)有可能是萃取稀土元素的有效萃取剂。由于其分子中不含酯氧原子,使得它的pK。值比HEH/EHP高。因此,用HBTMPP萃取稀土及其它高价

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测定了二(2,4,4-三甲基戊基)膦酸(BTMPPA)及其稀土配合物Ln(BTMPP)_3在4000~50cm~(-1)光谱区内的FT-IR光谱和部分配合物的激光拉曼光谱,对其谱带进行了经验归属。发现稀土氧键具有较高的离子键特性。由Ln—O伸缩振动频率值算出其近似力常数约8m dyn/nm。

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合成了除Pm以外的16个稀土与二(2,4,4-三甲基戊基)膦酸(HBTMPP)的固体配合物,其组成为RE(BTMPP)_3,对配合物的性质进行了表征,热分析表明,在氩气中,热分解是一步完成的,在空气中,热分解分二步完成,前者的热分解产物是RE_4 (P_2O_7)_3,后者的产物为RE_2P_4O_(13)测定了配合物的振动光谱,对其主要吸收谱带进行了归属,配合物中RE-O键具有较高的离子特性

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The half-open vanadocene, V[2,4-(CH3)2C5H5](C5H5)CO, was obtained by the reaction of V[2,4-(CH3)2C5H5](C5H5)PMe3 with CO in petroleum ether at room temperature. Its crystal structure was determined by X-ray diffraction technique. The crystal was monoclinic with space group P2(1)/n, a = 16.614(3), b = 7.636(1), c = 19.128(6) angstrom, beta = 99.92(2)-degrees, V = 2390.5(9) angstrom3, and Z = 8. The final R value was 0.043. The V(1)-CPD(1) (half) (PD = 2,4-(CH3)2C5H5) bonds were shorter (0.038 angstrom) than the V(1)-CCP(1) (half) (CP = C5H5) bonds, averaging 2.224(4) versus 2.262(4) angstrom, respectively. 4V[2,4-(CH3)2C5H5](C5H5)CO has been characterized by IR and EPR methods.

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The reaction of EuCl3, AlCl3 and C6Me6 in toluene gives the Eu(II) complex [Eu(eta-6-C6Me6)(AlCl4)2]4; X-ray crystal determination shows the molecule to be a cyclotetramer, in which the four Eu(C6Me6)AlCl4 units are connected via four groups of eta-2-AlCl4.

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本文研究了二(2,4,4-三甲基戊基)膦酸(HBTMPP)的正辛烷溶液对Sc(Ⅲ),Fe(Ⅱ)的萃取平衡影响,研究了酸度对Sc(Ⅲ)、Fe(Ⅲ)分配比影响,探讨了Sc(Ⅲ)和Fe(Ⅲ)的分离可能性。用斜率法确定了萃合物组成和萃取反应机理,并研究了萃合物的IR、NMR谱,求得了萃取反应的平衡常数和热力学函数。

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LB膜的特性在很大程度上决定于成膜分子的结构。铜酞菁衍生物具有大π键电子共轭体系,有明显的光电特性,成膜性好,很适于作LB膜气敏材料。我们在前期工作的基础上,为探明气敏特性与化合物结构间的关系,设计并合成了标题化合物,并对其LB膜的气敏特性进行了研究。