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1.
A solid ternary mixture consisting of NaF,silicon and one metal oxide such as La2O3,CeO2,Pr6O11,Nd2O3,and Y2O3 was prepared and usedas de-fluorinated reagent for CF4 decomposition.The results show that 90% conversion of CF4 can be reached initially over NaF-Si-La2O3,NaF-Si-CeO2,NaF-Si-Nd2O3,and NaF-Si-Y2O3 at 850 C.The fresh and used reagents were characterized using XRD and XPS techniques.It was found that the active components of NaF and metal oxides in NaF-Si-CeO2,NaF-Si-Pr6O11,NaF-Si-Nd2O3,and NaF-Si-Y2O3 weretransformed into inert phases of mixed metal fluorides and silicates,respectively,resulting in an ineffective utilization of these de-fluorinatedreagents,whereas no inert phases from NaF and La2O3 can be observed in the used NaF-Si-La2O3,indicating the NaF-Si-La2O3 reagent couldbe utilized more efficiently than the other reagents in CF4 decomposition.  相似文献   

2.
运用量子化学密度泛函理论UB3LYP/6-311+G*和高级电子相关校正的偶合簇(CCSD(T)/6-311+G*)方法,对CH3CH2,CH3CHCl和CH3CCl2自由基与NO2反应的机理和动力学进行了理论研究,得到了体系的势能面信息和可能的反应机理.根据计算得到的各反应热力学参数及反应能垒,采用传统过渡态理论计算了各反应在温度T=298 K和T=700 K时的速率常数.研究结果表明,该类反应均通过1个中间体和1个过渡态生成产物,产物分别为CH3CHO+HNO,CH3CHO+ClNO和CH3CClO+ClNO.  相似文献   

3.
张霞  黄雪莉 《化学通报》2015,78(4):337-341
采用等温溶解平衡法研究了四元体系Na+//Cl-,SO42-,NO-3-H2O在5、0、-5与-15℃下的相平衡关系。结果表明,4个温度下体系无复盐形成,平衡相图的构型基本一致;平衡相图均由3个结晶区(Na2SO4·10H2O、Na Cl和Na NO3)、3条单变量曲线(Na Cl-Na2SO4·10H2O、Na Cl-Na NO3、Na NO3-Na2SO4·10H2O)及1个共饱点(Na Cl-Na NO3-Na2SO4·10H2O)组成;4个温度下的平衡相图相比,随着温度的下降Na2SO4·10H2O结晶区不断扩大,Na Cl和Na NO3结晶区相对缩小;与该体系常温下的平衡相图相比,由于无复盐形成,低温下的相图大为简化。  相似文献   

4.
Reaction of tin tetrachloride with the appropriate Grignard reagent gave Sn[C6H4-CH(OCH2)2]4 (2), which was transformed to Sn[C6H4-CHO]4 (3) and its hydrazido and amino derivatives Sn[C6H4-CHN-NH-C6H3-2,4-(NO2)2]4 (5) and Sn{C6H4-CH[N(C2H4)2O]2}4 (8). Oxidation of (3) produced Sn[C6H4-COOH]4 (4) while reduction of (3) gave Sn[C6H4-CH2-OH]4 (6). From the acid 4, an amino acid Sn[C6H4-CO-NH-CH2-CO-OCH3]4 (7) could be obtained by reaction with the methyl ester of glycine. All compounds were isolated in pure form with yields of 40-64% and were characterised by spectroscopic means (heteronuclear NMR) or by X-ray structure determination (3).  相似文献   

5.
6.
研究了AlCl3(ZnCl2、MgCl2)对Sm2O3的氯化效果以及Sm2O3在LiCl-KCl-AlCl3(ZnCl2、MgCl2)熔盐体系中的电化学行为。在LiCl-KCl-Sm2O3熔盐中加入AlCl3(ZnCl2、MgCl2)后,ICP测量结果表明,AlCl3体系中Sm(Ⅲ)离子的浓度最高,并且在923 K时达到最大值;固相反应表明,AlCl3氯化Sm2O3生成SmCl3,而Sm2O3和ZnCl2(MgCl2)反应生成SmOCl。电化学行为表明,AlCl3体系中观察到了两种Al-Sm的合金峰,而ZnCl2体系中只观察到Zn-Sm金属间化合物的形成峰,MgCl2体系中没有形成合金。在-6.25 A·cm-2下,W电极上恒电流电解2 h获得了Al-Li-Sm合金,经XRD分析,合金为Al2Sm相。  相似文献   

7.
研究了AlCl_3(ZnCl_2、MgCl_2)对Sm_2O_3的氯化效果以及Sm_2O_3在Li Cl-KCl-AlCl_3(ZnCl_2、MgCl_2)熔盐体系中的电化学行为。在Li Cl-KCl-Sm_2O_3熔盐中加入AlCl_3(ZnCl_2、MgCl_2)后,ICP测量结果表明,AlCl_3体系中Sm(Ⅲ)离子的浓度最高,并且在923 K时达到最大值;固相反应表明,AlCl_3氯化Sm_2O_3生成SmCl_3,而Sm_2O_3和ZnCl_2(MgCl_2)反应生成Sm OCl。电化学行为表明,AlCl_3体系中观察到了两种Al-Sm的合金峰,而ZnCl_2体系中只观察到Zn-Sm金属间化合物的形成峰,MgCl_2体系中没有形成合金。在-6.25 A·cm~(-2)下,W电极上恒电流电解2 h获得了Al-Li-Sm合金,经XRD分析,合金为Al_2Sm相。  相似文献   

8.
The Michael addition of nitromethane to 3-buten-2-one has been carried out in the absence of solvent, using potassium fluoride supported on Al2O3, ZnO, SnO2, sepiolite, AlPO4, AlPO4–Al2O3 and AlPO4–ZnO catalysts. We found that KF/ZnO easily performed the Michael addition and thus, ZnO is a better support for the basic reagent than Al2O3. Besides, the Michael addition was not successful with AlPO4 or AlPO4-metal oxide acidic supports.
3--2- , , Al2O3, ZnO, SnO2, , AlPO4, AlPO4–Al2O3 AlPO4–ZnO. , KF/ZnO .. ZnO, , , Al2O3. , , AlPO4 AlPO4- .
  相似文献   

9.
The kinetics of the peroxy radicals RHFO2 reactions with NO has been studied by using pulse radiolysis and UV absorption spectroscopy. The rate constants of interaction of oxygen atoms with NO − k 2 = 2.2±0.2·10−12 cm3·s−1 and NO2k 3 = 2.1±0.2·10−11 cm3·s−1 were found in agreement with the literature values. The bath gases (SF6 or CO2) have got minor effect on the rate constants of RHFO2+NO→NO2+prod. reactions; RHFO2 = CH3CH2O2, CH3CHFO2, CH3CF2O2, CF3CH2O2, CF3CHFO2. The obtained rate coefficients are in the scope of the literature values, although they are lower than those recommended in NIST database. The reasons are discussed.  相似文献   

10.
Single crystals of Cs4[(UO2)2(C2O4)(SO4)2(NCS)2] · 4H2O (I) and (NH4)4[(UO2)2(C2O4)(SO4)2(NCS)2] · 6H2O (II) have been synthesized and studied by X-ray diffraction. The crystals of both compounds are orthorhombic with the space group Pbam, Z = 2, and unit cell parameters a = 12.0177(3) ?, b = 18.6182(5) ?, c = 6.7573(10) ?, R = 0.0376 (I); a = 11.6539(9) ?, b = 18.3791(13) ?, c = 6.7216(5) ?, R = 0.0179 (II). The main structural units of crystals I and II are [(UO2)2(C2O4)(SO4)2(NCS)2]4− chains belonging to the crystal-chemical group A2K02B22M21 (A = UO22+, K02 = C2O42−, B2 = SO42−, M1 = NCS) of the uranyl complexes. The uranium-containing chains are joined into a three-dimensional framework due to a system of electrostatic interactions with the cesium or ammonium ions in the structure of I. In the structure of II, this framework is additionally stabilized by hydrogen bonds involving the outer-sphere water molecules and ammonium ions. Original Russian Text ? I.V. Medrish, A.V. Virovets, E.V. Peresypkina, L.B. Serezhkina, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 7, pp. 1115–1120.  相似文献   

11.
Treatment of Os(κ2-S2CNMe2)H(CO)(PPh3)2 with HSiMeCl2 or HSiCl3 gives in high yield Os(κ2-S2CNMe2)(SiMeCl2)(CO)(PPh3)2 (1) or Os(κ2-S2CNMe2)(SiCl3)(CO)(PPh3)2 (2), respectively. The crystal structures of both compounds have been determined and the Os-Si distances are 2.3672(10) Å for 1 and 2.3449(12) Å for 2. In solution, and under forcing conditions, both compounds are extraordinarily unreactive towards hydroxide ions.  相似文献   

12.
The novel 3D coordination polymer {Cd2(C4H2O4)2(C4H6N2)2(H2O)2 · 2H2O} n (I) has been synthesized and characterized by standard solid state methods including single-crystal X-ray crystallography. The compound crystallizes in triclinic space group P [`1]\bar 1 with a = 8.589(4), b = 10.585(3), c = 13.094(1) ?, α = 84.91(4)°, β = 79.21(0)°, γ = 83.76(4)°, V = 1159.5(1) ?3, Z = 2. The fumaric acid acts as a multimodal bridging ligand in the polymer unit. One of the fumaric acid ligands tridentately chelates to two Cd2+ cations in the same dinuclear unit, while the other bidentately chelates to two Cd2+ cations in another dinuclear unit. The two metal centers possess slightly distorted pentagonal bipyramid geometry with four Cd {(μ4-fumarato)-(μ2-fumarato)-bis(2-methylimidazolyl)-diaqua} units joining together to form a 28-membered ring. The whole molecule exhibits a through channel along y-axis and 2D layers in xz plane. With hydrogen bond and π-π interaction, the 2D layers construct a 3D microporous network.  相似文献   

13.
 Oxo peroxo glycolato complexes of vanadium(V) (M 2[V2O2(O2)2(C2H2O3)2nH2O (n=0, 1; M=NBu4 + (1), K+ (2), NH4 + (3), Cs+ (4), NPr4 + (5)) as well as (NBu4)2[V2O4(C2H2O3)2]ċ H2O (6) have been prepared and characterized by spectroscopic methods. X-Ray structure analysis of 1 revealed the presence of dinuclear [V2O2(O2)2(C2H2O3)2]2− anions with a (chemical structure) bridging core and six coordinated vanadium(V) atoms in a distorted pentagonal pyramidal array.  相似文献   

14.
廖玲  黄雪莉 《化学通报》2016,79(1):62-65,61
新疆盐湖资源丰富,冬季寒冷漫长,已有研究表明利用冬季冷能可以实现卤水浓淡分离。本文采用等温溶解平衡法针对新疆含硝酸盐卤水开发过程中涉及的Na~+,K~+//Cl~-,SO_4~(2-),NO_3~-H_2O及Na~+,K~+//Cl~-,NO_3~-H_2O体系273.15K下的相平衡关系进行了研究。通过查找文献及实验获得两个体系各盐的溶解度及溶液密度,并绘制相图。研究表明,上述四元体系的干盐相图有2个零变量点、5条单变量溶解度曲线、4个单盐结晶区分别对应于NaNO_3、NaCl、KNO_3和KCl,与该体系在298.15K下的相图相比,硝酸钾结晶区扩大很多;上述五元体系干盐相图(NaCl饱和)有2个零变量点、5条单变量溶解度曲线、4个两盐结晶区分别对应于NaCl+NaNO_3,NaCl+Na_2SO_4·10H_2O,NaCl+KNO_3,NaCl+KCl,与该体系298.15K下的相图相比,复盐钾芒硝和钠硝矾结晶区消失,芒硝结晶区扩大,相图大为简化。  相似文献   

15.
A novel binuclear praseodymium(III) complex with N-(2-propionyl)salicyloylhydrazone (C10H10N2O4, H3L) and p-hydroxybenzoic acid (C7H6O3, Phba) was prepared in a H2O-C2H5OH mixed solution, and the crystal structure of [Pr2(H2L)2(Phba)4(H2O)2] · 2H2O (I) was determined by X-ray single crystal diffractometry. Complex I crystallizes in the monoclinic system, space group P21/c, a = 1.1050(4), b = 1.9534(7), c = 1.2376(4) ?, β = 94.955(7)°, and Z = 4. In the structure each Pr3+ ion lies in a single capped square antiprism geometry coordinated by carboxyl O and acyl O atoms and azomethine N atom of one ligand (H2L form), which coordinates via the keto form, four carboxyl O atoms from two Phba, and O atoms of two water molecules. In each molecule, two tridentate ligands were coordinated by the H2L form, and each Pr3+ ion was chelated by the carboxyl group from Phba. The carboxyl groups of H2L and other two Phba were coordinated via μ2-bridging form and bidentate bridging form, respectively. Complex I and ligands Phba and H3L were also searched for biological activity against Valsa mali by the growth rate method. The result showed that the inhibitory rate of ligands Phba and H3L is better than complex I, especially Phba.  相似文献   

16.
CO2     
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17.
The vanadium(V) complexes K[VO2(SeO4)(H2O)] and K[VO2(SeO4)(H2O)2] · H2O were synthesized using original procedures; their physicochemical properties were studied, and the crystal structure was determined on the basis of X-ray diffraction and neutron diffraction data. The structure of K[VO2(SeO4)(H2O)2] · H2O is composed of VO6 octahedra connected to form infinite chains by bridging SeO4 tetrahedra. Each VO6 tetrahedron has short terminal V-O bonds forming the bent dioxovanadium group VO2+ The unit cell parameters of K[VO2(SeO4)(H2O)2] · H2O are a = 6.4045(1) ?, b = 9.9721(2) ?, c = 6.6104(1) ?, β = 107.183(1)°, V = 403.34 ?3, Z = 2, monoclinic system, space group P21. The complex K[VO2(SeO4)(H2O)] forms a two-dimensional layered structure composed of highly distorted VO6 octahedra having two short terminal V-O bonds and SeO4 groups coordinated simultaneously by three vanadium atoms. This compound crystallizes in the monoclinic system (space group P21/c): a = 7.3783(1) ?, b = 10.5550(2) ?, c = 10.3460(2) ?, β = 131.625(1)°, V = 602.894(5) ?3, Z= 4. The vibrational spectra of the studied compounds are fully consistent with their structural features.  相似文献   

18.
Quantitative IR investigation of solid-state [Co(NH3)5ONO]XY[Co(NH3)5NO2]XY (XY=Cl2, Br2, I2, (NO3)2 Cl; NO3) linkage isomerization in KBr pellets has shown the kinetics to depend upon the outer-sphere anion. The red shift of the 5(ONO) band during isomerization is a linear function of transformation degree.  相似文献   

19.
20.
采用管式炉和荷电低压撞击器(electrical low pressure-impactor,ELPI)研究了徐州烟煤在O2/CO2条件下燃烧后生成的PM2.5排放特性。结果表明,在O2/CO2气氛下,煤粉在不同O2浓度燃烧所产生的PM2.5质量浓度均呈双峰分布,峰值分别在0.1和2.0 mm左右;随着氧含量的增加,PM2.5的质量浓度增加;S、K和Na在亚微米颗粒上明显富集,而Si和Ca未在亚微米颗粒上富集;通过对颗粒物的粒径分布、元素分析和形貌观察,认为亚微米颗粒主要是矿物质蒸发鄄凝结机制形成的,而超微米颗粒主要是煤焦与外部矿物质的破碎以及内在矿物质聚合形成的。  相似文献   

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