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1.
以3-叠氮-1,2,4-三唑为配体,PA–(苦味酸根)或HTNR–(2,4,6-三硝基间苯二酚脱去一个羟基的质子后形成的离子)为外阴离子,制备得到了两种新的配合物:[Zn(AZT)4(H2O)2](PA)2∙4H2O和[Zn(AZT)2(H2O)4](HTNR)2∙4H2O。[Zn(AZT)4(H2O)2](PA)2∙ 4H2O的X射线晶体数据表明,中心Zn2+离子与来自4个AZT分子的N原子和2个H2O分子的O原子配位;而对于[Zn(AZT)2(H2O)4](HTNR)2∙4H2O来说,6个配位原子来自2个AZT分子的N原子和4个H2O分子的O原子。在两种配合物中,AZT配体分子的配位点都是三唑环上的4位N原子。H2O分子对于分子间氢键的形成起到了重要的作用,在分子间氢键的作用下形成了配合物的晶体结构。在[Zn(AZT)4(H2O)2](PA)2∙4H2O的晶体结构中,还存在错位面对面π-π堆积作用,它对于晶体结构的形成和稳定性也起到了重要作用。TG-DTG和DSC分析结果显示,[Zn(AZT)2(H2O)4](HTNR)2∙4H2O的热分解过程不如[Zn(AZT)4(H2O)2](PA)2∙4H2O剧烈,原因在于前者分子中含有较多配位水分子和较少AZT配体分子。感度测试结果表明,[Zn(AZT)4(H2O)2](PA)2∙4H2O有一定的火焰感度,而[Zn(AZT)2(H2O)4](HTNR)2∙4H2O却对热不敏感;两种化合物在撞击和摩擦作用下都表现钝感。  相似文献   

2.
以1,5-二氨基四唑(DAT)为配体,苦味酸根(PA)为外阴离子制备得到了一种新的配合物[Co(DAT)6](PA)2∙4H2O,并通过X射线单晶衍射分析、元素分析和FT-IR分析技术对其进行了结构表征。中心钴(II)离子与六个DAT分子的六个N原子配位,形成一个六配位、略微畸变的八面体结构。配离子位于两个苯环互相平行的PA离子之间。在[Co(DAT)6](PA)2∙4H2O的分子单元中,配离子和PA离子通过静电引力连接;分子单元间通过分子间氢键连接形成配合物的晶体结构,DAT配体分子对于晶体结构的形成起到了重要作用。采用TG-DTG、DSC和FT-IR分析技术对目标化合物的热分解过程进行了研究,并采用Kissinger法和Ozawa-Doyle法对目标配合物第一放热分解过程的非等温反应动力学进行了计算。  相似文献   

3.
4.
2MgO•2B2O3•MgCl2•14H2O-MgCl2-H2O体系30 ℃相平衡   总被引:1,自引:0,他引:1  
用相平衡方法研究2MgO•2B2O3•MgCl2•14H2O 在30 ℃不同质量分数MgCl2 水溶液中的溶解转化产物及其溶解度. 结果表明, 该复盐在MgCl2的质量分数0~2%浓度范围, 发生不同步溶解并转化为多水硼镁石(2MgO•3B2O3•15H2O); 在MgCl2的质量分数2%~13.8%浓度范围, 转化为柱硼镁石(MgO•B2O3•3H2O), 这一结果比文献报导的该硼酸盐的形成温度低了13 ℃,为盐湖硼酸镁矿物柱硼镁石形成的解释提供了物理化学依据; 而在MgCl2质量分数大于13.8%时同步溶解,不发生转化. 提出了溶解相转化反应机理.  相似文献   

5.
运用自动电位滴定技术分别研究了纳米α-Fe2O3、γ-Al2O3、SiO2单一体系及三组分混合体系中氧化物表面的酸碱性质和对重金属离子Cu2+、Pb2+、Zn2+的吸附行为. 依据表面配位理论恒电容模式(CCM), 计算了相应的表面酸碱配位常数. 结果表明: α-Fe2O3/γ-Al2O3/SiO2三组分混合体系的表面化学反应并非是单一体系的简单叠加, 而是存在着不同矿物表面间复杂的交互作用. 三组分表面酸碱反应平衡式和相应的酸碱反应平衡常数分别为: ≡XOH2+?≡XOH+H+ (lgKa1=-4.23), ≡XOH?≡XO-+H+(lgKa2=-8.41). 根据重金属离子Cu2+、Pb2+、Zn2+在α-Fe2O3/γ-Al2O3/SiO2混合体系表面的吸附行为, 计算得到Cu2+、Pb2+、Zn2+在混合体系表面配位反应及其平衡常数如下: ≡XOH+M2+?≡XOM++H+; lgK=-2.20, -1.90, -3.20 (M=Cu, Pb, Zn).  相似文献   

6.
The important zinc borate of 2ZnO · 3B2O3 · 3H2O has been synthesized and characterized by means of chemical analysis, XRD, FT-IR, and DTA–TG techniques. The molar enthalpies of solution of H3BO3(s) in HCl · 54.561H2O, of ZnO(s) in the mixture of HCl · 54.561H2O and calculated amount of H3BO3, and of 2ZnO · 3B2O3 · 3H2O(s) in HCl · 54.604H2O were measured, respectively. With the use of the standard molar enthalpies of formation for ZnO(s), H3BO3(s), and H2O(l), the standard molar enthalpy of formation of ?(5561.7 ± 4.9) kJ · mol?1 for 2ZnO · 3B2O3 · 3H2O(s) was obtained. Thermodynamic properties of this compound were also calculated by a group contribution method.  相似文献   

7.
Thermodynamic activity of sodium oxide and oxidation potential in NaOH—Na2O—Na2O2—H2O—NaH melt at the temperature of 400°C was investigated. Galvanic cell for the potentiometric measurements consisted either of a sodium electrode formed by β and β″-alumina semi-closed tube filled with liquid sodium or a platinum wire and of an oxygen electrode made from ZrO2 (Y2O3) solid electrolyte with the Bi—Bi2O3 reference mixture. The number of exchanged electrons determined from the electromotive force measurements was in good agreement with the assumed reactions. The activity coefficient of sodium oxide was lower than one. Voltammetric measurements were carried out with a sodium reference electrode and a nickel auxiliary electrode. Behaviour of platinum, gold, silver and nickel as working electrodes was studied. The experiments were carried out in nitrogen atmosphere. Several types of zirconia semi-closed tubes were tested for long-term measurements under the process conditions.  相似文献   

8.
硝酸镁在γ-Al2O3上的热分解及MgO/γ-Al2O3   总被引:9,自引:0,他引:9  
研究了不同载量时Mg(NO  相似文献   

9.
双外推法研究FeC2O4·2H2O脱水过程的动力学机理   总被引:2,自引:1,他引:2  
On the basis of the Coats-Redfern's integral equation and Ozawa's equation. the probable mechanism of the dehydration process of FeC2O4 2H2O was investigated using double extrapolation. The dehydration Process includes two steps. The first step is the nuclear producing and growing process(n=1.5), G(α)= [ln(1-α)]1/1.5; the second step is a two-dimensional diffusion process, G(α)=(1-α)ln(1-α)+a: the corresponding kinetic parameters were determined.  相似文献   

10.
NiO/γ-Al2O3催化剂中NiO与γ-Al2O3间的相互作用   总被引:27,自引:0,他引:27  
利用溶胶-凝胶法制备了不同含量的 NiO/γ-Al_2O_3催化剂,通过XRD,XPS和 TPR等技术考察了制备方法、NiO含量和焙烧温度对催化剂结构和Ni存在状态的影响,发现溶胶-凝胶法制备的催化剂活性组分NiO与担体γ-Al_2O_3间具有强相互作用.详细地讨论了Ni物种的还原状态与以“Ni~0”为活性中心的催化反应的活性之间的关系.溶胶-凝胶法制备的催化剂经高温焙烧后,Ni以一种类尖晶石结构的固溶体形式存在,这种固溶体态尖晶石可能会抑制Ni的烧结和流失,提高催化剂的稳定性.  相似文献   

11.
采用熔融硼酸法合成了一种具有层状结构的新型水合稀土多硼酸盐, La[B5O8(OH)(H2O)]NO3•2H2O, 并利用单晶X射线衍射技术确定了它的结构. 它属于单斜晶系, P21/n空间群. 其基本构建单元 (fundamental building block, 简称FBB)是由三个BO4和两个BO3基团所构成的一个双三元环[B5O12]基团. 结构中每一个FBB通过共顶点氧原子与周围四个同样的单元连接成具有九元环窗口的二维[B5O10]层, La3+位于九元环中心附近. [B5O10]层沿着b方向进行堆积, 硝酸根离子和结构中部分结晶水分子位于相邻的[B5O10]层之间.  相似文献   

12.
According to the compositions of the underground gasfield brines in the west of Sichuan Basin, the solu- bilities and densities of the solid-liquid equilibria in the quaternary system Na+, K+//Br-, B4O72--H2O at 298 K were determined by the method of isothermal solution saturation. From the experimental data, the phase diagram, water content diagram and density-composition diagram were obtained. This quaternary system is of simple eutectic type, without double salt and solid solution. There are two invariant points, five univariant curves, four fields of crystalli- zation in the system. The equilibrium solid phases are Na2BaO7·10H20, K2B4O7·4H2O, NaBr·2H2O and KBr. Na2B4O7·10H2O has a larger crystallization field, and NaBr·2H2O has a smaller crystallization field. It is also found that bromide has the salting-out effect on borate in the quaternary system Na+, K+//Br-, B4O72--H2Oat 298 K.  相似文献   

13.
Two fluoride sulfates,K2Mn3(SO4)3F2·4H2O(Ⅰ) and Rb2Mn3(SO4)3F2·2H2O (Ⅱ) are obtained by water solution method.Single-crystal X-ray diffraction analysis indicated that they crystallize in space groups of Cmc21.Their structures feature a pseudo-KTP structure consisting of interconnecting[Mn3(SO4)3F2(H2O)2] layers,which are further packing along the a axis with alkali metal cations balancing the charges.The structure relationships between the two compounds are discussed.Secondharmonic generation measurements manifest that Ⅰ and Ⅱ have similar second-harmonic generation responses of about 0.2 and 0.25 times that of KH2PO4.  相似文献   

14.
In order to utilize the brine resources in China, the solid-liquid equilibria in quaternary system Li+, K+//SO42-, B4O72--H2O at 288 K was studied by the isothermal solution equilibrium method. Solubilities and densities of solutions were determined experimentally. According to the experimental data, the equilibrium phase diagrams, density-composition diagram and corresponding water content diagram of the quaternary system were plotted. Double salt KLiSO4 was found in the reciprocal quaternary system Li+, K+//SO42-, B4O72--H2O at 288 K. The quaternary system has three invariant points, seven univariant curves and five fields of crystallization. The five crystallization regions correspond to Li2B4O7·3H2O, Li2SO4·H2O, K2B4O7·4H2O, K2SO4 and KLiSO4, respectively. The crystallization field of salt Li2B4O7·3H2O is the largest, whereas that of Li2SO4·H2O is the smallest. The experimental results show that Li2SO4·H2O has a strong salting-out effect on other salts.  相似文献   

15.
Different from the traditional pyrometallurgical recovery process of Li and Co from spent lithium-ion batteries, a new recovery method for Li and Co was established by converting LiCoO2 into water-soluble metal sulfates by roasting a mixture of LiCoO2 and NaHSO4·H2O. The evolution law of the mixture with increased roasting temperature was investigated by thermogravimetry-differential scanning calorimetry(TG-DSC), in situ X-ray diffraction(XRD), XRD, and X-ray photoelectron spectroscopy(XPS). The results show that the phase transition of LiCoO2 mixed with NaHSO4·H2O with increased temperature proceeded as follows:LiCoO2, NaHSO4·H2O→LiCoO2, NaHSO4→Li1-xCoO2, LiNaSO4, Na2S2O7, Na2SO4→Li1-xCoO2, Co3O4, LiNaSO4, Na2SO4→Co3O4, LiNaSO4. The reaction mechanism of this roasting process may be as follows:LiCoO2+NaHSO4·H2O→1/2Li2SO4+ 1/2Na2SO4+1/3Co3O4+1/12O2+3/2H2O, Li2SO4+Na2SO4=2LiNaSO4.  相似文献   

16.
由摩尔比分别为1:2和1:8的NiCl2·6H2O和Na2B4O7·10H2O作为反应物,合成两种非晶态镍硼酸盐,同时通过水热法合成β-Ni(OH)2.化学分析和热重-微商热重法(TG-DTG)分析结果确定两种非晶态镍硼酸盐的分子组成分别为NiO·0.8B2O3·4.5H2O和NiO·B2O3·3H2O.激光拉曼(Raman)实验结果表明镍硼酸盐样品中主要存在的硼氧阴离子为B3O3(OH)52-和B2O(OH)62-.同步辐射扩展X射线吸收精细结构(EXAFS)方法对样品进行结构解析,通过数据拟合给出样品中Ni原子周围近邻配位原子种类、配位数以及原子间距离.用不同晶体结构作为标准对两种非晶态镍硼酸盐进行拟合的结果表明,样品中Ni原子周围局域结构与Ni3B2O6晶体(ICSD No.31387)中的吻合较好.Ni原子周围配位原子为O、B和Ni,对于NiO·0.8B2O3·4.5H2O,配位数分别为5.7、3.8和3.8,配位距离分别为0.208、0.263和0.311 nm;对于NiO·B2O3·3H2O,配位数分别为6.0、4.0和4.0,配位距离分别为0.207、0.262和0.310 nm.  相似文献   

17.
NdCl3-CdCl2-HCl-H2O的相平衡及其固相化合物的研究   总被引:5,自引:0,他引:5  
测定了四元系NdCl3-CdCl2-HCl-H2O(298. 15 K) 的相平衡溶度数据, 绘制了相应的溶度图. 该四元系是由4个固相区CdCl2•H2O(原始盐)、9CdCl2•NdCl3•20H2O、5CdCl2•NdCl3•13H2O、NdCl3•6H2O(原始盐)组成的复杂体系. 用X射线粉末衍射及TG-DTG和荧光光谱对9CdCl2•NdCl3•20H2O 和5CdCl2•NdCl3•13H2O进行了研究. 荧光研究表明, 化合物9CdCl2•NdCl3•20H2O具有微弱的荧光强度, 5CdCl2•NdCl3•13H2O的荧光强度则相对大于9CdCl2•NdCl3•20H2O的. 对X射线粉末衍射进行了指标化.  相似文献   

18.
Two new alkaline metal borates containing 1D{B5}/{B6}oxoboron helical chains,namely Na0.5[B5O8(OH)2]0.5[B5O6(OH)2]0.5·0.5H3O(1)and NaKCs[B6O9(OH)3](2)were synthesized under solvothermal conditions.Compound 1 contains the interesting alternative left-and right-handed helical{[B5O8(OH)2][B5O6(OH)2]}2-({B5}-1 and{B5}-2)1D chains and compound 2 possesses the similar[B6O11(OH)3]7-({B6})chains.Their 1D chains are further assembled into 2D layers and 3D supramolecular frameworks through O-H…O hydrogen bonds.In addition,the UV cutoff edge of compounds 1 and 2 is both below 190 nm.  相似文献   

19.
Two new belt-like borates Na4[B9O14(OH)3]·0.5H2O(1) and Na5[B9O14(OH)4](2) have been synthesized under solvothermal conditions. Both compounds contain unprecedented B9O16(OH)n(n+5)-[n=3(1), 4(2)] clusters, which are constructed from four B3O3 rings via three BO4 tetrahedra. Compound 1 exhibits a rare 1D belt with two types of 8-membered ring(MR) windows based on B9O16(OH)38- clusters. Compound 2 features two different 1D belts built by different B9O16(OH)49- units, which is first discovered in borate family. UV-Vis diffuse reflectance spectra reveal that compounds 1 and 2 have the cut-off edges below 190 nm, indicating that they may have potential application in deep UV(DUV) region.  相似文献   

20.
Anew mixed alkali and alkaline-earth metal borate Na4Ca2[B14O22(OH)6]·2H2O(1) has been made under a mild solvothermal condition and characterized by single-crystal X-ray diffraction, infrared(IR) spectroscopy, UV-Vis diffuse reflectance spectroscopy, powder X-ray diffraction and thermogravimetric analysis, respectively. Compound 1 features a 1D tube based on[B14O24(OH)6]12-({B14}-1) oxo-boron clusters. Such a tube built by {B14}-1 units has been discovered for the first time in borate system. These tubes are arranged orderly to generate 2D layers and a further 3D supramolecular network through hydrogen bond interactions. UV-Vis diffuse reflectance spectrum reveals that compound 1 is a wide band-gap semiconductor and has potential application in UV region.  相似文献   

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