Thermal Behavior of N,N''''-Bis[N-(2,2,2-trinitroethyl)- N-nitro]ethylenediamine

Introduction N,N'-Bis[N-(2,2,2-trinitroethyl)-N-nitro]ethyenedi- amine (BTNEDA) is a typical nitramine compound, which is structurally shown in Figure 1. The crystal density is 1.87 gcm-3. The detonation velocity corresponding to r=1.842 gcm-3 is about 8970 ms-1.1 Therefore, BTNEDA is used as high explosive. Its thermogram has been reported.2 In this paper, its kinetic parameters of the exothermic decomposition reaction are described. This is quite useful in the evaluation of its ther…     

含二维水网的三维超分子[Ni(phen)2(H2O)2][Ni(PDC)2]•7H2O

在水溶液中合成了离子型配合物[Ni(phen)₂(H₂O)₂][Ni(PDC)₂]•7H₂O (H₂PDC＝吡啶-2,6-二甲酸, phen＝1,10-菲啰啉). 通过元素分析、红外光谱、单晶X射线衍射以及热重分析对配合物进行了表征. 晶体数据解析表明, 化合物属于三斜晶系, 空间群为P1, a＝1.0092(4) nm, b＝1.4599(6) nm, c＝1.4933(5) nm, α＝73.982(2)°, β＝78.652(2)°, γ＝75.184(3)°, V＝2.0256(13) nm³, Z＝2, F(000)＝1004, μ＝1.014 mm^－1, R₁＝0.0538, wR₂＝0.1493. 配合物中的结晶水分子形成一个(H₂O)₁₂水簇, (H₂O)₁₂水簇通过氢键连接为二维水网, 最终构成三维超分子网络.     

教学方法的探索和实践

在建设国家级精品课程无机化学与化学分析的教学实践中,强调教师教学观念的转变是全方位对学生实施素质教育的根本;开展了第二课堂建设以及大纲式教学方法等教学举措。     

分子间作用力构筑的具有柔性结构的醋氯芬酸多聚物: 晶体结构, 热稳定性, 溶解度和DFT计算

非甾体类抗炎药物醋氯芬酸(ACF)的水溶性差, 导致其生物利用度较低. 本文制备了三种多聚物, 分别是醋氯芬酸与4,4'-联吡啶(BIPY)共晶(1), 与3-氨基苯甲酸(3-ABA)盐(2)和与二甲基亚砜(DMSO)的溶剂化物(3), 利用红外光谱、粉末X射线衍射和单晶X射线衍射对它们的结构进行了表征. 结果表明, 化合物1-3的超分子结构是通过氢键、C―H…π和π…π堆积作用构筑而成, 三个多聚物具有良好的热稳定性. 从热力学角度分析和密度泛函理论(DFT)计算说明ACF在化合物3中的构象比其在化合物1和2中更稳定. 此外, ACF形成共晶、盐和溶剂化物后有效提高了其溶解度.     

L-苏糖酸锌的制备及其性质

L-苏糖酸作为金属离子的载体 ,可使金属离子易于与氨基酸或蛋白质结合而被动物吸收和利用[1] ,L -苏糖酸钙就是一种优秀的钙补充剂 ,其吸收率达 95%以上 ,是传统钙补充剂的 2～ 3倍 ,无任何毒副作用 ,1 %的 L -苏糖酸钙能使维生素 C的吸收增加 1 .8倍[2 ,3 ] .国外已有苏糖酸产品及专利[4 ] ,国内也有苏糖酸钙产品问世 .文献 [5]报道 0 .1 mol/ L苏糖酸钙在生理 p H下 ,将有 87%钙为分子状态 ,这一结果显然支持了“分子补钙”的理论 ,也是其成为优秀钙补充剂的原因 .锌是人体中必需的 1 4种微量元素之一 ,与人体中不下2 0 0种金属酶有关 …     

Thermochemistry on Coordination Behavior of Praseodymium Chloride Hydrate with Diethylammonium Diethyldithiocarbamate

The complex of praseodymium chloride lower hydrate with diethylammonium diethyldithiocarbamate (D-DDC) has been synthesized conveniently in absolute alcohol and dry N2 atmosphere. The title complex was identified as Et2NH2[Pr(S2CNEt2)4] by chemical and elemental analyses, the bonding characteristics of which were characterized by IR spectrum.The enthalpy of solution for praseodymium chloride hydrate and D-DDC in absolute alcohol at 298.15 K, and the enthalpy changes of liquid-phase reaction of formation for Et2NH2 [ Pr(S2CNEt2)4] at different temperatures were determined by miccocalorimetry. On the basis of experimental and calculated resuits, three thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy),the rate constant and three kinetic parameters (the apparent activation energy, the pre-exponential constant and the reaction order) of liquid phase reaction of formation were obtained. The enthalpy change of the solid-phase title reaction at 298.15 K was calculated by a thermochemical cycle.     

硫酸锌与α-氨基酸的相化学及其新相的合成和表征

α 氨基酸锌作为添加剂在药物、食品和化妆品等方面都有广阔的应用前景[1,2 ] 。有关氨基酸锌的合成方法前文[3] 已述及。而用相平衡方法研究锌盐与氨基酸的配合行为的相化学[4] ,对新型配合物 ,特别是固液异成分化合物的合成有指导意义。本文对ＺｎＳＯ4与人体必需而非自生的Ｌ 亮氨酸 (Ｌ Ｌｅｕ)、Ｌ 色氨酸 (Ｌ Ｔｒｙ)、Ｌ 苏氨酸 (Ｌ Ｔｈｒ)和Ｌ 缬氨酸 (Ｌ Ｖａｌ)在水中的等温溶度性质进行了研究 ,构制了其相图 ,讨论了未形成化合物的原因。合成了未见报道的Ｚｎ(Ｌｅｕ)ＳＯ4·0 .5Ｈ2 Ｏ ,Ｚｎ(Ｖａｌ)ＳＯ4·Ｈ2 Ｏ和固态配合物…     

Thermokinetic Study on the Complexation Reaction of the First-Row Transitional Metal Chlorides with Histidine

Introduction The first-row transitional metals of chromium, man-ganese, iron, cobalt, nickel and copper are essential trace elements to human body, which are connected with hundreds of metalloproteins and metalloenzymes, participating in ferment syntheses and playing an im-portant role in metabolism of nucleic acid, protein, carbohydrate and fat. L--histidine is one of the basic units of proteins and absorbed from food because of not being synthesized in human body. Therefore, it is of practic…     

Kinetics of the Exothermic Decomposition Reaction of N-Methyl-N-nitro-2,2,2- trinitroethanamine

The thermal behavior and kinetic parameters of the exothermic decomposition reaction of N-methyl-N-nitro-2,2,2-trinitroethanamine in a temperature-programmed mode have been investigated by means of differential scanning calorimetry (DSC).The kinetic equation of the exothermic decomposition process of the compound is proposed. The values of the apparent activation energy (Ea), pre-exponential factor (A), entropy of activation (ΔS^≠ ), enthalpy of activation (ΔH^≠ ), and free energy of activation (ΔG^≠ ) of this reaction and the critical temperature of thermal explosion of the compound are reported. Information is obtained on the mechanism of the initial stage of the thermal decomposition of the compound.     

L-苏糖酸铜的制备及其标准生成焓

L 苏糖酸作为金属离子的载体,可使金属离子易与氨基酸或蛋白质结合而被动物吸收和利用[1]。本文以L 苏糖酸与Cu2(OH)2CO3·xH2O反应后的溶液浓缩加无水甲醇制得水合物Cu(C4H6O5)·0 5H2O(经HPLC分析,纯度>99 9%),用化学分析、元素分析、IR光谱、TD DTG和量热法进行了表征。1　实验部分1 1　试剂与仪器L 抗坏血酸(Vc)、B.R.(东北制药总厂);H2O2、CaCO3、H2C2O4和Cu2(OH)2CO3·xH2O均为A.R.(西安化学试剂厂);2400型元素分析仪(PE公司);Cu2+含量用Na2S2O3滴定法测定;TG 7型热重分析仪(PE公司);BRUKEREQUINOX 5…