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1.
在三异丁基铝催化下DL-丙交酯与2-氢-2-氧-1,3,2-二氧磷杂环己烷开环共聚,制备了一类新型水溶性共聚物P(LA-co-TMP)。用1HNMR、IR谱对其结构进行了表征,并研究了催化剂用量及不同单体配比对总转化率、共聚物组成及特性粘度的影响。  相似文献   

2.
以丙烯酰胺(AM),丙烯酸甲酯(MA)和2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为原料,通过水溶液共聚,合成了一种新的三元共聚物。研究了影响共聚反应的因素,并对其结构进行了表征。  相似文献   

3.
首次报道了2-(2’-羟基苯基)苯并恶唑(HBO)分子在若干高分子固体膜中的电子光谱和激发态分了内质子转移(ESIPT)的特性,并与溶液体系中的相应特性进行了比较,提示的新的吸收和发射带,并讨论了高分子基质对这些特性和影响和作用机制。  相似文献   

4.
α-甲基丙烯酸2,3-环氧丙基酯与■-甲基丙烯酸甲酯嵌段共聚物的合成与鉴定张洪敏侯元雪程■(北京化工大学高分子系北京100029)关键词■-甲基丙烯酸2,3-环氧丙基酯,甲基丙烯酸甲酯,嵌段共聚物■-甲基丙烯酸2,3-环氧丙基酯(EPMA)含有两个可...  相似文献   

5.
研究了新显色剂2-(2-噻唑偶氮)-5-[(N,N-2羧基甲基)氨基]苯酚(TADCAP)与金属离子的显色反应,着重探讨了试剂与Fe ̄(3+)、Co ̄(2+)、Ni ̄(2+)、Cu ̄(2+)、Zn ̄(2+)、Mn ̄(2+)显色反应的最佳条件,测定了这些络合物的络合比和稳定常数等,同时建立了钴的分析方法,并用于维生素B_(12)注射液中Co ̄(2+)的测定。  相似文献   

6.
以碘化-N-甲基-2-氯吡啶盐为缩合剂,在三乙胺存在下由3-(2-环戊酮基)丙酸及3-(2-环己酮基)丙酸分别同四氢噻唑-2-硫酮反应,得到新化合物N-(2-环戊酮基内酰基)四氢噻唑-2-硫酮(2a)及N-(2-环己酮基丙酰基)四氢噻唑-2-硫酮(2b),产率分别为52.9%和51.0%,2a,b分别同甲醇、乙醇反应得到相应的3-(2-环戊酮基)丙酸酯3a,b及3-(2-环己酮基)丙酸酯3c,d,3a~d的产率为75~87%;2a、b分别同胺反应得到3-(2-环戊酮基)内酰胺4a、b及3-(2-环己酮基)内酰胺4c、d,4a~d产率为78~93%。  相似文献   

7.
通过3-乙氧甲酰基-4-羟基-2-氢(甲基)-2H-1,2-苯并噻嗪-1,1-二氧化物与取代嘧啶胺或均三嗪胺的胺解反应,合成了标题化合物。生物活性测定结果表明多数化合物具有较好的除草活性,部分化合物显示好的植物生长调节活性和抗炎免疫活性。  相似文献   

8.
1,2,4-三嗪类化合物的研究(ⅩⅫ)──咪唑并-(5,4-e)-1,2,4-三嗪衍生物的合成沙耀武,蔡孟深(北京医科大学药学院,北京,100083)关键词乙二脒腙,原甲酸三乙酯,1,2,4-三嗪,咪唑并-(5,4-e)-1,2,4-三嗪天然碱基拮抗...  相似文献   

9.
2,3-二氰基-2,3-二(X-取代苯基)丁二酸二乙酯在苯乙烯中的分解动力学研究齐陈泽,吴靖嘉,段大勇,贾志胜,张斌,杨第伦(兰州大学应用有机化学国家重点实验室,兰州大学化学系,兰州,730000)关键词2,3-二氰基-2,3-二(X-取代苯基)丁二...  相似文献   

10.
在0.2mol·L ̄(-1)NH_4Cl-NH_3·H_2O底液中,(pH为9.26),得到一个极为灵敏的Fe(Ⅲ)-TEA-5-Br-PADAP-H_2O_2配合吸附催化波,其峰电位为-0.71V(vs.SCE)。铁浓度在1.8×10 ̄(-10)~5.4×10 ̄(-6)mol·L ̄(-1)范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究,证明是一种配合吸附催化波,并成功地应用于各类水样,钒催化剂中微量或痕量铁的测定。  相似文献   

11.
Scandium magnesium gallide, Sc2MgGa2, and yttrium magnesium gallide, Y2MgGa2, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo2FeB2‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc2MgGa2 was determined from single‐crystal diffraction intensities and the isostructural Y2MgGa2 was identified from powder diffraction data.  相似文献   

12.
13.
On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.  相似文献   

14.
15.
[(n‐Bu)2Sn(O2PPh2)2] ( 1 ), and [Ph2Sn(O2PPh2)2] ( 2 ) have been synthesized by the reactions of R2SnCl2 (R=n‐Bu, Ph) with HO2PPh2 in Methanol. From the reaction of Ph2SnCl2 with diphenylphosphinic acid a third product [PhClSn(O2PPh2)OMe]2 ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P21/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)2 linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed.  相似文献   

16.
Summary The ability of [MoS4]2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe2+. The present study has been restricted to linear complexes such as (NEt4)2 [Cl2FeS2MoS2] and (NEt4)2[Cl2FeS2MoS2FeCl2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl2]2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl4Fe2MoS4]2–[Cl2FeMoS4]2–+FeCl2. The equilibrium constant, KD, was evaluated by differential pulse polarography. KD is tightly related to the donor number of the solvent.  相似文献   

17.
18.
The structures of the hypophosphites KH2PO2 (potassium hypophosphite), RbH2PO2 (rubidium hypophosphite) and CsH2PO2 (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous.  相似文献   

19.
Me2Sn(O2PPh2)2 ( 1 ), Ph2Pb(O2PMe2)2 ( 2 ), and Ph2Pb(O2PPh2)2 ( 3 ) have been synthesized by the reactions of Me2SnCl2 or Ph3PbCl with the corresponding diorganophosphinic acid in methanol. X‐ray diffraction studies show that the diorganophosphinate groups behave as double bridges between the metal atoms leading to polymeric ring‐chain structures with M2O4P2 (M = Pb, Sn) eight‐membered rings. The organic groups bonded to the metal atoms are in trans‐position in the resulting octahedral arrangement around the metal atoms. The IR and the mass spectra were reported and discussed.  相似文献   

20.
TG and DTA studies on Me3SnO2PCl2, Me2Sn(O2PCl2)2 and Ph3SnO2PCl2 were carried out under dynamic argon atmosphere. The results show that the decomposition proceeds in different stages leading to the formation of Sn3(PO4)2 as a stable product. This compound was characterized by IR spectroscopy. Decomposition schemes involving reductive elimination reactions were proposed.  相似文献   

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