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1.
李武  高世扬 《应用化学》1995,12(4):36-39
用精密量热仪对模拟合成的MgO-27.56%MgCl-H2O浓盐溶液进行恒沸盐酸-△H滴定。发现活性MgO在27.56%MgCl-H2O溶液中不同浓度时表现出不同的结果。结合该浓盐溶液的恒混盐酸-PH滴定结果对反应机制进行了初步探讨。  相似文献   

2.
Cu-Ag-Mn-Ce-O/γ-Al_2O_3催化剂对CH_3OH及CO深度氧化时各元素的相互作用王金安,许勇,汪仁(华东理工大学工业催化研究所,上海200237)关键词Cu-Ag-Mn-Ce-O/γ-Al_2O_3催化剂,深度氧化,甲醇,一氧化碳,相互?..  相似文献   

3.
对MgO·2B_2O_3-18%MgCl_2-H_2O过饱和溶液在不同温度条件下的结晶动力学过程进行测定,给出结晶动力学方程。析出固相采用X-射线粉末衍射、红外光谱和热分析进行物相鉴定。提出使用结晶法合成章氏硼镁石的新方法。  相似文献   

4.
本文研究了含硼四元水盐体系MgB4O7-MgO4-MgCl2-H2O及次级体系MgB4O7-MgSO4-H2O和MgB4O7-MgCl2-H2O在298.15K时不同离子强度下的稀释热和热容,并将Debye-Huckel极限公式应用到多元电解质稀溶液中,获得从高离子强度到低离子强度I为19-0.0001范围内的相对表观摩尔焓.  相似文献   

5.
本文运用TPR、TPD-MS、XRD等技术研究了Mn-Ag/γ-Al_2O_3催化剂的还原性能和再氧化能力.结果表明,Mn-Ag/γ-Al_2O_3中银物相由Ag ̄0和Ag_2O组成,锰物相由β-MnO_2和Mn2O_3组成.Mn/γ-Al_2O_3催化剂的TPR有二个还原峰,分别是MnO_2和Mn_2O_3的还原.Ag促使MnO_2和Mn_2O_3的还原明显向低温方向移动,而且MnO_2和Mn_2O_3的还原峰融合成一个还原峰.Mn-Ag/γ-Al_2O_3的TPD有三个脱氧峰,随着Ag含量增加,峰Ⅰ向高温方向移动,Mn ̄(4+)2p3/2的电子结合能增加,并且催化剂的再氧化能力增强.催化剂CO的氧化活性与催化剂的再氧化能力有很好的对应关系.  相似文献   

6.
本文采用等温溶解平衡法研究了四元交互体系Li+,Mg2+/CI-,SO-H2O25℃的机关系和平衡液相的物化性质(密度、粘度、电导率、折光率和pH).该体系25℃有七个相区Li2SO4·H2O,MgSO4·7H2O.MgSO4·6H2O.MgSO4·5H2O,MgC12,6H2O,LiCI.MgCl2.7H2O,LiCI·H2O,十一条单变量线,五个共饱点.其中LiCI·H2O+LiCI·MgCl2·7H2O+Li2SO4·H2O为一致零变量点.与文献中的研究结果比较,我们得到两个新相区MgSO4·6H2O和MgSO4·5H2O.用经验和半经验公式计算了平衡液相的密度、折光率.由实验测定的溶解度数据求得了高锂浓度下的Pitzer参数.对该体系25℃溶解度进行了理论计算复证.  相似文献   

7.
标题化合物(Me_2SiSiMe_2)[η ̄5-(3-Me_3SiC_5H_3)Fe(CO)_2]_2/(μ-CO)_2(A)分子中的Fe-Fe键被钠汞齐还原断裂,生成相应的双铁负离子,分别与MeCOCl、PhCOCl、PhCH_2Cl、ClCH_2COOC_2H_5和Ph_3SnCl进行亲核取代反应,生成在铁原子上引入相应取代基的产物(Me_2SiSiMe_2)[η ̄5-(3-Me_3SiC_5H_3)Fe(CO)_2R]_2(R:MeCO(1),PhCO(2),PhCH_2(3),CH_2COOC_2H_5(4),Ph_3Sn(5),I(6))。A在氯仿中与碘反应,得到Fe-Fe断裂的双铁碘化物,但在苯中与过量碘反应,则得到Fe-I-Fe桥联的离子型化合物(Me_2SiSiMe_2)[η ̄5-(3-Me_3SiC_5H_3)Fe(CO)_2]_2I·I(7)。化合物6的晶体和分子结构经X射线衍射测定,6属单斜晶系,P21/c空间群,a=1.7217(4)nm,b=0.7753(2)nm,C=1.3629(7)nm,β=103.80(3)°,V=1.767(2)nm3,Z=4,Dc=1.6299·cm-1,最终偏差因子R=0.054。  相似文献   

8.
本文借助于DTA和X射线结构分析测定了LaCl_3-SrCl_2-MgCl_2三元体系相图,发现它属简单低共熔型,体系内有对应于LaCl_3、SrCl_2和MgCl_2的3个液相面、3条2次结晶线和1个三元低共熔点E(15.0wt%LaCl_3,49.5wt%SrCl_2,35.5wt%MgCl_2;545℃),并且在固相下有一个不稳定的化合物生成,在约500℃时分解。  相似文献   

9.
通过SnCl_2对化合物Me_2Si[η~5-C_5H_4Fe(CO)]_2(μ-CO)_2(Ⅰ)中Fe-Fe键的插入反应以及Ⅰ被Na-Hg齐还原所生成的相应双铁负离子{Me_2Si[η~5-C_5H_4Fe(CO)_2]_2}~(2-)与SnR_2Cl_2(R=Me,Ph)的亲核反应,合成了环状化合物Me_2Si[η~5-C_5H_4Fe(CO)_2]_2SnR_2[R=Cl(1),Me(2),Ph(3)]。以元素分析、IR和~1HNMR谱表征了它们的结构,并用X射线衍射测定了配合物3的晶体结构。3为单斜晶系,空间群P2_1/n,a=1.0384(3)nm,b=1.6384(1)nm,c=1.5762(5)nm,β=97.93(2)°,V=2.656(2)nm~3,Z=4,Dx=1.71g/mL。  相似文献   

10.
用紫外-可见光谱对氧化剂PhIO、H_2O_2和空气对μ-氧代双四苯基卟吩合锰([TPP·Mn(Ⅲ)]_2O)的氧化过程进行监测,揭示了[TPPMn(Ⅲ)]_2O在不同氧化剂作用下具有不同的反应过程。研究了8种取代μ-氧双四苯基卟吩合锰{[TXPPMn(Ⅲ)]_2O,X=p-(i-Pr),p-CH_3,p-Cl,p-F,p-OCH_3,H,m-Cl,o-Cl}与H_2O_2反应中的取代基效应和溶剂效应。结果表明:上述反应为卟啉环上的吸电子基所促进;且反应速率随着反应溶剂的亲核性能的增加而增加。  相似文献   

11.
Recently, a new research realm in crystal engineering of supramolecular architecturesassembled by means of coordinate covalent bonding', hydrogen bonding', or other weakintermolecular interactions= has been rapidly expanding in order to rationally developnew classes of functional materials with cavities or pores. These types of compoundsmay exhibit interesting topological structures and the clathrations of the cavity structuresmay have many potential properties such as catalysis', electrical co…  相似文献   

12.
PseudolaricacidA(l)whichexhibitsantifungalandantifertilityactivitieswasisolatedfromPeudolarl-xKaenlpjbriGord'.Theabsoluteconfigurationsofthesechiralcenterswereassignedtobe3S,4S,10RandIIRrespectively'.Accordingtotheretrosyfltheticanalysis.theskeletonofIcouldbeconstructedbyintramolecular[4- 31cycloadditiontyomaseven-memberedlactone2(Schemel)whichcouldbeobtainedfrom(6S)-6-Thesynthesisbeganwithbetalprotected0-ketoacid4,tbllowedbyamidationwith(-)-camphorsultamandDCCtoobtainapairofdiastereomer…  相似文献   

13.
Alternative Ligands. XXI. Novel Donor/Acceptor Ligands Me2PCH2CH2SiFnMe3-n, Me2PCH2CH2SiR(C6H4F)2, and (2-Me2PC6H4)SiXMe2 Donor/acceptor ligands of the type Me2PCH2CH2SiX3 [X = Cl ( 1 ), F ( 2 ), Me ( 3 ), OMe ( 4 )], (Me2PCH2CH2)2SiX2 [X = Cl ( 6 ), F ( 7 )], Me2PCH2CH2SiX(C6H4F)2 [X = F ( 5 ), Me ( 8 )], and Me2PCH2CH2SiXnMe3-n[n = 1; X = Cl ( 10 ), F ( 11 ); n = 2; X = F ( 9 )] are prepared in yields between 42 and 95% by photochemical addition of Me2PH to the corresponding vinylsilane precursors. In case of the halogen containing representatives formation of solid polyadducts, due to Lewis acid/base interaction between P-donor and Si-acceptor function, reduces the yields. Ligands of the type (2-Me2PC6H4)SiXMe2 [X = NMe2 ( 12 ), Cl ( 13 ), F ( 14 )] are obtained by two different routes (Abb. 3), using 2-chlorobromobenzene as the starting material. New compounds have been characterized by analytical (C, H) and spectroscopic (NMR, MS) investigations. In order to elucidate the associative properties compounds 2 and 9 were used for the following experiments:
  • – Study of the influence of dissolution on the proton and fluorine resonances of 2 and 9 ,
  • – investigation of the adduct equilibrium (–H2CF3Si←PMe2CH2–)n + nBF3 → n[F3B←PMe2CH2CH2SiF3],
  • – cleavage of the polyadduct of 2 using [NH4]F and [Me4N]F, respectively, for the formation of hexacoordinate complex anions [Me2PCH2CH2SiF5]2?.
The results obtained confirm the assumption that oligo- and polymerisation are due to P→Si interaction.  相似文献   

14.
1-硫脲乙基-2-芳基-2-咪唑啉化合物的合成刘运廷,章荣玲(山东工业大学数理系济南,250014)关键词咪唑啉,硫脲基,芳基,合成咪唑啉衍生物由于具有缓蚀、杀菌、抗癌等活性而迅速发展 ̄[1,5]。作者曾研究过各种咪唑啉衍生物的合成 ̄[6],系采用通...  相似文献   

15.
Gas Phase Reactions of H3PF2: Synthesis of the Monohalogenophosphanes H2PF and H2PCl Gas phase reactions of H3PF2 at ≤ 10 mbar with hydrides (B2H6, HSi(CH3)3, HSn(CH3)3), amines (H3N, N(CH3)3) and electrophilic halides of B, Si and Ti in the beam of an IR interferometer have been investigated with a time delay of 15 sec. between successive measurements. Gas/solid phase reactions of H3PF2 with KF and AlCl3 and reactions of H3PF3 and HPF4 have been studied similarly. With H3N, N(CH3)3 and electrophilic halides, H3PF2 was converted into its dehydrofluorination product H2PF. This eliminates further HF in the presence of H3N or N(CH3)3, while BCl3 or TiCl4 yield the hitherto unknown H2PCl. The IR spectra of the short-lived species H2PF and H2PCl as well as their deuterated isotopomers, which reveal at room temperature and ≤ 10 mbar a halflife time of ≤ 12 min. and ≤ 50 sec. respectively, were recorded and analysed in order to characterize the novel species.  相似文献   

16.
17.
2BaC2O4 · H2O (M = 468.73) is triclinic, space group P1, with a = 9.312(1) A?, b = 9.649(1) A?, c = 6.188(1) A?, α = 90.13(2)°, β = 95.36(2)°, γ = 125.18(2)°, Z = 2, Dm = 3.48; Cx = 3.51g · cm?3. The position of the Ba atom was determined from a Patterson function. A subsequent Fourier synthesis clearly revealed the position of all C and O atoms in the structure. Refinement of the MoKα diffractometer data by a least-squares method using full matrix gave R = 0.065. The structure presents two remarkable characteristics: (a) We distinguish two types of (C2O4)2? ions. The first are planar, the second are notably separated from the plane configuration (deviation = 30°); this deformation is of a steric origin. (b) The water molecules are located in channels parallel to [001]. They enter in the coordination of one of the Ba2+ ions but do not exchange any strong hydrogen bond with oxygen atoms which surround them.  相似文献   

18.
19.
The preparation and resolution of two new axially chiral quinazoline-containing phosphinamine ligands, 2-(2-pyridyl)-Quinazolinap and 2-(2-pyrazinyl)-Quinazolinap, is described. The ligands were synthesised in good yield over eight steps and included two Pd-catalysed reactions, a Suzuki coupling to form the biaryl linkage and the introduction of the diphenylphosphino group, as the key transformations. The racemic ligands were resolved via the fractional crystallisation of diastereomeric palladacycles derived from (+)-di-μ-chlorobis{(R)-dimethyl[1-(1-naphthyl)ethyl]aminato-C2,N}dipalladium (II) X-ray crystal structures of the (S,R)-2-pyridyl- and (S,R)-2-pyrazinyl-palladacycles are included. Displacement of the resolving agent by reaction with 1,2-bis(diphenylphosphino)ethane gave enantiopure 2-(2-pyridyl)-Quinazolinap and 2-(2-pyrazinyl)-Quinazolinap, new atropisomeric phosphinamine ligands for asymmetric catalysis. These ligands were applied in the palladium-catalysed allylic substitution of 1,3-diphenylprop-2-enyl acetate resulting in moderate conversions and enantioselectivities of up to 81%.  相似文献   

20.
Treatment of Ir2Cl2(C8H14)4 with the phosphines t-Bu3?nP(CH2CMe3)n (n = 3,2,1) in hot toluene followed by crystallization of the products from C7H8/ EtOH mixtures gave the cyclometallated hydrides (C8H14)2Ir-μ-Cl2IrH[CH2CMe2CH2P(CH2CMe3)2][P(CH2 (I) [t-BuP(CH2CMe3)2]2H2Ir-μ-Cl2IrH[CH2CMe2CH2PBut(CH2CMe3)][t-BuP(CH2CMe3)2] (II), and [(t-Bu2PCH2CMe2CH2)HIrCl]2 (III). The dihydrides IrH2Cl[t-BuP(CH2CMe3)2]2 (IIa) and IrH2Cl(t-Bu2PCH2CMe3)2 (IIIa) were also isolated; these species were, however, more conveniently obtained by bubbling hydrogen through the solution of Ir2Cl2 (C8H14)4 and the respective phosphine in toluene. i-Pr3 reacted with the olefiniridium(I) precursor in C7H8/EtOH to yield the carbonyl complexes (i-Pr3P)2H2Ir-μ-Cl2Ir(CO)(PPri3)2 (IV) and IrCl(CO)(PPi3)2 (IVa), no cyclometallated product being detected. The stereochemistries of the complexes were deduced from IR, 1H, 31P, and 13C NMR data. The crystal structures of IIIa and IVa were also determined.  相似文献   

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