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1.
用精密量热仪对模拟合成的MgO-27.56%MgCl_2-H_2O浓盐溶液进行恒沸盐酸-△H滴定。发现活性MgO在27.56%MgCl_2-H_2O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沸盐酸-pH滴定结果对反应机制进行了初步探讨。  相似文献   

2.
测定了25℃时三元体系MgCl2-CO(NH2)2-H2O的等温溶度及饱和溶液的折光率和密度,且绘制成溶度图和性质,组成图,在三元体系内形成2个三元化合物新相,MgCl2.CO(NH2)2.4H2O(记作A)和MgCl2.4CO(NH2).2H2O(记作B),B为新化合物,三元体系的溶度图由4支单饱和线(对应单饱和因相为MgCl2.6H2O,三元化合物A和B,CO(NH2)2)组成,这4支单饱和线  相似文献   

3.
四元体系CsCl—PrCl3—13%HCl—H2O(25℃)和CsCl—PrCl3—42%H…   总被引:1,自引:0,他引:1  
测定了四元体系CsCl-PrCl3-13%HCl-H2O(25℃)和CsCl-PrCl3-42%HAc-H2O(30℃)的稳定平衡态的溶液数据,绘制了相应的溶度图,两个体系的皆中有4种固相,CsCl,PrCl3.6H2O2种原始盐和CsCl.PrCl3.6H2O,3CsCl.PrCl3.7H2O2种复盐,证实了文献中对Meyer反应1机理的解释,并对新相进行了热分析,X射线粉末衍射及偏光显微镜测定  相似文献   

4.
氯碳酸镁盐的溶解、转化机制及动力学研究   总被引:7,自引:0,他引:7  
采用NH4HCO3溶液逐滴加入浓的MgCl2水溶液中,经回流沸腾制得氯碳酸镁盐的晶体2MgCO3.Mg(OH)2.MgCl2.6H2O。  相似文献   

5.
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   

6.
对MgO.2B2O3-18%MgCl2-H2O过饱和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   

7.
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   

8.
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   

9.
以NaOH,Na2CO3混合或以NH4OH,(NH4)2CO3混合液为沉淀制备了Mg/Al=3-6.7的Mg-Al为滑石。将水滑石在500-600℃下焙烧制得了具有与Mgo相同的晶体结构的Mg(Al)L复合氧化物,它们的比表面积大于或接近γ-Al2O3,而且具有良好的热稳定性。  相似文献   

10.
MgO·2B2O3-18%MgCl2-H2O过饱和溶液于20℃恒温静置,其结晶过程分为两个阶段.第一阶段结晶析出三方硼镁石(MgO·3B2O3·7.5H2O),第二阶段析出章氏硼镁石(MgO·2B2O3·9H2O).未得到多水硼镁石和库水硼镁石.探讨了两种析出团相的结晶机理并拟合出结晶动力学方程.结果表明,两种固相结晶机理均为多核表面反应控制生长.  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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