A novel flower-like hydrated magnesium carbonate hydroxide, Mg5 （CO3 ）4 （OH）2·4H2O, with micro-structure composed of individual thin nano-sheets was synthesized using a facile solution route without the use o...A novel flower-like hydrated magnesium carbonate hydroxide, Mg5 （CO3 ）4 （OH）2·4H2O, with micro-structure composed of individual thin nano-sheets was synthesized using a facile solution route without the use of template or organic surfactant. Reaction time has an important effect on the final morphology of the product. The micro-structure and morphology of Mg5 （CO3）4 （OH）2·4H2O were characterized by means of X-ray diffractometry （XRD）, fieldemission scanning electron microscopy（FE-SEM）. Brunauer-Emmett-Teller（BET） surface areas of the samples were also measured. The probable formation mechanism of flower-like micro-structure was discussed. It was found that Mg5 （CO3）4（ OH）2·4H2O with flower-like micro-structure was a novel and efficient catalyst for the synthesis of diphenyl carbonate （DPC） by transesterification of dimethyl carbonate （DMC） with phenol.展开更多
Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part i...Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part icles were characterized by powder X ray diffraction(XRD),thermal analysis(TGA DSC), infrared spectroscopy(FT IR),transmission electron microscopy(SEM) and scanning electron microscopy(TEM). The size distribution in whisker like and nanocrystalline materials arein the range of 10～50μm and 10～20nm respectively. The whisker MOS is metastable phase in MgSO4 NaOH H2O system at 140℃,whereas nanometer MOS is stable phase.展开更多
Nanocrystalline MgSO\-4·5Mg（OH）\-2·3H\-2O were prepared by the hydrothermal reaction at 140 ℃ for 24 h. Nanoparticle samples were characterized by FTIR, TG, DSC, XRD and TEM. The size distribution of nano...Nanocrystalline MgSO\-4·5Mg（OH）\-2·3H\-2O were prepared by the hydrothermal reaction at 140 ℃ for 24 h. Nanoparticle samples were characterized by FTIR, TG, DSC, XRD and TEM. The size distribution of nanocrystalline is in the range of 10\20 nm, the mean size is 16 nm.展开更多
The new mixed borates with formula(Rb 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O and Cs 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O)were prepared by reaction Rb (Cs )-borate aqueous solution with CaCl 2 .Two kinds of compounds w...The new mixed borates with formula(Rb 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O and Cs 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O)were prepared by reaction Rb (Cs )-borate aqueous solution with CaCl 2 .Two kinds of compounds were characterized by chemical analysis,X-ray powder dif fraction,FT-IR spectra and thermal analysis.展开更多
A new compound 2 6[Co(H 2O) 2(VO) 8(OH) 4(PO 4) 8] has been hydrothermally synthesized. Single crystal X-ray analysis indicates that this compound crystallizes in a monoclinic system, space group P2 1/n with a=1.438 5...A new compound 2 6[Co(H 2O) 2(VO) 8(OH) 4(PO 4) 8] has been hydrothermally synthesized. Single crystal X-ray analysis indicates that this compound crystallizes in a monoclinic system, space group P2 1/n with a=1.438 5(3) nm, b=1.012 2(2) nm, c=1.832 5(4) nm, β=90.21°, V=2\^668 2(9) nm 3, Z=2, D c=2.112 g/cm 3, R=0.055, wR=0.149 7, S=1.037. The structure of 2 6[Co(H 2O) 2(VO) 8(OH) 4(PO 4) 8] is characterized by P-V-O layers constructed by [(VO) 4(OH) 2(PO 4) 4] 6- non-symmetric units. The P-V-O layers are pillared by [Co(H 2O) 2] 2+ group, resulting in the channels within which the protonated diaminoethane and H 3O + are located.展开更多
文摘采用水热法改变Na OH体积制备了不同形貌的Ca Ti2O4(OH)2粉体,利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对样品进行了微观结构分析,并利用紫外-可见吸收测试仪对样品的吸收边进行了测试与分析。研究不同Na OH体积对Ca Ti2O4(OH)2片状结构的发育与生长、产率和光催化性能的影响。结果表明:随着Na OH体积的增加,有利于Ca Ti2O4(OH)2片状结构的发育与生长,并在(040)、(251)、(371)晶面上具有择优生长的习性,使得Ca Ti2O4(OH)2产率可达到94.2%。然而,所制备样品的光吸收与光催化性能却随着Na OH体积的增加反而降低。当加入2.4 m L Na OH所制备样品在紫外可见光下120 min对罗丹明B的分解率达到93.7%。
基金Supported by the National Natural Science Foundation of China(Nos.20671011,20331010,90406002and90406024)the 111 Project(No.B07012)the Key Laboratory of Structural Chemistry Foundation(No.060017).
文摘A novel flower-like hydrated magnesium carbonate hydroxide, Mg5 （CO3 ）4 （OH）2·4H2O, with micro-structure composed of individual thin nano-sheets was synthesized using a facile solution route without the use of template or organic surfactant. Reaction time has an important effect on the final morphology of the product. The micro-structure and morphology of Mg5 （CO3）4 （OH）2·4H2O were characterized by means of X-ray diffractometry （XRD）, fieldemission scanning electron microscopy（FE-SEM）. Brunauer-Emmett-Teller（BET） surface areas of the samples were also measured. The probable formation mechanism of flower-like micro-structure was discussed. It was found that Mg5 （CO3）4（ OH）2·4H2O with flower-like micro-structure was a novel and efficient catalyst for the synthesis of diphenyl carbonate （DPC） by transesterification of dimethyl carbonate （DMC） with phenol.
文摘Both whisker and nanometer MgSO4·5Mg(OH)2·3H2O(MOS) were prepared by hydrothermal method at 140℃for different times, using NaOH and MgSO4·7H2O as raw materials. The MgSO4·5Mg(OH)2·3H2O part icles were characterized by powder X ray diffraction(XRD),thermal analysis(TGA DSC), infrared spectroscopy(FT IR),transmission electron microscopy(SEM) and scanning electron microscopy(TEM). The size distribution in whisker like and nanocrystalline materials arein the range of 10～50μm and 10～20nm respectively. The whisker MOS is metastable phase in MgSO4 NaOH H2O system at 140℃,whereas nanometer MOS is stable phase.
文摘Nanocrystalline MgSO\-4·5Mg（OH）\-2·3H\-2O were prepared by the hydrothermal reaction at 140 ℃ for 24 h. Nanoparticle samples were characterized by FTIR, TG, DSC, XRD and TEM. The size distribution of nanocrystalline is in the range of 10\20 nm, the mean size is 16 nm.
文摘The new mixed borates with formula(Rb 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O and Cs 2 Ca [B 4 O 5 (OH) 4 ] 2 ·8H 2 O)were prepared by reaction Rb (Cs )-borate aqueous solution with CaCl 2 .Two kinds of compounds were characterized by chemical analysis,X-ray powder dif fraction,FT-IR spectra and thermal analysis.
文摘A new compound 2 6[Co(H 2O) 2(VO) 8(OH) 4(PO 4) 8] has been hydrothermally synthesized. Single crystal X-ray analysis indicates that this compound crystallizes in a monoclinic system, space group P2 1/n with a=1.438 5(3) nm, b=1.012 2(2) nm, c=1.832 5(4) nm, β=90.21°, V=2\^668 2(9) nm 3, Z=2, D c=2.112 g/cm 3, R=0.055, wR=0.149 7, S=1.037. The structure of 2 6[Co(H 2O) 2(VO) 8(OH) 4(PO 4) 8] is characterized by P-V-O layers constructed by [(VO) 4(OH) 2(PO 4) 4] 6- non-symmetric units. The P-V-O layers are pillared by [Co(H 2O) 2] 2+ group, resulting in the channels within which the protonated diaminoethane and H 3O + are located.
