Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly re...Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly rely on traditional bottom-up method,which involves tedious steps,time-consuming treatments,or additional alkaline media,and is unfavorable for high-efficiency production.Herein,we present a facile,ultrafast and general avenue to synthesize transition metal hydroxides on carbon substrate within 13 s by Joule-heating method.With high reaction kinetics caused by the instantaneous high temperature,seven kinds of transition metal-layered hydroxides(TM-LDHs)are formed on carbon cloth.Therein,the fastest synthesis rate reaches~0.46 cm^(2)s^(-1).Density functional theory calculations further demonstrate the nucleation energy barriers and potential mechanism for the formation of metal-based hydroxides on carbon substrates.This efficient approach avoids the use of extra agents,multiple steps,and long production time and endows the LDHs@carbon cloth with outstanding flexibility and machinability,showing practical advantages in both common and micro-zinc ion-based energy storage devices.To prove its utility,as a cathode in rechargeable aqueous alkaline Zn(micro-)battery,the NiCo LDH@carbon cloth exhibits a high energy density,superior to most transition metal LDH materials reported so far.展开更多
A novel phosphorus-nitrogen containing intumescent flame retardant (P-N IFR) was prepared via the reaction of dichlor-opentate with N-methylaniline. The structure of the product was confirmed by ^1H NMR, ^31p NMR, M...A novel phosphorus-nitrogen containing intumescent flame retardant (P-N IFR) was prepared via the reaction of dichlor-opentate with N-methylaniline. The structure of the product was confirmed by ^1H NMR, ^31p NMR, MS and IR. TGA analysis showed it has effective thermal stability.展开更多
One novel binuclear copper(Ⅱ) complex [Cu 2 (Hpt) 2 (CO 3) 2 (H 2 O) 2 ]·H 2 O with copper carbonate and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) was hydrothermally synthesized and characterized by IR a...One novel binuclear copper(Ⅱ) complex [Cu 2 (Hpt) 2 (CO 3) 2 (H 2 O) 2 ]·H 2 O with copper carbonate and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) was hydrothermally synthesized and characterized by IR and X-ray diffraction analysis.The complex crystallizes in triclinic,space group P2 1 /n with a=0.6862(1),b=0.7805(1),c=1.1983(2) nm,α=72.03(2),β=107.72(3),γ=75.28(2)o,V=0.5884 nm 3,D c=2.105 g/cm 3,Z=1,F(000)=357,GOOF=1.041,the final R=0.01859 and wR=0.04348.The whole molecule is composed of two cooper ions,two Hpt molecules,two carbonate and three water molecules,forming a binuclear structure.The crystal structure shows that the cooper ion is coordinated with three nitrogen atoms from two Hpt molecules,two oxygen atoms from one carbonic acid and one water molecule,forming a distorted square pyramidal geometry.The TG analysis result shows that the title complex is stable under 131.0 ℃.展开更多
A new 3d-4fheterometallic polymer {[Sm2Cu(PDC)2(SO4)2(H20)6]·2H2O}n 1 has been synthesized by Sm2O3, Cu(SO4)2·5H2O and pyridine-3,5-dicarboxylic acid under hydrothermal conditions. The compound cryst...A new 3d-4fheterometallic polymer {[Sm2Cu(PDC)2(SO4)2(H20)6]·2H2O}n 1 has been synthesized by Sm2O3, Cu(SO4)2·5H2O and pyridine-3,5-dicarboxylic acid under hydrothermal conditions. The compound crystallizes in triclinic system, space group Pi, with a = 6.352(7), b = 10.040(10), c = 10.315(11) A, α = 94.958(14), β = 95.556(7), γ = 99.747(14)°, V = 641.7(12)A3, Z = 1, M, = 1030.63, Dc= 2.651 Mg/m3,μ = 5.615 mm-1, F(000) = 491, the final R = 0.0491 and wR = 0.1345 for 2098 observed reflections with I 〉 2σ(I). The compound is a three-dimensional network structure in which infinite lanthanide-carboxylate chains are linked by [Cu($04)2]2- metalloligands to form a mixed-metal coordination network.展开更多
A new energetic organic potassium salt bis(dinitromethyl)difurazanyl ether potas- sium salt [K2(BDFE)] was synthesized, and structurally characterized by elemental analysis, IR spectra, t3C NMR and single-crystal ...A new energetic organic potassium salt bis(dinitromethyl)difurazanyl ether potas- sium salt [K2(BDFE)] was synthesized, and structurally characterized by elemental analysis, IR spectra, t3C NMR and single-crystal X-ray diffraction. K2(BDFE) crystallizes in monoclinic system, space group C2/c with a = 17.342(3), b = 12.6943(17), c = 8.0972(11) A, β = 110.630(2)°, V = 1668.3(4) A3, Z = 4, Dc = 2.000 g/cm3, F(000) = 1000,μ= 0.675 mm-1, S = 1.058, the final R = 0.0499 and wR = 0.1452. The K ion is eight-coordinated with eight O atoms from one water molecule and four bis(dinitromethyl)difurazanyl ethers (BDFE), forming a distorted dodecahedral structure. Thermal decomposition of the title complex was studied by using DSC and TG-DTG. There are primarily two exothermic decomposition processes between 200 and 370 ℃.展开更多
The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate (CTriMATT) were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, ...The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate (CTriMATT) were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Ultraviolet visible (UV-Vis) spectra. The results showed that the as-synthesized CTriMATT had high purity and good crystallinity. The introduction of alkyl groups induced a shift of the stretching vibration band of W-S bond to lower wavenumber, while it had no influence on the position of WS4^2-. Thermogravimetric analysis (TG), differential thermal analysis (DTA) and in situ XRD characterizations revealed that CTriMATT began to decompose at 423 K in nitrogen and was converted to WS2 eventually. In addition, the decomposition product of CTriMATT at 673 K in nitrogen was characterized by N2 adsorption (BET) and scanning electron microscopy (SEM). The results demonstrated that WS2 with higher specific surface area, and pore volume could be obtained from the thermal decomposition of CTriMATT in nitrogen.展开更多
A dinuclear complex Cd2(dnba)4(pyridine)4 (dnba = 3,5-dinitrobenzoate) has been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction, elemental analysis, FT-IR spectroscopy, D...A dinuclear complex Cd2(dnba)4(pyridine)4 (dnba = 3,5-dinitrobenzoate) has been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction, elemental analysis, FT-IR spectroscopy, DSC and TG-DTG techniques. The complex with empirical formula C48H32Cd2NI2024 (Mr = 692.83) crystallizes in monoclinic, space group P21/n with a - 12.0344(14), b = 10.5752(13), c = 21.578(3) A, β = 104.150(2)°, V = 2662.8(6) A^3, Z = 2, D, = 1.728 g/cm^3,μ(MoKa) = 0.897 mm^-1, F(000) = 1384, S = 1.016 and (△/σ)max = 0.001. R = 0.0638 and wR = 0.0737 for all data; the final R = 0.0337 and wR = 0.0644. In this complex, four carboxylates are bidentate-or chelate-coordinated with the Cd(Ⅱ) centers to give the dinuclear structure. The other coordination positions of Cd(Ⅱ) are occupied by the lone pair electrons from N of four pyridines. Thermal analyses DSC and TG-DTG have been used to determine the thermal decomposition mechanism of the title complex.展开更多
A novel manganese(Ⅱ) coordination polymer [Mn(L^1)2(H2O)]·2H2O (HL^1 = 2,6- dichlorobenzoic acid) 1 has been synthesized and structurally characterized. X-ray diffraction analyses reveal that 1 is a one-...A novel manganese(Ⅱ) coordination polymer [Mn(L^1)2(H2O)]·2H2O (HL^1 = 2,6- dichlorobenzoic acid) 1 has been synthesized and structurally characterized. X-ray diffraction analyses reveal that 1 is a one-dimensional chain structure bridged by water molecules and 2,6- dichlorobenzoic acid. The crystal is of monoclinic, space group P21/c with α = 12.9701(19), b = 20.592(3), c = 7.3759(10) A, β = 102.660(2)°, V = 1.9221(5). nm^3, Z = 4, C14H12Cl4MnO7, Mr= 488.98, Dc= 1.690 g/cm^3, p = 1.275 mm^-1, F(000) = 980, Rint = 0.0348, R = 0.0350, and wR = 0.0755. In the crystal the manganese atom is six-coordinated by two oxygen atoms from water and four oxygen atoms from four 2,6-dichlorobenzolate molecules, completing an octahedral geometry.展开更多
A new complex has been synthesized with o-methylbenzoyl-benzoic acid(HL) and 1,10-phenanthroline(phen) in the mixture of water and ethanol. It crystallizes in monoclinic, space group C2/c with a = 13.6328(18), b...A new complex has been synthesized with o-methylbenzoyl-benzoic acid(HL) and 1,10-phenanthroline(phen) in the mixture of water and ethanol. It crystallizes in monoclinic, space group C2/c with a = 13.6328(18), b = 17.7876(18), c = 19.998(2), β = 104.720(4)o, C54H48N4O11Zn, Mr = 994.33, V = 4690.2(9)3, Dc = 1.408 g/cm3, Z = 4, F(000) = 2072, μ(MoKα) = 0.59 mm-1, R = 0.0736 and wR = 0.2029. The crystal structure shows that the zinc ions are coordinated with two oxygen atoms from two HL molecules and four nitrogen atoms from two phen molecules, forming distorted octahedral coordination geometry. The fluorescent and thermal stability properties of the complex are studied. The result shows that it has one fluorescent emission band at around 412 nm. In addition, the complex is stable under 210 ℃.展开更多
A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulati...A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulation structure. How to use the general thermal response factors and z-transfer function coefficients toca1culate the indoor air temperature variation directly is also studied. It is shown through practical use that it iseasy to program with the methods presented in this paper and the calculated results are reliable.展开更多
Application of the Semenov theory of spontaneous ignition to evaluation of the critical temperature (Tc) in thermal explosion (TE) synthesis was conducted with the Ti-75at pct Al binary system using nonisothermal diff...Application of the Semenov theory of spontaneous ignition to evaluation of the critical temperature (Tc) in thermal explosion (TE) synthesis was conducted with the Ti-75at pct Al binary system using nonisothermal differential scanning calorimetry (DSC) at different heating rates. And the critical temperature for isothermal TE is predicted to be 728.9癈 by the multiple linear regression of Tcs evaluated according to Semenov theory, which is close to the range of 740~745癈 obtained from the isothermal DSC observation. This result proves that Semenov theory of spontaneous ignition is also feasible for TE synthesis in binary metallic systems like Ti-75 at. pct Al system.展开更多
A natural mineral, lindgrenite Cu3 ( MoO4 )2 ( OH)2, was synthesized from a mixture of sodium molybdate, copper sulfate, and morpholine in water under autogenous pressure at 170 ℃. The crystal structure of the mi...A natural mineral, lindgrenite Cu3 ( MoO4 )2 ( OH)2, was synthesized from a mixture of sodium molybdate, copper sulfate, and morpholine in water under autogenous pressure at 170 ℃. The crystal structure of the mineral was determined and the final refinement for 791 observed reflections with Ⅰ 〉 2σ(Ⅰ) gave R1 = 0. 0205 and wR2 = 0. 0496. The thermal stability of the mineral was investigated by using TG-DTA and variable-temperature in situ X-ray diffraction(XRD) techniques. The crystalline Cu3Mo2O9 was obtained when the mineral underwent thermal dehydration at a temperature ranging from 300 to 400 ℃, and the mixture of MoO3 and CuO was formed through decomposition of Cu3Mo2O9 at a temperature ranging from 650 to 700 ℃. Therefore, the structure of the mineral was thermally unstable at above 300 ℃, suggesting that Lindgrenite was likely formed via the hydrothermal route occurring in the nature.展开更多
A simple, convenient and efficient method for the synthesis of 1,2,4,5-tetrasubstituted imidazole derivatives using benzoin, an aromatic aldehyde, an aromatic amine in the presence of ammonium acetate catalyzed by hig...A simple, convenient and efficient method for the synthesis of 1,2,4,5-tetrasubstituted imidazole derivatives using benzoin, an aromatic aldehyde, an aromatic amine in the presence of ammonium acetate catalyzed by high surface area SiO2 and induced by free solar thermal energy was reported. C 2009 Kamal User Sadek. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
A bishydrazone formed by the condensation of isatinmonohydrazone and salicylaldehyde reacted with lanthanide(Ⅲ) chloride to form complexes of the type [Ln(HISA)2Cl3], where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(...A bishydrazone formed by the condensation of isatinmonohydrazone and salicylaldehyde reacted with lanthanide(Ⅲ) chloride to form complexes of the type [Ln(HISA)2Cl3], where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), or Gd(Ⅲ) and HISA= [(2-hydroxybenzaldehyde)-3-isatin]bishydrazone. Both reactions were carried out under microwave conditions. The ligand and the metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV visible, infrared, far infrared, and proton NMR spectral data. The ligand acted as neutral tridentate, coordinating through the carbonyl oxygen, azomethine nitrogen, and phenolic oxygen without deprotonation. The ligand and lanthanum(Ⅲ) complex were subjected to X-ray diffraction studies. The X-ray diffraction pattern of ligand exhibited its crystalline nature and that of the lanthanum(Ⅲ) complex indicated its amorphous character. The thermal decomposition behaviour of the complex, [La(HISA)2Cl3], was examined in the temperature range of 40-800 ℃ using TG, DTG, and DTA. The ligand and the metal complexes were screened for their antifungal activities.展开更多
In this article,plasma-assisted NH;synthesis directly from N;and H;over packing materials with different dielectric constants(BaTiO_(2),TiO_(2) and SiO_(2))and thermal conductivities(Be O,Al N and Al_(2)O_(2))at room ...In this article,plasma-assisted NH;synthesis directly from N;and H;over packing materials with different dielectric constants(BaTiO_(2),TiO_(2) and SiO_(2))and thermal conductivities(Be O,Al N and Al_(2)O_(2))at room temperature and atmospheric pressure is reported.The higher dielectric constant and thermal conductivity of packing material are found to be the key parameters in enhancing the NH;synthesis performance.The NH;concentration of 1344 ppm is achieved in the presence of BaTiO_(2),which is 106%higher than that of SiO_(2),at the specific input energy(SIE)of 5.4 k J·l^(-1).The presence of materials with higher dielectric constant,i.e.BaTiO_(2) and TiO_(2)in this work,would contribute to the increase of electron energy and energy injected to plasma,which is conductive to the generation of chemically active species by electron-impact reactions.Therefore,the employment of packing materials with higher dielectric constant has proved to be beneficial for NH;synthesis.Compared to that of Al_(2)O_(3),the presence of Be O and Al N yields 31.0%and 16.9%improvement in NH;concentration,respectively,at the SIE of5.4 k J·l^(-1).The results of IR imaging show that the addition of Be O decreases the surface temperature of the packed region by 20.5%to 70.3℃ and results in an extension of entropy increment compared to that of Al_(2)O_(3),at the SIE of 5.4 k J·l^(-1).The results indicate that the presence of materials with higher thermal conductivity is beneficial for NH;synthesis,which has been confirmed by the lower surface temperature and higher entropy increment of the packed region.In addition,when SIE is higher than the optimal value,further increasing SIE would lead to the decrease of energy efficiency,which would be related to the exacerbation in reverse reaction of NH;formation reactions.展开更多
The self-assembly of 1H-benzimidazole-5,6-dicarboxylic acid with barium chloride under hydrothermal conditions afforded a new 2D coordination polymer,[Ba2(L)(HL)Cl]n(1,L = 1H-benzimidazole-5,6-dicarboxylate),whi...The self-assembly of 1H-benzimidazole-5,6-dicarboxylic acid with barium chloride under hydrothermal conditions afforded a new 2D coordination polymer,[Ba2(L)(HL)Cl]n(1,L = 1H-benzimidazole-5,6-dicarboxylate),which was characterized by elemental analysis,infrared spectroscopy,thermogravimetric analysis,and single-crystal X-ray diffraction.Compound 1 is of monoclinic system,space group P21/c with a = 10.0145(6),b=25.6854(15),c=7.3116(4) ?,β = 99.4980(10)°,V = 1854.95(19)3,C18H9Ba2ClN4O8,Z = 4,Mr=719.42,Dc = 2.576 g/cm3,μ(MoKα) = 4.427 mm-1,F(000) = 1352,the final R = 0.0202 and wR=0.0465 for 3051 observed reflections with I 2σ(I).It exhibits an interesting two-dimensional network structure and high thermal stability(up to 420 ℃).展开更多
The title complex has been synthesized with 2,2'-biphenyl dicarboxylic acid and 1,10-phenanthroline(phen)in the solvent mixture of water and methanol.It crystallizes(C38H28CuN4O6,Mr = 700.1)in triclinic,space gro...The title complex has been synthesized with 2,2'-biphenyl dicarboxylic acid and 1,10-phenanthroline(phen)in the solvent mixture of water and methanol.It crystallizes(C38H28CuN4O6,Mr = 700.1)in triclinic,space group P1 with a = 1.0868(2),b = 1.2175(2),c = 1.6206(3)nm,α = 110.161(2),β = 102.605(3),γ = 93.667(2)o,V = 1941.6(6)nm3,Dc = 1.198 g/cm3,Z = 2,F(000)= 722,R = 0.0558 and wR = 0.1208.The crystal structure shows that the copper atom is coordinated with one oxygen atom from 2,2'-bphenyl dicarboxylic acid molecule and four nitrogen atoms from two 1,10-phenanthroline molecules,forming a distorted square-pyramidal coordination.The TG analysis shows that the title complex is stable under 160.0 ℃.展开更多
Niobium(V) ethoxide(Nb(OEt)5) was synthesized by electrochemical reaction of ethanol with niobium plate as the sacrificial anode,stainless steel as the cathode and tetraethylammonium chloride(TEAC) as the conductive a...Niobium(V) ethoxide(Nb(OEt)5) was synthesized by electrochemical reaction of ethanol with niobium plate as the sacrificial anode,stainless steel as the cathode and tetraethylammonium chloride(TEAC) as the conductive additive.The condensates were isolated by vacuum distillation under 5 kPa.The product was characterized by Fourier transform infrared(FT-IR) spectra,Raman spectra and nuclear magnetic resonance(NMR) spectra.The results indicate that the product is niobium ethoxide.Thermal properties of niobium ethoxide were analysed by TG/DTG.Vapour pressure was calculated from the Langmuir equation and the enthalpy of vaporization was calculated from the vapour pressure-temperature data using the Clausius-Clapeyron equation.The concentrations of impurity metallic elements in the sample were detected by ICP-MS.It is shown that the purity can reach 99.997%.The volatility and purity of the niobium ethoxide ensure that it could be a good precursor for chemical vapor deposition and atomic layer deposition of niobium oxide layers.展开更多
Perovskite-type La0.8Sr0.2MnO3 was prepared by stearic acid gel combustion method.The obtained powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scaning electron micro...Perovskite-type La0.8Sr0.2MnO3 was prepared by stearic acid gel combustion method.The obtained powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scaning electron micrograph(SEM)and X-ray photoelectron spectroscopy(XPS)techniques.The catalytic activity of La0.8Sr0.2MnO3 was investigated on thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)by thermal gravity-differential scanning calorimetry(TG-DSC)techniques.The experimental results show that La0.8Sr0.2MnO3 is an effective catalyst for HMX thermal decomposition.The surface-adsorbed species such as H2O,OH - and adsorbed oxygen(Oad)could result in an advance in the onset temperature of HMX thermal decomposition.The mixture system of Mn 3+ and Mn 4+ ions and lattice oxygen could play key roles for the increase of the decomposition heat of HMX because these exothermic reactions could be catalyzed by La0.8Sr0.2MnO3 between CO and NOx(from the thermal decomposition of HMX)and the oxidation reaction of CO.According to the previous researches and our results,perovskite-type La0.8Sr0.2MnO3 may be used as a novel catalyst or modifier for nitrate ester plasticized polyether(NEPE)propellant.展开更多
SiC/SiO2 nanochains were synthesized on a carbon fiber substrate by a catalyst-free thermal evaporation method in the Ar/CO atmosphere.X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FT-IR),scanning ele...SiC/SiO2 nanochains were synthesized on a carbon fiber substrate by a catalyst-free thermal evaporation method in the Ar/CO atmosphere.X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM)and transmission electron microscopy(TEM)revealed that the as-synthesized SiC/SiO2 nanochains are composed of single-crystalline SiC nanowires and amorphous SiO2 beads.The introduction of CO can promote the formation of SiO2,so that the SiC/SiO2 nanochains are subsequently formed during cooling.In addition,the photoluminescence spectrum of SiC/SiO2 nanochains showed a broad emission peak at around 350 nm,which is ascribed to the oxygen discrepancy in the SiO2 beads as well as the SiC/SiO2 interfacial effect.These findings can provide guidance for further study of the vapor growth of 1D SiC-based materials.展开更多
基金the NSFC(22075019)National Key R&D Program of China(2017YFB1104300)。
文摘Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly rely on traditional bottom-up method,which involves tedious steps,time-consuming treatments,or additional alkaline media,and is unfavorable for high-efficiency production.Herein,we present a facile,ultrafast and general avenue to synthesize transition metal hydroxides on carbon substrate within 13 s by Joule-heating method.With high reaction kinetics caused by the instantaneous high temperature,seven kinds of transition metal-layered hydroxides(TM-LDHs)are formed on carbon cloth.Therein,the fastest synthesis rate reaches~0.46 cm^(2)s^(-1).Density functional theory calculations further demonstrate the nucleation energy barriers and potential mechanism for the formation of metal-based hydroxides on carbon substrates.This efficient approach avoids the use of extra agents,multiple steps,and long production time and endows the LDHs@carbon cloth with outstanding flexibility and machinability,showing practical advantages in both common and micro-zinc ion-based energy storage devices.To prove its utility,as a cathode in rechargeable aqueous alkaline Zn(micro-)battery,the NiCo LDH@carbon cloth exhibits a high energy density,superior to most transition metal LDH materials reported so far.
文摘A novel phosphorus-nitrogen containing intumescent flame retardant (P-N IFR) was prepared via the reaction of dichlor-opentate with N-methylaniline. The structure of the product was confirmed by ^1H NMR, ^31p NMR, MS and IR. TGA analysis showed it has effective thermal stability.
基金Supported by the Hunan Provincial Department of Science and Technology Project (2009FJ3101)
文摘One novel binuclear copper(Ⅱ) complex [Cu 2 (Hpt) 2 (CO 3) 2 (H 2 O) 2 ]·H 2 O with copper carbonate and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) was hydrothermally synthesized and characterized by IR and X-ray diffraction analysis.The complex crystallizes in triclinic,space group P2 1 /n with a=0.6862(1),b=0.7805(1),c=1.1983(2) nm,α=72.03(2),β=107.72(3),γ=75.28(2)o,V=0.5884 nm 3,D c=2.105 g/cm 3,Z=1,F(000)=357,GOOF=1.041,the final R=0.01859 and wR=0.04348.The whole molecule is composed of two cooper ions,two Hpt molecules,two carbonate and three water molecules,forming a binuclear structure.The crystal structure shows that the cooper ion is coordinated with three nitrogen atoms from two Hpt molecules,two oxygen atoms from one carbonic acid and one water molecule,forming a distorted square pyramidal geometry.The TG analysis result shows that the title complex is stable under 131.0 ℃.
基金supported by the Youth Foundation of Luoyang Normal University(No.10000875)the Foundation of Education Department of Henan Province(No.2011A150021)
文摘A new 3d-4fheterometallic polymer {[Sm2Cu(PDC)2(SO4)2(H20)6]·2H2O}n 1 has been synthesized by Sm2O3, Cu(SO4)2·5H2O and pyridine-3,5-dicarboxylic acid under hydrothermal conditions. The compound crystallizes in triclinic system, space group Pi, with a = 6.352(7), b = 10.040(10), c = 10.315(11) A, α = 94.958(14), β = 95.556(7), γ = 99.747(14)°, V = 641.7(12)A3, Z = 1, M, = 1030.63, Dc= 2.651 Mg/m3,μ = 5.615 mm-1, F(000) = 491, the final R = 0.0491 and wR = 0.1345 for 2098 observed reflections with I 〉 2σ(I). The compound is a three-dimensional network structure in which infinite lanthanide-carboxylate chains are linked by [Cu($04)2]2- metalloligands to form a mixed-metal coordination network.
基金supported by the National Natural Science Foundation of China(No.21243007)National Defense Fundamental Scientific Research(No.B09201100051)
文摘A new energetic organic potassium salt bis(dinitromethyl)difurazanyl ether potas- sium salt [K2(BDFE)] was synthesized, and structurally characterized by elemental analysis, IR spectra, t3C NMR and single-crystal X-ray diffraction. K2(BDFE) crystallizes in monoclinic system, space group C2/c with a = 17.342(3), b = 12.6943(17), c = 8.0972(11) A, β = 110.630(2)°, V = 1668.3(4) A3, Z = 4, Dc = 2.000 g/cm3, F(000) = 1000,μ= 0.675 mm-1, S = 1.058, the final R = 0.0499 and wR = 0.1452. The K ion is eight-coordinated with eight O atoms from one water molecule and four bis(dinitromethyl)difurazanyl ethers (BDFE), forming a distorted dodecahedral structure. Thermal decomposition of the title complex was studied by using DSC and TG-DTG. There are primarily two exothermic decomposition processes between 200 and 370 ℃.
基金This work is sponsored by National Key Fundamental Research Development Plan ("973" Plan, No.2004CB217807)the China National Petroleum Corporation (No. B04A50502)
文摘The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate (CTriMATT) were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Ultraviolet visible (UV-Vis) spectra. The results showed that the as-synthesized CTriMATT had high purity and good crystallinity. The introduction of alkyl groups induced a shift of the stretching vibration band of W-S bond to lower wavenumber, while it had no influence on the position of WS4^2-. Thermogravimetric analysis (TG), differential thermal analysis (DTA) and in situ XRD characterizations revealed that CTriMATT began to decompose at 423 K in nitrogen and was converted to WS2 eventually. In addition, the decomposition product of CTriMATT at 673 K in nitrogen was characterized by N2 adsorption (BET) and scanning electron microscopy (SEM). The results demonstrated that WS2 with higher specific surface area, and pore volume could be obtained from the thermal decomposition of CTriMATT in nitrogen.
基金The project was supported by the National Natural Science Foundation of China (20471008) and the Fundamental Research Foundation of Beijing Institute of Technology (BIT-UBF-200302B01&BIT-UBF-200502B4221)
文摘A dinuclear complex Cd2(dnba)4(pyridine)4 (dnba = 3,5-dinitrobenzoate) has been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction, elemental analysis, FT-IR spectroscopy, DSC and TG-DTG techniques. The complex with empirical formula C48H32Cd2NI2024 (Mr = 692.83) crystallizes in monoclinic, space group P21/n with a - 12.0344(14), b = 10.5752(13), c = 21.578(3) A, β = 104.150(2)°, V = 2662.8(6) A^3, Z = 2, D, = 1.728 g/cm^3,μ(MoKa) = 0.897 mm^-1, F(000) = 1384, S = 1.016 and (△/σ)max = 0.001. R = 0.0638 and wR = 0.0737 for all data; the final R = 0.0337 and wR = 0.0644. In this complex, four carboxylates are bidentate-or chelate-coordinated with the Cd(Ⅱ) centers to give the dinuclear structure. The other coordination positions of Cd(Ⅱ) are occupied by the lone pair electrons from N of four pyridines. Thermal analyses DSC and TG-DTG have been used to determine the thermal decomposition mechanism of the title complex.
基金This work was supported by the Basic Research of Hunan Province (03JZY3036),Science Foundation of Hengyang Normal University of China (2006A15) and Foundation of the Eleventh Five-year Key Constructing Discipline of Hunan Province
文摘A novel manganese(Ⅱ) coordination polymer [Mn(L^1)2(H2O)]·2H2O (HL^1 = 2,6- dichlorobenzoic acid) 1 has been synthesized and structurally characterized. X-ray diffraction analyses reveal that 1 is a one-dimensional chain structure bridged by water molecules and 2,6- dichlorobenzoic acid. The crystal is of monoclinic, space group P21/c with α = 12.9701(19), b = 20.592(3), c = 7.3759(10) A, β = 102.660(2)°, V = 1.9221(5). nm^3, Z = 4, C14H12Cl4MnO7, Mr= 488.98, Dc= 1.690 g/cm^3, p = 1.275 mm^-1, F(000) = 980, Rint = 0.0348, R = 0.0350, and wR = 0.0755. In the crystal the manganese atom is six-coordinated by two oxygen atoms from water and four oxygen atoms from four 2,6-dichlorobenzolate molecules, completing an octahedral geometry.
基金Supported by the Natural Science Foundation of Hunan Province(No.11JJ9006)Key Project of Science and Technology Plan of Hunan Province(2012FJ2002)the Construct Program of the Key Discipline in Hunan Province
文摘A new complex has been synthesized with o-methylbenzoyl-benzoic acid(HL) and 1,10-phenanthroline(phen) in the mixture of water and ethanol. It crystallizes in monoclinic, space group C2/c with a = 13.6328(18), b = 17.7876(18), c = 19.998(2), β = 104.720(4)o, C54H48N4O11Zn, Mr = 994.33, V = 4690.2(9)3, Dc = 1.408 g/cm3, Z = 4, F(000) = 2072, μ(MoKα) = 0.59 mm-1, R = 0.0736 and wR = 0.2029. The crystal structure shows that the zinc ions are coordinated with two oxygen atoms from two HL molecules and four nitrogen atoms from two phen molecules, forming distorted octahedral coordination geometry. The fluorescent and thermal stability properties of the complex are studied. The result shows that it has one fluorescent emission band at around 412 nm. In addition, the complex is stable under 210 ℃.
文摘A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulation structure. How to use the general thermal response factors and z-transfer function coefficients toca1culate the indoor air temperature variation directly is also studied. It is shown through practical use that it iseasy to program with the methods presented in this paper and the calculated results are reliable.
文摘Application of the Semenov theory of spontaneous ignition to evaluation of the critical temperature (Tc) in thermal explosion (TE) synthesis was conducted with the Ti-75at pct Al binary system using nonisothermal differential scanning calorimetry (DSC) at different heating rates. And the critical temperature for isothermal TE is predicted to be 728.9癈 by the multiple linear regression of Tcs evaluated according to Semenov theory, which is close to the range of 740~745癈 obtained from the isothermal DSC observation. This result proves that Semenov theory of spontaneous ignition is also feasible for TE synthesis in binary metallic systems like Ti-75 at. pct Al system.
基金Supported by the National Natural Science Foundation of China(No. 20371013, 20421303),National Key Basic ResearchProgram of China(No. 2003CB615807) the State Key Laboratory Base of Novel Functional Materials and Preparation Science(Ningbo University).
文摘A natural mineral, lindgrenite Cu3 ( MoO4 )2 ( OH)2, was synthesized from a mixture of sodium molybdate, copper sulfate, and morpholine in water under autogenous pressure at 170 ℃. The crystal structure of the mineral was determined and the final refinement for 791 observed reflections with Ⅰ 〉 2σ(Ⅰ) gave R1 = 0. 0205 and wR2 = 0. 0496. The thermal stability of the mineral was investigated by using TG-DTA and variable-temperature in situ X-ray diffraction(XRD) techniques. The crystalline Cu3Mo2O9 was obtained when the mineral underwent thermal dehydration at a temperature ranging from 300 to 400 ℃, and the mixture of MoO3 and CuO was formed through decomposition of Cu3Mo2O9 at a temperature ranging from 650 to 700 ℃. Therefore, the structure of the mineral was thermally unstable at above 300 ℃, suggesting that Lindgrenite was likely formed via the hydrothermal route occurring in the nature.
文摘A simple, convenient and efficient method for the synthesis of 1,2,4,5-tetrasubstituted imidazole derivatives using benzoin, an aromatic aldehyde, an aromatic amine in the presence of ammonium acetate catalyzed by high surface area SiO2 and induced by free solar thermal energy was reported. C 2009 Kamal User Sadek. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘A bishydrazone formed by the condensation of isatinmonohydrazone and salicylaldehyde reacted with lanthanide(Ⅲ) chloride to form complexes of the type [Ln(HISA)2Cl3], where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), or Gd(Ⅲ) and HISA= [(2-hydroxybenzaldehyde)-3-isatin]bishydrazone. Both reactions were carried out under microwave conditions. The ligand and the metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV visible, infrared, far infrared, and proton NMR spectral data. The ligand acted as neutral tridentate, coordinating through the carbonyl oxygen, azomethine nitrogen, and phenolic oxygen without deprotonation. The ligand and lanthanum(Ⅲ) complex were subjected to X-ray diffraction studies. The X-ray diffraction pattern of ligand exhibited its crystalline nature and that of the lanthanum(Ⅲ) complex indicated its amorphous character. The thermal decomposition behaviour of the complex, [La(HISA)2Cl3], was examined in the temperature range of 40-800 ℃ using TG, DTG, and DTA. The ligand and the metal complexes were screened for their antifungal activities.
基金the financial support from National Natural Science Foundation of China(No.51976093)K C Wong Magna Fund in Ningbo University。
文摘In this article,plasma-assisted NH;synthesis directly from N;and H;over packing materials with different dielectric constants(BaTiO_(2),TiO_(2) and SiO_(2))and thermal conductivities(Be O,Al N and Al_(2)O_(2))at room temperature and atmospheric pressure is reported.The higher dielectric constant and thermal conductivity of packing material are found to be the key parameters in enhancing the NH;synthesis performance.The NH;concentration of 1344 ppm is achieved in the presence of BaTiO_(2),which is 106%higher than that of SiO_(2),at the specific input energy(SIE)of 5.4 k J·l^(-1).The presence of materials with higher dielectric constant,i.e.BaTiO_(2) and TiO_(2)in this work,would contribute to the increase of electron energy and energy injected to plasma,which is conductive to the generation of chemically active species by electron-impact reactions.Therefore,the employment of packing materials with higher dielectric constant has proved to be beneficial for NH;synthesis.Compared to that of Al_(2)O_(3),the presence of Be O and Al N yields 31.0%and 16.9%improvement in NH;concentration,respectively,at the SIE of5.4 k J·l^(-1).The results of IR imaging show that the addition of Be O decreases the surface temperature of the packed region by 20.5%to 70.3℃ and results in an extension of entropy increment compared to that of Al_(2)O_(3),at the SIE of 5.4 k J·l^(-1).The results indicate that the presence of materials with higher thermal conductivity is beneficial for NH;synthesis,which has been confirmed by the lower surface temperature and higher entropy increment of the packed region.In addition,when SIE is higher than the optimal value,further increasing SIE would lead to the decrease of energy efficiency,which would be related to the exacerbation in reverse reaction of NH;formation reactions.
文摘The self-assembly of 1H-benzimidazole-5,6-dicarboxylic acid with barium chloride under hydrothermal conditions afforded a new 2D coordination polymer,[Ba2(L)(HL)Cl]n(1,L = 1H-benzimidazole-5,6-dicarboxylate),which was characterized by elemental analysis,infrared spectroscopy,thermogravimetric analysis,and single-crystal X-ray diffraction.Compound 1 is of monoclinic system,space group P21/c with a = 10.0145(6),b=25.6854(15),c=7.3116(4) ?,β = 99.4980(10)°,V = 1854.95(19)3,C18H9Ba2ClN4O8,Z = 4,Mr=719.42,Dc = 2.576 g/cm3,μ(MoKα) = 4.427 mm-1,F(000) = 1352,the final R = 0.0202 and wR=0.0465 for 3051 observed reflections with I 2σ(I).It exhibits an interesting two-dimensional network structure and high thermal stability(up to 420 ℃).
基金Supported by the Natural Science Foundation of Hunan Province (No.11JJ9006)Science and Technology Committee of Hunan Province (2009FJ3101)Science and Technology Committee of Hengyang (2011kj25)
文摘The title complex has been synthesized with 2,2'-biphenyl dicarboxylic acid and 1,10-phenanthroline(phen)in the solvent mixture of water and methanol.It crystallizes(C38H28CuN4O6,Mr = 700.1)in triclinic,space group P1 with a = 1.0868(2),b = 1.2175(2),c = 1.6206(3)nm,α = 110.161(2),β = 102.605(3),γ = 93.667(2)o,V = 1941.6(6)nm3,Dc = 1.198 g/cm3,Z = 2,F(000)= 722,R = 0.0558 and wR = 0.1208.The crystal structure shows that the copper atom is coordinated with one oxygen atom from 2,2'-bphenyl dicarboxylic acid molecule and four nitrogen atoms from two 1,10-phenanthroline molecules,forming a distorted square-pyramidal coordination.The TG analysis shows that the title complex is stable under 160.0 ℃.
基金Project(2007AA03Z425) supported by the National Hi-tech Research and Development Program of ChinaProject(50404011) supported by the National Natural Science Foundation of China
文摘Niobium(V) ethoxide(Nb(OEt)5) was synthesized by electrochemical reaction of ethanol with niobium plate as the sacrificial anode,stainless steel as the cathode and tetraethylammonium chloride(TEAC) as the conductive additive.The condensates were isolated by vacuum distillation under 5 kPa.The product was characterized by Fourier transform infrared(FT-IR) spectra,Raman spectra and nuclear magnetic resonance(NMR) spectra.The results indicate that the product is niobium ethoxide.Thermal properties of niobium ethoxide were analysed by TG/DTG.Vapour pressure was calculated from the Langmuir equation and the enthalpy of vaporization was calculated from the vapour pressure-temperature data using the Clausius-Clapeyron equation.The concentrations of impurity metallic elements in the sample were detected by ICP-MS.It is shown that the purity can reach 99.997%.The volatility and purity of the niobium ethoxide ensure that it could be a good precursor for chemical vapor deposition and atomic layer deposition of niobium oxide layers.
基金Supported by the National Natural Science Foundation of China (20671084)
文摘Perovskite-type La0.8Sr0.2MnO3 was prepared by stearic acid gel combustion method.The obtained powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scaning electron micrograph(SEM)and X-ray photoelectron spectroscopy(XPS)techniques.The catalytic activity of La0.8Sr0.2MnO3 was investigated on thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)by thermal gravity-differential scanning calorimetry(TG-DSC)techniques.The experimental results show that La0.8Sr0.2MnO3 is an effective catalyst for HMX thermal decomposition.The surface-adsorbed species such as H2O,OH - and adsorbed oxygen(Oad)could result in an advance in the onset temperature of HMX thermal decomposition.The mixture system of Mn 3+ and Mn 4+ ions and lattice oxygen could play key roles for the increase of the decomposition heat of HMX because these exothermic reactions could be catalyzed by La0.8Sr0.2MnO3 between CO and NOx(from the thermal decomposition of HMX)and the oxidation reaction of CO.According to the previous researches and our results,perovskite-type La0.8Sr0.2MnO3 may be used as a novel catalyst or modifier for nitrate ester plasticized polyether(NEPE)propellant.
基金Project(U19A2088)supported by the National Natural Science Foundation of ChinaProject(2019RS2058)supported by the Special Fund for Innovative Construction of Hunan Province,China。
文摘SiC/SiO2 nanochains were synthesized on a carbon fiber substrate by a catalyst-free thermal evaporation method in the Ar/CO atmosphere.X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM)and transmission electron microscopy(TEM)revealed that the as-synthesized SiC/SiO2 nanochains are composed of single-crystalline SiC nanowires and amorphous SiO2 beads.The introduction of CO can promote the formation of SiO2,so that the SiC/SiO2 nanochains are subsequently formed during cooling.In addition,the photoluminescence spectrum of SiC/SiO2 nanochains showed a broad emission peak at around 350 nm,which is ascribed to the oxygen discrepancy in the SiO2 beads as well as the SiC/SiO2 interfacial effect.These findings can provide guidance for further study of the vapor growth of 1D SiC-based materials.