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1.
The complexes [Ln(pic)3(DTSO)3] (Ln=La, Lu and Y; pic=picrate; DTSO=1,3-dithiane-1-oxide) were synthesized and characterized. Indirect structural determination by far infrared spectroscopy is presented. Results from thermal decomposition of these complexes by TG/DTG and DSC techniques are reported. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
2.
DSC, TG and quadrupole mass spectrometer data concerning methylquinuclidinium iodide (MeQ1), dried precursor gel, and crystalline levyne-type zeolite are discussed together with the thermal degradation of MeQ1 mixed with single inorganic components of the gel. It is shown that MeQ+ions play a role in the organization of the gel structure. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
3.
The investigation of europium(III) sulphate hydrate and samarium(III) sulphate hydrate was performed by thermal analysis (TG-DTG) and simultaneous infrared evolved gas analysis-Fourier transformed infrared (EGA-FTIR) spectroscopy. The TG, DTG and DTA curves were recorded at the 25–1400 °C in the dynamic air atmosphere by TG/DTA analyser. The infrared evolved gas analysis was obtained on the FTIR spectrometer. Eu2(SO4)3·nH2O (n = 3.97) and Sm2(SO4)3·nH2O (n = 8.11) were analysed, the dehydration and decomposition steps were investigated and the water content was calculated. The formation of different oxysulphates was studied.

The trace rare earth elements in Eu and Sm sulphates were determined by ICP-MS. The concentration of trace Eu, Sm, La, Gd, Y and Ce ranged from 3.9 × 10−6 to 1.5 × 10−4% (m/m).  相似文献   

4.
钱斌  孙尧俊  龙英才 《化学学报》2001,59(2):235-240
运用热分析技术,研究吸附在体相和表面结构完美的单晶状疏水全硅FER沸石孔道中的有机化合物的脱附行为,测定亲和性指数AT值和负载量。所研究的吸附质为直链烷烃、直链烷基醇、直链烷基胺等,结果显示醇有较低的AT值,而直链烷烃有较高的AT值,胺类有最高的AT值。证明全硅FER沸石骨架对烷基、胺基呈现出强的"亲和性",而对羟基呈现出“憎性”。同时还发现吸附质的链长对脱附性质、AT值也有较大影响。  相似文献   
5.
Polyacetylene films irradiated by-rays up to 100 MRad were studied by means of TMA, DTG and DSC methods.It is shown that as the irradiation dose increases the concentration of topological branching knots into the polymer chains and theT g values decrease, the total mass loss and the enthalpy of the thermal isomerization reaction also decrease.  相似文献   
6.
A set of seven bituminous coal chars has been characterised by IR spectroscopy (FTIR), thermogravimetry (TG) and elemental analysis. FTIR study provided suitable information to establish differences between coal samples according to their chemical compositions. The reactivity of these samples was also studied and correlated with the coal parameters of mean vitrinite reflectance, fuel ratio and H/C ratio. The data suggest that reactivity as determined can be correlated with the mean vitrinite reflectance, fuel ratio and H/C ratio (0.90). The order of reactivity of samples were; Amasra (S1) (R m= 0.65)>Azdavay (S4) (R m=0.99)»Armutcuk (S2) (R m=0.81)»Acenta (S3) (R m=0.92)>Ac2l2k (S6) (R m=1.11) Cay (S5) (R m=1.03)>Sogutozu (S7) (R m=2.14).  相似文献   
7.
DTA/TG and TG/DTG thermal studies and XRD investigations were carried out on pastes of lime-pozzolan binders to examine the relative hydration process. The binders were prepared with two natural pozzolans and hydrated lime, mixed together in different proportions. The main hydrated phases formed in the pastes are calcium silicate hydrate (CSH) and mono-carboaluminate. The growth of CSH was greater for the paste of the pozzolan richer in reactive constituents. For pastes with a higher lime/pozzolan ratio, a slowing of the formation of CSH was observed, while the formation of monocarboaluminate was more intense. The calcium hydroxide contents of the pastes obtained by thermogravimetric analysis made it possible to determine the pozzolanic activities of the two pozzolans under examination. The mortars for the various lime-pozzolan binders displayed characteristic hardening. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
8.
ZnSn(OH)6的热分解动力学   总被引:1,自引:0,他引:1  
用TG/DTG联用技术, 在2.5、5.0、10.0、15.0、20.0 K·min-1不同线性升温条件下, 研究了ZnSn(OH)6的热分解过程. 结果表明, 在氮气气氛下, ZnSn(OH)6在298-873 K范围内发生了一步分解. 其失重率与理论计算值相符. 应用非等温多重扫描速率法对热分解过程进行了动力学分析, ZnSn(OH)6在氮气中分解的活化能E=128.77 kJ·mol-1, 指前因子lg(A/s-1)=10.61, 机理函数为Mample单行法则.  相似文献   
9.
Thermal decomposition of mixed ligand thymine (2,4-dihydroxy-5-methylpyrimidine) complexes of divalent Ni(II) with aspartate, glutamate and ADA (N-2-acetamido)iminodiacetate dianions was monitored by TG, DTG and DTA analysis in static atmosphere of air. The decomposition course and steps of complexes [Ni(C5H6N2O2)(C4H5NO4)2−(H2O)2]·H2O, [Ni(C5H6N2O2)(C5H7NO4)2−(H2O)2]·H2O and [Ni(C5H6N2O2)(C6H8N2O5)2−(H2O)2]·1.5H2O were analyzed. The final decomposition products are found to be the corresponding metal oxides. The kinetic parameters namely, activation energy (E*), enthalpy (ΔH*), entropy (ΔS*) and free energy change of decomposition (ΔG*) are calculated from the TG curves using Coats–Redfern and Horowitz–Metzger equations. The stability order found for these complexes follows the trend aspartate > ADA > glutamate.  相似文献   
10.
The reactions of transition metal salts with taurine 5‐chlorosalicylaldelyde Schiff base gave two complexes [Ni(TCSSB)(H2O)3].H2O (1) and [Cu(TCSSB)(H2O)2]2[Cu(TCSSB)2].6H2O (2) (TCSSB=taurine‐5‐chlorosalicylaldelyde Schiff base), which were characterized by elemental analysis and X‐ray diffraction analysis. The complex 1 crystallized in monoclinic system with space group P2 1/c, and a=1.4816(2) nm, b=1.3953(2) nm, c= 0.7466(1) nm, β= 100.499(3)°, V=1.5176(4) nm3, Z=4, and an infinite 3‐D network structure was formed by hydrogen bonds among sulfo group, crystal water and coordinated water. Complex 2 crystallized in triclinic system with space group P1 , with the cell parameters: a = 0.6413(2) nm, b= 1.4596(3) nm, c= 1.6188(4) nm, a= 102.473(5)°, β= 98.979(4)°, γ=101.739°, V=1.4165(6) nm3, Z=1. The coordination environment between Cu(1) and Cu(2) is different. Cu(1) is slightly distorted square pyramidal while Cu(2) is distorted square‐plane. The complex 1 is mononuclear while the complex 2 is made up of two coordinated subunits, namely [Cu(TCSSB)2] and [CU(TCSSB)(H2O)2]2. Besides that the TG‐DTG of the complex 1 was analyzed, the thermal decomposition reaction of the complex was studied under a non‐isothermal condition by TG‐DTG. The TG and DTG curves indicate that the complex was decomposed in three stages: .  相似文献   
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