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1.
Results of thermochemical studies of a new compound, potassium morpholinodithiocarbamate, are presented. The enthalpies of its solution in water at various dilutions and the specific heat at 173–348 K were examined by the experimental methods of isothermal and dynamic calorimetry.  相似文献   
2.
Ferrites with the composition GdMIIFe2O5.5 (MII = Mg, Ca, Sr) were synthesized from the corresponding oxides by the solid-phase method. The temperature dependence of the specific heat was studied by dynamic calorimetry in the temperature range 298.15 673 K. Equations describing this temperature dependence were derived. The temperature dependences of the thermodynamic functions were calculated.  相似文献   
3.
The results are given of the synthesis and a comparative study of the toxicities of some phosphorylated derivatives of the alkaloids l-ephedrine and d-pseudoephedrine. It has been shown that the introduction of phosphorus- and sulfur-containing fragments considerably lowers the toxicity of the alkaloids. Institute of Organic Synthesis and Coal Chemistry, National Academy of Sciences of the Republic of Kazakhstan, Karaganda. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 406–408, May–June, 1994.  相似文献   
4.
-(Thiocarbamoylthio)propionic acids derived from alkaloids, morpholine, and piperidine and their esters, amides, and nitriles were prepared by reactions of the corresponding dithiocarbamic acids with acrylic acid and its derivatives. Some of the compounds were tested for insecticidal activity.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 8, 2004, pp. 1336–1339.Original Russian Text Copyright © 2004 by Zhivotova, Gazaliev, Ibraev, Fazylov, Kasenov.  相似文献   
5.
Heat of solution of salsoline salsolinodithiocarbamate (SS) at 1 : 18 000, 1 : 36 000, and 1 : 72 000 dilution (mol per mol H2O) was determined on a DAK-I-IA calorimeter, and the standard heat of solution at infinite dilution was estimated. The temperature dependence of the heat capacity of SS was studied over the range 173–348 K. The heats of combustion and fusion, and the standard heat of formation of liquid (molten) and crystalline SS were estimated by indirect methods.  相似文献   
6.
Russian Journal of Physical Chemistry A - The temperature dependences of the specific heat capacities of nanosized samples of lanthanum magnesium cobaltite cuprate manganite LaMgCoCuMnO6 and...  相似文献   
7.
The heat capacities of nanosized ferro-chromo-manganites LaM0.5 IIFeCrMnO6.5 (MII–Mg, Ca, Sr, Ba) are measured via dynamic calorimetry in the temperature range of 298.15–673 K using an IT-S-400 instrument. It is established that the C°p~f(T) function of LaM0.5 IIFeCrMnO6.5 (MII–Mg, Ca, Sr, Ba) has λ-type effects, due probably to phase transitions of the second order. Considering the temperatures of the phase transitions, equations of the heat capacity of ferro-chromo-manganites LaM0.5 IIFeCrMnO6.5 (MII–Mg, Ca, Sr, Ba) as a function of temperature are derived on the basis of experimental data. Thermodynamic functions Н°(Т)–Н°(298.15), S°(Т), and Ф хх(Т) are calculated in the temperature range of 298.15–675 K.  相似文献   
8.
The enthalpies of solution of cytisine derivatives (phosphoric acid cytiside dimethyl ester, cytisinovinyloxyethylaminothiourea) in 96% ethanol at various dilutions were determined by isothermal calorimetry. Equations describing the dependences ΔH s 0 = f(m 1/2) (m is the molal concentration) were obtained. The standard enthalpies of solution, combustion, melting, and formation (at 298.15 K) of the compounds were calculated.  相似文献   
9.
Calorimetric methods were used to study the enthalpy of solution of the alkaloids glaucine C21H25NO4 and lappaconitine C32H44N2O8 in 96% ethanol and their heat capacity in the temperature ranges 173–298.15 and 173–423 K. Equations describing the dependences ΔH sol m f( $\sqrt m $ ) (m is molal concentration) and C p 0 f( $\sqrt T $ ) for the compounds under study were derived. The enthalpies of combustion, melting, and formation of C21H25NO4 and C32H44N2O8 were estimated by means of theoretical calculations.  相似文献   
10.
Ferrites LaNaMnFeO5 and LaKMnFeO5 have been synthesized by the ceramic method from lanthanum(III) and iron(III) oxides and sodium and potassium carbonates. The ferrites crystallize in the orthorhombic crystal system with the following lattice parameters: LaNaMnFeO5: a = 10.943 ± 0.002 Å, b = 11.022 ± 0.001 Å, c = 16.165 ± 0.028 Å, V 0 = 1949.72 Å3, Z = 16, V unit cell 0 = 12.1.85 Å3, ρX = 4.83, ρpycn = 4.76 ± 0.09 g/cm3; LaKMnFeO5: a = 10.959 ± 0.011 Å, b = 11.036 ± 0.005 Å, c = 17.825 ± 0.074 Å, V 0 = 2155.81 Å3, Z = 16, V unit cell 0 = 134.74 Å3, ρX = 4.54, ρpycn = 4.46 ± 0.07 g/cm3.  相似文献   
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