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1.
Journal of Thermal Analysis and Calorimetry - In recent decades, the growth of heat transfer using nanomaterials in the conventional base fluid has caught the attention of researchers...  相似文献   
2.
The synthesis has been effected of alkyl anabasinoprop-2-yl and alkyl piperidinoprop-2-yl methylphosphonothionates. It has been shown by1H,13C and31P NMR spectroscopies that the anabasine derivatives exist in solution as four diastereomeric forms. The kinetics of the interaction of the compounds synthesized with two types of cholinesterases has been studied.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, Fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 70–74, January–February, 1994.  相似文献   
3.
In quasi-steady operation, convection currents in a Bridgmandevice, used for producing a semi-conductor crystal, createinhomogeneities that may make the crystal unusable. It has oftenbeen suggested that additional forces due to rotation or magnetismmight be efficacious in reducing the segregation of the elementsof the alloy. It has been found that, over a wide range of rotationrates, there is no improvement in performance due to rotationabout the vertical axis. However, numerical results that havebeen obtained previously (Lee & Pearlstein, J. Crys. Growth240, 2002) indicate that, when effects of centrifugal buoyancyare introduced, a substantial reduction in segregation is achieved.In the work reported here, by contrast, in which we extend previouslarge-Rayleigh-number asymptotic analysis to include centrifugalbuoyancy, we find no improvement in radial segregation, butrather increasing segregation with increasing rotation rate.  相似文献   
4.
    
The selective dehydrogenation of the eudesmanolide -santonin and its alkylation with the introduction of an allyl fragment into its -lactone ring are described. It has been established that these reactions are regio- and stereo-selective. The structures of the compounds obtained were determined from their IR, UV, PMR, and mass spectra.Institute of Organic Synthesis and Coal Chemistry, Kazakhstan Academy of Sciences, Karaganda. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 518–522, September–October, 1992.  相似文献   
5.
Conclusions Some esters of O-alkyl methylphosphonic acid and thioesters of O-alkyl methylthiophosphonic acid derived from the alkaloids lupinine and epilupinine have been prepared. These were found to be reversible competitive inhibitors of acetylcholinesterase and butyrylcholinesterase.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 650–654, March, 1987.  相似文献   
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The effects of high-voltage pulsed discharge (HVPD) activation on the Raman spectra of saturated aqueous solutions of lithium sulfate (Li2SO4/H2O) in the range of the ν1(A) totally symmetric vibrations of the SO 4 2? anion and on the spectra of potassium thiocyanate KSCN/H2O in the region of the ν1(C≡N) vibrations of the SCN? anion have been studied. The temperature dependences of the width and frequency of the corresponding spectral lines have been investigated.  相似文献   
8.
Russian Journal of Electrochemistry - By methods of cyclic voltammetry and preparative electrolysis, the electrochemical properties of sterically hindered imidazolium salt...  相似文献   
9.
Russian Journal of Electrochemistry - Composite solid electrolytes are synthesized on the basis of the eutectic nitrate mixture of 0.42LiNO3–0.58KNO3 doped by aluminum oxide nanosized powder....  相似文献   
10.
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