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101.
Two-loop contributions to Majorana mass and transition magnetic moment in a gauge model not in conflict with decaying neutrino
dark matter (DDM) hypothesis have been studied. Another variant of an earlier model [J Dhar and S Dev,Pramana — J. Phys.
39 541 (1992)] consistent with the DDM hypothesis is proposed and is shown to lead to large enough neutrino magnetic moment
and consistent with the phenomenological constraints on neutrino mass. 相似文献
102.
Umesh Gaur Miao -Yong Cao R. Pan B. Wunderlich 《Journal of Thermal Analysis and Calorimetry》1986,31(2):421-445
It is shown that heat capacities of linear macromolecules consisting of all-carbon single-bonded backbones can be calculated from the appropriate contributions of substituted carbon atoms to a precision of about – 0.2±2.5% (155 data points), which is similar to the experimental precision. Heat capacity contributions of 42 groups are given over the full range of measurement and reasonable extrapolation. The quality of the addition scheme is tested on 16 series of measurements on homopolymers, copolymers and blends. The addition scheme works for all these different states of aggregation of the constituent groups. The basis of the addition scheme is discussed.
On leave from the University of Science and Technology of China, Hefei, Peoples Republic of China.
This work was supported through the many years it took to assemble the needed experimental data by the National Science Foundation,-Polymers Program, Grant # DMR 8317097. 相似文献
Zusammenfassung Es wird gezeigt, daß Wärmekapazitäten von aus Hauptketten mit ausschließlich C-C-Einfachbindungen bestehenden Makromolekülen aus geeigneten Beiträgen der substituierten Kohlenstoffatome mit einer Genauigkeit bis etwa –0.2±2.5% (155 Datenpunkte) berechnet werden können, was der experimentellen Genauigkeit nahe kommt. Wärmekapazitätsbeiträge von 42 Gruppen wurden über den vollen Meßbereich hinweg und durch sinnvolle Extrapolation bestimmt und angegeben. Die Zuverlässigkeit des Additionsschemas wurde in 16 Meßreihen an Homopolymeren, Kopolymeren und Mischungen getestet. Das Additionsschema ist für alle diese verschiedenen Anordnungen der konstitutionellen Gruppen zutreffend. Die Grundlagen des Additionsschemas werden diskutiert.
, , , , , –0,2 ±2,5% (155 ), . 42 - . 16 , . . .
On leave from the University of Science and Technology of China, Hefei, Peoples Republic of China.
This work was supported through the many years it took to assemble the needed experimental data by the National Science Foundation,-Polymers Program, Grant # DMR 8317097. 相似文献
103.
Nag Purnima Chaturvedi Alok Tripathi Umesh N. Bohra Rakesh Srivastava Ghanshyam Mehrotra Ram C. Wang H.Q. 《Transition Metal Chemistry》2002,27(6):651-655
Silver(I) dialkyl/alkylene dithiophosphates of the types [Ag{S2P(OR)2}] and [Ag{S2P(OGO)}] (where R = –Pr
n
; G = –CMe2CH2CHMe–, –CH2CMe2CH2–, –CMe2CMe2– or –CH2CH2CHMe–) have been prepared by treating an aqueous solution of AgNO3 with ammonia salts of the respective dithiophosphoric acid. The derivatives form 1:1 adducts readily with 2,2-bipyridine or Ph3P in CH2Cl2 solution. These novel complexes have been characterized by elemental analyses, molecular weight measurements and spectral (i.r., 1H- and 31P-n.m.r.) studies. The crystal structure of [Ag{S2POCH2CMe2CH2O · PPh3]2 · 2H2O exhibits an unsymmetrical attachment of the silver(I) to the ligand moiety. 相似文献
104.
The heat capacities of SnSe and SnSe2 were measured in the temperature range 230–580 K using a computer interfaced differential scanning calorimeter. From these measurements, the Debye temperatures of SnSe and SnSe2 were calculated as a function of temperature. An estimated Debye temperature of 220 K for SnSe was used to calculate the absolute entropy of SnSe at 298 K to be 85.2 ± 6.0 J K?1 mole?1. In the light of other work, the suitability of Debye temperatures for estimating low temperature heat capacities of SnSe2 is questioned. 相似文献
105.
[reaction: see text]. Radicals derived from the phosphorus reagents, ethylpiperidine hypophosphite (EPHP) and diethylphosphine oxide (DEPO), are used in two related approaches to synthesis of the alkaloid horsfiline (1). In particular, DEPO proves beneficial for effecting cyclizations at 80 degrees C that are difficult or impossible with Bu(3)SnH. 相似文献
106.
Milind Kondalkar Umesh Fegade Sopan Ingle 《Journal of Dispersion Science and Technology》2018,39(11):1635-1643
Recently composite metal oxides have gained significant attention to be used as adsorbent because of their synergetic effects. Particularly Manganese containing composite oxides are useful for removal of inorganic oxyacids such as phosphate or arsenate. In present study fabrication of Mn-Zn-Ti Oxide adsorbent for phosphate removal carried out via co precipitation method. Surface properties deduced by TEM, FESEM, EDAX and XRD, revealed nanosized composite material has a porous nature constitute of alloy type mixing of the metals. Size of the nanocomposite found to be as small as 6?nm. Adsorption capacity for phosphate estimated at different pH, time and adsorbent dose by batch mode. In addition desorption properties and thermodynamic study also carried out. Several isotherms and kinetic models applied to observe adsorption properties of the Mn-Zn-Ti Oxide nanocomposite. Adsorption capacity found to be 151?mg/g at pH 6, time 90?min, adsorbent dose 0.20?g/L and phosphate concentration of 200?mg/L. Adsorption data fitted to second order kinetics and Freundlich isotherm. Formation of complex between nanocomposite and phosphate predicted from FTIR and supported by pH kinetic and isotherm studies. Desorption and reusability found to be well maintained over five cycles. 相似文献
107.
108.
Anil D. Naik Satish M. Annigeri Umesh B. Gangadharmath Vidyanand K. Revankar Vinayak B. Mahale 《Journal of Molecular Structure》2002,616(1-3):119-127
2,6-Diformyl-p-cresol serves as a starting point for the generation of multidentate N/O/S chelating agents. Condensation with 4-(X-phenyl) thiosemicarbazide yields the pentadentate ligand having SNONS donor sequences, capable of holding two metal ions in close proximity. The ligands behave as mono/di/tri basic depending on the pH of the medium. Stereochemical diversity in the reaction product of such ligands with nickel(II) chloride at different pH is observed. Sterically demanding substituted ligands in association with various exogenous bridges dictate the geometry and coordination number of such complexes. The compounds were investigated by elemental analysis, molar conductivities, electronic spectra, IR, NMR, FAB mass spectra, TG-DTG, magnetic susceptibility measurements. Varieties of geometries such as square planar, square pyramidal, octahedral and square planar–square pyramidal are observed. Cryomagnetic data for the complexes (79–296 K) can be reproduced by an equation based on the Heisenberg model (H=−2JS1S2, S1=S2=1). The singlet–triplet splitting, J varies systematically with the coordination geometry about the Ni2(SNONS) core, with the hydroxo bridged complex exhibiting the greatest degree of antiferromagnetic coupling. The coupling is somewhat weaker for the chloro-bridged complexes. None of the complexes have shown any appreciable antimicrobial activity. 相似文献
109.
110.