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121.
V. Kumar Murty 《Compositio Mathematica》2001,127(3):273-288
Stark conjectured that given a positive integer h, there are only a finite number of CM-fields L with class number equal to h. We prove this conjecture for fields L of degree 6 whose normal closure is solvable. 相似文献
122.
V.M. Soundalgekar T.V. Ramana Murty N.V. Vighnesam 《International Journal of Heat and Fluid Flow》1984,5(1):54-56
Effects of buoyancy forces on forced and free convective flow of water at 4°C past a semi-infinite vertical plate at constant temperature are studied. Flow is assumed to be vertically upwards. Similarity solutions are derived and the resulting equations are solved numerically on a computer. Velocity and temperature profiles are shown graphically and numerical values of the skin friction and the rate of heat transfer are entered in tables. It is observed that the skin friction and the Nusselt number increase with increasing Gr/Re2, where Gr is the Grashof number and Re is the Reynolds number 相似文献
123.
Let f be a cuspidal normalized eigenform of weight ≥ 2 for Г0(N),with Fourier expansion $f(z) = \sum\limits_{n = 1}^\infty {a_f (n)e^{2\pi inz} } $ While the Galois representations associated to f can be used effectively to study the divisibility properties of the Fourier coefficients, it is very difficult to analyze the condition a f (p) = 0 (mod p). In this paper, we show that the problem is accessible in the case that f has complex multiplication. Under some mild conditions on f, we show that for p sufficiently large, a f (p) = 0 (mod p) in fact implies that a f (p) = 0. 相似文献
124.
M. S. R. Murty Mohana Rao Katiki B. Ramalingeswara Rao Jagadeesh Babu Nanubolu Sudheer Kumar Buddana R. S. Prakasham 《合成通讯》2014,44(18):2724-2737
An efficient, green, and chemoselective S-alkylation of 5-aryl-1H-1,2,4-triazole-3-thiones with diethyl (3-bromopropyl)phosphonate in water, catalyzed by nano-Fe2O3 under ligand- and base-free conditions, is reported. Clean reaction, less expensive catalyst, excellent yields, and easy workup are the advantages of the present method. The catalyst can be easily collected by a magnet and recycled without significant loss in catalytic activity. The newly synthesized compounds were screened for their antioxidant property by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay. The majority of the compounds exhibited good antioxidant activity. 相似文献
125.
Biswanath Das Avula Satyakumar Bommena Ravikanth Bommena Vittal Rao Tuniki Venugopal Raju Busi Siddhardha Upadyayula Suryanaryana Murty 《Journal of heterocyclic chemistry》2013,50(2):430-434
A novel pentacyclic heterocycle has been synthesized starting from D ‐glucose involving two crucial conversions: the intramolecular cycloaddition of O‐allyloxy furanaldoxime derived from D ‐glucose to furanopyran‐2‐isoxazoline and its diastereoselective reductive cleavage to the corresponding cis‐1,3‐amino alcohol. The antibacterial and antifungal activities of the synthesized heterocycle have been examined. 相似文献
126.
Amorphous structure generated by mechanical alloying (MA) is often used as a precursor for generating nanocomposites through
controlled devitrification. The amorphous forming composition range of ternary Al-Ni-Ti system was calculated using the extended
Miedema’s semi-empirical model. Eleven compositions of this system showing a wide range of negative enthalpy of mixing (−ΔH
mix) and amorphization (−ΔH
amor) of the constituent elements were selected for synthesis by MA. The Al88Ni6Ti6 alloy with relatively small negative ΔH
mix (−0.4 kJ/mol) and ΔHamor (−14.8 kJ/mol) became completely amorphous after 120 h of milling, which is possibly the first report of complete amorphization
of an Al-based rare earth element free Al-TM-TM system (TM = transition metal) by MA. The alloys of other compositions selected
had much more negative ΔHmix and Hamor; but they yielded either nanocomposites of partial amorphous and crystalline structure or no amorphous phase at all in the
as-milled condition, evidencing a high degree of stability of the intermetallic phases under the MA environment. Hence, the
negative ΔH
mix and ΔH
amor are not so reliable for predicting the amorphization in the present system by MA 相似文献
127.
In this paper we discuss the aberration properties and design procedure of in-plane Ebert spectrograph using conventional
as well as holographic diffraction gratings. In both cases the gratings are situated at the well-known √3-position so that
the spectrum can be recorded on a flat surface. It has been found that the holographic grating system has better resolution
than the conventional grating system. The design parameters of a medium sized holographic grating spectrograph in which a
concave spherical mirror is mounted in the off-axis configuration have been specified. The performance of the spectrograph
has been evaluated by plotting spot diagram. 相似文献
128.
A.S.R. Anjeneyulu L.Ramachandra Row C. Subrahmanyam K.Suryanarayana Murty 《Tetrahedron》1973,29(23):3909-3914
From the leaves and stems of Euphorbia nerifolia Linn., a new triterpene was isolated besides friedelan-3α- andβ-ols, and taraxerol. From a study of its chemical reactions and spectral data, the new triterpene was shown to be glut-5(10)-en-1-one(3). 相似文献
129.
130.
Katta G. Murty 《Mathematical Programming》1980,19(1):213-219
We establish that in the worst case, the computational effort required for solving a parametric linear program is not bounded above by a polynomial in the size of the problem.This research is partially supported by Air Force Office of Scientific Research, Air Force Number AFOSR-78-3646. 相似文献