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排序方式: 共有190条查询结果,搜索用时 890 毫秒
101.
We analyse different error propagation mechanisms for conservativeand nonconservative time-integrators of nonlinear Schrödingerequations. We use a geometric approach based on interpretingwaves as relative equilibria. 相似文献
102.
103.
The thermal stability of linear low density polyethylene (LLDPE)/ethylene methyl acrylate (EMA) blends was studied using thermogravimetry.
The blend ratio as well as the presence of compatibilizer has significant effect on thermal stability of the blends. The compatibilization
of the blends using LLDPE-g-MA has increased the degradation temperature. Phase morphology was found to be one of the most
decisive factors that affected the thermal stability of both uncompatibilized and compatibilized blends. Dynamic mechanical
behavior of the blend was studied by dynamic mechanical analysis. The storage modulus of the blends decreased with increase
in EMA content. When compatibilized with LLDPE-g-MA the storage modulus of the blend increases. LLDPE-g-MA is an effective
compatibilizer as it increases the thermal stability and modulus of the blend. 相似文献
104.
In this paper, we study a holographic dark energy model with time varying gravitational constant G as well as holographic parameter c 2 in flat FRW space-time geometry. We obtain the evolution of equation of state parameter and the exact differential equation, which determine the evolution of the dark energy density based on varying G and c 2 parameter. Also, we determine the deceleration parameter to explain the expansion of the universe. Further, we study the validity of the generalized second law of thermodynamics in this scenario. Finally, we find out a cosmological implication of our work by evaluating the holographic dark energy equation of state for low red-shifts containing both varying G and c 2 parameter corrections. 相似文献
105.
106.
Abhijit Mahanta Nanda Kishor Gour Plaban Jyoti Sarma Raju Kumar Borah Prasanta Kumar Raul Ramesh Chandra Deka Ashim Jyoti Thakur Utpal Bora 《应用有机金属化学》2019,33(8)
A simple and convenient protocol has been developed for ipso‐nitration of arylboronic acid catalysed by molecular iodine at room temperature, using zirconium oxynitrate as the nitrating species. The protocol is applicable to electronically diverse aryl‐ and heteroarylboronic acid moieties under mild reaction conditions with good to excellent isolated yields. Furthermore, a theoretical investigation has been performed for the same reaction, and reaction profiles are modelled using modern density functional theory (DFT). DFT‐based results support the experimentally observed results. 相似文献
107.
Arun Jyoti Borah Progyashree Goswami Nabin C. Barua Prodeep Phukan 《Tetrahedron letters》2012,53(52):7128-7130
A synthetic pathway for the synthesis of unit-B of cryptophycin-24 has been developed using Sharpless asymmetric dihydroxylation as the key step. This study shows that direct azidation of α-hydroxy acid ester using diphenylphosphoryl azide is beneficial to asymmetric synthesis of α-amino acid without the loss of chirality during the transformation. 相似文献
108.
109.
We explore a novel possibility for lowering the solar mixing angle (θ
12) from tri-bimaximal mixings, without sacrificing the predictions of maximal atmospheric mixing angle (θ
23 = 45°) and zero reactor angle (θ
13 = 0°) in the inverted and normal hierarchical neutrino mass models having 2–3 symmetry. This can be done through the identification
of a flavour twister term in the texture of neutrino mass matrix and the variation of such term leads to lowering of solar
mixing angle. For the observed ranges of Δm
212 and Δm
232, we calculate the predictions on tan2
θ
12 = 0.5, 0.45, 0.35 for different input values of the parameters in the neutrino mass matrix. We also observe a possible transition
from inverted hierarchical model having even CP parity (Type-IHA) to inverted hierarchical model having odd CP parity (Type-IHB)
in the first two mass eigenvalues, when there is a change in input values of parameters in the same mass matrix. The present
work differs from the conventional approaches for the deviations from tri-bimaximal mixing, where the 2–3 symmetry is broken,
leading to θ
23 ≠ 45° and θ
13 ≠ 0°.
相似文献
110.
Kalita Amlan Jyoti Sahu Prem Prakash Borah Ritam Raj Rohman Shahnaz Sultana Kashyap Chayanika Ullah Sabnam Swabaka Baruah Indrani Mazumder Lakhya Jyoti Konwar Dimpul Guha Ankur Kanti 《Structural chemistry》2021,32(6):2313-2318
Structural Chemistry - Sandwich complexes find their interests among the chemists after the breakthrough discovery of ferrocene. Since then, a number of sandwich and half-sandwich complexes were... 相似文献