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1.
Raj Gandhi Kamales Kar S. Uma Sankar Abhijit Bandyopadhyay Rahul Basu Pijushpani Bhattacharjee Biswajoy Brahmachari Debrupa Chakraborti M. Chaudhury J. Chaudhury Sandhya Choubey E. J. Chun Atri Desmukhya Anindya Datta Gautam Dutta Sukanta Dutta Anjan Giri Sourendu Gupta Srubabati Goswami Namit Mahajan H. S. Mani A. Mukherjee Biswarup Mukhopadhyaya S. N. Nayak M. Randhawa Subhendu Rakshit Asim K. Ray Amitava Raychaudhuri D. P. Roy Probir Roy Suryadeep Roy Shiv Sethi G. Sigl Arunansu Sil N. Nimai Singh Mark Vagins Urjit Yagnik 《Pramana》2003,60(2):405-409
This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in
long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed. 相似文献
2.
Gas-phase proton affinities of cyclophanes containing intra-annular amino groups were calculated using density functional theory (DFT) at the B3LYP/6-31+G∗∗//B3LYP/6-31G∗ level. They are higher in magnitude as those for proton sponges such as 1,8-bisaminonaphthalene, however, they are slightly weaker bases than 1,8-bis(dimethylamino)naphthalene. The high basicity of the cyclophane diamines is attributed mainly to their structural flexibility, which allows them to maximize the hydrogen bond strength in the cations by achieving N-H?N linearity, while strain relief upon protonation is less important. Another contributing factor is the stabilizing interaction of the added proton with adjacent phenyl π systems of the cyclophanes. Barriers for proton transfer between the nitrogen atoms of the diamine cations are also reported. 相似文献
3.
A method for selective extraction of Mn(II) with dithizone and potassium thiocyanate has been described. The method involves formation of a Mn(II)-thiocyanate-dithizone complex in a hexamine medium containing potassium thiocyanate (2.8M), dithizone (5.5-6.5 x 10(-5)M) and hydroxylamine hydrochloride (0.25%) at pH approximately 6 followed by extraction of the complex on polyurethane foam using batch squeezing mode within 1 hr. The sorbed Mn-thiocyanate-dithizone complex is eluted with acetone and made alkaline with 0.5 ml of a stabilizer solution (19 ml 2M NH(3) solution + 1 ml 5% hydroxylamine hydrochloride). The absorbance of the solution is measured at 506 nm. The adverse effect due to Pb may be obviated by separating the Pb as the sulphate during decomposition of sample and that due to iron may be removed before extraction of Mn by any suitable method. The other interfering elements (Cd, Zn, Ni, Co, Cu, etc.) are masked with KCN (6 x 10(-3)M optimum) solution. The method obeys Beer's Law from 0.1 to 2.0 mug Mn/ml. The method has been applied to various silicates, carbonates and glasses. 相似文献
4.
Arylazoimidazoles (2) are N,N-chelating ligands. The polymerization trend of the azolate system is restricted via N(1)-benzylation. The parent molecules (2), N(1)-benzylated products (3) and palladium complexes (4) were made by standard methods. The ligands (3) and complexes (4) are new. They have been characterized by elemental analysis, i.r., u.v.-vis. and high resolution 1H-n.m.r. spectral data. Redox studies were carried out by cyclic voltammetry. On complexation, azo reduction is shifted anodically. 相似文献
5.
Aryl bromides (3 equiv) were coupled efficiently with triarylbismuths (1 equiv) in an atom-efficient way using the Pd(OAc)2/PPh3 catalytic system in the presence of K3PO4 as base in DMF at 90 °C, providing excellent yields of the cross-coupled biaryls in short reaction times. 相似文献
6.
A. Bhattacharya A. Chandra B. Chakraborti 《International Journal of Theoretical Physics》2012,51(1):206-212
The mass splitting and the decay width of pentaquark (Θ+) at the higher angular momentum states have been investigated in the framework of flux tube model considering the diquark-diquark-antiquark
configuration for Θ+ along with statistical model. A quasi particle model for diquark has been considered. The Regge trajectory of Θ+ has also been investigated with interesting some observations. 相似文献
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An extremely short synthesis of 2,2-dimethyl-3-hydroxymethyl cyclopentanone 2 (R1 = R2 = Me), an advanced intermediate in the synthesis of the pheromone planococcyl acetate 3, is described. 相似文献
10.