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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.
The solid + liquid phase diagram, drawn from thermal and dielectric measurements, is presented. It exibits a miscibility gap at 0.08 ≤ χ2 ≤ 0.58, and two eutectics. The occurrence of a (likely 1:1) intermediate compound, which decomposes on melting into two immiscible liquids, is postulated. Mixed crystals are observed in the sulfolane richer region.Deviations of the liquid mixtures from ideality, positive in the case of viscosity and negative in the case of dielectric constants, are evidenced. 相似文献
3.
[VIVO(acac)2] reacts with the methanolic solutions of tridentate dibasic ONO donor hydrazone ligands derived from the condensation of
benzoyl hydrazine with either 2-hydroxyacetophenone (H2L1) or its para-substituted derivatives (H2L2–4) (general abbreviation H2L), in the presence of vanillin (Hvan) in equimolar ratio under aerobic conditions generating the mixed-ligand oxovanadium(V)
complexes of the type [VVO(L)(van)], (1)–(4) in good yield. All the complexes are diamagnetic and exhibit only ligand-to-metal charge transfer (l.m.c.t.) band near 510 nm
in addition to intra-ligand (π → π*) transition band near 330 nm in CH2Cl2 solution. 1H-n.m.r. spectra of the complexes in CDCl3 solution indicate the presence of two isomeric forms [(1A), (1B); (2A), (2B); (3A), (3B) and (4A), (4B)] in different ratios, which is explained by the interchange of the two binding sites of van− motif between its coordinated equatorial and axial positions. Complexes display two quasi-reversible one electron reduction
peaks near +0.10 V and near +0.30 V versus s.c.e. in CH2Cl2 solution which are attributed to the successive reduction of VV→ VIV and the VIV→ VIII motifs, respectively. λmax (for l.m.c.t. transition), and the two reduction potential values (E
1/2)I (average of the first step anodic and first step cathodic peak potentials) and (E
1/2)II (average of the second step anodic and second step cathodic peak potentials) of the complexes, are found to be linearly related
to the Hammett constants (σ) of the substituents in the aryloxy ring of the hydrazone ligands. λmax, (E
1/2)I and (E
1/2)II values show large dependence: dλmax/dσ = 37.29 nm, d(E
1/2)I/dσ = 0.21 V and d(E
1/2)II/dσ = 0.21 V, respectively, on σ. 相似文献
4.
5.
Samavi Mahdieh Uprety Bijaya Kumar Rakshit Sudip 《Applied biochemistry and biotechnology》2019,189(2):626-637
Applied Biochemistry and Biotechnology - Poplar wood hemicellulose prehydrolysate was used for microbial oil production using an oleaginous microorganism Cryptococcus curvatus. Initially, the... 相似文献
6.
Pranita Bora Dr. Basanta Saikia Dr. Bipul Sarma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(3):699-710
Nucleation events and crystal growth can be guided by molecular recognition at interfaces through intermolecular interactions. The short-acting antimicrobial sulfa drug sulfathiazole is known for its concomitant crystallization, which has five known polymorphs, due to conformational flexibility and hydrogen-bond synthon variation. In its development stage of a drug the issue of concomitant crystallization needs to be addressed with respect to patent litigation, including legal actions to protect patents against infringement. A functional self-assembled monolayer (SAM) of organic thiol on a gold surface has been employed as an efficient approach to control concomitant nucleation of such flexible drugs. The crystallization on a SAM surface is mostly kinetically driven and often leads to the nucleation of novel metastable forms. Spectroscopic, thermal analysis and X-ray diffraction studies reveal that a previously unknown, sixth form of the drug nucleates on the designed SAM surface. 相似文献
7.
Dr. Keyur P. Somani Natvar K. Patel Sujata S. Kansara Animesh K. Rakshit 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4-5):797-811
The equilibrium swelling study of polyurethanes (PU) was carried out in various solvents in order to calculate their solubility parameter. The kinetics of swelling and sorption have also been studied in 1,4‐dioxane at 30°C. The PU was synthesized by reacting a novel polyol (castor oil derivative and epoxy based resin, EpxR) and one of the polyethylene glycols (PEG 200, PEG 400, PEG 600) with different weight compositions, with a toluene diisocyanate (TDI) adduct (derived from toluene diisocyanate and R60 polyol). Different NCO/OH ratio viz. 1, 1.3 and 1.7 were employed in the study. The results were found to vary with the weight composition of polyol components, as well as the crosslink density of the samples. The sorption behavior is also found to vary with the molecular weight of polyethylene glycol employed in the preparations of the polyurethanes. Kinetic studies of swelling revealed that the sorption is anomalous in nature. The diffusion coefficient (D) increased with an increase in the NCO/OH ratio and decreased with an increase in chain length of polyethylene glycol. The sorption coefficient (S) decreased with an increase in crosslink density (NCO/OH) and increased with increasing polyethylene glycol (i.e., PEG 200, PEG 400, and PEG 600) moieties in the polyurethanes. The molecular weight between two crosslink points was calculated using the Flory Rehner equation (24), and hence, the number of chains per unit volume (N) and degree of crosslinking (ν) in all the samples were determined. 相似文献
8.
9.
Recently a novel phase of ZnO has been synthesized which is analogous to α-boron nitride, although more three dimensional, and consists of planar hexagonal sheets of ZnO. Examining the dynamic stability of the structure, we find unstable phonon modes over a considerable part of the Brillouin zone. Local-density approximation (LDA) and generalized gradient approximation level calculations have usually been able to predict the structural stability of s-p bonded systems. The failure in the present case is a surprise and is traced to the self-interaction error which incorrectly locates the localized Zn d states in the valence band of ZnO. Correcting for this with a Hubbard-like U on the Zn d states, the optimized structure is predicted to be stable. This highlights the fact that the large bond length contraction that one finds in going from sp(3)- to sp(2)-type bonding results in an increased necessity to correct for self-interaction errors. 相似文献
10.
Thin films of ZnO-SnO2 composites have been deposited on Si(1 0 0) and glass substrates at 500 °C by pulsed laser ablation using different composite targets with ZnO amount varying between 1 and 50 wt%. The effect of increasing ZnO-content on electrical, optical and structural properties of the ZnO-SnO2 films has been investigated. X-ray diffraction analysis indicates that the as-deposited ZnO-SnO2 films can be both crystalline (for ZnO <1 wt%) and amorphous (for ZnO ≥ 10 wt%) in nature. Atomic force microscopy studies of the as-prepared composite films indicate that the surfaces are fairly smooth with rms roughness varying between 3.07 and 2.04 nm. The average optical transmittance of the as-deposited films in the visible range (400-800 nm), decreases from 90% to 72% for increasing ZnO concentration in the film. The band gap energy (Eg) seems to depend on the amount of ZnO addition, with the maximum obtained at 1 wt% ZnO. Assuming that the interband electron transition is direct, the optical band gap has been found to be in the range 3.24-3.69 eV for as-deposited composite films. The lowest electrical resistivity of 7.6 × 10−3 Ω cm has been achieved with the 25 wt% ZnO composite film deposited at 500 °C. The photoluminescence spectrum of the composite films shows a decrease in PL intensity with increasing ZnO concentration. 相似文献