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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.
Majumdar A Behnke JF Hippler R Matyash K Schneider R 《The journal of physical chemistry. A》2005,109(41):9371-9377
Chemical reactions in a dielectric barrier discharge at medium pressure of 250-300 mbar have been studied in CH(4)/Ar and CH(4)/N(2) gas mixtures by means of mass spectrometry. The main reaction scheme is production of H(2) by fragmentation of CH(4), but also production of higher order hydrocarbon molecules such as C(n)H(m) with n up to 9 including formation of different functional CN groups is observed. Formation of C(2)H(2), C(2)H(4), and C(2)H(6) molecules has been investigated in some detail. Significant differences are noted in comparison to a theoretical estimate. 相似文献
3.
We look at some one-dimensional semi-infinite superlattices with an underlying Hamiltonian that is of the nearest neighbour, tight binding type. A real space rescaling procedure which is exact in one dimension is applied to obtain the location of the subbands. It has been found that these subbands never overlap in 1D, and we interpret this as a band repulsion effect. Relevance in the case of a disordered system where this band repulsion crosses over to the well-known level repulsion is discussed. Then with a proper matching at the boundary we solve for the sets of denumerably infinite number of decaying solutions (the surface states) in the gaps. These types of states have been proposed quite some time ago. We look at detail theirexact analytical solutions in 1D and find that their decay lengths near the band edges diverge as |E–E
b|–v, wherev=1/2 andE
b is the nearest band edge. The decay lengths and their divergence exponent match extremely well with those obtained from transfer matrix method. Some recent experiments on quantum well structures seem to have observed such states. 相似文献
4.
Periodic first principle calculation correlates the role of metal substitution (Sr and Ba in place of Ca) on selective encaging of active O− radicals inside the microporous 12MO, 7Al2O3 crystal structure. We have exchanged Ca by Sr and Ba and as well extracted electron stepwise to monitor selectivity of different anion encaging inside the same structure type. Ca favors O2− encaging and shows no electron transition when neutral, whereas Sr shows no transition in absence of unpaired electron and can successfully trap O−, Ba though less active than the other metal substituents shows oxygen encaging at its zero and mono-positive state. 相似文献
5.
A general route for the synthesis of highly substituted aryl cyclopentanes has been developed involving Diels-Alder reaction of asymmetric dienes prepared from (+)-camphoric acid followed by aromatization of the resulting cyclohexene derivatives. Employing this protocol enantiospecific synthesis of (+)-herbertene and (+)-cuparene has been accomplished. 相似文献
6.
Kaviyarasi Renu Anirban Goutam Mukherjee Uddesh Ramesh Wanjari Sathishkumar Vinayagam Vishnu Priya Veeraraghavan Balachandar Vellingiri Alex George Ricardo Lagoa Kamaraj Sattu Abhijit Dey Abilash Valsala Gopalakrishnan 《Molecules (Basel, Switzerland)》2022,27(17)
Heavy metals and metalloids like cadmium, arsenic, mercury, and lead are frequently found in the soil, water, food, and atmosphere; trace amounts can cause serious health issues to the human organism. These toxic trace elements (TTE) affect almost all the organs, mainly the heart, kidney, liver, lungs, and the nervous system, through increased free radical formation, DNA damage, lipid peroxidation, and protein sulfhydryl depletion. This work aims to advance our understanding of the mechanisms behind lipid accumulation via increased free fatty acid levels in circulation due to TTEs. The increased lipid level in the myocardium worsens the heart function. This dysregulation of the lipid metabolism leads to damage in the structure of the myocardium, inclusive fibrosis in cardiac tissue, myocyte apoptosis, and decreased contractility due to mitochondrial dysfunction. Additionally, it is discussed herein how exposure to cadmium decreases the heart rate, contractile tension, the conductivity of the atrioventricular node, and coronary flow rate. Arsenic may induce atherosclerosis by increasing platelet aggregation and reducing fibrinolysis, as exposure interferes with apolipoprotein (Apo) levels, resulting in the rise of the Apo-B/Apo-A1 ratio and an elevated risk of acute cardiovascular events. Concerning mercury and lead, these toxicants can cause hypertension, myocardial infarction, and carotid atherosclerosis, in association with the generation of free radicals and oxidative stress. This review offers a complete overview of the critical factors and biomarkers of lipid and TTE-induced cardiotoxicity useful for developing future protective interventions. 相似文献
7.
8.
Pranesh Chowdhury Abhijit Hazra Maloy Kr. Mondal Bishnupada Roy Debiprasad Roy Shyama Prasad Bayen 《高分子科学杂志,A辑:纯化学与应用化学》2019,56(8):773-780
Poly(acrylic acid) (PAA) and its salt poly(acrylate) (PA) have been synthesized through modified free radical polymerization in environmentally begin aqueous medium under ultrasound to make the process robust. The synthesized polymer is well-characterized through conventional techniques. Its salt is employed to produce highly stable and stimuli sensitive colloidal silver (Ag-PA sol) without using any additional reducing chemical reagents like sodium borohydride, ascorbic acid, hydrazine, etc or UV/Gamma radiation. A detailed mechanistic path of the polymerization and reduction of Ag+ on polyacrylate chains has been evaluated. Finally Ag-PA sol is used for pH sensing through naked eye to eliminate the need for sophisticated instrument for data collection. The present work focuses mainly the development of a low cost pH sensing system based on colorimetric ‘smart polymer’ having high practical utility. The unique structural and photo-physical features of nano-scaled materials open new opportunities for the applications of colorimetric pH sensor. In the present work, Ag nano-clusters capped by PA? are employed as an effective colorimetric pH sensor for the first time, requiring no further functionalization. 相似文献
9.
Abhijit Chandra Roy V.S. Nisha Chetna Dhand Md. Azahar Ali B.D. Malhotra 《Analytica chimica acta》2013
We report results of the studies relating to the fabrication and characterization of a conducting polymer based molecularly imprinted para-nitrophenol (PNP) sensor. A water pollutant, para-nitrophenol is electrochemically imprinted with polyvinyl sulphonic acid (PVSA) doped polyaniline onto indium tin oxide (ITO) glass substrate. This PNP imprinted electrode (PNPI-PANI-PVSA/ITO) prepared via chronopotentiometric polymerization and over-oxidation is characterized by Fourier transform infra-red spectroscopy (FT-IR), UV–visible (UV–vis) spectroscopy, contact angle (CA), scanning electron microscopy (SEM), cyclic voltammetry (CV) and differential pulse voltammetry (DPV) studies. The response studies of PNPI-PANI-PVSA/ITO electrode carried out using DPV reveal a lower detection limit of 1 × 10−3 mM, improved sensitivity as 1.5 × 10−3 A mM−1 and stability of 45 days. The PNPI-PANI-PVSA/ITO electrode shows good precision with relative standard deviation of 2.1% and good reproducibility with standard deviation of 3.78%. 相似文献
10.
Dr. Abhijit Saha Dr. Jozef Adamcik Dr. Sreenath Bolisetty Stephan Handschin Prof. Dr. Raffaele Mezzenga 《Angewandte Chemie (International ed. in English)》2015,54(18):5408-5412
Self‐assembly of the naturally occurring sweetening agent, glycyrrhizic acid (GA) in water is studied by small‐angle X‐ray scattering and microscopic techniques. Statistical analysis on atomic force microscopy images reveals the formation of ultralong GA fibrils with uniform thickness of 2.5 nm and right‐handed twist with a pitch of 9 nm, independently of GA concentration. Transparent nematic GA hydrogels are exploited to create functional hybrid materials. Two‐fold and three‐fold hybrids are developed by introducing graphene oxide (GO) and in situ‐synthesized gold nanoparticles (Au NPs) in the hydrogel matrix for catalysis applications. In the presence of GO, the catalytic efficiency of Au NPs in the reduction of p‐nitrophenol to p‐aminophenol is enhanced by 2.5 times. Gold microplate single crystals are further synthesized in the GA hydrogel, expanding the scope of these hybrids and demonstrating their versatility in materials design. 相似文献