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91.
The goal of this article is two fold. First, using transcendental shift-like automorphisms of \(\mathbb C^k, ~k \ge 3\) we construct two examples of non-degenerate entire mappings with prescribed ranges. The first example exhibits an entire mapping of \(\mathbb C^k, ~k \ge 3\) whose range avoids a given polydisc but contains the complement of a slightly larger concentric polydisc. This generalizes a result of Dixon–Esterle in \(\mathbb C^2.\) The second example shows the existence of a Fatou–Bieberbach domain in \(\mathbb C^k,~k \ge 3\) that is constrained to lie in a prescribed region. This is motivated by similar results of Buzzard and Rosay–Rudin. In the second part we compute the order and type of entire mappings that parametrize one dimensional unstable manifolds for shift-like polynomial automorphisms and show how they can be used to prove a Yoccoz type inequality for this class of automorphisms. 相似文献
92.
In this paper, we have introduced a Solid Transportation Problem where the constrains are mixed type. The model is developed under different environment like, crisp, fuzzy and intuitionistic fuzzy etc. Using the interval approximation method we defuzzify the fuzzy amount and for intuitionistic fuzzy set we use the ($\alpha,\beta$)-cut sets to get the corresponding crisp amount. To find the optimal transportation units a time and space based with order of convergence $O (MN^2)$ meta-heuristic Genetic Algorithm have been proposed. Also the equivalent crisp model so obtained are solved by using LINGO 13.0. The results obtained using GA treats as the best solution by comparing with LINGO results for this present study. The proposed models and techniques are finally illustrated by providing numerical examples. Degree of efficiency have been find out for both the algorithm. 相似文献
93.
P. K. Sinha P. M. Satyasai R. Shankar R. Muthiah S. Bera S. V. Narasimhan A. N. Pandey A. Jaleel 《Journal of Radioanalytical and Nuclear Chemistry》1999,242(2):341-348
An intermediate level liquid waste (ILLW or Category III waste) stream was treated for the removal of radioactive Cs in pilot
scale experiments, using three different ion exchange media. Results indicated that the polyacrylic fibre coated with cupric
ferric hexacyanoferrate (CuFeHCF-fibre composite) was the most efficient, followed by cupric hexacyanoferrate loaded ion exchange
resin (CuHCF-resin) and mixed zeolites (AR-1, 4A and 13X in the ratio 6:1:1). The mixed zeolites column and the CuFeHCF-fibre
column were used in series in order to get a high total decontamination factor (DF). Leaching studies on the CuFeHCF-fibre
composite loaded with137Cs, in demineralised (DM) water, tap water and ground water media indicated a release of about 19.3%, 25.5% and 41.3% of137Cs, respectively, in a period of about 8 months. XPS studies with CuFeHCF-fibre composite indicated some chemical interaction
between the CuFeHCF precipitate and the polyacrylic fibre. Some of the possible disposal options for the CuFeHCF-fibre composite
have also been discussed. 相似文献
94.
I. Bhattacharyya N. C. Bera A. K. Das 《International journal of quantum chemistry》2008,108(3):447-455
Stability, structural properties, and dissociation pathways of silylidyne‐amines FSiN, ClSiN, their isomers, and silylidyne‐phosphanes FSiP and ClSiP have been studied in detail using ab initio MP2, CCSD, and CCSD(T) and density functional B3LYP methods. After dissociation of FSiN, ClSiN, FSiP, and ClSiP, the fragmented atoms have been considered to be either in their ground state or in their metastable state in various dissociation channels. The dissociation energy for various dissociation pathways has been compared and interesting results have been obtained for the dissociation channels where the fragmented atoms are in their metastable states. The structure properties of these molecules agree well with the theoretical results wherever available. The NBO atomic charges of these molecules have been analyzed. The isomerization energy has been compared with existing theoretical data. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 相似文献
95.
G.K. Paul R. Ghosh S.K. Bera S. Bandyopadhyay T. Sakurai K. Akimoto 《Chemical physics letters》2008,463(1-3):117-120
Deep levels in polycrystalline p-Cu2O/i-ZnO/n-ZnO/glass photovoltaic structures were studied by deep level transient spectroscopy (DLTS). Post-deposition crown-ether cyanide (CN) treatments of the samples were performed with the variation of time. DLTS spectra for all samples showed the presence of two traps localized at 0.2 eV and 0.5 eV from the top of the valence band. Effects of defect passivation and improvement of cell performance were demonstrated with the cyanide treated samples. Optimum time of cyanide treatment was found to be 3 min. Cell performance was increased from 0.4% to 0.7% for the samples undergoing the optimum post-deposition cyanide treatment. 相似文献
96.
Percec V Barboiu B Grigoras C Bera TK 《Journal of the American Chemical Society》2003,125(21):6503-6516
A new synthetic concept named TERMINI that stands for irreversible TERminator Multifunctional INItiator is reported. Suitable combinations of TERMINI and living polymerizations provide access to strategies for the design and synthesis of unprecedented complex molecular and macromolecular architectures from a diversity of commercial monomers. TERMINI represents a masked multifunctional initiator designed to quantitatively and irreversibly interrupt a chain organic reaction or a living polymerization. After demasking, the TERMINI repeat unit enables the quantitative reinitiation, in the presence or absence of a catalyst, of the same or a different living polymerization or a chain organic reaction in more than one direction, thus becoming a branching point. The demonstration of this concept was made by using a combination of metal-catalyzed living radical polymerization (LRP) and (1,1-dimethylethyl)[[1-[3,5-bis(S-phenyl 4-N,N'-diethylthiocarbamate)phenyl]ethenyl]oxy]dimethylsilane as TERMINI, to elaborate a novel iterative divergent method for the synthesis of dendritic macromolecules based on methyl methacrylate (MMA). 相似文献
97.
98.
Mallick A Haldar B Maiti S Bera SC Chattopadhyay N 《The journal of physical chemistry. B》2005,109(30):14675-14682
Photophysical properties of 3-acetyl-4-oxo-6,7-dihydro-12H-indolo[2,3-a]quinolizine (AODIQ), a bioactive molecule, has been investigated in well-characterized, monodispersed biomimicking nanocavities formed by sodium bis(2-ethylhexyl)sulfosuccinate (AOT) in heptane using steady-state and picosecond time resolved fluorescence and fluorescence anisotropy. The emission behavior of AODIQ is very much dependent upon the water/surfactant mole ratio (W), i.e., on the water pool size of the reverse micellar core. AODIQ exhibits a sharp decrease in fluorescence anisotropy with increasing W, implying that the overall motional restriction experienced by the molecule is decreased with increased hydration. Some of the depth-dependent relevant fluorescence parameters, namely, fluorescence maxima and fluorescence anisotropy (r), have been monitored for exploiting the distribution and microenvironment around the probe in the reverse micelles. Fluorescence spectral position and fluorescence quenching studies suggest that the probe does not penetrate into the reverse micellar core; rather it binds at the interfacial region. Quantitaive estimates of the micropolarity and microviscosity at the binding sites of the probe molecule have been determined as a function of W. 相似文献
99.
Dafei Yuan Mohammad A. Awais Valerii Sharapov Xunshan Liu Andriy Neshchadin Wei Chen Mrinal Bera Luping Yu 《Chemical science》2020,11(41):11315
A critical issue in developing high-performance organic light-emitting transistors (OLETs) is to balance the trade-off between charge transport and light emission in a semiconducting material. Although traditional materials for organic light-emitting diodes (OLEDs) or organic field-effect transistors (OFETs) have shown modest performance in OLET devices, design strategies towards high-performance OLET materials and the crucial structure–performance relationship remain unclear. Our research effort in developing cross-conjugated weak acceptor-weak donor copolymers for luminescent properties lead us to an unintentional discovery that these copolymers form coiled foldamers with intramolecular H-aggregation, leading to their exceptional OLET properties. An impressive external quantum efficiency (EQE) of 6.9% in solution-processed multi-layer OLET devices was achieved.Coiled foldamers with intramolecular H-aggregation in semi-ladder copolymers lead towards the highest EQE of 6.9% in solution-processed multi-layer OLETs. 相似文献
100.
Synthesis of isonucleosides 13 , 14 , 16 , and 17 , bearing an exocyclic methylidene group at the sugar moiety, starting from a 3‐keto sugar is described. The keto compound was converted to the methylene‐sugar 10b (Scheme 1), which was coupled with nucleobases by means of the Mitsunobu reaction. The coupling reaction with adenine and 8‐azaadenine produced both the N9‐ and N3‐nucleosides (see 13 and 14 , resp.; Scheme 2). The structures of 13a and 14a were confirmed by single‐crystal X‐ray data. Synthesis of the pyrimidine compounds was also approached from the β‐amino sugar 20 that was prepared using a Gabriel‐synthesis methodology (Scheme 3). 相似文献