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991.
Amir N. Hanna Galo A. Torres Sevilla Mohamed T. Ghoneim Aftab M. Hussain Rabab R. Bahabry Ahad Syed Muhammad M. Hussain 《固体物理学:研究快报》2014,8(3):248-251
We demonstrate a new thin film transistor (TFT) architecture that allows expansion of the device width using continuous fin features – termed as wavy channel (WC) architecture. This architecture allows expansion of transistor width in a direction perpendicular to the substrate, thus not consuming extra chip area, achieving area efficiency. The devices have shown for a 13% increase in the device width resulting in a maximum 2.5× increase in ‘ON’ current value of the WCTFT, when compared to planar devices consuming the same chip area, while using atomic layer deposition based zinc oxide (ZnO) as the channel material. The WCTFT devices also maintain similar ‘OFF’ current value, ~100 pA, when compared to planar devices, thus not compromising on power consumption for performance which usually happens with larger width devices. This work offers an interesting opportunity to use WCTFTs as backplane circuitry for large‐area high‐resolution display applications. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
992.
Shikha Pervin Khandaker S. Ashrafi M. S. Zobaer Md. Salahuddin A. A. Mamun 《Central European Journal of Physics》2014,12(11):799-804
The nonlinear propagation of the dust-acoustic (DA) waves in a strongly coupled dusty plasma containing Maxwellian electrons, nonthermal ions, and positively charged dust is theoritically investigated by a Burgers equation. The effects of the polarization force (which arises due to the interaction between electrons and highly positively charged dust grains) and nonthermal ions are studied. DA shock waves are found to exist with positive potential only. It represents that the strong correlation among the charged dust grains is a source of dissipation, and is responsible for the formation of DA shock waves. The effects of polarization force and nonthermal ions significantly modified the basic features of DA shock waves in strongly coupled dusty plasma. 相似文献
993.
Near-optimization is as sensible and important as optimization for both theory and applications. This paper deals with necessary and sufficient conditions for near-optimal singular stochastic controls for nonlinear controlled stochastic differential equations of mean-field type, which is also called McKean–Vlasov-type equations. The proof of our main result is based on Ekeland’s variational principle and some estimates of the state and adjoint processes. It is shown that optimal singular control may fail to exist even in simple cases, while near-optimal singular controls always exist. This justifies the use of near-optimal stochastic controls, which exist under minimal hypotheses and are sufficient in most practical cases. Moreover, since there are many near-optimal singular controls, it is possible to select among them appropriate ones that are easier for analysis and implementation. Under an additional assumptions, we prove that the near-maximum condition on the Hamiltonian function is a sufficient condition for near-optimality. This paper extends the results obtained in (Zhou, X.Y.: SIAM J. Control Optim. 36(3), 929–947, 1998) to a class of singular stochastic control problems involving stochastic differential equations of mean-field type. An example is given to illustrate the theoretical results. 相似文献
994.
Purification,Characterization and N‐terminal Sequence Analysis of Betel Leaf (Piper betle) Invertase
The present study is the first report describing the purification, enzymatic properties and N‐terminal amino acid sequence of a native invertase in betel leaf. The invertase was purified as a monomeric glycoprotein of molecular mass (Mr) 68 kDa. The enzyme was capable to attack β‐fructofuranoside linkages from the fructose end of sucrose, raffinose and stachyose indicating it as an authentic β‐D‐fructofuranosidase with high specificity for sucrose (Km 4.83 mM). The maximum activity was detected at pH 5.2 and 37 °C. Glucose and fructose showed typical inhibitory effect on the enzyme activity where as lectin was found to be effective activators of the enzyme. Significant inhibition by heavy metal ion Hg2+ and sulfhydryl group modifying agents suggesting that free sulfhydryl group containing amino acid, cysteine is necessary for the catalytic activity of the invertase. A BLAST search of the N‐terminal amino acid sequence of betel leaf invertase showed significant homology with the homologous invertases in database. 相似文献
995.
Asad Muhammad Khan Syed Sakhawat Shah 《Journal of Dispersion Science and Technology》2013,34(9):1247-1254
Ultraviolet (UV) and Fourier transformed infrared (FTIR) spectra of ciprofloxacin hydrochloride (Cpf) were studied under different pH conditions. The effect of aqueous, strong acidic, (pH 0.5–1.0) and a basic (pH 9.2) conditions on spectral behavior of Cpf was investigated in aqueous as well as in micellar environment of sodium dodecyl sulfate (SDS). Cpf shows partitioning from aqueous to micellar phase in a strong acidic as well as in a basic environment. Cpf shows no partitioning or binding to micelle in aqueous phase. Conductivity studies show that critical micelle concentration of SDS is increased with increasing concentration of Cpf. Different sites are responsible for binding under different pH conditions. 相似文献
996.
A novel polystyrene-supported palladium(II) complex, an excellent and recyclable catalyst, was synthesized for Sonogashira reactions. The present complex shows high catalytic activity for Sonogashira cross-coupling reaction of aryl halides with phenylacetylene under phosphine-free and copper-free reaction conditions in aqueous (DMF–H2O) medium. The catalyst could be reused for at least six reaction cycles with almost unchanged catalytic properties.
997.
Shirong Lu Tienan Jin Takeshi Yasuda Ashraful Islam Md. Akhtaruzzaman Liyuan Han Khalid A. Alamry Samia A. Kosa Abdullah Mohamed Asiri Yoshinori Yamamoto 《Tetrahedron》2013,69(4):1302-1306
A new series of functional 2-benzyl-1,2-dihydro[60]fullerenes, BnHCs, were synthesized efficiently via co-catalyzed selective monofunctionalization of C60 with functional benzyl bromides. Photophysical and electrochemical properties of the new BnHCs were investigated. PSCs based on 2-MeO–4-CO2Me–BnHC as new acceptor and P3HT as donor showed a power conversion efficiency of 3.75%, which is comparable to that of PC61BM under the same device conditions. 相似文献
998.
Imran Ali Hashmi Afshan Aslam Syed Kashif Ali Viqar-uddin Ahmed Firdous Imran Ali 《合成通讯》2013,43(19):2869-2874
Hydantoins, thiohydantoins, and glycocyamidines have been prepared in moderate to excellent yields at room temperature under solvent-free conditions. 3N-amino and carboamide derivatives of hydantoin (7–8) were prepared in single step by condensing benzil with semicarbazide and biuret respectively. 相似文献
999.
Rajibul A. Laskar Naznin A. Begum Mohammad Hedayetullah Mir Md. Rumum Rohman Abu T. Khan 《Tetrahedron letters》2013
Various aromatic aldehydes on reaction with 2-mercaptoethanol provided an unanticipated product, bis(2-hydroxyethyl)dithioacetals (3) as the major product along with the expected product 1,3-oxathiolanes (4) in the presence of 0.05 equiv amount of nickel(II) chloride hexahydrate (NiCl2·6H2O) under solvent-free conditions. Products 3c and 3e exhibit an interesting hydrogen-bonded infinite supra-molecular helical structure. 相似文献
1000.
Surfactants/polymers are used extensively in drug delivery as drug carriers. We herein report the effect of surfactants and polymers on the cloud point (CP) of amphiphilic drug chlorpromazine hydrochloride. At fixed drug concentration (50 mM) and pH (6.7) these additives affect the CP in accordance to their nature and structure: anionic surfactants show an increase followed by a decrease, whereas cationic (conventional as well as gemini) and nonionic surfactants show continous increase. The behavior with polymers is dictated by the number of units present in a particular polymer. Increase in drug concentration and pH, in presence of fixed amounts of CTAB, increases and decreases the CP, respectively. Variation of CP with pH at various fixed gemini concentrations shows that gemini surfactants are better candidates for drug delivery. 相似文献