A comprehensive study of performance and reliability of P, As, andhybrid As/P nLDD junctions for deep-submicron CMOS logic technology

A comprehensive study of P, As, and hybrid As/P nLDD junctions is presented in terms of performance, reliability, and manufacturability for the first time. It is found that As junctions limit the performance of deep submicron devices due to unacceptable hot-carrier reliability, whereas a hybrid junction (light dose P added to medium dose As) dramatically improves hot-carrier reliability while maintaining high performance and manufacturability. For L_eff of 0.19 μm, using this hybrid junction in a manufacturing process, an inverter gate delay of 32 ps, dc hot carrier life time exceeding ten years, and off-state leakage below 30 pA/μm at 2.9 V have been achieved     

TP63 Is Significantly Upregulated in Diabetic Kidney

The role of tumor protein 63 (TP63) in regulating insulin receptor substrate 1 (IRS-1) and other downstream signal proteins in diabetes has not been characterized. RNAs extracted from kidneys of diabetic mice (db/db) were sequenced to identify genes that are involved in kidney complications. RNA sequence analysis showed more than 4- to 6-fold increases in TP63 expression in the diabetic mice’s kidneys, compared to wild-type mice at age 10 and 12 months old. In addition, the kidneys from diabetic mice showed significant increases in TP63 mRNA and protein expression compared to WT mice. Mouse proximal tubular cells exposed to high glucose (HG) for 48 h showed significant decreases in IRS-1 expression and increases in TP63, compared to cells grown in normal glucose (NG). When TP63 was downregulated by siRNA, significant increases in IRS-1 and activation of AMP-activated protein kinase (AMPK (p-AMPK-Th¹⁷²)) occurred under NG and HG conditions. Moreover, activation of AMPK by pretreating the cells with AICAR resulted in significant downregulation of TP63 and increased IRS-1 expression. Ad-cDNA-mediated over-expression of tuberin resulted in significantly decreased TP63 levels and upregulation of IRS-1 expression. Furthermore, TP63 knockdown resulted in increased glucose uptake, whereas IRS-1 knockdown resulted in a decrease in the glucose uptake. Altogether, animal and cell culture data showed a potential role of TP63 as a new candidate gene involved in regulating IRS-1 that may be used as a new therapeutic target to prevent kidney complications in diabetes.     

Polymers from renewable resources. I. Castor oil-based interpenetrating polymer networks: Thermal and mechanical properties

A number of polyurethanes (PUs) were synthesized by reacting castor oil with toluene-2,4-diisocyanate and hexamethylene diisocyanate and varying the NCO/OH ratio. All these polyurethanes were reacted with some acrylic monomers like ethyl acrylate, n-butyl acrylate, ethyl methacrylate, and butyl methacrylate using a crosslinker ethylene glycol dimethyl-acrylate and benzoyl peroxide as the initiator. The physicochemical properties of interpenetrating polymer networks (IPNs) are reported. Thermogravimetric analysis was used to study the thermal behavior of IPNs and the evaluation of kinetic parameters. Degradation mechanism has also been investigated. Some of the mechanical properties viz. tensile strength, shore-A hardness, elongation at break, etc. are also reported. © 1993 John Wiley & Sons, Inc.     

Grafting vinyl monomers onto silk fibers: Graft copolymerization of methyl methacrylate onto silk using acetylacetonate Mn(III) complex

The graft copolymerization of methyl methacrylate onto Mulberry silk fibers was studied in aqueous solution using Mn(acac)₃ as initiator. Perchloric acid was found to catalyze the reaction. The rate of grafting was investigated by varying the concentration of the monomer and the complex, acidity of the medium, the solvent composition of the reaction medium, the surfactants, and the inhibitors. The graft yield increases with increasing concentration of Mn(acac)₃ up to 0.01 mol/L, decreasing thereafter. Increase of MMA concentration up to 0.56 mol/L increases graft yield, and thereafter it decreases. Among the various vinyl monomers studied, MMA was found to be most suitable for grafting. Grafting increases up to 7.5 × 10^?3 mol/L of HClO₄ concentration, and thereafter it decreases. A suitable reaction scheme has been proposed and a rate equation has been derived. The energy of activation has been calculated from the Arrhenius plot. The chain transfer constants for various chain transfer solvents have been evaluated from the average molecular weight (M?) of grafted poly(methyl methacrylate).     

Grafting vinyl monomers onto silk fibers. II. Graft copolymerization of methyl methacrylate onto silk by hexavalent chromium ion

The feasibility of chromium(VI) to induce graft polymerization of methyl methacrylate onto silk was investigated. The rate of grafting was determined by varying monomer concentration, chromium(VI) concentration, temperature, acidity of the medium, nature of the silk, reaction medium, and redox system. The graft yield increased with increasing monomer concentration up to 0.65M, and with further increase of monomer the graft yield decreased. The graft yield increased with increasing chromium(VI) concentration. The grafting is considerably influenced by chemical modification of silk prior to grafting. The graft yield is influenced by thiourea concentration, decreasing with increasing thiourea concentration. The effect of certain inorganic salts and anionic surfactants on the rate of grafting was investigated.     

Field Validation of DNDC Model for Methane and Nitrous Oxide Emissions from Rice-based Production Systems of India

The DNDC (DeNitrification and DeComposition) model was tested against experimental data on CH₄ and N₂O emissions from rice fields at different geographical locations in India. There was a good agreement between the simulated and observed values of CH₄ and N₂O emissions. The difference between observed and simulated CH₄ emissions in all sites ranged from −11.6 to 62.5 kg C ha⁻¹ season⁻¹. Most discrepancies between simulated and observed seasonal fluxes were less than 20% of the field estimate of the seasonal flux. The relative deviation between observed and simulated cumulative N₂O emissions ranged from −237.8 to 28.6%. However, some discrepancies existed between observed and simulated seasonal patterns of CH₄ and N₂O emissions. The model simulated zero N₂O emissions from continuously flooded rice fields and poorly simulated CH₄ emissions from Allahabad site. For all other simulated cases, the model satisfactorily simulated the seasonal variations in greenhouse gas emission from paddy fields with different land management. The model also simulated the C and N balances in all the sites, including other gas fluxes, viz. CO₂, NO, NO₂, N₂ and NH₃ emissions. Sensitivity tests for CH₄ indicate that soil texture and pH significantly influenced the CH₄ emission. Changes in organic C content had a moderate influence on CH₄ emission on these sites. Introducing the mid-season drainage reduced CH₄ emissions significantly. Process-based biogeochemical modeling, as with DNDC, can help in identifying strategies for optimizing resource use, increasing productivity, closing yield gaps and reducing adverse environmental impacts.     

Grafting of vinyl monomers onto silk fibers: Trivalent-manganese-initiated graft copolymerization of acrylamide onto silk fibers

Graft copolymerization of acrylamide (AM) onto silk fibers, using Mn(III)–sulphate as initiator, has been investigated, in aqueous sulphuric acid in the temperature range of 30–55°C. Grafting reaction has been studied by varying the concentration of monomer, Mn(III), sulphuric acid, temperature, and also with the modified silk. The graft yield increases significantly with increase of monomer concentrations to the extent of 0.85M, after which the rate falls. With increase in Mn(III) concentration and H⁺ ion concentration the graft yield increases, but after an optimum concentration a depression in the graft yield is noticed. The rate of the reaction is temperature-dependent; with increase of temperature the graft-on increases. Among the solvent composition studied a solvent/water mixture containing 10% of the solvent seems to constitute the most favorable medium for grafting, and a further increase of solvent composition decreases the graft yield. The effect of various additives such as transition metal salts, aromatic and heterocyclic amines on grafting reaction has been studied. A suitable mechanism for grafting has been proposed. Finally physical characterization such as thermal analysis (TGA) of the grafted samples has been carried out in order to ensure grafting and to study the change in the properties of the fibers.     

Polymers from renewable resources. VIII. Thermal properties of the interpenetrating polymer networks derived from castor oil–isophorone diisocyanate–polyacrylamides

Castor oil was reacted with isophorone diisocyanate varying the isocyanate/hydroxyl ratio to produce a number of polyurethanes (PUs). All the PUs were reacted with acrylamide and methacrylamide using ethylene glycol dimethacrylate as the crosslinker and benzoyl peroxide as the initiator. Thermogravimetric analysis of the polymers was conducted using a computer analysis method for assigning the kinetic mechanism. The degradation steps have been discussed in the light of the kinetic parameters. © 1995 John Wiley & Sons, Inc.     

Grafting vinyl monomers onto wool fibers: Graft copolymerization of methyl methacrylate onto wool fibers using vanadyl acetyl acetonate complex

The graft copolymerization of methyl methacrylate (MMA) onto native and reduced Indian Chokla wool fibers was studied in aqueous solution using the acetylacetonate oxovanadium (IV) complex. The rate of grafting was investigated by varying the concentration of the monomer and the complex, acidity of the medium, and the solvent composition of the reaction medium. The graft yield increases with increasing concentration of the initiator up to 8.75 × 10^?5 mol/L, of the monomer up to 0.5634 mol/L, and thereafter it decreases. MMA was found to be the most active monomer when compared to other vinyl monomers. Grafting increases with increasing concentration of HClO₄ and with increasing temperature. Reduced and oxidized wools were found to be better substrates than untreated, esterified, crosslinked, and trinitrophenylated wools. The extent of grafting was mostly dependent upon the concentration of ? SH groups in case of reduced wool. A suitable reaction scheme has been proposed and the activation energy was calculated from Arrhenius plot.