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91.
92.
Amitabh Jain 《辐射效应与固体损伤》2013,168(1-4):39-46
The potential advantages of ion implantation have been exploited in virtually every kind of semiconductor device. Several commercially important devices owe their existence to this technique. Ion implantation provides precise control over the amount of dopant, concentration profile and lateral dimensions in device fabrication. The high degree of uniformity and reproducibility have made it possible to produce sophisticated devices and integrated circuits with high yield and tight tolerances. This is a truly planar process. It is possible to achieve high doping concentrations with relatively lower processing temperatures thereby avoiding lifetime degradation. The process is carried out in an inherently clean environment. A wide range of dopants is available and one is not limited by the particular properties of the substrate. There is great flexibility in choice of masking materials and self-alignment of doped regions in MOS devices is facilitated. The increasing impact of ion implantation on device technology is discussed with reference to some recent developments. Specific commercially manufactured devices are mentioned. Ion implantation machines continue to undergo development aimed at higher throughputs and cleaner vacuum. There is the need for greater reliability of machines. Effort is also directed at the development of low cost machines for dedicated applications. Design of implanted devices continues to be an empirical process in some respects. The ability to accurately predict profile shapes in samples implanted (perhaps through a screen oxide) and subject to complicated post-implantation process steps, would cut down development time and costs. 相似文献
93.
94.
R. Pankajavalli Ashish Jain Akanksha Sharma S. Anthonysamy V. Ganesan 《Journal of Thermal Analysis and Calorimetry》2013,112(1):83-93
The standard Gibbs energy of formation of M2TeO6 and M6TeO12 (where M = Sc, Y), was determined from its vapor pressure measurements by employing thermogravimetry-based transpiration technique. This technique was validated by measuring the vapor pressure of well-studied substances such as TeO2(s) and CdCl2(s). The temperature dependence of the vapor pressure of TeO2(g) over the mixtures M6TeO12 + M2O3 (where M = Sc, Y), generated by the incongruent vaporization reaction, M6TeO12(s) → 3M2O3(s) + TeO2(g) + ½O2(g) were measured in the temperature range 1,413–1,473 K and 1,623–1,743 K for Sc6TeO12(s) and Y6TeO12(s), respectively. Similarly, the vapor pressure of TeO2(g) over the mixtures M2TeO6(s) + M6TeO12(s) generated by the vaporization reaction, 3M2TeO6(s) → M6TeO12(s) + 2TeO2(g) + O2(g) was measured in the temperature range (1,223–1,293 K) and (1,333–1,423 K) for Sc2TeO6(s) and Y2TeO6(s), respectively. From the vapor pressure measurements, the standard Gibbs energy of formation of M6TeO12 and M2TeO6 were derived. 相似文献
95.
Jitender Gaur Shilpa Jain Rohit Bhatia Arun Lal Narender Kumar Kaushik 《Journal of Thermal Analysis and Calorimetry》2013,112(2):1137-1143
We demonstrate synthesis of water insoluble, novel copolymer PA1 from condensation of glyoxal dihydrazone and glyoxal dihydrazone bis(dithiocarbamate) monomers having high capacity to remove metal ions from aqueous solution. The presence of a high atomic percentage of nitrogen and sulfur atoms in PA1 leads to strong ligating ability with metal ions. The monomers and the polymer have been characterized by FTIR, UV–Visible spectroscopy, CHNS elemental analysis, NMR, MALDI-MS, and TG/DTA. As a proof of concept, the PA1 is tested for its ability to remove heavy metal ions Cu2+, Co2+, Fe2+, Ni2+, Mn2+, and CrO 7 2? from aqueous solutions. PA1 efficiently removed metals ions from the metal solutions. The highest absorption ability has been observed toward the iron salts where 0.969 g metal salt is absorbed by 1 g polymer. This study has implication for inexpensive and efficient polymer for purification of water. 相似文献
96.
Pranav Kumar Gutch Sharma Jitendra Shrivastava Alankar Jain Anurekha K. Ganesan 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1953-1958
Pralidoxime chloride known as 2-PAM chloride is used as antidote for nerve agent’s poisoning. This study was undertaken to establish the compatibility of 2-PAM chloride with a number of commonly used excipients by using thermoanalytical technique viz., differential scanning calorimetry (DSC) and thermogravimetry/differential thermogravimetry (TG/DTG) used in pharmaceutical formulation. The TG and DSC both results demonstrated that polyvinyl alcohol, polyacrylamide, microcrestline cellulose, hydroxypropyl cellulose, cellulose acetate, ethyl cellulose found to be compatible with 2-PAM chloride and chosen for the preparation of antidote against chemical warfare agents. 相似文献
97.
Amrita Jain S. K. Tripathi Ashish Gupta Manju Kumari 《Journal of Solid State Electrochemistry》2013,17(3):713-726
The present investigation deals with electrochemical double layer capacitors (EDLCs) made up of ionic liquid (IL)-based gel polymer electrolytes with chemically treated activated charcoal electrodes. The gel polymer electrolyte comprising of poly(vinylidine fluoride-co-hexafluropropylene) (PVdF-HFP)–1-ethyl-2,3-dimethyl-imidazolium-tetrafluroborate [EDiMIM][BF4]–propylene carbonate (PC)–magnesium perchlorate (Mg(ClO4)2) exhibits the highest ionic conductivity of ~8.4?×?10?3?S?cm?1 at room temperature (~20 °C), showing good mechanical and dimensional stability, suitable for their application in EDLCs. Activation of charcoal was done by impregnation method using potassium hydroxide (KOH) as activating agent. Brunauer–Emmett–Teller (BET) studies reveal that the effective surface area of treated activated charcoal powder (1,515 m2?g?1) increases by more than double-fold compared to the untreated one (721 m2?g?1). Performance of EDLCs has been tested using cyclic voltammetry, impedance spectroscopy, and charge–discharge techniques. Analysis shows that chemically treated activated charcoal electrodes have almost triple times more capacitance values as compared to the untreated one. 相似文献
98.
Aqueous solution of potassium persulfate converts water-insoluble carboxylic acids in ether (or dichloromethane), to peracids in a yield of 80–90% under the catalytic influence of benzyltriethylammonium chloride (BTEAC) or polyethyleneglycol (PEG-400). The reaction is further catalyzed kinetically in presence of a sulfonated polymer. 相似文献
99.
Archana Sivasubramaniyan Dinesh Murugan Ranganathan Raja Sathishkumar Murugan Shanmugavelan Poovan 《合成通讯》2013,43(23):2748-2763
An efficient synthesis of N-acyl/N-substituted acyl pyrazolines and their triazole hybrids have been accomplished via acylation of pyrazolines and pyrazoline-triazole hybrids with carboxylic acids and/or substituted carboxylic acids in the absence of activating agents/catalysts. In the present study, a mechanism envisaging the in situ generation of a new transient acylating intermediate has been proposed to explain the acylation. 相似文献
100.
Shreyans K. Jain Samdarshi Meena Asif K. Qazi Aashiq Hussain Sunil K. Bhola Rajendra Kshirsagar Koteppa Pari Anamika Khajuria Abid Hamid R. Uma Shaanker Sandip B. Bharate Ram A. Vishwakarma 《Tetrahedron letters》2013
The chromone alkaloid dysoline (1), a new regioisomer of rohitukine (2) along with rohitukine and rohitukine-N-oxide (3) were isolated from the stem barks of Dysoxylum binectariferum. The structure of dysoline (1) was determined by extensive 2D-NMR studies and the absolute configuration was established by NOESY and CD spectra. Dysoline (1) consisted of a 5,7-dihydroxy-2-methylchromone nucleus substituted with a 2′-hydroxylated N-Me piperidine ring at the C-6 position. Dysoline differs from rohitukine by the position of the piperidine ring on the chromone nucleus. Dysoline displayed promising cytotoxicity in HT1080 fibrosarcoma cells with an IC50 of 0.21 μM, and also displayed significant inhibition of proinflammatory cytokines TNF-α and IL-6. 相似文献