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101.
Device quality hydrogenated amorphous silicon films (a-Si:H) are deposited at a high deposition rate (4–5 Å/s) using a mixture of argon and hydrogen-diluted silane. The films exhibit good opto-electronic properties and show less degradation upon light soaking. Light-induced changes in conductivity could be annealed at much lower temperature. The presence of Ar* and atomic hydrogen in plasma replaces the weak Si-Si bonds, which are responsible for light-induced degradation by strong Si-Si bonds. This results in the improved stability of the films. 相似文献
102.
Schiff base liquid crystal dimers, both symmetric and non‐symmetric, in which two anisotropic groups are linked by a flexible spacer, exhibit a rich variety of smectic mesomorphism. The interest in this class of mesogens stems not only from their ability to act as model compounds for semi‐flexible mainchain liquid crystal polymers but also from their quite different properties compared to conventional low molar mass liquid crystals (monomers). We report here the phase transition studies on two examples of these schiff base liquid crystal dimers using the Differential Scanning Calorimetry and density measurements as a function of temperature. The symmetric liquid crystal dimer, α,ω‐bis (4‐n‐dodecylaniline benzylidene‐4′‐oxy)decane (10.O12O.10) exhibits a very rare Isotropic to G transition. Where as, the non‐symmetric dimer, α‐(4‐cyano biphenyl‐4′‐yloxy)‐ω‐(4‐n‐decylanilinebenzylidene‐4′‐oxy)decane (CB.O10O.10) exhibits a rare nematic to intercalated smectic A phase transition. The transitions studied, isotropic to nematic and isotropic to G exhibit a large density jump at the transition confirming their first order nature. Nematic to intercalated smectic A transition is found to be a second order transition whose behavior is similar to nematic to smectic A transition. Calculated values of pressure dependence of transition temperature and thermal expansion coefficient are also reported. 相似文献
103.
Materials having long afterglow are highly sought after for various applications such as light‐emitting diodes, security signs and bioimaging. Herein, we report a simple, low‐cost synthesis of a purely organic room‐temperature phosphorescent nanomaterial with a pebble‐like structure by heating urea, a biocompatible and easily available precursor, at 200 °C with a high phosphorescence lifetime of 1.0365 s and a visible afterglow for up to 10 s. This urea derived phosphorescent nanocomposite (UPNC) can be mixed with commercially available acrylic paint base and common gum, which can be readily used as a phosphorescent pigment. 相似文献
104.
105.
Samim Sultana Shreemoyee Bordoloi Surajit Konwer Geetika Borah Pradip K. Gogoi 《应用有机金属化学》2020,34(5):e5582
Reduced graphene oxide was synthesized and functionalized with FeSO4⋅7H2O to form a reduced graphene oxide/iron oxide hybrid composite. The hybrid composite was extensively characterized using various techniques. Its application for transfer hydrogenation of various ketones was studied. The investigation showed that it serves as a good catalyst for transfer hydrogenation of aromatic and some aliphatic ketones resulting in excellent isolated yields (97–99%) of products. It is magnetically separable showing good reusability. The products were characterized and compared with authentic ones. 相似文献
106.
Shakya Anshul Chaudhary Sushil Kumar Bhat Hans Raj Gogoi Neelutpal Ghosh Surajit Kumar 《平面色谱法杂志一现代薄层色谱法》2019,32(6):467-474
JPC – Journal of Planar Chromatography – Modern TLC - Ayurvedic medicines show great promise due to their holistic approach in the treatment of diseases. However, proper standardization... 相似文献
107.
A straightforward, efficient, and selective oxidation of sulfide to sulfoxide with 30% H2O2 catalyzed by copper(II)–Schiff base complex is described. The reactions proceed under mild conditions in acetonitrile at room temperature to provide a variety of aryl and alkyl sulfoxides in excellent yield. 相似文献
108.
We report an efficient, mild and convenient synthetic protocol for the C–S cross-coupling reaction of various aryl, benzyl, allyl chlorides and thiols using 5 mol % Nickel–Schiff base catalyst with NaOH as the base, in DMF at 70 °C. Using this protocol, we have shown that a variety of aryl sulfides can be synthesized in excellent yields from readily available organic chlorides and thiols. 相似文献
109.
Pallabi Saikia Partha Pratim KaishapRashmi Prakash Kommuri ShekarraoSanjib Gogoi Romesh C. Boruah 《Tetrahedron letters》2014
The preparation of steroid/nonsteroid fused 7-substituted pyrazolo[1,5-a]pyrimidines is described by a one-pot reaction of steroidal/nonsteroidal ketones, aromatic aldehydes and 3-amino-1H-pyrazoles/5-amino-1H-pyrazoles in the presence of potassium tert-butoxide in good yield under reflux condition in ethanol. 相似文献
110.
An efficient synthesis of 4-benzyl cinnolines from aryl phenylallylidene hydrazone is described. In this report aluminium chloride as a Lewis acid catalyst and toluene as a solvent are used for the synthesis. This method is expected to more advantageous than the other reported methods of synthesis of the cinnoline rings because of its low cost, better yield, and benign reaction conditions.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献