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Manoj Vanaraja Karthika Muthukrishnan Shanmugam Boomadevi Rakesh Kumar Karn Vijay Singh Pramod K. Singh 《Phase Transitions》2016,89(2):107-114
TiO2 thin film was fabricated by dip coating method using titanium IV chloride as precursor and sodium carboxymethyl cellulose as thickening as well as capping agent. Structural and morphological features of TiO2 thin film were characterized by X-ray diffractometer and field emission scanning electron microscope, respectively. Crystallinity of the film was confirmed with high-intensity peak at (101) plane, and its average crystallite size was found to be 28 nm. The ethanol-sensing properties of TiO2 thin film was studied by the chemiresistive method. Furthermore, various gases were tested in order to verify the selectivity of the sensor. Among the several gases, the fabricated TiO2 sensor showed very high selectivity towards ethanol at room temperature. 相似文献
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Jaime R. Blanton Tianniu Chen Jonathan B. Diminnie Hu Cai Zhongzhi Wu Liting Li Karn R. Sorasaenee Keith T. Quisenberry Hongjun Pan Chang-Sheng Wang Sai-Heung Choi Yun-Dong Wu Zhenyang Lin Ilia A. Guzei Arnold L. Rheingold Ziling Xue 《Journal of molecular catalysis. A, Chemical》2002,190(1-2):101-108
Alkylidene complexes (Me3SiCH2)3Ta(PMe3)=CHSiMe3 (1) and Me3SiCH2Ta(PMe3)2(=CHSiMe3)2 (3a) were found to react with phenylsilanes H2SiR′Ph (R′=Me, Ph) and (PhSiH2)2CH2 to give disilyl-substituted alkylidenes (Me3SiCH2)3Ta=C(SiMe3)(SiHR′Ph) (2) and novel metallasilacyclobutadiene and metalladisilacyclohexadiene complexes. Silyl-substituted alkylidene complex (ButCH2)2W(=O)[=C(But)(SiPh2But)] (5a) was prepared from the reaction of O2 with an equilibrium mixture (ButCH2)W(=CHBut)2(SiPh2But) (4b) (ButCH2)2W(CBut)(SiPh2But) (4a). Our recent studies of the preparation of these complexes and mechanistic pathways in the formation of these silyl-substituted alkylidene complexes are summarized. 相似文献
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Conversion enhancement of tubular fixed-bed reactor for Fischer-Tropsch synthesis using static mixer
Phavanee Narataruksa Sabaithip Tungkamani Karn Pana-Suppamassadu Phongsak Keeratiwintakorn Siriluck Nivitchanyong Piyapong Hunpinyo Hussanai Sukkathanyawat Prayut Jiamrittiwong Visarut Nopparat 《天然气化学杂志》2012,(4):435-444
Recently,Fischer-Tropsch synthesis(FTS) has become an interesting technology because of its potential role in producing biofuels via Biomassto-Liquids(BTL) processes.In Fischer-Tropsch(FT) section,biomass-derived syngas,mainly composed of a mixture of carbon monoxide(CO) and hydrogen(H2),is converted into various forms of hydrocarbon products over a catalyst at specified temperature and pressure.Fixed-bed reactors are typically used for these processes as conventional FT reactors.The fixed-bed or packed-bed type reactor has its drawbacks,which are heat transfer limitation,i.e.a hot spot problem involved highly exothermic characteristics of FT reaction,and mass transfer limitation due to the condensation of liquid hydrocarbon products occurred on catalyst surface.This work is initiated to develop a new chemical reactor design in which a better distribution of gaseous reactants and hydrocarbon products could be achieved,and led to higher throughput and conversion.The main goal of the research is the enhancement of a fixed-bed reactor,focusing on the application of KenicsTM static mixer insertion in the tubular packed-bed reactor.Two FTS experiments were carried out using two reactors i.e.,with and without static mixer insertion within catalytic beds.The modeled syngas used was a mixed gas composed of H2/CO in 2:1 molar ratio that was fed at the rate of 30mL(STP)min1(GHSV≈136mL g1 cat h1) into the fixed Ru supported aluminum catalyst bed of weight 13.3g.The reaction was carried out at 180℃ and atmospheric pressure continuously for 36h for both experiments.Both transient and steady-state conversions(in terms of time on stream) were reported.The results revealed that the steady-state CO conversion for the case using the static mixer was approximately 3.5 times higher than that of the case without static mixer.In both cases,the values of chain growth probability of hydrocarbon products(α) for Fischer-Tropsch synthesis were 0.92 and 0.89 for the case with and without static mixer,respectively. 相似文献
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Positivity - We characterize M-ideals in order smooth $$\infty $$-normed spaces by extending the notion of split faces of the state space to those of the quasi-state space. We also characterize... 相似文献
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Karinh E. J. Eurenius Henrik Karn?e Bentzer Nikolaos Bonanos Elisabet Ahlberg Christopher S. Knee 《Journal of Solid State Electrochemistry》2011,15(11-12):2571-2579
The results of concentration cell electromotive force methods (EMF) and electrochemical impedance spectroscopy measurements on the pyrochlore system Sm1.92Ca0.08Ti2O7?C?? are presented. The data have been used to estimate total and partial conductivities and determine transport numbers for protons and oxide ions under various conditions. The EMF techniques employed include corrections for electrode polarisation resistance. The measurements were performed using wet and dry atmospheres in a wide $ {p_{{{{\rm{O}}_{{2}}}}}} $ range using mixtures of H2, N2, O2, and H2O in the temperature region where proton conductivity was expected (500?C300?°C). The impedance measurements revealed the conductivity to be mainly ionic under all conditions, with the highest total conductivity measured being 0.045?S/m under wet oxygen at 500?°C. Both bulk and grain boundary conductivity was predominantly ionic, but electronic conductivity appeared to play a slightly larger part in the grain boundaries. EMF data confirmed the conductivity to be mainly ionic, with oxide ions being the major conducting species at 500?°C and protons becoming increasingly important below this temperature. 相似文献
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Anil Kumar Karn 《Positivity》2014,18(2):223-234
We introduce a notion of \(p\) -orthogonality in a general Banach space for \(1 \le p \le \infty \) . We use this concept to characterize \(\ell _p\) -spaces among Banach spaces and also among complete order smooth \(p\) -normed spaces as (ordered) Banach spaces with a total \(p\) -orthonormal set (in the positive cone). We further introduce a notion of \(p\) -orthogonal decomposition in order smooth \(p\) -normed spaces. We prove that if the \(\infty \) -orthogonal decomposition holds in an order smooth \(\infty \) -normed space, then the \(1\) -orthogonal decomposition holds in the dual space. We also give an example to show that the above said decomposition may not be unique. 相似文献
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An algorithm for reconstructing three dimensional images of coherent structures using a commercially available video image processing system is presented. The principal advantages of this work are low cost and minimal development time. The image processing system comes complete with frame grabbing and four software programs needed for image reconstruction. The process entails: grabbing individual video frames comprising a single three dimensional image of a vortex, converting each frame to a polygon, ordering successive polygons to reconstruct the vortex skeleton, and generating a surface for full three dimensional reconstruction. The processing system also includes a computer movie studio for creating animations, and a video editing system for producing professional quality video presentations.Support of the Office of Naval Research (Grant No. N00014-92-J-1020) through Dr. Edwin P. Rood is gratefully acknowledged. 相似文献
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S.K. Karn R.S. Kaushal Y.K. Mathur 《The European Physical Journal C - Particles and Fields》2000,14(3):487-494
Within the framework of an effective -theory, an attempt is made to study diquark stars and their stability with extended scalar diquarks (ESD). In this context,
an equation of state (EOS) for the ESD gas is obtained. We find the EOS for the ESD gas to be stiffer than that for a point-like
diquark and/or quark gas. This EOS is then used to investigate various properties of the diquark stars. In particular, the
mass and radius of the maximum mass star with ESD matter turn out to be larger than those obtained with point-like diquark
and/or quark matter. However, they are in conformity with the predictions available for soliton and boson stars. The stability
of ESD stars against radial oscillations is also investigated.
Received: 18 May 1999 / Revised version: 19 November 1999 / Published online: 14 April 2000 相似文献