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Enhanced acetone sensing performance of nanostructured Sm2O3 doped SnO2 thick films

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Journal of Rare Earths 2017年第8期35卷 813-823页

作者： F.i.Shaikh L.p.Chikhale J.Y.patil i.S.Mulla S.S.Suryavanshi School of physical Sciences Solapur University Solapur 413255 (M.S.) lndia Council of Scientific and industrial Research Pashan Pune 411008 India

in the present work, we synthesized Sm2O3 doped SnO2 in order to prepare a selective acetone sensor with fast response, quick recovery and good repeatability. pure as well as 2 mol.%, 4 mol.%, 6 mol.% and 8 mol.% Sm2O3 doped SnO2 nanostructured samples were synthesized by using a co-precipitation method. The characterization of the samples was done by thermogravimetric and differential thermo-gravimetric analysis（TG-DTA）, X-ray diffraction（XRD）, field emission gun-scanning electron microscopy（FEG-SEM）, energy dispersive analysis by X-rays（EDAX）, high resolution scanning electron microscopy（HR-TEM）, selected area X-ray diffraction（SAED）, Brunauer-Emmet-Teller（BET） and ultraviolet-visible-near infrared（UV-Vis-NiR） spectroscopy techniques. The gas response studies of liquid petroleum gas, ammonia, ethanol and acetone vapor were carried out. The results showed that Sm doping systematically lowered operating temperature and enhanced the gas response and selectivity for acetone. The response and recovery time for 6 mol.% Sm2O3 doped SnO2 thick film at the operating temperature of 250 °C were 15 and 24 s, respectively.

关键词： tin oxide samarium oxide screen printing thick film acetone sensor rare earths

Acute colonic pseudo-obstruction: A systematic review of aetiology and mechanisms

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World Journal of Gastroenterology 2017年第30期23卷 5634-5644页

作者： Cameron i Wells Gregory O’Grady ian p Bissett Department of Surgery University of Auckland Department of Surgery Auckland District Health Board

To critically review the literature addressing the definition, epidemiology, aetiology and pathophysiology of acute colonic pseudo-obstruction (ACpO). METHODSA systematic search was performed to identify articles investigating the aetiology and pathophysiology of ACpO. A narrative synthesis of the evidence was undertaken. RESULTSNo consistent approach to the definition or reporting of ACpO has been developed, which has led to overlapping investigation with other conditions. A vast array of risk factors has been identified, supporting a multifactorial aetiology. The pathophysiological mechanisms remain unclear, but are likely related to altered autonomic regulation of colonic motility, in the setting of other predisposing factors. CONCLUSiONFuture research should aim to establish a clear and consistent definition of ACpO, and elucidate the pathophysiological mechanisms leading to altered colonic function. An improved understanding of the aetiology of ACpO may facilitate the development of targeted strategies for its prevention and treatment.

关键词： Acute colonic pseudoobstruction Acute colonic pseudo-obstruction Colonic intestinal pseudo obstruction Ogilvie’s syndrome pseudo-Obstruction pseudo-Obstruction

Modern diagnostic approaches to cholangiocarcinoma

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Hepatobiliary & pancreatic Diseases international 2012年第4期11卷 349-359页

作者： Larisa E Vasilieva Stefanos i papadhimitriou Spyros p Dourakis Second Department of internal Medicine University of Athens Medical SchoolHippokration General Hospital114 Vas Sofias AvenueAthens 11527Greece Molecular Cytogenetics Unit Haematology Laboratory"G.Genimatas" Regional General HospitalAthensGreece

BACKGROUND:Cholangiocarcinoma is a very aggressive tumor with poor ***,early diagnosis and surgical resection are of paramount *** diagnosis is difficult because access to the tumor is not *** is possible only for intrahepatic cholangiocarcinoma,which accounts for 10% of *** brush cytology from endoscopic retrograde cholangiopancreatography(ERCp) has a high specificity of 100% but unfortunately a low sensitivity of 30%.in this review we briefly describe new diagnostic techniques applicable to ERCp brush cytology specimens and targeting the genetic background of the disease,in particular fluorescence in situ hybridization(FiSH) and digital image analysis(DiA).DATE SOURCES:The pubMed database up to 2011 was used for the retrieval of relevant *** search terms FiSH,fluorescence in situ hybridization,DiA,digital image analysis and cholangiocarcinoma were *** original and review articles were ***:FiSH identifies cells with chromosomal abnormalities,mainly numerical aberrations,using a mixture of fluorescencelabeled *** offers a higher sensitivity than routine cytology,retaining a high level of *** DiA criterion for malignancy is demonstration of *** technique increases the sensitivity to 40%,but the specificity remains *** data from application to other tumors suggest that combination of FiSH and DiA may be of further ***:The new techniques offer a significantly enhanced diagnostic efficacy in the evaluation of ERCp brush *** from contributing to a more timely diagnosis,their wider application to cholangiocarcinoma may also facilitate the genetic study of the disease and add to our understanding of oncogenesis at the molecular level,with the prospect of identifying targets for novel therapeutic interventions.

关键词： cholangiocarcinoma fluorescence in situ hybridization digital image analysis

plasticity,strength,permeability and compressibility characteristics of black cotton soil stabilized with precipitated silica

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Journal of Central South University 2016年第10期23卷 2688-2694页

作者： R.Gobinath G.p.Ganapathy i.i.Akinwumi S.Kovendiran S.Hema M.Thangaraj ViT University VelloreIndia Department of Civil Engineering Jay Shriram Group of InstitutionsTiruppurIndia Centre for Disaster Mitigation and Management VIT UniversityVelloreIndia Department of Civil Engineering College of EngineeringCovenant UniversityOtaOgun StateNigeria

The suitability of using precipitated silica(pS) from the burning of rice husk was investigated to improve the geotechnical engineering properties of a black cotton soil. A laboratory experimental program consisting of series of specific gravity, Atterberg limits, compaction, California bearing ratio(CBR), unconfined compression and consolidation tests was conducted on the untreated and pS treated soil samples. The application of pS to the soil significantly changed its properties by reducing its plasticity and making it more workable, improving its soaked strength, and increasing its permeability and the rate at which the soil gets consolidated. An optimal pS content of 50%, which provided the highest soaked strength, is recommended for the improvement of the subgrade characteristics of the BC soil for use as a pavement layer material.

关键词： black cotton soil expansive soil precipitated silica rice husk ash soil stabilization

iMpROVED TABU SEARCH RECURSiVE FUZZY METHOD FOR CRUDE OiL iNDUSTRY

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international Journal of Modeling, Simulation, and Scientific Computing 2012年第1期3卷 31-50页

作者： p.VASANT T.GANESAN i.ELAMVAZUTHi Fundamental and Applied Sciences Department University Technology pETRONAS 31750 TronohMalaysia Mechanical Engineering Department University Technology pETRONAS 31750 TronohMalaysia Electrical and Electronics Engineering Department University Technology pETRONAS 31750 TronohMalaysia

The minimization of the profit function with respect to the decision variables is very important for the decision makers in the oil field *** this paper,a novel approach of the improved tabu search algorithm has been employed to solve a large scale problem in the crude oil refinery *** problem involves 44 variables,36 constraints,and four decision variables which represent four types of crude oil *** decision variables have been modeled in the form of fuzzy linear programming *** vagueness factor in the decision variables is captured by the nonlinear modified S-curve membership function.A recursive improved tabu search has been used to solve this fuzzy optimization *** improved results are obtained for the optimal profit function and optimal solution for four crude *** accuracy of constraints satisfaction and the quality of the solutions are achieved successfully.

关键词： Crude oil membership function improved tabu search recursive technique level of satisfaction

On the pressure and stress singularities induced by steady flows of incompressible viscous fluids

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Acta Mechanica Sinica 2009年第4期25卷 451-462页

作者： G.B.Sinclair X.Chi T.i-p.Shih Department of Mechanical Engineering Louisiana State University Department of Aerospace Engineering Iowa State University

Design for structural integrity requires an appreciation of where stress singularities can occur in structural configurations. While there is a rich literature devoted to the identification of such singular behavior in solid mechanics, to date there has been relatively little explicit identification of stress singularities caused by fluid flows. in this study, stress and pressure singularities induced by steady flows of viscous incompressible fluids are asymptotically identified. This is done by taking advantage of an earlier result that the Navier-Stokes equations are locally governed by Stokes flow in angular corners. Findings for power singularities are confirmed by developing and using an analogy with solid mechanics. This analogy also facilitates the identification of flow-induced log singularities. Both types of singularity are further confirmed for two global configurations by applying convergence-divergence checks to numerical results. Even though these flow-induced stress singularities are analogous to singularities in solid mechanics, they nonetheless render a number of structural configurations singular that were not previously appreciated as such from identifications within solid mechanics alone.

关键词： incompressible viscous fluids Navier-Stokes equations Fluid-structure interactions Stress singularities

Geomorphological monitoring of a highly dynamic estuary using oblique aerial photographs

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international Journal of Digital Earth 2009年第2期2卷 109-121页

作者： i.Abou El-Magd p.F.Hillman National Authority for remote sensing and Space Sciences CairoEgypt Gifford Carlton HaneSouthamptonUK588 Booth Street OttawaOntarioCanada

Bad weather in many countries limits the use of optical satellite imageries in spatial and temporal monitoring of the *** this paper,a series of lowaltitude oblique aerial photos taken on daily,weekly and monthly intervals were used to monitor the geomorphological changes in the upper part of the Mersey Estuary,northwestern *** low-altitude aerial photo methodology reveals itself to be a satisfying compromise between cost,accuracy and difficulty of *** offered a large amount of information on a spatial and temporal scale aiding in the understanding of channel *** was an important consideration in the sitting and installation of new bridge pier *** series of oblique aerial photos was used in a dynamic model to determine the migration of the ebb channel and was effective in identifying the main route of *** uncertainties were encountered and the level of accuracy achieved in resolving these uncertainties in the images was in the range from 40 cm to a maximum of 1.7 *** was compared with historical navigation charts and showed good *** applications are required to improve the quality of the data output from these images and the development of the technique.

关键词： geomorphology estuary GiS modelling oblique aerial photography,UK

NSVS 2569022:a peculiar binary among W UMa stars with extremely small mass ratios

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Research in Astronomy and Astrophysics 2018年第10期18卷 123-130页

作者： Diana p.Kjurkchieva Velimir A.popov Nikola i.petrov Department of physics and Astronomy Shumen University institute of Astronomy and NAO Bulgarian Academy of Sciences

photometric observations of the W UMa binary NSVS 2569022 are presented. The light curve solution reveals that both components are of F spectral type （temperatures T1 = T2 = 6100 K）. NSVS 2569022 undergoes a total eclipse of W subtype and the mass ratio is well-determined. its extremely small value of only 0.077 implies that the target will probably experience instability and a possible merger. This value ranks NSVS 2569022 in sixth place among binaries with the smallest mass ratio. Based on an empirical relation of ＂period - total mass＂ for low mass-ratio binaries, we estimate the global parameters of NSVS 2569022： masses M1 = 1.17 M⊙ and M2 = 0.09 M⊙; radii R1 = 1.19 R⊙ and R2 = 0.38 R⊙; luminosities L1 = 1.73 L⊙ and L2 = 0.17L⊙. An analysis of the characteristics of binaries with extremely low-mass ratios is made. NSVS 2569022 turns out to be a peculiar binary among W UMa stars with extremely small mass ratios due to its unexpectedly small fill-out factor of only 0.014 （slightly overcontact configuration）.

关键词： binaries eclipsing - binaries close - stars fundamental parameters - stars individual(NSVS 2569022)

New observations and transit solutions of the inflated exoplanets HAT-p-40b and HAT-p-51b

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Research in Astronomy and Astrophysics 2021年第2期21卷 157-160页

作者： Diana p.Kjurkchieva Nikola i.petrov Velimir A.popov Department of physics and Astronomy Shumen University115 Universitetska str.9700 ShumenBulgaria institute of Astronomy and NAO Bulgarian Academy of SciencesTsarigradsko shossee 721784 SofiaBulgaria

We present high-precision photometric observations of the transiting exoplanets HAT-p-40 b and HAT-p-51 b by the Rozhen 2-m *** newly-observed transit of HAT-p-40 b is the first one with a complete *** orbital periods of the two targets were *** modeled the observed transits and found bigger stellar radii than those derived from the stellar *** planet radii of HATp-40 b and HAT-p-51 b obtained from our transit solutions are bigger than the values calculated by the empirical relations for Jupiter-mass and Saturn-mass planets *** values reveal the highlyinflated nature of the two targets,especially that of HAT-p-51 *** established that the best transit solutions correspond to a quadratic limb-darkening *** fitted limb-darkening coefficients of HAT-p-40 are close to the theoretical ones while those of HAT-p-51 are a little *** precise astrometric Gaia distances of the two targets are smaller by 6%–7%than the calculated values from the stellar *** propose the Gaia distances to be used for improvement of the stellar models as well as for more reliable calculation of the parameters of the known exoplanets.

关键词： (Stars )planetary systems-techniques photometric-Stars individual(HAT-p-40 and HAT-p-51)