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Catalytic oxidative desulfurization of gasoline using phosphotungstic acid supported on MWW zeolite

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 546-560页

作者： Hanlu Wang idris Jibrin Xingye Zeng College of Chemical Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China

Catalysts for the desulfurization of gasoline samples were synthesized via the immobilization of well-dispersed phosphotungstic acid(HPW)on Mobil compo-sition of matter-twenty-two(MWW)***-tion results indicated that these catalysts possess a mesoporous structure with the retention of the Keggin structure of immobilized *** reaction para-meters influencing sulfur removal were systematically investigated,including HPW loading,catalyst dosage,temperature,initial S-concentration,molar ratio of oxidant to sulfide(O/S),volume ratio of MeCN to model oil(Ext./oil),and sulfide *** 40 wt-%HPW/MWW catalyst exhibited the highest catalytic activity with 99.6%dibenzothiophene sulfur removal from prepared *** 40 wt-%HPW/MWW catalyst was recycled four times and could be easily ***,as an exploratory study,straight-run-gasoline and fluid catalytic cracking gasoline were employed to accurately evaluate the desulfurization performance of 40 wt-%HPW/*** research provides new insights into the development and application of catalysts for desulfurization of gasoline.

关键词： oxidative desulfurization phosphotungstic acid MWW wet impregnation adsorption energy

Wavelet Based Image Authentication and Recovery

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Journal of Computer Science & Technology 2007年第6期22卷 795-804页

作者： Rafiullah Chamlaw Asifullah Khan Adnan idris Pakistan Institute of Engineering and Applied Sciences (PLEAS) NiloreIslamabadPakistan A JK University RawalakotAzad Jammu and Kashmir(AJK)Pakistan

In this paper, we propose a secure semi-fragile watermarking technique based on integer wavelet transform with a choice of two watermarks to be embedded. A self-recovering algorithm is employed, that hides the image digest into some wavelet subbands for detecting possible illicit object manipulation undergone in the image. The semi-fragility makes the scheme tolerant against JPEG lossy compression with the quality factor as low as 70%, and locates the tampered area accurately. In addition, the system ensures more security because the embedded watermarks are protected with private keys. The computational complexity is reduced by using parameterized integer wavelet transform. Experimental results show that the proposed scheme guarantees safety of a watermark, recovery of image and localization of tampered area.

关键词： semi-fragile watermark integer wavelet transform (IWT) discrete cosine transform (DCT) JPEG compression authentication and self-recovery

Performance analysis of empirical models for predicting rock mass deformation modulus using regression and Bayesian methods

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第6期12卷 1263-1271页

作者： Adeyemi Emman Aladejare Musa Adebayo idris Oulu Mining School University of OuluOuluFinland Division of Mining and Geotechnical Engineering Department of CivilEnvironmental and Natural Resources EngineeringLuleåUniversity of TechnologyLuleåSweden

Deformation modulus of rock mass is one of the input parameters to most rock engineering designs and *** field tests for determination of deformation modulus are cumbersome,expensive and *** has prompted the development of various regression equations to estimate deformation modulus from results of rock mass classifications,with rock mass rating(RMR)being one of the frequently used *** regression equations are of different types ranging from linear to nonlinear functions like power and *** method has recently been developed to incorporate regression equations into a Bayesian framework to provide better estimates of geotechnical *** question of whether Bayesian method improves the estimation of geotechnical properties in all circumstances remains ***,a comparative study was conducted to assess the performances of regression and Bayesian methods when they are used to characterize deformation modulus from the same set of RMR data obtained from two project *** study also investigated the performance of different types of regression equations in estimation of the deformation ***,probability distributions and prediction indicators were used to assess the performances of regression and Bayesian methods and different types of regression *** was found that power and exponential types of regression equations provide a better estimate than linear regression *** addition,it was discovered that the ability of the Bayesian method to provide better estimates of deformation modulus than regression method depends on the quality and quantity of input data as well as the type of the regression equation.

关键词： Deformation modulus Rock mass Regression equation Bayesian method Performance analysis Rock mass rating(RMR)

Phytochemical Estimation and Therapeutic Amelioration of Aesculus hippocastanum L. Seeds Ethanolic Extract in Gastric Ulcer in Rats Possibly by Inhibiting Prostaglandin Synthesis

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Chinese Journal of Integrative Medicine 2023年第9期29卷 818-824页

作者： Sahar idris Anuradha Mishra Mohammad Khushtar Faculty of Pharmacy Integral UniversityDasauliLucknow226026Uttar PradeshIndia Amity Institute of Pharmacy LucknowAmity University Uttar PradeshNoida201313India

Objective To quantify phytochemicals using liquid chromatography and mass spectroscopy(LCMS)analysis and explore the therapeutic effect of Aesculus hippocastanum L.(AH)seeds ethanolic extract against gastric ulcers in *** Preliminary phytochemical testing and LCMS analysis were performed according to standard *** treatment,the animals were divided into 7 groups including normal control,ulcer control,self-healing,AH seeds low and high doses,ranitidine and per se *** were orally administered with 10 mg/kg of indomethacin,excluding the normal control group(which received 1%carboxy methyl cellulose)and the per se group(received 200 mg/kg AH seeds extract).The test group rats were then given 2 doses of AH seeds extract(100 and 200 mg/kg,respectively),while the standard group was given ranitidine(50 mg/kg).On the 11th day,rats in all groups were sacrificed,and their stomach was isolated to calculate the ulcer index,and other parameters such as blood prostaglandin(PGE2),tissue superoxide dismutase(SOD),catalase(CAT),malonyldialdehyde(MDA),and glutathione(GSH).All isolated stomach tissues were analyzed for histopathological *** The phytochemical examination shows that the AH seeds contain alkaloids,flavonoids,saponins,phenolic components,and *** analysis confirms the presence of quercetin and *** AH seeds extract showed significant improvement in gastric mucosa conditions after indomethacin-induced gastric lesions(P<0.01).Further marked improvement in blood PGE2 and antioxidant enzymes,SOD,CAT,MDA and GSH,were observed compared with self-healing and untreated ulcer-induced groups(P<0.01).Histopathology results confirmed that AH seeds extract improved the mucosal layer and gastric epithelial membrane in treated groups compared to untreated ulcer-induced *** LCMS report confirms the presence of quercetin and rutin in AH seeds ethanolic *** therapeutic effect of AH seeds extract against indomethacin

关键词： Aesculus hippocastanum L. pharmacological action phytochemical physicochemical analysis liquid chromatography and mass spectroscopy analysis gastro-protective activity

Simulations of solitary waves of RLW equation by exponential B-spline Galerkin method

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Chinese Physics B 2017年第8期26卷 24-31页

作者： Melis Zorsahin Gorgulu idris Dag Dursun Irk Department of Mathematics-Computer Eskisehir Osmangazi University26480EskisehirTurkey Department of Computer Engineering Eskisehir Osmangazi University26480EskisehirTurkey

In this paper, an approximate function for the Galerkin method is composed using the combination of the exponential B-spline functions. Regularized long wave equation （RLW） is integrated fully by using an exponential B-spline Galerkin method in space together with Crank-Nicolson method in time. Three numerical examples related to propagation of sin- gle solitary wave, interaction of two solitary waves and wave generation are employed to illustrate the accuracy and the efficiency of the method. Obtained results are compared with some early studies.

关键词： solitary waves exponential B-spline Galerkin method RLW equation

Analysis of the changes in forest ecosystem functions,structure and composition in the Black Sea region of Turkey

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Journal of Forestry Research 2017年第2期28卷 329-342页

作者： Sedat Keles idris Durusoy Günay Cakir Faculty of Forestry Cankin Karatekin University18100 CankinTurkey Faculty of Forestry Duzce University81620 DuzceTurkey Department of Forestry and Environmental Science Graduate School of Natural and Applied SciencesGumushane University29100 GumushaneTurkey

We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability： economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types,tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas（especially in settlement and agricultural areas）, forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.

关键词： ecosystem forests timber stand biomass stock favorable closure rehabilitation Turkey

Mechanical properties of stabilized zirconia nanocrystalline EB-PVD coating evaluated by micro and nano indentation

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Journal of Advanced Ceramics 2013年第4期2卷 333-340页

作者： Meysam KESHAVARZ Mohd Hasbullah idris Norhayati AHMAD Department of Materials Science and Engineering Faculty of Mechanical EngineeringUniversiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia

Yttria-stabilized zirconia(YSZ)thin nanocrystalline coatings at different substrate preheating temperatures were deposited via electron beam-physical vapour deposition(EB-PVD).Nanocrystalline ZrO_(2)-Y_(2)O_(3) was deposited on the bond coat in order to compensate for the coefficient of thermal expansion(CTE),which can be functionalized as a thermal barrier coating(TBC).The aim of this study was to evaluate mechanical properties with respect to adhesion of zirconia nanocrystalline’s top ceramic layer to the interfacial bond coat by utilizing micro and nano indentation *** the present paper,the structural studies were carried out using X-ray diffraction(XRD)analysis of coating content(8 mol%of Y_(2)O_(3)).The tetragonal phase of stabilized zirconia was *** emission scanning electron microscopy(FESEM)and atomic force microscopy(AFM)were employed to characterize the coatings’morphology and *** mechanical behavior of ZrO_(2)-Y_(2)O_(3) thin films under point loading conditions was studied by nanoindentation using a Berkovich indenter with 130 nm tip ***,adhesion of top coat to the interfacial underlying metallic bond coat known as MCrAlY(M=Ni,Co)was estimated according to the highest peak load tests;for a 120 mN peak load,the film manifested tolerable adhesion ***,nanoindentation of ZrO_(2)-Y_(2)O_(3) nanostructure deposited at 1050℃substrate preheating temperature produced the highest hardness value of about 21.7 *** micro hardness was utilized with the aid of the Tabor equation in order to achieve deeper insight into the correlation between adhesion and deposition process parameters.

关键词： zirconia nanoindentation nanocrystalline electron beam-physical vapour deposition(EB-PVD) thermal barrier coating(TBC)

Effect of Fe_2O_3/SiO_2 ratio on maghemite-silica particulate nanocomposites

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Journal of Central South University 2013年第11期20卷 2954-2959页

作者： ANG Bee Chin YAACOB Iskandar idris NURDIN Irwan Department of Mechanical University of Malaya Department of Manufacturing and Materials Engineering Kulliyyah of EngineeringInternational Islamic University Malaysia

Abstract： Maghemite-silica particulate nanocomposites were prepared by modified 2-step sol-gel process. Superparamagnetic maghemite nanoparticles were successfully produced using Massart＇s procedure. Nanocomposites consisting of synthesized maghemite nanoparticles and silica were produced by dispersing the as-synthesized maghemite nanoparticles into the silica particulate form. The system was then heated at 140 ℃for 3 d. A variety of mass ratios of Fe2O3/SiO2 was investigated. Moreover, no surfactant or other unnecessary precursor was involved. The nanocomposites were characterized using XRD, BET and AGM. The XRD diffraction patterns show the reflection corresponding to maghemite nanoparticles and a visible wide band at 20 from 20° to 35° which are the characteristics of the amorphous phase of the silica gel. The patterns also exhibit the presence of only maghemite and SiO2 amorphous phase, which indicates that there is no chemical reaction between the silica particulate gel and maghemite nanoparticles to form other compounds. The calculated crystallite size for encapsulated maghemite nanoparticles is smaller than the as-synthesized maghemite nanoparticles indicating the dissolution of the nanoparticles. Very high surface area is attained for the produced nanocomposites （360-390 m^2/g）. This enhances the sensitivity and the reactivity of the nanocomposites. The shapes of the magnetization curves for nanocomposites are very similar to the as-synthesized maghemite nanoparticles. Superparamagnetic behaviour is exhibited by all samples, indicating that the size of the maghemite nanoparticles is always within the nanometre range. The increase in iron content gives rise to a small particle growth.

关键词： maghemite nanoparticles nanocomposites sol-gel silica

Kinetic degradation of amoxicillin by using the electro-Fenton process in the presence of a graphite rods from used batteries

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Chinese Journal of Chemical Engineering 2021年第4期34卷 183-190页

作者： Hakima Kadji idris Yahiaoui Zehira Garti Abdeltif Amrane Farida Aissani-Benissad Laboratoire de Genie de l'Environnement(LGE) Faculte de TechnologieUniversite de Bejaia06000 BejaiaAlgeria Ecole Nationale Superieure de Chimie de Rennes Universite RenneslCNRSUMR 622611 allee de BeaulieuCS 50837France

This study reports the removal of amoxicillin(AMX)in aqueous media using the electroFenton process in the presence of a graphite cathode recovered from used *** impact of the relevant parameters on the electroFenton process,namely the applied current intensity,the temperature,the initial concentration of AMX and the initial concentration of ferrous ions were *** results showed that the optimal values were:I=600 mA,T=25℃,[AMX]_(0)=0.082 mmol·L^( 1) and[Fe^(2+)]=1 mmol·L^(1),leading to 95%degradation and 74%*** model parameters of AMX mineralization were determined using nonlinear methods,showing that it follows a pseudosecondorder *** Energy consumption(EC)calculated under the optimal values was found to be 0.79 kWhg 1,which was of the same order of magnitude of those reported in other findings;while it is noteworthy that the electrodes used in our study are of a lower cost.

关键词： Wastewater Amoxicillin Electro-Fenton Pharmaceuticals Solid waste recovery Kinetic modelling