检索结果-南通市图书馆

Journal of Rare Earths 2013年第5期31卷 477-484页

作者： Azhagapillai Prabhu Ahmed Al Shoaibi Chandrasekar Srinivasakannan Muthaiahpillai Palanichamy velayutham murugesan Department of Chemical Engineering The Petroleum InstituteAbu DhabiUAE Department of Chemistry Anna University

Cerium incorporated KIT-6 mesoporous materials were synthesized through direct hydrothermal method and characterized by using X-ray diffraction （XRD）, nitrogen sorption isotherm （BET）, Fourier transform infrared spectroscopy （FT-IR）, inductively coupled plasma - atomic emission spectroscopy （ICP-AES）, diffuse reflectance ultraviolet visible spectroscopy （DRS-UV-Vis）, ther- mogravimetric analysis （TGA）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM） methods. It ap- peared that stable cerium ions were inserted into the silica framework of KIT-6, thus generating acid properties in their host materials. The catalytic activity of Ce-KIT-6 materials was evaluated in the vapor phase dehydration of cyclohexanol to cyclohexene and dicy- clohexyl ether at different temperatures with various Si/Ce molar ratios. Ce-KIT-6 （25） showed higher activity with 54% cyclohexa- nol conversion and 64% selectivity to cyclohexene. The catalytic results indicated that Ce-KIT-6 mesoporous materials could be used as versatile and stable acid catalysts.

关键词： Ce-KIT-6 dehydration eyclohexanol cyclohexene dicyclohexyl ether rare earths

CeAlPO-5分子筛催化剂上二苯基甲烷选择性氧化生成二苯甲酮(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2012年第7期33卷 1086-1094页

作者： Subbiah DEVIKA Muthiahpillai PALANICHAMY velayutham murugesan Department of Chemistry Anna University

Selective oxidation of diphenylmethane to benzophenone requires active and selective catalysts. The framework incorporation of cerium in AlPO-5 molecular sieves creates active cerium sites in isolation. These active sites are responsible for selective oxidation. Cerium incorporated AlPO-5 with different Al/Ce ratios were synthesized, and the vapor phase oxidation of diphenylmethane in air over these catalysts was studied at 250, 275, 300, 325, and 350 °C. The diphenylmethane conversion and selectivity for benzophenone were more than 90%. CeAlPO-5(25) was found to be more active than other catalysts. The stability of the catalyst was verified by the time on stream study which indicated steady diphenylmethane conversion and benzophenone selectivity. Hence framework incorporated CeAlPO-5 molecular sieves are stable and active catalysts for the selective oxidation of diphenylmethane.

关键词： CeAlPO-5 molecular sieve hydrothermal synthesis oxidation diphenylmethane benzophenone

Al-MCM-48分子筛对苯酚与乙酸异丙酯异丙基化反应的催化性能(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2012年第3期33卷 478-486页

作者： Kandan VENKATACHALAM Pitchai VISUVAMITHIRAN Balachandran SUNDARAVEL Muthiapillai PALANICHAMY velayutham murugesan Department of Chemistry Anna University

Al-MCM-48 molecular sieves (Si/Al molar ratios = 25, 50, 75, and 100) were synthesized hydrothermally using cetyltrimethyl-ammonium bromide as the structure directing template. The orderly arrangement of mesopores was evident from the low angle X-ray diffraction patterns and transmission electron microscopy images. The catalytic performance of the materials was evaluated in the vapor phase isopropylation of phenol with isopropyl acetate. Phenol conversion decreased with the increase in the Si/Al ratio of the catalysts. The major reaction product was 4-isopropyl phenol with 78% selectivity. The delocalization of phenolic oxygen electron pair over the aromatic ring promoted para-selective alkylation. Such delocalization could be aided by the hydrophilic surface of the molecular sieves. Although an ester was used as the alkylating agent, phenyl isopropyl ether was not formed in the reaction.

关键词： MCM-48分子筛异丙基苯酚醋酸异丙酯催化性能十六烷基三甲基溴化铵透射电子显微镜反应产物水热法合成

ZSM-5沸石结晶度对乙苯叔丁基化对位选择性的影响(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2013年第2期34卷 294-304页

作者： PUSHPARAJ Hemalatha MANI Ganesh MUTHIAHPILLAI Palanichamy velayutham murugesan PARK Yong-Ki CHOI Won Choon JANG Hyun Tae Department of Chemical Engineering Hanseo University Seosan-si 356 706 South Korea Department of Chemistry Anna University Chennai 600 025 India Green Chemistry Research Division Korea Research Institute of Chemical Technology Jang-dong 100. Daejeon 305 600 South Korea

Highly crystalline ZSM-5 zeolites are important for para-selective alkylation of alkyl aromatics, because they carry few external acid sites for isomerization of p-dialkyl products. Such zeolites (Si/Al = 25, 50, and 75) were synthesized in a fluoride medium between pH 4 and 6. Their crystallinities, crystal sizes, and surface areas were higher than those of a commercial ZSM-5 zeolite. Their para selectivities in alkylation were tested for vapor-phase tert-butylation of ethylbenzene between 200 and 400 °C. As expected, all the catalysts showed more than 90% para selectivity. At 300 °C, ethylbenzene conversion decreased in the order ZSM-5(25, commercial) > ZSM-5(25) > ZSM-5(50) > ZSM-5(75). The catalysts had weak, medium, and strong acid sites, but all the acid sites of ZSM-5(75) were weaker than those of ZSM-5(25) and ZSM-5(50). The high activity of commercial ZSM-5 was caused by its strong acid sites being stronger than those of the synthesized zeolites. Although the activity of the commercial catalyst was higher than those of the present catalysts, the selectivity for 4-t-butylethylbenzene (4-t-BEB) was low. The optimum feed ratio (ethylbenzene:t-butyl alcohol) was 2:1 and the feed rate was 1.65 h?1 for high ethylbenzene conversion and 4-t-BEB selectivity. Time-on-stream studies showed slow catalyst deactivation. Highly crystalline ZSM-5 zeolites are therefore better than a commercial zeolite for para-selective alkylation of alkyl aromatics. They do not require much post-modification for high para selectivity. A fluoride medium is therefore better than an alkaline medium for obtaining highly crystalline para-selective ZSM-5 zeolites.

关键词： ZSM-5 Fluoride medium P-selectivity Ethylbenzene Tert-butylation Zeolite

Cellular interplay to 3D in vitro microphysiological disease model:cell patterning microbiota-gut-brain axis

在线全文

学校读者我要写书评

暂无评论

Bio-Design and Manufacturing 2024年第3期7卷 320-357页

作者： Kamare Alam Lakshmi Nair Souvik Mukherjee Kulwinder Kaur Manjari Singh Santanu Kaity velayutham Ravichandiran Sugato Banerjee Subhadeep Roy Department of Pharmacology and Toxicology National Institute of Pharmaceutical Education and ResearchKolkataWest Bengal 700054India Department of Pharmaceutical Sciences Assam UniversitySilchar 788011India Department of Pharmaceutical Sciences Guru Ghasidas UniversityKoniBilaspur 495009C.G.India School of Pharmacy and Biomolecular Sciences RCSI University of Medicine and Health SciencesDublin D02 YN77Ireland Tissue Engineering Research Group Department of Anatomy and Regenerative MedicineRCSI University of Medicine and Health SciencesDublin D02 YN77Ireland Department of Pharmaceutics National Institute of Pharmaceutical Education and ResearchKolkataWest Bengal 700054India Department of Natural Products National Institute of Pharmaceutical Education and ResearchKolkataWest Bengal 700054India

The microbiota-gut-brain axis(MGBA)has emerged as a key prospect in the bidirectional communication between two major organ systems:the brain and the *** between the two organ systems allows the body to function without disease,whereas dysbiosis has long-standing evidence of etiopathological *** most common communication paths are the microbial release of metabolites,soluble neurotransmitters,and immune ***,each pathway is intertwined with a complex *** the emergence of in vitro models and the popularity of three-dimensional(3D)cultures and Transwells,engineering has become easier for the scientific understanding of neurodegenerative *** paper briefly retraces the possible communication pathways between the gut microbiome and the *** further elaborates on three major diseases:autism spectrum disorder,Parkinson’s disease,and Alzheimer’s disease,which are prevalent in children and the *** diseases also decrease patients’quality of ***,understanding them more deeply with respect to current advances in in vitro modeling is crucial for understanding the *** of MGBA in the laboratory uses many molecular technologies and biomaterial *** and organoids provide a more realistic picture of the cell and tissue structure than *** them with the Transwell system offers the advantage of compartmentalizing the two systems(apical and basal)while allowing physical and chemical cues between ***-edge technologies,such as bioprinting and microfluidic chips,might be the future of in vitro modeling,as they provide dynamicity.

关键词： Microbiota-gut-brain axis Neurodegeneration 3D disease model Organoid Transwell system

Impact of nanoparticle shape on thermo-solutal buoyancy induced lid-driven-cavity with inclined magnetic-field

在线全文

学校读者我要写书评

暂无评论

Propulsion and Power Research 2022年第1期11卷 97-117页

作者： Ratnadeep Nath Krishnan murugesan Department of Mechanical and Industrial Engineering Indian Institute of Technology RoorkeeRoorkee247667India

The aim of this paper is to numerically investigate the influence of nanoparticles shape on heat and mass transport phenomena in a moving lid cavity under the combined effect of thermo-solutal buoyancy force and magnetic *** governing equations are transformed into velocity-vorticity form of equations and solved using Galerkin's weighted residual *** analysis has been carried out with parameters like buoyancy ratio(−5≤N≤5),magnetic field inclination angle(0°≤ϕ≤90°)with four shapes of Al_(2)O_(3) nanoparticle like bricks,blades,platelets and *** results revealed that the shape factor on Nusselt number is significant depending upon the inclined magnetic field and buoyancy ratio whereas on mass transfer the shape effect is *** diffusion mode of transport process is stronger than the convection mode at higher inclination angle of magnetic *** on a given value of N andϕ,blade and cylinder shows the best performance in Nusselt and Sherwood number respectively except the platelet shape that shows maximum frictional loss in terms of wall shear stress.

关键词： Velocity-vorticity formulation Thermo-solutal buoyancy forces Nanofluid Shapes of nanoparticles Inclined magnetic field

Indocyanine green fluorescence in gastrointestinal surgery:Appraisal of current evidence

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2023年第12期15卷 2693-2708页

作者： Raja Kalayarasan murugesan Chandrasekar Pothugunta Sai Krishna Dasarathan Shanmugam Department of Surgical Gastroenterology Jawaharlal Institute of Postgraduate Medical Education and ResearchPuducherry 605006India

Applying indocyanine green(ICG)fluorescence in surgery has created a new dimension of navigation surgery to advance in various *** research in this field is nascent and fragmented,necessitating academic efforts to gain a comprehensive *** present review aims to integrate diverse perspectives and recent advances in its application in gastrointestinal *** relevant articles were selected by using the appropriate keyword search in *** angiography and cholangiography property of ICG fluorescence is helpful in various hepatobiliary *** gastroesophageal and colorectal surgery,the lymphangiography and angiography property of ICG is applied to evaluate bowel vascularity and guide *** lack of objective parameters to assess ICG fluorescence has been the primary limitation when ICG is used to evaluate bowel *** optimum dose and timing of ICG administration need to be standardized in some new application areas in gastrointestinal *** tumor-specific ligands with fluorophores can potentially widen the fluorescence application to detect primary and metastatic gastrointestinal *** narrative review outlines prior contributions,limitations,and research opportunities for future studies across gastrointestinal *** findings of the present review would be helpful for scholars and practitioners to explore and progress in this exciting domain of gastrointestinal surgery.

关键词： Indocyanine green Fluorescence Navigation surgery Angiography Cholangiography Lymphangiography

Calcium phosphate conversion technique:A versatile route to develop corrosion resistant hydroxyapatite coating over Mg/Mg alloys based implants

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2022年第7期10卷 1821-1845页

作者： G.S.Hikku C.Arthi R.B.Jeen Robert K.Jeyasubramanian R.murugesan Medical Bionanotechnology Faculty of Allied Health SciencesChettinad Hospital and Research InstituteChettinad Academy of Research and EducationKelambakkamTamilnadu 603103India Nanobiotechnology Amirta Centre for Nanoscience and Molecular MedicineAmirtha Vishwa VidhyapeethamErnakulamKerala 682041India Department of Mechanical Engineering AAA College of Engineering and TechnologySivakasiTamilnadu 626005India Department of Chemistry Mepco Schlenk Engineering CollegeSivakasiTamilnadu 626005India Karpaga Vinayaga Institute of Medical Sciences and Research Centre PalayanoorTamilnadu 603308India

Globally,vast research interest is emerging towards the development of biodegradable orthopedic implants as it overcomes the toxicity exerted by non-degradable implants when fixed in the human body for a longer *** this context,magnesium(Mg)plays a major role in the production of biodegradable implants owing to their characteristic degradation nature under the influence of body ***,Mg is one of the essential nutrients required to perform various metabolic activities by the human cells,and therefore,the degraded Mg products will be readily absorbed by the nearby ***,the higher corrosion rate in the biological environment is the primary downside of using Mg implants that liberate H2gas resulting in the formation of ***,in certain cases,Mg undergoes complete degradation before the healing of damaged bone tissue and cannot serve the purpose of providing mechanical ***,many studies have been focused on the development of different strategies to improve the corrosion-resistant behavior of Mg according to the *** this regard,the present review focused on the limitations of using pure Mg and Mg alloys for the fabrication of medical implants and how the calcium phosphate conversion coating alters the corrosive tendency through the formation of hydroxyapatite protective films for enhanced performance in medical implant applications.

关键词： Biodegradable implants Magnesium Controlled corrosion Alloying Hydroxyapatite Calcium phosphate conversion coating

An Intelligent Deep Neural Sentiment Classification Network

在线全文

学校读者我要写书评

暂无评论

Intelligent Automation & Soft Computing 2023年第5期36卷 1733-1744页

作者： Umamaheswari Ramalingam Senthil Kumar murugesan Karthikeyan Lakshmanan Chidhambararajan Balasubramaniyan Department of Electronics and Instrumentation Engineering SRM Valliammai Engineering CollegeKattankulathurTamilnaduIndia Department of Computer Science and Engineering SRM Valliammai Engineering CollegeKattankulathurTamilnaduIndia Department of Electronics and Communications Engineering SRM Valliammai Engineering CollegeKattankulathurTamilnaduIndia

A Deep Neural Sentiment Classiﬁcation Network(DNSCN)is devel-oped in this work to classify the Twitter data *** attempts to extract the negative and positive sentiments in the Twitter *** main goal of the system is toﬁnd the sentiment behavior of tweets with minimum ambiguity.A well-deﬁned neural network extracts deep features from the tweets *** extracting features deeper and deeper,the text in each tweet is represented by Bag-of-Words(BoW)and Word Embeddings(WE)*** effectiveness of DNSCN architecture is analyzed using Twitter-Sanders-Apple2(TSA2),Twit-ter-Sanders-Apple3(TSA3),and Twitter-DataSet(TDS).TSA2 and TDS consist of positive and negative tweets,whereas TSA3 has neutral tweets ***,the proposed DNSCN acts as a binary classiﬁer for TSA2 and TDS databases and a multiclass classiﬁer for *** performances of DNSCN architecture are evaluated by F1 score,precision,and recall rates using 5-fold and 10-fold *** show that the DNSCN-WE model provides more accuracy than the DNSCN-BoW model for representing the tweets in the feature *** F1 score of the DNSCN-BW based system on the TSA2 database is 0.98(binary classiﬁcation)and 0.97(three-class classiﬁcation)for the TSA3 *** system provides better a F1 score of 0.99 for the TDS database.

关键词： Deep neural network word embeddings bag-of-words sentiment analysis text classiﬁcation

Behaviour of micro-and nano-alumina-reinforced Mg-3Zn-0.7Zr-1Cu alloy composites processed at different sintering temperatures

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2021年第1期40卷 143-155页

作者： Eacherath Suneesh murugesan Sivapragash Department of Production Engineering Vidya Academy of Science and TechnologyThrissur 680501.India Department of Mechanical Engineering PSN College of Engineering and TechnologyTirunelveli 627152Ind

This study aims to develop a magnesium-based hybrid composite via a powder metallurgy(PM)technique by simultaneously reinforcing the matrix(Mg-3 Zn-0.7 Zr-1 Cu)alloy with micro-alumina(3.0 wt%)and nano-alumina(0.5 wt%and 1.0 wt%)*** extensive processing involved two different sintering temperatures(400 and 450℃)followed by hot extrusion and a heat treatment *** study aimed to add to our understanding of the effects of sintering temperature and alumina content on the physical characteristics of Mg-based *** was revealed that increasing sintering temperature improves the density of composites by increasing their diffusion *** addition,significant improvements in the hardness,tensile properties and compressive properties of the composites were observed at higher sintering *** was also discovered that composites with higher alumina concentrations experienced agglomeration and were more porous than other composites.A micro-structural examination showed that composites with higher concentrations of nano-alumina had a finer grain structure than other composites and underwent a marginal reduction in grain ***,the tensile and compressive properties of composites decreased when the nano-alumina content was increased to 1.0 wt%.The magnesium hybrid composite containing 3.0 wt%micro-alumina and 0.5 wt%nano-alumina sintered at 450℃displayed the greatest tensile strength properties in all composites studied.A transformation from brittle to mixed-mode failure,with sufficient evidence of increased plastic deformation,was also noted in the hybrid *** present study suggests that adding up to 0.5 wt%nano-alumina and employing a higher sintering temperature enhances the overall characteristics of magnesium/alumina microcomposites.

关键词： Hybrid composite Powder metallurgy Alumina particulates Sintering temperature Mechanical characteristics