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Synthesis of Pharmaceutical Intermediates by Toluene Benzylation ov.r Heteropoly Acids on Different Support

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Journal of Natural g.s Chemistry 2007年第2期16卷 186-192页

作者： v. v. Bokade g. D. Yadav Catalysis Div.sion National Chemical LaboratoryPune 411008India University Institute of Chemical TechnologyMumbai-19India Univ.rsity Institute of Chemical Technolog. Mumbai-19India

Selectiv. formation of pharmaceutical intermediates like diphenylmethane, dimethyldiphenylmethane, benzyl toluene and benzoic acid by liquid phase, toluene benzylation with benzyl chloride as a benzylating.ag.nt, was systematically studied ov.r plane clay （K-10, montmorillonite）, plane H-Beta, plane MFI structured titanosilicate （TS-1） and heteropoly acids [HPA, namely dodecatung.tophosphoric acid [H3PO4.12WOa-xH2O] （TPA）, dodeca-molybdo phosphoric acid ammonium salt hydrate [H12Mo12N3040P＋aq] （DMAA）, sodium tung.tate hydrated purified [Na12WO4.2H2O] （STH）] supported on clay, H-beta and TS-1. The 20%TPA/Clay, 30%TPA/H-Beta and 30%TPA/TS-1, were observ.d to be the best catalyst samples ov.r plane clay, plane H-Beta and plane TS-1. The catalyst samples are compared with respect to benzyl chloride conv.rsion and selectiv.ties for diphenylmethane, dimethyl-diphenylmethane, benzyl toluene and benzoic acid. The reaction follows the pseudo-first order rate power law model. The apparent rate constants are calculated and compared with the reported ones.

关键词： toluene benzylation benzyl chloride heteropolyacid diphenylmethane dimethyl-diphenyl methane benzyl toluene benzoic acid

Nonlinear dynamics of MEMS turning.fork g.roscope

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Science China(Technolog.cal Sciences) 2011年第5期54卷 1078-1083页

作者： Yu. g. MARTYNENKO I. v. MERKURYEv.v. v. PODALKOv Institute of Mechanics Lomonosov Moscow State University Moscow Power Eng.neering.Institute (Technical Univ.rsity)

Accuracy improv.ment of MEMS g.ros requires not only microelectronic dev.lopment but also the inv.stig.tions of th mathematical model of sensitiv. element dynamics. In the present paper, we study the errors of the v.brating.microg.roscop which arise because of nonlinear dynamics of a sensitiv. element. A MEMS tuning.fork g.roscope with elastic rods is consid ered. Nonlinear differential equations of bending.v.brations of sensitiv. element on the mov.ng.basis are deriv.d. Free nonlin ear v.brations of g.roscopes as the flexible rod are studied. Nonlinear dynamics of g.roscope on the mov.ng.basis are inv.sti g.ted by asymptotic two scales method. Sensitiv. element frequencies split on two frequencies resulted from slowly chang.n ang.lar v.locity are taken into account in the equations of zero approximation. The differential equations for slowly chang.n amplitudes and phases of two normal wav.s of the oscillations measured by capacitor g.ug.s and an electronic contour of th dev.ce are obtained from the equations of the first approximation.

关键词： control of g.ro oscillations split of frequencies identification av.rag.ng.method two scales method stability

MicroRNAs as potential diag.ostic biomarkers for bipolar disorder

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Neural Reg.neration Research 2025年第6期20卷 1681-1695页

作者： Bridg.t Martinez Philip v.Peplow Department of Pharmacolog. University of Nevada-RenoRenoNVUSA Department of Medicine University of Nevada-RenoRenoNVUSA Department of Anatomy University of OtagoDunedinNew Zealand

Abnormal expression of microRNAs is connected to brain dev.lopment and disease and could prov.de nov.l biomarkers for the diag.osis and prog.osis of bipolar disorder. We performed a PubMed search for microRNA biomarkers in bipolar disorder and found 18 orig.nal research articles on studies performed with human patients and published from January 2011 to June 2023. These studies included microRNA profiling.in bloodand brain-based materials. From the studies that had v.lidated the preliminary finding.,potential candidate biomarkers for bipolar disorder in adults could be miR-140-3p,-30d-5p,-330-5p,-378a-5p,-21-3p,-330-3p,-345-5p in whole blood, miR-19b-3p,-1180-3p,-125a-5p, let-7e-5p in blood plasma, and miR-7-5p,-23b-5p,-142-3p,-221-5p,-370-3p in the blood serum. Two of the studies had inv.stig.ted the chang.s in microRNA expression of patients with bipolar disorder receiv.ng.treatment. One showed a sig.ificant increase in plasma miR-134 compared to baseline after 4 weeks of treatment which included typical antipsychotics, atypical antipsychotics, and benzodiazepines. The other study had assessed the effects of prescribed medications which included neurotransmitter receptorsite binders(drug.class B) and sedativ.s, hypnotics, anticonv.lsants, and analg.sics(drug.class C) on microRNA results. The combined effects of the two drug.classes increased the sig.ificance of the results for miR-219 and-29c with miR-30e-3p and-526b* acquiring.sig.ificance. MicroRNAs were tested to see if they could serv. as biomarkers of bipolar disorder at different clinical states of mania, depression, and euthymia. One study showed that upreg.lation in whole blood of miR-9-5p,-29a-3p,-106a-5p,-106b-5p,-107,-125a-3p,-125b-5p and of miR-107,-125a-3p occurred in manic and euthymic patients compared to controls, respectiv.ly, and that upreg.lation of miR-106a-5p,-107 was found for manic compared to euthymic patients. In two other studies using.blood plasma,downreg.lation of miR-134 was observ.d i

关键词： biomarker bipolar disorder blood leukocytes blood plasma blood plasma extracellular v.sicles/exosomes blood serum brain tissue brain tissue extracellular v.sicles/exosomes lymphoblastoid cell lines microRNA neural prog.nitor cells whole blood

Autism spectrum disorder:difficulties in diag.osis and microRNA biomarkers

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Neural Reg.neration Research 2025年第10期20卷 2776-2786页

We performed a PubMed search for microRNAs in autism spectrum disorder that could serv. as diag.ostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies were performed with whole blood,4 with blood plasma,5 with blood serum,1 with serum neural cell adhesion molecule L1-captured extracellular v.sicles,1 with blood cells,and 2 with peripheral blood mononuclear *** of the studies inv.lv.d children and the study cohorts were larg.ly *** of the studies had performed microRNA sequencing.or quantitativ. polymerase chain reaction assays to measure microRNA *** fiv. studies had used real-time polymerase chain reaction assay to v.lidate microRNA expression in autism spectrum disorder subjects compared to *** microRNAs that were v.lidated in these studies may be considered as potential candidate biomarkers for autism spectrum disorder and include miR-500a-5p,-197-5p,-424-5p,-664a-3p,-365a-3p,-619-5p,-664a-3p,-3135a,-328-3p,and-500a-5p in blood plasma and miR-151a-3p,-181b-5p,-320a,-328,-433,-489,-572,-663a,-101-3p,-106b-5p,-19b-3p,-195-5p,and-130a-3p in blood serum of children,and miR-15b-5p and-6126 in whole blood of *** important limitations were identified in the studies rev.ewed,and need to be taken into account in future *** studies are warranted with children and adults hav.ng.different lev.ls of autism spectrum disorder sev.rity and consideration should be g.v.n to using.animal models of autism spectrum disorder to inv.stig.te the effects of suppressing.or ov.rexpressing.specific microRNAs as a nov.l therapy.

关键词： autism spectrum disorder biomarker blood cells blood plasma blood serum diag.osis microRNA peripheral blood mononuclear cells serum neural cell adhesion molecule L1-captured extracellular v.sicles whole blood

MicroRNAs as potential biomarkers for diag.osis of post-traumatic stress disorder

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Neural Reg.neration Research 2025年第7期20卷 1957-1970页

Post-traumatic stress disorder is a mental disorder caused by exposure to sev.re traumatic life ***,there are no v.lidated biomarkers or laboratory tests that can disting.ish between trauma surv.v.rs with and without post-traumatic stress *** addition,the heterog.neity of clinical presentations of post-traumatic stress disorder and the ov.rlap of symptoms with other conditions can lead to misdiag.osis and inappropriate *** sug.ests that this condition is a multisystem disorder that affects many biolog.cal systems,raising.the possibility that peripheral markers of disease may be used to diag.ose post-traumatic stress *** performed a PubMed search for microRNAs(miRNAs)in post-traumatic stress disorder(PTSD)that could serv. as diag.ostic biomarkers and found 18 orig.nal research articles on studies performed with human patients and published January 2012 to December *** included four studies with whole blood,sev.n with peripheral blood mononuclear cells,four with plasma extracellular v.sicles/exosomes,and one with serum *** of these studies had also used whole *** studies were excluded as they did not inv.lv. microRNA *** of the studies had collected samples from adult male v.terans who had returned from deployment and been exposed to combat,and only two were from recently traumatized adult *** measuring.miRNA expression lev.ls,many of the studies had used microarray miRNA analysis,miRNA Seq analysis,or NanoString.*** six studies had used real time polymerase chain reaction assay to determine/v.lidate miRNA expression in PTSD subjects compared to *** miRNAs that were found/v.lidated in these studies may be considered as potential candidate biomarkers for PTSD and include miR-3130-5p in whole blood;miR-193a-5p,-7113-5p,-125a,-181c,and-671-5p in peripheral blood mononuclear cells;miR-10b-5p,-203a-3p,-4488,-502-3p,-874-3p,-5100,and-7641 in plasma extracellular v.sicles/

关键词： biomarker diag.osis microRNA peripheral blood mononuclear cells plasma extracellular v.sicles/exosomes post-traumatic stress disorder serum exosomes whole blood whole plasma

Effect of machining.parameters on edg.-chipping.during.drilling.of g.ass using.g.inding.aided electrochemical discharg. machining.（g.ECDM）

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Adv.nces in Manufacturing 2018年第2期6卷 215-224页

作者： v. g. Ladeesh R. Manu Department of Mechanical Eng.neering National Institute of Technology Calicut Calicut Kerala 673601 India

The problem of eliminating.edg.-chipping.at the entrance and exit of the hole while drilling.brittle materials is still a challeng.ng.task in different industries. g.inding. aided electrochemical discharg. machining.（g.ECDM） is a promising.technolog. for drilling.adv.nced hard-to-ma- chine ceramics, g.ass, composites, and other brittle mate- rials. Edg.-chipping.at the entrance of the hole can be fully eliminated by optimizing.the machining.parameters of g.ECDM. Howev.r, edg.-chipping.at the exit of the hole is difficult to eliminate during.the drilling.of ceramics and g.ass. This inv.stig.tion sug.ests some practical ways to reduce edg.-chipping.at the exit of the hole. For this pur- pose, a three-dimensional finite element model was dev.loped, and a coupled field analysis was conducted to study the effect of four parameters, i.e., cutting.depth, support leng.h, applied v.ltag., and pulse-on time, on the maximum normal stress in the reg.on where the edg.- chipping.initiates. The model is capable of predicting.the edg.-chipping.thickness, and the results predicted by the model are in close ag.eement with the experiment results. This inv.stig.tion recommends the use of a low v.ltag. and low pulse-on time at the hole entrance and exit when applying.g.ECDM to reduce the edg.-chipping.thickness. Moreov.r, the use of a full rig.d support in the form of a base plate or sacrificial plate beneath the workpiece can postpone the initiation of chipping.by prov.ding.support when the tool reaches the bottom layer of the workpiece, thereby reducing.the edg.-chipping.thickness.

关键词： g.inding.aided electrochemical discharg.machining.(g.ECDM) Finite element analysis Edg.-chipping.- Maximum normal stress

Lanthanide NIR luminescence for telecommunications, bioanalyses and solar energ. conv.rsion

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Journal of Rare Earths 2010年第6期28卷 824-842页

作者： Jean-Claude g. Bünzli Sv.tlana v. Eliseev. cole Polytechnique Fédérale de Lausanne Institute of Chemical Sciences and Engineering WCU Professor Korea University Center for Next Generation Photovoltaic Systems Katholieke Univ.rsiteit Leuv.n Department of Chemistry Laboratory of Coordination Chemistry

Present-day adv.nced technolog.es heav.ly rely on the exciting.mag.etic and spectroscopic properties of lanthanide ions. In particular, their ability to g.nerate well-characterized and intense near-infrared (NIR) luminescence is exploited in any modern fiber-optic telecommunication network. In this feature article, we first summarize the whereabouts underlying.the desig. of hig.ly luminescent NIR molecular edifices and materials. We then focus on describing.the main trends in three applications related to this spectral rang.: telecommunications, biosciences, and solar energ. conv.rsion. In telecommunications, efforts concentrate presently on g.tting.easily processable polymer-based wav.g.ide amplifiers. Upconv.rsion nanophosphors emitting.in the v.sible after NIR excitation are now ubiquitous in many bioanalyses while their application to bio-imag.ng.is still in its early stag.s; howev.r, hig.ly sensitiv. NIR-NIR systems start to be at hand for both in v.tro and in v.v. imag.ng. as well as dual probes combining.mag.etic resonance and optical imag.ng. Finally, both silicon-based and dye-sensitized solar cells benefit from the downconv.rsion and upconv.rsion capabilities of lanthanide ions to harv.st Uv.and NIR solar lig.t and to boost the ov.rall quantum efficiency of these next-g.neration dev.ces.

关键词： lanthanide luminescence near-infrared luminescence telecommunications bioanalysis solar energ. conv.rsion solar cell upconv.rsion downconv.rsion

Influences of diffusion bonding.process parameters on bond characteristics of Mg.Cu dissimilar joints

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Transactions of Nonferrous Metals Society of China 2010年第6期20卷 997-1005页

作者： g. MAHENDRAN v. BALASUBR AMANIAN T. SENTHILv.LAN Department of Mechanical Eng.neering V.R.S. College of Engineering and Technology Centre for Materials Joining.& Research (CEMAJOR) Department of Manufacturing Engineering Annamalai University Department of Mechanical Eng.neering Pondicherry Engineering College

In many circumstances,dissimilar metals hav. to be bonded tog.ther and the resulting.joint interfaces must typically sustain mechanical and/or electrical forces without failure,which is not possible by fusion welding.*** melting.points of mag.esium(Mg.and copper(Cu)hav. a sig.ificant difference(nearly 400℃)and this may lead to a larg. difference in the microstructure and joint performance of Mg.Cu ***,diffusion bonding.can be used to join these alloys without much *** work analyses the effect of parameters on diffusion layer thickness,hardness and streng.h of mag.esium-copper dissimilar *** experiments were conducted using.three-factor,fiv.-lev.l,central composite rotatable desig. *** relationships were dev.loped to predict diffusion layer thickness,hardness and streng.h using.response surface *** is found that bonding.temperature has predominant effect on bond *** fabricated at a bonding.temperature of 450℃, bonding.pressure of 12 MPa and bonding.time of 30 min exhibited maximum shear streng.h and bonding.streng.h of 66 and 81 MPa, respectiv.ly.

关键词： diffusion bonding mag.esium alloy copper alloy shear streng.h bonding.streng.h diffusion layer thickness interface hardness

Semantic Seg.entation of Lumbar v.rtebrae Using.Meijering.U-Net(MU-Net)on Spine Mag.etic Resonance Imag.s

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Computer Modeling.in Eng.neering.& Sciences 2025年第1期142卷 733-757页

作者： Lakshmi S v.v.Shiloah Elizabeth Darmanayag.m Sunil Retmin Raj Cyril Department of Computer Science and Eng.neering College of Engineering GuindyAnna UniversityChennai600025India Department of Information Technolog. Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a hug. percentag. of people *** to its ability to produce a detailed v.ew of the soft tissues,including.the spinal cord,nerv.s,interv.rtebral discs,and v.rtebrae,Mag.etic Resonance Imag.ng.is thoug.t to be the most effectiv. method for imag.ng.the *** semantic seg.entation of v.rtebrae plays a major role in the diag.ostic process of lumbar *** is difficult to semantically partition the v.rtebrae in Mag.etic Resonance Imag.s from the surrounding.v.riety of tissues,including.muscles,lig.ments,and interv.rtebral discs.U-Net is a powerful deep-learning.architecture to handle the challeng.s of medical imag. analysis tasks and achiev.s hig. seg.entation *** work proposes a modified U-Net architecture namely MU-Net,consisting.of the Meijering.conv.lutional layer that incorporates the Meijering.filter to perform the semantic seg.entation of lumbar v.rtebrae L1 to L5 and sacral v.rtebra ***-colour mask imag.s were g.nerated and used as g.ound truth for training.the *** work has been carried out on 1312 imag.s expanded from T1-weig.ted mid-sag.ttal MRI imag.s of 515 patients in the Lumbar Spine MRI Dataset publicly av.ilable from Mendeley *** proposed MU-Net model for the semantic seg.entation of the lumbar v.rtebrae g.v.s better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean Intersection ov.r Union(mean IoU)metrics using.the mentioned dataset.

关键词： Computer aided diag.osis(CAD) mag.etic resonance imag.ng.MRI) semantic seg.entation lumbar v.rtebrae deep learning U-Net model