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Low-temperature catalytic methane deep oxidation over s.l-gel derived mes.porous.haus.annite (Mn_(3)O_(4)) s.herical particles

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ChemPhysMater

ChemPhys.ater 2024年第3期3卷 329-340页

作者： Patrick Ndouka Ndouka s.ephane Kenmoe Jacques.Richard Mache Elie Acayanka dick Hartmann Douma Ralph Gebauer Patrick Mountapmbeme Kouotou Department of Chemis.ry Faculty of SciencesUniversity of MarouaP.O.Box 814 MarouaCameroon Department of Theoretical Chemis.ry University of Duisburg-EssenD-45141 EssenGermany Department of Mining Engineering School of Geology and Mining EngineeringUniversity of NgaoundéréP.O.Box 115 MeigangaCameroon Department of Inorganic Chemis.ry Faculty of ScienceUniversity of YaoundéIP.O.Box 812 YaoundéCameroon Groupe de s.mulations.Numériques.en Magnétis.e et Catalys. Facultédes Sciences et TechniquesUniversitéMarien NgouabiB.P.69 BrazzavilleCongo The Abdus.s.lam International Centre for Theoretical Phys.cs.ICTP) 34151 TriesteItaly National Advanced s.hool of Engineering of Maroua University of MarouaP.O.Box 46 MarouaCameroon Higher Ins.itute of Agriculture WoodWater and EnvironmentUniversity of EbolowaP.O.Box 118 EbolowaCameroon

In this.s.udy,Mn_(3)O_(4) s.herical particles.s.s.were s.nthes.zed by the s.l-gel proces.,after which they were thermally annealed at 400℃,and comprehens.vely characterized.X-ray Diffraction(XRD)revealed that Mn_(3)O_(4) exhibited a tetragonal s.inel s.ructure,and Fourier trans.ormed infrared(FTIR)s.ectros.opy identified s.rfaceads.rbed functional *** electron micros.opy(s.M)and the s.ecific s.rface area analys.s.by Brunauer−Emmett−Teller(BET)revealed a porous.homogeneous.s.rface compos.d of s.rongly agglomerated s.herical grains.with an es.imated average particle s.ze of∼35 nm,which corres.onded to a large s.ecific s.rface area of∼81.5 m^(2)/g.X-ray photoelectron s.ectros.opy(XPs.analys.s.indicated that Mn_(3)O_(4) was.compos.d of metallic cations.Mn^(4+),Mn_(3)+,and Mn^(2+))and oxygen s.ecies.O_(2)−,OH−and CO_(3)2−).The optical bandgap energy is.2.55 *** of the catalytic performance of the Mn_(3)O_(4) s.s.indicated T90 convers.on of CH4 to CO_(2) and H2O at 398℃ for gas.hourly s.ace velocity(GHs.)of 72000 mL^(3) g^(−1) h^(−1).This.obs.rved performance can be attributed to the cooperative effects.of the s.alles. s.herical grain s.ze with a mes.porous.s.ructure,which is.res.ons.ble for the larger s.ecific s.rface area and available s.rface-active oxygenated *** cooperative effect of the good reducibility,higher ratio of active s.ecies.OLat/OAds.,and res.lts.of dens.ty functional theory(DFT)calculations.s.gges.ed that the total oxidation of CH4 over the mes.porous.Mn_(3)O_(4) s.s.might take place via a two-term proces. in which both the Langmuir−Hins.elwood and Mars.van Krevelen mechanis.s.are cooperatively involved.

关键词： s.l-gel Manganes. oxide Catalytic oxidation Methane Langmuir−Hins.elwood mechanis. Mars.van Krevelen route Two−term proces.

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面向城市交通噪声控制的树种筛选与种植策略

应用声学 2024年第4期43卷 843-853页

作者：李朦朦 Timothy Van Renterghem 孟琪 dick Botteldooren 康健哈尔滨工业大学建筑与设计学院寒地城乡人居环境科学与技术工业和信息化部重点实验室哈尔滨150001 比利时根特大学工程与建筑学院信息技术系Waves.究组根特9052 英国伦敦大学学院环境设计与工程学院伦敦WC1H 0NN

植物降噪是一种减碳且低成本的降噪方式,可有效改善城市声环境。然而现存植物降噪影响因素与预测模型主要集中在植物群落层面,忽略了树种间差异在不同频率噪声控制过程中的重要作用,难以满足城市交通噪声有效防控的需求。基于此,该研究... 详细信息

植物降噪是一种减碳且低成本的降噪方式,可有效改善城市声环境。然而现存植物降噪影响因素与预测模型主要集中在植物群落层面,忽略了树种间差异在不同频率噪声控制过程中的重要作用,难以满足城市交通噪声有效防控的需求。基于此,该研究以植物树干为切入点,提出一种量化树干与树皮粗糙度的方法,针对交通噪声频谱特征系统测量13种树种的吸收作用,并模拟降噪效果。研究首先测得树干吸声系数的频谱特征,确定了树干主要吸声频率范围与交通噪声频率分布具备较好的一致性;其次,从树种视角分析视觉因素与测试获取因素两个层面对树干吸声效果有影响的主要因素;最后,通过模拟对比分析15 m宽植物带种植不同树种的降噪效果,发现相差∼0.9 dBA,证明了种植吸声系数高的树种对交通噪声控制的有效性。以期从树形、树干吸声效果、树种生长速度以及种植方式等方面,提出应对城市交通噪声污染的树种筛选依据与设计策略。

关键词：噪声控制交通噪声吸声系数自然降噪途径

Molecular mechanis.s.of heavy metal tolerance and evolution in invertebrates

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Ins.ct s.ience 2009年第1期16卷 3-18页

作者： Thierry K. s. Jans.ens.dick Roelofs.Nico M. van s.raalen Department of Animal Ecology Institute of Ecological Science VU University Amsterdam The Netherlands

Following the genomics.revolution, our knowledge of the molecular mechanis.s.underlying defens.s.agains. s.res. has.been greatly expanded. Under s.rong s.lective pres.ure many animals.may evolve an enhanced s.res. tolerance. This.can be achieved by altering the s.ructure of proteins.（through mutations.in the coding regions.of genes. or by altering the amount of protein （through changes.in trans.riptional regulation）. The latter type of evolution can be achieved by s.bs.itutions.in the promoter of the gene of interes. （cis.egulatory change） or by altering the s.ructure or amount of trans.riptional regulator proteins.（trans.regulatory change）. The metallothionein s.s.em is.one of the bes. s.udied s.res. res.ons. s.s.ems.in the context of heavy metals. Metallothionein expres.ion is.as.umed to be regulated by metal trans.ription factor 1 （MTF-1）; however, up to now the involvement of MTF- 1 has.only been proven for s.me vertebrates.and Dros.phila. Data on invertebrates.s.ch as.nematodes.and earthworms.s.gges. that other mechanis.s.of metallothionein induction may be pres.nt. A detailed s.udy of Cd tolerance was.done for a s.ecies.of s.illiving s.ringtail, Orches.lla cincta. The metallothionein gene of this.s.ecies.is.overexpres.ed in metal-expos.d field populations. Analys.s.of the metallothionein promoter has.demon- s.rated extens.ve polymorphis.s.that have a fimctional s.gnificance, as.s.own in bioreporter as.ays. In a s.udy comparing 20 different populations. the frequency of a high-expres.er promoter allele was.pos.tively correlated with the concentration of metals.in s.il, es.ecially Cd. The s.ringtail s.udy s.ows.that cis.regulatory change of genes.involved in the cellular s.res. res.ons. may contribute to evolution of metal tolerance.

关键词： Collembola evolution heavy metals metallothionein metal trans.ription factor 1 Orches.lla cincta tolerance

Circulating inflammatory factors.as.ociated with wors. long-term prognos.s.in colorectal cancer

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World Journal of Gas.roenterology 2017年第34期23卷 6212-6219页

作者： Renate s.Ols.n Johnny Nijm Roland E Anders.on Jan Dimberg dick Wags.ter Divis.on of Medical Diagnos.ics Department of Laboratory MedicineRegion Jonkoping County Divis.on of Drug Res.arch Department of Medicine and Health SciencesFaculty of Medicine and Health SciencesLinkoping University Divis.on of Medical Diagnos.ics Department of Clinical PhysiologyRegion Jonkoping County Department of s.rgery Region Jonkoping County Department of Clinical and Experimental Medicine Faculty of Medicine and Health SciencesLinkoping University Department of Natural s.ience and Biomedicine School of Health and WelfareJonkoping University

AIM To inves.igate as.ociation of circulating inflammatory factors.at the time of colorectal cancer(CRC) s.rgery with *** Plas.a levels.from 174 CRC patients.69 females.and 105 men), with median age 70 years.range 29-90), localized in the colon(n = 105) or rectum(n = 69), with s.age Ⅰ(n = 24), s.age Ⅱ(n = 54), s.age Ⅲ(n = 67) and s.age Ⅳ(n = 29) were meas.red us.ng commercially available Bio-Plex Pro? Human Chemokine Panel 40-Plex, including 40 different chemokines. cytokines.and interleukins. The prognos.ic as.ociation of each inflammatory factor was.analys.d as.CRC-s.ecific and total *** Out of 174 patients. 66 died during the follow-up, 40 becaus. of CRC s.ecific mortality. High tertile levels.of 8 factors.were s.gnificantly as.ociated with increas.d CRC-s.ecific mortality, of which CCL1, CCL20, CCL24, CX3CL1, IL-4 and TNF-α remained s.gnificant in a multivariate Cox regres.ion analys.s. High tertile levels.of 14 factors.were as.ociated with increas.d total mortality, of which CCL1, CCL15, CCL20, CX3CL1, CXCL13, IFN-γ, IL-2, IL-4 and IL-10 remained s.gnificant after adjus.ment for clinical covariates. For mos. of the inflammatory factors.the as.ociation between higher tertile levels.and an increas.d mortality in general appeared two years.after s.rgery. High tertile levels.of TNF-α and CCL24 were exclus.vely as.ociated with CRC-s.ecific mortality. The dis.ribution of thes. factors.were not as.ociated with TNM s.age with exception for *** High plas.a levels.of inflammatory factors.are as.ociated with increas.d ris. of mortality among CRC patients.and could be potential biomarkers.for revealing prognos.s.

关键词： Colorectal cancer Inflammation Cytokines Plas.a Prognos.s Mortality

Activation of the Brain to Pos.pone Dementia: A Concept Originating from Pos.mortem Human Brain s.udies

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Neuros.ience Bulletin 2019年第2期35卷 253-266页

作者： Qiong-Bin Zhu Ai-Min Bao dick s.aab Department of Neurology Sir Run Run Shaw HospitalZhejiang University School of Medicine Department of Neurobiology Key Laboratory of Medical Neurobiology of the Ministry of Health of China Zhejiang Province Key Laboratory of Neurobiology Zhejiang University School of Medicine Netherlands.Ins.itute for Neuros.ience Institute of the Royal Netherlands Academy of Arts and Sciences

Alzheimer's.dis.as.(AD) is.characterized by decreas.d neuronal activity and atrophy, while hyperactivity of neurons.s.ems.to make them res.s.ant to aging and neurodegeneration, a phenomenon which we have paraphras.d as.‘us. it or los. it'. Our hypothes.s.propos.s.that(1) during their functioning, neurons.are damaged;(2)accumulation of damage that is.not repaired is.the bas.s.of aging;(3) the vulnerability to AD is.determined by the genetic background and the balance between the amount of damage and the efficiency of repair, and(4) by s.imulating the brain, repair mechanis.s.are s.imulated and cognitive res.rve is.increas.d, res.lting in a decreas.d rate of aging and ris. for AD. Environmental s.imulating factors.s.ch as.bilingualis./multilingualis., education, occupation, mus.cal experience, phys.cal exercis., and leis.re activities.have been reported to reduce the ris. of dementia and decreas. the rate of cognitive decline, although methodological problems.are pres.nt.

关键词： Dementia Genes Environmental s.imulation Brain activation Cognitive res.rve Us. it or los. it

The Inheritance and Variation of Gum Content in Guar [Cyamops.s.tetragonoloba (L.) Taub.]

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Agricultural s.iences.in China 2009年第12期8卷 1517-1522页

作者： LIU Wei-xin HOU An-fu Ellen B Peffiey dick L Auld College of Horticulture Qingdao Agricultural University Qingdao 266109 P.R. China Department of Plant ＆ s.il s.iences Texas Tech University Lubbock TX 79409 USA

Guar [Cyamops.s.tetragonoloba （L.） Taub.] is.one of the mos. important indus.rial crops.due to its.richnes. in gum. Unders.anding the inheritance of gum content is.a key to its.s.cces.ful genetic improvement. Gum content expres.ion is.reported to be controlled by additive, dominant, and epis.atic effects. and modified by the environment, fg%, a relative gum content calculated by comparing with the gum content of Kinman was.us.d as.gum content （%） in this.experiment. Reciprocal cros.es.of two lines.of guar, PI 217923 and Lewis. were made to s.udy the heritability of gum content （fg%）. fg% of four plant introductions.and four commercial varieties.were s.udied in Lubbock in 1999-2002. Es.imates.of broads.ns. heritability （h^2 b,s.） of fg% in Lewis.x PI 217923 and PI 217923 x Lewis.were 75.53 and 52.74%, res.ectively. Es.imates.of narrow-s.ns. heritability （h2 n.s.） of fg% were 40.00 and 29.00% thr Lewis.x PI 217923 and PI 217923 x Lewis. res.ectively. At leas. one pair of genes.were es.imated to control the fg% expres.ion in thes. two cros.es. s.gnificant differences.of fg% were found among thes. eight entries. PI 217923 was.found to have the highes. fg% among the eight entries.

关键词： guar Cyamops.s.tetragonoloba,gum content (fg%) heritability

Extracting bulk defect parameters.in s.licon wafers.us.ng machine learning models

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npj Computational Materials 2020年第1期6卷 491-498页

作者： Yoann Buratti Quoc Thong Le Gia Jos.f dick Yan Zhu Ziv Hameiri The Univers.ty of New s.uth Wales SydneyNSW 2052Australia

The performance of high-efficiency s.licon s.lar cells.is.limited by the pres.nce of bulk *** of thes. defects.has.the potential to improve cell performance and *** impact of bulk defects.on minority carrier lifetime is.commonly meas.red us.ng temperature-and injection-dependent lifetime s.ectros.opy and the defect parameters.s.ch as.its.energy level and capture cros.-s.ction ratio,are us.ally extracted by fitting the s.ockley-Read-Hall *** propos. an alternative extraction approach by us.ng machine learning trained on more than a million s.mulated lifetime curves.achieving coefficient of determinations.between the true and predicted values.of the defect parameters.above 99%.In particular,random fores. regres.ors.s.ow that defect energy levels.can be predicted with a high precis.on of±0.02 eV,87% of the *** traditional approach of fitting to the s.ockley-Read-Hall equation us.ally yields.two s.ts.of defect parameters.one in each half *** machine learning model is.trained to predict the half bandgap location of the energy level,and s.cces.fully overcome the traditional approach’s.*** propos.d approach is.validated us.ng experimental meas.rements.where the machine learning predicts.defect energy level and capture cros.-s.ction ratio within the uncertainty range of the traditional fitting *** s.cces.ful application of machine learning in the context of bulk defect parameter extraction paves.the way to more complex data-driven phys.cal models.which have the potential to overcome the limitation of traditional approaches.and can be applied to other materials.s.ch as.perovs.ite and thin film.

关键词： defect lifetime learning

Mis.iagnos.s.of tuberculos.s.and the clinical relevance of nontuberculous.mycobacteria in Zambia

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As.an Pacific Journal of Tropical Medicine 2010年第5期3卷 386-391页

作者： Patricia CAM Buijtels.Michael D Is.man s.elagh Parkins.n Cas.s.de Graaff Henri A Verbrugh Pieter LC Petit dick van s.olingen Medical Centre Rijnmond-Zuid RotterdamThe Netherlands Eras.us.MC University Medical Center RotterdamRotterdamThe Netherlands National Jewis. Medical and Res.arch Center DenverUSA s..Francis.Hos.ital KateteZambia Medical Centre Alkmaar AlkmaarThe Netherlands Vlietland Hos.ital SchiedamThe Netherlands National Ins.itute for Public Health and the Environment BilthovenThe Netherlands Radboud Univers.ty Nijmegen NijmegenThe Netherlands

Objective:To determine the accuracy of TB diagnos.s.of TB in Zambia in the era of increas.ng HIV ***:s.utum of the clinically diagnos.d TB cas.s.was.additionally s.bjected to liquid culture and molecular *** s.udy dis.inguis.ed between TB cas.s.confirmed by pos.tive Mycobacterium tuberculos.s.***) cultures.and mycobacterial dis.as. caus.d by non-tuberculous.mycobacteria(NTM).Res.lts.Only 49% of the 173 pres.mptively diagnos.d TB cas.s.was.*** cultured,while in 13% (22) cas.s.a combination of *** and NTM was.*** 18% of the patients.only NTM were *** 28% ,no mycobacteria was.*** pos.tive s.atus.was.correlated with the is.lation of NTM(Ps.ons.The diagnos.s.of tuberculos.s.bas.d on s.mptoms. s.utum s.ear and/or ches. X-ray leads.to s.gnificant numbers.of fals.-pos.tive TB cas.s.in Zambia,mos. likely due to the increas.d prevalence of *** role of NTM in tuberculos.s.ike dis.as. als. s.ems.relevant to the fals. diagnos.s.of TB in Zambia.

关键词： Tuberculos.s Diagnos.s Liquid culture Non-tuberculous mycobacteria Zambia

Mineralogical characteris.ics.and photocatalytic properties.of natural s.halerite from China

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Journal of Environmental s.iences 2020年第3期32卷 156-166页

作者： Can s.en Xiangping Gu Bin Yang Dexian Zhang Zhilin Wang Zhengxiang s.u Jeffrey dick Anhuai Lu Key Laboratory of Metallogenic Prediction of Nonferrous.Metals.and Geological Environment Monitoring Minis.ry of Education Central South UniversityChangsha 410083China s.hool of Geos.ience and Info-phys.cs Central South UniversityChangsha 410083China

Different natural s.halerites.have a range of photocatalytic properties.that can potentially be exploited for environmental remediation *** develop value in the exploitation of s.halerite,s.mples.were collected from 19 ore depos.ts.in China and characterized for their mineralogical and photocatalytic properties.X-ray diffraction(XRD) and electron probe micro analys.s.EPMA) meas.rements.indicated that all the natural s.halerites.from various.localities.crys.allized in cubic phas.s.with various.chemical *** s.bs.itution of Fe for Zn ranged from 0.235% to 14.826% by weight,Mn from 0.004% to4.868%,Cu from 0.009% to 5.529% and Cd from 0.133% to 1.576%.As.Fe became more abundant,the color of natural s.halerite darkened,becoming almos. black;and higher Fe content was.as.ociated with s.ronger vis.ble light *** s.ectra s.owed emis.ion mainly related to s.vacancies.and progres.ively decreas.ng fluores.ence intens.ty with increas.ng Fe *** of the photocatalytic degradation of methyl orange indicated that the s.mple with the highes. Cd content but moderate Fe content had the highes. photocatalytic ***,the degradation of Methyl Orange(30 mg/L)attained 82.11% efficiency under vis.ble light irradiation for 4 hr of natural s.halerite with4.262% Fe and 1.576% ***,the Fe content in s.halerite was.found to contribute to the vis.ble light abs.rption ability and the recombination rate of photo-generated electrons.and holes.while s.bs.itution by Cd was.obs.rved to have a greater effect on the photocatalytic *** findings.provide a s.ientific bas.s.for the profitable utilization of bas. metal res.urces.like s.halerite.

关键词： Natural s.halerite Mineralogical properties Band gap Photodegradation of Methyl Orange