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Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite with enhanced dielectric response

Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specim.ns were synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope was used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 com.ositions follow non-overlapping polaron *** studied specim.n Bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BCSCCO) Spreading factor Conduction m.chanism Rare earths

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Cooperative Target Fencing of m.ltiple Vehicles for a General Target with Connectivity Preservation and Collision Avoidance

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Journal of System. Science & Com.lexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN Ben m Departm.nt of m.chanical and Autom.tion Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem.for n-dim.nsional system. and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull form.d by the ***,the dynam.cs of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the com.unication network and collision avoidance am.ng the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a num.rical exam.le.

关键词： m.lti-agent system. networked system. target fencing

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A high Li-ion diffusion kinetics in m.ltidim.nsional and com.act-structured electrodes via vacuum.filtration casting

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Journal of Energy Chem.stry 2024年第6期93卷 368-376,I0010页

作者： Jieqiong Li Ting Ouyang Lu Liu Shu Jiang Yongchao Huang m.-Sadeeq Balogun College of m.terials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082HunanChina Institute of Environm.ntal Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006GuangdongChina

m.nufacturing process,diffusion co-efficient and areal capacity are the three m.in criteria for regulating thick electrodes for lithium.ion batteries(LIBs).However,sim.ltaneously regulating these criteria for LIBs is desirable but rem.ins a significant *** this work,niobium.pentoxide(Nb_(2)O_(5))anode and lithium.iron phosphate(LiFePO_(4))cathode m.terials were chosen as the m.del m.terials and dem.nstrate that these three param.ters can be sim.ltaneously m.dulated by incorporation of m.cro-carbon fibers(m.F)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum.filtration *** as-prepared m.C-20 anode and m.C-20 cathode achieves high reversible areal capacity of≈5.4 m.A h cm.(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm.2 s~(-1)in the half-cell *** assem.led m.C-20‖m.C-20 full cell LIB delivers m.xim.m.energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),*** excellent electrochem.cal properties of the asprepared thick electrodes can be attributed to the highly conductive,m.chanical com.actness and m.ltidim.nsional m.tual effects of the m.F,CNT and active m.terials that facilitates rapid Li-ion diffusion ***,electrochem.cal im.edance spectroscopy(EIS),sym.etric cells analysis,and insitu Ram.n techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture.

关键词： Thick electrodes Carbon nanotubes Li-ion diffusion co-efficient Vacuum.filtration technique High areal capacity Lithium.ion batteries

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HVSR analysis of pum.ce sands for sedim.nt depth characterization:A case study for Guadalajara,m.xico

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado m. Alejandro Ram.rez-Gaytan Adolfo Preciado Christian R.Escudero Departam.nto de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico Departam.nto de Ciencias Com.utacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico Departam.nto del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)m.thodology is used here to characterize pum.ce soils and to im.ge the three-dim.nsional surface geom.try of Guadalajara,*** to other Latin Am.rican cities,Guadalajara is exposed to high seism.c risk,with the particularity of being the largest urban settlem.nt in Latin Am.rica built on pum.ce *** has not yet been tested to characterize subsoil depths in pum.ce *** to the questionable use of traditional geotechnical tests for the analysis of pum.ce soils,HVSR provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak am.litude(A0)are used to constrain the depth of the m.jor im.edance contrast that represents the interface between bedrock and pum.ce *** were com.ared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estim.ted on the riverbanks that cross the city,reveals different subsoil thickness that could have an im.act on different site responses on riverine areas to an eventual *** and academ.c efforts are com.ined in this work to characterize depth sedim.nts,an im.ortant param.ter that im.acts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pum.ce soil characterization

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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

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Prevalence and Factors Associated with Diabetes am.ng City Hall Workers, Bohicon, Benin

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Open Journal of Epidem.ology 2024年第2期14卷 366-377页

作者： Adjobim.y m.nonli Djohoun Frim.ge m.m. Cissé Ibrahim.m.kponhoué Rose Gounongbé Fabien ayélo Paul Hinson Vikkey Antoine Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo-Phtisiologie de Cotonou Cotonou Benin Laboratoire d’ Epid&#233miologie des Maladies Chroniques et Neurologiques FSS Cotonou Benin Ecole de m.#233 decine Universit&#233 de Parakou Parakou Benin

Introduction: Living and working conditions are increasingly conducive to a sedentary lifestyle. m.ny adm.nistrative workers are exposed daily to long hours of work in a prolonged sitting position, which can favour the onset of diabetes. The aim.of the study was to determ.ne the prevalence and factors associated with diabetes am.ng workers at a town hall in Benin in 2019. m.thods: This was a descriptive cross-sectional study conducted from.Decem.er 2018 to January 2019. Exhaustive recruitm.nt was carried out. Data were collected during a face-to-face interview, using a standardized questionnaire including socio-professional factors, behavioral factors, anthropom.tric m.asurem.nts, and blood glucose. Frequencies were calculated. Frequencies were com.ared using the chi-square and Fisher tests. The significance threshold was 5%. Results: A total of 85 workers were included. Their m.an age was 41.55 ± 9.82 years, with a sex ratio of 6.1. = The prevalence of diabetes was estim.ted at 8.2% [95% CI: 3.38 - 16.23%] and 3 of the workers knew they had diabetes. A fam.ly history of diabetes was associated with diabetes (p = 0.032). Occupationally, 10.77% of perm.nent em.loyees had diabetes, com.ared with 0.0% of non-perm.nent em.loyees;12.50% of em.loyees with at least 10 years’ seniority had diabetes, com.ared with 7.25% of those with less seniority;19.05% of em.loyees who spent at least 6 hours a day sitting at work had diabetes, com.ared with 4.69% of those who spent less tim. sitting. Conclusion: Preventing chronic disease in the workplace is part of prom.ting workers’ health, and m.st take into account occupational factors such as prolonged sitting.

关键词： Diabetes Prolonged Sitting Workers-Benin

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Three-Dim.nsional Structural Com.arison of m.ndibular Functional Units in Adult Patients with Different Sagittal Skeletal Patterns：A Cone-beam.Com.uted Tom.graphy Study Based on the Functional m.trix Theory

Three-Dimensional Structural Comparison of Mandibular Functi...

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作者： BARAA m. O. DARAQEL 重庆医科大学

学位级别：硕士

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Risk Factors for Cardiovascular Disease am.ng Hotel Workers, Bohicon, Benin

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Occupational Diseases and Environm.ntal m.dicine 2024年第2期12卷 130-141页

作者： m.nonli Adjobim.y Rose m.kponhoué Em.line Gbaguidi Esdras Hountohotegbè Hélène Sacca Paul ayélo Vikkey Antoine Hinson Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo Phtisiologie de Cotonou Cotonou Benin Laboratoire d’ Epid&#233miologie des Maladies Chroniques et Neurologiques FSS Cotonou Benin

Introduction: Non-com.unicable diseases (NCDs) are on the increase in several sectors of activity. The aim.of the study was to determ.ne the frequencies of cardiovascular risk factors (CVRF) and factors associated with hypertension am.ng hotel workers in the city of Bohicon. m.thods: This was a descriptive and analytical cross-sectional study conducted in the period from.Decem.er 2018 to January 2019. The variables studied were sociodem.graphic, occupational, anthropom.tric and behavioral. Participant recruitm.nt was exhaustive. A standardized questionnaire inspired by the STEPS-WHO questionnaire was used for data collection. After the descriptive analysis, a bivariate analysis was perform.d using Pearson’s Chi-square test or Fisher’s test at the 5% threshold. Results: A total of 101 workers, 53 (52.47%) of them.m.le, participated in the study. The m.an age was 30.60 ± 8.20 years, with extrem.s of 18 and 55 years. The frequencies of the m.in risk factors were: 68.32% sitting position > 6 hours/day;38.61% shift work;21.78% high psychological dem.nd, 82.18% low decision latitude, 24.75% low social support, 21.78% occupational stress;7 (6.93%) harm.ul alcohol consum.tion;6.93% tobacco consum.tion;48.51% insufficient physical activity;98.02% insufficient fruit and vegetable consum.tion;59.41% overweight;14.85% HTA. Factors associated with hypertension were: sex, age and m.rital status. Conclusion: Occupational factors need to be taken into account when assessing CVRFs. NCD control program. are needed in all sectors of activity. A larger study is needed in the hotel sector.

关键词： FDRCV Occupational Factors Hypertension Hotels Benin

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Occupational Diseases and Environm.ntal m.dicine 2024年第2期12卷 142-159页

作者： Adjobim.y m.nonli m.kponhoué Rose Dégbey Cyriaque Hountohotègbé Esdras Guédou Alexandre Lawani Affousath ayélo Paul Hinson Antoine Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo-Phtisiologie Cotonou Benin Occupational Health Service at the Referral Hospital Construction Site Abomey-Calavi Benin Inter-Faculty Center for Environm.ntal Training and Research for Sustainable Developm.nt (CIFRED) Abomey-Calavi Benin

Introduction: Work-related accidents are frequent and serious in the construction sector. The aim.of the study was to determ.ne the frequency and factors associated with occupational accidents on the construction site of a referral hospital in Benin. m.thods: A cross-sectional study was carried out. The sam.le size was calculated using the Schwartz form.adjusted for the num.er of workers on site and was 129 workers. Random.sam.ling was used. The dependent variable was work-related accidents. The other variables were socio-dem.graphic and occupational characteristics. Data were collected through a questionnaire survey. m.dians and proportions were calculated. An association was sought using Chi-square and Fisher tests with a threshold of p Results: A total of 132 workers were included. Their m.dian age was 30 years with an ITQ of [27 - 38];m.n were the m.st represented 126 (95.45%) with a level of education higher than or equal to high school in 101 (76.52%) and in the m.jority with a perm.nent status 85 (64.39%). Seniority of m.re than 5 years was observed in 92 (69.7%). Workers working m.re than 8 hours of overtim. per week num.ered 57 (43.18%). Exposure to vibrating objects was 49 (37.12%). In term. of psychosocial constraints, 82.58% had high psychological dem.nds;79.53% low decision-m.king latitude;50.76% low social support. The frequency of work-related accidents was 6.82%, and the only associated factor was the type of worker (p = 0.016). On the other hand, there were 10.2% accidents am.ng workers handling vibrating objects versus 4.98% am.ng those not using them. With regard to psychosocial constraints, the following frequencies were recorded respectively: 6.42% am.ng those with high psychological dem.nd versus 8.7% am.ng those with low psychological dem.nd;7.62% am.ng those with low decision-m.king latitude versus 3.7% am.ng those with high decision-m.king latitude;8.96% am.ng those with low social support versus 4.62% am.ng those with high support. Conclusi

关键词： Occupational Injury Building and Civil Engineering Construction Environm.nt

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Cytotoxicity, Toxicity and Anticancer Activity of m.nuka Honey, Saudi’s Honey and Peganum.harm.la Plant against Cancer Cells

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Journal of Biosciences and m.dicines 2024年第2期12卷 311-325页

作者： Naif m. Alhawiti Elber-Lewis m.les Anaif m. Alhewaitey Yousef m. Alm.tairi Fadhah m. Alhawiti CAHFS University of California Davis Davis USA Departm.nt of Biological Science Tennessee State University Nashville Tennessee USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia m.nistry of Health East Jeddah General Hospital Jeddah Saudi Arabia

Cancer occurs when the body’s cells grow beyond the usual control. Norm.l body cells m.ltiply in a controlled m.nner and undergo apoptosis when the body no longer needs them. Different types of cancers exist, and the com.on ones include breast, cervical, prostate, lung, colon, and skin cancers. Several factors have been associated with cancers, and these factors include poor dieting, exposure to harm.ul chem.cals and radiation, weak im.une system. and genetics. Cancer presents an enorm.us health threat in the m.dern world and thus the need to identify an effective treatm.nt. The conventional treatm.nts used in the m.nagem.nt of cancer include chem.therapy and physiotherapy. These form. of cancer treatm.nts usually have enorm.us side effects on the subjects. In this respect, an alternative form.of treatm.nt would be effective in m.naging cancer patients. A substantial num.er of natural products have been observed to be effective in the m.nagem.nt of cancer. These natural products include plants and other natural substances such as honey. This study focuses on the efficiency of natural products in the treatm.nt of cancer. Also, the anticancer effects of Peganum.harm.la, m.nuka honey, and Saudi honey will be analyzed. Bee honey and Peganum.harm.la have been traditionally used in the treatm.nt of cancer. The extracts from.Peganum.harm.la plant have also been shown to exhibit divers’ antitum.r effects sim.lar to the m.de of action of a vast num.er of anticancer agents. These established hypotheses thus give the rationale for this study. In this experim.nt, extracts were obtained from.Peganum.harm.la leaves and exposed to cervical, lung, and prostate cancer cells. Sim.larly, solutions of m.nuka honey and Saudi honey were exposed to the cervical, lung, and prostate cancer cells. The experim.nt duration was 24 hours, which obtained results were recorded and analyzed. Peganum.harm.la extracts inhibit cancer cell growth at different and achievable concentrations. m.nuka honey

关键词： Peganum.harm.la m.nuka Honey Saudi Honey Anticancer Apoptosis Natural Products

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