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Journal of Biomedical Research 2024年第3期38卷 278-286页

作者： Vishal p.dubey Varun p.Sureja dharmeshkumar B.Kheni department of Scientific and Medical Affairs Sundyota Numandis Probioceuticals Pvt.Ltd.AhmedabadGujarat 380015India

Menopause is characterized by various physical,mental and emotional *** 731®is a standardized extract from Rheum rhaponticum root and has been clinically studied for its role in reducing menopausal *** current systematic review and meta-analysis aimed to evaluate the efficacy of ERr 731®supplementation in alleviating the severity of menopausal *** this review,we searched across three online databases up to March 2023,evaluated the quality of the included studies by the physiotherapy Evidence database scale,and assessed the risk of bias by the Cochrane Risk of Bias *** then performed a metaanalysis using RevMan software to estimate the pooled mean difference(Md).The study protocol was registered in the prospective Register of Systematic Reviews(CRd42023416808).After screening and evaluation,we included four high-quality studies(a total of 390 participants;the ERr 731®group:193 participants;the control group:197 participants)in the *** results showed that ERr 731®supplementation significantly reduced the Menopause Rating Scale score(Md:–15.12;ppared with control *** analysis revealed no effect of individual studies on the overall pooled estimate or overall observed *** current review provides evidence that ERr 731®supplementation is effective in reducing menopause *** bias and high heterogeneity in the results warrant further clinical studies.

关键词： menopause Rheum rhaponticum hot flashes systematic review

On the analytical solution of transient friction in channel flows

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1447-1466页

作者： F.J.GARCíA-GARCíA p.FARINAS-ALVARINO department of Naval&Industrial Engineering Polytechnic School of EngineeringUniversity of A CorunaCampus Industrial de FerrolFerrol 15403A CorunaSpain Integraciones Técnicas de Seguridad S.A.Pol.Ind.Espiritu SantoC/Nobel15Cambre 15650A CorunaSpain

The transient friction in channel mean flows is the sum of two contributions,i.e.,the underlying laminar flow(ULF)and the purely turbulent component(pTC),and the contributions are analyzed separately by theoretical *** is found that,the transient friction may be higher or remarkably lower than that in equal-Reynolds number steady-state *** universal time constant for plane-parallel laminar flows is reported,and the role of the time constant in a turbulent mean flow is *** is shown that the time constant is related to the turbulence's frozen ***,a study of the logarithmic layer during the transient flow is accomplished,which shows that the logarithmic layer is destroyed.

关键词： transient friction transient flow unsteady channel flow

Removal of As(V)in the presence of Cr(VI)in contaminated water from the Bajio region of Mexico using ferrihydrite-functionalized graphene oxide(GOFH):A case study

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Emerging Contaminants 2024年第3期10卷 134-144页

作者： d.R.Joya-Cardenas J.p.Rodríguez-Caicedo M.A.Corona-Rivera N.Saldana-Robles C.E.damian-Ascencio A.Saldana-Robles Graduate program in Biosciences University of GuanajuatoIrapuato36500Mexico Facultad de Ingenierías y Tecnologías Instituto XeriraUniversidad de SantanderBucaramanga680003Colombia Chemical Engineering Unit Academic Multidisciplinary Region Altiplano UAMRA.Autonomous University of San Luis PotosíMatehualaSan Luis Potosí78000Mexico department of Agricultural Engineering University of GuanajuatoIrapuato36500Mexico department of Mechanical Engineering University of GuanajuatoSalamanca36800Mexico Mechanical Engineering department Virginia TechBlacksburgVA24061USA

The presence of heavy metals such as arsenic(As)and chromium(Cr)can be considered one of the most toxic heavy *** study aims to develop and evaluate a graphene oxide(GO)based material functionalized with ferrihydrite for the removal of As(V)in the presence of Cr(VI).The adsorbent ferrihydrite-functionalized graphene oxide(GOFH)was characterized by SEM,FTIR,XRd,XpS,surface charge,BET and *** adsorption capacities for As(V)and Cr(VI)were 160 and 66 mg g^(-1)respectively at pH 4 and 298 K,fitting the Langmuir *** binary systems,GOFH adsorbed As(V)with an adsorption capacity of 137 mg g^(-1)in the presence of 20 mg L^(-1)Cr(VI)at room *** analysis revealed an exothermic and spontaneous ***,GOFH effectively removed several coexisting anions from groundwater,including SO_(4)^(2-),CO_(3)^(2-)and Cl^(-).This work evidences the potential of GOFH for competitive adsorption of priority pollutants from complex *** GOFH material represents a technically and economically viable technology for application in groundwater decontamination,as it requires inexpensive precursors and ambient conditions during synthesis and operation.

关键词： Competition Ions Contamination Groundwater Adsorption capacity

Mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(pTFE)

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Friction 2024年第5期12卷 997-1015页

作者： pontus JOHANSSON p.MARKLUNd M.BJORLING Y.SHI division of Machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced polytetrafluoroethylene (CF/pTFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. Compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. Moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of CF/pTFE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/pTFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the CF/pTFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. Moreover, a loosely adhered tribofilm was observed on top of the CF/pTFE surface in presence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. The adsorbed water in the loosely adhered tribofilm coul

关键词： polymer composite tribofilm tribochemistry atmosphere

Assessment of Intangible Losses in Earthquake Engineering

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Open Journal of Civil Engineering 2024年第3期14卷 469-485页

作者： Jaime García-pérez Orlando díaz-López Eric García-López Instituto de Ingeniera Ingeniera Estructural Edif 2 Universidad Nacional Autnoma de Mxico Ciudad Universitaria Mexico City Mxico Cobertizo San pedro Mrtir s/n Facultad de Ciencias Jurdicas y Sociales Universidad de Castilla-La Mancha Toledo Espaa

In order to find optimum design parameters in earthquake engineering, an objective function is optimized. This function comprises the initial cost of a structure and the cost due to the damage of earthquakes. Intangible losses may be included in the latter, such as how much society is willing to invest to preserve a human life. In this paper, the expression of the objective function is developed in terms of the seismic design coefficient, and the aforementioned intangible loss is calculated from both the individual point of view and that of society. The calculation of the intangible is based on utility curves. Finally, optimum seismic design coefficients are calculated for a firm ground site.

关键词： Seismic Risk Optimum Coefficients Structural Reliability Intangible Losses Utility

Biocompatible Biphasic Iontronics Enable Neuron-Like Ionic Signal Transmission

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Research 2024年第3期2024卷 795-796页

作者： Xiaoyi Wang Aleksandar p.Ivanov Joshua B.Edel department of Chemistry Imperial College LondonMolecular Sciences Research HubLondon W12 OBZUK

Biocompatible connections between external artificial devices and living organisms show promise for future neuroprosthetics and *** study in Science by Zhao and colleagues introduces a cascade-heterogated biphasic gel(HBG)iontronic device,which facilitates electronic-to-multi-ionic signal transduction for abiotic–biotic *** by neuron signaling,the HBG device demonstrated its biocompatibility by regulating neural activity in biological tissue,paving the way for wearable and implantable devices,including brain–computer interfaces.

关键词： asi Signal Neuron

System integration analysis of a zeolite 13x thermal energy storage

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Energy and Built Environment 2024年第4期5卷 568-579页

作者： S.de Antonellis L.p.M.Colombo p.Castellazzi A.Rossetti L.Marocco politecnico di Milano Department of Energyvia Lambruschini 4Milan 20156Italy Ricerca sul Sistema Energetico-RSE S.p.A. Tecnologie di Generazione e Materialivia R.Rubattino 54Milan 20134Italy

Nowadays a major energy transition aimed at cutting CO 2 emissions has begun,with the ambitious goal of drasti-cally reducing the dependence on fossil fuels and promoting the use of renewable energy *** this context,energy storage systems play a key role in ensuring a stable,secure and time-aligned energy *** sorption thermal energy storages(TESs)can contribute to such transition,since they are simple and cheap devices able to provide a hot airflow with a high energy density and to store energy for long *** this work,open sorption TES systems operated with Zeolite13X are investigated with a focus on the integration in practical ***,the experimental analysis and modelling of the sole TES system is ***,the integration of the TES at system level is carried *** analysis evidences that a significant reduction of storage capac-ity occurs if air humidification is necessary before the adsorption process or afterwards to keep adequate indoor comfort conditions for the *** the exemplary case study considered,an energy density of 150 kWhm^(−3) can drop to 40 kWhm−3 in case of complete compensation of the adsorbed water through a *** paper provides useful guidelines for evaluating the performance of a TES integrated system in terms of specific energy and *** also identifies applications involving high latent loads(e.g.,swimming pools,locker rooms)or for which low relative air humidity is required(*** of vehicles to prevent condensation on windows)as particularly beneficial for using a TES system.

关键词： Energy storage Adsorption Zeolite System integration Numerical model

Application of flame-formed carbon nanoparticle films for ethanol sensing Author links open overlay panel

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particuology 2024年第8期91卷 202-210页

作者： pegah darvehi Luca Basta Mario Commodo patrizia Minutolo Andrea d'Anna Istituto di Scienze e Tecnologie per l’Energia e la MobilitàSostenibili Consiglio Nazionale delle RicercheP.le Tecchio 8080125NapoliItaly dipartimento di Ingegneria Chimica dei Materiali e della Produzione IndustrialeUniversitàdegli Studi di Napoli Federico IIP.le Tecchio 8080125NapoliItaly

Carbon nanoparticles(CNps)have received considerable attention due to their exceptional qualities and *** unique physical and chemical characteristics make them extremely intriguing as materials for numerous high-potential applications,such as electronics and gas *** study focused on producing carbon-based nanomaterial devices by deposition of flame-formed carbon nanoparticles on a suitable substrate and investigating their gas-sensing *** were produced in a fuel-rich laminar premixed ethylene/air flame and the collected CNp film was morphologically and electrically *** electrical conductivity of the film was investigated as a function of ethanol concentration and amount of deposited ***,CNp films exhibited high sensitivity to ambient ethanol gas concentrations,and rapid recovery times at room temperature,and showed a sensitivity increasing with the amount of deposited material and the surface *** findings demonstrate the high potential of combustion-generated CNps as building materials for low-cost and portable ethanol sensors.

关键词： Flame synthesis Carbon nanoparticles Soot Nanostructured thin film Optical and electrical characterization Atomic force microscopy Sensors

Anthropogenic Influence on decadal Changes in Concurrent Hot and dry Events over China around the Mid-1990s

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Advances in Atmospheric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buwen dONG Fangxing TIAN Nicholas p.KLINGAMAN Yunnan Key Laboratory of Meteorological disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China department of Atmospheric Sciences Yunnan UniversityKunming 650500China National Centre for Atmospheric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(HdEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HdE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HdEs averaged over China in the present day(pd,1994–2011) is double that in the early period(Ep, 1964–81);the duration of HdEs increases by 60%. Climate experiments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthropogenic forcing to HdE decadal changes over China. Anthropogenic forcing changes can explain 60%–70% of the observed decadal changes,suggesting an important anthropogenic influence on HdE changes over China across the mid-1990s. Single-forcing experiments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HdEs throughout China. The change in anthropogenic aerosol(AA) emissions significantly decreases the frequency and duration of HdEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HdEs in response to anthropogenic forcing are mainly due to the response of climatological mean surface air temperatures. The contributions from changes in variability and changes in climatological mean soil moisture and evapotranspiration are relatively small. The physical processes associated with the response of HdEs to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

Artificial ground freezing of underground mines in cold regions using thermosyphons with air insulation

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International Journal of Mining Science and Technology 2024年第5期34卷 643-654页

作者： Ahmad F.Zueter Mohammad Zolfagharroshan Navid Bahrani Agus p.Sasmito department of Civil and Resource Engineering Dalhousie UniversityHalifax B3H4R2Canada department of Mining Engineering McGill UniversityMontreal H3A0E8Canada

Current practice of underground artificial ground freezing(AGF)typically involves huge refrigeration systems of large economic and environmental *** this study,a novel AGF technique is proposed deploying available cold wind in cold *** is achieved by a static heat transfer device called thermosyphon equipped with an air insulation layer.A refrigeration unit can be optionally integrated to meet additional cooling *** introduction of air insulation isolates the thermosyphon from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration *** design is demonstrated using well-validated mathematical models from our previous work based on two-phase enthalpy method of the ground coupled with a thermal resistance network for the *** Canadian mines are considered:the Cigar Lake Mine and the Giant *** results show that our proposed design can speed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake ***,a cooling load of 2.4 GWh can be saved at the Cigar Lake ***,this study provides mining practitioners with sustainable solutions of underground AGF.

关键词： Artificial ground freezing Underground mining Sustainable mining Thermosyphon Air insulation Cold regions