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heating and Cooling Performance of Earth-Tube heat Exchanger in a mechanical Ventilated farrowing house

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Journal of Agricultural Science and Technology(A) 2011年第2X期1卷 187-193页

作者： E. f. hessel C. Zurhake h. f. Van den Weghe Department Animal Sciences Georg-August-University Goettingen Division: Process Engineering Universitaetsstr. 7 Vechta D-49377 Germany

Earth tempering of stable air has attracted great attention as a sustainable air conditioning method in pig houses. At summer time air cooling of income air strongly reduces heat stress and required ventilation rate. At winter time heating costs can be reduced. The effect of air condition using geothermal energy was investigated in a farrowing house. Underneath the foundation of the farrowing house 88 non perforated ribbed tubes （diameter： 20 cm） were piped in a depth of 1.6-2.0 m. Over a period of 12 month following data were recorded at hourly intervals and analyzed： outside air temperature, as well as air temperature in the air supply duct and in the compartments. Incoming air （supply duct） was heated up to 20 ℃ during winter time and in summer time cooled by up to 15 ℃ compared to the outside air temperature. In contrast to the outside air diurnal variation, temperature fluctuations of the incoming air were reduced by 90%. Due to cooling of the incoming air at summer time the stable inside temperature could be limited to maximal 29 ℃（maximum outside temperature was 35℃）. Earth-tube heat exchangers with non perforated ribbed tubes were very efficient for air conditioning in farrowing houses. They were a cost effective supplement for sustainable cooling and heating of farrowing houses.

关键词： Earth heat exchanger heat stress reduction farrowing house air conditioning.

Effect of friction Stir Processing on Pitting Corrosion and Intergranular Attack of 7075 Aluminum Alloy

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Journal of materials Science & Technology 2017年第2期33卷 155-165页

作者： m. Navaser m. Atapour Department of materials Engineering Isfahan University of Technology Isfahan 84156-83111 Iran

The effect of friction stir processing （fSP） on the pitting corrosion and the intergranular attack of 7075 aluminum alloy was investigated. Three friction stir processed samples were produced by employing a constant tool travel speed of 100 mm/min at the rotating speeds of 630, 1000 and 1600 rpm. It was dem- onstrated that the processed samples suffered from both pitting and intergranular corrosion. Also, the sample processed at 1600 rpm exhibited the best pitting corrosion resistance. for all fS processed samples, the corrosion attack in the heat affected zone was pitting corrosion, whereas no intergranular corrosion was detected in this area.

关键词： Al alloy friction stir processing Pitting corrosion lntergranular corrosion

The Numerical Simulation of Storm-Surge and Coastal flooding in Western Taiwan： A Case Study of 2007 Typhoon SEPAT

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Journal of Shipping and Ocean Engineering 2011年第3期1卷 158-168页

作者： Y.h. Lin h.h. hwung m.C. fang faculty of hydraulic and Ocean Engineering National Cheng Kung University Tainan City 701 Taiwan China

A numerical model for simulating storm surge with nested grid system has been applied to hindcast the coastal flooding on both sides of Taiwan Strait. The simulation results can be used to understand the transport variation and the inundation distribution induced by the storm surge on the interested area during typhoon invades. The case in this study is Typhoon SEPAT, which passed through central Taiwan in 2007. The transport characteristics through Taiwan Strait under the influence of Typhoon SEPAT were discussed by comparing the field observations and numerical simulations during the typhoon period. The results indicate that the surge height of Typhoon SEPAT did not respond to the peak of wind waves accompanied with 15 hrs time lag. According to the influence of dynamical forces on the storm surge in Taiwan Strait, the onshore wind is the dominant role of coastal inundation during this typhoon event in Taiwan Strait. By observing the inundation map through the typhoon period, the coasts of Yulin County are verified to be the most serious affected area in the vicinity of Taiwan Strait.

关键词： flooding inundation storm surge typhoon SEPAT Taiwan Strait.

fatigue crack propagation in a helicopter component subjected to impact damage

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Defence Technology（防务技术） 2021年第2期17卷 416-428页

作者： m.fossati m.Pagani m.Giglio A.manes Politecnico di milano Dipartimento di Meccanicavia la Masa 1MilanoItaly

Damage tolerant methodology is increasingly used in aeronautical components,especially due the fact that the Aviation Regulation requires such an assessment in case an accidental damage *** present,there is a strong and actual interest in applying such procedures to helicopter components that are subjected to high frequency cyclic *** this paper,an investigation on a damaged transmission shaft for a tail rotor transmission of an actual helicopter has been carried out focusing on the fatigue crack propagation.A complete sequence of experimental tests was performed in order to create an actual ballistic damage and to subsequently check the damage tolerant *** shaft was damaged by oblique ballistic impact and was subsequently subjected to torsional fatigue *** the fatigue cycles several cracks propagated from the ballistic *** of these steps(impact and fatigue loading)were also simulated by a complex modelling approach based on finite Element models and fracture mechanics *** comparison between the experimental and numerical results shows a good agreement but it underlines the need for a very refined modelling technique capable to replicate all the features associated with the damage in order to reliably simulate the subsequent propagation phase.

关键词： Ballistic impact Damage fatigue Crack propagation

Carbonatites and Alkaline Igneous Rocks in Post-Collisional Settings:Storehouses of Rare Earth Elements

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Journal of Earth Science 2021年第6期32卷 1332-1358页

作者： Kathryn m.Goodenough Eimear A.Deady Charles D.Beard Sam Broom-fendley holly ALElliott frederick van den Berg hüseyinÖztürk British Geological Survey the Lyell CentreEdinburgh EH144APUK Institut des Sciences de la Terre UniversitéGrenoble Alpes38610 GièresFrance Camborne School of mines University of ExeterPenryn CampusPenryn TR109FEUK School of Environmental Sciences University of DerbyDerbyUK Department of Geological Engineering Istanbul University-CerrahpaşaAvcılar Campus34320 Avcılar IstanbulTurkey

The rare earth elements(REE)are critical raw materials for much of modern technology,particularly renewable energy infrastructure and electric vehicles that are vital for the energy *** of the world's largest REE deposits occur in alkaline rocks and carbonatites,which are found in intracontinental,rift-related settings,and also in syn-to post-collisional ***-collisional settings host significant REE deposits,such as those of the mianning-Dechang belt in *** paper reviews REE mineralization in syn-to post-collisional alkaline-carbonatite complexes worldwide,in order to demonstrate some of the key physical and chemical features of these *** use three examples,in Scotland,Namibia,and Turkey,to illustrate the structure of these *** review published geochemical data and use these to build up a broad model for the REE mineral system in post-collisional alkaline-carbonatite *** is evident that immiscibility of carbonate-rich magmas and fluids plays an important part in generating mineralization in these settings,with REE,Ba and f partitioning into the carbonate-rich *** most significant REE mineralization in post-collisional alkaline-carbonatite complexes occurs in shallow-level,carbothermal or carbonatite intrusions,but deeper carbonatite bodies and associated alteration zones may also have REE enrichment.

关键词： post-collisional alkaline carbonatite rare earth elements tectonics carbon cycle

Genetic Optimization of Artificial Neural Networks to forecast Virioplankton Abundance from Cytometric Data

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Journal of Intelligent Learning Systems and Applications 2013年第1期5卷 57-66页

作者： Gilberto C.Pereira marilia m.f.de Oliveira Nelson f.f.Ebecken Civil Engineering Program Federal University of Rio de JaneiroCenter of TechnologyFundao IslandRio de JaneiroBrasil

Since viruses are able to influence the trophic status and community structure they should be accessed and accounted in ecosystem functioning and management models. So, this work met a set of biological, chemical and physical time series in order to explore the correlations with marine virioplankton community across different trophic gradients. The case studied is the Arraial do Cabo upwelling system, northeast of Rio de Janeiro State in Southeast coast of Brazil. The main goal is to evolve three type of artificial neural network (ANN) by genetic algorithm (GA) optimization to predict virioplankton abundance and dynamic. The input variables range from the abundance of phytoplankton, bacterioplankton and its ratios acquired by one in situ and another ex situ flow cytometers. These data were collected with weekly frequency from August 2006 to June 2007. Our results show viruses being highly correlated to their host, and that GA provided an efficient method of optimizing ANN architectures to predict the virioplankton abundance. The RBf-NN model presented the best performance to an accuracy of 97% for any period in the year. A discussion and ecological interpretations about the system behavior is also provided.

关键词： Virioplankton Prediction flow Cytometry Neural Networks Genetic Algorithm Trophic Gradients

Global mapping of volumetric water retention at 100,330 and 15000 cm suction using the WoSIS database

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International Soil and Water Conservation Research 2023年第2期11卷 225-239页

作者： maria Eliza Turek Laura Poggio Niels h.Batjes Robson Andre Armindo Quirijn de Jong van Lier Luis de Sousa Gerard B.m.heuvelink ISRIC-World Soll Information Wageningemthe Netherlands Graduate Program in Environmental Engineering Federal University of ParunaCurtibaR Brazil Soll Geography and Landscope Group Wageningen University Wageningenthe Netherlands Department of Physics Federul University of LavrasMGBrarll CENA-Universiy of Sao Poulo PinacicabasaoBrazil

Present global maps of soil water retention(SWR)are mostly derived from pedotransfer functions(PTfs)applied to maps of other basic soil *** an alternative,'point-based'mapping of soil water content can improve global soil data availability and *** developed point-based global maps with estimated uncertainty of the volumetric SWR at 100,330 and 15000 cm suction using measured SWR data extracted from the WoSIS Soil Profile Database together with data estimated by a random forest PTf(PTf-Rf).The point data was combined with around 200 environmental covariates describing vegetation,terrain morphology,climate,geology,and hydrology using *** total,we used 7292,33192 and 42016 SWR point observations at 100,330 and 15000 cm,respectively,and complemented the dataset with 436108 estimated values at each *** cross-validation yielded a Root mean Square Error(RmSE)of6380,7.112 and 6.48510^(-2)cm^(3)cm^(-3),and a model Efficiency Coefficient(mEC)of0.430,0386,and 0.471,respectively,for 100,330 and 15000 *** results were also compared to three published global maps of SWR to evaluate differences between point-based and map-based mapping ***-based mapping performed better than the three map-based mapping approaches for 330 and 15000 cm,while for 100 cm results were similar,possibly due to the limited number of SWR observa-tions for 100 *** sources or uncertainty identified included the geographical clustering of the data and the limitation of the covariates to represent the naturally high variation of SWR.

关键词： Digital soil mapping Soil hydraulic properties Pedometrics SoilGrids

Picomolar antimalarial agent from a Chinese medicinal plant

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Science China Chemistry 2022年第1期65卷 82-86页

作者： Bin Zhou flavia m.Zimbres Joshua h.Butler Cheng-hui Xu Reagan S.haney Yan Wu maria B.Cassera Jian-min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Department of Biochemistry and molecular Biology Center for Tropical and Emerging Global Diseases(CTEGD)University of GeorgiaAthensGeorgia 30602United States

In our long-term efforts searching for antimalarial agents from Chinese medicinal plants,seven novel dimeric sesquiterpenoids(1–7)with significant antimalarial activity were isolated and characterized from the whole plants of Sarcandra glabra *** by solid data acquired by diverse *** them,compound 3 with an EC50 value of 4.3 pm against the chloroquine-resistant Plasmodium falciparum is the most potent antimalarial agent reported hitherto,about 1,000-fold stronger than *** article further consolidates and refines our previously delineated structure-activity relationship for this antimalarial compound class.

关键词： medicinal plants dimeric sesquiterpenoids antimalarial agent structure-activity relationship

Low serum levels of ghrelin are associated with gallstone disease

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World Journal of Gastroenterology 2006年第19期12卷 3096-3100页

作者： Nahum méndez-Sánchez Guadalupe Ponciano-Rodríguez Luisa Bermejo-martínez Antonio R Villa Norberto C Chávez-Tapia Daniel Zamora-Valdés Raúl Pichardo-Bahena Blanca Barredo-Prieto martha h Uribe-Ramos martha h Ramos héctor A Baptista-González misael Uribe Liver Unit Biomedical Research Department Medica Sur Clinic and FoundationMexico CityMexico faculty of medicine National Autonomous University of mexico (UNAm) Mexico CityMexico Clinical Research Department National Institute of Perinatology Mexico CityMexico Clinical Epidemiology Unit National Institute of medical Sciences and Nutrition Mexico CityMexico

AIm： To explore the role of ghrelin in gallstone disease. mEThODS： We carried out a cross-sectional study in 150 subjects, 38 with gallstones （cases） and 112 controls. We also did a real-time PCR-RT study in twenty gallbladder samples each. Body mass index （BNI）, serum insulin, ghrelin, and serum lipids were measured. Logistic regression analyses （univariate and multivariate） were conducted to estimate the probability of gallstone disease associated with serum ghrelin concentrations. RESULTS： Cases were statistically different from controls in gender distribution （P = 0.01）, age （53 vs 44 yr, P = 0.002）, BNI （28 vs 25; P = 0.004）, and glucose （5.26 vs 4.98 mmol/L; P = 0.05）. The prevalence of ghrelin serum levels above the third tercile was lower in subjects without metabolic syndrome （P 〈 0.05）. In a multivariate model, we found a protective effect, when ghrelin values were higher than the median value （OR = 0.27, 95%CI 0.09-0.82, P = 0.02）. Twenty （20%） gallbladder specimens expressed ghrelin mRNA. CONCLUSION： Serum ghrelin concentrations are associated with a protective effect of GD.

关键词： Gallstones Obesity Ghrelin Gallbladder Gastrointestinal hormones