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Effects of fibers on expansive shotcrete mixtures consisting of calcium sulfoaluminate cement,ordinary Portland cement,and calcium sulfate

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 212-221页

作者： h.yu L.Wu W.V.Liu Y.Pourrahimian School of Mining and Petroleum Engineering Department of Civil and Environmental Engineering University of Alberta

The mining industry often uses shotcrete for ground stabilization. however, cracking within shotcrete is commonly observed, which delays production schedules and increases maintenance costs. A possible crack reduction method is using expansive shotcrete mixture consisting of calcium sulfoaluminate cement(CSA), ordinary Portland cement(OPC), and calcium sulfate(CS) to reduce shrinkage. Furthermore, fibers can be added to the mixture to restrain expansion and impede cracking. The objective of this paper is to study the effects of nylon fiber, glass fiber, and steel fiber on an expansive shotcrete mixture that can better resist cracking. in this study, parameters such as density, water absorption, volume of permeable voids, unconfined compressive strength(UCS), splitting tensile strength(STS), and volume change of fiber-added expansive mixtures were determined at different time periods(i.e. the strengths on the 28 th day, and the volume changes on the 1 st, 7 th, 14 th, 21 st, and 28 th days). The results show that addition of fibers can improve mixture durability, in the form of decreased water absorption and reduced permeable pore space content. Moreover, the expansion of the CSA-OPC-CS mixture was restrained up to50% by glass fiber, up to 43% by nylon fiber, and up to 28% by steel fiber. The results show that the STS was improved by 57% with glass fiber addition, 43% with steel fiber addition, and 38% with nylon fiber addition. The UCS was also increased by 31% after steel fiber addition, 26% after nylon fiber addition, and16% after glass fiber addition. These results suggest that fiber additions to the expansive shotcrete mixtures can improve durability and strengths while controlling expansion.

关键词： Shotcrete Restrained expansion Fibers Calcium sulfoaluminate cement(CSA) Ordinary Portland cement(OPC) Calcium sulfate(CS)

Advances in Effects of Sound Waves on Plants

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Journal of integrative Agriculture 2014年第2期13卷 335-348页

作者： Reda h E hassanien hOU Tian-zhen Li yu-feng Li Bao-ming College of Water Resources and Civil Engineering China Agricultural University Agricultural Engineering Department Faculty of AgricultureCairo University Key Laboratory of Agricultural Engineering in Structure and Environment Ministry of Agriculture

Sound waves technology has been applied to different plants. it has been found that sound waves were at different frequencies, sound pressure levels （SPLs）, exposure periods, and distances from the source of sound influence plant growth. Experiments have been conducted in the open field and under greenhouse growing conditions with different levels of audible sound frequencies and sound pressure levels. Sound waves at 1 khz and 100 dB for 1 h within a distance of 0.20 m could significantly promote the division and cell wall fluidity of callus cells and also significantly enhance the activity of protective enzymes and endogenous hormones. Sound waves stimulation could increase the plant plasma-membrane iT-ATPase activity, the contents of soluble sugar, soluble protein, and amylase activity of callus. Moreover, sound waves could increase the content of RNA and the level of transcription. Stress-induced genes could switch on under sound stimulation. Sound waves at 0.1-1 khz and SPL of （70＋5） dB for 3 h from plant acoustic frequency technology （PAFT） generator within a distance ranged from 30 to 60 m every other day significantly increased the yield of sweet pepper, cucumber and tomato by 30.05, 37.1 and 13.2%, respectively. Furthermore, the yield of lettuce, spinach, cotton, rice, and wheat were increased by 19.6, 22.7, 11.4, 5.7, and 17.0%, respectively. Sound waves may also strengthen plant immune systems. it has been proved that spider mite, aphids, gray mold, late blight and virus disease of tomatoes in the greenhouses decreased by 6.0, 8.0, 9.0, 11.0, and 8.0%, respectively, and the sheath blight office was reduced by 50%. This paper provides an overview of literature for the effects of sound waves on various growth parameters of plant at different growth stages.

关键词： acoustic technology sound waves plants growth

Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 MeV

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Chinese Physics C 2024年第2期48卷 91-103页

作者： F.A.Rasulova N.V.Aksenov S.i.Alekseev R.A.Aliev S.S.Belyshev i.Chuprakov N.yu.Fursova A.S.Madumarov J.h.Khushvaktov A.A.Kuznetsov B.S.yuldashev Joint institute for Nuclear Research DubnaRussia institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan TashkentUzbekistan Faculty of Chemistry of Lomonosov Moscow State University MoscowRussia National Research Center"Kurchatov institute" MoscowRussia Skobeltsyn institute of Nuclear Physics of Lomonosov Moscow State University MoscowRussia Faculty of Physics of Lomonosov Moscow State University MoscowRussia institute of Nuclear Physics AlmatyRepublic of Kazakhstan

in this study,experiments were performed at bremsstrahlung end-point energies of 10-23 MeV with the beam from the MT-25 microtron using theγ-activation *** experimental values of relative yields were compared with theoretical results obtained on the basis of TALYS with the standard parameters and the combined model of photonucleon *** isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 ***,taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

关键词： bremsstrahlung photon cross section isospin splitting giant dipole resonance

Phylogenetic diversity of planktonic bacteria in the Chukchi Borderland region in summer

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Acta Oceanologica Sinica 2013年第6期32卷 66-74页

作者： ZENG Yinxin yu Yong Li huirong hE Jianfeng LEE Sang h SUN Kun Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of China College of Biological Engineering Jimei University Department of Oceanography Pusan National University

Planktonic bacteria are abundant in the Chukchi Borderland region. however, little is known about their di- versity and the roles of various bacteria in the ocean. Seawater samples were collected from two stations K2S and K4S where sea ice was melting obviously. The analysis of water samples with fluorescence in situ hybridization （FiSh） showed that DMSP-degrading bacteria accounted for 13% of the total bacteria at the station K2S. No aerobic anoxygenic phototrophic （AAP） bacteria were detected in both samples. The bacterial communities were characterized by two 16S rRNA gene clone libraries. Sequences fell into four major lineages of the domain Bacteria, including Proteobacteria （Alpha, Beta and Gamma subclasses）, Bac- teroidetes, Actinobacteria and Firmicutes. No significant difference was found between the two clone li- braries. SAR11 and Rhodobacteraceae clades of Alphaproteobacteria and Pseudoalteromonas of Gammapro- teobacteria constituted three dominant fractions in the clone libraries. A total of 191 heterotrophic bacterial strains were isolated and 76% showed extracellular proteolytic activity. Phylogenetic analysis reveals that the isolates fell into Gammaproteobacteria, Bacteroidetes, Actinobacteria and Firmicutes. The most common genus in both the bacterial isolates and protease-producing bacteria was Pseudoalteromonas. UniFrac data showed suggestive differences in bacterial communities between the Chukchi Borderland and the northern Bering Sea.

关键词： diversity planktonic bacteria 16S rRNA gene clone library Chukchi Borderland

Plant population and genotype effects override the effects of Epichloë endophyte species on growth and drought stress response of Achnatherum robustum plants in two natural grass populations

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Journal of Plant Ecology 2015年第6期8卷 633-641页

作者： Tong Jia Tatsiana Shymanovi.h.yu-Bao Gao Stanley h.Faeth Department of Plant Biology and Ecology College of Life SciencesNankai University94 Weijin RoadTianjin 300071China Department of Biology University of North Carolina Greensboro312 Eberhart Bldg.GreensboroNC 27412USA

Aims in cool-season grasses,systemic and vertically transmitted Epichloëinfections often provide a suite of benefits including increased growth,reproduction and competitive ***,these effects of Epichloëendophytes on their hosts often depend upon host and endophyte genotype and environmental *** Achnatherum robustum(sleepygrass)harbors at least two Epichloëspecies within natural populations in the southwest *** tested the effects of endophyte infection and species,host population and plant genotype(by experimentally removing the endophyte),and soil moisture(a key limiting factor)on growth and drought stress response of infected *** plants from two populations(Weed and Cloudcroft)in the sacremento mountains of New mexico,USA).important Findingsalthough the two populations harbor distinct Epichloëspecies each with very different chemoprofiles,neither endophyte status(infected ***)nor endophyte species affected most growth param-eters at 8 or 25 weeks of the experiment,except for leaf *** high water treatment,infected plants from the Weed population had longer leaf length compared with uninfected *** contrast,the population of origin affected all growth parameters,including plant height,leaf number,length and width,tiller number and shoot and root biomass,as well as wilting *** from the Cloudcroft population generally showed greater growth than grasses from the Weed *** infection did affect wilting time,with infection in the Weed population generally reducing time to wilting under low and high water,whereas infection in the Cloudcroft population reduced time to wilting only under high water *** results suggest that plant population and their associated plant genotypes may play a much larger role in endophyte-host grass interactions in varying environments than previously *** Epichloëspecies may be compatible with only specific host genotypes within populations such

关键词： endophyte genotype Epichloe infection growth parameters sleepygrass wilting time

Efficient photocatalytic reduction of chromium(Ⅵ) using photoreduced graphene oxide as photocatalyst under visible light irradiation

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Journal of Materials Science & Technology 2021年第32期91卷 17-27页

作者： Mei yu Jing Shang yu Kuang Department of Environment and health State Key Joint Laboratory of Environmental Simulation and Pollution ControlCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Graphene oxide(GO),a new and promising material,has been widely used as a co-catalyst in photocatalytic reactions;however,its capacity as a sole photocatalyst has rarely been *** this study,ultraviolet(UV) light irradiation was used as a modification method to obtain reduced GO(rGO) *** samples were used as photocatalysts to examine their visible light photocatalytic activity toward hexavalent chromium(Cr(Ⅵ)) *** force microscopy(AFM),X-ray diffraction(XRD),UV-vis spectrophotometry,Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and electron spin resonance(ESR) spectroscopy were applied to interpret the surface and structure changes with UV *** oxygen-containing functional groups(OFGs) on the GO surface were reduced to defective carbons andπ-conjugated C=C(sp^(2) domains) under UV light;this led to a decrease in the interlayer distance between GO sheets,GO fragmentation,and increased disorder on the GO *** restoration of sp^(2) domains led to a narrower band gap of GO,which favored the rGO excitation by visible light to generate electron-hole *** rGO pre-irradiated with UV for 1 h(rGO-1),possessing the highest defect density and electron generation efficiency,exhibited the best Cr(Ⅵ) reduction efficiency,which was about three times that of the GO sample;moreover,it outperformed most of the reported GO-based *** addition,low ph and the addition of citric acid as a hole scavenger could further improve the photocatalytic *** study proves that GO or rGO can be used as a sole photocatalyst under visible light to remove environmental pollutants such as heavy-metal ions,and it paves the way for the development of this kind of material and its UV-irradiation modification for further applications.

关键词： Graphene oxide Chromium(Ⅵ) Defect density UV-irradiation modification Photocatalytic reduction

Glaucoma surgery and induced astigmatism:a systematic review

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Eye and Vision 2017年第1期4卷 159-163页

作者： helen h.L.Chan yu Xiang G.Kong Royal Victorian Eye and Ear hospital 32 Gisborne StEast MelbourneVIC 3002Australia

Background:The refractive outcomes of glaucoma surgeries,particularly their effect on astigmatism,are incompletely *** body:Trabeculectomy is associated with a considerable amount of with-the-rule astigmatic change in the immediate postoperative *** is followed by a gradual against-the-rule *** changes are altered with the use of mitomycin C(MMC).Non-penetrating surgery such as deep sclerectomy is also associated with a similar or smaller degree of induced *** invasive glaucoma surgery appears to be astigmatically *** is no clear evidence regarding refractive outcomes of glaucoma drainage device ***:induced astigmatism may account for a reduction in unaided visual acuity in the early postoperative period following a successful *** changes appear to stabilise at 3 months,and it would be prudent to defer the prescription of new glasses until this *** sequential cataract surgery is to be performed,toric intraocular lenses can be a useful option for astigmatic correction.

关键词： Filtration surgery Trabeculectomy Astigmatism Refractive outcome

NUMERiCAL SiMULATiON OF TEMPERATURE FiELD DURiNG MAGNETiC FiELD QUENChiNG

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 773-776页

作者： M. h. Liu Z.h. Li X.Q. yu J.R. Chen Kunming University of Science ＆ Technology Kunming 650093 China hebei University of Science ＆ Technology Shijiazhuang 050018 China

Based on the theories of the heat transfer, the principle of phase transformation and the theory of electric and magnetic field, the mathematical model of transient temperature field involving phase transformation during magnetic field quenching is established. The heat exchange equation including magnetic field is founded. The finite element equation is set up. The distributing of transient temperature on the coupling effects of heat and magnetism is obtained. With test and measurement, the results show that after magnetic field quenching, cooling velocity is decreased, cooling curve is flatten out, and the hardness is slightly raised.

关键词： magnetic field quenching specific heals abrupt change non-linear heatconduction equation finite element equation

An Overview of the Expert Consensus on the Prevention and Treatment of Gaming Disorder in China(2019 Edition)

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Neuroscience Bulletin 2020年第7期36卷 825-828页

作者： yu-Tao Xiang yu Jin Ling Zhang Lu Li Gabor S.Ungvari Chee h.Ng Min Zhao Wei hao Unit of Psychiatry Institute of Translational MedicineFaculty of Health SciencesUniversity of MacaoMacao 999078China Center for Cognition and Brain Sciences University of MacaoMacao 999078China The National Clinical Research Center for Mental Disorders&Beijing Key Laboratory of Mental Disorders Beijing Anding Hospital&the Advanced Innovation Center for Human Brain ProtectionCapital Medical UniversitySchool of Mental HealthBeijing 100088China The Affiliated Brain hospital of Guangzhou Medical University(Guangzhou huiai hospital) Guangzhou 510370China 不详

Gaming disorder has gained considerable attention worldwide,including in China[1],where epidemiological surveys have found that its prevalence is as high as 17%[2].The Bureau of Disease Control and Prevention run by the National health and health Commission in China recently released an expert consensus[2]that systematically describes the definition,clinical presentation,assess-assessment,diagnosis,treatment,rehabilitation,and related areas of gaming disorder.

关键词： gained Expert diagnosis