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基于粗颗粒动态演化过程的高铁填料振动压实机理研究

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岩土工程学报 2024年第4期46卷 803-813页

作者：谢康陈晓斌尧俊凯李泰灃王业顺邓志兴吕鑫龙中南大学土木工程学院湖南长沙410075 中国铁道科学研究院集团有限公司铁道建筑研究所北京100081

为了揭示高铁粗粒土填料振动压实机理,以典型的高铁基床表层级配碎石填料为研究对象,首先基于自行研制的大型振动压实仪,建立连续干密度ρ_(rd)、动刚度Krb以及修正地基系数K20的压实质量评估体系;然后利用X-CT对压实过程中的级配碎石... 详细信息

为了揭示高铁粗粒土填料振动压实机理,以典型的高铁基床表层级配碎石填料为研究对象,首先基于自行研制的大型振动压实仪,建立连续干密度ρ_(rd)、动刚度Krb以及修正地基系数K20的压实质量评估体系;然后利用X-CT对压实过程中的级配碎石进行扫描,从粗颗粒动态演化角度揭示级配碎石的压实机制。研究结果表明:整个压实过程中,不同土体类型的级配碎石ρ_(rd)均呈现出急速上升-缓慢上升的趋势,而Krb和K20却呈现出急速上升-缓慢下降的趋势。进一步,提出压实嵌锁点Tlp以量化出级配碎石的压实性能拐点特征。振动压实过程中当60%的粗颗粒长轴趋于水平排布时(处于Tlp状态),即呈现出振动压实稳定态;而后进一步压实,易导致粗颗粒发生以表面研磨为主的破碎现象,破坏骨架稳定性,降低压实性能。最终通过离散元模拟验证该机制的正确性。研究成果可从细观层面揭示振动压实机理,为高铁智能碾压质量评估提供新的方法。

关键词：高铁路基级配碎石压实机理 X-CT 动态演化量化表征

On the Time Fractional Modulation for Electron Acoustic Shock Waves

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Chinese Physics letters 2017年第3期34卷 86-89页

作者： H.g.Abdelwahed E.K.El-Shewy A.A.Mahmoud College of Science and Humanity Studies Al-Kharj Department of PhysicsPrince Sattam Bin Abdulaziz University Theoretical Physics group Department of PhysicsFaculty of ScienceMansoura University

Nonlinear features of electron-acoustic shock waves are studied. The Burgers equation is derived and converted to the time fractional Burgers equation by Agrawal＇s method. Using the Adomian decomposition method, the shock wave solutions of the time fractional Burgers equation are constructed. The effect of time fractional parameter on the shock wave properties in auroral plasma ＆ investigated.

关键词： On the Time Fractional Modulation for Electron Acoustic Shock Waves

Sodium glucose co-transporter 2 inhibition reduces succinate levels in diabetic mice

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World Journal of gastroenterology 2020年第23期26卷 3225-3235页

作者： lakshini Y Herat Natalie C Ward Aaron l Magno Elizabeth P Rakoczy Marcio g Kiuchi Markus P Schlaich Vance B Matthews School of Biomedical Sciences Dobney Hypertension CentreRoyal Perth Hospital UnitUniversity of Western AustraliaPerth 6000Australia Faculty of Health and Medical Sciences University of Western AustraliaCrawley 6009Australia Faculty of Health Sciences School of Public HealthCurtin UniversityBentley 6102Australia Research Centre Royal Perth HospitalPerth 6000Australia Department of Molecular Ophthalmology University of Western AustraliaCrawley 6009Australia Dobney Hypertension Centre School of MedicineRoyal Perth Hospital UnitUniversity of Western AustraliaPerth 6000Australia Department of Cardiology and Department of Nephrology Royal Perth HospitalPerth 6000Australia

BACKgROUND Type 1 diabetes(T1D) is associated with major chronic microvascular complications which contribute significantly to diabetes associated *** protein primarily responsible for glucose reabsorption in the kidney is sodium glucose co-transporter 2(SglT2). Presently, SglT2 inhibitors are widely used in diabetic patients to improve blood glucose levels and prevent cardiovascular and renal complications. given the broad therapeutic application of SglT2 inhibitors, we hypothesised that SglT2 inhibition may exert its protective effects via alterations of the gut microbiome and tested this in a type 1 diabetic mouse model of diabetic *** To determine whether the treatment with two independent SglT2 inhibitors affects gut health in a type 1 diabetic mouse *** The SglT2 inhibitors empagliflozin or dapagliflozin(25 mg/kg/d) or vehicle dimethylsulfoxide(DMSO) were administered to C57 Bl/6 J, Akita, Kimba and Akimba mice at 10 wk of age for 8 wk via their drinking water. Serum samples were collected and the concentration of succinate and the short chain fatty acid(SCFA) butyric acid was measured using gas chromatography-mass spectrometry. Enzyme-linked immunosorbent assay(ElISA) was performed to determine the concentration of insulin and leptin. Furthermore, the norepinephrine content in kidney tissue was determined using ElISA. Pancreatic tissue was collected and stained with haematoxylin and eosin and analysed using brightfield *** Due to the presence of the Akita allele, both Akita and Akimba mice showed a reduction in insulin production compared to C57 Bl/6 J and Kimba ***, Akita mice also showed the presence of apoptotic bodies within the pancreatic islets. The acinar cells of Akita and Akimba mice showed swelling which is indicative of acute injury or pancreatitis. After 8 wk of SglT2 inhibition with dapagliflozin, the intermediate metabolite of gut metabolism known as succinate was significantly reduced

关键词： Sodium glucose co-transporter inhibitors Sodium glucose co-transporter 2 Diabetes Diabetic retinopathy Mouse gut microbiota Empagliflozin Dapagliflozin Succinate Akimba

ElECTROREDUCTION　OF　Zn^2＋　AND　Ni^2＋　AND　Cu^2＋　IN　UREA－CHlORIDES　MElT

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中国有色金属学会会刊：英文版 1996年第2期6卷 41-44,52页

作者： liu P. Yang Q. liu g. Department of Chemistry Zhongshan University Guangzhou 510275 China

ＥＬＥＣＴＲＯＲＥＤＵＣＴＩＯＮＯＦＺｎ２＋ＡＮＤＮｉ２＋ＡＮＤＣｕ２＋ＩＮＵＲＥＡ－ＣＨＬＯＲＩＤＥＳＭＥＬＴＬｉｕＰｅｎｇ；ＹａｎｇＱｉｑｉｎ；ＬｉｕＧｕａｎｋｕｎ(ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，Ｚ... 详细信息

ＥＬＥＣＴＲＯＲＥＤＵＣＴＩＯＮＯＦＺｎ２＋ＡＮＤＮｉ２＋ＡＮＤＣｕ２＋ＩＮＵＲＥＡ－ＣＨＬＯＲＩＤＥＳＭＥＬＴＬｉｕＰｅｎｇ；ＹａｎｇＱｉｑｉｎ；ＬｉｕＧｕａｎｋｕｎ(ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＺｈｏｎｇｓｈａｎＵ?..

关键词： urea-chlorides melt, electroreduction of Zn￣(2+), Ni￣(2+) and Cu￣(2+) diffusion coefficient transfer coefficient

lIVESTOCK PRODUCTION PlANNINg UNDER ENVIRONMENTAl RISKS AND UNCERTAINTIES

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Journal of Systems Science and Systems Engineering 2006年第4期15卷 399-418页

作者： günther FISCHER Tatiana ERMOlIEVA Yuri ERMOlIEV Harrij van VElTHUIZEN International Institute for Applied Systems Analysis Schlossplatz 1 A-2361 Laxenburg Austria

In this paper we demonstrate the need for risk-adjusted approaches to planning expansion of livestock production. In particular, we illustrate that under exposure to risk, a portfolio of producers is needed where more efficient producers co-exist and cooperate with less efficient ones given that the latter are associated with lower, uncorre, lated or even negatively correlated contingencies. This raises important issues of cooperation and risk sharing among diverse producers. For large-scale practical allocation problems when information on the contingencies may be disperse, not analytically tractable, or be available on aggregate levels, we propose a downscaling procedure based on behavioral principles utilizing spatial risk preference structure, It allows for estimation of production allocation at required resolutions accounting for location specific risks and suitability constraints. The approach provides a tool for harmonization of data from various spatial levels. We applied the method in a case study of livestock production allocation in China to 2030.

关键词： Spatial production allocation sequential downscaling cross-entropy maximum likelihood risks and uncertainties.

An investigation of roof runoff during rain events at the Royal Military College of Canada and potential discharge to lake Ontario

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Journal of Environmental Sciences 2011年第7期23卷 1072-1078页

作者： David g. Kelly Ron D. Weir Steven D. White Analytical Sciences group & SlOWPOKE-2 Facility at RMC Department of Chemistry and Chemical Engineering Royal Military College of Canada 11 General Crerar Crescent

The Royal Military College of Canada, located on the north eastern shore of lake Ontario, possesses an abundance of copper roofs and lacks surface water treatment prior to discharge into lake Ontario. Rainwater, roof runoff and soil samples were collected and analyzed for copper and other parameters. Copper was consistently detected in runoff samples with average concentrations of 3200 ± 2100 μg/l. Multivariable linear regression analysis for a dependant copper runoff concentration yielded an adjusted R 2 value of 0.611, based on an independent variable model using minimum temperature, maximum temperature, total precipitation, and wind speed. lake water samples taken in the vicinity of storm water outfalls draining areas with copper roofs ranged from 2.0 to 40 μg/l copper. Such data exceed the 2.0 μg/l Canadian Water Quality guidelines for the Protection of Aquatic life as outlined by the Canadian Council of Ministers of the Environment （CCME）. Analysis of raw, filtered and digested forms suggested that the majority of copper present in runoff and lake water samples was in a dissolved form. The majority of soils taken in this study displayed copper concentrations below the 63 μg/g CCME residential/parkland land use limits. These findings suggested that ion exchange processes between runoff water and soil do not occur to a sufficient extent to elevate copper levels in soil. It may therefore be concluded that the eventual fate of copper, which is not discharged via storm water outfalls, is lost to the water table and lake Ontario through the sub-soil.

关键词： copper roof runoff lake Ontario Canadian water quality guidelines for the protection of aquatic life

Free convection of nanofluid filled enclosure using lattice Boltzmann method (lBM)

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Applied Mathematics and Mechanics(English Edition) 2013年第7期34卷 833-846页

作者： M.SHEIKHOlESlAMI M.gORJI-BANDPY g.DOMAIRRY Department of Mechanical Engineering Babol Noshirvani University of Technology

The lattice Boltzmann method （lBM） is used to examine free convection of nanofluids. The space between the cold outer square and heated inner circular cylinders is filled with water including various kinds of nanoparticles： TiO2, Ag, Cu, and A1203. The Brinkman and Maxwell-garnetts models are used to simulate the viscosity and the effective thermal conductivity of nanofluids, respectively. Results from the performed numerical analysis show good agreement with those obtained from other numerical meth- ods. A variety of the Rayleigh number, the nanoparticle volume fraction, and the aspect ratio are examined. According to the results, choosing copper as the nanoparticle leads to obtaining the highest enhancement for this problem. The results also indicate that the maximum value of enhancement occurs at λ =2.5 when Ra = 106 while at A = 1.5 for other Rayleigh numbers.

关键词： lattice Boltzmann method (lBM) nanofluid natural convection concentric annular cavity

STUDY OF RAY IRRADIATION ON DIAMOND-lIKE CARBON FIlMS

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Acta Metallurgica Sinica(English letters) 2002年第1期15卷 26-32页

作者： g.A. liu T.M. Wang E.Q Dept. of Appl. Phy. Southwest Jiaotong Univ. Chengdu 610031 China

Diamond-like carbon (DlC) films have been deposited on glass substrates usingradio-frequency (rf) plasma deposition method. gamma -ray, ultraviolet (UV) ray were used toirradiate the DlC films. Raman spectroscopy and infrared (IR) spectroscopy were use to characterizethe changing characteristics of SP^3 C-H bond and hydrogen content in the films due to theirradiations. The results show that, the damage degrees induced by the UV ray on the SP^3 C-H bondsare much stronger than that by the gamma -ray. When the irradiation dose of gamma -ray reaches 1 OX10^4 gy, the SP^3 C-H bond reduces about 50 percent in number. The square electrical resistance ofthe films is reduced due to the irradiation of UV ray and this is caused by severe oxidation of thefilms. By using the results on optical gap of the films and the fully constrained network theory,the hydrogen content in the as-deposited films is estimated to be l0-25at. percent.

关键词： diamond-like carbon film gamma -ray irradiation ultraviolet rayirradiation SP^3 C-H bond infrared transmittance

The number of intracorneal ring segments in asymmetric and central cones

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Eye and Vision 2021年第1期8卷 83-91页

作者： Canan Asli Utine DenizcanÖzizmirliler Mustafa Kayabaşı Üzeyir günenç Department of Ophthalmology Faculty of MedicineDokuz Eylul UniversityMithatpasa cadNo:1606 InciraltıKampusuBalcova35330 IzmirTurkey Izmir Biomedicine and genome Center IzmirTurkey

Background:To compare the results of single versus double intracorneal ring segment(ICRS)(KeraRing)implantation in keratoconus with respect to different cone ***:Twenty-two eyes of 18 patients with totally asymmetric cones(20-80%or 0-100%distribution along steep axis)were implanted with single ICRS(group 1),38 eyes of 32 patients with central or partially asymmetric cones(50-50%or 40-60%distribution along steep axis)were implanted with double ICRS(group 2),at a depth of 80%of the site of implantation,in channels created with femtosecond laser *** patients had uncorrected and corrected distance visual acuities(UDVA and CDVA,respectively)of≤0.3 Snellen ***:In both groups,patients had median UDVA and CDVA gain of 3 Snellen lines(P>0.05).Postoperative improvement in indices of vertical asymmetry and height decentration in group 1;simulated keratometry,corneal astigmatism and anterior corneal asphericity values in group 2 were greater(Pl of 10 eyes(45.5%)in group 1 were recommended double ring implantation by the manufacturer’s nomogram,but underwent single ICRS implantation and achieved visual,refractive,tomographic outcomes comparable to that in group 2,although corneal cylindrical correction was less and final topographic astigmatism was ***:Double ICRS implantation seems to be superior in terms of keratometry,corneal astigmatism and anterior corneal asphericity *** ICRS implantation in totally asymmetric cones seems to provide satisfactory visual,refractive and tomographic results,similar to double ICRS implantation in central and partially asymmetric cones,by inducing central shift of the cone.

关键词： Cone eccentricity Intracorneal ring segment implantation Keratoconus Nomogram