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Theoretical Modelling of Metallurgical Defect Closing-Up Processes During Forming a Forging

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Journal of Iron and steel Research International 2013年第9期20卷 111-116页

作者： G Banaszek s Berski H Dyja A Kawaek Czestochowa University of Technology

Computer modelling using an FEM-based program, i.e. Forge 2008, was carried out. Laboratory model-ling of the process of free hot forging in shaped anvils was conducted to close up metallurgical defects. Results ob- tained from the simulation modelling were processed by using a commercial statistical package, i.e. statistica 6.0 PL. The influence of the anvil shape and main parameters of the forging process on closing up metallurgical defects were determined. On the basis of the investigation carried out, the optimal values of main forging technologieal parameters and suitable groups of anvils to be used in particular forging tages are proposed for the elimination of metallurgical defects.

关键词： shape anvil metallurgical defect free forging objective function FEM

The human gut sterolbiome:bile acid-microbiome endocrine aspects and therapeutics

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Acta Pharmaceutica sinica B 2015年第2期5卷 99-105页

作者： Jason M.Ridlon Jasmohan s.Bajaj Department of Microbiology and Immunology Virginia Commonwealth University McGuire VA Medical Center Division of Gastroenterology Hepatology and Nutrition Virginia Commonwealth University

The human body is now viewed as a complex ecosystem that on a cellular and gene level is mainly prokaryotic. The mammalian liver synthesizes and secretes hydrophilic primary bile acids, some of which enter the colon during the enterohepatic circulation, and are converted into numerous hydrophobic metabolites which are capable of entering the portal circulation, returned to the liver, and in humans,accumulating in the biliary pool. Bile acids are hormones that regulate their own synthesis, transport, in addition to glucose and lipid homeostasis, and energy balance. The gut microbial community through their capacity to produce bile acid metabolites distinct from the liver can be thought of as an "endocrine organ"with potential to alter host physiology, perhaps to their own favor. We propose the term "sterolbiome" to describe the genetic potential of the gut microbiome to produce endocrine molecules from endogenous and exogenous steroids in the mammalian gut. The affinity of secondary bile acid metabolites to host nuclear receptors is described, the potential of secondary bile acids to promote tumors, and the potential of bile acids to serve as therapeutic agents are discussed.

关键词： sterolbiome Gut microbiome Bile acids Metabolite Therapeutic agent

Dispersion and Damage of Carbon Nanotubes in Carbon Nanotube/7055Al Composites During High-Energy Ball Milling Process

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Acta Metallurgica sinica(English Letters) 2021年第2期34卷 196-204页

作者： s.Bi B.L.Xiao Z.H.Ji B.s.Liu Z.Y.Liu Z.Y.Ma shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China school of Material science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China AVIC Manufacturing Technology Institute Beijing 100024China

High-energy ball milling(HEBM)combined with powder metallurgy route was used to fabricate carbon nanotube(CNT)reinforced 7055 Al *** powder morphology evolution processes(HEBM-1 and HEBM-2)were designed to investigate the dispersion and damage of CNTs during HEBM ***-1 evolution process involved powder fl attening,cold-welding and fracture,while HEBM-2 evolution process consisted of powder fl attening and *** HEBM-1,the repetitive fracture and cold-welding process was effective for dispersing ***,the powder fl attening process in HEBM-2 was unsuccessful in dispersing CNTs due to two reasons:(1)the thickness of fl aky Al powders exceeded the critical value,and(2)the clustered CNTs embedded in fl aky Al powders could not be *** of the broadening of D band and the appearance of a new defect-related D’band,product of I D/I G and full width half maximum of D band,rather than I D/I G,was used to evaluate the actual damage of *** indicates that the damage of CNTs was severe in powder fl attening and fracture stages,while the damage of CNTs was small in powder cold-welding stage.

关键词： Metal matrix composites Carbon nanotubes Powder evolution Dispersion and damage Powder metallurgy

Cadmium sulfide cage photocatalysis coupled electroactive biofilm for synergistic promotion of tetracycline degradation and electricity production

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Journal of Materials science & Technology 2023年第35期166卷 86-97页

作者： Z.s.Yuan J.X.Zou X.L.Zhao J.Y.shi C.s.Guo M.Yan school of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China

Tetracycline(TC)as a common broad-spectrum antibiotic,has been frequently detected in soil and sur-face *** becomes a great threat to the ecological ***,a device of photocatalysis as-sisted microbial fuel cell(photo-MFC)was constructed for TC degradation and energy *** this photo-MFC,cadmium sulfide(Cds)cage photocatalysis can degrade most of TC in a short *** the Co_(3)O_(4)@C-CC(carbonization and calcination of the ZIF-67 precursor in-situ grown on the carbon cloth(CC))bioanode degrades the rest of TC as well as the photocatalytic products,thus improving the *** co-existence of photocatalysis with bioanode changes the microbial community structure of the *** dominant phylum is Geobacter(60.2%)in normal MFC while that in photo-MFC are Pro-teobacteria(43.5%)and Geobacter(33.2%).Therefore,the synergistic effect of photocatalytic degradation and biodegradation achieves a chemical oxygen demand(COD)removal of 98.6%,which is higher than that of normal MFC(77.6%)or single Cds cage photocatalysis(23.8%).In addition,the photogenerated electrons can be transferred to the cathode,which reduces their combination with holes and increases the electricity generation of MFC,achieving a maximum power density of 3.37 W/m^(2).After degradation,the effluent with 200 mg L^(−1) TC exhibits no visible ***,electrochemical test,finite-difference time-domain(FDTD),density functional theory(DFT)calculation and the free radical trapping experiments verify the possible mechanisms of photocatalytic degradation in this *** strat-egy paves a new way for low energy consumption removal and energy recovery of organic pollutants.

关键词： Photo-MFC Cds cage Tetracycline degradation Mineralization Electricity production

Review of research and application of evaporative cooling in preservation of fresh agricultural produce

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International Journal of Agricultural and Biological Engineering 2014年第5期7卷 85-102页

作者： M.C.Ndukwu s.I.Manuwa Department of Agricultural and Bio-resources Engineering Michael Okpara University of AgricultureUmudike Umuahia Abia StateNigeria Department of Agricultural Engineering Federal University of Technology AkureP.M.B.704 AkureOndo StateNigeria

Extensive review of evaporative coolers for the preservation of fresh agricultural produce in some countries was *** of the designs employ mainly direct evaporative cooling methods which are simple but with lower thermal performance,and can only be used for short term storage of agricultural produce with moderate respiratory *** into novel technologies in evaporative cooling systems which can improve the cooling performances,such as membrane air treatments,dew point type and heat pipe type heat exchanger in indirect/direct evaporative cooling application,and their feasibilities in agricultural storage are either absent or *** kinds of materials especially agricultural residues have been used for air water contact in evaporative cooling in different climates,but most of the analyses focused on effect of air flow rate and pad thickness on the cooling effectiveness,and the energy efficiency and evaporation loss of these materials in most cases were not evaluated or *** paper highlights the prospects and constraints of commercialization and marketing of evaporative coolers in some developing countries,and the general weakness in researches and the ways forward in new area of research and development are concluded.

关键词： agricultural products evaporative cooling passive coolers active coolers pad materials

Dynamics of Entanglement in Qubit-Qutrit with x-Component of DM Interaction

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Communications in Theoretical Physics 2016年第3期65卷 278-284页

作者： Kapil K.sharma s.N.Pandey Department of Physics Motilal Nehru National Institute of Technology

In this present paper,we study the entanglement dynamics in qubit A-qutrit B pair under x component of Dzyaloshinshkii-Moriya interaction(D_x)by taking an auxiliary qubit ***,we consider an entangled qubit-qutrit pair initially prepared in two parameter qubit-qutrit states and one auxiliary qubit prepared in pure state interacts with the qutrit of the pair through DM *** trace away the auxiliary qubit and calculate the reduced dynamics in qubit A-qutrit B pair to study the influence of the state of auxiliary qubit C and D_x on *** find that the state(probability amplitude)of auxiliary qubit does not influence the entanglement,only D_x influences the *** phenomenon of entanglement sudden death(EsD)induced by D_x has also been *** also present the affected and unaffected two parameter qubit-qutrit states by D_x.

关键词： entanglement dynamics qubit-qutrit DM interaction EsD

study of cyanide removal from contaminated water using zinc peroxide nanomaterial

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Journal of Environmental sciences 2017年第5期29卷 76-85页

作者： Himani Uppal s. swarupa Tripathy sneha Chawla Bharti sharma M.K. Dalai s.P. singh sukhvir singh Nahar singh CsIR-National Physical Laboratory New Delhi 110012 India Electronic science Kurukshetra University Kurukshetra Haryana 136119 India Academy of scientific and Innovative Research (AcsIR) India

The present study highlights the potential application of zinc peroxide （ZnO2） nanomaterial as an efficient material for the decontamination of cyanide from contaminated water. A process patent for ZnO2 synthesis has been granted in United states of America （Us Patent number 8,715,612; May 2014）, south Africa, Bangladesh, and India. The ZnO2 nanomaterial was capped with polyvinylpyrrolidone （PVP） to control the particle size. The PVP capped ZnO2 nanomaterial （PVP-ZnO2） before and after adsorption of cyanide was characterized by scanning electron microscope, transmission electron microscope, X-ray diffractorneter, Fourier transform infrared spectroscopy and time of flight-secondary ion mass spectrom- etry. The remaining concentration of cyanide after adsorption by PVP-ZnO2 was determined using ion chromatograph. The adsorption of cyanide over PVP-ZnO2 was also studied as a function of pH, adsorbent dose, time and concentration of cyanide. The maximum removal of cyanide was observed in pH range 5.8-7.8 within 15 rain. The adsorption data was fitted to Langmuir and Fruendlich isotherm and it has been observed that data follows both the isotherms and also follows second order kinetics.

关键词： Cyanide Zinc peroxide Adsorption Ion chromatograph

slip and induced magnetic field effects on peristaltic transport of Johnson-segalman fluid

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Applied Mathematics and Mechanics(English Edition) 2012年第8期33卷 1035-1048页

作者： T.HAYAT s.NOREEN A.ALsAEDI Department of Mathematics Quaid-I-Azam UniversityIslamabad 44000Pakistan Department of Mathematics Comsats Institute of Information TechnologyAttock 43600Pakistan Department of Mathematics Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia

The peristaltic flow of a Johnson-segalman fluid in a planar channel is investigated in an induced magnetic field with the slip condition. The symmetric nature of the flow in a channel is utilized. The velocity slip condition in terms of shear stresses is considered. The mathematical formulation is presented, and the equations are solved under long wavelength and low Reynolds number approximations. The perturbation solutions are established for the pressure, the axial velocity, the micro-rotation component, the stream function, the magnetic-force function, the axial induced magnetic field, and the current distribution across the channel. The solution expressions for small Weissenberg numbers are derived. The flow quantities of interest are sketched and analyzed.

关键词： induced magnetic field slip condition Johnson-segalman fluid

Heterospecific interactions and the proliferation of sexually dimorphic traits

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Current Zoology 2012年第3期58卷 453-462页

作者： Karin s. PFENNIG Allen H. HURLBERT Department of Biology University of North Carolina Chapel Hill Chapel Hill NC 27599-3280

sexual selection is expected to promote speciation by fostering the evolution of sexual traits that minimize reproductive interactions among existing or incipient species. In species that compete for access to, or attention of, females, sexual selec- tion fosters more elaborate traits in males compared to females. If these traits also minimize reproductive interactions with het- erospecifics, then species with enhanced risk of interactions between species might display greater numbers of these sexually di- morphic characters. We tested this prediction in eight families of North American birds. In particular, we evaluated whether the number of sexually dimorphic traits was positively associated with species richness at a given site or with degree of sympatry with congeners. We found no strong evidence of enhanced sexual dimorphism with increasing confamilial species richness at a given site. We also found no overall relationship between the number of sexually dimorphic traits and overlap with congeners across these eight families. However, we found patterns consistent with our prediction within Anatidae （ducks, geese and swans） and, to a lesser degree, Parulidae （New World warblers）. Our results suggest that sexually selected plumage traits in these groups potentially play a role in reproductive isolation [Current Zoology 58 （3）： 453--462, 2012].

关键词： speciation Reproductive character displacement sexual selection species recognition Reinforcement