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Heavy metals and PAHs in Sewage Sludge from Twelve Wastewater Treatment Plants in Zhejiang Province

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Biomedical and Environmental Sciences 2008年第4期21卷 345-352页

作者： c. m. TIENTcHEN college of Environmental and Resource Sciences Zhejiang University

Objective To investigate the heavy metals （Hms） and polycyclic aromatic hydrocarbons （PAHs） in sludge of twelve wastewater treatment plants （WWTPs） in Zhejiang province of china, and to assess their potential for land application. methods Sludge was collected from 12 WWTPs within the province. Gc-mS and AAS were used to measure PAHs and Hms contents in sludge. Results concentrations of Hms in most of the sludge samples were below the regulatory limits for the sludge to be used in agriculture in china with the exception of Zn in 2 sludge samples and cd in 1 sample. All 16 PAHs, targeted by the USEPA agency, were found in the sludge from the twelve plants with a total concentration ranging from 33.73 mg kg^-1 to 82.58 mg kg^-1 （dry weight, d.w.）. The levels of Σ9 PAHs varied from 13.87 mg kg^-1 to 61.86 mg kg^-1 （d.w.） in the sludge, far exceeding the limitation value recommended by the Europe Union. The concentration and composition of PAHs in sewage sludge varied and depended mainly on the quantity and type of industrial wastewater accepted by the WWTPs. A significant relationship between the proportion of industrial wastewater received by WWTPs and the total content of 16 PAHs in the sludge was observed. conclusion PAHs have become one of the primary pollutants in sludge of Zhejiang WWTPs instead of Hms. It is, therefore, essential to reduce the contents of PAHs before the sludge can be used in agriculture through proper treatment.

关键词： Sludge Heavy metal chemical Fractions Polycyclic aromatic hydrocarbons contribution

Polycrystalline diamond mini-cubes for sawing applications

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金刚石与磨料磨具工程 2008年第S1期28卷 83-87页

作者： sung James c. chang Kuen-liang Tso Pei-lum Hsu Kai-hung sung michael KINIK company 64Chung-San Rd.Ying-Kuo National Taiwan University National Taipei University of Technology PmE Dept.National Tsing Hua University Advanced Diamond Solutions Inc.351 King Street Suite 813San FranciscoCA 94158U.S.A.

Diamond grits are indispensable for sawing granite or *** year about 1 000 tons of diamond grits are consumed for such *** all cases,mono crystalline diamond is ***, polycrystalline grits(polygrits) are generally better performed than mono grits as *** example,poly grits of cubic boron nitride(***(?) cBN-550 of Diamond Innovations) can cut faster and they last longer than mono grits(***(?) cBN-500). Polygrits of alumina(***(?) of 3m) also out perform by far glassy grits(*** alumina).For diamond superabrasives,micron polygrits formed by shock waves may polish as fast as mono grits of the same size,but without causing as much scratches due to the presence of smaller sintered *** improved performance of poly grits is attributed to their ability to micro chipping that renews the sharp cutting corners from time to *** contrast,mono grits tend to round off at low cutting force or macro fracture at high cutting force,so they may lose the cutting ability rapidly. For sawing granite with mesh sizes 40/50 or coarser,poly grits of diamond have not been available until *** this research,we have made polygrits in mini cube with sizes of 18/20,20/25,and 30/*** grinders and wire saws were made by brazing both mono grits and polygrits on steel *** performance on granite demonstrated that grinding speed was faster with turbo grinder,and the surface finish was smoother with wire saw for poly grits than mono ones. Polygrits and mono grits of diamond were mixed for comparison(upper left).Polygrits of mini cubes were brazed on the pearl of a wire saw(upper right).mono diamond grits were brazed on a turbo grinder(bottom diagrams ).

关键词： granite sawing diamond grits polygrits turbo grinder wire saw

The impact of alpha-fetoprotein(AFP),child-turcotte-pugh(cTP)score and disease staging on the survival of hepatocellular carcinoma(Hcc)patients:a retrospective cohort from single oncology center

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Oncology Research 2025年第1期33卷 149-160页

作者： NASSER mULLA YOUSEF KATIB ASIm m.ALmUGHAmSI DUAA S.ALKHAYAT mOHAmED mOSAAD SAmIR T.ALFOTIH RAWAN ALAOFI Department of Internal medicine Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Radiology Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Surgery Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Endemic and Infectious Diseases Suez Canal UniversityIsmailia41522Egypt King Salman bin Abdulaziz medical city Madinah42311Saudi Arabia Prince mohammed Bin Abdulaziz Hospital Madinah41511Saudi Arabia

Background:Hepatocellular carcinoma(Hcc)is the most common cause of cancer-related death in Saudi *** study aimed to investigate the patterns of Hcc and the effect of TNm staging,Alfa-fetoprotein(AFP),and child-Turcotte Pugh(cTP)on patients’overall survival(OS).methods:A retrospective analysis was conducted on 43 Hcc patients at a single oncology center in Saudi Arabia from 2015 to *** patients had to fulfill one of the following criteria:(a)a liver lesion reported as definitive Hcc on dynamic imaging and/or(b)a biopsy-confirmed ***:The mean patient age of all Hcc cases was 66.8 with a male-to-female ratio of 3.3:*** patients were stratified into two groups:viral Hcc(n=22,51%)and non-viral Hcc(n=21,49%).Among viral-Hcc patients,55%were due to HBV and 45%due to *** was diagnosed in 79%of *** and sex did not significantly statistically differ in OS among viral and non-viral Hcc patients(p-value>0.05).About 65%of patients had tumor size>5 cm during the diagnosis,with a significant statistical difference in OS(p-value=0.027).AFP was>400 ng/ml in 45%of the *** was a statistically significant difference in the OS in terms of AFP levels(p-value=0.021).A statistically significant difference was also observed between the cTP score and OS(p-value=0.02).cTP class B had the longest *** was the most common treatment provided to Hcc patients followed by sorafenib *** was a significant statistical difference in OS among viral and non-viral Hcc patients(p-value=0.008).conclusions:The most common predictors for OS were the underlying cause of Hcc,AFP,and tumor *** having non-viral etiology,a tumor size>5 cm,an AFP>400 ng/mL,and a cTP score class c were all negatively associated with OS.

关键词： Hepatocellular carcinoma Pattern Alpha-fetoprotein(AFP) child-turcotte-pugh Progression free survival

Ion acoustic shock and periodic waves through Burgers equation in weakly and highly relativistic plasmas with nonextensivity

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Plasma Science and Technology 2017年第1期19卷 7-19页

作者： m G HAFEZ N c ROY m R TALUKDER m HOSSAIN ALI Department of of Applied mathematics University of Rajshahi Rajshahi-6205 Bangladesh Department of mathematics Chittagong University of Engineering and Technology Chittagong-4349Bangladesh Plasma Science and Technology Lab Department of Applied Physics and Electronic EngineeringUniversity of Rajshahi Rajshahi-6205 Bangladesh

A comparative study is carried out for the nonlinear propagation of ion acoustic shock waves both for the weakly and highly relativistic plasmas consisting of relativistic ions and qdistributed electrons and *** Burgers equation is derived to reveal the physical phenomena using the well known reductive perturbation *** integration of the Burgers equation is performed by the（G￠/G）-expansion *** effects of positron concentration,ion–electron temperature ratio,electron–positron temperature ratio,ion viscosity coefficient,relativistic streaming factor and the strength of the electron and positron nonextensivity on the nonlinear propagation of ion acoustic shock and periodic waves are presented graphically and the relevant physical explanations are provided.

关键词： electron-positron-ion plasmas ion acoustic shock and periodic waves weakly and highly relativistic effects Burgers equation

SURFAcE FINITE ELEmENTS FOR PARABOLIc EQUATIONS

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Journal of computational mathematics 2007年第4期25卷 385-407页

作者： G. Dziuk c.m. Elliott Abteilung für Angewandte mathematik University of Freiburg Hermann-Herder-Straβe 10 D-79104Freiburg i. BrGermany Department of mathematics University of Sussex Falmer Brighton BN1 9RF United Kingdom

In this article we define a surface finite element method （SFEm） for the numerical solution of parabolic partial differential equations on hypersurfaces F in R^n＋1. The key idea is based on the approximation of F by a polyhedral surface Гh consisting of a union of simplices （triangles for n = 2, intervals for n = 1） with vertices on Г. A finite element space of functions is then defined by taking the continuous functions on Гh which are linear affine on each simplex of the polygonal surface. We use surface gradients to define weak forms of elliptic operators and naturally generate weak formulations of elliptic and parabolic equations on Г. Our finite element method is applied to weak forms of the equations. The computation of the mass and element stiffness matrices are simple and straightforward. We give an example of error bounds in the case of semi-discretization in space for a fourth order linear problem. Numerical experiments are described for several linear and nonlinear partial differential equations. In particular the power of the method is demorrstrated by employing it to solve highly nonlinear second and fourth order problems such as surface Allen-cahn and cahn-Hilliard equations and surface level set equations for geodesic mean curvature flow.

关键词： Surface partial differential equations Surface finite element method Geodesic curvature Triangulated surface.

Improved continuous precipitation kinetics and tensile properties of extruded AZ80 alloy through {10-12} twin formation

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Journal of magnesium and Alloys 2023年第9期11卷 3323-3337页

作者： Hyun Ji Kim Sumi Jo sung Hyuk Park Department of materials Science and metallurgical Engineering Kyungpook National UniversityDaegu 41566the Republic of Korea

This study investigates the effect of{10-12}deformation twins on the continuous precipitation behavior of an extruded mg-8.0Al-0.5Zn-0.2mn(AZ80)alloy during *** extruded AZ80 alloy is compressed along the transverse direction to introduce{10-12}twins,followed by an aging treatment at 300℃.The extruded material exhibits a twin-free microstructure with low internal strain energy,whereas the pre-twinned material possesses abundant{10-12}twins and has high internal strain *** aging results reveal that the peak-aging time of the pre-twinned material(1 h)is one-eighth of that of the extruded material(8 h).Although mg_(17)Al_(12)continuous precipitates(cPs)are observed in both the peak-aged materials,these cPs are much smaller and more densely distributed in the pre-twinned material despite the significantly shorter aging *** cPs size in the peak-aged materials increases in the following order:twinned region in the pre-twinned material(0.47μm)matrix region in the pre-twinned material(1.71μm)matrix region in the extruded material(2.55μm).moreover,the cPs number density in the twinned region of the pre-twinned material is approximately 11 times higher than that in the matrix region of the extruded *** peak-aged pre-twinned material exhibits significantly higher tensile strength and ductility than the peak-aged extruded *** results demonstrate that the formation of{10-12}twins in the extruded AZ80 alloy substantially accelerates the static precipitation of cPs during aging at 300℃and improves the tensile properties of the peak-aged material.

关键词： AZ80 alloy {10-12}twin Aging continuous precipitation Tensile properties

Tagging major quantitative trait loci for sheath blight resistance in a rice variety, Jasmine 85

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chinese Science Bulletin 1999年第19期44卷 1783-1789页

作者： m.c.Rush Louisiana State University Baton RougeLAUSA70803

This study was conducted with a clonal F2 population of rice from a cross between Jasmine 85, a resistant variety, and Lemont, a susceptible cultivar. The rice plants belonging to each F2 clone were divided into two plots, which were put in two replicates, respectively. clonal parents were tested as controls. The plants were inoculated by short toothpicks incubat-

关键词： rice sheath blight major QTLs RFLP.

HIGH-TEmPERATURE OXIDATION OF FGH96 P/m SUPERALLOY

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Acta metallurgica Sinica(English Letters) 2007年第2期20卷 102-110页

作者： F.J. Liu m.c. Zhang J.X. Dong Y. W. Zhang School of materials Science and Engineering University of Science and Technology BeijingBeijing 100083 China central Iron and Steel Research Institute Beijing 100081 China

High temperature oxidation behaviors of FGH96 P/m superaUoy have been studied in air at temperatures ranging from 600 to 1000℃. By means of isothermal oxidation testing, X-ray diffraction, SEm （scanning electron microscopy）, and EDS （energy dispersive X-ray spectroscopy） analyses, the oxidation kinetics as well as the composition and morphology of scales were investigated. Thermodynamic calculations were used to explain the oxidation mechanism. The results showed that as the oxidation temperature increased, the oxidation rate, the scale thickness, and scale spallation increased. FGH96 P/m superalloy exhibits good oxidation resistance at temperature below 800℃. The oxidation kinetics follows an approximately parabolic rate law, and the oxide layer was mainly composed of cr2O3 TiO2 and a little amount of Nicr2O4. The oxidation is controlled by the transmission of chromium. titanium, and oxygen through the oxide scale.

关键词： FGH96 P/m superalloy high temperature oxidation oxide scale

State of the Art on micromilling of materials,a Review

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Journal of materials Science & Technology 2012年第8期28卷 673-685页

作者： m.A.cmara J.c. campos Rubio A.m. Abro J.P. Davim Department of mechanical Engineering Universidade Federal de Minas GeraisAv.Ant onio Carlos6627-Pampulha Belo Horizonte MGCEP:31.270-901Brazil Department of mechanical Engineering University of AveiroCampus Universitrio de Santiago3810-193AveiroPortugal

The trend towards miniaturization has increased dramatically over the last decade, especially within the fields concerned with bioengineering, microelectronics, and aerospace. micromillin8 is among the principal manu- facturing processes which have allowed the development of components possessing micrometric dimensions, being used to the manufacture of both forming tools and the final product. The aim of this work is to present the principal aspects related to this technology, with emphasis on the work material requirements, tool ma- terials and geometry, cutting forces and temperature, quality of the finished product, process modelling and monitoring and machine tool requirements. It can be noticed that size effect possesses a relevant role with regard to the selection of both work material （grain size） and tooling （edge radius）. Low forces and temper- ature are recorded during micromillin8, however, the specific cutting force may reach high values because of the ploughing effect observed as the uncut chip thickness is reduced. Finally, burr formation is the principal concern with regard to the quality of the finished part.

关键词： micro-milling micromachining Size effect miniaturization