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Slope stability hazard management systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1695-1711页

作者： FREDLUND Delwyn g. Department of Civil Engineering University of Saskatchewan Saskatoon SK Canada MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310027 China

Weather-related geo-hazards are a major concern for both natural slopes and man-made slopes and embankments. government agencies and private companies are increasingly required to ensure that there is adequate protection of sloping sur- faces in order that interaction with the climate does not produce instability. Superior theoretical formulations and computer tools are now available to address engineering design issues related to the near ground surface soil-atmospheric interactions. An ex- ample is given in this paper that illustrates the consequences of not paying adequate attention to the hazards of slope stability prior to the construction of a highway in South America. On the other hand, examples are given from Hong Kong and China's Mainland where significant benefits are derived from putting in place a hazard slope stability management system. Some results from a hazard management slope stability study related to the railway system in Canada are also reported. The study took advantage of recent research on unsaturated soil behaviour and applied this information to real-time modelling of climatic conditions. The quantification of the water balance at the ground surface, and subsequent infiltration, is used as the primary tool for hazard level assessment. The suggested hazard model can be applied at either specific high risk locations or in a more general, broad-based manner over large areas. A more thorough understanding of unsaturated soil behaviour as it applies to near ground surface soils, along with the numerical computational power of the computer has made it possible for new approaches to be used in slope hazard management engineering.

关键词： Slope stability geo-hazards Highway Hazard Slope stability management system

Energy and momentum of rotating frames in tetrad gravity

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Chinese Physics B 2011年第10期20卷 101-111页

作者： gamal g L Nashed Mathematics Department Faculty of Science Ain Shams University

Within the framework of the tetrad formulation of general relativity theory, we compute the total energy and momentum of four rotating frames using the gravitational energy-momentum 3-form. We show how the effect of inertia always makes the total energy divergent. We use a natural regularization method to obtain physical values for the total energy of the system and show how it works on a number of explicit examples. We also show by calculation that inertia has no effect on the momentum components.

关键词： teleparallel gravity, energy-momentum WeitzenbSck connection, regularization telepar-allelism

Chemical Reduction of CO_2 to Different Products during Photo Catalytic Reaction on TiO_2 under Diverse Conditions:an Overview

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Journal of Natural gas Chemistry 2007年第3期16卷 217-226页

作者： g.R.Dey Radiation and Photochemistry Division Bhabha Atomic Research CentreTrombayMumbai 400085India

The chemical reduction of CO2 remains a challenge with respect to the reversal of the oxidative degradation of any organic materials. The conversion of CO2 into useful substances is essential in developing alternative fuels and various raw materials for different industries. This also aids in preventing the continuous rise in tropospheric temperature due to the green house effect of CO2. In this article an overview of the growth taken place so far in the field of CO2 chemical reduction is pre- sented. The discussion comprises of photochemical methods for the development of different products, viz. CO, CH3OH and CH4, through chemical reduction of CO2. This includes the use of photo catalysts, mainly TiO2, and the role of a hole scavenger （such as 2-propanol） for this purpose.

关键词： CO2 chemical reduction H2 CH4 CO TiO2 hole scavenger photolysis

A collaboration into research on nanoparticles (ACORN)

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Particuology 2009年第2期7卷 93-105页

作者： David g. Parker Chemistry Innovation The HeathRuncorn WA7 4QXUnited Kingdom

This paper describes the operation and outcome of one of the United Kingdom＇s largest multi-partner research activities in nanoparticles. The research covers the discovery and development of organic and inorganic crystals/nanoparticles, nanoparticle properties towards specific product applications. The research also encompassed bespoke measurement technology for nanoparticles and structure interactions. Significant research outcomes are summarised. The paper illustrates the advantages from industrially motivated research and value of collective action between a broad group of researchers in a nation.

关键词： Nanoparticles Nanoparticle manufacture Nanocrystals Nanoassembly structure Modelling

PROJECT MANAgEMENT:RECENT DEVELOPMENTS AND RESEARCH OPPORTUNITIES

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Journal of Systems Science and Systems Engineering 2012年第2期21卷 129-143页

作者： Nicholas g.HALL Department of Management Sciences Fisher College of Business The Ohio State UniversityUSA

This paper studies the business process known as project management. This process has exhibited a remarkable growth in business interest over the last 15 years, as demonstrated by a 1000% increase in membership in the Project Management Institute since 1996. This growth is largely attributable to the emergence of many new diverse business applications that can be successfully managed as projects. The new applications for project management include IT implementations, research and development, new product and service development, corporate change management, and software development. The characteristics of modem projects are typically very different from those of traditional projects such as construction and engineering, which necessitates the development of new project management techniques. We discuss these recent practical developments. The history of project management methodology is reviewed, from CPM and PERT to the influential modem directions of critical chain project management and agile methods. We identify one important application area for future methodological change as new product and service development. A list of specific research topics within project management is discussed. The conclusions suggest the existence of significant research opportunities within project management.

关键词： Project management overview recent practical developments opportunities for research

Two-point Dixon and six-point Dixon magnetic resonance techniques in the detection,quantification and grading of hepatic steatosis

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World Journal of Radiology 2023年第10期15卷 293-303页

作者： Mohamed Elfaal alanna Supersad Craig Ferguson Stephanie Locas Florin Manolea Mitchell P Wilson Medica Sam Wendy Tu gavin Low Department of Radiology&Diagnostic Imaging University of AlbertaEdmonton T6G2B7AlbertaCanada

BACKgROUND Hepatic steatosis is a very common problem *** To assess the performance of two-and six-point Dixon magnetic resonance(MR)techniques in the detection,quantification and grading of hepatic *** A single-center retrospective study was performed in 62 patients with suspected parenchymal liver *** sequences included two-point Dixon,six-point Dixon,MR spectroscopy(MRS)and MR *** fraction(FF)estimates on the Dixon techniques were compared to the MRS-proton density FF(PDFF).Statistical tests used included Pearson’s correlation and receiver operating *** FF estimates on the Dixon techniques showed excellent correlation(≥0.95)with MRS-PDFF,and excellent accuracy[area under the receiver operating characteristic(AUROC)≥0.95]in:(1)Detecting steatosis;and(2)grading severe steatosis,(Pg T2**** estimates on six-point Dixon vs MRS-PDFF showed a moderate correlation(0.82)in iron overload vs an excellent correlation(0.97)without iron overload,(Pgrading mild steatosis improved(AUROC:0.59 to 0.99)when iron overload cases were *** excellent correlation(>0.9)between the Dixon techniques vs MRSPDFF did not change in the presence of liver fibrosis(P<0.01).CONCLUSION Dixon techniques performed satisfactorily for the evaluation of hepatic steatosis but with exceptions.

关键词： Chemical shift encoded Dixon magnetic resonance techniques Hepatic steatosis Liver fat quantification Magnetic resonance spectroscopy Proton density fat fraction Ultrasound

Passive electrochemical hydrogen recombiner for hydrogen safety systems:prospects

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Nuclear Science and Techniques 2023年第6期34卷 215-224页

作者： A.V.Avdeenkov D.g.Bessarabov D.g.Zaryugin All Russian Research Institute for Nuclear Power Plants Operation JSC 25 Ferganskaya Str.MoscowRussia109507 HySA Center Faculty of EngineeringNorth-West UniversityPotchefstroom2520South Africa State Atomic Energy Corporation Rosatom 24 Bolshaya Ordynka Str.MoscowRussia119017

This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operating principle for hydrogen fuel cells to establish forced circulation of the hydrogen mixture as an alternative to natural circulation(as is not utilized in conventional passive autocatalytic hydrogen recombiners currently used in nuclear power plants(NPPs)).The proposed concept of applying the physical operation principles of a PEHR based on a fuel cell simultaneously increases both productivity in terms of recombined hydrogen and the concentration threshold of flameless operation(the‘ignition’limit).Thus,it is possible to reliably ensure the hydrogen explosion safety of NPPs under all conditions,including beyond-design *** experimental setup was assembled to test a laboratory sample of a membrane electrode assembly(MEA)at various hydrogen concentrations near the catalytic surfaces of the electrodes,and the corresponding current–voltage characteristics were *** simplest MEA based on the Advent P1100W PBI membrane demonstrated stable performance(delivery of electrical power)over a wide range of hydrogen concentrations.

关键词： Recombiner Catalytic ignition Hydrogen explosion safety Hydrogen fuel cell Membrane electrode assembly

Increased syndecan-1 and glypican-3 predict poor perinatal outcome and treatment resistance in intrahepatic cholestasis

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Hepatobiliary & Pancreatic Diseases International 2020年第3期19卷 271-276页

作者： Basak gümüs güler Sibel Ozler Department of Health Sciences Istinye UniversityIstanbul 34010Turkey Department of Perinatology Selcuk University Faculty of MedicineKonya 42130Turkey

Background:Intrahepatic cholestasis of pregnancy(ICP)increases the risk of adverse pregnancy *** study aimed to explore the association between serum syndecan-1 and glypican-3 levels and the adverse perinatal outcome as well as the responses to the treatment of ursodeoxycholic acid(UDCA).Methods:This prospective,case control study included 88 pregnant women(44 women with ICP and 44 healthy controls).The primary end points were the perinatal outcome and the response to UDCA therapy.A logistic regression model was used to identify the independent risk factors of adverse pregnancy outcomes and reduced response to UDCA ***:Women with ICP had significantly higher serum syndecan-1(1.27±0.36 ng/m L vs.0.98±0.50 ng/m L;P=0.003),glypican-3(1.78±0.13 ng/m L vs.1.69±0.16 ng/m L;P=0.004),AST(128.59±1.44 vs.13.29±1.32 U/L;Pglypican-3(OR=8.465,95%CI:3.372–21.248;P=0.007),ALT(OR=1.382,95%CI:1.131–1.690;P=0.002),and postprandial bile acid(PBA)(OR=3.392,95%CI:1.003–12.869;P=0.026)were correlated to *** adverse neonatal outcome was related to increased glypican-3(OR=4.275,95%CI:2.726–5.635;P=0.039),and PBA(OR=3.026,95%CI:1.069–13.569;P=0.037).Increases of syndecan-1(OR=7.464,95%CI:2.130–26.153,P=0.017)and glypican-3(OR=6.194,95%CI:2.951–13.002;P=0.025)were the risk factors of decreased response to UDCA ***:Syndecan-1 and glypican-3 might be powerful determinants in predicting adverse perinatal outcome in patients with ICP,and they can be used to predict the response to the UDCA treatment.

关键词： Intrahepatic cholestasis of pregnancy Syndecan-1 glypican-3 Adverse perinatal outcome Response to UDCA

A Review on Friction Stir Welding of Steels

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 195-223页

作者： Dhanesh g Mohan ChuanSong Wu Institute of Materials Joining Shandong UniversityJinan 250016China

Friction Stir Welding(FSW)is the most promising solid-state metals joining method introduced in this *** to the conventional fusion welding methods,this FSW can produce joints with higher mechanical and metallurgi-cal ***,FSW was adopted for low melting metals like aluminum *** recent years it has made significant progress in friction stir welding of steels since unfavourable phase transformations occurred in welds due to the melting of the parent and filler metals in fusion welding can be *** main advantage of FSW over traditional fusion welding is the reduction in the heat-affected zone(HAZ),and the joints exhibit excellent mechanical and corrosion resistance *** article reviews the progress in the relevant issues such as the FSW tool mate-rials and tool profiles for joining steels,microstructure and mechanical properties of steels joints,special problems in joining dissimilar ***,in-situ heating sources was used to overcome the main limitations in FSW of hard metals and their alloys,i.e.,tool damages and insufficient heat *** in-situ heating sources like laser,induction heat,gas tungsten arc welding assisted FSW for various types of steels are introduced in this *** the basis of the up-to-date status,some problems that need further investigation are put forward.

关键词： Friction stir welding Steels Microstructure Mechanical testing Hybrid welding