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Nitric Oxide Is required for homeostasis of Oxygen and reactive Oxygen Species in Barley roots under Aerobic Conditions

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Molecular Plant 2014年第4期7卷 747-750页

作者： Kapuganti j. Gupta Kim h. hebelstrup Nicholas j. Kruger r. George ratcliffe Department of Plant Sciences University of OxfordSouth Parks RoadOxfordOX1 3RBUK Department of Molecular Biology and Genetics Aarhus UniversityForsogsvej 14200 SlagelseDenmark

Oxygen, the terminal electron acceptor for mitochondrial electron transport, is vital for plants because of its role in the production of ATP by oxidative phosphorylation. While photosynthetic oxygen production contributes to the oxygen supply in leaves, reducing the risk of oxygen limitation of mitochondrial metabolism under most conditions, root tissues often suffer oxygen deprivation during normal development due to the lack of an endogenous supply and isolation from atmospheric oxygen.

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A field study of a roof bolter canopy air curtain(2nd generation)for respirable coal mine dust control

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International journal of Mining Science and Technology 2019年第5期29卷 711-720页

作者： W.r.reed S.Klima M.Shahan G.j.h.ross K.Singh r.Cross T.Grounds CDC NIOSh Pittsburgh Mining Research DivisionPittsburghPA 15236USA Fletcher&Co. HuntingtonWV 25705USA Prairie State Generating Company LLC Lively GroveIL 62257USA

A 2nd generation roof bolter canopy air curtain(CAC)design was tested by National Institute for Occupational Safety and health(NIOSh)at a Midwestern underground coal *** the study,the roof bolter never operated downwind of the continuous *** a combination of personal Data rams(pDr)and gravimetric samplers,the dust control efficiency of the roof bolter CAC was *** evaluation was determined using three methods:(1)comparing roof bolter operator concentrations underneath the CAC to roof bolter concentrations outside the CAC,(2)comparing roof bolter operator concentrations underneath the CAC to the concentrations at the rear of the bolter,and finally,(3)using the gravimetric data directly underneath the CAC to correct roof bolter operator concentrations underneath the CAC and comparing them to the concentrations at the rear of the *** 1 dust control efficiencies ranged from 53.9%to 60.4%.Method 2 efficiencies ranged from 150.5%to 52.2%,and Method 3 efficiencies ranged from 40.7%to 91%.reasons for negative and low dust control efficiencies are provided in this paper and include:incorrect sampling locations,large distance between CAC and operator,and contamination of intake air from line *** dust concentrations encountered during the testing made it difficult to discern whether differences in concentrations were due to the CAC or due to variances inherent in experimental dust ***,the analyses,especially the Method 3 analysis,show that the CAC can be an effective dust control device.

关键词： Coal roof bolter respirable dust Underground mining

STUDIES OF LOW-CONCENTrATION ChrOMATE PASSIVE FILM FOr ZINC-BASED ALLOY COATED STEEL WIrES

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 736-738页

作者： Li, Y. Wang, h.r. Feng, F.L. Wei, X.j. Northeastern Univ Shenyang China

The corrosion resistance of a low concentration chromate passive film for zinc based alloy coated steel wires was assessed by salt spray and electrochemical corrosion tests. XPS and AES analyses showed that the comp... 详细信息

关键词： chromate passive film zinc based alloy coating XPS AES

Development of mathematical model with a genetic algorithm for automatic arc welding process

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Acta Metallurgica Sinica(English Letters) 2010年第3期23卷 230-240页

作者： D.T.Thao I.S.Kim j.W.jeong j.h.Lee j.Y.Shim h.h.Kim Department of Mechanical Engineering Mokpo National University

This paper is to represent new algorithms to predict process parameters on top-bead width in robotic gas metal arc（GMA） welding *** models have been developed：linear, curvilinear and intelligent model based on full factorial design with two *** analysis was employed for optimization of the coefficients of linear and curvilinear models, while genetic algorithm（GA） was utilized to estimate the coefficients of an intelligent *** only the fitting of these models were checked and compared by using a variance test（ANOVA）, but also the prediction on top-bead width using the developed models were carried out based on the additional *** developed models were employed to investigate the characteristic between process parameters and top-bead *** solutions and graphical representation showed that the intelligent model developed can be employed for prediction of bead geometry in GMA welding process.

关键词： Top-bead width Genetic algorithm Multiple regression robotic arc welding GMA welding

heavy metal concentrations in edible bivalves and gastropods available in major markets of the Pearl river Delta

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journal of Environmental Sciences 2001年第2期13卷 210-217页

作者： FANG Zhan-qiang ChEUNG r.Y.h. WONG M.h. Department of Biology South China Normal UniversityGuangzhou 510631China Department of Biology and Chemistry City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong Institute for Natural resources and Waste Management and Department of BiologyHong Kong Bapt ist UniversityKowloon TongHong Kong

Molluscs are able to accumulate heavy metals and impose health hazard to consumers. The main objective of the present study is to investigate the heavy metal concentrations in edible bivalves and gastropods available in major markets of the Pearl river Delta. Fourteen species of edible molluscs were purchased from six markets in hong Kong and Guangdong Province. The fresh of these biota were tested for their cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), chromium (Cr), antimony (Sb) and tin (Sn) concentrations (based on wet weight). The results indicated that amongst the 14 edible molluscs, only Cd, Pb, Ni, Cr, Sb and Sn concentrations in three species (ruditapes philippinarum, Perna viridis and hemifusus tuba) were within the local regulatory limits. Over 60% of bivalve species exceeded maximum permitted levels of Cd (2 mug/g) and Cr (1 mug/g), while over 40% of gastropod species exceeded the maximum levels of Sb (1 mug/g) and Cr (1 mug/g). Most of the samples collected from hong Kong had significantly higher contents of Pb and Sb, but similar levels of Cd, Cu and Zn when compared with samples collected across the border ( p respectively). In general, the molluscs purchased in Guangdong markets had higher metal contents than those purchased from the hong Kong markets. When compared with the Provisional Tolerable Weekly Intake or Maximum Acceptable Daily Load recommended by FAO/WhO Expert Committee on Food Additives, Cd levels of five species (Anadara ferruginea, Pinna pectinata, Chlamys nobilis, Babylonia lutosa and hemifusus terntanus) and Cr levels of seven species ( Anadara ferruginea, Paphia undulata, Pinna pectinata, Babylonia lutosa, hemifusus terntanus, Cymbium melo and Cipangopaludina chinensis) were higher than both the human daily acceptable limits (for Cd and Cr respectively) and the local regulatory levels (for Cd and Cr respectively).

关键词： heavy metals edible molluscs human health Pearl river Delta

Design of logic process based low-power 512-bit EEPrOM for UhF rFID tag chip

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journal of Central South University 2010年第5期17卷 1011-1020页

作者：金丽妍 LEE j h KIM Y h Department of Electronic Engineering Changwon National University

A 512-bit EEPrOM IP was designed by using just logic process based *** limit the voltages of the devices within 5.5 V,EEPrOM core circuits,control gate(CG) and tunnel gate(TG) driving circuits,DC-DC converters:positive pumping voltage(VPP=4.75 V) ,negative pumping voltage(VNN=4.75 V) ,and VNNL(=VNN/2) generation circuit were *** addition,switching powers CG high voltage(CG_hV) ,CG low voltage(CG_LV) ,TG high voltage(TG_hV) ,TG low voltage(TG_LV) ,VNNL_CG and VNNL_TG switching circuit were supplied for the CG and TG driving ***,a sequential pumping scheme and a new ring oscillator with a dual oscillation period were *** reduce a power consumption of EEPrOM in the write mode,the reference voltages VrEF_VPP for VPP and VrEE_VNN for VNN were used by dividing VDD(1.2 V) supply voltage supplied from the analog block in stead of removing the reference voltage generators.A voltage level detector using a capacitive divider as a low-power DC-DC converter design technique was *** result shows that the power dissipation is 0.34μW in the read mode,13.76μW in the program mode,and 13.66μW in the erase mode.

关键词： electrically erasable programmable read-only memory (EEPrOM) logic process DC-DC converter ring oscillator sequential pumping scheme dual oscillation period radio frequency identification (rFID)

s-rEGULAr DIhEDrAL COVErINGS OF ThE COMPLETE GrAPh OF OrDEr 4

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Chinese Annals of Mathematics,Series B 2004年第1期25卷 57-64页

作者： FENGYANQUAN j.h.KWAK DepartmentofMathematics NorthernJiaotongUniversityBeijing100044China CombinatorialandComputationalMathematicsCenter PohangUniversityofScienceandTechnologyPohang790-784Korea.

A graph is s-regular if its automorphism group acts regularly on the set of its s-arcs. An infinite family of cubic 1-regular graphs was constructed in [7] as cyclic coverings of the three-dimensional hypercube, and a classification of all s-regular cyclic coverings of the complete bipartite graph of order 6 was given in [8] for each s ≥ 1, whose fibre-preserving automorphism subgroups act arc-transitively. In this paper, the authors classify all s-regular dihedral coverings of the complete graph of order 4 for each s ≥ 1, whose fibre-preserving automorphism subgroups act arc-transitively. As a result, a new infinite family of cubic 1-regular graphs is constructed.

关键词： s-regular graphs s-arc-transitive graphs regular coverings

STEADY-STATE CrEEP OF UNIDIrECTIONAL C/C COMPOSITE WITh PYrOLYTIC CArBON MATrIX

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Acta Metallurgica Sinica(English Letters) 1998年第6期11卷 412-416页

作者： r.Shi G.X.hu h.j.Li M.K.Kang Shanghai jiaotong Univ Shanghai China

The steady-state creep behavior of unidirectional C/C(1-D-C/C) composite with pyrolytic carbon matrix was investigated at high temperatures up to 2160℃ and under tensile stress from 133.83 to 213.46MPa. Based on the creep experiment of single specimen method, the apparent activation energy and the stress exponent for steadystate creep were determined by the use of a self-made apparatus and an auto-testing system. Value of apparent activation volume is provided and the creep mechanism has also been discussed.

关键词： 1-D-C/C steady-state creep thermal activation

COMPOSITION OPErATOrS ON BErGMAN SPACES

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Chinese Annals of Mathematics,Series B 2003年第4期24卷 433-448页

作者： j.h.CLIFFOrD ZhENGDEChAO DepaxtmentofMathematicsandStatistics UniversityofMichiganatDearbornDearbornMichigan48128USA DepartmentofMathematics VanderbiltUniversityNashvilleTN37240USA.

The authors obtain function theoretic characterizations of the compactness on the standardweighted Bergman spaces of the two operators formed by multiplying a composition operatorwith the adjoint of another compositio... 详细信息

关键词： Bergman spaces Composition operator