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Water status in winter wheat grown under salt stress

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Journal of Geographical Sciences 2001年第2期11卷 202-208页

作者： M Larry Lopez C~1, WANG Rong~2. MAO Xue-sen~2. Takahashi Hidenori~1 (1. Hokkaido University, Graduate School of Environmental Earth Science, Sapporo, 060-0810 Japan 2. shijiazhuang institute of agricultural modernization, cas,{2., Hokkaido University Graduate School of Environmental Earth Science shijiazhuang institute of {2. modernization CAS

Properties of the soil surface layer, the temporal pattern of the microclimate variables as well as crop condition were combined to analyze the characteristics of the evapotranspiration from winter wheat fields in a saline soil area. In order to accomplish this analysis, evapotranspiration was divided into evaporation from the soil and transpiration from wheat. Moreover, the effect of soil salinity on evapotranspiration was evaluated through the relationship between actual evapotranspiration and potential evapotranspiration (E a /E o ) and the total soil water potential (Φ) was divided into two components: matric potential (Ψ M ) and osmotic potential (Ψ o ). Two sites with different salinity levels were chosen for this study, located in hebei Province, China. Measurements were conducted in April–May 1997 and May 1998. The Bowen ratio method was used to estimate the actual evapotranspiration (E a ), whereas potential evapotranspiration (E o ) was estimated using Penman’s equation. Measurements of soil evaporation (E s ) were obtained with micro-lysimeters, and transpiration was calculated from the difference betweenE a andE s . The results show that transpiration comprised on average almost 80% of total evapotranspiration. Evaporation from the soil differed slightly between years, but this variation was dominated by the leaf area index (LAI), which ranged from 4 to 5 during the study period of 1997 and 1998. Soil electric conductivity (EC), which is directly related to osmotic potential, ranged from 1.9 to 3.5 mS cm?1 in 1997 and was negligible in 1998. Our results indicate that lower osmotic potential decreases the total soil water potential, thus affecting plant transpiration. Hence, it is possible to say that soil salinity actually decreases evapotranspiration from winter wheat fields.

关键词： evapotranspiration potential evapotranspiration soil salinity water potential wheat

RATIONAL DEVELOPMENT AND UTILIZATION OF WATER RESOURCES IN CHINA

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Bulletin of the Chinese Academy of Sciences 1997年第2期11卷 140-143页

作者： Liu Changming(shijiazhuang institute of {2. modernization, the cas, shijiazhuang) (United Research Center for Water Problems, the cas, Beijing)

Ⅰ. TAKING SUSTAINABLE DEVELOPMENT AS THE FINAL GOAL "Our Common Future" was published in 1987 by the UN Committee of World Environment and Development. In 1992. the "Agenda 2." was approved by the Assembly of Global Environment & Development, in which participated leaders of more than 176 countries. The main theme of the two historical events was sustainable development. Consequently, it is necessary for both the rational develonment and the utilization of water resources

关键词： sustainable rational approved historical shortage establishing hasbeen covering shadow planned

SOIL SALINITY CONTROI,REGARDING SUBSURFACE WATER REGULATION IN NORTH CHINA PLAIN

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Journal of Geographical Sciences 1996年第4期6卷 28-37页

作者： Liu Changming(shijiazhuang institute of Aghcultural {2.,United Research Center for Water Problems, cas, Beijing 100101 People’s Rcyublic of China)

The North China Plain (NCP) lying along the eastern coastal area withgeogriaphical coordinates 100°to 12.°and 30° to 40°W, is one of the mostimportan agncultural ngons in China. A problem in soil salmization has beenfound in vast areas along the lower reaches of the Yellow hiver and north of it. After30 years of work on saline soil amelioration, 2.0 million ha has been improved,accounting for over 60 percen of the total ongnal saline soil area. Ths achievetnenthas ban obtained in close relation to water conservancy work. The author analyzessalthezation amelioration by using measures concerning subsuffoce water *** addition to water conservancy measures, thes paper also descnbes acomprehensive way to ameliorate salthezation in northem NCP. Finally, the authorstresses the necessity of combining all measures together into a whole system forsolving salinization problems in northem NCP.

关键词： soil amelioration salinization water regulation North China Plain

Progress in the participation of Ca2.-calmodulin in heat shock signal transduction

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Progress in Natural Science:Materials International 2009年第10期19卷 1201-1208页

作者： Rengang Zhou a,b,Bing Li c,d,Hongtao Liu a,c,Daye Sun c,d,a institute of Genetics and Physiology,Hebei Academy of agricultural Sciences,{2. 050051,China b Hebei Provincial Key Laboratory of Plant Genetic Engineering,{2. 050051,China c Academy of Life Sciences,Hebei Normal University,{2. 050016,China d Hebei Provincial Key Laboratory of Molecular and Cell Biology,{2. 050016,China [a]institute of Genetics and Physiology Hebei Academy of Agricultural Sciences Shijiazhuang 050051 China [b]Hebei Provincial Key Laboratory of Plant Genetic Engineering Shijiazhuang 050051 China [c]Academy of Life Sciences Hebei Normal University Shijiazhuang 050016 China [d]Hebei Provincial Key Laboratory of Molecular and Cell Biology Shijiazhuang 050016 China

A novel heat shock(HS) signal transduction pathway in plants for the participation of Ca2.-calmodulin(CaM) in HS signal trans-duction was *** induces a rapid increase in intracellular free calcium ion levels([Ca2.]i),and the involvement of phospholipase Cinositol 1,4,5-trisphosphate is one of the factors leading to elevation in [Ca2.]i induced by *** also increases the expression of the CaM gene and the accumulation of the CaM *** CaM isoform,AtCaM3,in Arabidopsis is a key member in the HS signal trans-duction ***3 regulates the activity of CaM-binding protein kinase(AtCBK3) or protein phosphatase(AtPP7),promoting the activation of the HS transcription factor,AtHSFA1a,by phosphorylation/dephosphorylation and the expression of heat shock pro-tein genes,then improving heat tolerance in plants.

关键词： Ca2. Calmodulin Protein kinase Heat shock transcription factor Signal transduction

Effect of Water and Sediment Regulation on Lower Yellow River

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Transactions of Tianjin University 2009年第2期15卷 113-120页

作者：徐国宾司春棣 School of Civil Engineering Tianjin University School of Mechanical Engineering Shijiazhuang Railway Institute

According to the results of the water and sediment regulations of the Yellow River in year 2.02.2.07,the effect of erosion and deposition on the lower reaches,the amount and distribution of erosion and deposition in the river mouth area,the adjustment of river regime,the effect of river regulation projects and changes of flowing capacity of the channel are *** is revealed that the water and sediment regulation is efficient to reduce deposition and improve the flowing capacity and the conditions of sediment transport.

关键词： Yellow River water and sediment regulation river control sediment transport

Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science China Earth Sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG Shuxian2. DU Andao2. GAO Yongfeng3 & HUANG Wei4 1. institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China 2. National Center of Geoanalysis, Chinese Academy of Geological Sciences, Beijing 100037, China 3. shijiazhuang College of Economy, shijiazhuang 056000, China 4. Xizang Bureau of Geology and Mineral Resources, Lhasa 850000, China Chinese Acad Geol Sci Inst Mineral Resources Beijing 100037 Peoples R China Chinese Acad Geol Sci Natl Ctr Geoanal Beijing 100037 Peoples R China shijiazhuang Coll Econ Shijiazhuang 056000 Peoples R China Xizang Bur Geol & Mineral Resources Lhasa 850000 Peoples R China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.2.) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.2.) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 2.—2. Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

Performance of the Cement Matrix Composite Material With Rubber Powder

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Journal of Wuhan University of Technology(Materials Science) 2004年第1期19卷 77-80页

作者：宋少民 Beijing institute of Civil Engineering and Architecture

The effect of the deferent rubber content substituted for fine aggregate on the mortar performance was *** effects of the rubber coated with the coating materials on the mortar compressive strength,bending strength and impact work were *** optimum rubber powder content and the suitable coating material were *** the electrical probe test-BEI,SEI and calcium ion distribution,and the slight crack and the interface between the rubber and cement matrix are *** results show that the rubber powder coated with the surface treatment materials A,B and C has the capability of absorbing a large amount of energy under the compressive and flexural load and the slight cracks of R-C were controlled and restrained.

关键词： rubber powder cement matrix composite material toughness coating material

SH-guided waves in layered piezoelectric/piezomagnetic plates

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Progress in Natural Science:Materials International 2009年第7期19卷 811-816页

作者： Guoquan Nie a,b, Zijun An a, Jinxi Liu b a College of Mechanical Engineering, Yanshan University, Qinhuangdao 066004, China b Department of Engineering Mechanics, shijiazhuang Railway institute, shijiazhuang 050043, China [a]College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China [b]Department of Engineering Mechanics Shijiazhuang Railway Institute Shijiazhuang 050043 China

The propagation of shear horizontal (SH) guided waves in a coupled plate consisting of a piezoelectric layer and a piezomagnetic layer is studied. Both the layers are transversely isotropic and perfectly bonded along the interface. The upper and the lower surfaces of the plate are assumed to be mechanically free, electrically open and magnetically closed. Two different cases are considered. One is that the bulk shear wave velocity of piezoelectric material is larger than that of piezomagnetic material. The other is that the bulk shear wave velocity of piezomagnetic material is larger than that of piezoelectric material. The dispersion relation is obtained while the phase velocity is among the bulk shear wave velocity of two different layers. The numerical results show that the phase velocity approaches the smaller bulk shear wave velocity of the material in the system with the increase in the wave number for different modes. The thickness ratio and the properties of the piezoelectric material have great effect on the dispersion behaviors. The results of this paper can offer some fundamental theory to the application of piezoelectric/piezomagnetic composites or structures.

关键词： Piezoelectric material Piezomagnetic material SH-guided wave Dispersion relation

The spectrum for overlarge sets of directed triple systems

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Science China Mathematics 2007年第10期50卷 1369-1381页

作者： Zi-hong TIAN~(1+) Li-jun JI~2.~1 institute of Mathematics,Hebei Normal University,shijiazhuang 050016,China ~2.Department of Mathematics,Suzhou University,Suzhou 2.5006,China 1. institute of Mathematics Hebei Normal University Shijiazhuang 050016 China 2. Department of Mathematics Suzhou University Suzhou 215006 China

A directed triple system of order v, denoted by DTS(v, λ), is a pair (X,B) where X is a v-set and B is a collection of transitive triples on X such that every ordered pair of X belongs to λ triples of B. An overlarge set of disjoint DTS(v, λ), denoted by OLDTS(v, λ), is a collection {(Y\{y}, Ai)}i,such that Y is a (v + 1)-set, each (Y\{y}, Ai) is a DTS(v, λ) and all Ai's form a partition of all transitive triples of Y. In this paper, we shall discuss the existence problem of OLDTS(v, λ) and give the following conclusion: there exists an OLDTS(v, λ) if and only if either λ = 1 and v = 0, 1 (mod 3), or λ = 3 and v≠2.

关键词： overlarge set directed triple system directed candelabra system