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Changes in Phosphorus Fractions, pH, and Phosphatase Activity in Rhizosphere of Two Rice Genotypes

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Pedosphere 2008年第6期18卷 785-794页

作者： LI Yong-Fu LUO An-Cheng WEI Xing-Hua YAO Xu-Guo college of Environmental and Resource science Zhejiang University Hangzhou 310029 （China） School of Environmental science and technology Zhejiang Forestry University Lin＇an 311300 （China） State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 （China）

A rhizobox experiment with two phosphorus (P) treatments, zero-P (0 mg P kg-1) and plus-P (100 mg P kg-1) as Ca(H2PO4)2·H2O, was conducted to study the chemical and biochemical properties in the rhizosphere of two rice genotypes (cv. Zhongbu 51 and Pembe) different in P uptake ability and their relationship with the depletion of soil P fractions. Plant P uptake, pH, phosphatase activity, and soil P fractions in the rhizosphere were measured. Both total dry weight and total P uptake of Pembe were significantly (P co3-Pi, NaHco3-Po, and NaOH-Pi, where Pi stands for inorganic P and Po for organic P, were observed in the rhizosphere of both Zhongbu 51 and Pembe under both P treatments. Pembe showed a greater ability than Zhongbu 51 in depleting resin-Pi, NaHco3-Pi, NaHco3-Po, NaOH-Pi, and NaOH- Po in the rhizosphere. HCl-Pi and residual-P were not depleted in the rhizosphere of both genotypes, regardless of P treatments despite significant acidification in the rhizosphere of Pembe under zero-P treatment. Higher acid phosphatase (AcPME) activity and alkaline phosphatase (AlPME) activity were observed in the rhizosphere of both Zhongbu 51 and Pembe compared to the corresponding controls without plant. AcPME activity was negatively (P correlated to NaHco3-Po concentration in the rhizosphere of both Zhongbu 51 and Pembe, suggesting that AcPME was associated with the mineralization of soil organic P.

关键词： phosphatase phosphorus fractions rhizosphere rice genotypes soil pH

The precipitation and effect of nano nitrides in HSLC steel

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science china(Technological sciences) 2008年第7期51卷 989-998页

作者： FU Jie1, LIU YangChun1,2 & WU HuaJie1,3 1 School of Metallurgical and Ecological Engineering, University of science and technology Beijing, Beijing 100083, china 2 Shougang technology Research Institute, Shougang (Group) corporation, Beijing 100041, china 3 Metallurgical Engineering Research Institute, University of science and technology Beijing, Beijing 100083, china School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing China Shougang technology Research Institute Shougang (Group) Corporation Beijing China Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing China

The existing forms of N and Al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of AlN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into AlN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. Aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043%. The precipitation of AlN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is AlN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure AlN, but have complex compositions.

关键词： thin slab casting and rolling high strength low carbon steel AlN nano nitride precipitation strengthening

Effect of Porphyromonas gingivalis PrtC on cytokine expression in ECV304 endothelial cells and its level in subgingival plaques from patients with chronic periodontitis

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Acta Pharmacologica Sinica 2007年第7期28卷 1015-1023页

作者： Yan-min WU~2,Li-li CHEN~(2,6),Jie YAN~(3,6),Chun-yan ZHUANG~4,Zhi-yuan GU~5~2 Department of Stomatology,the Second Affiliated Hospital,college of Medicine,Zhejiang University,hangzhou 310009,china ~3 Depart-ment of Medical Microbiology and Parasitology,college of Medicine,Zhejiang University,hangzhou 310006,china ~4 Department ofStomatology,the Affiliated Hospital of the School of Medicine,Ningbo University,Ningbo 315020,china ~5 Department of Oral andMaxillofacial Surgery,the Affiliated Hospital of Stomatology,college of Medicine,Zhejiang University,hangzhou 310006,china Department of Stomatology the Second Affiliated Hospital College of Medicine Zhejiang University Hangzhou China Department of Medical Microbiology and Parasitology College of Medicine Zhejiang University Hangzhou China Department of Stomatology the Affiliated Hospital of the School of Medicine Ningbo University Ningbo China Department of Oral and Maxillofacial Surgery the Affiliated Hospital of Stomatology College of Medicine Zhejiang University Hangzi China

Aim:To investigate the effect of the collagenase gene (prtC) product ofPorphyromonas gingivalis on inducing host cells to secrete inflammatorycytokines,and to discuss the correlation between the PrtC level in subgingivalplaque samples and clinical ***:A prokaryotic expression sys-tem pET32a-prtC-Escheria coli BL21 DE3 was *** and im-munoreactivity of the recombinant PrtC protein (rPrtC) was identified by *** was applied to detect interleukin (IL)-1α,IL-8,and TNF-α levelsin supernatants from rPrtC-induced human umbilical vein endothelial cells (HUVEC)originated ECV304 *** parameters recorded at baseline and after treat-ment included bleeding on probing (BOP),probing depth (PD),and attachmentloss (AL).ELISA was established to measure the PrtC level in 196 subgingivalplaque samples from 49 patients with chronic ***:After co-incubation with 1 μg/mL rPrtC for 24 h and with 5 or 10 μg/mL rPrtC for 12 h,thelevels of IL-1α,IL-8,and TNF-α secreted by the ECV304 cells increased signifi-candy (P6 mm PDsites was higher than that in the BOP-negative or the ≤2 mm AL or ≤6 mm PD sites(P6 mm PD sites,the PrtC levels changed insignifi-cantly (P>0.05).conclusion:rPrtC is able to directly induce host cells to synthe-size and secrete IL-1α,IL-8,and TNF-α.The PrtC level in subgingival samples iscorrelated with BOP,AL,and PD.

关键词： Porphyromonas gingivalis collagenase cloning cytokine ELISA

Propagation of liquid surface waves over finite graphene structured arrays of cylinders

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Theoretical & Applied Mechanics Letters 2011年第5期1卷 73-76页

作者： Xuemei Liu,1,2 Yong Wei,1 Sheng Li,1 Yousheng Xu,1,Detang Lu,3 and Boming Yu 4 1) Department of Physics,Zhejiang Normal University,Jinhua 321004,Zhejiang,china 2) hangzhou No.14 Middle School,hangzhou 310006,china 3) Department of Modern Mechanics,University of science and technology of china,Hefei 230027,china 4) School of Physics,Huazhong University of science and technology,Wuahn 430074,china Department of Physics Zhejiang Normal University Jinhua 321004 Zhejiang China hangzhou No. 14 Middle School Hangzhou 310006 China Department of Modern Mechanics University of Science and Technology of China Hefei 230027 China School of Physics Huazhong University of Science and Technology Wuahn 430074 China

Based on the multiple scattering method,this paper investigates a benchmark problem of the propagation of liquid surface waves over finite graphene (or honeycomb) structured arrays of *** the graphene structured array with the square structured and with triangle structured arrays,it finds that the finite graphene structure can produce more complete band gaps than the other finite structures,and the finite graphene structure has less localized ability than the other finite structures.

关键词： propagation liquid surface wave graphene structured array multiple scattering method

Applicability of mass action law to sulphur distribution between slag melts and liquid iron

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Journal of University of science and technology Beijing 2002年第2期9卷 90-98页

作者： Jian Zhang Metallurgy School, University of science and technology Beijing, Beijing 100083, china Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

According to the mass action law and the coexistence theory of slagstructure, the calculating models of mass action concentration for CaO-MgO-FeO-Fe_2O_3-SiO_2,CaO-MgO-MnO-FeO-Fe_2O_3-P_2O_5-SiO_2 and CaO-MgO-MnO-FeO-Fe_2O_3-Al_2O_3-P_2O_5-SiO_2 slag melts areformulated and sulphur distribution between the slag melts and liquid iron is treated. It is foundthat CaO, MnO and FeO promote desulphurization, while MgO is detrimental to desulphurization. Inaddition, the sulphur distribution coefficients between the slag melts and liquid iron andpresented.

关键词： mass action law coexistence theory of slag structure activity massaction concentration

Performance analysis of a noise-normalized FFH/MFSK receiver over Rayleigh fading channels with partial-band noise jamming

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science china(Information sciences) 2011年第1期54卷 129-135页

作者： ZHOU ZhiQiang,LI ShaoQian & CHENG YuFan National Key Laboratory of science and technology on communications,University of Electronic science and technology of china,Chengdu 610054,china National Key Laboratory of science and technology on communications University of Electronic Science and Technology of China Chengdu China

Fast frequency hopping can reduce the degradation caused by *** performance of noise-normalized fast frequency-hopped M-ary orthogonal frequency-shift-keying(FFH/MFSK)receivers over frequency nonselective Rayleigh fading channels with partial-band noise jamming is *** of numerical evaluation,a closed-form error probability expression is given based on the theory of complex variables. The simulation results validate the analytical *** is shown that there is an optimum diversity order and the system performance gets better with an increase in the modulation order.

关键词： anti-jamming fast frequency hopping noise normalization combining Rayleigh fading

The mathematical model of wetting angle of heterogeneous nucleation

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science china(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2 & ZHAO Pei3 1. School of Metallurgical and Ecological Engineering, University of science and technology Beijing, Beijing 100083, china 2. School of Material science, University of science and technology Beijing, Beijing 100083, china 3. Central Iron and Steel Research Institute, Beijing 100081, china School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing China School of Material science University of Science and Technology Beijing Beijing China Central Iron and Steel Research Institute Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2O3 are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

Carbon Solubility and Mass Action concentrations of Fe-Cr-C Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 86-91页

作者： Jtan Zhang(Metallurgy School, University of science and technology Beijing, Beijing 100083, china) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

An empirical equation of carbon solubility in Fe-Cr-C melts is regressed based on the experimental data from references. Acalculating model of mass action concentrations for these melts is formulated on the basis of the coexistence theory of metaIlic melts in-volving compound formation, the phase diagram of Cr-C system as well as thermodynamic data of Fe-Cr-C melts. According to the mod-el, the standard Gibbs free energies of formation of CrC and Cr3C2 are obtained. Satisfactory agreement between the calculated and me-asured values shows that the model can reflect the structural characteristics of Fe-Cr-C melts.

关键词： activity, coexistence theory mass action concentration saturated state

Large-scale information entropy analysis of important sites in mature and precursor miRNA sequences

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science china(Life sciences) 2009年第8期52卷 771-779页

作者： DU JiangFeng1,2,WU YongJun2,ZHANG YinXia3,WU Lei1,2,WANG XiaoLong3,TAO ShiHeng1,2 1 Bioinformatics Center,Northwest science and technology University of Agriculture,Yangling 712100,china 2 college of Life sciences,Northwest science and technology University,Yangling 712100,china 3 college of science,Northwest science and technology University,Yangling 712100,china Bioinformatics Center Northwest Science and Technology University of Agriculture Yangling China college of Life sciences Northwest Science and Technology University Yangling China college of science Northwest Science and Technology University Yangling China

In order to find evidence of consistent sequence conservation or the base correlation degree in miRNA,some important sites in the sequences of reported miRNA and their precursors(pre-miRNA) were investigated via information entropy *** different groups of sites were obtained from special locations(head,tail) in miRNAs of different sources according to taxonomy(animal,plant and virus) and then analyzed by measuring the single base information redundancy(D1(L)) and the adjacent base related information redundancy(D2(L)).The results showed that D2(L) has more information than D1(L),though D1(L) changes roughly consistently with D2(L) in each *** pre-miRNAs are more conservative than those belonging to animals or *** addition,U is dominant in most sites compared with other *** was also found that in the middle of several groups,there were sites where miRNAs were cut down from pre-miRNAs by Enzyme Dicer which were significantly *** phenomenon shows that the conservatism is an aspect of the of miRNA and may be involved in the recognition and cutting by the *** results provided another perspective for understanding more about the primary structure of pre-miRNA.

关键词： miRNA conservative information entropy precursor evolution base correlation degree