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Nitric Oxide and Brassinosteroids Mediated Fungal Endophyte-Induced Volatile Oil Production Through Protein Phosphorylation Pathways in Atractylodes lancea Plantlets

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Journal of Integrative Plant Biology 2013年第11期55卷 1136-1146页

作者： cheng-gang Ren Chuan-Chao Dai Jiangsu Key Laboratory for Microbes and Functional Genomics Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources College of Life Sciences in Nanjing Normal University

Fungal endophytes have been isolated from almost every plant, infecting their hosts without causing visible disease symptoms, and yet have still proved to be involved in plant secondary metabolites accumulation. To decipher the possible physiological mechanisms of the endophytic fungus-host interaction, the role of protein phosphorylation and the relationship between endophytic fungus-induced kinase activity and nitric oxide （NO） and brassinolide （BL） in endophyte-enhanced volatile oil accumulation in Atractylodes lancea plantlets were investigated using pharmacological and biochemical approaches. Inoculation with the endophytic fungus Gilmaniella sp. ALl2 enhanced the activities of total protein phosphorylation, Ca2^-dependent protein kinase, and volatile oil accumulation in A. lancea plantlets. The upregulation of protein kinase activity could be blocked by the BL inhibitor brassinazole. Furthermore, pretreatments with the NO-specific scavenger cPTIO significantly reduced the increased activities of protein kinases in A. lancea plantlets inoculated with endophytic fungus. Pretreatments with different protein kinase inhibitors also reduced fungus-induced NO production and volatile oil accumulation, but had barely no effect on the BL level. These data suggest that protein phosphorylation is required for endophyte- induced volatile oil production in A. lancea plantlets, and that crosstalk between protein phosphorylation and the NO pathway may occur and act as a downstream signaling event of the BL pathway.

关键词： Atractylodes lancea endophytic fungus protein phosphorylation signal molecule volatile oi1.

Compound jet generated from an impacted concave dual-layer liquid surface

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Journal of Hydrodynamics 2021年第2期33卷 390-394页

作者： Xiang-gang cheng Xiao-peng Chen School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China

By impacting a concave dual-layer liquid(with the oil and the dyed water)surface in a test tube,a compound jet with a water core and an oil shell is *** velocities of the jet's head(Vj)and the oil-water interface(Vj')are experimentally determined against the initial thickness and the viscosity of the upper layer *** results show that the oil-water interface can be roughly regarded as a pure material surface,whose velocity can be determined from the jet velocity and the initial location(or the film thickness).Furthermore,the effective density,viscosity and surface tension of the compound jet are used to evaluate the jetting *** previous scaling relation for a single liquid jet can be used to give a good prediction with the effective *** results of this paper can be used for the compound jet/droplet preparation.

关键词： Compound jet dual-layer liquid viscosity interface tension

Effects of Pr on the structure and magnetic properties of FePt alloys

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Rare Metals 2007年第1期26卷 19-22页

作者： cheng gang GU Zhengfei ZGOU Huaiying cheng Jun YUAN Songliu Department of Physics Huazhong University of Science and Technology Wuhan 430074 China Department of Information Materials Science and Engineering Guilin University of Electronic Technology Guilin 541004 China

The effects of Pr on the structure and magnetic properties of PrxFe60.5-xPt39.5 alloys （x = 0, 0.5, 1.0, and 1.5） were investigated. X-ray diffraction data indicated that the phase transition temperature of FePt based alloys from disordered face-centered-cubic to ordered face-centered-tetragonal cubic decreases with the increase in Pr concentration. Pr plays the role of a grain refiner and it can enhance the exchange coupling between soft magnetic phase and hard magnetic phase. The results indicate that the replacement of Fe by Pr can significantly improve the remanence and coercivity of the Fe60.5Pt39.5 alloy. These results can be explained on the basis of phase transformation and microstructure. Both the remanence ratio and coercivity of the FePt based alloy as a function of the Pr content are increased by the optimum addition of 0.5 at.% Pr.

关键词： phase transformation exchange coupling anisotropy constant Fe-Pt based alloys

Correlations of Ni Contents, Formation of Reversed Austenite and Toughness for Ni-Containing Cryogenic Steels

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Acta Metallurgica Sinica(English Letters) 2017年第3期30卷 238-249页

作者： Meng Wang Zhen-Yu Liu cheng-gang Li State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 China

It has been widely demonstrated that addition of Ni in low-carbon steels can effectively improve the cryogenic toughness, but the mechanism behind it has yet to be clarified. In the present work, the evolutions of microstructure and mechanical properties after quenching and tempering for Ni-containing cryogenic steels with different Ni contents （3.5-9 wt%） were investigated. The results showed that after quenching and tempering, the Ni-containing cryogenic steels were composed of tempered martensite and reversed austenite. The volume fraction of reversed austenite has increased from 0 up to 6.3% when the Ni content increases from 3.5% to 9%. The Charpy impact tests indicated that the low- temperature toughness was markedly improved with the increase in Ni content, which can be correlated with the increase in reversed austenite amount. The main contribution of reversed austenite to the toughness lies in：（1） the elimination of cementite precipitates improved the plastic deformation capacity of matrix, and （2） the crack propagation is hindered through plastic deformation.

关键词： Ni-containing cryogenic steel Microstructure Reversed austenite Impact toughness Crackpropagation

Spin-Rotation Coupling in Gravitation with Torsion

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Communications in Theoretical Physics 2007年第3X期48卷 473-476页

作者： QIU Shu-Xia SHAO cheng-gang Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

Based on the theory of gravitation with torsion developed by Hammond [Rep. Prog. Phys. 65 （2002） 599], thc interaction between the intrinsic spin of a particle and the mass source is calculated. It is shown that spin can interact with the gravitimagnetic field created by a rotational mass, where the spin-rotation coupling is also discussed. According to the recent torsion pendulum experiment with polarized electrons by Heckel et al. [Phys. Rev. Left. 97 （2006） 021603], we set a new limit on the value of the torsion coupling constant K as K E [0.53, 0.95], which has improved many orders than the constraints from the early spln-spin experiment with K 〈 2 × 10^14.

关键词： torsion spin-rotation torsion coupling constant

Stellar and HI Mass Functions Predicted by a Simple Preheating Galaxy Formation Model

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 590-594页

作者： Zhi-Jian Luo cheng-gang Shu Department of Physics Jiangxi Normal University Nanchang 330022 Joint Center for Astrophysics Shanghai Normal University Shanghai 200234 Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030

According to the new preheating mechanism of galaxy formation suggested by Mo et al., we construct a simple model of formation of disk galaxies within the current paradigm of galaxy formation. It incorporates preheating, gas cooling, bulge formation and star for- mation. The predicted stellar and HI mass functions of galaxies are discussed and compared with the observations. It is found that our model can roughly match both the observed galaxy luminosity function and the observed HI-mass function.

关键词： galaxies: halos - galaxies: formation - galaxies: bulges - galaxies: cooling flows

Effect of Carburization on the Mechanical Properties of Biomedical Grade Titanium Alloys

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Journal of Bionic Engineering 2011年第1期8卷 86-89页

作者： Yong Luo Haibo Jiang gang cheng Hongtao Liu Institute of Tribology and Reliability Engineering School of Material Science and Engineering China University of Mining and Technology Xuzhou 221116 P. R. China Mechanical and Electrical Engineering Institute Xuzhou Normal University Xuzhou 221116 P. R. China

Titanium cermets were successfully synthesized on the surface of biomedical grade titanium alloys by using sequential carburization method. The mechanical properties such as hardness, fracture toughness and plasticity were measured to estimate the potential application of titanium cermets. The results show that after carburization the surface hardness of titanium cermets was 778 HV, with a significant improvement of 128% compared with that of titanium alloys. In addition, the fracture toughness of titanium cermets was 21.5 × 10^6 Pa.m^1/2, much higher than that of other ceramics. Furthermore, the analysis of the loading-unloading curve in the nanoindentation test also indicates that the plasticity of titanium cermet reached 32.1%, a relatively high value which illustrates the combination of the metal and ceramics properties. The results suggest that sequential carburization should be an efficient way to produce titanium cermets with hard surface, high toughness and plasticity.

关键词： titanium alloys hardness surfaces ceramics sequential carburization

Structural bonding-breakage constitutive model for natural unsaturated clayey soils

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Acta Mechanica Sinica 2010年第6期26卷 931-939页

作者： Guo-Qing Cai cheng-gang Zhao Xiao-Ming Qin Department of Geotechnique.School of Civil Engineering and Architecture Beijing Jiaotong University Beijing 100044China Hydro China Zhongnan Engineering Corporation Changsha 410014China

The natural clayey soils are usually structural and unsaturated,which makes their mechanical properties quite different from the remolded saturated soils.A structural constitutive model is proposed to simulate the bonding-breakage *** this model,the unsaturated soil element is divided into a cementation element and a friction element according to the binary medium theory,and the stress-strain coordination for these two elements is obtained. The cementation element is regarded as elastic,whereas the friction element is regarded as elastoplastic which can be described with the Gallipoli＇s *** theoretical formulation is verified with the comparative experiments of isotropic compressions on the saturated and unsaturated structural *** analyses of the effects of damage variables on the model predictions are further carried out,which show that breakage deformation of natural clayey soils increases with the rising amount of initial defects.

关键词： Unsaturated clayey soils Structure Micro-mechanism of bonding-breakage Constitutive model

Analysis of kinematic and singular configurations of an asymmetrical parallel mechanism

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Journal of China University of Mining and Technology 2008年第1期18卷 135-139页

作者： cheng gang GE Shi-rong Institute of Reliability and Rescue Robotics China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The forward kinematics and singularity configuration of an asymmetrical parallel mechanism with three translational degrees of freedom were analyzed. By establishing the position equations of the mechanism and obtaining the forward solutions, a better decoupling of the mechanism was proved. Based on the Jacobi velocity transfer matrix, the possible singularity configurations were studied and the methods avoiding these configurations discussed. Although improving the rigidity, the 4R structures in the mechanism also resulted in new singularity configurations. By analysis of a feasible instance, this kind of parallel mechanism can avoid all singularity configurations. Meanwhile, it was proved that the design of structure parameters and the choice of inputs range are important for rigidity and stability of parallel mechanisms.

关键词： parallel mechanism forward kinematics singular configuration Jacobi matrix