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Abrasive Wear Resistance of Dual Phase Steels DP980 and DP600

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Journal of Iron and Steel Research International 2015年第4期22卷 317-323页

作者： Xiu-lin JI Ju-yi WANG Cui-cui JI jian-hua zhao Engineering Research Center of Dredging Technology of Ministry of Education Hohai University College of Mechanical and Electrical Engineering Hohai University

The abrasive wear resistance of dual phase （DP） steels DP980 and DP600 was investigated by using an ASTM rubber wheel abrasion tester. At 2.40 m ·s-1 sliding speed under 19.9 N load with 180--355μm abrasive sands, the wear rates of DP980 and DP600 were 1.01 × 10^-11 and 0.86 ×10^-11 m3 · m-1 , respectively, correspond- ing to about 1.9 and 2.3 times of the relative wear resistance of normal low-carbon steel ASTM A283C. Using di- rectly water quenching from austenitic temperature, the abrasive wear resistance of DP980 samples under 19.9 N load could be improved by 1.65 times. The wear rates of DP980 and DP600 samples decreased respectively with in- creasing sliding speed and abrasive particle size and decreasing applied load. The experimental results reveal that the effect of martensite on the wear resistance not only depends on the volume fraction but also depends on the morphol- ogy, distribution and grain size.

关键词： abrasive wear annealing wear mechanism DP980 steel

Expression of pathogenesis-related genes in cotton roots in response to Verticillium dahliae PAMP molecules

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Science China(Life Sciences) 2017年第8期60卷 852-860页

作者： Xuan Du Sheng Wang Feng Gao Lisha Zhang jian-hua zhao Hui-Shan Guo Chenlei hua State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of Sciences College of Life Sciences University of the Chinese Academy of Sciences College of Agriculture Shihezi University and Key Laboratory at Universities of Xinjiang Uygur Autonomous Region for Oasis Agricultural Pest Management and Plant Protection Resource Utilization

Verticillium wilt disease becomes a major threat to many economically important crops. It is unclear whether and how plant immunity takes place during cotton-Verticillium interaction due to the lack of marker genes. Taking advantage of cotton （Gossypium hirsutum） genome, we discovered pathogenesis-related （PR） gene families, which have been widely used as markers of immune responses in plants. To profile the expression of G. hirsutum PR genes in the process of plant immunity, we treated cotton roots with two immunogenic peptides, fig22 and nlp20 known as pathogen-associated molecular patterns, as well as three Verticillium dahliae-derived peptides, nlp20vd2, nlp23vd3, and nlp23vd4 which are highly identical to nlp20. Quantitative real-time PCR results revealed that 14 G. hirsutum PR gene （GhPR） families were induced or suppressed independently in response to fig22, nip20, nlp20va2, nlp23vd3, and nlp23vd4. Most GhPR genes are expressed highest at 3 h post incubation of immunogenic peptides. Compared to fig22 and nlp20, nlp20vd2 is more effective to trigger up-regulated expression of GhPR genes. Notably, both nlp23vd3 and nlp23vd4 are able to induce GhPR gene up-regulation, although they do not induce necrosis on cotton leaves. Thus, our results provide marker genes and new immunogenic peptides for further investigation of cotton-V, dahliae interaction.

关键词： Verticillium wilt Gossypium hirsutum PR gene PAMP nip20

Experimental and Simulation Studies on Fabricating GCr15/40Cr Bimetallic Compound Rollers Using Electroslag Surfacing with Liquid Metal Method

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Journal of Iron and Steel Research International 2014年第9期21卷 869-877页

作者： Lei RAO Shuang-jun WANG jian-hua zhao Mao-peng GENG Gang DING College of Mechanical and Electronic Engineering Hohai University College of Mechanical and Electronic Engineering Nanchang University Xinya Special Steel Forging Co. Ltd.

Electroslag surfacing with liquid metal （ESSLM） is an excellent method for producing high quality bimetallic compound rollers. The quality of each compound roller is primarily determined by the metallurgical quality of the combined interface. A GCrl5/40Cr compound roller is produced using an ESSLM non-consumable electrode electro- slag heating method. The temperature and electric fields produced by the ESSLM system are calculated. As the roller core moves downward in the mold, it passes through five sections., the preheating section, the rapid heating section, the temperature homogenizing section, the bimetal fusing section and the cooling section which listed from the top to bottom of the mold, respectively. The temperature distribution and the degree of the surface temperature fluctuation in the roller core are different for each section. Near the combined interface, four layers are found from the roller core to the cladding layer= the remelting layer, the fusion layer, the interface solidification layer and the chilling layer, re spectively. Among these, the fusion and interface solidification layers are the key transition zones that greatly influ- ence the combination quality. The surface temperature of the roller core prior to cladding is mainly determined by the drawing velocity, and the thickness of the transition layer increases as the drawing velocity decreases. A transition layer that is too thick or too thin will reduce the mechanical properties at the combined interface. Therefore, the drawing velocity should be limited to a moderate range to produce a satisfactory bimetallic Compound roller.

关键词： bimetallic compound roller ESSLM combined interface drawing velocity numerical simulation

Ultrafast optical probe of coherent acoustic phonons in Co2MnAl Heusler film

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Chinese Physics B 2017年第1期26卷 369-374页

作者： Wei Yan Hai-Long Wang jian-hua zhao Xin-Hui Zhang State Key Laboratory of Supedattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

In this work, pronounced oscillations in the time-resolved reflectivity of Heusler alloy Co2MnAl films which are epitaxially grown on Ga As substrates are observed and investigated as a function of film thickness, probe wavelength,external magnetic field and temperature. Our results suggest that the oscillation response at 24.5 GHz results from the coherent phonon generation in Co2MnAl film and can be explained by a propagating strain pulse model. From the probe wavelength dependent oscillation frequency, a sound velocity of（3.85±0.1）×10-3m/s at 800 nm for the epitaxial Co2MnAl film is determined at room temperature. The detected coherent acoustic phonon generation in Co2MnAl reported in this work provides a valuable reference for exploring the high-speed magnetization manipulation via magnetoelastic coupling for future spintronic devices based on Heusler alloy films.

关键词： Heusler alloys coherent acoustic phonon time-resolved spectroscopy

Origin of carbonate minerals and impacts on reservoir quality of the Wufeng and Longmaxi Shale, Sichuan Basin

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Petroleum Science 2023年第6期20卷 3311-3336页

作者： Yang Chen jian-hua zhao Qin-Hong Hu Ke-Yu Liu Wei Wu c Chao Luo Sheng-Hui zhao Yu-Ying Zhang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong266580China School of Geosciences China University of Petroleum(East China)QingdaoShandong266580China Shale Gas Research Institute PetroChina Southwest Oil and Gas Field CompanyChengduSichuan610051China Northeastern University School of Resources and Civil EngineeringShenyangLiaoning110000China

The Ordovician-Silurian Wufeng and Longmaxi Shale in the Sichuan Basin were studied to understand the genesis and diagenetic evolution of carbonate minerals and their effects on reservoir quality. The results of geochemical and petrological analyses show that calcite grains have a negative Ce anomaly indicating they formed in the oxidizing environment of seawater. The high carbonate mineral contents in the margin of basin indicate that calcite grains and cores of dolomite grains appear largely to be of detrital origin. The rhombic rims of dolomite grains and dolomite concretions with the δ^(13)C of –15.46‰ and the enrichment of middle rare earth elements were formed during the sulfate-driven anaerobic oxidation of methane. The calcite in radiolarian were related to the microbial sulfate reduction for the abundant anhedral pyrites and δ^(13)C value of –11.34‰. Calcite veins precipitated in the deep burial stage with homogenization temperature of the inclusions ranging from 146.70 ℃ to 182.90 ℃. The pores in shale are mainly organic matter pores with pore size mainly in the range of 1–20 nm in diameter. Carbonate minerals influence the development of pores through offering storage space for organic matter. When calcite contents ranging from 10% to 20%, calcite grains and cement as rigid framework can preserve primary pores. Subsequently, the thermal cracking of liquid petroleum in primary pores will form organic matter pores. The radiolarian were mostly partially filled with calcite, which combining with microcrystalline quartz preserved a high storage capacity.

关键词： Carbonate minerals genesis Diagenetic evolution Carbonate mineral types Reservoir quality Wufeng and Longmaxi Shale

Thermal Behavior,Nonisothermal Decomposition Reaction Kinetics of Mixed Ester Double-base Gun Propellants

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Chemical Research in Chinese Universities 2008年第5期24卷 608-614页

作者： YI jian-hua zhao Feng-qi XU Si-yu GAO Hong-xu HU Rong-zu Xi＇an Modern Chemistry Research Institute Xi＇an 710065 P. R. China

The thermal decomposition behavior and nonisothermal reaction kinetics of the double-base gun propellants containing the mixed ester of triethyleneglycol dinitrate（TEGDN） and nitroglycerin（NG） were investigated by thermogravimetry（TG） and differential thermogravimetry（DTG）, and differential scanning calorimetry（DSC） under the high-pressure dynamic ambience. The results show that the thermal decomposition processes of the mixed nitric ester gun propellants have two mass-loss stages. Nitric ester evaporates and decomposes in the first stage, and nitrocellulose and centralite II（C2） decompose in the second stage. The mass loss, the DTG peak points, and the terminated temperatures of the two stages are changeable with the difference of the mass ratio of TEGDN to NG. There is only one obvious exothermic peak in the DSC curves under the different pressures. With the increase in the furnace pressure, the peak temperature decreases, and the decomposition heat increases. With the increase in the content of TEGDN, the decomposition heat decreases at 0.1 MPa and rises at high pressure. The variety of mass ratio of TEGDN to NG makes few effect on the exothermic peak temperatures in the DSC curves at different pressures. The kinetic equation of the main exothermal decomposition reaction of the gun propellant TG0601 was determined as： dα/dt=1021.59（1-α）3e-2.60×104/T. The reaction mechanism of the process can be classified as chemical reaction. The critical temperatures of the thermal explosion（Tbe and Tbp） obtained from the onset temperature（Te） and the peak temperature（Tp） are 456.46 and 473.40 K, respectively. ΔS≠, ΔH≠, and ΔG≠ of the decomposition reaction are 163.57 J·mol^-1·K^-1, 209.54 kJ·mol^-1, and 133.55 kJ·mol^-1, respectively.

关键词： Mixed nitric ester gun propellant Triethyleneglycol dinitrate Thermal behaviors Nonisothermal decomposition reaction kinetics

Magnetic characterization of a thin Co2MnSi/L10–MnGa synthetic antiferromagnetic bilayer prepared by MBE

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Chinese Physics B 2020年第10期29卷 479-483页

作者： Shan Li Jun Lu Si-Wei Mao Da-Hai Wei jian-hua zhao State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences(CAS)Beijing 100083China Center of Materials Science and Optoelectronics Engineering&CAS Center of Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Beijing Academy of Quantum Information Science Beijing 100193China

A synthetic antiferromagnet based on a thin antiferromagnetically coupled Co2MnSi/MnGa bilayer with Pt capping is proposed in this work. Square magnetic loops measured by anomalous Hall effect reveal that a well perpendicular magnetic anisotropy is obtained in this structure. A very large coercivity of 83 kOe (1 Oe = 79.5775 A⋅m^−1) is observed near the magnetic moment compensation point of 270 K, indicating an antiferromagnetic behavior. Moreover, the anomalous Hall signal does not go to zero even at the magnetic compensation point, for which the difficulty in detecting the conventional antiferromagnets can be overcome. By changing the temperature, the polarity of the spin–orbit torque induced switching is changed around the bilayer compensation point. This kind of thin bilayer has potential applications in spin–orbit-related effects, spintronic devices, and racetrack memories.

关键词： exchange coupling magnetization compensation anomalous Hall effect molecular-beam epitaxy

DNA methylation-dependent epigenetic regulationof Verticillium dahliae virulence in p

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aBIOTECH 2023年第3期4卷 185-201页

作者： Yun-Ya Chen Chen Zhu jian-hua zhao Ting Liu Feng Gao Ying-Chao Zhang Cheng-Guo Duan Shanghai Center for Plant Stress Biology and Center of Excellence in Molecular Plant Sciences Chinese Academy of ScienceShanghai 200032China University of Chinese Academy of Sciences Beijing 100049China College of Life Sciences Anhui Normal UniversityWuhu 241000China State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Qilu Zhongke Academy of Modern Microbiology Technology Jinan 250000China

As a conserved epigenetic mark, DNA cytosine methylation, at the 5’ position (5-mC), plays importantroles in multiple biological processes, including plant immunity. However, the involvement of DNAmethylation in the determinants of virulence of phytopathogenic fungi remains elusive. In this study,we profiled the DNA methylation patterns of the phytopathogenic fungus Verticillium dahliae, one of themajor causal pathogens of Verticillium wilt disease that causes great losses in many crops, and exploredits contribution in fungal pathogenicity. We reveal that DNA methylation modification is present in *** and is required for its full virulence in host plants. The major enzymes responsible for theestablishment of DNA methylation in V. dahliae were identified. We provided evidence that DNAmethyltransferase-mediated establishment of DNA methylation pattern positively regulates fungalvirulence, mainly through repressing a conserved protein kinase VdRim15-mediated Ca2? signaling andROS production, which is essential for the penetration activity of V. dahliae. In addition, we furtherdemonstrated that histone H3 lysine 9 trimethylation (H3K9me3), another heterochromatin markerthat is closely associated with 5-mC in eukaryotes, also participates in the regulation of V. dahliaepathogenicity, through a similar mechanism. More importantly, DNA methyltransferase genes VdRid,VdDnmt5, as well as H3K9me3 methyltransferase genes, were greatly induced during the early infection phase, implying that a dynamic regulation of 5-mC and H3K9me3 homeostasis is required for anefficient infection. Collectively, our findings uncover an epigenetic mechanism in the regulation ofphytopathogenic fungal virulence.

关键词： DNA methylation Verticillium dahliae Pathogenicity H3K9me3

Intensity of stromal changes is associated with tumor relapse in clinically advanced prostate cancer after castration therapy

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Asian Journal of Andrology 2014年第5期16卷 710-714,I0007,I0008页

作者： jian-Ping Wu Wen-Bin huang Hui Zhou Lu-Wei Xu jian-hua zhao Jia-Gen Zhu jiang-Hao Su Hong-Bin Sun Department of Urology Nanjing Hospital Affiliated to Nanjing Medical University Nanjing China Department of Pathology Nanjing Hospital Affiliated to Nanjing Medical University Nanjing China

Reactive stromal changes in prostate cancer （PCa） are likely involved in the emergence of castration-resistant PCa （CRPC）. This study was designed to investigate stromal changes in patients with clinically advanced PCa and analyze their prognostic significance. Prostate needle biopsies obtained from 148 patients before castration therapy were analyzed by Masson trichrome staining and immunohistochemical analysis of vimentin and desmin. Reactive stroma grading was inversely correlated with Gleason score. Stroma grade （Masson stain 82.8% vs 45.6%, P 〈 0.001） and vimentin expression （P = 0.005） were significantly higher, and desmin expression （P = 0.004） significantly lower, in reactive stroma of tumors with a Gleason score of 6-7 than in adjacent peritumoral tissue. Kaplan-Meier analysis showed a significant association between reactive stroma grade in tumors and the occurrence of CRPC in patients with a Gleason score of 6-7 （P= 0.009）. Furthermore, patients with higher vimentin or lower desmin expression had a shorter disease-free period. In multivariate analysis, only vimentin expression was a significant predictor of tumor relapse （hazard ratio 1.78, 95% confidence interval 1.12-10.26, P = 0.012）. These findings indicate that the intensity of reactive stroma is associated with castration responsiveness, especially in patients with a lower Gleason score where the abundant stroma component is most frequently found. High expression of vimentin in tumor stroma was independently associated with poor outcomes in patients with Gleason scores of 6-7, and may serve as a new prognostic marker in daily practice.

关键词： cancer-associated fibroblasts castration resistance prostate cancer reactive stroma vimentin