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Journal of Iron and Steel Research International 2023年第2期30卷 328-337页

作者： Xiao-hong Chu Peng-fei Gao Wei-jian Chen Feng Li Tao Kang Yan zhao Xian-dong Yin Zheng-zhi zhao Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Beijing Laboratory for Modern Transportation Advanced Metal Materials and Processing Technology University of Science and Technology BeijingBeijing100083China Technical Center Shougang Jingtang United Iron and Steel Co.Ltd.Tangshan063200HebeiChina

The effects of Cr contents(0.3 and 1.0 wt.%)and isothermal holding temperatures(400,440,and 480℃)on the microstructure evolution and properties of complex phase steel with high formability(CH steel)were investigated using dilatometry,scanning electron microscopy,transmission electron microscopy(TEM),and X-ray *** results show that the microstructures of CH steel with 0.3 wt.%Cr are ferrite,granular bainite,martensite,and retained austenite,while no ferrite is observed in the microstructure of CH steel with 1.0 wt.%Cr in the same *** promotes the precipitation of(Nb,Ti)C in the high-temperature austenite region through theoretical calculations and TEM *** retards the bainite transformation and refines the grain size of CH ***,as isothermal holding temperature increases from 400 to 480℃,the bainite and retained austenite fractions of two CH steels decrease,while the martensite fraction increases in the steels after final ***,the strength has an increasing tendency and the total elongation has a decreasing tendency with increasing isothermal temperature.

关键词： Complex phase steel High formability steel CH steel Cr Isothermal holding temperature Microstructure Mechanical property

Ni_(3)S_(2) nanocrystals in-situ grown on Ni foam as highly efficient electrocatalysts for alkaline hydrogen evolution

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Rare Metals 2023年第10期42卷 3420-3429页

作者： Rui Sun Zhan-Hua Su zhi-Feng zhao Mei-Qi Yang Tian-Sheng Li Jing-Xiang zhao Yong-Chen Shang College of Chemistry Guangdong University of Petrochemical TechnologyMaoming525000China College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin150025China

The exploitation of cost-efficient electrocatalysts is critical to develop the hydrogen evolution reaction(HER) for hydrogen ***,Ni_(3)S_(2)/NF-x h(x=12,16 and 20,reaction time) nanocrystals in-situ grown on Ni foam(NF) were prepared via a facile hydrothermal *** results demonstrate that the reaction time plays key roles in the morphology,the hydrogen evolution performance of the samples,and the hydrogen brittleness of NF ***,the Ni_(3)S_(2)/NF-16 h displays outstanding catalytic activity for HER in alkaline solution and avoids the hydrogen brittleness of the NF skeletons *** afford a catalytic current of20 mA·cm^(-2),Ni_(3)S_(2)/NF-16 h presents ultra-low overpotential of 48 mV for hydrogen evolution and sufficient stability for 40 ***,the density functional theory(DFT) calculations revealed that the excellent electrocatalytic HER activity of Ni_(3)S_(2) could be attributed to its exposed(015) plane,which exhibited good capability for water adsorption and dissociation in an alkaline electrolyte,leading to the optimal free energy for H^(*) *** present work offers a novel strategy to design,synthesize and develop highly efficient electrocatalysts for HER.

关键词： Ni_(3)S_(2) Electrocatalysts Hydrogen evolution reaction Density functional theory calculations

Effect of Cr on microstructure and oxidation behavior of TiAl-based alloy with high Nb

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China Foundry 2018年第1期15卷 17-22页

作者： Zhu-Hang Jiang Cheng-zhi zhao Jiao-Jiao Yu He-Xin Zhang zhi-Ming Li Key Laboratory of Superlight Materials and Surface Technology College of Materials Science and Chemical Engineering Harbin Engineering University College of Power and Energy Engineering Harbin Engineering University

Three novel multi-microalloying TiAl-based alloys containing high Nb were designed and fabricated Thermogravimetric method was applied to investigate the influence of Cr on the oxidation behavior of high Nb TiAl alloy at 1,073 K for 200 h in laboratory air. The 2 at.% and 4 at.% Cr were added into the alloy,(respectivel named 2 Cr and 4 Cr compared to the Cr-free ternary alloy, 0 Cr alloy). The alloys' microstructure and compositio as well as the composition distribution of the oxidation scale were analyzed by means of Scanning Electro Microscopy(SEM), Energy Dispersive Spectroscopy(EDS), and X-Ray Diffractometry(XRD). The results show that the addition of Cr decreases the grain size of the Nb-TiAl alloy and leads to a transformation from a full lamellar structure to a nearly fully lamellar structure. When oxidized at 1,073 K for 200 h, the oxidized mass gai of the alloy increases with an increase in Cr addition amount in the first 100 h and decreases in the last 100 h With the increase of Cr content, the oxidation surface turns compact but uneven in morphology, which may affec the oxidation resistance of the alloy by increasing the peeling off risk of the oxidation layer at friction conditions.

关键词： TiAl-based alloys microstructure oxidation Cr addition

The prospects of using gravitational waves for constraining the anisotropy of the Universe

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Chinese Physics C 2019年第7期43卷 112-117页

作者： zhi-Chao zhao Hai-Nan Lin Zhe Chang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China

The observation of GW150914 gave a new independent measurement of the luminosity distance of a gravitational wave event. In this paper, we constrain the anisotropy of the Universe by using gravitational wave *** simulate hundreds of events of binary neutron star merger that may be observed by the Einstein Telescope. Full simulation of the production process of gravitational wave data is employed. We find that 200 binary neutron star merging events with the redshift in (0,1) observed by the Einstein Telescope may constrain the anisotropy with an accuracy comparable to that from the Union2.1 supernovae. This result shows that gravitational waves can be a powerful tool for investigating cosmological anisotropy.

关键词： gravitational wave anisotropic space-time gravitational wave detector

Enantioselective synthesis of 2-amino-3-nitrile-chromenes catalyzed by cinchona alkaloids:A remarkable additive effect

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Chinese Chemical Letters 2016年第1期27卷 25-30页

作者： Yuan-Qin Zheng Chun-Feng Luan zhi-Jing Wang Yong-Qi Yao zhi-Chuan Shi Xue-Feng Li zhi-Gang zhao Feng Chen College of Chemistry and Environment Protection Engineering Southwest University for Nationalities Chengdu 610041China

2-Amino-3-nitrile-chromenes with potential antitumor activity were constructed by a novel catalytic system. In combination with a-naphthol, quinine could effectively promote the Michael-cyclization process of malononitrile with functionalized chalcones in high yields and moderate to good enantioselectivity（up to 84% ee）. It is notable that the enantioselectivity could be greatly improved when a-naphthol was employed as additive.

关键词： Additive effect 2-Amino-3-nitrile-chromene Functionalized chalcones Enantioselective

EVALUATION OF ORAL MIDAZOLAM AS CONSCIOUS SEDATION FOR PEDIATRIC PATIENTS IN ORAL RESTORATION

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Chinese Medical Sciences Journal 2006年第3期21卷 163-166页

作者： Kuo Wan Quan Jing Ji-zhi zhao Department of Endodontics Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To evaluate the effect of midazolam alone on sedation in young children for dental restorative care. Methods Forty children, aged 5 to 10 years with a mean age of 7.3 years, participated in this study. Twenty-one patients were assigned to intervention group received 0. 5 mg/kg of oral midazolam 20 minutes prior to the beginning of dental treatment, and 19 patients in control group received placebo liquid 20 minutes before treatment. All patients received painless local anesthetic injection and were restrained with children＇s board and bands. Blood pressure （ BP）, heart rate （HR）, oxygen saturation, treatment compliance scores of the Ramsay scale, the Briekopf and Butmer scale, Frankl scale, and the Houpt scale were recorded. Each procedure was taped and all the data were evaluated every 5 minutes by an anesthetist or experienced dentist who was unaware of the drug given to the child. Results HR in intervention group （82. 5 ± 5.1 bpm） was much lower than that in control group （95.2 ± 8.9 bpm; F=31.20, P 〈0. 001 ）. Intervention group had a significantly lower systolic BP level （94.8±5.6 mmHg） than control group （98.5±5.5 mm Hg; F=4. 34, P =0. 04）, but the diastolic BP （63.0 ± 3.5 mm Hg） was not significantly lower than control group （ 65.5 ± 4. 8 mm Hg; F = 3.31, P = 0. 07 ）. Children in intervention group showed more compliance. The patients＇ scores of the Ramsay scale, Briekopf and Buttner scale, Frankl scale, and Houpt scale in intervention group （ 1.37 ± 0. 96, 1.37 ± 0. 83, 1.32 ± 0. 67, and 2. 32 ± 1.49, respectively） were significantly lower than those in control group （3.71 ± 1.23, 2.71 ± 0. 96, 2.71 ± 0. 90, and 4.71 ± 1.19 ; F = 44. 66, 22. 36, 30.39,and 31.88,respectively,all P〈0.001） Conclusions Oral midazolam alone is safe and produces effective sedation for the dental treatment of young children. Oral midazolam application should be generally preferred because it is more easily accepted by pediatric patients.

关键词： midazolam oral administration dental anxiety dental restoration

Effect of Annealing Process on Microstructure and Mechanical Property of 1100 MPa Grade TRIP Steel

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Journal of Iron and Steel Research International 2015年第7期22卷 622-629页

作者： Hong-xiang YIN Zheng-zhi zhao Ai-min zhao Xiao LI Han-jiang HU Jiang-tao LIANG Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing Laboratory of Metallic Materials and Processing for Modern Transportation

To develop super-high strength TRIP steel for automobile application with good combination of strength and plasticity, an ultra high-strength TRIP steel 0.2 %C-2.0% Si-1.8% Mn was investigated at different intercritical annealing temperatures and bainitic isothermal temperatures. Microstructures were observed by scanning electron mi- croscopy, transmission electron microscopy, electron backscatter diffraction, and X-ray diffraction, and mechanical properties were tested under a uniaxial tensile testing machine. It shows that the best comprehensive mechanical properties were obtained for the experimental steel particularly annealed at 820 ℃ and austempered at 410 ℃. Yield strength of the tested steel mainly depends on ferrite, while the high strength of the tested steel is related to mar- tensite which forms through blocky austenite transformation during cooling and subsequent tensile test attributed to the TRIP effect. Hence, it could be concluded that the grain size of the retained austenite and carbon content in re- tained austenite are the main reasons for high elongation of the tested steel.

关键词： TRIP steel retained austenite intercritical annealing bainitic isothermal temperature automobile steel

The role of CO_(2)dissociation in CO_(2)hydrogenation to ethanol on CoCu/silica catalysts

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Nano Research 2023年第5期16卷 6128-6133页

作者： Zhongyan Wang Chengsheng Yang Xianghong Li Xiwen Song Chunlei Pei zhi-Jian zhao Jinlong Gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyCollaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

CoCu-based catalysts are widely used in CO_(x) hydrogenation reactions to produce higher alcohols due to the C–C coupling ability of Co and the ability of Cu to produce *** work describes the role of easily happened CO_(2)dissociation on the CoCu surface during the reaction,using different silica support to tune the metal–support interaction,reaches different selectivity to *** supported on mesoporous silica MCM-41 shows ethanol selectivity as high as 85.3%,the ethanol space-time yield(STY)is 0.229 mmol/(gmetal∙h),however,poor selectivity to ethanol as low as 28.8%is observed on CoCu supported on amorphous *** different selectivity is due to the different intensities of CO_(2)dissociation on the *** adsorbed O*produced via CO_(2)dissociation can occupy the cobalt hollow sites on CoCu surfaces,which are also the adsorption sites of C1 intermediates for further C–C coupling.

关键词： CO_(2)hydrogenation bimetallic catalysts cobalt catalysts CO_(2)dissociation ethanol synthesis

Ligustrazine inhibits high voltage-gated Ca^(2+) and TTX-resistant Na^+ channels of primary sensory neuron and thermal nociception in the rat:a study on peripheral mechanism

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Neuroscience Bulletin 2006年第2期22卷 79-84页

作者： Bi-Hua BIE Yong CHEN zhi-Qi zhao Institute of Shanghai Physiology Chinese Academy of Sciences Shanghai 200031 China Institute of Neurobiology Fu-Dan University Shanghai 200433 China

Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinociceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency （PWL） to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion （DRG） neurons. Results Intraplantar injection of ligustrazine （0.5 mg in 25 μl） significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion （DRG） neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin （TTX） -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron .in the rat.

关键词： ligustrazine nociception dorsal root ganglion sodium channel calcium channel

Influence of original microstructure on the transformation behavior and mechanical properties of ultra-high-strength TRIP-aided steel

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International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 262-271页

作者： Hong-xiang Yin Ai-min zhao Zheng-zhi zhao Xiao Li Shuang-jiao Li Han-jiang Hu Wei-guang Xia Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences

The transformation behavior and tensile properties of an ultra-high-strength transformation-induced plasticity （TRIP） steel （***） were investigated by different heat treatments for automobile applications. The results show that F-TRIP steel, a tradi- tional TRIP steel containing as-cold-rolled ferfite and pearlite as the original microstructure, consists of equiaxed grains of intercritical ferrite surrounded by discrete particles of M/RA and B. In contrast, M-TRIP steel, a modified TRiP-aided steel with martensite as the original mi- crostlucture, containing full martensite as the original microstructure is comprised of lath-shaped grains of ferrite separated by lath-shaped martensite/retained austenite and bainite. Most of the austenite in F-TRIP steel is granular, while the austenite in M-TRIP steel is lath-shaped. The volume fraction of the retained austenite as well as its carbon content is lower in F-TRIP steel than in M-TRIP steel, and austenite grains in M-TRIP steel are much finer than those in F-TRIP steel. Therefore, M-TRIP steel was concluded to have a higher austenite stability, re- sulting in a lower transformation rate and consequently contributing to a higher elongation compared to F-TRIP steel. Work hardening be- havior is also discussed for both types of steel.

关键词： high strength steels transformation-induced plasticity phase transformations mechanical properties original microstructure work hardening