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Surface microstructure control of microalloyed steel during slab casting

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Journal of Iron and Steel Research International 2017年第8期24卷 803-810页

作者： Li-jun Xu Shu-lan Zhang Chun-gen Qiu Sheng-tao Qiu xing-zhong Zhang Central Iron and Steel Research Institute Beijing 100081China

Lots of work has been done to investigate slab surface microstructure evolution during continuous casting in order to improve hot ductility and avoid transverse *** slab surface microstructure after continuous casting was characterized by optical microscopy,and the precipitation behavior was investigated by transmission electron *** the same time,the mechanical properties of the slabs were measured using a Gleeble 1500 Dthermal simulator and the transformation temperatures were examined by means of a thermal *** experimental results show that homogeneous microstructure without film-like ferrites and chain-like precipitates at grain boundary can be obtained through surface intensive cooling and transverse cracks do not occur on the slab *** the experimental steel,fine ferrite can form at slab surface when the water flow rate is larger than 1560L/min at vertical *** the distance to surface increases,microstructure turned to ferrite and ***,nano-size carbonitrides precipitated in the ferrite grain and the size was larger at the junction of the *** mechanical experiment results show that the hot ductility of the sample deformed at 650°C was better than that of the sample deformed at 750°*** reason is that filmlike ferrite formed at the grain boundary in the sample deformed at 750°***,the slab must be cooled quickly below Ar3 to prevent the occurrence of film-like ferrite and transverse cracks on the slab surface during casting.

关键词： Microalloyed steel Surface intensive cooling Ferrite Carbonitride Crack

珠子参总皂苷对人宫颈癌细胞系HeLa增殖、凋亡及自噬的影响

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中国中药杂志 2024年第14期49卷 3848-3856页

作者：庞夏云周瑞宋若彤李楠王雨琪宋忠兴刘妍如唐志书陕西中医药大学/陕西中药资源产业化省部共建协同创新中心/陕西省创新药物研究中心陕西咸阳712046 清华大学化学系生命有机磷化学及化学生物学教育部重点实验室北京100084 中国中医科学院北京100700

探究珠子参总皂苷对人宫颈癌细胞系HeLa增殖、凋亡和自噬的影响。利用紫外-可见分光光度计检测珠子参总皂苷中皂苷的含量;分别运用CCK-8、DAPI染色法及流式细胞术检测珠子参总皂苷对HeLa细胞活力、细胞核形态变化、细胞周期与凋亡的影响... 详细信息

探究珠子参总皂苷对人宫颈癌细胞系HeLa增殖、凋亡和自噬的影响。利用紫外-可见分光光度计检测珠子参总皂苷中皂苷的含量;分别运用CCK-8、DAPI染色法及流式细胞术检测珠子参总皂苷对HeLa细胞活力、细胞核形态变化、细胞周期与凋亡的影响;Western blot技术检测HeLa细胞中凋亡蛋白B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)、活化的半胱氨酸蛋白酶蛋白-9(cleaved caspase-9)、活化的半胱氨酸蛋白酶蛋白-3(cleaved caspase-3),自噬相关蛋白苄氯素1(Beclin-1)和SQSTM1(p62),磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)/哺乳动物雷帕霉素靶蛋白(mTOR)和丝裂原活化蛋白激酶(MAPK)信号通路相关蛋白表达的影响。研究发现,珠子参总皂苷的得出率、皂苷质量分数分别为6.3%、78.3%;珠子参总皂苷可显著抑制HeLa细胞的增殖(P<0.001),影响HeLa细胞核形态,阻滞HeLa细胞G_(0)/G_(1)期周期,诱导细胞凋亡,且呈现一定的浓度依赖性。进一步发现珠子参总皂苷可上调促凋亡蛋白Bax、cleaved caspase-9和cleaved caspase-3和自噬相关蛋白p62的表达(P<0.05),下调抗凋亡蛋白Bcl-2和自噬相关蛋白Beclin-1的表达(P<0.01),促进p-p38丝裂原活化蛋白激酶(p38 MAPK,简称p38)/p38、p-c-Jun氨基末端激酶(JNK)/JNK、p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR水平(P<0.05),对p-ERK/ERK影响不显著。结果表明,珠子参总皂苷可能通过激活PI3K/Akt/mTOR、JNK和p38信号通路,抑制HeLa细胞自噬,促进其细胞凋亡,表明了珠子参可能具有抗宫颈癌的潜在作用。

关键词：珠子参总皂苷 HeLa细胞增殖自噬凋亡

Building highly active hybrid double-atom sites in C_(2)N for enhanced electrocatalytic hydrogen peroxide synthesis

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Green Energy & Environment 2021年第6期6卷 846-857页

作者： Yongyong Cao JinYan Zhao xing zhong Guilin Zhuang Shengwei Deng zhongzhe Wei Zihao Yao Jianguo Wang College of Biological Chemical Science and Engineering Jiaxing UniversityJiaxing314001China Institute of Industrial Catalysis College of Chemical EngineeringState Key Laboratory Breeding Base of Green–Chemical Synthesis TechnologyZhejiang University of TechnologyHangzhou310032China

Two-electron(2 e^(-))oxygen reduction reaction(ORR)shows great promise for on-site electrochemical synthesis of hydrogen peroxide(H_(2)O_(2)).However,it is still a great challenge to design efficient electrocatalysts for H_(2)O_(2)*** address this issue,the logical design of the active site by controlling the geometric and electronic structures is urgently ***,using density functional theory(DFT)computations,two kinds of hybrid double-atom supported on C_(2)N nanosheet(RuCu@C_(2)N and PdCu@C_(2)N)are screened out and their H_(2)O_(2)performances are ***@C_(2)N exhibits higher activity for H_(2)O_(2)synthesis with a lower overpotential of 0.12 V than RuCu@C_(2)N(0.59 V),Ru_(3)Cu(110)facet(0.60 V),and PdCu(110)facet(0.54 V).In aqueous phase,the adsorbed O_(2)is further stabilized with bulk H_(2)0 and the thermodynamic rate-determining step of 2 e^(-) ORR *** activation barrier on PdCu@C_(2)N is 0.43 eV lower than the one on RuCu@C_(2)N with 0.68 ***@C_(2)N is near the top of 2 e^(-) ORR volcano plot,and exhibits high selectivity of H_(2)O_(2.)This work provides guidelines for designing highly effective hybrid double-atom electrocatalysts(HDACs)for H_(2)O_(2)synthesis.

关键词： Hydrogen peroxide(H_(2)O_(2)) Oxygen reduction reaction(ORR) Hybrid double-atoms catalysts(HDACs) Density functional theory(DFT) Aqueous phase

The First Generation of New China Leaders' Thought of Developing Integrated Chinese and Western Medicine

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Chinese Journal of Integrative Medicine 2018年第5期24卷 385-389页

作者： WENG Pan-feng1 LI En-chang1 ZHUANG xing-zhong2 Health and Life Ethics Center Wenzhou Medical University Department of Organizational Work Wenzhou Medical University

The history of integrated Chinese medicine （CM） and Western medicine （WM） witnesses the development of public health under the significant support and guidance of the first generation leaders of new China who aimed at maximizing people＇s health interests. According to the available documents, it can be found out that, among the first generation of new China leaders, MAO Ze-dong, ZHOU En-lai, LIU Shao-qi, ZHU De and DENG Xiao-ping made more statements on the integration of CM and WM due to different division of labor and other historical reasons. This paper will focus on the issue to study the emergence, formation and development of their thoughts on the integration of CM and WM and analyze its process and significance, so as to enlighten the current integration of CM and WM, and even the world＇s integrative medicine.

关键词： In De Thought of Developing Integrated Chinese and Western Medicine The First Generation of New China Leaders WM

Melting Temperature of Individual Electrospun Poly(vinylidene fluoride) Fibers Studied by AFM-based Local Thermal Analysis

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Chinese Journal of Polymer Science 2021年第2期39卷 219-227,I0007页

作者： Ze-Qian Wang Zhen-xing zhong Yu-Ying Ma Xiao-Feng Lu Ce Wang Zhao-Hui Su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China Alan G.MacDiarmid Institute Jilin UniversityChangchun 130012China

Thermal properties such as melting temperature can well reflect the microstructure of the polymer material, and have practical implications in the application of nanofibers. In this work, we investigated the melting temperature of individual electrospun poly(vinylidene fluoride)(PVDF) nanofibers with diameters ranging from smaller than 200 nm to greater than 2 μm by the local thermal analysis technique. The PVDF fibers obtained under four different conditions were found to crystallize into α and β phases, and the fiber mats showed typical values in the crystallinity and Tm with no significant difference among the four. However, analyses at single fiber level revealed broad distribution in diameter and Tm for the fibers produced under identical electrospinning condition. The Tm of individual nanofibers was found to remain constant at large diameters and increase quickly when reducing the fiber diameter toward the nanoscale, and Tm values of 220-230 ℃ were observed for the thinnest nanofibers, much higher than the typical values reported for bulk PVDF. The Tm and molecular orientation at different positions along a beaded fiber were analyzed, showing a similar distribution pattern with a minimum at the bead center and higher values when moving toward both directions. The results indicate that molecular orientation is the driving mechanism for the observed correlation between the Tm and the diameter of the nanofibers.

关键词： Electrospun fibers PVDF Local thermal analysis Melting temperature

高活性方形氧化铅与可视化电解槽协同促进电催化臭氧生产

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Chinese Journal of Catalysis 2024年第2期57卷 80-95页

作者：刘佳王式彬蔡锦福武立振刘云贺佳辉许在祥彭小革钟兴安亮王建国浙江工业大学化工学院工业催化研究所绿色化学合成技术国家重点实验室培育基地浙江杭州310032 香港理工大学机械工程系中国香港九龙

臭氧是一种环境友好型氧化剂,可直接用于消毒、杀菌和废水处理,对于维护和促进公共卫生安全至关重要.由于臭氧容易分解,不利于储存,因此需要现制即用.目前臭氧生成技术主要包括:电晕放电法和电催化臭氧生产(EOP)技术.相较于电晕放电法,... 详细信息

臭氧是一种环境友好型氧化剂,可直接用于消毒、杀菌和废水处理,对于维护和促进公共卫生安全至关重要.由于臭氧容易分解,不利于储存,因此需要现制即用.目前臭氧生成技术主要包括:电晕放电法和电催化臭氧生产(EOP)技术.相较于电晕放电法,EOP是一种本质安全的臭氧生产技术.然而,该工艺相较于电晕放电技术电能消耗量大,为了使其更具商业可行性,有必要开发高活性且低成本的电催化剂.此外,合理的电解槽设计对于实现高效EOP过程也至关重要.然而,目前研究主要集中在提高EOP催化剂活性方面,对电解槽的结构设计优化的关注较少.本文通过开发高效电催化剂进而将其应用于结构优化后的电解槽中,实现了更加高效的EOP过程.本文采用水热方法成功制备了一种具有较高EOP活性的方形氧化铅(PbO_(x)-CTAB-120)电催化剂.在标准三电极测试系统中,电流密度为50 mA cm^(-2)的测试条件下,法拉第效率(FE)可达20.7%,与商用β-PbO_(2)(17.1%)相比提高了21.1%.此外,设计了具有平行流场的可视化EOP电解槽,该可视化电解槽在传质和传热方面具有明显优势,有利于实现更加高效的EOP过程.将催化剂PbO_(x)-CTAB-120组装至可视化电解槽中,在1.0 A cm^(-2)的测试电流密度下,电解液为超纯水,该体系气态臭氧产量可以达到588 mg h^(-1)g^(-1)catalyst,比能量消耗(PEOP)为56 Wh g^(-1)gaseous ozone.体系臭氧产量约为商用β-PbO_(2)在传统电解槽中产量的2倍,并且PEOP降低率超过62%.原位18O同位素标记差分电化学质谱和密度泛函理论计算结果表明,PbO_(x)-CTAB-120电催化剂在EOP过程中遵循晶格氧机理路径,晶格氧迁移产生的氧空位能有效稳定OOH^(*)和O_(2)^(*)反应中间体,因此有利于催化剂在EOP过程中保持较好的反应活性和稳定性.同时,还利用先进的高速摄像可视化工具和计算流体力学(CFD)仿真模拟研究了平行流场EOP电解槽的运行过程和高效传质传热的原理.CFD模拟结果表明,与传统流场模型相比,平行流场对应的出口气泡停留时间更长,说明平行流场更有利于产物气泡从出口逸出,即气泡容易快速扩散,与实验结果一致.因此,PbO_(x)-CTAB-120电催化剂与新型可视化电解槽相结合,有助于在超纯水中实现较好的气态臭氧产率和较低比能耗.此外,二者的结合充分发挥了电催化剂的EOP活性和电解槽的传质特性所带来的优势,实现了反应性和传输性的协同增强,从而极大促进了原位有机污染物降解效率.综上所述,本文在制备高效阳极催化剂的基础上,同时利用优化电解槽结构实现了提升臭氧产率和降低过程能耗,为高活性电催化剂与优化的电解槽耦合以实现高效EOP过程及其有效应用提供参考.

关键词： PbOx-CTAB-120 可视化电解槽电催化臭氧生产计算流体力学模拟原位降解

Three-dimensional graphene membrane cathode for high energy density rechargeable lithium-air batteries in ambient conditions

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Nano Research 2017年第2期10卷 472-482页

作者： xing zhong Benjamin Papandrea Yuxi Xu Zhaoyang Lin Hua Zhang Yuan Liu Yu Huang Xiangfeng Duan Department of Chemistry and Biochemistry University of California Los Angeles Los Angeles CA 90095 USA California Nanosystems Institute University of California Los Angeles Los Angeles CA 90095 USA Department of Materials Science and Engineering University of California Los Angeles Los Angeles CA 90095 USA

Lithium-air batteries have attracted significant interest for applications in high energy density mobile power supplies, yet there are considerable challenges to the development of rechargeable Li-air batteries with stable cycling performance under ambient conditions. Here we report a three-dimensional （3D） hydrophobic graphene membrane as a moisture-resistive cathode for high performance Li-air batteries. The 3D graphene membrane features a highly interconnected graphene network for efficient charge transport, a highly porous structure for efficient diffusion of oxygen and electrolyte ions, a large specific surface area for high capacity storage of the insulating discharge product, and a network of highly tortuous hydrophobic channels for O2/H20 selectivity. These channels facilitate 02 ingression while retarding moisture diffusion and ensure excellent charge/ discharge cycling stability under ambient conditions. The membrane can thus enable robust Li-air batteries with exceptional performance, including a maximum cathode capacity that exceeds 5,700 mAh/g and excellent recharge cycling behavior （〉2,000 cycles at 140 mAh/g, and 〉100 cycles at 1,400 mAh/g）. The graphene membrane air cathode can deliver a lifetime capacity of 100,000-300,000 mAh/g, comparable to that of a typical lithium ion battery cathode. The stable operation of Li-air batteries with significantly improved single charge capacities and lifetime capacities comparable to those of Li-ion batteries may offer an attractive high energy density storage alternative for future mobile power supplies. These batteries may provide much longer battery lives and greatly reduced recharge frequency.

关键词： energy storage graphene framework three-dimensional(3D)-network lithium air-battery water resistive

High-Repetition-Rate and High-Beam-Quality Laser Pulses with 1.5 MW Peak Power Generation from a Two-Stage Nd:YVO4 Amplifier

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Chinese Physics Letters 2019年第11期36卷 22-26页

作者： Qiu-Run He Jing Guo Bao-Fu Zhang zhong-xing Jiao School of Physics Sun Yat-sen UniversityGuangzhou 510275 Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082 National Demonstration Center for Experimental Physics Education Sun Yat-sen UniversityGuangzhou 510275

We develop a two-stage end-pumped Nd:YVO4 amplifier seeded by a passively Q-switched microchip laser. An average output power of 13.5 W with repetition rate up to 7 kHz and pulse duration of ~1.24 ns is obtained,corresponding to a pump extraction efficiency of 16.1%(19.5% for the second stage) and peak power of ~1.5 *** beam quality factors at maximum output power are measured to be Mx2= 1.56 and My2= 1.48. We introduce an analytical model to estimate gain and beam quality after amplification. This model focuses on the influence of ratio of seed spot radius to pump spot radius when designing an amplifier. Moreover, our experiments reveal that the re-imaging system in the double-pass configuration can be used to enhance the beam quality.

关键词： Nd:YVO4 amplifier pump

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秦药产业发展模式及高质量发展路径思考

中国现代中药 2024年第6期26卷 972-977页

作者：唐志书宋忠兴段金廒黄璐琦陕西中医药大学陕西中药资源产业化省部共建协同创新中心/秦药特色资源研究开发国家重点实验室(培育)/陕西省创新药物研究中心/国家中药材产业技术体系咸阳综合试验站陕西咸阳712046 北京中医药大学中药学院北京102488 南京中医药大学江苏省中药资源产业化过程协同创新中心江苏南京210023 中国中医科学院北京100700

秦药产业是根植于三秦大地的中药产业,具有深厚而独特的文化内涵,复兴秦药文化、振兴秦药产业已成为区域产业发展的战略任务之一。因此“聚焦秦药品牌,培育全产业链”的发展模式是实现秦药产业全面转型升级的有效路径与战略举措。按照... 详细信息

秦药产业是根植于三秦大地的中药产业,具有深厚而独特的文化内涵,复兴秦药文化、振兴秦药产业已成为区域产业发展的战略任务之一。因此“聚焦秦药品牌,培育全产业链”的发展模式是实现秦药产业全面转型升级的有效路径与战略举措。按照“育企业、建基地、创品牌、强产业、富民生”的思路,以促进农业耕作优势转化为秦药资源生产优势、秦药资源优势转化为秦药产业优势、区位地理优势转化为秦药流通优势、科教人才优势转化为驱动发展优势为目标,实施以提质增效为核心的秦药资源种植、加工、制造、物流、大健康和“一带一路”品牌工程,培育药材大基地、秦药大品种、秦药大物流、健康大产业,提升秦药产业规模、核心竞争力、市场占有率、国内外知名度,从而构建完整的秦药产业发展模式,为推动落实秦药高质量发展提供决策参考。

关键词：秦药产业发展模式品牌路径