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Estrogen-Induced Uterine Vasodilation in Pregnancy and Preeclampsia

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Maternal-Fetal Medicine 2022年第1期4卷 52-60页

作者： Yan Li baoshi Han Alejandra Garcia Salmeron Jin Bai Dong-bao Chen Translational Medical Research Centre The First Flospital Affiliated to Shandong First Medical University and Shandong Provincial Qianfoshan HospitalJinanShandong 250014China Center for Reproductive Medicine Shandong UniversityThe Key Laboratory of Reproductive Endocrinology of Ministry of EducationNational Research Center for Assisted Reproductive Technology and Reproductive GeneticsJinanShandong 250014China Department of Obstetrics and Gynecology University of CaliforniaIrvineCA 92697USA

Normal pregnancy is associated with dramatically increased estrogen biosynthesis whose role is believed to raise uterine blood flow to facilitate the bi-directional maternal-fetal exchanges of gases(O_(2) and CO_(2)),to deliver nutrients,and exhaust wastes to support fetal development and survival.Constrained uterine blood flow in pregnancy is a leading cause of preeclampsia with fetal growth restriction,rendering investigations of uterine hemodynamics to hold a high promise to inform pathways as targets for therapeutic interventions for preeclampsia.The mechanisms of estrogen-induced uterine vasodilation in pregnancy have long been attributed to enhanced endothelium production of nitric oxide,but clinical trials targeting this pathway that dominates uterine hemodynamics have achieved no to little success.Emerging evidence has recently shown a novel proangiogenic vasodilatory role of hydrogen sulfide in regulating uterine hemodynamics in pregnancy and preeclampsia,provoking a new field of perinatal research in searching for alternative pathways for pregnancy disorders especially preeclampsia and intrauterine growth restriction.This minireview is intended to summarize the nitric oxide pathway and to discuss the emerging hydrogen sulfide pathway in modulating estrogen-induced uterine vasodilation in pregnancy and preeclampsia.

关键词： Estrogens Uterine vasodilation Nitric oxide Hydrogen sulfide Pregnancy Preeclampsia

Effect of removing Al and Ti elements on peak flow stress of nickel-based heat-resistant alloy 617

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Journal of Iron and Steel Research(International) 2023年第2期30卷 384-391页

作者： chen dong Zheng-zong chen Zheng-dong Liu Han-sheng bao Zhen Liu Zheng-jun Wang Faculty of Mechanical and Material Engineering Huaiyin Institute of TechnologyHuaian223003JiangsuChina Jiangsu Key Laboratory of Advanced Manufacturing Technology Huaiyin Institute of TechnologyHuaian223003JiangsuChina Institute for Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing100081China

The hot deformation behavior and the microstructure characteristics of alloy 617 and alloy C-HRA-2 were compared and analyzed.The removal of Al and Ti elements has a significant change in the hot deformation of the alloy,and there are two opposite effects on the flow stress before and after recrystallization.The results show that the removal of Al and Ti elements increases the flow stress of the alloy under high temperature or low strain rate deformation conditions.This is mainly due to the increase in the stacking fault energy of the alloy so that the alloy contains a higher twin boundary fraction after dynamic recrystallization(DRX).However,before DRX occurs,that is,at low temperature and high strain rate,the flow stress of this alloy is relatively reduced.This is due to the reduction in Peierls-Nabarro stress,making the alloy more prone to dislocation slip.

关键词： Peak flow stress Nickel-based heat-resistant alloy Slip band Stacking fault energy

Power Synchronization Compensation Strategy Based on Second-order Compensation Links for Voltage-controlled Inverters in Microgrids

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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1935-1947页

作者： Jiawei dong Chunyang Gong Jun bao Lihua Zhu Hui chen Zhixin Wang School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Shanghai University of Electrical Power ShanghaiChina Shanghai Xilong Solar Energy Technology Co. Ltd.ShanghaiChina Shanghai Chint Power Systems Co. Ltd.ShanghaiChina College of Automation Engineering Shanghai University of Electric PowerShanghaiChina

A second-order compensation link is adopted to control voltage-controlled inverters(VCIs) in microgrid systems to enhance the performance of the power synchronization process of the inverter. The second-order compensation link is classified as both a real pole compensator(RPC) and a complex pole compensator(CPC) according to the pole position. Given a model for the VCI power output, the design process for the second-order compensation link, which is equipped with an RPC and a CPC, is detailed. Moreover, the frequency-domain compensation effects of the RPC and CPC are analyzed using the root locus and Bode diagrams of the system before and after compensation. Finally, the compensation effects of the two types of second-order compensators are compared with the commonly used high-pass filter using MATLAB/Simulink, which verifies the RPC and CPC strategies. Simulation results show that the two types of compensators designed in this study can effectively increase the system cutting frequency and improve the phase margin in the frequency domain while accelerating the power synchronization process, simultaneously making it smoother and reducing overshoot in the time domain. The RPC has better gain robustness, whereas the CPC has better time constant robustness. By implementing an RPC or a CPC, the dynamic time of the power synchronization compensation strategy is reduced within 0.5 s, and the overshoot is reduced within 10% in the experiments with two inverters.

关键词： Frequency-domain analysis power synchronization second-order compensation link stability voltage-controlled inverter(VCI) microgrid

Mechanism of high temperature reduction on iron carbide preparation with low-grade siderite

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Journal of Iron and Steel Research(International) 2022年第9期29卷 1357-1367页

作者： dong chen Ya-nan Lv Wei Zhao Fei-bao Wu Wei-ang Ying School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina Department of Mechanical and Electrical Engineering Suzhou Institute of Industrial TechnologySuzhou 215104JiangsuChina

The carburization roasting followed by magnetic separation is a feasible method to utilize low-grade siderite ore.In order to enhance the carburization efficiency and separation effciency,high temperature reduction was carried out,and its mechanism was demonstrated by measuring carburization index,phase change,and microstructure under a carbon-sulfur infrared analyzer,an X-ray diffractometer,and a metallurgical microscope.The results show that both the carburization effciency of siderite pellet and the separation efficiency of iron carbide from gangue are very low.However,high temperature reduction is a useful way to enhance the carburization efficiency,as it can accelerate the reduction reaction rate and carburization reaction rate.Furthermore,high temperature reduction can improve the growth of iron carbide particle,promote the carburization efficiency,and strengthen the sodium modification reactions,thereby greatly accelerating the separation efficiency of iron carbide and gangue.When the siderite pellets were reduced at 1050℃ for 90 min and carburized at 650℃ for 120 min,the carburization index of carburized pellets reached 36.06.After magnetic separation treatment,an electric furnace burden assaying 83.12 wt.%Fe and 6.96 wt.%C was prepared,and the corresponding iron recovery rate was 95.43%.The high temperature reduction is promisingly adopted to promote the utilization of low-grade siderite ores using carburization-magnetic separation technology.

关键词： Siderite High temperature reduction Carburization-Separation Iron carbide

Flat Frequency Comb Generation Based on Efficiently Multiple Four-Wave Mixing Without Polarization Control

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Photonic Sensors 2016年第1期6卷 85-89页

作者： Qimeng dong bao SUN Fushen chen Jun JIANG Key Laboratory of Optical Fiber Sensing & Communications (Ministry of Education) University of Electronic Science and Technology of China Chengdu 611731 China

这份报纸为完全光的频率梳子(OFC ) 论述一种新技术产生，它基于多重四波浪的混合的非线性的过程(FWM ) 效果。非线性的效果被使用由单个模式纤维(SMF ) 组成的建议光反馈计划显著地提高，二高度非线性的纤维(HNLF ) 与不同零分散波长(Z... 详细信息

这份报纸为完全光的频率梳子(OFC ) 论述一种新技术产生，它基于多重四波浪的混合的非线性的过程(FWM ) 效果。非线性的效果被使用由单个模式纤维(SMF ) 组成的建议光反馈计划显著地提高，二高度非线性的纤维(HNLF ) 与不同零分散波长(ZDW ) 和极化横梁 splitters (PBS ) 。模拟结果说明它在 6-dB 力量偏差以内由仅仅 20 GHz 扩展一把梳子到 128 协调的线 spaced 的效率和适用性。

关键词：下线服务迁移

Effects of long term aging on microstructure and properties of a tungsten bearing heat resistant alloy

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Journal of Iron and Steel Research(International) 2020年第4期27卷 477-487页

作者： Han-sheng bao Gang Yang Zheng-zong chen Zheng-dong Liu Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The effects of long-term aging at 700 and 750℃ on microstructure and mechanical properties of a new developed tungsten bearing heat-resistant alloy used for advanced ultra-supercritical power plant was investigated both experimentally and thermodynamically.Experimental results showed that the mechanical properties maintained excellent stability after long-term aging at 700℃ for 10,000h,while the impact absorbing energy decreased sharply after 1000-h aging and then kept constant till 10,000h.The main precipitates after long-term aging at 700 and 750℃ were M23C6,MC and homogeneous γ′-phases.The mass fraction of M23C6 carbides increased with increasing aging time,and M23C6 carbides precipitated in shape of chains and lamellas on grain boundaries.The slight decrease in MC carbides during aging may be due to degradation reaction.The weight fraction of γ′-phase increased with the aging time,and then changed little after 5000h;γ′-phase exhibited excellent microstructure stability and low coarsening rate during long-term aging at 700℃.However,the coarsening rate of γ′-phase was much higher at 750℃.

关键词： Tungsten Long-term aging Heat-resistant alloy gama′-phase Coarsening rate

Kinetic Characteristics Analysis of Aircraft During Heavy Cargo Airdrop

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International Journal of Automation and computing 2014年第3期11卷 313-319页

作者： Jie chen Cun-bao Ma dong Song School of Aeronautics Northwestern Polytechnical University

Airdrop is the most important approach for crisis transaction and unexpected events, it is necessary to investigate the flight characteristics of transport aircraft during the dropping process. This paper mainly focuses on the stability, controllability and model simplification of large aircraft with heavy cargo airdrop. In this process, the primary elements which have impact on force and moment are studied theoretically, the role of cargo mass, moving parameters and other factors on dynamical characteristics have been assessed by simulation and analysis. And then the aircraft model simplification is completed for control system designing in future.All the work above shows that the parameters of cargo moving play a dominant role in flight characteristics and the flight equations can be simplified to reduce the design complexity.

关键词： Modeling,simulation,control of aircraft,kinematics and dynamics of machines,model reduction

Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su Ze-Yu Li Li-Le Liu Guo-Xiang dong Xiao-bao Wang Yong-Jing chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

Optimizing sludge dewatering with a combined conditioner of Fenton’s reagent and cationic surfactant

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Journal of Environmental Sciences 2020年第2期32卷 21-30页

作者： dong-Qin He Jing-Yi chen Bo bao Xiang-Liang Pan Jun Li chen Qian Han-Qing Yu Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province College of EnvironmentZhejiang University of TechnologyHangzhou 310014China CAS Key Laboratory of Urban Pollutant Conversion Department of Applied ChemistryUniversity of Science&Technology of ChinaHefei 230026China

Enhancing sludge dewatering is of importance in reducing environmental burden and disposal costs.In this work, a cationic surfactant, cetyl trimethyl ammonium bromide(CTAB), was combined with Fenton’s reagent for sludge dewatering.Results show that the Fenton-CTAB conditioning significantly promotes the sludge dewatering.Using combined techniques of response surface methodology and uniform design, dosages of Fe2+, H2O2, and CTAB for water content response were optimized to be 89, 276, and 233 mg/g dry solids(DS),respectively.The water content of sludge decreased from 79.0% to 66.8% under the optimal conditions.Compared with cationic polyacrylamide, the Fenton-CTAB system exhibited superior sludge dewatering performance.To gain insights into the mechanisms involved in sludge dewatering, the effects of Fenton-CTAB conditioning on the composition of extracellular polymeric substances(EPS) and the morphology of the sludge flocs were investigated.The decomposition of EPS into some dissolved organics and the release of proteins in tightly bound EPS facilitated the conversion of bound water to free water and further reduced the water content of sludge cake.After conditioning, morphology of sludge showed aggregation.Overall, the enhanced sludge dewatering by Fenton-CTAB treatment provides an efficient way for management of sewage sludge.

关键词： Sludge dewatering Fenton reaction Cationic surfactant–CTAB Extracellular polymeric substances Uniform design