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Integrative Zoology 2022年第6期17卷 1041-1052页

作者： Xiaoning CHEN xiang HOU Tuo feng Ning HAN Jing WANG Gang CHANG Shaanxi Key Laboratory for Animal Conservation Shaanxi Institute of ZoologyXi’anChina College of Life Sciences Shaanxi Normal UniversityXi’anChina

The effect of combined levonorgestrel(P)and quinestrol(E)on the fertility of stripedﬁeld mouse(Apodemus agrarius)has not been evaluated.We performed a series of experiments in both the laboratory andﬁeld to assess the effect of P and/or E on the fertility of A.agrarius.In the laboratory,to test the time-dependent anti-fertility ef-fects of P and E,as well as their mixtures,90 male stripedﬁeld mice were randomly assigned to 6 treatment groups(n=60),and a control group(n=30).Mice in 3 treatment groups were administered 1 of the 3 compounds(1 mg�kg–1[body weight]EP-1,0.34 mg�kg–1 E,0.66 mg�kg–1 P)for 3 successive days(another half for 7 suc-cessive days)via oral gavage;mice were then sacriﬁced 15 and 45 days after initiating the gavage treatment.Ourﬁndings indicated that E and EP-1 treatment,but not P or control treatment,signiﬁcantly decreased the sperm count in the caudal epididymis,as well as the weight of the testes,epididymides,and seminal vesicles.Additionally,fer-tile female mice mated with E-and EP-1-treated males produced smaller pups.These data indicate that E and EP-1 can induce infertility in male A.agrarius.In theﬁeld,the population density of A.agrarius was signiﬁcantly inﬂu-enced by EP-1,and the rodent density in the treatment group was lower than that in the control group.Overall,our results indicate that EP-1 is an effective contraceptive in A.agrarius,a dominant rodent species in the farmland.

关键词： Apodemus agrarius fertility control levonorgestrel quinestrol

Attractor for the extensible beam equation with nonlocal weak damping on time–dependent space

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Acta Mathematica Sinica,English Series 2022年

作者： Chun xiang ZHAO feng Juan MENG Institute of Applied System Analysis Jiangsu University School of Mathematics and Physics Jiangsu University of Technology

In this article, we consider the long-time behavior of extensible beams with nonlocal weak damping: ε（t）utt + △u-m（ u 2）△u + ut put + f（u） = h, where ε（t） is a decreasing function vanishing at infinity. Within the theory of process on time-dependent spaces, we investigate the existence of the time-dependent attractor by using the Condition（Ct） method and more detailed estimates. The results obtained essentially improve and complete some previous works.

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Microstructural characteristics and deformation of magnesium alloy AZ31 produced by continuous variable cross-section direct extrusion

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Journal of Materials Science & Technology 2017年第6期33卷 573-579页

作者： Hongwei Jiang feng Li xiang Zeng School of Materials Science and Engineering Harbin University of Science and Technology

Magnesium（Mg） alloy AZ31 was produced by continuous variable cross-section direct extrusion（CVCDE）to study its deformation behavior. Metallographic microscopy（OM）, transmission electron microscopy（TEM）, and scanning electron microscopy（SEM） were used to observe the variations in microstructure and fracture morphology of Mg alloy AZ31 as a function of processing methods. The results reveal that grains of Mg alloy AZ31 were refined and their microstructure was homogenized by CVCDE. The recrystallization in Mg alloy AZ31 produced by CVCDE with 2 interim dies was more complete than that produced by conventional extrusion（CE） and CVCDE with 1 interim die, and the grains were finer and more uniform.Plasticity of the AZ31 alloy was improved. Fracture mode was evolved from a combination of ductility and brittleness to a sole ductile form. In summary, a CVCDE mold structure with 2 interim dies can improve microstructure, plasticity, and toughness of Mg alloy AZ31.

关键词： Continuous variable cross-section direct extrusion（CVCDE） Magnesium alloys Microstructural characteristics Plastic deformation

Nickel-catalyzed cross-electrophile C–Ge coupling of benzyl pivalates and chlorogermanes

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Science China Chemistry 2023年第12期66卷 3562-3566页

作者： Ming-xiang You Pei-feng Su Ze-Hui She Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry(SKLAOC) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

The C–Ge cross-coupling offers a promising approach for the precise synthesis of organogermanes. However, the current methods are primarily effective in the germylation of organo(pseudo)halides. This work demonstrates the possibility of transferring low-cost and easily available ester groups into organogermanes through the cleavage of stable C–O bonds. Primary,secondary, and even tertiary benzylic pivalates were coupled well with chlorogermanes. The reactions proceed under mild conditions. The scalability of this reaction and derivatization of the formed benzylgermanes are demonstrated.

关键词： nickel cross-coupling reductive coupling germanium germylation

An improved data space inversion method to predict reservoir state fields via observed production data

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Petroleum Science 2021年第4期18卷 1127-1142页

作者： Deng Liu xiang Rao Hui Zhao Yun-feng Xu Ru-xiang Gong Cooperative Innovation Center of Unconventional Oil and Gas(Ministry of Education&Hubei Province) Yangtze UniversityWuhan434023HubeiPR China School of Petroleum Engineering Yangtze UniversityWuhan434023HubeiPR China CNOOC Oilfield Services Co. Ltd.Tianjin30000PR China

A data-space inversion(DSI)method has been recently proposed and successfully applied to the history matching and production prediction of reservoirs.Based on Bayesian theory,DSI can directly and effectively obtain good posterior flow predictions without inversion of geological parameters of reservoir model.This paper presents an improved DSI method to fast predict reservoir state fields(e.***.saturation and pressure profiles)via observed production data.Firstly,a large number of production curves and state data are generated by reservoir model simulation to expand the data space of original DSI.Then,efficient history matching only on the observed production data is carried out via the original DSI to obtain related parameters which reflects the weight of the real reservoir model relative to prior reservoir models.Finally,those parameters are used to predict the oil saturation and pressure profiles of the real reservoir model by combining large amounts of state data of prior reservoir models.Two examples including conventional heterogeneous and unconventional fractured reservoir are implemented to test the performances of predicting saturation and pressure profiles of this improved DSI method.Besides,this method is also tested in a real field and the obtained results show the high computational efficiency and high accuracy of the practical application of this method.

关键词： Fossil fuels Oil and gas reservoirs Reservoir state fields Production data Data inversion method

Experiment on the silica sol imbibition of low-permeability rock mass:With silica sol particle sizes and rock permeability considered

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International Journal of Mining Science and Technology 2022年第5期32卷 1009-1019页

作者： Zhe xiang Nong Zhang Yiming Zhao Dongjiang Pan Xiaowei feng Zhengzheng Xie School of Mines Key Laboratory of Deep Coal Resource MiningMinistry of Education of ChinaChina University of Mining and TechnologyXuzhou 221116China School of Civil Engineering Xuzhou University of TechnologyXuzhou 221000China State Key Laboratory of Shield Machine and Boring Technology Zhengzhou 450001China

It’s a universal engineering problem to seal micro-cracks of low-permeability argillaceous rock mass by grouting in the fields of civil engineering and mining.This paper achieved the grouting sealing of lowpermeability artificial rocks with the permeability of 0.1–40 mD by adopting silica sol imbibition grouting.The variation characteristics of particle size,viscosity,and contact angle of silica sol during solidification and the pore size distribution of low-permeability artificial rocks were measured,and spontaneous imbibition tests of the artificial rocks were carried out.Finally,combined with the imbibition theory,percolation theory,and fracture medium grouting principle,the silica sol imbibition mechanism of lowpermeability rocks and soil was discussed.The results show that:(1)Silica sol can be injected into artificial rocks with the minimum permeability of 0.1 mD through spontaneous imbibition;(2)The particle size increase of silica sol leads to decreased wettability,affinity,and injectability in grouting materials;and(3)In the range of 0.1–40 mD,the grout absorption first increases and then decreases with increased permeability.The number of large pores and fractures in the rock mass is related to injectability,and the number of small and medium pores is related to the internal driving force of imbibition.This study provides a theoretical basis for silica sol grouting sealing of low-permeability argillaceous rocks and is,therefore,an important reference for application.

关键词： Low permeability artificial rock Pore size distribution Silica sol Imbibition grouting Injectability

Effect of rare earth on primary carbides in H13 die steel and their addition method:a review

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Journal of Iron and Steel Research(International) 2024年第3期31卷 531-551页

作者： Jing-feng Wang Lin-zhu Wang Chao-yi Chen xiang Wang Fei Zhao School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina Zhengzhou Railway Vocational and Technical College Zhengzhou 450000HenanChina Guizhou Provincial University Key Laboratory of High Performance Battery Materials Guizhou UniversityGuiyang 550025GuizhouChina Shougang Guiyang Special Steel Co. Guiyang 550005GuizhouChina

Larger-sized primary carbides lead to stress concentration during the application of H13 hot-work die steel,resulting in microcracks and fatigue failure.Rare earth was usually added to modify the carbides and inclusions.The existing literature is reviewed on the effect of rare earth on primary carbides in H13 steel.A comprehensive review on the effect of rare earth on the characteristics of primary carbides,i.e.,number,size,morphology,and thermal stability in H13 steel,was done.The precipitation mechanism and nucleation of primary carbides with rare earth were summarized.The position and form of rare earth in steel and their effects on alloying elements segregation were reviewed.The addition techniques of rare earth in H13 steel were compared,and the prospects for other uncommon rare earth and emerging technology were present.Based on the current references,it can be known that adding rare earth facilitated refined and dispersed primary carbides.The size of primary carbides would be reduced,and their morphology would be improved because the rare earth inclusions formed in H13 steel can act as nucleation cores forγ-Fe orδ-Fe,refining the dendritic structure.Besides,the number of primary carbides at grain boundaries would be significantly reduced.However,rare earth had little impact on thermal stability.The nucleation of primary carbides tended to be inhibited due to the modification of inclusions by rare earth which were likely to be nucleation cores for primary carbides.Rare earth had been reported to affect the mechanism and process of primary carbide precipitation.Additionally,the addition of rare earth can inhibit the segregation of alloying elements and carbon diffusion by calculation.Thus,laboratory experiments and theoretical calcu-lations need to be conducted to study the states and evolution of rare earth steels.

关键词： Rare earth H13 die steel Primary carbide Nucleation Dendritic structure

Clinical practice of sepsis-induced immunosuppression:Current immunotherapy and future options

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Chinese Journal of Traumatology 2024年第2期27卷 63-70页

作者： Fei Pei Bin Gu Shu-Min Miao xiang-Dong Guan Jian-feng Wu Department of Critical Care Medicine The First Affiliated HospitalSun Yat-sen UniversityGuangzhou510080China Guangdong Clinical Research Center for Critical Care Medicine Guangzhou510080China

Sepsis is a potentially fatal condition characterized by the failure of one or more organs due to a disordered host response to infection.The development of sepsis is closely linked to immune dysfunction.As a result,immunotherapy has gained traction as a promising approach to sepsis treatment,as it holds the potential to reverse immunosuppression and restore immune balance,thereby improving the prognosis of septic patients.However,due to the highly heterogeneous nature of sepsis,it is crucial to carefully select the appropriate patient population for immunotherapy.This review summarizes the current and evolved treatments for sepsis-induced immunosuppression to enhance clinicians'understanding and practical application of immunotherapy in the management of sepsis.

关键词： Sepsis Sepsis-induced immunosuppression Immunotherapy Enrichment Classifier

High valence state of Ni and Mo synergism in NiS_(2);MoS_(2)hetero-nanorods catalyst with layered surface structure for urea electrocatalysis

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Journal of Energy Chemistry 2022年第3期31卷 483-492,I0013页

作者： Shuli Wang Linyu Zhao Jiaxin Li Xinlong Tian xiang Wu Ligang feng School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002JiangsuChina State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikou 570228HainanChina School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

High valence state species are significant in the energy-relevant electrochemical oxidation reactions.Herein,the high active state of Ni^(3+)formation induced by Mo^(6+)and their efficient synergism in NiS_(2)-MoS_(2)hetero-nanorods powder catalyst with the rough layered structure are demonstrated,as proof of concept,for the urea-assisted water electrolysis.This catalyst can be derived from the sulfidation of NiMoO_(4) nanorods that can realize individual metal sulfides sufficiently mixing at a domain size in the nanoscale which creates lots of active sites and nanointerfaces.The high valence state of Mo^(6+)and Ni^(3+)formation and increased conductive phase of 1 T MoS_(2)in the hetero-nanorods compared to the counterpart pure phases are revealed by spectral study and microscopic analysis;high electrochemical surface area and active site exposure are found due to the nano-interface formation and layered rough nanosheets over the surface of nanorods.They show much higher catalytic performance than their pure phases for urea oxidation,including high catalytic activity,stability,charge transfer ability and catalytic kinetics resulting from more active Ni^(3+)species formation and electronic synergism of high valence metals.Transformation of 1 T MoS_(2)to Mo^(6+)and increased amount of Mo^(6+)and Ni^(3+)after stability test indicate their involvement and synergism for the catalysis reaction.The current work offers a novel understanding of the synergistic effect based on the high valence state synergism for heterogeneous catalysts in electrocatalysis.

关键词： Hetero-nanorods High valence state Urea oxidation NiS_(2) MoS_(2)

Effect of endostar combined with cisplatin on expression of VEGF and Sema3A of Lewis lung cancer rats

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Asian Pacific Journal of Tropical Medicine 2013年第1期6卷 57-60页

作者： Ping feng Zhi-Lin Zhang Zhi-Hua Zhang Xiu-Long Zhang Feng xiang Jian-Hua Tang Bao-Li xiang Master of Respiratory Medicine Hebei Northern College Department of Respiratory Medicine First Affiliated Hospital of Hebei Northern College Department of Clinical Pharmacology First Affiliated Hospital of Hebei Northern College

Objective:To evaluate the therapeutic effect of endostar(ED) combined with cisplatin(DDP) on model of C57BL/6 rats,and to further investigate the inhibiting mechanism of endostar from tumor angiogenesis.Methods:Lewis lung cancer cells were inoculated in C57BL/6 mouse,then the mouse were randomized into control group(group A),ED(group B),DDP(group C) and ED/DDP (group D).They were treated according to the plan.And the expressions of VEGF and Sema3A were evaluated by immunhistochemisty.Results:The weight of tumor increased in group A and B.It was decreased in group C and D.The tumor volume was increased in all the 4 groups. The VEGF expression of group D was obviously lower than the other group 3,but the Sema3A expressed of group D was significantly strengthener than the other group 3.The VEGF expression of group B and group D were obviously low especially in the 4th-8th days.Pearson correlated analysis showed that the expression VEGF and Sema3A were negatively correlated(r=-0.72, P<0.05).Conclusions:ED combined with DDP could control the tumor growth effectively,and avoid weight loss.ED could reduce VEGF expression,and enhance Sema3A expression.Tumor vessel presents transient normalization.It is easy for DDP perfusion,and to kill tumor cells.

关键词： Lewis lung cancer Endostar DDP VEGF Sema3A