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Defence Technology（防务技术） 2022年第3期18卷 509-523页

作者： Yue Zhang Xin jiang Zheng-feng Bai jia-wen guo Cheng Wei School of Space Science and Technology Xidian UniversityXi'an710126China School of Astronautics Harbin Institute of TechnologyHarbin150001China Department of Mechanical Engineering Harbin Institute of TechnologyWeihai264209China

The tether deployment of a tethered satellite system involves the consideration of complex dynamic properties of the tether,such as large deformation,slack,and even rebound,and therefore,the dynamic modelling of the tether is necessary for performing a dynamic analysis of the *** a variablelength tether element,the absolute nodal coordinate formulation(ANCF)in the framework of the arbitrary Lagrange-Euler(ALE)description was used to develop a precise dynamic model of a tethered *** model considered the gravitational gradient force and Coriolis force in the orbital coordinate frame,and it was validated through numerical *** the presence of dynamic constraints,a deployment velocity of the tether was obtained by an optimal *** the simulation,rebound behavior of the tethered satellite system was observed when the ANCF-ALE model was ***,the rebound behavior cannot be predicted by the traditional dumbbell ***,an improved optimal deployment velocity was *** results indicated that the rebound phenomenon was eliminated,and smooth deployment as well as a stable state of the station-keeping process were ***,the swing amplitude in the station-keeping phase decreased when a deployment strategy based on the improved optimal deployment velocity was used.

关键词： Tethered satellite system Dynamic model Rebound Deployment ANCF-ALE

Male nutritional status does not impact the reproductive potential of female Cnaphalocrocis medinalis moths under conditions of nutrient shortage

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Insect Science 2022年第2期29卷 467-477页

作者： jia-wen guo Yu Cui Pei-Jiong Lin Bao-Ping Zhai Zhong-Xian Lu Jason W.Chapman Gao Hu State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products Institute of Plant Protection and MicrobiologyZhejiang Academy of Agricultural SciencesHangzhou310021 China Department of Entomology College of Plant ProtectionNanjing Agricultural UniversityNanjing210095 China Centre for Ecology and Conservation and Environment and Sustainability InstituteUniversity of ExeterCornwallPenrynTR109FE UK

In addition to sperm,some accessory substances transferred to females during copulation act as nuptial gifts by passing on valuable nutrients in many insect *** nutritional status of the males can thus have a great effect on the mating behavior,fecundity and even the longevity of ***,little is known about the effect of male nutritional status on the female reproductive traits in migratory insect species,particularly when females experience nutrient shortage and have to choose between reproduction and ***,Cnaphalocrocis medinalis,a migratory rice pest in Asia,was studied to explore this *** results showed that in male moths fed with honey solution,their gonads had higher energy content than gonads of starved males,resulting in increased energy content of the bursa copulatrix of females after mating with fed *** females showed increased mating frequency,fecundity and longevity compared to females mating with starved males,indicating that male moths deliver nuptial gifts to females and improve their reproductive ***,when females were starved,only about 45%mated,with just a single copulation,regardless of male nutritional *** females showed lower fecundity,and a longer pre-oviposition period(indicating a greater propensity to migrate),compared to fed ***,copulation still significantly extended their *** results suggest that starved females invest in migration to escape deteriorating habitats,rather than investing the nuptial gift to increased *** results further our understanding of the reproductive adaptability of migratory insects under conditions of food stress.

关键词： bursa copulatrix Cnaphalocrocis medinalis insect migration nuptial gifts spermatophore

A mini review on oxidative dehydrogenation of propane over boron nitride catalysts

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Petroleum Science 2023年第4期20卷 2488-2498页

作者： Zhu Fu De-Zheng Li Li-Dai Zhou Yu-Ming Li jia-wen guo Yu-Qiao Li Hui-Min Liu Qi-jian Zhang School of Chemical and Environmental Engineering Liaoning University of TechnologyJinzhouLiaoning121001China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China

Oxidative dehydrogenation of propane is an attractive route for the synthesis of propylene due to its favorable thermodynamic and kinetic characteristics, however, it is challenging to realize high selectivity towards propylene. Recently, it has been discovered that boron nitride (BN) is a promising catalyst that affords superior selectivity towards propylene in oxidative dehydrogenation of propane. Summarizing the progress and unravelling the reaction mechanism of BN in oxidative dehydrogenation of propane are of great significance for the rational design of efficient catalysts in the future. Herein, in this review, the underlying reaction mechanisms of oxidative dehydrogenation of propane over BN are extracted;the developed BN catalysts are classified into pristine BN, functionalized BN, supported BN and others, and the applications of each category of BN catalysts in oxidative dehydrogenation of propane are summarized;the challenges and opportunities on oxidative dehydrogenation of propane over BN are pointed out, aiming to inspire more studies and advance this research field.

关键词： Oxidative dehydrogenation of propane Boron nitride Propylene Reaction mechanism

Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： Jing-Lei Huang guo-Bin jia Li-Feng Han wen-Qian Liu Li Huang Zheng-Han Yang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power *** model considers the impact of thermal properties of fluid variation on accuracy and has been validated with *** study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet ***,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also *** results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial *** simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

Middle Devonian ostracods from Jiwozhai patch reef(Dushan,Guizhou Province,South China):Biostratigraphic and palaeoecological implication

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Journal of Palaeogeography 2024年第3期13卷 581-593页

作者： Jun-Jun Song jia-Yuan Huang wen guo Kun Liang Yu-Cong Sun Zhi-Hong Wang wen-Kun Qie State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008Jiangsu ProvinceChina Hubei Key Laboratory of Paleontology and Geological Environment Evolution Wuhan Center of China Geological SurveyWuhan 430205Hubei ProvinceChina University of Chinese Academy of Sciences NanjingNanjing 211135Jiangsu ProvinceChina

The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.

关键词： Ostracods Givetian Jiwozhai patch reef Dushan Palaeoecology

Vertically aligned montmorillonite aerogel-encapsulated polyethylene glycol with directional heat transfer paths for efficient solar thermal energy harvesting and storage

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 907-916页

作者： Qijing guo Cong guo Hao Yi Feifei jia Shaoxian Song Key Laboratory of Green Utilization of Critical Non-metallic Mineral Resources Ministry of EducationWuhan University of TechnologyWuhan 430070China School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China Hubei Key Laboratory of Mineral Resources Processing and Environment Wuhan University of TechnologyWuhan 430070China

The conversion and storage of photothermal energy using phase change materials(PCMs)represent an optimal approach for harnessing clean and sustainable solar ***,we encapsulated polyethylene glycol(PEG)in montmorillonite aerogels(3D-Mt)through vacuum impregnation to prepare 3D-Mt/PEG composite *** used as a support matrix,3D-Mt can effectively prevent PEG leakage and act as a flame-retardant barrier to reduce the flammability of ***,3D-Mt/PEG demonstrates outstanding shape retention,increased thermal energy storage density,and commendable thermal and chemical *** phase transition enthalpy of 3D-Mt/PEG can reach 167.53 J/g and remains stable even after 50 heating-cooling ***,the vertical sheet-like structure of 3D-Mt establishes directional heat transport channels,facilitating efficient phonon *** configuration results in highly anisotropic thermal conductivities that ensure swift thermal responses and efficient heat *** study addresses the shortcomings of PCMs,including the issues of leakage and inadequate flame *** achieves the development and design of 3D-Mt/PEG with ultrahigh strength,superior flame retardancy,and directional heat ***,this work offers a design strategy for the preparation of high-performance composite *** 3D-Mt/PEG with vertically aligned and well-ordered array structure developed in this research shows great potential for thermal management and photothermal conversion applications.

关键词： montmorillonite aerogel polyethylene glycol phase change materials solar thermal energy storage flame retardant

Protein crystallization with DNA templates

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Particuology 2024年第3期86卷 262-268页

作者： Bo Zhang jia Yu Zhe Pu wenhui guo Ruoqi Yang Yu wen Zhijiang Rong Hui Wang Xiaoli Wu Bo Wang Hongyan Sun School of Environment and Resources Taiyuan University of Science and TechnologyTaiyuan030024China School of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein *** is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization *** is biologically compatible and artificially designable polymer,which is easy to *** this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and ***-fluence of DNA,single-stranded DNA with 10,20,40 bases and double-stranded DNA with 10,20,40 base pairs,were *** success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates ***-stranded DNA led to higher nucleation rate than that with single-stranded *** promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA *** number and crystallization rate was enhanced with addition of long double-stranded DNA *** the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： DNA Polymer Additive Protein Crystallization

In situ embedded bismuth nanoparticles among highly porous carbon fibers for efficient carbon dioxide reduction

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Rare Metals 2024年第9期43卷 4312-4320页

作者： Wei-jian guo Ao Zhou wen-wen Cai Jin-Tao Zhang Key Laboratory for Colloid and Interface Chemistry (Ministry of Education) School of Chemistry and Chemical EngineeringShandong University

Electrocatalysis provides an optimal approach for the conversion of carbon dioxide(CO2) into high-value chemicals, thereby presenting a promising avenue toward achieve carbon neutrality. However, addressing the selectivity and stability challenges of metal catalysts in electrolytic reduction remains a daunting task. In this study, the electrospinning method is employed to fabricate porous carbon nanofibers loaded with bismuth nanoparticles with the help of in situ pyrolysis. The porous carbon nanofibers as conductive support would facilitate the dispersion of bismuth active sites while inhibiting their aggregation and promoting the mass transfer, thus enhancing their electrocatalytic activity and stability. Additionally, nitrogen doping induces electron delocalization in bismuth atoms through metal-support interactions, thus enabling efficient adsorption of intermediates for improving selectivity based on the theoretical calculation. Consequently, Bi@PCNF-500 exhibits the exceptional selectivity and stability across a wide range of potential windows. Notably, its faradaic efficiency(FE) of formate reaches 92.7% in H-cell and94.9% in flow cell, respectively, with good electrocatalytic stability. The in situ characterization and theoretical calculations elucidate the plausible reaction mechanism to obtain basic rules for designing efficient electrocatalyst.

关键词： Carbon dioxide reduction Electron delocalization N-doping Porous carbon nanofiber

Endoscopic ultrasound-guided lauromacrogol injection for treatment of colorectal cavernous hemangioma:Two case reports

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 966-973页

作者： Hua-Tuo Zhu wen-guo Chen Jing-Jie Wang jia-Nan guo Fen-Ming Zhang guo-Qiang Xu Hong-Tan Chen Department of Gastroenterology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Colorectal cavernous hemangioma is a rare vascular malformation resulting in recurrent lower gastrointestinal hemorrhage,and can be misinterpreted as *** resection is currently the mainstay of treatment,with an emphasis on sphincter *** SUMMARY We present details of two young patients with a history of persistent hematochezia diagnosed with colorectal cavernous hemangioma by endoscopic ultrasound(EUS).Cavernous hemangioma was relieved by several EUS-guided lauromacrogol injections and the patients achieved favorable clinical *** Multiple sequential EUS-guided injections of lauromacrogol is a safe,effective,cost-efficient,and minimally invasive alternative for colorectal cavernous hemangioma.

关键词： Endoscopic ultrasound Lauromacrogol injection Colorectal cavernous hemangioma Case report

Spontaneous Infection and Periodic Evolving of Domain in a Diffusive SIS Epidemic Model

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 164-191页

作者： Qiang wen guo-qiang Ren Bin Liu School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan430074China

In this paper, we consider a susceptible-infective-susceptible(SIS) reaction-diffusion epidemic model with spontaneous infection and logistic source in a periodically evolving domain. Using the iterative technique,the uniform boundedness of solution is established. In addition, the spatial-temporal risk index R0(ρ) depending on the domain evolution rate ρ(t) as well as its analytical properties are discussed. The monotonicity of R0(ρ)with respect to the diffusion coefficients of the infected dI, the spontaneous infection rate η(ρ(t)y) and interval length L is investigated under appropriate conditions. Further, the existence and asymptotic behavior of periodic endemic equilibria are explored by upper and lower solution method. Finally, some numerical simulations are presented to illustrate our analytical results. Our results provide valuable information for disease control and prevention.

关键词： diffusive SIS model spontaneous infection periodically evolving domain periodic endemic equilibrium