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On the Intelligent Optimization of the Crevice Structure in a Rapid Compression Machine

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Journal of Thermal Science 2024年第3期33卷 1200-1215页

作者： guo qiang LIU Jie WU Yingtao WANG Hewu TANG Chenglong YU Ruiguang Department of Power Mechanical Engineering Beijing Jiaotong UniversityBeijing100044China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing100084China Beijing Key Laboratory of New Energy Vehicle Powertrain Technology Beijing100044China National International Science and Technology Cooperation Base Beijing Jiaotong UniversityBeijing100044China

In this study,the multi-objective intelligent optimization of the crevice structure in a rapid compression machine(RCM)is carried out based on the RCM simulation model modified with the KIVA-3V program.A multi-objective optimization simulation model of the crevice structure based on the large eddy simulation model coupled with the genetic algorithm NSGA-Ⅲis *** optimization parameters and seven optimization objectives are selected in the optimization *** results show that the genetic algorithm can quickly find the values of the optimized *** crevice volume ratio shows a trade-off relationship with the dimensionless temperature ratio T_(max)/T_(aver)and the tumble ratio.A larger crevice volume can reduce the flow of boundary layer cryogenic gas into the combustion chamber,thus improving the temperature *** addition,the crevice entrance width and the connecting channel length should be smaller,while the volume of the crevice main chamber should be larger,so as to sufficiently introduce the low-temperature gas of the boundary layer into the crevice and reduce their influence on the temperature field of the combustion *** the crevice volume accounts for10%of the total volume,the temperature uniformity of the combustor is significantly enhanced,and when the crevice volume accounts for 30.4%,there is almost no low-temperature vortex in the combustion chamber.

关键词： rapid compression machine adiabatic core area ignition delay period crevice structure

Colo-colonic intussusception as a rare complication of colonoscopy with polypectomy: Two case reports

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1939-1947页

作者： Sai-Heng Xiang guo-qiang Xu Department of Gastroenterology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Colonoscopy is the most frequently used diagnostic and therapeutic tool for the treatment of colorectal *** the complication rate is low,it can be potentially *** is a rare and severe complication often associated with *** a handful of post-colonoscopy intussusception cases have been reported,making this study a valuable addition to the medical *** SUMMARY Case 1:A 61-year-old man underwent colonoscopy with polypectomy for chronic abdominal *** patient experienced abdominal pain 11 hours later but was still discharged after pain *** was readmitted due to recurring *** tomography(CT)showed colo-colonic *** conservative management and attempts at endoscopic reduction failed;therefore,laparoscopic right hemicolectomy was *** examination revealed tubular adenomas in the polyps and inflammation in the resected *** 2:A 59-year-old woman underwent colonoscopy with polypectomy for a polyp in the transverse *** experienced upper abdominal pain,fever,nausea,and vomiting 9 hours after the *** CT and blood tests revealed a colo-colonic intussusception near the hepatic flexure and an elevated white blood cell *** attempts at endoscopic reduction failed and conservative treatment showed no *** underwent successful laparoscopic reduction and recovered *** examination of the resected polyp revealed *** Post-colonoscopy intussusception in adults is rare,and polypectomy may contribute to its *** diagnosis is crucial,with prompt CT examination serving as *** excluding malignancies,conservative management and reduction of intussusception should be considered before surgical bowel resection.

关键词： Intussusception Colonoscopy Polypectomy Complication Case report

Conjugate Vectors Method Applied to Asymmetrical Fault Analysis of Power Electronized Power Systems

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1536-1549页

作者： Yingbiao Li xing Liu Jiabing Hu Jianhang Zhu Jianbo guo State Key Laboratory of Advanced Electromagnetic Technology(Huazhong University of Science and Technology) Wuhan 430074China China Electric Power Research Institute Beijing 100192China

With the wide application of power electronized resources(PERs),the amplitude and frequency of voltages show significant time-varying characteristics under asymmetrical *** a result,the traditional phasor model,impedance model,and symmetrical components method based on the constant amplitude and frequency of voltages are facing great ***,a novel asymmetrical fault analysis method based on conjugate vectors is proposed in this paper which can meet the modeling and analysis requirements of the network excited by voltages with time-varying amplitude/***,asymmetrical fault characteristics are *** an application,a faulted phase identification(FPI)strategy is proposed based on the fault *** correctness and superiority of the asymmetrical fault analysis method and FPI strategy are verified in time-domain simulations and a real-time digital simulator.

关键词： Asymmetrical fault characteristics conjugate vectors method dynamic asymmetrical fault analysis time-varying amplitude/frequency

Runout prediction of potential landslides based on the multi-source data collaboration analysis on historical cases

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China Geology 2024年第2期7卷 264-276页

作者： Jun Sun Yu Zhuang Ai-guo xing Guizhou Geology and Mineral Engineering Construction Co. LtdGuiyang 550000China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Long runout landslides involve a massive amount of energy and can be extremely hazardous owing to their long movement distance,high mobility and strong destructive *** methods have been widely used to predict the landslide runout but a fundamental problem remained is how to determine the reliable numerical *** study proposes a framework to predict the runout of potential landslides through multi-source data collaboration and numerical analysis of historical landslide ***,for the historical landslide cases,the landslide-induced seismic signal,geophysical surveys,and possible in-situ drone/phone videos(multi-source data collaboration)can validate the numerical results in terms of landslide dynamics and deposit features and help calibrate the numerical(rheological)***,the calibrated numerical parameters can be used to numerically predict the runout of potential landslides in the region with a similar geological setting to the recorded *** of the runout prediction approach to the 2020 Jiashanying landslide in Guizhou,China gives reasonable results in comparison to the field *** numerical parameters are determined from the multi-source data collaboration analysis of a historical case in the region(2019 Shuicheng landslide).The proposed framework for landslide runout prediction can be of great utility for landslide risk assessment and disaster reduction in mountainous regions worldwide.

关键词： Landslide runout prediction Drone survey Multi-source data collaboration DAN3D numerical modeling Jianshanying landslide Guizhou Province Geological hazards survey engineering

Boosting charge transfer via interface charge reconstruction between amorphous NiFe-LDH and crystalline NiCo_(2)O_(4)for efficient alkaline water/seawater oxidation

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Nano Research 2024年第6期17卷 4856-4863页

作者： Zhonghang xing Yi Zhao Yunhai Wang Xiaohe Liu Zhiqiang guo Qingyun Chen International Research Center for Renewable Energy and State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China China School of Geology and Environment Xi’an University of Science and TechnologyXi’an 710049China Changqing Engineering Design Co. Ltd.Xi’an 710018China

Electrocatalysts with optimal efficiency and durability for the oxygen evolution reaction(OER)are becoming increasingly important as the demand for alkaline water/seawater electrolysis technology ***,a novel rose-shaped NiFe-layered double hydroxide(LDH)/NiCo_(2)O_(4)composed of amorphous wrinkled NiFe-LDH and highly crystalline NiCo_(2)O_(4)was synthesized with rich *** unsaturated metal sites are generated due to significant charge reconstruction at the heterointerface between the crystalline and amorphous *** metal sites could trigger and provide more active *** density functional theory(DFT)reveals that a new charge transfer channel(Co-Fe)was formed at the heterointerface between NiFe-LDH as electron acceptor and NiCo_(2)O_(4)as electron *** new charge transfer channel boosts interfacial charge transfer and enhances catalytic *** NiFe-LDH/NiCo_(2)O_(4)/nickel foam(NF)drives current densities of 10 and 100 mA·cm−2 with overpotentials of 193 and 236 mV,*** composite electrode demonstrates a fast turnover frequency(0.0143 s−1)at 1.45 V ***(RHE=reversible hydrogen electrode),which is 5.5 times greater than pure NiCo_(2)O_(4),suggesting its superior intrinsic ***,NiFe-LDH/NiCo_(2)O_(4)/NF electrode exhibited negligible degradation after 150 h of uninterrupted running in alkaline seawater *** study introduces a method for preparing high-efficiency electrocatalysts utilized in alkaline water/seawater electrolysis.

关键词： NiFe-layered double hydroxide(LDH)/NiCo_(2)O_(4)/nickel foam(NF) heterogeneous interfaces charge reconstruction water/seawater electrolysis

Combined blasting for protection of gob-side roadway with thick and hard roof

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3165-3180页

作者： qiang Fu Jun Yang Yubing Gao Changjiang Li Hongxu Song Yuxuan Liu xing Wu State Key Laboratory for Tunnel Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China

The deformation control of surrounding rock in gobside roadway with thick and hard roof poses a significant challenge to the safety and efficiency of coal *** address this issue,a novel approach combining directional and non-directional blasting techniques,known as combined blasting,was *** study focuses on the experimental investigation of the proposed method in the 122108 working face in Caojiatan Coal Mine as the engineering *** initial phase of the study involves physical model experiments to reveal the underlying mechanisms of combined blasting for protecting gob-side roadway with thick and hard *** results demonstrate that this approach effectively accelerates the collapse of thick and hard roofs,enhances the fragmentation and expansion coefficient of gangue,facilitates the filling of the goaf with gangue,and provides support to the overlying strata,thus reducing the subsidence of the overlying strata above the ***,the method involves cutting the main roof into shorter beams to decrease the stress and disrupt stress transmission *** numerical simulations were conducted to corroborate the findings of the physical model experiments,thus validating the accuracy of the experimental ***,field engineering experiments were performed,affirming the efficacy of the combined blasting method in mitigating the deformation of surrounding rock and achieving the desired protection of the gob-side roadway.

关键词： Thick and hard roof Surrounding rock control Combined blasting Fragmentation and expansion support stress relief

Understanding the Impact of H_(2) Diffusion Energy on the Formation Efficiency of H_(2) on the Interstellar Dust Grain Surface

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Research in Astronomy and Astrophysics 2024年第9期24卷 190-198页

作者： Xiaoying guo Wasim Iqbal qiang Chang Xiao-Hu Li School of Physics and Optoeletronic Engineering Shandong University of TechnologyZibo 255000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesUrumqi 830011China

We use microscopic Monte Carlo simulation techniques to investigate the impact of H_(2)diffusion energy on the recombination efficiency of H_(2)on interstellar dust grain surfaces under diffuse and translucent cloud *** constructed five models representing different possible conditions encountered by adsorbed H and H_(2)on interstellar dust *** implemented adsorption sites with multiple binding energies for surface species;the Encounter-Desorption mechanism was also *** study focused on silicate surfaces in diffuse clouds and water ice surfaces in translucent *** results show that the recombination efficiency of H_(2)on dust surfaces decreases as H_(2)diffusion energy *** interesting finding of this work is that considering different binding sites for H and H_(2)gives rise to multiple steady phases,during which the recombination efficiency remains constant with a change in H_(2)diffusion energy.

关键词： astrochemistry atomic processes ISM:molecules

Therapeutic Role of Chinese Medicine Targeting Nrf2/HO-1 Signaling Pathway in Myocardial Ischemia/Reperfusion Injury

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Chinese Journal of Integrative Medicine 2024年第10期30卷 949-960页

作者： LIU Chang-xing guo Xin-yi ZHOU Ya-bin WANG He First Clinical Medical School Heilongjiang University of Chinese MedicineHarbin150040China Clinical Medical School Chengdu University of Traditional Chinese MedicineChengdu610036China Department of Cardiology the First Affiliated Hospital of Heilongjiang University of Chinese MedicineHarbin150040China

Acute myocardial infarction(AMI),characterized by high incidence and mortality rates,poses a significant public health *** therapy,though the preferred treatment for AMI,often exacerbates cardiac damage,leading to myocardial ischemia/reperfusion injury(MI/RI).Consequently,the development of strategies to reduce MI/RI is an urgent priority in cardiovascular *** medicine,recognized for its multi-component,multi-pathway,and multi-target capabilities,provides a novel approach for alleviating MI/RI.A key area of interest is the nuclear factor E2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)*** pathway is instrumental in regulating inflammatory responses,oxidative stress,apoptosis,endoplasmic reticulum stress,and ferroptosis in MI/*** paper presents a comprehensive overview of the Nrf2/HO-1 signaling pathway's structure and its influence on MI/***,it reviews the latest research on leveraging Chinese medicine to modulate the Nrf2/HO-1 pathway in MI/RI treatment.

关键词： nuclear factor E2-related factor 2/heme oxygenase-1 signaling pathway myocardial ischemia/reperfusion injury Chinese medicine mechanisms

Distribution and bioavailability of mercury in size-fractioned atmospheric particles around an ultra-low emission power plant in Southwest China

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Journal of Environmental Sciences 2024年第4期138卷 141-152页

作者： Wei Zhang Jinjuan Li Hao Qiu xingqiang guo Zhijun Fei Yi xing Deliang Yin College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou Institute of TechnologyGuiyang 550003China Key Laboratory of Karst Georesources and Environment(Guizhou University) Ministry of EducationGuiyang 550025China School of Energy and Environmental Engineering University of Science&Technology BeijingBeijing 100083China

Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned particulate matter(PM)around the ULE-retrofitted CF-PPs are less ***,total Hg and its chemical speciation in TSP(total suspended particles),PM_(10)(aerodynamic particle diameter≤10μm)and PM_(2.5)(aerodynamic particle diameter≤2.5μm)around a ULE-retrofitted CFPP in Guizhou Province were *** PM_(2.5)concentration was higher around this ULE-retrofitted CFPP than that in the intra-regional urban cities,and it had higher mass Hg concentration than other sizefractioned *** Hg concentrations in PM had multifarious sources including CFPP,vehicle exhaust and biomass combustion,while they were significantly higher in autumn and winter than those in other seasons(P40%).Mass concentrations of exchangeable,HCl-soluble,elemental,and residual Hg in PM_(2.5)were higher than those in other size-fractioned PM,and were markedly elevated in autumn and winter(P<0.05).In PM_(2.5),HCl-soluble Hg presented a significantly positive relationship with elemental Hg(P<0.05),while residual Hg showed the significantly positive relationships with HCl-soluble Hg and elemental Hg(P<0.01).Overall,these results suggested that atmospheric PM-bound Hg around the ULE-retrofitted CFPP tends to accumulate in finer PM,and has higher bioavailable fractions,while has potential transformation between chemical speciation.

关键词： Size-fractioned particles Mercury Chemical speciation Coal-fired power plant Ultra-low emission