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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： xiao-qi Jia shuai-kang zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental validation.The experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly analyzed.The cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation formed.The formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of cavitation.In addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid change.This phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Ammonia storage and slip under steady and transient state in close-coupled SCR

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Journal of Environmental Sciences 2024年第4期138卷 470-481页

作者： Shiyu Liu Zhaohuan zhang Zexian Guo Boyuan Wang Buyu Wang xiao Ma Shijin shuai State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Institute for Aero Engine Tsinghua UniversityBeijing 100084China

The close-coupled selective catalytic reduction(cc-SCR)catalyst is an effective technology to reduce tailpipe NOx emission during cold start.This paper investigated the optimal ammonia storage under steady and transient state in the cc-SCR.The study showed that a trade-off between NOx conversion efficiency and ammonia slip is observed on the pareto solutions under steady state,and the optimal ammonia storage is calculated with ammonia slip less than 10μL/L based on the ChinaⅥemission legislation.The rapid temperature increase will lead to severe ammonia slip in the transient test cycle.A simplified 0-D calculation method on ammonia slip under transient state is proposed based on kinetic model of ammonia adsorption and desorption.In addition,the effect of ammonia storage,catalyst temperature and temperature increasing rate on ammonia slip are analyzed.The optimal ammonia storage is calculated with maximum ammonia slip less than 100μL/L according to the oxidation efficiency of ammonia slip catalyst(ASC)downstream cc-SCR.It was found that the optimal ammonia storage under transient state is much lower than that under steady state in cc-SCR at lower temperature,and a phase diagram is established to analyze the influence of temperature and temperature increasing rate on optimal ammonia storage.

关键词： Close-coupled SCR Ammonia storage and slip Steady and transient state Generic algorithm

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Gradient inflammation in the pancreatic stump after pancreaticoduodenectomy:Two case reports and review of literature

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World Journal of Clinical Cases 2024年第9期12卷 1649-1659页

作者： Tie-Gong Wang Liang Tian xiao-Ling zhang Lei zhang Xiu-Lei Zhao De-shuai Kong Department of Surgery Cangzhou Central HospitalCangzhou 061000Hebei ProvinceChina Department of Pathology Cangzhou Central HospitalCangzhou 061000Hebei ProvinceChina

BACKGROUND Postoperative pancreatic fistula(POPF)contributes significantly to morbidity and mortality after pancreaticoduodenectomy(PD).However,the underlying mechanisms remain unclear.This study explored this pathology in the pancreatic stumps and elucidated the mechanisms of POPF following PD.CASE SUMMARY Pathological analysis and 16S rRNA gene sequencing were performed on specimens obtained from two patients who underwent complete pancreatectomy for grade C POPF after PD.Gradient inflammation is present in the pancreatic stump.The apoptosis was lower than that in the normal pancreas.Moreover,neu-trophildominated inflammatory cells are concentrated in the ductal system.No-tably,neutrophils migrated through the ductal wall in acinar duct metaplasia-formed ducts.Additionally,evidence indicates that gut microbes migrate from the digestive tract.Gradient inflammation occurs in pancreatic stumps after PD.CONCLUSION The mechanisms underlying POPF include high biochemical activity in the pancreas,mechanical injury,and digestive reflux.To prevent POPF and address pancreatic inflammation and reflux,breaking the link with anastomotic dehi-scence is practical.

关键词： Pancreaticoduodenectomy Postoperative pancreatic fistula Inflammation Digestive reflux Case report

Review on Security Defense Technology Research in Edge Computing Environment

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Chinese Journal of Electronics 2024年第1期33卷 1-18页

作者： Ke SHANG Weizhen HE shuai zhang National Digital Switching System Engineering and Technological R&D Center

Edge computing, which achieves quick data processing by sinking data computing and storage to the network edge, has grown rapidly along with the Internet of things. The new network architecture of edge computing brings new security challenges. Based on this, this paper investigates the edge computing security literature published in recent years and summarizes and analyzes research work on edge computing security from different attack surfaces. We start with the definition and architecture of edge computing. From the attack surface between device and edge server, as well as on edge servers, the research describes the security threats and defense methods of edge computing. In addition, the cause of the attack and the pros and cons of defense methods is introduced. The challenges and future research directions of edge computing are given.

关键词： Edge computing Security Threat Defense Architecture Attack surface

Interface Engineering of Titanium Nitride Nanotube Composites for Excellent Microwave Absorption at Elevated Temperature

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Nano-Micro Letters 2024年第9期16卷 147-160页

作者： Cuiping Li Dan Li shuai zhang Long Ma Lei zhang* Jingwei zhang Chunhong Gong College of Chemistry and Molecular Sciences Henan UniversityKaifeng 475004People’s Republic of China National and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004People’s Republic of China

Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently,the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority.Herein,due to the high melting point,good electrical conductivity,excellent environmental stability,EM coupling effect,and abundant interfaces of titanium nitride(TiN)nanotubes,they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process.Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane(PDMS),enhanced polarization loss relaxations were created,which could not only improve the depletion efficiency of EMWA,but also contribute to the optimized impedance matching at elevated temperature.Therefore,the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature(298-573 K),while achieved an effective absorption bandwidth(EAB)value of 3.23 GHz and a minimum reflection loss(RLmin)value of−44.15 dB at 423 K.This study not only clarifies the relationship between dielectric loss capacity(conduction loss and polarization loss)and temperature,but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering.

关键词： TiN nanotubes Interface engineering Polarization loss Impedance matching Electromagnetic wave absorption performance

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Urgent one-stage endoscopic treatment for choledocholithiasis related moderate to severe acute cholangitis: A propensity scorematched analysis

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World Journal of Gastroenterology 2024年第15期30卷 2118-2127页

作者： Yang Zhou Yin-Qiu zhang shuai-Jing Huang Yan Liang xiao Liang Masoom Wali Ya-Dong Feng Department of Gastroenterology Zhongda HospitalSchool of MedicineSoutheast UniversityNanjing 210009Jiangsu ProvinceChina Department of Gastroenterology BenQ Medical CenterThe Affiliated BenQ Hospital of Nanjing Medical UniversityNanjing 210019Jiangsu ProvinceChina

BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasis are unclear.AIM To investigate the safety and feasibility of one-stage endoscopic treatment for moderate to severe AC.METHODS We enrolled all patients diagnosed with moderate to severe cholangitis due to common bile duct stones from January 2019 to July 2023.The outcomes were compared in this study between patients who underwent ERCP within 24 h and those who underwent ERCP 24 h later,employing a propensity score(PS)frame-work.Our primary outcomes were intensive care unit(ICU)admission rates,ICU length of stay,and duration of antibiotic use.RESULTS In total,we included 254 patients and categorized them into two groups based on the time elapsed between admission and intervention:The urgent group(≤24 h,n=102)and the elective group(>24 h,n=152).Ninety-three pairs of patients with similar characteristics were selected by PS matching.The urgent ERCP group had more ICU admissions(34.4%vs 21.5%,P=0.05),shorter ICU stays(3 d vs 9 d,P<0.001),fewer antibiotic use(6 d vs 9 d,P<0.001),and shorter hospital stays(9 d vs 18.5 d,P<0.001).There were no significant differences observed in adverse events,in-hospital mortality,recurrent cholangitis occurrence,30-d readmission rate or 30-d mortality.CONCLUSION Urgent one-stage ERCP provides the advantages of a shorter ICU stay,a shorter duration of antibiotic use,and a shorter hospital stay.

关键词： Acute cholangitis Endoscopic retrograde cholangiopancreatography One-stage treatment Optimal time

Associative cultural landscape approach to interpreting traditional ecological wisdom:A case of Inuit habitat

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Frontiers of Architectural Research 2024年第1期13卷 79-96页

作者： Peng zhang shuai Li Department of Landscape Architecture College of Architecture and Urban PlanningTongji UniversityShanghai 200092China

Global climate change and the accelerated melting of glaciers have raised concerns about the ability to manage ice-snow environments.Historically,human ancestors have mastered the ecological wisdom of working with ice-snow environments,but the phenomenon has not yet been articulated in cultural landscape methodologies that emphasize“nature-culture relevance”.The challenging living environment often compels indigenous people to form a strong bond with their surroundings,leading to the creation of long-term ecological wisdom through synergistic relationships with the environment.This ecological environment is conceptualized as a cognitive space in the form of the landscape,with which the aboriginal community norms and individual spirits continually interact.Such interactions generate numerous non-material cultural evidences,such as culture,art,religion,and other ideological aspects of the nation.These evidences symbolize the intellectual outcome of the relationship between humans and the landscape,and they create the“spiritual relevance”through personification and contextualization.The aim of the study is to explore the traditional ecological wisdom of the Inuit people who live in the harsh Arctic,and analyze the Inuit’s interaction with the landscape through the lens of“associative cultural landscape”,and decode the survival experience that the Inuit have accumulated through their long-term synergy with the Arctic environment.The findings focus on the synergy between the Inuit and the ice-snow landscape,examining the knowledge and ecological wisdom that the Inuit acquire from the ice-snow landscape.Our goal is to develop a perspective of the ecological environment from the viewpoint of aboriginal people and establish a methodology,model,and framework for“associative cultural landscape”that incorporates ethnic non-material cultural evidences.From the results,a total of nine models for interpreting traditional Inuit ecological wisdom are generated based on the“diamond model”of“associative cultural landscape”,coverin

关键词： Landscape architecture Associative cultural landscape Nature-culture relevance Cultural landscape Traditional ecological wisdom Non-material cultural evidence Methodology Habitat Living environment Ice-snow landscape

ALKBH5 suppresses autophagic flux via N6-methyladenosine demethylation of ZKSCAN3 mRNA in acute pancreatitis

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World Journal of Gastroenterology 2024年第12期30卷 1764-1776页

作者： Tao zhang shuai Zhu Geng-Wen Huang Department of General Surgery Xiangya HospitalCentral South UniversityChangsha 410005HunanChina. National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410005HunanChina.

BACKGROUND Increasing evidence has demonstrated that N6-methyladenosine(m6A)RNA modification plays an essential role in a wide range of pathological conditions.Impaired autophagy is a critical hallmark of acute pancreatitis(AP).AIM To explore the role of the m6A modification of ZKSCAN3 in the regulation of autophagy in AP.METHODS The AP mouse cell model was established by cerulein-treated mouse pancreatic acinar cells(MPC-83),and the results were confirmed by the levels of amylase and inflammatory factors.Autophagy activity was evaluated by specific identification of the autophagy-related microstructure and the expression of autophagy-related genes.ZKSCAN3 and ALKBH5 were knocked down to study the function in AP.A m6A RNA binding protein immunoprecipitation assay was used to study how the m6A modification of ZKSCAN3 mRNA is regulated by ALKBH.RESULTS The increased expression of amylase and inflammatory factors in the supernatant and the accumulation of autophagic vacuoles verified that the AP mouse cell model was established.The downregulation of LAMP2 and upregulation of LC3-II/I and SQSTM1 demonstrated that autophagy was impaired in AP.The expression of ZKSCAN3 was upregulated in AP.Inhibition of ZKSCAN3 increased the expression of LAMP2 and decreased the expression of the inflammatory factors,LC3-II/I and SQSTM1.Furthermore,ALKBH5 was upregulated in AP.Knockdown of ALKBH5 downregulated ZKSCAN3 expression and restored decreased autophagic flux in AP.Notably,the bioinformatic analysis revealed 23 potential m6A modification sites on ZKSCAN3 mRNA.The m6A modification of ZKSCAN3 mRNA was significantly decreased in AP.Knockdown of ALKBH5 increased the modification of ZKSCAN3 mRNA,which confirmed that ALKBH5 upregulated ZKSCAN3 expression in a m6A-dependent manner.CONCLUSION ALKBH5 inhibits autophagic flux through m6A demethylation of ZKSCAN3 mRNA in AP,thereby aggravating the severity of the disease.

关键词： Acute pancreatitis Autophagy ZKSCAN3 N6-methyladenosine ALKBH5

3D coarse-grained DPM simulation of the MIP reaction-regeneration loop

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Particuology 2024年第6期89卷 57-66页

作者： Yanhao Ye shuai zhang Ji Xu Wei Ge State Key Laboratory of Mesoscience and Engineering(formerly State Key Laboratory of Multiphase Complex Systems) Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)process.Although the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulate such a complex loop system due to limitations of coarse-grained(CG)models,computing software,and hardware.In this study,a newly proposed soft-shell CG-DPM model with a CG ratio of up to 800 is used to simulate a 3.5 Mt/a industrial-scale MIP reactor-regenerator loop.The solid fraction distribution obtained is found to agree well with in-situ measurements.Hydrodynamic properties including the distribution of solid fraction,gas and solid velocity,standard derivation of solid fraction with time,temporal distribution of the flow field,and particle residence time distribution are measured in the simulation,which are meaningful to better design and operate such systems in the future.

关键词： Discrete particle method Coarse-grain Maximizing iso-paraffins Full-loop Reaction-regeneration system

Anti-aging performance improvement and enhanced combustion efficiency of boron via the coating of PDA

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Defence Technology（防务技术） 2024年第3期33卷 399-410页

作者： shuai Ma Qinghai Shu Mengyang zhang Hongyu Huang Yansong Shi Xijuan Lv shuai Zhao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement(MOE) Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of TechnologyBeijing100081China Tangshan Research Institute of Beijing Institute of Technology Tangshan063000HebeiChina

Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during storage.The polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of boron.The results indicated that the PDA coating formed a fishing net structure on the surface of boron particles.The heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw boron.Specifically,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw boron.Simultaneously,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were evaluated.It was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,respectively.The peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@AP.Therefore,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites.

关键词： Boron particles Polydopamine Anti-aging performance improvement Heat release

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