检索结果-南通市图书馆

维普期刊数据库博看期刊

An analytical transient coal permeability model:Sorption non-equilibrium index-based swelling switch

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1175-1191页

作者： Xingxing liu Jishan liu Liang chen Jinchang sheng Huimin Wang College of Civil and Transportation Engineering Hohai UniversityNanjing210098China School of Engineering The University of Western Australia35 Stirling HighwayCrawleyWA6009Australia College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China

Long-term permeability experiments have indicated that sorption-induced swelling can switch from internal to bulk depending on the evolutive sorption ***,this sorption swelling switch mechanism has not been considered in current analytical permeability *** study introduces a normalized sorption non-equilibrium index(SNEI)to characterize the sorption status,quantify the dynamical variations of matrix swelling accumulation and internal swelling partition,and formulate the sorption swelling switch *** incorporation of this index into the extended total effective stress concept leads to an analytical transient coal permeability *** results show that the sorption swelling switch itself results in the permeability switch under stress-constrained conditions,while the confined bulk swelling suppresses the permeability recovery to the continuous reduction under displacement-constrained *** verifications show that current experimental observations correspond to the early stages of the transient process,and they could be extended to the whole process with these *** study demonstrates the importance of the sorption swelling switch in determining permeability evolution using simple boundary *** provides new insights into experimentally revealing the sorption swelling switch in the future,and underscores the requirement of a rigorous model for complex coupled processes in large-scale coal seams.

关键词： Coal permeability Sorption swelling switch Sorption non-equilibrium Boundary conditions

Hydrodynamics and OCM reaction performance in a bubbling fluidized bed reactor and a riser reactor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第3期86卷 188-204页

作者： Min Cai Shuangzhu Kong sheng chen Mengxi liu Chunxi Lu State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China China Special Equipment Inspection and Research Institute Beijing102249China

The reasonable reactor design is of great importance for increasing the C_(2) yield(C2H4 and C2H6)of the oxidative coupling of methane(OCM),and the OCM reactor should remove the heat released in reactions quickly and efficiently and minimize the consecutive reaction of ethylene to carbon *** fluidized bed reactor is characterized by excellent heat transfer,superior mass transport,and large handling capacity,while fewer studies focused on large-scale fluidized bed reactors for the OCM ***,large cold-model experiments and computational fluid dynamics simulations were conducted to investigate hydrodynamics and the OCM reaction performance in a large-scale bubbling fluidized bed(BFB)and a large-scale *** the BFB reactor,consecutive reactions of ethylene are acute because of the strong gas back-mixing,high solids holdup,and non-uniform solids *** the consecutive reactions of ethylene are negligible due to the plug flow structure and low solids holdup in the riser ***,both reactors can achieve isothermal operation for the OCM *** C_(2) selectivity of 45.4% and C_(2) yield of 21.1% are obtained in the riser reactor,increasing by 20.3% and 5.8% individually than that in the BFB *** study provides useful information and reference to the OCM reactor designandcommercialization.

关键词： Oxidative coupling of methane Bubbling fluidized bed reactor Riser reactor Hydrodynamics Isothermal operation

Accelerating H^(*)desorption of hollow Mo_(2)C nanoreactor via in-situ grown carbon dots for electrocatalytic hydrogen evolution

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第9期96卷 464-471页

作者： Mengmeng liu Yuanyuan Jiang Zhuwei Cao Lulu liu Hong chen sheng Ye School of Materials and Chemistry Anhui Agricultural UniversityHefei 230036AnhuiChina

Molybdenum carbide(Mo_(2)C)is a promising non-noble metal electrocatalyst with electronic structures similar to Pt for hydrogen evolution reaction(HER).However,strong H^(*)adsorption at the Mo sites hinders the improvement of HER ***,we synthesized monodisperse hollow Mo_(2)C nanoreactors,in which the carbon dots(CD)were in situ formed onto the surface of Mo_(2)C through carburization *** to finite element simulation and analysis,the CD@Mo_(2)C possesses better mesoscale diffusion properties than Mo_(2)C *** optimized CD@Mo_(2)C nanoreactor demonstrates superior HER performance in alkaline electrolyte with a low overpotential of 57 mV at 10 mA cm^(−2),which is better than most Mo_(2)C-based ***,CD@Mo_(2)C exhibits excellent electrochemical stability during 240 h,confirmed by operando Raman and X-ray diffraction(XRD).Density functional theory(DFT)calculations show that carbon dots cause the d-band center of CD@Mo_(2)C to shift away from Fermi level,promoting water dissociation and the desorption of H^(*).This study provides a reasonable strategy towards high-activity Mo-based HER eletrocatalysts by modulating the strength of Mo–H bonds.

关键词： Mo_(2)C nanoreactor Carbon dots H^(*)desorption Electrocatalytic hydrogen evolution

Stable hydrogen-bonded organic frameworks and their photo-and electro-responses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7675-7699页

作者： Ying Hou Xin-Song Huang sheng-Hao Gong chen liu Yangyang liu Tian-Fu liu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry and Biochemistry California State UniversityLos AngelesCalifornia 90032USA College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China

Hydrogen-bonded organic frameworks(HOFs)are a recent class of porous materials that have garnered considerable research interest owing to their distinctive *** can be constructed through judicious selection of H-bonding motifs,which are further enforced by other weak intermolecular interactions such asπ–πstacking,van der Waals forces,and framework *** advantage of these interactions,we can expand the functional field of HOFs by introducing active ***,researchers have made substantial advancements in using HOFs for chemical sensing,catalysis,proton conduction,biological applications,and *** low bonding energy of H-bonds allows for precise control over the concentration of ligands in solvents,forming diverse HOF *** varied structures offer significant advantages for producing HOFs with photo-responsive and electro-responsive ***,the presence of H-bonds in HOFs results in their inherent lower stability compared to metal-organic frameworks(MOFs)and covalent-organic frameworks(COFs)formed via coordination and covalent bonds,*** a result,the pursuit of stable and innovative HOF materials with novel functional sites remains an ongoing *** review provides an overview of recent research progress in the development of new strategies for stable HOF synthesis and applications of HOFs with stimuli-responsive *** first classified all synthetic methods reported to date and discussed the stable HOFs synthesized,as well as their unique properties and *** addition,we summarized the applications of HOFs utilizing their synergistic responses to external stimuli,including photo,electrical,pressure,and chemical *** systematically reviewed stable HOF synthesis and applications,which may lead to a deeper understanding of the structure–activity relationship for these materials and guide future HOF design.

关键词： stable hydrogen-bonded organic frameworks(HOFs) photo-response electro-response photoelectric synergistic response

Development of a prognostic scoring system for hepatic vena cava Budd-Chiari syndrome with hepatocellular carcinoma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 370-375页

作者： sheng-Yan liu Lu-Hao Li Zhao-chen liu Su-Xin Li Xiao-Wei Dang Department of Hepatopancreatobiliary Surgery the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Budd-Chiari Syndrome Diagnosis and Treatment Center of Henan Province Zhengzhou 450052China

Background:Hepatocellular carcinoma(HCC)is a serious complication of hepatic vena cava Budd-Chiari syndrome(HVC-BCS)that significantly reduces the survival time of *** study aimed to analyze the prognostic factors influencing the survival of HVC-BCS patients with HCC and to develop a prognostic scoring ***:The clinical and follow-up data of 64 HVC-BCS patients with HCC who received invasive treatment at the First Affiliated Hospital of Zhengzhou University between January 2015 and December 2019 were retrospectively ***-Meier curves and log-rank tests were used to analyze the survival curve of patients and the difference in prognoses between the *** and multivariate Cox regression analyses were performed to analyze the influence of biochemical,tumor,and etiological characteristics on the total survival time of patients,and a new prognostic scoring system was developed according to the regression coefficients of the independent predictors in the statistical *** prediction efficiency was evaluated using the time-dependent receiver operating characteristics curve and concordance ***:Multivariate analysis showed that serum albumin level7 cm(HR=8.623,95%CI:3.771-19.715,P<0.001),and inferior vena cava stenosis(HR=3.612,95%CI:1.646-7.928,P=0.001)were independent predictors of survival.A prognostic scoring system was developed according to the above-mentioned independent predictors,and patients were classified into grades A,B,C and *** differences in survival were found among the four ***:This study successfully developed a prognostic scoring system for HVC-BCS patients with HCC,which is helpful for clinical evaluation of patient prognosis.

关键词： Budd-Chiari syndrome Hepatocellular carcinoma Prognostic factors Inferior vena cava stenosis Prognostic scoring system

维普期刊数据库

Full sexual maturity-cycle exposure to environmentally relevant concentrations of 17β-estradiol decreases reproductive capacity of zebrafish

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第3期137卷 580-592页

作者： Yongkang Zhang Yuanjun Jiang Qian Sun Meng Li sheng chen Jingyu Liang Chunsheng liu College of Fisheries Huazhong Agricultural UniversityWuhan 430070China School of Environmental Studies China University of GeosciencesWuhan 430074China

17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in ***,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of E2 for the full sexual maturation cycle remain *** this study,zebrafish were treatment with 0,10 or100 ng/L E2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were *** results showed that treatment with E2 lead to increased number of feminization in *** females,E2 decreased cumulative amount of spawning and inhibited the maturation of *** males,E2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of *** adverse effects on sperm might be responsible for the reduced fertilization observed in *** addition,treatment with E2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in ***,these results suggested that treatment with environmentally relevant concentrations of E2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.

关键词： Environmental estrogen Zebrafish Fecundity Gonadal development Endocrine disruption

维普期刊数据库

Response characteristics of PWR primary circuit under SBLOCAs considering steam bypass discharging

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第6期35卷 189-201页

作者： Shuai Yang Xiang-Bin Li Yu-sheng liu Jia-Ning Xu De-chen Zhang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy Beijing 102206China Nuclear and Radiation Safety Center MEPBeijing 100084China

Small-break superposed station blackout(SBO)accidents are the basic design accidents of nuclear power *** the condition of a small break in the cold leg,SBO further increases the severity of the accident,and the steam bypass discharg-ing system(GCT)in the second circuit can play an important role in guaranteeing core *** explore the influence of the GCT on the thermal-hydraulic characteristics of the primary circuit,RELAP5 software was used to establish a numerical model based on a typical pressurized water reactor nuclear power *** different small breaks in the cold-leg super-posed SBO were selected,and the impact of the GCT operation on the transient response characteristics of the primary and secondary circuit systems was *** results show that the GCT plays an indispensable role in core heat removal during an accident;otherwise,core safety cannot be *** GCT was used in conjunction with the primary safety injection system during the placement *** the break diameter was greater than a certain critical value,the core cooling rate could not be guaranteed to be less than 100 K/h;however,the core remained in a safe state.

关键词： Steam bypass discharging Pressurized water reactor SBLOCA Numerical simulation

维普期刊数据库

Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

在线全文

学校读者我要写书评

暂无评论

Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He Si-yuan Feng Jian Zhang Hong-wu Tang Yang Xiao sheng chen Chun-sheng liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM

Analysis and Optimization of Transient Mode Switching Behavior for Power Split Hybrid Electric Vehicle with Clutch Collaboration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Automotive Innovation 2024年第1期7卷 150-165页

作者： Dehua Shi sheng liu Yujie Shen Shaohua Wang Chaochun Yuan Long chen Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013China Jiangsu Province Engineering Research Center of Electric Drive System and Intelligent Control for Alternative Vehicles Zhenjiang 212013China

The power split hybrid electric vehicle(HEV)adopts a power coupling configuration featuring dual planetary gearsets and multiple clutches,enabling diverse operational modes through clutch engagement and *** multi-clutch configuration usually involves the collaboration of two clutches during the transient mode switching process,thereby substantially elevating control *** study focuses on power split HEVs that integrate multi-clutch mechanisms and investigates how different clutch collaboration manners impact the characteristics of transient mode *** powertrain model for the power-split HEV is established utilizing matrix-based *** the formulation of clutch torque curves and clutch collaboration models,this research systematically explores the effects of clutch engagement timing and the duration of clutch slipping state on transient mode switching *** upon this analysis,an optimization problem for control parameters pertaining to the two collaborative clutches is *** simulated annealing algorithm is employed to optimize these control *** results demonstrate that the clutch collaboration manners have a great influence on the transient mode switching *** with the pre-calibrated benchmark and the optimal solution derived by the genetic algorithm,the maximal longitudinal jerk and clutch slipping work during the transient mode switching process is reduced obviously with the optimal control parameters derived by the simulated annealing *** study provides valuable insights for the dynamic coordinated control of the power-split HEVs featuring complex clutch collaboration mechanisms.

关键词： Power split hybrid electric vehicle Transient mode switching Clutch collaboration Simulated annealing Powertrain model