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Journal of Hydrodynamics 2023年第1期35卷 46-60页

作者： Xiao-bo quan Shao-hua Cheng College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China China Academy of Launch Vehicle Technology Beijing100076China Beijing Institute of Astronautical Systems Engineering Beijing100076China

The objective of this paper is mainly to investigate the ventilated tail cavity flow of an underwater vehicle with focus on the gas leakage regime by experimental and numerical methods.A high-speed camera and pressure measurement system are used to record the cavity flow patterns and pressure behavior,*** numerical simulation is carried out with volume of fluid(VOF)model and Filter-based turbulence model(FBM).Good agreement can be obtained between the experimental and numerical *** are three gas leakage types in the evolution of the intact tail cavity,i.e.,twin-vortex tube entrainment(TVTE),toroidal vortex shedding(TVS)and hybrid twin-vortex tube entrainment and toroidal vortex shedding(TVTE-TVS).With the increase of Fr,the unsteady behavior of the cavity with different gas leakage types becomes more *** internal flow characteristics revealed three distinct regions including the ventilation influence region,the reverse flow region and the high shear flow region and have an important effect on the transition of gas leakage regime.

关键词： Ventilated tail cavity gas leakage regime unsteady behavior internal flow characteristics

Emerging energy chemistry in lithium-sulfur pouch cells

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Science China Chemistry 2021年第3期64卷 337-338页

作者： bo-quan Li Qiang Zhang Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

On pursuing high-energy-density energy storage systems beyond the current lithium-ion battery technique, lithium-sulfur(Li-S) batteries have attracted worldwide attention due to their ultrahigh theoretical energy density up to 500 Wh kg-1[1]. The unique Li-S chemistry based on the conversion reactions between solid sulfur, dissolved lithium polysulfides, and solid lithium sulfide affords thermodynamic advantages including high cathode specific capacity and low anode potential [2].

关键词： battery lithium energy

Advanced electrosynthesis of hydrogen peroxide on oxidized carbon electrocatalyst

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Journal of Energy Chemistry 2019年第7期28卷 10-11页

作者： Chang-Xin Zhao bo-quan Li Qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University

Hydrogen peroxide(H2O2)is one of the 100 most important chemicals involved in multiple chemical processes including paper and textile manufacturing,waste degradation,and pharmaceutical production[1].Compared with the current industrial process to produce H2O2 following the anthraquinone oxidation/reduction method,electrochemical reduction of oxygen to H2O2 through a two-electron pathway constitutes an environmental friendly alternative route[2-4].Unfortunately,the electrogeneration of H2O2 from two-electron reduction of oxygen feedstock is kinetically sluggish and therefore requires electrocatalysts with high reactivity,high selectivity,and good stability[5,6].

关键词： Hydrogen peroxide electrosynthesis Oxygen reduction reaction Carbon nanotubes Electrocatalysis Oxygen functional groups

Natural killer/T-cell lymphoma with concomitant syndrome of inappropriate antidiuretic hormone secretion: A case report and review of literature

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World Journal of Clinical Cases 2018年第13期6卷 694-702页

作者： quan-bo Liu Rui Zheng Department of Respiratory Medicine Shengjing Hospital of China Medical University

We report a case of natural killer(NK)/T-cell lymphoma with concomitant syndrome of inappropriate antidiuretic hormone secretion(SIADH).The patient was a 64-yearold woman with a history of nasopharyngeal carcinoma of over 30 *** was admitted with a chief complaint of intermittent fever for 2 *** after admission indicated a swollen lymph node below the left *** imaging examinations on admission indicated multiple enlarged lymph nodes throughout the *** performed a left submandibular lymph node biopsy,and the results revealed NK/T-cell lymphoma.A biochemical examination indicated Epstein-Barr virus *** the same time,the patient developed *** on her laboratory examination and clinical manifestation,decreased plasma osmolality,urine osmolality greater than plasma osmolality,lack of skin swelling,normal blood pressure,normal renal function,no adrenal function detected on serology,and no abnormalities in imaging examination of the adrenal glands,the likelihood of SIADH in the patient was *** fluid restriction and administration of sodium chloride,the patient’s blood sodium level gradually ***,the immune function of the patient declined,there were severe symptoms of infection,and she died of respiratory ***/T-cell lymphoma associated with SIADH has not,to our knowledge,been previously reported in *** case emphasizes the importance of monitoring serum ion levels,especially serum sodium,in patients with NK/T-cell lymphoma.

关键词： Epstein-Barr virus Case report Literature review Syndrome of inappropriate antidiuretic hormone secretion Natural killer/T-cell lymphoma

Modelling and numerical simulation of isothermal oxidation of an individual magnetite pellet based on computational fluid dynamics

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Journal of Iron and Steel Research International 2021年第7期28卷 799-808页

作者： Zhou Pu Feng Zhou Yue Sun Ming Zhang bo-quan Li Department of Instrumentation Science and Technology Jiangsu UniversityZhenjiang 212013JiangsuChina

A mathematical model based on the computational fluid dynamics method,heat and mass transfer in porous media and the unreacted shrinking core model for the oxidation reaction of an individual magnetite pellet during preheating was *** commercial software COMSOL Multiphysics was used to simulate the change in the oxidation degree of the pellet at different temperatures and oxygen concentrations,and the simulated results were compared with the exper-imental *** model considered the influence of the exothermic heat of the reaction,and the enthalpy change was added to calculate the heat released by the *** results show that the oxidation rate on the surface of the pellet is much faster than that of the inside of the *** and oxygen concentration have great influence on the pellet oxidation ***,the exothermic calculation results show that there is a non-isothermal phenomenon inside the pellet,which leads to an increase in temperature inside the single *** the preheating condition of 873-1273 K(20%oxygen content),the heat released by the pellet oxidation reaction in a chain grate is 7.8×10^(6)-10.8×10^(6) kJ/h,which is very large and needs to be considered in the magnetite pellet oxidation modelling.

关键词： Magnetite pellet Oxidation Numerical simulation Unreacted shrinking core model Computational fluid dynamics

SCKF-STF-CN:a universal nonlinear filter for maneuver target tracking

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第8期12卷 678-686页

作者： quan-bo GE Wen-bin LI Cheng-lin WEN Institute of Information and Control Hangzhou Dianzi University Hangzhou 310018 China State Key Lab of lndustrial Control Technology Zhejiang University Hangzhou 310027 China

Square-root cubature Kalman filter (SCKF) is more effective for nonlinear state estimation than an unscented Kalman *** this paper,we study the design of nonlinear filters based on SCKF for the system with one step noise correlation and abrupt state ***,we give the SCKF that deals with the one step correlation between process and measurement noises,SCKF-CN in ***,we introduce the idea of a strong tracking filter to construct the adaptive square-root factor of the prediction error covariance with a fading factor,which makes SCKF-CN obtain outstanding tracking performance to the system with target maneuver or abrupt state ***,the tracking performance of SCKF is greatly improved.A universal nonlinear estimator is proposed,which can not only deal with the conventional nonlinear filter problem with high dimensionality and correlated noises,but also achieve an excellent strong tracking performance towards the abrupt change of target *** simulation examples with a bearings-only tracking system are illustrated to verify the efficiency of the proposed algorithms.

关键词： Nonlinear system Maneuver target tracking Correlated noises Square-root cubature Kalman filter (SCKF) Strong tracking filtering (STF)

A perspective on the electrocatalytic conversion of carbon dioxide to methanol with metallomacrocyclic catalysts

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Journal of Energy Chemistry 2022年第1期31卷 263-275,I0008页

作者： Xinyan Liu bo-quan Li Bing Ni Lei Wang Hong-Jie Peng Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Physical Chemistry Department of ChemistryUniversity of KonstanzUniversitatsstrasse 10D-78457 KonstanzGermany Department of Chemical and Biomolecular Engineering National University of Singapore.Singapore 117585Singapore

Electrocatalytic carb on dioxide reducti on(CO_(2)R)presents a promising route to establish zero-e mission carb on cycle and store in termittent ren ewable energy into chemical fuels for steady energy *** is an ideal energy carrier as alternative fuels and one of the most important commodity ***,methanol is currently mainly produced from fossil-based syngas,the production of which yields tremendous carb on emission *** CO_(2)R towards metha nol poses great potential to shift the paradigm of methanol *** this perspective,we focus our discussions on producing methanol from electrochemical CO_(2)R,using metallomacrocyclic molecules as the model *** discuss the motivation of having methanol as the sole CO_(2)R product,the documented application of metallomacrocyclic catalysts for CO_(2)R,and recent advance in catalyzing CO_(2) to methanol with cobalt phthalocyanine-based *** attempt to understand the key factors in determining the activity,selectivity,and stability of electrocatalytic CO_(2)-to-methanol conversion,and to draw mechanistic insights from existing ***,we identify the challenges hindering methanol electrosynthesis directly from CO_(2) and some intriguing directions worthy of further investigation and exploration.

关键词： Carbon dioxide reduction Methanol Electrocatalysis Molecular catalysts Single atom catalysts Heterogenization

Cooling and wetting of soil decelerated ground freezingethawing processes of the active layer in Xing'an permafrost regions in Northeast China

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Advances in Climate Change Research 2023年第1期14卷 126-135页

作者： bo-quan LU Shu-Ying ZANG Li-quan SONG Li SUN Miao LI Di BING Heilongjiang Province Key Laboratory of Geographical Environment Monitoring and Spatial Information Service in Cold Regions Harbin Normal UniversityHarbin 150025China Heilongjiang Province Collaborative Innovation Center of Cold Region Ecological Safety Harbin 150025China

The accelerated or decelerated freezingethawing processes of the active layer in Xing'an permafrost regions are crucial for the protection of *** better understand the freezingethawing processes of the active layer and its driving factors,according to the observation from 2017 to 2020 of soil temperature and water content in the active layer of forest and peatland in two representative hemiboreal ecosystems in the Da Xing'anling Mountains,Northeast China,the study explored in detail the effects of climatic conditions and local factors on the hydrothermal and freezingethawing processes of active layer *** results showed that during the freezingethawing cycles of 2017-2020,freezing and thawing start times in the peatland and forest ecosystems soils were generally delayed,and it took longer for the active layer soil to completely thaw than to *** annual average soil temperature in the peatland's active layer(5-80 cm)was 0.7-2.0℃ lower than that in the forest,and the annual average soil moisture content on the peatland was 5.5%-26.7%higher than that in the *** with the forest ecosystem soils,the ground surface freezing time of the peatland was delayed by 3e10 d,and the freezing rate decreased by 1.1-1.5 cm d1,while the beginning time of thawing was advanced by 22-27 d,and the thawing rate decreased by 1.3-1.4 cm d^(-1).In the process of decreasing soil temperature and increasing soil moisture content,the freezing and thawing rate of the active layer would be reduced,decelerating the freezingethawing processes of the active layer in the process of decreasing soil temperature and increasing soil moisture *** results provide the key original data for studying the formation and evolution of active layer and permafrost in the Xing'an permafrost regions in Northeast China and can be used to validate the prediction of ecosystem succession under the combined influences of climate change and permafrost degradation.

关键词： Freezingethawing processes Hydrothermal dynamics Active layer Hemiboreal ecosystems Xing'an permafrost

Modeling tail bubble dynamics during the launch of an underwater vehicle using the boundary element method

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Journal of Hydrodynamics 2022年第3期34卷 434-443页

作者： Shao-hua Cheng Xiao-bo quan Sai Zhang Tian-yuan Zhang Shuai Li College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China Beijing Institute of Astronautical Systems Engineering Beijing100076China China Academy of Launch Vehicle Technology Beijing100076China

A tail bubble is generated behind a high-speed vehicle at the early stage of the underwater launch *** tail bubble dynamic behavior involves expansion,overexpansion,contraction,pinch-off and jet formation,and it significantly influences the vehicle’s ***,the tail bubble dynamic behavior is an issue not very well *** paper establishes a numerical model for the interaction between the tail bubble and the vehicle based on the boundary element method(BEM)to gain new insight into this *** BEM results are compared to a computational fluid dynamics model to validate the numerical model,and good agreement is ***,a convergence test of the BEM model is conducted to verify its independence of the mesh *** influence of some governing parameters on the evolution of the tail bubble is then systematically studied,focusing on its maximum radius,pinch-off time,and pinch-off *** are two pinch-off position regimes of the tail bubble,one at the bottom and the other near the middle.

关键词： Underwater launch tail bubble bubble dynamics boundary element method

Hydrogen Peroxide in Plants:a Versatile Molecule of the Reactive Oxygen Species Network

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Journal of Integrative Plant Biology 2008年第1期50卷 2-18页

作者： Li-Juan quan bo Zhang Wei-Wei Shi Hong-Yu Li MOE Key Laboratory of Arid and Grassland Ecology School of Life Sciences Lanzhou University Lanzhou 730000 China

Plants often face the challenge of severe environmental conditions, which include various biotic and abiotic stresses that exert adverse effects on plant growth and development. During evolution, plants have evolved complex regulatory mechanisms to adapt to various environmental stressors. One of the consequences of stress is an increase in the cellular concentration of reactive oxygen species （ROS）, which are subsequently converted to hydrogen peroxide （H2O2）. Even under normal conditions, higher plants produce ROS during metabolic processes. Excess concentrations of ROS result in oxidative damage to or the apoptotic death of cells. Development of an antioxidant defense system in plants protects them against oxidative stress damage. These ROS and, more particularly, H2O2, play versatile roles in normal plant physiological processes and in resistance to stresses. Recently, H2O2 has been regarded as a signaling molecule and regulator of the expression of some genes in cells. This review describes various aspects of H2O2 function, generation and scavenging, gene regulation and cross-links with other physiological molecules during plant growth, development and resistance responses.

关键词： antioxidant system gene regulation hydrogen peroxide (H2O2) reactive oxygen species (ROS) signaling molecule.