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Energy budget of cold and hot gas-solid fluidized beds through CFD-deM simulations

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Particuology 2024年第6期89卷 153-171页

作者： Lei bi Yunpeng Jiao Chunjiang Liu Jianhua chen Wei Ge School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Direct energy budget is carried out for both cold and hot flow in gas–solid fluidization ***,the energy paths are proposed from thermodynamic *** consumption means total power input to the specific system,and it can be decomposed into energy retention and energy *** retention is the variation of accumulated mechanical energy in the system,and energy dissipation is the energy converted to heat by irreversible *** based on the Computational Fluid Dynamics-Discrete Element Method(CFD-deM)framework,different energy terms are quantified from the specific flow elements of fluid cells and particles as well as their interactions with the *** order to clarify the energy budget,it is important to identify which system is studied:the particle-fluid system or the particle *** the cold flow,the total energy consumption of the particle sub-system can well indicate the onset of bubbling and turbulent,while the variation of local energy consumption terms can reflect the evolution of heterogeneous *** the hot flow,different heat transfer mechanisms are analyzed and the solver is modified to reproduce the experimental *** impact of the heat transfer mechanisms and heat production on energy consumption is also *** proposed budget method has proven to be energy-conservative and easy to conduct,and it is hopeful to be applied to other multiphase flow systems.

关键词： Energy budget Gas-solid fluidization CFD-deM Regime transition Heat transfer mechanism

A novel domain decomposition-based model for efficient dynamic predictions of large composite machine tools

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Science China(Technological Sciences) 2024年第6期67卷 1765-1782页

作者： YU YangBo JI Yu Lei chen YanRen XU Kun bi QingZhen State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

We propose a large combined moving component composed of carbon fiber reinforced polymer(CFRP)laminates for making lightweight machine tools with high dynamic *** accurate dynamic prediction of composite machine tools is essential for the new generation machine *** paper aims to address two challenges in numerical dynamic modeling and the design of composite machine tools to enhance development efficiency.(1)Anisotropic composite laminates,which form the composite machine tool,exhibit coupling in various *** propose the generalized continuity condition of the boundary to tackle this dynamic modeling challenge.(2)Composite machine tools feature numerous composite-metal coupled *** mechanical model correction of isotropic metals is performed to address their *** take the example of a five-axis gantry machine tool with composite moving parts,establish a dynamic model for efficient prediction,and verify it through simulation and *** proposed method yields remarkable results,with an average relative error of only 3.85%in modal frequency prediction and a staggering 99.7%reduction in solution time compared to finite element *** further discuss the dynamic performance of the machine tool under varied stacking angles and layer numbers of the composite machine *** propose general design criteria for composite machine tools to consider the modal frequency and manufacturing cost of machine tools.

关键词： machine tool dynamics carbon fiber reinforced polymer composite laminates

Treatment patterns and survival outcomes in patients with nonmetastatic early-onset pancreatic cancer

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World Journal of Gastroenterology 2024年第12期30卷 1739-1750页

作者： Le-Tian Zhang Ying Zhang bi-Yang Cao chen-chen Wu Jing Wang Graduate School Chinese PLA Medical SchoolBeijing 100853China department of Radiation Oncology First Medical Center of Chinese PLA General HospitalBeijing 100853China department of Internal Medicine Hospital of University of Science and Technology BeijingBeijing 100083China department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

BACKGROUND The incidence of patients with early-onset pancreatic cancer(EOPC;age≤50 years at diagnosis)is on the rise,placing a heavy burden on individuals,families,and *** role of combination therapy including surgery,radiotherapy,and chemotherapy in non-metastatic EOPC is not *** To investigate the treatment patterns and survival outcomes in patients with non-metastatic *** A total of 277 patients with non-metastatic EOPC who were treated at our institution between 2017 and 2021 were investigated *** survival(OS),disease-free survival,and progression-free survival were estimated using the Kaplan-Meier *** and multivariate analyses with the Cox proportional hazards model were used to identify prognostic *** With a median follow-up time of 34.6 months,the 1-year,2-year,and 3-year OS rates for the entire cohort were 84.3%,51.5%,and 27.6%,*** median OS of patients with localized disease who received surgery alone and adjuvant therapy(AT)were 21.2 months and 28.8 months,respectively(P=0.007).The median OS of patients with locally advanced disease who received radiotherapy-based combination therapy(RCT),surgery after neoadjuvant therapy(NAT),and chemotherapy were 28.5 months,25.6 months,and 14.0 months,respectively(P=0.002).The median OS after regional recurrence were 16.0 months,13.4 months,and 8.9 months in the RCT,chemotherapy,and supportive therapy groups,respectively(P=0.035).Multivariate analysis demonstrated that carbohydrate antigen 19-9 level,pathological grade,T-stage,N-stage,and resection were independent prognostic factors for non-metastatic *** AT improves postoperative survival in localized *** after NAT and RCT are the preferred therapeutic options for patients with locally advanced EOPC.

关键词： Pancreatic cancer Early-onset Non-metastatic Multimodal treatment Radiotherapy Overall survival

Essential oils improve nursery pigs'performance and appetite via modulation of intestinal health and microbiota

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Animal Nutrition 2024年第1期16卷 174-188页

作者： bi-chen Zhao Tian-Hao Wang Jian chen Bai-Hao Qiu Ya-Ru Xu Jin-Long Li College of Veterinary Medicine Northeast Agricultural UniversityHarbin150030China Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine Northeast Agricultural UniversityHarbin150030China Key Laboratory of the Provincial Education department of Heilongjiang for Common Animal Disease Prevention and Treatment Northeast Agricultural UniversityHarbin150030China

Optimal intestinal health and functionality are essential for animal health and performance,and simultaneously intestinal nutrient transporters and intestinal peptides are also involved in appetite and feed intake control *** the potential of essential oil(EO)in improving animal performance and improving feed palatability,we hypothesized that dietary supplementation of cinnamaldehyde and carvacrol could improve performance and appetite of nursery pigs by modulating intestinal health and ***(100 mg/kg),carvacrol(100 mg/kg),and their mixtures(including 50 mg/kg cinnamaldehyde and 50 mg/kg carvacrol)were supplemented into the diets of 240 nursery pigs for 42 d,and data related to performance were ***,the influence of EO on intestinal health,appetite and gut microbiota and their correlations were *** supplementation increased(Pdecreased(Pbility and local *** terms of intestinal development and the mucus barrier,EO promoted intestinal development and increased(Pbiome and the abundance of beneficial bacteria,and there was a correlation between altered bacterial structure and appetite-related *** findings indicate that EO is effective in promoting growth performance and nutrient absorption as well as in regulating appetite by improving intestinal health and ba

关键词： Nursery pig Essential oil Intestinal health Appetite Microbiota

Nitrogen isotope stratigraphy of the Early Cambrian successions in the Tarim Basin:Spatial variability of nitrogen cycling and its implication for paleo-oceanic redox conditions

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Acta Geochimica 2024年第4期43卷 785-801页

作者： bi Zhu Xuefeng Li Lu Ge Yongquan chen Institute of Earth’s Critical Zone School of Earth Sciences and EngineeringHohai UniversityNanjing 210098China Research Institute of Exploration and development Tarim Oil Field CompanyPetroChinaKorlaChina

The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in *** isotopic signatures of ancient sediments have the potential to elucidate the evolutionary path of marine redox states and the biogeochemical nitrogen cycle within the water column of the Early Cambrian *** existing research on this topic has predominantly focused on South China,the exploration of other continental margins has been limited,leaving contradictory hypotheses *** this study,pairedδ^(15)N andδ^(13)C org analyses were performed on the Lower Cambrian successions from the Shiairike section(inner ramp)and Well Tadong 2(deep shelf/basin)in the northwestern and eastern Tarim Basin,*** data from the Shiairike section reveal a discernible shift in the operation of different nitrogen cycles for the black chert-shale unit,also referred to as the black rock series in Chinese literature,of the Yurtus Formation(Fortunian stage to lower Stage 3).Oscillatingδ^(15)N values for its lower part are suggestive of alternating anaerobic assimilation of NH 4+and denitrification/*** is likely attributed to a shallow,unstable chemocline consistent with the upwelling and incursion of deep,anoxic waters during a major *** contrast,aerobic nitrogen cycling,indicated by positiveδ^(15)N values of>2‰,dominated the upper part alongside a reduction in upwelling *** the other hand,theδ^(15)N signatures of Xishanbulake and Xidashan Formations of Well Tadong 2,which encompass a time interval from the Cambrian Fortunian Age to Age 4,are indicative of N_(2)fixation by diazotrophs as the major nitrogen *** two studied intervals,although not time-equivalent,exhibit separated states of nitrogen cycling at least during the deposition of the Yurtus black rock *** spatially different nitrogen cycling of the studied sections is compatible with a redox-stratified ocean dur

关键词： Nitrogen isotopes Early Cambrian Tarim Black rock series

Lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides

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Chinese Journal of Chemical Engineering 2024年第3期67卷 238-246页

作者： Yong-Yi Zeng Xin-Yi Xu Jin-Xuan Xie Wen-Li chen Lan Liu Xin-Jian Yin bi-Shuang chen School of Marine Sciences Sun Yat-Sen UniversityZhuhai 519080China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional ***,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its *** this study,an engineered strain Escherichia coli(***)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into *** potential of *** BL21(de3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process *** a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light *** selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) *** the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based ***,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production.

关键词： Alkane-based biodiesel Renewable biomass Co-overexpression Lipase Photodecarboxylase

Efficient and fair PPO-based integrated scheduling method for multiple tasks of SATech-01 satellite

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Chinese Journal of Aeronautics 2024年第2期37卷 417-430页

作者： Qi SHI Lu LI Ziruo FANG Xingzi bi Huaqiu LIU Xiaofeng ZHANG Wen chen Jinpei YU Shanghai Satellite Network Research Institute CO. LTDShanghai 201210China Innovation Academy for Microsatellites of Chinese Academy of Sciences Shanghai 201306China University of Chinese Academy of Sciences Beijing 100039China

SATech-01 is an experimental satellite for space science exploration and on-orbit demonstration of advanced *** satellite is equipped with 16 experimental payloads and supports multiple working modes to meet the observation requirements of various *** to the limitation of platform power supply and data storage systems,proposing reasonable mission planning schemes to improve scientific revenue of the payloads becomes a critical *** this article,we formulate the integrated task scheduling of SATech-01 as a multi-objective optimization problem and propose a novel Fair Integrated Scheduling with Proximal Policy Optimization(FIS-PPO)algorithm to solve *** use multiple decision heads to generate decisions for each task and design the action mask to ensure the schedule meeting the platform *** results show that FIS-PPO could push the capability of the platform to the limit and improve the overall observation efficiency by 31.5%compared to rule-based plans currently ***,fairness is considered in the reward design and our method achieves much better performance in terms of equal task *** of its low computational complexity,our task scheduling algorithm has the potential to be directly deployed on board for real-time task scheduling in future space projects.

关键词： Satellite observatories SATech-01 Multi-modes platform Scheduling algorithms Reinforcement learning Proximal Policy Optimization(PPO)

Efficient Dynamic Locomotion of Quadruped Robot via Adaptive Diagonal Gait

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Journal of bionic Engineering 2024年第1期21卷 126-136页

作者： Jian bi Teng chen Xuewen Rong Guoteng Zhang Guanglin Lu Jingxuan Cao Han Jiang Yibin Li The Center for Robotics School of Control Science and EngineeringShandong UniversityJi Nan 250000China

Quadruped animals in the nature realize high energy efficiency locomotion by automatically changing their gait at different *** by this character,an efficient adaptive diagonal gait locomotion controller is designed for quadruped robot.A unique gait planning method is proposed in this *** the speed of robot varies,the gait cycle time and the proportion of stance and swing phase of each leg are adjusted to form a variety of *** optimal joint torque is calculated by the controller combined with Virtual Model Control(VMC)and Whole-Body Control(WBC)to realize the desired *** gait and step frequency of the robot can automatically adapt to the change of *** experiments are done with a quadruped robot made by our laboratory to verify that the gait can change automatically from slow-trotting to flying-trot during the period when speed is from 0 to 4 m/*** ratio of swing phase is from less than 0.5 to more than 0.5 to realize the running motion with four feet off the *** have shown that the controller can indeed consume less energy when robot runs at a wide range of speeds comparing to the basic controller.

关键词： Quadruped robot Gait transition Adaptive gait Energy efficiency

Effect of crystal morphology of ultrahigh-nickel cathode materials on high temperature electrochemical stability of lithium ion batteries

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Journal of Energy Chemistry 2024年第1期88卷 327-335,I0008页

作者： bi Luo Hui Li Haoyu Qi Yun Liu Chuanbo Zheng Weitong Du Jiafeng Zhang Lai chen School of Metallurgy Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600JiangsuChina National Engineering Laboratory for High-Efficiency Recovery of Refractory Nonferrous Metals School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083HunanChina School of Materials Science and Engineering Beijing Key Laboratory of Environmental Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Higher nickel content endows Ni-rich cathode materials LiNi_(x)Co_yMn_(1-x-y)O_(2)(x>0.6)with higher specific capacity and high energy density,which is regarded as the most promising cathode materials for Li-ion ***,the deterioration of structural stability hinders its practical application,especially under harsh working conditions such as high-temperature *** these circumstances,it becomes particularly critical to clarify the impact of the crystal morphology on the structure and high-temperature performance as for the ultrahigh-nickel ***,we conducted a comprehensive comparison in terms of microstructure,high-temperature long-cycle phase evolution,and high-temperature electrochemical stability,revealing the differences and the working mechanisms among polycrystalline(PC),single-crystalline(SC)and Al doped SC ultrahigh-nickel *** results show that the PC sample suffers a severe irreversible phase transition along with the appearance of microcracks,resulting a serious decay of both average voltage and the energy *** the Al doped SC sample exhibits superior cycling stability with intact layered ***-situ XRD and intraparticle structural evolution characterization reveal that Al doping can significantly alleviate the irreversible phase transition,thus inhibiting microcracks generation and enabling enhanced ***,it exhibits excellent cycling performance in pouch-type full-cell with a high capacity retention of 91.8%after 500 cycles at 55℃.This work promotes the fundamental understanding on the correlation between the crystalline morphology and high-temperature electrochemical stability and provides a guide for optimization the Ni-rich cathode materials.

关键词： Single-crystalline Ultrahigh-nickel cathode High-temperature performance Phase evolution