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Petroleum Science 2024年第2期21卷 1369-1384页

作者： chong-zheng sun Yu-Xing Li Hui Han Xiao-Yi Geng Xiao Lu College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266590ShandongChina College of Pipeline and Civil Engineering/Shandong Provincial Key Laboratory of Oil&Gas Storage and Transportation Safety China University of PetroleumQingdao 266580ShandongChina

Liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat exchanger structure and hydrogen liquefaction process(LH2). The methods of cryogenic visualization experiment, theoretical analysis and numerical simulation are conducted to study the falling film flow characteristics with the effect of co-current gas flow in LH2spiral wound heat *** results show that the flow rate of mixed refrigerant has a great influence on liquid film spreading process, falling film flow pattern and heat transfer performance. The liquid film of LH2mixed refrigerant with column flow pattern can not uniformly and completely cover the tube wall surface. As liquid flow rate increases, the falling film flow pattern evolves into sheet-column flow and sheet flow, and liquid film completely covers the surface of tube wall. With the increase of shear effect of gas-phase mixed refrigerant in the same direction, the liquid film gradually becomes unstable, and the flow pattern eventually evolves into a mist flow.

关键词： Hydrogen liquefaction Spiral wound heat exchanger Flow pattern transition Falling film flow

Research on the falling film flow and heat transfer characteristics of FLNG spiral wound heat exchanger under sea conditions

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Petroleum Science 2022年第3期19卷 1276-1290页

作者： chong-zheng sun Liang Liu Yu-Xing Li Jian-Lu Zhu College of Pipeline and Civil Engineering/Shandong Provincial Key Laboratory of Oil&Gas Storage and Transportation Safety/Qingdao Key Laboratory of Circle Sea Oil&Gas Storage and Transportation Technology China University of PetroleumQingdaoShandong266580China

As the key equipment of floating liquefied natural gas(FLNG)process,the performance of spiral wound heat exchanger(SWHE)influences operation costs and reliability of the whole *** sea conditions destroy the falling film flow state of the refrigeration and then affect the heat transfer performance of FLNG *** order to design and optimize the SWHE,a cryogenic experimental device of FLNG process and a numerical model of falling film flow have been constructed to study the effects of sea conditions on the falling film flow and heat transfer characteristics of *** cryogenic experimental results show that the pitching conditions have larger effects on the heat transfer performance than *** the pitching angle of 7°,the natural gas temperature and gaseous refrigerant temperature increase by 3.22°C and 7.42°C,*** flow rates of refrigerant and feed natural gas have a great impact on the heat transfer performance of SWHE under pitching and compound sloshing *** the tilt angle increases to 9°,the tube structure with outer diameter D=8 mm and pipe spacing S=4 mm is recommended to reduce the drying area of the pipe wall surface.

关键词： FLNG Spiral wound heat exchanger Falling film flow Cryogenic heat transfer Sea condition

Spatial distribution of shallow landslides caused by Typhoon Lekima in 2019 in Zhejiang Province, China

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Journal of Mountain Science 2024年第5期21卷 1564-1580页

作者： CUI Yulong YANG Liu XU chong zheng Jun School of Civil Engineering and Architecture Anhui University of Science and TechnologyHuainan 232001China National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Department of Civil Engineering Zhejiang UniversityHangzhou 310058China

In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous terrain of this area, combined with rapid rainfall accumulation, has led to a surge in flash floods and severe geological hazards. On August 10, 2019, Typhoon Lekima made landfall in Zhejiang Province, China, and its torrential rainfall triggered extensive landslides, resulting in substantial damage and economic losses. Utilizing high-resolution satellite images, we compiled a landslide inventory of the affected area, which comprises a total of 2,774 rainfallinduced landslides over an area of 2965 km2. The majority of these landslides were small to mediumsized and exhibited elongated, clustered patterns. Some landslides displayed characteristics of high-level initiation, obstructing or partially blocking rivers, leading to the formation of debris dams. We used the inventory to analyze the distribution pattern of the landslides and their relationship with topographical, geological, and hydrological factors. The results showed that landslide abundance was closely related to elevation, slope angle, faults, and road density. The landslides were predominantly located in hilly and low mountainous areas, with elevations ranging from 150 to 300 m, slopes of 20 to 30 degrees, and a NE-SE aspect. Notably, we observed the highest Landslide Number Density(LND) and Landslide Area Percentage(LAP) in the rhyolite region. Landslides were concentrated within approximately 4 km on either side of fault zones, with their size and frequency negatively correlated with distances to faults, roads, and river systems. Furthermore, under the influence of typhoons, regions with denser vegetation cover exhibited higher landslide density, reaching maximum values in shrubland areas. In areas experiencing significantly increased concentrated rainfall, landslide density also showed a corr

关键词： Typhoon rainfall Landslide characteristics Spatial distribution Southeast coastal region

Observer-Based Adaptive Robust Precision Motion Control of a Multi-Joint Hydraulic Manipulator

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1213-1226页

作者： zheng Chen Shizhao Zhou chong Shen Litong Lyu Junhui Zhang Bin Yao State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027 Ocean College Zhejiang UniversityZhoushan 316021China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050000 State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Mechanical Engineering Purdue UniversityWest LafayetteIN 47907 USA

Hydraulic manipulators are usually applied in heavy-load and harsh operation ***,when faced with a complex operation,the traditional proportional-integral-derivative(PID)control may not meet requirements for high control ***-based full-state-feedback control is an effective alternative,but the states of a hydraulic manipulator are not always available and reliable in practical applications,particularly the joint angular velocity *** that it is not suitable to obtain the velocity signal directly from differentiating of position measurement,the low-pass filtering is commonly used,but it will definitely restrict the closed-loop bandwidth of the whole *** avoid this problem and realize better control performance,this paper proposes a novel observerbased adaptive robust controller(obARC)for a multi-joint hydraulic manipulator subjected to both parametric uncertainties and the lack of accurate velocity ***,a nonlinear adaptive observer is first designed to handle the lack of velocity measurement with the consideration of parametric ***,the adaptive robust control is developed to compensate for the dynamic uncertainties,and the close-loop system robust stability is theoretically proved under the observation and control ***,comparative experiments are carried out to show that the designed controller can achieve a performance improvement over the traditional methods,specifically yielding better control accuracy owing to the closed-loop bandwidth breakthrough,which is limited by low-pass filtering in fullstate-feedback control.

关键词： handle Observer filtering

Multi-Strategy Assisted Multi-Objective Whale Optimization Algorithm for Feature Selection

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1563-1593页

作者： Deng Yang chong Zhou Xuemeng Wei Zhikun Chen zheng Zhang School of Information Engineering Hebei GEO UniversityShijiazhuang050031China Faculty of Science University of AlbertaEdmontonT2N1N4Canada College of Resources and Environment Beibu Gulf UniversityQinzhou535011China Clinical Laboratory The Frist Hospital of Hebei Medical UniversityShijiazhuang050000China

In classification problems,datasets often contain a large amount of features,but not all of them are relevant for accurate *** fact,irrelevant features may even hinder classification *** selection aims to alleviate this issue by minimizing the number of features in the subset while simultaneously minimizing the classification error ***-objective optimization approaches employ an evaluation function designed as an aggregate function with a parameter,but the results obtained depend on the value of the *** eliminate this parameter’s influence,the problem can be reformulated as a multi-objective optimization *** Whale Optimization Algorithm(WOA)is widely used in optimization problems because of its simplicity and easy *** this paper,we propose a multi-strategy assisted multi-objective WOA(MSMOWOA)to address feature *** enhance the algorithm’s search ability,we integrate multiple strategies such as Levy flight,Grey Wolf Optimizer,and adaptive mutation into ***,we utilize an external repository to store non-dominant solution sets and grid technology is used to maintain *** on fourteen University of California Irvine(UCI)datasets demonstrate that our proposed method effectively removes redundant features and improves classification *** source code can be accessed from the website:https://***/zc0315/MSMOWOA.

关键词： Multi-objective optimization whale optimization algorithm multi-strategy feature selection

Preoperative prognostic nutritional index predicts long-term outcomes of patients with ampullary adenocarcinoma after curative pancreatoduodenectomy

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1291-1300页

作者： chong-Yuan sun Xiao-Jie Zhang zheng Li He Fei Ze-Feng Li Dong-Bing Zhao Department of Pancreatic and Gastric Surgical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

BACKGROUND The prognostic nutritional index(PNI),a marker of immune-nutrition balance,has predictive value for the survival and prognosis of patients with various *** To explore the clinical significance of the preoperative PNI on the prognosis of ampullary adenocarcinoma(AC)patients who underwent curative *** The data concerning 233 patients diagnosed with ACs were extracted and analyzed at our institution from January 1998 to December *** patients were categorized into low and high PNI groups based on the cutoff value determined by receiver operating characteristic curve *** compared disease-free survival(DFS)and overall survival(OS)between these groups and assessed prognostic factors through univariate and multivariate *** The optimal cutoff value for the PNI was established at *** with a PNI≥45.3 were categorized into the PNI-high group,while those with a PNI<45.3 were assigned to the PNI-low *** within the PNI-low group tended to be of advanced age and exhibited higher levels of aspartate transaminase and total bilirubin and a lower creatinine level than were those in the PNI-high *** 5-year OS rates for patients with a PNI≥45.3 and a PNI<45.3 were 61.8%and 43.4%,respectively,while the 5-year DFS rates were 53.5%and 38.3%,*** in the PNI-low group had shorter OS(P=0.006)and DFS(P=0.012).In addition,multivariate analysis revealed that the PNI,pathological T stage and pathological N stage were found to be independent prognostic factors for both OS and *** The PNI is a straightforward and valuable marker for predicting long-term survival after *** PNI should be incorporated into the standard assessment of patients with AC.

关键词： Ampullary carcinoma Prognostic nutritional index Prognosis Pancreaticoduodenectomy

Transfer film effects induced by 3D-printed polyether-ether-ketone with excellent tribological properties for joint prosthesis

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Bio-Design and Manufacturing 2024年第1期7卷 43-56页

作者： Yang Li Jibao zheng Changning sun Dichen Li State Key Laboratory for Manufacturing System Engineering School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710054China National Medical Products Administration(NMPA)Key Laboratory for Research and Evaluation of Additive Manufacturing Medical Devices Xi’an Jiaotong UniversityXi’an 710054China

Based on the building principle of additive manufacturing,printing orientation mainly determines the tribological properties of joint *** this study,we created a polyether-ether-ketone(PEEK)joint prosthesis using fused filament fabrication and investigated the effects of printing orientation on its tribological properties using a pin-on-plate tribometer in 25% newborn calf *** ultrahigh molecular weight polyethylene transfer film is formed on the surface of PEEK due to the mechanical capture of wear debris by the 3D-printed groove morphology,which is significantly impacted by the printing orientation of *** the printing orientation was parallel to the sliding direction of friction,the number and size of the transfer film increased due to higher steady *** transfer film protected the matrix and reduced the friction coefficient and wear rate of friction pairs by 39.13%and 74.33%,***,our findings provide a novel perspective regarding the role of printing orientation in designing knee prostheses,facilitating its practical applications.

关键词： 3D printing orientation Transfer film Tribological properties Polyether-ether-ketone Knee prosthesis

On-surface synthesis and characterization of polyynic carbon chains

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National Science Review 2024年第3期11卷 192-199页

作者： Wenze Gao Wei zheng Luye sun Faming Kang zheng Zhou Wei Xu Interdisciplinary Materials Research Center School of Materials Science and Engineering Tongji University

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.

关键词： polyyne scanning probe microscopy carbon allotrope on-surface synthesis organometallic polyyne

Advances of machine learning in materials science: Ideas and techniques

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Frontiers of physics 2024年第1期19卷 155-194页

作者： Sue Sin chong Yi Sheng Ng Hui-Qiong Wang Jin-Cheng zheng Department of New Energy Science and Engineering Xiamen University MalaysiaSepang 43900Malaysia Engineering Research Center of Micro-nano Optoelectronic Materials and Devices Ministry of EducationFujian Key Laboratory of Semiconductor Materials and ApplicationsCI Center for OSEDand Department of PhysicsXiamen UniversityXiamen 361005China

In this big data era, the use of large dataset in conjunction with machine learning (ML) has been increasingly popular in both industry and academia. In recent times, the field of materials science is also undergoing a big data revolution, with large database and repositories appearing everywhere. Traditionally, materials science is a trial-and-error field, in both the computational and experimental departments. With the advent of machine learning-based techniques, there has been a paradigm shift: materials can now be screened quickly using ML models and even generated based on materials with similar properties;ML has also quietly infiltrated many sub-disciplinary under materials science. However, ML remains relatively new to the field and is expanding its wing quickly. There are a plethora of readily-available big data architectures and abundance of ML models and software;The call to integrate all these elements in a comprehensive research procedure is becoming an important direction of material science research. In this review, we attempt to provide an introduction and reference of ML to materials scientists, covering as much as possible the commonly used methods and applications, and discussing the future possibilities.

关键词： machine learning materials science

Targeted drug approvals in 2023:breakthroughs by the FDA and NMPA

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Signal Transduction and Targeted Therapy 2024年第3期9卷 813-821页

作者： Lang zheng Wenjing Wang Qiu sun Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China West China Medical Publishers West China HospitalSichuan UniversityChengdu 610041China

According to the official website of China’s National Medicines and Pharmaceutical Administration(NMPA),a total of 87 novel drugs were approved in China in 2023,with targeted drugs accounting for 67.8%of the total,amounting to 59 drugs(Fig.1a;Table 1)[https://***/yaopin/ypjgdt/***].Notably,domestic innovation is flourishing,with five first-in-class drugs,including Glumetinib,a c-Met inhibitor from Haihe Biopharma;Leritrelvir,a 3CL protease inhibitor from Raynovent;Anaprazole,a proton pump inhibitor from Xuanzhu Biopharm;Pegol-Sihematide,an EPO drug from Hansoh Pharma;and Zuberitamab from BioRay Biopharmaceutical Co.,***,the world’s first allosteric inhibitor targeting TYK2,Sotyktu(deucravacitinib),has been approved for the treatment of psoriasis and Selumetinib,a MEK inhibitor co-developed by AstraZeneca and Merck Sharp&Dohme(MSD),became the first approved drug in China for the treatment of neurofibromatosis type I(NF1).Beyond these drugs,the approval of novel drug types such as CAR-T cell products,siRNA,monoclonal antibodies,dual antibodies,and ADCs in China is a significant development in the country’s pharmaceutical industry(Fig.1a).

关键词： drugs Merck approval