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Scale effects of the continental coastline of China

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Journal of Geographical Sciences 2011年第6期21卷 1101-1111页

作者： su Fenzhen GAO yi zhou Chenghu YANG Xiaomei FEI Xianyun LREIS Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Yantai Institute of Coastal Zone Research CAS Yantai 264003 Shandong China Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Geodesy ＆ Geomatics Engineering Huaihai Institute of Technology Lianyungang 222005Jiangsu China Jiangsu Marine Resources Development Research Institute Lianyungang 222005 Jiangsu China

Spatial scale is a fundamental problem in Geography. Scale effect caused by fractal characteristic of coastline becomes a common focus of coastal zone managers and researchers. In this study, based on DEM and remote sensing images, multi-scale continental coastlines of China were extracted and the fractal characteristic was analyzed. The results are shown as follows. （1） The continental coastline of China fits the fractal model, and the fractal dimension is 1.195. （2） The scale significant differences according to uplift effects with fractal dimensions of coastline have and subsidence segments along the continental coastlines of China. （3） The fractal dimension of coastline has significant spatial heterogeneity according to the coastline types. The fractal dimension of sandy coastline located in Luanhe River plain is 1.109. The dimension of muddy coastline located in northern Jiangsu Plain is 1.059, while that of rocky coastline along southeastern Fujian is 1.293. （4） The length of rocky coastline is affected by scale more than that of muddy and sandy coastline. Since coastline is the conjunction of sea, land and air surface, the study of coastline scale effect is one of the scientific bases for the researches on air-sea-land interaction in multi-scales.

关键词： scale effect fractal dimension coastline uplift segment subsidence segment coastline type

Red Emission of Eu（lll） Complex Based on 1-（7-（ferf-butyl）-g-ethyl-gH- carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione Excited by Blue Light

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Chinese Journal of Chemical Physics 2012年第6期25卷 697-702,I0004页

作者： Sheng-gui Liu Wen-yi su Rong-kai Pan Xiao-ping zhou School of Chemistry Science and Technology Zhanjiang Normal University Zhanjiang 524048 China

A new Eu（III） complex, EuL3（phen）, was synthesized, where L is the abbreviation of de- protonated 1-（7-（tert-butyl）-9-ethyl-gH-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione （HL）, phen is the abbreviation of 1,10-phenanthroline. The Eu（III） complex was characterized by element analysis, IR, 1H NMR, UV-visible absorption spectroscopy, thermogravimetric anal- ysis （TGA）, and photoluminescence measurements （PL）. TGA shows that thermal stability of the complex is up to 325 ~C. PL measurement indicates that the Eu（III） complex exhibits intense red-emission and extends their excitation bands to visible region. LEDs device was successfully fabricated by precoating complex EuL3 （phen） onto 460 nm blue-emitting InGaN chip. The emission of device shows that the complex can act as red phosphor in combination with 460 nm blue-emitting chips. This europium complex based on 1-（7-（tert-butyl）-9- ethyl-9H-carbazol-2-yl）-4,4,4-trifluorobutane-l,3-dione is a kind of interesting red-emitting material excited by blue light, which could avoid the damage of excitation by UV light.

关键词： Carbazole fl-diketone Lanthanide complex Chemical synthesis Luminescence

Spin-dependent transport properties and Seebeck effects for a crossed graphene superlattice p-n junction with armchair edge

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Frontiers of physics 2018年第4期13卷 145-157页

作者： Ben-Hu zhou Ben-Liang zhou Yang-su Zeng Man-yi Duan Guang-Hui zhou Department of Physics Shaoyang University Shaoyang 422001 China Department of Physics and Key Laboratory for Low-Dimensional Structures and Quantum Manipulation (Ministry of Education) Hunan Normal University Changsha 410081 China College of Physics and Electronic Engineering Sichuan Normal University Chengdu 610068 China

Using the nonequilibrium Green＇s function method combined with the tight-binding Hamiltonian, we theoretically investigate the spin-dependent transmission probability and spin Seebeck coefficient of a crossed armchair-edge graphene nanoribbon （AGNR） superl＇attice p-n junction under a perpendicular magnetic field with a ferromagnetic insulator, where junction widths Wi of 40 and 41 are considered to exemplify the effect of semiconducting and metallic AGNRs, respectively. A pristine AGNR system is metallic when the transverse layer m = 3j ＋ 2 with a positive integer j and an insulator otherwise. When stubs are present, a semiconducting AGNR junction with width W1= 40 always shows metallic behavior regardless of the potential drop magnitude, magnetization strength, stub length, and per- pendicular magnetic field strength. However, metallic or semiconducting behavior can be obtained from a metallic AGNR junction with Wi = 41 by adjusting these physical parameters. Furthermore, a metal-to-semiconductor transition can be obtained for both superlattice p-n junctions by adjust- ing the number of periods of the superlattice. In addition, the spin-dependent Seebeck coefficient and spin Seebeck coefficient of the two systems are of the same order of magnitude owing to the appearance of a transmission gap, and the maximum absolute value of the spin Seebeck coefficient reaches 370 μV/K when the optimized parameters are used. The calculated results offer new possi- bilities for designing electronic or heat-spintronic nanodevices based on the graphene superlattice p-n junction.

关键词： crossed graphene superlattice p-n junction spin-dependent transport properties Seebeck coefficient nonequilibrium Green's function

Technological advances in cancer immunity:from immunogenomics to single-cell analysis and artificial intelligence

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Signal Transduction and Targeted Therapy 2021年第9期6卷 2674-2696页

作者： ying Xu Guan-Hua su Ding Ma yi Xiao Zhi-Ming Shao yi-zhou Jiang Key Laboratory of Breast Cancer in Shanghai Department of Breast SurgeryFudan University Shanghai Cancer CenterShanghaiChina Department of Oncology Shanghai Medical CollegeFudan UniversityShanghaiChina Institutes of Biomedical Sciences Fudan UniversityShanghaiChina

Immunotherapies play critical roles in cancer ***,given that only a few patients respond to immune checkpoint blockades and other immunotherapeutic strategies,more novel technologies are needed to decipher the complicated interplay between tumor cells and the components of the tumor immune microenvironment(TIME).Tumor immunomics refers to the integrated study of the TIME using immunogenomics,immunoproteomics,immune-bioinformatics,and other multi-omics data reflecting the immune states of tumors,which has relied on the rapid development of next-generation ***-throughput genomic and transcriptomic data may be utilized for calculating the abundance of immune ceils and predicting tumor antigens,referring to ***,as bulk sequencing represents the average characteristics of a heterogeneous cell population,it fails to distinguish distinct cell ***-cell-based technologies enable better dissection of the TIME through precise immune cell subpopulation and spatial architecture *** addition,radiomics and digital pathology-based deep learning models largely contribute to research on cancer *** artificial intelligence technologies have performed well in predicting response to immunotherapy,with profound significance in cancer *** this review,we briefly summarize conventional and state-of-the-art technologies in the field of immunogenomics,single-cell and artificial intelligence,and present prospects for future research.

关键词： immuno immunity artificial

PDCA循环法对外科辅助用药合理应用的效果分析

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中国处方药 2020年第4期18卷 46-48页

作者：吴红杨辉苏贻洲刘艳金泰宇张茜王莉朱加粉连云港市第二人民医院药学部江苏连云港222000

目的探讨PDCA循环法促进外科辅助用药合理应用的效果。方法运用PDCA循环法,分别抽取2018年10~12月外科出院病历300份为干预前组,2019年1~3月和2019年4~6月外科出院病历各300份为干预后组。比较干预前后辅助用药使用率、科室辅助用药使... 详细信息

目的探讨PDCA循环法促进外科辅助用药合理应用的效果。方法运用PDCA循环法,分别抽取2018年10~12月外科出院病历300份为干预前组,2019年1~3月和2019年4~6月外科出院病历各300份为干预后组。比较干预前后辅助用药使用率、科室辅助用药使用金额占比及辅助用药合理使用率,并对外科辅助用药的使用存在问题进行分析。结果实施2轮PDCA循环管理干预后,外科辅助用药使用率由47.33%(干预前)降至39.00%(第2轮干预后),差异有统计学意义(P=0.039)。且用药合理率明显提高,由54.33%(干预前)提高至74.67%(第2轮干预后),差异有统计学意义(P=0.000)。结论 PDCA循环管理模式在规范外科辅助用药合理应用中持续改进的效果显著。

关键词： PDCA循环管理外科辅助用药合理用药临床药师

Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 135-145页

作者： su Shuo Long Jun Duan Qinghua zhou Han Zhao yi SINOPEC Research Institute of Petroleum Processing Co.Ltd. Beijing 100083

To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established *** molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular *** results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen *** on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur *** results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions.

关键词： lubricating oil antioxidant molecular mechanism molecular design antioxidant performance

Study on Load Bearing Characteristics of Novel Expandable Deepwater Drilling Conductor Based on Laboratory Experiment and Field Test

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China Ocean Engineering 2023年第1期37卷 16-28页

作者： ZHANG Ming-he YANG Jin YANG Yu-xiang XU Dong-sheng zhou yi-su College of Safety and Ocean Engineering China University of Petroleum-BeijingBeijing 102249China

A novel expandable conductor was designed and applied in deep-water drilling to improve the vertical and lateral bearing capacity with a significant reduction of conductor jetting depth and soaking time. The vertical and lateral bearing capability of expandable conductors was depicted based on the ultimate subgrade reaction method and pile foundation bearing theory. The load-bearing characteristics of a laboratory-scale expandable conductor were analyzed through laboratory experiments. The serial simulation experiments are accomplished to study the bearing characteristics(vertical ultimate bearing capacity, lateral soil pressure, and lateral displacement) during the conductor soaking process. The laboratory experimental results show that the larger the length and thickness of expandable materials are,the higher the bearing capacity of the wellhead will be. During the conductor soaking process, the soil pressure around the three expandable conductors increases faster, strings representing a stronger squeezing effect and resulting in higher vertical bearing capacity. Furthermore, the lateral displacement of novel expandable conductor is smaller than that of the conventional conductor. All the advantages mentioned above contributed to the reduction of conductor’s jetting depth and soaking time. Lastly, the application workflow of a novel expandable deep-water drilling conductor was established and the autonomous expandable conductor was successfully applied in the South China Sea with a significant reduction of conductor’s jetting depth and soaking time. According to the soil properties and designed installation depth of the surface conductor, the arrangement of expandable materials should be designed reasonably to meet the safety condition and reduce the construction cost of the subsea wellhead.

关键词： novel expandable surface conductor deep water subsea wellhead laboratory experiment field test

Observability Analysis and Navigation Algorithm for Distributed Satellites System Using Relative Range Measurements

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Journal of Systems Science & Complexity 2018年第5期31卷 1206-1226页

作者： su Qiya HUANG yi Beijing Institute of Remote Sensing Equipment Beijing 100854 China Key Laboratory of Systems and Control Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China School of Mathematical Sciences University of Chinese Academy of Sciences Beijing 100049 China

The problem of navigation for the distributed satellites system using relative range mea- surements is investigated. Firstly, observability for every participating satellites is analyzed based on the nonlinear Keplerian model containing J2 perturbation and the nonlinear measurements. It is proven that the minimum number of tracking satellites to assure the observability of the distributed satellites system is three. Additionally, the analysis shows that the J2 perturbation and the nonlinearity make little contribution to improve the observability for the navigation. Then, a quasi-consistent extended Kalman filter based navigation algorithm is proposed, which is quasi-consistent and can provide an on- line evaluation of the navigation precision. The simulation illustrates the feasibility and effectiveness of the proposed navigation algorithm for the distributed satellites system.

关键词： Distributed satellites system (DSS) navigation observability quasi-consistent extendedKalman filter (QCEKF) relative range.

Two-stage Optimal Dispatching of AC/DC Hybrid Active Distribution Systems Considering Network Flexibility

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 52-65页

作者： yi su Jiashen Teh School of Electrical and Electronic Engineering Universiti Sains Malaysia(USM)14300 Nibong TebalPenangMalaysia IEEE

The increasing flexibility of active distribution systems(ADSs)coupled with the high penetration of renewable distributed generators(RDGs)leads to the increase of the *** is of practical significance to achieve the largest amount of RDG penetration in ADSs and maintain the optimal *** study establishes an alternating current(AC)/direct current(DC)hybrid ADS model that considers the dynamic thermal rating,soft open point,and distribution network reconfiguration(DNR).Moreover,it transforms the optimal dispatching into a second-order cone programming *** the different control time scales of dispatchable resources,the following two-stage dispatching framework is proposed.d dispatch uses hourly input data with the goal(1)The day-ahea of minimizing the grid loss and RDG *** obtains the optimal 24-hour schedule to determine the dispatching plans for DNR and the energy storage system.(2)The intraday dispatch uses 15-min input data for 1-hour rolling-plan dispatch but only executes the first 15 min of *** eliminate error between the actual operation and dispatching plan,the first 15 min is divided into three 5-min step-by-step *** goal of each step is to trace the tie-line power of the intraday rolling-plan dispatch to the greatest extent at the minimum *** measured data are used as feedback input for the rolling-plan dispatch after each step is executed.A case study shows that the comprehensive cooperative ADS model can release the line capacity,reduce losses,and improve the penetration rate of ***,the two-stage dispatching framework can handle source-load fluctuations and enhance system stability.

关键词： Two-stage dispatching network flexibility renewable distributed generator second-order cone programming(SOCP) alternating current(AC)/direct current(DC)hybrid active distribution system