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Surface enhanced fluorescence of gold nanoparticles to acridine orange molecules

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Surface enhanced fluorescence of gold nanoparticles to acrid...

Recommendation Method for Contrastive Enhancement of Neighborhood Information

第十五届全国光散射学术会议

作者： Hairong Zheng,Liangmin Xu,Zhenglong Zhang,Jun Dong,Meicen Liu,Gaining Liu (College of Physics and information technology,Shaanxi Normal University,Xian 710062,china) Shutang Chen,Xiaoling Zhang (department of chemistry,school of science,beijing institute of technology,beijing 100081,china)

＜正＞Surfaces of silver and gold nanostructures including colloids and island films have been frequently used as primary substrates for SEF *** enhancement effect on the fluorescence intensity is observed experimentally when fluorophores are in close proximity to the metal *** with silver substrate,gold surface has many potential advantages in the fundamental study and application of *** example,it has a higher chemical stability and the surface chemistry of it is well understood,gold nanopartieles（NPs） are safe for the life bodies,which is very important for the application of SEF in bioscienee and life science.

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma school of Computer science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

丙烯酸-马来酸酐共聚物钠盐分散水相中硫酸钡的研究

维普期刊数据库评论

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山西大学学报(自然科学版) 2006年第3期29卷 301-304页

作者：李汉承张强刘书静张小军北京理工大学理学院化学系河北农业大学理学院化学系中化化工科学技术总院北京100081 保定071001 100083

利用红外光谱、扫描电镜、沉降试验、粒径分析、流变行为等研究了丙烯酸-马来酸酐共聚物钠盐对硫酸钡水相悬浮液分散性能的影响.实验结果表明,添加适量分散剂可使硫酸钡粒子在水相中得到均匀分散开.硫酸钡悬浮液的黏度随共聚物钠盐浓度... 详细信息

利用红外光谱、扫描电镜、沉降试验、粒径分析、流变行为等研究了丙烯酸-马来酸酐共聚物钠盐对硫酸钡水相悬浮液分散性能的影响.实验结果表明,添加适量分散剂可使硫酸钡粒子在水相中得到均匀分散开.硫酸钡悬浮液的黏度随共聚物钠盐浓度的增加而降低,当加入质量浓度为0.6%分散剂时,粘度值达到最低值,然后再加入分散剂时粘度反而略有上升,加分散前后硫酸钡悬浮液的D 60分别为5.232 0μm和4.344 3μm.

关键词：丙烯酸-马来酸酐共聚物钠盐硫酸钡分散性

Chaotic attitude and reorientation maneuver for completely liquid-filled spacecraft with flexible appendage

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Acta Mechanica Sinica 2009年第2期25卷 271-277页

作者： B. Yue department of Mechanics, school of science,beijing institute of technology, 100081 beijing, china department of Mechanics School of Science Beijing Institute of Technology Beijing China

The present paper investigates the chaotic attitude dynamics and reorientation maneuver for completely viscous liquid-filled spacecraft with flexible appendage. All of the equations of motion are derived by using Lagrangian mechanics and then transformed into a form consisting of an unperturbed part plus perturbed terms so that the system＇s nonlinear characteristics can be exploited in phase space. Emphases are laid on the chaotic attitude dynamics produced from certain sets of physical parameter values of the spacecraft when energy dissipation acts to derive the body from minor to major axis spin. Numerical solutions of these equations show that the attitude dynamics of liquid-filled flexible spacecraft possesses characteristics common to random, non- periodic solutions and chaos, and it is demonstrated that the desired reorientation maneuver is guaranteed by using a pair of thruster impulses. The control strategy for reorientation maneuver is designed and the numerical simulation results are presented for both the uncontrolled and controlled spins transition.

关键词： Nonlinear attitude dynamics Attitude reorientation maneuver Control strategyLiquid-filled spacecraft

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咖啡因的科学共识

中国食品学报 2024年第6期24卷 498-504页

作者：中国食品科学技术学会北京100048

咖啡因是一种常见于咖啡、茶叶和可可等植物中的天然活性成分,作为功能添加成分已在国际食品领域广泛应用多年,适量摄入有助于健康人群提高注意力,促进运动能力,缓解疲劳。国内外相关食品安全监管机构一致认为,咖啡因虽在日常饮食中的... 详细信息

咖啡因是一种常见于咖啡、茶叶和可可等植物中的天然活性成分,作为功能添加成分已在国际食品领域广泛应用多年,适量摄入有助于健康人群提高注意力,促进运动能力,缓解疲劳。国内外相关食品安全监管机构一致认为,咖啡因虽在日常饮食中的摄入是安全的,但需关注个体差异、摄入量以及频率。许多国家和地区已对咖啡因在食品中的应用制定了严格的应用限量和标识规定。为进一步提升大众对咖啡因的科学认知,消除对咖啡因的偏见,推动咖啡因在相关食品产业的合理应用,中国食品科学技术学会组织食品科学、公共卫生、食品安全与食品营养等领域专家与相关产业界代表,通过现场咨询、文献检索、专题研讨等形式和方法,经广泛讨论形成咖啡因的科学共识,以推动咖啡因在我国的规范使用。

关键词：咖啡因健康益处摄入量应用管理

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The effects of relative density of metal foams on the stresses and deformation of beam under bending

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Acta Mechanica Sinica 2007年第4期23卷 409-414页

作者： Aiyu Zhu Tianyou Fan department of Mathematics,school of science,beijing institute of technology,P.O.Box 327,beijing 100081,china department of Physics,school of science,beijing institute of technology,P.O.Box 327,beijing 100081,china department of Mathematics School of Science Beijing Institute of Technology Beijing China department of Physics School of Science Beijing Institute of Technology Beijing China

The exact analytic solution of the pure bending beam of metallic foams is given. The effects of relative density of the material on stresses and deformation are revealed with the Triantafillou and Gibson constitutive law （TG model） taken as the analysis basis. Several examples for individual foams are discussed, showing the importance of compressibility of the cellular materials. One of the objects of this study is to generalize Hill＇s solution for incompressible plasticity to the case of compressible plasticity, and a kinematics parameter is brought into the analysis so that the velocity field can be determined.

关键词： Metal foams - Relative density Compressible plasticity Constitutive law - TG model

Chinese expert consensus on refined diagnosis,treatment,and management of advanced primary liver cancer(2023 edition)

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On the fluorescence of C_60 at room temperature

肝脏研究（英文） 2024年第2期8卷 61-71页

作者： Xiufeng Liu Feng Xia Yue Chen Huichuan Sun Zhengqiang Yang Bo Chen Ming Zhao Xinyu Bi Tao Peng Aizier Ainiwaer Zhiwen Luo Fusheng Wang Yinying Lu National Clinical Research Center for Infectious Diseases Society of Hepatology,beijing Medical Association Translational Medicine Branch,china Association of Gerontology and Geriatrics department of Medical Oncology Bayi Hospital Affiliated to Nanjing Chinese Medical University NanjingJiangsuChina department of Hepatobiliary Surgery Southwest HospitalArmy Medical University ChongqingChina Senior department of Hepatology The Fifth Medical Center of PLA General HospitalBeijingChina department of Liver Surgery and Transplantation Liver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina department of Interventional Therapy National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina department of Minimally Invasive Interventional Therapy Liver Cancer Study and Service GroupSun Yat-sen University Cancer CenterGuangzhouGuangdongChina department of Hepatobiliary Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina department of Hepatobiliary Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanningGuangxiChina Senior department of Infectious Diseases The Fifth Medical Center of PLA General HospitalBeijingChina Comprehensive Liver Cancer Center The Fifth Medical Center of PLA General HospitalBeijingChina

Hepatocellular carcinoma(HCC),commonly known as primary liver cancer,is a major cause of malignant tumors and cancer-related deaths in china,accounting for approximately 85％of all cancer cases in the *** guidelines have been used to diagnose and treat liver ***,these guidelines provide a broad definition for classifying advanced liver cancer,with an emphasis on a singular approach,without considering treatment options for individual ***,it is necessary to establish a comprehensive and practical expert consensus,specifically for china,to enhance the diagnosis and treatment of HCC using the Delphi *** classification criteria were refined for Chinese patients with HCC,and the corresponding optimal treatment regimen recommendations were *** recommendations took into account various factors,including tumor characteristics,vascular tumor thrombus grade,distant metastasis,liver function status,portal hypertension,and the hepatitis B virus replication status of patients with primary HCC,along with treatment *** findings and rec-ommendations provide detailed,scientific,and reasonable individualized diagnosis and treatment strategies for clinicians.

关键词： Hepatocellular carcinoma (HCC) Targeted therapy Immunotherapy Refined diagnosis and treatment Expert consensus

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 95-99页

作者： ZHANG Fang & ZHANG XiaoLing department of chemistry, beijing institute of technology, beijing 100081, china department of chemistry Beijing Institute of Technology Beijing China

The fluorescence properties of C 60 in different organic solvents have been investigated at room temperature. Three fluorescence emission centers are discovered and ascribed to different aggregations of C 60 in solvent. A series of blue fluorescence peaks centered at 440 nm derive from C 60 nanoparticles; a distinctive yellow-green fluorescence band in 575 nm region arises from the aggregates of C 60 nanoparticles; a more informative salmon fluorescence band around 700 nm originates from C 60 microcrystals. And the distinct configurations of C 60 aggregations are closely associated with the characteristic interaction between C 60 and solvent molecules.

关键词： C 60 fluorescence TEM confocal fluorescence spectroscopy

Fracture characteristics of concrete subjected to impact loading

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science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 253-261页

作者： LIU HaiFeng1,2,LIU HaiYan3 & SONG WeiDong1 1 State Key Laboratory of Explosion science and technology,beijing institute of technology,beijing 100081,china 2 school of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,china 3 school of science,beijing institute of technology,beijing 100081,china State Key Laboratory of Explosion science and technology Beijing Institute of Technology Beijing China school of Civil and Hydraulic Engineering Ningxia University Yinchuan China school of science Beijing Institute of Technology Beijing China

This paper takes concrete as a four-phase composite made of the intact matrix and three mutually perpendicular groups of penny-shaped micro-cracks. The intact matrix is assumed to be elastic,homogeneous and isotropic,and the micro-cracks are penny-shaped. Combined with the failure mechanism of concrete subjected to impact loading,a dynamic constitutive model for concrete is developed based on Mori-Tanaka's average stress concept and Eshelby's equivalent inclusion theory. Experimental results show that concrete is rate-dependent. The model predictions are in good agreement with the experimental results. The model may be used to simulate the mechanical behavior of concrete under impact loadings.

关键词： concrete micromechanics impact loading constitutive model