检索结果-南通市图书馆

Study on the mechanism of color coordinate shift of LED package

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2017年第7期38卷 78-82页

作者： Yunyi Zhuang Yong Wang bobo yang Zhanguo Li Lei yang Jun Zou National Key Laboratory on High Power Semiconductor Lasers Changchun University of Science and TechnologyChangchun 130022 China Zhejiang Emitting Optoelectronic Technology Co. Ltd. Jiaxing 314100 China School of Science Institute of Technology Shanghai 201418 China

In the paper, the influences of the chip, silicone and phosphors on the color coordinate shift of LED were studied. In the process of LED baking, it was found that the effect of the chip and silicone on the color coordinate drift is less than 3% through the analysis of each influencing factor. But the influence of the phosphors is large and accounted for 11.11% of the overall impact factors. Therefore, it is important to select the better green phosphors in thermal stability for the LED package and it has a guiding significance to the color coordinate of LED distribution.

关键词： light-emitting diode（LED） phosphors spectra intensity shift

Development of optical-thermal coupled model for phosphor-converted LEDs

在线全文

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2019年第3期12卷 249-267页

作者： Xinglu QIAN Jun ZOU Mingming SHI bobo yang yang LI Ziming WANG Yiming LIU Zizhuan LIU Fei ZHENG School of Science Shanghai Institute of TechnologyShanghai 201418China Zhejiang Emitting Optoelectronic Technology Co Ltd.Zhejiang 314100China School of Material Science and Engineering Shanghai Institute of TechnologyShanghai 201418China

In this review, first, we discussed the effect of phosphor features on optical properties by the software simulation in detail. A combination of these parameters: phosphor material, phosphor particle size and particle distribution, phosphor layer concentration, phosphor layer thickness, geometry, and location of the phosphor layer, will result in the final optical performance of the phosphor layer. Secondly, we introduced how to improve light extraction efficiency with various proposed methods. Thirdly, we summarized the thermal models to predict the phosphor temperature and the junction temperature. To stabilize the optical performance of phosphor-converted light emitting diodes (PC-LEDs), much effort has been made to reduce the junction temperature of the LED chips. The phosphor temperature, a critical reliability concern for PC-LEDs, should be attracted academic interest. Finally, we summed up optical-thermal coupled model for phosphors and summarized future optical- thermal issues exploring the light quality for LEDs. We foresee that optical-thermal coupled model for PC-LEDs should be paid more attention in the future.

关键词： phosphor-converted light emitting diodes (PC-LEDs) optical-thermal coupled model software simulation

Optical and electrical properties of a spiral LED filament

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2018年第2期39卷 39-44页

作者： Liping Wang Jun Zou bobo yang Wenbo Li yang Li Mingming Shi Wei Zhu Canyun Zhang Fengchao Wang Yujie Lin School of Materials Science and Engineering Shanghai Institute of Technology Shanghai 201418 China School of Science Shanghai Institute of Technology Shanghai 201418 China Zhejiang Emitting Optoelectronic Technology Company Hangzhou 310000 China Shanghai Pn-stone Optoelectronics Co. Ltd. Shanghai 201108 China

This paper introduces a new type of spiral white light-emitting diodes（WLED） filament with high luminous efficiency and uniform optical performance. The optical and thermal properties of the flexible filament were investigated at different stretching heights, namely 0, 1, 2, and 3 cm. The results indicated that the filament showed the best optical characteristics at the stretching height of 2 cm, because of good heat dissipation. In addition, the radiation temperature of the filament was inversely proportional to the output luminous flux. The reliability of the filament at a stretching height of 2 cm was also evaluated after 1000 h of use. The result demonstrated that the luminous flux decay of the bulb was only 0.85%. The flexible spiral WLED filament exhibiting high luminous flux and good reliability could be adapted to promote industrial development in the near future.

关键词： white light-emitting diode spiral substrate flip chip stretching height

在线全文

学校读者我要写书评

暂无评论

植物补光用LED荧光粉研究进展

照明工程学报 2024年第2期35卷 39-53页

作者：王大伟黄景鑫李杨石明明邹军杨波波王媛媛罗世鹏刘文斌陈启上海应用技术大学材料科学与工程学院上海201418 上海应用技术大学理学院上海201418 西双版纳承启科技有限公司云南西双版纳666100

植物的生长需要适宜的光照环境,然而在自然条件下,植物生长面临阳光、温度、水分等诸多不可控问题。为解决传统农业种植中气温光照不稳定的问题,人们开始发展工厂种植,其中植物的工厂种植核心就是人工光源。近年来植物补光技术被越来越... 详细信息

植物的生长需要适宜的光照环境,然而在自然条件下,植物生长面临阳光、温度、水分等诸多不可控问题。为解决传统农业种植中气温光照不稳定的问题,人们开始发展工厂种植,其中植物的工厂种植核心就是人工光源。近年来植物补光技术被越来越广泛地应用,光照对植物生长的影响及人工补光技术的研究也越来越多。本文介绍了LED植物灯的发展历程、现代LED光源作为植物工厂人工光源的优势、LED植物补光灯发光原理、及部分文中所涉及的光学参数;并总结了Eu^(2+)、Eu^(3+)、Mn^(4+)、Cr^(3+)、多离子共掺杂等荧光粉在植物补光技术中的研究现状。最后对以上不同荧光粉在植物补光技术中的优缺点进行了分析,对LED荧光粉在植物补光领域的发展前景进行了展望,为相关科研人员或机构提供了一些有技术价值的参考。

关键词：荧光粉离子掺杂人工光源植物补光

Noteworthy impacts of COVID-19 pandemic on cancer screening:A systematic review

在线全文

学校读者我要写书评

暂无评论

Fundamental Research 2024年第3期4卷 484-494页

作者： Huilin Wang Min yang Wei Xiong Quan Wang bobo Zheng yang Bai Kaiyong Zou Jibin Li Jiansong Ren Wanqing Chen Jingbo Zhai Jiang Li Office for Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Comprehensive Intervention National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Gynecology Endocrine&Reproductive Center National Clinical Research Center for Obstetric&Gynecologic Diseases Department of Obstetrics and GynecologyPeking Union Medical College HospitalPeking Union Medical College/Chinese Academy of Medical SciencesBeijing 100005China Ambulatory Surgery Center of Xijing Hospital Fourth Military Medical UniversityXi'an 710068China Department of General Surgery Shaanxi Provincial People’s HospitalXi'an 710068China College of Clinical Medicine Capital Medical UniversityBeijing 100069China School of Public Health Tianjin University of Traditional Chinese MedicineTianjin 301617China

The sudden onset of the coronavirus disease 2019(COVID-19)in January 2020 has affected essential global health services.Cancer-screening services that can reduce cancer mortality are strongly affected.However,the specific role of COVID-19 in cancer screening is not fully understood.This study aimed to assess the efficiency of global cancer screening programs before and during the COVID-19 pandemic and to promote potential cancer-screening strategies for the next pandemic.Electronic searches in PubMed,Embase,and Web of Science,and manual searches were performed between January 1,2020 and March 1,2023.Cohort studies that reported the number of participants who underwent cancer screening before and during the COVID-19 pandemic were included.The methodological quality of the included studies was assessed using the Newcastle-Ottawa Scale.Differences in cancer-screening rates were estimated using the incidence rate ratio(IRR).Fifty-five cohort studies were included in this meta-analysis.The screening rates of colorectal cancer using invasive screening methods(Pooled IRR=0.52,95%CI:0.42 to 0.65,p<0.01),cervical cancer(Pooled IRR=0.56,95%CI:0.47 to 0.67,p<0.01),breast cancer(Pooled IRR=0.57,95%CI:0.49 to 0.66,p<0.01)and prostate cancer(Pooled IRR=0.71,95%CI:0.56 to 0.90,p<0.01)during the COVID-19 pandemic were significantly lower than those before the COVID-19 pandemic.The screening rates of lung cancer(Pooled IRR=0.77,95%CI:0.58 to 1.03,p=0.08)and colorectal cancer using noninvasive screening methods(Pooled IRR=0.74,95%CI:0.50 to 1.09,p=0.13)were reduced with no statistical differences.The subgroup analyses revealed that the reduction in cancer-screening rates varied across economies.Our results suggest that the COVID-19 pandemic has had a noteworthy impact on colorectal,cervical,breast,and prostate cancer screening.Developing innovative cancer-screening technologies is important to promote the efficiency of cancer-screening services in the post-COVID-19 era and prepare for the next pandemic.

关键词： Cancer screening COVID-19 pandemic Cohort study Incidence rate ratio Meta-analysis

Recent Advances in Biomass-derived Porous Carbon Materials:Synthesis,Composition and Applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第1期40卷 3-19页

作者： ZHAI Ziqi LU Yumiao LIU Guangyong DING Wei-Lu CAO bobo HE Hongyan CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Mesoscience and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Longzihu New Energy Laboratory Zhengzhou Institute of Emerging Industrial TechnologyZhengzhou 450000P.R.China

Porous carbon materials(PCMs)play a pivotal role in diverse applications,such as energy storage,adsorption,catalysis,environmental remediation,and microwave adsorption.The selection of carbon precursors,in particular,is crucial for tailoring porous structures with specific functionalities.Biomass,with its rich carbon feedstock,abundant availability,renewability,and versatile structures,has emerged as a promising precursor for porous carbon material synthesis.This review comprehensively summarizes the recent advances in biomass-derived porous carbon materials(BPCMs)encompassing synthetic strategy,morphology,structural composition,and multiple applications.We first review synthetic approaches aiming at regulating porosity,followed by morphological and composition features of BPCMs,with a special emphasis on elucidating the dimensional clarification and heteroatom doping effects.The discussion then extends to the wide-ranging applications of BPCMs,covering energy-related applications and CO_(2) adsorption to environmental remediation.Finally,the review outlines the existing challenges and prospects in the field.In summary,this review systematically describes BPCMs and provides valuable guidance for researchers to select and synthesize BPCMs that meet specific functional requirements.

关键词： Biomass Porous carbon Pyrolysis Heteroatom-doping Supercapacitor CO_(2)adsorption

Selective nano-buckling improves the performance of graphene logic transistors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第2期11卷 95-96页

作者： Tong yang Ming yang Department of Applied Physics The Hong Kong Polytechnic University Research Centre for Nanoscience and Nanotechnology The Hong Kong Polytechnic University

The massive integration of silicon-based transistors into modern electronic devices greatly increases power consumption and heat generation/dissipation[1]. In this concern, transistors based on atomically-thin graphene that exhibit high electric and thermoelectric conductivities with negligible contact resistance,

关键词：

Deep Insight of Design,Mechanism,and Cancer Theranostic Strategy of Nanozymes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第2期16卷 165-217页

作者： Lu yang Shuming Dong Shili Gai Dan yang He Ding Lili Feng Guixin yang Ziaur Rehman Piaoping yang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China Yantai Research Institute Harbin Engineering UniversityYantai 264000People’s Republic of China Key Laboratory of Green Chemical Engineering and Technology of Heilongjiang Province College of Material Science and Chemical EngineeringHarbin University of Science and TechnologyHarbin 150040People’s Republic of China Department of Chemistry Quaid-i-Azam UniversityIslamabad 45320Pakistan

Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007,nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity,low cost,mild reaction conditions,good stability,and suitable for large-scale production.Recently,with the cross fusion of nanomedicine and nanocatalysis,nanozyme-based theranostic strategies attract great attention,since the enzymatic reactions can be triggered in the tumor microenvironment to achieve good curative effect with substrate specificity and low side effects.Thus,various nanozymes have been developed and used for tumor therapy.In this review,more than 270 research articles are discussed systematically to present progress in the past five years.First,the discovery and development of nanozymes are summarized.Second,classification and catalytic mechanism of nanozymes are discussed.Third,activity prediction and rational design of nanozymes are focused by highlighting the methods of density functional theory,machine learning,biomimetic and chemical design.Then,synergistic theranostic strategy of nanozymes are introduced.Finally,current challenges and future prospects of nanozymes used for tumor theranostic are outlined,including selectivity,biosafety,repeatability and stability,in-depth catalytic mechanism,predicting and evaluating activities.

关键词： Nanozymes Classification Prediction and design Catalytic mechanism Tumor theranostics

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： yang yang Guanxin Yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers respectively.The results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making