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一种先进的双光束光度量热系统:—DPA7双光束光度量热装置...
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作者 冯京毅 《国外分析仪器技术与应用》 1989年第1期54-57,共4页
关键词 光度量热系统 DPA7 DSC7
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美国PERKINELMER DPA7双光束光度量热装置简介
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作者 林泽恩 《北光通讯》 1990年第3期36-38,共3页
关键词 光度量热装置 紫外分析仪 量热计
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白光LED用YAG黄色荧光粉实用中发射光谱的测量方法 被引量:4
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作者 徐艳芳 张国生 +1 位作者 李路海 丁莹琨 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2013年第7期1834-1838,共5页
提出了一种YAG荧光粉在实用蓝光激发下发射光谱测量的新方法。通过采用高斯函数和费米函数拟合及模拟退火优化技术,得到了混合发光光谱的数学拟合函数,从而分离出荧光粉的发射光谱,进一步表征其发光性能。实验样品的测量结果表明,与简... 提出了一种YAG荧光粉在实用蓝光激发下发射光谱测量的新方法。通过采用高斯函数和费米函数拟合及模拟退火优化技术,得到了混合发光光谱的数学拟合函数,从而分离出荧光粉的发射光谱,进一步表征其发光性能。实验样品的测量结果表明,与简单的截切分离方法比较,具有不可忽略的光度量和色度量差异。量子效率、发光效率和能量效率等光度量的差异均高于1%,相关色温相差达几十K,色品坐标、主波长和色纯度等色品指标也产生差异,但半峰带宽变化不大,荧光发光的峰值波长则基本不受影响。实验结果表明,所建立方法能够提高实用条件下YAG黄色荧光粉发射光谱的测量准确性。 展开更多
关键词 YAG荧 发射 谱分离 光度量 度量
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光积分球非中性问题的讨论
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作者 张保洲 郝允祥 《北京师范大学学报(自然科学版)》 CAS 1985年第3期68-70,共3页
本文对光积分球的非中性及其对光度测量的影响做了定量的讨论,给出了积分球分光透过率与积分球内壁分光反射率之间的关系。还给出了减少积分球非中性的方法和措施。
关键词 积分球 透过率 光度量 可见谱区 度测量 反射 漫反射率 反射板 定量的 入射窗
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PR—921型光度测量仪
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作者 程上彝 杨翊 白剑 《光学仪器》 1997年第3期33-39,共7页
研制的PR—921型光度自动测量仪是用MSC—51单片机系统对光度量进行双通道数据采集、处理、显示。与IBM—PC微机可串行双向通讯。仪器与积分球配接,能自动测量光源的光通量;与光纤测试仪配接,能测量光纤的传输特性或衰减特性。
关键词 光度量 单片机 度测量仪 原理 数据采集
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SG—601光度计的原理及其定标方法 被引量:1
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作者 贾祥有 《光学仪器》 1995年第4期84-84,共1页
SG-601光度计是根据用户需要而研制和生产的精密仪器。它的基本原理与照度计类同。但是在二次仪表电子线路的设计,线性工作范围方面,则要求更高。SG-601是一种高精度、高分辨率的光度计。其准确度、线性度和稳定性都很高。由光电探... SG-601光度计是根据用户需要而研制和生产的精密仪器。它的基本原理与照度计类同。但是在二次仪表电子线路的设计,线性工作范围方面,则要求更高。SG-601是一种高精度、高分辨率的光度计。其准确度、线性度和稳定性都很高。由光电探测器接收的光信号,输入到高阻抗、高稳定性的运算放大器,进行I-V转换,以实现零负载效应。从而使回路中产生的光电流与接收器表面的光照度成线性关系。由于硅光电池具有很高的反向结电阻与运算放大器匹配良好,从而减少了光电流放大器的零点漂移,提高了光度计的稳定性。光电信号经放大后,输入A/D转换、再通过驱动译码,LED显示,给出正确的测试结果。 展开更多
关键词 照度 光度量 定标 度计
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光度计量及仪器
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《中国光学》 EI CAS 1998年第6期2-2,共1页
TB96 98063512PR-921型光度测量仪=Model PR-921 luminometer[刊,中]/程上彝,白剑(浙江大学光科系.浙江,杭州(310027)),杨翊(杭州应用工程技术学院.电机系.浙江,杭州(310012))//光学仪器.-1997。
关键词 自动测量仪 应用工程 学仪器 浙江大学 技术学院 度计量 杭州 光度量 电机 单片机系统
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光度计量及仪器
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《中国光学》 EI CAS 1998年第2期4-4,共1页
TB96 98020723多光谱问题中辐射量与光度量之间的关系=Relationsbetween radiometry and photometry in multispectraltechnique[刊,中]/周胜利(航天部508所.北京(100081))∥光学技术.-1997,(2).
关键词 光度量 学技术 辐射度量 仪器 度计量 辐射量 北京 自动测试 公路工程监理
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Photosynthetic induction responses of Pinus koraiensis seedlings grown in different light environments 被引量:5
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作者 周永斌 殷有 +1 位作者 刘兴双 王庆礼 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期246-248,共3页
The time processes of photosynthetic induction responses to various irradiances in Korean pine (Pinus koraiensis) seedlings grown in open-light environments and in understory of forest were studied in an area near the... The time processes of photosynthetic induction responses to various irradiances in Korean pine (Pinus koraiensis) seedlings grown in open-light environments and in understory of forest were studied in an area near the Research Station of Changbai Mountain Forest Ecosystems, Jilin Province, China from July 15 to August 5, 1997. The results showed that at 200 靘olm-2s-1 photosynthetic photon flux density (PPFD) and 500 靘olm-2s-1 PPFD, the induction time for the photosynthetic rates of understory-grown seedlings to reach 50% and 90% steady-state net photosynthetic rates was longer than that of the open-grown seedlings. The induction responses of open-growth seedlings at 500 靘olm-2s-1 PPFD were slower than those at 200 靘olm-2s-1 PPFD, but it was the very reverse for understory-growth seedlings, which indicates that the photosynthetic induction times of Korean pine seedlings grown in the understory depended on the sunfleck intensity. 展开更多
关键词 Pinus koraiensis seedlings Photosynthetic induction responses Natural light
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Determination of the Trace Element Contents in Plants Using Atomic Absorption Spectrophotometer 被引量:37
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作者 高淑云 《Agricultural Science & Technology》 CAS 2008年第2期6-9,共4页
The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results sh... The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results show that Se in burdock stem, skin and leaf are 32.40, 48.63, 38.10 μg/g, respectively; Cd in burdock stem, skin and leaf are 0. 160 0, 0. 300 0, 0. 140 0 μg/g, respectively; Cd in burdock stem, skin and leaf are 2. 020, 3. 960, 2. 410 μg/g, respectively. In the ginkgo and ginko leaf, Se contents are 17.63 and 16.91 μg/g, respectively ; for Cd are 0. 181 0 and 0.2020μg/g, respectively ; for Pb are 3. 572 and 4. 021 μg/g, respectively. In garlic, Se, Cd and Pb are 73. 900 0, 6. 900 0 and 0. 390 0, respectively. All the standard deviations of measured results are below 2.3%, recovery rate are from 99% to 101%. 展开更多
关键词 Trace elements GFT AAS BURDOCK GINKGO GARLIC
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颜色在夜景照明中的应用——初探重庆市夜景照明中颜色应用的问题 被引量:1
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作者 蔡春颖 《灯与照明》 2004年第3期21-24,共4页
新世纪的城市夜景照明应该光亮、优美 ,富有个性 ,而今各大城市都在努力创造这样的夜间环境。针对照明工程中实际问题 ,该文对城市夜景照明中合理的运用色度学理论 ,营造一个舒适光环境下的城市夜间形象 。
关键词 光度量 颜色 色彩 色度学 城市夜景照明
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Impacts of bird abundance, activity height and light intensity on the number of birds captured by mist netting 被引量:2
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作者 邹发生 陈桂珠 杨琼芳 《Chinese Birds》 2010年第4期221-229,共9页
To understand better the impact on mist net capture rates of the activity height of birds, light intensity, bird richness and abundance, we compared data from mist nets and point counts at the Jianfengling Forest Area... To understand better the impact on mist net capture rates of the activity height of birds, light intensity, bird richness and abundance, we compared data from mist nets and point counts at the Jianfengling Forest Area, Hainan Island. Mist-nets were operated for a total of 7135 net-hours. A total of 587 individuals of 45 bird species were captured. The total mean capture rate was 8.6 ± 10.4 per 100 net-hours. A total of 4932 individuals of 107 bird species were recorded by visual observation alone and 7616 individuals of 120 species were recorded in a visual and aural combination. The Grey-cheeked Fulvetta (Alcippe morrisonia) was the most abundant species, accounting for 38.7% of total captures, 27.9% of visual observations and 22.2% of visual + aural observations. The capture number was correlated with the number observed. Thirty-one species were more likely to be captured than observed. Canopy species, such as members of the Corvidae and Dicruridae, were seldom captured. For all ground feeding species, the capture number was greater than that of observation. Some cryptic species, such as the Lesser Wren Babbler (Napothera epilepidota), Spotnecked Babbler (Stachyris striolata) and Cuckoo Owl (Glaucidium cuculoides) also had a higher relative capture rate than that of observations. There was a significant relationship between light intensity and the number of birds captured. 展开更多
关键词 activity height bird abundance light intensity mist nets point counts
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Numerical Study of Optimization of Layer Thickness in Bilayer Organic Light-Emitting Diodes 被引量:3
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作者 彭应全 张磊 张旭 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第5期454-460,共7页
A numerical model for bilayer organic light-emitting diodes (OLEDs) is developed under the basis of trapped charge limited conduction.The dependences of the current density on the layer thickness,trap properties and c... A numerical model for bilayer organic light-emitting diodes (OLEDs) is developed under the basis of trapped charge limited conduction.The dependences of the current density on the layer thickness,trap properties and carrier mobility of the hole transport layer (HTL) and emission layer (EML) in bilayer OLEDs of the structure anode/HTL/EML/cathode are numerically investigated.It is found that,for given values of the total thickness of organic layers,reduced depth of trap,total density of trap,and carrier mobility of HTL as well as EML,there exists an optimal thickness ratio of HTL to EML,by which a maximal quantum efficiency can be achieved.Through optimization of the thickness ratio,an enhancement of current density and quantum efficiency of as much as two orders of magnitude can be obtained.The dependences of the optimal thickness ratio to the characteristic trap energy,total density of trap and carrier mobility are numerically analyzed. 展开更多
关键词 organic light-emitting diodes BILAYER OPTIMIZATION
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A study on the shade tolerance of Muehlewbeckia complera
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作者 岳桦 关学瑞 姜斌斌 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期83-85,J004,共4页
Muehlewbeckia complera was introduced to China in 2002 as indoor-hanging ornamental foliage plant. The experiment of the shade tolerance for this species was carried out in different light intensities (0.14–946.00 μ... Muehlewbeckia complera was introduced to China in 2002 as indoor-hanging ornamental foliage plant. The experiment of the shade tolerance for this species was carried out in different light intensities (0.14–946.00 μmol·m?2·s?1). After 40 days in experimental areas, leaf photosynthentic characteristics indexes ofM. complera in different photosynthesis active radiation (PAR) were measured with LI-COR6400 apparatus, such as the light compensation point, light saturation point, and maximum net photosynthesis rate, at the same time, the increments of total leaf area and leaf amount were measured. The results showed that the optimum light intensity range forM. complera was from 9.26 μmol·m?2·s?1 to 569.00 μmol·m?2·s?1 (463–28150 lx, relative humidity (RH) for 46–60%, temperature at 16–22°C). Under this condition, leaf photosynthetic efficiency was tiptop. AlthoughM. complera belonged to the moderate sun-adaptation plant species, the plant growth was inhibited when PAR increased to the level of 569.000 μmol·m?2·s?1 or above.M. complera could sprout new leaves in photosynthesis active radiation of 0.16–19.22 μmol·m?2·s?1 (8–961 lx), or 10 μmol·m?2·s?1 for above 6 h. Keywords Muehlewbeckia complera - Shade tolerance - Cultivation - Photosynthesis CLC number S602.1 Document code A Foundation item: This study was supported by the Research Foundation of Northeast Forestry University.Biography: YUE Hua (1962-), female, Associate professor in Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Muehlewbeckia complera Shade tolerance CULTIVATION PHOTOSYNTHESIS
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Study on Matter Production and Population Photosynthetic Characteristics of High-yielding Spring Maize under Different Modes
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作者 王永亮 梁志英 +3 位作者 杨治平 郭军玲 郭彩霞 王琦 《Agricultural Science & Technology》 CAS 2016年第12期2779-2783,共5页
In order to construct a good population structure, improve the light energy utilization ratio, and give a full play to the high-yielding potential of spring maize, the effects of maize variety, planting density and fe... In order to construct a good population structure, improve the light energy utilization ratio, and give a full play to the high-yielding potential of spring maize, the effects of maize variety, planting density and fertilizer management on matter production and population photosynthetic physiological indices of spring maize were investigated under three different modes (traditional mode, optimized mode and high- yielding mode). The results showed that compared with those under the traditional mode, the yield of spring maize under the optimized mode and high-yielding mode was increased by 10.79% and 27.62%, respectively, and the barren tip length was reduced significantly. Among the three modes, the leaf area index (LA/), leaf area duration (LAD), dry matter accumulation (DMA) and crop growth rate (CGR) all ranked as high-yielding rnode's〉optimized mode's〉traditional mode's. In conclusion, optimized variety, appropriately increased planting density and strengthened fertilizer management are the key measures to obtain high yield of spring maize. 展开更多
关键词 Spring maize High yield High efficiency Photosynthetic performance DENSITY
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Optimal Light Intensity and Nitrogen-to-Phosphorus Ratio for Growth of Nitzschia capitellata Hust. 被引量:1
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作者 晏妮 胡晓红 陈椽 《Agricultural Science & Technology》 CAS 2014年第3期453-456,共4页
Objective] The aim was to explore the potential of Nitzschia capitel ata as excel ent baits and bioenergy, and the optimal light intensity and nitrogen-to-phos-phorus (N/P) ratio suitable for its growth were researc... Objective] The aim was to explore the potential of Nitzschia capitel ata as excel ent baits and bioenergy, and the optimal light intensity and nitrogen-to-phos-phorus (N/P) ratio suitable for its growth were researched as wel . [Method] With light intensity gradient set, Nitzschia capitel ata was cultured with the same nutrients at (25 ±1) ℃ and light cycle at 12 h/d to select optimal light intensity. Then, Nitzschia capitel ata was cultured with the same condition, and nitrogen-to-phospho-rus ratios at 5∶1, 6∶1, 7∶1 and 8∶1. [Result] With light intensity at 3 000 lx, specific growth rate and standing stock achieved the highest at 0.51 d-1 and 7.97×104 cel s/ml. The growth condition with nitrogen-to-phosphorus ratio at 6∶1 was the most suitable for Nitzschia capitel ata growth. [Conclusion] The optimal light intensity and nitrogen-to-phosphorus ratio were 3 000 lx and 6∶1, respectively, for Nitzschia capitel ata. 展开更多
关键词 Nitzschia capitellata Hust. Light intensity Specific growth rate Standingstock Nitrogen-to-phosphorus ratio
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浅谈现代住宅照明技术
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作者 张华昕 《建筑施工》 2005年第5期46-48,共3页
照明是居住环境的一个重要组成部分,综合现代住宅对照明的要求,论述了现代住宅照明设计的原则,根据住宅内不同的空间,选用不同的灯具及照明方式,以满足功能的需要及艺术效果。
关键词 照明技术 环境质量 光度量 局部照明 防火
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宾得 Optio S7
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《数字通信》 2006年第18期29-29,共1页
Optio S7为宾得新近推出的超薄卡片机,该柜机延续着S6的特色,轻巧、方便携带,机身尺寸为85.5mm×53.5mm×19.5mm,不安装电池时仅重100g,S7搭载700万有效像素的CCD,3倍光学变焦,高感光度模式可在夜间光照不足的情况下自... Optio S7为宾得新近推出的超薄卡片机,该柜机延续着S6的特色,轻巧、方便携带,机身尺寸为85.5mm×53.5mm×19.5mm,不安装电池时仅重100g,S7搭载700万有效像素的CCD,3倍光学变焦,高感光度模式可在夜间光照不足的情况下自动调整ISO感光度量高速1600。另外它还具有人脸识别技术,可“让幅机自动分辨画面中所出现的人脸而进行对焦。 展开更多
关键词 OPTIO 宾得 人脸识别技术 3倍学变焦 自动调整 有效像素 照不足 高感 CCD 光度量
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23届国际照明会议有关专题发言介绍(续)
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作者 章海骢 《光源与照明》 1996年第1期16-19,共4页
二、专题讨论会的专题报告 1.“等效亮度”主持人Ikeda(日本Kgoto大学) 等效亮度(Leg)是用视觉函数来描写照明效果的有效工具,来源于不同颜色刺激下的明度并将用来定义适合各种视觉功能相关的光度量。此值的概念、空义、量标和应用等... 二、专题讨论会的专题报告 1.“等效亮度”主持人Ikeda(日本Kgoto大学) 等效亮度(Leg)是用视觉函数来描写照明效果的有效工具,来源于不同颜色刺激下的明度并将用来定义适合各种视觉功能相关的光度量。此值的概念、空义、量标和应用等方面都尚未统一,CIE正致力于发展这种新的光度学型式。 随着视环境和视觉科学的发展,用CIE 2°视场得到的亮度是有缺点的。1994年在维也纳召开的专题讨论会上一致同意采纳等效亮度(Leg)这个名词并依此计算明度和视力这一类视觉效果,以介决CIE 2°明视亮度的不适用的状况。 在讨论会上,集中讨论了为什么需要Leg,如何定义,如何用此概念发展为新的光度量或光度系统。等效亮度把不同颜色的刺激明度和视力都作为一种视感觉考虑进去,特别是短波分量对瞳孔大小的影响,那么应采纳什么视觉函数来定义Leg,应该是什么样的参考刺激与之适应呢? 展开更多
关键词 等效亮度 国际照明 专题发言 不确定度 度学 照明设计 标准灯 专题讨论会 短波分量 光度量
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Organic Photovoltaic Cells with Improved Performance Using Bathophenanthroline as a Buffer Layer 被引量:5
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作者 王娜娜 于军胜 +1 位作者 林慧 蒋亚东 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期84-88,I0002,共6页
The role of bathophenanthroline (Bphen) as a buffer layer inserted between fullerene (C60) and Ag cathode in organic photovoltaic (OPV) cell was discussed. By introducing Bphen as a buffer layer with thicknes fr... The role of bathophenanthroline (Bphen) as a buffer layer inserted between fullerene (C60) and Ag cathode in organic photovoltaic (OPV) cell was discussed. By introducing Bphen as a buffer layer with thicknes from 0 to 2.5 nm, the power conversion efficiency of the OPV cell based on copper phthalocyanine (CuPc) and C60 was increased from 0.87% to 2.25% under AM 1.5 solar illumination at an intensity of 100 mW/cm^2, which was higher than that of bathocuproine used as a buffer layer. The photocurrent-voltage characteristics showed that Bphen effectively improves electron transport through C60 layer into Ag electrode and leads to balance charge carrier transport capability. The influence of Bphen thickness on OPV cells was also investigated. Furthermore, the absorption spectrum shows that an additional Bphen layer enhances the light harvest capability of CuPc/C60. 展开更多
关键词 Organic photovoltaic cell Buffer layer Bathophenanthroline Charge carrier transport
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