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	Variation in leaf chlorophyll concentration from tropical to cold-temperate forests: Association with gross primary productivity 期刊论文 OAI收割 ECOLOGICAL INDICATORS, 2018, 卷号: 85, 页码: 383-389 作者: Li, Ying; Liu, Congcong; Zhang, Jiahui; Yang, Hao; Xu, Li \| 收藏 \| 浏览/下载：38/0 \| 提交时间：2019/05/23 Chlorophyll CM a/b Community Functional traits GPP Nutrients Photosynthesis Pigments Spatial variation Trait Forest
	基于二噻吩并咔唑与苯并噻二唑的 D-A 型共轭聚合物的合成与表征学位论文 OAI收割硕士, 中国科学院长春应用化学研究所: 中国科学院研究生院, 2015 作者: 荣梓清收藏 \| 浏览/下载：56/0 \| 提交时间：2016/04/27 由于给体片段（D）和受体片段（A）间的电荷转移 D-A型共轭高分子通常具有较小的光学带隙且分子偶极矩较大分子间相互作用较强利于获得高的载流子迁移率因此 D-A型共轭聚合物是有机太阳能电池材料领域的研究热点。另一方面稠环分子由于具有刚性平面的构型重组能小等优点而被广泛引入D-A型共轭聚合物体系中。因此本文以二噻吩并[2 3-b:7 6-b]咔唑（C1）和二噻吩并[3 2-b:6 7-b]咔唑（C2）两个稠环单元作为给体片段苯并噻二唑（BT）单元作为受体片段合成了一系列D-A型共轭聚合物并且对它们的光物理性质电化学性质载流子传输和光伏特性进行了系统研究主要成果和创新点如下：（1）合成了基于二噻吩并咔唑和烷氧基取代的BT单元的两个聚合物P(BT-C1)和P(BT-C2) 它们均是无定形聚合物。尽管P(BT-C1)和P(BT-C2)在分子结构上只有硫原子位置不同的差别但两者在长波长和短波长范围表现出完全相反的相对吸收强度。通过理论模拟可以发现两个聚合物骨架构象完全不同 P(BT-C1)的骨架较为弯曲而P(BT-C2)的骨架线性较好。因此基于P(BT-C2)的有机薄膜晶体管（OTFT）的迁移率较高达到5.4×10-3 cm2V-1s-1 而P(BT-C1)的OTFT迁移率较低为1.9×10-3 cm2V-1s-1。 P(BT-C2)的HOMO能级比P(BT-C1)深0.2 eV左右因此基于P(BT-C2)的体异质结有机太阳能电池（OSC）器件的开路电压（Voc）明显高于P(BT-C1) 而P(BT-C1)与PC71BM共混薄膜相分离更加明显导致P(BT-C1)的OSC器件的短路电流密度（Jsc）和填充因子（FF）较高两个聚合物的能量转换效率（PCE）相差不多均在5%左右。（2）以C2为给体单元 BT和二氟代BT为受体单元合成了两个共轭聚合物P(C6BT-C2)和P(C6BT2F-C2)。与P(BT-C2)相比 P(C6BT-C2)具有较高的热稳定性 HOMO能级升高光谱红移。在BT单元上引入F原子后聚合物的HOMO能级由P(C6BT-C2)的-5.00 eV降低到P(C6BT2F-C2)的-5.20 eV 同时帯隙变窄。理论模拟发现两者的分子平面性比P(BT-C2)有很大改善但分子骨架构象较为弯曲。基于P(C6BT-C2)与P(C6BT2F-C2)的OTFT器件在150 oC退火后载流子迁移率分别为4.8×10-3 和4.9×10-3 cm2V-1s-1 。由于与PC71BM共混薄膜的相分离不明显基于P(C6BT-C2)与P(C6BT2F-C2)的OSC器件的Jsc和FF较低 PCE均小于2%。
	Retrieval of snow depth in Northeast China using FY-3B/MWRI passive microwave remote sensing data (EI CONFERENCE) 会议论文 OAI收割 Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states Ren R.; Gu L.; Chen H.; Cao J. 收藏 \| 浏览/下载：136/0 \| 提交时间：2013/03/25 Comparing with optical remote sensing techniques passive remote sensing data have been proved to be effective for observing snowpack parameters such as snow depth and snow water equivalent which can penetrate snowpack without clouds interferences. The Microwave Radiation Imager (MWRI) loaded on the Chinese FengYun-3B (FY-3B) satellite is gradually used in the global environment research through November 2011. In this paper we proposed a snow depth retrieval algorithm to estimate snow depth in Northeast China using MWRI passive microwave remote sensing data. A decision tree method of snow identification was firstly designed to distinguish different snow cover conditions in order to eliminate other interference signals. After using the proposed decision tree method the processing results were further used to retrieve the snow depth in Northeast China. Finally the practical snow depth data and the MODIS data were collected for the accuracy assessment of the proposed snow depth retrieval method. The experimental results demonstrated that the RMSE of snow depth used the proposed method was approximately 3 cm in Northeast China. 2012 SPIE.
	Excitonic properties of vertically aligned ZnO nanotubes under high-density excitation (EI CONFERENCE) 会议论文 OAI收割 Lu Y. M.; Liang H. W.; Shen D. Z.; Zhang Z. Z.; Zhang J. Y.; Zhao D. X.; Liu Y. C.; Fan X. W. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 In this paper highly oriented and vertically arranged ZnO nanotubes are prepared on Al2O3 (0 0 0 1) substrate without employing any metal catalysts by plasma-assisted molecular beam epitaxy. The photoluminescence (PL) spectra at room temperature are studied under high excitation densities. Under lower excitation density (60 kW/cm2) PL spectrum shows that one strong free exciton emission (FE) locates at 3.306 eV. As the excitation density increases up to 200 kW/cm2 a new emission peak (Pn) located at low-energy side of FE is attributed to the spontaneous emission due to an exciton-exciton (Ex-E x) scattering process from two ground state excitons where one exciton is recombined by emitting a photon and the other is scattered into the excited states of n=2 3 4.... Under excitation density of 300 kW/cm 2 the stimulated emission originating from Ex-E x scattering is obtained. When the excitation density is above 580 kW/cm2 the emission from electron-hole plasma is observed in low-energy side of the P band and indicates a typical superradiation recombination processes with increasing excitation density. 2006 Elsevier B.V. All rights reserved.
	Fabrication and electron emission of carbon microtubes (EI CONFERENCE) 会议论文 OAI收割 Technical Digest of the 18th International Vacuum Nanoelectronics Conference, IVNC 2005, July 10, 2005 - July 14, 2005, Oxford, United kingdom 作者: Liu L.; Liu L.; Wang W.; Wang W. 收藏 \| 浏览/下载：38/0 \| 提交时间：2013/03/25 Carbon nanotubes have been attracting attention because of their unique physical properties and their application potential for field emission cathode. Carbon nanotubes possess the following properties favorable for field emission material such as a high aspect ratio and sharp tip high chemical stability high mechanical strength stable at high temperature. Some research works on carbon nanotubes field emitter and field emission display have been reported. Here a kind of carbon microtubes and its field emission properties are introduced. They have some different properties with carbon nanotubes and the density is lower than carbon nanotubes bundles. These carbon microtubes are directly synthesized by liquidoid epitaxy method on silicon substrates at low temperature. The field emission properties of carbon microtubes are reported too. Carbon microtubes film is synthesized in liquid by electrolysis. The graphite plate is as anode and n-silicon substrate with resistivity of 4-8 cm is as cathode. The electrolysis current is about 5-8mA/cm2 and applied voltage is 800-1500V. Temperatures of the methanol base solution is maintained at 60C in process of deposition of carbon microtubes. Carbon microtubes film is observed by scanning electron microscopy(SEM) as shown in fig.1(a b). The wall's thickness of carbon microtube is about 60nm. The diameter of carbon microtube is about 0.8 m. Raman spectrum of carbon microtubes film shows the two peaks at 1342and 1560cm-1. The field emission properties of carbon microtubes are measured in high vacuum chamber(10-5Pa). The emission area of carbon microtubes is 0.5cm 0.5cm. The threshold of field emission of the carbon microtubes film is about 3.6V/ m. Field emission property of carbon microtubes film is shown in fig.2. Another when the electric field between anode and cathode is 10V/ m the electric field distribution on single carbon microtube is also given after calculation according to electric field theory. Fig 3 shows that electric field distribution vertical section on the of single carbon microtube top with 2 m of highness. These results may help us to understand field emission properties of carbon microtubes. According to research results it is found that liquidoid synthesis is simple method to produce carbon microtubes cold cathode material and the carbon microtubes have better field emission properties. 2005 IEEE.
	Electrophoretic deposition and field emission properties of patterned carbon nanotubes (EI CONFERENCE) 会议论文 OAI收割 Zhao H.; H S.; Z L.; G Y.; Y J. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 Patterned carbon nanotubes on silicon substrates were obtained using electrophoretic method. The carbon nanotubes migrated towards the patterned silicon electrode in the electrophoresis suspension under the applied voltage. The carbon nanotubes arrays adhered well on the silicon substrates. The surface images of carbon nanotubes were observed by scanning electron microscopy. The field emission properties of the patterned carbon nanotubes were tested in a diode structure under a vacuum pressure below 5 10-4 Pa. The measured emission area was about 1.0 mm2. The emission current density up to 30 mA/cm2 at an electric field of 8 V/m has been obtained. The deposition of patterned carbon nanotubes by electrophoresis is an alternative method to prepare field emission arrays. 2005 Elsevier B.V. All rights reserved.