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	The contribution of insects to global forest deadwood decomposition 期刊论文 OAI收割 NATURE, 2021, 卷号: 597, 期号: 7874, 页码: 77+ 作者: Seibold,Sebastian; Rammer,Werner; Hothorn,Torsten; Seidl,Rupert; Ulyshen,Michael D. \| 收藏 \| 浏览/下载：91/0 \| 提交时间：2022/04/02 COARSE WOODY DEBRIS CARBON SINK CLIMATE TEMPERATURE METAANALYSIS TERRESTRIAL SEASONALITY GRASSLANDS INCREASES COMMUNITY
	Changes in the Response of the Northern Hemisphere Carbon Uptake to Temperature Over the Last Three Decades 期刊论文 OAI收割 GEOPHYSICAL RESEARCH LETTERS, 2018, 卷号: 45, 期号: 9, 页码: 4371-4380 作者: Bastos, A (Bastos, Ana); Piao, SL (Piao, Shilong); Yin, Y (Yin, Yi); Ciais, P (Ciais, Philippe); Liu, HY (Liu, Hongyan) \| 收藏 \| 浏览/下载：29/0 \| 提交时间：2019/06/04 ATMOSPHERIC CO2 SEASONAL CYCLE SURFACE-TEMPERATURE SOIL RESPIRATION EXCHANGE DIOXIDE ECOSYSTEMS INCREASES WINTER FLUX
	Hydrological Response of East China to the Variation of East Asian Summer Monsoon SCI/SSCI论文 OAI收割 2016 作者: Li F. X.; Chen, D.; Tang, Q. H.; Li, W. H.; Zhang, X. J. \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2017/11/09 yellow-river basin atmospheric circulation temperature increases soil-moisture yangtze-river detect trend precipitation rainfall climate streamflow
	Influence of sensitizer concentration on the upconversion luminescence of NaYF4: Yb3+, Er3+ nanoparticles (EI CONFERENCE) 会议论文 OAI收割 2012 2nd International Conference on Machinery, Materials Science and Engineering Applications, MMSE 2012, June 16, 2012 - June 17, 2012, Wuhan, China 作者: Zhao J. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 A series of NaYF4: Yb3+ Er3+ nanoparticles with different doping concentration were successfully prepared by the combination of coprecipitation and hydrothermal methods using sodium citrate as chelator. Upconversion luminescence can be observed in all of the samples at room temperature. Fixed the Er3+ concentration with 1 mol% unchanged the effect of the Yb3+ concentration on the upconversion luminescence of NaYF4: Yb3+ Er3+ samples were studied when the doped Yb3+ concentrations were 0 mol% 1 mol% 2 mol% 5 mol% 10 mol% and 20 mol% respectively. As increasing the Yb 3+ concentration the total intensity of the upconversion luminescence of the samples is increasing while the ratio of red to green emission increases firstly and then decreases. The maximum ratio value is 22.1 when the Yb3+ concentration is 10 mol%. It is found that the cross relaxation and cooperative sensitization effect are the reasons for the phenomenon above. (2012) Trans Tech Publications.
	Diagnostics of electron temperature and density in a capillary predischarge Ar plasma (EI CONFERENCE) 会议论文 OAI收割 2011 Academic International Symposium on Optoelectronics and Microelectronics Technology, AISOMT 2011, October 12, 2011 - October 16, 2011, Harbin, China 作者: Zhao Y.; Xie Y.; Zhao Y.; Zhao Y. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 The spectra of the argon plasma generated by capillary predischarge are observed in the experiments. The electron temperature and density are obtained with the method of spectrum analysis. The electron temperatures are approximately 0.7eV and the electron densities are about 11022 m-3. When increasing the pressure the electron temperature decreases and the electron density increases on the contrary. 2011 IEEE.
	Effect of interface on luminescence properties in ZnO/MgZnO heterostructures (EI CONFERENCE) 会议论文 OAI收割 Wei Z. P.; Lu Y. M.; Shen D. Z.; Wu C. X.; Zhang Z. Z.; Zhao D. X.; Zhang J. Y.; Fan X. W. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 A set of ZnO/MgZnO heterostructures with well widths Lw varying from 2 to 20 nm has been grown by plasma-assisted molecular-beam epitaxy (P-MBE). We present a room-temperature (RT) study of the well-width-dependent photoluminescence (PL) spectra and carrier lifetimes in ZnO/MgZnO heterostructures. Bi-exponential process is seen at RT time-decay curves of the luminescence from the well layers. The fast process is from the recombination of the free exciton while the slow process is attributing to the recombination of the localized exciton in the interface of ZnO and MgZnO. It is also confirmed from the PL peak shift of time-resolved PL spectra. With decreasing the well thickness the fast process gradually increases and dominantly contributes to the PL spectrum due to the interface improvement. 2006 Elsevier B.V. All rights reserved.
	Temperature-enhanced ultraviolet emission in ZnO thin film (EI CONFERENCE) 会议论文 OAI收割 Zhang Y. J.; Xu C. S.; Liu Y. C.; Liu Y. X.; Wang G. R.; Fan X. W. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 We have studied the structural and optical properties of ZnO thin films prepared by thermal oxidation of ZnS films deposited by plasma assisted electron-beam evaporation on Si(1 0 0) substrates. The transformation from zinc blende ZnS to hexagonal wurtzite ZnO is confirmed by Raman and X-ray diffraction (XRD) measurement. For the sample thermally oxidized at 600 C for 2 h a novel UV emission peak Ix located at 3.22 eV (385 nm) has been observed. The temperature-dependent photoluminescence spectra show that the integrated intensity of Ix increases exponentially with increasing temperatures within the measuring temperature range from 80 to 300 K but the peak position remains nearly constant. We explain this behavior in terms of electron tunneling into the radiative recombination centers.
	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.
	Optical characterization of bare CdSe and CdSe/CdS core/shell nanocrystals (EI CONFERENCE) 会议论文 OAI收割 ICO20: Biomedical Optics, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu L.; Yu B.; Liu L. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 Thiol-capped CdSe/CdS core/shell nanocrystals (NCs) which show high luminescence quantum yield are synthesized in an aqueous solution. UV-Vis absorption spectroscopy and photoluminescence (PL) spectroscopy are employed to analyze optical characters and stabilities of NCs. Furthermore PL properties are studied in a temperature range between 77K and 300K. The PL peak position of bare CdSe NCs shifts toward shorter wavelengths and the band becomes sharper with decreasing temperature. On the same condition the PL peak position of CdSe/CdS core/shell NCs keeps unconverted nearly with the variation of temperature. Photostability of bare CdSe NCs and CdSe/CdS core/shell NCs are compared under the 325nm laser irradiation. It takes 78 seconds that the PL intensity declines to the half for CdSe NCs but 442 seconds for CdSe/CdS core/shell NCs. The fluorescence decay lifetime increases about six times after overcoating. The results indicate that the CdS shell can improve the low temperature PL stability and photostability of CdSe NCs effectively.