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Development of solar-blind AlGaN 1.8x1.8 Ultraviolet Focal Plane Arrays

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Science China(Technological sciences) 2008年第6期51卷 820-826页

作者： YUAN YongGang1. ZHANG Yan1. CHU KaiHui1. LI XiangYang1. ZHAO DeGang2 & YANG Hui2 1.State Key Laboratories of Transducer Technology, Shanghai institute of Technical Physics,{1., Shanghai 200083, China 2 institute of Semiconductors,{1., beijing 1.0083, China State Key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

This paper reports the development of solar-blind aluminum gallium nitride (AlGaN) 1.8×1.8 UV Focal Plane Arrays (FPAs). The back-illuminated hybrid FPA archi- tecture consists of an 1.8x1.8 back-illuminated AlGaN PIN detector array that is bump-mounted to a matching 1.8x1.8 silicon CMOS readout integrated circuit (ROIC) chip. The 1.8×1.8 p-i-n photodiode arrays with cuton and cutoff wave-lengths of 233 and 258 nm, with a sharp reduction in response to UVB (280―320 nm) light. Several examples of solar-blind images are provided. This solar-blind band FPA has much better application prospect.

关键词： AlGaN photodiode ultraviolet FPA solar-blind

Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

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Journal of Systematics and Evolution 2011年第6期49卷 539-545页

作者： 1.2Hong YAO 1.i-Bo LUO 1.State Key Laboratory of Systematic and Evolutionary Botany,institute of Botany,{1. academy of sciences,beijing 1.0093,China) 2(Graduate University of the chinese academy of sciences,beijing 1.0049,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) *Correspondence: Yi-Bo LUO *Correspondence: E-mail: luoyb@*** Tel.: 86-1.-6283651. Fax: 86-1.-62590843.

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3-4 hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2 h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science China Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1.& LIU Fei2,3 1. National Marine Environmental Forecasting center,{1. 1.0081. China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, institute of Atmospheric Physics, chinese academy of sciences,{1. 1.0029, China 3. Graduate University of chinese academy of sciences,{1. 1.0049, China 1. National Marine Environmental Forecasting center Beijing 100081 China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Graduate University of chinese academy of sciences Beijing 100049 China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Global convergence property of s-dependent GFR conjugate gradient method

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chinese Science Bulletin 1998年第23期43卷 1959-1965页

作者： WANG Changyu 1.2 and ZHANG Yuzhong\+1.1. institute of Operations Research in Qufu Normal University, Qufu 2731.5, China 2. institute of Applied Mathematics, chinese academy of sciences, beijing 1.0080, China institute of Operations Research Qufu Normal University Qufu China institute of Applied Mathematics Chinese Academy of Sciences Beijing China

An \%S\%_dependent GFR method and a generalized conjugate gradient method are designed. Two estimated values of upper bounds for the ratio of β k to β FR k are given. The two convergence theorems are proved. The global convergent properties of \%s\%_dependent GFR method are obtained adopting several choice strategies of steplength and some results in recent literature are extended.

关键词： steplength linear search global convergence conjugate gradient.

Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science China Earth sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1. 2, QIN Boqiang1. HU Weiping1. WANG Sumin1. CHEN Yuwei1.& CHEN Weimin1.1. Nanjing institute of Geography & Limnology,{1., Nanjing 21.008, China 2. Graduate School of the{1., beijing 1.0039, China 1. Nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1.98—2004 and total suspended solids (TSS), wind speeds of the total1. stations in typical lake regions during 1.93—2003, this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1.93—2003, the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04 to1.95 m with a mean value of 1.35±0.23 m. The PAR euphotic depth fell into 3 spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1. 1.4, 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 400 nm, and a peak at the green light wave band of around 580 nm. In 1.98 and1.99, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2w

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological

Fluorescence response of hypocrellin B to the environmental changes in a mimic biological membrane——liposome

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Science China chemistry 2004年第4期47卷 335-339页

作者： JIN Xuanye1.2, ZHAO Yuewei1. XIE Jie1.& ZHAO Jingquan1.1. CAS Key Laboratory of Photochemistry,{1. for Molecular Science, institute of chemistry, chinese academy of Science, beijing 1.0080, China 2. School of Earth sciences and Resources, China University of Geosciences, beijing 1.0083, China 1. CAS Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Science 100080 Beijing China 2. School of Earth sciences and Resources China University of Geosciences 100083 Beijing China

Liposome is well known as not only a drug-delivery system but also a simple model for biological membranes. It was reported that fluorescence properties of hypocrellins were changeable over some extreme pH values. In the current work, the effects of the microenvironments on the fluorescence properties of HB in liposome, including approximately physiological range of pH values pH = 6.0-8.0, concentration of cholesterols and ionic strength of the solution, were studied. It was found that the fluorescence intensity of HB was sensitive to and also regulated by the microenvironments. When concentration of cholesterols and ionic strength keep invariable in PBS solution, there exists the maximum for the fluorescence of HB-liposome at pH 7.4 while the minimum for that of HB at pH 7.0. In addition, when pH value keeps constant (7.2), there exists the maximum at the ionic strength of 0.1. mol/kg while that at the concentration of 6×1.?4 mol/L for cholesterols. On the other hand, in PBS solution, the lower the ionic strength is, the higher the fluorescence intensity is. The environment-sensitive fluorescence may be potentially applicable to probe some specific environmental features in cells or tissues.

关键词： microenvironment hypocrellin B liposome fluorescence

Dynamic tree-based authenticated group key exchange protocol

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Science China(Information sciences) 2010年第8期53卷 1591-1602页

作者： LI Hui 1.2 , WU ChuanKun 1.& TENG JiKai 1.2 1.State Key Laboratory of Information Security, institute of Software,{1., beijing 1.01.0, China 2 Graduate University of{1., beijing 1.0049, China 1. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Authenticated group key exchange protocols allow a group of users over a public network to establish a shared secret key for the subsequent cryptographic goals. In this paper, we extend BD-II scheme into a dynamic setting, and propose a tree-based authenticated key exchange protocol which is more suitable for dynamic groups in such as ad hoc networks. Our protocol is proven secure in random-oracle model. Additionally, we analyze the costs of our protocols in both communication and computation terms, and compare its performance with three well-known protocols.

关键词： tree-based group key exchange dynamic provable security

Human remains and the environment of Early Pleistocene in the Nihewan Basin

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Science China Earth sciences 2004年第5期47卷 437-444页

作者： CAI Baoquan1.& LI Qiang2 1. Department of History, Xiamen University, Fujian 361.05, China 2. institute of Vertebrate Palaeontology and Palaeoanthropology,{1., beijing 1.0044, China Xiamen Univ Dept Hist Fujian 361005 Peoples R China chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China

A new Early Pleistocene Paleolithic site was found in July 2001.in the Nihewan Ba-sin, Hebei Province. Totally 500 mammal specimens assigned to 21.species and 5 lithic artifacts were collected. The coexistence of Allophaiomys deucalion, Borsodia chinensis and Yangia tingi provides important evidence of chronology. On the basis of the comparison of mammalian fauna, the date of Paleolithic artifacts is probably earlier than 1.8 MaBP, possibly 2.0 MaBP. This is the earliest evidence of hominid activity found so far in North China. The hominid at that time in the Nihewan Basin lived in an environment of arid grasslands with scattered trees of temperate zone. This discovery is significant to the study of human origin and cultural development.

关键词： human remains, environment, Early Pleistocene, Nihewan.

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1. 2 , ZHANG Youshui 3 1. institute of Mountain Hazards and Environment,{1., Chengdu 61.041. Sichuan, China 2. Graduate University of{1., beijing 1.0049, China 3. institute of Geographical sciences and Natural Resources Research,{1., beijing 1.01.1. China institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China institute of Geographical{1. Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 259 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)