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Adsorption Behavior of a Water-soluble Porphyrin at the Glass-water Interface as Studied by Synchronous Total Internal Reflection Fluorescence Spectroscopy
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作者 MinNaYAO YaoQunLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第1期109-111,共3页
Total internal reflection fluorescence spectroscopy (TIRF) and synchronous scanning technique were combined to study the adsorption behavior of the meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) at the glass-water... Total internal reflection fluorescence spectroscopy (TIRF) and synchronous scanning technique were combined to study the adsorption behavior of the meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) at the glass-water interface without any surfactant. The pH dependence of synchronous fluorescence signal at the interface was analyzed. Both unprotonated (TPPS4-) and diprotonated (H2TPPS2-) forms of TPPS were observed at the interface. But the interface favored the adsorption of. The apparent estimated pKa2 value shifted from 5.00 in the bulk solution to 2.7 at the interface. STIRF provides a good technique to study multi-component systems at the interface. 展开更多
关键词 Total internal reflection fluorescence synchronous fluorescence water- soluble porphyrin pH dependence glass-water interface.
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水、旱栽培条件下稻谷粒型和粒重的相关分析及其QTL定位 被引量:25
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作者 郭咏梅 穆平 +2 位作者 刘家富 李自超 卢义宣 《作物学报》 CAS CSCD 北大核心 2007年第1期50-56,共7页
为了解水、旱栽培条件下水稻粒形和粒重的表型及QTL变化,以陆稻品种IRAT109和水稻品种越富构建的双单倍体群体为材料,系统分析了稻谷粒长、粒宽、粒重及长宽比在水、旱栽培条件下的相关性,并进行了数量性状基因位点的比较定位。结果... 为了解水、旱栽培条件下水稻粒形和粒重的表型及QTL变化,以陆稻品种IRAT109和水稻品种越富构建的双单倍体群体为材料,系统分析了稻谷粒长、粒宽、粒重及长宽比在水、旱栽培条件下的相关性,并进行了数量性状基因位点的比较定位。结果表明,水、旱条件下,粒长与长宽比和粒重均呈极显著正相关;粒宽与长宽比呈极显著负相关,与粒重极显著正相关,4个性状在水、旱条件间相关性都达极显著正相关。其中粒长的相关系数最高,达0.817,粒宽的相关系数最低,为0.457。表明粒长受水分影响最小而粒宽受水分影响较大。粒重、长宽比介于二者之间。两种条件下共检测到14个QTLs,分布于水稻1、5、6、7、10和12染色体上,其中控制粒长的5个,LOD值为1.93—5.11,贡献率为5.97%-28.85%;控制粒宽的1个,LOD值为2.39,贡献率为12.76%;控制长宽比的3个,LOD值为2.08-4.60。贡献率为7.78%。21.89%;控制粒重的5个,LOD值为2.68—9.45,贡献率为4.1%-14.8%。其中控制粒长的qGL-5及控制粒重的qGWt-1a和qGWt-1b在水、旱条件下均能检测到,在抗旱育种中可用于分子标记辅助选择籽粒性状。QTL分析的结果进一步验证了表型分析结果,粒宽相对易受土壤水分影响,粒长、粒重和长宽比,受水分胁迫影响较小,遗传比较稳定。 展开更多
关键词 水稻 粒型 粒重 加倍单倍体群体(DH系) 数量性状基因座位(QTL) 水、旱栽培
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Resource and Environmental Quality Changes and Adjustment Principles for Sustainable Development in Rapidly Developing Coastal Region of Southeastern China 被引量:10
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作者 ZHAO QIGUO Institute of Soil Science, the Chinese Academy of Sciences, P. O. Box 821, Nanjing 210008 (China) 《Pedosphere》 SCIE CAS CSCD 2001年第4期289-299,共11页
Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns... Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns in China, and the large export-oriented economy makes itself a strategic importance while China enters into international markets. The problems facing to this region include arable land reduction, land degradation aggravation, high percentage of built-up land with high rate of expansion, expanded non-point pollution, deteriorated water quality, decreasing biodiversity, destroyed ecosystems, severe air pollution, frequently occurred acid rain, and multi-pollutants. The important research fields in the near future should include a) influence of high-intensity exploitation of resources on changes of environment quality and its feedback; b) interface processes, key mechanisms and adjustment principles for degradation of water-, land-, and air-resources and environmental quality; c) evolvement processes and nurturing theory of biodiversity and ecological resources; and d) spatio-temporal variation and human-induced effects on regional resources and environment quality. Strategies for sustainable development in the region are as follows: a) controlling to ensure basic cultivated land area; b) enforcing remediation of polluted water environment, and controlling non-point pollution; c) strengthening ecological construction and ecological security; and d) controlling multi-pollution and preventing trace toxic pollutants. 展开更多
关键词 coastal region environment quality fast economic development southeastern China water- land resource
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Aggregate Characteristics During Natural Revegetation on the Loess Plateau 被引量:13
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作者 AN Shao-Shan HUANG Yi-Mei +1 位作者 ZHENG Fen-Li YANG Jian-Guo 《Pedosphere》 SCIE CAS CSCD 2008年第6期809-816,共8页
Field investigations and laboratory analysis were conducted to study the characteristics of soil water-stable aggregates during vegetation rehabilitation in typical grassland soils of the hilly-gullied loess area. The... Field investigations and laboratory analysis were conducted to study the characteristics of soil water-stable aggregates during vegetation rehabilitation in typical grassland soils of the hilly-gullied loess area. The relationship between water- stable aggregates and other soil properties was analyzed using canonical correlation analysis and principal component analysis. The results show that during the natural revegetation, the aggregates 〉 5 mm dominated and constituted between 50% and 80% of the total soil water-stable aggregates in most of the soil layers. The 2-5 mm aggregate class was the second main component. The mean value of water-stable aggregates 〉 5 mm within the 0-2 m soil profile under different plant communities decreased in the following order: Stipa grandis 〉 Stipa bungeana Trin. 〉 Artemisia sacrorum Ledeb. 〉 Thymus mongolicus Ronn. 〉 Hierochloe odorata (L.) Beauv. Clay, organic matter, and total N were the key factors that influenced the water stability of the aggregates. Total N and organic matter were the main factors that affected the water stability of the aggregates 〉 5 mm and 0.5-1 mm in size. The contents of Fe2O3, Al2O3, and physical clay (〈 0.01 mm) were the main factors which affected the water stability of the 1-2 and 0.25-0.5 mm aggregates. 展开更多
关键词 canonical correlation analysis loess area natural revegetation principal component analysis soil water- stable aggregates
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Fragile Watermarking of 3D Models Using Genetic Algorithms
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作者 Mukesh Motwani Rakhi Motwani Frederick Harris 《Journal of Electronic Science and Technology》 CAS 2010年第3期244-250,共7页
This paper describes a novel algorithm for fragile watermarking of 3D models. Fragile watermarking requires detection of even minute intentional changes to the 3D model along with the location of the change. This pose... This paper describes a novel algorithm for fragile watermarking of 3D models. Fragile watermarking requires detection of even minute intentional changes to the 3D model along with the location of the change. This poses a challenge since inserting random amount of watermark in all the vertices of the model would generally introduce perceptible distortion. The proposed algorithm overcomes this challenge by using genetic algorithm to modify every vertex location in the model so that there is no perceptible distortion. Various experimental results are used to justify the choice of the genetic algorithm design parameters. Experimental results also indicate that the proposed algorithm can accurately detect location of any mesh modification. 展开更多
关键词 3D mesh models fragile water- marking genetic algorithms SNR.
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Grass Litter Decomposition Rate and Water-Holding Capacity in Dry-Hot Valley of Jinshajiang River 被引量:3
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作者 ZHANG Mingzhong ZHU Hongye +2 位作者 JIN Jie SHI Liangtao SHA Yucang 《Wuhan University Journal of Natural Sciences》 CAS 2009年第1期92-96,共5页
The decomposition rate and the water-holding capacity of 6 kinds of grass litters were studied in the Jinshajiang river dry-hot valley. The results showed that the dry weight remains reduced with time but did not have... The decomposition rate and the water-holding capacity of 6 kinds of grass litters were studied in the Jinshajiang river dry-hot valley. The results showed that the dry weight remains reduced with time but did not have a direct correlation with time. The decomposition litters were affected by climate, character of litter, animalcule and soil animal. The climate factors of temperature and humidity were important especially. The water-holding capacity was in the sequence ofN. wightii (336%), P. notatum Flugge (248%), H. contortus (L.) Beauv (209%), B. pertusa (L.) A. Camus(206%), L endecaphylla Jacq (174%), D. annulatum (Forsk.) Stapf (168%). After 24 months decomposition the remaining dry weight of the litter was in the sequence as follows: 15.12% for N. wightii, 26.38% for I. endecaphylla Jacq, 27.23% for B. pertusa (L.) A. Camus, 30.78% for P. notatum Flugge, 39.72% for H. contortus (L.) Beauv and 39.76% for D. annulatum (Forsk.) Stapf. The decomposition rate and water-holding capacity ofN. wightii are at the highest level. It is important for the development, improvement and conservation of the grassland soil. 展开更多
关键词 grass litter dry-hot river valley decomposition rate water- holding capacity
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Highly efficient pure white polymer light-emitting devices based on poly(N-vinylcarbazole) doped with blue and red phosphorescent dyes 被引量:4
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作者 HU SuJun ZOU JianHua +7 位作者 ZHOU GuiJiang LI DongYun WU HongBin SU ShiJian WONG Wai-Yeung YANG Wei PENG JunBiao CAO Yong 《Science China Chemistry》 SCIE EI CAS 2011年第4期671-677,共7页
Efficient white-polymer-light-emitting devices (WPLEDs) have been fabricated with a single emitting layer containing a hole-transporting host polymer,poly(N-vinylcarbzole),and an electron-transporting auxiliary,1,3-bi... Efficient white-polymer-light-emitting devices (WPLEDs) have been fabricated with a single emitting layer containing a hole-transporting host polymer,poly(N-vinylcarbzole),and an electron-transporting auxiliary,1,3-bis[(4-tert-butylphenyl)-1,3,4-oxadiazolyl]-phenylene,codoped with two phosphorescent dyes:Iridium(III)bis (2-(4,6-difluorophenyl)-pyridinato-N,C2') picolinate (FIrpic) and home-made Ir-G2 for blue and red emission,respectively.With the structure of ITO/PEDOT:PSS 4083(40 nm)/emission layer(80 nm)/Ba(4 nm)/Al(120 nm),the device showed a maximal luminous efficiency (LE) of 13.5 cd A-1(corresponding to an external quantum efficiency (EQE) of 6.8%),and a peak power efficiency (PE) of 6.5 lm W-1 at 6.0 V.Meanwhile,the device exhibited pure white emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.34,0.35) at a current density of 12 mA cm-2,which is very close to the equi-energy white point with CIE coordinates of (0.33,0.33).The device performance can be further optimized when more balanced hole/electron injection is achieved by incorporating a lower conducting type anode buffer layer (PEDOT:PSS) and incorporating poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorenene)-alt-2,7-(9,9-dioctyfluorene)] (PFN) as an electron injection layer at the cathode.The optimized device showed an LE of 24.6 cd A-1 (with an EQE of 14.1%),while the peak power efficiency reached 12.66 lm W-1.Moreover,the WPLEDs showed good electroluminescence (EL) stability over a wide range of operating current density and luminance. 展开更多
关键词 white polymer light-emitting device phosphorescent iridium complex anode buffer layer water-/alcohol-soluble conjugated polymer
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Active Approach for Tamper Detection with Robustness to Lossy Compression
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作者 李剑 李生红 郑旭平 《Journal of Shanghai Jiaotong university(Science)》 EI 2013年第4期385-393,共9页
Active tamper detection using watermarking technique can localize the tampered area and recover the lost information. In this paper, we propose an approach that the watermark is robust to legitimate lossy compression,... Active tamper detection using watermarking technique can localize the tampered area and recover the lost information. In this paper, we propose an approach that the watermark is robust to legitimate lossy compression, fragile to malicious tampering and capable of recovery. We embed the watermark bits in the direct current value of energy concentration transform domain coefficients. Let the original watermark bits be content dependent and apply error correction coding to them before embedded to the image. While indicating the tam- pered area, the extracted bits from a suspicious image can be further decoded and then used to roughly recover the corresponding area. We also theoretically study the image quality and bit error rate. ExperimentM results demonstrate the effectiveness of the proposed scheme. 展开更多
关键词 active tamper detection energy concentration transform error correction code semi-fragile water- marking
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