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Recent development in fluorescent probes based on attacking of double bond and masking of functional group

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Chinese Chemical Letters 2022年第6期33卷 2765-2772页

作者： Nadeem Ahmed Wajeeha Zareen yong ye Phosphorus Chemical Engineering Research Center of Henan Province The College of ChemistryZhengzhou UniversityZhengzhou 450002China

The works on the procedure of fluorescent sensors for the detection of biological analytes are extremely *** diverse analytical approaches,fluorescence is the most eye-catching due to its high sensitivity,selectivity,rapidity,robustness,ease of measurement and non-destructive ***,we show different fluorescent probes synthesized for estimation and detection of biological analytes(H_(2)S,SO_(3)^(2-)/HSO_(3)^(-),H_(2)O_(2),HOCl,HNO,ONOO^(-)).These probes were constructed by masking the functional groups (hydroxyl and amino) of fluorophore and formation of active C=C,C=N,C=O and N=N for specific *** this review we concentrate on synthesis of the probe,their photophysical properties and applications to biological studies.

关键词： Fluorescent probes Hypochlorous acid Peroxynitirite Biothiols Michael addition

Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

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Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming Xia yong-Jun ye Shu-Yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the *** these measurement methods,the closed-loop method is frequently ***,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation *** CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and *** this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the *** consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was *** effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were *** on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion *** CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

Liquid crystal of nanocellulose whiskers' grafted with acrylamide

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Chinese Chemical Letters 2012年第3期23卷 367-370页

作者： Jie Yang Dai yong ye School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China

12%acrylamide（AM） was grafted onto the surface of nanocellulose whiskers（NCW）,which was self-assembled to be the chiral nematic suspension at 3%*** acrylamide grafted NCW（AM-g-NCW） was characterized with Fourier Transform Infrared Spectroscopy（FTIR）.The grafting ratio was measured by elemental *** degrees of crystallinity of the AM-g-NCW were measured by X-ray diffraction（XRD）.The liquid crystalline properties of the AM-g-NCW were investigated by the polarizing optical microscopy（POM）.The AM-g-NCW was found to self-assembly to be a lyotropic state.

关键词： Nanocellulose whiskers Acrylamide Surface grafting Liquid crystal

Soil Organic Carbon Content and Distribution in a Small Landscape of Dongguan, South China

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Pedosphere 2006年第1期16卷 10-17页

作者： SU Zhi-Yao XIONG yong-Mei ZHU Jian-Yun ye yong-Chang ye Mai College of Forestry South China Agricultural University Wushan Guangzhou 510642 （China） Dongguan Research Institute of Forestry Dongguan 511700 （China）

Global warming has become an increasing concern, and using soil as a carbon sink to sequester carbon dioxide has attracted much attention in recent years. In this study, soil organic carbon (SOC) content and organic carbon density were estimated based on a soil survey of a small landscape in Dongguan, South China, with spatial heterogeneity of SOC distribution and the impacts of land-use patterns on soil organic carbon content assessed. Field sampling was carried out based on a 150 m×150 m grid system overlaid on the topographic map of the study area and samples were collected in three 20-cm layers to a depth of 60 cm. Spatial variability in the distribution of SOC was assessed using the Kruskal-Wallis test. Results showed that SOC in the topsoil layer (0-20 cm) was not much higher or even lower in some sites than the underlying layers, and except for the two sites covered with natural woodland, it did not exhibit a pronounced vertical gradient. The difference in both horizontal and vertical distribution of SOC was not statistically significant. However, in the topsoil layer among land-use/land-cover patterns, significant differences (P≤0.05) in SOC distribution existed, indicating that management practices had great impact on SOC content. SOC storage in the study area to a depth of 20, 40, and 60 cm was estimated as 2.13×106 kg, 3.46×106 kg, and 4.61×106 kg, respectively.

关键词： land-use pattern organic carbon content organic carbon density spatial wariability

Super-Resolution Imaging by using a Metallic Rod Array in the Near Infrared Region

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Chinese Physics Letters 2012年第4期29卷 210-212页

作者： YAO Jie ye yong-Hong College of Physics Science and Technology Nanjing Normal UniversityNanjing 210046

An array of metallic rods can transport details below the diffraction limit of an object from the front face to the back *** super-resolution imaging system has been studied in the microwave,mid-infrared and optical *** investigate its performance in the near infrared (1550nm) *** simulations show that the near-field components of dipole sources are transferred by the excitation and propagation of the surface plasmon mode of the *** appropriate length of rods is determined by the excited surface plasmon *** spatial resolution is greatly affected by the loss of metal.

关键词： resolution Infrared details

Effect of Cold Rolling Parameters on the Longitudinal Residual Stress Distribution of GH4169 Alloy Sheet

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1510-1517页

作者： Neng-yong ye Ming Cheng Shi-Hong Zhang Institute of Metal Research Chinese Academy of Sciences

For plastic deformed parts, the dimensional accuracy is significantly affected by residual stresses and so does the performance in service. Therefore, the rolling process of GH4169 alloy sheet at room temperature was investigated by finite element method. The effects of rolling reduction, friction coefficient, rolling velocity and initial stress on the longitudinal residual stress distribution over the thickness of GH4169 alloy sheet were analyzed. The results show that the values of longitudinal residual stress can be slightly reduced by increasing the rolling reduction and velocity. The longitudinal residual stress over the thickness distributes as ‘‘V＇＇ type or weak ‘‘W＇＇ type. The initial stress mainly has an effect on the longitudinal stress in the backward slip area. But the friction coefficient has remarkable influence on longitudinal residual stress. With the friction coefficient increasing from 0.1 to 0.5, the value of longitudinal residual stress on the sheet surface is reduced by 282 MPa. Simultaneously, the tensile stress turns into compressive stress with a strong‘‘W＇＇ type distribution.

关键词： GH4169 alloy Cold rolling Residual stress Process parameters

SCHEDULING ALGORITHM BASED ON FOLLOW-UP SHARING CHARACTER FOR POST-EVENT RESPONSE RESOURCE DISTRIBUTION IN LARGE-SCAL DISASTERS

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Journal of Systems Science and Systems Engineering 2016年第1期25卷 77-101页

作者： yong ye Nan Liu Guiping Hu Shalei Zhan Department of Management College of Humanities and Management Wenzhou Medical University Wenzhou 325035 P.R. China Department of Management Sciences & Engineering School of Management Zhejiang University Hangzhou 310058 P.R. China Industrial and Manufacturing Systems Engineering 3014 Black Engineering Iowa State University Ames IA 50011 School of Computer Science and Information Engineering Zhejiang Gongshang University Hangzhou 310058 P.R. China

Post-event response planners must develop effective and efficient plans for the proper allocation and distribution of resources to impacted areas （IAs） within a critical time window. To determine the effectiveness and efficiency of distribution plans, this study addresses resource allocation effectiveness losses （RAEL, or losses caused by the mismatch between supply and demand in IAs） and emergency logistics time costs （ELTC, or transportation time of logistics processes under emergency conditions）. Moreover, this study examines a follow-up sharing character （FSC） that coordinates resources among different phases. This research proposes an integrated model （IM） based on this character. This model aims to minimize RAEL and ELTC. Furthermore, the IM combines the time dimension model （TDM）, which coordinates the demands and supplies of all phases in the planning horizon, and the space dimension model （SDM）, which generates a specific distribution plan for the first phase. An analytical solution is obtained for the TDM as per the definition of FSC, after which the SDM is solved through a single-objective linear programming model. After solving the IM effectively, we fred that the proposed methodology fits the emergency circumstance well. Insights derived from the model are also presented in the conclusion.）

关键词： Emergency management humanitarian logistics decision-making resource distribution

Soil Respiration in a Subtropical Mangrove Wetland in the Jiulong River Estuary, China

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Pedosphere 2013年第5期23卷 678-685页

作者： JIN Liang LU Chang-Yi ye yong ye Gong-Fu College of the Environment & Ecology Xiamen University Xiamen University Tan Kah Kee College Fujian Institute of Forestry Science

The diurnal and seasonal variations of soil respiration （SR） were studied at a subtropical mangrove wetland in the Jiulong River Estuary from May 2010 to April 2011. SR rates were measured continuously from 08：00 to 06：00 local time （24-h time system） on July 8-9 and October 3-4, 2010; and January 15-16 and April 11-12, 2011. Similar patterns in the diurnal variation of SR were observed on October 2-3 and April 11-12, with the maximum values at 14：00 and the minimum at 00：00. However, the diurnal dynamics of SR on July 8-9, 2010 and January 15-16, 2011 showed different patterns, with the maximum values at 08：00-10：00 on above sampling dates and the minimum at 22：00 on July 8 and at 04：00 on January 16. The daily mean values of SR approximated to the values measured at 08：00. SR fluctuated with distinct seasonal patterns. The seasonal variation was characterized by a mono-peak pattern, with the highest rate （6.18 ~mol CO2 m-2 s-1） in July and the lowest rate （0.36 ~tmol CO2 m-2 s-1） in December. The results showed that the variation of SR in mangrove wetland was mainly controlled by soil temperature, and there was no significant correlation between SR and soil water content. It also implied that the model of SR in mangrove wetland should not only consider the effect of soil temperature, but also incorporate other factors, such as water level, precipitation, microbial activity and photosynthesis, which also could affect SR.

关键词： controlling factors Kandelia candel microbial activity neap tide soil temperature

Blind channel identication of nonlinear folding mixing model

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Journal of Systems Engineering and Electronics 2006年第3期17卷 509-512页

作者： Su yong Xu Shangzhi ye Zhongfu Inst. of Statistical Signal Processing Dept. of Electronic Engineering and Information Science Univ. of Science and Technology of China Hefei 230027 P. R. China

Signals from multi-sensor systems are often mixtures of （statistically） independent sources by unknown mixing method. Blind source separation（BSS） and independent component analysis（ICA） are the methods to identify/recover the channels and the sources. BSS/ICA of nonlinear mixing models are difficult problems. For instance, the post-nonlinear model has been studied by several authors. It is noticed that in most cases, the proposed models are always with an invertible mixing. According to this fact there is an interesting question, how about the situation of the non-invertible non-linear mixing in BSS or ICA？ A new simple non-linear mixing model is proposed with a kind of non-invertible mixing, the folding mixing, and method to identify its channel, blindly.

关键词： blind channel identication non-linear mixing non-invertible.