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Determination of gross α and β activities in Zouma River based on online HPGe gamma measurement system

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Nuclear Science and Techniques 2020年第12期31卷 65-76页

作者： xian Guan Liang-Quan Ge Guo-Qiang zeng Xiao-Qin Deng Li-Peng Xu Sheng-Liang Guo Key Laboratory of Applied Nuclear Techniques in Geosciences of Sichuan Province Chengdu University of TechnologyChengdu 610059China Sichuan Management&Monitoring Center Station of Radioactive Environment Chengdu 610031China Chengdu New Nuclear Tyco Technology Co. LtdChengdu 610052China

This paper describes a low-cost and fast method to evaluate gross α and β^(-) radioactivities in natural water based on an online high-purity germanium detector gamma measurement *** major gamma activities in natural water are provided by natural and artificial radionuclides such as ^(40) K,^(137)Cs,and radionuclides belonging to ^(238)U and ^(232)Th *** main a emitters related to gamma emissions in natural water are ^(224)Ra(240.98 keV)and ^(226)Ra(186.21 keV),and the β^(-) emitters are ^(40) K(1460.85 keV),^(214)Bi(609.31 keV),^(208)Tl(583.19 keV),and ^(214)Pb(351.93 keV).The formula for gross α and β^(-) activity concentration is based on these radionuclides,and the short half-life decay products are considered in the *** detection efficiency of the device across energy region(0–3 MeV)is obtained through Monte Carlo simulation,and a calibration experiment is conducted to verify the simulation *** radioactivity is measured continuously for 114 d in Pixian County and Dongfeng Canal located in the Zouma River,Chengdu,Sichuan Province,China.A comparison of the calculation results and monitoring data from the Sichuan Management and Monitoring Center Station of Radioactive Environment indicates that the percentage and absolute error of a activity concentration is lower than 53%and 0.02 Bq/L,respectively,and that of β-activity concentration is lower than 33.2%and 0.016 Bq/L,*** method can rapidly determine gross α and β^(-) activity concentrations in natural water online.

关键词： Grossαandβ^(-)activity HPGe gamma spectrometer Online radioactivity level measurement for natural water Natural radioactivity Water sources of Chengdu

Spiro-fused bicyclo[3,2,2]octatriene-cored triptycene:synthesis,molecular packing,and functional aggregates

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Science China Chemistry 2021年第11期64卷 1976-1984页

作者： Qing Liu xian Chen Zhibiao Zhou Tingting Huang Yanpei Wang Sheng Xie Zebing zeng Ben Zhong Tang State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China Aggregation-Induced Emission(AIE)Institute Guangzhou Development DistrictHuangpuGuangzhou510530China Shenzhen Institute of Aggregate Science and Technology School of Science and EngineeringThe Chinese University of Hong KongShenzhen518172China

Aggregate science has led to the existence of functional properties at the aggregate level that significantly differs from those of corresponding single-molecule species,leading to a number of novel conceptual materials with state-dependent *** developing such materials,new molecular scaffolds that allow modulating the structural and functional properties of aggregates in a controlled manner could be extremely *** this study,we report a class of spiro-fused bicyclo[3,2,2]octatriene triptycene derivatives with a unique 3 D molecular scaffolding structure that displays aggregation-induced emission(AIE)activity with bright solid-state blue *** core scaffold features a Y-shaped bicyclo[3,2,2]octatriene backbone and a vertical crossover arrangement of adjacent spiro-conjugated *** classic bicyclo[2,2,2]octatrienes with high rigidity,this stereoscopic bicyclo[3,2,2]octatriene containing a seven-membered ring allows retaining certain flexibility in the molecular scaffold,which results in a weak fluorescence in dilute solutions(Φ_(F)<10%).However,the corresponding molecular aggregates emit intense fluorescence(Φ_(F)=50%-75%)and show prominent AIE activity because of the restriction of intramolecular scaffold ***,in principle,these stereoscopic scaffold constructions with partially restricted flexibility facilitate the assembly of multiple different crystalline packing structures in both porous and nonporous forms depending on the growth conditions of crystalline *** obtained crystals with regular voids(12.85×6.89Aeach)show reversible luminescence in response to the adsorption/desorption of iodine *** materials based on an unusual 3 D scaffold exhibit a high degree of structural modulation at the aggregate level and demonstrate potential applications in chemical sensing and flexible optoelectronics,which may open up the exploration of highly stereoscopic molecular building blocks for developing functi

关键词： aggregate science triptycene aggregation-induced emission organic porous material

Assessment of the macro-economic impacts of low-carbon road transportation policies in Chongqing,China

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Advances in Climate Change Research 2020年第4期11卷 429-441页

作者： TAN xian-Chun zeng Yuan GU Bai-He TANG Jie WANG Dong GUO Jian-Xin Institutes of Science and Development Chinese Academy of SciencesBeijing100190China School of Economics and Management Harbin Institute of TechnologyShenzhen518055China University of Chinese Academy of Sciences Beijing100190China

Reductions in the transportation sector's carbon dioxide emissions are increasingly of global *** one of the first low-carbon pilot and carbon trading pilot cities,and as one of the largest automobile production bases in China,Chongqing has multiple low-carbon transportation policies that are *** this study,three policy scenarios are set,including:1)improving the fuel economy of newly sold gasoline passenger cars to 5.71 per 100 km by 2020,2)promoting pure electric private cars to increase the share to 7% of private car sales by 2020,and 3)the policy mix scenario of the above two *** are undertaken with the Chinese Academy of Sciences general equilibrium(CAS-GE)model,a type of computable GE model,to assess the macro-economic impact and the industrial impact of the three policy *** the policy impact mechanism analysis and data-mapping process,the micro-economic impact analysis results,including costs and fuel savings,for the two policies from the bottom-up model are taken as the shock variables and inputs for the CAS-GE *** results show that:1)the two policies will both have a slightly negative impact(-0.09% and -0.30%)on Chongqing's GDP in 2020;2)the employment rate will decrease by 0.12% and 0.47%,but the inflation rate will be restrained to a certain extent(-0.21% and -0.17%);and 3)the complementarity of the mixed policy can weaken the negative impact of the two policies when implemented *** mixed policy will reduce the GDP slightly by 0.37%,compared with the cumulative effect of the two policies implemented separately,resulting in cost-effective synergies at the macroeconomic impact level;and 4)the COVID-19 pandemic in 2020 has an uncertain impact on the *** method and results can provide a reference for the formulation and adjustment of low-carbon transportation policies in other large cities.

关键词： Low-carbon road transportation policies Policy impact mechanism Macro-economic impact modeling Mixed policy analysis Chongqing

A distributed Grid-Xinanjiang model with integration of subgrid variability of soil storage capacity

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Water Science and Engineering 2016年第2期9卷 97-105页

作者： Wei-jian Guo Chuan-hai Wang Teng-fei Ma xian-min zeng Hai Yang PowerChina Huadong Engineering Corporation Limited Hangzhou 311122 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of Hydrology and Water Resources Hohai University Nanjing 210098 China

Realistic hydrological response is sensitive to the spatial variability of landscape properties. For a grid-based distributed rainfall-runoff model with a hypothesis of a uniform grid, the high-frequency information within a grid cell will be gradually lost as the resolution of the digital elevation model(DEM) grows coarser. Therefore, the performance of a hydrological model is usually scale-dependent. This study used the GridXinanjiang(GXAJ) model as an example to investigate the effects of subgrid variability on hydrological response at different scales. With the aim of producing a more reasonable hydrological response and spatial description of the landscape properties, a new distributed rainfall-runoff model integrating the subgrid variability(the GXAJSV model) was developed. In this model, the topographic index is used as an auxiliary variable correlated with the soil storage capacity. The incomplete beta distribution is suggested for simulating the probability distribution of the soil storage capacity within the raster grid. The Yaogu Basin in China was selected for model calibration and validation at different spatial *** demonstrated that the proposed model can effectively eliminate the scale dependence of the GXAJ model and produce a more reasonable hydrological response.

关键词： Scale effect Subgrid variability Soil storage capacity Incomplete beta distribution GXAJSV model

A new triterpenoid saponin from the leaves and stems of Panax quinquefolium L.

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Chinese Chemical Letters 2009年第10期20卷 1207-1210页

作者： Guo Yu Li Yi Mei zeng He Meng xian Li Jin Hui Wang School of Pharmacy Shihezi University Shihezi 832002 China School of Traditional Chinese Materia Medica. Shenyang Pharmaceutical University Shenyang 110016 China

One new triterpcnoid saponin, quinquenoside L17 （1）, was isolated from the leaves and stems of Panax quinquefolium L., and its structure was elucidated as 20-O-[（β-D-xylopyranosyl-（1-6）-O-β-D-glucopyranosy）]-6-O-β-D-glucopyranosy1-dammar-24-ene- 3,6,12,20-tetraol, by the combination analysis of one-dimensional NMR and two-dimensional NMR, mass spectrometry, CD spectrum and chemical evidences.

关键词： Panax quinquefolium L. Quinquenoside L17 Triterpenoid saponin

Long-and Short-Term Self-Learning Models of Rolling Force in Rolling Process Without Gaugemeter of Plate

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Journal of Iron and Steel Research International 2009年第1期16卷 27-31,61页

作者： ZHU Fu-wen zeng Qing-liang HU xian-lei LI Xi-an LIU xiang-hua The State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004Liaoning China The Second Plant of Plate Anyang Steel Co Ltd Anyang 455004 Henan China

Owing to a lack of gaugemeter and the variety of steel grades and standards in some plate mills, the longand short-term self-learning models of rolling force based on gauge soft-measuring with high precision were brought up. The soft-measuring method and target value locked method were used in these models to confirm the actual exit gauge of passes, and thick layer division and exponential smoothing method were used to dispose the deformation resistance parameter, which could be calculated from the actual data of the rolling process. The correlative mathematical methods can also be adapted to self-learning with gaugemeter. The models were applied to the process control system of AGC （automatic gauge control） reconstruction on 2800 mm finishing mill of Anyang steel and favorable effect was obtained.

关键词： plate self-learning soft measuring rolling force

Comparative Study of Intrachain versus Interchain Cross-linking on the Mechanical,Thermal and Dielectric Properties of Low-k Polyimide

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Chinese Journal of Polymer Science 2024年第11期42卷 1824-1834,I0014页

作者： Wan-Jing Zhao Yi-Zhang Tong Pei-Pei zeng Yang-Sheng Zhou xian-Wu Cao Wei Wu National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing Engineering of Ministry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640China Engineering Center for Superlubricity Jihua LaboratoryFoshan528200China Guangdong Provincial Key Laboratory of Distributed Energy Systems Guangdong Provincial Engineering Research Center of Distributed Energy SystemsDongguan University of TechnologyDongguan523808China

Polyimide(PI)is widely used in high-frequency communication technology due to its exceptional comprehensive ***,traditional PI has a relatively elevated dielectric constant and dielectric ***,the different cross-linked structures were introduced in PI matrix and conducted a detailed discussion on the influence of cross-linking agent content and cross-linking structure type on the overall performance of PI *** comparison to the dielectric constant of 2.9 of neat PI,PI with an interchain cross-linking structure containing 2 wt%1,3,5-tris(4-aminophenyl)benzene(TAPB)(interchain-PI-2)exhibited the reduced dielectric constant of 2.55 at 1 *** PI films with intrachain crosslinking structure containing 2 wt%TAPB(intrachain-PI-2)exhibited the lowest dielectric constant of 2.35 and the minimum dielectric loss of0.0075 at 1 *** was due to the more entanglement junctions of intrachain-PI resulting in decreased carrier *** thermal expansion coefficients of both interchain-PI and intrachain-PI films were effectively ***,in contrast to interchain-PI films,the intrachain-PI films maintained colorlessness and transparency as the cross-linking agent content *** work compared the effects of two different cross-linked structures on the performance of PI films and provided a feasible way to obtain low-k PI films with excellent comprehensive performance for 5G applications.

关键词： Interchain cross-linking Intrachain cross-linking Polyimide Low dielectric

Effect of Annealing Temperature on the Shape Memory Properties of Cold-Rolled Dual-Phase Ni-Mn-Ga-Gd Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第11期28卷 1403-1406页

作者： Xin Zhang Qing-Suo Liu xian-Shun zeng Jie-He Sui Wei Cai Ai-Lian Liu School of Materials Science and Engineering Tianjin University of Technology National Key Laboratory Precision Hot Processing of Metals Harbin Institute of Technology College of Material Science and Engineering Heilongjiang University of Science and Technology

The influence of annealing temperature on the shape memory effect （SME） and recovery ratio of cold-rolled dual-phase Ni58Mn25Ga16.9Gdo.1 high-temperature shape memory alloy were investigated. The results showed that the SME can be improved by appropriate annealing. SME of 6.0% and recovery ratio of 98% were observed in the rolled alloy at 550 ℃ annealing, which were larger than that of the samples annealed at other temperatures. The annealing temperature was in between the recrystallization temperatures of the martensite and 7 phase, which leads to the work-hardening state of 7 phase kept unchanged during annealing process, and therefore, the critical slip stress of y phase increased. Thus, the plastic deformation of ~ phase reduced during the compression process, and the SME increased.

关键词： Shape memory alloys Recrystallization Cold rolling Ni-Mn-Ga

Migration and risks of potentially toxic elements from sewage sludge applied to acid forest soil

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Journal of Forestry Research 2023年第6期34卷 2011-2026页

作者： Shuangshuang Chu Lihua xian Can Lai Wenjun Yang Jing Wang Mandi Long Jianhui Ouyang Dandan Liao Shucai zeng School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275People’s Republic of China College of Forestry and Landscape Architecture South China Agricultural UniversityGuangzhou 510642People’s Republic of China College of Horticulture and Landscape Architecture Zhongkai University of Agriculture and EngineeringGuangzhou 510225People’s Republic of China College of Life Sciences Guizhou UniversityGuiyang 550025People’s Republic of China

`The application of sewage sludge(SS)to forested lands may lead to the downward migration of potentially toxic elements(PTEs)through rainfall and thus pose risk to the subsoil and *** column experiments were conducted using leaching water equivalent to the rainfall amount in the study area over 3 years to investigate changes in concentrations of PTEs,including copper(Cu),zinc(Zn),lead(Pb),cadmium(Cd),and nickel(Ni)in the leachate from the acidic forest *** quality index of leachate,potential ecological risk and human health risk in soil at different leaching stages were *** sludge was applied at SS/soil mass ratios of 0:100(controls),15:85(T1),30:70(T2),45:55(T3),60:40(T4),and 75:25(T5).All treatments resulted in increased PTEs concentration in the upper 20 cm soil,T3-T5 increased potential ecological risk from"low"(control)to"moderate"or"considerable".During first year leaching,PTEs concentration increased with increasing SS/soil ratios,but the water quality index of T1-T3 was"excellent"or"good".Pb,Cu,Cd,and Ni in the 20-40 cm soil depth,and Zn in the 60-80 cm soil depth were also enriched,but potential ecological risk was"low".In subsequent leaching,PTEs concentration of leachate gradually returned to the background value and water quality index was"excellent".There were no significant changes in PTEs and ecological risk *** the monitoring process,the health risk caused by the migration of PTEs to the human body was always within the acceptable ***,this study provides a reference for the management of risks from the application of SS on forestlands,i.e.,SS/soil ratios<45:55 is recommended on forestlands,and special attention should be given to early leaching *** addition,it also provides an important assessment method for the risk of PTEs leaching and migration in forested land application.

关键词： Water quality Soil column Rainfall simulation Risk assessment Forest management