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Changes in spatial variations of sap flow in Korean pine trees due to environmental factors and their effects on estimates of stand transpiration 被引量:2
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作者 Minkyu MOON Taek-yu KIM +4 位作者 Juhan PARK Sungsik CHO Daun RYU Sanguk SUH Hyun Seok KIM 《Journal of Mountain Science》 SCIE CSCD 2016年第6期1024-1034,共11页
It is difficult to scale up measurements of the sap flux density(J_S) for the characterization of tree or stand transpiration(E) due to spatial variations in J_S and their temporal changes.To assess spatial variations... It is difficult to scale up measurements of the sap flux density(J_S) for the characterization of tree or stand transpiration(E) due to spatial variations in J_S and their temporal changes.To assess spatial variations in the sap flux density of Korean pine(Pinus koraiensis) and their effects on E estimates,we measured the J_S using Granier-type sensors.Within trees,the J_S decreased exponentially with the radial depth,and the J_S of the east aspects were higher than those of the west aspects.Among trees,there was a positive relationship between J_S and the tree diameter at breast height,and this positive relationship became stronger as the transpiration demand increased.The spatial variations that caused large errors in E estimates(i.e.,up to 110.8 % when radial variation was ignored) had varied systematically with environmental factors systematic characteristics in relation to environmental factors.However,changes in these variations did not generate substantial errors in the E estimates.For our study periods,the differences in the daily E(E_D) calculated by ignoring radial,azimuthal and tree-to-tree variations and the measured E_D were fairly constant,especially when the daily vapor pressure deficit(D_D)was higher than 0.6 k Pa.These results imply that the effect of spatial variations changes on sap flow can be a minor source of error compared with spatial variations(radial,azimuthal and tree-to-tree variations) when considering E estimates. 展开更多
关键词 Sap flow Environmental factors Pinuskoraiensis Scale-up Stand transpiration
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Study on the Post-evaluation of Environmental Planning Based on Logical Framework Approach 被引量:2
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作者 CHEN Yu-xian DONG Ze-qin 《Meteorological and Environmental Research》 CAS 2011年第2期1-5,9,共6页
[Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province fo... [Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province for example, by means of logical framework approach (LFA), the post-evaluation on environmental planning was carried out from the aspects of evaluation content, index system, implementation steps, evaluation feedback and input-output analysis of environmental planning. [Result] The post-evaluation on environmental planning by means of LFA achieved expected purpose and various indexes at different stages of environmental planning was assessed, and then corresponding countermeasures were put forward according to the problems which were found by problem tree of environmental planning project. [Conclusion] The study could provide theoretical references for the post-evaluation on environmental planning in future. 展开更多
关键词 Logical framework approach Environmental planning during '11th Five-year Plan' POST-EVALUATION China
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Systematic engineering of BiVO_(4)photoanode for efficient photoelectrochemical water oxidation
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作者 Zhiting Liang Meng Li +6 位作者 Kai‐Hang Ye Tongxin Tang Zhan Lin Yuying Zheng Yongchao Huang Hongbing Ji Shanqing Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期12-21,共10页
BiVO_(4)is one of the most promising photoanode materials for photoelectrochemical(PEC)solar energy conversion,but it still suffers from poor photocurrent density due to insufficient light‐harvesting efficiency(LHE),... BiVO_(4)is one of the most promising photoanode materials for photoelectrochemical(PEC)solar energy conversion,but it still suffers from poor photocurrent density due to insufficient light‐harvesting efficiency(LHE),weak photogenerated charge separation efficiency(Φ_(Sep)),and low water oxidation efficiency(Φ_(OX)).Herein,we tackle these challenges of the BiVO_(4)photoanodes using systematic engineering,including catalysis engineering,bandgap engineering,and morphology engineering.In particular,we deposit a NiCoO_(x)layer onto the BiVO_(4)photoanode as the oxygen evolution catalyst to enhance theΦ_(OX)of Fe‐g‐C_(3)N_(4)/BiVO_(4)for PEC water oxidation,and incorporate Fe‐doped graphite‐phase C_(3)N_(4)(Fe‐g‐C_(3)N_(4))into the BiVO_(4)photoanode to optimize the bandgap and surface areas to subsequently expand the light absorption range of the photoanode from 530 to 690 nm,increase the LHE andΦ_(Sep),and further improve the oxygen evolution reaction activity of the NiCoO_(x)catalytic layer.Consequently,the maximum photocurrent density of the as‐prepared NiCoO_(x)/Fe‐g‐C_(3)N_(4)/BiVO_(4)is remarkably boosted from 4.6 to 7.4 mA cm^(−2).This work suggests that the proposed systematic engineering strategy is exceptionally promising for improving LHE,Φ_(Sep),andΦ_(OX)of BiVO_(4)‐based photoanodes,which will substantially benefit the design,preparation,and large‐scale application of next‐generation high‐performance photoanodes. 展开更多
关键词 bismuth vanadate carbon nitride charge separation HETEROJUNCTION water oxidation
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Degradation of Synthetic Dyeing Wastewater by Underwater Electrical Discharge Processes 被引量:4
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作者 S.D.KIM D.I.JANG +2 位作者 B.J.LIM S.B.LEE Y.S.MOK 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第7期659-665,共7页
Electrical discharge treatments of synthetic dyeing wastewater were carried out with two different systems: underwater pulsed electrical discharge (UPED) and underwater dielectric barrier discharge (UDBD). Reacti... Electrical discharge treatments of synthetic dyeing wastewater were carried out with two different systems: underwater pulsed electrical discharge (UPED) and underwater dielectric barrier discharge (UDBD). Reactive Blue 4 (RB4) and Acid Red 4 (AR4) were used as model contaminants for the synthetic wastewater. The performance of the aforementioned systems was compared with respect to the chromaticity removal and the energy requirement. The results showed that the present electrical discharge systems were very effective for degradation of the dyes. The dependences of the dye degradation rate on treatment time, initial dye concentration, electrical energy, and the type of working gas including air, 02, and N2 were examined. The change in the initial dye concentration did not largely affect the degradation of either RB4 or AR4. The energy delivered to the UPED system was only partially utilized for generating reactive species capable of degrading the dyes, leading to higher energy requirement than the UDBD system. Among the working gases, the best performance was observed with O2. As the degradation proceeded, the concentration of total dissolved solids and the solution conductivity kept increasing while pH showed a decreasing trend, revealing that the dyes were effectively mineralized. 展开更多
关键词 DEGRADATION dyeing wastewater pulsed electrical discharge dielectric barrierdischarge
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Unveiling the promotion of accelerated water dissociation kinetics on the hydrogen evolution catalysis of NiMoO_(4) nanorods 被引量:5
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作者 Tuzhi Xiong Bowen Huang +7 位作者 Jingjing Wei Xincheng Yao Ran Xiao Zhixiao Zhu Fang Yang Yongchao Huang Hao Yang M.-Sadeeq(Jie Tang)Balogun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期805-813,共9页
Nickel molybdate(NiMoO_(4))attracts superior hydrogen desorption behavior but noticeably poor for efficiently driving the hydrogen evolution reaction(HER)in alkaline media due to the sluggish water dissociation step.H... Nickel molybdate(NiMoO_(4))attracts superior hydrogen desorption behavior but noticeably poor for efficiently driving the hydrogen evolution reaction(HER)in alkaline media due to the sluggish water dissociation step.Herein,we successfully accelerate the water dissociation kinetics of NiMoO_(4)for prominent HER catalytic properties via simultaneous in situ interfacial engineering with molybdenum dioxide(MoO_(2))and doping with phosphorus(P).The as-synthesized P-doped NiMoO_(4)/MoO_(2)heterostructure nanorods exhibit outstanding HER performance with an extraordinary low overpotential of-23 m V at a current density of 10 m A cm^(-2),which is highly comparable to the performance of the state-of-art Pt/C coated on nickel foam(NF)catalyst.The density functional theory(DFT)analysis reveals the enhanced performance is attributed to the formation of MoO_(2)during the in situ epitaxial growth that substantially reduces the energy barrier of the Volmer pathway,and the introduction of P that provides efficient hydrogen desorption of Ni MoO_(2).This present work creates valuable insight into the utilization of interfacial and doping systems for hydrogen evolution catalysis and beyond. 展开更多
关键词 NiMoO_(4)/MoO_(2) Water dissociation kinetics Interfacial and doping Density functional theory Hydrogen evolution reaction
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Spatial Ecology of Translocated and Resident Amur Ratsnakes(Elaphe schrenckii) in Two Mountain Valleys of South Korea 被引量:1
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作者 Jung-Hyun LEE Daesik PARK 《Asian Herpetological Research》 SCIE 2011年第4期223-229,共7页
The translocation of snakes has been viewed as a useful tool to augment declining populations and to mitigate human-wildlife conflicts, even though released snakes often exhibit relatively high mortality. We radio-tra... The translocation of snakes has been viewed as a useful tool to augment declining populations and to mitigate human-wildlife conflicts, even though released snakes often exhibit relatively high mortality. We radio-tracked 13 Amur Ratsnakes (Elaphe schrenckii) in the Woraksan National Park in South Korea from July 2008 to May 2009. Two of these snakes were residents, and 11 had been illegally captured in areas remote from the study site and were donated by the park office. During the study period, six of the translocated snakes were lost: two were killed by predators, one died of unknown causes, and the radio signals of three of the snakes were lost. In the field, the ratsnakes laid eggs in early August, moved into hibemacula in late November, and moved away from the hibemacula in mid-April. Compared to the resident snakes, five of the translocated snakes traveled approximately 1.3 times farther per week, and the home ranges of the translocated snakes were three to six times larger than those of the resident snakes. In addition, the translocated snakes were found underground more frequently than the resident snakes. The management recommendations resulting from this study will guide biologists and land use managers in making appropriate decisions regarding release sites and the use of gravid females in the translocation of this endangered ratsnake. 展开更多
关键词 Amur Ratsnake conservation Elaphe schrenckii RADIOTELEMETRY TRANSLOCATION
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Evaluation of Accuracy and Precision of IRMS by Using Standard Materials and Applications 被引量:1
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作者 J. Y. Hwang B. K. Kim +3 位作者 M. S. Kim J. W. Choi T. S. Kim W. S. Lee 《Journal of Agricultural Chemistry and Environment》 2016年第4期211-222,共13页
The isotope ratio mass spectrometer (IRMS) is an instrument that measures both of the elemental contents and isotope ratios of hydrogen, oxygen, carbon, nitrogen and sulfur in environmental samples at the same time. I... The isotope ratio mass spectrometer (IRMS) is an instrument that measures both of the elemental contents and isotope ratios of hydrogen, oxygen, carbon, nitrogen and sulfur in environmental samples at the same time. In this study, we want to try to get two main goals;first, to make up for setting the analytical conditions such as accuracy and precision, second, to apply for comparing of the carbon and nitrogen isotope ratio of sediments in the abandoned mine located in middle province of Korea. For the first goal, a recently introduced IRMS was used to analyze CRM (certified reference materials), which helped to make up the analytical conditions of carbon and nitrogen isotope ratios. So, the accuracy and precision of isotope ratios and elemental contents were also assessed simultaneously, and also the results were very satisfactory. The analytical results of carbon reference materials (EMA-P2) showed an accuracy of -2.801 × 10‰ ± 0.01‰ (2σ) and a precision of 0.009‰ in the mass range from 0.008 μg - 0.162 μg. For nitrogen reference materials (EMA-P2), an accuracy of -1.632‰ ± 0.72‰ (2σ) was obtained in the mass range from 0.082 - 0.162 mg. These values of accuracy and precision are higher than those reported by other studies. For the second goal, carbon and nitrogen isotopes in river sediment near abandoned mines were analyzed based on the established analytical conditions. The result suggested that carbon isotope ratios ranged from -22.5‰ - -7.5‰ and nitrogen isotope ratios from -1.9‰ - 7.9‰. By comparing the isotope ratios and sampling sites of sediment, we know that the nitrogen isotope values in samples of entrance area of mine are greater than those of the farm house area, which is indicating the effects of organic materials. So, we could guess that the newly accumulated organic materials were much more in the farm house area than mine entrance area. And a result of this study, the accuracy and precision tests of IRMS using certified reference materials were very satisfactory and optimum analytical conditions were established well. And also, it was found that the applications of isotopic analysis for environmental samples by using the IRMS could be very useful for the studies on tracing pollution sources. 展开更多
关键词 Stable Isotope Carbon Isotope Nitrogen Isotope PRECISION ACCURACY
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The carbon fluxes in different successional stages:modelling the dynamics of tropical montane forests in South Ecuador 被引量:1
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作者 sebastian paulick claudia dislich +2 位作者 jürgen homeier rico fischer andreas huth 《Forest Ecosystems》 SCIE CSCD 2017年第2期143-153,共11页
Background: Tropical forests play an important role in the global carbon(C) cycle.However, tropical montane forests have been studied less than tropical lowland forests, and their role in carbon storage is not well... Background: Tropical forests play an important role in the global carbon(C) cycle.However, tropical montane forests have been studied less than tropical lowland forests, and their role in carbon storage is not well understood.Montane forests are highly endangered due to logging, land-use and climate change.Our objective was to analyse how the carbon balance changes during forest succession.Methods: In this study, we used a method to estimate local carbon balances that combined forest inventory data with process-based forest models.We utilised such a forest model to study the carbon balance of a tropical montane forest in South Ecuador, comparing two topographical slope positions(ravines and lower slopes vs upper slopes and ridges).Results: The simulation results showed that the forest acts as a carbon sink with a maximum net ecosystem exchange(NEE) of 9.3 Mg C?(ha?yr)-1during its early successional stage(0–100 years).In the late successional stage, the simulated NEE fluctuated around zero and had a variation of 0.77 Mg C?(ha?yr)–1.The simulated variability of the NEE was within the range of the field data.We discovered several forest attributes(e.g., basal area or the relative amount of pioneer trees) that can serve as predictors for NEE for young forest stands(0–100 years) but not for those in the late successional stage(500–1,000 years).In case of young forest stands these correlations are high, especially between stand basal area and NEE.Conclusion: In this study, we used an Ecuadorian study site as an example of how to successfully link a forest model with forest inventory data, for estimating stem-diameter distributions, biomass and aboveground net primary productivity.To conclude, this study shows that process-based forest models can be used to investigate the carbon balance of tropical montane forests.With this model it is possible to find hidden relationships between forest attributes and forest carbon fluxes.These relationships promote a better understanding of the role of tropical montane forests in the context of global carbon cycle, which in future will become more relevant to a society under global change. 展开更多
关键词 Forest model Tropical montane forest Forest succession Carbon balance Forest productivity FORMIND
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Calculation of Intercepted Volume of Sewer Overflows: a Model for Control of Nonpoint Pollution Sources in Urban Areas
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作者 S. C. Choi D. I. Jung +1 位作者 C. H. Won J. M. Rim 《Journal of Ocean University of China》 SCIE CAS 2006年第4期317-321,共5页
The authors discovered large differences in the characteristics of overflows by the calculation of 1) intercepting volume of overflows for sewer systems using SWMM model which takes into consideration the runoff and ... The authors discovered large differences in the characteristics of overflows by the calculation of 1) intercepting volume of overflows for sewer systems using SWMM model which takes into consideration the runoff and pollutants from rainfalls and 2) the intercepted volume in the total flow at an investigation site. The intercepting rate at the investigation point of CSOs showed higher values than the SSDs. Based on the modeling of the receiving water quality after calculating the intercepting amount of overflows by considering the characteristics of outflows for a proper management of the overflow of sewer systems with rainfalls, it is clear that the BOD decreased by 82.9%-94.0% for the discharge after intercepting a specific amount of flows compared to the discharge from unprocessed overflows. 展开更多
关键词 nonpoint pollution sources CSOS SSDs SWMM intercepted volume
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An Assessment Study of Usefulness of Using Olive (<i>Olea europaea</i>L.) Leaves in Biomonitoring the Air Pollution near Baniyas Oil Refinery, Syria: Estimating of Total Phenolic Compounds and Lead, Copper and Manganese in Olive Leaves
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作者 Abeer Mahfoud Kamel Khalil Chahid Moustapha 《American Journal of Plant Sciences》 2018年第12期2514-2531,共18页
The aim of this study was to estimate the total amount of phenolic compounds of olive trees leaves (Olea europaea L.) as a biomarker for the assessment of heavy metals (HMs) air pollution (Pb, Cu and Mn) in Baniyas ar... The aim of this study was to estimate the total amount of phenolic compounds of olive trees leaves (Olea europaea L.) as a biomarker for the assessment of heavy metals (HMs) air pollution (Pb, Cu and Mn) in Baniyas area. Olive trees were selected as the predominant species in the study area. Samples were collected from 6 locations at different distances from the vicinity of Baniyas refinery (0.1, 0.5, 2, 4, 6, 10) Km. The control was taken from an area about 20 km from the refinery to the north-east (Al-Qardaha rural). The concentration of total phenolic compounds (TPC) during the summer was (45.6 - 70.85) mg GAE/g dw, and during winter (35.6 - 52.9) mg GAE/g dw. The concentrations of the studied HMs (Pb, Cu and Mn) in unwashed leaves during summer were (0.879 - 2.170) ppm, (0.75 - 5.21) ppm and (54.38 - 8.78) ppm respectively, whilst during the winter concentrations were (0.479 - 1.023) ppm, (1.54 - 7.29) ppm and (53.79 - 7.58) ppm respectively. The results showed significant differences in the concentration of total phenolic compounds and HMs (Pb, Cu and Mn) between sites (ANOVA), significant differences in concentrations of both total phenols and HMs (Pb and Cu) between summer and winter at all sites (t-test, p < 0.05). TPC, Pb and Mn were higher in summer in all sites than in winter. Levels of Cu were significantly higher in winter than in summer at all sites (t-test, p t-test, p < 0.05) between the concentration of total phenolic compounds and both Pb and Mn with the distance from the refinery of Baniyas. Consequently, the result of this study enhanced the usefulness of using of TPC in olive leaves as biomarker of air pollution. 展开更多
关键词 BIOMONITORING Total Phenolic Compounds Biomarker Heavy Metals OLIVE LEAVES Baniyas Oil Refinery
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Fuzzy Framework of Health Risk Assessment of Nitrates in Groundwater
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作者 Samia Chiban Adel Awad +1 位作者 Ahmad Wazzan Hanan Sheikh-Youssef 《Applied Mathematics》 2018年第6期586-601,共16页
This study provides a characterization of potential health risk associated with groundwater Nitrates in Akkar plain in Taturs governorate in Syria. Six villages were chosen for Nitrates analysis in artesian wells. The... This study provides a characterization of potential health risk associated with groundwater Nitrates in Akkar plain in Taturs governorate in Syria. Six villages were chosen for Nitrates analysis in artesian wells. The results show that Nitrates concentrations are above the natural level but still below the level of water potability and measures have to be taken to prevent Nitrates accumulation in groundwater. Comparing Nitrates dose in young children diet with reference dose and calculating the hazard index give the noncarcinogenic risk (Methemoglobinemia). Carcinogenic risk of drinking well waters with Nitrates is calculated in a probabilistic-fuzzy framework. The role of Bacterial contamination of water and its association with Nitrates pollution is discussed and we found that the two pollutants are not correlated in Akkar plain, because Nitrates come principally from fertilizers in this area while fecal coliforms come from landfill leachates and untreated wastewaters. Nitrates and FC play associated roles in gastro-intestinal disturbance and Methemoglobinemia. 展开更多
关键词 Drinking Water METHEMOGLOBINEMIA CARCINOGENIC Risk FUZZY Logic Probability Artesian Wells FECAL COLIFORMS Pollution Potability
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A high Li-ion diffusion kinetics in multidimensional and compact-structured electrodes via vacuum filtration casting 被引量:1
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作者 Jieqiong Li Ting Ouyang +3 位作者 Lu Liu Shu Jiang Yongchao Huang M.-Sadeeq Balogun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期368-376,I0010,共10页
Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(LIBs).However,simultaneously regulating these criteria for LIBs is ... Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(LIBs).However,simultaneously regulating these criteria for LIBs is desirable but remains a significant challenge.In this work,niobium pentoxide(Nb_(2)O_(5))anode and lithium iron phosphate(LiFePO_(4))cathode materials were chosen as the model materials and demonstrate that these three parameters can be simultaneously modulated by incorporation of micro-carbon fibers(MCF)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum filtration approach.Both as-prepared MNC-20 anode and MLC-20 cathode achieves high reversible areal capacity of≈5.4 m A h cm^(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm~2 s~(-1)in the half-cell configuration.The assembled MNC-20‖MLC-20 full cell LIB delivers maximum energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),respectively.The excellent electrochemical properties of the asprepared thick electrodes can be attributed to the highly conductive,mechanical compactness and multidimensional mutual effects of the MCF,CNT and active materials that facilitates rapid Li-ion diffusion kinetics.Furthermore,electrochemical impedance spectroscopy(EIS),symmetric cells analysis,and insitu Raman techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture. 展开更多
关键词 Thick electrodes Carbon nanotubes Li-ion diffusion co-efficient Vacuum filtration technique High areal capacity Lithium-ion batteries
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Gender-and Age-Group Specific Association of Persistent Organic Pollutants(POPs)Exposure with Diabetes Mellitus:Korean National Environmental Health Survey(KoNEHS)2015−2017
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作者 Inae Lee Min Joo Kim +10 位作者 Sohyeon Choi Young Joo Park Jeongim Park Gökçe Nur Ayaz Gowoon Lee Yoon Hee Cho Hye Li Jeon Chulwoo Lee Gi Jeong Cheon Min Kyong Moon Kyungho Choi 《Environment & Health》 2024年第5期322-331,共10页
Exposure to persistent organic pollutants(POPs)has been reported as a potential risk factor for diabetes in adults.However,effect modifications by sex and age,especially among Asian populations,have seldom been invest... Exposure to persistent organic pollutants(POPs)has been reported as a potential risk factor for diabetes in adults.However,effect modifications by sex and age,especially among Asian populations,have seldom been investigated.In the present study,we assessed associations of major POPs exposure including organochlorine pesticides(OCPs),polychlorinated biphenyls(PCBs),and polybrominated diphenyl ethers(PBDEs),with diabetes in Korean adults(n=1,295),a subset of the Korean National Environmental Health Survey(KoNEHS)Cycle 3(2015−2017).In the adult population,serum levels of dichlorodiphenyltrichloroethanes(DDTs)and PCB167 showed an increased odds ratio(OR)for diabetes.When stratified by gender,associations became stronger and more consistent in women:In women,serum levels of OCPs including p,p′-DDT,p,p′-dichlorodiphenyldichloroethylene(p,p′-DDE),andΣOCPs and mono-ortho PCBs,such as PCB118 and PCB157,were significantly associated with diabetes.In the male participants,however,no significant positive associations were detected.When stratified by a cutoff age of 50 years,most studied POPs except PBDEs,i.e.,p,p′-DDT,p,p′-DDE,PCB118,PCB157,PCB167,PCB138,and PCB153,showed significant associations with diabetes,in the older adults.In the younger group,however,no measured POPs showed a significant positive association.Effects of endogenous sex hormones or interaction of POPs on aryl hydrocarbon receptors may partly explain the observed differences by gender and age,although further experimental confirmations should follow.Our findings show that POPs exposure at the current levels is associated with diabetes among general Korean adults,and such associations could be modified by gender and age. 展开更多
关键词 persistent organic pollutants diabetes age GENDER toxicity equivalency factor
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汞污染对新光村小学生神经行为功能影响研究 被引量:2
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作者 王静 张翼翔 +7 位作者 白钢 王素华 王丽 高红萍 KIM Dae-Seon 姜晓峰 王国平 《包头医学院学报》 CAS 2007年第6期584-586,共3页
目的:了解新光村汞污染对小学生神经行为功能的影响。方法:采用冷原子吸收法分别测定新光村和对照点大气、饮水和食物中的汞含量,依据环境介质的摄取量和环境介质的汞含量计算出小学生日摄汞量;采用世界卫生组织推荐的神经行为核心测试... 目的:了解新光村汞污染对小学生神经行为功能的影响。方法:采用冷原子吸收法分别测定新光村和对照点大气、饮水和食物中的汞含量,依据环境介质的摄取量和环境介质的汞含量计算出小学生日摄汞量;采用世界卫生组织推荐的神经行为核心测试组合法(WHONCTB)测试小学生的神经行为功能。结果:新光村大气中汞含量明显高于对照区,饮用水和食物中的汞含量差异无显著性,新光村小学生的日平均摄汞量为16 088.1ng,显著高于对照点小学生的4 533.7ng;新光村小学生在数字译码、手工敏捷度、目标追踪和简单反应时间指标中的最慢反应时间均低于对照区小学生。结论:汞污染区小学生的部分神经行为功能发生了改变,呈现减低趋势。 展开更多
关键词 神经行为功能 汞污染 新光村小学生 包头市 燃煤 大气污染
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Deciphering the lithium storage chemistry in flexible carbon fiber-based self-supportive electrodes 被引量:7
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作者 Hao Yang Tuzhi Xiong +4 位作者 Zhixiao Zhu Ran Xiao Xincheng Yao Yongchao Huang M.-Sadeeq Balogun 《Carbon Energy》 SCIE CAS 2022年第5期820-832,共13页
Flexible carbon fiber cloth(CFC)is an important scaffold and/or current collector for active materials in the development of flexible self-supportive electrode materials(SSEMs),especially in lithium-ion batteries.Howe... Flexible carbon fiber cloth(CFC)is an important scaffold and/or current collector for active materials in the development of flexible self-supportive electrode materials(SSEMs),especially in lithium-ion batteries.However,during the intercalation of Li ions into the matrix of CFC(below 0.5 V vs.Li/Li+),the incompatibility in the capacity of the CFC,when used directly as an anode material or as a current collector for active materials,leads to difficulty in the estimation of its actual contribution.To address this issue,we prepared Ni_(5)P_(4)nanosheets on CFC(denoted CFC@Ni_(5)P_(4))and investigated the contribution of CFC in the CFC@Ni_(5)P_(4)by comparing to the powder Ni_(5)P_(4)nanosheets traditionally coated on a copper foil(CuF)(denoted P-Ni_(5)P_(4)).At a current density of 0.4 mA cm^(−2),the as-prepared CFC@Ni_(5)P_(4)showed an areal capacity of 7.38 mAh cm^(−2),which is significantly higher than that of the PNi_(5)P_(4)electrode.More importantly,theoretical studies revealed that the CFC has a high Li adsorption energy that contributes to the low Li-ion diffusion energy barrier of the Ni_(5)P_(4)due to the strong interaction between the CFC and Ni_(5)P_(4),leading to the superior Li-ion storage performance of the CFC@Ni_(5)P_(4)over the pristine Ni_(5)P_(4)sample.This present work unveils the underlying mechanism leading to the achievement of high performance in SSEMs. 展开更多
关键词 density functional theory flexible carbon fiber cloth lithium-ion batteries Ni5P4 self-supportive electrodes
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Recent Advances in Global Optimization for Combinatorial Discrete Problems 被引量:1
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作者 Adel R. Awad Samia O. Chiban 《Applied Mathematics》 2015年第11期1842-1856,共15页
The optimization of discrete problems is largely encountered in engineering and information domains. Solving these problems with continuous-variables approach then convert the continuous variables to discrete ones doe... The optimization of discrete problems is largely encountered in engineering and information domains. Solving these problems with continuous-variables approach then convert the continuous variables to discrete ones does not guarantee the optimal global solution. Evolutionary Algorithms (EAs) have been applied successfully in combinatorial discrete optimization. Here, the mathematical basics of real-coding Genetic Algorithm are presented in addition to three other Evolutionary Algorithms: Particle Swarm Optimization (PSO), Ant Colony Algorithms (ACOA) and Harmony Search (HS). The EAs are presented in as unifying notations as possible in order to facilitate understanding and comparison. Our combinatorial discrete problem example is the famous benchmark case of New-York Water Supply System WSS network. The mathematical construction in addition to the obtained results of Real-coding GA applied to this case study (authors), are compared with those of the three other algorithms available in literature. The real representation of GA, with its two operators: mutation and crossover, functions significantly faster than binary and other coding and illustrates its potential as a substitute to the traditional optimization methods for water systems design and planning. The real (actual) representation is very effective and provides two near-optimal feasible solutions to the New York tunnels problem. We found that the four EAs are capable to afford hydraulically-feasible solutions with reasonable cost but our real-coding GA takes more evaluations to reach the optimal or near-optimal solutions compared to other EAs namely the HS. HS approach discovers efficiently the research space because of the random generation of solutions in every iteration, and the ability of choosing neighbor values of solution elements “changing the diameter of the pipe to the next greater or smaller commercial diameter” beside keeping good current solutions. Our proposed promising point to improve the performance of GA is by introducing completely new individuals in every generation in GA using a new “immigration” operator beside “mutation” and “crossover”. 展开更多
关键词 EVOLUTIONARY ALGORITHMS META-HEURISTIC ALGORITHMS Real-Coding GENETIC ALGORITHMS Water Supply System New-York TUNNELS Optimal Design
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Boosted Storage Kinetics in Thick Hierarchical Micro-Nano Carbon Architectures for High Areal Capacity Li-Ion Batteries 被引量:1
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作者 Yang Wu Ting Ouyang +6 位作者 Tuzhi Xiong Zhao Jiang Yuwen Hu Jianqiu Deng Zhongmin Wang Yongchao Huang M.-Sadeeq(Jie Tang)Balogun 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2022年第4期1251-1259,共9页
A practical and effective approach to increase the energy storage capacity of lithium ion batteries(LIBs)is to boost their areal capacity.Developing thick electrodes is one of the most crucial ways to achieve high are... A practical and effective approach to increase the energy storage capacity of lithium ion batteries(LIBs)is to boost their areal capacity.Developing thick electrodes is one of the most crucial ways to achieve high areal capacity but limited by sluggish ion/electron transport,poor mechanical stability,and high-cost manufacturing strategies.Here we address these constraints by engineering a unique hierarchical-networked 10 mm thick all-carbon electrode,providing a scalable strategy to produce high areal capacity LIB electrodes.The hierarchical-networked structure utilizes micrometer-sized carbon fibers(MCFs)as building blocks,nano-sized carbon nanotubes(CNTs)as good continuous network with excellent electrical conductivity,and pyrolytic carbon as the binder and active material with excellent storage capacity.The combination of the above features endows our HNT-MCF/CNT/PC electrode with excellent performance including high reversible capacity of 15.44 mAh cm^(-2) at 2.0 mA cm^(-2) and exhibits excellent rate capability of 2.50 mAh cm^(-2) under 10.0 mA cm^(-2) current density.The Li-ion storage mechanism in HNT-MCF/CNT/PC involves dual-storage mechanism including intercalation and surface adsorption(pseudocapacitance)confirmed by the cyclic voltammetry and symmetric cell analysis.This work provides insights into the construction of high mechanical stability thick electrode for the next generation high areal capacity LIBs and beyond. 展开更多
关键词 dual storage mechanism high-areal-capacity micro-nano carbon architecture rapid kinetics and high mechanical stability thick electrode
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Enhanced Fenton-like process over Cu/L(+)-ascorbic acid co-doping mesoporous silica for toxicity reduction of emerging contaminants 被引量:1
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作者 Yuhang Liu Wenxuan Deng +2 位作者 Xiaojun Wu Chun Hu Lai Lyu 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第4期49-60,共12页
Effective removal of emerging contaminants(ECs)to minimize their impacts on human health and the natural environment is a global priority.For the removal of ECs in water,we fabricated a seaweed spherical microsphere c... Effective removal of emerging contaminants(ECs)to minimize their impacts on human health and the natural environment is a global priority.For the removal of ECs in water,we fabricated a seaweed spherical microsphere catalyst with Cu cation-πstructures by in situ doping of Cu species and ascorbic acid in mesoporous silica(Cu-C-MSNs)via a hydrothermal method.The results indicate that bisphenol A(BPA)is substantially degraded within 5 min under natural conditions,with its biological toxicity considerably weakened.Moreover,industrial wastewater could also be effectively purified by Cu-C-MSNs/H_(2)O_(2) system.The presence of metal sites and the complexation of ECs via cation-πinteraction andπ-πstacking on the catalyst surface were directly responsible for the polarization distribution of electrons,thus activating H_(2)O_(2) and dissolved oxygen(DO).The removal of contaminants could be attributed primarily to 1)the activation of H_(2)O_(2) into ^(·)OH to attack the contaminants and 2)self-cleavage because of the transfer of electrons from the contaminants to the catalysts.This study provides an innovative solution for the effective treatment of ECs and has positive implications for easing global environmental crises. 展开更多
关键词 Cation-πstructures Polarization electric field Fenton-like process Contaminants cleavage
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韩国豹猫与其它豹猫及西表猫之间的遗传分化:基于IRBP、12S rRNA和Cyt b序列的分析(英文)
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作者 KOH Hung Sun KWEON Gu Hee +3 位作者 HAM Eui Jeong JANG Kyung Hee YANG Beong Guk AN Na Hyeon 《兽类学报》 CAS CSCD 北大核心 2014年第4期374-380,共7页
利用韩国豹猫的IRBP、12S rRNA和细胞色素b(Cyt b)序列,并将其与Gen Bank中的豹猫及西表猫的上述基因进行比较,以此来重新分析韩国豹猫和其它豹猫及西表猫之间的遗传分化情况。首先,我们从18只韩国豹猫的IRBP、12S rRNA和Cyt b序列分析... 利用韩国豹猫的IRBP、12S rRNA和细胞色素b(Cyt b)序列,并将其与Gen Bank中的豹猫及西表猫的上述基因进行比较,以此来重新分析韩国豹猫和其它豹猫及西表猫之间的遗传分化情况。首先,我们从18只韩国豹猫的IRBP、12S rRNA和Cyt b序列分析中分别检测到6个等位基因、1个单倍型和3个单倍型,推测曾经发生在豹猫种群的瓶颈事件可能是本文发现的不同分子标记之间存在基因型丢失差异的原因。基于Cyt b序列分析,证实东亚的豹猫形成一个单独的进化枝,本文得到的Cyt b序列和之前发布结果支持一个分类理论,即认为东亚的豹猫就是东北森林猫。我们发现在IRBP、12S rRNA基因上,韩国豹猫和西表猫存在相同的序列,支持将西表猫和豹猫视为同一物种。 展开更多
关键词 种群瓶颈 核基因和线粒体DNA 豹猫 DNA系统分类学 西表猫 韩国
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Artificial Groundwater Recharge into Volcanic Aquifer in Jeju Island,South Korea
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作者 Yongcheol Kim Yongje Kim +1 位作者 Duckcheol Moon Kiwon Koh 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期5-6,共2页
Artificial groundwater recharge is a promising technology to address the threat to water supply posed by climate change.An artificial groundwater recharge project,which directs water from seasonal flash flooding into ... Artificial groundwater recharge is a promising technology to address the threat to water supply posed by climate change.An artificial groundwater recharge project,which directs water from seasonal flash flooding into a volcanic aquifer,is being conducted 展开更多
关键词 artificial RECHARGE vadose INJECTION Jeju ISLAND CLINKER GROUNDWATER
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