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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing
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作者 Lina Cai Jie Yin +3 位作者 Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期66-86,共21页
Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was propose... Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture areas.This methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental factors.The fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 m.In the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in detail.The results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture area.As for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open waters.The water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the future.the fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world. 展开更多
关键词 mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis
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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM
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作者 WANG Yanxia YANG Lisha +1 位作者 HUANG Xiaoyuan ZHOU Ruliang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2025-2042,共18页
Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are n... Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources. 展开更多
关键词 high temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection
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Effects of Health Education with Problem-Based Learning Approaches on the Knowledge, Attitude, Practice and Coping Skills of Women with High-Risk Pregnancies in Plateau Areas
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作者 Ying Wu Suolang Sezhen +5 位作者 Renqing Yuzhen Hong Wei Zhijuan Zhan Baima Hongying Yuhong Zhang Lihong Liu 《Open Journal of Nursing》 2024年第5期192-199,共8页
Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approach... Objective: Given the unique cultural background, way of life, and physical environment of the Tibetan Plateau, this study aims to investigate the effects of health education using problem-based learning (PBL) approaches on the knowledge, attitude, practice, and coping skills of women with high-risk pregnancies in this region. Methods: 76 high-risk pregnancy cases were enrolled at Tibet’s Linzhi People’s Hospital between September 2023 and April 2024. 30 patients admitted between September 2023 and December 2023 were selected as the control group and were performed with regular patient education. 46 patients admitted between January 2024 and April 2024 were selected as the observation group and were performed regular patient education with problem-based learning approaches. Two groups’ performance on their health knowledge, attitude, practice and coping skills before and after interventions were evaluated, and patient satisfaction were measured at the end of the study. Results: There was no statistical significance (P P P Conclusions: Health education with problem-based learning approaches is worth promoting as it can help high-risk pregnant women in plateau areas develop better health knowledge, attitude and practice and healthier coping skills. Also, it can improve patient sanctification. 展开更多
关键词 Plateau areas Patients with high-Risk Pregnancies Problem-Based Learning Health Education Health Knowledge Attitude and Practice Coping Skills
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High surface area biocarbon monoliths for methane storage 被引量:1
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作者 Elizabeth Michaelis Renfeng Nie +1 位作者 Douglas Austin Yanfeng Yue 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第5期1308-1324,共17页
New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable... New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable energy source for heating and electricity generation due to its high combustion value.Currently,natural gas accounts for a large portion of electricity generation and chemical feedstock in manufacturing plastics and other commercially important organic chemicals.In the near future,natural gas will be widely used as a fuel for vehicles.Therefore,a practical storage device for its storage and transportation is very beneficial to the deployment of natural gas as an energy source for new technologies.In this tutorial review,biomaterials-based carbon monoliths(CMs),one kind of carbonaceous material,was reviewed as an adsorbent for natural gas(methane)adsorption and storage. 展开更多
关键词 Activated carbon Carbon monolith Methane storage high surface area Activation agent
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Performance evaluation of CLM5.0 in simulating liquid soil water in high mountainous area,Northwest China
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作者 ZHANG Lan-hui NING Feng-wei +2 位作者 BAI Xu-liang ZENG Xuan HE Chan-sheng 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1865-1883,共19页
The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) i... The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) in simulating liquid SWC was evaluated against observations from nine in-situ sites in the upper reach of the Heihe River Watershed(HRW),Northwest China.The CLM5.0 shows reliable performance in the study area with correlation coefficients(R) ranging between 0.79–0.93,root mean standard errors(RMSE)ranging between 0.044–0.097 m^(3)/m^(3),and the mean bias(BIAS) ranging between-0.084–0.061 m^(3)/m^(3).The slightly worse performance of CLM5.0 than CLM4.5 on alpine meadow and grassland is mainly caused by the revised canopy interception parameterization.The CLM5.0 overestimates interception and underestimates evapotranspiration(ET) on both alpine meadow and grassland during the growth period.The systematical overestimations at all the grassland sites indicate that the underestimation of ET is much larger than the overestimation of interception on grassland during growth period,while the errors of simulated interception and ET are partially canceled out on alpine meadow.Moreover,the underestimation of ET is more responsible for the overestimation of SWC than the overestimation of interception in the high mountainous area.It is necessary to estimate reasonable empirical parameter α(proportion of leaf water collection area) in interception parameterization scheme and further improve the dry surface layerbased soil evaporation resistance parameterization introduced in CLM5.0 in future researches.The performance of CLM5.0 is better under completely frozen stage than thawing stage and freezing stage,because of low variations of liquid SWC caused by extremely low hydraulic conductivity of soils.The underestimation of liquid SWC under frozen state is caused by underestimation of soil temperature,which leads to more ice mass and less liquid water in total water content. 展开更多
关键词 Performance evaluation Soil water content CLM5.0 EVAPOTRANSPIRATION high mountainous area
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Settlement Control Technology of High Filled Soil-Rock Embankment in Alpine and High-Altitude Areas
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作者 Guangxi Wu 《Journal of World Architecture》 2023年第4期75-81,共7页
China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of diff... China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of different sizes in mountainous areas are unavoidable,and the settlement of high-fill embankments is usually the most concerned issue in high-fill projects.According to the current research of highway projects,most of the high embankments in mountainous areas are soil-rock mixed embankments or rock-filled embankments,and their post-construction settlements are directly related to construction technology and the type of filler used.In this paper,the problems in the settlement control of earth-filled embankment and related factors are analyzed in detail.The settlement control technology of high-fill embankment in high-cold and high-altitude areas is also discussed,so as to ensure the overall quality of high-fill embankment. 展开更多
关键词 high-altitude and cold areas high soil-rock embankment Settlement control technology
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Cultivation Techniques for High-yield Corn in a Karst Area of Southwest Guizhou
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作者 郭银萍 王永树 黄蔚 《Agricultural Science & Technology》 CAS 2014年第8期1339-1341,共3页
The cultivation techniques for high-yield corn in a karst area of southwest Guizhou were elaborated in this research from the respects of choosing farmland, preparing farmland, picking good seeds, timely sowing, ratio... The cultivation techniques for high-yield corn in a karst area of southwest Guizhou were elaborated in this research from the respects of choosing farmland, preparing farmland, picking good seeds, timely sowing, rational close planting, im-proving the quality of planting, mulching, scientific fertilization, field management, timely harvest, etc. we hoped to provide a reference for the realization of high-effi-ciency corn planting in mountain areas. 展开更多
关键词 Karst area CORN high yield Cultivation technique
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Influence of Global Warming on High-active Agricultural Development in Chaoyang Area 被引量:1
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作者 周广学 李普庆 周晓东 《Meteorological and Environmental Research》 CAS 2010年第3期42-44,共3页
The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in... The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in protective field,gross agricultural output value.The results showed that climate warming had a very significant positive effect on the development of high-active agriculture in Chaoyang. 展开更多
关键词 Chaoyang area INFLUENCE high-active agriculture China
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Characteristics and origin of abnormally high porosity zones in buried Paleogene clastic reservoirs in the Shengtuo area, Dongying Sag, East China 被引量:23
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作者 Cao Yingchang Yuan Guanghui +5 位作者 Li Xiaoyan Wang Yanzhong Xi Kelai Wang Xiaoming Jia Zhenzhen Yang Tian 《Petroleum Science》 SCIE CAS CSCD 2014年第3期346-362,共17页
There are three abnormally high porosity zones developed in buried Paleogene nearshore subaqueous fan and sublacustrine fan clastic'reservoirs at 2,800-3,200 m, 3,250-3,700 m and 3,900- 4,400 m, respectively, within ... There are three abnormally high porosity zones developed in buried Paleogene nearshore subaqueous fan and sublacustrine fan clastic'reservoirs at 2,800-3,200 m, 3,250-3,700 m and 3,900- 4,400 m, respectively, within the Shengtuo area of the Dongying Sag. Here the porosity of reservoirs buried deeper than 4,000 m can still be greater than 20%. Investigation of these three abnormally high porosity (AHP) zones in the 3rd to 4th member of the Paleogene Shahejie Formation in the Shengtuo area was carried out with utilization of core observation, thin section identification, SEM observation, image analysis, core physical property testing and other technical methods. The results show that, the AHP zones in 2,800-3,200 m and 3,250-3,700 m are visible pores primary AHP zones dominated by significant primary intergranular pores (more than 50% of the total porosity), while secondary pores and micropores in authigenic clays may develop in some reservoirs. AHP reservoirs in the AHP zone of 3,900-4,400 m are dominated by micropores in matrix, visible pores are mainly grain dissolution pores but with low absolute content (〈 1%), so this zone belongs to the micropores primary AHP zone. The genesis of the three AHP zones was studied to distinguish between porosity enhancement and porosity preservation. Our research shows that, in deeply buried clastic reservoirs in the Shengtuo area, mineral dissolution occurred in a relatively closed diagenetic system with high temperature and high salinity. Reservoir rocks underwent extensive feldspar dissolution, while detrital carbonate grains and carbonate cements show no evidence of extensive dissolution. Although significant feldspar dissolution pores developed, feldspar dissolution enhanced porosity only a little due to the precipitation of almost isovolumetric dissolution products in the nearby primary intergranular pores in forms of authigenic clays and quartz cements. Net enhanced porosity originating from feldspar dissolution is generally less than 0.25%. Thus, the subsurface dissolution has little impact on the mid-deep buried high porosity reservoirs. Reservoirs in braided channels of middle fans in sublacustrine fans and reservoirs in the middle-front of fan bodies of nearshore subaqueous fans provide the basis for the development of AHP zones. The shallow development of fluid overpressure and early hydrocarbon emplacement have effectively retarded compaction and carbonate cementation, so that the high porosity in the superficial layers is preserved in the mid-deep layers. These are the main controlling factors in the development of AHP zones. 展开更多
关键词 Dongying Sag Shengmo area abnormally high porosity zone pores GENESIS
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Assessment of Human Impacts on Vegetation in Built-up Areas in China Based on AVHRR,MODIS and DMSP_OLS Nighttime Light Data,1992–2010 被引量:5
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作者 LIU Qinping YANG Yongchun +2 位作者 TIAN Hongzhen ZHANG Bo GU Lei 《Chinese Geographical Science》 SCIE CSCD 2014年第2期231-244,共14页
Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment espec... Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas.In this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to 2010.Firstly,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light data.This improved algorithm has the advantages of high accuracy and speed.Secondly,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI.HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects.The results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up areas.We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas.The negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban scales.China′s national policies,social and economic development affected vegetation changes in the built-up areas.The findings can provide a scientific basis for municipal planning departments,a decision-making reference for government,and scientific guidance for sustainable development in China. 展开更多
关键词 vegetation change human impact urbanization built-up areas nighttime light data Normalized Difference Vegetation Index(NDVI)
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Contamination of Fungi and Mycotoxins in Foodstuffs in High Risk Area of Esophageal Cancer 被引量:38
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作者 ZHANG XIANG-HONG XIE TONG-XIN +5 位作者 LI SHAO-SEN WANG JUN-LING YAN XIA WANG ZHAO-YI WANG FENG-RONG AND FU CHENG-GUANG(Department of Experimental Pathology, Hebei Medical University,Shijiazhuang 050017, China Research Center of Physical and Chemical Analysis, He 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第2期140-146,共7页
Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiologi... Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiological level, fungal and mycotoxin contaminations of local foodstuffs in Cixian County were analyzed using classical fungal culture methods and HPLC. From 1990 to 1994, 220 corn/wheat samples and 34 corn samples were studied. As a control, 26 corn samples collected from a relatively low incidence area of Eca in Zanhuang County were analyzed for mycotoxins in 1990. The results showed that fungal contamination in corn and wheat was severe and that several of the predominant contaminating fungi such as Furasium moniliforme, etc. were carcinogenic. HPLC results showed that the detection rate and mean content of the mycotoxin sterigmatocystin (ST) in the mountainous area (5/8; 9. 14 μg/kg) were significantly higher than those in the hilly (0; 0) and plain areas (1/18; 1. 29 μg/kg) as well as in low risk area control samples (3/26; 0. 76 μg/kg). Detection rates of deoxynivalenol (DON) in mountainous and hilly areas (5/8, 4/8 respectively) were slightly higher than that in plain area (8/18), while the mean content of DON in the plain area was significantly higher (90. 45-170. 22 vs 50. 56 and 46. 45 μg/kg).Among the different aflatoxins, AFB1 was detected in samples from the two villages in the plain area for the subsequent two years. The mean content of AFB1 was 0. 0183μg/kg, and the highest level was 0. 0497 μg/kg. No AFB1 was detected in the samples from mountainous and hilly areas. AFG1 was detected in more than half of all the samples, and its concentration ranged from 8. 77 to 46. 51 ng/kg. No AFG2 was found in the samples. Thus, the results suggest that at present, fungal and mycotoxin contamination of foodstuffs in Cixian County are quite common. 展开更多
关键词 LI WANG Contamination of Fungi and Mycotoxins in Foodstuffs in high Risk area of Esophageal Cancer
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Preparation and Characterization of Porous Yttrium Oxide Powders with High Specific Surface Area 被引量:3
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作者 李永绣 林小云 +2 位作者 王义振 罗军明 孙伟丽 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第1期34-38,共5页
The porous cubic yttrium oxides with high specific surface area were prepared yttrium nitrate and its complex formed with methyl salicylate. The specific surface area by the explosive decomposition of and properties o... The porous cubic yttrium oxides with high specific surface area were prepared yttrium nitrate and its complex formed with methyl salicylate. The specific surface area by the explosive decomposition of and properties of powders synthesized at various temperatures were characterized using BET, X-ray diffraction (XRD), infrared spectra (IR), and scanning electron microscopy (SEM). The results indicate that the highest specific surface area is found to be 65.37 m^2·g^-1 at the calcination temperature of 600 ℃, and then decreases to 20.33 m2· g^- 1 with the calcination temperature rising from 600 to 900 ℃. The powders show strong surface activity for adsorping water and carbon dioxide in air, which also decreases with the rising calcination temperature. The drop both on the surface area and surface activity of samples at higher temperatures may be due to pore-narrowing(sintering) effects. 展开更多
关键词 porous yttrium oxide high surface area explosive decomposition rare earths
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High resolution records of flood deposition in the mud area off the Changjiang River mouth during the past century 被引量:3
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作者 胡刚 李安春 +3 位作者 刘健 徐刚 梅西 孔祥淮 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期909-920,共12页
This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-re... This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 21~pb dating and was sampled at 1-2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size (14.32-96.39 gm) contribution〉30%, Zr/Rb ratio〉l.5, and magnetic susceptibility〉16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods. 展开更多
关键词 high resolution grain size flood deposition mud area the Changjiang River
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Distribution Characteristics of High Temperature Damage and Its Influence on the Rice Yield in the Area along Huaihe River 被引量:3
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作者 FENG De-hua1,JIANG Yue-lin1,YANG Tai-ming2,CHEN Jin-hua2 1.College of Resources & Environment,Anhui Agricultural University,Hefei 230036,China 2.Anhui Meteorological Science Research Institute,Hefei 230031,China 《Meteorological and Environmental Research》 CAS 2011年第3期73-76,80,共5页
[Objective] The research aimed to study the distribution characteristics of high temperature damage and its influence on the rice yield in the area along Huaihe River.[Method] The meteorological data of 10 stations in... [Objective] The research aimed to study the distribution characteristics of high temperature damage and its influence on the rice yield in the area along Huaihe River.[Method] The meteorological data of 10 stations in the area along Huaihe River during 1965-2009 and the yield data of Anhui single-season middle rice during 1967-2006 were selected.The occurrence characteristic of summer high temperature weather and the intensity of high temperature damage in the area along Huaihe River were analyzed.Based on the previous high temperature damage index of rice,Changfeng County where was the typical rice planting zone in the area along Huaihe River was as the representation,and the yield damage loss rate risk of high temperature damage in Changfeng was analyzed by combining with the historical yield data.[Result] The high temperature weather in the area along Huaihe River frequently happened.The high temperature damage presented 'N' shape trend from west to east.The occurrence frequency of high temperature weather in Huainan and Bengbu where were in the middle area along Huaihe River was more and was less in Huoqiu and Shouxian where were near the south mountain area of Anhui.The occurrence time mainly focused from the middle and last dekads of July to the first dekad of August after the plum rain.At this time,it was the booting,heading and flowering periods of single-season middle rice,and the influence on the rice yield was obvious.The damage loss rate of single-season middle rice yield in Changfeng County along Huaihe River continued to increase as the increasing of high temperature damage duration.But the occurrence probability decreased.The intensity grade of high temperature damage disaster loss rate which happened frequently concentrated mainly in levels I and II.The longer the high temperature damage duration in the reproductive growth stage of rice was,the bigger the damage loss rate was.But the corresponding occurrence probability was small,and vice versa.[Conclusion] The research provided the reference for assessing the high temperature disaster risk. 展开更多
关键词 high temperature damage Distribution characteristic RICE Disaster loss rate area along Huaihe River China
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Nitrogen and sulfur dual-doped high-surface-area hollow carbon nanospheres for efficient CO2 reduction 被引量:4
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作者 Guodong Li Yongjie Qin +6 位作者 Yu Wu Lei Pei Qi Hu Hengpan Yang Qianling Zhang Jianhong Liu Chuanxin He 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第5期830-838,共9页
The electrochemical reduction of CO2(CO2 RR) can substantially contribute to the production of useful chemicals and reduction of global CO2 emissions. Herein, we presented N and S dual-doped high-surface-area carbon m... The electrochemical reduction of CO2(CO2 RR) can substantially contribute to the production of useful chemicals and reduction of global CO2 emissions. Herein, we presented N and S dual-doped high-surface-area carbon materials(SZ-HCN) as CO2 RR catalysts. N and S were doped by one-step pyrolysis of a N-containing polymer and S powder. ZnCl2 was applied as a volatile porogen to prepare porous SZ-HCN. SZ-HCN with a high specific surface area(1510 m2 g–1) exhibited efficient electrocatalytic activity and selectivity for CO2 RR. Electrochemical measurements demonstrated that SZ-HCN showed excellent catalytic performance for CO2-to-CO reduction with a high CO Faradaic efficiency(~93%) at-0.6 V. Furthermore, SZ-HCN offered a stable current density and high CO selectivity over at least 20 h continuous operation, revealing remarkable electrocatalytic durability. The experimental results and density functional theory calculations indicated that N and S dual-doped carbon materials required lower Gibbs free energy to form the COOH* intermediate than that for single-N-doped carbon for CO2-to-CO reduction, thereby enhancing CO2 RR activity. 展开更多
关键词 high specific surface area Hollow structure Carbon-based catalysts CO2 reduction reaction Electrocatalytic selectivity
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Reservoir characteristics and hydrocarbon accumulation of Carboniferous volcanic weathered crust of Zhongguai high area in the western Junggar Basin, China 被引量:3
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作者 LI Hu TANG Hong-ming +4 位作者 QIN Qi-rong FAN Cun-hui HAN Song YANG Cang ZHONG Cheng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第11期2785-2801,共17页
Based on the drilling,cores,logs,seismic,laboratory analysis and so on,reservoir characteristics and hydrocarbon accumulation of Carboniferous volcanic weathered crust in Zhongguai high area are studied.Volcanic rocks... Based on the drilling,cores,logs,seismic,laboratory analysis and so on,reservoir characteristics and hydrocarbon accumulation of Carboniferous volcanic weathered crust in Zhongguai high area are studied.Volcanic rocks were formed in an island arc environment.The lithology is mainly andesite and tuff;Reservoir spaces are mainly secondary pore,fracture and their combination forms,fractures have a better effect on reservoir seepage;There are four layer structures of volcanic weathered crust,weathered clay layer,strongly weathered zone,weakly weathered zone and unweathered zone and strongly weathered zone is the best,which is the main reservoir development zone;The development of reservoir is mainly affected by weathering-leaching,lithology and lithofacies,and fault(fracture);Effective reservoirs could reach to 480 m thickness(high quality reservoirs are within 240 m).Carboniferous volcanic reservoirs are distributed along three zones,which are near the fault zone,high structural part,favorable lithofacies development zone,and one plane,which is near the unconformity. 展开更多
关键词 reservoir characteristics volcanic weathered crust fracture hydrocarbon accumulation CARBONIFEROUS Zhongguai high area
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Novel Salt-Assisted Combustion Synthesis of High Surface Area Ceria Nanopowders by An Ethylene Glycol-Nitrate Combustion Process 被引量:1
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作者 陈伟凡 李凤生 +1 位作者 于吉义 李永绣 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第4期434-439,共6页
A novel salt-assisted combustion process with ethylene glycol as a fuel and nitrate as an oxidant to synthesize high surface area celia nanopowders was reported. The effects of various tunable conditions, such as fuel... A novel salt-assisted combustion process with ethylene glycol as a fuel and nitrate as an oxidant to synthesize high surface area celia nanopowders was reported. The effects of various tunable conditions, such as fuel-to-oxidant ratio, type of salts, and amount of added salts, on the characteristics of the as-prepared powders were investigated by X-ray diffraction, transmission electron microscopy and BET surface area measurement. A mechanism scheme was proposed to illustrate the possible formation processes of well-dispersed ceria nanoparticles in the salt-assisted combustion synthesis. It was verified that the simple introduction of leachable inert inorganic salts as an excellent agglomeration inhibitor into the redox mixture precursor leads to the formation of well-dispersed ceria particles with particle size in the range of 4 ~6 nm and a drastic increase in the surface area. The presence of KCl results in an over ten-fold increment in specific surface area from 14.10 m^2·g^-1 for the produced ceria powders via the conventional combustion synthesis process to 156.74 m^2·g^-1 for the product by the salt-assisted combustion synthesis process at the same molar ratio of ethylene glycol-nitrate. 展开更多
关键词 salt-assisted combustion synthesis CERIA NANOPOWDERS ethylene glycol high surface area rare earths
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Space-time Relationship Between Urban Municipal District Adjustment and Built-up Area Expansion in China 被引量:1
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作者 WANG Kaiyong QI Wei 《Chinese Geographical Science》 SCIE CSCD 2017年第2期165-175,共11页
Municipal district adjustment and built-up area expansion are two main forms of urban spatial expansion. Using geometric methods, this study constructed a space-time path method to characterize the space-time relation... Municipal district adjustment and built-up area expansion are two main forms of urban spatial expansion. Using geometric methods, this study constructed a space-time path method to characterize the space-time relationship between municipal district adjustment and built-up area expansion, and drew the space-time path sets of major prefecture level cities from 2000 to 2010 by constructing a coordinate system of the standardized built-up areas and municipal district areas. This divided them into four quadrants, namely, H-H, L-H, L-L, and H-L, based on the relative mean value to evaluate overall and individual stability by three indexes of the trajectory vectors, namely, direction, length, and slope. Results provide the following conclusions. 1) Municipal district adjustment is an effective spatial expansion way for city-scale promotion in China. Since 2000, municipal district adjustments have been mainly distributed in the eastern coastal regions and mid-western capital cities along with their surrounding cities. 2) Municipal district adjustment affects the scale and status of a city in China. Many cities that have expanded municipal districts behave stably and cross quadrants. 3) Great majority second-tier cities have effectively promoted their scale and status through municipal district adjustment. The municipal district adjustment of medium and small cities in the mid-west area is relatively advanced compared with city development. 4) Municipal district adjustment with minimal magnitude is severely restricted from upgrading the scale and status of a city. The transformation from entirely incorporated counties or cities to municipal districts should be the mainstream in future municipal district adjustment. 展开更多
关键词 municipal district adjustment built-up area space-time path administration division
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Preparation of Zirconia-Ceria Powders with High Specific Surface Area 被引量:1
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作者 Wang Enguo Mei Fang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第z1期46-48,共3页
Zirconia-ceria mixed oxide powders were prepared by high temperature aging method.The effects of the temperature and the time of aging, cerium content and calcination on powder performance were studied.The result show... Zirconia-ceria mixed oxide powders were prepared by high temperature aging method.The effects of the temperature and the time of aging, cerium content and calcination on powder performance were studied.The result shows that high temperature aging is an efficient way of preparation of ZrO2-CeO2 mixed oxide powders with high specific surface area and good thermal stability, and that addition of a small amount of cerium to hydrous zirconia can promote the preparation of high specific surface area powders. 展开更多
关键词 ZIRCONIA CERIA high temperature AGING high specific surface area RARE earths
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Synthesis of Macro-Mesostructured γ-Al_2O_3 with Large Pore Volume and High Surface Area by a Facile Secondary Reforming Method 被引量:2
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作者 Meng Xiuhong Duan Linhai +2 位作者 Xie Xiaohua Wang Qiang Wang Haiyan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第2期20-28,共9页
Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the ... Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the reaction temperature, the first aging temperature and the second aging temperature, were investigated. The textural properties of γ-Al2O3 were characterized by means of N2 adsorption-desorption isotherms, X-ray powder diffractometry (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and thermogravimetry (TG). The experimental results indicated that AACH and amorphous A1OOH were the precursors of alumina, which were formed via precipitation from solutions after reaction of aluminum sulphate with ammonium hydrogen carbonate. The precursor nanocrystallites grew and re-assembled during the secondary reforming process, which resulted in an increased pore size and pore volume and a decreased bulk density. The as-synthesized γ-Al2O3 materials featured meso/macroporosity, large pore volume (2.175 cm^3/g), high surface area (237.8 m^2/g), and low bulk density (0.284 g/mL). 展开更多
关键词 Γ-AL2O3 macro-mesostructured reforming method large pore volume high surface area.
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