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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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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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Characteristics and origin of abnormally high porosity zones in buried Paleogene clastic reservoirs in the Shengtuo area, Dongying Sag, East China 被引量:19
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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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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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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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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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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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The Building Extraction Based on Object Oriented Classification Method in High Vegetation Coverage Area 被引量:1
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作者 Baoying Ye Nisha Bao 《Journal of Computer and Communications》 2019年第7期9-16,共8页
Quickly extraction of building information technology is an important application in urban development planning, electronic information, national defense and others. This paper takes Landsat-8 multispectral and panchr... Quickly extraction of building information technology is an important application in urban development planning, electronic information, national defense and others. This paper takes Landsat-8 multispectral and panchromatic data as data source, using the local variance method to select the optimal segmentation scale, normalized difference vegetation index (NDVI) and the normalized building index (NDBI) and panchromatic brightness value of an object oriented classification rule extraction. The high vegetation coverage area of buildings, and through the spatial relationships and distinguishing feature of collections of buildings independent buildings and villages. The results showed that Google earth high resolution image analysis and accuracy evaluation. the results of the extraction based on the overall accuracy of village extraction was 83%, the accuracy of extraction of independent buildings was 70%, according to the L8 remote sensing data, object oriented classification method can quickly and accurately extract the high vegetation coverage area of the building. 展开更多
关键词 ORIENTED CLASSIFICATION high VEGETATION COVERAGE area BUILDING
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Chemical Forms of Selenium in Corn and Rice Grown in a High Selenium Area of China 被引量:7
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作者 M.A.BEILSTEIN P.D.WHANGER G.Q.YANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1991年第4期392-398,共7页
The chemical forms of selenium were determined in maize grown near Yutangba Village and in rice grown near Haubei village, Exi Prefecture, Enshi county of Hubei Province, China. The maize sample contained 18 ppm and t... The chemical forms of selenium were determined in maize grown near Yutangba Village and in rice grown near Haubei village, Exi Prefecture, Enshi county of Hubei Province, China. The maize sample contained 18 ppm and the rice samples an average of 3.6 ppm selenium. After they were ground to obtain a fine flour, this was acid hydrolyzed with hydrochloric acid in an inert atmosphere and the hydrolyzates chromatographed on columns of Dionex DC6A resin. The results indicate that the majority of the selenium is present as selenomethionine in both rice and corn. 展开更多
关键词 Chemical Forms of Selenium in Corn and Rice Grown in a high Selenium area of China
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Cost-benefit analysis of esophageal cancer endoscopic screening in high-risk areas of China 被引量:32
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作者 Juan Yang wen-Qiang wei +3 位作者 Jin Niu Zhi-Cai Liu Chun-Xia Yang You-Lin Qiao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第20期2493-2501,共9页
AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and th... AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and the benefit-cost ratios(BCRs)of 12 EC endoscopic screening strategies.Strategies varied according to the targeted screening age,screening frequencies,and follow-up intervals.Model parameters were collected from population-based studies in China,published literatures,and surveillance data. RESULTS:Compared with non-screening outcomes,all strategies with hypothetical 100 000 subjects saved life years.Among five dominant strategies determined by the incremental cost-effectiveness analysis,screening once at age 50 years incurred the lowest NPV(international dollar-I$55 million)and BCR(2.52).Screening six times between 40-70 years at a 5-year interval[i.e., six times(40)f-strategy]yielded the highest NPV(I$99 million)and BCR(3.06).Compared with six times(40)fstrategy,screening thrice between 40-70 years at a 10-year interval resulted in relatively lower NPV,but the same BCR. CONCLUSION:EC endoscopic screening is cost-beneficial in high-risk areas of China.Policy-makers should consider the cost-benefit,population acceptance,and local economic status when choosing suitable screening strategies. 展开更多
关键词 成本效益分析 食管癌 中国 内镜 风险 检查 时间间隔 净现值
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High- and Ultrahigh-pressure Metamorphism and Retrogressive Textures of Gneiss in the Donghai Area——Evidence from gneisses in drillhole ZK2304 被引量:12
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作者 LIU Fulai, XU Zhiqin, XU Huifen and YANG Jingsui Institute of Geology, CAGS, 26 Baiwanzhuang Rd., Beijing 100037 Zhu Xiling 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第3期300-315,370,共17页
In the gneisses from the drillhole ZK2304 of the Donghai area, there have been preserved high- and ultrahigh-pressure metamorphic mineral assemblages, a series of complicated retrogressive textures and relevant metamo... In the gneisses from the drillhole ZK2304 of the Donghai area, there have been preserved high- and ultrahigh-pressure metamorphic mineral assemblages, a series of complicated retrogressive textures and relevant metamorphic reactions. In addition to garnet, jadeititic-clinopyroxene and rutile, other peak stage (M2) minerals in some gneisses include phengite, aragonite and coesite or quartz pseudomorphs after coesite. The typical peak-stage mineral assemblages in gneisses are characterized by garnet + jadeitic-clinopyroxene + rutile + coesite, garnet + jadeitic-clinopyroxene + phengite + rutile ± coesite and garnet + jadeitic-clinopyroxene + aragonite + rutile ± coesite. The grossular content (Gro) in garnet is high and may reach 50. 1 mol%. The SiO2 content of phengite ranges from 54.37% to 54.84% with 3.54-3.57 p.f.u. Quartz pseudomorphs after coesite occur as inclusions in garnet.The gneisses of the Donghai area have been subjected to multistage recrystallization and exhibit a closewise P-T evolutional path characterized by the near-isothermal decompression. The inclusion assemblage (Hb+Ep+Bi+Pl+Qz) within garnet and other minerals has recorded a pre-peak stage (Mi) epidote amphibole fades metamorphic event. High- and ultrahigh-pressure peak metamorphism (M2) took place at T=750-860℃ and P>2.7 GPa. The symplectitic assemblages after garnet, jadeitic-clinopyroxene and rutile imply a near-isothermal decompression metamorphism (M3, M4) during the rapid exhumation. Several lines of evidence of petrography and metamorphic reactions indicate that both gneisses and eclogites have experienced ultrahigh-pressure metamorphism in the Donghai area. This research may be of great significance for an in-depth study of the metamorphism and tectonic evolution in the Su-Lu ultrahigh-pressure metamorphic belt. 展开更多
关键词 GNEISS high- and ultrahigh-pressure metamorphism retrogressive texture drillhole Donghai area
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A STUDY ON THE ECOLOGICAL CLIMATES OF SOME FAMOUS TEA GROWING AREAS IN HIGH MOUNTAINOUS REGIONS OF CHINA
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作者 黄寿波 《Chinese Geographical Science》 SCIE CSCD 1991年第2期27-34,共8页
The tea tree [Camellia sinensis (L) Kuntze] is one of the world’s economic crops. It is an especially important crop for southern China. Environmental factors related to the tea yield and quality in some high mountai... The tea tree [Camellia sinensis (L) Kuntze] is one of the world’s economic crops. It is an especially important crop for southern China. Environmental factors related to the tea yield and quality in some high mountain areas of China are identified in this paper. These factors are: geology, topography, climate, hydrology, soil and vegetation. Climatological factors are the most important. Using data collected from meteorological stations which are situated at the summit and the base of high mountains, this paper discusses ecological climatic problems in growing tea in China. The ecological climatic characteristics of the famous tea areas mainly included are as follows: more . amounts of clouds and fog, less percentage of sunshine, abundant rainfall and high relative humidity in the air, temperatures that rise and fall slowly, daily and annual temperature ranges that are smaller, more days that are suitable for tea growing and low wind speeds in the lee-sides and valleys of mountains. All of these 展开更多
关键词 the FAMOUS tea GROWING areas high MOUNTAINS ECOLOGICAL climate
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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 210 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 μm) contribution>30%, Zr/Rb ratio>1.5, 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 高分辨率记录 洪水沉积 长江口 地球化学元素 泥地 晶粒尺寸 物理参数 洪水事件
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Several Typical Geomechanical Models of Deformation Fracture of Mountain in High Earthquake Intensity Area
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作者 Xiangning Xu,Lansheng Wang 1.Chengdu University of Technology,Chengdu,610059,China. 2.Chengdu Center of Hydrogeology and Engineering Geology of Sichuan Provincial GMR Bureau,Chengdu,610081,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期72-72,共1页
The deformation fracture and stability of mountain under the earthquake action is an important issue that arouses concern of researchers in the field of engineering geology.The authors,from 2000 to 2006, selected the ... The deformation fracture and stability of mountain under the earthquake action is an important issue that arouses concern of researchers in the field of engineering geology.The authors,from 2000 to 2006, selected the 1933 earthquake in Diexi zone as a typical study site to carry out the genetic mechanism research of mountain deformation-fracture caused by earthquake; in order to have comparability,the breadth 展开更多
关键词 high earthquake intensity area DEFORMATION FRACTURE mechanism Geo-mechanical MODEL bedded LANDSLIDE MODEL COLLAPSING MODEL LANDSLIDE MODEL
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Study on Selection of Dust Collectors for Large Capacity Thermal Power Units in High Altitude Areas
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作者 Wen Yiqian Cao Hongzhen Qi Jinsheng 《Meteorological and Environmental Research》 CAS 2017年第3期62-66,共5页
A dust collector is an important equipment in a thermal power plant,and reasonable selection of a dust collector is important for environmental protection in the power plant. Huaneng Xining Power Plant is located at a... A dust collector is an important equipment in a thermal power plant,and reasonable selection of a dust collector is important for environmental protection in the power plant. Huaneng Xining Power Plant is located at an elevation of 2 360 m. Based on the characteristics of the high altitude area and their special requirements for dust collectors,the selection of dust collectors for the thermal power unit in the high altitude area was studied,and then two types of dust collectors( a rotary electrode electrostatic precipitator and electric-bag composite precipitator) for the thermal power unit were compared from the aspects of technological and economical feasibility. Finally,a proposal to select a suitable dust collector for the thermal power plant was put forward. 展开更多
关键词 high ALTITUDE areas ROTARY electrode ELECTROSTATIC PRECIPITATOR Electric-bag composite PRECIPITATOR SELECTION of DUST collectors
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Application of WRF 3DVar to a high-resolution model over Beijing area
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作者 ShuiYong Fan YRGuo +6 位作者 Ming Chen JiQin Zhong YanLi Chu WWang XYHuang YingChun Wang YHKuo 《Research in Cold and Arid Regions》 2009年第2期135-142,共8页
To improve the weather forecasting over the Beijing area for the 2008 Olympic Games,a triple-nested(27/9/3km) WRFVar/WRF system with 3-h update cycle was established.Experiments have been done for a convective event t... To improve the weather forecasting over the Beijing area for the 2008 Olympic Games,a triple-nested(27/9/3km) WRFVar/WRF system with 3-h update cycle was established.Experiments have been done for a convective event that occurred on August 1,2006.The results showed that the high-resolution rapid update cycle gave a good precipitation forecast;the tunings of background error statistics(BES) and observation-error statistics in WRFVar improved the skill of the precipitation forecast;the BES for the fine domain(3 km) obtained by interpolation from its parent domain(9 km) can be used in 3 km WRFVar as a reasonable approximation.The user can now save a great deal of work related to the derivation of the fine mesh BES from the forecast over a period of time;the rapid update cycle with 3-h frequency has satisfied the forecast,and the update cycle with 1-h frequency was not necessary. 展开更多
关键词 Beijing area WRFVar WRF model high resolution rapid update cycle
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