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Determining safe yield and mapping water level zoning in groundwater resources of the Neishabour Plain 被引量:1
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作者 Parisa Kazerani Ali Naghi Ziaei Kamran Davari 《Journal of Groundwater Science and Engineering》 2023年第1期47-54,共8页
Groundwater is a crucial sources of water supply,especially in arid and semi-arid areas around the world.With uncontrolled withdrawals and limited availability of these resources,it is essential to determine the safe ... Groundwater is a crucial sources of water supply,especially in arid and semi-arid areas around the world.With uncontrolled withdrawals and limited availability of these resources,it is essential to determine the safe yield of these valuable resources.The Hill method approach was used in this study to determine the safe yield the Neishabour aquifer in Khorasan Razvi province in Iran.The results showed that the safe yield in the Neishabour aquifer is 60%lower than the current pumping amounts during the study period,indicating that further overdrafts could result in the destruction of this aquifer.This highlights the importance of using the Hill method to estimate the permitted exploitation from other aquifers,thus preventing problems caused by over-extraction and maintaining stability of global groundwater levels. 展开更多
关键词 Hill method Water level zoning maps Groundwater pumping Safe yield Groundwater crisis
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The Comparative Performance of Nutrient-Film Technique and Deep-Water Culture Method of Hydroponics for GREENBOX Technology
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作者 Mya Alexandria Catherine Griffith George Paul Buss +6 位作者 Paige Ann Carroll Xiusheng Yang John L. Griffis Jr. Galen Papkov Sarah Bauer Kathryn Jackson Ankit Kumar Singh 《Agricultural Sciences》 2023年第8期1108-1120,共13页
With the rising pressures on food security, GREENBOX technology was developed as an avenue for fresh leafy vegetable crop production in urban settings. GREENBOX units were designed to be thermally insulated and climat... With the rising pressures on food security, GREENBOX technology was developed as an avenue for fresh leafy vegetable crop production in urban settings. GREENBOX units were designed to be thermally insulated and climate controlled, with an artificial lighting source that utilized soilless cultivation techniques. Previous studies conducted on GREENBOX technology used the Nutrient Film Technique (NFT);however, various hydroponic methods exist, such as the Deep-Water Culture (DWC) method being the most used. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the crop growth performance between DWC and NFT systems using GREENBOX technology. The following study monitored environmental conditions and compared productivity and biomass data of Rex Butterhead Lettuce crops between DWC and NFT systems. We assembled two GREENBOX units using commercially available materials and the standard nutrient solution for fertigation. The crops grown in DWC and NFT were in a 4 × 6 configuration. The DWC and NFT systems were used to grow Lettuce Lactuca sativa “Rex Butterhead” over 30 days to full bloom from prepared plugs grown for 14 days. We collected environmental data including Photosynthetic Photon Flux Density (PPFD, μmol/m<sup>2</sup>∙s), Daily Light Integral (DLI, mol/ m<sup>2</sup>∙d), temperature (˚C), relative humidity (%), and Vapor Pressure Deficit (VPD, kPa). We collected lettuce crop growth data, which included wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). We derived data, including the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>), from previously collected data. We used descriptive statistics to present the collected data. A paired t-test was performed to understand the differences in biomass and productivity parameters between the DWC and NFT-grown lettuce crops. Both the DWC and NFT-grown crops could grow lettuce crops to harvest weight at full bloom. Observed data demonstrated that the biomass parameters and productivity did not differ significantly between the two hydroponics techniques. Therefore, we believe both hydroponic methods may be similar in growth performance and may be used in future iterations of GREENBOX design and prove suitable for fresh vegetable crop production in urban settings. 展开更多
关键词 Controlled Environment Agriculture Food Insecurity GREENBOX HYDROPONICS LETTUCE
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DISCUSSION OF SOME CONCEPTIONS OF A WATER MASS BASED ON THE THEORY OF FUZZY SETS
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作者 李凤岐 苏育嵩 +1 位作者 王凤钦 喻祖祥 《中国海洋大学学报(自然科学版)》 CAS CSCD 1989年第S1期430-444,共15页
The fundamental principle for differentiating water masses is a strict consideration of their relative "interior homogeneity" and obvious "exterior differences" with others in characteristics. The ... The fundamental principle for differentiating water masses is a strict consideration of their relative "interior homogeneity" and obvious "exterior differences" with others in characteristics. The conceptions of water type, water mass and water system are dealt with on the basis of the theory of fuzzy sets. A proposal to apply the theory of fuzzy sets to define the water mass and its core, independent area, boundary and mixing area is put forward.As an example, the membership function of the surface water masses in the Yellow Sea and East China Sea in August, 1979, are considered. Their cores, independent areas, boundaries, mixing areas and the approximation degrees between different water masses are calculated respectively. The water masses are ranged according to their fuzzy degrees. 展开更多
关键词 WATER mass fuzzy SETS WATER type WATER system MEMBERSHIP function the YELLOW SEA the East China SEA
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The Comparative Performance of Soil-Based Systems with Hydroponics
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作者 Paige Ann Carroll George Paul Buss +6 位作者 Mya Alexandria Catherine Griffith Xiusheng Yang John L. Griffis Jr. Galen Papkov Sarah Bauer Kathryn Jackson Ankit Kumar Singh 《Agricultural Sciences》 2023年第8期1087-1097,共11页
Conventional soil-based agriculture is resource-intensive, utilizing large amounts of land and water, thereby placing a strain on Earth’s natural resources. Soil-based agricultural techniques create environmental iss... Conventional soil-based agriculture is resource-intensive, utilizing large amounts of land and water, thereby placing a strain on Earth’s natural resources. Soil-based agricultural techniques create environmental issues such as soil degradation, deforestation, and groundwater pollution from the mass implementation of fertilizers and pesticides. Agricultural crop production using hydroponics has shown promise to be less resource intensive and provide a faster turnaround in crop production. Soilless cultivation using hydroponics promises to relieve some pressure on Earth’s ecosystems and resources by utilizing lesser land and water footprint. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the growth of Lettuce Lactuca sativa “Rex Butterhead” crop grown using soil and soilless methods to analyze the growth performance in each setting. Crops grown in the soil-based medium were raised in the FGCU Food Forest, used a mix of soil and potting mix, watered regularly, and followed standard Integrated Pest Management (IPM) practices. Crops grown hydroponically were grown in a thermally insulated grow tent with an artificial lighting source, ventilation, environmental controls, and the Deep-Water Culture (DWC) method. Lettuce plugs were grown for 15 days in controlled environments until two leaves after the cotyledons had developed and were ready for transplant. Plugs were transplanted into a 4 × 6 matrix at the FGCU Food Forest and the DWC growth system. Crops were grown to full bloom and ready for harvest in the soil (60 days) and soilless (30 days) based setups. We collected crop growth data, including wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). From the collected data, we derived the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>). Descriptive statistics were used to describe the collected and derived data. We investigated the slopes of regression lines for each growth curve which derived the differences in biomass and productivity parameters between lettuce grown using soil and hydroponics. Both growing methods can grow lettuce crops to full bloom and to adequate harvest weight. The biomass parameters and productivity differ significantly between the growing methods. The lettuce crops grown using hydroponics increase in wet weight statistically and significantly faster than those grown in soil (p < 0.0001). Therefore, we determined that a hydroponic method of crop production may provide better crop output and biomass indicators measured than soil-based growth. 展开更多
关键词 Controlled Environment Agriculture HYDROPONICS LETTUCE Soilless Agriculture Urban Agriculture
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The Comparative Performance of Plug Preparation Using Different Fertilizer Sources and Concentrations
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作者 George Paul Buss Paige Ann Carroll +6 位作者 Mya Alexandria Catherine Griffith Xiusheng Yang John L. Griffis Galen Papkov Sarah Bauer Kathryn Jackson Ankit Kumar Singh 《Agricultural Sciences》 2023年第9期1193-1205,共13页
Plugs are crucial for initiating crop production in greenhouses, soil, and controlled environment agriculture (CEA). Vegetable, fruiting, ornamental, and other horticultural crops that utilize plugs for production hav... Plugs are crucial for initiating crop production in greenhouses, soil, and controlled environment agriculture (CEA). Vegetable, fruiting, ornamental, and other horticultural crops that utilize plugs for production have demonstrated superior transplant establishment rate, plant health, and total yield. The APS Laboratory for Sustainable Food at Florida Gulf Coast University investigated the quality of plugs grown based on different concentrations and fertigation sources using synthetic and organic sources. We carried out the growth of “Rex Butterhead” Lettuce (Latuca sativa) plugs with five different fertigation treatments, 1) full-strength synthetic starter fertilizer solution;2) half-strength synthetic starter fertilizer solution;3) full-strength organic starter fertilizer solution;4) half-strength organic starter fertilizer solution, and 5) no fertilizer for control. Fertilizer treatments were formulated following manufacturer recommendations. The seeds were sown in Oasis<sup>®</sup> Horticubes and saturated every day with the different fertilizer treatments. The plugs were cultivated for 15 days in a controlled environment until two leaves after the cotyledons had developed. After 15 days, we collected data which included wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (mg/cm<sup>2</sup>). In addition, we derived data including the Leaf Area Index (LAI, cm<sup>2</sup>/cm<sup>2</sup>) and Specific Leaf Area (SLA, cm<sup>2</sup>/g). Descriptive statistics were used to describe the biomass data. A Tukey’s HSD test was carried out to understand the differences between the fertilizer sources. We determined there was a statistically significant difference (P = 7.34E−29) in the measured plug growth parameters due to the various fertigation sources. We found that all fertilizer treatments produced viable plugs except for the control treatment. Of all the treatments, we concluded the half-strength organic treatment produced the more vigorous plugs with the greatest wet weight (g) and largest total leaf area (cm<sup>2</sup>) which was statistically significantly different. Results from this study may inform growers about appropriate fertilizer options for plug production. 展开更多
关键词 Controlled Environments FERTIGATION LETTUCE Plugs Urban Agriculture
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The Assessment of Growth Performance of Brassica rapa var. chinensis ‘Li Ren Choi’, Spinacia oleracea ‘Auroch’, Eruca sativa ‘Astro’, and Brassica rapa var. japonica Using GREENBOX Technology
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作者 George Paul Buss Paige Ann Carroll +6 位作者 Mya Alexandria Catherine Griffith Xiusheng Yang John L. Griffis Jr. Galen Papkov Sarah Bauer Kathryn Jackson Ankit Kumar Singh 《Agricultural Sciences》 2023年第9期1222-1237,共16页
Obtaining nutritious food is becoming increasingly difficult due to the growing urban population and the degradation of soil, water, and air from mechanized and industrialized agricultural techniques. More than half t... Obtaining nutritious food is becoming increasingly difficult due to the growing urban population and the degradation of soil, water, and air from mechanized and industrialized agricultural techniques. More than half the global population resides in urban areas, with not enough surrounding agricultural land to meet food requirements. Food traveling long distances, an average of 1020 miles, has resulted in increased food miles for the average food item in the United States of America, representing wasted resources. The novel GREENBOX technology was invented in response to increasing pressures on food security. Previous studies conducted on GREENBOX technology assessed the technical feasibility of utilizing Lettuce Lactuca sativa ‘Rex Butterhead’. We at the APS Laboratory for Sustainable Food at Florida Gulf Coast University assessed the technical feasibility of growing different leafy green vegetable crops. GREENBOX technology consists of thermally insulated climate-controlled enclosures, an artificial lighting source, a soilless cultivation method (hydroponics), and environmental control modules. We assembled two GREENBOX units to assess the environmental conditions and growth performance of Brassica rapa var. chinensis ‘Li Ren Choi’, Spinach Spinacia oleracea ‘Auroch’, Arugula Eruca sativa ‘Astro’, and Mizuna Brassica Brassica rapa var. japonica. Plugs were cultivated and then transplanted in a randomized manner to the nutrient film technique (NFT) channels, subsequently grown for 30 days to full bloom and ready for harvest. Fertigation was carried out using a standard concentration nutrient solution. Crops were arranged in twelve blocks of four species each. We collected environmental data including daily light integral (DLI, mol/m<sup>2</sup>∙d), temperature (˚C), relative humidity (%), and vapor pressure deficit (VPD, kPa). Collected biomass data included wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (mg/cm<sup>2</sup>). We then derived the Specific Leaf Area (SLA, cm<sup>2</sup>/g). Descriptive statistics were utilized to understand the differences in biomass parameters between the four crops grown. We also compared the performance parameters of our crops with existing peer-reviewed literature and found it superior, if not comparable to commonly found industrial output. We determined that all crops grew to full bloom, demonstrating that GREENBOX technology may be used to grow a variety of different leafy green vegetable crops. 展开更多
关键词 Controlled Environment Agriculture Food Insecurity GREENBOX HYDROPONICS LETTUCE
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Effectiveness of Soil Conservation Methods in Preventing Red Soil Erosion in Southern China 被引量:2
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作者 ZHANG Guo-Hua XIE Chong-Bao +1 位作者 PI Xiao-Yu ZUO Chang-Qing 《Journal of Mountain Science》 SCIE CSCD 2015年第5期1281-1291,共11页
Rainfall, runoff(surface runoff and interflow) and soil loss were recorded from 2002 to2005 in an experiment with four treatments on sloping red soil land in southern China. Treatments consisted of bare sloping ground... Rainfall, runoff(surface runoff and interflow) and soil loss were recorded from 2002 to2005 in an experiment with four treatments on sloping red soil land in southern China. Treatments consisted of bare sloping ground(control check, CK),interplanting with soybean in spring or radish in autumn(I), level terrace(i.e., grass planted on the riser and bunds built at the edge of a bench terrace)(II), and level terraces of orchards with Bahia grass planted on the riser(III). The surface runoff and erosion in treatment II and III during the four years were low despite the occurrence of potentially erosive rains. By contrast, the CK plot had both the highest surface runoff coefficient and the highest sediment yield among all the plots. The surface runoff and soil erosion of the CK plot significantly differed from that of the treatment plots(p < 0.05). Additionally,Significant differences between the interflow of the CK plot and that of the treatment plots was found from April to August(p < 0.05). However, no significant differences between the CK and treatment plots were found from January to March and September to December. The order of the plots in terms of surface runoff coefficients and soil losses was: CK > I > III > II, whereas their order in terms of interflow was II > III > I > CK. The effects of treatment II were excellent, indicating that level terrace(i.e., grass planted on the riser and bunds built at the edge of a bench terrace) can be an excellent practice for soil and water conservation on sloping red soil land. Soil loss in southern China can be reduced through the widespread use of this approach. 展开更多
关键词 侵蚀性降雨 土壤流失 红壤坡地 华南 保护措施 地表径流量 水平梯田 台地边缘
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Preliminary Study on Biological Control of Cyclops of Zooplankton in Drinking Water Source 被引量:10
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作者 刘冬梅 崔福义 +1 位作者 林涛 张立秋 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第2期184-190,共7页
An ecological project called fish biomanipulation, other than the conventional fishery culture technique, was put forward in this paper for the excess propagation control of Cyclops. The control effects on Cyclops of ... An ecological project called fish biomanipulation, other than the conventional fishery culture technique, was put forward in this paper for the excess propagation control of Cyclops. The control effects on Cyclops of four species of fish were investigated experimentally at stocking density of 30 g per cubic meter of water. The experimental results showed that the food habit of the fish had significant influence on the biological control of Cyclops. The propagation of Cyclops could be controlled effectively and also the water quality was improved simultaneously by stocking the filter-feeding fishes, such as silver carp and bighead carp. Whereas, herbivorous Ctenopharyngodon idellus and omnivorous Cyprinus carpio had no obvious biological effects on controlling the growth of Cyclops and restoring water quality. The results further proved that under condition of proper poly-culture density of silver carp and bighead carp, the number of Cyclops might be controlled at very low level and the eutrophication might be abated by removing the nutrients from water body. 展开更多
关键词 剑水蚤 浮游动物 超营养作用 生物控制 饮食习惯 鱼类 过度繁殖控制 饮用水水源 饮水安全
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An Ecologically Oriented Operation Strategy for a Multi-Reservoir System: A Case Study of the Middle and Lower Han River Basin, China 被引量:5
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作者 Hao Wang Xiaohui Lei +4 位作者 Denghua Yan Xu Wang Shuyue Wu Zhengjie Yin Wenhua Wan 《Engineering》 2018年第5期627-634,共8页
水库群的建设和调度改变了河流的自然流态,对河流生态系统造成了不利影响。本文提出了一种面向生态的水库群调度策略,将河流内不同生态功能所需的生态流量整合到水库群联合调度中,以实现生态流量需求和人类用水需求之间的均衡。该策略... 水库群的建设和调度改变了河流的自然流态,对河流生态系统造成了不利影响。本文提出了一种面向生态的水库群调度策略,将河流内不同生态功能所需的生态流量整合到水库群联合调度中,以实现生态流量需求和人类用水需求之间的均衡。该策略耦合了常规优化调度方案和一系列实时生态调度方案。在人类用水需求与生态流量需求冲突较小的时段,水库群调度在保障河流最小流量的前提下采用常规优化调度方案,最大限度地提高人类用水效益。在水库引发的水文改变对河流关键生态功能产生严重影响的时期,水库群调度采用实时生态调度方案,调整下泄流量,从而满足河流生态流量需求。该策略被应用于位于中国汉江中下游流域的一个大型水库群中。模拟调度结果表明,实时生态调度方案保证了河流关键生态功能的生态流量需求,其对人类用水效益的不利影响可通过常规优化调度方案得到部分补偿。本文提出的面向生态的水库群调度策略丰富了考虑生态流量需求的水库群联合调度的理论应用。 展开更多
关键词 水库 水资源 自然流态 河流
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Validated Method for the Detection of Three Phthalates Derived from Marine Invertebrates
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作者 D. Avisar A. Kaplan +3 位作者 G. Ronen-Eliraz G. Vered N. Shenkar I. Gozlan 《American Journal of Analytical Chemistry》 2019年第10期445-458,共14页
This study represents, detailly, the validated method for the extraction and quantification of widespread phthalic acid esters (PAEs) bis(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP) and di-n-octyl phtha... This study represents, detailly, the validated method for the extraction and quantification of widespread phthalic acid esters (PAEs) bis(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP) and di-n-octyl phthalate (DnOP) from solitary ascidians collected from a marine environment. The extraction was based on a pressurized liquid extraction method, using n-hexane as the solvent to extract the target PAEs from dry biological tissues, and was performed in an accelerated solvent extraction instrument. The average recovery of 89.2% was obtained from samples subjected to a pressure of ~1500 psi and 120°C in two 10-min cycles. GC-MS was used for quantification, conducted in single-ion monitoring mode. Following careful and rigorous cleanup procedures to prevent cross-contamination from laboratory glassware, PAE standards showed signals with good specificity. The obtained limits of detection were 130, 122 and 89 ng/g for DEHP, DBP and DnOP, respectively. Accordingly, the calculated limits of quantification were 394, 370 and 270 ng/g for DEHP, DBP and DnOP, respectively. The obtained linearity ranged from 5.4 to 269 ng/ml (equivalent to 135 - 6725 ng/g dry weight), with R2 ≥ 0.998. Concentrations in the range of 200 to 9000 and 400 to 5000 ng/g sample dry weight, for DEHP and DBP, respectively, were obtained from the ascidians. No DnOP was detected in any of the samples. These results indicate that the method presented in this study is applicable for detection of low and trace concentrations of the target PAEs in samples collected from a marine organism, which can serve as a bioindicator of plastic contamination. 展开更多
关键词 PHTHALATE Plastic CONTAMINATION BIOINDICATOR GC-MS ASE Marine INVERTEBRATE
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Investigation on Water Jet Treated Polyester/cotton Blended Cambric
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作者 黄故 《Journal of Donghua University(English Edition)》 EI CAS 2004年第1期104-108,共5页
Analytical examination was made to ascertain the effect of the high pressure water flow on the fabric properties.Polyester/cotton blended cambric was spurted by high pressure water flow. Fabric properties such as hand... Analytical examination was made to ascertain the effect of the high pressure water flow on the fabric properties.Polyester/cotton blended cambric was spurted by high pressure water flow. Fabric properties such as handle,thickness, tensile strength , stiffness and air permeability after the water treatment were investigated. 展开更多
关键词 细薄布 高压水喷射 水处理 织物性能 聚酯棉花混纺品
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Evaluation of the Contribution of Aerosols in the Contamination of the Environment in the Greater Casablanca
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作者 HADER Khadija Lahcen BAHI 《Journal of Earth Science and Engineering》 2016年第2期110-113,共4页
关键词 环境污染 气溶胶 评价 空气质量 污染损害 工业发展 就业机会 大城市
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Atmospheric Pollution due to Road Traffic Case of the Greater Casablanca Region
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作者 HADER Khadija Lahcen BAHI 《Journal of Earth Science and Engineering》 2017年第1期51-54,共4页
关键词 大气污染 道路交通 挥发性有机化合物 废气排放量 二氧化硫 二氧化碳 悬浮颗粒 环境温度
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The Contribution of the GIS and the Principal Component Analysis in the Study of the Cement’s Dusts Impact on the Top Soils in the Central Part of the Oujda-Taourirt Corridor (Eastern Morocco)
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作者 Mohamed El Kharmouz Mohamed Sbaa Sanae Saadi 《Open Journal of Air Pollution》 2013年第4期100-106,共7页
Cement dust pollution is one of the sources of atmospheric pollution. The main impacts of the cement activity to the environment are the broadcasts of dusts and gases. The objective of this study is to determine the e... Cement dust pollution is one of the sources of atmospheric pollution. The main impacts of the cement activity to the environment are the broadcasts of dusts and gases. The objective of this study is to determine the effects of cement dust pollution on physico-chemical characteristics of the soil at the vicinity of the cement factory in Oujda-Taourirt corridor (Eastern Morocco) using Principal component analysis (PCA) and geographical information system (GIS). Forty one (41) surface soils (0 - 3 cm) were collected from the six rural townships surrounding the cement factory. The collected soil samples were analyzed for their chemical properties (CaO, Al2O3, Fe2O3, K2O, MgO, SO3 and SiO2) as well as their pH and Electric Conductivity. The results of the analysis showed that the dusts emitted by the cement plant are especially basic and contain a high free lime (43.03% CaO). The principal component analysis applied on the 41 superficial soil samples, allows deducting that the free lime and the sulfur oxide are the tracer elements of this form of pollution. Furthermore, the spatial projection of the factor scores of the principal component analysis using the geographical information system permits us to determine the spatial distribution of more polluted areas of soils as well as to estimate their impact at a zone of 2.5 km of beam around the factory. 展开更多
关键词 Cement DUST Soil Spatial Distribution PHYSICO-CHEMICAL Analysis PCA
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Some Characteristics of Cumulus Convection over the Tibetan Plateau
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作者 段廷扬 Elmar R.Reiter 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第1期87-97,共11页
The diagnostic model of the cumulus convection proposed by Yanai et al. (1973) was applied to the atmosphere over the Tibetan Plateau, and used to estimate the vertical mass flux, entrainment and detrainment, excess t... The diagnostic model of the cumulus convection proposed by Yanai et al. (1973) was applied to the atmosphere over the Tibetan Plateau, and used to estimate the vertical mass flux, entrainment and detrainment, excess temperature and moisture, liquid water content, and condensation and precipitation rates of highland cloud clusters. The results illustrated that in clouds over the Tibetan Plateau, the water vapor condensation rate, liquid water content, and efficiency of the rain generation process are less than those in the tropics (represented by the Marshall Islands region). Therefore, the condensational latent heat released over the Tibetan Plateau, overall, is much smaller than that in the tropics. The water vapor and liquid water detrainment from shallow nonprecipitating cumulus clouds, and their entrainment into deep cumulus clouds, serve as a growing mechanism for the deep precipitating cumulus towers over the Tibetan Plateau. It should be noted that there is a stronger detrainment of liquid water from cumulus clouds and a stronger re-evaporation rate in environment. The process of the condensation-detrainment-re-evaporation-cnlrainmcnt is repeatedly in progress. It would play an important role in maintaining of cumulus convection on the condition that the supply of moisture is not plentiful over the Tibetan Plateau.The analyses also showed that the cloud mass flux Mc over the Tibetan Plateau is less, and the large-scale average upward motion is much less than those over the Marshall Islands. Stronger compensating downward motion in the cloud environment over the Tibetan Plateau, responsible for the area's strong environmental heating rate Was revealed, and would link to the stability of the South Asian High in summer. 展开更多
关键词 Some Characteristics of Cumulus Convection over the Tibetan Plateau OVER
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Evaluation of Aluminum Levels in Drinking Water of Nouakchott
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作者 Brahim Ahmed Dick Mohamed Bouna Ammar +2 位作者 Yahya Maham Ould Sidi HYLearoussy Mohamed Elkory Cheikh 《Journal of Pharmacy and Pharmacology》 CAS 2021年第5期210-213,共4页
The drinking water of Nouakchott,the capital of Mauritania,comes from the Senegal River.The current water treatment is done with aluminum sulfate.In order to monitor the aluminum content,from September 2015 to August ... The drinking water of Nouakchott,the capital of Mauritania,comes from the Senegal River.The current water treatment is done with aluminum sulfate.In order to monitor the aluminum content,from September 2015 to August 2016,three samples were taken monthly for each water source:pretreated water(from Beni Naji treatment station),treated water(from PK17 treatment station)and the water tower.The analysis results of the aluminum content of the treated water(full treatment)and pretreated water(first treatment)showed that the aluminum content of all samples was between 0.03 mg/L and 0.09 mg/L,with an average value of 0.07 mg/L.The World Health Organization stipulates that the normal content of aluminum between 0.1 mg/L and 0.2 mg/l.In the course of the study,the changes of aluminum content in samples from different places were observed.This change can be explained by coagulation-flocculation of aluminum sulfate.The aluminum content of the samples met the World Health Organization standards for drinking water. 展开更多
关键词 EVALUATION WATER TREATMENT ALUMINUM Nouakchott Mauritania.
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Germany Under Treaty:German reactions to the Treaty of Versailles after World War I
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作者 王天予 《神州》 2016年第17期201-202,共2页
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Controlled Environment Agriculture and Its Ability to Mitigate Food Insecurity
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作者 Aubrey Lynn Garcia Mya Alexandria Catherine Griffith +4 位作者 George Paul Buss Xiusheng Yang John L. Griffis Sarah Bauer Ankit Kumar Singh 《Agricultural Sciences》 CAS 2023年第2期298-315,共18页
The research objective of this review is to discuss the rationale that led to the development of Controlled Environment Agriculture (CEA) and investigate this agricultural approach as a potential solution to mitigate ... The research objective of this review is to discuss the rationale that led to the development of Controlled Environment Agriculture (CEA) and investigate this agricultural approach as a potential solution to mitigate the increased pressures on food security. It describes the need for urban cultivation systems using controlled environments and how they can be harnessed to address pressures facing food security. The factors that have contributed to the growth of CEAs, education, environmental justice, and the advantages and disadvantages of growing crops in CEAs in urban areas will be discussed. The article reviews global urban cultivation systems using controlled environments, by identifying the technologies needed to establish them. The practice of CEA is being increasingly adopted worldwide and we describe urban agriculture and compare it with traditional growing systems. Indoor farming systems that integrate into existing urban infrastructure such as vertical farming and plant factories using CEAs are discussed. Indoor farming gives urban areas enhanced access to food sources, but the cost is high, however decreasing due to recent technological advances. The current review extends the literature by incorporating recent research on the topic of agriculture in urban areas and food security. This review seeks to provide additional information regarding the viability of CEA in urban areas. 展开更多
关键词 Controlled Environment Agriculture Environmental Education Environmental Justice Food Deserts Urban Agriculture
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Comparison of Remolded Shear Strength with Intrinsic Strength Line for Dredged Deposits 被引量:9
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作者 邓东升 《China Ocean Engineering》 SCIE EI 2007年第2期363-369,共7页
Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on th... Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on the intrinsic strength line is different from the remolded undrained shear strength that is an important parameter for design and construction of land reclamation. The void index is used in this study for normalizing the remolded strength behavior of dredged deposits. A quantitative relationship between remolded undrained shear strength and void index is established based on extensive data of dredged deposits available from sources of literature. Furthermore, the normalized remolded undrained shear strength is compared with intrinsic strength line. The comparison result indicates that the ratio of undrained shear strength on the intrinsic strength line over remolded undrained shear strength increases with an increase in applied consolidated stress. 展开更多
关键词 consolidation stress dredged deposits intrinsic strength line remolded shear strength void index
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Hillslope soil erosion and runoff model for natural rainfall events 被引量:3
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作者 Zhanyu Zhang Guohua Zhang +1 位作者 Changqing Zuo Xiaoyu Pi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第3期277-283,共7页
By using the momentum theorem and waterbalance principle, basic equations of slope runoff were derived, soil erosion by raindrop splash and runoff were discussed and a model was established for decribing hillslope soi... By using the momentum theorem and waterbalance principle, basic equations of slope runoff were derived, soil erosion by raindrop splash and runoff were discussed and a model was established for decribing hillslope soil erosion processes. The numerical solution of the model was obtained by adopting the Preissmann format and considering the common solution-determining conditions, from which not only the runoff and soil erosion but also their processes can be described. The model was validated by ten groups of observation data of Soil Conservation Ecological Science and Technology Demonstration Park of Jiangxi Province. Comparisons show that the maximum relative error between simulation and experimental data is about 10.98% for total runoff and 15 % for total erosion, 5.2% for runoffprocess and 6.1% for erosion process, indicating that the model is conceptually realistic and reliable and offers a feasible approach for further studies on the soil erosion process. 展开更多
关键词 Overland flow Raindrop splash RUNOFF Erosion process Numerical simulation
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