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991.
人参菜开发及其利用初探 总被引:1,自引:0,他引:1
周安刚 《湖南环境生物职业技术学院学报》2009,15(1):27-29
随着时代的发展,人们越来越重视吃、穿、住、行,其中以吃为最。原有的蔬菜品种已经不能满足人们的追求,越来越多营养丰富的野菜都通过驯化、改良进入了人们的视野,人参莱就是其一,该文简要叙述人参莱的特征、营养成分、价值。着重介绍其栽培技术,以供参考.参5. 相似文献
992.
Farooq S Hashmi I Qazi IA Qaiser S Rasheed S 《Environmental monitoring and assessment》2008,140(1-3):339-347
The present study was undertaken to examine the drinking water quality of Rawal Treatment Plant, Rawalpindi and its distribution
network by collecting samples from eight different locations. The aim was to determine potential relationship between the
presence of microorganisms and chlorine residual in the distribution network. Quantification of chlorine residual, turbidity,
standard plate count (SPC), fecal and total coliforms by Most Probable Number (MPN) was performed. Three different forms of chlorine were measured at each sampling station such
as free chlorine, residual chlorine, chloramines and total chlorine residual. A critical evaluation of data presented indicated
that pH generally ranged from 7.02–7.30; turbidity varied from 0.34–2.79 NTU; conductivity fluctuated from 359–374 μS/cm;
and TDS values were found to be ranging between 180–187 mg/l. Station # 7 was found to be most contaminated. The value of total chlorine was found to be 0.86 to1.7 mg/l at Station # 3 and 6, respectively. Highest standard plate count was 62 CFU/ml at Station # 7. Total
coliforms were less than 1.1 MPN/100 ml at almost most of the stations except at Station # 3 where it was found to be greater than 23.0 MPN /100 ml. Overall aim of this study is to create awareness about contamination
of drinking water in the water distribution networks and to make recommendations to provincial agencies such as EPA, CDA and
WASA that regular monitoring should be carried out to ensure that the chlorine residual is available at consumer end. 相似文献
993.
The role of optimality in characterizing CO2 seepage from geologic carbon sequestration sites 总被引:1,自引:0,他引:1
Andrea Cortis Curtis M. Oldenburg Sally M. Benson 《International Journal of Greenhouse Gas Control》2008,2(4):640
Storage of large amounts of carbon dioxide (CO2) in deep geologic formations for greenhouse-gas mitigation is gaining momentum and moving from its conceptual and testing stages towards widespread application. In this work we explore various optimization strategies for characterizing surface leakage (seepage) using near-surface measurement approaches such as accumulation chambers and eddy covariance towers. Seepage characterization objectives and limitations need to be defined carefully from the outset especially in light of large natural background variations that can mask seepage. The cost and sensitivity of seepage detection are related to four critical length scales pertaining to the size of the: (1) region that needs to be monitored; (2) footprint of the measurement approach, and (3) main seepage zone; (4) region in which concentrations or fluxes are influenced by seepage. Seepage characterization objectives may include one or all of the tasks of detecting, locating, and quantifying seepage. Each of these tasks has its own optimal strategy. Detecting and locating seepage in a region in which there is no expected or preferred location for seepage nor existing evidence for seepage requires monitoring on a fixed grid, e.g., using eddy covariance towers. The fixed-grid approaches needed to detect seepage are expected to require large numbers of eddy covariance towers for large-scale geologic CO2 storage. Once seepage has been detected and roughly located, seepage zones and features can be optimally pinpointed through a dynamic search strategy, e.g., employing accumulation chambers and/or soil-gas monitoring. Quantification of seepage rates can be done through measurements on a localized fixed grid once the seepage is pinpointed. Background measurements are essential for seepage detection in natural ecosystems. Artificial neural networks are considered as regression models useful for distinguishing natural system behavior from anomalous behavior suggestive of CO2 seepage without need for detailed understanding of natural system processes. Because of the local extrema in CO2 fluxes and concentrations in natural systems, simple steepest-descent algorithms are not effective and evolutionary computation algorithms are proposed as a paradigm for dynamic monitoring networks to pinpoint CO2 seepage areas. 相似文献
994.
Persistent bioaccumulative and toxic (PBT) pollutants are chemical contaminants that pose risks to ecosystems and human health.
For these reasons, available tissue contaminant data from the US EPA Environmental Monitoring and Assessment Program’s National
Coastal Assessment were examined to estimate to what areal extent PBTs are found in US estuarine resources. The data document
composite, whole-body tissue chemical concentrations for 736 sampling sites across Northeast, Southeast, Gulf of Mexico, and
West Coast estuaries. Tissue chemical concentrations were compared to US EPA non-cancer risk guidelines for recreational fishers,
because of a lack of ecological guidelines for these chemical concentrations. Samples were analyzed for 23 PAH compounds,
21 PCB congeners, 6 DDT derivatives and metabolites, 14 chlorinated pesticides (other than DDT) and 13 metals, including mercury.
Total PCBs were found to exceed recreational fisher guidelines most frequently (31% of samples evaluated), followed by mercury
(29%), total PAHs (21%), and DDT and its metabolites, DDD and DDE (11%). Toxaphene, cadmium and dieldrin were found but in
fewer than 1% of the samples. 相似文献
995.
Pan. K. Marhavilas D.E. Koulouriotis 《Journal of Loss Prevention in the Process Industries》2008,21(6):596-603
The risk estimation presumably is the most crucial part of the entire procedure of assessing hazards/unsafe situations in the work, and especially in the industries’ and constructions’ worksites, where the working conditions are unstable. We can consider the risk as a quantity, which can be estimated and expressed by a mathematical relation, under the help of real accidents’ data. The aim of this work is quadruplicate: (a) the development, elaboration and explanation of two new quantitative risk-assessment techniques, (b) the improvement of specific points of other scientific works, as far as concerns quantitative risk estimation, (c) the application of these techniques on an industrial productive procedure (as a case study) and (d) the comparison of their outcome risk-estimation results. Particularly, we develop and analyze the theoretical background of the two techniques, which we call as “proportional technique” and “decision matrix technique”, and apply them on an aluminum extrusion industry's worksite, which is situated in Greece, by using real data of potential sources of hazards, recorded by safety managers, during the 5.5-year time period of 1999–2004. Comparing the results of the two quantitative risk-assessment techniques, we infer that they are compatible. Therefore, the most important hazard source in the aluminum industry is the “squeezing and hits by dropping objects (transported by derricks)”, and imposes that immediate suppressive measures must be taken place to abolish the danger source. 相似文献
996.
“三软”煤层注水封孔技术的试验研究 总被引:1,自引:1,他引:0
在分析“三软”煤层封孔特性的基础上 ,选择了合适的封孔方法 ,试验研究了Bimbar1型封孔器封孔技术 ,并对封孔器应用中的问题进行了讨论 ,设计了一种与之配套使用的单向自动截止阀 ,成功地实现了“三软”煤层注水封孔 ,可供类似条件的煤层实施该技术参考。 相似文献
997.
998.
999.
M. Yu. Semenov T. V. Khodzher V. A. Obolkin V. M. Domysheva L. P. Golobokova N. A. Kobeleva O. G. Netsvetaeva V. L. Potemkin R. Van Grieken N. Fukuzaki 《Chemistry and Ecology》2006,22(1):1-11
Data from 3-year-long observations on the chemical composition of precipitation, atmospheric gases, aerosols, soils, and surface waters at three monitoring stations in the Baikal region are presented. The stability of terrestrial ecosystems and surface waters to acidification has been estimated quantitatively. It has been shown that, unlike soils, surface waters of the Baikal watershed are more sensitive to acid deposition. The permissible acidity load for soils and surface waters of the territory varied from 0.30 to 20.00 keq ha-1 yr-1, whereas the maximal contemporary acidity load attains 0.50 keq ha-1 yr-1. 相似文献
1000.
The inorganic anion pollution of the New Calabar River surface water was investigated. Results showed seasonal variations
in the inorganic anion levels. Water parameters such as sulfite, nitrate, phosphate, and alkalinity showed significantly higher
values in the rainy season than in the dry season. Dissolved oxygen, pH, sulfide, sulfate, ammonia, and nitrite showed no
significant differences between their rainy and dry season levels. Upstream-downstream changes were shown by conductivity,
total dissolved solids, chloride, salinity, and temperature. Exceptions occurred in the nitrite levels, where the effect was
minimal. Although the concentrations of some anions analyzed fell within internationally acceptable limits, the New Calabar
River water is, in the main, polluted with inorganic anions and may be unacceptable for potable and industrial uses without
treatment. 相似文献