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分光光度法测定丁烯水合工艺水的重质物含量 被引量:1
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作者 李彬 赵彦龙 苏芳云 《工业水处理》 CAS CSCD 北大核心 2010年第1期63-64,76,共3页
建立了一种采用分光光度法测定丁烯水合工艺水的重质物含量的方法。以蒸馏水为参比,在波长400nm处得到了重质物含量与吸光度的线性拟合方程为C=1.16208A+0.0011,其线性相关系数达到0.9996。该方法操作简单快捷,分析精度高,检测限低,能... 建立了一种采用分光光度法测定丁烯水合工艺水的重质物含量的方法。以蒸馏水为参比,在波长400nm处得到了重质物含量与吸光度的线性拟合方程为C=1.16208A+0.0011,其线性相关系数达到0.9996。该方法操作简单快捷,分析精度高,检测限低,能够满足甲乙酮装置的生产需要。 展开更多
关键词 分光光度法 丁烯水合 含量 量法
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关于易挥发原油物性实验分析标准的几点讨论 被引量:9
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作者 妥宏 吕道平 +2 位作者 汤勇 李遇江 刘伟洲 《特种油气藏》 CAS CSCD 2006年第6期87-90,共4页
通过对新疆准噶尔盆地卡因迪克油田多个易挥发性油藏流体样品的PVT相态实验的测试研究认为,石油天然气行业标准SY/T 6435—2000《易挥发原油物性分析方法》中对易挥发原油的实验测试方法和物性计算方法存在不适应性,其中挥发性油藏原始... 通过对新疆准噶尔盆地卡因迪克油田多个易挥发性油藏流体样品的PVT相态实验的测试研究认为,石油天然气行业标准SY/T 6435—2000《易挥发原油物性分析方法》中对易挥发原油的实验测试方法和物性计算方法存在不适应性,其中挥发性油藏原始地层流体中的重质含量计算、饱和压力的确定、单次闪蒸实验以及定容衰竭实验等内容和方法值得商榷,并提出了具体的改进方法。该研究对于正确认识易挥发性原油流体的相态特征,有效地指导该类特殊油藏的开发具有重要意义。 展开更多
关键词 挥发性原油 重质含量 饱和压力 体积系数 准噶尔盆地
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Investigation of Heavy Metal Contents in Traditional Chinese Herbal Medicine Peristrophe roxburghiana Collected from Northwest of Guangxi 被引量:2
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作者 刘旭辉 李容 +2 位作者 郭俊 罗志勇 覃勇荣 《Agricultural Science & Technology》 CAS 2016年第12期2751-2756,2762,共7页
Objective] This study was conducted to evaluate the product quality and safety of Peristrophe roxburghiana_ col ected from different places in Hechi City, northwest of Gunagxi, so as to provide basic data for further ... Objective] This study was conducted to evaluate the product quality and safety of Peristrophe roxburghiana_ col ected from different places in Hechi City, northwest of Gunagxi, so as to provide basic data for further development and uti-lization of the characteristic plant resource P. roxburghiana. [Method] Contents of 9 kinds of heavy metals including Cd, Mn, Pb, Zn and Cu in the herb were deter-mined by the method of wet digestion-flame atomic absorption spectrophotometry and atomic fluorescence spectrometry, respectively. [Results] Heavy metal contents of Cd, Mn, Pb, Fe, Cu, Zn, As, Hg and Se were 1.62-17.25, 8.93-142.53, 4.37-18.43, 103.7-242.81, 2.55-5.35, 85.40-146.30, 0.07-0.54, 0.00-0.08 and 0.00-0.47 mg/kg, respectively. According to the national food safety standards and Green Trade Standards of lmporting &amp; Exporting Medicinal plants &amp; Preparations, the heavy metal contents of the P. roxburghiana_samples col ected from different coun-ties in Hechi City exceeded standards or at the critical values. Among which, Cd, Pb and Zn contents of the samples are seriously higher than the standards. [Con-clusion] Therefore, the impact of soil heavy metal pol ution on the safety of edible plants in the northwest of Guangxi should be highly concerned. 展开更多
关键词 Northwest of Guangxi Traditional Chinese herbal medicine Peristro-pheroxburghiana Product quality and safety Heavy metal content
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Analysis and Evaluation of Heavy Metal Environmental Quality of Irrigation Water in Vegetable Farmlands of Shandong Province 被引量:7
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作者 刘苹 魏建林 +3 位作者 于淑芳 杨力 Jian-lin Shu-fang 《Agricultural Science & Technology》 CAS 2010年第5期165-167,186,共4页
[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigatio... [Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigation water of main vegetable farmlands of Shandong Province were investigated by randomly sampling,and the environmental quality conditions of these heavy metals were evaluated by methods of single quality index and complex quality index. [Result] The results showed that the average contents of heavy metals in irrigation water of Shouguang,Laiyang,Jinxiang and Zhangqiu were all far lower than the limit values prescribed by 'Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products' (HJ332-2006),and no heavy metal was found beyond the limit value in every sample. The single quality indices of the 7 elements in the studied 4 places were all lower than 0.5. The comprehensive quality index of the seven elements was 0.317 8 in Shouguang,0.320 4 in Laiyang,0.232 6 in Jinxiang,and 0.260 7 in Zhangqiu. The environmental quality of irrigation water in the studied four places were all set at the first class. [Conclusion] The environmental quality of irrigation water in the 4 places belonged to clean level and were fit for the plantation of no pollution vegetables. 展开更多
关键词 Vegetable irrigation water Heavy metal Environmental quality
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Assessment of nitrogen maintenance requirement in juvenile Black Porgy Acanthopagrus schlegeli
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作者 朱秋华 钱国英 +1 位作者 高有领 汪财生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期63-68,共6页
Nitrogen balance method and nitrogen-free diet were used in this study to determine nitrogen maintenance requirement (NM) and nitrogen maintenance requirement per unit metabolism body weight (NM’) of black porgy Acan... Nitrogen balance method and nitrogen-free diet were used in this study to determine nitrogen maintenance requirement (NM) and nitrogen maintenance requirement per unit metabolism body weight (NM’) of black porgy Acanthopagrus schlegeli. Fish with body weight (BW) of 50, 80, 120, 160 and 200 g were fed by the diets containing three graded levels of crude protein (380, 420 and 460 g/kg). The results from nitrogen balance experiment showed that the amount of nitrogen deposition varied from 0.15 to 0.31 mg/g BW per day, accounting for 12.2% to 21.1% of nitrogen intake. The amount of fecal nitrogen excretion varied from 0.21 to 0.32 mg/g BW per day, accounting for 16.3% to 21.6% of nitrogen intake. The endogenous nitrogen excretion, a main part of nitrogen consumption varied from 0.79 to 0.97 mg/g BW per day, accounting for 63.3 % to 68.0% of nitrogen intake. Positive correlation was found between NM and body weight, while a negative correlation was found between NM of unit body weight and the growth duration. No significant differences (p>0.05) were found in NM’ among different growth stages. The average of NM’ was 0.485 7mg/g per day. The results from nitrogen-free diet experiment showed that a negative correlation between NM and feed intake of nitrogen-free diet. NM increased with the decrease of feed intake of fish. The average of NM was 0.482 9 mg/g BW per day that was close to 0.483 8 mg/g BW obtained from fish with 120 g BW in nitrogen balance experiment. The nitrogen balance method is recommended to be a better method for determining NM in consideration of fish stress and result stability. This study also provides a calculated result of the protein content in diets, which is necessary for maintaining fish body protein at different growth stages. The calculation was based on the amount of nitrogen required for maintaining body protein per kg BW. 展开更多
关键词 Acanthopagrus schlegeli nitrogen balance nitrogen-free diet nitrogen maintenancerequirement protein contain levels
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Water Analysis for Heavy Metals Content in Selected Boreholes in Port Harcourt Metropolis (A Case Study during 2010-2011) 被引量:1
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作者 Kalagbor Ihesinachi Appolonia Mgbodom-Okah Chidinma Juliet 《Journal of Environmental Science and Engineering(A)》 2013年第7期418-426,共9页
Underground water (Borehole) has been the main alternative source of drinking water for most communities in my country. Previous studies have revealed high levels of contamination. The origin of which can be attribu... Underground water (Borehole) has been the main alternative source of drinking water for most communities in my country. Previous studies have revealed high levels of contamination. The origin of which can be attributed to geochemical processes, combustion of fossil fuels, mining and anthropogenic activities. Most borehole water and well water in local communities of Nigeria are not safe for drinking due to heavy industrial and environmental pollution. This study was undertaken to assess the quality in some selected boreholes in the Port Harcourt metropolis for a period of two years. Borehole water samples were randomly collected from thirteen boreholes in a local community in plastic bottles (100 mL) in the months of September for the years of study (2010 & 2011). Four out of the seven heavy metals analyzed were found to be present in the first year of study. These were Fe, Cu, Mn and Zn. In the second year of study, Pb, Cr, Fe and Co were not detected in all of the samples except Cu and Fe which were present in only two samples. Mn and Zn were found to be present in all of the samples for both years of study. 展开更多
关键词 GROUNDWATER BOREHOLE geochemical processes.
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Characterization of Humic System in Fertilizer Raw Materials
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作者 Ekaterina Filcheva Rossitza Ilieva +3 位作者 Kosnstantin Chakalov Todorka Popova Valentin Savov Mariana Hristova 《Journal of Agricultural Science and Technology(A)》 2017年第1期11-17,共7页
The aim of the study was to characterize humus system of natural and artificial products. Humus systems from leonardite, lignite biotransformed with Trichoderma sp. (Plantagra), plant materials after pyrolisis (cha... The aim of the study was to characterize humus system of natural and artificial products. Humus systems from leonardite, lignite biotransformed with Trichoderma sp. (Plantagra), plant materials after pyrolisis (charcoal) and composts are compared. Humus systems are characterized by Kononova-Belchikova's method, and heavy metals content was measured by atomic absorption spectroscopy (AAS). Humic acids from the International Humic Substances Society (IHSS) collection are the standards for humus substances quality of compared products. Data obtained for leonardite indicate that the studied substances from factory, Izmir, Turkey contain humic acids over 94%. Compared to the standard, heavy metals content in these materials demonstrate high amounts. Organic carbon content in the composts is very low compared to the leonardite materials and IHSS collection, where the heavy metals content is lower. Biotransformed lignite is characterized with lower content of organic carbon, but humic acids are with high degree of humification. Results obtained show that the fourth studied humus systems may be used in agriculture on base of the high humic acids content. It is recommended to measure heavy metals content before applying the materials in agriculture. 展开更多
关键词 COMPOST humic acid leonardite LIGNITE sewage sludge Trichoderma harzianum Trichoderma viride.
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Composition of Pig Manures and Wastewaters under the Gan Qing Fen System in China 被引量:1
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作者 R. Mendoza-Huaitalla E. Gallmann +2 位作者 K. Zheng X. J. Liu E. Hartung 《Journal of Agricultural Science and Technology(A)》 2011年第4X期514-518,共5页
A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2... A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2009. Samples were collected once a week based on the pig production cycle, namely gestation, farrowing, weaning and fattening. Analysis of nutrients and heavy metals were determined by means of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP). Total Nitrogen (TN) was determined by the Kjeldahl method. The main results showed that pig manures were characterized by high nutrients and heavy metals contents that might be due to the solid fraction separation from the liquid fraction under the gan qing fen manure management system. Further, piggery wastewaters were characterized by very low concentrations of nutrients and heavy metals as result of their dilution with flushing water mainly used for cleaning the pigsties. Manure and wastewaters samples from weaning pigs contained the highest concentrations of nutrients and heavy metals that could be due to high supplementation rates of these minerals in the weaner diets. In general, it seems that the manual daily collection of pig manures in the gan qing fen system is an efficient practice in order to maintain nutrient contents in pig manures but the use of flushing water should be reduced as it can lead to further environmental pollution. 展开更多
关键词 China gan qing fen MANURE WASTEWATER pig farm.
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The Effect of Salinity on Growth, Dry Weight and Lipid Content of the Mixed Microalgae Culture Isolated from Glagah as Biodiesel Substrate
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作者 Eko Agus Suyono Winarto Haryadi +3 位作者 Muhammad Zusron Matin Nuhamunada Sri Rahayu Andhika Puspito Nugroho 《Journal of Life Sciences》 2015年第5期229-233,共5页
Microalgae use photosynthesis to convert solar energy into chemical energy, such as lipid and they can be a replacement for oil-based fuels. They are among the fastest growing plants in the world, and about 50% of the... Microalgae use photosynthesis to convert solar energy into chemical energy, such as lipid and they can be a replacement for oil-based fuels. They are among the fastest growing plants in the world, and about 50% of their weight is oil. This lipid oil can be used to make biodiesel. Unfortunately, there are only some of potential strains isolated from Indonesia and most of the biodiesel productions are usually using a single strain. Then, although they are rich of oils, their biomass productivity is still low. Salinity treatment can be used to increase their biomass as well as their lipid content. Therefore, the research aim was to study the effect of salinity on the growth, dry weight and lipid content of mixed microalgae isolated from Glagah, Yogyakarta. The mixed microalgae were cultured in 3NBBM medium with different salinities or types of water (sea water, brackish water, and fresh water). The cultures were incubated at light intensity 3,000 lux under dark:light exposure of 12:12 h for 7 days. The number of cells was counted every 24 h with a Haemocytometer, and the biomass was calculated based on the dry weight. The lipid content was measured on days 0, 3, and 7 using NR (Nile Red) staining, and then the amount of lipid was analyzed using a fluorescence microscope and measured with CellProfiler 2.0 software. The highest dry weight and lipid content were found in seawater medium, they accounted for 3.42 mg/mL and 13.58% at day 7, respectively. Whereas, the highest number of cells was found in freshwater medium, this was 9.8 × 10^6 cells/mL. 展开更多
关键词 SALINITY GROWTH dry weight lipid content.
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Exploration of Urinary Creatinine to Determine the Carcass and Its Protein Weight in Beef Cattle
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作者 A. Purnomoadi T. Wahyuningtyas E. Rianto 《Journal of Agricultural Science and Technology(A)》 2011年第8期1159-1161,共3页
This study was aimed to explore the use of creatinine as indicator to predict carcass and its protein weight in beef cattle. Eight Ongole crossbred cattle with initial body weight ranged at 133.5-228 kg and age of 6-1... This study was aimed to explore the use of creatinine as indicator to predict carcass and its protein weight in beef cattle. Eight Ongole crossbred cattle with initial body weight ranged at 133.5-228 kg and age of 6-18 months were used in this study. The cattle were fed Napier grass ad libitum and concentrate feeding for three months prior to be slaughtered. Concentrate feeding was consisted of rice bran and soybean meal which was provided to fulfill dry matter requirement at 2.1% of body weight (BW). The availability of creatinine for prediction indicator was done by evaluate the correlation between the amount of daily urinary creatinine and the carcass and its protein weight. Carcass and its protein weight were measured by slaughtering the cattle, and chemically analyzed for determining protein content of carcass. The results showed that creatinine excreted in urine have a strong correlation with the cattle body weight (r = 0.88), carcass weight (r = 0.67), body protein (r = 0.70) and carcass protein (r = 0.72). The conclusion of this study is creatinine excreted in urine have a strong relationship with the carcass and its protein, and therefore could be used to predict the carcass and its protein weight of beef cattle. 展开更多
关键词 Beef cattle CREATININE carcass weight carcass protein body weight
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Using Organic Matter and pH to Estimate the Bulk Density of Afforested/Reforested Soils in Northwest and Northeast China 被引量:7
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作者 CHEN Yue HUANG Yao SUN Wenjuan 《Pedosphere》 SCIE CAS CSCD 2017年第5期890-900,共11页
Regression models for predicting soil bulk density(BD) have usually been related to organic matter content, but it remains unknown whether soil acidity modifies this relationship, particularly for afforested/reforeste... Regression models for predicting soil bulk density(BD) have usually been related to organic matter content, but it remains unknown whether soil acidity modifies this relationship, particularly for afforested/reforested soils. We measured soil BD along with organic matter content and pH in an afforested/reforested area in Northwest and Northeast China. Using these measurements, we parameterized and validated three BD models: the Adams equation, and exponential and radical models. Model validation showed that the Adams equation failed to predict the BD of the afforested/reforested soils, producing a large overestimation. Incorporation of soil pH into the Adams equation significantly improved its performance. The exponential and radical models parameterized by the measured data simulated soil BD quite well, particularly when soil pH was incorporated. However, incorporation of soil texture variables into these models did not improve model performance compared with the pH-modified models. This led to the conclusion that the Adams equation, exponential, and radical models with pH modification are applicable to afforested/reforested soils with various acidities. 展开更多
关键词 Adams equation regression model soil bulk density soil organic carbon soil pH
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