共查询到20条相似文献,搜索用时 15 毫秒
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生物质能源与能源林业若干问题研究 总被引:1,自引:0,他引:1
概述了生物质能对未来能源发展的重要作用,对我国能源林业和灌木能源林的情况作了简要介绍,并重点提出了小球藻油的利用对生物质能开发的影响. 相似文献
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Lin Liu Ding Ma Huiying Chen Heng Zheng Mojie Cheng Yide Xu Xinhe Bao 《Catalysis Letters》2006,107(1-2):25-30
Zn/I2 was found to be a practical and effective catalyst for the transesterification of soybean oil with methanol. A study for
optimizing the reaction conditions such as the molar ratio of methanol to oil, the reaction time and the catalyst amount,
was performed. The highest conversion of 96% was obtained under the optimum conditions. Further, the effect of free fatty
acids and water in the soybean oil on the catalytic activity of the catalysts was also investigated. 相似文献
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高效氯氟氰菊酯对普通小球藻的毒性 总被引:1,自引:0,他引:1
[目的]通过高效氯氟氰菊酯在不同质量浓度下光合色素及SOD等生物量变化试验,了解高效氯氟氰菊酯对普通小球藻的毒性效应,为评价该药剂对水生生物的影响提供一定的理论依据。[结果]试验结果表明:高效氯氰菊酯对普通小球藻的抑制中浓度为105.71 mg/L,普通小球藻体内光合色素含量及SOD活力的随药剂质量浓度的变化均发生了变化。[结论]随着药剂处理质量浓度的增加,普通小球藻光合色素含量逐渐减少,SOD活力也随着药剂质量浓度的增加而急剧下降,且药剂对普通小球藻的毒性属于低毒。 相似文献
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小球藻处理养猪业沼液研究 总被引:3,自引:0,他引:3
利用不同浓度的沼液驯化小球藻(Chlorella vulgaris)得到耐高浓度沼液的优势藻株,然后用于处理养猪业沼液.结果表明:在曝气条件下培养小球藻能够高效利用沼液中的养分并使沼液得到高度净化.小球藻处理10 d后沼液中主要有机物指标:化学需氧量(COD)、悬浮物、氨氮(NH4+-N)、总磷(TP)分别下降到162.3、52、14.66 mg/L和7.57 mg/L,对应去除率分别为77.61%、91%、94.76%和80.03%.处理结果低于国标规定的集约化养猪业水污染物最高允许日排放质量浓度400、200、80 mg/L和8 mg/L. 相似文献
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Most common analytical methods in FA chemistry can be categorized as yielding either structure or quality indices. Quality
indices often describe components in fats and oils arising from processing, storage, and naturally occurring, nonfatty materials.
Common structure indices are the iodine value (IV), the saponification value, and the hydroxyl value. Although modern analytical
methods yield more detailed and reliable information, structure indices are still widely used. The IV, which indicates total
unsaturation, has even been included in some standards for industrial products such as biodiesel. However, the IV index is
too general to allow the correlation of physical and chemical properties with FA composition. The IV is treated in a theoretical
fashion regarding biodiesel- and oxidative stability-related issues. That the concept of IV as a structure index is unsatisfactory
is shown by the development of a quaternary composition diagram (QCD). The QCD demonstrates the derivation of a specific IV
from varying FA compositions. Improved correlations are possible among the structure indices. Alternative indices for the
IV are developed. Possible alternatives are the allylic position equivalent (APE) and the bisallylic position equivalent (BAPE)
which better relate structure and amount of common component FA in vegetable oils to observed properties. The APE and BAPE
indices are based on the number of reactive positions in oxidation. 相似文献
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以海水冲厕污水作为培养液培养小球藻(Chlorella vulgaris),研究了小球藻的生长及其对海水冲厕污水中氮、磷和有机物的净化作用,并对小球藻细胞总脂含量和脂肪酸组成进行了分析。结果表明:小球藻在以海水冲厕污水作为培养液时,其生长速率和生物量与在BG11培养液中生长时相比明显较低;小球藻能够有效吸收海水冲厕污水中的氮、磷,12d时对氨氮和总磷的去除率分别达到87.9%和98.2%;采用海水冲厕污水培养出的小球藻细胞总脂含量达到33.03%,其脂肪酸组成与采用BG11培养的相比略有变化,总体以C16和C18为主,符合作为生物柴油生产原料的要求。 相似文献
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酶法制备生物柴油工艺引起了越来越多的关注。本文以脂肪酶回收前后脂肪酸甲酯得率之比作为检测指标,采用响应面法对自行制备的固定化洋葱伯克霍尔德菌脂肪酶的回收工艺参数进行了优化,并利用软件SAS 9.0对实验数据进行分析。确定的最佳回收条件:回收溶剂用量20.4 mL,回收温度40.2℃,回收时间20 m in。此条件下,验证试验脂肪酶回收率最大可达98.26%,与回归模型预测最优条件下脂肪酶回收率99.59%非常接近,且使用30次后,其回收效率依然接近100%。R2=96.63%显示该回归模型在分析脂肪酶回收率方面具有极高的准确性和可信度。 相似文献
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《分离科学与技术》2012,47(5):1228-1239
Abstract Water in hydrothermal condition has been used for extraction of nutraceutical compounds from Chlorella vulgaris. Hydrothermal extraction was carried out in a semi-batch and a batch extractor at various temperatures (120–200°C), pressures (2–10 MPa), and extraction times (30–300 min) to extract antioxidant and antibacterial compounds. The effect of extraction condition on the yield of extract was investigated. The antioxidant and antibacterial activity of extracts obtained by hydrothermal extraction were examined. The increasing extraction temperature resulted in higher antioxidant activity, but lower antimicrobial activity. As comparison with hot water extraction, the antioxidant activity of extract obtained by hydrothermal extraction was higher than that obtained by hot water extraction, but the antibacterial activity of the extract obtained by hydrothermal extraction was lower. 相似文献
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Kiwa Kitada Siti Machmudah Mitsuru Sasaki Motonobu Goto Yuya Nakashima Shoichiro Kumamoto Takashi Hasegawa 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(5):657-661
BACKGROUND: Chlorella vulgaris is a green microalgae that contains various pigment components of carotenoids and chlorophylls. Supercritical CO2 is widely used for extraction of pharmaceutical compounds because it is non‐oxic and easily separated from extracted material by simply depressurizing. In this work, pharmaceutical compounds from Chlorella vulgaris have been extracted using supercritical CO2 with or without entrainer at various extraction conditions. RESULTS: Based on high performance liquid chromatography (HPLC) analysis, the extracts contained pigment components, such as lutein, β‐carotene, chlorophyll a and b. Higher extraction pressure and temperature promoted higher lutein extraction by supercritical CO2. The optimum pressure and temperature for extraction were obtained as 50 MPa and 80 °C. Ethanol as an entrainer was more effective than acetone for the extraction of pigment components. Pigment components in the extract obtained by supercritical CO2 with and without entrainer were compared with the extract obtained by a conventional extraction method. CONCLUSION: Supercritical CO2 has been successfully applied for the extraction of pigment components from Chlorella vulgaris. Supercritical CO2 enabled high selectivity for lutein extraction; however, the lutein yield was lower than that obtained by extraction using supercritical CO2 with ethanol and soxhlet. Copyright © 2008 Society of Chemical Industry 相似文献
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利用自行设计的阴极管状光生物反应器式微生物燃料电池(MFC)作为实验模型,考察了阴极室投加小球藻后不同光暗周期下电池的产电、阴极溶氧及阴极藻的生长情况. 结果表明,阴极投加小球藻后,电池产电性能明显提高,光暗间歇组最大功率密度为24.4 mW/m2,持续光照组最大功率密度为27.5 mW/m2. 阴极溶氧及电化学分析证实溶氧是影响电压变化的主要因素,持续光照组溶氧较稳定,但比光暗间歇组光照阶段溶氧水平低;MFC阴极室培养小球藻不会对其造成毒害,光暗间歇时小球藻生长较好. 运行小球藻生物阴极型MFC采用光暗间歇培养较好,并可适当延长光照时间. 相似文献
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Large‐scale biomass production and sewage refining for use in landscaping by employing Chlorella vulgaris were investigated. The effects of the concentrations of carbon, nitrogen, and phosphorus as nutrients in the process were optimized by central composite design. In general, the results revealed that higher amounts of biomass can be obtained by varying the feed concentration; both the N and P concentrations have an effective role in improving the biomass dry weight. The amount of lipid productivity varied from 12 % to 55 %, and one of the photobioreactors tested showed the best conditions for lipid productivity. Also, this process can decrease the greenhouse gas emissions in wastewater treatment. 相似文献
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Ilgi Karapinar Kapdan Sebnem Aslan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(7):998-1005
BACKGROUND: The aim of this study was to evaluate the ammonium nitrogen removal performance of algae culture Chlorella vulgaris in a novel immobilized photobioreactor system under different operating conditions and to determine the biokinetic coefficients using the Stover–Kincannon model. RESULTS: The photobioreactor was continuously operated at different initial ammonium nitrogen concentrations (NH4‐N0 = 10–48 mg L−1), hydraulic retention times (HRT = 1.7–5.5 days) and nitrogen/phosphorus ratios (N/P = 4/1–13/1). Effluent NH4‐N concentrations varied between 2.1 ± 0.5 mg L−1 and 26 ± 1.2 mg L−1 with increasing initial NH4‐N concentrations from 10 ± 0.6 mg L−1 to 48 ± 1.8 mg L−1 at θH = 2.7 days. The maximum removal efficiency was obtained as 79 ± 4.5% at 10 mg L−1 NH4‐N concentration. Operating the system for longer HRT improved the effluent quality, and the percentage removal increased from 35 ± 2.4% to 93 ± 0.2% for 20 mg L−1 initial NH4‐N concentration. The N/P ratio had a substantial effect on removal and the optimum ratio was determined as N/P = 8/1. Saturation value constant, and maximum substrate utilization rate constant of the Stover–Kincannon model for ammonium nitrogen removal by C. vulgaris were determined as KB = 10.3 mg L−1 d−1, Umax = 13.0 mg L−1 day−1, respectively. CONCLUSION: Results indicated that the algae‐immobilized photobioreactor system had an effective nitrogen removal capacity when the operating conditions were optimized. The optimal conditions for the immobilized photobioreactor system used in this study can be summarized as HRT = 5.5 days, N/P = 8 and NH4‐N0 = 20 mg L−1 initial nitrogen concentration to obtain removal efficiency greater than 90%. Copyright © 2008 Society of Chemical Industry 相似文献
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The performance of a modified bioreactor inside a light enclosure for carbon dioxide biofixation by Chlorella vulgaris was investigated. The influence of different light intensities on the CO2 biofixation and biomass production rates was evaluated. The results showed that the photon flux available to the microalgal cultures can be a key issue in optimizing the microalgae photobioreactor performance, particularly at high cell concentrations. Although the optimal pH values for C. vulgaris are in the range of 6–8, cell growth can take place even at pH 4 and 10. Batch microalgae cultivation in the photobioreactor was used to investigate the effect of different light intensities. The maximum biomass concentration of 1.83 g L?1 was obtained at a light intensity of 100 μmol m?2s?1 and under aeration with 2 L min?1 of 2 % CO2‐enriched air. 相似文献
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The symbiotic relationships between Chlorella vulgaris and Bacillus bacteria in fracturing wastewater treatment were investigated under different conditions, including varying dilution ratios of fracturing wastewater (2-4), dosages of bacteria (20 mg/L-80 mg/L), and pH (6.5-8.5). The effects of process variables on the response of algal density were optimized and investigated via the Box-Behnken response surface design. The individual and interactive effects of process variables on the response were studied by a second-order polynomial model and three-dimensional response surface plots. The optimal treatment conditions were a dilution ratio of 2, bacteria dose of 72.13 mg/L, and pH of 6.5, and the maximum biomass concentration of Chlorella vulgaris was 2.23 g/L. Moreover, Bacillus bacteria can increase the activity of superoxide dismutase (SOD) and acetyl-CoA carboxylase (ACCase) of Chlorella vulgaris. Compared to the free Chlorella vulgaris, the co-cultivation of Chlorella and Bacillus bacteria can improve the algal growth and degradation of organic pollutants. 相似文献