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971.
E. I. Madukasi X. Dai C. He J. Zhou 《International Journal of Environmental Science and Technology》2010,7(1):165-174
A suspended growth photobioreactor was utilized to treat pharmaceutical wastewater by a wild strain purple non-sulfur photosynthetic bacterium isolated from the soil. The strain was named Z08 and identified as Rhodobacter-sphaeroides by 16SrDN. The photobioreactor was illuminated externally with two (40 W) fluorescent compact light sources on both sides. Its operation pH and temperature were between 6.8–7.0 and 20–30 °C, respectively. Optimum growth of the isolate was obtained after enrichment of the pharmaceutical wastewater with 0.5 % ammonium sulfate and 0.1 % yeast extract under microaerobic optimum light (6000 lx) condition at 5d retention. Using these optimum conditions, the maximum dry cell weight and chemical oxygen demand percentage removal were 880 mg/L and 80 %. Chemical analysis of the culture after treatment of the enriched and non-enriched wastewater showed the crude protein content of the biomass to be 54.6 % and 38.0 %, respectively. This study proved that photosynthetic bacteria could transform complex wastewater that contains recalcitrant organic compounds with a resultant recovery of useful products. 相似文献
972.
Yan-Wei Xie Jing-Bo Wang George Hobbs Jane Kaczmarek Di Li Jie Zhang Shi Dai Andrew Cameron Lei Zhang Chen-Chen Miao Mao Yuan Shen Wang Song-Bo Zhang Heng Xu Ren-Xin Xu 《天文和天体物理学研究(英文版)》2019,(7)
Flux densities are fundamental observational parameters that describe a pulsar. In the current pulsar catalogue, 27% of the listed radio pulsars have no flux density measurement in the 20 cm observing band. Here, we present the first such measurements for 32 pulsars observed employing the Parkes radio telescope. We have used both archival and new observations to make these measurements. Various schemes exist for measuring flux densities and we show how the measured flux densities vary between these methods and how the presence of radio-frequency interference will bias the flux density measurements. 相似文献
973.
974.
????OKADA??????????????????????????????????????????????α???????????????????????α??????????????????????????,??????????,???????α?????-109.7 cm??????????????????α????19.2 cm??????????????????????????????????????α?????-51.4 cm????????????,????α?????98.5 cm???????????????????????????????????????α?????-66.5 cm?????????????????????α????25.8 cm????????????α?????????????????????????????????????α???????????????????????????????????????????? 相似文献
975.
976.
提出一种基于机器学习的食双星光变曲线自动分类算法。首先对数据进行预处理,将食双星光变曲线数据归一化,并通过滤波/插值降低噪声;其次使用快速傅里叶变换提取频率信号作为特征向量;最后利用特征向量训练支持向量机获得自动分类模型。使用Python实现算法并抓取CALEB和GCVS数据验证,分析特征向量、支持向量机核函数与惩罚系数对分类正确率的影响,优化后所得分类模型正确率达到92.8%(训练集)和89.0%(测试集),最后使用所得分类模型对第3方数据进行分类,正确率为88.8%,结果证明提出的分类算法的有效性。 相似文献
977.
???????????????????????????????????У???????????????????????и????????????????????????μ???????????顣????????????÷????????????????????????????????????????????????????????????Ч??????? 相似文献
978.
Fe^2+ acted as an accessorial factor for many cellular enzymatic reactions is very important for seaweed growth and development, but the Fe^2+ requirement in nori had not been seen. Porphyra yezoensis cells were separated enzymatically and cultured in a series of sterilized seawater media containing various concentrations of Fe^2+. The growth development and cell were investigated in this work. Through this experiment, two biologically-meant concentration scales were found, one is low concentrations, 12.1-102.1μg/L, 10-100 times than that in seawater, favoring the development of isolated cells of Porphyra and the other was high concentrations, more than 10mg/L inhibiting the cell growth, leading to the deformity and shrinkage of the cells. At the concentration of 50 mg/L, the cells stopped growing and died eventually. 相似文献
979.
Analysis on the key findings related to emission trends and drivers from the IPCC AR6 report北大核心CSCD
Emission Trends and Drivers chapter, an important basis for international climate negotiations, is one of the core contents of each assessment report. The trends and driving factors of greenhouse gas emissions from 1990 to 2019 are discussed in this chapter in the Sixth Assessment Report (AR6) released in April 2022. Compared with the content in the Fifth Assessment Report (AR5), in terms of historical emission trends, AR6 focuses on the changes from 2010 to 2019, highlights the importance of the 1.5°C temperature control target, pays more attention to carbon dioxide (CO2) emissions and non-carbon dioxide greenhouse gas emissions related to land use change, and further emphasizes the carbon emission trend and its regional evolution trend from the perspective of production and consumption. Besides, the short-term impact of COVID-19 on global carbon emissions is explored. In terms of driving factors, besides analyzing the global and regional economic driving factors, the economic driving factors and differences in energy, industry, construction, transportation, agriculture, forestry and other land use (AFOLU) sectors are also studied, which systematically reflects the similarities and differences of driving factors at the global, regional and departmental levels. The results affirm the positive impact of existing climate policies on climate mitigation highlight the benefits of technological change and innovation on climate mitigation, and identify the adverse impact of carbon locking of fossil energy infrastructure. Finally, based on the full analysis of the key conclusions in AR6, some suggestions on China's low-carbon development are given. © 2022 Chinese Journal of Digestive Endoscopy All rights reserved. 相似文献
980.
???????????????????????????????????????????????????????????????????????Ч????????????????????λ??????????????????????вο????????????в????????????顣????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? 相似文献