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971.
Potentials of phototrophic bacteria in treating pharmaceutical wastewater   总被引:7,自引:6,他引:1  
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.
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.
济阳坳陷上第三系馆陶组是胜利油田的主要产油气层段。近些年来,浅层气的勘探日益受到人们的重视。但是,很少发现较大型的浅层气藏,这与该层位的储量相比是不相配的,造成这种现象的原因何在?本文则想通过对浅层储集层及盖层条件的研究,分析两者对浅层天然气分布的影响,预测有利的浅层气分布地区。  相似文献   
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.
根据陕西省2001和2003年两期的GPS测站的观测资料,给出了鄂尔多斯块体南缘现今地壳水平应变场。结果表明,最大剪应变和面应变的高值区主要集中在该区中部和东部,尤其是在中部的咸阳、泾阳附近,东部的合阳、大荔、渭南一带以及西北部的陇县附近,主要受面收缩影响,分别形成了几个较为显著的应挛高值区。等值线较密集并且应变梯度也较大,这些区域具备一定的孕震条件,有可能是未来发震地点。  相似文献   
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.
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   
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