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171.
本文建立了崂山水库上游区生态环境需水量的计算方法,并计算了该区域的生态环境需水量.结果表明崂山水库上游区生态环境需水量为3089.78×104m3,其中植被生态环境需水量为2792.7×104m3,河流生态环境需水量为291.95×104m3,水库生态环境需水量为5.13×104m3.崂山水库上游区生产生活用水总量为63.67×104m3,多年平均水资源总量为4032.7×104m3,说明从全年来看该区域生态环境需水能够得到基本满足.但径流量年内分配极不均匀,大部分集中于丰水期,枯水期的生态环境需水可能无法保障. 相似文献
172.
The influence of benzene concentration on the specific growth rate (mu), CO(2) and metabolite production, and cellular energetic content (i.e., ATP content), during benzene biodegradation by Pseudomonas putida F1 was investigated. Within the concentration range tested (5-130mg benzene l(-1)) the mu, the specific CO(2) production, and the ATP content remained constant at 0.42-0.48h(-1), 1.86+/-0.21g CO(2) g(-1) biomass, and 5.3+/-0.4x10(-6)mol ATP g(-1) biomass, respectively. Catechol accumulated during process start-up at all tested concentrations. Catechol specific production increased with increasing benzene inlet concentrations. This confirms that the transformation of this intermediate was the limiting step during benzene degradation. It was shown that catechol inhibited both the conversion of benzene to catechol and its further transformation. In addition, catechol concentrations higher than 10mgl(-1) significantly decreased both benzene and catechol associated respiration, confirming the highly inhibitory effect of this intermediate. This inhibitory threshold concentration was approximately two orders of magnitude lower than the concentrations present in the culture medium during process start-up, suggesting that cellular activity was always far below its maximum. Thus, due to its toxic and inhibitory nature and its tendency to accumulate at high benzene loading, catechol must be carefully monitored during process operation. 相似文献
173.
针对油气事故后应急资源需求预测困难的问题,在对油气事故特性及应急资源需求类型分析的基础上,构建了基于案例推理(CBR)的油气事故应急资源需求预测模型,并使用Visual Basic.NET及SQL Server数据库开发了油气事故应急资源需求预测支持决策系统。将该系统应用于实际油气事故案例进行验证,结果表明系统中应急资源需求预测模型科学可靠,系统对油气事故应急资源需求预测结果与其实际用量基本吻合。该系统可为油气事故后快速有效开展应急救援活动提供相应的理论依据。 相似文献
174.
175.
箱体零件是矿井机械中重要的基础零件。它的加工质量直接关系矿井设备的寿命、机器的性能和安全性。针对煤矿井下煤尘和瓦斯存在的环境特性、煤矿井用箱体防爆面加工的特殊要求,采用控制理论的信息流图,对工艺过程中传统方块图进行简化,使繁杂的方块图解采用信息流图表示工艺过程的工序(变量)之间关系。进而讨论箱体零件加工工艺过程误差转换模型、形状精度特征、传递图、描述方程、误差转换结构图;提出防爆面磨削工艺系统的数学模型;求解出振动特性、幅值和相位,得出了形状误差与工艺参数的关系曲线。实践证明,合理选择磨削参数,能够保证煤矿井下工作机械具有高的防爆性能,达到矿井安全生产的技术要求。 相似文献
176.
穆海云 《中国安防产品信息》2006,(1):105-110
德国特警部队主要分为5支,他们是德国陆军特种部队(KSK--Kommando Spezial Kraefte)、德国国境警备部队9队(GSG-9--Bundesgrenzschutz Grenzschutzgruppe-9)、德国警察特别作战部队(SEK-Spezialeinsatzkommandos der deutschen Polizei)、德国海关中心支援部队(ZUZ)、德国水上战斗部队(实战部队3402). 相似文献
177.
178.
Ao Ran Ma Liping Guo Zhiying Yang Jing Mu Liusen Yang Jie Wei Yi 《Environmental science and pollution research international》2021,28(6):6929-6940
Environmental Science and Pollution Research - Perovskite is an efficient and emerging catalyst for NO oxidation. In this study, BaMnO3 and BaCoO3 perovskite catalysts were synthesized by the... 相似文献
179.
Microalgae as a main feedstock has attracted much attention in recent years but is still not economically feasible due to high algal culture cost. The objective of this study was to develop a comprehensive eco-friendly technology for cultivating microalgae Platymonas subcordiformis using aquaculture wastewater as growth medium for biomass and biofuel production. Platymonas subcordiformis was grown in pretreated flounder aquaculture wastewaters taken from different stages. Each of wastewater contained different levels of nutrients. The biomass yield of microalgae and associated nitrogen and phosphorous removal were investigated. The results showed that algal cell density increased 8.9 times than the initial level. Platymonas subcordiformis removed nitrogen and phosphorus from wastewater with an average removal efficiency of 87%-95% for nitrogen and 98%-99% for phosphorus. It was feasible to couple the removal of nitrogen and phosphorus from wastewater to algal biomass and biofuel production. However, further studies are required to make this technologies economically viable for algae biofuel production. 相似文献
180.
Nine compounds were isolated from the spikes of Prunella vulgaris by various kinds of chromatography. Their structures were established on the basis of spectral analysis as polygalacerebroside (1), ursolic acid (2), β-amyrin (3), quercetin (4), quercetin-3-O-β-D-galactoside (5), β-spinasterol (6), stigmasterol (7), β-sitosterol (8), daucosterol (9). Compound 1 was isolated from this genus for the first time. Phytochemical investigation on the spikes of P. vulgaris provided chemical constituents diversity, which were performed to facilitate further development and utilization of P. vulgaris pharmaceutical resource. 相似文献