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391.
392.
Masahiro?ShimadaEmail author Takahiko?Iida Kensuke?Kawarada Yoshifumi?Chiba Toshihiro?Mamoto Takayuki?Okayama 《Journal of Material Cycles and Waste Management》2004,6(2):111-118
We have previously manufactured activated carbon using waste paper board, which was prepared by adding 8% phenol resin adhesive to torn waste newspaper and hot-pressing. In this study, the pretreatment process of the raw material was simplified; the waste paper was extruded to form granules. The activated carbon was manufactured by the carbon dioxide activation method using the granules as the raw material. The properties of the activated carbon were evaluated based on the pore structure, the iodine adsorption number, and the adsorption of toluene vapor in a sealed chamber. The activated carbon, which was manufactured at an activation temperature of 1100°C and a treatment time of 60min, exhibited a specific surface area of 1241m2/g and an iodine adsorption number of 1120mg/g. These results were similar to those obtained for two commercially available activated carbons. The extent of toluene vapor adsorption by this activated carbon was similar to that observed for the two commercial activated carbons over a period of 130min. 相似文献
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Bhanu Pratap Ram M.V. Nitin 《Journal of Loss Prevention in the Process Industries》2005,18(4-6):283-292
An approach, based purely on steady-state analyses, for synthesizing effective control structures for reactive distillation (RD) columns is presented. The main idea is to analyze the steady-state relationships between the manipulated (input) variables and the potential controlled (output) variables to identify input–output (IO) pairings that are sensitive and avoid steady-state multiplicities providing a large range of nearly linear operating region around the base case design. Traditional SISO control loops are then implemented using these IO pairings to obtain control structures that maintain the column near the design product purity and conversion for the anticipated primary disturbances. The Niederlinski Index is used to eliminate dynamically unstable pairings in control structures with multiple loops. The approach is demonstrated on an example MTBE RD column. The impact of steady-state multiplicities on control structure design is highlighted. 相似文献
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Heart rot is a common soil-borne disease in the pineapple industry, but the situation can be alleviated by the application of bio-fertilizers with beneficial microbiomes. Clarifying the controlling mechanism of bio-organic fertilizer on the high incidence of heart rot is critical in monocultural pineapple cropping patterns. In our study, the soil of continuous cropping pineapple orchards was collected. Three types of carriers (rapeseed cake, peat soil, and coconut bran), biocontrol strains (Bacillus subtilis HL2 and Streptomyces strain HL3), and organic fertilizer (YJ) were composted into different bio-fertilizers (KC, KN, KY, LC, LN, and LY), which were used in pot experiments. The controlling effect of the bio-fertilizer was determined based on the response of pineapple heart rot and bacterial communities to different fertilizing methods. Our results revealed that the incidence of heart rot in bio-fertilizer KC was the lowest, which decreased by 20% and 13.3%, respectively, compared to HF (chemical fertilizer, 16-16-16) and YJ (organic fertilizer). The richness and diversity of soil bacterial communities in all biofertilized treatments (KC, KN, KY, LC, LN, and LY) were significantly higher than those in HF. However, the α-diversity indices of the bio-fertilizers (KC, KN, and KY) were higher than those of LC, LN, and LY, and the bacterial community composition was significantly different. The bacteria GP4, GP6, Bacillus, and Azohydromonas were enriched in KC, KN, and KY, while the relative abundance of Streptomyces increased significantly in LC, LN, and LY. Furthermore, Spearman correlation analysis showed that the relative abundance of these bacterial groups was significantly negatively correlated with the incidence of pineapple heart rot. In summary, the application of bio-organic fertilizers can decrease the incidence of pineapple heart rot by altering the soil bacterial community structure and stimulating beneficial soil microorganisms, which is important for reconstructing the ecological balance in continuous pineapple orchards. © 2022 Authors. All rights reserved. 相似文献
397.
巢湖流域河流鱼类群落的时空分布 总被引:2,自引:0,他引:2
基于2013年4月和10月对巢湖流域66个河道样点的调查数据,初步研究了巢湖流域河流鱼类群落的时空变化特征。主要研究结果显示,鱼类多样性无显著性的水系间、生态分区间的变化,但随季节和河流级别显著变化:10月份的个体数显著高于4月份,2级河流的物种数和个体数均显著大于1级、3级和4级河流。鱼类群落结构的季节动态显著,随生态分区显著变化,但不受水系、河流级别的显著影响。在二级生态分区水平上,仅西南森林生态亚区的鱼类群落结构与其他5个生态亚区的显著差异;宽鳍鱲、吻虾虎鱼等在西南森林生态亚区具有更高多度,而鲫、鰐、鲤等物种在其他生态亚区多度更高。 相似文献
398.
针对粉煤灰排放产生二次污染问题,经过分析比较,选用了科学的加湿排放工作原理,设计了用于粉煤灰排放的新型灰料加湿卸灰机。 相似文献
399.
宁波东钱湖大型底栖动物群落动态及水质生物学评价 总被引:1,自引:0,他引:1
2009年4月—2010年1月,对东钱湖大型底栖动物群落结构及空间分布格局进行了季度调查,并对其环境状况进行生物学评价.共记录底栖动物3门4纲28属30种,其中寡毛类5种、水生昆虫18种、软体动物7种.底栖动物密度、生物量和群落周年次级生产量分别为1 233 m-2、8.0 g/m2(以湿质量计)和35.3 g/(m2.a)(P/B系数法估算),单因素方差分析显示,秋、冬季显著高于春、夏季.东钱湖底栖动物优势种为红裸须摇蚊、长跗摇蚊、菱跗摇蚊和霍甫水丝蚓,红裸须摇蚊为冬季单一优势种.依据底栖动物密度的多维序列分析,可将东钱湖分为4个湖区.基于GIS平台,运用克里格插值法,构建动物参数及BI(Hilsenhoff生物指数)的空间分布格局,显示东钱湖底栖动物群落具有较强的空间异质性:摇蚊幼虫多分布在谷子湖及中部湖区,而软体动物主要聚集在中部偏西南及北部湖区.BI评价结果表明,东钱湖的整体水质为中度污染(BI为7.58),其在时空上有较大差异.其中,2009年4、7、9月为轻度污染(BI为6.66~7.33),2009年11月—2010年1月为中度污染(BI为8.32~8.39);在空间尺度上,中部及北湖偏东部湖区污染较轻,其次为谷子湖及五里塘湖区,南湖偏南部湖区污染较重. 相似文献
400.
多目标规划在产业结构优化中的应用——以秦皇岛市为例 总被引:1,自引:0,他引:1
秦皇岛是缺水城市,水资源短缺已成为制约经济发展的瓶颈。合理利用水资源对经济发展意义重大。本文采用多目标规划方法,构建了秦皇岛市水资源约束条件下的产业结构优化模型,提出了秦皇岛市产业结构优化方案。 相似文献