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191.
叶宏  孙倩云 《四川环境》1997,16(1):34-36
酿造废水属于高浓度有机废水,要将其处理达到排放标准,必须经过多种处理工艺的组合才能办到。通过物化处理、生化处理的实验室研究,我们得出了资源化和净化相结合的优化工艺组合,使酿酒废水的排放达到规定的排放标准,且运行费用和收益基本持平,解决了环保工程与经济效益间的矛盾。  相似文献   
192.
ABSTRACT: Twenty, 0.2 hectare ponds were utilized for a four-year evaluation of three aquatic vegetation control techniques: a combination of inorganic fertilization and mechanical harvesting, aquatic herbicides, and grass carp (Ctenopharyngodon idella). Ponds used for herbicide and grass carp treatments were managed at three levels of aquatic vegetation (none, 40 and 70 percent plant occupation). Submersed vegetation was not controlled with inorganic fertilization. Vegetation levels were maintained for less than 30 days after mechanicai harvesting. Submersed macrophytes were not completely eliminated with herbicides, but the herbicide treatments utilized were effective at maintaining aquatic vegetation above 30 percent pond volume occupation. Grass carp consumed all species of submersed vegetation at the stocking densities used in this study; therefore, planned levels of submersed macrophytes were not maintained. Grass carp did not consume all floating leaf vegetation, but after four years some grass carp ponds did have lower densities of floating leaf plants. Fertilization costs were $608/hectare/year, and mechanical harvesting costs were $1979/hectare/year, resulting in a total aquatic vegetation treatment cost of $2587/hectare/ year. Herbicide costs for the different treatment levels ranged from $417/hectare/year to $1339/hectare/year over the four-year period. Grass carp were the most economical vegetation control measure tested, with costs ranging from $159/hectare/year to $248/hectare/year for the four-year study.  相似文献   
193.
棉浆粕蒸煮黑液处理工程实践   总被引:2,自引:0,他引:2  
棉浆行业碱法蒸煮黑液是当前废水治理中的难题之一。本文介绍采用酸析气浮 +A O法 +混凝工艺处理棉浆黑液的工程实例。工程运行结果表明 :该工艺对CODCr和色度的去除率可达 98%以上 ,出水水质达到排放标准 ,并且处理效果稳定  相似文献   
194.
Blending soy protein with polyesters using a polyvinyllactam as a compatibilizer successfully made soy protein-based plastics. The polyesters used to produce blends included polycaprolactone (PCL) and Biomax (a commercial biodegradable polyester). The blends were processed by compounding extrusion and injection molding. Blends containing soy protein/Biomax-poly(vinyl alcohol) had tensile strengths ranging from 16–22 MPa, with samples containing larger percentages of the synthetic polymer exhibiting greater strengths. Blends made from soy protein, Biomax, and PCL had tensile strengths ranging from 27–33 MPa. All the blends had high Young's moduli but demonstrated brittle characteristics as evident from their low elongations at break, ranging from 1.8–3.1%. Plastics made from soy protein/polyester blends exhibited low water absorption and had good stability under ambient conditions relative to the plastics made from soy protein alone. Blends made from soy protein flour produced plastics with the lowest water absorption.  相似文献   
195.
Effects of Storage Time on Properties of Soybean Protein-Based Plastics   总被引:1,自引:0,他引:1  
Soybean protein has been considered as a potential biodegradable polymer in the manufacture of plastics. The purpose of this investigation was to characterize the effect of storage time on thermal and mechanical properties of soybean protein isolate (SPI) plastics. SPI was separated from defatted soy flour, modified with 1M or 2M urea, or plasticized with glycerol, and compression molded into plastics. Plastic made from SPI alone was used as a control. For all SPI plastics, glass transition temperatures and dynamic storage modulus increased and loss tangent decreased during storage. Excess enthalpy of relaxation of all SPI plastics had an exponential relationship with storage time, indicating a fast aging rate at the beginning of storage. All SPI plastics tended to be stiff and brittle during storage. The plastics with glycerol had the slowest aging rate and were fairly stable after 60 days, with about 8.8 MPa tensile strength and 168% strain at break. Plastics with the 2M urea-modification SPI also had a slow aging rate and became relative stable after 60 days, with about 10 MPa tensile strength and 72% elongation.  相似文献   
196.
表面活性剂及酸处理对污泥脱水性能影响的研究   总被引:12,自引:0,他引:12  
研究表面活性剂和酸处理对污泥脱水性能的影响,并探讨其作用机理。对采用最优加药量的各种加药方案进行了从污泥性质到脱水行为的一系列横向比较。污泥性质的比较依据为絮体颗粒的宏观(目测)和微观(光学和电子显微镜)变化以及在结合水含量(DSC法测)方面的变化。脱水行为的比较依据为过滤脱水速率(比阻)、离心脱水速率(1800rpm-2min离心后的泥饼含固率)、脱水程度(4800rpm~45min离心后的泥饼含固率)及脱水清液的性质(目测及测定SS、COD、TP)。实验结果表明:除了表面活性剂与Fe^3 和CaO联用外,投加表面活性剂或酸处理对提高污泥脱水速率的意义不大,但却能有效提高污泥的机械脱水程度。表面活性剂的作用机理是:分散作用使污泥絮体结构分散解体,释放出原絮体内部的结合水;增溶作用可溶解有高度水合作用的ECP。酸处理的作用机理是:H^ 与污泥的结合,改变了污泥的表面电荷特性,促进了污泥絮体间进一步的絮凝;使ECP水解,降低了絮体对水的亲和力。  相似文献   
197.
目的 探究一种可替代AgCdO的高性能且环境友好的新型电接触材料,以提升航天继电器的可靠性。方法 在一定条件下以合金内氧化法制备AgCuONiO电接触材料,并与商用AgCdO电接触材料进行对比,利用电寿命模拟试验分析2款材料的电寿命循环服役性能,分析其失效机理。结果 AgCuONiO材料的总质量损失为0.000 88 g,平均燃弧时间、燃弧能量、熔焊力、回跳次数、回跳时间、回跳能量分别为4 222μs、694 mJ、0.049 N、1.799次、592.999μs、63.892 mJ,均大于商用AgCdO电接触材料,但其接触电阻低,且稳定,失效模式为无法分断电弧,而商用AgCdO电接触材料为粘连失效。AgCuONiO电接触材料的电寿命服役周期为44073次,是AgCdO电接触材料的3倍左右,因此可以显著提高航天继电器的可靠性。结论AgCuONiO电接触材料的一些电寿命服役性能虽然不如商用AgCdO电接触材料,但其电寿命服役周期明显强于商用Ag Cd O电接触材料,可作为替代AgCdO的较佳候选材料之一,应用于服役寿命要求更长的航天继电器。  相似文献   
198.
为解决那些由于早期桥梁的设计标准低或服役时间过长,导致破损、承载力不足以及老化严重的问题,对部分已建桥梁提出改扩建计划。对桥梁改扩建工程,在满足当前设计要求的基础上合理选择钢筋与混凝土等级,可以有效节约成本,体现环保理念。通过对两组共8根不同钢筋与混凝土等级组合下的PPC梁分别进行静力试验和疲劳试验研究,分析不同组合形式下试验梁的力学性能,并结合其工程造价进行全面的研究。结果表明,提高混凝土等级能有效提高试验梁的疲劳性能,并可节约成本,为改扩建桥梁工程中钢筋混凝土等级的选择提供参考依据。  相似文献   
199.
Insists of polymer matrix composite is prepared by using natural fiber facilitates high tensile, flexural, and impact toughness properties. The natural fiber utilization in the polymer matrix can overcome the synthetic fiber demerits of poor compatibility, high moisture absorption, and high cost. The present research investigates developing a low-cost, environmentally eco-friendly epoxy hybrid composite using different volume percentages of chopped natural waste banana (0Vol%, 5Vol%, 10Vol%, and 15Vol%) and sisal fiber (0Vol%, 15Vol%, 10Vol%, and 5Vol%) through hand mould hot compression technique. The presence of natural waste banana and sisal fiber on tensile strength, flexural strength, and thermal adsorption properties of the epoxy hybrid composite are evaluated by ASTM test standards. The ASTM standard measured test results of epoxy hybrid composite with and without natural waste banana and sisal fiber were compared and sample three was identified by good tensile strength, flexural strength, and better thermal adsorption properties compared to all others. The sample three epoxy hybrid sample is recommended for automotive roof application.  相似文献   
200.
地铁车厢机械排烟和细水雾耦合灭火效果研究   总被引:2,自引:1,他引:1  
采用火灾动力学软件FDS(FireDynamicSimulator),以封闭单节地铁列车车厢为研究对象,模拟分析不同喷雾速度、排烟量以及排烟启动时刻条件下,车厢内火灾热释放速率、烟气层高度、烟气层温度的变化规律,对细水雾和机械排烟耦合作用下地铁列车车厢火灾灭火效果展升研究。结果表明,喷雾初速度较小时,细水雾动作之后启动排烟系统的灭火效果更好;喷雾初速度较大时,细水雾动作之前启动排烟系统的灭火效果更好;同样的喷雾初速度条件下,增大排烟量町以提高烟气层高度和降低烟气层温度,排烟量过大可能造成火焰区的扰动,降低细水雾的火火效果。  相似文献   
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