等离子球磨机的研制及其振动平台试验

目的实现球磨室在常压下的大面积介质阻挡放电等离子体,开发出商用等离子球磨机。方法通过在不同弹簧和平台质量条件下,利用振动传感器测试平台的振幅(峰峰值)和加速度(有效值)数值,对比确定最优配置和机械振动参数。结果当振动平台振幅接近球磨室内径时,获得高振幅和高加速度的磨球,显著缩短了气体放电间距,实现了球磨室在常压下的大面积介质阻挡放电等离子体。所设计的单筒等离子振动球磨机,其振动平台可选用φ7 mm、φ8 mm两组弹簧,根据平台质量的不同,选择不同类型的激振块组合,可以在30 Hz转速以上实现平台振幅峰峰值达到或者接近球磨罐内径值,同时拥有10g以上的加速度有效值。结论本试验综合机械振动学、高压绝缘放电和材料加工技术,所研制的等离子体球磨机实现了机械能和等离子体能在球磨过程中的协同作用,显著提高了粉末活性,降低了化合物合成反应激活能,从而显著提高了所制备材料的性能。     

侧联式球磨机的噪声控制

介绍了侧联式球磨机噪声产生原理及其噪声控制方法，选择了制作局部式隔声罩的噪声控制设计和装置结构。在中国铝业中州分公司热电厂球磨机上应用，取得了很好的隔声效果。     

Assessing the aerodynamic effects of tail elongations in the house martin (Delichon urbica): implications for the initial selection pressures in hirundines

Of the three species of hirundine that breed sympatrically across the U.K., one, the barn swallow, has outer tail feathers elongated into streamers, whereas the other two species, the house martin and the sand martin, do not. The tail streamer of the barn swallow is regarded as a classic example of a sexually selected trait. Recent evidence, however, has suggested that streamers may have evolved largely through natural selection for enhanced flight performance and increased maneuverability. We tested the hypotheses that small streamers (1) increase performance in turning flight, but (2) decrease performance in flight variables related to velocity. We manipulated the lengths of house martin outer tail feathers and measured changes in their free-flight performance, using stereo-video to reconstruct the birds" three-dimensional flight paths. Five flight variables were found to best describe individual variation in flight performance. Of these five, the three variables determining maneuverability predicted that flight performance would be optimized by a 6- to 10-mm increase in the length of the outer tail feathers. In contrast, for mean velocity and mean acceleration, extension of the outer tail feathers appears to have a detrimental effect on flight performance. We suggest that the initial selection pressure for streamers in ancestral short-tailed "barn swallows" was via natural selection for increased maneuverability. In addition, we propose that the benefits of increased maneuverability have differed between hirundines in the past, such that the cost of increasing the length of the outer tail feather has, to date, outweighed the benefits of doing so in streamerless hirundines. Received: 14 February 2000 / Revised: 2 July 2000 / Accepted 18 July 2000     

Toxicity attenuation of olive mill wastewater in soil slurries

Olive mill wastewaters are toxic for plants and microbes due to their high polyphenol content. We studied the effect of agricultural soil as a natural catalyst to promote polyphenol oxidation and polymerization, and in turn detoxify olive mill wastewaters. We show that model polyphenols are fully converted in soil slurries. Their products show no toxicity to the growth of a typical soil bacterium, Bacillus cereus, and reduced phytotoxicity in germination tests with English cress seeds. Those findings are promising for the sustainable treatment of olive wastewater in aerated soil slurries.     

造纸废水高效生化处理情况

阐述了某大型造纸厂的废水处理工艺及运行情况。结果表明：生物酸化单元能够降低废水的ＣＯＤ、ＳＳ指标、提高废水的可生化性，还能通过较长的水力停留时间有效地调节水量与水质，从而保证了二级生物氧化的稳定与高效运行。在二极生化之后，增设水葫芦吸附墉ＣＯＤ、ＳＳ与色度、更好地保护了天然水本的环境质量，且为实现废水的深度处理与回用建立了良好的条件。     

Application of compost of two-phase olive mill waste on olive grove: Effects on soil,olive fruit and olive oil quality

Composting is a method for preparing organic fertilizers that represents a suitable management option for the recycling of two-phase olive mill waste (TPOMW) in agriculture. Four different composts were prepared by mixing TPOMW with different agro-industrial by-products (olive pruning, sheep manure and horse manure), which were used either as bulking agents or as N sources. The mature composts were added during six consecutive years to a typical “Picual” olive tree grove in the Jaén province (Spain). The effects of compost addition on soil characteristics, crop yield and nutritional status and also the quality of the olive oil were evaluated at the end of the experiment and compared to a control treated only with mineral fertilization. The most important effects on soil characteristics included a significant increase in the availability of N, P, K and an increase of soil organic matter content. The application of TPOMW compost produced a significant increase in olive oil content in the fruit. The compost amended plots had a 15% higher olive oil content than those treatment with inorganic fertilization. These organics amendments maintained the composition and quality of the olive oil.     

Wait before running for your life: defensive tactics of spiny mice (<Emphasis Type="Italic">Acomys cahirinus</Emphasis>) in evading barn owl (<Emphasis Type="Italic">Tyto alba</Emphasis>) attack

Raptor–prey encounters were studied to evaluate the strategies and success rate of both predator attack and prey defense. We compared the success of barn owls in catching stationary simulated prey (food item) with that of moving prey (food item that was pulled in various directions). We also tracked real encounters between barn owls and spiny mice in a captive environment. It was found that owls had higher success in attacking stationary prey and that they seemed to attack the prey as soon as it became motionless. When attacked, only a few spiny mice remained immobile (freeze response) whereas most fled and usually avoided capture by the owls. It was also found that spiny mice displayed a preference to escape in those directions in which owls had demonstrated a lower success in catching the simulated prey. Escape initiation dichotomized to a short or long (but rarely intermediate) distance between the spiny mouse and the owl with more successful avoidance at short-distance (last-moment) escapes. The best predictor of escape success was the velocity of the spiny mouse, and the second best predictor was its flight initiation distance (FID). We present an update for Ydenberg and Dill’s model for optimal FID in close encounters, suggesting that fleeing at the last moment is advantageous. However, a last-moment attempt to escape is also more risky with a split second differing between life and death, and is therefore appropriate mainly for agile prey under close-distance attack.     

Complexation parameters of heavy metals by olive mill wastewater determined by a cation exchange resin

Abstract

Complexing parameters in aqueous systems containing heavy metals and wastewater from olive‐oil mill (WOM) have been estimated using a cation exchange resin method. The parameters estimated were the maximum complexing ability (MCA), the stability constant (Kc) and a parameter indicating the stoichiometrical characteristics of the complex (a).

MCA of WOM for Cu, Zn, Pb and Mn was 0.470, 0.314, 0.068 and 0.300 mmol (g WOM)^‐1 respectively, and was related with the ionic radii of the various metal ions. The log Kc values followed the sequence: Cu>Pb>Zn>Mn in agreement with their respective electronegativities. In the case of Cu and Pb, data obtained here was compared with that determined in other work.     

欧版磨粉机在脱硫石灰石制粉中的应用

环保脱硫工艺中的脱硫剂大都为石灰石粉，石灰石粉的品质、细度及粒径分布是影响脱硫效果的关键性因素之一，而选择合适的石灰石粉制备的工艺和装备则对整个脱硫过程起着至关重要的作用；本文重点介绍了欧版磨粉机制备脱硫石灰石粉的技术特点及其在环保脱硫石灰石制粉中的应用。     

Cleaner production: a case study of Kaveh paper mill

The pulp and paper industry is under increasing pressure to reduce its energy consumption and impact on the environment. The ‘Cleaner Production’ (CP) approach has been widely utilised as a tool to meet environmental concerns by industry. However, because of the high initial capital cost of CP implementation, it is important to develop a model for prioritisation. In this paper, using analytic hierarchy process methodology, a tree-level hierarchy model was structured to facilitate the prioritisation process in the Kaveh Papermaking Company located in Iran. Using a literature review and field study, the proposed model can provide a framework for CP implementation in a paper factory. The results show that process change gives higher priority between 5 criteria and that repair of all leaks in the paper-making process gives higher priority between 35 sub-criteria. Process change was further evaluated and discussed in which input material changes gained higher priority. The results of this research can be used to accelerate the implementation of CP in Iran's pulp and paper industry.