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91.
通过对家庭居室不同空间特点的分析,根据家庭绿化的趋势,从绿化植物材料的适应性、观赏性、生态性和经济性方面探讨了家庭绿化材料的选择,以期为居室绿化提供参考依据。 相似文献
92.
乡镇污水处理厂运行管理相关问题探讨 总被引:1,自引:0,他引:1
乡镇污水处理厂作为环保基础设施建设的重点,普遍存在重建设轻运营的问题。笔者结合重庆市实际情况,重点分析了乡镇污水处理厂运行管理中存在的问题,并有针对性地提出了建议,包括提高收集率、完善末端工艺、专业化运营、改变考核体系、优化污泥处置、加强再生利用和远程在线监控等。 相似文献
93.
通过对南粤地区6个居住区园林工程项目的绿化设计进行调查,收集南粤居住区常用的植物种类以及使用量,此总结了居住区绿地规划设计中园林植物品种选择的规律,为华南地区园林苗圃的生产提供参考。 相似文献
94.
Francili A. Molossi Bianca S. de Cecco Camila B. Pohl Rogrio B. Borges Luciana Sonne Saulo P. Pavarini David Driemeier 《Journal of veterinary diagnostic investigation》2021,33(4):677
We determined the prevalence of diseases and pathogens associated with mortality in beef cattle in the State of Rio Grande do Sul, Brazil, based on pathology laboratory submissions. Postmortem examinations were conducted on 1,277 beef cattle that died between 2008 and 2018. Information regarding age, time of the year, breed, and regional location were analyzed statistically. Most cattle were from the surrounding region of Porto Alegre, and 78.7% of the analyzed cases had diagnostic value. The diagnostic category with most cases was infectious and/or parasitic diseases (60%), followed by toxic and toxicoinfectious (25%). Most cases occurred in the fall. Major disease conditions identified included hemoprotozoal infection (18.2%), rabies (8.2%), and plant intoxications by Senecio spp. (8.5%) and Pteridium arachnoideum (4.6%). Hemoprotozoal infection occurred at a higher frequency in young cattle, mainly in animals up to 1 y old. Intoxication by Senecio spp. was more frequent in cattle 2–3 y old. 相似文献
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97.
Marco Grella Fabrizio Gioelli Paolo Marucco Ingrid Zwertvaegher Eric Mozzanini Marco Pittarello Paolo Balsari Spyros Fountas David Nuyttens Monica Mezzalama Massimo Pugliese 《Pest management science》2023,79(11):4423-4438
Background
In order to improve the biological control agent (BCA) efficacy, stress factors threatening the viability of microorganisms during spray application need to be determined. The effect of spray mixture temperature and exposure time on Trichoderma harzianum T 22 and Bacillus amyloliquefaciens QST713 viability were tested. Concurrently the combined effect of mechanical and thermal stress effect on BCA viability were tested at two initial spray mixture temperatures (14 and 25 °C) by simulating a spray application using airblast sprayers featured by different tank capacity and a spray liquid circuit (without and with hydraulic agitation system). To assess the BCA microorganism viability, spray mixture samples were collected at time intervals along trials and plated to count the colony forming units (CFU).Results
The critical temperature threshold that inhibited BCA viability was 35 °C with 30 min of exposure. The sprayer type, the initial temperature of the spray mixture and the temperature increment during the trials significantly decreased the number of CFU recovered. When simulating a spray application, the spray mixture temperature increase rate was determined mainly by the residual amount of spray mixture in the tank. Even if the tank capacity does not substantially affect the final temperature reached by the spray mixture, the higher residual spray mixture in bigger tanks can expose the BCAs for a longer time to critical temperatures.Conclusions
Experimental trials allowed us to identify the effect of factors affecting the viability of tested BCAs, providing information about the actual chance to guarantee the biological efficacy of BCA treatments. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献98.
沙棘组织培养与植株再生研究 总被引:3,自引:0,他引:3
孙兰英 《国际沙棘研究与开发》2004,2(2):28-30
将不同沙棘品种顶端分生组织接种于不同激素浓度的培养基上进行培养,试验结果表明,沙棘顶端分生组织的生长不仅需要低无机盐的培养基,而且需要较低水平的激素物质,无激素或激素浓度偏高都将导致外植体的死亡。 相似文献
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100.
With the development of the economy, the demand forhabitation is enhanced and the sewage and industrial waster water must be disposed before outlet. Today, most of the sewage treatment plants are built on the aboveground without discussing the underground. Therefore, by the comparative analysis of the property and cost of the underground sewage treatment plant and the ground, the underground sewage treatment plant have merits in save the city land and improvement environment.The Chongqing citypossess a lot of advantages in using the space of underground with the analysis of the physiognomy and geology condition of the Chongqing city. Therefore, the development of underground sewage treatment plant is feasible in the Chongqing city. 相似文献