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1.
规模化猪舍废气复合净化系统设计与试验 总被引:2,自引:0,他引:2
为解决规模化猪舍废气排放造成的环境污染问题,设计了一种猪舍废气复合净化系统。该系统采用化学法与水洗法相结合,通过PLC(可编程逻辑控制器)控制系统实时采集净化系统内的pH值、电导率、液位和压差等动态环境数据,智能控制洗涤泵启停和电磁阀通断,自动完成供水、加酸、喷淋和排废4个工作环节。同时,控制系统采用MCGS触摸屏与PLC建立通讯,通过创建人机交互界面实现系统环境数据监测、运行状态流动显示、按需配置系统参数和报警信息输出等多种功能,实现了系统操作的人性化和过程的可视化。系统可根据实际应用中对净化效率和运行成本的要求,实现多种控制模式,均有效抑制了猪舍废气排放。试验结果表明,系统对主要污染成分氨气的平均去除率可达到85%,整体运行可靠、控制简单,经济成本量化清晰。该系统在江西某种猪场实施应用,成效显著,可为畜禽养殖环境废气净化处理的工程应用提供参考。 相似文献
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本文以民国时期较为盛行的茶叶包装为切入点,以"泉祥"老字号茶庄的马口铁茶叶罐为研究对象,通过解读茶叶罐上的图案等蕴含的历史文化信息,梳理了"泉祥"茶庄沉浮起落的发展历程,折射了中国茶文化及工商文化的发展变迁。 相似文献
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为了研究栀子、龙胆、茵陈水煎剂对獭兔胆汁分泌和离体胆囊平滑肌肌条运动的影响,通过对獭兔实施胆管插管术,建立胆汁引流模型,应用 BL-420E 生物机能实验系统观察记录上述中药对胆汁分泌的影响;并取獭兔胆囊平滑肌,应用 HW-400S 恒温平滑肌槽和 BL-420E 生物机能实验系统,观察记录上述中药对胆囊平滑肌运动的影响。结果显示,栀子水煎剂可显著增加胆汁的分泌(P <0.05)和胆囊平滑肌收缩张力(P <0.05);龙胆和茵陈水煎剂可显著增加胆汁的分泌(P <0.05),但对胆囊平滑肌收缩张力作用不显著(P >0.05)。说明栀子、龙胆、茵陈水煎剂均可促进獭兔胆汁分泌,且栀子可提高胆囊平滑肌收缩张力,但龙胆、茵陈水煎剂对胆囊平滑肌收缩张力影响不显著。 相似文献
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Intravenous sufentanil‐midazolam versus sevoflurane anaesthesia in medetomidine pre‐medicated Himalayan rabbits undergoing ovariohysterectomy 下载免费PDF全文
Patricia Hedenqvist Marianne Jensen‐Waern Åsa Fahlman Ragnvi Hagman Anna Edner 《Veterinary anaesthesia and analgesia》2015,42(4):377-385
ObjectiveTo compare physiological effects of sufentanil-midazolam with sevoflurane for surgical anaesthesia in medetomidine premedicated rabbits.Study designProspective, randomized controlled experimental study.AnimalsEighteen female Himalayan rabbits, weight 2.1 ± 0.1 kg.MethodsPremedication with 0.1 mg kg−1 medetomidine and 5 mg kg−1 carprofen subcutaneously, was followed by intravenous anaesthetic induction with sufentanil (2.3 μg mL−1) and midazolam (0.45 mg mL−1). After endotracheal intubation, anaesthesia was maintained with sufentanil-midazolam (n = 9) or sevoflurane (n = 9). Ovariohysterectomy was performed. Intermittent positive pressure ventilation was performed as required. Physiological variables were studied perioperatively. Group means of physiologic data were generated for different anaesthetic periods. Data were compared for changes from sedation, and between groups by anova. Post-operatively, 0.05 mg kg−1 buprenorphine was administered once and 5 mg kg−1 carprofen once daily for 2–3 days. Rabbits were examined and weighed daily until one week after surgery.ResultsSmooth induction of anaesthesia was achieved within 5 minutes. Sufentanil and midazolam doses were 0.5 μg kg−1 and 0.1 mg kg−1, during induction and 3.9 μg kg−1 hour−1 and 0.8 mg kg−1 hour−1 during surgery, respectively. End-tidal sevoflurane concentration was 2.1% during surgery. Assisted ventilation was required in nine rabbits receiving sufentanil-midazolam and four receiving sevoflurane. There were no differences between groups in physiologic data other than arterial carbon dioxide. In rabbits receiving sevoflurane, mean arterial pressure decreased pre-surgical intervention, heart rate increased 25% during and after surgery and body weight decreased 4% post-operatively. Post-operative problems sometimes resulted from catheterization of the ear artery.ConclusionSevoflurane and sufentanil-midazolam provided surgical anaesthesia of similar quality. Arterial blood pressure was sustained during sufentanil-midazolam anaesthesia and rabbits receiving sevoflurane lost body weight following ovariohysterectomy. Mechanical ventilation was required with both anaesthetic regimens.Clinical relevanceAnaesthesia with sufentanil-midazolam in medetomidine premedicated healthy rabbits is useful in the clinical and the research setting, as an alternative to sevoflurane. 相似文献
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本文介绍了变频调速技术的特点,通过锅炉房风机和水泵的变频调速与挡板节流控制及其它控制方式的比较可知,变频调速有较好的节能效果。 相似文献
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Lifting for handling and flatbed truck transportation to the job site are important processes during manufacture of prefabri-cated wooden construction units like mini homes and building modules. Significant damage can occur to sections or components of units during these operations. Although damage usually will not impair its structural safety, it is costly to fix and causes the public to perceive prefabricated wooden buildings as low quality products. Field observations and preliminary numerical models for prefabri-cated units subject to lifting and transportation forces are summarized here. Once fully developed and verified, models will support the creation of damage mitigation strategies centered on structural details indicating how units are to be supported during lifting and transportation. 相似文献