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1.
An evaluation of fresh gas flow rates for spontaneously breathing cats and small dogs on the Humphrey ADE semi‐closed breathing system 下载免费PDF全文
ObjectiveTo evaluate the fresh gas flow (FGF) rate requirements for the Humphrey ADE semi-closed breathing system in the Mapleson A mode; to determine the FGF at which rebreathing occurs, and compare the efficiency of this system to the Bain (Mapleson D) system in spontaneously breathing cats and small dogs.Study DesignProspective clinical study.AnimalsTwenty-five healthy (ASA score I or II) client-owned cats and dogs (mean ± SD age 4.7 ± 5.0 years, and body weight 5.64 ± 3.26 kg) undergoing elective surgery or minor procedures.MethodsAnaesthesia was maintained with isoflurane delivered via the Humphrey ADE system in the A mode using an oxygen FGF of 100 mL kg−1 minute−1. The FGF was then reduced incrementally by 5–10 mL kg−1minute−1 at approximately five-minute intervals, until rebreathing (inspired CO2 >5 mmHg (0.7 kPa)) was observed, after which flow rates were increased. In six animals, once the minimum FGF at which rebreathing occurred was found, the breathing system was changed to the Bain, and the effects of this FGF delivery examined, before FGF was increased.ResultsRebreathing did not occur at the FGF recommended by the manufacturer for the ADE. The mean ± SD FGF that resulted in rebreathing was 60 ± 20 mL kg−1minute−1. The mean minimum FGF at which rebreathing did not occur with the ADE was 87 ± 39 mL kg−1minute−1. This FGF resulted in significant rebreathing (inspired CO2 8.8 ± 2.6 mmHg (1.2 ± 0.3 kPa)) on the Bain system.ConclusionsThe FGF rates recommended for the Humphrey ADE are adequate to prevent rebreathing in spontaneously breathing cats and dogs <15 kg.Clinical relevanceThe Humphrey ADE system used in the A mode is a more efficient alternative to the Bain system, for maintenance of gaseous anaesthesia in spontaneously breathing cats and small dogs. 相似文献
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Most real power systems are not radial networks and evaluation of the stability often needs to establish electromagnetic transient simulation models. So the network equivalent is required first and foremost. The adjacent two-node equivalent method, which considers the coupling impedance between equivalent nodes, is used to realize the simplification and modeling to complex power grid. The analysis and simulation on both the HVDC system from Deyang to Baoji and a real extra-high voltage AC transmission system in South China shows that the static performance of the simulated system by using the adjacent two-node equivalent method is completely equivalent to the original one, as well as the performance of dynamic equivalent is in a satisfied level. Thus the transient system model simplified can be well established to support research of power grid’s security and stability. 相似文献
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传感器节点自主供电的环境混合能量收集系统设计 总被引:1,自引:1,他引:0
农田复杂环境及大面积监测需求对农业物联网传感器节点的供电提出了极大挑战,而环境能量收集技术则使低功耗农业物联网传感器节点的自供电及免维护成为可能。针对传统能量收集装置中收集的环境能量单一有限、装置体积大、可靠性差的问题,该文提出了一种新型混合环境能量一体化收集系统。该系统定位于环境中普遍而丰富的射频电磁波能量和振动能量,通过射频收集天线和压电陶瓷的有效结合,同时收集2种环境能量,并经整流转换成直流电能。能量收集天线使用普通FR4印刷电路板实现,工作在手机通信频段1.9 GHz(3G频段),测试的回波损耗为-20.5 d B,对电磁波能量收集的最高输出功率可达到38 mW,测得收集到的振动能量最大输出功率可达到25 mW,满足低功耗传感器节点的功率需求。该装置不仅可以有效提高系统供电的可靠性和对环境的适应能力,还大大降低了传统混合系统的尺寸,可为农业物联网快速发展中的传感器节点可靠供电问题提供参考。 相似文献
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Wen Zhiyu Huang Youshu Yuan Xianghui He Qingyi 《保鲜与加工》1992,(4):26-30
The paper studies a self- scanned circuit used in MOS image sensor with the demand of developing of high -order.low power disspation MOS image sensor and puts forward a kind of self -scanned circuit .which uses a three tramister dynamic nocomparing circuit whith a changing capacitor bootstrap circuit as MOS image sensor. The circuit adopted a silicon gote P -MOS technique, which is a high -speed low-dissipation dynamic no-coparing circuit. It is a practical unit circuit in the high -order array and solves the problem that the power dissipation of array rises with the increase of the array bite. 相似文献
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[目的]利用空间技术解析黑龙江省宁安市和盛小流域水土保持措施的布设,为低山丘陵区小流域水土流失综合治理提供技术支撑。[方法]在实地调查和现场踏查基础上,利用ArcGIS 9.3的空间分析功能,结合土地利用图和谷歌遥感影像分析小流域土地利用随地形的空间分布数量信息,并对水土流失治理效益进行评估。[结果]根据分析结果确定该流域防治措施主要包括地埂植物带、保土耕作、侵蚀沟防护林、谷坊、生态修复、五孔涵过水路面桥和涵洞等,治理效益显著。[结论]和盛小流域水土流失综合治理项目经济内部收益率大于社会折现率,经济净现值大于0,效益费用比大于1,工程采用的水土保持技术和方法符合国家和部门相关标准和技术规范,切合当地实际,可为同类地区水土流失治理借鉴。 相似文献
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吉文林 《农产品加工.学刊》2005,(Z1)
产学研一体化是当今高职教育与产业的“结合部”,也是高职教育发展的潮流。只有面向企业办学校,围绕市场办专业,结合专业办产业,办好产业促专业,高职院校才有生命力。 相似文献
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对偏调谐类单调谐滤波器提出了非线性的束优化模型,运用大系统理论协调优化单调谐滤波器和高通滤波器,实例计算表明,该方法是对以往单调谐滤波器设计计算方法的一大改进。 相似文献
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喇国玮 《山东省农业管理干部学院学报》2002,(4)
学风问题是关系到中国共产党的兴衰和社会主义事业成败的重大问题。新时期,我们要进一步加强学风建设, 大力弘扬马克思主义学风,坚持理论联系实际,推动社会主义现代化建设事业不断发展。 相似文献