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【目的】研究猕猴桃授粉雾化粒径对花粉粒沉积分布的影响,探寻授粉适宜的雾化粒径范围,为建立猕猴桃液体授粉方法提供理论支持。【方法】构建双流式喷雾试验平台,在雾化气压为0.025~0.150 MPa、花粉液流量为0.125 L/min、喷雾时长为0.1 s、喷雾距离为350 mm的喷雾控制参数下进行试验。采用自制雾滴收集器,用称质量法测定单次喷射体积,分析雾化气压对单次喷射体积的影响;用激光粒度仪测量雾化粒径值,建立雾化气压与雾化粒径的关系;用雾滴环形采集片代替花朵采集花粉悬浊液雾滴,通过显微镜分区计数法,明确花粉粒沉积数量在花蕊区和花瓣区的沉积特征;以充分授粉需求花粉粒数为判断标准,确定适宜双流式雾化授粉的花粉液雾化粒径控制范围。【结果】猕猴桃花粉液单次喷射体积与单次喷出的花粉粒数均随雾化气压的增大而减小,当雾化气压为0.150 MPa时,花粉液单次喷出体积最小,为185.9μL,单次喷出花粉粒数也最小,为15.7万粒;雾化粒径与雾化气压呈非线性负相关关系,雾化气压为0.025~0.150 MPa时对应的雾化粒径为92.8~28.2μm;花蕊区和花瓣区花粉液雾滴沉积质量都随雾化粒径的增加... 相似文献
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设计一种气助式静电感应喷头,对其工作原理和关键结构进行了研究。在室内对它进行了雾化性能试验和荷电效果试验。由试验结果分析了充电电压、气体压力与流量、液体压力与流量、喷孔直径等参数对雾化质量和荷电效果的影响,综合分析气体压力为0.4 MPa,液体压力为0.25 MPa,喷孔直径为2.0 mm时气助式静电感应喷头具有最优化性能。 相似文献
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Based on Eulerian Lagrangian coupling algorithm, the performance parameters of Fan shaped air blast atomizer is simulated. It is shown that when gas liquid mass flow ratio is constant, the spray angle and velocity of droplet decreases and SMD increases gradually with the increase of orifice width. Therefore, in order to obtain much smaller liquid droplet, orifice width should not be too wide. When the orifice width is constant, along with the increase of gas liquid mass flow ratio, SMD decreases firstly and increases later when reaching the minimum. And SMD minimum value is 39.5 μm when the orifice width is 0.6 mm. 相似文献
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Development model of emulsified oil jet and micro-explosion properties of water drops are analyzed,cavitation effect can change the jet atomizing angle,therefore,an important guideline to describe oil jet atomization is atomizing angle. Absolute diesel fuel and different moisture content emulsified diesel fuels are researched by high-speed camera system from the experiment for studying the atomizing properties of water drops when high-voltage impulse injects the gas medium. The theory and experimental results show that lots of water drops of emulsified oil reduce jet dynamic strength when the jet unloads,so it has stronger dispersed properties. Emulsified diesel fuel can spray more capacity than absolute diesel fuel,the width of jet is greater and the spraying atomizing angle increases. When the moisture percent of emulsified oil is 10%,the atomizing angle can get to the maximum. 相似文献
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应用0.5%蜂胶乳液蒸气雾化吸入治疗急性咽喉炎165例,显效以上131例,占79.39%;与常规用药蒸气雾化吸入治疗177例,显效以上149例,占84.18%进行比较,差异无显著性(P>0.05)。观察证明,蜂胶具有明显抗菌、抗病毒及镇痛作用,对急性咽喉炎疗效满意。 相似文献
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《Veterinary anaesthesia and analgesia》2023,50(3):255-262
ObjectiveTo investigate the sedative and cardiorespiratory effects of intranasal atomization (INA) of alfaxalone using a mucosal atomization device in Japanese White rabbits.Study designRandomized, prospective, crossover study.AnimalsA total of eight healthy female rabbits, weighing 3.6–4.3 kg and aged 12–24 months.MethodsEach rabbit was randomly assigned to four INA treatments administered 7 days apart: Control treatment, 0.15 mL 0.9% saline in both nostrils; treatment INA0.3, 0.15 mL 4% alfaxalone in both nostrils; treatment INA0.6, 0.3 mL 4% alfaxalone in both nostrils; treatment INA0.9, 0.3 mL 4% alfaxalone in left, then right, then left nostril. Sedation was scored 0–13 using a composite measure scoring system for rabbits. Simultaneously, pulse rate (PR), respiratory rate (fR), noninvasive mean arterial pressure (MAP), peripheral hemoglobin oxygen saturation (SpO2) and arterial blood gases were measured until 120 minutes. The rabbits breathed room air during the experiment and were administered flow-by oxygen when hypoxemia (SpO2 <90% or PaO2 <60 mmHg; 8.0 kPa) developed. Data were analyzed using the Fisher's exact test and the Friedman test (p < 0.05).ResultsNo rabbit was sedated in treatments Control and INA0.3. All rabbits in treatment INA0.9 developed loss of righting reflex for 15 (10–20) minutes [median (25th–75th percentile)]. Sedation score significantly increased from 5 to 30 minutes in treatments INA0.6 and INA0.9 with maximum scores of 2 (1–4) and 9 (9–9), respectively. fR decreased in an alfaxalone dose-dependent manner and one rabbit developed hypoxemia in treatment INA0.9. No significant changes were observed in PR and MAP.Conclusions and clinical relevanceINA alfaxalone resulted in dose-dependent sedation and respiratory depression in Japanese White rabbits to values considered not clinically relevant. Further investigation of INA alfaxalone in combination with other drugs is warranted. 相似文献