基于仿生学的植物气孔高效扩散效应的研究

发布时间：2018-05-21 11:56

本文选题：植物叶片气孔 + 小孔扩散率　；参考：《安徽农业大学》2014年硕士论文

【摘要】：植物是支撑地球生物圈的第一生产者,它有着很多与我们人类和其他生命形态截然不同的生命活动特点,这些特定生命现象的发生场所大多就在植物叶片的气孔中。本文从仿生学的视觉出发,借鉴植物叶片气孔高效扩散效应和选择性通透的一系列特征,将锌空气电池作为工作载体,以实验探索与理论分析两者相结合的手段,通过研究锌空气电池在不同环境下的失水情况和覆盖仿生叶片对其失水和工作的影响,初步探索了氧气和水蒸汽在通过微米级小孔时所表现出来的不同现象及其机理。本文的主要工作包括：第一,改变环境温度、相对湿度和空气流通速度这三种环境因素,探索了环境因素对锌空气电池失水的影响,并进一步证明了“失水”在锌空气电池的工作中的紧要性；第二,制作仿生叶片,并覆盖于锌空气电池之上,通过恒流放电,验证这层仿生叶片能否在电池的工作中起到“保水透气”的作用;第三,从仿生叶片和电池工作的环境状态、水蒸汽和氧气的扩散参数和物理、化学特性等角度综合解释了出现这一现象的原因。得出的主要结论总结如下：(1)在一般情况下,锌空气电池工作过程中的失水量会随着相对湿度的增加而降低,随着环境温度的上升而增大。当环境温度达到70±1℃,相对湿度为30%±5%时,电池因工作失水导致其自身含水量小于50%,此时电池将无法正常工作。(2)在仿生叶片微孔间距小于临界间距时,叶片并不会阻碍氧气的传输,同时,覆盖仿生叶片可使锌空气电池放电的失水量减少40%-80%。失水量随着微孔数目的减少而降低,当微孔间距达到临界点时,电池的失水量达也同时到最小值。随着电池失水的减少,电压衰减变得缓慢,电池工作更加稳定。在微孔数目的临界范围内,这个值越少,电池的放电性能也会越好。(3)在环境温度为20℃,相对湿度为60%,空气流通速度为7.0m/s时,考虑气体浓度差,氧气在仿生叶片上的扩散能力远高于水蒸汽在仿生叶片上的扩散能力。这是因为在分子间相互作用强烈时,水分子的极性会表现出来,在通过微孔时,它的能力会明显低于非极性的氧气分子。在宏观上就表现为水蒸汽分子碰撞扩散时通过微孔时的阻力更大,扩散量也明显低于氧气的扩散量。
[Abstract]:Plant is the first producer to support the earth's biosphere. It has a lot of life activities which are very different from our human beings and other life forms. Most of these specific life phenomena occur in the stoma of plant leaves. This paper, based on the vision of bionics, uses the effect and selectivity of the stomata of plant leaves to be efficient and selective. A series of characteristics, the zinc air battery is used as the working carrier, and the experimental exploration and theoretical analysis are combined. By studying the water loss of the zinc air battery under different environment and the influence of the bionic leaf on its water loss and work, the oxygen gas and the water vapor are preliminarily explored in the micron hole. The main work of this paper is as follows: first, change the environmental temperature, relative humidity and air circulation speed and three environmental factors, explore the effect of environmental factors on the loss of water of zinc air battery, and further prove the importance of "water loss" in the work of zinc air battery; second, making bionics The blade is covered in the zinc air battery. Through the constant current discharge, it is proved that the bionic blade can play the role of "keeping water and breathable" in the work of the battery. Third, this phenomenon is explained comprehensively from the environmental state of the bionic blades and batteries, the diffusion parameters of water vapor and oxygen, the physical and chemical properties of the water vapor and oxygen. The main conclusions are summarized as follows: (1) in general, the amount of water loss in the working process of zinc air battery will decrease with the increase of relative humidity and increase with the increase of ambient temperature. When the environment temperature reaches 70 + 1 C and the relative humidity is 30% + 5%, the water loss of the electric pool is less than 50% because of the water loss. The battery will not work normally. (2) when the micropore space of the bionic blade is less than the critical distance, the blade does not obstruct the transmission of oxygen. At the same time, the bionic blade can reduce the water loss of the zinc air battery discharge and decrease the water loss of 40%-80%. with the decrease of the number of micropores. When the micropore space reaches a critical point, the amount of water loss of the battery reaches the limit. At the same time, the minimum value. With the decrease of battery water loss, the voltage attenuation becomes slow and the battery work is more stable. The less the number of micropores, the better the discharge performance of the battery. (3) when the ambient temperature is 20, the relative humidity is 60%, the air flow velocity is 7.0m/s, the oxygen is in the bionics considering the gas concentration difference. The diffusion capacity on the blade is much higher than the diffusion capacity of the water vapor on the bionic blade. This is because the polarity of the water molecules is manifested when the intermolecular interaction is strong, and the capacity of the water molecules is obviously lower than that of the nonpolar oxygen molecules when they pass through the micropores. In the macroscopic view, the vapor molecules are passing through the micropores when the molecules collide and diffuse. The resistance is greater, and the amount of diffusion is also significantly lower than that of oxygen.
【学位授予单位】：安徽农业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM911.41

【共引文献】