- 必威体育下载

姓名
邮箱
手机号码
标题
留言内容
验证码

摘要

活性物质是典型的非平衡态系统, 其组成单元能够利用自身存储的能量或者周围环境的能量实现自驱动. 在活性系统中, 物体间的受力情况直接影响其结构和动力学行为, 因此深入了解物体间的有效作用力是理解活性物质一切复杂现象的基础. 本文通过光镊显微镜实验分别研究了活性大肠杆菌溶液中惰性球形聚苯乙烯胶体粒子间和板状粒子间的有效作用力, 发现球形粒子间有效作用力的性质一直是短程排斥力, 而板状粒子间的有效作用力则为长程吸引力, 这说明惰性粒子间的有效作用力受粒子形状的影响. 惰性粒子间的有效作用力主要来源于两部分的贡献, 即细菌-惰性粒子间的直接碰撞, 以及细菌运动产生的流场. 在实验上通过对比粒子之间、粒子外侧细菌的浓度和取向有序性发现, 球形粒子间的有效排斥力主要来源于细菌-粒子的直接碰撞, 而板状粒子间的长程吸引力则主要源于细菌流场的贡献. 本文通过光镊显微镜实验证明了惰性粒子间的有效作用力与惰性粒子的几何构型有关, 为调控活性物质中的动态自组装提供了实验支撑.

关键词:

Abstract

In active matter, the effective force between passive objects is crucial for their structure and dynamics, which is the basis for understanding the complex behaviors within active systems. Unlike equilibrium states, the factors such as the surface configuration, size, and confinement strength significantly influence the effective forces between passive particles. Previous studies have shown that the shapes of passive particles affect the aggregation of active particles, leading to different forces experienced by passive particles with different shapes. However, recently, a long-range attractive force between passive platelike particles, caused by the bacterial flow field instead of the direct bacterium-plate collisions in active bacterial suspensions, has been found. This raises an intriguing question: how does hydrodynamics affect the forces on passive particles of different shapes in different ways? In this work, we investigate the effective forces exerted on passive spherical and plate-like particles immersed in bacterial suspensions by optical-tweezers experiments. The effective force between passive particles can be calculated from the formula, $ {F_{{\text{eff}}}} = {\text{ }}k\left\langle {\Delta d} \right\rangle /2 $ , where $ \left\langle {\Delta d} \right\rangle $ represents the difference in distance between the passive particles in the bacterial bath and those in the solution without bacteria, $ k $ is the effective stiffness of optical traps. The $ {{{F}}}_{{\mathrm{e}}{\mathrm{f}}{\mathrm{f}}} > 0 $ indicates a repulsive force between passive particles, and the $ {F_{{\text{eff}}}} \lt {\text{ }}0 $ represents an effective attractive force between passive particles. Our results demonstrate that the passive spherical particles experience short-range repulsion, while plate-like particles are subjected to long-range attraction. This highlights the substantial effect of particle shape on their effective forces. The forces on passive particles are mainly attributed to two factors: direct bacterium-particle collisions and the bacterial flow field. The analysis of the bacterial concentration and orientation distribution around passive particles reveals that for spherical particles, the concentration of bacteria between particles is higher than that outside the particles, but there is almost no difference in the orientation order between bacteria inside and outside the particles. This suggests that the effective repulsion between spherical particles is mainly due to the direct bacterial collisions. Conversely, for plate-like particles, the long-range attraction is primarily influenced by the bacterial flow field rather than their direct collisions, which is evidenced by the higher bacterial density and orientation order inside the two plates compared with those outside the two plates. This study provides strong evidence that the effective force between passive particles is shape dependent in active bath, and offers new insights into controlling active-directed assembly.

Keywords:

作者及机构信息

1.
2.
3.
4.
5.
6.

通信作者:郑宁,ningzheng@bit.edu.cn; 刘鹏,liupeng@bit.edu.cn; 彭毅,pengy@iphy.ac.cn

基金项目:国家自然科学基金(批准号: 12304245, 12374205, 12074406)、油气资源与工程全国重点实验室定向课题(批准号: PRE/DX-2407)、北京凝聚态物理国家研究中心开放课题面上基金(批准号: 2023BNLCMPKF014)和中国石油大学(北京)科研基金(批准号: 2462023YJRC031)资助的课题.

Authors and contacts

1.
2.
3.
4.
5.
6.

Corresponding author:Zheng Ning,ningzheng@bit.edu.cn; Liu Peng,liupeng@bit.edu.cn; Peng Yi,pengy@iphy.ac.cn

Funds:Project supported by the National Natural Science Foundation of China (Grant Nos. 12304245, 12374205, 12074406), the National Key Laboratory of Petroleum Resources and Engineering (Grant No. PRE/DX-2407), the Beijing National Laboratory for Condensed Matter Physics, China (Grant No. 2023BNLCMPKF014), and the Science Foundation of China University of Petroleum-Beijing, China (Grant No. 2462023YJRC031).

文章全文: translate this paragraph

参考文献

[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
[23]
[24]
[25]
[26]
[27]
[28]

施引文献

下载: 全尺寸图片幻灯片

下载: 全尺寸图片幻灯片

下载: 全尺寸图片幻灯片

下载: 全尺寸图片幻灯片

下载: 全尺寸图片幻灯片

[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
[23]
[24]
[25]
[26]
[27]
[28]

[1]	石子璇, 金燕, 金奕扬, 田文得, 张天辉, 陈康.活性三嵌段共聚物的凝胶化转变. 必威体育下载 , 2024, 0(0): .doi:10.7498/aps.73.20240796
[2]	金燕, 石子璇, 金奕扬, 田文得, 张天辉, 陈康.有限多孔介质诱导活性哑铃的聚集行为. 必威体育下载 , 2024, 73(16): 160502.doi:10.7498/aps.73.20240784
[3]	王焱, 彭妙, 程伟, 彭政, 成浩, 臧圣寅, 刘浩, 任孝东, 帅雨贝, 黄承志, 吴加贵, 杨俊波.基于低损光学相变和超透镜的可控多阱光镊. 必威体育下载 , 2023, 72(2): 027801.doi:10.7498/aps.72.20221794
[4]	王晶, 焦阳, 田文得, 陈康.低惯性与高惯性活性粒子混合体系中的相分离现象. 必威体育下载 , 2023, 72(19): 190501.doi:10.7498/aps.72.20230792
[5]	高艺雯, 王影, 田文得, 陈康.空间调制的驱动外场下活性聚合物的动力学行为. 必威体育下载 , 2022, 71(24): 240501.doi:10.7498/aps.71.20221367
[6]	白靖, 葛城显, 何浪, 刘轩, 吴振森.椭圆波束对非均匀手征分层粒子的俘获特性研究. 必威体育下载 , 2022, 71(10): 104208.doi:10.7498/aps.71.20212284
[7]	仲颖, 施夏清.自驱动杆状粒子在半柔性弹性环中的集体行为. 必威体育下载 , 2020, 69(8): 080507.doi:10.7498/aps.69.20200561
[8]	王玥, 梁言生, 严绍辉, 曹志良, 蔡亚楠, 张艳, 姚保利, 雷铭.轴向多光阱微粒捕获与实时直接观测技术. 必威体育下载 , 2018, 67(13): 138701.doi:10.7498/aps.67.20180460
[9]	钱辉, 陈虎, 严洁.软物质实验方法前沿:单分子操控技术. 必威体育下载 , 2016, 65(18): 188706.doi:10.7498/aps.65.188706
[10]	陈雷鸣.干活性物质的动力学理论. 必威体育下载 , 2016, 65(18): 186401.doi:10.7498/aps.65.186401
[11]	黄雪峰, 李盛姬, 周东辉, 赵冠军, 王关晴, 徐江荣.介观尺度下活性炭微粒的光镊捕捉、点火和扩散燃烧特性研究. 必威体育下载 , 2014, 63(17): 178802.doi:10.7498/aps.63.178802
[12]	任洪亮.有限远共轭显微镜光镊设计和误差分析. 必威体育下载 , 2013, 62(10): 100701.doi:10.7498/aps.62.100701
[13]	周丹丹, 任煜轩, 刘伟伟, 龚雷, 李银妹.时间飞行法测量光阱刚度的实验研究. 必威体育下载 , 2012, 61(22): 228702.doi:10.7498/aps.61.228702
[14]	任洪亮, 丁攀峰, 李小燕.光镊轴向阱位操控及器件安装误差对径向阱位操控的影响. 必威体育下载 , 2012, 61(21): 210701.doi:10.7498/aps.61.210701
[15]	胡耿军, 李静, 龙潜, 陶陶, 张恭轩, 伍小平.时域有限差分法数值仿真单光镊中微球受到的光阱力. 必威体育下载 , 2011, 60(3): 030301.doi:10.7498/aps.60.030301
[16]	韩国霞, 韩一平.激光对含偏心核球形粒子的辐射俘获力. 必威体育下载 , 2009, 58(9): 6167-6173.doi:10.7498/aps.58.6167
[17]	杨浩, 冯国英, 朱启华, 张大勇, 周寿桓.聚焦光场俘获微球的FDTD分析. 必威体育下载 , 2008, 57(9): 5506-5512.doi:10.7498/aps.57.5506
[18]	张艳丽, 赵逸琼, 詹其文, 李永平.高数值孔径聚焦三维光链的研究. 必威体育下载 , 2006, 55(3): 1253-1258.doi:10.7498/aps.55.1253
[19]	韩一平, 杜云刚, 张华永.高斯波束对双层粒子的辐射俘获力. 必威体育下载 , 2006, 55(9): 4557-4562.doi:10.7498/aps.55.4557
[20]	降雨强, 郭红莲, 刘春香, 李兆霖, 程丙英, 张道中, 贾锁堂.低频响及低采样频率下用布朗运动分析法测量光阱刚度. 必威体育下载 , 2004, 53(6): 1721-1726.doi:10.7498/aps.53.1721

计量

文章访问数:567
PDF下载量:32
被引次数:0

搜索

留言板