数字化微混合反应器的研究

设计了一种数字化微混合反应器,对不同流体通过数字化微喷射生成微液滴,利用液滴间的碰撞和聚合实现试样与试剂间的微混合与反应。该微混合反应器由玻璃微流体器件拉制仪拉制的微管道进行粘接组合而成,内部无可动件,无需复杂的微加工技术,结构简单,制造成本低。进行了氢氧化钠溶液和酚酞溶液的混合反应实验,实验证明该混合反应器可以用于微混合反应。     

微反应器中的微制作技术

探讨了微反应器制作技术的创新与优化,分析了微反应器的基本结构与常用材料,总结了它的三种主要加工技术,即硅体微加工、超精密加工与LIGA工艺,以及四种常用的连接方法,即键合技术、高能束焊接、扩散焊与粘接,指出了在选材、加工、连接等方面应注意的问题,并给出了相应的实例,其中包括一台利用铁-铬-铝不锈钢片制作的甲醇重整制氢微反应器,它采用放电加工和湿法刻蚀技术,用扩散焊实现了连接密封,经100 h的连续试验表明,该微反应器可以与10 W的燃料电池配套使用。最后指出了目前在该领域存在的主要问题。     

用于生物微反应器pH在线监测光纤传感器研究

以生物微反应器中培养液pH在线监测为目标，研制出一种基于光度吸收原理的阵列光纤传感器。利用MEMS加工工艺，制备出传感器的阵列吸光池芯片，采用光学软件对吸光池进行优化设计，提高了传感器光传输效率，并通过CFD软件进行流体模拟，优化吸光池结构，降低了溶液死体积，缩短传感器响应时间。实验结果表明，所研究的传感器阵列检测灵敏度为0.83V/pH，响应速度快，可用于多个生物微反应器的pH在线监测。     

微电解技术在印制电路板生产综合废水处理中的应用

文章从微电解的功能和作用机制出发，介绍了微电解技术的特点、工艺和对处理印制电路板生产和电镀综合废水的适用性与优势，也介绍了改进与强化微电解作用机制的方法，对作为微电解关键技术的各种反应器作了比较性阐述，并较详细地介绍了先进的微电解膨松床的工作原理、特点、技术经济指标和操作参数。对微电解法较敏感的泥量问题，也作了分析与计算，并指出了减少泥量的途径。     

基于声表面波纸基微流器件研究

研制了压电基片上能实现样品前处理的纸基微流器件.在128°YX-LiNbO3基片上制作了1个叉指换能器和1个反射栅;亲水性纸用来制作微流器件的微通道,浸有指示剂滤纸作为微反应器,一同粘附于透明胶带上,并采用聚二甲基硅氧烷(PDMS)贴合于压电基片上.叉指换能器激发的声表面波驱动压电基片上的样品,使其输运到纸基微通道,并在纸基微反应器进行微流分析.在研制的纸基微流器件上实现了NO2-浓度的快速检测.     

用于生物微反应器pH在线监测光纤传感器研究

以生物微反应器中培养液pH在线监测为目标,研制出一种基于光度吸收原理的阵列光纤传感器。利用MEMS加工工艺,制备出传感器的阵列吸光池芯片,采用光学软件对吸光池进行优化设计,提高了传感器光传输效率,并通过CFD软件进行流体模拟,优化吸光池结构,降低了溶液死体积,缩短传感器响应时间。实验结果表明,所研究的传感器阵列检测灵敏度为0.83V/pH,响应速度快,可用于多个生物微反应器的pH在线监测。     

Fe3O4/P(St-AL)磁性微球的制备和复合微相结构

适当修饰磁性氧化铁粒子,并采用种子聚合法将苯乙烯和丙烯醛等单体的共聚控制在磁性氧化铁粒子表面,制备出内核是Fe3O4外壳为聚苯乙烯的复合微球.这种微球是一种既具有磁响应性,表面又含有反应性基团(醛基)的功能性复合微球.如果在其表面连接酶、抗体、亲和素等生物活性物质,即可制得高效、易分离的生物反应器.本文研究了Fe3O4/P(St-AL)磁性复合微球的制备及微相结构,考察了影响该微球粒径、磁响应性和表面特性的有关因素.     

用于生物微反应器pH在线监测光纤传感器研究

以生物微反应器中培养液pH在线监测为目标,研制出一种基于光度吸收原理的阵列光纤传感器.利用MEMS加工工艺,制备出传感器的阵列吸光池芯片,采用光学软件对吸光池进行优化设计,提高了传感器光传输效率,并通过CFD软件进行流体模拟,优化吸光池结构,降低了溶液死体积,缩短传感器响应时间.实验结果表明,所研究的传感器阵列检测灵敏度为0.83 V/pH,响应速度快,可用于多个生物微反应器的pH在线监测.     

LIGA技术制造微流量计的研究

介绍了利用ＬＩＧＡ技术中的同步辐射光刻、微电铸技术和微装配技术制作微流量计的研究，讨论了微流量计的结构和工作原理。设计和研制了一种微流量计。     

微电机和微动力MEMS

微执行器是微电子机械系统是一个重要的分支，本文了微执行器中的微电机，微发电机和微涡轮发动机。     

Thermal modelling of Ohmic heating microreactors

This paper describes the static and transient thermal modelling of an Ohmic heating microreactor for biological sample processing for the purpose of genetic analysis. Precise thermal management can be used for the effective preparation of analyte DNA molecules prior to detection. Due to the small dimensions of the microreactor, the direct measurement and monitoring of the temperature distribution presents a challenge. To overcome this, thermal modelling has been used to accurately predict the thermal behaviour of the microreactor and sample component. It is further possible to calculate the required input power levels and provide design criteria to optimise the design of the microreactor.     

Efficient Ni2Co4P3 Nanowires Catalysts Enhance Ultrahigh‐Loading Lithium–Sulfur Conversion in a Microreactor‐Like Battery

High‐loading lithium–sulfur (Li–S) batteries suffer from poor electrochemical properties. Electrocatalysts can accelerate polysulfides conversion and suppress their migration to improve battery cyclability. However, catalysts for Li–S batteries usually lack a rational design. A d‐band tuning strategy is reported by alloying cobalt to metal sites of Ni₂P to enhance the interaction between polysulfides and catalysts. A molecular or atomic level analysis reveals that Ni₂Co₄P₃ is able to weaken the S? S bonds and lower the activation energy of polysulfides conversion, which is confirmed with temperature‐dependent experiments. Ni₂Co₄P₃ nanowires are further fabricated on a porous nickel scaffold to unfold the catalytic activity by its large surface area. Using a simple ion‐selective filtration shell, a microreactor‐like S cathode (MLSC) is constructed to realize ultrahigh S loading (25 mg cm^?2). As such, a microreactor design integrates reaction and separation in one cell and can effectively address the polysulfide issues, the MLSC cell demonstrates excellent properties of cyclability and high capacity (1223 mAh g^?1 at 0.1 C). More importantly, the catalyst's designs and microreactor strategies provide new approaches for addressing the complicated issues of Li–S batteries.     

Highly Luminescent CdSe/ZnS Nanocrystals Synthesized Using a Single‐Molecular ZnS Source in a Microfluidic Reactor

An air‐stable, low‐toxicity, single‐molecular source for ZnS is demonstrated to be an appropriate reagent to synthesize highly luminescent ZnS‐capped CdSe with a narrow size distribution. A photoluminescence quantum yield of above 50 % and a photoluminescence peak full width at half maximum of around 32 nm could be obtained after synthesis using a microreactor. The surface of the ZnS‐capped CdSe nanocrystals can be hydrophilic, while retaining the high quantum yield. Microscopic observation shows that accurate time control, which could be achieved by using a microreactor, is important to avoid the formation of many isolated ZnS particles and the deterioration of the luminescence.     

Electrocontrolled Liquid Marbles for Rapid Miniaturized Organic Reactions

Miniaturized droplet reactors hold great promise for the development of green and sustainable chemistry. However, handling liquids with small volumes, especially viscous ones, in a convenient and loss‐free manner remains a challenge. Here, by electrically controlling the coalescence and mixing of particle‐coated droplets, also known as liquid marbles, an effective microreactor is demonstrated for miniaturized chemical reactions involving viscous reagents. By applying an electric voltage to marbles, the induced electromixing of marble microreactors promotes the reaction rate and the product yield. The advantages of electromixed marble reactors are manifested by a series of chemical reactions between aldehydes and 2‐methylindole in viscous glycerol solution. The electrically‐controlled coalescence and mixing establish liquid marbles as microreactors for rapid, efficient, and miniaturized chemical reactions.     

Metal Doped Core–Shell Metal‐Organic Frameworks@Covalent Organic Frameworks (MOFs@COFs) Hybrids as a Novel Photocatalytic Platform

Metal doped core–shell Metal‐Organic Frameworks@Covalent Organic Frameworks (MOFs@COFs) are presented as a novel platform for photocatalysis. A palladium (Pd) doped MOFs@COFs in the form of Pd/TiATA@LZU1 shows excellent photocatalytic performance for tandem dehydrogenation and hydrogenation reactions in a continuous‐flow microreactor and a batch system, indicating the great potential of the metal doped MOFs@COFs as a multifunctional platform for photocatalysis. Explanations for the performance enhancement are elucidated. An integrated dual‐chamber microreactor coupled with the metal doped MOFs@COFs is introduced to demonstrate a concept of an intensified green photochemical process, which can be broadly extended to challenging liquid–gas tandem and cascade reactions.     

Compartmentalization within Self‐Assembled Metal–Organic Framework Nanoparticles for Tandem Reactions

Compartmentalization is an essential feature found in living cells to ensure multiple biological processes occur without being affected by undesired external influences. Here, compartmentalized systems are developed based on the self‐assembly of metal–organic framework (MOF) nanoparticles into multifunctional MOF capsules (MOF‐Cs). Such MOF‐Cs have the capability of controlling molecular transportation and protecting interior microenvironment, thus making tandem reaction along trajectories to desired products. First of all, MOF‐Cs present controlled molecular transportation derived from molecular sieving property of MOFs. Second, MOF‐Cs can protect the encapsulated cargoes from denaturation and maintain their catalytic activity. Third, MOF‐Cs can provide spatial segregation for incompatible species and facilitate communication between these compartments to perform tandem reactions. These compartmentalized structures offer new views in the transportation, microreactor, and biotechnology.     

Towards the CFD model of flow rate dependent enzyme-substrate reactions in nanoparticle filled flow microreactors

Measurable kinetic parameters of enzyme-substrate reactions in the presence of immobilized biocatalysts in flow microreactors show remarkable dependence on the substrate flow rate. This paper presents a computational model that operates with a flow rate dependent K_M value. CFD simulations and actual measurements were carried out in a chip microreactor, investigating the chemical process of deamination of phenylalanine by the model enzyme PfXAL attached to the surface of magnetic nanoparticles, forming packed bed reactors in the microfluidic chip. The reactor geometry has been varied in order to examine the flow rate dependence of the reaction. Experimental results suggested a moderate flow rate dependence of the examined kinetic parameters. The volumetric product concentration distribution was calculated in the reactors by CFD simulations, created with the open source software OpenFOAM, to enable further optimizations of the chip structure, enabling the design of more reliable flow reactors.     

Controllable Thermochemical Generation of Active Defects in the Horizontal/Vertical MoS2 for Enhanced Hydrogen Evolution

As for 2D transition metal dichalcogenides, the creation of proper active defects concentrations is considered as the efficient strategy for improving hydrogen evolution performance. However, the synthesis methods of large-area MoS₂ catalysts with controllable active defects are limited, also for its working mechanism. Herein, thermochemical generation of active defects for MoS₂ catalysts has established by annealing sodium hypophosphite, in which the phosphine is spontaneously generated and chemically tailors the MoS₂ lattice. The defects formation is confirmed by the investigation of slightly-changed surface structure and unpaired electrons for the annealed samples. The hydrogen evolution reaction performances of horizontally/vertically grown MoS₂ films are improved by controlling reaction conditions, indicating the active defects could form in the basal plane and edges with retained crystal structure. The overpotential of MoS₂ samples converted from 10 nm Mo reduces from −520 to −265 mV with largely decreased Tafel slope. The electrochemical microreactor studies reveal the protons adsorption of active sites shows much more significant contribution, than interfacial charge transfer with the enhanced remarkable performance (−100 mV at 10 mA cm⁻²). This study presents the large-area synthesized strategy for MoS₂ based catalysts with controllable defects concentration and helps establish rational design principles for future MoS₂ family electrocatalysts.     

Constructing the Support as a Microreactor and Regenerator for Highly Active and In Situ Regenerative Hydrogenation Catalyst

The demands for efficient and robust heterogeneous hydrogenation catalysts have triggered extensive research to optimize the structures of metal catalytic centers, but the potential of support construction for enhanced hydrogenation performance has been overlooked. This study introduces a hierarchically ordered porous poly(2,6-diaminopyridine) (PDAP) as a Pd nanoparticle support for hydrogenation removal of recalcitrant pollutants in water purification. The PDAP support acts as a sorbent and microreactor to enhance the proximity of targeted water pollutants and reactive hydrogen atom species, achieving unprecedently high water purification efficiency. The PDAP support also acts as a catalyst in mediating peroxide-activation for oxidative destruction of Pd poisons (e.g., reduced sulfur), achieving in situ regeneration of poisoned Pd catalysis centers. The high activity and in situ regenerativity achieved by rational construction of the support structure sheds light on a new approach for designing efficient and robust heterogeneous hydrogenation catalysts.     

Microfluidic‐Spinning‐Directed Microreactors Toward Generation of Multiple Nanocrystals Loaded Anisotropic Fluorescent Microfibers

Anisotropic fluorescent hybrid microfibers with distinct optical properties and delicate architectures have aroused special interest because of their potential applications in tissue engineering, drug delivery, sensors, and functional textiles. Microfluidic systems have provided an ideal microreactor platform to produce anisotropic fibers due to their simplified manipulation, high efficiency, flexible controllability, and environmental‐friendly chemical process. Here a novel microfiber reactor based on a microfluidic spinning technique for in situ fabrication of nanocrystals loaded anisotropic fluorescent hybrid microfibers is demonstrated. Multiple nanocrystal reactions are carried out in coaxial flow‐based microdevices with different geometric features, and various nanocrystals loaded microfibers with solid, string‐of‐beads and Janus topographies are obtained. Moreover, the resulted anisotropic fluorescent hybrid microfibers present multiple optical signals. This strategy contributes a facile and environmental‐friendly route to anisotropic fluorescent hybrid microfibers and might open a promising avenue to multiplex optical sensing materials.