抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

1. Introduction 20642. Synthesis of Magnetic Nanoparticles 20662.1. Classical Synthesis by Coprecipitation 20662.2. Reactions in Constrained Environments 20682.3. Hydrothermal and High-TemperatureReactions20692.4. Sol-Gel Reactions 20702.5. Polyol Methods 20712.6. Flow Injection Syntheses 20712.7. Electrochemical Methods 20712.8. Aerosol/Vapor Methods 20712.9. Sonolysis 20723. Stabilization of Magnetic Particles 20723.1. Monomeric Stabilizers 20723.1.1. Carboxylates 20733.1.2. Phosphates 20733.2. Inorganic Materials 20733.2.1. Silica 20733.2.2. Gold 20743.3. Polymer Stabilizers 20743.3.1. Dextran 20743.3.2. Polyethylene Glycol (PEG) 20753.3.3. Polyvinyl Alcohol (PVA) 20753.3.4. Alginate 20753.3.5. Chitosan 20753.3.6. Other Polymers 20753.4. Other Strategies for Stabilization 20764. Methods of Vectorization of the Particles 20765. Structural and Physicochemical Characterization 20785.1. Size, Polydispersity, Shape, and SurfaceCharacterization20795.2. Structure of Ferro- or FerrimagneticNanoparticles20805.2.1. Ferro- and Ferrimagnetic Nanoparticles 20805.3. Use of Nanoparticles as Contrast Agents forMRI20825.3.1. High Anisotropy Model 20845.3.2. Small Crystal and Low Anisotropy EnergyLimit20855.3.3. Practical Interests of Magnetic NuclearRelaxation for the Characterization ofSuperparamagnetic Colloid20855.3.4. Relaxation of Agglomerated Systems 20856. Applications 20866.1. MRI: Cellular Labeling, Molecular Imaging(Inﬂammation, Apoptose, etc.)20866.2.

Magnetic Iron Oxide Nanoparticles: Synthesis, Stabilization, Vectorization, Physicochemical Characterizations, and Biological Applications

Over the past few decades, researchers have established artificial enzymes as highly stable and low-cost alternatives to natural enzymes in a wide range of applications. A variety of materials including cyclodextrins, metal complexes, porphyrins, polymers, dendrimers and biomolecules have been extensively explored to mimic the structures and functions of naturally occurring enzymes. Recently, some nanomaterials have been found to exhibit unexpected enzyme-like activities, and great advances have been made in this area due to the tremendous progress in nano-research and the unique characteristics of nanomaterials. To highlight the progress in the field of nanomaterial-based artificial enzymes (nanozymes), this review discusses various nanomaterials that have been explored to mimic different kinds of enzymes. We cover their kinetics, mechanisms and applications in numerous fields, from biosensing and immunoassays, to stem cell growth and pollutant removal. We also summarize several approaches to tune the activities of nanozymes. Finally, we make comparisons between nanozymes and other catalytic materials (other artificial enzymes, natural enzymes, organic catalysts and nanomaterial-based catalysts) and address the current challenges and future directions (302 references).

Nanomaterials with enzyme-like characteristics (nanozymes): next-generation artificial enzymes

https://cyberleninka.org/article/n/999493.pdf

New trends in removing heavy metals from industrial wastewater

UV-Visible ار راد ن .د TiO2 ( تیفرظ راون مان هب نورتکلا یاراد یژرنا زارت لماش VB و ) رگید زارت ی یژرنا اب ( ییاناسر راون مان هب نورتکلا زا یلاخ و رتلااب VB یم ) .دشاب ت ود نیا نیب یژرنا توافت یژرنا فاکش زار ، پگ دناب هدیمان یم .دوش هک ینامز زا نورتکلا لاقتنا VB هب VB یم ماجنا دریگ ، TiO2 اب ودح یژرنا بذج د ev 2 / 3 ، نورتکلا تفج کی دیلوت یم هرفح .دیامن و نورتکلا هرفح ی نا اب هدش دیلوت یم کرتشم حطس هب لاقت ثعاب دناوت شنکاو ماجنا اه یی ددرگ . TiO2 دربراک ،دراد یدایز یاه هلمج زا یم ناوت اوه یگدولآ هیفصت یارب (CO2) و بآ و ... نآ زا هدافتسا درک .

Advanced Nanoarchitectures for Solar Photocatalytic Applications

In this work, we have systematically analyzed the scaling law of droplet formation by cross-flow shear method in T-junction microfluidic devices The droplet formation mechanisms can be distinguished by the capillary number for the continuous phase (Cac), which are the squeezing regime (Cac < 0002), dripping regime (001 < Cac < 03), and the transient regime (0002 < Cac< 001) Three corresponding correlations have been suggested in the different range of Cac In the dripping regime, we developed a modified capillary number for the continuous phase (Cac′) by considering the influence of growing droplet size on the continuous phase flow rate And the modified model could predict droplet diameter more accurately In the squeezing regime, the final plug length was contributed by the growth and ‘squeeze’ stages based on the observation of dynamic break-up process In the transient regime, we firstly suggested a mathematical model by considering the influences of the above two mechanisms The correlations should be very useful for the application of controlling droplet size in T-junction microfluidic devices

Correlations of droplet formation in T-junction microfluidic devices: from squeezing to dripping

In our previous work, a new flow route was developed—a so-called perpendicular shear force–induced droplet formation—in a self-designed simple T-junction microchannel device. In this work, the crossflowing rupture technique was used to prepare monodisperse droplets in a similar device and successfully prepared monodisperse droplets ranging from 50 to 500 μm with polydispersity index (σ) values of <2%. Two kinds of flow patterns of plug flow and drop flow in the T-junction microchannels could be formed. By changes in the surfactant concentration, the interfacial tension and the wetting ability varied, and the disordered or ordered two-phase flow patterns could be controlled. Evolutions of the contact angle of the oil in contact with the wall surface were explained by the adsorption of surfactant molecules to the solid–liquid interface. The increase of continuous phase flow rate and viscosity resulted in the decrease of the droplet size, and the droplet size was correlated with capillary number Ca. By comparing the variation range of drop size using the two methods, it was found that the method of perpendicular flow-induced droplet formation can control the drop size over a much wider range. © 2006 American Institute of Chemical Engineers AIChE J, 2006

Preparation of highly monodisperse droplet in a T-junction microfluidic device

Perpendicular flow is used to induce oil droplet breakup by using a capillary as water phase flow channel. It is a new route to produce monodisperse emulsions. The wetting properties of the fluids on the walls are exceedingly important parameters. Depending on the oil and water flow rates, different spatial distributions of the two phases as laminar, plugs, cobbles and drops, are obtained. The effects of two-phase flow rates on plugs and drop size are studied, and the different droplet formation mechanisms of plug flow and drop flow are discussed. Two quantitative equations utilized to predict the droplet size are developed.

Shear force induced monodisperse droplet formation in a microfluidic device by controlling wetting properties

Chitosan nanoparticles with magnetic properties can be potentially used as drug delivery carrier, separation materials. Different from the two-step preparation method of suspension cross-linking, a new method was proposed to in situ prepare magnetic chitosan/Fe3O4 composite nanoparticles with tiny water pools of water-in-oil microemulsion containing chitosan and ferrous salt as microreactors by adding the basic precipitant of NaOH into the microemulsion. The images of transmission electron microscope showed that the cubic-shape magnetic iron oxide particles were encapsulated by the spherical chitosan nanoparticles. The chitosan particle size varied from 10 nm to 80 nm with different molecular weight of chitosan. The saturated magnetization of pure Fe3O4 nanoparticles was as high as 120 emu/g, and the saturated magnetization of composite nanoparticles could reach 11.15 emu/g. Meanwhile, the nanoparticles showed the characteristics of superparamagnetism. We may adjust the magnetization of composite particles by changing the weight ratio of chitosan and Fe3O4. After stirring in water for 48 h the composite nanoparticles showed the same magnetization as the original ones, indicating high stability of the composite nanoparticles.

In situ preparation of magnetic chitosan/Fe3O4 composite nanoparticles in tiny pools of water-in-oil microemulsion

The past two decades have witnessed a rapid development of microreactors. A substantial number of reactions have been tested in microchemical systems, revealing the advantages of controlled residence time, enhanced transport efficiency, high product yield, and inherent safety. This review defines the microchemical system and describes its components and applications as well as the basic structures of micromixers. We focus on mixing, flow dynamics, and mass and heat transfer in microreactors along with three strategies for scaling up microreactors: parallel numbering-up, consecutive numbering-up, and scale-out. We also propose a possible methodology to design microchemical systems. Finally, we provide a summary and future prospects.

Guangsheng Luo

Papers

Correlations of droplet formation in T-junction microfluidic devices: from squeezing to dripping

Preparation of highly monodisperse droplet in a T-junction microfluidic device

Shear force induced monodisperse droplet formation in a microfluidic device by controlling wetting properties

In situ preparation of magnetic chitosan/Fe3O4 composite nanoparticles in tiny pools of water-in-oil microemulsion

Design and Scaling Up of Microchemical Systems: A Review.