After two traditional manufacturing methods of key component——membrane electrode assemblies (MEA), the third generation ordered MEA has attracted great research interests in proton exchange membrane fuel cell. Ordered MEA could be divided into two kinds: MEA based on ordered proton transportation materials (e.g.nanowires, nanotubes, nanofibers of Nafion or other proton transportation materials) and MEA based on ordered electron transportation materials. However, ordered electron transportation MEA includes MEA based on ordered catalyst (e.g.Pt nanowires or other metal catalyst nanowires) and MEA based on ordered catalyst support such as carbon nanotube and carbon nanofibers. Electrode structure ordering is critical for decreasing Pt loading of the MEA, improving power performance and durability of fuel cell due to good multiphase mass transmission channels(e.g.proton, electron, gas and water transmission channels). Ordered MEAs and their manufacturing methods are reviwed in the paper based on the latest research literatures and patents recent years, and their characteristics and difference are analyzed in detail, which has guiding significance for high performance, low cost and longlife MEA.

Contents
1 Introduction
2 Previous attempts of the ordered MEA
2.1 Introduce of ordered catalyst support
2.2 Introduce of catalyst nanowire
2.3 Introduce of high proton transportation nanofiber
3 The third generation ordered MEA
3.1 MEA based on ordered catalyst support
3.2 MEA based on ordered catalyst
3.3 MEA based on ordered proton transportation materials
4 Conclusion and outlook

At present, carbonaceous materials are extensively adopted as an anode for commercial lithium-ion batteries. Zero-strain lithium titanate is generally considered as a more safe and long-life span anode compared with carbonaceous materials, and it will find specific applications in various fields such as hybrid electric vehicles, wind-light-electricity grids, and smart grids. However, the lithium-ion batteries using the lithium titanate as anode will easily swell during the charge-discharge cycle and storage, thus resulting in shell distortion, gas evolution, performance deterioration, and so on. This greatly prevents the practical application of lithium titanate.In this paper, the industrial developments of the four kinds of lithium-ion batteries using the lithium titanate anode are reviewed, and the associated cathode materials are Li (Ni_x Co_y Mn_1-x-y) O₂, LiMn₂O₄, LiFePO₄, and LiCoO₂, respectively. The latest research progress of the gas evolution mechanism is summarized from the perspectives of the interfacial characteristics, the water content, the electrolyte reductive decomposition, the negative electrode potential, and the impurities. At the same time, combined with the author's research work, the improving measures are put forward from the viewpoints of material, process, and application. Finally, the key issues and prospects of gassing are also commented.

Contents
1 Introduction
2 Industry status of lithium ion battery using lithium titanate as anode materials
3 Interface properties of lithium titanate material
4 The mechanism of gas evolution in lithium-ion batteries using an anode based on lithium titanate
4.1 Moisture
4.2 In the decomposition of electrolyte solution of lithium titanate electrode surface
4.3 Gas evolution reaction and the negative electrode potential
4.4 Impurities
5 Method to suppress gas evolution in lithium-ion batteries using an anode based on lithium titanate
5.1 Remove water or acid
5.2 Optimization of electrolyte
5.3 Surface treatment of lithium titanate material
5.4 Battery temperature and gas evolution
5.5 Optimization of lithium titanate battery manufacture process
6 Conclusion and outlook

As novel fluorescent nanomaterials, quantum dots (QDs) have played important roles in many fields, such as chemical analysis, biology sensor, molecular imaging, owing to their excellent optical properties. Studies on the properties of single quantum dots can help to find new experimental phenomenology which can't be found in the ensemble-approach, provide a mentality to improve the properties of quantum dots, contribute to a better application of quantum dots in various fields. In this review, identifications criterion of single quantum dots, photo-properties (such as fluorescence enhancement, bleaching, blinking, bluing, etc.) of single quantum dots, and quantum dots application (such as single quantum dots tracking, single quantum dots biosensor, super-localization technology) at single nanoparticle levels are commented. The challenges and existing problems of application of single quantum dots are summarized. In the future, synthesis in quantum dots should simultaneously satisfy many excellent photo-properties, including small size, high quantum yield, non-blinking, lager blue shift range, no-biotoxicty. Meanwhile, plasmonic quantum dots that not only exhibit strong fluorescence, but also become excellent probes for surface plasmon scattering, are another significant research field.

Contents
1 Introduction
2 Single molecule/nanoparticle detection
3 Photo-properties of single quantum dots
3.1 Fluorescence enhancement and bleaching
3.2 Blinking
3.3 Spectral blue shift
4 Application of quantum dots at single nanoparticle level
4.1 Single quantum dots tracking
4.2 Single quantum dots biosensor
4.3 Quantum dots in super-localization technology
4.4 Other application
5 Conclusion and outlook

Cyclic peptides are of considerable interest as potential protein ligands. Cell-permeable cyclic peptides receive much attention as peptide-based drugs owing to its cell permeability, specific targeting, and excellent stability in vivo. Nowadays, the researchers working on cell-permeable cyclic peptides focus on the issues as follow: new cell-permeable cyclic peptides from natural products and their structure-activity relationships, and the chemical modifications of cyclic or linear peptides to artificially obtain cell-permeable cyclic peptides. Here, we review the issues mentioned above. This article is arranged in two sections. The first section introduces two kinds of discovered natural products as cell-permeable cyclic peptides; the second section covers the strategies of modifying cyclic or linear peptides into cell-permeable cyclic peptides and the insight of the structure-activity relationship of cell-permeable cyclic peptides.

Contents
1 Introduction
2 Cell-permeable cyclic peptides from natural products
2.1 Cyclosporine A
2.2 Cyclotides
3 Cell-permeable cyclic peptides from artificial modification
3.1 Strategies of modification based on CSA
3.2 Strategies of modification based on cyclotides
3.3 Strategies of modification based on linear peptides
4 Conclusion

Conjugated polymers have received ever-increasing attention as fluorescent materials. They have many advantages compared with small-molecular fluorescent materials. As materials, conjugated polymers can be fabricated into different forms, such as thin films by spinning coating or drop casting, nano-/micro- fibers by electrospinning, nano-/micro- spheres, and micelle/vesicle/microtubule/nanoparticles by self-assembly. The great flexibility of conjugated polymers in processing makes it possible for them to meet the demands of different applications. With regard to the photophysics, the broader absorption allows conjugated polymers to be excited by different light sources. In addition, the high resistance to the photobleaching, or photostability, guarantees a long lifetime when conjugated polymers in real applications. These advantages allow conjugated polymers to be used in different fields, ranging from fluorescent bioimaging and sensors, to optical encoding and photoelectric displays. Some applications, such as encoding and display, require that the fluorescent materials have various emission colors. Thus fluorescent color tuning is very important and also very challenging for realization of these applications. This article gives some detailed discussion about the main mechanisms for the color tuning, based on the adjustment of the band gap of the single emission specie, or based on the chromaticity diagram advanced by International Commission on Illumination (CIE) for blending different emission species. The different methods for the color tuning are also discussed, such as physical blending of several emission species, copolymerization of different monomers, varying the substituent or the backbone of conjugated polymers, and changing the state of aggregation. Detailed examples with different chemical structures of polymers are provided to make clear illustrations about these mechanisms/methods.

Contents
1 Introduction
2 The mechanisms for fluorescent color tuning
3 Different methods for fluorescent color tuning of conjugated polymers
3.1 Physical blending
3.2 Copolymerization
3.3 Changing substituents
3.4 Controlling conjugated length
3.5 Varying the aggregations
4 Conclusion

Recently the crystallization-driven self-assembly of block copolymers into semicrystalline micelles in the selective solvent has been paid increasing attention due to the good controllability. In this paper we first review some factors controlling the morphology and size of the semicrystalline micelles of block copolymers, including solvent quality, structure of block copolymers, and crystallization temperature. The living growth of semicrystalline micelles with time and formation of "block co-micelles" using micelles as building blocks are also introduced. Finally, currently existing problems and outlook in this field are discussed.

Contents
1 Introduction
2 Morphologies of block copolymer crystalline micelles
2.1 Effect of chain structure of block copolymer
2.2 Effect of solvent quality
2.3 Effect of crystallization temperature
3 Living growth of block copolymer crystalline micelles
4 Block co-micelles
5 Conclusion and outlook

Chitosan is a biodegradable and biocompatible polymer with unique properties derived from marine resources, it is expected as important raw material for nanofibers with wide range of applications. Chitosan and its composite nanofibers have been fabricated by traditional spinning processes such like wet spinning or electrospinning, but these processes are complex, using harmful solvent or high voltage with lower safety. In search of more simple and safe nanofiber fabrication method applicable to chitosan, six kinds of novel nanofiber fabrication methods are reviewed, these methods are divided into two major categories of "small~large" approach and "large~small" approach. "Small~large" approach includes variety of spinning processes (such as rotary jet-spinning, handspinning and solution blowing) and two freeze casting processes (simple freeze-drying and jet-rapid freezing), while star burst system as an example of "large~small" approach. Both advantages and disadvantages of each method are compared from the viewpoint of fiber diameter, fiber orientation and the applicability to chitosan. A new innovative idea of combining ultrasonic atomization and freeze casting process for chitosan nanofibers is also provided in this review. Ultrasonic atomization combined with freeze casting method is simple and avoids usage of volatile solvents. Chitosan nanofibers obtained by this innovative method could be applicable to biomedical engineering and food engineering due to both chitosan's characteristics and the safety of fabrication process.

Contents
1 Introduction
2 Spinning nanofiber fabrication methods
2.1 Rotary jet-spinning
2.2 Handspinning
2.3 Solution blowing
3 Freeze casting nanofiber fabrication methods
3.1 Simple freeze-drying
3.2 Jet-rapid freezing
4 Star burst nanofiber fabrication method
5 Conclusion and outlook

The freeze-drying technique is an attractive method because it is an environmental friendly and cost-effective shaping process for preparing advanced materials with interconnecting pore channels or pore gradients in bodies. Freeze-drying technology is a kind of methods to build porous structural material efficiently and controllably. In recent years many new polymer-based materials prepared by freeze-drying have exhibited broad applications as functional materials. This article reviews the progress of advanced polymer materials prepared by freeze-drying, and summerizes the applications in the field of materials engineering, environment, biomedicine and other prospects. The research prospects and directions of this rapidly developing field are also briefly addressed.

Contents
1 Introduction
2 The fabrication of polymer-based materials by direct freeze-drying
2.1 Solution freeze-drying
2.2 Emulsion freeze-drying
3 The fabrication of polymer-based materials by indirect freeze-drying
4 Applications of polymer-based materials prepared by freeze-drying
4.1 The application in tissue engineering and medicine
4.2 The application in the fields of adsorption and separation
4.3 The application in conduct electricity and gas detection
5 Conclusion

Duplex-specific nuclease (DSN) is a type of nuclease, that is isolated from the hepatopancreas of the Kamchatka crab. DSN displays a strong preference for cleaving double-stranded DNA or DNA in DNA-RNA heteroduplexes, and is practically inactive toward single-stranded DNA or RNA. Moreover, this enzyme shows excellent discrimination capability between perfectly and imperfectly matched (up to one mismatch) short duplexes. Owing to its unique feature of cleaving DNA, DSN enzyme is widely applied in the fields of biomedicine and molecular biology, including full-length cDNA library normalization,genomic single-nucleotide polymorphism (SNP) detection and high throughput sequencing. The recent research on DSN are mainly focused on the applications in microRNAs (miRNAs) detection using a DSN-mediated signal amplification strategy. miRNAs are a group of short, endogenous, noncoding RNAs that play vital regulatory roles in physiologic and pathologic processes, including hematopoietic differentiation, cell cycle, regulation, and metabolism. So miRNA is one of the most important biomarkers in individualized treatment, which has great value in terms of improving the diagnosis and treatment of diseases. However, detection of miRNAs is challenging owing to their unique characteristics, including a small size, sequence homology among family members, low abundance in total RNA samples, and susceptibility to degradation in solution. In recent years, isothermal signal amplification and detection of trace miRNA in fluids are reported by many researchers using DSN-mediated biosensors. According to different detection principle of biosensors, DSN-mediated biosensors can be classified as colorimetric, fluorescent, and electrochemical. In this review, we intensively summarize the advantages of DSN in miRNAs detection using DSN-based signal amplification strategy, expanded applications in SNP detection, high throughput sequencing and cDNA library normalization especially when being combined with SMART (Switching Mechanism At 5'end of RNA Transcript) technique.

Contents
1 Introduction
2 The application of DSN enzyme in microRNA detection
2.1 Colorimetric analyses
2.2 Fluorescent analyses
2.3 Electrochemical analyses
3 The application of DSN enzyme in SNP detection
4 Other biological applications of DSN enzyme
4.1 Construction of cDNA Library
4.2 High throughput sequencing
5 Conclusion and outlook

Surface engineering of biomedical nanoparticles is of great importance to maintain nano-stability, resist nonspecific biomolecular adsorption so as to enhance in vivo circulation time. Cell membrane mimicking zwitterions can form superhydrophilic antifouling surface which helps to maintain colloidal stability and resist immune elimination via electrostatically induced hydration. The stealthy surface prolongs the blood circulation time to reach "passive targeting", further "active targeting" is also available if combined with stimuli-responsive or bioactive molecules. Hence "zwitteration" has been developed as a new surface engineering strategy of biomedical nanoparticles. This review mainly talks about surface engineering of inorganic nanoparticles with small molecular and polymeric zwitterions, zwitterionic polymeric assemblies as drug delivery system and zwitterionic polymeric prodrugs. Introduction of special properities and applications of mixed-charge materials is also involved.

Contents
1 Introduction
2 Surface design of inorganic nanoparticles with zwitterions
2.1 Small molecular zwitterions
2.2 Polymeric zwitterions
3 Zwitterionic polymeric assemblies for drug delivery
3.1 Drug non-covalently loaded assemblies
3.2 Polymeric prodrugs
4 Mixed-charged materials
5 Conclusion and outlook

Extracellular electron transfer (EET) between electrochemically active microorganisms and electrodes plays a key role in microbial electrochemical systems (MESs) functioning of energy generation, bioremediation, etc. At present, researchers have a very limited understanding of the mechanism of EET, which is one of the major bottlenecks in application of MESs. Compared with direct electron transfer which requires a direct contact between microbial functional proteins and electrode, mediated electron transfer use electron transfer mediators (ETMs) which have reversible redox activities accompanies by high-efficiency EET for transporting electrons. ETMs serve as the middle electron acceptor, once reduced, can transfer electrons to terminal electron acceptor where upon it becomes re-oxidized. In principle, ETMs molecules could cycle thousands of times,thus, have a significant effect on the turnover of the terminal oxidant (e.g.iron) in certain circumstances.This review summarizes the recent advances of EET mechanisms with focus on mediated EET in MESs. Furthermore, we have highlighted the research trends of ETMs in MES,which will promote the practical applications of MESs in bioremediation, energy generation and so on.

Contents
1 Introduction
2 Roles of electron transfer mediators in extracellular electron transfer
3 Properties of electron transfer mediators
4 Classification of electron transfer mediators
5 Electron transfer mediators and their electron transfer mechanism
5.1 Exogenous electron transfer mediators
5.2 Endogenous electron transfer mediators
6 Outlook

Photoresist is the indispensable and key material used for fabricating large-scale and super-large-scale integrated circuits in microelectronic industry. Due to its strategic role in the construction of national economy and national defense, photoresist has aroused great attention of researchers. Since the birth of the first integrated circuit board in 1959, photoresist has gradually evolved from the resists used for traditional ultraviolet (UV) photolithography, including early polyvinyl cinnamate, cyclized rubber/azide system, near-UV (436-nm G-line and 365-nm I-line) novolac/diazonaphthoquinone photoresists, deep-UV (DUV, 248-nm and 193-nm) and vacuum-UV (157-nm) photoresists, to the resists used for the so-called next generation lithography (NGL), such as extreme-UV lithography (EUVL), electron-beam lithography (EBL), nanoimprint lithography (NIL), block copolymer lithography (BCL), and scanning probe lithography (SPL). In this review, the above evolution of photoresist and its research progress are summarized based on a large amount of literature. Thereinto, DUV chemically amplified photoresists are focused, including matrix resins, photoacid generators, and additives (for example, dissolution inhibitors and basic compounds). In addition, the recent research achievements of the resists for EUVL, EBL, NIL, BCL, and SPL are also highlighted. Finally, the prospect and research directions of photoresist in the future are briefly discussed.

Contents
1 Introduction
2 Polyvinyl cinnamate and cyclized rubber negative-tone photoresists
3 G-line and I-line photoresists
3.1 Novolac/diazonaphthoquinone (DNQ) resists
3.2 Other systems
4 Deep-ultraviolet (DUV) photoresists
4.1 248-nm photoresists
4.2 193-nm photoresists
5 Vacuum-ultraviolet (157-nm) photoresists
6 Resists for next generation lithography (NGL)
6.1 Extreme-ultraviolet lithography (EUVL)
6.2 Electron-beam lithography (EBL)
6.3 Nanoimprint lithography (NIL)
6.4 Block copolymer lithography (BCL)
6.5 Scanning probe lithography (SPL)
7 Conclusions and perspective