Organic photodiodes (OPDs) have attracted great attention for potential applications in organic optocouplers, image sensors, immune detection and optical communication, due to their advantages of low cost, plenty of functional materials, tunable absorption wavelengths and compatibility with flexible substrates. This article presents an overview of organic photosensitive materials widely used in OPDs, with response spectra regioning from UV to near infra-red. Researches on structure optimization, interface modification, carriers transmission mechanism and internal optical distribution of OPDs are summarized. Some practical applications of the OPDs in optoelectronic fields are also introduced. Finally, an outlook on future development of OPDs is briefly brought up.

Contents
1 Introduction
2 The progress of materials on organic photodiodes
2.1 The materials used in organic photodiodes for visible light
2.2 The materials used in organic photodiodes for UV light
2.3 The materials used in organic photodiodes for near infra-red light
3 The structural optimization and interface modification for the organic photodiodes
3.1 The organic photodiodes with planar heterojunction structure
3.2 The organic photodiodes with bulk heterojunction structure
3.3 The organic photodiodes with other structure
3.4 The research of interface mechanism in organic photodiodes
3.5 The calculation of optical distribution in organic photodiodes
3.6 The stability of organic photodiodes
4 Outlook on future development of organic photodiodes

Mechanically interlocked rotaxane molecular shuttles occupy an important position in the area of molecular machines chemistry, and is a good "bottom-up" strategy for the self-assembly of new materials at the molecular level. In such shuttles, a macrocycle can be translocated between different "stations" or recognition sites of the thread in response to an external stimulus. The alternation of relative positions of the interlocked components can result in varying physical or chemical properties. The alternative variation of properties constitutes a basic kind of mechanical switch, capable of performing particular functions. The above-mentioned molecular shuttles have attracted wide attentions of supramolecular chemists due to their potential applications as molecular devices for switches, information storage and processing, and so on. In this paper, the new research progress in chemically driven [2]rotaxane molecular shuttles on syntheses and applications in recent years is reviewed, based on the driving forces (i.e. external stimuli) such as acid/base driven, ion coordination interaction driven, hydrophobic interaction driven induced by the change of solvent polarity. And the other forces driven [2]rotaxane molecular shuttles are also summarized such as thermodynamical entropy, the size of the decorated groups in the interlocked system, chemical oxidants or reductants, electrochemical redox related to electron gain or loss, photoisomerization of the azobenzene unit between trans and cis isomer induced by UV or visible light irradiation, and so on. Furthermore, the future development of such [2]rotaxane molecular shuttles is prospected.

Contents
1 Introduction
2 Chemically driven [2]rotaxane molecular shuttles
2.1 Acid/base driven [2]rotaxane molecular shuttles
2.2 Ion coordination interaction driven [2]rotaxane molecular shuttles
2.3 Hydrophobic interaction driven induced by the change of solvent polarity [2]rotaxane molecular shuttles
2.4 Other forces driven [2]rotaxane molecular shuttles
3 Conclusion and outlook

Li₄Ti₅O₁₂ has the advantages of resource, performance, and so on. Recently, Li₄Ti₅O₁₂ anode material is becoming an important research direction in the field of energy storage and power battery. In this review, the effects of doping ions with the different doping sites in the crystal lattice and its intrinsic properties on the structure and performance of Li₄Ti₅O₁₂ were discussed. Substitution of doping ions for Li ions on the tetrahedral 8a sites would lower the Li-ion conductivity. Substitution of doping ions for Li ions on the octahedral 16d sites may "correct" distribution of alkali metal ions. Substitution of doping ions for Ti ions on the octahedral 16d sites would affect structural stability of Li₄Ti₅O₁₂. Substitution of doping ions for O ions on the octahedral 32e sites would affect the conductivity. In certain conditions, if the valence state of doping ions is higher than the substituted ions, the electronic conductivity of Li₄Ti₅O₁₂ could be improved. Doping elements with different energy band structures and redox behaviors affect the electrochemical reaction process of Li₄Ti₅O₁₂. The different ionic radius and the number allowed to enter the lattice of doping ions would change the Li₄Ti₅O₁₂ lattice constant and microstructure morphology.

Contents
1 Introduction
2 Structure properties of Li₄Ti₅O₁₂
3 Doping of Li₄Ti₅O₁₂
3.1 Position of dopants
3.2 Properties of dopants
3.3 Atmosphere of doping
4 Latest developments
5 Conclusion and outlook

Carbon materials with multi-modal pore structures can integrate advantages of mciro-, meso- and/or macropores in mass transfer, besides their large specific surface area, large pore volume, excellent chemical stability and good electron conductivity. They are highly promising in applications such as electrochemical capacity, drug delivery, catalysis, adsorption, and separation due to these outstanding properties. Solid materials with different macrostructures including stacked silica and organic microspheres are often used as hard templates for synthesizing hierarchically porous carbon with various pore shapes and pore sizes. Besides these templates, commercial polyurethane foam with a tri-dimensionally interconnected cellular network, controllable porosity, and easy removal make it a competitive candidate as a skeleton template. It have been used as a sacrificial matrix for fabricating hierarchically porous materials including silica, ceramic, biological scaffold, nanocrystalline metal oxide, metal foam and nanocomposite. In this review, we present recent development in the fabrication and application of hierarchically porous carbons templated from polyurethane foam. The obtained carbons with monomodal or bimodal pore structure, which were prepared by introducing microporous or mesostructured template additionally, are cautiously classified for discussion in details. Their unique performances in applications of energy storage, catalysis reaction and large molecule separation are also briefly mentioned. Challenges in adjusting the ratio of pores in three scales, graphitizing, and enhancing the mechanical strengthen of carbons are still remained for further development. Some strategies aiming to the problems are also proposed.

Contents
1 Introduction
2 Preparation of hierarchically porous carbon materials using polyurethane foam as a template
2.1 Macroporous carbon
2.2 Macro-mesoporous carbon
2.3 Micro-mesoporous carbon
2.4 Macro-microporous carbon
3 Conclusion

Silver nanoparticles have been the focus of research in recent decades because of their distinct physical, chemical, and biological properties. The application properties of silver nanoparticles are influenced not only by their size, size distribution and purity but also the shape. The differently shaped silver nanoparticles have strong effects on its antibacterial properties, optical properties and the comprehensive performance of silver polymeric nanocomposites. More potential properties of silver polymeric nanocomposites will be achieved by shape control synthesis of silver particles. Thus, the development and improvement of the synthetic methods and the research of the mechanism of shape control of silver nanoparticles have become more and more important. In this paper, recent progress in synthetic methods of silver nanoparticles and different shapes of silver nanoparticles is reviewed. Radiolytic methods, laser ablation methods, electrochemical methods, photochemical methods and biosynthesis of silver nanoparticles have been discussed. Their advantages and disadvantages are highlighted. The mechanism of shape control, including template-directed methods, thermodynamic control, kinetic control and oxidative etching is presented. The development of silver polymeric nanocomposites has been introduced.

Contents
1 Introduction
2 Shape control synthesis of silver nanoparticles
2.1 Synthetic methods
2.2 Shape control mechanism
2.3 Different shapes of Ag NPs
3 Silver polymeric nanocomposites
3.1 Engineering polymers
3.2 Conductive polymers
3.3 Biopolymers
3.4 Amphiphilic polymers
3.5 Liquid crystalline polymers
3.6 Natural polymers
4 Conclusion and outlook

Due to the great importance of chiral compounds in the manufacture of drugs, vitamins, fragrances, and optical materials, the synthesis of chiral building blocks has attracted special attention. Chiral epoxides are among the most important intermediates that can react with a variety of reagents because of the polarity and ring-strain of the epoxide ring. Asymmetric epoxidation of olefins can convert prochiral olefins into epoxides with chiral carbon, which can be readily converted into various chiral compounds via regioselective ring-opening or functional group transformation reactions. Asymmetric synthesis reactions have been mainly induced by substrates or catalysts. The asymmetric synthesis induced by chiral catalysts is one of the most attractive and competitive areas in modern organic synthesis, because it can get a lot of new optical active substances using catalytic amount of chiral compounds. Asymmetric catalytic epoxidation of unfunctionalized olefins induced by the chiral catalyst has been the most effective way to obtain optical pure chiral epoxides. These chiral catalysts include enzymes, metal porphyrins, Salen-Mn (Ⅲ) complexs and organocatalysts. Among them, the synthesis of metal porphyrins and Salen-Mn (Ⅲ) complexs is inspired by enzymes. The organcatalyst, which does not contain metal ions, is regarded as a low pollution and lower toxicity catalyst. Asymmetric epoxidation of olefins catalyzed by these catalysts can get satisfactory yield and enantiomeric selectivity. Recent progress of enzymes, metal porphyrins, Salen-Mn (Ⅲ) complexs, and organcatalysts used for asymmetric epoxidation of olefins is reviewed. Moreover, the catalytic mechanisms and the development trend of this reaction are discussed.

Contents
1 Introduction
2 Enzyme-catalyzed asymmetric olefin epoxidation
2.1 Monooxygenases
2.2 Peroxidases
2.3 Artificial metalloenzymes
3 Metal porphyrin-catalyzed asymmetric epoxidation of unfunctionalized olefins
4 Salen-Mn (Ⅲ) complex-catalyzed asymmetric epoxidation of unfunctionalized olefins
4.1 Unsupported Salen-Mn(Ⅲ) complex-catalyzed asymmetric epoxidation of unfunctionalized olefins
4.2 Supported Salen-Mn(Ⅲ) complex-catalyzed asymmetric epoxidation of unfunctionalized olefins
4.3 Application of ionic liquid in Salen-Mn (Ⅲ) complex-catalyzed olefin asymmetric epoxidation
4.4 The mechanism of olefin asymmetric epoxidation catalyzed by Salen-Mn(Ⅲ) catalysts
5 Organic small molecule-catalyzed olefin asymmetric epoxidation
5.1 Chiral ketone-catalyzed olefin asymmetric epoxidation
5.2 Chiral iminium-catalyzed olefin asymmetric epoxidation

Conducting polymers (CPs) are conjugated polymers with interesting chemical and physical properties. CP-based drug delivery systems (DDSs) have been developed rapidly in the past few decades. The advantages of CPs as potential candidates for application in DDSs are derived from their inherent electroactivity, ease of preparation and applicability to a wide spectrum of dopants, including anionic, cationic and neutral biomolecules. More importantly, due to the switching property of the redox states external electrical stimulations can be used to alter the electronegativity, conductivity, doping level and volume of CPs. Moreover, the structure and surface morphology of CPs can be tailored by incorporating different dopants or carbon nanotubes (CNTs) as well as by different preparation methods. Capitalizing the unique properties, CP-based DDSs can provide high drug load, trigger release of the incorporated drugs, control drug release and modify the release rate of the drugs. In this review, we briefly introduce the properties and preparation methods of CPs, and summarize the research progress of drug loading and release of CP-based DDSs. Finally, potential problems, challenges and future development in this area are proposed and discussed.

Contents
1 Introduction
2 The properties and preparation of conducting polymers
3 Drug incorporation and release of conducting polymer-based drug delivery system
3.1 Drug incorporation
3.2 Drug release
4 The modification of conducting polymer-based drug delivery system
4.1 Nano modification
4.2 Conducting hydrogel
4.3 Biotin-doped modification
4.4 Bilayer system
4.5 Self-powered system
4.6 Fluorescence imaging system
5 Challenges and future directions

DNA methylation, which refers to methyltransferases (MTases)-catalyzed covalent addition of a methyl group to adenine or cytosine residues in the specific DNA sequence, is one of the hottest research areas on epigenetic modification of genomic DNA. According to numerous studies, DNA methylation may cause the change of DNA structure, stability and interaction mode between DNA and protein, thus affecting gene expression, which may lead to many neurodegenerative diseases, immune system diseases and even cancer. Therefore, development of sensitive, selective, simple, and economical methods for DNA methylation determination is highly required. With increasing progress in the methylation studies, a series of detecting techniques has been developed to match various requirements of methylation studies. All of these study methods can be divided into four groups: genome-wide methylation extent analysis, gene-specific methylation analysis, methylation transferase activity analysis and new methylated sites screening. Among these methods, electrochemical techniques have been widely used for DNA methylation determination and MTases activity. Here we briefly review the detection of DNA methylation. Then more detail in the work on the electrochemical method are described, including direct electrochemical analysis methods, indirect electrochemical analysis methods, electrogenerated chemiluminescence methods and photoelectrochemical methods. In the end, the prospects of DNA methylation analysis are introduced.

Contents
1 Introduction
2 Analysis methods for DNA methylation
3 Electrochemical analysis methods for DNA methylation
3.1 Direct electrochemical analysis methods for DNA methylation
3.2 Indirect electrochemical analysis methods for DNA methylation
3.3 Electrogenerated chemiluminescence methods for analysis of DNA methylation
3.4 Photoelectrochemical methods for analysis of DNA methylation
4 Conclusion

The telomerase ribonucleoprotein is a reverse transcriptase that plays a critical role in the maintenance of telomere length by synthesizing telomeric DNA repeats using its instinct RNA as the template and thus protects chromosome ends from degradation and fusion. Most normal somatic cells do not express detectable telomerase activity and telomeres shorten progressively with each cell division, while in almost all kinds of cancer cells human telomerase exhibits high activity, suggesting that there is a direct association between telomerase activity and various diseases including cancer and age-related diseases, and that telomerase could be used both as a diagnostic biomarker for the early detection of human cancer and as a potential target for anti-cancer therapy. However, fully understanding the biochemical action of human telomerase is presently a huge challenge since it is a very big complex. Moreover, it is remarkably difficult to get enough amount of heloenzyme for traditional enzyme analysis. Novel and advanced methods therefore should be employed to assay human telomerase and understand enzymatication. Single molecule techniques such as single-molecule fluorescence resonance energy transfer (smFRET) technique and two-color coincidence detection (TCCD) not only can detect dynamic of individual molecule and flexibility of enzyme catalysis, but also can check very little amount of samples in solution or on surface, which can not be performed by bulk experiment. In this review, we summarize the progress and prospect of telomerase research and describe several latest single-molecule methods applied to assaying telomerase structure, function, activity and dynamics.

Contents
1 Introduction
2 Single molecule fluorescence technique
2.1 Development of single molecule fluorescence techniques
2.2 Classification of single molecule fluorescence techniques
2.3 Common single molecule fluorescence techniques
3 Telomere, telomerase and cancer
3.1 Structure and function of telomere and telomerase
3.2 Relationship between telomere, telomerase and cancer
3.3 Telomerase as a diagnostic biomarker and therapeutic target for cancer
4 Single molecule fluorescence studies of human telomerase
4.1 Common methods for telomerase detection
4.2 Single molecule fluorescence techniques applied to telomerase detection
5 Conclusion

Lignin is the component with the highest carbon content in biomass. The transformation of lignin to high-grade liquid fuels can be achieved via hydrodeoxygenation(HDO) of phenolic intermediates derived from the products of lignin depolymerization. The octane numbers of the hydrodeoxygenation products of phenolic intermediates are quite high. They have vapor pressures and carbon atom number (C6~C10) within the range of gasoline. Thus, these hydrodeoxygenation products would be the most desirable components for a fungible liquid transportation fuel. This is very meaningful to application of lignin. Recently, researches about the hydrodeoxygenation of phenolic compounds develop rapidly. In this paper, the HDO reactions of phenolic compounds using sulfided Mo-based catalyst, noble metal catalyst and inexpensive non-sulfided catalyst are reviewed in detail. It is found that most of the investigated catalysts are bifunctional catalysts, combining the hydrogenation function of active metal with hydrolysis and dehydration of support. The catalytic mechanism for the HDO of phenolic compounds is sketched, and the effects of catalyst supporter on the catalytic activity are also discussed. Furthermore, the current technique challenges are summarized, and future technologic explorations for the efficient hydrodeoxygenation of lignin-derived phenolic compounds are proposed.

Contents
1 Introduction
2 Sulfided Mo-based catalysts
3 Noble catalysts
4 Inexpensive non-sulfided catalysts
5 Effects of supports
6 Conclusions and outlook

Reverse osmosis (RO) and nanofiltration (NF) are widely used in many water treatment processes, such as seawater and brackish water desalination. Membranes with improved separation performance and anti-fouling properties can be prepared by incorporating nanoparticles into membrane matrix. A number of nanomaterials can serve as potential water transport channels and modify the structure and surface properties of the membrane thin film layers. Mixed-matrix membranes (MMMs) can benefit from the high performance of both the organic matrix and inorganic fillers, which are believed to be the next generation of novel membrane materials. Recent advances of the nanoparticle-filled RO, NF and forward osmosis (FO) MMMs are reviewed in this paper. The effects of nanomaterials with various properties on membrane structure and separation performance are discussed, including zeolites, nanotubes, mesoporous materials, pure metal, metallic oxides, graphene oxide and aquaporin. The dispersibility of nanofillers in MMMs and their compatibility with polymer matrix can be improved by surface modification. Different methods of nanoparticle addition and membrane preparation are also illustrated in detail. Based on the analysis of the recent works, the membrane formation and separation mechanisms are explored and the main problems of membrane synthesis and application are summarized. Finally, the future development of RO, NF and FO MMMs for water treatment process is suggested.

Contents
1 Introduction
2 Mixed-matrix reverse osmosis membranes
2.1 Different types of nanomaterials
2.2 Modification of nanomaterials
2.3 Adding methods of nanomaterials
3 Mixed-matrix nanofiltration membranes
3.1 Interfacial polymerization
3.2 Phase inversion
4 Mixed-matrix forward osmosis membranes
5 Conclusion and outlook

Asymmetric nanomaterials (Janus nanomaterials) comprising at least two components of different chemistry, functionality, and/or polarity have attracted great scientific interest in a wide range of applications. Additional properties are attributed to the asymmetric spatial distribution of functionalities on a single anisotropic nanoparticle, like amphiphilicity or new catalytic characteristic. In addition, Janus nanomaterials' synergistic potential for multilevel targeting, and combination therapies make them particularly attractive for biomedical applications including biosensing, targeting delivery and bio-detection. In this paper, the advances in properties and applications of Janus nanomaterials are summarized. First, some properties and applications of Janus nanomaterials are described in three different aspects: amphipathicity, catalytic characteristic and biocompatibility. Second, the main biomedical applications are highlighted, which include biosensing, targeting delivery, gene vaccine and antimicrobial. Finally, the further development in preparation of Janus nanomaterials and their applications in food safety are expected.

Contents
1 Introduction
2 Properties of Janus particles
2.1 Amphipathy
2.2 Catalytic characteristic
2.3 Biocompatibility
3 Construction and applications of bioprobes based on Janus particles
3.1 Biological sensing
3.2 Targeting delivery
3.3 Gene vaccine
3.4 Antibacterial agents
4 Outlook