Metal cyanamides: Open-framework structure and energy conversion/storage applications

Metal cyanamides are an emerging class of functional materials with potential applications in sustainable energy conversion and storage technologies such as catalysis,supercapacitors,photoluminescence and next-gen batteries.The[NCN]^(2-)as the anion,which is isolobal with[O]^(2-)endows metal cyanamides with similar physicochemical properties as oxides and chalcogenides.Whereas the unique quasI-linear structure and electronic resonance between[N=C=N]^(2-)and[N-C≡N]^(2-)of[NCN]entity bring out superior properties beyond oxides and chalcogenides.In this review,we present research status,challenges,and the recent striking progress on the metal cyanamides in the synthesis and applications.Specifically,the characteristic structures,physicochemical properties,synthetic methods with corresponding merits/demerits and latest applications in energy conversion and storage of cyanamides are summarized.The detailed outlooks for the new compounds design,morphology manipulation and potential applications are also exhibited.

In-Plane and Out-of-Plane Mechanical Properties of Zero Poisson’s Ratio Cellular Structures for Morphing Application

Intelligent structures like zero Poisson’s ratio(ZPR)cellular structures have been widely applied to the engineering fields such as morphing wings in recent decades,owing to their outstanding characteristics including light weight and low effective modulus. In-plane and out-of-plane mechanical properties of ZPR cellular structures are investigated in this paper. A theoretical method for calculating in-plane tensile modulus,in-plane shear modulus and out-of-plane bending modulus of ZPR cellular structures is proposed,and the impacts of the unit cell geometrical configurations on in-plane tensile modulus,in-plane shear modulus and out-of-plane bending modulus are studied systematically based on finite element(FE)simulation. Experimental tests validate the feasibility and effectiveness of the theoretical and FE analysis. And the results show that the in-plane and out-of-plane mechanical properties of ZPR cellular structures can be manipulated by designing cell geometrical parameters.

Development and prospects of degradable magnesium alloys for structural and functional applications in the fields of environment and energy

Magnesium and its alloys have such advantages with lightweight, high specific strength, good damping, high castability and machinability,which make them an attractive choice for applications where weight reduction is important, such as in the aerospace and automotive industries.However, their practical applications are still limited because of their poor corrosion resistance, low high temperature strength and ambient formability. Based on such their property shortcomings, recently degradable magnesium alloys were developed for broadening their potential applications. Considering the degradable Mg alloys for medical applications were well reviewed, the present review put an emphasis on such degradable magnesium alloys for structural and functional applications, especially the applications in the environmental and energy fields. Their applications as fracture ball in fossil energy, sacrificial anode, washing ball, and as battery anodes, transient electronics, were summarized. The roles of alloying elements in magnesium and the design concept of such degradable magnesium alloys were discussed. The existing challenges for extending their future applications are explored.

Sialon 陶瓷材料的结构、性质及应用

系统地评述了不同种类单相Sialon陶瓷的结构特征和物理、化学性质 ,并介绍了Sialon在冶金工业等方面的应用。单相Sialon陶瓷中 ,β’ Sialon强度和韧性最高 ,α’ Sialon硬度和耐磨性最好 ,O’ Sialon抗氧化性最佳。

复相Sialon陶瓷材料的研究进展

复相 Sialon 陶瓷材料是一种比单相 Sialon 性能更优良的高技术新材料。较详尽地阐述了目前已制备出的各种复相 Sialon 陶瓷材料的性能,特别报道了目前研究较少的 O′-Sialon-TiN 复相陶瓷材料的部分性能,并展望了复相 Sialon 陶瓷材料的应用前景。

Properties and Applications of Bamboo Fiber—A Current-State-of-the Art

Fibers are used in many forms in engineering applications–one of the most common being used as reinforcement.Due to its renewable short natural growth cycle and abundance of bamboo resources,bamboo fiber has attracted attention over other natural fibers.Bamboo fiber has a complex natural structure but offers excellent mechanical properties,which are utilized in the textile,papermaking,construction,and composites industry.However,bam-boo fibers can easily absorb moisture and are prone to corrosion limiting their use in engineering applications.Therefore,a better understanding of bamboo fiber is particularly important.This paper reviews all existing research on the mechanical characterization of bamboo fiber with an emphasis on the extraction and treatment techniques,and their effect on relevant properties.The chemical composition of bamboo fibers has also been thoroughly investigated and presented herein.Current applications and future opportunities for bamboo fibers in various fields have been presented with a focus on research needs.This work can serve as a reference for future research on bamboo fiber.

Sialon基陶瓷的结构特征及物理和化学性质

全面地评述了Sialon基各单相、复相陶瓷的结构特征及物理和化学性质，并从结构角度对各Sialon基陶瓷的性质进行了解释。单相Sialon陶瓷中，β-Sialon强度和韧性最高，a’－Sialon硬度和耐磨性最好，O’－Sialon抗氧化性最佳。目前Sialon陶瓷正朝着复相化的方向发展，开发出了许多综合性性优良的复相Sialon陶瓷。基于Si－AlO－N系相平衡制备的。a＋β’）-、（β’＋AlN多型体）-、（O‘＋β’）一复相Sialon陶瓷实现了各组成相在结构和性能上的优势互补与叠加。通过外加第二相，利用晶须（或纤维）补强、相变增韧、颗粒弥散强化等原理制得的复相Sialon陶瓷如SiCw／f／Sialon、ZrO2／Sialon、SiC／Sialon、BN／Sialon等都取得了显著的增强增韧效果。

Recent progress in molten salt synthesis of low-dimensional perovskite oxide nanostructures, structural characterization,properties, and functional applications: A review

Molten salt synthesis （MSS） method has advantages of the simplicity in the process equipment, versatile and large-scale synthesis, and friendly environment, which provides an excellent approach to synthesize high pure oxide powders with controllable compositions and morphologies. Among these oxides, perovskite oxides with a composition of ABO3 exhibit a broad spectrum of physical properties and functions （e.g. ferroelectric, piezoelectric, magnetic, photovoltaic and photocatalytic properties）. The downscaling of the spatial geometry of perovskite oxides into nanometers result in novel properties that are different from the bulk and film counterparts. Recent interest in nanoscience and nanotechnology has led to great efforts focusing on the synthesis of low-dimensional perovskite oxide nanostructures （PONs） to better understand their novel physical properties at nanoscale. Therefore, the low-dimensional PONs such as perovskite nanoparticles, nanowires, nanorods, nanotubes, nanofibers, nanobelts, and two dimensional oxide nanostructures, play an important role in developing the next generation of oxide electronics. In the past few years, much effort has been made on the synthesis of PONs by MSS method and their structural characterizations. The functional applications of PONs are also explored in the fields of storage memory, energy harvesting, and solar energy conversion. This review summarizes the recent progress in the synthesis of low-dimensional PONs by MSS method and its modified ways. Their structural char- acterization and physical properties are also scrutinized. The potential applications of low-dimensional PONs in different fields such as data memory and storage, energy harvesting, solar energy conversion, are highlighted. Perspectives concerning the future research trends and challenges of low-dimensional PONs are also outlined. ~ 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

Nonlinear optical and optical limiting properties of new structures of organic nonlinear optical materials for photonic applications

The nonlinear optical （NLO） and optical limiting （OL） properties of three new structures of organic NLO guest host Poly（N-vinylcarbozole）/disperse orange 3 （PVK/DO3）, PVK/disperse orange 13 （PVK/DO13）. and PVK/disperse orange 25 （PVK/DO25） as a solution at different concentrations and as a thin-film sample are studied using continuous wave z-scan system at 532 nm. The open-aperture z-scan data of the NLO materials in the solution and thin-film samples displayed two-photon and saturable absorptions, respectively. The PVK/DO13 exhibites the largest and best values of the nonlinearities, such as n2, β, X（3） compared with those of PVK/DO3 and PVK/DO25. This nonlinearity increases as the concentration increases. Tile results indicate that these NLO materials are good candidates for optical switching and OL devices.

Preparation, structure, properties, and application of copper nitride (Cu_3N) thin films: A review

Copper nitride（Cu3 N） thin films display typical trans-rhenium trioxide structures. They exhibit excellent physical properties, low cost, nontoxicity, and high stability under room temperature. However, they possess low-thermal decomposition temperature, and their lattice constant often changes significantly with prepared technologies or techniques, thereby enabling the transformation from insulators to semiconductors and even conductors. Moreover, Cu3 N thin films are becoming the new research hotspot of optical information storage devices, microelectronic semiconductor materials, and new energy materials. In this study, existing major prepared technologies of Cu3 N thin films are summarized. Influences of prepared technologies of Cu3 N thin films on crystal structure of films, as well as influences of prepared conditions and methods（e.g., nitrogen pressure, deposition power, substrate temperature, and element addition） on crystal structure and optical, electrical, and thermal properties of films were analyzed. The relationship between crystal structure and physical properties of Cu3 N thin films was explored. Finally,applications of Cu3 N thin films in photoelectricity, energy sources, nanometer devices, and other fields were discussed.

Atomically precise copper nanoclusters as ultrasmall molecular aggregates:Appealing compositions,structures,properties,and applications

Metal nanoclusters(NCs)are ultrasmall molecular aggregates consisting of dozens to hundreds of metal atoms consolidated by organic ligands,which represent an emerging area of nanoscience.Amide a myriad of metal NCs,copper NCs(CuNCs)comprise a low-cost,high-value subclass that has attracted great attention.The variable copper cores and diversity of protecting ligands have rendered CuNCs interesting molecular aggregates featuring structural and compositional versatility,hence showing distinctive properties and potential applications.In the present review,we have summarized the progress on atomically precise CuNCs that exhibit a range of appealing properties and applications in different fields.This review is expected to provide not only an overview of the current development on atomically precise CuNCs,but also possible directions for the future design of novel CuNCs for fundamental studies and practical applications.

Mechanical properties of coppiced and non-coppiced Pterocarpus erinaceus boles and their industrial application

Rosewood(Pterocarpus erinaceus Poir.)is valued for flooring,ornaments,musical instruments and furniture-making due to its durability,strength,beauty and acoustic properties.It coppices easily which could boost its continual supply.Compression parallel to grain,Modulus of Elasticity(MOE)and Modulus of Rupture(MOR)within coppiced and non-coppiced boles were determined.These properties decreased along both types of boles.Strength values for the heartwood were also greater than those for the sapwood of each type of bole.MOE,MOR and compression for non-coppiced stems were greater than those from the coppiced stems.The differences were significant(p<0.05).Mechanical properties from the coppiced and non-coppiced boles are comparable.Both have strength properties comparable with those of species widely used for railway sleepers,structural supports,flooring,veneer,furniture,cabinetry,truss and mine props.Therefore,coppiced wood could supplement non-coppiced wood for industrial applications which require strength.

Structures,properties,and applications of zwitterionic polymers

Zwitterionic polymers have attracted research attention in recent years owing to their unique molecular struc-tures.In the same repeat unit,positive and negative charges are simultaneously located on a pair of cationic and anionic groups;therefore,zwitterionic polymers have a large dipole moment and numerous charged groups.Al-though the molecular chain of the zwitterionic polymer can be maintained in an electrically neutral state overall,the coexistence of the oppositely charged groups confers extremely high polarity and excellent hydrophilicity to the polymer.At the same time,the electricality of the polymer can be further regulated by the environmental pH and salt ions,which greatly broadens the scope of applications in different fields.This review introduces various structures of zwitterionic polymers and analyzes the reasons why zwitterionic polymers exhibit pH responsive-ness,anti-polyelectrolyte effects,and superior electrical conductivity.The application fields are also summarized by generalizing the research status of zwitterionic polymers,including applications in antifouling coatings,drug delivery,wastewater treatment,and sensors,etc.

Study of the Electronic Structure and Optical Properties of Rare Earth Luminescent Materials

Rare earth luminescent materials have attracted significant attention due to their wide-ranging applications in the field of optoelectronics. This study aims to delve into the electronic structure and optical properties of rare earth luminescent materials, with the goal of uncovering their importance in luminescence mechanisms and applications. Through theoretical calculations and experimental methods, we conducted in-depth analyses on materials composed of various rare earth elements. Regarding electronic structure, we utilized computational techniques such as density functional theory to investigate the band structure, valence state distribution, and electronic density of states of rare earth luminescent materials. The results indicate that the electronic structural differences among different rare earth elements notably influence their luminescence performance, providing crucial clues for explaining the luminescence mechanism. In terms of optical properties, we systematically examined the material’s optical behaviors through fluorescence spectroscopy, absorption spectroscopy, and other experimental approaches. We found that rare earth luminescent materials exhibit distinct absorption and emission characteristics at different wavelengths, closely related to the transition processes of their electronic energy levels. Furthermore, we studied the influence of varying doping concentrations and impurities on the material’s optical properties. Experimental outcomes reveal that appropriate doping can effectively regulate the emission intensity and wavelength, offering greater possibilities for material applications. In summary, this study comprehensively analyzed the electronic structure and optical properties of rare earth luminescent materials, providing deep insights into understanding their luminescence mechanisms and potential value in optoelectronic applications. In the future, these research findings will serve as crucial references for the technological advancement in fields such as LEDs, lasers, and bioimaging.

Sialon玻璃的研究与应用

综述了国内外Sialon玻璃的研究进展,简单介绍了玻璃的形成、制备、性能、晶化,讨论了该玻璃的应用前景。

β'-Sialon陶瓷

叙述了β＇－Sialon陶瓷的结构、合成方法──燃烧法、性质及应用。

α-sialon荧光粉的研究进展

氮氧化物发光材料是一种新型的无机发光材料,因其在固态照明方面和显示方面的潜在应用备注瞩目。α-sialon荧光粉是一种新型的氮氧化物发光材料,表现出优异的低热猝灭性、较高的量子效率等。本文首先简要概述了α-sialon的晶体结构,重点分析了影响稀土掺杂的α-sialon荧光粉的发光性能因素,综述了α-sialon荧光粉的制备方法,展望了α-sialon荧光粉未来研究发展方向。

Preparation,properties and applications of natural biomass materials(Ⅻ)Multifunctional acidic heteropolysaccharide:pectin

Pectin is a kind of natural hydrophilic colloid with complicated composition and structure,which has been abundantly found in the cells of higher plants.Pectin has good water solubility,stability,gelling ability and emulsifying ability,as well as safety and non-toxicity,good biocompatibility,biodegradability,and many excellent biological activities such as lowering cholesterol,anti-tumor,anti-oxidation,and lowering blood sugar.Moreover,both its physicochemical properties and functional performance can be further improved by physical,chemical and enzymatic treatments and compound modification upon the active functional groups,such as hydroxyl groups,carboxyl groups and glycosidic bonds.Therefore,pectin has been widely used in many fields,including food industry and pharmaceutical industry.Furthermore,great application potential has emerged in daily-use chemical industry,functional materials,and biodegradable biological materials.In this review,the source,chemical structure,main physicochemical properties and functional characteristics of pectin were briefly introduced.The extraction methods,separation and purification technologies,and modification methods for pectin were also systematically presented.In addition,the situation of application as well as the current problems for pectin and its modified products were summarized.Finally,some of the directions of future research and development of pectin were pointed out.

Progress and prospects in chitosan derivatives:Modification strategies and medical applications

Chitosan(CS)is the only natural alkaline polysaccharide originated from deacetylation of chitin that is the main component of shell from marine organisms.It has great potential medical application due to its broad-spectrum antimicrobial activity and good water solubility originated from its protonated amino groups under acidic condition and abundant hydroxyl groups.However,unprotonated NH_(2)group of CS leads to its poor solubility under physiological condition and limits its diverse applications.Therefore,it is highly necessary to summarize the modification strategies of CS derivatives systematically to help researchers select the most appropriate strategies for their specific applications.Herein,we have summarized the modification strategies of CS derivatives for improving their antimicrobial activity,water solubility,biocompatibility,and mechanical property by chemical reaction and physical integration.And then we have reviewed the CS derivatives in hydrogels,nanoparticles,or coatings for medical application in wound dressing,drug delivery,medical implant.Last but not the least,we have put forward the future perspectives of deep studies about structure-activity relationship and clinical applications of CS derivatives.

Progress on the melanoidins produced by the Maillard reaction of fermented food and traditional Chinese medicine

FMs(Food-borne melanoidins)are brown high molecular weight polymers formed by the Mailiard reaction between carbohydrates and nitrogen-containing compounds during the processing of food or Traditional Chinese Medicine(TCM),and are widely found in food-borne products such as TCM concoctions,bakery,brewing,soy sauce,ferment and other food-borne products.FMs not only have a variety of biological activities,such as antioxidant,antibacterial,immunomodulation,regulation of intestinal flora,etc.,and can change the color,aroma and taste of food.The diversity of its components has become a research hotspot at home and abroad in recent years,with a wide range of application prospects.Therefore,this paper summarizes the existing information on FMs at home and abroad,mainly describes their preparation process,physicochemical properties,structural characteristics and functional activity research progress.Typical FMs,such as coffee,biscuits,wine and soy sauce in daily food,and Polygonatum,Perilla oil,Black ginseng,and Red jujube in T,were highlighted.Summarising the current status of research between the chemistry and pharmacodynamics of relevant FMs and presenting challenges and future recommendations for melanoidin research.In future research on FMs,one should pay more attention to basic research,especially isolation and purification and generation mechanisms,to further demonstrate the biological activity of FMs in vivo and in clinical trials.Thus,the potential value of its existence is deeply exploited to meet the needs of technology,production and health.