S-粗集(singular rough sets)具有两类形式:单向S-粗集(one direction S-rough sets)和双向S-粗集(two direction S-rough sets)。S-粗集具有遗传特征、记忆特征。把S-粗集与材料科学进行学科渗透,互补共享,给出新金属材料的发现-识别...S-粗集(singular rough sets)具有两类形式:单向S-粗集(one direction S-rough sets)和双向S-粗集(two direction S-rough sets)。S-粗集具有遗传特征、记忆特征。把S-粗集与材料科学进行学科渗透,互补共享,给出新金属材料的发现-识别的讨论,利用属性生成模型给出新金属材料的属性值分析,给出的结果与实际相符。S-粗集是粗集研究的一个新方向,是新材料发现-识别的一个新的数学工具。展开更多
The authors discovered in first time that the weight of materials or its gravitational force by earth related to its temperature and its ferromagnetism. An experiment was designed to elevate the temperatures of six di...The authors discovered in first time that the weight of materials or its gravitational force by earth related to its temperature and its ferromagnetism. An experiment was designed to elevate the temperatures of six different materials （Au, Ag, Cu, Fe, Al, Ni） up to 600 ℃and precisely measured their weights. It is found all the materials weigh about 0.33 ‰ - 0. 82 ‰ less. For example the weight of silver sample weighted by a precision electronic scale in a manner of special design decreases about 0.8 ‰, when its temperature is elevated to 600 ℃. Thus different metals＇ gravitational forces or weights are adjusted with temperature variation.展开更多
Nanocellulose composites combine the advantages of nanocellulose and composites. Recently, nanocellulose composites have been received more attentions due to their improved properties and promising broad applications....Nanocellulose composites combine the advantages of nanocellulose and composites. Recently, nanocellulose composites have been received more attentions due to their improved properties and promising broad applications. In the past, rapid progress has been made in the synthesis, properties, and mechanism of nanocellulose composites and potential applications were reported. There are a few reports on the increasing applications of nanocellulose composites with focus on the biomedical field, environmental field, electrode and sensor applications. In this article, the recent development of nanocellulose composites was reviewed via some typical examples. In addition to the synthesis methods, improved properties and potential applications were discussed. The problems and future applications of nanocellulose composites were also suggested.展开更多
Nanocellulose(NC) has attracted much interest in the tissue engineering(TE) field because of its properties including biocompatibility,renewability, non-toxicity, functionality, and excellent mechanical performance. T...Nanocellulose(NC) has attracted much interest in the tissue engineering(TE) field because of its properties including biocompatibility,renewability, non-toxicity, functionality, and excellent mechanical performance. This review mainly focused on the advanced applications of NC-based composites in hard TE including cartilage TE, bone TE, and dental TE, illustrated the processing methods for synthesizing scaffolds including electrospinning, freeze-drying, and 3 D printing, reviewed the current status of hard TE, and presented perspective on the future of TE technology.展开更多
The potential reactions between natural polysaccharides and iodine and their products have been explored for a long time. Due to the complex factors that can in？uence these reactions, a clear-cut mechanism ...The potential reactions between natural polysaccharides and iodine and their products have been explored for a long time. Due to the complex factors that can in？uence these reactions, a clear-cut mechanism has not yet been developed. Starch-iodine complexes, especially the amylose-iodine complex, are the most investigated of the polysaccharide-iodine reactions, and the study of this reaction can be used as a basis for the investigation of other polysaccharide-iodine reactions. In this paper, significant aspects of the reaction were introduced, including the influence of the polysaccharide structure on the properties of the resulting complexes, the relationship between the concentration of CaCl2 and formation of the final products, as well as the form of the polyiodides in these complexes. The interior structure and the surface morphology of the complexes were discussed, along with the progress in research related to this reaction.展开更多
Zero-dimensional metal halide perovskites have captured intense research interest owing to their unique optoelectronic properties.Particularly,metal halides with the ns^(2) electronic configuration are of great intere...Zero-dimensional metal halide perovskites have captured intense research interest owing to their unique optoelectronic properties.Particularly,metal halides with the ns^(2) electronic configuration are of great interest owing to the high-temperature sensitivity of their photoluminescence,which could be applied to remote optical thermometry(ROT).Herein,all-inorganic and lead-free halide perovskite Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O single crystals(SCs)were prepared through the hydrothermal method and showed a strong temperature dependence of photoluminescence lifetime.Upon Te^(4+) doping,the nonemissive Cs_(2)InCl_(5)·H_(2)O SC exhibits a bright orange emission at 660 nm with a wide full width at half maximum of 180 nm.The strong phonon-exciton coupling promotes the formation of self-trapped excitons in the soft lattice of the zero-dimensional Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC.The Te^(4+) ions with the 5 s^(2) electronic configuration endow the Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC with a strong temperaturedependent photoluminescence lifetime.This SC reaches a maximum specific sensitivity of 0.062 K^(-1) at 320 K,thereby showing the potential advantages of indium-based metal halide perovskites in ROT applications.展开更多
60 years ago, in 1958, Ernest Rabinowicz published a 5 page paper titled "The effect of size on the looseness of wear fragments" where he suggested a criterion determining the minimum size of wear particles....60 years ago, in 1958, Ernest Rabinowicz published a 5 page paper titled "The effect of size on the looseness of wear fragments" where he suggested a criterion determining the minimum size of wear particles. The criterion of Rabinowicz is based on the consideration of the interplay of elastic energy stored in "asperities" and the work of separation needed for detaching a wear particle. He was probably the first researcher who explicitly emphasized the role of adhesion in friction and wear. In a recent paper in Nature Communications, Aghababaei, Warner and Molinari confirmed the criterion of Rabinowicz by means of quasi-molecular dynamics and illustrated the exact mechanism of the transition from plastic smoothing to formation of wear debris. This latter paper promoted the criterion of Rabinowicz to a new paradigm for current studies of adhesive wear. The size arguments of Rabinowicz can be applied in the same form also to many other problems, such as brittle-ductile transition during indentation, cutting of materials or ultimate strength of nano-composites.展开更多
Mechanoluminescent(ML)materials can directly convert external mechanical stimulation into light without the need for excitation from other forms of energy,such as light or electricity.This alluring characteristic make...Mechanoluminescent(ML)materials can directly convert external mechanical stimulation into light without the need for excitation from other forms of energy,such as light or electricity.This alluring characteristic makes ML materials potentially applicable in a wide range of areas,including dynamic imaging of force,advanced displays,information code,storage,and anti-counterfeiting encryption.However,current reproducible ML materials are restricted to sulfide-and oxide-based materials.In addition,most of the reported ML materials require pre-irradiation with ultraviolet(UV)lamps or other light sources,which seriously hinders their practical applications.Here,we report a novel ML material,MgF_(2):Mn^(2+),which emits bright red light under an external dynamic force without the need for pre-charging with UV light.The luminescence properties were systematically studied,and the piezophotonic application was demonstrated.More interestingly,unlike the well-known zinc sulfide ML complexes reported previously,a highly transparent ML film was successfully fabricated by incorporating MgF_(2):Mn^(2+)into polydimethylsiloxane(PDMS)matrices.This film is expected to find applications in advanced flexible optoelectronics such as integrated piezophotonics,artificial skin,athletic analytics in sports.展开更多
文摘S-粗集(singular rough sets)具有两类形式:单向S-粗集(one direction S-rough sets)和双向S-粗集(two direction S-rough sets)。S-粗集具有遗传特征、记忆特征。把S-粗集与材料科学进行学科渗透,互补共享,给出新金属材料的发现-识别的讨论,利用属性生成模型给出新金属材料的属性值分析,给出的结果与实际相符。S-粗集是粗集研究的一个新方向,是新材料发现-识别的一个新的数学工具。
文摘The authors discovered in first time that the weight of materials or its gravitational force by earth related to its temperature and its ferromagnetism. An experiment was designed to elevate the temperatures of six different materials （Au, Ag, Cu, Fe, Al, Ni） up to 600 ℃and precisely measured their weights. It is found all the materials weigh about 0.33 ‰ - 0. 82 ‰ less. For example the weight of silver sample weighted by a precision electronic scale in a manner of special design decreases about 0.8 ‰, when its temperature is elevated to 600 ℃. Thus different metals＇ gravitational forces or weights are adjusted with temperature variation.
基金Financial supported from the Fundamental Research Funds for the Central Universities (No. 2017ZY49)the Foundation (No. KF201607) of Key Laboratory of Pulp and Paper Science and Technology of Ministry of Education/Shandong Province of China
文摘Nanocellulose composites combine the advantages of nanocellulose and composites. Recently, nanocellulose composites have been received more attentions due to their improved properties and promising broad applications. In the past, rapid progress has been made in the synthesis, properties, and mechanism of nanocellulose composites and potential applications were reported. There are a few reports on the increasing applications of nanocellulose composites with focus on the biomedical field, environmental field, electrode and sensor applications. In this article, the recent development of nanocellulose composites was reviewed via some typical examples. In addition to the synthesis methods, improved properties and potential applications were discussed. The problems and future applications of nanocellulose composites were also suggested.
基金the special fund for Independent Innovation and Industry Development in the Core Area in Haidian District of Beijing (255-kjc020)
文摘Nanocellulose(NC) has attracted much interest in the tissue engineering(TE) field because of its properties including biocompatibility,renewability, non-toxicity, functionality, and excellent mechanical performance. This review mainly focused on the advanced applications of NC-based composites in hard TE including cartilage TE, bone TE, and dental TE, illustrated the processing methods for synthesizing scaffolds including electrospinning, freeze-drying, and 3 D printing, reviewed the current status of hard TE, and presented perspective on the future of TE technology.
基金supported by the Fundamental Research Funds for the Central Universities(JC2015-03)National Natural Science Foundation of China(31470417)+1 种基金Beijing Municipal Natural Science Foundation(6182031)Author of National Excellent Doctoral Dissertations of China(201458)
文摘The potential reactions between natural polysaccharides and iodine and their products have been explored for a long time. Due to the complex factors that can in？uence these reactions, a clear-cut mechanism has not yet been developed. Starch-iodine complexes, especially the amylose-iodine complex, are the most investigated of the polysaccharide-iodine reactions, and the study of this reaction can be used as a basis for the investigation of other polysaccharide-iodine reactions. In this paper, significant aspects of the reaction were introduced, including the influence of the polysaccharide structure on the properties of the resulting complexes, the relationship between the concentration of CaCl2 and formation of the final products, as well as the form of the polyiodides in these complexes. The interior structure and the surface morphology of the complexes were discussed, along with the progress in research related to this reaction.
基金supported by the National Natural Science Foundation of China(U2001214)the Natural Science Foundation of Guangdong Province(2019B1515120050)the Fundamental Research Funds for the Central Universities。
文摘Zero-dimensional metal halide perovskites have captured intense research interest owing to their unique optoelectronic properties.Particularly,metal halides with the ns^(2) electronic configuration are of great interest owing to the high-temperature sensitivity of their photoluminescence,which could be applied to remote optical thermometry(ROT).Herein,all-inorganic and lead-free halide perovskite Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O single crystals(SCs)were prepared through the hydrothermal method and showed a strong temperature dependence of photoluminescence lifetime.Upon Te^(4+) doping,the nonemissive Cs_(2)InCl_(5)·H_(2)O SC exhibits a bright orange emission at 660 nm with a wide full width at half maximum of 180 nm.The strong phonon-exciton coupling promotes the formation of self-trapped excitons in the soft lattice of the zero-dimensional Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC.The Te^(4+) ions with the 5 s^(2) electronic configuration endow the Te^(4+)-doped Cs_(2)InCl_(5)·H_(2)O SC with a strong temperaturedependent photoluminescence lifetime.This SC reaches a maximum specific sensitivity of 0.062 K^(-1) at 320 K,thereby showing the potential advantages of indium-based metal halide perovskites in ROT applications.
文摘60 years ago, in 1958, Ernest Rabinowicz published a 5 page paper titled "The effect of size on the looseness of wear fragments" where he suggested a criterion determining the minimum size of wear particles. The criterion of Rabinowicz is based on the consideration of the interplay of elastic energy stored in "asperities" and the work of separation needed for detaching a wear particle. He was probably the first researcher who explicitly emphasized the role of adhesion in friction and wear. In a recent paper in Nature Communications, Aghababaei, Warner and Molinari confirmed the criterion of Rabinowicz by means of quasi-molecular dynamics and illustrated the exact mechanism of the transition from plastic smoothing to formation of wear debris. This latter paper promoted the criterion of Rabinowicz to a new paradigm for current studies of adhesive wear. The size arguments of Rabinowicz can be applied in the same form also to many other problems, such as brittle-ductile transition during indentation, cutting of materials or ultimate strength of nano-composites.
基金financial support from the Advanced Talents Incubation Program of Hebei University (521100221006)financial support from the National Natural Science Foundation of China (11974097)+2 种基金the Natural Science Foundation of Hebei Province (A2019201073)support from the National Natural Science Foundation of China (61875136)the Fundamental Research Project of Guangdong Province (2020A1515011315)
文摘Mechanoluminescent(ML)materials can directly convert external mechanical stimulation into light without the need for excitation from other forms of energy,such as light or electricity.This alluring characteristic makes ML materials potentially applicable in a wide range of areas,including dynamic imaging of force,advanced displays,information code,storage,and anti-counterfeiting encryption.However,current reproducible ML materials are restricted to sulfide-and oxide-based materials.In addition,most of the reported ML materials require pre-irradiation with ultraviolet(UV)lamps or other light sources,which seriously hinders their practical applications.Here,we report a novel ML material,MgF_(2):Mn^(2+),which emits bright red light under an external dynamic force without the need for pre-charging with UV light.The luminescence properties were systematically studied,and the piezophotonic application was demonstrated.More interestingly,unlike the well-known zinc sulfide ML complexes reported previously,a highly transparent ML film was successfully fabricated by incorporating MgF_(2):Mn^(2+)into polydimethylsiloxane(PDMS)matrices.This film is expected to find applications in advanced flexible optoelectronics such as integrated piezophotonics,artificial skin,athletic analytics in sports.
