The synthetical soft magnetic properties including d.c. and a.c. magnetic properties and pulse magnetic property are reported for a newly-developed nanocrystalline Fe73.5Cu1 Nb1.5V1.5Si13.5B9 alloy The new alloy posse...The synthetical soft magnetic properties including d.c. and a.c. magnetic properties and pulse magnetic property are reported for a newly-developed nanocrystalline Fe73.5Cu1 Nb1.5V1.5Si13.5B9 alloy The new alloy possesses high d.c. relative initial permeability of 12.5×104 and low coerciv ity of 0.54 A/m. Under the conditions of Bm=0.3 T, f=100 kHz and Bm=0.2 T, f=200 kHz the core losses of the new alloy are 543 kW·m-3 and 834 kW.m-3, respectively which can be compa rable with those of nanocrystalline Fe73.5Cu1Nb3Si13.5B9 alloy. The analyses of core losses have been carried out in the wider range of f=20~104 kHz and Bm=0.0025~0.8 T and the approxi mate expression P(kW·m-3)=1.803 B:f1.77 has been obtained. The analyses of core losses in the range of f=20~104 kHz and Bmf=(10~40)×103(T.Hz) have shown that the core loss and the corresponding amplitude permeability roughly vary as P = 2.347×10-6(Bmf)1.97f-0.2231 and μa = 9.56× 105f-0.7464, respectively for the given product B.f. Some practical applica tions have also been mentioned.展开更多
Arachidonic acid (AA) is one of the most important PUFAs (polyunsaturated fatty acids) in human body. A high-yield arachidonic acid-producing strain (mortierella alpina) was selected by ion implantation (the relative ...Arachidonic acid (AA) is one of the most important PUFAs (polyunsaturated fatty acids) in human body. A high-yield arachidonic acid-producing strain (mortierella alpina) was selected by ion implantation (the relative content of arachidonic acid is 70.2% among all fatty acids). This paper mainly introduced the structure, distribution, source, physiologic healthcare function and application of AA.展开更多
A general version of the inverted exponential distribution is introduced, studied and analyzed. This generalization depends on the method of Marshall-Olkin to extend a family of distributions. Some statistical and rel...A general version of the inverted exponential distribution is introduced, studied and analyzed. This generalization depends on the method of Marshall-Olkin to extend a family of distributions. Some statistical and reliability properties of this family are studied. In addition, numerical estimation of the maximum likelihood estimate(MLE) parameters are discussed in details. As an application, some real data sets are analyzed and it is observed that the presented family provides a better fit than some other known distributions.展开更多
Low-dimensional black phosphorus(BP)is a class of nanomaterial derived from layered semiconductor BP which has gained tremendous attention in a variety of fields,owing to its uncommon structural features and appealing...Low-dimensional black phosphorus(BP)is a class of nanomaterial derived from layered semiconductor BP which has gained tremendous attention in a variety of fields,owing to its uncommon structural features and appealing physical properties.More surprisingly,it has addressed current biomedical obstacles due to its orthorhombic puckered honeycomb crystal structure and unique properties such as tunable direct-bandgap,high carrier mobility,and exceptional photo-responsiveness.However,few reviews have focused on the interactions of low-dimensional BP’s physical properties with its biomedical performances.Herein,we discuss the physical properties of low-dimensional BP and potential biomedical applications associated with these physical properties.Moreover,different preparation methods,surface modification techniques,and future challenges,as well as future outlooks,are presented.This comprehensive review will provide a clear understanding of the relationship between lowdimensional BP’s physical properties and biomedical performances,with the ultimate goal of better knowledge of utilizing BP.展开更多
Two-dimensional(2D) materials with potential applications in photonic and optoelectronic devices have attracted increasing attention due to their unique structures and captivating properties. However, generation of st...Two-dimensional(2D) materials with potential applications in photonic and optoelectronic devices have attracted increasing attention due to their unique structures and captivating properties. However, generation of stable high-energy ultrashort pulses requires further boosting of these materials' optical properties, such as higher damage threshold and larger modulation depth. Here we investigate a new type of heterostructure material with uniformity by employing the magnetron sputtering technique. Heterostructure materials are synthesized with van der Waals heterostructures consisting of MoS_2 and Sb_2Te_3. The bandgap, carrier mobility, and carrier concentration of the MoS_2-Sb_2Te_3-MoS_2 heterostructure materials are calculated theoretically. By using these materials as saturable absorbers(SAs), applications in fiber lasers with Q-switching and mode-locking states are demonstrated experimentally. The modulation depth and damage threshold of SAs are measured to be 64.17%and 14.13 J∕cm^2, respectively. Both theoretical and experimental results indicate that MoS_2-Sb_2Te_3-MoS_2 heterostructure materials have large modulation depth, and can resist high power during the generation of ultrashort pulses. The MoS_2-Sb_2Te_3-MoS_2 heterostructure materials have the advantages of low cost, high reliability, and suitability for mass production, and provide a promising solution for the development of 2D-material-based devices with desirable electronic and optoelectronic properties.展开更多
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 pu...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.展开更多
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...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.展开更多
Due to the properties and high reactivity of hydrazine,it is mainly used as rocket fuel not only in its pure form but also in combination with 1,1-dimethylhydrazine and oxidizers(nitrogen tetroxide or nitric acid)form...Due to the properties and high reactivity of hydrazine,it is mainly used as rocket fuel not only in its pure form but also in combination with 1,1-dimethylhydrazine and oxidizers(nitrogen tetroxide or nitric acid)forming a self-igniting mixture with oxidizers.Aerozine 50 and UH 25(a mixture of 75%UDMH(unsymmetrical dimethylhydrazine)and 25%hydrazine hydrate)are the best-known hydrazine mixtures with different hydrazine concentrations.The review addresses the use of hydrazine and its derivatives as fuel.Hydrazine is employed in fuel cells(with air oxygen as an oxidizer)to generate electrochemical energy for transport vehicles.Hydrazine is widely used as monopropellant to design low-thrust rocket engines for orientation and stabilization systems in space vehicles,as well as in energy units.The review also addresses such hydrazine derivatives as methylhydrazine,1,1-dimethylhydrazine,hydrazine monoperchlorate,hydrazine diperchlorate,hydrazine diammonium tetraperchlorate,hydrazine mononitrate,hydrazine dinitrate,hydrazine nitroformate,hydrazine azides,tetrafluorohydrazine,etc.as well as composite propellants,and gel rocket propellants based on hydrazine.The materials in the review can be used as reference information on hydrazine fuels.展开更多
Plasma radiative properties play a pivotal role both in nuclear fusion and astrophysics.They are essential to analyze and explain experiments or observations and also in radiative-hydrodynamics simulations.Their compu...Plasma radiative properties play a pivotal role both in nuclear fusion and astrophysics.They are essential to analyze and explain experiments or observations and also in radiative-hydrodynamics simulations.Their computation requires the generation of large atomic databases and the calculation,by solving a set of rate equations,of a huge number of atomic level populations in wide ranges of plasma conditions.These facts make that,for example,radiative-hydrodynamics in-line simulations be almost infeasible.This has lead to develop analytical expressions based on the parametrization of radiative properties.However,most of them are accurate only for coronal or local thermodynamic equilibrium.In this work we present a code for the parametrization of plasma radiative properties of mono-component plasmas,in terms of plasma density and temperature,such as radiative power loss,the Planck and Rosseland mean opacities and the average ionization,which is valid for steady-state optically thin plasmas in wide ranges of plasma densities and temperatures.Furthermore,we also present some applications of this parametrization such as the analysis of the optical depth and radiative character of plasmas,the use to perform diagnostics of the electron temperature,the determination of mean radiative properties for multicomponent plasmas and the analysis of radiative cooling instabilities in some kind of experiments on high-energy density laboratory astrophysics.Finally,to ease the use of the code for the parametrization,this one has been integrated in a user interface and brief comments about it are presented.展开更多
As an emerging and efficient polymerization methodology,activated internal alkyne-based polymerization has been considered as a powerful tool for the construction of polymers with diverse architectures and versatile f...As an emerging and efficient polymerization methodology,activated internal alkyne-based polymerization has been considered as a powerful tool for the construction of polymers with diverse architectures and versatile functions.This review focuses on the recent progresses in the polymerization using mono-activated,di-activated,in-situ generated,ring-strained ethynyl groups as substrates,coupling with post-modification on premade polymers containing activated internal ethynyl moieties.Representative examples are used to illustrate the fundamental design strategy,the development of polymerization and post-functionalization,along with the properties and potential applications of the prepared polymers.Moreover,the challenges and perspectives in terms of new-type active alkynes,green polymerization methodology,tailored regio-/stereoselectivity modulation,and potentially expanded application in this area are also discussed.展开更多
文摘The synthetical soft magnetic properties including d.c. and a.c. magnetic properties and pulse magnetic property are reported for a newly-developed nanocrystalline Fe73.5Cu1 Nb1.5V1.5Si13.5B9 alloy The new alloy possesses high d.c. relative initial permeability of 12.5×104 and low coerciv ity of 0.54 A/m. Under the conditions of Bm=0.3 T, f=100 kHz and Bm=0.2 T, f=200 kHz the core losses of the new alloy are 543 kW·m-3 and 834 kW.m-3, respectively which can be compa rable with those of nanocrystalline Fe73.5Cu1Nb3Si13.5B9 alloy. The analyses of core losses have been carried out in the wider range of f=20~104 kHz and Bm=0.0025~0.8 T and the approxi mate expression P(kW·m-3)=1.803 B:f1.77 has been obtained. The analyses of core losses in the range of f=20~104 kHz and Bmf=(10~40)×103(T.Hz) have shown that the core loss and the corresponding amplitude permeability roughly vary as P = 2.347×10-6(Bmf)1.97f-0.2231 and μa = 9.56× 105f-0.7464, respectively for the given product B.f. Some practical applica tions have also been mentioned.
文摘Arachidonic acid (AA) is one of the most important PUFAs (polyunsaturated fatty acids) in human body. A high-yield arachidonic acid-producing strain (mortierella alpina) was selected by ion implantation (the relative content of arachidonic acid is 70.2% among all fatty acids). This paper mainly introduced the structure, distribution, source, physiologic healthcare function and application of AA.
基金supported by the Research Center of the Female Scientific and Medical Colleges,Deanship of Scientific Research,King Saud University
文摘A general version of the inverted exponential distribution is introduced, studied and analyzed. This generalization depends on the method of Marshall-Olkin to extend a family of distributions. Some statistical and reliability properties of this family are studied. In addition, numerical estimation of the maximum likelihood estimate(MLE) parameters are discussed in details. As an application, some real data sets are analyzed and it is observed that the presented family provides a better fit than some other known distributions.
基金supported by the National Key Research and Development Program of China(No.2020YFA0210800)the Major Project of Science and Technology of Fujian Province(2020HZ06006)+2 种基金the National Natural Science Foundation of China(No.22027805,21804068,U21A20377 and 21874024)the joint re-search projects of Health and Education Commission of Fujian Province(No.2019-WJ-20)the Natural Science Foundation of Fujian Province(No.2020J02012)。
文摘Low-dimensional black phosphorus(BP)is a class of nanomaterial derived from layered semiconductor BP which has gained tremendous attention in a variety of fields,owing to its uncommon structural features and appealing physical properties.More surprisingly,it has addressed current biomedical obstacles due to its orthorhombic puckered honeycomb crystal structure and unique properties such as tunable direct-bandgap,high carrier mobility,and exceptional photo-responsiveness.However,few reviews have focused on the interactions of low-dimensional BP’s physical properties with its biomedical performances.Herein,we discuss the physical properties of low-dimensional BP and potential biomedical applications associated with these physical properties.Moreover,different preparation methods,surface modification techniques,and future challenges,as well as future outlooks,are presented.This comprehensive review will provide a clear understanding of the relationship between lowdimensional BP’s physical properties and biomedical performances,with the ultimate goal of better knowledge of utilizing BP.
基金National Natural Science Foundation of China(NSFC)(11674036)Beijing University of Posts and Telecommunications(BUPT)(IPOC2016ZT04,IPOC2017ZZ05)+2 种基金Beijing Youth Top-Notch Talent Support Program(2017000026833ZK08)Special Program for Applied Research on Super Computation of the NSFC Guangdong Joint Fund(U1501501)XAFS Station(BL14W1)
文摘Two-dimensional(2D) materials with potential applications in photonic and optoelectronic devices have attracted increasing attention due to their unique structures and captivating properties. However, generation of stable high-energy ultrashort pulses requires further boosting of these materials' optical properties, such as higher damage threshold and larger modulation depth. Here we investigate a new type of heterostructure material with uniformity by employing the magnetron sputtering technique. Heterostructure materials are synthesized with van der Waals heterostructures consisting of MoS_2 and Sb_2Te_3. The bandgap, carrier mobility, and carrier concentration of the MoS_2-Sb_2Te_3-MoS_2 heterostructure materials are calculated theoretically. By using these materials as saturable absorbers(SAs), applications in fiber lasers with Q-switching and mode-locking states are demonstrated experimentally. The modulation depth and damage threshold of SAs are measured to be 64.17%and 14.13 J∕cm^2, respectively. Both theoretical and experimental results indicate that MoS_2-Sb_2Te_3-MoS_2 heterostructure materials have large modulation depth, and can resist high power during the generation of ultrashort pulses. The MoS_2-Sb_2Te_3-MoS_2 heterostructure materials have the advantages of low cost, high reliability, and suitability for mass production, and provide a promising solution for the development of 2D-material-based devices with desirable electronic and optoelectronic properties.
基金the financial support from the National Natural Science Foundation of China(Grant Nos.11674161,11174122 and 11134004)the Six Big Talent Peak Project from Jiangsu Province(Grant No.XCL-004)open project of National Laboratory of Solid State Microstructures,Nanjing University(Grant No.M28026)
文摘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.
基金the National Natural Science Foundation of China (No. 11364011)Guangxi Natural Science Foundation (Nos. 2015GXNSFAA139004, and 2017GXNSFAA198121)
文摘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.
文摘Due to the properties and high reactivity of hydrazine,it is mainly used as rocket fuel not only in its pure form but also in combination with 1,1-dimethylhydrazine and oxidizers(nitrogen tetroxide or nitric acid)forming a self-igniting mixture with oxidizers.Aerozine 50 and UH 25(a mixture of 75%UDMH(unsymmetrical dimethylhydrazine)and 25%hydrazine hydrate)are the best-known hydrazine mixtures with different hydrazine concentrations.The review addresses the use of hydrazine and its derivatives as fuel.Hydrazine is employed in fuel cells(with air oxygen as an oxidizer)to generate electrochemical energy for transport vehicles.Hydrazine is widely used as monopropellant to design low-thrust rocket engines for orientation and stabilization systems in space vehicles,as well as in energy units.The review also addresses such hydrazine derivatives as methylhydrazine,1,1-dimethylhydrazine,hydrazine monoperchlorate,hydrazine diperchlorate,hydrazine diammonium tetraperchlorate,hydrazine mononitrate,hydrazine dinitrate,hydrazine nitroformate,hydrazine azides,tetrafluorohydrazine,etc.as well as composite propellants,and gel rocket propellants based on hydrazine.The materials in the review can be used as reference information on hydrazine fuels.
基金the Research Project of the Spanish Government(ENE2009-11208/FTN)the Keep in touch and ToIFE Projects of the European Union.
文摘Plasma radiative properties play a pivotal role both in nuclear fusion and astrophysics.They are essential to analyze and explain experiments or observations and also in radiative-hydrodynamics simulations.Their computation requires the generation of large atomic databases and the calculation,by solving a set of rate equations,of a huge number of atomic level populations in wide ranges of plasma conditions.These facts make that,for example,radiative-hydrodynamics in-line simulations be almost infeasible.This has lead to develop analytical expressions based on the parametrization of radiative properties.However,most of them are accurate only for coronal or local thermodynamic equilibrium.In this work we present a code for the parametrization of plasma radiative properties of mono-component plasmas,in terms of plasma density and temperature,such as radiative power loss,the Planck and Rosseland mean opacities and the average ionization,which is valid for steady-state optically thin plasmas in wide ranges of plasma densities and temperatures.Furthermore,we also present some applications of this parametrization such as the analysis of the optical depth and radiative character of plasmas,the use to perform diagnostics of the electron temperature,the determination of mean radiative properties for multicomponent plasmas and the analysis of radiative cooling instabilities in some kind of experiments on high-energy density laboratory astrophysics.Finally,to ease the use of the code for the parametrization,this one has been integrated in a user interface and brief comments about it are presented.
基金supported by the National Natural Science Foundation of China(21788102,21901075,22001078)the Natural Science Foundation of Guangdong Province(2016A030312002,2019B030301003)the Innovation and Technology Commission of Hong Kong(ITCCNERC14S01).
文摘As an emerging and efficient polymerization methodology,activated internal alkyne-based polymerization has been considered as a powerful tool for the construction of polymers with diverse architectures and versatile functions.This review focuses on the recent progresses in the polymerization using mono-activated,di-activated,in-situ generated,ring-strained ethynyl groups as substrates,coupling with post-modification on premade polymers containing activated internal ethynyl moieties.Representative examples are used to illustrate the fundamental design strategy,the development of polymerization and post-functionalization,along with the properties and potential applications of the prepared polymers.Moreover,the challenges and perspectives in terms of new-type active alkynes,green polymerization methodology,tailored regio-/stereoselectivity modulation,and potentially expanded application in this area are also discussed.