Nanoporous Metals Based on Metallic Glasses:Synthesis,Structure and Functional Applications

Nanoporous metals have emerged as a new class of functional materials with unique structures and properties.Compared to conventional metals and alloys,nanoporous metals possess a high surface area,unique pore size distribution and enhanced catalytic activity,making them highly desirable for a wide range of applications,such as photonics,sensing,supercapacitors and catalysis.In this review paper,we aim to summarize recent advances in the fabrication,structural regulation and functional applications of nanoporous metals and their composites via the dealloying of metallic glasses.Particularly,we will discuss the factors that affect the nanoporous structure,including precursor composition,dealloying conditions and post-treatment methods.We will also cover topics such as the preparation of immiscible nanoporous metals and the control of hierarchical nanoporous structures.Finally,we will provide a brief overview of the current situation and discuss the current challenges and potential research directions in the field.

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.

The growth and expansive applications of amorphous Ga_(2)O_(3)

As a promising ultra-wide bandgap semiconductor material,gallium oxide(Ga_(2)O_(3))is attracting extensive attention of researchers due to its feasible growth process,appropriate bandgap of 4.4 e V-5.3 e V allowing for deep-ultraviolet(deepUV)detection,good physical and chemical stability,high breakdown field strength and electron mobility,etc.Different from the strict processes for controllable crystalline Ga_(2)O_(3)(usually refer to as stable monoclinicβ-Ga_(2)O_(3)),amorphous Ga_(2)O_(3)(a-Ga_(2)O_(3))film can be prepared uniformly at low temperature on a large-area deposition substrate,suggesting great advantages such as low manufacturing cost and excellent flexibility,dispensing with high-temperature and high vacuum techniques.Thus,a-Ga_(2)O_(3)extremely facilitates important applications in various applied fields.Therefore,in this concise review,we summarize several major deposition methods for a-Ga_(2)O_(3)films,of which the characteristics are discussed.Additionally,potential methods to optimize the film properties are proposed by right of the inspiration from some recent studies.Subsequently,the applications of a-Ga_(2)O_(3)thin films,e.g.,in photodetectors,resistive random access memories(RRAMs)and gas sensors,are represented with a fruitful discussion of their structures and operating mechanisms.

Graphene quantum dots:preparations,properties,functionalizations and applications

Zero-dimensional graphene quantum dots(GQDs)exhibit many different properties,such as strong fluorescence,nonzero bandgap and solubility in solvents,compared to two-dimensional graphene.GQDs are biocompatible and have low toxicity;hence,they are widely used in the biomedical field.The edge effect of GQDs is of particular interest because edge modification can regulate the performance of nanomaterials.In this review,various preparation methods for GQDs,which can be divided into three main categories,namely top-down,bottom-up and chemical methods,are discussed.The unique optical,electrical,thermal and magnetic properties of GQDs are reviewed.The functionalization of GQDs by doping with heteroatoms and forming composites with other materials is studied,and the characteristics of these GQDs are also discussed.The applications of these GQDs in the fields of optics,electricity,optoelectronics,biomedicine,energy,agriculture and other emerging interdisciplinary fields are reviewed to highlight the enormous potential of nanomaterials.This review reports on the recent advancement in GQD research and suggests future directions for the development of GQDs.

Kinetics and Benefits of an Unique Assisted Free Bodyweight Squatting System: The DB Method®TM

Squatting movements are used frequently in the activities of daily living and squatting exercises are used to strengthen abdominal core and lower limb muscles. However, many individuals cannot perform a traditional squat. An alternative is to hire a physical trainer or coach for supervision which can be prohibitively expensive. The DB Method® machine is unique and affordable. A product satisfaction descriptive survey to owners of The DB Method machine describes increased gluteal, core, pelvic floor and lower body strength, an improvement in gluteal region shape, and an increase in activity and energy level. A surprising result of the survey was that this DB Method also seemed to strengthen the pelvic floor muscles and, in some cases, to lessen urinary incontinence. In this article, the results of this survey are described as the kinetics of this machine relative to the lower limbs and the pelvic floor muscles. A comparison between traditional squats and The DB Method and the benefits of using The DB Method are discussed.

THE CAUCHY TYPE INTEGRAL FOR M-ANALYTIC FUNCTION AND ITS APPLICATION

In this paper, the Cauchy type integral for M-analytic function is investigated which is by definition the regular solution of the elliptic system f_x+Mf_y=0, where M is a constant m×m matrix without any real eigenvalues and f is an m×q matrix.

Long-period grating inscription on polymer functionalized optical microfibers and its applications in optical sensing

We demonstrated long-period grating(LPG) inscription on polymer functionalized optical microfibers and its applications in optical sensing. Optical microfibers were functionalized with ultraviolet-sensitive polymethyl methacrylate jackets and, thus, LPGs could be inscribed on optical microfibers via point-by-point ultraviolet laser exposure. For a 2 mm long microfiber LPG(MLPG) inscribed on optical microfibers with a diameter of 5.4 μm, a resonant dip of 15 d B at 1377 nm was observed. This MLPG showed a high sensitivity of strain and axial force, i.e.,-1.93 pm∕με and-1.15 pm∕μN, respectively. Although the intrinsic temperature sensitivity of the LPGs is relatively low, i.e.,-12.75 pm∕°C, it can be increased to be-385.11 pm∕°C by appropriate sealing. Benefiting from the small footprint and high sensitivity, MLPGs could have potential applications in optical sensing of strain,axial force, and temperature.

CLIFFORD ALGEBRA,THEORY OF ITS FUNCTION AND THEIR APPLICATION TO MECHANICS

As is Wellknown in both elastic mechanics andfluid mechanics, the plane problems are more convenient than space problems. One of the causes is that there has been a complete theory about the complex Junction and the analytic junction, hut in space problems, the case is quite different.We have no effective method to deal with these problems. In this paper, we first introduces general theories of Clifford algebra. Then we emphatically explain Clifford algebra in three dimensions and establish theories of regular Junction in three dimensions analogically to analytic function in plane. Thus we extend some results of plane problem-la three dimensions or high dimensions. Obviously, it is very important for elastic and fluid mechanics. But because Clifford algebra is not a commutative algebra, we can't simply extend the results of two dimensions to high dimensions. The left problems are yet to be found out.

AN ASYMPTOTIC EXPANSION FORMULA OF KERNEL FUNCTION FOR QUASI FOURIER-LEGENDRE SERIES AND ITS APPLICATION

Is this paper we shall give cm asymptotic expansion formula of the kernel functim for the Quasi Faurier-Legendre series on an ellipse, whose error is 0(1/n2) and then applying it we shall sham an analogue of an exact result in trigonometric series.

Early application of percutaneous neuromuscular electric stimulation in interfering motor function of limbs and difference in temperature of axilla of patients with ischemic stroke

BACKGROUND： Temperature of axilla could be affected due to motor dysfunction of limbs and neural changes of vessel after ischemic stroke. OBJECTIVE： To observe the effect of percutaneous neuromuscular electric stimulation （PNES） on difference in temperature of axilla and analyze the relationship between function of limbs and difference in temperature of axilla. DESIGN： Randomized grouping and controlled observation SETTING： Department of Neurology, General Hospital of Shenyang Military Area Command of Chinese PLA PARTICIPANTS： Sixty patients with ischemic stroke were selected from Neurological Department of General Hospital of Shenyang Military Area Command of Chinese PLA from January to June 2003. All cases were diagnosed with clinical diagnosis criteria of ischemic stroke established by the Fourth Chinese Classification of Cerebrovasular Disease and CT examination and received neuromuscular electric stimulation （NES）. Patients were randomly divided into control group and treatment group with 30 in each group. METHODS： Control group： Patients received routinely neurological therapy. Treatment group： Except routine therapy, patients suffered from NES at 48 hours after hospitalization. NMT-91 NES equipment was used to stimulated injured limbs with low frequency once 30 minutes a day in total of 10 times a course, especially extensor muscle of upper limb and flexor muscle of lower limb. Prescription of hemiplegia was internally decided by equipment with the output frequency of 200 Hz. Intensity of electric output could cause muscle contraction. The therapy needed two or three courses. Temperature of bilateral axilla was measured every day to calculate the difference with the formula of （temperature of axilla on the injured side - temperature of axilla on the healthy side）. Motor function of limbs was measured with FugI-Meyer Motor Assessment （FMA） during hospitalization and at 2 and 4 hours after hospitalization. Among 90 points, upper and lower limb function was 54, equilibrium function 10, sensory function 10, and motion of joint 16. The higher the scores were, the better the function was. Correlation of data was dealt with linear correlation analysis. MAIN OUTCOME MEASURES ： Assessment and correlation between difference in temperature of axilla and motor function of injured limbs during hospitalization and at 2 and 4 weeks after hospitalization. RESULTS： All 60 patients with ischemic stroke were involved in the final analysis. ① Difference in temperature： Difference of 2 and 4 weeks after hospitalization was lower than that in control group and at just hospitalization [treatment group： （0.056±0.000）, （0.024±0.003） ℃; control group： （0.250±0.001）, （0.131 ±0.001）℃; hospitalization; （0.513±0.001） ℃, P 〈 0.05-0,01]. ② FMA scores： Scores of 2 and 4 weeks after hospitalization were higher than those in control group and at just hospitalization [treatment group; （43.50±15.09）, （67.97 ±18.21） points; control group： （33.33 ±13.54）, （40.87±19.34） points; hospitalization： （26.43 ±11.87） points, P 〈 0.05-0.01]. ③ Correlation： Difference in temperature of axilla was negative correlation with FMA scores （c=- -0.255 1, P 〈 0.05）. CONCLUSION： ① PNES can accelerate recovery of limb function and decrease temperature of axilla of patients with ischemic stroke. ② The lower the difference in temperature is, the better the functional recovery is.

An Integral Representation for the Weighted Geometric Mean and Its Applications

By virtue of Cauchy’s integral formula in the theory of complex functions,the authors establish an integral representation for the weighted geometric mean,apply this newly established integral representation to show that the weighted geometric mean is a complete Bernstein function,and find a new proof of the well-known weighted arithmetic-geometric mean inequality.

From low-dimensional materials to complex superstructures:A review and outlook

Low-dimensional materials have attracted increasing attention due to their guiding significance for material preparation and potential wide-ranging applications.Through the controllable synthesis and suitably designed fusion of lowdimensional materials into ordered complex superstructures,it has become an effective way to explore new properties of materials and construct structures meeting new application needs.Based on low-dimensional materials such as metal oxides,copolymers,metal-organic complexes,and organic crystals,great efforts have been devoted to the design and construction of complex superstructures with regular repeatability.A series of unique cases including multi-block,core/multi-shell,hyperbranched and network structures have been reported,which has promoted the development of the field of material preparation.Herein,we summarize representative progress of low-dimensional complex superstructures in a reasonable structure classification manner.Ultimately,the existing challenges are discussed,and an outlook is given for future study of precise construction of superstructures as well as exploitation of potential applications.

Antichains and their application for enumerating ternary logic functions

MUKAIDONO proposed and systematically investigated the theory of regular ternary logic functions that meets the need of uncertain inferences. The enumeration of ternary logic functions is very complicated and several results have been obtained only in the case where the number of variables is less than 7. In this letter we offer a new possible way to solve the prob-

Acoustic transfer function of cavity and its application to rapid evaluation of sound field at low frequency band

A new method to obtain numerical solution of Acoustic Transfer Function (ATF) by BEM is presented. For a simply supported panel backed by a rectangular cavity at low frequency band (0-200 Hz), the frequency property of ATF is analyzed. The relation between the accuracy of the rapid evaluation of sound field and the discretization schemes of the vibrational panel is discussed. The result shows that the method to obtain ATF and the rapid evaluation of sound field using the ATF is suitable to low frequency band. If an appropriate discretization scheme is choosed based on the frequency involved and the effort to obtain ATF, the accuracy of the rapid evaluation of sound field is acceptable.

Application and measurement of underwater acoustic reciprocity transfer functions in reverberant sound field

The reciprocity measurement theory in anomalous reverberant sound fields was investigated.An improved method Was proposed due to the interrelated errors.The source volume velocity Was corrected by spatial average of measurement results and evaluation of the reverberant sound field influence on acoustic energy density.The result was validated in underwater experiment,corrected reciprocity measurement results were almost the same as direct measurement results.It indicates that reverberant sound field does not affect the validitv of the principle,but influences the obtainment of source volume velocity,then influences the measurement of transfer functions with the principle.The proposed method is simple and effective in anomalous reverberant sound fields.The study mav be valuable for the applications which are based on the principle.