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Optimizing electrode materials performance and improving the energy density of supercapacitors is a hot research topic. The complex hollow sphere structure material, as a supercapacitor electrode m...

In this paper, a novel type of electrode material for high-performance hybrid supercapacitors is designed. The electrode mainly uses nitrogen-doped atoms to anchor the nickel-cobalt layered double hydroxide on the inner wall of wood-derived carbon tracheids from Chinese fir wood scraps. The specific capacity of the composite single electrode is 14.26 mAh cm−2 at 10 mA cm−2. The hybrid supercapacitor with a composite electrode cathode and nitrogen-doped wood-derived monolithic carbon materials as the anode has a high specific capacitance of 4.74 F cm−2 at 5 mA cm−2, and the capacitance retention rate is 93.15% after 8000 charge-discharge cycles. The highest energy density and power density reach 1.48 mWh cm−2 and 22.40 mW cm−2, respectively. After doping with nitrogen, the combination with the nickel-cobalt layered double hydroxide is more uniform and stable, and the capacitance and cycling stability are significantly improved.

Graphene and single-wall carbon nanotube (SWCNT) have attracted great attention because of their ultra-high thermal conductivity. However, there are few works exploring the relations of their thermal conductivity quantitatively. The carbon nanocone (CNC) is a graded structure fall in between graphene disk (GD) and SWCNT. We perform non-equilibrium molecular dynamics (NEMD) simulation to study the thermal conductivity of CNC with different apex angles, and then compare them with that of GD and SWCNT. Our results show that, different from the homogeneous thermal conductivity in SWCNT, the CNC also has a natural graded thermal conductivity which is similar to the GD. Unexpectedly, the graded rate keeps almost the same when the apex angle decreases from 180{\deg} (GD) to 19{\deg}, but then suddenly declines to zero when the apex angle decreases from 19{\deg} to 0{\deg} (SWCNT). What is more interesting, the graded effect is not diminished when the interatomic force constant is weakened and mean free path is shorten. That is, besides nanoscale, the graded effect can be observed in macroscale graphene or CNC structures., Comment: carbon nanocone, graphene disk, single-wall carbon nanotubes, graded thermal conductivity

This paper presents a vision based robotic system to handle the picking problem involved in automatic express package dispatching. By utilizing two RealSense RGB-D cameras and one UR10 industrial robot, package dispatching task which is usually done by human can be completed automatically. In order to determine grasp point for overlapped deformable objects, we improved the sampling algorithm proposed by the group in Berkeley to directly generate grasp candidate from depth images. For the purpose of package recognition, the deep network framework YOLO is integrated. We also designed a multi-modal robot hand composed of a two-fingered gripper and a vacuum suction cup to deal with different kinds of packages. All the technologies have been integrated in a work cell which simulates the practical conditions of an express package dispatching scenario. The proposed system is verified by experiments conducted for two typical express items., Comment: The 2019 IEEE International Conference on Real-time Computing and Robotics

In this paper, the TiO 2 @void@SiO 2 rattle type core shell structure nanoparticles were prepared through calcination of the precursor TOC@SiO 2 which was synthesized from titanyl oxalate complex (TOC) and tetraethyl orthosilicate (TEOS) with co-precipitation in a mixture solvent of ethanol and ammonia. The TOC was prepared from H 4 TiO 4 and oxalic acid dihydrate, and the mole ratio of H 4 TiO 4 to oxalic acid dihydrate was a key factor to form core shell structure. When the mole ratio was 1–2, the core shell structure nanoparticles with void could be obtained. But if the ratio was 1, we get merely the nanoparticles with uniform mixtures of SiO 2 and TiO 2 . Scanning and transmission electron microscopic techniques (SEM & TEM), particle size distribution, Brunauer–Emmett–Teller method (BET), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and X-ray diffraction method (XRD) were employed to characterize the structure and properties of the final particles as well as the precursors. The diameter of core part, the thickness of void space and the thickness of the shell for the TiO 2 @void@SiO 2 particle were about 60 nm, 2 nm and 12 nm, respectively. The TiO 2 core was anatase form. The SiO 2 shell was amorphous with ca . 3.5 nm mesopores. Methylene blue (MB) was used to evaluate the photocatalytic property of the TiO 2 @void@SiO 2 particles. The result showed that photodegradation of MB on TiO 2 @void@SiO 2 gave almost the same degeration ratio as on P-25 at last, but the rattle type structure started its photocatalytic property somewhat slower than P-25.

In order to detect trace methane (CH4) with non contact, the proposed manuscript describes high sensitivity trace methane detector using quantum cascaded laser (QCL) with centre wavelength at 7.5 μm, which is based on combination of Tunable Diode Laser Absorption Spectroscopy (TDLAS) and Wavelength Modulation Spectroscopy (WMS). Under room temperature, the spectrum of QCL can scan CH4 absorption line via adjusting the injection current of QCL. Meanwhile, a compact herriott cell (40 cm long and 800 ml volume) is utilized to achieve a total optical path with 16 meters length. The aforementioned detector is applied to detect CH4 with different concentrations, results show that the relative detection error is less than 7%, the lowest detection is 1×10-6. Meanwhile, the researchers can detect other gases through replace lasers with different wavelength.Read Complete Article at ijSciences: V4201509839 AND DOI: http://dx.doi.org/10.18483/ijSci.839

The polarization imaging detection technology increased the polarization information on the basis of the intensity imaging, which is extensive application in the military and civil and other fields, the research on the polarization characteristics of target is particularly important. The research of the polarization reflection model was introduced in this paper, which describes the scattering vector light energy distribution in reflecting hemisphere polarization characteristics, the target polarization characteristics test system solutions was put forward, by the irradiation light source, measuring turntable and camera, etc, which illuminate light source shall direct light source, with laser light sources and xenon lamp light source, light source can be replaced according to the test need; Hemispherical structure is used in measuring circumarotate placed near its base material sample, equipped with azimuth and pitching rotation mechanism, the manual in order to adjust the azimuth Angle and high Angle observation; Measuring camera pump works, through the different in the way of motor control polaroid polarization test, to ensure the accuracy of measurement and imaging resolution. The test platform has set up by existing laboratory equipment, the laser is 532 nm, line polaroid camera, at the same time also set the sending and receiving optical system. According to the different materials such as wood, metal, plastic, azimuth Angle and zenith Angle in different observation conditions, measurement of target in the polarization scattering properties of different exposure conditions, implementation of hemisphere space pBRDF measurement.

The laser transmission characteristics affected in the complex channel environment, which limits the performance of laser equipment and engineering application severely. The article aim at the influence of laser transmission in atmospheric and seawater channels, summarizes the foreign researching work of the simulation and comprehensive test regarding to the laser transmission characteristics in complex environment. And researched the theory of atmospheric turbulence effect, water attenuation features, and put forward the corresponding theoretical model. And researched the simulate technology of atmospheric channel and sea water channel, put forward the analog device plan, adopt the similar theory of flowing to simulate the atmosphere turbulence .When the flowing has the same condition of geometric limits including the same Reynolds, they must be similar to each other in the motivation despite of the difference in the size, speed, and intrinsic quality. On this basis, set up a device for complex channel simulation and comprehensive testing, the overall design of the structure of the device, Hot and Cold Air Convection Simulation of Atmospheric Turbulence, mainly consists of cell body, heating systems, cooling systems, automatic control system. he simulator provides platform and method for the basic research of laser transmission characteristics in the domestic.

In this paper, we prepared the rattle type nanoparticles ZnO@void@SiO2 by two successive coating processes, followed by heat treatment. The carbon layer was formed over ZnO surface with the aid of the hydrothermal treatment of glucose. Then the resulting composite was used to fabricate a silica shell on the surface by sol–gel method. Finally, ZnO particles were released but still trapped inside the silica hollow after calcination, that is, ZnO@void@SiO2. The composites were characterized by scanning and transmission electron microscope, N2 adsorption experiment, X-ray diffraction, Fourier transform infrared spectroscopy and UV-Vis absorption spectra. The rattle type structure was conformed and the sphere-like structure with the average size of 70 nm and hexagonal wurtzite crystal structure were also observed. The measurement results of optical properties showed even though ZnO@C@SiO2 presented no photocatalysis, ZnO@void@SiO2 showed high activity even the ZnO core was encapsulated with the SiO2 hollow.

A method of laser energy density distribution measurement is presented in this paper. Dot-matrix method and CCD imaging method are combined in pulse laser far-distance energy density measurement system. The laser energy data is received by detectors on the reflective board, and the laser spot reflected by the reflective board is acquired by the CCD camera. The relation of laser spot image gray and energy data is gotten by image processing algorithms, and energy density distribution is analyzed according to the model of laser energy. Algorithms principle and process are presented detailedly in this paper.

High-power lasers are widely used in the field of industry, science and military. But there is no standard method for characterization and diagnosis of high-power laser beam quality for a long time, which brings great difficulties to the performance test of high-power laser systems. So it is necessary to measure the beam quality for high-power lasers and evaluate the performance of the laser systems scientifically. There are many traditional methods for beam quality determination, such as product of beam divergence angle and beam width, encircled energy ratio, Strehi ratio, diffraction limit factor and beam propagation factor M2, and so on. The paper made a deep analysis for these methods and chose M2 factor as a key parameter to determine the beam quality, according to which, A kind of beam quality measurement device was developed. Experiments showed that this device can describe the laser beam intensity distribution in two-dimension and three-dimension space correctly, which can also give the value of beam width, beam divergence and beam pointing stability in real-time.

This article discussed detailedly the framework and key technologies of omni-azimuth laser target identification and communication system. Including the whole technological scheme which can realize omni-bearing, The article describes the structure of electric control system (multi-machine system design, parallel processing and so on) and some key technologies about the Laser selection, signal processing and the character identification of an omni-bearing laser target identification system.

In this paper we have described the fundamental principle and the concrete means of two-dimensional closed loop dynamic inspection system with laser scan. We have made an inquiry into the basic factors of affecting system stability and accuracy, and have given the concrete experimental data.

This article describes Omni-directional laser digital communication system, discusses the whole design idea of the system and the basic work principle, and describes in detail the hardware configuration and some pivotal technology solution in software.

In machining rotating body parts, which make up a large ratio among all parts to be worked, the radial size and axial size of any locations must be inspected. The photo- electronic 2D auto-inspecting system for rotating body parts made by us has been already used in a factory. A laser- scanned measuring system and a grating displacement measuring system have been adopted to measure the diameter and the axial size of each section respectively. This system can also be used to measure various formal and positional errors, and shapes of rotating body pats. This paper mainly describes the working principles, some problems related to the design and accuracy analysis.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper describes a photoelectric non-contact surface displacement measuring system using reflection light displacement differentiate method. In this system light source is semiconductor laser, photoelectric receiver is semiconductor position sensor device, using transverse photoelectromotive force effect in the PSD's p-n junction to detect irradiates position of incident light point. In has accurate, fast and harmless characteristics. In order to improve measurement accuracy, a microprocessor is added into this system to complete digital filter, linear correcting and statistic processing in the course of measurement. Especially, this paper introduces stabilizing electronically light, extracting PSD signals and processing data with computer, etc in detail.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A general method was developed for the preparation of various functional rattle-type microspheres possessing a movable inner core with different components and morphologies and a mesoporous silica shell. In this process, the cross-linked poly(methyl acrylic acid) (PMAA) sandwiched layer was used as a sacrificial layer for coating the functional cores as well as the reaction locus for the deposition of the outer silica layer via a sol–gel method in the presence of n-octadecyltrimethoxysilane (C18TMS) as the pore-directing agent for tri-layer microspheres. The mesoporous rattle-type microspheres were produced through calcination of the corresponding tri-layer microspheres at high temperature, during which the rattle-structure microspheres were formed through decomposition of the sandwiched PMAA layer and the meso-pores in the silica shell-layer (mSiO2) were simultaneously afforded by pyrolysis of the pore directing agent. The structure of the rattle-type microspheres can be facilely tuned by adjusting the size of the corresponding layers in the complex multilayer architecture with the silica inner core as an example. Further, these rattle-type microspheres with functional inner cores exhibited unique and novel properties with potential applications. As a result, the Au/mSiO2 rattle-type microspheres revealed a good catalytic performance towards the reduction of nitrophenol. The surface engineering of magnetic iron oxide/mSiO2 (MIO@mSiO2) rattle type microspheres was performed for grafting functional biocompatible poly(ethylene glycol) (PEG) and tumor targeting agent folic acid (FA) through a silica coupling reaction. The multifunctional rattle-type microspheres were used as a drug carrier with a controlled release property.