存在再生料层的大修路面构造优化设计探究

阐述介绍存在再生料层的路面构造设计控制指标及主要设计参数,分析探究存在再生料层的大修路面典型构造,给出存在冷再生料层的大修路面典型构造优化设计推荐参数值,对存在再生料层的路面构造设计具有工程应用和技术参考价值。

大型电熔炉停产保温操作的注意事项

阐述了电熔炉在停产保温期间,停产前后、保温送电、恢复生产等环节的保温操作,为了保证料质、不影响熔炉寿命,强调停产保温期间要保证炉内的玻璃液不能硬化,值班操作人员要遵守操作规范。

In Situ Growth of 3D Hierarchical ZnO@Ni_xCo_(1-x)(OH)_y Core/Shell Nanowire/Nanosheet Arrays on Ni Foam for High-Performance Aqueous Hybrid Supercapacitors

In this study, we designed and synthesized a novel battery-type electrode featuring three-dimensional(3D) hierarchical ZnO@Ni_xCo_(1-x)(OH)_y core/shell nanowire/nanosheet arrays arranged on Nifoam substrate via a two-step protocol including a wet chemical process followed by electro-deposition. We then characterized its composition, structure and surface morphology by X-ray diff raction, energy-dispersive X-ray spectrometry(EDS), X-ray photoelectron spectroscopy, scanning electron microscopy(SEM), transmission electron microscopy, EDS elemental mapping. Our electrochemical measurements show that the ZnO@Ni_(0.67)Co_(0.33)(OH)_y electrode material exhibited a noticeably high specific capacity of as much as 255(mA ·h)/g at 1 A/g. Additionally, it demonstrated a superior rate capability, as well as an excellent cycling stability with 81.6% capacity retention over 2000 cycles at 5 A/g. This sample delivered a high energy density of 64 W·h/kg and a power density of 250 W/kg at a current density of 1 A/g. With such remarkable electrochemical properties, we expect the 3D hierarchical hybrid electrode material presented in this work to have promising applications for the next generation of energy storage systems.

Formation mechanism and growth kinetics of TiAl_(3) phase in cold-rolled Ti/Al laminated composites during annealing

Cold-rolled Ti/Al laminated composites were annealed at 525−625℃for 0−128 h,and the interfacial microstructure evolution was investigated.The results indicate that only the TiAl_(3) phase was formed at the Ti/Al interface;most of TiAl_(3) grains were fine equiaxed with average sizes ranging from hundreds of nanometers to several microns and the TiAl_(3) grain size increased with increasing annealing time and/or temperature,but the effect of annealing temperature on the TiAl_(3) grain size was far greater than that of annealing time.The growth of the TiAl_(3) phase consisted of two stages.The initial stage was governed by chemical reaction with a reaction activation energy of 195.75 kJ/mol,and the reaction rate constant of the TiAl_(3) phase was larger as the Ti/Al interface was bonded with fresh surfaces.At the second stage,the growth was governed by diffusion,the diffusion activation energy was 33.69 kJ/mol,and the diffusion growth rate constant of the TiAl_(3) phase was mainly determined by the grain boundary diffusion owing to the smaller TiAl_(3) grain size.

Preparation and Research of a Bionic Woven Tracheal Stent with Horizontal Pipeline

The paper designed a bionic woven tracheal stent and the stent was a multi-layer tubular structure with a transverse pipeline.Polydioxanone( PDO) monofilament and β-hydroxybutyrate and β-hydroxyvalerate copolymers/polylactic( PHBV/PLA) multifilament were chosen as the tissue engineering tracheal stent materials,and chitosan was chosen as the coating material. This study selected appropriate basic fabric structures and prepared the tracheal stent by setting reasonable weaving parameters,then treated the sample with coating and heat setting. Radical compression performances of the horizontal pipeline and longitudinal pipeline of this tracheal stent were investigated,and the experimental results showed that the stent had good performance on radial supporting force and elastic recovery,which meant it could supply adequate supports for cell growth and tissue regeneration of tracheal lesions; the horizontal pipeline could provide a good experimental foundation for reconstruction of the cartilage ring.

Deformation Characteristics of Leather for Shoe Upper, Filled with Natural Minerals

A promising direction in the tanning industry is the use of natural minerals as environmentally friendly technologically efficient materials that are able to adjust and regulate the efficiency of formation of the dermis structure and the properties of finished leather. The use of finely-dispersed minerals promotes alignment of topographic areas in thickness, increases the yield of leather on the area by avoiding bonding structural elements of the dermis. Changes in the microstructure of the dermis, as a result of mineral filling, contribute to improvement of performance and hygienic properties of finished leather. And the study of the properties of the specified skins should be consistent with the features of operations on their cutting, shoe molding and shoe upper fixing preparations. The most important properties of leather materials, which largely determine the quality of basic technological operations of shoe manufacturing are the deformation properties. Lack of information about relaxation and deformation properties of the leather produced by the new technologies do not allow to predict their ability to form shapes and save it--indicates the relevance of this study. This paper analyzes relaxation and deformation characteristics of natural leather for shoe uppers, filled with natural minerals montmorillonite and zeolite, and the ability to predict their formation and preservation of shape in service. Features of deformation of the skin with mineral content were assessed by determining single-cycle characteristics when attaching to a complete test cycle ＂loading-unloading-rest＂ sample. Correlations of elastic and plastic （permanent） deformation have been established, kinetics of changes in linear characteristics of the samples after removal of the load has been investigated. Introduction of dispersions of mineral to the structure of the dermis contributes to the strength of semi-finished leather, increase of the uniformity of mechanical properties in the longitudinal and transverse directions and rise of shape stability index. It is shown that the direction of this study allows us to offer new competitive ecologically friendly materials to produce shoes.

Epitaxially grown monolayer VSe2： an air-stable magnetic two-dimensional material with low work function at edges

Recent experimental breakthroughs open up new opportunities for magnetism in few-atomic-layer twodimensional(2 D) materials, which makes fabrication of new magnetic 2 D materials a fascinating issue.Here, we report the growth of monolayer VSe_2 by molecular beam epitaxy(MBE) method. Electronic properties measurements by scanning tunneling spectroscopy(STS) method revealed that the asgrown monolayer VSe_2 has magnetic characteristic peaks in its electronic density of states and a lower work-function at its edges. Moreover, air exposure experiments show air-stability of the monolayer VSe_2. This high-quality monolayer VSe_2, a very air-inert 2 D material with magnetism and low edge work function, is promising for applications in developing next-generation low power-consumption, high efficiency spintronic devices and new electrocatalysts.

Te-seeded growth of few-quintuple layer Bi2Te3 nanoplates

We report on a Te-seeded epitaxial growth of ultrathin Bi2Te3 nanoplates （down to three quintuple layers （QL）） with large planar sizes （up to tens of micrometers） through vapor transport. Optical contrast has been systematically investigated for the as-grown Bi2Te3 nanoplates on the SiO2/Si substrates, experimentally and computationally. The high and distinct optical contrast provides a fast and convenient method for the thickness determination of few-QL Bi2Te3 nanoplates. By aberration-corrected scanning transmission electron microscopy, a hexagonal crystalline structure has been identified for the Te seeds, which form naturally during the growth process and initiate an epitaxial growth of the rhombohedral- structured Bi2Te3 nanoplates. The epitaxial relationship between Te and Bi2T% is identified to be perfect along both in-plane and out-of-plane directions of the layered nanoplate. Similar growth mechanism might be expected for other bismuth chalcogenide layered materials.

Selective Growth of ZnO Nanorods on SiO2/Si Substrates Using a Graphene Buffer Layer

A promising strategy for the selective growth of ZnO nanorods on SiO2/Si substrates using a graphene buffer layer in a low temperature solution process is described. High densities of ZnO nanorods were grown over a large area and most ZnO nanorods were vertically well-aligned on graphene. Furthermore, selective growth of ZnO nanorods on graphene was realized by applying a simple mechanical treatment, since ZnO nanorods formed on graphene are mechanically stable on an atomic level. These results were confirmed by first principles calculations which showed that the ZnO-graphene binding has a low destabilization energy. In addition, it was found that ZnO nanorods grown on SiO2/Si with a graphene buffer layer have better optical properties than ZnO nanorods grown on bare SiO2/Si. The nanostructured ZnO-graphene materials have promising applications in future flexible electronic and optical devices.

Dual-metal precursors for the universal growth of non-layered 2D transition metal chalcogenides with ordered cation vacancies

Two-dimensional(2D)transition metal chalcogenides(TMCs)are promising for nanoelectronics and energy applications.Among them,the emerging non-layered TMCs are unique due to their unsaturated dangling bonds on the surface and strong intralayer and interlayer bonding.However,the synthesis of non-layered 2D TMCs is challenging and this has made it difficult to study their structures and properties at thin thickness limit.Here,we develop a universal dual-metal precursors method to grow non-layered TMCs in which a mixture of a metal and its chloride serves as the metal source.Taking hexagonal Fe_(1-x)S as an example,the thickness of the Fe_(1-x)S flakes is down to 3 nm with a lateral size of over 100 μm.Importantly,we find ordered cation Fe vacancies in Fe_(1-x)S,which is distinct from layered TMCs like MoS_(2) where anion vacancies are commonly observed.Low-temperature transport measurements and theoretical calculations show that 2D Fe_(1-x)S is a stable semiconductor with a narrow bandgap of60 meV.In addition to Fe_(1-x)S,the method is universal in growing various non-layered 2D TMCs containing ordered cation vacancies,including Fe_(1-x)Se,Co_(1-x)S,Cr_(1-x)S,and V_(1-x)S.This work paves the way to grow and exploit properties of non-layered materials at 2D thickness limit.