In-situ fabrication SnO2/SnS2 heterostructure for boosting the photocatalytic degradation of pollutants

Heterostructure photocatalysts with a built-in electric field have become one of the most promising strategies to enhance photogenerated electron-hole pair separation. However, close contact between the two active components of heterogeneous photocatalysts remains a problem. Herein, the in-situ fabrication of an SnO2/SnS2 heterostructure photocatalyst was performed;the structure showed enhanced photocatalytic performance resulting from the tight-contact heterostructures. The results of photoelectrochemical measurements further verified that a tight-contact heterostructure improved the separation of photogenerated electron-hole pairs. The results of EIS Bode plots also demonstrated that such in-situ fabricated SnO2/SnS2 samples exhibited the longest carrier lifetime(41.6 μs) owing to the intimate interface of SnO2/SnS2 heterostructures.

Surface Morphology and Thermo-Electrical Energy Analysis of Polyaniline (PANI) Incorporated Cotton Fabric

With the exponential development in wearable electronics,a significant paradigm shift is observed from rigid electronics to flexible wearable devices.Polyaniline(PANI)is considered as a dominant material in this sector,as it is endowed with the optical properties of both metal and semiconductors.However,its widespread application got delineated because of its irregular rigid form,level of conductivity,and precise choice of solvents.Incorporating PANI in textile materials can generate promising functionality for wearable applications.This research work employed a straightforward in-situ chemical oxidative polymerization to synthesize PANI on Cotton fabric surfaces with varying dopant(HCl)concentrations.Pre-treatment using NaOH is implemented to improve the conductivity of the fabric surface by increasing the monomer absorption.This research explores the morphological and structural analysis employing SEM,FTIR and EDX.The surface resistivity was measured using a digital multimeter,and thermal stability is measured using TGA.Upon successful polymerization,a homogenous coating layer is observed.It is revealed that the simple pre-treatment technique significantly reduces the surface resistivity of Cotton fabric to 1.27 kΩ/cm with increasing acid concentration and thermal stability.The electro-thermal energy can also reach up to 38.2°C within 50 s with a deployed voltage of 15 V.The modified fabric is anticipated to be used in thermal regulation,supercapacitor,sensor,UV shielding,antimicrobial and other prospective functional applications.

Fabrication and analysis of TIG welding-brazing butt joints of in-situ TiB2/7050 composite and TA2

Lightweight hybrid structures of Al MMCs and titanium alloy dissimilar materials have great prospect in the defence industry application. So, it is necessary to join Al MMCs with Ti metal to achieve this structural design. In this work, in-situ Ti B_(2)/7050 composite and TA2 were firstly attempted to join by TIG welding-brazing technique. The result was that the intact welding-brazing butt joint was successfully fabricated. The joint presents dual characteristics, being a brazing on TA2 side and a welding on Ti B_(2)/7050 side. At brazing joint side, ER4043 filler metal effectively wets on TA2 under TIG heating condition,and a continuous interfacial reaction layer with 1 e3 mm is formed at welded metal/TA2 interface. The whole interfacial reaction layers are composed of Ti(Al Si)3 intermetallic compounds(IMCs), but their morphologies at the different regions present obvious distinguishes. The microhardness of the reaction layers is as much as 141 e190 HV. At welding joints side, the fusion zone appears the equixaed crystal structure, and the grain sizes are much smaller than those of welded metal, which is attributed to the effect of Ti B2 particulates from the melted Ti B_(2)/7050 on acceleration formation and inhibiting growth for the new crystal nucleus. The tensile test results show that average tensile strength of the optimal welding-brazing joint is able to achieve 138 MPa. The failure of the tensile joint occurs by quasi-cleavage pattern, and the cracks initiate from the IMCs layer at the groove surface of TA2 and propagate into the welded metal.

In-situ SEM and Stereomicroscope Study Delamination Evolution of Glass Fabric Reinforced Polycarbonate Composite

The main objective of this study is to investigate the dynamic processes of the interlaminar fracture of the glass woven fabric reinforced polycarbonate composites through in-situ observation of specimen under mode Ⅰ loading by SEM and stereomicroscope. The results show that the evolution processes of interlaminar damage consist of micro-crack initiation, growth and coalescence and advance forward of the main crack tip. The mode of crack propagation in fabric composite observed here seem to be the propagation along interface, interface change and fabric separation.

Design of wear-out-failure in-situ repair parts by environment-friendly nanocopper additive

Oleic acid surface-modified Cu nanoparticles with an average size of 20 nm were prepared by liquid phase reducing reaction. The tribological performance and mechanism of nanocopper as additive were studied by means of tribotester, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and nanoindentation instrument. The results indicate that the modified nanocopper additive can significantly improve the wear resistance and reduce friction coefficient of base oil. A copper protective film is formed and contributes to the excellent tribological properties of nanocopper additive. On the basis of the film forming mechanism, a new in-situ repair method was designed and used to repair wear-out-failure injection pump plunger and barrel. Furthermore, the current research progress of nanoparticles as green energy-saving lubricating oil additives were presented.

Revealing the vertical structure of in-situ fabricated perovskite nanocrystals films toward efficient pure red light-emitting diodes

The development of efficient perovskite light-emitting diodes(PeLEDs)relies strongly on the fabrication of perovskite films with rationally designed structures(grain size,composition,surface,etc.).Therefore,an understanding of structure-performance relationships is of vital importance for developing high-performance perovskite devices,particularly for devices with in-situ fabricated perovskite nanocrystal films.In this study,we reveal the vertical structure of an in-situ fabricated quasi-two-dimensional perovskite film.By combining time-of-flight secondary ion mass spectrometry,energy dispersive spectroscopy,grazing incidence wide-angle X-ray scattering(GIWAXS),and low-temperature photoluminescence spectra,we illustrate that the resulting in-situ fabricated DPPA_(2)Cs_(n-1)Pb_(n)(Br_(0.3)I_(0.7))_(3n+1)(DPPA^(+):3,3-diphenylpropylammonium)film has a gradient structure with a very thin layer of ligands on the surface,predominantly small-n domains at the top,and predominantly large-n domains at the bottom owing to the solubility difference of the precursors.In addition,GIWAXS measurements show that the domain of n=2 on the top layer has an ordered in-plane alignment.Based on the understanding of the film structure,we developed an in-situ fabrication process with ligand exchange to achieve efficient pure red PeLEDs at 638 nm with an average external quantum efficiency(EQE)of 7.4%.The optimized device had a maximum luminance of 623 cd/m^(2) with a peak EQE of 9.7%.

自修复织物研究进展及其医疗防护应用展望

针对纺织领域内传统织物被撕破或刺破后很难修复的问题,基于现有研究成果,对当前自修复织物的技术发展现状进行总结。介绍了自修复织物基于构成形式和自修复机理的分类,分析了自修复织物的研究进展及存在的问题,展望了自修复织物在医疗防护领域的应用趋势。认为:自修复织物不仅能够延长织物的使用寿命提高可靠性,还将为智能服装设计奠定必要的技术基础。自修复织物在医疗防护领域具有巨大的应用前景,未来可应用于医用帐篷、医用防护口罩及医用防护服等不同医疗防护装备。

Preparation and Characterization of PANI/PET Composite Conductive Fabric

Polyaniline /Polyester( PANI /PET) composite conductive fabric is prepared through in-situ polymerization process using aniline as monomer and PET fabric as matrix,which is treated with alkali deweighting and low temperature plasma. The property of PANI /PET composite conductive fabric is studied and characterized,including scanning electron microscope( SEM), infrared spectroscopy, conductivity, wash fastness and mechanical properties. The results show that the optimal polymerization conditions: the molar ratio of ammonium persulfate and aniline is1∶ 1,the concentration of sulfuric acid is 1 mol /L and reaction time is 90 min. Under optimum conditions,the surface resistivity of PANI /PET composite conductive fabric is about 170 Ω. After washed 5 times, the surface resistivity of PANI /PET composite conductive fabric is stable at 1 450 Ω. The breaking strength and breaking elongation of PANI /PET composite conductive fabric decrease compared with PET fabric.

Sulfide-Based Nickel-Plated Fabrics for Foldable Quasi-Solid-State Supercapacitors

Smart wearable market is burgeoning,and flexible energy storage is crucial to cope with its development.The commonly-used metal-based current collectors are heavy with limited flexibility.Other carbon-based current collectors are expensive and fragile.Moreover,the poor interface between active material and current collector leads to unsatisfactory stability.Herein,these two issues are attempted to be solved by using cheap and lightweight polyester-based fabrics as well as in-situ growth.A deposited thin layer of nickel on the fabrics not only enhances the conductivity,but also serves as the sacrificial precursor for the growth of active materials.Thus,intimate contact is secured via chemical bonding.The electrode with ternary(metalinorganic-organic)component shows excellent electrochemical performance.Namely,high areal capacity is realized(2.2 C cm^(-2)at 2 mA cm^(-2)),which is far superior to its rigid nickel-foam-based counterpart.Furthermore,an allsolid-state supercapacitor device was assembled.The device provides an areal capacity of 2.03 C cm^(-2)at the current density of 2 mA cm^(-2).It realizes an energy density of 0.45 mWh cm^(-2)when the power density is 1.6 mW cm^(-2).This work offers a feasible and cost-efficient way for fabricating electrode materials with excellent performance for portable supercapacitors.

Biodegradable materials for bone defect repair

Compared with non-degradable materials,biodegradable biomaterials play an increasingly important role in the repairing of severe bone defects,and have attracted extensive attention from researchers.In the treatment of bone defects,scaffolds made of biodegradable materials can provide a crawling bridge for new bone tissue in the gap and a platform for cells and growth factors to play a physiological role,which will eventually be degraded and absorbed in the body and be replaced by the new bone tissue.Traditional biodegradable materials include polymers,ceramics and metals,which have been used in bone defect repairing for many years.Although these materials have more or fewer shortcomings,they are still the cornerstone of our development of a new generation of degradable materials.With the rapid development of modern science and technology,in the 21 st century,more and more kinds of new biodegradable materials emerge in endlessly,such as new intelligent micro-nano materials and cell-based products.At the same time,there are many new fabrication technologies of improving biodegradable materials,such as modular fabrication,3 D and 4 D printing,interface reinforcement and nanotechnology.This review will introduce various kinds of biodegradable materials commonly used in bone defect repairing,especially the newly emerging materials and their fabrication technology in recent years,and look forward to the future research direction,hoping to provide researchers in the field with some inspiration and reference.

Directly electrospinning submillimeter continuous fibers on tubes to fabricate H2S detectors with fast and high response

The fast and high response detection of neurotoxic H_(2)S is of great importance for the environment.In this paper,directly electrospinning technology on the ceramic tube is developed to improve the response of H_(2)S detector based on superlong SnO_(2)fibers.The submillimeter continuous fibers are deposited directly on ceramic tubes by in-situ electrospinning method and can keep morphology of fibers during calcination.By employing this technology,CuO-doped SnO_(2)fiber H_(2)S detectors are fabricated,and 10%atom CuO-doped SnO_(2)H_(2)S detector shows the highest response of 40 toward 1 ppm H_(2)S at 150℃while the response is only 3.6 for the H_(2)S detector prepared in traditional route.In addition,the in-situ electrospinning H_(2)S detectors show faster response and recovery compared to the H_(2)S detectors fabricated by the conventional way.The high and fast response of H_(2)S detectors based on in-situ electrospinning can be ascribed to the continuous fiber structure and CuO modification.The present in-situ electrospinning technology may provide a new strategy for the development of other gasdetectors and bio-detectors with fast and high response.

钢结构梁柱节点研究现状及改进技术分析

【目的】装配式钢节点的强度对结构整体的抗震性能有重要影响,因此需要研究节点的优化形式。【方法】分析目前装配式结构梁柱节点的发展现状,提出一种可修复摩擦型耗能节点,对该节点的构造形式、工作机理和创新点进行简要阐述,通过拟静力试验得到节点荷载-位移滞回曲线,分析其抗震性能。【结果】结果表明,该节点可以将地震作用产生的损伤集中在连接区,实现核心区塑性铰外移,并且可以通过滑移板摩擦和钢质铰转动提高节点耗能能力,震后通过更换连接区滑移板实现节点修复。【结论】研究成果能够为可修复钢框架节点的设计提供一定的参考。

装配式水泥混凝土道面在机场抢修中的应用

水泥道面是国内机场应用最为广泛的道面类型,随着大量机场水泥道面进入维护期,水泥道面损坏后修复困难的问题也越来越凸显。装配式水泥混凝土道面具有“集中预制、分散安装”的特点,具有快速、环境能力适应强、经济的优点,是现有水泥道面维护的良好解决方案。现调研了国内外装配式水泥混凝土道面技术的研究现状,介绍了在浦东机场、伊春机场的成功应用案例;指出了应用在机场道面抢修的主要施工工艺和技术要求,提出了装配式水泥道面技术难点在于保证板底的充分填充、道面接缝传力的恢复和道面表面的平整度;经分析认为开发相应的专用设备、实现道面技术的工业化方可解决装配式水泥混凝土道面技术实施的难题。

预制皮瓣修复足底负重区软组织缺损

目的 探讨用预制皮瓣修复足底负重区软组织损伤缺损的效果。方法 先于拟施皮瓣移植部位切取部分全厚皮片与健侧足心区相应大小皮片互换移植、打包构成含健侧足心皮片的预制皮瓣并做延迟移植。 3周后将该皮瓣移植于患足并使足心皮片部位于足底负重部位 ,同时从足跟骨跖面钻数个骨孔至两侧面 ,由皮瓣内壁缝线于骨孔内悬吊固定。使皮瓣与骨跖面贴切牢固 ,恢复足底垂直纤维纵隔结构。结果 8例患者随访 15～ 2 3个月 ,负重行走良好 ,无溃疡 ,外形满意。根据美国 AOFAS足踝功能评分标准 :5例大于 80分 ,2例大于 75分 ,1例 70分。结论 利用健侧足心预制皮瓣可以较好地恢复足底创面 ,且耐磨、耐压 ,功能及感觉功能良好。解决一般组织瓣移植存在稳定性差 。

碳纤维布提高高强混凝土柱抗震能力评估方法

针对利用碳纤维布加固既有建筑中的高强混凝土柱,以及加固后抗震性能的评估问题,对 7根高强混凝土柱进行试验研究,分析了碳纤维布约束高强混凝土的影响因素和约束机理.通过理论推导和统计回归的方法,提出了碳纤维布加固高强混凝土柱位移延性比的理论计算方法和基于两个回归公式的简化计算方法.两种计算方法概念清晰,简便适用,分析结果与试验值的相对误差控制在 2000左右,可以满足抗震加固设计的要求.两个回归公式的决定系数R2 分别为 0. 97和 0. 99,具有很高的拟合精度,可用于碳纤维布约束混凝土柱的相关研究.

国内外焦炭塔的研究现状及其进展

介绍了国内外焦炭塔的设计、制造、操作水平的现状以及在延寿和修复技术方面的发展水平,并且通过与其他先进国家的对比,指出了我国焦炭塔研究技术的发展差距。

含氟聚倍半硅氧烷制备自修复疏水真丝织物

合成了含氟聚倍半硅氧烷(F-POSS)分子,通过轧烘焙方法将F-POSS整理到真丝织物表面,制得具有自修复疏水性能的真丝织物。探讨了F-POSS用量、聚丙烯酸酯用量、预烘/焙烘温度与时间等工艺参数对真丝织物疏水性能的影响,较佳的处理工艺条件为:F-POSS 3 g/L,聚丙烯酸酯100 g/L,80℃预烘5 min,140℃焙烘3 min。测试了整理前后真丝织物的自修复性能、耐摩擦及耐水洗色牢度、物理性能,自修复疏水真丝织物的疏水性能被破坏后自修复性能较好,织物经摩擦后,表面破损和低表面能物质部分损失,对疏水性能和物理性能的影响不大,且织物自修复性能耐水洗性较好。

硬组织修复用多孔钛研究进展

综述了适合用作硬组织修复用的多孔钛成型方法,并针对普通改性方法难以对多孔钛贯通的内部进行有效活化处理这一难题,提出了几种适合于多孔钛活化处理的方法,指出了多孔钛在硬组织修复中存在的问题及今后的发展方向。

甲基丙烯酸十八烷基酯疏水整理真丝织物的自修复性能

为提高真丝织物的易护理性,试验采用含有碳氢长链的疏水单体甲基丙烯酸十八烷基酯对真丝织物进行表面接枝改性,以提高其疏水性能。研究了疏水整理对真丝织物服用舒适性及力学性能的影响,及其疏水性能的自修复特性。结果表明:真丝织物经接枝改性处理后,纤维表面附着一层疏水烷基长链高聚物,赋予真丝织物优异的疏水性能,接触角达130°以上,并有较好的耐水洗性能;真丝织物经疏水处理后,透气性基本保持不变,透湿性、力学性能有所下降;氧气等离子体处理可以破坏处理织物的疏水能力;熨烫整理可使织物恢复疏水性能,说明经甲基丙烯酸十八烷基酯处理的真丝织物,其疏水性能具有优异的自修复能力。

经编网眼织物在高科技纺织品中的应用

本文简要介绍了经编网眼织物的形成、组织结构设计及性能特点。结合作者承担的项目,介绍了经编网眼织物在高科技领域的应用。文章以经编网眼织物开发为例子,阐述了经编产业技术创新的要点。