Metal-organic-framework-derived In2O3 microcolumnar structures embedded with Pt nanoparticles for NO2 detection near room temperature

A novel synthesis of In₂O₃ porous microcolumnar structures (MCs) by a self-sacrificial template route was carried out using MIL-68. Using a modified calcination strategy, the samples could maintain the original metal organic frame work (MOF) morphology with a high gas accessibility after a slow decomposition of organic ligands. Pt nanoparticles (NPs) were loaded on the samples before or after the MOF calcination, leading to different contact states of the Pt NPs and In₂O₃ matrix. The gas sensing properties of the samples were systematically investigated using a dynamic testing system. Particularly, sample Pt/In₂O₃ MCs-1 exhibited a superior NO₂ sensing performance near room temperature (R_g/R_a?=?44.9?at 1 part-per-million and 5.2?at 100 parts-per-billion (ppb)). The sensor resistance could recover to its baseline even at 40?°C after purging with air without any additional treatment. This can be attributed to the chemical sensitisation of the Pt NPs as well as large contents of pores and channels for gas diffusion. The introduction of humidity in the gas mixture could remarkably decrease the sensor response and recovery times owing to the ‘wet’ NO₂ adsorption mechanism. This study demonstrated a novel synthesis route of Pt-loaded In₂O₃ porous columnar structures and its potential applications in near-room-temperature detection of ppb-level NO₂.     

Systematic design space exploration using a template-based ontological method

The realization of complex engineered systems using models that are typically incomplete, inaccurate and not of equal fidelity requires the understanding and prediction of process behavior in design. This necessitates the need for extending designer’s abilities in making design decisions that are robust, flexible and modifiable particularly in the early stages of design. To address this requirement, we propose in this paper, an ontology for design space exploration and a template-based ontological method that supports systematic design space exploration ensuring the determination of the right combination of design information that meets the different goals and requirements set for a process chain. Using the proposed method, a designer is able to (1) systematically adjust the design space in due time to manage the risks of errors accumulating and propagating during the design of different stages of the process chain, (2) improve the ability to communicate and understand the interactions between design information in the process chain. We achieve the said through (1) procedure for design space exploration is identified to determine the sequence of activities needed for the systematic exploration of design space under uncertainty; (2) the decision-based design information flow is archived using the design space exploration process template and represented by utilizing frame-based ontology to facilitate the management of re-usable information. We demonstrate the efficacy of this template-based ontological method for design space exploration by carrying out the design of a multi-stage hot rod rolling system in steel manufacturing process chain.     

Hierarchically structured Mg–Al mixed metal oxides templated from pine sawdust: fabrication,Congo red adsorption and antibacterial properties

ABSTRACT

Biomorphic Mg–Al layered double hydroxides (LDHs) templated from pine sawdust as precursors, hierarchically structured Mg–Al mixed metal oxides (MMOs) with well-developed porosity were prepared through biological template method and hydrothermal process. As-synthesized composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and nitrogen adsorption measurements. Adsorption conditions including different Congo red concentration, contact time, pH and temperature were investigated. Antibacterial ability and mechanism against Escherichia coli and Staphylococcus aureus were analyzed. MMOs exhibited higher adsorption and stronger antibacterial ability as compared with biomorphic LDHs. The concept provides new insight into design and preparation efficient adsorption and antibacterial materials.     

模板混合提升方法在电梯井施工中的使用

主要介绍了金属提升吊架支模和整体滑模提升以及将两者相结合使用的具体做法及优点,电梯井施工实践证明:这种混合模板提升方法能够缩短工期,节约工程费用,提高工程效益。     

Multifunctional Nanochemistry: Ambient,Electroless, Template-Based Synthesis and Characterization of Segmented Bimetallic Pd/Au and Pd/Pt Nanowires as High-Performance Electrocatalysts and Nanomotors

Segmented noble-metal nanowires (NWs) represent an exciting, multifunctional, one-dimensional, structural architecture with a variety of potential applications. However, the widespread use of electrodeposition in the preparation of these systems has limited their potential to be produced on a large scale, since this protocol is costly and requires complex processes and caustic reaction media. Given the inherent limitations of electrodeposition, we report, for the first time, an ambient, surfactantless, template-based approach that is not only sustainable but also efficient for the reliable production of Pd/Pt and Pd/Au segmented NWs, possessing two spatially separated, chemically distinctive, but elementally pure, axial subunits. Our simple two-step synthetic approach allows for direct and predictable control over the relative segment lengths in these nanomaterials. Moreover, thorough structural characterization of these as-prepared samples confirms that our segmented NWs maintain high-quality, crystalline, elementally pure subunits with a well-defined interface between the constituent metals. In the context of preparing segmented NWs as multifunctional nanostructures, we demonstrate that these as-prepared NWs achieve high levels of performance when employed as both electrocatalysts and nanomotors.     

基于工作流的总体研制流程跟踪管理系统设计

为了满足高密度发射下总体设计研制进程管理的需求,提出并实现了基于工作流技术的总体研制流程跟踪管理系统,协同总体各专业对多任务进行设计,固化了研制流程模板知识库管理,解决了发射任务六大里程碑管理,通过与AVIDM系统计划管理模块和文档管理模块的集成,实现了对整个研制任务所有步骤进行统一跟踪、统一下发到AVIDM项目管理,最终完成研制任务的闭环管理,确保研制进度受控,减少研制风险。     

自适应连续多级分区与初始阈值估计的快速模板匹配方法

归一化互相关测度在光照改变时比采用绝对差之和测度（SAD）要稳定，但是归一化互相关测度的缺陷在于它的计算量非常大。为此，提出了一种结合自适应连续多级分区和初始阈值估计的基于归一化互相关（NCC）的快速模板匹配算法。根据模板图像中不同模块的梯度值，将模板图像进行逐级分区，通过分区顺序将互相关之和分为不同的层，得到各层互相关的上界，运用柯西-施不等式得到上界间的关系，形成自适应连续多级分区淘汰方法。同时，为了加快匹配速度，利用初始阈值估计产生一个较大的边界阈值，以淘汰初始搜索时的大量非匹配点，减少搜索点数目。实验结果表明:所提出的算法具有较好的鲁棒性，且算法的执行速度优于传统算法。     

钢筋桁架楼承板在现浇混凝土结构中的应用

主要阐述了钢筋桁架楼承板在现浇混凝土结构应用过程中的施工要点以及难点,指出采用钢筋桁架与镀锌底板结合的模式替代模板和部分钢筋,省去了全部的模板和部分方木的使用,既节约了大量劳动力,又保护了环境,具有较为深远的社会和经济意义。     

Size‐Controlled Soft‐Template Synthesis of Carbon Nanodots toward Versatile Photoactive Materials

Size‐controlled soft‐template synthesis of carbon nanodots (CNDs) as novel photoactive materials is reported. The size of the CNDs can be controlled by regulating the amount of an emulsifier. As the size increases, the CNDs exhibit blue‐shifted photoluminescence (PL) or so‐called an inverse PL shift. Using time‐correlated single photon counting, ultraviolet photoelectron spectroscopy, and low‐temperature PL measurements, it is revealed that the CNDs are composed of sp² clusters with certain energy gaps and their oleylamine ligands act as auxochromes to reduce the energy gaps. This insight can provide a plausible explanation on the origin of the inverse PL shift which has been debatable over a past decade. To explore the potential of the CNDs as photoactive materials, several prototypes of CND‐based optoelectronic devices, including multicolored light‐emitting diodes and air‐stable organic solar cells, are demonstrated. This study could shed light on future applications of the CNDs and further expedite the development of other related fields.