Fast Li+ Transport via Silica Network-Driven Nanochannels in Ionomer-in-Framework for Lithium Metal Batteries

For the development of all-solid-state lithium metal batteries (LMBs), a high-porous silica aerogel (SA)-reinforced single-Li⁺ conducting nanocomposite polymer electrolyte (NPE) is prepared via two-step selective functionalization. The mesoporous SA is introduced as a mechanical framework for NPE as well as a channel for fast lithium cation migration. Two types of monomers containing weak-binding imide anions and Li⁺ cations are synthesized and used to prepare NPEs, where these monomers are grafted in SA to produce SA-based NPEs (SANPEs) as ionomer-in-framework. This hybrid SANPE exhibits high ionic conductivities (≈10⁻³ S cm⁻¹), high modulus (≈10⁵ Pa), high lithium transference number (0.84), and wide electrochemical window (>4.8 V). The resultant SANPE in the lithium symmetric cell possesses long-term cyclic stability without short-circuiting over 800 h under 0.2 mA cm⁻². Furthermore, the LiFePO₄|SANPE|Li solid-state batteries present a high discharge capacity of 167 mAh g⁻¹ at 0.1 C, good rate capability up to 1 C, wide operating temperatures (from −10 to 40 °C), and a stable cycling performance with 97% capacity retention and 100% coulombic efficiency after 75 cycles at 1 C and 25 °C. The SANPE demonstrates a new design principle for solid-state electrolytes, allowing for a perfect complex between inorganic silica and organic polymer, for high-energy-density LMBs.     

激光条纹图像处理算法的研究

概述了数字图像处理的基本理论知识以及发展趋势,介绍了三维人体激光条纹图像的特点,并重点讲述了所选取的图像处理算法及其实现过程,对非接触式三维人体尺寸的获取有一定的参考意义。     

Effects of microstructure and strength on wear performance in rough milling of austempered ductile iron

The machinability of various grades of austempered ductile iron (ADI) has been investigated for rough milling operations. ADI 900, ADI 1050 and ADI 1200 grades were commercially produced, commercially heat treated and machined under controlled conditions using coated carbide inserts with coolant in the laboratory. The milling performance of the various grades was compared to that of AISI/SAE 4340 with similar hardness. In this study, machinability characteristics relative to wear rate (ISO 8688-2) and machining forces were measured and related to initial microstructure and properties. These preliminary results have been used to establish initial rough milling machining guidelines for machining ADI with coated carbide milling inserts.     

Efficient CAD-based triangulation of unordered 3D data

Abstract. The paper proposes a new method for efficient triangulation of large, unordered sets of 3D points using a CAD model comprising NURBS entities. It is primarily aimed at engineering applications involving analysis and visualisation of measured data, such as inspection, where a model of the object in question is available. Registration of the data to the model is the necessary first step, enabling the triangulation to be efficiently performed in 2D, on the projections of the measured points onto the model entities. The derived connectivity is then applied to the original 3D data. Improvement of the generated 3D mesh is often necessary, involving mesh smoothing, constraint-based elimination of redundant triangles and merging of mesh patches. Examples involving random measurements on aerospace and automotive free-form components are presented. Received: 30 August 1999 / Accepted: 10 January 2000     

Adaptive wire bow-tie antenna for GPR applications

In this paper, the basic design of an adaptive ground penetrating radar antenna is introduced. The antenna is able to adapt its input impedance to a variation in the antenna elevation and soil type to keep reflections at the antenna's terminal minimum. As a result, energy transfer from the generator to the antenna is maximized, which in turn maximizes the energy radiated by the antenna into the ground for different antenna elevations and soil types. The antenna is based on a wire bow-tie structure with variable flare angle for adjusting the antenna's input impedance. The flare angle variation is realized by short-circuiting the gaps separating the wires from the feed point of the antenna, for which electronic switching devices such as PIN diodes could be used to allow fast and convenient control of the antenna's flare angle.     

Analysis and Design of Improved Antennas for GPR

In this paper a concept of adaptive antennas for ground penetrating radar is introduced. It is demonstrated that antenna adaptation with respect to the antenna feed-point reflection can be achieved for different ground types. This adaptation can be realized using a wire bow-tie antenna with variable flare angle. By varying the flare angle, a minimal feed-point reflection can be obtained for different types of ground. Moreover, the shape and size of the footprint of the bow-tie antenna can be adjusted by changing the flare angle for improving detection/imaging. Furthermore, a novel loading scheme based on a combination of a capacitive and resistive loading is introduced, and applied on a solid bow-tie antenna. It is shown that using this loading scheme an efficient ultra-wideband antenna for ground penetrating radar applications can be realized.     

Catalytic Deoxygenation of Stearic Acid and Palmitic Acid in Semibatch Mode

The deoxygenation experiments of different reactants, i.e., pure palmitic acid, stearic acid, and a technical grade stearic acid containing a mixture of 59% of palmitic and 40% of stearic acid were successfully performed over 4 wt% Pd/C mesoporous catalyst at 300 °C under 17 bar of 5% H₂ in argon. The main product in catalytic deoxygenation of saturated fatty acids, C16 and C18, were aliphatic chain length hydrocarbons containing one less carbon than the corresponding acid. Additionally it was found that the deoxygenation rates of different reactant were independent on carbon chain length of its fatty acids.     

Tailoring cotton fabric with wettability gradient and anisotropic penetration of liquid by spray coating

Abstract

Comfort has been one of the most important features of clothing, particularly for sportswear, which requires an effective transport of heat and moisture from the inner to the outer side of clothing. We herein report the use of a simple technique of spray coating and commercially available water repellents for a one-sided hydrophobic and self-initiated one-way water transport cotton fabric. The highlight of this work is the simplicity of the process and choice of chemicals that can be adopted easily by any textile finishing industry. On this fabric, water was able to diffuse and penetrate the fabric structure in one direction from the hydrophobic to the hydrophilic side but was unable to go the opposite direction. The directional transport improved with smaller droplets and lower add-on achievable by higher air pressure and longer distance of spray coating. From moisture management tests, the best result was obtained with the spray coating of Phobol NB-NH at an air pressure of 3.0?kgf/cm² and a distance of 120?cm. Phobol NB-NH gave better result of transport and overall comfort properties than Phobotex RSY.     

Green isolation and physical modification of pineapple stem waste starch as pharmaceutical excipient

The waste of inedible parts of pineapple, particularly in tropical countries, contributes to environmental burden. This study aimed to utilize pineapple stem waste as a source of starch-based pharmaceutical excipient. The starch was isolated from pineapple stem waste using a simple process without applying harsh chemicals. The isolated starch (PSS) was then physically modified through gelatinization and spray drying to improve its physical properties. Starch characteristics were identified by FTIR, TGA, and XRD analysis. The SEM imaging showed morphological change with reduced surface roughness due to physical modification of the starch. Decreased crystallinity of modified starch (MPS) was confirmed by our XRD results: the peaks of A-type crystalline at 2θ of 13°, 15°, 18°, and 23° were present in PSS, yet mostly absent in MPS. Thermogravimetric analysis showed that MPS behaved differently from PSS and the degradation events occurred at lower temperature. When the starch was spray-dried without prior gelatinization process, the physicochemical characteristics of spray-dried starch resembled untreated starch. Moisture content in PSS (10.66%) decreased after gelatinization to 7.3%. Potential use of MPS was demonstrated by its powder flowability (Student’s t test, p?<?0.05), swelling capacity (Student’s t test, p?<?0.05), and compaction profile. In summary, our findings demonstrated that modified pineapple starch showed better physical characteristics and quite promising as a tablet binder and disintegrant.