Formation and microstructural characterization of whey protein isolate/beet pectin coacervations by laccase catalyzed cross-linking

The purpose of this study was to characterize the properties of stable and reinforced protein–polysaccharides complex coacervations firstly formed by electrostatic interaction between WPI and beet pectin, and followed by laccase cross-linking through ferulic acid present in beet pectin. The interaction of whey protein isolate (WPI, 6 g/100 ml) with beet pectin (0–0.16 g/100 ml) in aqueous solutions was studied at different pH (3–7). ζ-potential and light-scattering techniques were used to provide information about the electrical charge and aggregation of individual biopolymers and complex coacervations. Stable WPI/beet pectin complex coacervations were formed when system consisted of 6 g/100 ml WPI and 1 g/100 ml beet pectin at pH 3.5. The microstructure and viscoelastic properties of WPI and beet pectin complex coacervations in the presence of laccase (0, 100, 300 U) was also studied using FT-IR, rheology, and confocal laser scanning microscopy (CLSM) techniques. The results obtained clearly showed that laccase catalyzed cross-linking of ferulic acid present in beet pectin had a remarkable influence on the physical properties of WPI–beet pectin complex coacervations microstructure. The reinforced complex coacervations formed fine networking structures which may provide convenient means for food industry to incorporate bioactive components into food products.     

开挖条件下路基边坡的时效稳定分析

针对开挖条件下路基边坡变形的时效特点,依据Mohr-Coulomb塑性屈服理论,建立了黏弹塑性流变模型,并通过理论推导,得出了模型的本构方程式。结合工程算例,其计算结果显示:在路基边坡坡面浅层范围、坡脚位置及坡顶局部范围,安全系数变化大,并随着时间的延续安全系数逐渐减小。该结果能为判断路基边坡时效是否稳定提供依据。     

Experimental study of oscillation behaviors in confined impinging jets reactor under excitation

Dynamic behaviors in a three‐dimensional confined impinging jets reactor (CIJR) under excitation were experimentally studied by a flow visualization technique at 75 ≤ Re ≤ 150. The effects of inlet Reynolds numbers (Re), excitation frequencies and excitation amplitudes on the oscillation behaviors in CIJR have been investigated by a particle image velocimetry (PIV) and a high‐speed camera. Results indicate that the excitation in the inflow of the opposed jets can induce periodic oscillation of the impingement plane along the axis, whose oscillation frequency is equal to the excitation frequency. At Re ≤ 100, the induced axial oscillation can further cause a deflective oscillation with a frequency nearly equal to the excitation, and the scale of the vortex in the impingement plane is well regulated by the excitation frequency. At Re = 150, the excitation of amplitude less than 20% has insignificant effect on the deflective oscillation existing in CIJR. A semiempirical formula has been proposed to predict the oscillation amplitude of the impingement plane in CIJR under excitation. © 2014 American Institute of Chemical Engineers AIChE J, 61: 333–341, 2015     

低能量沥青温拌技术的应用与实践

低能量沥青温拌技术作为沥青混合料泡沫温拌技术的一种,其生产、施工过程中不需要添加任何温拌剂,因没有温拌剂生产过程的能耗与排放,系统能耗更低,并且在节约成本方面具有明显优势,这使得低能量沥青温拌技术迅猛发展,成为当前世界各国最感兴趣的温拌技术之一。笔者通过其与热拌沥青混合料的对比,介绍了低能量沥青温拌技术在欧洲的应用和实践,提出了低能量沥青温拌技术推广应用需要解决的关键性问题。     

Joining different metallic sheets without protrusion by flat hole clinching process

In this paper, we propose an architecture based on an artificial neural network (ANN), to learn welding skills automatically in industrial robots. With the aid of an optic camera and a laser-based sensor, the bead geometry (width and height) is measured. We propose a real-time computer vision algorithm to extract training patterns in order to acquire knowledge to later predict specific geometries. The proposal is implemented and tested in an industrial KUKA KR16 robot and a GMAW type machine within a manufacturing cell. Several data analysis are described as well as off-line and on-line training, learning strategies, and testing experimentation. It is demonstrated during our experiments that, after learning the skill, the robot is able to produce the requested bead geometry even without any knowledge about the welding parameters such as arc voltage and current. We implemented an on-line learning test, where the whole experiments and learning process take only about 4 min. Using this knowledge later, we obtained up to 95 % accuracy in prediction.     

动态场景下移动机器人视觉SLAM

为实现动态场景下移动机器人自主定位和建图,解决传统视觉里程计方法跟踪效果差及累积误差问题,提升闭环检测的准确性和鲁棒性,提出融合深度学习的同时定位与地图构建方法。采用四叉树算法均匀化特征分布,解决动态场景特征聚集问题;通过优化的目标检测网络识别场景动态语义信息,剔除动态物体对位姿估计的干扰;充分提取场景空间结构信息,结合点特征和线特征实现位姿跟踪及回环检测,构建全局一致的环境地图。TUM数据集和真实场景实验结果表明：改进方法提升了移动机器人定位和建图的准确性和鲁棒性。     

电动车中超级电容控制器的设计

从硬件的拓扑图着手分析超级电容控制器的具体控制方案,以及升压变换器和降压变换器的工作原理,根据控制结构利用相关的硬件资源,选择使用了DSP(TMS320LF2407)器件,并编制了相关的软件程序.     

Synthetic curli enables efficient microbial electrocatalysis with stainless-steel electrode

Microbial electrocatalysis systems (MES) provide a cutting-edge solution to global problems associated with the environment and energy, but practical applications are hindered by the expensive electrode materials. Although stainless steel (SS) has been proposed as a promising inexpensive candidate, poor cell/SS interaction results in a low performance for MES. Here, a new synthetic biology approach was established for reinforcing the cell/SS interaction. Hybridized curli nanofibers fused with a metal-binding domain were heterogeneously expressed onto the cell surface, which realized efficient cell binding with the SS electrode. Consequently, it enabled a ~420-fold improvement of the anodic power output and a substantial enhancement of the cathodic Coulombic efficiency (from 0.6 to 4% to over 80%) with an SS electrode. This work demonstrates low-cost MES with an SS electrode and introduces a new avenue to engineer the cell/electrode interaction, which is promising for future practical applications of MES.