Graphene oxide-decorated Fe<Subscript>2</Subscript>(MoO<Subscript>4</Subscript>)<Subscript>3</Subscript> microflowers as a promising anode for lithium and sodium storage

Mixed transition metal oxides (MTMOs) have received intensive attention as promising anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). In this work, we demonstrate a facile one-step water-bath method for the preparation of graphene oxide (GO) decorated Fe₂(MoO₄)₃ (FMO) microflower composite (FMO/GO), in which the FMO is constructed by numerous nanosheets. The resulting FMO/GO exhibits excellent electrochemical performances in both LIBs and SIBs. As the anode material for LIBs, the FMO/GO delivers a high capacity of 1,220 mAh·g^–1 at 200 mA·g^–1 after 50 cycles and a capacity of 685 mAh·g^–1 at a high current density of 10 A·g^–1. As the anode material for SIBs, the FMO/GO shows an initial discharge capacity of 571 mAh·g^–1 at 100 mA·g^–1, maintaining a discharge capacity of 307 mAh·g^–1 after 100 cycles. The promising performance is attributed to the good electrical transport from the intimate contact between FMO and graphene oxide. This work indicates that the FMO/GO composite is a promising anode for high-performance lithium and sodium storage.

Open image in new window

     

卷积积分和拉普拉斯变换在一阶电路中的应用

电路的任意激励的零状态响应,可以用卷积积分和拉普拉斯交换的方法求解。本文通过两个一阶电路的实例,阐述了两种方法的应用特点。     

Evaluation of Landsat 8 OLI imagery for unsupervised inland water extraction

The successful launch of the Landsat 8 satellite continues the Earth observation of the Landsat series, which has been taking place for nearly 40 years. With the increase in the band number and the improved spectral range compared with the previous Landsat imagery, it will be possible to expand the application of the new Landsat 8 imagery. The purpose of this study is to explore water extraction based on the new Landsat 8 Operational Land Imager (OLI) imagery. According to the specific inland water conditions (clear water, turbid water, and eutrophic water), a number of highly adaptable water indices are assessed for water extraction using Landsat OLI imagery. The results show that clear water is the easiest to extract among the different types of waterbodies, with the highest average accuracy of 97%. The highest-accuracy methods are the automated water extraction index for shadow pixels (AWEI_sh), the normalized difference water index using bands 4 and 7 (NDWI₄₇), and the normalized difference water index using bands 3 and 7 (NDWI₃₇), with accuracies of 98.55%, 95.50%, and 96.61%, corresponding to clear water, turbid water, and eutrophic water, respectively. Through the analysis of the different methods for optimal band selection, the seventh band OLI7 (shortwave infrared 2, SWIR-2) of Landsat OLI shows the best performance in water identification. When applying the water indices to water extraction, Otsu’s algorithm has been used to automatically select the water threshold. Using extensive experiments with Otsu’s algorithm and a manual method, it was found that Otsu’s algorithm can replace manual selection and has the ability to select an accurate threshold for water extraction.     

Reversible data hiding in encrypted images based on multi-level encryption and block histogram modification

Multimedia Tools and Applications - In recent years there has been significant interest in reversible data hiding, and also in particular, reversible data hiding in encrypted images (RDH-EI). This...     

基于工作任务的“4-5-6”情景化项目驱动教学模式的设计与实践

目前我国高职教育正处于改革的重要阶段,创新课程的教学模式,是高职教育的要求,也是课程建设与职业岗位有效接轨的要求。基于工作任务的"4-5-6"情景化项目驱动教学模式,是以职业能力培养为目标,围绕"岗位工作任务"这一主题,以"4"个阶段来划分能力培养过程,以"5"化教学作为教学设计,以"6"个步骤作为教学实施的教学法。通过在Linux操作系统课程教学中的改革实践表明,该教学模式培养了学生的自我学习能力和创造力,提高了学生的职业能力。     

Design and application of a new series of gallbladder endoscopes that facilitate gallstone removal without gallbladder excision

In recent years, some Chinese doctors have proposed a new concept, gallstone removal without gallbladder excision, along with transition of the medical model. As there is no specialized endoscope for gallstone removal without gallbladder excision, we designed and produced a new series of gallbladder endoscopes and accessories that have already been given a Chinese invention patent (No. ZL200810199041.2). The design of these gallbladder endoscopes was based on the anatomy and physiology of the gallbladder, characteristics of gallbladder disease, ergonomics, and industrial design. This series of gallbladder endoscopes underwent clinical trials in two hospitals appointed by the State Administration of Traditional Chinese Medicine. The clinical trials showed that surgeries of gallstones, gallbladder polyps, and cystic duct calculus could be smoothly performed with these products. In summary, this series of gallbladder endoscopes is safe, reliable, and effective for gallstone removal without gallbladder excision. This note comprehensively introduces the research and design of this series of gallbladder endoscopes.     

Wafer-level multilayer integration of RF passives with thick BCB/metal interlayer connection in silicon-based SiP

This paper presents an integration technology for RF passives using benzocyclobutene (BCB)/metal multilayer interconnection for system-in-package applications. This technology has been specially developed for RF subsystem packages in which a thick polymer, BCB (more than 15 μm thick), is adopted as dielectric with lossy silicon as substrate for its excellent characteristics. Both dry-etch BCB and photosensitive BCB are applied in this work, and their processes are briefly introduced and compared. An RF power divider, an MIM capacitor, different types of RF inductors as well as a coupled microstrip based band-pass filter are fabricated and measured at wafer level. The results show good electrical performances, and accordingly the passives are well applicable in RF band. Moreover, the subsystem models including monolithic chips connected with passives are presented.     

协合型增稠剂的流变性及其应用性能的研究

本文采用Brookfield RVT型旋转粘度计进行粘度测定,研究协合协增稠剂的流变性,将粘度数据进行计算机处理,回归出Casson方程,获得屈服值和无穷大剪切粘度,以描述增稠体系的遮盖力、稳定性、流平和流挂、沉降等性质,并对耐电解质性和后增稠进行了测试。本方法通过对粘度的测定,提供了一种对增稠剂的应用性能进行综合评价的途径。     

水性木器装修清漆的研制

以水性聚氨酯分散体与丙烯酸乳液及其混合液为成膜物 ,选用几种合适的助剂 ,研制出性能价格比良好的水性木器装修清漆。