Enhanced photocatalytic degradation performance of organic contaminants by heterojunction photocatalyst BiVO4/TiO2/RGO and its compatibility on four different tetracycline antibiotics

Photocatalytic performance of four tetracycline antibiotics using BiVO₄/TiO₂/RGO composites was investigated. To make full use of catalysis, optimum preparation conditions involved RGO content, solution pH and hydrothermal temperature on the structure forming of BiVO₄/TiO₂/RGO composites were investigated. Subsequently, the obtained visible light-driven photocatalyst was used to degrade four kinds of tetracycline antibiotics involved tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC) and doxycycline (DXC) for wastewater treatment. Results showed that BiVO₄/TiO₂/RGO photocatalyst exhibited excellent photocatalytic activity and high compatibility due to the enhanced separation efficiency of photo-generated carriers with high reduction and oxidation capability. The degradation process of four kinds of tetracycline antibiotics was traced and detected through identifying intermediates produced in the reaction system. And a possible catalytic mechanism for BiVO₄/TiO₂/RGO photocatalyst was put forward based on band gap structure of BiVO₄ and TiO₂.     

电解铝废渣提锂方法研究

随着新能源汽车行业进入黄金发展期，动力锂电池行业呈爆发式增长，碳酸锂的需求量也逐年递增，含锂氟化盐的使用造成大量含锂电解铝废渣产生，如果得到合理回收利用，将有利于缓解新能源产业带来的用锂压力。重点研究了以含锂电解铝废渣和浓硫酸为原料，通过酸浸取等一系列工艺，制备电池级碳酸锂，同时副产冰晶石，并从实验原理、实验方法、工艺关键点控制、产品质量、工艺特点等方面进行了深度剖析。本工艺具有良好的社会效益、经济效益和环保效益，易于推广应用。     

Effect of kappa distribution on the damping rate of the obliquely propagating magnetosonic mode

Data from spacecrafts suggest that space plasma has an abundance of suprathermal particles which are controlled by the spectral index κ when modeled on kappa particle velocity distribution. In this paper, considering homogeneous plasma, the effect of integer values of κ on the damping rate of an obliquely propagating magnetosonic(MS) wave is studied. The frequency of the MS wave is assumed to be less than ion cyclotron frequency, i.e.,iw(28)w. Under this assumption, the dispersion relation is investigated both numerically and analytically, and it is found that the real frequency of the wave is not a sensitive function of κ, but the imaginary part of the frequency is. It is also shown that for those values of κ where a large number of resonant particles participate in wave–particle interaction, the wave is heavily damped, as expected. The possible application of the results to the solar wind is discussed.     

Development of localization system using ultrasonic sensor for an underwater robot to survey narrow environment

This paper describes a localization system for a swimming robot to survey underwater narrow environments. In that environment, external sensors cannot be set up to localize the robot position, as there are many structures and the robot moves three-dimensionally. Therefore, the position needs to be calculated only by internal sensors. In this work, a new localization method based on map-matching is proposed, referring to cross-sectional shape data cut from a three-dimensional computer-aided design (CAD) data as an environmental map and structural shapes measured by a range sensor. As a range sensor, an ultrasonic sensor which is two-dimensional scanning-type was developed. The reflected signals of the ultrasonic sensor have some noise. Only structural shape data are extracted from the reflected signals. The image correlation is used as the matching method. Experiments to evaluate the performance of the proposed system were implemented at a mock-up environment. As a result, it was confirmed that the position was detected with an accuracy of 100 mm. The error is mainly caused by measurement error of the ultrasonic sensor that is used to calculate structural shapes. We concluded to improve the measurement accuracy of the ultrasonic sensor to reduce localization error.     

Application of nine air-dried Capsicum annum cultivars as food preservative: Micronutrient content,antioxidant activity,and foodborne pathogens inhibitory effects

Capsicum annum cultivars Yellow cayenne, Portafortuna, Idealino, Sole, Duemila, Pellegrino, Fantasia, Loco, and Effix were investigated for their antioxidant properties and foodborne pathogens inhibitory activity. The total phenols, flavonoids, anthocyanins, capsaicinoids, carotenoids, ascorbic acid, and vitamin E content were also determined. Duemila and Portafortuna cultivars showed the highest total phenol content with values of 924.3 and 935.0 mg of chlorogenic acid equivalents/100 g dried weight, respectively. Idealino pepper presented the highest capsaicin content (2932.1 μg/g dried weight). The antioxidant capacity was evaluated by using 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid test, 2,2-diphenyl-1-picrylhydrazyl test, and ferric reducing ability power assay. Both Pellegrino and Idealino samples exhibited a promising radical scavenging ability against 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid radical with IC₅₀ values of 45.2 and 45.7 μg/mL, respectively. All the extracts were able to inhibit the growth of Staphylococcus aureus and Listeria monocytogenes investigated strains. The most active are Effix and Fantasia peppers with minimal inhibitory concentration between 12.5 and 25.0 mg/mL, respectively. Overall, these results support the use of these pepper species as dried extract in food preservation.     

The utility of multi-sensor data for mapping eroded lands

The availability of remote sensing data with improved spatial, spectral and radiometric resolution is now available to fully exploit their potential for a specific application subject to the relative merits and the limitations of each sensor's data. Presented here is a case study where Landsat MSS and TM; and SPOT MLA data for part of the Bijapur district, southern India, which were acquired on the same day, have been evaluated for mapping eroded lands. The approach involves the geometric registration of all three data to a common map grid using tie points and third order polynomial transform; and resampling the MSS and TM data to a 20m by 20 m pixel dimension and radiometric normalization. Thematic maps showing eroded lands were generated on a micro-VAXbased DIPIX system using a maximum likelihood classifier. Accuracy estimates were made for the thematic maps following stratified unaligned random sampling technique, and subsequently, computing overall accuracy and Kappa coefficient. Spectral separability and classification accuracy was maximum from SPOT-MLA data followed by a combination of Landsat MSS band 1, SPOT-MLA band 2 and Landsat TM band 4; Landsat TM, a combination of Landsat MSS, TM and SPOT MLA; and Landsat MSS data.     

基于故障统一模型的故障检测策略

随着集成电路制造工艺持续向纳米尺度的推进,数字电路受老化、工艺误差、软错误等故障所造成的时序偏差越发突出,严重威胁了电路的“时序安全”。文中通过分析故障影响信号稳定性侵犯模型,提出了一种新的故障检测模型。该模型扩展了现有的故障检测能力,通过使用C单元作为稳定性检测器输出单元,提高了其对高速的适应性。仿真结果显示,与已有结果相比其具有明显的速度优势和较小的硬件开销。     

基于C8051F410单片机的光纤传输组件设计

光纤通信带宽大、信噪比低、抗干扰能力强,在现代通信领域发挥着重要作用。文中选用C8051F410单片机作为微处理器,结合其他外围电路设计出一款光纤传输组件,并介绍了包括模块的整体架构、硬件电路搭建、软件开发设计和实验数据记录等内容。该组件具有体积小、精度高、操作简单的特点,实用价值明显。     

基于MC2833和MC3362的RFID系统设计

RFID系统主要由阅读器和应答器组成。阅读器包含高频接收模块、控制单元及与应答器连接的耦合元件。高频接收模块以单片集成接收芯片MC3362为核心,结合MC145151构成锁相回路,接收应答器发送的信息。应答器由耦合元件以及高频发射模块组成,其工作所需能量全部由耦合线圈提供,采用自动开关控制应答器与电源的通断以降低功耗。     

Kurt Tucholsky,John Heartfield and Deutschland,Deutschland über Alles

This essay analyses Kurt Tucholsky and John Heartfield's 1929 Deutschland, Deutschland über Alles. In this ‘picture‐book’ right‐wing nationalism, the military, the democratic system, and capitalism were trenchantly criticized. This essay argues, however, that Deutschland, Deutschland über Alles is as much about the role of photography in society as it is about Weimar's political situation. The late 1920s are generally seen as a period of medium optimism in which the new photography was in the forefront. Yet a close analysis of the use of photography in Deutschland, Deutschland über Alles nuances the so‐called optimism of Weimar visual culture and its sudden disruption by the advent of fascism in the 1930s. While from the early 1910s onwards, Tucholsky had promoted the polemical power of photography, his position shifted by the end of the 1920s. An ambivalence marked Deutschland, Deutschland über Alles: on the one hand the photographic medium was used as a critical tool; on the other, the book reflects an underlying critique of and frustration with photojournalism and its association with urban modernity.