NaWuReT-Workshop: Forschung in der Reaktionstechnik für und mit der Gesellschaft

In this article, the results of the NaWuReT (Early Career Reaction Engineers) workshop on the topic “Are we doing relevant science?” are presented. The topics “(In)surmountable hurdles for Citizen Scientists in reaction engineering?” and “Circular Economy in reaction engineering with/for society?” were discussed. Therefrom, a variety of ideas and suggestions were extracted.     

Design of Ti4+-doped Li3V2(PO4)3/C fibers for lithium energy storage

In this work, we propose a facile approach to fabricate Ti⁴⁺-doped Li₃V₂(PO₄)₃/C (abbreviated as C-LVTP) nanofibers using an electrospinning route followed by a high temperature treatment. In this designed nanocomposite, the ultrafine LVTP dots are homogeneously dispersed into one-dimensional carbon nanofibers and the Ti⁴⁺ doping does not destroy the crystal structure of monoclinic Li₃V₂(PO₄)₃. Compared to the undoped Li₃V₂(PO₄)₃/C (abbreviated as C-LVP), the as-fabricated C-LVTP fibers present higher reversible capacity, superior high-rate capability as well as better cyclic property. Especially, the C-LVT_7%P cathode delivers not only high capacities of 187.2 and 160.3 mAh g^?1 at 0.5 and 10 C respectively, but also stable cyclic property with the reversible capacity of 135.8 mAh g^?1 at 20 C following 500-cycle spans. The good battery characteristics of C-LVT_7%P can be mainly ascribed to Ti⁴⁺ doping, which can increase the electrical conductivity and Li⁺ diffusion coefficient.     

Unique CNTs-chained Li4Ti5O12 nanoparticles as excellent high rate anode materials for Li-ion capacitors

Composite anode materials with a unique architecture of carbon nanotubes (CNTs)-chained spinel lithium titanate (Li₄Ti₅O₁₂, LTO) nanoparticles are prepared for lithium ion capacitors (LICs). The CNTs networks derived from commercial conductive slurry not only bring out a steric hindrance effect to restrict the growth of Li₄Ti₅O₁₂ particles but greatly enhance the electronic conductivity of the CNTs/LTO composites, both have contributed to the excellent rate capability and cycle stability. The capacity retention at 30 C (1 C = 175 mA g^?1) is as high as 89.7% of that at 0.2 C with a CNTs content of 11 wt%. Meanwhile, there is not any capacity degradation after 500 cycles at 5 C. The LIC assembled with activated carbon (AC) cathode and such a CNTs/LTO composite anode displays excellent energy storage properties, including a high energy density of 35 Wh kg^?1 at 7434 W kg^?1, and a high capacity retention of 87.8% after 2200 cycles at 1 A g^?1. These electrochemical performances outperform the reported data achieved on other LTO anode-based LICs. Considering the facile and scalable preparation process proposed herein, the CNTs/LTO composites can be very potential anode materials for hybrid capacitors towards high power-energy outputs.     

Taxonomy of digital community currency platforms*

ABSTRACT

Community currencies are used to pay for products or services within specific groups defined by geographical boundaries or specific common interests. Financial crises, social emergence in developing countries, and increased access to digital devices have stimulated a growing number of communities worldwide to develop digital currency projects. These projects use technologies ranging from traditional plastic cards to mobile phones and blockchain technologies. Following the design science research approach, this paper analyzes digital community currencies (DCCs) by developing a taxonomy based on platform architecture, governance, transactionality and virtuality. By investigating 22 DCC platforms around the world, 4 groups were distinguished: local, proprietary, commons and cyber. The identification of these four different groups of digital community currencies allows us to better discuss the potentials and limitations of each one of them. The presented taxonomy can be useful to researchers and practitioners both to explain and to design DCC platforms. Discussing each of the emerging categories from the proposed taxonomy helps us to provide insights into DCCs, offering a new theoretical frame for investigating the particular case of digital payment platforms.     

Prediction methods and applications in the science of science: A survey

Science of science has become a popular topic that attracts great attentions from the research community. The development of data analytics technologies and the readily available scholarly data enable the exploration of data-driven prediction, which plays a pivotal role in finding the trend of scientific impact. In this paper, we analyse methods and applications in data-driven prediction in the science of science, and discuss their significance. First, we introduce the background and review the current state of the science of science. Second, we review data-driven prediction based on paper citation count, and investigate research issues in this area. Then, we discuss methods to predict scholar impact, and we analyse different approaches to promote the scholarly collaboration in the collaboration network. This paper also discusses open issues and existing challenges, and suggests potential research directions.     

Misconceptions of human factors concepts

Abstract

Like many scientific topics, Human Factors, and Ergonomics concepts are susceptible to being misunderstood by people unfamiliar with the subject matter. Most of the time these misunderstandings are harmless, like when a safety poster within a work setting encourages employees to 'overcome complacency'. This misunderstanding of complacency suggests it is a motivational aspect of human behaviour correctable with encouragement, whereas the human factors approach to overcoming complacency would be to evaluate how task design could diminish the destructive consequences of unexpected changes within a routine setting. No harm comes from the message within the safety poster, other than some wasted ink and paper, but misconceptions among particular audiences can eventually result in dire consequences for the human operator. This paper presents recent evidence that the concepts are being misapplied by casual consumers of human factors, particularly in the aftermath of accidents within complex systems, in ways detrimental to the core mission of improving the well-being of the human operator. Later, because this special issue presents new ways to demonstrate value via return on investment, practical efforts we can take to overcome such misconceptions are suggested.     

挤压豌豆纤维粉制备的不可溶膳食纤维油脂吸附能力研究

对不同挤压条件下不可溶膳食纤维对植物油和动物油吸附能力进行研究。以豌豆纤维粉为原料,通过改变挤压条件,改善豌豆纤维粉的物性,利用酶水解去除物料中的淀粉、蛋白质,得到不可溶膳食纤维。豌豆纤维粉挤出物和不可溶膳食纤维,随着物料水分、机筒温度、螺杆转速的升高,对于植物油和动物油的吸油量皆为先升高再降低,整体的吸油量后者高于前者。豌豆纤维粉挤出物去除淀粉和蛋白质前后吸附植物油能力由0.50 g/g提高到1.27 g/g;吸附动物油能力由0.56 g/g提高到1.75 g/g。结果表明经挤压技术改性的不可溶膳食纤维粉对油脂的吸附能力有所提高。     

Effects of risks on the performance of business process outsourcing projects: The moderating roles of knowledge management capabilities

Although business process outsourcing (BPO) can reduce cost and enhance the competitiveness of firms, the implementation of BPO projects is unsatisfactory. By integrating knowledge management capability theory and risk-based view, we develop a model of how different types of BPO risks affect project satisfaction and how knowledge management capability changes the influences of BPO risks. A survey of 121 BPO projects was conducted among BPO client department manager and project manager through a pairwise design. Empirical evidence reveals that social system, technical system, and project management risks negatively affect BPO project satisfaction. However, cultural, technological, and structural levels of knowledge management capabilities weaken the negative risk effects of social system, technical system, and project management, respectively. Different types of risks and knowledge management capabilities should be matched to achieve effective risk management.     

Processing capabilities of micro ultrasonic machining for hard and brittle materials: SPH analysis and experimental verification

Micro ultrasonic machining (micro-USM) is an unconventional micromachining technology that has capability to fabricate high aspect ratio micro-holes, intricate shapes and features on various hard and brittle materials. The material removal in USM is based on brittle fracture of work materials. The mechanical properties and fracture behaviour are different for varied hard and brittle materials, which would make a big difference in the processing capability of micro-USM. To study the processing capability of USM and exploit its potential, the material removal of work materials, wear of abrasive particles and wear of machining tools in USM of three typical hard and brittle materials including float glass, alumina, and silicon carbide were investigated in this work. Both smoothed particle hydrodynamics (SPH) simulations and verification experiments were conducted. The material removal rate is found to decrease in the order of glass, alumina, and silicon carbide, which can be well explained by the simulation results that cracking of glass is faster and larger compared to the other materials. Correspondingly, the tool wear rate also dropped significantly thanks to the faster material removal, and a formation of concavity on the tool tip center due to intensive wear was prevented. The SPH model is proved useful for studying USM of different hard and brittle materials, and capable of predicting the machining performance.