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Two new modified carbon paste electrodes (CPEs) based on two different X type zeolites, a natural zeolitic volcanic tuff (NZ) and a NaX type synthetic zeolite (SZ), modified with methylene green (MG) were developed. Cyclic voltammetry measurements revealed a reasonably fast electron transfer rate and a good stability for both investigated electrodes. The observed differences between the electrochemical behavior of MG-NZ-CPEs and MG-SZ-CPEs (the effect of pH on the formal standard potential, the magnitude of the rate constants for heterogeneous electron transfer and electrode response decay) were explained in terms of zeolites structure. The modified electrodes showed moderate electrocatalytic effect towards H2O2 reduction and a relatively low limit of detection (0.5 mM for MG-NZ-CPEs).  相似文献   
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Wireless Personal Communications - The Internet of Things (IoT) technologies interconnect a broad range of network devices, differing in terms of size, weight, functionality, and resource...  相似文献   
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During the last years, many change projects in organizations did not have the planned success. Therefore at first, the causes for these failures and the success factors contributing to organizational change have to be discussed. To get better results, a comprehensive change management concept has been developed and tested in an ongoing research project. By using concepts for an integrated assessment and design of organizations, an approach for analyzing the current situation has been elaborated to identify “lack of integration” in the change initiatives of a company. To realize an integrated overall approach of modernization by harmonizing different methods and concepts, first, one has to prove their relationship to policy and strategy (vertical harmonization). The second step is to take into account the fact that there has to be a logical fit between the single concepts (horizontal harmonization). But even if all elements are logically coherent, that does not mean that the people working in the company also see this coherence. Therefore, in addition to the “logical fit”, one has to examine the “psychological fit”. In the end, a concept for analyzing the status quo in an organization as a result of “objective data” and “subjective data” originated.

Subsequently, instruments for harmonizing different modernizing concepts have been applied. As part of the comprehensive change management concept participatory ergonomic approaches have been used during the project. The present study shows this approach in the case of one company.  相似文献   

105.
Electrochromic properties can be enhanced by constructing photonic architectures, in which the reflectance contributes to optical modulation along with the intrinsic dynamic absorptivity of the material. However, optimization of reflectance is challenging without a rational design approach. Here, electrochemically tunable Bragg reflectors are demonstrated that are tuned to be highly transparent in the “off” state, achieving synergistic dynamic optical modulation of absorption and reflection in the visible and near‐infrared range. These Bragg stacks are composed of alternating doped semiconductor nanocrystal (NC) layers of 5 nm sized oxygen vacancy‐doped WO3?x and 15 nm sized 0.4 at% Sn:In2O3 NCs. Combining judicious NC selection and processing optimization with guidance from optical simulations, optimized Bragg stacks are implemented for electrochromic window applications. NCs with high absorption coefficients are essential for strong transmission modulation, though this characteristic limits the dynamic range of the Bragg reflectance. Optimal reflectance modulation including a highly transparent “off” state is confirmed with in situ reflectance and transmittance measurement. More broadly, ligand‐stripped NCs can enable fabrication of complex device architectures on low‐cost flexible substrates. These results guide the design rules for accessing different types of doped semiconductor NC‐based tunable Bragg stacks, an exemplary photonic structure, over a broad wavelength range.  相似文献   
106.
The agro‐industrial wastes, sugarcane bagasse (SB) and asparagus peel (AP), were used to enhance the properties of biodegradable foam trays based on sweet potato starch‐based foam trays (starch/SB and starch/AP trays, respectively). Starch/SB and starch/AP trays containing different concentrations of SB and AP (0%‐40%, w/w) were prepared, and their microstructure and physical, thermal, and mechanical properties were characterized. The addition of fibers wastes allowed obtaining a yellowish foam tray with lower luminosity and higher porosity, mechanical resistance, deformability, and better ability to absorb water as compared with the sweet potato starch foam trays without fibers. The addition of SB yielded foam trays less porous, with lower water absorption capacity and greater tensile strength than the addition of AP. Higher concentrations of AP fibers (greater than 30%) generate more extendible foam trays. The addition of fibrous wastes improved the thermal stability of the sweet potato starch foam trays. The composite foam trays produced in this work could be used as substitutes for expanded polystyrene in dry food packaging.  相似文献   
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This paper describes how a group of practitioners and researchers are working across disciplines at Nottingham Trent University in the area of Technical Textiles. It introduces strands of ongoing enquiry centred around the development and application of stretch sensors on the body, focusing on how textile and fashion knowledge are being reflexively revealed in the collaborative development of seamful wearable concepts, and on the tensions between design philosophies as revealed by definitions of purpose. We discuss the current research direction of the Aeolia project, which seeks to exploit the literal gaps found in pattern cutting for fitted stretch garments towards experiential forms and potential interactions. Normative goals of fitness for purpose and seamlessness are interrogated and the potential for more integrated design processes, which may at first appear ‘upside down’, is discussed.  相似文献   
110.
Early automatic detection of fungal infections in post-harvest citrus fruits is especially important for the citrus industry because only a few infected fruits can spread the infection to a whole batch during operations such as storage or exportation, thus causing great economic losses. Nowadays, this detection is carried out manually by trained workers illuminating the fruit with dangerous ultraviolet lighting. The use of hyperspectral imaging systems makes it possible to advance in the development of systems capable of carrying out this detection process automatically. However, these systems present the disadvantage of generating a huge amount of data, which must be selected in order to achieve a result that is useful to the sector. This work proposes a methodology to select features in multi-class classification problems using the receiver operating characteristic curve, in order to detect rottenness in citrus fruits by means of hyperspectral images. The classifier used is a multilayer perceptron, trained with a new learning algorithm called extreme learning machine. The results are obtained using images of mandarins with the pixels labelled in five different classes: two kinds of sound skin, two kinds of decay and scars. This method yields a reduced set of features and a classification success rate of around 89%.  相似文献   
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