Synthesis and comparative solvatochromic studies of novel Mono azo ureido/thioureido benzimidazole dyes

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mohamed Ezzat Khalifa ◽  
Adil Abdullah Gobouri ◽  
Mohamed Hesham Hesham Mahmoud ◽  
Abdulraheem Safar Almalki ◽  
Fahad Mustafa Kabli

Purpose This paper aims to synthesize new benzimidazole dyes aiming to study the solvent effects on their absorption in Ultraviolet-visible spectra. Design/methodology/approach Ureido/thioureido hydrazonamide benzimidazoles (U/THB) are prepared by condensation of N-aryl-1H-benzo[d]imidazole-2-carbohydrazonoyl bromides with ureido and/ or thioureido reagents. The target products are fully characterized for structural elucidation by means of their spectral and elemental methods. Solvatochromic behavior of U/THB dyes has been studied in different polar protic solvents at room temperature. Findings The absorption spectra distinguish two main bands at (350 nm–442 nm) and (308 nm–382 nm) referring to n-π* and π- π* transitions of the azo groups. Dimethyl formamide induces an extremely bathochromic transition comparing to the other protic solvents. The observed bathochromic shifts indicate strong interaction with solvents in the excited state. Most dyes show one absorbance in all solvents used, so they may exist in a single tautomeric form (hydrazo form). Research limitations/implications In the present paper, the synthesis of U/THB dyes was achieved by a simple and convenient pathway. In addition, the variations in substituents attached to the chromophoric moiety could also be studied. Practical implications The new U/THB dyes are accountable for providing good knowledge about their solvation and spectral properties of an order acceptable for industrial utilization. Social implications Synthesis of these new benzimidazole derivatives and study of their solvation and spectral properties provides good knowledge, which is very useful in many industrial applications (e.g. dye-sensitized solar cell, etc.). Originality/value The synthesized mono azo U/THB dyes are novel members in the benzimidazole family, where no details regarding the synthesis of such dyes are reported before in the literature. They are superior in terms of preparation, multiple applications and spectral properties.

Sensor Review ◽  
2015 ◽  
Vol 35 (2) ◽  
pp. 141-145 ◽  
Author(s):  
Richard Bloss

Purpose – The purpose of this paper is to review the recent advancements in the development of wearable sensors which can continuously monitor critical medical, assess athletic activity, watch babies and serve industrial applications. Design/methodology/approach – The paper presents an in-depth review of a number of developments in wearable sensing and monitoring technologies for medical, athletic and industrial applications. Researchers and companies around the world were contacted to discuss their direction and progress in this field of medical condition and industrial monitoring, as well as discussions with medical personnel on the perceived benefits of such technology. Findings – Dramatic progress is being made in continuous monitoring of many important body functions that indicate critical medical conditions that can be life-threatening, contribute to blindness or access activity. In the industrial arena, wearable devices bring remote monitoring to a new level. Practical implications – Doctors will be able to replace one-off tests with continuous monitoring that provides a much better continuous real-time “view” into the patient’s conditions. Wearable monitors will help provide much better medical care in the future. Industrial managers and others will be able to monitor and supervise remotely. Originality/value – An expert insight into advancements in medical condition monitoring that replaces the one-time “finger prick” type testing only performed in the doctor’s office. It is also a look at how wearable monitoring is greatly improved and serving athletics, the industry and parents.


2014 ◽  
Vol 25 (4) ◽  
pp. 568-598 ◽  
Author(s):  
Marco Macchi ◽  
Adolfo Crespo Márquez ◽  
Maria Holgado ◽  
Luca Fumagalli ◽  
Luis Barberá Martínez

Purpose – The purpose of this paper is to propose a methodology for the engineering of E-maintenance platforms that is based on a value-driven approach. Design/methodology/approach – The methodology assumes that a value-driven engineering approach would help foster technological innovation for maintenance management. Indeed, value-driven engineering could be easily adopted at the business level, with subsequent positive effects on the industrial applications of new information and communication technologies solutions. Findings – The methodology combines a value-driven approach with the engineering in the maintenance scope. The methodology is tested in a manufacturing case to prove its potential to support the engineering of E-maintenance solutions. In particular, the case study concerns the investment in E-maintenance solutions developed in the framework of a Supervisory Control and Data Acquisition system originally implemented for production purposes. Originality/value – Based on literature research, the paper presents a methodology that is implemented considering three different approaches (business theories, value-driven engineering and maintenance management). The combination of these approaches is novel and overcomes the traditional view of maintenance as an issue evaluated from a cost-benefit perspective.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
J. Norberto Pires ◽  
Amin S. Azar ◽  
Filipe Nogueira ◽  
Carlos Ye Zhu ◽  
Ricardo Branco ◽  
...  

Purpose Additive manufacturing (AM) is a rapidly evolving manufacturing process, which refers to a set of technologies that add materials layer-by-layer to create functional components. AM technologies have received an enormous attention from both academia and industry, and they are being successfully used in various applications, such as rapid prototyping, tooling, direct manufacturing and repair, among others. AM does not necessarily imply building parts, as it also refers to innovation in materials, system and part designs, novel combination of properties and interplay between systems and materials. The most exciting features of AM are related to the development of radically new systems and materials that can be used in advanced products with the aim of reducing costs, manufacturing difficulties, weight, waste and energy consumption. It is essential to develop an advanced production system that assists the user through the process, from the computer-aided design model to functional components. The challenges faced in the research and development and operational phase of producing those parts include requiring the capacity to simulate and observe the building process and, more importantly, being able to introduce the production changes in a real-time fashion. This paper aims to review the role of robotics in various AM technologies to underline its importance, followed by an introduction of a novel and intelligent system for directed energy deposition (DED) technology. Design/methodology/approach AM presents intrinsic advantages when compared to the conventional processes. Nevertheless, its industrial integration remains as a challenge due to equipment and process complexities. DED technologies are among the most sophisticated concepts that have the potential of transforming the current material processing practices. Findings The objective of this paper is identifying the fundamental features of an intelligent DED platform, capable of handling the science and operational aspects of the advanced AM applications. Consequently, we introduce and discuss a novel robotic AM system, designed for processing metals and alloys such as aluminium alloys, high-strength steels, stainless steels, titanium alloys, magnesium alloys, nickel-based superalloys and other metallic alloys for various applications. A few demonstrators are presented and briefly discussed, to present the usefulness of the introduced system and underlying concept. The main design objective of the presented intelligent robotic AM system is to implement a design-and-produce strategy. This means that the system should allow the user to focus on the knowledge-based tasks, e.g. the tasks of designing the part, material selection, simulating the deposition process and anticipating the metallurgical properties of the final part, as the rest would be handled automatically. Research limitations/implications This paper reviews a few AM technologies, where robotics is a central part of the process, such as vat photopolymerization, material jetting, binder jetting, material extrusion, powder bed fusion, DED and sheet lamination. This paper aims to influence the development of robot-based AM systems for industrial applications such as part production, automotive, medical, aerospace and defence sectors. Originality/value The presented intelligent system is an original development that is designed and built by the co-authors J. Norberto Pires, Amin S. Azar and Trayana Tankova.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jiawei Lian ◽  
Junhong He ◽  
Yun Niu ◽  
Tianze Wang

Purpose The current popular image processing technologies based on convolutional neural network have the characteristics of large computation, high storage cost and low accuracy for tiny defect detection, which is contrary to the high real-time and accuracy, limited computing resources and storage required by industrial applications. Therefore, an improved YOLOv4 named as YOLOv4-Defect is proposed aim to solve the above problems. Design/methodology/approach On the one hand, this study performs multi-dimensional compression processing on the feature extraction network of YOLOv4 to simplify the model and improve the feature extraction ability of the model through knowledge distillation. On the other hand, a prediction scale with more detailed receptive field is added to optimize the model structure, which can improve the detection performance for tiny defects. Findings The effectiveness of the method is verified by public data sets NEU-CLS and DAGM 2007, and the steel ingot data set collected in the actual industrial field. The experimental results demonstrated that the proposed YOLOv4-Defect method can greatly improve the recognition efficiency and accuracy and reduce the size and computation consumption of the model. Originality/value This paper proposed an improved YOLOv4 named as YOLOv4-Defect for the detection of surface defect, which is conducive to application in various industrial scenarios with limited storage and computing resources, and meets the requirements of high real-time and precision.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sakthi Sadhasivam RM ◽  
Ramanathan K. ◽  
Bhuvaneswari B.V. ◽  
Raja R.

Purpose The most promising replacements for the industrial applications are particle reinforced metal matrix composites because of their good and combined mechanical properties. Currently, the need of matrix materials for industrial applications is widely satisfied by aluminium alloys. The purpose of this paper is to evaluate the tribological behaviour of the zinc oxide (ZnO) particles reinforced AA6061 composites prepared by stir casting route. Design/methodology/approach In this study, AA6061 aluminium alloy matrix reinforced with varying weight percentages (3%, 4.5% and 6%) of ZnO particles, including monolithic AA6061 alloy samples, is cast by the most economical fabrication method, called stir casting. The prepared sample was subjected to X-ray photoelectron spectroscopy (XPS) analysis, experimental density measurement by Archimedian principle and theoretical density by rule of mixture and hardness test to investigate mechanical property. The dry sliding wear behaviour of the composites was investigated using pin-on-disc tribometer with various applied loads of 15 and 20 N, with constant sliding velocity and distance. The wear rate, coefficient of friction (COF) and worn surfaces of the composite specimens and their effects were also investigated in this work. Findings XPS results confirm the homogeneous distribution of ZnO microparticles in the Al matrix. The Vickers hardness result reveals that higher ZnO reinforced (6%) sample have 34.4% higher values of HV than the monolithic aluminium sample. The sliding wear tests similarly show that increasing the weight percentage of ZnO particles leads to a reduced wear rate and COF of 30.01% and 26.32% lower than unreinforced alloy for 15 N and 36.35% and 25% for 20 N applied load. From the worn surface morphological studies, it was evidently noticed that ZnO particles dispersed throughout the matrix and it had strong bonding between the reinforcement and the matrix, which significantly reduced the plastic deformation of the surfaces. Originality/value The uniqueness of this work is to use the reinforcement of ZnO particles with AA6061 matrix and preparing by stir casting route and to study and analyse the physical, hardness and tribological behaviour of the composite materials.


Circuit World ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Rohollah Abdollahi

Purpose The purpose of this paper is to provide a T autotransformer based 12-pulse rectifier with passive harmonic reduction in more electric aircraft applications. The T autotransformer uses only two main windings which result in volume, space, size, weight and cost savings. Also, the proposed unconventional inter-phase transformer (UIPT) with a lower kVA rating (about 2.6% of the load power) compared to the conventional inter-phase transformer results in a more harmonic reduction. Design/methodology/approach To increase rating and reduce the cost and complexity of a multi-pulse rectifier, it is well known that the pulse number must be increased. In some practical cases, a 12-pulse rectifier (12PR) is suggested as a good solution considering its simple structure and low weight. But the 12PR cannot technically meet the standards of harmonic distortion requirements for some industrial applications, and therefore, they must be used with output filters. In this paper, a 12PR is suggested, which consists of a T autotransformer 12PR and a passive harmonic reduction (PHR) based on the UIPT at direct current (DC) link. Findings To show the advantage of this new combination over other solutions, simulation results are used, and then, a prototype is implemented to evaluate and verify the simulation results. The simulation and experimental test results show that the input current total harmonic distortion (THD) of the suggested 12PR with a PHR based on UIPT is less than 5%, which meets the IEEE 519 requirements. Also, it is shown that in comparison with other solutions, it is cost effective, and at the same time, its power factor is near unity, and its rating is 29.92% of the load rating. Therefore, it is obvious that the proposed rectifier is a practical solution for more electric aircrafts. Originality/value The contributions of this paper are summarized as follows. The suggested design uses a retrofit T autotransformer, which meets all technical constraints, and in comparison, with other options, has less rating, weight, volume and cost. In the suggested rectifier, a PHR based on UIPT at its dc link of 12PR is used, which has good technical capabilities and lower ratings. In the PHR based on UIPT, an IPT is used, which has an additional secondary winding and four diodes. This solution leads to a reduction in input current THD and conduction losses of diodes. In full load conditions, the input line current THD and power factor are 4% and 0.99, respectively. The THD is less than 5%, which satisfies IEEE-519 and DO-160G requirements.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ansheng Zhang ◽  
Mingyu Zhang ◽  
Jing Wang ◽  
Jianjun Zhang ◽  
Zhaohua Shang ◽  
...  

Purpose The purpose of this paper is to study the influence of surface precision on the lubrication state of the roller chain under adequate and rare oil supply conditions, respectively. Design/methodology/approach The straightness error and roughness error of the pin generatrices were measured and the influence of surface precision on the lubrication behavior under steady state and reciprocating motion was studied through optical interference experiments. Findings The lubrication state is strongly influenced by the surface precision of the roller surface both under adequate oil supply and rare oil supply conditions. Originality/value In industrial applications, the machining errors of parts cannot be completely eliminated. Studying the influence of the surface precision on the lubrication behavior of pin–bush pairs can provide the experimental basis for the optimal design of the bush roller chains.


2020 ◽  
Vol 86 (17) ◽  
Author(s):  
Miha Bahun ◽  
Marko Šnajder ◽  
Dušan Turk ◽  
Nataša Poklar Ulrih

ABSTRACT Pernisine is a subtilisin-like protease that was originally identified in the hyperthermophilic archaeon Aeropyrum pernix, which lives in extreme marine environments. Pernisine shows exceptional stability and activity due to the high-temperature conditions experienced by A. pernix. Pernisine is of interest for industrial purposes, as it is one of the few proteases that has demonstrated prion-degrading activity. Like other extracellular subtilisins, pernisine is synthesized in its inactive pro-form (pro-pernisine), which needs to undergo maturation to become proteolytically active. The maturation processes of mesophilic subtilisins have been investigated in detail; however, less is known about the maturation of their thermophilic homologs, such as pernisine. Here, we show that the structure of pro-pernisine is disordered in the absence of Ca2+ ions. In contrast to the mesophilic subtilisins, pro-pernisine requires Ca2+ ions to adopt the conformation suitable for its subsequent maturation. In addition to several Ca2+-binding sites that have been conserved from the thermostable Tk-subtilisin, pernisine has an additional insertion sequence with a Ca2+-binding motif. We demonstrate the importance of this insertion for efficient folding and stabilization of pernisine during its maturation. Moreover, analysis of the pernisine propeptide explains the high-temperature requirement for pro-pernisine maturation. Of note, the propeptide inhibits the pernisine catalytic domain more potently at high temperatures. After dissociation, the propeptide is destabilized at high temperatures only, which leads to its degradation and finally to pernisine activation. Our data provide new insights into and understanding of the thermostable subtilisin autoactivation mechanism. IMPORTANCE Enzymes from thermophilic organisms are of particular importance for use in industrial applications, due to their exceptional stability and activity. Pernisine, from the hyperthermophilic archaeon Aeropyrum pernix, is a proteolytic enzyme that can degrade infective prion proteins and thus has a potential use for disinfection of prion-contaminated surfaces. Like other subtilisin-like proteases, pernisine needs to mature through an autocatalytic process to become an active protease. In the present study, we address the maturation of pernisine and show that the process is regulated specifically at high temperatures by the propeptide. Furthermore, we demonstrate the importance of a unique Ca2+-binding insertion for stabilization of mature pernisine. Our results provide a novel understanding of thermostable subtilisin autoactivation, which might advance the development of these enzymes for commercial use.


2021 ◽  
Vol 2050 (1) ◽  
pp. 011001

Considering the current situation of COVID-19 and travel restrictions, the 3rd International Conference on Industrial Applications of Big Data and Artificial Intelligence (BDAI 2021) which was planned to be held in Wuhan. China from Sept. 23 to 25, 2021 was changed into virtual conference on Sept. 24, 2021 via Tencent Meeting (Voov) software. BDAI 2021 was organized by China University of Geosciences (Wuhan), sponsored by Hong Kong Society of Mechanical Engineers (HKSME). The Technical Program committee received a total of 38 paper submissions from all over the world, among which 20 papers were accepted, and more than 30 participants attended the conference online, they were from China, Australia, Thailand, Malaysia, India, Japan, UK and more. Four renowned speakers given speeches about their latest research and reports. They are: Prof. Dan Zhang from York University, Canada; Prof. Lefei Zhang from Wuhan University. China: Prof. Deze Zeng from China University of Geosciences (Wuhan), China and Assoc. Prof. Simon James Fong from University of Macau. Macau S.A.R., China. The conference also had 1 technical session and 1 poster sessions. This conference aims to provide a platform for researchers and engineers to share their ideas, recent developments, and successful practices in energy engineering. The participants of the conference were from almost every part of the world, with various background such as academia, industry, and well-known entrepreneurs. Each keynote speech lasted 40 minutes, and authors presentation 15 minutes. Each presentation was included with questions and answers. BDAI 2021 became an effective communication platform for all the participants over the world and unlike some that claim international reach this conference was truly international. The conference proceeding is a compilation of the accepted papers and represent an interesting outcome of the conference. This book covers 3 chapters: 1. Artificial Intelligence: 2. Big Data Technology; 3. Robot System. We would like to acknowledge all of those who supported BDAI 2021. Each individual and institutional help were very important for the success of this conference. Especially we would like to thank the committee chairs, committee members and reviewers, for their tremendous contribution in conference organization and peer review of the papers. We sincerely hope that BDAI 2021 will be a fomrn for excellent discussions that will put forward new ideas and promote collaborative research and support researchers as they take their work forward. We are sure that the proceedings will serve as an important research source of references and the knowledge, which will lead to not only scientific and engineering progress but also other new products and processes. Dan Zhang, York University, Canada


2015 ◽  
Vol 59 (10) ◽  
pp. 6296-6307 ◽  
Author(s):  
Petra Keller ◽  
Christoph Müller ◽  
Isabel Engelhardt ◽  
Ekkehard Hiller ◽  
Karin Lemuth ◽  
...  

ABSTRACTFungal infections are a leading cause of morbidity and death for hospitalized patients, mainly because they remain difficult to diagnose and to treat. Diseases range from widespread superficial infections such as vulvovaginal infections to life-threatening systemic candidiasis. For systemic mycoses, only a restricted arsenal of antifungal agents is available. Commonly used classes of antifungal compounds include azoles, polyenes, and echinocandins. Due to emerging resistance to standard therapies, significant side effects, and high costs for several antifungals, there is a need for new antifungals in the clinic. In order to expand the arsenal of compounds with antifungal activity, we previously screened a compound library using a cell-based screening assay. A set of novel benzimidazole derivatives, including (S)-2-(1-aminoisobutyl)-1-(3-chlorobenzyl)benzimidazole (EMC120B12), showed high antifungal activity against several species of pathogenic yeasts, includingCandida glabrataandCandida krusei(species that are highly resistant to antifungals). In this study, comparative analysis of EMC120B12 versus fluconazole and nocodazole, using transcriptional profiling and sterol analysis, strongly suggested that EMC120B12 targets Erg11p in the ergosterol biosynthesis pathway and not microtubules, like other benzimidazoles. In addition to the marker sterol 14-methylergosta-8,24(28)-dien-3β,6α-diol, indicating Erg11p inhibition, related sterols that were hitherto unknown accumulated in the cells during EMC120B12 treatment. The novel sterols have a 3β,6α-diol structure. In addition to the identification of novel sterols, this is the first time that a benzimidazole structure has been shown to result in a block of the ergosterol pathway.


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