scholarly journals A Brief Review on the Recent Evolution in Piezoelectric Linear Ultrasonic Motors

Author(s):  
Shalini Mukhopadhyay ◽  
Basudeba Behera ◽  
Jayendra Kumar

Abstract This article represents the various recent advancements in the field of Piezoelectric Ultrasonic Motors especially in linear type. The construction and operation principles evolving time to time. We have accumulated and presented a brief discussion on the linear ultrasonic motor including its working principles, initial designs and recent advancements in this article. These motors have had increasing applications in recent years and have been developing rapidly due to its simplicity of construction and good performance. The potential applications are expanding lately to various areas such as medical devices, precise positioning systems, astronautical devices, tactile feedback systems, and many more. Owing to the wide range of applications, simple and compact design, rapidly increasing miniaturization, and the several advantages of the linear ultrasonic motor, it has been a vastly researched area in the last few decades. More and more effort is being put into creating smaller and efficient designs, structures and materials of the device, with stable and upgraded output performance, and acceptable range of frictional wear enabling prolonged usage.

2015 ◽  
Vol 0 (0) ◽  
Author(s):  
Wei Zheng ◽  
Jing-Liang Zhou ◽  
Yu-Zhen Ruan

AbstractAs a new type of motor, the traveling wave type rotary ultrasonic motors (TRUM) have a wide range of applications. However, the friction between stator and rotor leads to its poor start reliability, which retards the progress of application of ultrasonic motors. Sometimes TRUMs which are widely used cannot start after storage. Height of tooth of the ultrasonic motor’s stator is one of the factors affecting TRUM’s start stabilizing. In this paper, combined with the ultrasonic motor running mechanism, the factors that affect TRUM’s start reliability are studied. Model of ultrasonic motor stator tooth height is analyzed by finite element analysis (FEA). Five TRUMs with different tooth heights are fabricated and measured. A TRUM with 1.85 mm tooth height can start properly in humidity 90%, but ultrasonic motors with 1.8–1.9 mm tooth height cannot start properly under the same conditions.


2013 ◽  
Vol 385-386 ◽  
pp. 777-780 ◽  
Author(s):  
Zhao Li Xu ◽  
Zhi Yuan Yao

Linear ultrasonic motor has a wide range of applications in the aerospace field, which requires not only high accuracy of the control, but also the need for a stable running speed. For broadening its application, it is necessary to keep the linear ultrasonic motor having a stable speed. This paper first proposes AR module method for linear ultrasonic motor. The speed of the linear ultrasonic motor is measured by the driving and controlling system. By minimizing the targeted speed value and the actual speed value, we can keep the linear ultrasonic motor stable. This text also compares this method with the traditional PID method. The average deviation of AR is 24%.


2016 ◽  
Vol 10 (4) ◽  
pp. 557-563 ◽  
Author(s):  
Manabu Aoyagi ◽  
◽  
Ryuichi Nakayasu ◽  
Hidekazu Kajiwara ◽  

A linear ultrasonic motor (LUSM) with two parallel beams and two multilayer piezoelectric actuators (MPAs) has been developed. The MPAs are aligned across the beams, and the force and displacement generated by the MPAs result in the deformation of the beams in the orthogonal direction. The LUSM has two types of operation modes: dynamic and static. In dynamic operation, the MPAs are driven by alternating voltages with a phase difference, and elliptical displacement motions are generated on the surfaces of the beams. Objects touching the surfaces of the beams can be moved in the same direction by friction. In addition, micro positioning is available over a wide range by combining dynamic and static operations. The characteristics of the LUSM include a maximum speed of 41 mm/s and a maximum thrust of 3.4 N at an operating voltage of 20 Vp-p. A movement range of approximately 8 μm has been confirmed during static operation.


Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1566
Author(s):  
Oliver J. Pemble ◽  
Maria Bardosova ◽  
Ian M. Povey ◽  
Martyn E. Pemble

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy silane, also known as tetraethyl orthosilicate (TEOS) and chitosan-glutaraldehyde have been used to prepare continuous thin films using a slot-die technique which is described in detail. By way of preliminary analysis of the resulting films for comparison purposes with films made by other methods, the mechanical strength of the films produced was assessed. It was found that as expected, the hybrid films made with TEOS and glutaraldehyde both show a higher yield strength than the films made with chitosan alone. In all cases, the mechanical properties of the films were found to compare very favorably with similar measurements reported in the literature. In order to assess the possible influence of the direction in which the hydrogel passes through the slot-die on the mechanical properties of the films, testing was performed on plain chitosan samples cut in a direction parallel to the direction of travel and perpendicular to this direction. It was found that there was no evidence of any mechanical anisotropy induced by the slot die process. The examples presented here serve to illustrate how the slot-die approach may be used to create high-volume, high-area chitosan-based films cheaply and rapidly. It is suggested that an approach of the type described here may facilitate the use of chitosan-based films for a wide range of important applications.


Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 318
Author(s):  
Paula García Milla ◽  
Rocío Peñalver ◽  
Gema Nieto

Moringa oleifera belongs to the Moringaceae family and is the best known of the native Moringa oleifera genus. For centuries, it has been used as a system of Ayurvedic and Unani medicine and has a wide range of nutritional and bioactive compounds, including proteins, essential amino acids, carbohydrates, lipids, fibre, vitamins, minerals, phenolic compounds, phytosterols and others. These characteristics allow it to have pharmacological properties, including anti-diabetic, anti-inflammatory, anticarcinogenic, antioxidant, cardioprotective, antimicrobial and hepatoprotective properties. The entire Moringa oleifera plant is edible, including its flowers, however, it is not entirely safe, because of compounds that have been found mainly in the root and bark, so the leaf was identified as the safest. Moringa oleifera is recognised as an excellent source of phytochemicals, with potential applications in functional and medicinal food preparations due to its nutritional and medicinal properties; many authors have experimented with incorporating it mainly in biscuits, cakes, brownies, meats, juices and sandwiches. The results are fascinating, as the products increase their nutritional value; however, the concentrations cannot be high, as this affects the organoleptic characteristics of the supplemented products. The aim of this study is to review the application of Moringa oleifera in bakery products, which will allow the creation of new products that improve their nutritional and functional value.


AIP Advances ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 025238
Author(s):  
Danhong Lu ◽  
Qiuxiang Lin ◽  
Yanxiang Han ◽  
Bingxun Chen ◽  
Chunrong Jiang ◽  
...  

Author(s):  
Mamou Diallo ◽  
Servé W. M. Kengen ◽  
Ana M. López-Contreras

AbstractThe Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.


Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 142
Author(s):  
Hu Li ◽  
Raffaello Papadakis

Graphene is a material with outstanding properties and numerous potential applications in a wide range of research and technology areas, spanning from electronics, energy materials, sensors, and actuators to life-science and many more. However, the insolubility and poor dispersibility of graphene are two major problems hampering its use in certain applications. Tethering mono-, di-, or even poly-saccharides on graphene through click-chemistry is gaining more and more attention as a key modification approach leading to new graphene-based materials (GBM) with improved hydrophilicity and substantial dispersibility in polar solvents, e.g., water. The attachment of (poly)saccharides on graphene further renders the final GBMs biocompatible and could open new routes to novel biomedical and environmental applications. In this review, recent modifications of graphene and other carbon rich materials (CRMs) through click chemistry are reviewed.


2018 ◽  
Vol 64 (4) ◽  
pp. 656-679 ◽  
Author(s):  
Jeffrey D Freeman ◽  
Lori M Rosman ◽  
Jeremy D Ratcliff ◽  
Paul T Strickland ◽  
David R Graham ◽  
...  

Abstract BACKGROUND Advancements in the quality and availability of highly sensitive analytical instrumentation and methodologies have led to increased interest in the use of microsamples. Among microsamples, dried blood spots (DBS) are the most well-known. Although there have been a variety of review papers published on DBS, there has been no attempt at describing the full range of analytes measurable in DBS, or any systematic approach published for characterizing the strengths and weaknesses associated with adoption of DBS analyses. CONTENT A scoping review of reviews methodology was used for characterizing the state of the science in DBS. We identified 2018 analytes measured in DBS and found every common analytic method applied to traditional liquid samples had been applied to DBS samples. Analytes covered a broad range of biomarkers that included genes, transcripts, proteins, and metabolites. Strengths of DBS enable its application in most clinical and laboratory settings, and the removal of phlebotomy and the need for refrigeration have expanded biosampling to hard-to-reach and vulnerable populations. Weaknesses may limit adoption in the near term because DBS is a nontraditional sample often requiring conversion of measurements to plasma or serum values. Opportunities presented by novel methodologies may obviate many of the current limitations, but threats around the ethical use of residual samples must be considered by potential adopters. SUMMARY DBS provide a wide range of potential applications that extend beyond the reach of traditional samples. Current limitations are serious but not intractable. Technological advancements will likely continue to minimize constraints around DBS adoption.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4504
Author(s):  
Muhanna Al-shaibani ◽  
Radin Maya Saphira Radin Mohamed ◽  
Nik Sidik ◽  
Hesham Enshasy ◽  
Adel Al-Gheethi ◽  
...  

The current review aims to summarise the biodiversity and biosynthesis of novel secondary metabolites compounds, of the phylum Actinobacteria and the diverse range of secondary metabolites produced that vary depending on its ecological environments they inhabit. Actinobacteria creates a wide range of bioactive substances that can be of great value to public health and the pharmaceutical industry. The literature analysis process for this review was conducted using the VOSviewer software tool to visualise the bibliometric networks of the most relevant databases from the Scopus database in the period between 2010 and 22 March 2021. Screening and exploring the available literature relating to the extreme environments and ecosystems that Actinobacteria inhabit aims to identify new strains of this major microorganism class, producing unique novel bioactive compounds. The knowledge gained from these studies is intended to encourage scientists in the natural product discovery field to identify and characterise novel strains containing various bioactive gene clusters with potential clinical applications. It is evident that Actinobacteria adapted to survive in extreme environments represent an important source of a wide range of bioactive compounds. Actinobacteria have a large number of secondary metabolite biosynthetic gene clusters. They can synthesise thousands of subordinate metabolites with different biological actions such as anti-bacterial, anti-parasitic, anti-fungal, anti-virus, anti-cancer and growth-promoting compounds. These are highly significant economically due to their potential applications in the food, nutrition and health industries and thus support our communities’ well-being.


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