Pre-Stressed Piezoelectric Bimorph Micro-Actuators Based on Machined 40-Micron PZT Ceramic Thick Films—Batch Scale Fabrication and Integration With MEMS

Author(s):  
Stephen Wilson ◽  
Renaud Jourdain ◽  
Sam Owens

The projected force-displacement capability of piezoelectric ceramic films in the 20–50μm thickness range suggests that they are well suited to many micro-fluidic and micro-pneumatic applications. Furthermore when they are configured as bending actuators and operated at ∼1V/μm they do not necessarily conform to the high-voltage, very low-displacement piezoelectric stereotype. Even so they are rarely found today in commercial micro-electromechanical devices, such as micro-pumps and micro-valves, and the main barriers to making them much more widely availability would appear to be processing incompatibilities rather than commercial desirability. In particular, the issues associated with integration of these devices into MEMS at the production level are highly significant and they have perhaps received less attention in the mainstream than they deserve. This paper describes a fabrication route based on ultra-precision ceramic machining and full-wafer bonding for cost-effective batch-scale production of thick film PZT bimorph micro-actuators and their integration with MEMS. The resulting actuators are pre-stressed (ceramic in compression) which gives them added performance, they are true bimorphs with bi-directional capability and they exhibit full bulk piezoelectric ceramic properties. The devices are designed to integrate with ancillary systems components using transfer bonding techniques. The work forms part of the European Framework 6 Project ‘Q2M - Quality to Micro’.

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 290
Author(s):  
Chih-Yu Cheng ◽  
Chia-Huang Tsai ◽  
Pei-Jyun Liou ◽  
Chi-Hang Wang

For pilot-scale production of chito-oligosaccharides, it must be cost-effective to prepare designable recombinant chitosanase. Herein, an efficient method for preparing recombinant Bacillus chitosanase from Escherichia coli by elimination of undesirable substances as a precipitate is proposed. After an optimized culture with IPTG (Isopropyl β-d-1-thiogalactopyranoside) induction, the harvested cells were resuspended, disrupted by sonication, divided by selective precipitation, and stored using the same solution conditions. Several factors involved in these procedures, including ion types, ionic concentration, pH, and bacterial cell density, were examined. The optimal conditions were inferred to be pH = 4.5, 300 mM sodium dihydrogen phosphate, and cell density below 1011 cells/mL. Finally, recombinant chitosanase was purified to >70% homogeneity with an activity recovery and enzyme yield of 90% and 106 mg/L, respectively. When 10 L of 5% chitosan was hydrolyzed with 2500 units of chitosanase at ambient temperature for 72 h, hydrolyzed products having molar masses of 833 ± 222 g/mol with multiple degrees of polymerization (chito-dimer to tetramer) were obtained. This work provided an economical and eco-friendly preparation of recombinant chitosanase to scale up the hydrolysis of chitosan towards tailored oligosaccharides in the near future.


Actuators ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 59
Author(s):  
Deepak Rajaram Patil ◽  
Venkateswarlu Annapureddy ◽  
J. Kaarthik ◽  
Atul Thakre ◽  
Jun Akedo ◽  
...  

Conventional thin-film processing techniques remain inadequate for obtaining superior dense ceramic thick films. The incompatibility of ceramic films prepared via other methods, such as screen printing, spin coating, and sputtering, is a major obstacle in the fabrication of thick film-based ceramic electronic components. The granule spray in vacuum (GSV) processes and aerosol deposition (AD) are important coating approaches for forming dense ceramic thick films featuring nanoscale crystallite structures at room temperature, which offer excellent material properties and facilitate cost-effective production. AD ceramic coatings require the acceleration of solid-state submicron ceramic particles via gas streams with a velocity of a few hundred meters per second, which are then wedged onto a substrate. This process is economical and particularly useful for the fabrication of piezoelectric thick film-based microactuators, energy harvesters, sensors, and optoelectronic devices. More recently, the GSV technique was improved to achieve more uniform and homogeneous film deposition after AD. This review article presents a detailed overview of the AD and GSV processes for piezoelectric thick films in terms of recent scientific and technological applications.


2020 ◽  
Author(s):  
Götz Laible ◽  
Sally Cole ◽  
Brigid Brophy ◽  
Paul Maclean ◽  
Li How Chen ◽  
...  

ABSTRACTTherapeutic monoclonal antibodies (mAbs) represent one of the most important classes of pharmaceutical proteins to treat human diseases. Most are produced in cultured mammalian cells which is expensive, limiting their availability. Goats, striking a good balance between a relatively short generation time and copious milk yield, present an alternative platform for the cost-effective, flexible, large-scale production of therapeutic mAbs. Here, we focused on cetuximab, a mAb against epidermal growth factor receptor, that is commercially produced under the brand name Erbitux and approved for anti-cancer treatments. We generated several transgenic goat lines that produce cetuximab in their milk. Two lines were selected for detailed characterization. Both showed stable genotypes and cetuximab production levels of up to 10g/L. The mAb could be readily purified and showed improved characteristics compared to Erbitux. The goat-produced cetuximab (gCetuximab) lacked a highly immunogenic epitope that is part of Erbitux. Moreover, it showed enhanced binding to CD16 and increased antibody-dependent cell-dependent cytotoxicity compared to Erbitux. This indicates that these goats produce an improved cetuximab version with the potential for enhanced effectiveness and better safety profile compared to treatments with Erbitux. In addition, our study validates transgenic goats as an excellent platform for large-scale production of therapeutic mAbs.


2021 ◽  
Author(s):  
Sunil T. Galatage ◽  
Aditya S. Hebalkar ◽  
Shradhey V. Dhobale ◽  
Omkar R. Mali ◽  
Pranav S. Kumbhar ◽  
...  

Nanotechnology is an expanding area of research where we use to deal with the materials in Nano-dimension. The conventional procedures for synthesizing metal nanoparticles need to sophisticated and costly instruments or high-priced chemicals. Moreover, the techniques may not be environmentally safe. Therefore “green” technologies for synthesis of nanoparticles are always preferred which is simple, convenient, eco-friendly and cost effective. Green synthesis of nanoparticle is a novel way to synthesis nanoparticles by using biological sources. It is gaining attention due to its cost effective, ecofriendly and large scale production possibilities. Silver nanoparticles (AgNPs) are one of the most vital and fascinating nanomaterials among several metallic nanoparticles that are involved in biomedical applications. It has vital importance in nanoscience and naomedicines to treat and prevent vital disease in human beings especially in cancer treatment. In current work we discussed different methods for synthesis of AgNPs like biological, chemical and physical along with its characterization. We have also discussed vital importance of AgNPs to cure life threatnign diseases like cancer along with antidiabetic, antifungal, antiviral and antimicrobial alog with its molecular mode of action etc. Finally we conclude by discussing future prospects and possible applications of silver nano particles.


2013 ◽  
Vol 2013 (DPC) ◽  
pp. 000377-000397
Author(s):  
Jon G. Aday ◽  
Ted Tessier ◽  
Kazuhisa Itoi ◽  
Satoshi Okude

Embedded die substrate technologies are being developed in an assortment of configurations and for different market segments. The technology being discussed in this paper will be focused on both a fan out technology – ChipsetT Fan-Out and a system in package approach (ChipsetT SiP) in which a multiple component bill of materials (BOM) is used. The Chipset process is based on the WABE (Wafer and Board Level Embedding) technology. WABE technology is based on co-lamination of multilayer polyimide flex wiring and conductive z-axis sintered metal interconnections. This ChipsetT Fan Out technology allows for large scale production of fan out type solutions which can allow for very thin packages in addition to unique pin out solutions such as pin compatibility for a competitor part. The ChipsetT SiP also allows embedding of single or multiple silicon die and/or components. Additional components can also be placed using conventional SMT on the top or bottom side of the package. There is a great deal of design flexibility with this technology which makes it a great solution for applications trying to reduce their x-y size or z-height. When utilizing RDL technology on the embedded die we are able to do the fine pitch routing in order to allow the substrate to route at larger pitches ensuring an overall cost effective solution. This paper will focus on the different classes of applications that have benefited from this technology and will discuss the benefits and tradeoffs of the different solutions that have been engineered. Assembly and reliability data will be presented on several of the applications showing a robust solution set.


Author(s):  
Agnes Marie Horn ◽  
Mons Hauge ◽  
Per-Arne Ro̸stadsand ◽  
Bjarne Bjo̸rnbakk ◽  
Peer Dahlberg ◽  
...  

A large diameter high strength titanium free-hanging catenary riser was evaluated by the Demo 2000 Ti-Rise project, from initiative of the Kristin Field development license. In order to reduce the uncertainties related to the schedule, cost, and special technical issues identified in the work related to a similar riser for future installation on the A˚sgard B semi-submersible platform, a fabrication qualification of a full scale riser in titanium was run. Several full-scale production girth welds were made in an in-situ fabrication environment. The welding was performed on extruded titanium grade 23 (ASTM) pipes with an ID of 25.5″) and wall thickness of 30 mm. The main challenge was to develop a highly productive TIG orbital welding procedure, which produced welds with as low pore content as possible. It is well known that sub-surface pores often are initiation sits for fatigue cracks in high strength titanium welds. This paper describes how a greatly improved productivity was obtained in combination with a high weld quality. NDT procedures were developed whit the main on the reliability to detect and locate possible sub-surface weld defects, volumetric defects such as pores and tungsten particles and planar defects such as lack of fusion. The results from the actual Non Destructive Testing (NDT), the mechanical testing, and the fatigue testing of the subjected welds are presented. The response of the catenary is optimised by varied distribution of weight coating along the riser’s length. A satisfactory weight coating with sufficient strength, bond strength, and wear properties was developed and qualified. The riser is planned to be fabricated from extruded titanium pipes, welded together onshore to one continuous piece. The field coating is added and the riser is loaded into the sea and towed offshore and installed.


2016 ◽  
Vol 30 (2) ◽  
pp. 35-42
Author(s):  
Durga Prasad Pandey ◽  
Hari Datta Bhattarai

Ramalin, a new L-glutamic acid derivative of phenylhydrazide (Y-glutamyl-N'-(2-hydroxyphenyl) hydrazide, 1) was isolated from the Antarctic lichen, Ramalina terebrata after a series of bioactivity guided fractionation of crude aqueous methanolic extract. Ramalin showed stronger antioxidant activities than commercially available standards, ascorbic acid, trolox, BHA, kojic acid in both, in vitro and in vivo test systems. In addition, ramalin showed no/less toxicity effects against two human cell lines; fibroblast (CCD-986SK) cells and keratinocyte (HaCaT). Thus, realign merits for cosmetic application and industrial scale production were needed. We developed a cost effective total synthesis of ramalin with 71.5% yield and described here.


2019 ◽  
Vol 21 (2) ◽  
pp. 198-204 ◽  
Author(s):  
Kaiyu Xie ◽  
Ali Reza Kamali

Molten salt electrolytic reduction of Fe2O3 in the presence of water is proposed as a sustainable and cost-effective approach for large-scale production of iron.


Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5558
Author(s):  
Dimitra Vernardou ◽  
Charalampos Drosos ◽  
Andreas Kafizas ◽  
Martyn E. Pemble ◽  
Emmanouel Koudoumas

The need for clean and efficient energy storage has become the center of attention due to the eminent global energy crisis and growing ecological concerns. A key component in this effort is the ultra-high performance battery, which will play a major role in the energy industry. To meet the demands in portable electronic devices, electric vehicles, and large-scale energy storage systems, it is necessary to prepare advanced batteries with high safety, fast charge ratios, and discharge capabilities at a low cost. Cathode materials play a significant role in determining the performance of batteries. Among the possible electrode materials is vanadium pentoxide, which will be discussed in this review, due to its low cost and high theoretical capacity. Additionally, aqueous electrolytes, which are environmentally safe, provide an alternative approach compared to organic media for safe, cost-effective, and scalable energy storage. In this review, we will reveal the industrial potential of competitive methods to grow cathodes with excellent stability and enhanced electrochemical performance in aqueous media and lay the foundation for the large-scale production of electrode materials.


Insects ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 179 ◽  
Author(s):  
Tessa R. Grasswitz

Small-scale farms are an important component of agricultural production even in developed economies, and have an acknowledged role in providing other biological and societal benefits, including the conservation of agricultural biodiversity and enhancement of local food security. Despite this, the small-farm sector is currently underserved in relation to the development and implementation of scale-appropriate Integrated Pest Management (IPM) practices that could help increase such benefits. This review details some of the characteristics of the small farm sectors in developed economies (with an emphasis on the USA and Europe), and identifies some of the characteristics of small farms and their operators that may favor the implementation of IPM. Some of the challenges and opportunities associated with increasing the uptake of IPM in the small-farm sector are discussed. For example, while some IPM tactics are equally applicable to virtually any scale of production, there are others that may be easier (or more cost-effective) to implement on a smaller scale. Conversely, there are approaches that have not been widely applied in small-scale production, but which nevertheless have potential for use in this sector. Examples of such tactics are discussed. Knowledge gaps and opportunities for increasing IPM outreach to small-scale producers are also identified.


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