Read by QxMD icon Read


Nicholas B Waldo, Chad D Vecitis
In an effort to increase the efficiency of sonochemical reactors, this study investigates a single-source, dual-high-frequency ultrasound reactor. Experiments were conducted with a variety of piezoelectric crystals and reactor components, and for each reactor design a range of power distributions and phase shifts between the two frequencies were evaluated. Certain dual-frequency configurations produced up to a threefold increase in sonochemical efficiency, while others yeilded no improvement over a single frequency...
March 2018: Ultrasonics Sonochemistry
Shintaro Sukegawa, Takahiro Kanno, Akio Yoshimoto, Kenichi Matsumoto, Yuka Sukegawa-Takahashi, Masanori Masui, Yoshihiko Furuki
BACKGROUND: Elongated styloid process syndrome (Eagle's syndrome) is the term given to the symptomatic elongation of the styloid process or the mineralization of the stylohyoid or stylomandibular ligament. The two commonly used approaches for the surgical treatment of this syndrome are the transcervical and transoral approaches. Both have their limitations and specific intraoperative risks. Here, we report the treatment of a patient with Eagle's syndrome using the transoral approach in conjunction with piezoelectric surgery, surgical planning, and intraoperative navigation to reduce the risk of complications...
November 15, 2017: Journal of Medical Case Reports
R Sobreiro-Almeida, M N Tamaño-Machiavello, E O Carvalho, L Cordón, S Doria, L Senent, D M Correia, C Ribeiro, S Lanceros-Méndez, R Sabater I Serra, J L Gomez Ribelles, A Sempere
The aim of this work was to determine the influence of the biomaterial environment on human mesenchymal stem cell (hMSC) fate when cultured in supports with varying topography. Poly(vinylidene fluoride) (PVDF) culture supports were prepared with structures ranging between 2D and 3D, based on PVDF films on which PVDF microspheres were deposited with varying surface density. Maintenance of multipotentiality when cultured in expansion medium was studied by flow cytometry monitoring the expression of characteristic hMSCs markers, and revealed that cells were losing their characteristic surface markers on these supports...
November 11, 2017: International Journal of Molecular Sciences
Miroslav Pohanka
Tumor Necrosis Factor Alpha (TNFα) is an important marker of inflammatory processes in human body. In the current healthcare, determination of TNFα blood or plasma level is done by Enzyme Linked Immuno-Sorbent Assay (ELISA) as a primary choice method. Piezoelectric immunosensors are analytical platform recording affinity interactions on their surface. It is inferred that the immunosensors would be a functional alternative to the ELISA. In this study, antibody against TNFα was immobilized on Quartz Crystal Microbalance (QCM) sensor and the same was made on magnetic particles...
February 1, 2018: Talanta
О I Guliy, B D Zaitsev, I A Borodina, А М Shikhabudinov, S А Staroverov, L A Dykman, A S Fomin
The electro-acoustical sensor for the real-time identification of the bacteriophage FAl-SR65 is described. The polyclonal antibodies specific to the bacteriophage FAl-SR65 were for the first time obtained, and the possibility of their application to the bacteriophage detection by using the electro-acoustical method of analysis was also studied for the first time. The electro-acoustical sensor was based on the lateral electric field excited piezoelectric resonator. The frequency dependences of the real and imaginary parts of the electrical impedance of such a resonator, loaded with the virus-antibody suspension, significantly differed from those measured for the same resonator with the same virus suspension but without antibodies (control)...
February 1, 2018: Talanta
О I Guliy, B D Zaitsev, I A Borodina, А М Shikhabudinov, A A Teplykh, S A Staroverov, A S Fomin
The acoustic biological sensor for the analysis of the bacterial cells in conducting suspension was developed. The sensor represented the two channel delay line based on the piezoelectric plate of Y-X lithium niobate thick of 0.2mm. Two pairs of the interdigital transducers (IDT) for the excitation and reception of shear horizontal acoustic wave of zero order (SH0) in each channel were deposited by the method of photolithography. One channel of the delay line was electrically shorted by the deposition of thin aluminum film between IDTs...
February 1, 2018: Talanta
Yu-Hsiang Hsu, Chen-Hao Chan, William C Tang
In this paper, we report a new type of electrospinning collector that allows simultaneous collection and alignment of multiple poly(vinylidene fluoride-trifluoroethylene) piezoelectric fiber bundles with a controlled separation. The key enabling feature is the serrated teeth along the edges across an inclined gap as a part of the conductive collector. As a result, the electrical field across the gap is shaped to direct the electrospun fibers to merge into multiple bundles. The sharp points on the serrated teeth provide favorable charge dissipation points and thus fibers are preferentially formed bridging two closest sharp points across the gap...
November 13, 2017: Scientific Reports
Yan Chen, Yang Zhang, Robert Keil, Michael Zopf, Fei Ding, Oliver G Schmidt
Coercive fields of piezoelectric materials can be strongly influenced by environmental temperature. We investigate this influence using a heterostructure consisting of a single crystal piezoelectric film and a quantum dots containing membrane. Applying electric field leads to a physical deformation of the piezoelectric film, thereby inducing strain in the quantum dots and thus modifying their optical properties. The wavelength of the quantum dot emission shows butterfly-like loops, from which the coercive fields are directly derived...
November 15, 2017: Nano Letters
Bin Li, Wen-Hao Yu, Mo Chen, Jin-Long Tang, Hao Xian
In this paper, a broadband phasing algorithm is combined with a two-wavelength phasing algorithm to detect the piston error of a segmented mirror with the advantages of long range, high precision, and fast detection. Moreover, an active optics co-phasing experimental system of the segmented mirror is built to verify the algorithm's effectiveness. The segmented mirror consists of four hexagonal segments, with flat-to-flat lengths of 100 mm and radii of curvature of 2000 mm. First, a Shack-Hartmann sensor and piezoelectric actuators are used to finely co-focus the segmented mirror...
November 10, 2017: Applied Optics
Sung-Ho Shin, Seong-Young Choi, Min Hyung Lee, Junghyo Nah
We report high performance piezoelectric nanogenerators (PENGs) with nanoimprinted sol-gel BaTiO3 (BTO) nanopillar array polarized under high electric field and ultraviolet. The PENGs fabricated using this method demonstrate greatly enhanced output voltage of ~10 V and current density of ~1.2 μA cm-2, respectively, in comparison to that of flat PENG. Further, the PENG demonstrates uniform output characteristics over the entire device area thanks to uniform nanoimprint pillar array. The approach introduced here is simple, effective, reliable, and reproducible way to fabricate high performance sol-gel based PENGs and electronic devices...
November 13, 2017: ACS Applied Materials & Interfaces
Rajasekaran Ganeshkumar, Suhas Somnath, Chin Wei Cheah, Stephen Jesse, Sergei V Kalinin, Rong Zhao
Ferroelectric perovskites are an important group of materials underpinning a wide variety of devices ranging from sensors and transducers to non-volatile memories and photovoltaic cells. Despite the progress in material synthesis, ferroelectric characterization of nanoscale perovskites is still a challenge. Piezoresponse force microscopy (PFM) is one of the most popular tools for probing and manipulating nanostructures to study the ferroelectric properties. However, the interpretation of hysteresis data and alternate signal origins are critical...
November 13, 2017: ACS Applied Materials & Interfaces
Alexandre Anesi, Marzia Ferretti, Francesco Cavani, Roberta Salvatori, Michele Bianchi, Alessandro Russo, Luigi Chiarini, Carla Palumbo
Clinical advantages of piezosurgery have been already proved. However, few investigations have focused on the dynamics of bone healing. The aim of this study was to evaluate, in adult rabbits, bone regeneration after cranial linear osteotomies with two piezoelectrical devices (Piezosurgery(®) Medical - PM and Piezosurgery(®) Plus - PP), comparing them with conventional rotary osteotomes (RO). PP was characterized by an output power three times higher than PM. Fifteen days after surgery, histomorphometric analyses showed that the osteotomy gap produced with PM and PP was about half the size of that produced by RO, and in a more advanced stage of recovery...
October 12, 2017: Journal of Cranio-maxillo-facial Surgery
Changfu Li, Ziwu Ji, Jianfei Li, Mingsheng Xu, Hongdi Xiao, Xiangang Xu
Two InGaN/GaN multiple quantum well (MQW)-based blue light emitting diodes (LEDs) emitting photons at approximately the same wavelength, with different indium contents and well widths, are prepared, and the temperature-dependences of their electroluminescence (EL) spectra at different fixed injection currents are investigated. The results show that, compared with sample B with its lower indium content and larger well width, sample A with its higher indium content and smaller well width, has a stronger carrier localization effect and higher external quantum efficiency (EQE) at the lower fixed currents; however, upon increasing the injection current, both the localization effect and EQE for sample A decrease at a faster rate...
November 10, 2017: Scientific Reports
Yan Zhang, Mengying Xie, Vana Adamaki, Hamideh Khanbareh, Chris R Bowen
Energy harvesting is a topic of intense interest that aims to convert ambient forms of energy such as mechanical motion, light and heat, which are otherwise wasted, into useful energy. In many cases the energy harvester or nanogenerator converts motion, heat or light into electrical energy, which is subsequently rectified and stored within capacitors for applications such as wireless and self-powered sensors or low-power electronics. This review covers the new and emerging area that aims to directly couple energy harvesting materials and devices with electro-chemical systems...
November 10, 2017: Chemical Society Reviews
Che Liu, Yanling Guo
The fact that piezoelectric ceramic transducer (PZT) precision drive systems in 3D printing are faced with nonlinear problems with respect to positioning, such as hysteresis and creep, has had an extremely negative impact on the precision of laser focusing systems. To eliminate the impact of PZT nonlinearity during precision drive movement, mathematical modeling and theoretical analyses of each module comprising the system were carried out in this study, a micro-displacement measurement circuit based on Position Sensitive Detector (PSD) is constructed, followed by the establishment of system closed-loop control and creep control models...
November 8, 2017: Sensors
V N Stavrou
Detailed realistic calculations of the spin-flip time (T 1) for an electron in a self-assembled quantum dot (SAQD) due to emission of an acoustic phonon, using only bulk properties with no fitting parameters, are presented. Ellipsoidal lens shaped [Formula: see text] [Formula: see text]As quantum dots, with electronic states calculated using 8-band strain dependent [Formula: see text] theory, are considered. The phonons are treated as bulk acoustic phonons coupled to the electron by both deformation potential and piezoelectric interactions...
November 8, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
Marco Laurenti, Valentina Cauda
This review focuses on the most recent applications of zinc oxide (ZnO) nanostructures for tissue engineering. ZnO is one of the most investigated metal oxides, thanks to its multifunctional properties coupled with the ease of preparing various morphologies, such as nanowires, nanorods, and nanoparticles. Most ZnO applications are based on its semiconducting, catalytic and piezoelectric properties. However, several works have highlighted that ZnO nanostructures may successfully promote the growth, proliferation and differentiation of several cell lines, in combination with the rise of promising antibacterial activities...
November 6, 2017: Nanomaterials
Hongyuan Zhao, Shuangqing Fan, Yan Chen, Zhihong Feng, Hao Zhang, Wei Pang, Daihua Zhang, Menglun Zhang
In this work, we presented a thin-film piezoelectric acoustic gas sensor with enhanced sensitivity by a surface modification strategy of oxygen plasma treated graphene oxide (GO) functionalization. By exposing to ammonia vapor (NH3) of various concentrations at controlled temperature and humidity, the characteristics of the GO-coated acoustic sensor were investigated, that is, sensitivity, linearity, response, and recovery time. Oxygen plasma treatment of the GO-coated sensor further enhanced the sensitivity compared with the freshly prepared GO-coated sensor...
November 13, 2017: ACS Applied Materials & Interfaces
Xiaoliang Chen, Kaushik Parida, Jiangxin Wang, Jiaqing Xiong, Meng-Fang Lin, Jinyou Shao, Pooi-See Lee
Smart sensing electronic device with good transparency, high stretchability and self-powered sensing characteristics are essential in wearable health monitoring systems. This paper innovatively proposes a stretchable nanocomposite nanogenerator with good transparency that can be conformally attached on human body to harvest biomechanical energy and monitor physiological signals. The work reports an innovative device that uses sprayed silver nanowires as transparent electrodes and sandwiches a nanocomposite of piezoelectric BaTiO3 and PDMS as the sensing layer, which exhibits good transparency and mechanical transformability with stretchable, foldable, and twistable properties...
November 7, 2017: ACS Applied Materials & Interfaces
Sunil Kishore Chakrapani, Alexander Howard, Daniel Barnard
The current article reports on the experimental study of the influence of surface roughness on the measurement of the acoustic nonlinearity parameter. The nonlinearity parameter was measured using contact piezoelectric transducers, which were calibrated using the reciprocity based technique. Aluminum and steel samples were chosen to study the influence of hardness of the sample on the measurement of the nonlinearity parameter. While, lower Ra value (average asperity height) aluminum samples were more susceptible to surface deformation and scratches from coupling the transducer to the sample, the same could not be observed for steel samples...
October 28, 2017: Ultrasonics
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"