In this paper, a flexible microrobot actuated by acoustic wave is proposed. The microrobot has two flexible sharp tails, the flexible sharp tails oscillate actuated with an external acoustic field and thus generates acoustically streaming to drive the microrobot. By adjusting the actuated frequency of acoustic waves, the motion direction of the microrobot can be regulated. The simulation model of the microrobot is established with software of COMSOL Multiphysics 6.0, the characteristic modes of the microrobot are analysed and its reference actuated frequency are obtained. In addition, the acoustic actuated microrobot simulation model is established to analyse the relationship between the acoustic wave actuated frequency and the harmonic displacement and normal acceleration of the microrobot. Taking the reference actuated frequency as the datum frequency, the acoustic actuated frequencies of the left turning, the right turning and the approximate linear motion modes of the microrobot are optimally obtained.
The design basis of optical path control of micro optical-electro mechanical fuze safety and arming system is insufficient. Based on working principle of the S&A, the basic theory of laser transmission in optical fibre was analysed, and the simulation model and experiment system of dual fibre alignment were established, which by the laser energy transfer characteristics of the S&A were studied. The results showed that radial deviation and angle deviation were main factors causing the loss of laser energy transmission during fibre coupling, and the radial deviation larger than 25 μm or the angle deviation larger than 2.1° should be avoided. The energy transmission properties would not be affected by radial deviation and angle deviation when the axial clearance was less than 100 μm. And the energy transmission efficiency would be significantly reduced with the influence of multiple factors such as axial, radial and angular deviation, which among the angle deviation was main factor. In the process of optical path designing for S&A system, ensuring the angle alignment of fibres is most important, and the angle deviation larger than 1° should be avoided when the radial offset is superimposed.
Investigating the cooling and lubrication effects of MWCNTs-based nanofluids with surfactants in reducing cutting force and surface roughness compared to dry and wet is the main focus of this study. Besides this, searching out the optimal settings of process parameters including cutting speed, feed rate, depth of cut, and cutting environment in milling Ti-6Al-4V alloy is another prime objective. Box-Behnken design (BBD)-based response surface methodology was employed for experimental design. To predict the chosen responses, quadratic models were developed. Analysis of variance (ANOVA) results showed that the cutting environment has the highest significance, with a variation in cutting force and roughness of about 76.5% and 49.9%, respectively. Both responses were lowered significantly in nanoMQL over wet. Optimisation using the composite desirability approach results that 32 m/min cutting speed, 22 mm/min table feed, 0.75 mm depth of cut, and NanoMQL were the optimal solution within the selected boundary constraints.
A novel ultra-thin and high toughness piezoelectric thin film sensor based on MEMS technology is designed. The sensor uses ultra-thin SiO2/SiN as the main cantilever support material, piezoelectric thin film as the sensitive material, and uses piezoelectric effect to measure acceleration. Aiming at the problems of poor reliability and large stress release of ultra-thin piezoelectric cantilever films, the structural design, simulation and technological scheme design of multilayer films were carried out. Finally, the device is manufactured and tested. The test results show that the new ultra-thin and high toughness piezoelectric thin film sensor based on MEMS technology has a resonant frequency of 4 KHz, a sensitivity of 6.66 mV/g, and good linearity, which can be applied to acceleration, vibration sensors and other fields.
As a kind of special drugs, antibiotics are widely used in the treatment of animal infectious diseases, which lead to their accumulation in food and harm to human health. Traditional antibiotic detection methods have disadvantages such as cumbersome steps, high cost and poor practicability. Therefore, it is particularly important to develop a simple and rapid detection method. Hence, a molybdenum disulphide composite fluorescent probe was designed, synthesised, and applied to the detection of oxytetracycline. Good results were obtained in the practical samples.
Piezo-stack actuators are widely used in micro-displacement mechanisms due to their high accuracy, small size and high output force. Analysing the output characteristics of piezo-stack actuators is an important step to ensure the high precision of micro-displacement mechanism. In this paper, a test device for output characteristics of piezo-stack actuators driving high stiffness loads is designed, and a new piezo-stack actuator preload mechanism is proposed. The simulation results verify the proposed stiffness model and dynamic model of the test device. When the same preload force was applied to the piezo-stack actuators and the frequency of driving voltage increases, the displacement amplitude of the piezo-stack actuators does not change significantly, but the hysteresis loop becomes significantly larger and the hysteresis increases. When the preload force is increased with constant voltage frequency, the output displacement of the piezo-stack actuators increases significantly at first, but decreases when the preload force exceeds a certain threshold, about 20 MPa. In this case, the hysteresis loop becomes larger and the hysteresis increases.
This presents paper the data authentication protocol (DAP) of the autonomic reflective middleware for the management of NANOdevices (ARMNANO) architecture, which is capable of the detection of outliers in nanodata. DAP is composed of two modules; the first one consists of typical statistical metrics on a variable, to be used in a second module based on a maximum likelihood estimation (MLE) to learn its distribution model. We found excellent results in three case studies where the context of application consisted of a nanosensor (NS) array in an epifluorescence microscope that monitors a neuromodulator, the serotonine (also called 5-hydroxytriptamine). In the first and second cases, we evaluate the top saturation point of the NS as a function of the type of NS and type of buffer, finding the zones of maximum authentication, while in the third case is assessed a time series nanodata of NS measuring 5-hydroxytriptamine in a dynamic flow system. Thus, we evaluated our nanodata authentication approach in a dynamic system with encouraging results.
In order to reduce the firing energy of the exploding foil blasting machine and optimised its performance, the Al/Cu exploding foil transducer element was fabricated by micro-electro-mechanical system (MEMS) technology, and its electric explosion performance and ability to drive the flyer were studied. The results showed that when the charging voltage was 1.3 KV, the energy utilisation rate of the Al/Cu exploding foil was increased by 25% compared with the traditional Cu exploding foil. Compared with the traditional Cu explosive foil initiator, the Al/Cu explosive foil initiator driven flyer speed is faster and the ignition sensitivity is higher.
The traditional strip-line circulator/isolator module is realised by mechanical processing, which is large size and difficult to be installed with micro-assembly process. The miniaturised strip-line circulator/isolator module is realised by the micro-electro-mechanical systems (MEMS) bulk silicon process and the micro-assembly process. Measured within frequency range of 10~18 GHz, the insertion loss between ANT and Tx is less than 0.9 dB, even it can reach 0.4 dB when the return loss is less than -15 dB. The insertion loss between ANT and Rx is mostly less than 1.1 dB except in the frequency band where the return loss seriously deteriorates. It not only has smaller size (about 8 mm * 9 mm * 2.5 mm) to be easily installed with micro-assembly process and can replace the widely used microstrip circulator/isolator module in situ, but also has electromagnetic and magnetostatic shielding advantages.
With the rapid development of portable electronic products, the contradiction between the rapid rise in energy consumption of electronic products and the slow development of battery technology limits the application potential of many electronic devices. Low-power consumption power management chips have become a research hotspot. In this paper, a closed-loop stable LDO circuit structure based on curvature compensation reference is designed using 0.18 μm CMOS process. The designed LDO has high power rejection ratio and small static current, which is suitable for use as a power management chip in portable electronic products.
This paper presents fly cutting surface profile mathematical model using the spindle and guideways kinematic motion errors, as well as cutting parameters. Surface residual height model was firstly established using the feeding velocity, cutting spindle rotational speed and tool tip radius, it indicates that the cutting depth will not affect the surface geometric profile. Surface profile dispersion was carried out using cutter spindle rotation speed and guideways feeding velocity parameters. Guideways kinematic motion errors were introduced into the surface profile model through overlying method, and cutter spindle axial runout error was also introduced by filtering process using filtering convolution operations between the tool tip window filter and guideways kinematic overlapped surface profile. Their mathematical model expressions and illustrations were given, respectively. They were coherent with the cutting experiments results. The proposed model could be used for the surface profile prediction and machine tool error budget.
The self-heating effect occurs when the bulk acoustic wave filter is loaded with power, leading to the deterioration of the insertion loss. In this paper, the self-heating effect of bulk acoustic wave filters at high frequency power is investigated. A test system is built to obtain the maximum surface temperature and the insertion loss of the bulk acoustic wave filter at different power levels. The test results show that the self-heating effect causes the internal temperature of the bulk acoustic wave filter to increase further after increasing the power, resulting in the increase of the insertion loss. The test system and analysis method in this paper verify the relationship between the self-heating effect and the insertion loss, and can provide guidance for the construction of the relevant reliability test system of the bulk acoustic wave filter.
Several lines of treatment for COVID-19 are being used worldwide, but to date, the perfect line of therapy is not available. Nanomedicines received success rates in past in treating various viral complications like HCV, HSV1, IAV, HuNoV, IBV, EBOV and HIV1, which could be a game-changer for COVID-19. Various manufacturing units are looking towards nanotechnology and evaluating different nanomedicines and vaccines for treating corona infection. Recently Pfizer achieved great success in developing liposome-based messenger ribonucleic acid vaccine called BNT162b. There are few nanoparticles (NPs) under clinical trials capable of neutralising SARS-CoV-2 in outer surrounding, e.g., GDs-NPs (Gold nanoparticles), Ag-NPs (Silver nanoparticles), CuO-NPs (Copper oxide nanoparticles). The mutation of virus is challenging for treating COVID-19 and intense discovery in field of nanoscience and clinical manifestation of COVID-19 is required. Authors described the significant role of lipid nanoparticles (LNPs) in different vaccine formulations and their utility in nanomedicines for management of COVID-19.
In order to verify the galvanometer scanning and obtain more accurate scanning effect. According to the scanning trajectory of x-y two-dimensional (2D) galvanometer scanning adopts theoretical analysis and matrix laboratory (Matlab) software simulations, and then discusses the correction method of the scanning distortion graph. The coordinate transformation and software correction is proposed. A result which shows software correction can make up for coordinate transformation with higher measurement accuracy.
The transient effect of nanoparticles is easy to generate transient pulses, which has a great influence on the radiation resistance of integrated circuits. In order to study the conditions of transient effect of nanoparticles, this paper studies the computer simulation of transient pulse characteristics of nanoparticles under high-intensity compression. Combining TCAD simulation with HSPICE simulation test, a new comparative test structure is proposed, which directly quantifies the influence of temperature and voltage on transient pulse by radiation test. The transient current, voltage and TCAD simulation results of nanoparticles, the transient current and voltage of nanoparticles are consistent. When 1.5E = 0.09 s, a transient pulse appears. The peak value of current reaches 0.0010A. When it reaches the highest point, it decreases rapidly. After 1.99E - 0.09 s, it tends to be stable gradually, while the voltage drops to 0V, then increases rapidly, and tends to be stable at 1.99E - 0.09 s. On the pulse width, the HSPICE model simulation results and TCAD simulation which can effectively simulate the transient pulse characteristics of nanoparticles under high-intensity compression, and simulation results show that with the increase of temperature, the transient pulse current and voltage of nanoparticles decrease, when the temperature rises to 480 K, the current and voltage are lower than 180 K.
