scholarly journals Fabrication procedure for the adiabatic surface thermometer. [Uses differential thermocouple and heater]

1977 ◽  
Author(s):  
G.R. Dittbenner ◽  
H.S. Jr. Freynik
Keyword(s):  
Differential Thermocouple ◽  
Fabrication Procedure ◽  
Adiabatic Surface

scholarly journals Photostable and Uniform CH3NH3PbI3 Perovskite Film Prepared via Stoichiometric Modification and Solvent Engineering

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 405
Author(s):  
Daocheng Hong ◽  
Mingyi Xie ◽  
Yuxi Tian
Keyword(s):  
Solar Cells ◽  
Optoelectronic Devices ◽  
Solvent Engineering ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Coverage Ratio ◽  
Fabrication Procedure ◽  
Fabrication Condition ◽  
Halide Perovskites ◽  
Photoluminescence Efficiency

Solution-processed organometal halide perovskites (OMHPs) have been widely used in optoelectronic devices, and have exhibited brilliant performance. One of their generally recognized advantages is their easy fabrication procedure. However, such a procedure also brings uncertainty about the opto-electric properties of the final samples and devices, including morphology, stability, coverage ratio, and defect concentration. Normally, one needs to find a balanced condition, because there is a competitive relation between these parameters. In this work, we fabricated CH3NH3PbI3 films by carefully changing the ratio of the PbI2 to CH3NH3I, and found that the stoichiometric and solvent engineering not only determined the photoluminescence efficiency and defects in the materials, but also affected the photostability, morphology, and coverage ratio. Combining solvent engineering and the substitution of PbI2 by Pb(Ac)2, we obtained an optimized fabrication condition, providing uniform CH3NH3PbI3 films with both high photoluminescence efficiency and high photostability under either I-rich or Pb-rich conditions. These results provide an optimized fabrication procedure for CH3NH3PbI3 and other OMHP films, which is crucial for the performance of perovskite-based solar cells and light emitting devices.

scholarly journals Investigation into the Structural, Chemical and High Mechanical Reforms in B4C with Graphene Composite Material Substitution for Potential Shielding Frame Applications

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1921
Author(s):  
Ibrahim M. Alarifi
Keyword(s):  
Composite Material ◽  
Melting Point ◽  
Boron Carbide ◽  
High Strength ◽  
Stir Casting ◽  
High Fracture Toughness ◽  
Chemical Compositions ◽  
High Fracture ◽  
Fabrication Procedure ◽  
Standard Designs

In this work, boron carbide and graphene nanoparticle composite material (B4C–G) was investigated using an experimental approach. The composite material prepared with the two-step stir casting method showed significant hardness and high melting point attributes. Scanning electron microscopy (SEM), along with energy dispersive X-ray spectroscopy (EDS) analysis, indicated 83.65%, 17.32%, and 97.00% of boron carbide + 0% graphene nanoparticles chemical compositions for the C-atom, Al-atom, and B4C in the compound studied, respectively. The physical properties of all samples’ B4C–G like density and melting point were 2.4 g/cm3 density and 2450 °C, respectively, while the grain size of B4C–G was in the range of 0.8 ± 0.2 µm. XRD, FTIR, and Raman spectroscopic analysis was also performed to investigate the chemical compositions of the B4C–G composite. The molding press composite machine was a fabrication procedure that resulted in the formation of outstanding materials by utilizing the sintering process, including heating and pressing the materials. For mechanical properties, high fracture toughness and tensile strength of B4C–G composites were analyzed according to ASTM standard designs. The detailed analysis has shown that with 6% graphene content in B4C, the composite material portrays a high strength of 134 MPa and outstanding hardness properties. Based on these findings, it is suggested that the composite materials studied exhibit novel features suitable for use in the application of shielding frames.

scholarly journals Direct coherent multi-ink printing of fabric supercapacitors

2021 ◽  
Vol 7 (3) ◽  
pp. eabd6978 ◽  
Author(s):  
Jingxin Zhao ◽  
Hongyu Lu ◽  
Yan Zhang ◽  
Shixiong Yu ◽  
Oleksandr I. Malyi ◽  
...  
Keyword(s):  
System Integration ◽  
High Performance ◽  
Mechanical Stability ◽  
Three Dimensional ◽  
High Mass ◽  
Wearable Electronics ◽  
Energy Storage Devices ◽  
Fabrication Procedure ◽  
Self Powered ◽  
Mechanical Devices

Coaxial fiber-shaped supercapacitors with short charge carrier diffusion paths are highly desirable as high-performance energy storage devices for wearable electronics. However, the traditional approaches based on the multistep fabrication processes for constructing the fiber-shaped energy device still encounter persistent restrictions in fabrication procedure, scalability, and mechanical durability. To overcome this critical challenge, an all-in-one coaxial fiber-shaped asymmetric supercapacitor (FASC) device is realized by a direct coherent multi-ink writing three-dimensional printing technology via designing the internal structure of the coaxial needles and regulating the rheological property and the feed rates of the multi-ink. Benefitting from the compact coaxial structure, the FASC device delivers a superior areal energy/power density at a high mass loading, and outstanding mechanical stability. As a conceptual exhibition for system integration, the FASC device is integrated with mechanical units and pressure sensor to realize high-performance self-powered mechanical devices and monitoring systems, respectively.

scholarly journals Fabrication of Small-Pixel CdZnTe Sensors and Characterization with X-rays

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 2932
Author(s):  
Stergios Tsigaridas ◽  
Silvia Zanettini ◽  
Manuele Bettelli ◽  
Nicola Sarzi Amadè ◽  
Davide Calestani ◽  
...  
Keyword(s):  
Direct Detection ◽  
X Rays ◽  
Single Chip ◽  
Low Leakage ◽  
Low Leakage Current ◽  
Fine Pitch ◽  
Pixel Sensors ◽  
Fabrication Procedure ◽  
Vertical Bridgman ◽  
Stable Performance

Over the past few years, sensors made from high-Z compound semiconductors have attracted quite some attention for use in applications which require the direct detection of X-rays in the energy range 30–100 keV. One of the candidate materials with promising properties is cadmium zinc telluride (CdZnTe). In the context of this article, we have developed pixelated sensors from CdZnTe crystals grown by Boron oxide encapsulated vertical Bridgman technique. We demonstrate the successful fabrication of CdZnTe pixel sensors with a fine pitch of 55 m and thickness of 1 mm and 2 mm. The sensors were bonded on Timepix readout chips to evaluate their response to X-rays provided by conventional sources. Despite the issues related to single-chip fabrication procedure, reasonable uniformity was achieved along with low leakage current values at room temperature. In addition, the sensors show stable performance over time at moderate incoming fluxes, below 106 photons mm−2s−1.

scholarly journals A Peristaltic Micropump Based on the Fast Electrochemical Actuator: Design, Fabrication, and Preliminary Testing

Actuators ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 62
Author(s):  
Ilia Uvarov ◽  
Pavel Shlepakov ◽  
Artem Melenev ◽  
Kechun Ma ◽  
Vitaly Svetovoy ◽  
...  
Keyword(s):  
High Performance ◽  
Drug Delivery Systems ◽  
Main Part ◽  
Fabrication Technology ◽  
Fabrication Procedure ◽  
Order Of Magnitude ◽  
Peristaltic Micropump ◽  
Biomedical Field ◽  
Lift Off ◽  
Actuator Design

Microfluidic devices providing an accurate delivery of fluids at required rates are of considerable interest, especially for the biomedical field. The progress is limited by the lack of micropumps, which are compact, have high performance, and are compatible with standard microfabrication. This paper describes a micropump based on a new driving principle. The pump contains three membrane actuators operating peristaltically. The actuators are driven by nanobubbles of hydrogen and oxygen, which are generated in the chamber by a series of short voltage pulses of alternating polarity applied to the electrodes. This process guaranties the response time of the actuators to be much shorter than that of any other electrochemical device. The main part of the pump has a size of about 3 mm, which is an order of magnitude smaller in comparison with conventional micropumps. The pump is fabricated in glass and silicon wafers using standard cleanroom processes. The channels are formed in SU-8 photoresist and the membrane is made of SiNx. The channels are sealed by two processes of bonding between SU-8 and SiNx. Functionality of the channels and membranes is demonstrated. A defect of electrodes related to the lift-off fabrication procedure did not allow a demonstration of the pumping process although a flow rate of 1.5 µl/min and dosage accuracy of 0.25 nl are expected. The working characteristics of the pump make it attractive for the use in portable drug delivery systems, but the fabrication technology must be improved.

Facile Fabrication Procedure for C60-Doped Silicon Oxide Thin Films

1997 ◽  
Vol 26 (10) ◽  
pp. 995-996 ◽  
Author(s):  
Isao Hasegawa ◽  
Koji Shibusa ◽  
Satoshi Kobayashi ◽  
Shuichi Nonomura ◽  
Shoji Nitta
Keyword(s):  
Thin Films ◽  
Silicon Oxide ◽  
Oxide Thin Films ◽  
Doped Silicon ◽  
Fabrication Procedure ◽  
Facile Fabrication

Studies of the Conditions Affecting the Vulcanization of Rubber. V. The Effect of Accelerators on the Heat of Vulcanization

1931 ◽  
Vol 4 (2) ◽  
pp. 190-190
Author(s):  
Y. Toyabe
Keyword(s):  
Total Sulfur ◽  
Micellar Structure ◽  
Rubber Compounds ◽  
Chemical Combination ◽  
Differential Thermocouple ◽  
The Times

Abstract The heat of vulcanization of rubber compounds containing various quantities of sulfur and several organic vulcanization accelerators were traced by means of a differential thermocouple during the vulcanization. The profiles of the heating curves were similar to those obtained in the case of unaccelerated compounds, but the temperature maxima appeared sooner with accelerated than with unaccelerated compounds. The vulcanizates corresponding to the temperature-maxima were analyzed chemically by ordinary methods and the ratios of the free to total sulfur were calculated. They vary a little from 50 per cent, and show that the extent of sulfur combination is not much different from that with unaccelerated compounds. The accelerators tested were hexamethylenetetramine, aldehyde-ammonia diphenylguanidine, di-o-tolylguanidine, p-nitrosodimethylaniline, thiocarbanilide, “Vulkacit P”, “Vulkacit PX”, “Vulkacit M”, and tetramethylthiuramdisulfide The results of the experiments show that these accelerators promote the disaggregation of the micellar structure of rubber (as shown in reports II and III 0. this work) before chemical combination of rubber and sulfur occurs. By thus making the single micelle of rubber smaller, they increase the number of chemical units of rubber coming into reaction with sulfur; i. e., the probability of combination of rubber and sulfur becomes greater. The times for the temperature maxima to appear in the experiments above, which are shortened by accelerators, show that this theory holds good, when it is considered that the temperature maxima correspond to the disaggregation maxima of the rubber hydrocarbon under consideration.

Basic Studies for the Automatic Fabrication of Welded Built-up Beams

1995 ◽  
Vol 11 (02) ◽  
pp. 111-116 ◽  
Author(s):  
Chang Doo Jang ◽  
Seung II Seo
Keyword(s):  
Welding Current ◽  
Simulation Method ◽  
Welding Deformation ◽  
Skilled Workers ◽  
Fabrication Cost ◽  
Current Voltage ◽  
Fabrication Procedure ◽  
Increase In Productivity ◽  
Study Techniques ◽  
Basic Studies

In the fabrication of welded built-up beams, longitudinal deformation occurs due to welding. As it prevents improvement of productivity and quality, heating for straightening the welding deformation is necessary. Therefore, control of the deformation due to welding and heating is the base for the automatic fabrication of built-up beams. In this study, techniques to control the deformation are developed. Based on the simple formulas for estimation of the deformation proposed in the previous study, a procedure to calculate the required reverse curvatures to straighten the welding deformation is presented and a method to simulate the fabrication procedure is developed. From the simulation of the fabrication procedure it is concluded that, in heating for straightening, deep-heated depth is more economical than wide-heated breadth in yielding the same curvature. To apply the results obtained to automatic fabrication, welding and heating parameters such as welding current, voltage and speed, and heated depth and breadth are selected and fabrication cost is expressed by the parameters, which are optimized under the constraints. According to the optimized results, the higher welding current reduces the fabrication cost. Results obtained through executing the simulation method described herein can be used in the guidance of welding and heating procedures instead of depending on the experience of skilled workers--and this can contribute to an increase in productivity and quality.

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