- 标题
- 摘要
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Reference Ultra Low DC Current Source (ULCS) Between 1 fA and 100pA at TüB?:TAK UME
摘要： We present a programmable ultra low DC current source (ULCS), developed at TüB?TAK UME, from 1 fA up to 100 pA with 100 aA resolution. The principle of the device is based on applying a ramp voltage on standard capacitors with values between 1 pF and 1000 pF. The standard capacitors are kept in a temperature controlled box. The device is fully automated with computer control and can be used to generate any currents with 100 aA resolution in its range.
关键词： ramp voltage,capacitance measurement,DC Low current,uncertainty,temperature control
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Purpose-Built Air Bath for use with NMIA Calculable Cross-Capacitor Measurement Chain
摘要： This paper describes the design of an air bath for maintaining the reference capacitors associated with the new NMIA calculable cross-capacitor measurement system. The air bath is designed to maintain a set temperature in the range 15 °C to 25 °C with a stability of 0.1 mK over the short time periods during which the capacitors are measured.
关键词： temperature control,Capacitance measurement,precision measurements,measurement standards
更新于2025-09-10 09:29:36
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Design and construction of a new dual CHP-type renewable energy power plant based on an improved parabolic trough solar collector and a biofuel generator
摘要： A dual hybrid system, including an improved parabolic trough solar collector (CSP) and a biodiesel generator was designed and constructed in this study. The biodiesel was produced from 1st and 3rd generations of biofuel by means of the heat loss of CSP. In order to increase the efficiency of heat transfer of CSP with a working fluid, an optimization was performed with some nanoparticles in concentrate range of 1500 to 3500 ppm. The results showed that thermal conductivity coefficient of the fluid increased by enhancing the volume percentage. This led to an increase in the outlet temperature from the collector and caused better efficiency of CSP and therefore a better performance of the biodiesel transesterification reactor. However, the best working fluid was consisted of a water-based CuO nanofluid (efficiency of 66.42% and the rate of temperature of 1311.1 °C/min). Due to different outlet temperature, various experiments were conducted to produce fuel from rapeseed oil. The best efficiency results (74.54%) as well as the lowest finished costs (69 cents) occurred at temperature of 60 °C. Then, biodiesel was produced from chlorella oil at this temperature with an efficiency of 81.4% and total production cost of 143 ￠.
关键词： Nanofluid,Temperature control,Transesterification,Parabolic trough solar collector,Biodiesel
更新于2025-09-10 09:29:36
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Preservation of Bone Tissue Integrity with Temperature Control for In Situ SR-MicroCT Experiments
摘要： Digital volume correlation (DVC), combined with in situ synchrotron microcomputed tomography (SR-microCT) mechanics, allows for 3D full-field strain measurement in bone at the tissue level. However, long exposures to SR radiation are known to induce bone damage, and reliable experimental protocols able to preserve tissue properties are still lacking. This study aims to propose a proof-of-concept methodology to retain bone tissue integrity, based on residual strain determination using DVC, by decreasing the environmental temperature during in situ SR-microCT testing. Compact and trabecular bone specimens underwent five consecutive full tomographic data collections either at room temperature or 0 °C. Lowering the temperature seemed to reduce microdamage in trabecular bone but had minimal effect on compact bone. A consistent temperature gradient was measured at each exposure period, and its prolonged effect over time may induce localised collagen denaturation and subsequent damage. DVC provided useful information on irradiation-induced microcrack initiation and propagation. Future work is necessary to apply these findings to in situ SR-microCT mechanical tests, and to establish protocols aiming to minimise the SR irradiation-induced damage of bone.
关键词： temperature control,bone,digital volume correlation,SR-microCT,tissue damage,X-ray radiation
更新于2025-09-10 09:29:36