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为顺利过12704工作面夹矸变化带区域,在中厚煤层一次采全高开采工艺过程中,采用了中深孔松动爆破工艺,顺利通过长度180 m夹矸区域,节约工期88 d,有效地保证了12704工作面的正常回采。 相似文献
74.
Kosuke Sato Akihiko Kono Hiroaki Urushibata Yoji Fujita Masato Koyama 《Electrical Engineering in Japan》2019,208(3-4):48-63
The authors developed a physics‐based equivalent circuit model of a lithium‐ion battery (LIB) whose parameters are continually updated, reflecting the theoretical calculation results of the Butler‐Volmer equation, diffusion equations of the lithium‐ion and lithium, and Nernst equations of the liquid and solid phases. The developed model was applied to the charge/discharge simulations of an LIB, and the experimental and simulated results of constant current discharges and pulsed‐charge/discharge were found to be in excellent agreement. In particular, using the developed model, analyzing transient responses of the LIB derived from the transition of the electric double layer charging to the electrode reaction is possible. These results demonstrate that the electrochemical performance of an LIB can be calculated on a circuit simulator using the developed model. 相似文献
75.
To solve the problem of large area and high power consumption of the traditional multi-channel charge readout circuit for X-ray detection,a new multi-channel charge readout circuit structure is presented.The circuit integrates 32 charge acquisition channels,including an integrator,a differential output buffer,a digital control logic circuit and other functional modules.The proposed structure reduces the power consumption and area by integrating the sample and hold circuit and the correlated double sampling circuit into the output buffer.In order to reduce the offset and low-frequency noise,the correlated double sampling technology has been adopted.In addition,the way of overlapping the outputs between the even and odd channels is adopted to realize continuous transmission of the multi-channel signals.The chip has been fabricated using the CMOS 0.25 μm process with the chip size of 2.87 mm×2.68 mm.Measurement results show that the power consumption of each channel is 1.5 mW under the 5.0 V voltage supply and 2.5 V reference voltage.When the integrated capacitor is 7.8 pF,the integration non-linearity is less than 0.1% and the dynamic range reaches 13 100. 相似文献
76.
Lithium disilicate glass-ceramic (LS2) can be biomimetically textured by crystal orientation, mimicking the microstructure of dental enamel and inducing anisotropic mechanical responses to crack growth. The deliberate texturization of LS2 plays to the clinical advantage of reinforcing weak sites of typical fracture initiation in dental prosthetic constructs. Similar to enamel, adhesion of biomimetically textured LS2 could also show anisotropic behavior. Therefore, tensile bond strength (TBS) before and after thermocycling (TC) and interfacial characterization of biomimetically textured LS2 (parallel (PAR) or perpendicular (PER) crystal orientation) after different pre-treatment modes (hydrofluoric acid etching (HFE), grit blasting (GBL) and self-etching glass-ceramic primer (SGP)) were investigated. TC reduced significantly TBS for all specimens except for GBL. Biomimetic textured LS2 after HFE showed anisotropic behavior regarding adhesion. Crystal orientation reduced TBS for the PER HFE specimens after TC significantly. In general, the TBS of HFE specimens was still higher or not significantly lower compared to other pre-treatment modes like GBL or SGP. For the GBL and SGP specimens, crystal orientation had no influence on TBS and interfacial characteristics. In contrast HFE specimens showed different interfacial characteristics depending if they were PAR or PER texturized. Based on these findings, HFE of biomimetic textured LS2 can be recommended. For bonding, the PAR orientation is recommended as its adhesion potential is less prone to degrade. 相似文献
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《全球能源互联网(英文)》2021,4(6):619-630
The technology deployed for lithium-ion battery state of charge (SOC) estimation is an important part of the design of electric vehicle battery management systems. Accurate SOC estimation can forestall excessive charging and discharging of lithium-ion batteries, thereby improving discharge efficiency and extending cycle life. In this study, the key lithium-ion battery SOC estimation technologies are summarized. First, the research status of lithium-ion battery modeling is introduced. Second, the main technologies and difficulties in model parameter identification for lithium-ion batteries are discussed. Third, the development status and advantages and disadvantages of SOC estimation methods are summarized. Finally, the current research problems and prospects for development trends are summarized. 相似文献
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《工程爆破》2022,(3):80-85
介绍了在复杂环境中采用控制爆破技术拆除2组钢筋混凝土结构楼梯扶手,论述了工程方案参数设计及主要安全措施。拟拆除扶手为钢筋混凝土墙体,厚30cm,墙体布置2层钢筋,纵向钢筋为Φ15mm,间距15cm,横向钢筋为Φ12mm,间距20cm,因墙体较薄,钢筋密集,沿墙面水平向钻孔,施工难度大,采取剔除墙端部箍筋,沿墙体垂直钻孔,孔间距30cm,采用不耦合装药结构。扶手墙体不规则,需分区段确定孔深,由于扶手底座混凝土需要保护,孔底填充缓冲材料,采用非电导爆管雷管逐段孔外接力起爆。利用炮被(橡胶轮胎制作)进行覆盖防护,使爆破飞石控制在被爆体周围23m范围内,同时在距被爆体周围2m范围搭设防护排架,铺设竹席、棉被和草帘等进行隔离防护,确保爆破飞散物不飞出防护层外,爆破后达到预期的爆破效果。 相似文献