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The effects of non-thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles ( FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products.  相似文献   
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安俊理 《机械管理开发》2021,36(4):140-141,161
以寺河矿南区回风大巷为工程背景,在分析巷道地质条件的基础上,通过理论计算分析了锚杆及锚索的主要支护参数,并确定了锚杆及锚索的型号;结合以往的生产实践经验,确定了巷道联合支护方案.实践表明,巷道支护方案合理,可以满足安全生产要求.  相似文献   
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Antimony triselenide (Sb2Se3) nanoflake-based nitrogen dioxide (NO2) sensors exhibit a progressive bifunctional gas-sensing performance, with a rapid alarm for hazardous highly concentrated gases, and an advanced memory-type function for low-concentration (<1 ppm) monitoring repeated under potentially fatal exposure. Rectangular and cuboid shaped Sb2Se3 nanoflakes, comprising van der Waals planes with large surface areas and covalent bond planes with small areas, can rapidly detect a wide range of NO2 gas concentrations from 0.1 to 100 ppm. These Sb2Se3 nanoflakes are found to be suitable for physisorption-based gas sensing owing to their anisotropic quasi-2D crystal structure with extremely enlarged van der Waals planes, where they are humidity-insensitive and consequently exhibit an extremely stable baseline current. The Sb2Se3 nanoflake sensor exhibits a room-temperature/low-voltage operation, which is noticeable owing to its low energy consumption and rapid response even under a NO2 gas flow of only 1 ppm. As a result, the Sb2Se3 nanoflake sensor is suitable for the development of a rapid alarm system. Furthermore, the persistent gas-sensing conductivity of the sensor with a slow decaying current can enable the development of a progressive memory-type sensor that retains the previous signal under irregular gas injection at low concentrations.  相似文献   
6.
Tian  Dating  Zhou  Yuchi  An  Kai  Kang  Huiting 《Polymer Bulletin》2020,77(4):1847-1868
Polymer Bulletin - Preparation of konjac glucomannan-grafted poly(trimethyl allyl ammonium chloride) (KGM-g-PTMAAC) was carried out using KGM as polysaccharide matrix and TMAAC as cationic...  相似文献   
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In the future, hydrogen will be an important energy carrier and industrial raw material. Catalytic steam reforming of bio-oils is a promising and economically viable technology for hydrogen production. However, during the reforming process, the catalysts are rapidly deactivated due to coke formation and sintering. Thus, maintaining the activity and stability of catalysts is the key issue in this process. Optimized operation conditions could extend the catalyst lifetime by affecting the coke morphology or promoting coke gasification. This article summarizes the recent developments in the field of catalytic steam reforming of bio-oils, focusing on the operation conditions, the properties of the catalysts, and the effects of the catalyst supports. The expected insights into the catalytic steam reforming of bio-oils will provide further guidance for hydrogen production from bio-oils.  相似文献   
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济阳坳陷下古生界潜山油气藏特征及成藏模式   总被引:1,自引:1,他引:0  
济阳坳陷下古生界潜山具有多样性、复杂性的特点,潜山差异性的形成演化、油气成藏主控因素和控藏模式不明确,严重制约了该区潜山油气勘探。在潜山分类的基础上,综合利用系统恢复、分类对比和典型解剖等方法,揭示了济阳坳陷下古生界不同类型潜山的形成演化过程和油气成藏主控因素差异性,分类建立了油气成藏模式。研究表明,济阳坳陷下古生界主要发育高位新盖侵蚀残丘潜山、中位古盖拉张断块潜山、中位新古盖拉张剪切断块潜山、中位中古盖挤压拉张断块潜山和低位古盖拉张滑脱断块潜山5种潜山类型。不同类型潜山的形成演化和油气成藏各具特色,其中,高位新盖侵蚀残丘潜山的发育受隆升、侵蚀作用控制,油气成藏主要受控于油源和盖层条件,表现为"单向供烃、砂体-不整合岩溶体联合输导、残丘控藏"的成藏模式;中位古盖拉张断块潜山的发育受掀斜、断裂作用控制,油气成藏主要受控于储集条件,表现为"单向供烃、顺向断层输导、反向断层控藏"的成藏模式;中位新古盖拉张剪切断块潜山的发育受反转、翘倾和走滑切割作用控制,油气成藏主要受控于输导条件,表现为"多源供烃、断溶体立体输导、断裂控藏"的成藏模式;中位中古盖挤压拉张断块潜山的形成受强烈挤压、拉张滑脱作用控制,油气成藏主要受控于储集条件,表现为"多源供烃、断缝体输导、断褶控藏"的成藏模式;低位古盖拉张滑脱断块潜山的形成受强烈拉张滑脱作用控制,油气成藏主要受控于输导条件,表现为"顶部供烃、断缝体输导、断裂控藏"的成藏模式。  相似文献   
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A series of anionic conjugated polyelectrolytes (CPEs) is synthesized based on poly(fluorene-co-phenylene) by varying the side-chain ionic density from two to six per repeat units (MPS2-TMA, MPS4-TMA, and MPS6-TMA). The effect of MPS2, 4, 6-TMA as interlayers on top of a hole-extraction layer of poly(bis(4-phenyl)-2,4,6-trimethylphenylamine (PTAA) is investigated in inverted perovskite solar cells (PeSCs). Owing to the improved wettability of perovskites on hydrophobic PTAA with the CPEs, the PeSCs with CPE interlayers demonstrate a significantly enhanced device performance, with negligible device-to-device dependence relative to the reference PeSC without CPEs. By increasing the ionic density in the MPS-TMA interlayers, the wetting, interfacial defect passivation, and crystal growth of the perovskites are significantly improved without increasing the series resistance of the PeSCs. In particular, the open-circuit voltage increases from 1.06 V for the PeSC with MPS2-TMA to 1.11 V for the PeSC with MPS6-TMA. The trap densities of the PeSCs with MPS2,4,6-TMA are further analyzed using frequency-dependent capacitance measurements. Finally, a large-area (1 cm2) PeSC is successfully fabricated with MPS6-TMA, showing a power conversion efficiency of 18.38% with negligible hysteresis and a stable power output under light soaking for 60 s.  相似文献   
10.
Journal of Mechanical Science and Technology - The flow stress increases with the increase in strain rate. This phenomenon is the strain rate effect of plastic deformation. Hopkinson experiment...  相似文献   
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