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马志超 ' target='_blank'> 廉玉广 ' target='_blank'> 牟义 ' target='_blank'> 李江华 ' target='_blank'> 邱浩 ' target='_blank'> 王克南 陈健强 ' target='_blank'> 《中州煤炭》2020,(12):106-111
选取晋城矿区典型3号无烟煤试样,在实验室进行单轴加载条件下的电阻率测试实验,并开展矿井瞬变电磁法探测不含水断层现场试验,研究了不含水断层的视电阻率变化特征。结果表明:煤样加载全过程,经过压密阶段、弹性变形阶段、塑性变形阶段、峰值后破裂阶段、残余变形阶段5个阶段;煤样应力应变曲线表现为由低到高再到低的特征,煤样电阻率曲线表现为由高到低再到高的特征;加载过程中,压密阶段、弹性变形阶段应力越大电阻率越小,应力为影响电阻率变化的主控因素;塑性变形阶段,电阻率先减小后增大,应力和裂隙共同影响电阻率变化,由应力为主要因素逐渐转变到裂隙为主要因素;峰值后破裂阶段和残余变形阶段电阻率急速增大,裂隙为影响电阻率变化的主控因素;通过瞬变电磁法探测不含水断层试验,发现不含水断层导致视电阻率明显升高,表明裂隙为影响断层视电阻率单一变化的主要因素。 相似文献
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Yeliz Yildirim Zafer GonulalanSebnem Pamuk Nurhan Ertas 《Food research international (Ottawa, Ont.)》2011,44(3):725-728
The current study was carried out to detect Salmonella spp. contamination on chicken carcasses and to determine the antibiotic susceptibility profiles and serotype distribution of the isolates. A total of 200 packaged fresh raw chicken samples sold at retail in different markets in central Anatolia were analysed between April 2005 and March 2006. Salmonella spp. was detected in 34% (68/200) of samples using cultural technique and were confirmed by PCR. Ten Salmonella serovars were identified; predominant ones included Typhimurium, Infantis and Heidelberg. All of the Salmonella spp. isolates tested, exhibited resistance to one or more antimicrobial agents used. Resistance to penicillin, oxacillin, clindamycin, vancomycin, erythromycin and ampicillin were evident 100%, 97%, 97%, 92.6%, 89.7% and 85.2%, respectively. Also resistance to tetracycline (67.6%), streptomycin (61.7%), neomycin (55.8%) and cephalothin (52.9%) was observed but a small percentage of the isolates demonstrated resistance to gentamicin (14.7%), chloramphenicol (10.2%), cefotaxime (2.9%) and amikacin (2.9%). As a result, high prevalence of Salmonella spp. and the relatively high resistance among the bacteria tested could pose public health and therapeutic problems in consumers as potential vehicle of resistant Salmonella foodborne infections. To avoid Salmonella contamination, hygienic rules of slaughter and poultry meat processing must be rigorously observed and antibiotic use must be controlled by governmental agencies to prevent increased resistance of antibiotics. 相似文献
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电机电流分析法在机床类设备诊断中的应用研究 总被引:2,自引:0,他引:2
机床类设备传动链复杂,结构紧凑且封闭,对传动系统状态监测一直没有有效的分析办法,即使在噪声增大等恶劣情况下,常规的振动诊断方法也难以奏效.本文尝试用电流信号分析法,简称MCSA(Motor Current Signal Analysis),对机床状态进行测试和分析.通过电机电流信号的传动链齿轮谱特征分析,对其做出了正确评估,表明定子电流能很好地反映机床传动系统部件的运行状况.同时进行了多种运行工况的测试与试验,研究结论对机床类设备的生产制造和现场运行状态的分析提供了有效依据. 相似文献
25.
Selçuk Yildirim Bettina Röcker Marit Kvalvåg Pettersen Julie Nilsen‐Nygaard Zehra Ayhan Ramune Rutkaite Tanja Radusin Patrycja Suminska Begonya Marcos Véronique Coma 《Comprehensive Reviews in Food Science and Food Safety》2018,17(1):165-199
The traditional role of food packaging is continuing to evolve in response to changing market needs. Current drivers such as consumer's demand for safer, “healthier,” and higher‐quality foods, ideally with a long shelf‐life; the demand for convenient and transparent packaging, and the preference for more sustainable packaging materials, have led to the development of new packaging technologies, such as active packaging (AP). As defined in the European regulation (EC) No 450/2009, AP systems are designed to “deliberately incorporate components that would release or absorb substances into or from the packaged food or the environment surrounding the food.” Active packaging materials are thereby “intended to extend the shelf‐life or to maintain or improve the condition of packaged food.” Although extensive research on AP technologies is being undertaken, many of these technologies have not yet been implemented successfully in commercial food packaging systems. Broad communication of their benefits in food product applications will facilitate the successful development and market introduction. In this review, an overview of AP technologies, such as antimicrobial, antioxidant or carbon dioxide‐releasing systems, and systems absorbing oxygen, moisture or ethylene, is provided, and, in particular, scientific publications illustrating the benefits of such technologies for specific food products are reviewed. Furthermore, the challenges in applying such AP technologies to food systems and the anticipated direction of future developments are discussed. This review will provide food and packaging scientists with a thorough understanding of the benefits of AP technologies when applied to specific foods and hence can assist in accelerating commercial adoption. 相似文献
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Bin Wang Xin Zhang Hongliang Huang Zhangjing Zhang Taner Yildirim Wei Zhou Shengchang Xiang Banglin Chen 《Nano Research》2021,14(2):507-511
We report a microporous aluminum-based metal-organic framework(MOF),BUT-22 for high methane(CH4),hydrogen(H2),and carbon dioxide(CO2)storage.At 296 K and 80 bar,BUT-22 exhibits a high gravimetric CH4 storage capacity of 530 cm3(STP)/g(0.379 g/g).BUT-22 also has a high gravimetric H2storage capacity of 12 wt.%at 100 bar and 77 K.In addition,the CO2adsorption studies revealed that BUT-22 exhibits a high absolute gravimetric CO2 uptake of 1.7 g/g at 296 K and 40 bar. 相似文献
30.
M. Erdem Günay Fatma AkpinarZ. Ilsen Onsan Ramazan Yildirim 《International Journal of Hydrogen Energy》2012
The water gas shift activity of promoted Pt–CeO2/Al2O3 catalysts were investigated in this work. The catalysts were prepared by incipient to wetness impregnation and tested using a microflow reaction system. It was found that K has beneficial effects under product-containing feed compositions while Co and Ni promoters worsen catalyst performance. The reaction temperature and feed H2O/CO ratio positively affect the catalytic activity, whereas CO2 and H2 addition to the feed decreases CO conversion, as expected. The experimental results were also modeled using modular neural networks, at which the catalyst preparation and operational (reaction) variables were used together in the same network because they are interacting but processed differently because they are dissimilar in their form (i.e. categorical versus continuous) and their effects on catalytic activity. It was concluded that the effects of catalyst preparation and operational variables and their relative importance could be comprehended more accurately by using this approach, which may be also employed in other similar systems. 相似文献