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51.
Liu  Haining  Xiu  Chunli  Zhang  Tao  Lu  Yanhui 《Journal of chemical ecology》2022,48(7-8):618-627
Journal of Chemical Ecology - The cotton bollworm, Helicoverpa armigera, is one of the most destructive agricultural pests in the world, infesting cotton, maize, soybean, and many other crops. In...  相似文献   
52.
锂电池是LWD仪器正常工作的动力来源,是仪器的心脏。仪器出井后,需要在井口读取数据,当锂电池的电量接近耗尽时,会导致数据读取失败的问题。该问题处理不当,会造成长期占用井口,影响钻井时效,严重时还可能会因短路造成昂贵的LWD仪器损坏。锂电池的临界电压问题暴露了该仪器的设计缺陷,在此通过技术方法充分利用INSITE系统本身提供的功能,绕过其设计缺陷将问题解决。  相似文献   
53.
Replacement of precious single metal catalysts with cost-effective, highly-dispersed composite catalysts for catalytic hydrothermal conversion of residue holds tremendous promise for the residue upgrading technologies. Organic metals were added to the feed as the oil-soluble precursors, and transformed into the catalytic active phases in this work. Physical properties and structures of the composite catalysts had been investigated by X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope and transmission electron microscopy. The composite catalysts were found to be highly efficient in the catalytic hydrothermal conversion of both model compound and residue. Increased metal dispersion and synergistic effects of two metals played indispensable roles in such catalytic system. Results showed that under the test conditions in the article, the catalyst had the best catalytic performance when the mass ratio of molybdenum to iron was 1.5.  相似文献   
54.
Journal of Infrared, Millimeter, and Terahertz Waves - Terahertz radiation has many unique characteristics that make it useful for noninvasive mail inspection. While qualitative analysis of mail...  相似文献   
55.
魏明  倪涛 《现代导航》2021,12(5):379-381
通过将开口环谐振器结构应用到微带准八木天线的设计中,将一个开口环谐振器结构与八木天线的有源振子相结合,振子的两臂可以作为开口环谐振器结构具有开口的外环,从而使所设计的八木天线具有双频特性。其中低频谐振由微带准八木天线结构产生,高频由单个开口环谐振器结构产生。由仿真和分析结果可知,所设计天线在低频和高频两个谐振点均具有很好的端射特性。  相似文献   
56.
Anti-washout and tissue adhesion properties are essential for the clinical application of injectable bone materials. In this study, we prepared calcium phosphate cement (CPC) with anti-washout and tissue adhesion properties and attempted to build covalent bonds between CPC and the amino groups in bone tissue under a self-regulating pH system in the CPC (acidic to basic). The results of push-out tests demonstrated that a significant enhancement (from 6.42 ± 0.76 N to 61.5 ± 4.09 N) in tissue adhesion was obtained with the addition of 6% (w/w) oxidized sodium alginate (OSA) in CPC. The FTIR, XRD, anti-washout test, XPS, pH test, and SEM results suggested that the synergistic effect of OSA-citric acid (CA) led to the formation of a three-dimensional gel network structure in the CPC, and the Schiff base reaction between aldehyde and amino groups induced adhesion between CPC and the bone tissue. Further, the addition of less OSA had no significant negative effect on the hydration properties of CPC. Our work aims to promote the development of injectable bone material in clinical applications.  相似文献   
57.
Zhang  Jiawei  Li  Chen  Rahaman  Md Mamunur  Yao  Yudong  Ma  Pingli  Zhang  Jinghua  Zhao  Xin  Jiang  Tao  Grzegorzek  Marcin 《Artificial Intelligence Review》2022,55(4):2875-2944

Microorganisms such as bacteria and fungi play essential roles in many application fields, like biotechnique, medical technique and industrial domain. Microorganism counting techniques are crucial in microorganism analysis, helping biologists and related researchers quantitatively analyze the microorganisms and calculate their characteristics, such as biomass concentration and biological activity. However, traditional microorganism manual counting methods, such as plate counting method, hemocytometry and turbidimetry, are time-consuming, subjective and need complex operations, which are difficult to be applied in large-scale applications. In order to improve this situation, image analysis is applied for microorganism counting since the 1980s, which consists of digital image processing, image segmentation, image classification and suchlike. Image analysis-based microorganism counting methods are efficient comparing with traditional plate counting methods. In this article, we have studied the development of microorganism counting methods using digital image analysis. Firstly, the microorganisms are grouped as bacteria and other microorganisms. Then, the related articles are summarized based on image segmentation methods. Each part of the article is reviewed by methodologies. Moreover, commonly used image processing methods for microorganism counting are summarized and analyzed to find common technological points. More than 144 papers are outlined in this article. In conclusion, this paper provides new ideas for the future development trend of microorganism counting, and provides systematic suggestions for implementing integrated microorganism counting systems in the future. Researchers in other fields can refer to the techniques analyzed in this paper.

  相似文献   
58.
建立了一种电位滴定法测定氟化钠含量的方法。该方法采用氢氧化钠降解氟硅酸钠与硝酸镧作为滴定剂,以氟离子选择电极为测量电极,测定总氟含量;扣除氟硅酸钠含量,获得氟化钠含量。结果表明,加标回收率范围为99.02%~99.79%,RSD(n=9)为0.24%,样品测定准确度与精密度良好。该方法简化了前处理操作步骤,减少了目视判断终点带来的误差,降低试验过程的毒性,提高了氟化钠含量的检测效率,可作为《HG/T 5210—2017牙膏用氟化钠》补充分析方法。  相似文献   
59.
本文首先从感觉学(即美学)层面探讨了“丑陋”的研究历史,阐释“丑陋”的内涵变化历程。其后,本文总 结出感觉学上的“丑陋”的多重意义。从三个方面来讨论丑陋建筑的判断的标准,并对建筑畅言网的丑陋建筑标 准进行了分析。最后指出丑陋建筑应发挥批判功能,促进建筑学发展与普及。  相似文献   
60.
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