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71.
在石化行业中,管道、罐体、塔体等介质的监测一直是课题研究热点。基于机器人的石化监测系统采用ARM处理器控制智能移动机器人,深入到人员不便进入的介质中,全方位、多角度监测介质的内部情况,准确地监测重要指标的数据,并能及时对图像、指标等数据进行处理。监测人员可在远离现场的地方查看现场情况,监测灵活、便捷。现场测试准确性高,有很高的推广价值。  相似文献   
72.
Severe lattice distortion is a core effect in the design of multiprincipal element alloys with the aim to enhance yield strength, a key indicator in structural engineering. Yet, the yield strength values of medium‐ and high‐entropy alloys investigated so far do not substantially exceed those of conventional alloys owing to the insufficient utilization of lattice distortion. Here it is shown that a simple VCoNi equiatomic medium‐entropy alloy exhibits a near 1 GPa yield strength and good ductility, outperforming conventional solid‐solution alloys. It is demonstrated that a wide fluctuation of the atomic bond distances in such alloys, i.e., severe lattice distortion, improves both yield stress and its sensitivity to grain size. In addition, the dislocation‐mediated plasticity effectively enhances the strength–ductility relationship by generating nanosized dislocation substructures due to massive pinning. The results demonstrate that severe lattice distortion is a key property for identifying extra‐strong materials for structural engineering applications.  相似文献   
73.
Journal of Mechanical Science and Technology - A multi-robot collaborative towing system fixed on floating base for high load marine work was established in this paper, and its dynamics and...  相似文献   
74.
Xin  Wang  Hong  Xiao  Haiqing  Li  Fei  Liu  Zuqiang  Su  Feng  Tan 《Journal of Mechanical Science and Technology》2021,35(5):2161-2166
Journal of Mechanical Science and Technology - Metal fused-coating additive manufacturing composite variable polarity tungsten inert gas (MFCAM & TIG) has the advantages of low cost and...  相似文献   
75.
Due to the COVID-19 epidemic crisis, students from higher education institutions around the world are forced to participate in comprehensive online curriculums. In such a scenario, it is worth investigating how students perceived their learning outcomes and satisfaction based on this method of teaching and learning online. This study aims to explore the role of six factors, namely, system quality, course design, learner-learner interaction, learner-instructor interaction, learner-content interaction, and self-discipline, on university students' perceived learning outcomes and their effect on student satisfaction with online curricula during the COVID-19 epidemic. A structural equation modelling technique was used to assess survey questionnaires obtained from 457 validated students at a Public University in China. The results demonstrated that these determinants had a positive effect on satisfaction and learning outcomes, whereas learner-instructor interaction had no significant effect. Furthermore, the strongest determinant that affected not only students' satisfaction but also their learning outcomes was the learner-content interaction.  相似文献   
76.
In this study, amaranth flour was used as an ingredient to prepare gluten-free cookies. The production process and attributes of amaranth cookies were characterised, and the potential use of amaranth flour as a functional ingredient was analysed. Cookies exhibited a non-uniform reddish brown colour and a cookie factor ratio of 4.5 ± 0.6. Storage studies indicated that after 3 weeks at room temperature cookies presented slight variations in the texture. Simulated gastrointestinal digestion of this product was able to release peptides capable of exerting potential antithrombotic and antihypertensive activities, IC50 values of 0.22 ± 0.04 and 0.23 ± 0.03 mg mL−1 protein, respectively. This work demonstrates for the first time that food made with amaranth flour exerts potential antithrombotic and antihypertensive activity. In conclusion, these amaranth cookies could be an alternative way of incorporating potentially health beneficial products for people who choose a conscious diet, including coeliac or vegan consumers.  相似文献   
77.
78.
While perfluoroalkyl acids (PFAAs), also known as C8s, are used extensively in textile repellent coatings, concerns have arisen for their carcinogenicity and hazardous effects on the environment. In this study, a novel water-based, nonfluoro, and nanobrush textile repelling agent was prepared by conventional sol–gel chemistry using amorphous fumed silica and n-octyltriethoxysilane as the starting materials. Minimal interaction between the designed repelling agent and marketed water-based resins was confirmed using linear viscosity region (LVR) analysis and asymmetric-flow field-flow fractionation (AF4), suggesting the self-stratification potential of the repelling agent. More specifically, the repelling agent exhibited excellent compatibility and self-stratifying ability with a force-emulsified acrylic-based resin, affording a water contact angle of 104.3° when incorporated at 7% solid content. Performance tests carried out on thermoplastic polyurethane (TPU) revealed excellent adhesion (100/100) of a final formulation, and a significant increase in water contact angle from 80.1° to 103.8° after treatment. In addition, the fouling area after the removal of a submerged sample from a mixture of slurry, polymer, and oil decreased from 48 to 1% when the repelling agent was added. Moreover, the sludge-fouling property remained unchanged after 1000 cycles of abrasion. These findings demonstrate the potential of the described nonfluoro, nanobrush repelling agent as an environmentally safe alternative for use with commercial resins, in turn realizing a fully water-based hydrophobic coating. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48003.  相似文献   
79.
为了研究废水中有机物的去除问题,针对某企业含有机物废水进行了对比试验,采用了Fenton 絮凝联合工艺去除废水中的COD(化学需氧量)和浊度,考察了初始pH值、H2O2投加量、H2O2与Fe2+投加物质的量比、反应时间、絮凝剂投加量以及絮凝剂投加时的pH值对COD以及浊度去除效果的影响。结果表明,采用最佳工艺参数组合后,浊度去除率和COD的去除率分别为99.32%和97.27%。  相似文献   
80.
Wang  TianTian  Xu  JiaHuan  Su  XiaoHong  Li  ChenShi  Chi  Yang 《Multimedia Tools and Applications》2019,78(21):29881-29898
Multimedia Tools and Applications - It takes a lot of time and effort to manually locate and fix software bugs. This paper proposes a method for automatically debugging operator related bugs....  相似文献   
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