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61.
A pressure transmitter pipe in a PVC plant failed during shutdown. An investigation was performed in order to determine the failure mechanism. Investigation methods included visual examination, optical and scanning electron microscope analysis, chemical analysis of the material, and microhardness test. It was concluded that the pipe cracking is attributed to chloride SCC.  相似文献   
62.
Due to their unique properties, zinc oxide nanoparticles (ZnO NPs) are invested in many industries, commercial products, and nanomedicine with potential risk for human health and the environment. The present study aims to focus on alterations that might be induced by ZnO NPs in the nephron ultrastructure. Male Wister Albino rats were subjected to ZnO NPs at a daily dose of 2 mg/kg for 21 days. Kidney biopsies were processed to transmission electron microscopy (TEM) and ultrastructural pathology examinations. Exposure to ZnO NPs‐induced ultrastructural alterations in the proximal convoluted tubules (PCTs) and to lesser extent in the distal ones (DCTs), while the loops of Henle were almost not affected. The glomeruli demonstrated dilatation, partial mesangial cells loss, matrix ballooning, slits filtration widening, and basement membrane thickening. Moreover, PCT revealed cytoplasmic necrosis, vacuolation, erosion, and disorganisation of the apical microvilli together with mitochondrial swelling and cristae destruction. The nuclei of the renal cells exhibited nuclear deformity, heterochromatin accumulation, and apoptotic activities. The findings indicate that ZnO nanomaterial have the potential to affect the nephron ultrastructure suggesting alteration in the kidney functions. More work is needed for better understanding the toxicity and pathogenesis of ZnO oxide nanomaterial.Inspec keywords: electron microscopy, zinc compounds, transmission electron microscopy, nanomedicine, biochemistry, diseases, cellular biophysics, biomembranes, kidney, nanofabrication, molecular biophysics, nanoparticles, II‐VI semiconductors, biomedical optical imagingOther keywords: electron microscopic study, unique properties, zinc oxide nanoparticles, ZnO NPs, nephron ultrastructure, Male Wister Albino rats, ultrastructural pathology examinations, NPs‐induced ultrastructural alterations, partial mesangial cells loss, ZnO nonmaterial, ZnO oxide nonmaterial, nephron ultrastructural alterations, kidney biopsies, time 21.0 d, ZnO  相似文献   
63.
The influences of different amount (0.4, 0.7, and 1 wt.%) of Mn addition on the structure, mechanical properties, and corrosion behavior of Cu-Al-Ni shape memory alloys have been studied using differential scanning calorimetry, field emission scanning electron microscopy, transmission electron microscopy, x-ray diffraction, tensile test, shape memory effect test, hardness test, and electrochemical test. It was observed that the transformation temperatures, microstructural characteristics, and mechanical properties are highly sensitive to the composition variations. The obtained results show that the transformation temperatures and mechanical properties of Cu-Al-Ni SMAs exhibited the best results with 0.7 wt.% of Mn addition. These kinds of enhancements are mainly due to the type, amount, and morphology of the martensite phase, including the grain refinement. The result of electrochemical test showed that an increment in Mn content up to 0.7 wt.% improved the corrosion resistance of Cu-Al-Ni SMA. However, further increase of Mn content decreases the corrosion resistance of the alloy.  相似文献   
64.
The anonymity of the darknet makes it attractive to secure communication lines from censorship. The analysis, monitoring, and categorization of Internet network traffic are essential for detecting darknet traffic that can generate a comprehensive characterization of dangerous users and assist in tracing malicious activities and reducing cybercrime. Furthermore, classifying darknet traffic is essential for real-time applications such as the timely monitoring of malware before attacks occur. This paper presents a two-stage deep network chain for detecting and classifying darknet traffic. In the first stage, anonymized darknet traffic, including VPN and Tor traffic related to hidden services provided by darknets, is detected. In the second stage, traffic related to VPNs and Tor services is classified based on their respective applications. The methodology of this paper was verified on a benchmark dataset containing VPN and Tor traffic. It achieved an accuracy of 96.8% and 94.4% in the detection and classification stages, respectively. Optimization and parameter tuning were performed in both stages to achieve more accurate results, enabling practitioners to combat alleged malicious activities and further detect such activities after outbreaks. In the classification stage, it was observed that the misclassifications were due to the audio and video streaming commonly used in shared real-time protocols. However, in cases where it is desired to distinguish between such activities accurately, the presented deep chain classifier can accommodate additional classifiers. Furthermore, additional classifiers could be added to the chain to categorize specific activities of interest further.  相似文献   
65.
Entrepreneurship research lacks empirical evidence about interactions between entrepreneurial team members . This paper examines the role of trust ( cognitive and affective ) and conflict ( task and relationship ) on team performance ( effectiveness and efficiency ) of innovative entrepreneurial teams . Data originated from 88 incubator‐based entrepreneurial teams in Austria . Results indicate that cognitive trust is the cornerstone of innovative entrepreneurial team performance . To maximize efficiency , such teams would rely on high cognitive trust and low task conflict . Nonetheless , the guidelines for being effective centre around high cognitive trust coupled with low task and relationship conflict .  相似文献   
66.
Wireless Networks - Mobile operators aim to enhance the Quality of Service (QoS) in each new mobile network generation. The upcoming 5G mobile network is expected to make a revolutionary...  相似文献   
67.
Tabish  Rohan  Mancuso  Renato  Wasly  Saud  Pellizzoni  Rodolfo  Caccamo  Marco 《Real-Time Systems》2019,55(4):850-888
Real-Time Systems - Multi-core processors have replaced single-core systems in almost every segment of the industry. Unfortunately, their increased complexity often causes a loss of temporal...  相似文献   
68.
Nanocomposite material ZnAl2O4/ZnO was prepared via layered double hydroxides co-precipitation method in the presence of triblock copolymer, Pluronic F127 as the template with different concentrations at pH 7. The material was characterized by XRD, N2 adsorption/desorption, UV–Vis diffused reflectance, TGA–DTA and SEM. XRD and SEM results reveal that ZnAl2O4/ZnO was highly ordered nanocrystalline material. N2 adsorption/desorption studies indicate that the pore size and pore volume increased significantly with the increase in concentration of F127 copolymer template, while the surface area is slightly decreased with increase of F127 template. TGA–DTA results reveal that the thermal stability of material increased after adding F127 template. The material was tested for its photocatalytic activity for a solution containing methyl orange dye and the 95.6% decolorization was achieved within 1 h. The intensive absorption light observed by UV–Vis reflectance of the catalyst confirmed high activity of the catalyst and suggest the probable photocatalytic degradation mechanism.  相似文献   
69.
70.
Lynch syndrome (LS) is the most common cause of inherited endometrial cancer (EC). The prevalence and molecular characteristic of LS in Middle Eastern women with EC have been underexplored. To evaluate the frequency of LS in a cohort of EC patients from Saudi Arabia, a total of 436 EC cases were screened utilizing immunohistochemistry (IHC), MLH1 promoter methylation analysis and next-generation sequencing technology. A total of 53 of 436 (12.2%) ECs were classified as DNA mismatch repair-deficient (dMMR). MLH1 promoter hypermethylation was detected in 30 ECs (6.9%). Three ECs (0.7%) were found to be LS harboring germline pathogenic variants (PVs)/likely pathogenic variants (LPVs): two in the MSH2 gene and one in the MSH6 gene. Three ECs (0.7%) were Lynch-like syndrome (LLS) carrying double somatic MSH2 PVs/LPVs. Seven cases were found to have variants of uncertain significance in cancer-related genes other than MMR genes. Our results indicate that LS prevalence is low among Saudi EC patients and LLS is as common as LS in this ethnicity. Our findings could help in better understanding of the prevalence and mutational spectrum of this syndrome in Saudi Arabia, which may help in defining best strategies for LS identification, prevention and genetic counseling for EC patients.  相似文献   
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