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Saraei Sina Hassanzadeh Khalilarya Shahram 《Journal of Mechanical Science and Technology》2018,32(4):1889-1896
Journal of Mechanical Science and Technology - Split injection strategies are attractive combustion strategies due to their potential in satisfying strict emission standards. In this study, a... 相似文献
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Ivonne A. Montes-Mojarro Saki Hassas Sina Staehle Philip Sander Niklas Harland Lina Maria Serna-Higuita Irina Bonzheim Hans Bsmüller Arnulf Stenzl Falko Fend 《International journal of molecular sciences》2022,23(15)
Diagnosis and grading of non-invasive papillary urothelial tumors according to the current WHO classification poses some challenges for pathologists. The diagnostic reproducibility of separating low-grade and high-grade lesions is low, which impacts their clinical management. Whereas papillary urothelial neoplasms with low malignant potential (PUN-LMP) and low-grade papillary non-invasive carcinoma (LG-PUC) are comparable and show frequent local recurrence but rarely metastasize, high-grade papillary non-invasive carcinoma (HG-PUC) has a poor prognosis. The main objective of this work is to develop a multiparametric classification to unambiguously distinguish low-grade and high-grade tumors, considering immunohistochemical stains for p53, FGFR3, CK20, MIB-1, p16, p21 and p-HH3, and pathogenic mutations in TP53, FGFR3, TP53, ERCC2, PIK3CA, PTEN and STAG2. We reviewed and analyzed the clinical and histological data of 45 patients with a consensus diagnosis of PUN-LMP (n = 8), non-invasive LG-PUC (n = 23), and HG-PUC (n = 14). The proliferation index and mitotic count assessed with MIB-1 and P-HH3 staining, respectively correlated with grading and clinical behavior. Targeted sequencing confirmed frequent FGFR3 mutations in non-invasive papillary tumors and identified mutations in TP53 as high-risk. Cluster analysis of the different immunohistochemical and molecular parameters allowed a clear separation in two different clusters: cluster 1 corresponding to PUN-LMP and LG-PUC (low MIB-1 and mitotic count/FGFR3 and STAG2 mutations) and cluster 2, HG-PUC (high MIB-1 and mitosis count/CK20 +++ expression, FGFR3 WT and TP53 mutation). Further analysis is required to validate and analyze the reproducibility of these clusters and their biological and clinical implication. 相似文献
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Improving electrical conductivity of poly methyl methacrylate by utilization of carbon nanotube and CO2 laser 下载免费PDF全文
Ayub Karimzad Ghavidel Taher Azdast Mohammadreza Shabgard Amir Navidfar Sina Sadighikia 《应用聚合物科学杂志》2015,132(42)
In this work, the electrical surface conductivity enhancement of injection‐molded multiwalled carbon nanotube (MWCNT)/poly(methyl methacrylate) (PMMA) nanocomposite by using CO2 laser processing was studied. Variable input factors are considered as MWCNT concentration (in three levels 0.5, 1, and 1.5 wt %), the laser feed angle with the flow direction (in five levels 0°, 30°, 45°, 75°, and 90°), and the cavity machining method that were produced by electrodischarge machining and computer numerical control milling with finishing process. The studies show that the irradiation of laser and utilization of covering gas could enhance the CNT–CNT contacts and the surface electrical conductivity. The morphology of laser‐irradiated surface by using scanning electron microscope certified that the conductive network generated from CNT–CNT contacts can transfer the electrical current. The findings clearly show that the laser feed angle with the flow direction influenced the electrical conductivity. The maximum conductivity (~ 5.310 × 10?4 S) was observed at 75°. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42671. 相似文献
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Sina Saremi-Yarahmadi Bala Vaidhyanathan K.G. Upul Wijayantha 《International Journal of Hydrogen Energy》2010
It is demonstrated for the first time that significant enhancement of photoelectrochemical performance could be achieved by using microwave-assisted annealing for the fabrication of α-Fe2O3 thin films. The process can also lead to significant energy savings (>60% when compared with conventional methods). Different types of Fe thin films were oxidized using both microwave and conventional heating techniques. The photoelectrochemical performance of electrodeposited, undoped and Si-doped iron oxide samples showed that microwave-annealing resulted in superior structural and performance enhancements. The photocurrent densities obtained from microwave annealed samples are among the highest values reported for α-Fe2O3 photoelectrodes fabricated at low temperatures and short times; the highest photocurrent density at 0.55 V vs. VAg/AgCl, before the dark current onset, was 450 μA cm−2 for the Si-doped films annealed at 270 °C for 15 min using microwave irradiation (and 180 μA cm−2 at 0.23 V vs. VAg/AgCl) while conventional annealing at the same temperature resulted in samples with negligible (3 μA cm−2) photoactivity. In contrast, a 450 °C/15 min conventional heat treatment only resulted in a film with 25% lower photocurrent density than that of the microwave annealed sample. The improved performance is attributed to the lower processing temperatures and rapidity of the microwave method that help to retain the nanostructure of the thin films whilst restricting the grain growth to a minimum. The lower processing temperature requirements of the microwave process can also open up the possibility of fabricating hematite thin films on conducting, flexible, plastic electronic substrates. 相似文献
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