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281.
Auger Depth Profiling of Carbonized SiC/Si Samples 总被引:1,自引:0,他引:1
Silicon carbide (SiC) has been prepared by passing natural gas over (100) oriented hot Si substrate at different temperatures in the range 930~1000℃. Reaction times of 60 and 90 min are used.Depth profile, using Auger Electron Spectroscopy, shows the formation of SiC under a thin coating of carbon for the samples prepared at 930 and 950℃. Annealing, at 1050℃ for 12 h,results in a more pronounced formation of SiC. It is found that at the temperature of 1000℃and reaction times of 60 and 90 min, a hard diamond-like coating is formed. 相似文献
282.
Muhammad Adnan Khan Mubashar Habib Shazia Saqib Tahir Alyas Khalid Masood Khan Mohammed A. Al Ghamdi Sultan H. Almotiri 《计算机、材料和连续体(英文)》2021,66(1):691-706
The innovation and development in data science have an impact in all
trades of life. The commercialization of sport has encouraged players, coaches,
and other concerns to use technology to be in better position than r their opponents. In the past, the focus was on improved training techniques for better physical performance. These days, sports analytics identify the patterns in the
performance and highlight strengths and weaknesses of potential players. Sports
analytics not only predict the performance of players in the near future but it also
performs predictive modeling for a particular behavior of a player in the past. The
impact of a smart player on the success of a team is always a big question mark
before the start of a match. The fans always want to know performance analysis of
these superstar players and they always are interested to get to know more about
their favorite player and they always have high hopes from their favorite player.
Machine learning (ML) based techniques help in predicting the performance of an
individual player as well as for the whole team. The statistics are very vital and
useful for management, fans, and expert analysis. In our proposed framework,
the adaptive back propagation neural network (ABPNN) model is used for the
prediction of a player’s performance. The data is collected from football websites,
and the results are stored in the cloud for fast fetching of data. They can be
retrieved anywhere in the world through cloud storage. The results are computed
with 94% accuracy and the performance of the smart player is formulated for the
success of a team. 相似文献
283.
Girgis Obaid Kimberley Samkoe Kenneth Tichauer Shazia Bano Yeonjae Park Zachary Silber Sassan Hodge Susan Callaghan Mina Guirguis Srivalleesha Mallidi Brian Pogue Tayyaba Hasan 《Nano Research》2021,14(5):1344-1354
The significance and ability for receptor targeted nanoliposomes(tNLs)to bind to their molecular targets in solid tumors in vivo has been questioned,particularly as the efficiency of their tumor accumulation and selectivity is not always predictive of their efficacy or molecular specificity.This study presents,for the first time,in situ near-infrared(NIR)molecular imaging-based quantitation of the in vivo specificity of tNLs for their target receptors,as opposed to tumor selectivity,which includes influences of enhanced tumor permeability and retention.Results show that neither tumor delivery nor selectivity(tumor-to-normal ratio)of cetuximab and IRDye conjugated tNLs correlate with epidermal growth factor receptor(EGFR)expression in U251,U87,and 9L tumors,and in fact underrepresent their imaging-derived molecular specificity by up to 94.2%.Conversely,their in vivo specificity,which we quantify as the concentration of tNL-reported tumor EGFR provided by NIR molecular imaging,correlates positively with EGFR expression levels in vitro and ex vivo(Pearson’s r=0.92 and 0.96,respectively).This study provides a unique opportunity to address the problematic disconnect between tNL synthesis and in vivo specificity.The findings encourage their continued adoption as platforms for precision medicine,and facilitates intelligent synthesis and patient customization in order to improve safety profiles and therapeutic outcomes. 相似文献
284.
Chemical composition and antioxidant activity of seeds of different cultivars of mungbean 总被引:1,自引:0,他引:1
ABSTRACT: Seeds of 4 cultivars (M-1, M-6, NM-92, and NM-98) of mungbean [ Vigna radiata (L.) Wilczek] were investigated for proximate composition, antioxidant potential, fatty acids, tocopherols, and minerals profiles. Hexane-extracted seed oil content of the investigated cultivars of mungbeans ranged from 1.20% to 1.56%. Mungbean seeds were found to be a rich source of protein (20.97% to 31.32%). The contents of Fe, Cu, Mg, Na, K, Ca, and Zn were found to be 105.8 to 190.9, 4.8 to 6.3, 48.6 to 51.7, 382.6 to 562.7, 11.6 to 18.8, 359.2 to 482.9, and 24.9 to 47.2 mg/kg, respectively. The mungbean seeds contained linoleic acid in the highest amount, 340.5 to 465.7 mg/100 g of dry seed, followed by palmitic, oleic, linolenic, stearic, and arachidic acids: 278.1 to 401.2, 212.6 to 293.5, 188.7 to 236.8, 135.5 to 168.4, and 22.8 to 24.5 mg/100 g of dry seed, respectively. The seeds were found to be a rich source of tocopherols (α, γ, δ) ranged from 1.1 to 10.1, 60.7 to 80.9, and 4.6 to 11.2 mg/kg, respectively. Methanolic extracts of the seeds of the mungbean cultivars exhibited a good antioxidant activity as determined in terms of measurement of total phenolic contents (TPC) (0.62 to 1.08 g/100 g of dry matter), percent inhibition of peroxidation (49.8% to 89.2%), reducing power (1.19% to 1.45%), and bleaching β-carotene. The results of the present analytical study revealed these 4 mungbean cultivars to be a potential source of essential fatty acids, antioxidants, minerals and protein, all of which are linked with positive health benefits. 相似文献
285.
In vitro antioxidant and anti-inflammatory activities of fluidized bed ethanol extracts of Pleurotus ostreatus PQMZ91109, PBS281009, M2191 (obtained from a laboratory greenhouse), Agaricus bisporus, Marasmius oreades, Craterellus cornucopioides, and Tuber melanosporum were investigated using free radical scavenging activities, metal chelating effects, inhibition of lipid peroxidation (inhibition of peroxyl radicals), xanthine oxidase, and lipoxygenase, and identification of antioxidant compounds. Levels of different compounds with antioxidant properties demonstrated the presence of more tocopherols than polyphenol carboxylic acids and flavones. HPLC showed that T. melanosporum extracts had high correlation values between levels of different active compounds and antioxidant assay results. Tocopherol levels were highly correlated (R 2=0.867) with anti-inflammatory activities and inhibition of lipid peroxidation. Fluidized bed ethanol extracts from dried mushroom fruit bodies can be a source of products rich in tocopherols, and can constitute an important ingredient in food supplements. 相似文献
286.
287.
Umm-i-Kalsoom Nisar Ali Shazia Bashir Samina Akbar Muhammad Shahid Rafique Ali Mohammad Alshehri Narjis Begum Tanveer Iqbal Aneela Anwar 《International journal of molecular sciences》2022,23(21)
In the present study KrF Excimer laser has been employed to irradiate the Cadmium (Cd) targets for various number of laser pulses of 500, 1000, 1500 and 2000, at constant fluence of 3.6 J cm−2. Scanning Electron Microscopy (SEM) analysis was utilized to reveal the formation of laser induced nano/micro structures on the irradiated target (Cd) surfaces. SEM results show the generation of cavities, cracks, micro/nano wires/rods, wrinkles along with re-deposited particles during irradiation in air, whereas subsurface boiling, pores, cavities and Laser Induced Periodic Surface Structures (LIPSS) on the inner walls of cavities are revealed at the central ablated area after irradiation in propanol. The ablated volume and depth of ablated region on irradiated Cd targets are evaluated for various number of pulses and is higher in air as compared to propanol ambient. Fast Fourier Transform Infrared spectroscopy (FTIR), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD) analyses show the presence of oxides and hydro-oxides of Cd after irradiation in propanol, whereas the existence of oxides is observed after irradiation in air ambient. Nano-hardness tester was used to investigate mechanical modifications of ablated Cd. It reveals an increase in hardness after irradiation which is more pronounced in propanol as compared to air. 相似文献
288.
The success of crowdsourcing (CS) systems depends on sustained participation, which is an ongoing challenge for the majority of CS providers. Unfortunately, participants are frequently demotivated by technical difficulties and the incorrect use of CS systems, which can result in CS failure. Although the literature generally assumes that sustained participation in CS is determined by a shift between intrinsic and extrinsic motivation, the role of system-use practices in facilitating such a shift remains unknown. We explore how CS system-use practices influence participants' sustained motivation, evolving from initiation to progression to sustention. Using the notion of technology-in-practice as a lens, we develop and examine a process model using an in-depth case study of a large-scale ongoing CS project, the Australian Newspaper Digitisation Program. The findings suggest that CS participants' motivation is shaped by an evolving combination of three basic components (i.e., contextual condition, outcome and action intensity) and mediated by two types of system-use practice (i.e., passive and active). Passive-use practices facilitate sustaining motivation from initiation to progression, whereas active-use practices have a key role in sustention. Our study contributes to the emerging literature on the substantial role of system-use practices in sustaining motivation, resulting in sustained participation. The findings also offer actionable insights into improving the viability of CS systems in retaining and motivating continuous and increased contributions from participants. 相似文献
289.
This study deals with the investigation of Nd:YAG laser-assisted ablation and plasma formation of Ti at irradiance of 0.85 GW cm-2 under Ar and Ne environment at various pressures ranging from 10-120 Torr.Laser-induced breakdown spectroscopy is used to evaluate plasma parameters,whereas quartz crystal microbalance is used for ablation yield measurements.The crater depth is evaluated by optical microscopy.The surface features are explored by scanning electron microscope(SEM) analysis a... 相似文献
290.
Silicon - This work presents the design and simulation of a novel double-gate L-shaped Schottky barrier MOSFET (DG-LS-SB-MOSFET). The device uses a low work function metal near source-channel... 相似文献