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排序方式: 共有299条查询结果,搜索用时 593 毫秒
91.
92.
Saba Samatya Hidenobu Mizuki Yudai Ito Hidetaka Kawakita Kazuya Uezu 《Reactive and Functional Polymers》2010,70(1):63-68
A novel adsorbent, Zr(IV)-immobilized resin, was prepared by surface template polymerization. This adsorbent, prepared by adding polystyrene (PS) to resin, has a high adsorption capacity for the removal of fluoride ion from aqueous solutions. The adsorption capacity increased with rising PS concentration, since the specific surface area can be effectively increased by adding polystyrene as a porogen. The adsorption isotherm has been modeled by the Langmuir and Freundlich equations. The adsorption isotherms were well described by the Langmuir equation. The removal of fluoride was also carried out using a column method. The presence of PS in the resin exerted a remarkable influence on the uptake of fluoride ion. The fluoride adsorbed on the resin was quantitatively eluted with 0.1 M NaOH. 相似文献
93.
McWhirter Ellen Hawley; Crothers Marciana; Rasheed Saba 《Canadian Metallurgical Quarterly》2000,47(3):330
The authors investigated the influence of a 9-week career education class on career decision-making self-efficacy, vocational skills self-efficacy, perceived educational barriers, outcome expectations, educational plans, and career expectations among a sample of 166 high school sophomores. Using a nonrandomized, within-subjects crossover design, the authors collected pretest, posttest, and follow-up data with a health education class as the control condition. Post- and follow-up testing suggest that the class resulted in increased career decision-making self-efficacy, vocational skills self-efficacy, and short-term gains in outcome expectations but did not influence perceived educational barriers. Participants enrolled in the career education class in the first quarter were more likely to change career plans than were those in the control condition. Implications for practice and future research are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Microscopic brain tumor detection and classification using 3D CNN and feature selection architecture
Amjad Rehman Muhammad Attique Khan Tanzila Saba Zahid Mehmood Usman Tariq Noor Ayesha 《Microscopy research and technique》2021,84(1):133-149
Brain tumor is one of the most dreadful natures of cancer and caused a huge number of deaths among kids and adults from the past few years. According to WHO standard, the 700,000 humans are being with a brain tumor and around 86,000 are diagnosed since 2019. While the total number of deaths due to brain tumors is 16,830 since 2019 and the average survival rate is 35%. Therefore, automated techniques are needed to grade brain tumors precisely from MRI scans. In this work, a new deep learning‐based method is proposed for microscopic brain tumor detection and tumor type classification. A 3D convolutional neural network (CNN) architecture is designed at the first step to extract brain tumor and extracted tumors are passed to a pretrained CNN model for feature extraction. The extracted features are transferred to the correlation‐based selection method and as the output, the best features are selected. These selected features are validated through feed‐forward neural network for final classification. Three BraTS datasets 2015, 2017, and 2018 are utilized for experiments, validation, and accomplished an accuracy of 98.32, 96.97, and 92.67%, respectively. A comparison with existing techniques shows the proposed design yields comparable accuracy. 相似文献
95.
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This study analyses the role played by dynamic capability and intangible assets of international new ventures from developed
markets at the initial survival and growth stages of internationalization. 相似文献
96.
The electrical conductivity in ZrO2 doped with various molar ratios of TiO2 has been measured at different temperatures. Phase transitions depending on the temperature for different molar compositions
were investigated by doping of the samples. The conductivity is also found to increase with rise in temperature till 200 °C
and thereafter decreases due to collapse of the fluorite framework. A second rise in conductivity in the doped samples around
462 °C is observed due to phase transition of ZrO2. X-ray powder diffraction recorded at high temperature show the effect of doping and the phase relationships of doped materials.
DTA was also carried out for confirming doping effect and phase transition in samples. 相似文献
97.
Mehvish Saleem Saba Zahid Sarah Ghafoor Hina Khalid Haffsah Iqbal Rabia Zeeshan Sarfraz Ahmad Anila Asif Abdul Samad Khan 《应用聚合物科学杂志》2021,138(18):50336
This study aimed to synthesize experimental composites reinforced with various concentrations (0, 40, 50, and 60 wt%) of nano-hydroxyapatite grafted glass fibers. The release of monomers, residual monomers, and in-vitro bioactivity of composite groups were evaluated after 1, 7, and 28 days. Compressive strength/ modulus, cell viability (by direct and indirect method), and bacterial adhesion were evaluated. The results showed that bis-GMA was released from all samples. TEGDMA released from 50 and 60 wt% samples on day 1 and UDMA showed negligible release. Compressive strength values of 40 wt% sample were higher than other experimental groups. New apatite layer was formed, whereby both direct and indirect methods demonstrated cell viability. The numbers of active colonies grown were least for 60 wt% sample while their number increased over time. The nano-hydroxyapatite/glass fibers have potential to be used as filler in dental composites and experimental composites were found to be biocompatible and comparable with commercial material. 相似文献
98.
Estakhri Saba Darabi Elham Akbari-Adergani Behrouz Elahi Seyed Mohammad 《Journal of Porous Materials》2021,28(4):989-1003
Journal of Porous Materials - Staphylococcus aureus is most common causes of hospital-acquired infections and food-associated disease. In the last years, sensing platform based on fluorescence-... 相似文献
99.
Shahzad Maqsood Khan Nafisa Gull Muhammad Azeem Munawar Saba Zia Farheen Anjum Muhammad Sajid Iqbal Muhammad Shafiq Atif Islam Syed Muhammad Awais Muhammad Arif Butt Muhammad Taqi Zahid Butt Tahir Jamil 《Iranian Polymer Journal》2016,25(6):475-485
The present study investigates the thermal, mechanical and microscopic properties of polyphenylene sulphide/carbon fiber (PPS/CF) composites by incremental number of fiber layers. The composites were prepared by hand lay-up technique followed by compression molding. A superior matrix-reinforcement adhesion was attained without the use of coupling agent and mechanical stability of the composites improved with increasing fiber layers. Transverse rupture strength and bending modulus were improved by 59.84 and 125.21 %, respectively, without loss in toughness. Impact strength and hardness values were enhanced while storage modulus, loss modulus and damping factor were dropped by increases in fiber layers. Thermogravimetric analysis (TGA) indicated a gradual rise in thermal stability (16.84 %) of the composite as compared to pure matrix. Surface morphology and crack propagation were studied by optical microscopy. It was found that crack was propagated in a linear plane by applying load. In addition, scanning electron microscopy (SEM) illustrated steady alignment of fibers and uniform distribution of the matrix around reinforcement. Based on the obtained results, fiber layers showed great potential for enhancement of thermal and mechanical properties of the composites. 相似文献
100.
Saba Khan Sanjula Baboota Javed Ali R. S. Narang 《Drug development and industrial pharmacy》2016,42(2):209-220
The present work was aimed at developing an optimized oral nanostructured lipid carrier (NLC) formulation of poorly soluble atorvastatin Ca (AT Ca) and assessing its in vitro release, oral bioavailability and pharmacodynamic activity. In this study, chlorogenic acid, a novel excipient having synergistic cholesterol lowering activity was utilized and explored in NLC formulation development. The drug-loaded NLC formulations were prepared using a high pressure homogenization technique and optimized by the Box-Behnken statistical design using the Design-Expert software. The optimized NLC formulation was composed of oleic acid and stearic acid as lipid phase (0.9% w/v), poloxamer 188 as surfactant (1% w/v) and chlorogenic acid (0.05% w/v). The mean particle size, polydispersity index (PDI) and % drug entrapment efficiency of optimized NLC were 203.56?±?8.57?nm, 0.27?±?0.028 and 83.66?±?5.69, respectively. In vitro release studies showed that the release of drug from optimized NLC formulations were markedly enhanced as compared to solid lipid nanoparticles (SLN) and drug suspension. The plasma concentration time profile of AT Ca in rats showed 3.08- and 4.89-fold increase in relative bioavailability of developed NLC with respect to marketed preparation (ATORVA® tablet) and drug suspension, respectively. Pharmacodynamic study suggested highly significant (**p?0.01) reduction in the cholesterol and triglyceride values by NLC in comparison with ATORVA® tablet. Therefore, the results of in vivo studies demonstrated promising prospects for successful oral delivery of AT Ca by means of its chlorogenic acid integrated NLC. 相似文献
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