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排序方式: 共有506条查询结果,搜索用时 46 毫秒
61.
Ramesa Shafi BHAT Amina El GEZEERY Abir Ben BACHAN Mona Awad ALONAZI Leena Saleh ALSUHAIBANI Afaf El-ANSARY 《Biocell》2019,43(2):65-71
Fluoride is a key ingredient of many psychiatric drugs like fluoxetine (Prozac®, Fluoxetine®). Pregnant women
frequently use this drug as they suffer from depression and anxiety disorders during this period. Fluoxetine is able to
reach the fetus through the placenta and passes to the newborn through milk. In the present study, female Wistar rats
were treated with 5, 10, and 20 mg/L fluoxetine (containing 94% fluorides) from pregnancy day 10 to day 20. After
delivery, the levels of the enzymatic antioxidants in the brain of their offspring at postnatal day 2 were measured. The
results showed that, in all fluoxetine exposed groups compared with the control group, there was a significant decrease
(P < 0.01) in the glutathione, catalase, glutathione S-transferases and potassium and a non- significant increase (P >
0.05) in the activity of malondialdehyde and creatine kinase. The results suggest that fluoxetine may be a developmental
neurotoxicant due to presence of fluoride hence must be used carefully during pregnancy. 相似文献
62.
Dalia Heggo Shinichi Ookawara Teruhisa Ohno Toru Nakai Yoshihisa Matsushita Mona Gamal Eldin Masahiro Ohshima 《加拿大化工杂志》2020,98(1):119-126
Dense photocatalyst slurry was employed for the synthesis of p-anisaldehyde under solar light irradiation. An Fe-modified rutile TiO 2 (Fe-TiO 2, 34.5 m 2/g) photocatalyst was used as a visible-light-responsive photocatalyst. A conventional TiO 2 (P25, 35 m 2/g) photocatalyst was also examined as a reference catalyst. XRD patterns and diffuse reflectance spectra showed that Fe-TiO 2 consists of 100 % rutile phase and absorbs more visible light compared to P25, respectively. The catalyst powder was suspended in an ethyl acetate solution of p-methoxytoluene in the mini-reactor, with oxygen bubbling, under a solar simulator, visible light, and UV LEDs. p-anisaldehyde, as a reaction product, was analyzed by sampling using gas-chromatograph. Regardless of the light source, Fe-TiO 2 always outperformed P25 in terms of both generation rates (GR) of p-anisaldehyde and energy requirements (ER). It was demonstrated that the highly dense Fe-TiO 2 slurry was efficient for the synthesis under solar light owing to the small size of the reactor. The small amount of Pt and ZrO 2 cocatalysts significantly enhanced the GR under solar light. By adopting a visible light responsive Fe-TiO 2 photocatalyst, the mini slurry-bubble reactor under solar light achieved a high GR per catalyst mass (CM), which is one to two orders higher than that reported by most previous studies with high-power lamps. 相似文献
63.
Naiming Liu S. Emad Rezaei Wade Aaron Jensen Shaowei Song Zhifeng Ren Keivan Esfarjani Mona Zebarjadi Jerrold Anthony Floro 《Advanced functional materials》2019,29(38)
A β‐FeSi2–SiGe nanocomposite is synthesized via a react/transform spark plasma sintering technique, in which eutectoid phase transformation, Ge alloying, selective doping, and sintering are completed in a single process, resulting in a greatly reduced process time and thermal budget. Hierarchical structuring of the SiGe secondary phase to achieve coexistence of a percolated network with isolated nanoscale inclusions effectively decouples the thermal and electrical transport. Combined with selective doping that reduces conduction band offsets, the percolation strategy produces overall electron mobilities 30 times higher than those of similar materials produced using typical powder‐processing routes. As a result, a maximum thermoelectric figure of merit ZT of ≈0.7 at 700 °C is achieved in the β‐FeSi2–SiGe nanocomposite. 相似文献
64.
Maximum likelihood estimation of change point from stationary to nonstationary in autoregressive models using dynamic linear model
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Reza Sheikhrabori Majid Aminnayeri Mona Ayoubi 《Quality and Reliability Engineering International》2018,34(1):27-36
Change point estimation is a useful concept in time series models that could be applied in several fields such as financing, quality control. It helps to decrease costs of decision making and production by monitoring stock market and production lines, respectively. In this paper, the maximum likelihood technique is developed to estimate change point at which the stationary AR(1) model changes to a nonstationary process. Filtering and smoothing of dynamic linear model are used to estimate unknown parameters after change point. We also assume that correlation exists between samples' statistics. Simulation results show the effectiveness of the proposed estimators to estimate the change point of stationary. In addition based on Shewhart control chart, filtering has a better accuracy in comparison to smoothing. A real example is provided to illustrate the application. 相似文献
65.
Pattern Analysis and Applications - One subject that has been considered less is a binary classification on data streams with concept drifting in which only information of one class (target class)... 相似文献
66.
Water Resources Management - In this study, a new methodology is presented for conjunctive use of canal and pond to assess the role of ponds in saving local water and optimizing use of them in... 相似文献
67.
Shalaby Mohamed Shokair Mona Messiha Nagy Wadie 《Wireless Personal Communications》2020,114(3):2327-2361
Wireless Personal Communications - In most scenarios of wireless sensor networks (WSNs), different traffic types have specific service requirements. None of the previous MAC schemes has been able... 相似文献
68.
Hassan Mona Bakri Alsharif Sameer Alhumyani Hesham Ali Elmustafa Sayed Mokhtar Rania A. Saeed Rashid A. 《Wireless Personal Communications》2021,116(3):2367-2390
Wireless Personal Communications - Smart Home is one of the most established applications of the Internet of Things. Almost every equipment we use in our daily life—appliances, electric... 相似文献
69.
Nadia A. Mohamed Nahed A. Abd El-Ghany Mona M. Fahmy Perihan A. Khalaf-Alla 《国际聚合物材料杂志》2018,67(2):68-77
Novel polymaleimide containing dibenzoyl hydrazine pendant group, poly[N-benzoyl-4-(N-maleimido)-phenyl hydrazide], and its metal complexes have been synthesized. Their antimicrobial activity against Bacillus subtilis, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Escherichia coli bacteria and that against Aspergillus fumigatus, Syncephalastrum racemosum, Geotrichum candidum, and Candida albicans fungi were investigated. The polymer–metal complexes showed better antimicrobial activity than that of the parent polymer. The inhibition of the growth of the microbes remarkably depends on the type of the metal in the complexes. The polymer–Co(II) and the polymer–Cd(II) complexes are more potent in inhibition of the tested microbes growth than the rest of the prepared complexes. 相似文献
70.
This paper describes the application of ultrasound waves on hydrodynamics and mass transfer characteristics in the gas-liquid flow in a T-shape microreactor with a diameter of 800 μm.A 1.7 MHz piezoelectric transducer (PZT) was employed to induce the vibration in this microreactor.Liquid side volumetric mass transfer coefficients were measured by physical and chemical methods of CO2 absorption into water and NaOH solution.The approach of absorption of CO2 into a 1 mol· L-1 NaOH solution was used for analysis of interfacial areas.With the help of a photography system,the fluid flow patterns inside the microreactor were analyzed.The effects of superficial liquid velocity,initial concentration of NaOH,superficial CO2 gas velocity and length of microreactor on the mass transfer rate were investigated.The comparison between sonicated and plain microreactors (microreactor with and without ultrasound) shows that the ultrasound wave irradiation has a significant effect on kLa and interfacial area at various operational conditions.For the microreactor length of 12 cm,ultrasound waves improved kLa and interfacial area about 21% and 22%,respectively.From this study,it can be concluded that ultrasound wave irradiation in microreactor has a great effect on the mass transfer rate.This study suggests a new enhancement technique to establish high interfacial area and kLa in microreactors. 相似文献