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991.
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
992.
993.
Scientometrics - This research letter discusses whether Arab Spring explains the changes in research productivity and impact of Arab countries by identifying non-sociopolitical factors that can be... 相似文献
994.
Recently, many researchers have focused on their studies on the analysis of nanofluid flows due to their participation in the enhancement of heat transfer rates in industrial processes. The ordinary fluids, such as water, mineral oils, and so on, are known for their low thermal conductivity in heat transfer processes. A significant enhancement in the thermal properties of ordinary fluid may be obtained by adding nanoparticles having a diameter of less than 100 nm or suspension of fibers. Better spreading, wetting, dispersion, and stability and with acceptable viscosity are the main advantageous properties of nanofluids on a solid surface. The nanofluids are encountered in various thermal engineering systems such as in heat exchangers, refrigeration, thermal management of fuel cells, cooling of nuclear reactors, microelectromechanical systems, and others. In particular, the thermal conversion is known as a great application of nanotechnology, and many studies have been achieved with such fluids in heat exchangers. Therefore, this paper aims to present a global insight into the different applications of nanofluids in various heat exchangers, that is, heat pipe and plate-fin heat exchangers. All research works have been summarized into three main parts: laminar, transition, and turbulent nanofluid flow regimes. 相似文献
995.
UNStudio Ben van Berkel Hannes Pfau Astrid Piber Jin Xing Hufton+Crow Seth Powers 《中国建筑装饰装修》2018,(4)
正UNStudio由Ben van Berkel和Caroline Bos创立,是一个国际性的建筑设计网络。拥有三个全方位服务的国际事务所,分别位于阿姆斯特丹、香港和上海。专于建筑、室内建筑、产品设计、城市发展和基础设施项目。地址:浙江省杭州市钱江新城富春路业主方:凯德集团建筑面积:392526m~2项目年份:2017醒目的裙楼之上坐落着两座流线型的高楼,从中可以饱览钱塘江和西湖的迷人风光。 相似文献
996.
Metidji Nadia Bacha Nacer Eddine Younes Abderrahmane Saidi Djaffar 《Powder Metallurgy and Metal Ceramics》2020,59(3-4):160-170
Powder Metallurgy and Metal Ceramics - Recent research on nanocrystalline FeAl alloys has shown that these alloys are of high importance due to their promising structural and mechanical properties,... 相似文献
997.
Mariame Amine Abdellatif Kobbane Jalel Ben‐Othman Abdellaziz Walid 《International Journal of Communication Systems》2020,33(8)
Recently, academic and industrial research communities are paying more explicit attention to the 5G multiple radio access technology ultra‐dense networks (5G multi‐RAT UDNs) for boosting network capacity, especially in UD urban zones. To this aim, in this paper, we intend to tackle the user association problem in 5G multi‐RAT UDNs. By considering the decoupled uplink/downlink access (DUDA), we divide our user association problem into two distinct subproblems representing, respectively, the uplink and the downlink channels. Next, we formulated each one as a nonlinear optimization problem with binary variables. Then, to solve them, we were restricted by the hard complexity, as well as the hard feasibility of centralized user association schemes. Thus, to resolve our user association problem in a reasonable time and distributed manner, we formulated each subproblem as a many‐to‐one matching game based on matching theory. Next, we provide two fully distributed association algorithms to compute the uplink and downlink stable matching among user equipments (UEs) and base stations (BSs). Simulation results corroborate our theoretical model and show the effectiveness and improvement of our achieved results in terms of the overall network performance, quality of service (QoS), and energy efficiency (EE) of UEs. 相似文献
998.
The shape memory effect (SME) does not only concern the macroscopic structure. It concerns also the polymer structure at morphological, macromolecular, and molecular scales. This effect may depend on different physicochemical properties like morphology heterogeneity, chain rigidity, steric hindrance, chain polarity, free volume, cross-linking or entanglement density, molecular shape and weight, and so on. Hence, finding the relationship between the SME and these properties is very important. This can help to obtain the knowledge about the phenomenon origin and mechanism. One of the basic polymer properties, which can have direct SME, may be the molecular weight (Mw ). The question here is: If the Mw of a shape memory polymer (SMP) changes, for different reasons like degradation, what will be the effect of this change on its SME. In order to answer to this question, the investigation is focused on an SMP blend of 40% poly(ɛ-caprolactone) (PCL) and 60% styrene-butadiene-styrene (SBS). Then, enzymatic hydrolysis is performed on this blend to change its Mw . It is shown that this change is only related to the variation in the Mw of PCL. After that, different samples with a distinct average Mw are prepared and characterized by various experimental methods. Shape memory tests are performed on these blends, and the recovery rate (Rr ) for each of them is determined. It is found that when Mw of PCL decreases, its degree of crystallinity, its glass transition, and its melting temperatures, corresponding to the PCL phase, increase. However, the elongation at break of the blend declines with the reduction in Mw . The tests show that the alteration in the blend's Mw influences its SME. Indeed, Rr of the (PCL/SBS) mixture drops with the decrease in Mw of PCL. 相似文献
999.
Zainal Abidin Mohd Yusof Iqbal Ahmed Muhammad Saad Khan S. Altaf Hussain Ahmad Hussain Ibrahim bin Abdul Mutalib Khaled S. Balkhair Muhammad H. Albeirutty 《化学工程与技术》2015,38(12):2170-2180
Thermal properties of fossil fuel are the key fundamental characteristics, which can distinguish any compound as a potential fuel. The performance of diesel fuel blend along with stability and solubility parameter designs are evaluated. The results from the experimental study indicate that the increase in hydrogen peroxide (H2O2) amount enhances the cetane number of diesel fuel blend significantly. However, the calorific value decreases as compared to pure diesel fuel. All values performed well according to the ASTM D‐975 diesel testing method. The thermodynamics of the prepared fuel blends also revealed that substantial solubility and diesel/H2O2 blend stability are provided even at lower temperatures. Such blends can be used as a feasible replacement of pure diesel fuel. 相似文献
1000.
Wafaa E. Rashwan Khaled S. Abou-El-Sherbini Mohammed A. Wahba Sohair A. Sayed Ahmed Peter G. Weidler 《SILICON》2020,12(9):2017-2029
Aluminosilicate (Al-MCM-41) was synthesized via a modified wet-method in a Si/Al atomic ratio of 13.64:1.00 and calcination at 500 °C. The structural 相似文献