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41.
Advanced glycation endproducts stimulate the MAP-kinase pathway in tubulus cell line LLC-PK1 总被引：1，自引：0，他引：1
A Simm G Münch F Seif O Schenk A Heidland H Richter S Vamvakas R Schinzel 《Canadian Metallurgical Quarterly》1997,410(2-3):481-484
Advanced glycation endproducts (AGEs) are suggested to play an important role in diabetic nephropathy. They induce specific cellular responses such as the release of cytokines in different cell lines. The effect of AGEs on signal transduction pathways was investigated in the renal tubulus cell line LLC-PK1. Using a serine-phosphate-specific antibody AGE-induced cellular responses associated with phosphorylation/dephosphorylation events were demonstrated. In particular, the p42MAP kinase and its downstream target, the AP-1 complex, are shown to be activated by AGE-BSA but not by BSA. In contrast, only partial phosphorylation is observed for the p70S6-kinase. Thus, AGEs appear to induce specific signal transduction pathways. 相似文献
42.
Ali Asghar Zomorodkia Davood Zaarei Mehdi Ardjmand Mohsen Gorji Saeed Bazgir 《新型炭材料》2020,(6):739-751
以氧化石墨烯(GO)、聚氨酯(PU)和亲水性聚2-丙烯酰胺-2 -甲基丙烷磺酸(PAMPS)为原料,制备出无支撑的PU基复合膜和PAMPS基复合膜.研究氧化石墨烯聚合物基膜用于含极性材料废液如水、氨水、以及含非极性二氯甲烷和氨-二氯甲烷混合废液的渗透行为.采用不同表征方法如X射线衍射仪(XRD)、接触角、场发射扫描电子... 相似文献
43.
Seyed Ataollah Ashrafzadeh Ali Asghar Ghadimi Ali Jabbari Mohammad Reza Miveh 《风能》2024,27(3):258-276
Air-cored axial-flux permanent-magnet synchronous generators (AFPMSGs) are potential candidates for gearless direct-coupled wind turbines (DCWTs) owing to providing high efficiency and power density. The design of a DCWT generator is so complicated since the generator cost, dimension, and weight affected by gear elimination. Therefore, it is essential to find an optimal AFPMSG design at rated conditions. In this paper, an accurate procedure for the optimal design of an air-cored AFPMSG applicable for DCWTs is proposed. The genetic algorithm (GA) is used for multi-objective design optimization to reach the optimal configuration as well as system dimension in order to decrease the weight, increase the power density and enhance the effectiveness of the generator. To validate the efficiency of the suggested optimization proceducer, a 30 kW AFPMSG has been considered as a case study. The results of optimization have been investigated by finite element analysis (FEA). A prototype generator is also fabricated, and the test results are offered and compared with the numerical study. The outcomes show that there exists an acceptable agreement between FEA and experimental outcomes with the error percentage about of 1.35%. 相似文献
44.
Hafza Asghar;Tabinda Riaz;Hafiz Abdul Mannan; 《应用聚合物科学杂志》2024,141(44):e56191
Developed specifically to address leakage and stability concerns inherent in liquid electrolytes, this study presents a significant advancement in polymer gel electrolyte (PGE) formulation by combining potassium iodide (KI), ammonium iodide (AI) salts, and polyvinylidene fluoride-co-hexafluoropropylene (PVDF-co-HFP) as a host polymer. The tape casting method was employed to deposit the standard TiO2 paste as the photoanode and platinum paste as the counter electrode. N3 dye was incorporated, and PVDF-co-HFP was used as the PGE between the electrodes. The conductivity of PGE was measured by using a digitized conductivity meter. The quasi solid-state solar cell (QS-DSSC) assembled using single salts (KI, and AI), and mixed cations PGE was examined via photocurrent–voltage characteristics, and electrochemical impedance spectroscopy. The augmented ionic conductivity directly influences the efficiency of DSSCs. Notably, incorporating a mixed salt (KI + AI) within the PGE enhances ionic conductivity compared to single-salt-based counterparts. The resultant DSSCs using mixed salt PGE exhibit a Voc of 600 mV, Jsc of 1.01 mA/cm2, FF of 0.6089, and an efficiency of 0.369%, outperforming those using KI or AI. This highlights the perceptible advantages of employing this innovative electrolyte composition to enhance solar cell performance. 相似文献
45.
Piotr Piatkowski Asghar Ali Hussain Alawadhi Ali S. Alnaser 《Advanced Engineering Materials》2023,25(6):2201361
46.
Mohsen Rezaeimanesh S. Ali Asghar Ghoreyshi Seyed Mohsen Peyghambarzadeh Seyed Hassan Hashemabadi 《加拿大化工杂志》2023,101(7):3856-3873
Mathematical modelling of the thickness of the coke layer growing over months in millisecond cracking reactors is a dilemma in computational fluid dynamics (CFD) simulation. To address the time scale issue, a quasi-steady state (QSS) approach was employed through a comprehensive coupled reactor/firebox CFD model in the current study. The model was applied to predict the time-dependent behaviour of coke deposition and to determine the appropriate operating conditions for maximum olefin yields over an industrial furnace run length. A novel algorithm was designed to overcome the complexity of QSS simulation of the CFD model, which is a combination of reactive turbulence flow, combustion, and radiation models. The furnace parameters were studied as a function of two variables: the dilution steam-to-feed ratio and the liberated heat by the burners. The results indicated that the run length can be extended by up to 20% while retaining the main product yields. This study offers practical suggestions to maximize the run length in the operation. 相似文献
47.
The present article elaborates the Graetz problem for the Robertson-Stiff fluid model with imposed iso-thermal conditions. The closed-form expression of Robertson-Stiff fluid velocity is obtained. Employing the classical separation of variables approach, the energy equation of the said problem is reduced into an eigenvalue problem. The solution of the eigenvalue problem is developed numerically via the MATLAB built-in algorithm BVP4C. The constants appearing in series solutions are computed by Simpson's rule. The special case of this analysis with appropriate scaling is also applicable for the Bingham, power-law, and Newtonian fluid models. The impact of the dissipation function on Nusselt numbers and mean temperature is also considered. The pictorial representation of average temp7erature and Nusselt number are discussed in the presence of the plug radius, power-law index, and Brinkman number. It is observed that the presence of the plug radius and power-law index delay the prevalence of fully developed conditions for the Nusselt number. Moreover, the local Nusselt number for channel confinement attains higher values as compared with tube confinement. The present investigation has numerous applications in the field of engineering, nanotechnology, biomedical sciences, and development of several thermal types of equipment or microfluidic devices. 相似文献
48.
Hadi Ahmadi Ehsan Hosseini Withita Cha-Umpong Mojtaba Abdollahzadeh Asghar Habibnejad Korayem Amir Razmjou Vicki Chen Mohsen Asadnia 《Advanced Materials Technologies》2021,6(10):2000665
Lithium consumption is estimated to face a considerable rise in the next decade; thus, finding new reproducible lithium resources such as brine deposits and seawater has become a fast-growing research topic. However, Li+ extraction from these resources is challenging due to its low concentration and presence of other monovalent cations exhibiting identical chemical properties. Here, it is discovered that tannic acid (TA) inside graphene oxide (GO) nanochannel acts as natural ion trapper, which possesses lithiophilic elements. The lithium-rich feed is achieved by using the potential-driven TA-GO membrane by excluding lithium ions from other monovalent cations. The results showed that the ion trapping capability of inexpensive TA-GO membrane is Li+ > Na+ > K+ with Li trapping energy of − 593 KJ mol−1, respectively, where its trapping efficiency goes into a top rank among their expensive synthetic counterparts. Evaluating the combined effect of three key parameters, including barrier energy, hydration energy, and binding energy illustrates that required energy to transport Li-ion through the membrane is higher than that for other monovalent. This proof-of-concept work opens up an avenue of research for designing a new class of ion-selective membranes, based on the incorporation of naturally low cost available lithiophilic guest molecules into 2D membranes. 相似文献
49.
Mohammad Zakertabrizi Ehsan Hosseini Asghar Habibnejad Korayem Amir Razmjou 《Advanced Materials Technologies》2021,6(10):2001049
Balancing ionic selectivity against permeability in filters made from graphene remains a challenge today. Interlayer distance, as the most important factor, dominates nearly all aspects of the flow inside the channel, from the formation of water molecules to the hydration shell of the ions. Unraveling the effects of the interlayer distance on the proton diffusion process helps lay a foundation for the cutting-edge proton conduction technology. Here, the reactive molecular dynamics simulations are used to probe the proton flow through a series of hydrated graphene channels with different interlayer distance values. The results show that the proton-selectivity experiences a sharp increase when the channel height is reduced to values under 8 Å, which is near the end of the hydration radii range of the monovalent and divalent cations. Reducing the interlayer distance also decreases the number of confined water molecules, consequently reducing the proton diffusion rate as the hopping platform fades. This way, spatial hindrance combined with the proton-selective Grotthuss mechanism provide a proton-exclusive membrane. The outputs of this work can be used for the optimization of proton-exclusive nanochannels and to serve affordable proton-exchange membranes (PEMs) for technological advancement in diverse fields from PEM fuel cells to storing liquid hydrogen. 相似文献
50.
The yarn pullout test is a prevailing and particular method to evaluate the effects of yarn properties and the structural characteristics of the fabric on the fabric mechanical performance. In this research, a theoretical model of yarn pull out is presented to determine the reserved energy of weft-knitted fabrics with rib 1 × 1 structure. This model is based on the fabric dimensional properties, i.e. stitch length, wale density, yarn diameter and contact angle of yarns. In order to appraise the proposed model, five different double jersey weft-knitted fabrics with rib 1 × 1 structure were produced and exposed to pullout test. Comparison between deviations of theoretical results from experimental results demonstrates that the presented theoretical model exhibits a rational estimation of the reserved energy in these fabrics. 相似文献