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101.
Syed Jafar Mehdi Hector Rosas-Hernandez Elvis Cuevas Susan M. Lantz Steven W. Barger Sumit Sarkar Merle G. Paule Syed F. Ali Syed Z. Imam 《International journal of molecular sciences》2016,17(9)
Currently, the lack of new drug candidates for the treatment of major neurological disorders such as Parkinson’s disease has intensified the search for drugs that can be repurposed or repositioned for such treatment. Typically, the search focuses on drugs that have been approved and are used clinically for other indications. Kinase inhibitors represent a family of popular molecules for the treatment and prevention of various cancers, and have emerged as strong candidates for such repurposing because numerous serine/threonine and tyrosine kinases have been implicated in the pathobiology of Parkinson’s disease. This review focuses on various kinase-dependent pathways associated with the expression of Parkinson’s disease pathology, and evaluates how inhibitors of these pathways might play a major role as effective therapeutic molecules. 相似文献
102.
Mehdi Koohmishi 《Soils and Foundations》2019,59(6):2265-2278
The aggregate in the ballast layer of the railway track structure degrades due to the splitting of single particles and the abrasion of the angular corners, resulting in a ballast course comprised of degraded aggregate with a lower drainage potential. In the present study, the hydraulic conductivity of clean, degraded and clay-fouled degraded ballast specimens was evaluated considering the initial particle size distribution of aggregate and the degradation mechanism to investigate the permeability of ballast fouled by both internal and external factors. First, degraded ballast aggregate was generated by using a large-scale impact loading testing apparatus. Then, a large-scale constant head permeability test was performed to estimate the hydraulic conductivity of degraded ballast aggregate contaminated with clay. Based on the obtained results, the flow regime through extremely degraded ballast remained between a completely turbulent regime (observed in the case of clean ballast) and a laminar flow regime. Darcy’s law was shown to be valid for degraded aggregate samples contaminated with clay. While the degradation of the aggregate had the expected effect of reducing hydraulic conductivity, the abrasion of asperities was shown to have an even greater impact on hydraulic conductivity. Also, the further degradation of aggregate under impact loading was shown to accelerate the reduction in the permeability of clay-fouled degraded ballast to an unacceptable extent. 相似文献
103.
Sanaz Naghibi Hamid Reza Madaah Hosseini Mohammad Ali Faghihi Sani Mohammad Ali Shokrgozar Morteza Mehrjoo 《Ceramics International》2014
TiO2 nanoparticles (NPs) were synthesized by hydrothermal assisted sol–gel technique. In the next step, as-synthesized NPs were modified by poly ethylene glycol (PEG). Then, folic acid (FA) was conjugated to TiO2–PEG. Finally, Doxorubicin (Dox) as an anticancer drug was loaded on as-prepared TiO2–PEG–FA nanocarrier. The optimization of TiO2 and FA concentration and the influence of ultraviolet (UV) irradiation on photocatalytic activity of nanocarrier and Dox loaded carrier were assessed by utilizing the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT)-assay method. 相似文献
104.
Ahmad Hosseini-Bandegharaei Mohammad Karimzadeh Masoud Sarwghadi Aliasghar Heydarbeigi Seyyed Hossein Hosseini Mehdi Nedaie Hassan Shoghi 《Chemical Engineering Research and Design》2014
Adsorption of Pb(II) ion by a novel extractant-impregnated resin, EIR, was studied as a function of various experimental parameters using batch adsorption experiments. The new EIR was prepared by impregnating gallocyanine (GCN) onto Amberlite XAD-16 resin beads. The EIR was characterized by nitrogen analysis and SEM micrographs. The new EIR showed excellent selectivity factor values (α) for Pb(II) adsorption respect to other metal ions. The effects of some chemical and physical variables were evaluated and the optimum conditions were found for Pb(II) removal from aqueous solutions. The equilibrium adsorption isotherm was fitted with the Langmuir adsorption model. The maximum adsorption capacity (qmax) of EIR for Pb(II) ions was found to be 367.92 mg g−1. The kinetic studies showed that the intra-particle diffusion is the rate-controlling step. Also, the intra-particle diffusion coefficients, Dip values, were of the order of 10−12 m2 s−1. The values of enthalpy (ΔH°) were positive, which confirms the endothermic nature of adsorption process. Also, the positive entropy changes (ΔS°) were showed that the randomness increased along with the adsorption process. In addition, the obtained negative values of Gibbs free energy (ΔG°) indicated feasible and spontaneous nature of the adsorption process at different temperatures. The new adsorbent was very stable so that it can be successfully used for many consecutive cycles without significant loss in its adsorption capacity. 相似文献
105.
Sevda Dehghani Ahad Hanifpour Mehdi Nekoomanesh-Haghighi Samahe Sadjadi Seyed Amin Mirmohammadi Ali Farhadi Naeimeh Bahri-Laleh 《应用聚合物科学杂志》2020,137(22):49018
The main aim of this research is to decrease the amount of AlCl3 content that is very corrosive and hazardous in the catalytic system, required for the α-olefin oligomerization without substantial change of final oil features. This was successfully achieved by supporting AlCl3 on different carriers. More precisely, a series of supported bimetallic catalysts was synthesized by immobilization of AlCl3 and TiCl4 onto Al2O3, SiO2, and mixed supports, that is, Al2O3/FeCl3 and SiO2/FeCl3. It was found that silica and alumina-based catalysts had higher catalytic activities compared to support free AlCl3; however, this enhancement for silica-based supports was more significant. According to gel permeation chromatography (GPC) results, the use of single supports, that is, Al2O3 and SiO2, increased oligomer's molecular weight, while the application of mixed supports resulted in the decrease of molecular weight of the oligomers. Viscosity characteristics of the synthesized oligomers have also been studied at two different temperatures of 40 and 100°C (KV40 and KV100). The viscosity index (VI) values, derived from KV40 and KV100, of the prepared oligomers were in the range of 126–145. The molecular weight and termination mechanisms of the oligomers were studied by 1H-NMR spectroscopy. The obtained results disclosed that the employed reaction conditions led to the production of oligomer chains with various structures including vinylidene (Vd), and di and three-substituted vinylene (2Vn, 3Vn) structures. 相似文献
106.
Mohammad Shayan Asenjan Seyed Ali Reza Sabet Mehdi Nekoomanesh 《Iranian Polymer Journal》2020,29(4):301-307
This research explores mechanical and high velocity impact response of hybrid long carbon/glass fiber-reinforced polypropylene thermoplastic composites (HLFT) with different fiber lengths. The work examines three hybrid long fiber thermoplastic composites, i.e., 5, 10 and 20 mm. The HLFTs were prepared by a combination of extrusion and pultrusion processes and using a cross-head die. Tensile and Izod impact tests were carried out to evaluate the mechanical performance of each HLFT compound. A gas gun with a spherical projectile was used to conduct high velocity impact tests at three velocities of 144, 205 and 240 m/s. The results showed that internal mixing operation caused extensive reduction in fiber length of all three LFT lengths. Tensile strength, modulus and Izod impact test results were the indications of higher values with increase in HLFT length. Comparison of these results for the HLFT with that of corresponding glass/PP LFTs, adopted from earlier work by Shayan Asenjan et al. (J Compos Mater 53:353–360, 2019), showed better performance of HLFT. The high velocity impact results showed a steady higher impact performance with the increase in HFLT fiber length for all impact velocities tested. Comparison of HLFT high velocity impact performance revealed better results for all impact velocities tested with that of the corresponding glass/PP LFT composite. 相似文献
107.
The present study is concerned with the computational fluid dynamics(CFD) simulation of turbulent dispersion of immiscible liquids, namely, water–silicone oil and water–benzene through Kenics static mixers using the Eulerian–Eulerian and Eulerian–Lagrangian approaches of the ANSYS Fluent 16.0 software. To study the droplet size distribution(DSD), the Eulerian formulation incorporating a population balance model(PBM) was employed. For the Eulerian–Lagrangian approach, a discrete phase model(DPM) in conjunction with the Eulerian approach for continuous phase simulation was used to predict the residence time distribution(RTD) of droplets.In both approaches, a shear stress transport(SST) k-ω turbulence model was used. For validation purposes, the simulated results were compared with the experimental data and theoretical values for the Fanning friction factor, Sauter mean diameter and the mean residence time. The reliability of the computational model was further assessed by comparing the results with the available empirical correlations for Fanning friction factor and Sauter mean diameter. In addition, the influence of important geometrical and operational parameters, including the number of mixing elements and Weber number, was studied. It was found that the proposed models are capable of predicting the performance of the Kenics static mixer reasonably well. 相似文献
108.
109.
Introducing a specific clean extraction procedure with a minimal matrices effect for food colorant determination is still a challengeable topic and highly recommended. Mixed hemimicelle solid-phase extraction method, based on cetyltrimethylammonium bromide-coated Fe3O4/SiO2 nanoparticles as a novel, simple, and fast preconcentration method, was applied for preconcentration and fast isolation of three synthetic food colorants in foodstuff matrices prior to HPLC-UV-vis determination. The influence of different parameters on extraction efficiency such as surfactant amount, sample pH, time of extraction, desorption condition, and nanoparticles concentration was optimized. Under the optimized conditions, a preconcentration factor of 100 was achieved by extracting 10 mL sample. The limit of detection for the three synthetic food colorants including Tartrazine, Sunset yellow FCF, and Quinoline yellow is 2.50, 1.25, and 2.12 μg/L, respectively. The proposed method was applicable for extraction and preconcentration of three food colorants in various food samples with the food dye contents in the range of 13–105 μg/L. 相似文献
110.
The novel conductive nanocomposite has been successfully prepared by emulsion polymerization. First, magnetite nanoparticles were synthesized via coprecipitation reaction. Then, poly (indole-co-thiophene)@Fe3O4 nanocomposite was prepared via emulsion copolymerization of indole and thiophene monomers using sodium dodecyl sulfate as an emulsifier and ammonium persulfate as an oxidant in the presence of Fe3O4 nanoparticles. Characterization of the synthesized copolymer, Poly (In-co-T), and its magnetic nanocomposite were studied by Fourier transform infrared spectra, X-ray diffraction, scanning electron microscopy, thermal gravimetric analysis, differential scanning calorimetric, UV-vis spectrophotometer, and vibrating sample magnetometer. Also, the electrical conductivity of copolymer and nanocomposite were determined by four-probe instrument. Results showed a synergic effect in thermal stability by good interaction between polymer chain and magnetic nanoparticles. The conductivity of the nanocomposite was higher than bare copolymer, and increase of nanoparticles content caused an increment in the conductivity of the nanocomposites. The applicable properties of proposed conductive nanocomposite as a base at electrochemical biosensing have been investigated. 相似文献