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101.
Yousef Kazemzadeh Behnam Dehdari Zahra Etemadan Masoud Riazi Mohammad Sharifi 《石油科学(英文版)》2019,(3):578-590
Nanofluids because of their surface characteristics improve the oil production from reservoirs by enabling different enhanced recovery mechanisms such as wettability alteration, interfacial tension (IFT) reduction, oil viscosity reduction, formation and stabilization of colloidal systems and the decrease in the asphaltene precipitation. To the best of the authors’ knowledge, the synthesis of a new nanocomposite has been studied in this paper for the first time. It consists of nanoparticles of both SiO2 and Fe3O4. Each nanoparticle has its individual surface property and has its distinct effect on the oil production of reservoirs. According to the previous studies, Fe3O4 has been used in the prevention or reduction of asphaltene precipitation and SiO2 has been considered for wettability alteration and/or reducing IFTs in enhanced oil recovery. According to the experimental results, the novel synthesized nanoparticles have increased the oil recovery by the synergistic effects of the formed particles markedly by activating the various mechanisms relative to the use of each of the nanoparticles in the micromodel individually. According to the results obtained for the use of this nanocomposite, understanding reservoir conditions plays an important role in the ultimate goal of enhancing oil recovery and the formation of stable emulsions plays an important role in oil recovery using this method. 相似文献
102.
Zahra Kargarpour Layla Panahipour Richard J. Miron Reinhard Gruber 《International journal of molecular sciences》2022,23(11)
The preparation of platelet-rich fibrin (PRF) requires blood centrifugation to separate the yellow plasma from the red erythrocyte fraction. PRF membranes prepared from coagulated yellow plasma are then transferred to the defect sites to support tissue regeneration. During natural wound healing, however, it is the unfractionated blood clot (UBC) that fills the defect site. It is unclear whether centrifugation is necessary to prepare a blood-derived matrix that supports tissue regeneration. The aim of the present study was to compare lysates prepared from PRF and UBC based on bioassays and degradation of the respective membranes. We report here that lysates prepared from PRF and UBC membranes similarly activate TGF-β signaling, as indicated by the expression of interleukin 11 (IL-11), NADPH oxidase 4 (NOX-4) and proteoglycan 4 (PRG4) in gingival fibroblasts. Consistently, PRF and UBC lysates stimulated the phosphorylation and nuclear translocation of Smad3 in gingival fibroblasts. We further observed that PRF and UBC lysates have comparable anti-inflammatory activity, as shown by the reduction in lipopolysaccharide (LPS)-induced IL-6, inducible nitric oxidase synthase (iNOS) and cyclooxygenase 2 (COX-2) expression in RAW264.7 cells. Moreover, inflammation induced by Poly (1:C) HMW and FSL-1, which are agonists of Toll-like receptor (TLR) 3 and 2/6, respectively, was reduced by both PRF and UBC. PRF and UBC lysates reduced the nuclear translocation of p65 in LPS-induced RAW264.7 cells. In contrast to the similar activity observed in the bioassays, UBC membranes lack the structural integrity of PRF membranes, as indicated by the rapid and spontaneous disintegration of UBC membranes. We show here that the lysates prepared from PRF and UBC possess robust TGF-β and anti-inflammatory activity. However, visual inspection of the PRF and UBC membranes confirmed the negative impact of erythrocytes on the structural integrity of membranes prepared from whole blood. The data from the present study suggest that although both UBC and PRF have potent TGF-β and anti-inflammatory activity, UBC does not have the strength properties required to be used clinically to prepare applicable membranes. Thus, centrifugation is necessary to generate durable and clinically applicable blood-derived membranes. 相似文献
103.
Zahra Bakhtiary Jaleh Barar Ayuob Aghanejad Amir Ata Saei Elhameh Nemati 《Drug development and industrial pharmacy》2017,43(8):1244-1253
Non-small cell lung cancer (NSCLC) patients with sensitizing mutations in the exons 18–21 of the epithelial growth factor receptor (EGFR) gene show increased kinase activity of EGFR. Hence, tyrosine kinase inhibitors (TKIs) such as erlotinib (ETB) have commonly been used as the second line therapeutic option for the treatment of metastatic NSCLC. While the ETB is available as an oral dosage form, the local delivery of this TKI to the diseased cells of the lung may ameliorate its therapeutic impacts. In the current study, we report on the development of ETB-loaded solid lipid nanoparticle (SLN) based formulation of dry powder inhaler (ETB-SLN DPI). ETB-SLNs were formulated using designated amount of compritol/poloxamer 407. The engineered ETB-SLNs showed sub-100?nm spherical shape with an encapsulation efficiency of 78.21%. MTT assay and DAPI staining revealed that the ETB-SLNs enhanced the cytotoxicity of cargo drug molecules in the human alveolar adenocarcinoma epithelial A549 cells as a model for NSCLC. To attain the ETB-SLN DPI, the ETB-SLNs were efficiently spray dried into microparticles (1–5?μm) along with mannitol. The ETB-SLN DPI powder displayed suitable flowability and aerodynamic traits. The Carr's Index, Hausner ratio and Next Generation Impactor (NGI) analyses confirmed deep inhalation pattern of the formulation. Based on these findings, we propose the ETB-SLN DPI as a promising treatment modality for the NSCLC patients. 相似文献
104.
Alireza Ahmadiparidari Robert E. Warburton Leily Majidi Mohammad Asadi Amir Chamaani Jacob R. Jokisaari Sina Rastegar Zahra Hemmat Baharak Sayahpour Rajeev S. Assary Badri Narayanan Pedram Abbasi Paul C. Redfern Anh Ngo Mrton Vrs Jeffrey Greeley Robert Klie Larry A. Curtiss Amin Salehi‐Khojin 《Advanced materials (Deerfield Beach, Fla.)》2019,31(40)
Lithium–CO2 batteries are attractive energy‐storage systems for fulfilling the demand of future large‐scale applications such as electric vehicles due to their high specific energy density. However, a major challenge with Li–CO2 batteries is to attain reversible formation and decomposition of the Li2CO3 and carbon discharge products. A fully reversible Li–CO2 battery is developed with overall carbon neutrality using MoS2 nanoflakes as a cathode catalyst combined with an ionic liquid/dimethyl sulfoxide electrolyte. This combination of materials produces a multicomponent composite (Li2CO3/C) product. The battery shows a superior long cycle life of 500 for a fixed 500 mAh g?1 capacity per cycle, far exceeding the best cycling stability reported in Li–CO2 batteries. The long cycle life demonstrates that chemical transformations, making and breaking covalent C? O bonds can be used in energy‐storage systems. Theoretical calculations are used to deduce a mechanism for the reversible discharge/charge processes and explain how the carbon interface with Li2CO3 provides the electronic conduction needed for the oxidation of Li2CO3 and carbon to generate the CO2 on charge. This achievement paves the way for the use of CO2 in advanced energy‐storage systems. 相似文献
105.
Scientometrics - We analyzed breakthrough patents that serve as the basis of emerging technological trajectories and paradigm over 25-years. The results showed that although technological fields... 相似文献
106.
Zahra Azimi Aswani Gopakumar Amira S.Ameruddin Li Li Thien Truong Hieu T.Nguyen Hark Hoe Tan Chennupati Jagadish Jennifer Wong-Leung 《Nano Research》2022,(4):3695-3703
Catalyst-free InGaAs nanowires grown by selective area epitaxy are promising building blocks for future optoelectronic devices in the infrared spectral region.D... 相似文献
107.
The versatile chloromethyl TIPNO-based alkoxyamine was efficiently transformed into other valuable functionalised TIPNO-based alkoxyamines such as amino alkoxyamines which are interesting initiators for block copolymers and bisalkoxyamines in good yield and in two steps at the most. One bisalkoxyamine has allowed to prepare well-defined polystyrene-b-poly(n-butyl acrylate)-b-polystyrene symmetrical triblock copolymer. The last representative example of such alkoxyamines is a styrenic alkoxyamine which was copolymerized with styrene to afford branched polystyrene. Finally, for the first time branched poly(n-butyl acrylate) by nitroxide mediated radical polymerization was obtained and was a efficient macroinitiator of styrene, which indicates that the radical polymerization mediated by this styrenic alkoxyamine is living. 相似文献
108.
A. -M. Zahra C. Y. Zahra G. Jaroma-Weiland G. Neuer W. Lacom 《Journal of Materials Science》1995,30(2):426-436
In the framework of the European COST 507 project the specific heat capacities of aluminium alloys and metal matrix composites based thereon have been measured between 20 and 520 °C by differential scanning calorimetry and stored in the databank THERSYST along with other thermophysical properties mainly drawn from literature. The curves show the influence of additional elements and reinforcements, of the fabrication process, thermomechanical treatment and scanning rate on the precipitation and dissolution kinetics of the various metastable phases and their relative amounts. The database may be used to select existing light alloys or elaborate new ones in view of specific technical applications.Dedicated to Professor Dr. Hans Löffler on the occasion of his 72nd birthday. 相似文献
109.
Naveh-Benjamin Moshe; Hussain Zahra; Guez Jonathan; Bar-On Maoz 《Canadian Metallurgical Quarterly》2003,29(5):826
This study further tested an associative-deficit hypothesis (ADH; M. Naveh-Benjamin, 2000), which attributes a substantial part of older adults' deficient episodic memory performance to their difficulty in merging unrelated attributes-units of an episode into a cohesive unit. First, the results of 2 experiments replicate those observed by M. Naveh-Benjamin (2000) showing that older adults are particularly deficient in memory tests requiring associations. Second, the results extend the type of stimuli (pictures) under which older adults show this associative deficit. Third, the results support an ADH in that older adults show less of an associative deficit when the components of the episodes used are already connected in memory, thereby facilitating their encoding and retrieval. Finally, a group of younger adults who encoded the information under divided-attention conditions did not show this associative deficit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.