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941.
Melamine–formaldehyde–thiourea (MFT) chelating resin has been prepared. Au3+ ions uptake behavior and selectivity of the chelating resin were investigated by both batch and column methods. MFT resin showed higher affinity toward Au3+ compared with base metal ions, Cu2+ and Zn2+. The highest Au3+ uptake values were obtained at pH 2 and Au3+ adsorption capacity of the resin was calculated as 48 mg Au3+/g resin (0.246 mmol Au3+/g resin) by batch method. It was concluded that Au3+ ions could be selectively concentrated from the solution including Cu2+ and Zn2+ base metal ions by column method. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
942.
Zeolite was used as a low-cost adsorbent to evaluate its ability to remove color from textile effluents. The zeolit (clinoptilolite) used in this study is a natural clay mineral from the Gbrdes region of Turkey. The adsorption of reactive dyes into zeolite was investigated by a series of batch adsorption experiments. Three reactive dyes (Everzol Black, Everzol Red, Everzol Yellow) were used in laboratory studies. Adsorption test were carried out as a function of solids concentration, conditioning time and dye concentration. The degree of hydrophilicity was found to play an important role in the uptake of reactive dyes. The adsorption results indicated that natural zeolite has a limited adsorption capacity for reactive dyes but can be distinctly improved by modifying its surfaces with quaternary amines. A comparison of natural and modified zeolites at 5% solids concentration indicated that, while the adsorption densities of dyes with natural zeolite yielded negative or slightly positive values, those with modified zeolite gave adsorption densities in the range of 2.9 to 7.6 mg/g. 相似文献
943.
Mehmet Kanbay Laura Tapoi Carina Ureche Mustafa C. Bulbul Irem Kapucu Baris Afsar Carlo Basile Adrian Covic 《Hemodialysis international. International Symposium on Home Hemodialysis》2021,25(3):288-299
The most significant complication of end-stage kidney disease (ESKD) is cardiovascular disease, mainly coronary artery disease (CAD). Although the effective treatment of CAD is an important prognostic factor, whether percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) is better for treating CAD in this group of patients is still controversial. We searched Pubmed/Medline, Web of Science, Embase, the Cochrane Central Register of Controlled Trials articles that compared the outcomes of CABG versus PCI in patients with ESKD requiring dialysis. A total of 10 observational studies with 39,666 patients were included. Our analysis showed that when compared to PCI, CABG had lower risk of need for repeat revascularization (relative risk [RR] = 2.25, 95% confidence interval [CI] 2.1–2.42, p < 0.00001) and cardiovascular death (RR = 1.19, 95% CI 1.14–1.23, p < 0.00001) and higher risk for short-term mortality (RR = 0.43, 95% CI 0.38–0.48, p < 0.00001). There was no statistically significant difference between the PCI and CABG groups in the risk for late mortality (RR = 1.05, 95% CI 0.97–1.14, p = 0.25), myocardial infarction (RR = 1.05, 95% CI 0.46–2.36, p = 0.91) or stroke (RR = 1.02, 95% CI 0.64–1.61, p = 0.95). This meta-analysis showed that in ESKD patients requiring dialysis, CABG was superior to PCI in regard to cardiovascular death and need for repeat revascularization and inferior to PCI in regard to short term mortality. However, this meta-analysis has limitations and needs confirmation with large randomized controlled trials. 相似文献
944.
Abdullah Thamer Adnan Juzsakova Tatjana Hafad Sanaa A. Rasheed Rashed Taleb Al-Jammal Noor Mallah Muhammad Ali Salman Ali Dawood Le P. C. Domokos Endre Aldulaimi Mustafa 《Clean Technologies and Environmental Policy》2022,24(2):519-541
The growing global economy resulted in an incessant increase in transportation and exploitation of oil. Hence, the oil spillage has been considered a serious threat to aquatic and terrestrial ecosystems. Therefore, water purification has been considered a major challenge around the world. There are numerous classical methods available for oil removal from water, but owing to multiple defects and disadvantages, research efforts have focused to find such adsorbents which can improve oil adsorption capability. Traditional adsorbent material typically applied in oil removal includes activated carbon, organoclays, wool, zeolites, etc. These materials suffer from several drawbacks such as low absorption capacity, non-selective absorption, and complicated reusability, whereas nano-adsorbents offer multiple advantages such as having multiple sorption sites, large surface area, short intra-particle diffusion distance, tuneable pore size, and ease of low-temperature modification. Multi-walled carbon nanotubes (MWCNTs) are extensively used adsorbent materials with a strong affinity for the removal of organic pollutants. The functionalization MWCNTs further increase the sorption capacity of adsorbents manifolds to remove organic materials. These nanocomposites are also compatible with green materials and considered environmentally friendly adsorbents. This review paper aims at providing an insight to understand the properties of the MWCNTs and their potential use to adsorb hydrocarbons from water. Moreover, the synthesis methods of those materials, their modification procedures including the functionalization with metal oxide nanoparticles, and applications are also discussed in detail.
Graphic abstract945.
Nadeem Qaiser Asrar Nabil Damdam Sherjeel Munsif Khan Saleh Bunaiyan Muhammad Mustafa Hussain 《Advanced functional materials》2021,31(7):2007445
Stretchable electronics can be used for numerous advanced applications such as soft and wearable actuators, sensors, bio-implantable devices, and surgical tools because of their ability to conform to curvilinear surfaces, including human skin. The efficacy of these devices depends on the development of stretchable geometries such as interconnection-based configurations and the associated mechanics that helps to achieve optimum configurations. This work presents the essential mechanics of silicon (Si) island-interconnection structures, which include horseshoe and spiral interconnections, without reducing the areal efficiency. In particular, this study demonstrates the range of the geometrical parameters where they have a high stretchability and cyclic life. The numerical results predict the areas that are prone to breaking followed by experimental validation. The figure-of-merit for these configurations is achieved by mapping the fracture-free zones for in-plane and out-of-plane stretching with essential implications in stretchable and wearable system design. Furthermore, this work demonstrates the mechanical response for a range of materials (i.e., copper, gold, aluminum, silver, and graphene) that experience the plastic deformations in contrast to conventionally used Si-based devices that represent the extended usage for advanced stretchable electronic devices. The detailed mechanics of these configurations provides comprehensive guidelines to manufacture wearable and stretchable electronic devices. 相似文献
946.
Wafa Mustafa Saleh;Esam Bashir Yahya;Mardiana Idayu Ahmad;H. P. S. Abdul Khalil; 《Polymer Engineering and Science》2024,64(8):3993-4001
This study investigates the development and characterization of chitosan, gelatin, and chitosan/gelatin (Chi/Gel) bioaerogel composites through a facile and eco-friendly approach. The goal is to optimize their structural and functional properties for potential environmental and biomedical applications. Direct freezing and lyophilization approach were used to prepare the aerogels, the focus was on investigating the effects of blending ratios on the density, porosity, surface area, and water absorption capabilities of the aerogels. The results show that Chi/Gel 60/40 composition achieved an optimal balance of structural robustness and functional performance, characterized by a moderate density of 74.2 mg/cm3, the highest porosity among the samples at 93.5%, an impressive surface area of 184.8 m2/g, and a water absorption capacity of 28.8 g/g. These results suggest that the synergistic effect of chitosan and gelatin at specific ratios significantly enhances the overall properties of the material. Our findings suggest that Chi/Gel bioaerogels, especially the 60/40 composite, hold great promise for diverse applications. 相似文献
947.
Huseyİn Avnİ Kırmacı Barbaros Hamdİ Özer Mustafa Akçelik Nefise Akçelİk 《International Journal of Dairy Technology》2016,69(2):301-307
In this study, characterisation of dominant strains of lactic flora in traditional Urfa cheese made from sheep's milk was performed using biochemical, phenotypic and genotypic methods. According to the results obtained, the percentage distributions of the lactic acid bacteria isolated were as follows: 48.95% Enterococcus spp., 40.55% Lactococcus spp., 9.10% Lactobacillus spp., 0.69% Streptococcus spp. and 0.69% Leuconostoc spp. The majority of lactococcal isolates showed an atypical phenotype of growing in the presence of 6.5% NaCl. Acidification and bacteriocin production were also determined for each isolate. Four strains showed bacteriocin activity. 相似文献
948.
949.
950.
In a production flow line with stochastic environment, variability affects the system performance. These stochastic nature of real-world processes have been classified in three types: arrival, service and departure process variability. So far, only service process – or task time – variation has been considered in assembly line (AL) balancing studies. In this study, both service and flow process variations are modelled along with AL balancing problem. The best task assignment to stations is sought to achieve the maximal production. A novel approach which consists of queueing networks and constraint programming (CP) has been developed. Initially, the theoretical base for the usage of queueing models in the evaluation of AL performance has been established. In this context, a diffusion approximation is utilised to evaluate the performance of the line and to model the variability relations between the work stations. Subsequently, CP approach is employed to obtain the optimal task assignments to the stations. To assess the effectiveness of the proposed procedure, the results are compared to simulation. Results show that, the procedure is an effective solution method to measure the performance of stochastic ALs and achieve the optimal balance. 相似文献