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51.
Wei Zhu Jimin Guo Shahrouz Amini Yi Ju Jacob Ongudi Agola Andreas Zimpel Jin Shang Achraf Noureddine Frank Caruso Stefan Wuttke Jonas G. Croissant C. Jeffrey Brinker 《Advanced materials (Deerfield Beach, Fla.)》2019,31(25)
Creating a synthetic exoskeleton from abiotic materials to protect delicate mammalian cells and impart them with new functionalities could revolutionize fields like cell‐based sensing and create diverse new cellular phenotypes. Herein, the concept of “SupraCells,” which are living mammalian cells encapsulated and protected within functional modular nanoparticle‐based exoskeletons, is introduced. Exoskeletons are generated within seconds through immediate interparticle and cell/particle complexation that abolishes the macropinocytotic and endocytotic nanoparticle internalization pathways that occur without complexation. SupraCell formation is shown to be generalizable to wide classes of nanoparticles and various types of cells. It induces a spore‐like state, wherein cells do not replicate or spread on surfaces but are endowed with extremophile properties, for example, resistance to osmotic stress, reactive oxygen species, pH, and UV exposure, along with abiotic properties like magnetism, conductivity, and multifluorescence. Upon decomplexation cells return to their normal replicative states. SupraCells represent a new class of living hybrid materials with a broad range of functionalities. 相似文献
52.
Sasan?Amini Kristian?Beckers Markus?B?hm Fritz?Busch Nihan?Celikkaya Vittorio?Cozzolino Anne?Faber Michael?Haus Dominik?Huth Alfons?Kemper Andreas?Kipf Helmut?Krcmar Florian?MatthesEmail author J?rg?Ott Christian?Prehofer Alexander?Pretschner ?mer?Uluda? Wolfgang?W?rndl 《Informatik-Spektrum》2017,40(2):180-191
53.
Zhiyuan Dong Guofeng Zhang Nina H. Amini 《International Journal of Adaptive Control and Signal Processing》2018,32(3):528-546
The single‐photon quantum filtering problems have been investigated recently with applications in quantum computing. In practice, the detector responds with a quantum efficiency of less than unity since there exists some mode mismatch between the detector and the system and the single‐photon signal may be corrupted by quantum white noise. Consequently, quantum filters based on multiple measurements are designed in this paper to improve estimation performance. More specifically, the filtering equations for a 2‐level quantum system driven by a single‐photon input state and under multiple measurements are presented in this paper. Four scenarios, ie, (1) 2 diffusive measurements with Q‐P quadrature form, (2) 2 diffusive measurements with Q‐Q quadrature form, (3) diffusive plus Poissonian measurements, and (4) 2 Poissonian measurements, are considered. It is natural to compare the filtering results, ie, measuring a single channel or both channels, which one is better? By the simulation where we use a single photon to excite an atom, it seems that multiple measurements enable us to excite the atom with higher probability than only measuring a single channel. In addition, a measurement back‐action phenomenon is revealed by the simulation results. 相似文献
54.
Physicochemical stability of calcium alginate beads immobilizing TiO2 nanoparticles for removal of cationic dye under UV irradiation 下载免费PDF全文
Recently, there have been considerable interests to immobilize photocatalyst in alginate beads for removing pollutants from water sources. However, the feasibility of using alginate beads in industry largely depends on its long‐term stability during operation. This study investigated the physicochemical stability of alginate/titanium dioxide beads (Alg/TiO2) when exposed to UV irradiation in aqueous environment. The degradation of Alg/TiO2 beads was evident because the diameter and mass of the beads was reduced by 12% and 40%, respectively, after 120 h of irradiation. A substantial amount of TiO2 was leached into the external medium. Consequently, the removal efficiency of model cationic dye was found to reduce after every process cycle. Morphological analysis showed the formation of cavities on the surface of the Alg/TiO2 beads. Interestingly, the blank alginate beads degraded more rapidly than the Alg/TiO2 beads, confirming the UV‐shielding effect of TiO2. Nevertheless, this study reveals the need to improve the UV stability of alginate‐based beads before they can be considered for practical application. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45002. 相似文献
55.
Mohammad Mahdi Najafpour Mojtaba Amini Mahdi Ashrafi 《International Journal of Hydrogen Energy》2017,42(12):8539-8544
The problem of finding a way to store energy from abundant sources such as sunlight, wind or geothermal heat is critical. Water splitting toward hydrogen production is a very promising way for the goal. Although the cathodic reaction is of major interest in hydrogen production, the concurrent anodic water oxidation, which provides cheap electrons for the cathodic reaction, is a limitation for hydrogen formation. The best water-oxidizing catalyst was found by Nature million years ago and used in plants, algae and cyanobacteria. We believe learning from the natural system is very promising, because Nature has been successfully splitting water for millions of years, using an inexpensive and environmentally friendly MnCa oxido cluster. Herein we study the phenol oxidation by some nano-sized metal oxides in the presence of H2O2. As metal oxides are functional and structural models for the water-oxidizing complex in Photosystem II, the results can be expanded for the natural site. We suggest that low organic compound oxidation under water oxidation is an important issue to select manganese and calcium ions for water oxidation. 相似文献
56.
S. Amini N. D. Maines 《International journal for numerical methods in engineering》1998,41(5):875-898
Discretization of boundary integral equations leads, in general, to fully populated complex valued non-Hermitian systems of equations. In this paper we consider the efficient solution of these boundary element systems by preconditioned iterative methods of Krylov subspace type. We devise preconditioners based on the splitting of the boundary integral operators into smooth and non-smooth parts and show these to be extremely efficient. The methods are applied to the boundary element solution of the Burton and Miller formulation of the exterior Helmholtz problem which includes the derivative of the double layer Helmholtz potential—a hypersingular operator. © 1998 John Wiley & Sons, Ltd. 相似文献
57.
S. J. Sadjadi M. Jafari T. Amini 《The International Journal of Advanced Manufacturing Technology》2009,44(1-2):194-200
The idea of Milk Run has been used in the context of logistic and supply chain problems in order to manage the transportation of materials. In this paper, we propose a new Milk Run method, as a mixed integer approach, to manage supply chain problems. Since the resulted problem formulation is NP-Hard, we use some meta-heuristic and compare the results with the optimal solutions of the proposed Milk Run method. The mathematical modeling of this paper is purposely customized for a special case of an auto industry. We implement the mathematical formulation and the meta-heuristic using some actual data and compare the results with the current strategy. The preliminary results indicate that the proposed method could provide a practical tool to significantly reduce the cost of logistic. 相似文献
58.
Mohammad Reza Nabid Maryam Golbabaee Abdolmajid Bayandori Moghaddam Ali Reza Mahdavian Mostafa Mohammadpour Amini 《Polymer Composites》2009,30(6):841-846
Peroxidase-catalyzed template-guided polymerization of aniline in the presence of γ- alumina nanosheet (NS) particles have been carried out in aqueous media and γ-Al2O3/PANI nanocomposite was obtained. The polymerization of aniline occurred in aqueous solution in the presence of SPS (sulfonated polystyrene) as a template and SDS (sodium dodecyl sulfate) as a surfactant. Both obtained nanocomposites were comparable by SEM images. It was demonstrated that the γ-Al2O3 NS/PANI-SPS nanocomposite has higher conductivity and the γ-Al2O3 NS/PANI-SDS nanocomposite has higher void areas. The higher conductivity of γ-Al2O3 NS/PANI-SPS nanocomposite is attributed to the higher coated areas of γ-Al2O3 NS during polymerization in comparison with γ-Al2O3 NS/PANI-SDS which are not coated efficiently as the former. The FT-IR studies showed that the γ-Al2O3 NS/PANI nanocomposite was formed by interaction of the polyaniline (PANI) and γ-Al2O3 NS. FTIR also showed that the amount of PANI in γ-Al2O3 NS/PANI-SPS is more than in γ-Al2O3 NS/PANI-SDS. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers 相似文献
59.
Maghsoudy Soroush Doulati Ardejani Faramarz Molson John Amini Mehdi Ebrahimi Luna 《Mine Water and the Environment》2019,38(1):197-212
Mine Water and the Environment - A shortcoming of the heap leaching process is its inherent limited metal recovery rate, due primarily to preferential pathways, which reduces the efficiency of the... 相似文献
60.
The new nanohybrid of molybdenum peroxo compounds based on pyridine dicarboxylate ligands were synthesized by employing one-pot procedure in aqueous media and characterized by infrared (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal analysis (TGA/DTA). The prepared compounds were used as catalysts for the epoxidation of cyclohexene and cyclooctene in a mild condition. Results showed that these molybdenum peroxo compounds have significant potentials as oxidants in oxygen atom transfer reactions. These reagents oxidized olefins to epoxides in presence of hydrogen peroxide with high conversions and selectivity. Comparison of the relative reactivity of those compounds shows that the electronic nature of ligands influences the rate and activity of oxygen transfer reaction. It is also found that the addition of organic ligands not only prevented the formation of diols in epoxidation of alkenes, but also increased the reaction rate. 相似文献