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排序方式: 共有519条查询结果,搜索用时 500 毫秒
21.
Mitsuhiro Shikida Tatsuaki Sugito Mina Okochi Hiroyuki Honda 《Microsystem Technologies》2014,20(2):315-323
Reaction performance of a droplet-based biochemical assay technique that uses magnetic wires as sample carriers is evaluated. Wires 2.0 mm in length, 0.05 mm in width, and 0.02 mm in thickness are fabricated by chemical etching, introduced into a droplet immersed in oil, and manipulated by the magnetic force of a moving magnet. Alkaline-phosphatase as an enzyme is immobilized on the wire surfaces by applying Au and self-assembled monolayer coatings, and the method’s on-chip reaction performance is evaluated. The enzymatic reaction is found to increase linearly as the number of wires and the reaction time increase. Relatively high performance reproducibility for enzymatic reactions is obtained; on average, the reaction absorbance, standard deviation, and coefficient of variance are found to be respectively 1.14, 0.103, and 9.1 %. The conductivity change in a fused droplet is used to evaluate the absolute volume of liquid transferred with the extracted wires and a value of 0.33 μl is obtained. 相似文献
22.
We herein advance the application of a two-dimensional (2D) photonic crystal (PC) as a window layer in an efficient polymer solar cell (PSC). The PSC used here consisted of a photovoltaic (PV) layer of poly(3-hexylthiophene): methanofullerene bulk-heterojunction with a planarized 2D PC window layer made of a hexagonal array of columns of SiO2 nano-rods embedded in a dielectric layer of SiNx. By means of a theoretical simulation of the 2D PCs using a finite-difference time-domain (FDTD) method, it was shown that the path length of the incident light can be increased with a large deflection angle. The experimental results confirmed the simulated results obtained using the 2D PC layer. Furthermore, it was shown that a relative increase in power conversion efficiency (PCE) of about 25% was achieved for the PSC with the 2D PC layer, indicating that this layer induces further photon absorption due to efficient light-harvesting within the PV layer. 相似文献
23.
Many polymeric materials have been developed and introduced for bone regeneration. Especially, their nanofibrous forms are mostly applied for artificial extracellular matrices. Polymeric materials in their nanofibrous form show some potent properties such as high surface‐to‐volume ratio, tunable porosity, and ease of surface functionalization. Benefiting from the properties of their main polymer and additives, they can provide new opportunities for cell seeding, proliferation, and new 3D‐tissue formation. This article focuses on most cited polymeric nanofibrous scaffolds fabricated by electrospinning and recent achievements. They were divided into two main categories: natural (collagen, silk, keratin, gelatin, chitosan, and alginate) and synthetic (e.g., polycaprolactone, polylactic acid, and polyglycolic acid) polymers. The role of several additives like hydroxyapatite, bone morphogenetic proteins (BMPs), tricalcium phosphate, and collagen type I in improving the adhesion, differentiation, and tissue formation of stem cells were discussed. Finally, the osteogenic capacity and ability of nanofibrous scaffolds to support the growth of clinically relevant bone tissue were briefly studied. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42883. 相似文献
24.
A prism coupler based plasmonic sensor consisting of a prism, gold (Au) metal film and dielectric sample has been investigated with the use of admittance loci method in wavelength interrogation mode. Prism materials namely fused silica, chalcogenide (2S2G) and silicon have been used to study their effect on surface plasmon sensing in wavelength interrogation mode by admittance loci plots and by corresponding surface plasmon sensing curves. The performance of the plasmonic sensor under wavelength interrogation mode based on the choice of the prism material has been discussed and validated by the dynamic range and sensitivity plots. 相似文献
25.
Hsi-Wu Wong Mina Jun Jay Peck Ian A. Waitz Richard C. Miake-Lye 《Aerosol science and technology》2014,48(9):981-995
The development of a detailed microphysical model that describes the complex multicomponent interactions between organic vapors and soot particles emitted from aircraft gas turbine engines is presented. Our model formulation includes both soot surface activation by organic vapors and organic vapor condensation on the activated part of the soot surfaces. To enable this formulation, approaches to estimate chemical and physical properties of aerosols containing complex mixtures of sulfuric acid, water, and organic molecules were developed. Relevant distributions of a list of organic surrogates at the engine exit plane were used to represent complex organic emissions from aircraft engines. A parametric study was performed using this new formulation to understand the effects of ambient conditions, organic emissions levels, and mass accommodation coefficient values on the evolution of near field volatile particulate matter emissions from aircraft engines at ground level.
Copyright 2014 American Association for Aerosol Research 相似文献
26.
Mina Han Ikue Abe Jihun Oh Jaehoon Jung Young Ji Son Jaegeun Noh Mitsuo Hara Takahiro Seki 《International journal of molecular sciences》2022,23(2)
Fluorescent molecular assembly systems provide an exciting platform for creating stimuli-responsive nano- and microstructured materials with optical, electronic, and sensing functions. To understand the relationship between (i) the plausible molecular structures preferentially adopted depending on the solvent polarity (such as N,N-dimethylformamide [DMF], tetrahydrofuran [THF], and toluene), (ii) the resulting spectroscopic features, and (iii) self-assembled nano-, micro-, and macrostructures, we chose a sterically crowded triangular azo dye (3Bu) composed of a polar molecular core and three peripheral biphenyl wings. The chromophore changed the solution color from yellow to pink-red depending on the solvent polarity. In a yellow DMF solution, a considerable amount of the twisted azo form could be kept stable with the help of favorable intermolecular interactions with the solvent molecules. By varying the concentration of the DMF solution, the morphology of self-assembled structures was transformed from nanoparticles to micrometer-sized one-dimensional (1D) structures such as sticks and fibers. In a pink-red toluene solution, the periphery of the central ring became more planar. The resulting significant amount of the keto-hydrazone tautomer grew into micro- and millimeter-sized 1D structures. Interestingly, when THF-H2O (1:1) mixtures were stored at a low temperature, elongated fibers were stacked sideways and eventually developed into anisotropic two-dimensional (2D) sheets. Notably, subsequent exposure of visible-light-irradiated sphere samples to solvent vapor resulted in reversible fluorescence off↔on switching accompanied by morphological restoration. These findings suggest that rational selection of organic dyes, solvents, and light is important for developing reusable fluorescent materials. 相似文献
27.
封堵性是油基钻井液的一个重要评价指标,提高油基钻井液的封堵性有助于井壁稳定,促进快速安全钻井.本文通过使用砂芯漏斗来模拟页岩的微裂缝,建立了一种新的评价油基钻井液封堵性能的方法,利用该方法对自制的纳米材料CQ-NZC在钻井液封堵性及其与氧化沥青封堵剂的复合作用开展了实验研究.结果表明,CQ-NZC在与沥青类封堵剂复配使用时,能够更好地降低滤失量、提高封堵性能.通过微观形态分析发现,CQ-NZC与沥青类封堵剂可以在一定程度上聚结,形成堵孔粒子,提升了钻井液体系的封堵性能. 相似文献
28.
Reduction of dietary sodium intake by lowering amount of sodium in foods is a global industry target. Quantitative information on current consumer knowledge of sodium reduction trends in Korea is unknown. The objective of this study was to quantify the consumer knowledge and awareness of sodium and salt reduction in foods and to characterize consumer interest in health labeling on the food package. Additionally, comparison of consumer knowledge status between Korea and United States was followed. Consumers (n = 289) participated in an internet survey designed to gauge consumer knowledge and attitudes toward dietary sodium, the sodium content in representative food products (n = 27), and their interest toward specific health claims, including sodium labeling. Questions regarding demographics as well as consumption characteristics were asked. Sodium knowledge index and saltiness belief index were calculated based on the number of correct responses regarding the salt level and sodium content in given food products. Kano analysis was conducted to determine the role of nutrition labels in consumer satisfaction with products. Current consumer knowledge on the sodium content in food products was high, and consumers were adept at matching the sodium content with the salty taste intensity of food products. Consumers’ knowledge of the relationship between diets high in sodium and an increased risk of developing previously reported sodium‐related diseases, such as hypertension, coronary heart disease, kidney disease, and stomach cancer, were also high. Information on the nutrition panel that influences the consumer satisfaction (trans‐fat, sodium, ingredient list, and country of origin) as well as adjective‐nutrition claim pairs that appeal positively to purchase intent of the product were identified. 相似文献
29.
Effect of process variables on product yield distribution in thermal catalytic cracking of naphtha to light olefins over Fe/HZSM-5 总被引:1,自引:0,他引:1
Mina Alyani Jafar Towfighi Seyed Mojtaba Sadrameli 《Korean Journal of Chemical Engineering》2011,28(6):1351-1358
The effect of temperature, WHSV and Fe loading over HZSM-5 catalyst in thermal-catalytic cracking (TCC) of naphtha for the
production of light olefins has been studied. The response surface defined by three most significant parameters is obtained
from Box-Behnken design method and the optimal parameter set is found. The results show that ethylene increases with temperature,
while propylene shows an optimum at 650 °C. Moderate WHSV is favorable for maximum production of light olefins. Addition of
Fe to HZSM-5 has a favorable effect on the production of light olefins up to 6% of loading. Excess amount of loading decreases
the conversion of naphtha, which leads to a drop in light olefin yields. The yield of light olefins (ethylene and propylene)
at 670 °C, 44 hr−1 and 6 wt% Fe has been increased to 5.43 wt% compared to the unmodified HZSM-5 and reaches to 42.47 wt%. 相似文献
30.
Hajimahmoodi Mannan Khanavi Mahnaz Sadeghpour Omid Ardekani Mohammad Reza Shams Mazde Fatemeh Zamani Khoddami Mina Sadat Afzalifard Sheida Ranjbar Ali Mohammad 《Food Analytical Methods》2016,9(12):3451-3459
Food Analytical Methods - Vinegar as a nutraceutical substance is classified to various types related to the different substances applied in production process. Therefore, identity of the source... 相似文献