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201.
202.
Electric Field‐Aided Formation Combined with a Nanoimprinting Technique for Replicating a Plant Leaf
The surface of the taro plant leaf was replicated using a nanoimprinting technique (NIT) supplemented with an electric field. This field‐aided nanoimprinting method (FA‐NIT) consists of two steps: applying an electric field to a liquid polymer under the plant leaves and the curing process of the polymer with the applied electric field. An appropriate electric field was needed to induce the electrokinetic phenomena of a liquid polymer to obtain a good replicated surface. The roughness fabricated by the FA‐NIT was about 45% higher than the one prepared by NIT. The FA‐NIT method is a good supplementary technique to improve the quality of NIT.
203.
Nanoscale laser processing and diagnostics 总被引:2,自引:0,他引:2
David Hwang Sang-Gil Ryu Nipun Misra Hojeong Jeon Costas P. Grigoropoulos 《Applied Physics A: Materials Science & Processing》2009,96(2):289-306
The article summarizes research activities of the Laser Thermal Laboratory on pulsed nanosecond and femtosecond laser-based
processing of materials and diagnostics at the nanoscale using optical-near-field processing. Both apertureless and apertured
near-field probes can deliver highly confined irradiation at sufficiently high intensities to impart morphological and structural
changes in materials at the nanometric level. Processing examples include nanoscale selective subtractive (ablation), additive
(chemical vapor deposition), crystallization, and electric, magnetic activation. In the context of nanoscale diagnostics,
optical-near-field-ablation-induced plasma emission was utilized for chemical species analysis by laser-induced breakdown
spectroscopy. Furthermore, optical-near-field irradiation greatly improved sensitivity and reliability of electrical conductance
atomic force microscopy enabling characterization of electron tunneling through the oxide shell on silicon nanowires. Efficient
in-situ monitoring greatly benefits optical-near-field processing. Due to close proximity of the probe tip with respect to
the sample under processing, frequent degradation of the probe end occurs leading to unstable processing conditions. Optical-fiber-based
probes have been coupled to a dual-beam (scanning electron microscopy and focused ion beam) system in order to achieve in-situ
monitoring and probe repair. 相似文献
204.
David J. Hwang Moosung Kim Kuniaki Hiromatsu Hojeong Jeon Costas P. Grigoropoulos 《Applied Physics A: Materials Science & Processing》2009,96(2):385-390
Three-dimensional flow-through microchannels were fabricated inside bulk fused silica glass via ultrashort pulsed laser direct
writing. The device fabrication sequence takes advantage of the nonlinear volumetric absorption in glass and the subsequent
preferential chemical etching process. Optical waveguides were also written into the glass specimen and integrated with the
fluidic conduits. Flow tests using both fluorescent particles and red blood cells (RBCs) were conducted on various three-dimensional
channel configurations. Experiments showed the possibility for laser-induced cell processing inside the microchannels. To
evaluate cytometer functionality, RBCs were detected inside the manufactured microchannel via both transmission and fluorescence
probing. 相似文献
205.
Ji Yeon Choi Ji-Eun Bae Joon Bum Kim Doo Sin Jo Na Yeon Park Yong Hwan Kim Ha Jung Lee Seong Hyun Kim So Hyun Kim Hong Bae Jeon Hye-Won Na Hyungjung Choi Hong-Yeoul Ryu Zae Young Ryoo Hyun-Shik Lee Dong-Hyung Cho 《Molecules (Basel, Switzerland)》2021,26(17)
Primary cilia mediate the interactions between cells and external stresses. Thus, dysregulation of primary cilia is implicated in various ciliopathies, e.g., degeneration of the retina caused by dysregulation of the photoreceptor primary cilium. Particulate matter (PM) can cause epithelium injury and endothelial dysfunction by increasing oxidative stress and inflammatory responses. Previously, we showed that PM disrupts the formation of primary cilia in retinal pigment epithelium (RPE) cells. In the present study, we identified 2-isopropylmalic acid (2-IPMA) as a novel inducer of primary ciliogenesis from a metabolite library screening. Both ciliated cells and primary cilium length were increased in 2-IPMA-treated RPE cells. Notably, 2-IPMA strongly promoted primary ciliogenesis and restored PM2.5-induced dysgenesis of primary cilia in RPE cells. Both excessive reactive oxygen species (ROS) generation and activation of a stress kinase, JNK, by PM2.5 were reduced by 2-IPMA. Moreover, 2-IPMA inhibited proinflammatory cytokine production, i.e., IL-6 and TNF-α, induced by PM2.5 in RPE cells. Taken together, our data suggest that 2-IPMA ameliorates PM2.5-induced inflammation by promoting primary ciliogenesis in RPE cells. 相似文献
206.
207.
Hyunbok Lee Jeihyun Lee Pyungeun Jeon Kwangho Jeong Yeonjin Yi Tae Gun Kim Jeong Won Kim Jin Woo Lee 《Organic Electronics》2012,13(5):820-825
Highly enhanced electron injection is demonstrated with a thin manganese dioxide (MnO2) electron injection layer (EIL) in Alq3-based organic light-emitting diodes. Insertion of the MnO2 EIL between the Al cathode and Alq3 results in highly improved device characteristics. In situ photoelectron spectroscopy shows remarkable reduction of the electron injection barrier without significant chemical reactions between Alq3 and MnO2, which could induce Alq3 destruction. The reduction of the electron injection barrier is due to the n-type doping effect, and the lack of strong interfacial reaction is advantageous with regards to more efficient electron injection than a conventional LiF EIL. These properties render the MnO2, a potential EIL. 相似文献
208.
The complex-number multiplier is one of the key arithmetic components for the baseband signal processing of modern digital communication systems such as channel equalization, timing recovery, modulation and demodulation. This paper presents two algorithms suitable for a high-speed complex-number multiplier, which are based on redundant binary (RB) representation of partial products. The basic idea behind our approach is to convert a pair of binary partial products into a RB form so that the post-addition/subtraction which is inevitable in the conventional methods based on binary multiplication, is eliminated. With the proposed algorithms, the complex-number multiplication is reduced to two RB multiplications, one for the real part and the other for the imaginary part. The RB multiplication is defined by an addition of RB partial products, and is performed in parallel without carry propagation from the least-significant digit to the most-significant digit. This work results not only in simplified arithmetic operations, but also in highly parallel and simple architecture when compared with conventional methods using binary multiplications. To demonstrate the algorithms, two test chips have been implemented using a 0.8µm CMOS technology. 相似文献
209.
Lee D Kwon D Ko W Joo J Seo H Lee SS Jeon S 《Chemical communications (Cambridge, England)》2012,48(57):7182-7184
A rapid and facile signal enhancement method for detecting alpha-fetoprotein (AFP) was developed using the magnetic agglomeration of ferromagnetic nanoparticles and microcantilever sensors. The resonance frequency and deflection of the cantilevers were found to be more than 10-fold greater than that before physical agglomeration of the free nanoparticles around the magnetized nanoparticles. 相似文献
210.
Sunbum Kwon Kyungtae Kang Aram Jeon Ji Hun Park Insung S. Choi Hee-Seung Lee 《Tetrahedron》2012,68(23):4368-4373
In this paper, we report the self-assembly phenomenon of trans-2-aminocyclopentanecarboxylic acid hexamer (ACPC6) by the evaporation-induced self-assembly. The SEM and TEM analyses of the self-assembled 3D molecular architecture revealed the characteristic shape of hollow parallelepiped and its supramolecular chiral expression on surface. A systematic study with the derivatives of ACPC6 showed the effect of the terminal groups of ACPC6 on the particular 3D shape formation. We also found that water molecules played a crucial role in the formation of hollow morphogenesis under the evaporation-induced self-assembly condition, and a plausible formation mechanism was suggested. 相似文献