Browsing by Issue Date, starting with "2014-11-06"

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APPARATUS FOR IDENTIFYING FALLS AND ACTIVITIES OF DAILY LIVING
(2014-11-06)
Yang Bing-Shiang
;
Wang Chih-Chung
;
Liao Sain-Ting
The present invention provides and apparatus for distinguishing falls from activities of daily living (ADLs). First, the human movements and muscle activities would be obtained by an electromyography measuring unit and/or an inertia measuring unit to record ADLs, and falls would be distinguished from ADLs to trigger the protecting devices in time to prevent or decrease injury. In addition, the apparatus would be preset for different operational conditions to adapt different users by a setting unit to increase accuracy. Finally, the moving distance and the direction of the user would be obtained by the electromyography measuring unit and/or the inertia measuring unit to obtain the location thereof in an interior space.
High-performance HfO2/ZrO2/IGZO thin-film transistors deposited using atmospheric pressure plasma jet
(2014-11-06)
Wu, Chien-Hung
;
Chang, Kow-Ming
;
Hsu, Hsin-Yu
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
An atmospheric pressure plasma jet (APPJ) deposition technology that is employed for the preparation of transparent oxide semiconductors film using an eco-friendly water-based metal salt solution as a precursor is presented. Through the use of APPJ indium-gallium-zinc-oxide (IGZO) film as the channel material and a high-k dielectric HfO2/ZrO2 gate stack, IGZO-based transparent thin-film transistors (TFTs) were fabricated and characterised. The HfO2/ZrO2/IGZO-TFTs by APPJ demonstrated excellent electrical characteristics, including a low V-th of 0.63 V, a small subthreshold swing of 0.37 V/dec, a high mobility of 40 cm(2)/V-s and a large I-on/I-off ratio of 7 x 10(8).
Synthesis and Molecular Properties of Tricyclic Biselenophene-Based Derivatives with Nitrogen, Silicon, Germanium, Vinylidene, and Ethylene Bridges
(2014-11-07)
Pao, Yu-Chieh
;
Chen, Yung-Lung
;
Chen, Yen-Ting
;
Cheng, Sheng-Wen
;
Lai, Yu-Ying
A new class of biselenophene-based materials including an sp(3)-silicon-bridged diselenosilole (DSS), an sp(3)-germanium-bridged diselenogermole (DSG), and an sp(3)-nitrogen-bridged diselenopyrrole (DSP) as well as an sp(2)-vinylidene-bridged dicyanodiselenofulvene (CDSF), a diacetylenediselenofulvene (ADSF), and a dioctylethylene-bridged benzodiselenophene (BDS) have been successfully synthesized and characterized. The bridging moieties play an important role in determining the optical and electrochemical properties. The six brominated derivatives are ready to construct various biselenophene-based conjugated materials with tunable properties for organic photovoltaics and field effect transistors.
Synthesis of novel platinum complex core as a selective Ag+ sensor and its H-bonded tetrads self-assembled with triarylamine dendrimers for electron/energy transfers
(2014-11-07)
Shellaiah, Muthaiah
;
Raju, Mandapati V. Ramakrishnam
;
Singh, Ashutosh
;
Lin, Hsin-Chieh
;
Wei, Kung-Hwa
A novel platinum complex PtC with a tri-armed uracil hydrogen-bonded (H-bonded) unit was synthesized via a modular synthetic approach and characterized by H-1, C-13 NMR and MALDI-TOF mass spectroscopies. Two H-bonded tetrads, PtC-(TPAD1)(3) and PtC-(TPAD2)(3), based on a metal core PtC complexed with two generations of triarylamine dendrimers, TPAD1 and TPAD2 (with electron-donating nature), were successfully constructed with improved organic solubility via a classical H-bonded self-assembly approach. Supramolecular H-bonding in solution and solid state was elucidated by H-1 NMR titrations, IR spectral studies and time resolved photoluminescence (TRPL) measurements. The electron/energy transfers, as well as the self-assemblies of supramolecular tetrads, were established by UV-Vis and PL titrations and AFM morphological studies. Furthermore, metal complex core PtC showed selective sensitivity towards Ag+ ions through fluorescence turn-off responses without any interference from other common metal ions. The 1 : 1 binding stoichiometry and complexation mechanism between the probe and Ag+ ion was established by H-1 NMR titration. Moreover, PL reversibility of PtC + Ag+ could be achieved on addition of PMDTA.
A fluorescence turn-on probe for cysteine and homocysteine based on thiol-triggered benzothiazolidine ring formation
(2014-11-07)
Liu, Shi-Rong
;
Chang, Chao-Yiu
;
Wu, Shu-Pao
;
應用化學系
;
Department of Applied Chemistry
We synthesized a new coumarin-based probe TP, containing a disulfide moiety, to detect biothiols in cells. A fluorescence turn-on response is induced by the thiol-disulfide exchange of the probe, with subsequent intramolecular benzothiazolidine ring formation giving rise to a fluorescent product. The probe exhibits an excellent selectivity for cysteine (Cys) and homocysteine (Hcy) over glutathione (GSH) and other amino acids. The fluorescent probe also exhibits a highly sensitive fluorescence turn-on response to Cys and Hcy with detection limits of 0.8 mu M for Cys and 0.5 mu M for Hcy. In addition, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that the probe TP could be an efficient fluorescent detector for thiols in living cells. (C) 2014 Elsevier B.V. All rights reserved.
Multicomponent Reactions of Phosphines, Diynedioates, and Aryl Aldehydes Generated Furans Appending Reactive Phosphorus Ylides through Cumulated Trienoates as Key Intermediates: A Phosphine alpha-Addition-delta-Evolvement of an Anion Pathway
(2014-11-07)
Deng, Jie-Cheng
;
Chuang, Shih-Ching
;
應用化學系
;
Department of Applied Chemistry
Multicomponent reactions of phosphines, diynedioates, and aryl aldehydes have been demonstrated, providing trisubstituted furans appending reactive phosphorus ylides, through cumulated trienoates as key intermediates. The proposed trienoate intermediates, 1,5-dipolar species formed via nucleophilic alpha-attack of phosphines toward diynedioates (alpha-addition-delta-evolvement of an anion, abbreviated alpha A delta E), undergo addition to aryl aldehydes followed by 5-endo-dig cyclization, proton transfer, and resonance to give trisubstituted furans. Furthermore, the phosphorus ylides are oxidized to alpha-keto ester furans and utilized as Wittig reagents.
Dynamic mesoscale model of dipolar fluids via fluctuating hydrodynamics
(2014-11-07)
Persson, Rasmus A. X.
;
Voulgarakis, Nikolaos K.
;
Chu, Jhih-Wei
;
生物科技學系
;
生物資訊及系統生物研究所
Fluctuating hydrodynamics (FHD) is a general framework of mesoscopic modeling and simulation based on conservational laws and constitutive equations of linear and nonlinear responses. However, explicit representation of electrical forces in FHD has yet to appear. In this work, we devised an Ansatz for the dynamics of dipole moment densities that is linked with the Poisson equation of the electrical potential phi in coupling to the other equations of FHD. The resulting phi-FHD equations then serve as a platform for integrating the essential forces, including electrostatics in addition to hydrodynamics, pressure-volume equation of state, surface tension, and solvent-particle interactions that govern the emergent behaviors of molecular systems at an intermediate scale. This unique merit of phi-FHD is illustrated by showing that the water dielectric function and ion hydration free energies in homogeneous and heterogenous systems can be captured accurately via the mesoscopic simulation. Furthermore, we show that the field variables of phi-FHD can be mapped from the trajectory of an all-atom molecular dynamics simulation such that model development and parametrization can be based on the information obtained at a finer-grained scale. With the aforementioned multiscale capabilities and a spatial resolution as high as 5 angstrom, the phi-FHD equations represent a useful semi-explicit solvent model for the modeling and simulation of complex systems, such as biomolecular machines and nanofluidics. (C) 2014 AIP Publishing LLC.
Self-Assembly of Tetraphenylethene-Based [2]Catenane Driven by Acid Base-Controllable Molecular Switching and Its Enabled Aggregation-Induced Emission
(2014-11-07)
Raju, Mandapati V. Ramakrishnam
;
Lin, Hong-Cheu
;
材料科學與工程學系
;
Department of Materials Science and Engineering
A novel [2]catenane 2-C based on the tetraphenylethene (TPE) and orthogonal H-bonded cleft was successfully constructed. VT-NMR and TEM measurements demonstrate that 2-C could be self-assembled to induce an enabled aggregation-induced emission (AIE) in aqueous solution and solid state owing to its TPE unit as well as present unique acid-base controllable and reversible supramolecular self-assembled nanosuperstructures by interplay of a wide range of noncovalent interactions.
Dynamic study on the transformation process of gold nanoclusters
(2014-11-07)
Ma, Xiaoqian
;
Wen, Xiaoming
;
Toh, Yon-Rui
;
Huang, Kuo-Yen
;
Tang, Jau
In this paper, the transformation process from Au-8 to Au-25 nanoclusters (NCs) is investigated with steady state fluorescence spectroscopy and time-resolved fluorescence spectroscopy at various reaction temperatures and solvent diffusivities. Results demonstrate that Au-8 NCs, protected by bovine serum albumin, transform into Au-25 NCs under controlled pH values through an endothermic reaction with the activation energy of 74 kJ mol(-1). Meanwhile, the characteristic s-shaped curves describing the formation of Au-25 NCs suggest this process involves a diffusion controlled growth mechanism.
Deformative Transition of the Menschutkin Reaction and Helical Atropisomers in a Congested Polyheterocyclic System
(2014-11-07)
Chang, Yung-Yu
;
Ho, Tse-Lok
;
Chung, Wen-Sheng
;
應用化學系
;
Department of Applied Chemistry
A 4,7-phenanthroline polycyclic 1A designed for probing the limits of the Menschutkin reaction was synthesized in a six-step sequence. The rotational barrier of the phenyl ring nearby the N-methyl group in rac-2A was estimated to be >= 18.1 kcal/mol from VT-NMR experiments, making them a new type of helical atropisomer. The methylation rate constants of 9 and 1A with MeI was found to be 2.22 x 10 (4) and 9.62 x 10 (6) s(1) mol(1) L, respectively; thus, the formation rate of (P/M)-2A is one of the slowest rates ever reported for a Menschutkin reaction. The N-methyl protons in (P/M)-2A exhibit a significant upfield shift (Delta delta 1.0 ppm) in its H-1 NMR, compared to those without a nearby phenyl, indicating a strong CH-pi interaction is involved. Conformational flexibility in dipyridylethene 9 is clearly shown by its complexation with BH3 to form helical atropisomers (P,P/M,M)-10. The pKa values of the conjugate acids of 1A and 9 in acetonitrile were determined to be 4.65 and 5.07, respectively, which are much smaller compared to that of pyridine 14a (pK(a) = 12.33), implying that the basicity, nucleophilicity, and amine alkylation rates of 1A and 9 are markedly decreased by the severe steric hindrance of the flanking phenyl rings in the polyheterocycles.
Synthesis of novel platinum complex core as a selective Ag+ sensor and its H-bonded tetrads self-assembled with triarylamine dendrimers for electron/energy transfers
(2014-11-07)
Shellaiah, Muthaiah
;
Raju, Mandapati V. Ramakrishnam
;
Singh, Ashutosh
;
Lin, Hsin-Chieh
;
Wei, Kung-Hwa
A novel platinum complex PtC with a tri-armed uracil hydrogen-bonded (H-bonded) unit was synthesized via a modular synthetic approach and characterized by H-1, C-13 NMR and MALDI-TOF mass spectroscopies. Two H-bonded tetrads, PtC-(TPAD1)(3) and PtC-(TPAD2)(3), based on a metal core PtC complexed with two generations of triarylamine dendrimers, TPAD1 and TPAD2 (with electron-donating nature), were successfully constructed with improved organic solubility via a classical H-bonded self-assembly approach. Supramolecular H-bonding in solution and solid state was elucidated by H-1 NMR titrations, IR spectral studies and time resolved photoluminescence (TRPL) measurements. The electron/energy transfers, as well as the self-assemblies of supramolecular tetrads, were established by UV-Vis and PL titrations and AFM morphological studies. Furthermore, metal complex core PtC showed selective sensitivity towards Ag+ ions through fluorescence turn-off responses without any interference from other common metal ions. The 1: 1 binding stoichiometry and complexation mechanism between the probe and Ag+ ion was established by H-1 NMR titration. Moreover, PL reversibility of PtC + Ag+ could be achieved on addition of PMDTA.
光電晶體
(2014-11-11)
冉曉雯
;
孟心飛
;
蔡娟娟
;
陳蔚宗
;
趙宇強
A New Ladder-Type Germanium-Bridged Dithienocarbazole Arene and Its Donor-Acceptor Conjugated Copolymers: Synthesis, Molecular Properties, and photovoltaic Applications
(2014-11-11)
Jwo, Pei-Chi
;
Lai, Yu-Ying
;
Tsai, Che-En
;
Lai, Yun-Yu
;
Liang, Wei-Wei
We have developed a new germanium-bridged heptacyclic arene, dithienogermolocarbazole (DTGC), in which two outer thiophene subunits are covalently fastened to the central 2,7-carbazole core by two dibutylgermanium bridges. The germole moieties embedded in the DTGC structure were successfully constructed by one-pot nucleophilic cyclization in a high yield of 88%. Because of the relatively lower polarity of carbongermanium bonds, the DTGC unit is chemically stable under basic conditions, rendering its more versatile functionalization. Comparison of germanium-bridged DTGC with the carbon-bridged DTCC (dithienocyclopentacarbazole) and silicon-bridged DTSC (dithienosilolocarbazole) analogues reveals that the HOMO energy level of DTGC lies between those of DTCC and DTSC and so does the LUMO energy level of DTGC. Density functional theory (DFT) calculations suggest that DTSC and DTGC have more bent structures than DTCC, which plays an important role in determining their frontier orbital energies. The structural disparity could be amplified in their corresponding polymers. The DTGC unit was copolymerized with four different comonomers, including benzothiadiazole (BT), dithienylbenzothiadiazole (DTBT), difluorobenzothiadiazole (FBT), and dithienyldifluorobenzothiadiazole (DTFBT) to yield a series of new alternating donoracceptor copolymers, poly(dithienogermolo-carbazole-alt-benzothiadiazole) (PDTGCBT), poly(dithienogermolocarbazole-alt-dithienylbenzothiadiazole) (PDTGCDTBT), poly(dithienogermolocarbazole-alt-difluorobenzothiadiazole) (PDTGCFBT), and poly(dithienogermolocarbazole-alt-dithienyldifluorobenzothiadiazole) (PDTGCDTFBT). Because of the two additional thiophene rings in the repeating units on the backbone to facilitate pi-electron delocalization, PDTGCFDTBT showed a lower optical band gap than PDTGCFBT. Furthermore, PDTGCDTFBT also showed the lower-lying LUMO and HOMO energy levels than PDTGCDTBT as a result of the electron-withdrawing fluorine atoms. Consequently, the bulk heterojunction solar cell incorporating PDTGCDTFBT delivered the highest performance with V-oc of 0.84 V, Jsc of 9.87 mA/cm(2), FF of 48.8%, and PCE of 4.05%. By adding 3 vol % 1-chloronaphthalene to tailor the morphology, the solar cell using PDTGCDTFBT with higher molecular weight exhibited the improved efficiency of 4.50% with a V-oc of 0.84 V, a J(sc) of 11.19 mA/cm(2), and an FF of 47.7%.
奈米粒子藥物載體、藥物組合物及其製造方法
(2014-11-11)
陳三元
;
李偉銘
具有空氣介質層之半導體光電元件及空氣介質層之製作方法
(2014-11-11)
盧廷昌
;
黃煇閔
;
郭浩中
;
王興宗
Protein Thermal Stability Enhancement by Designing Salt Bridges: A Combined Computational and Experimental Study
(2014-11-13)
Lee, Chi-Wen
;
Wang, Hsiu-Jung
;
Hwang, Jenn-Kang
;
Tseng, Ching-Ping
;
生物資訊及系統生物研究所
Protein thermal stability is an important factor considered in medical and industrial applications. Many structural characteristics related to protein thermal stability have been elucidated, and increasing salt bridges is considered as one of the most efficient strategies to increase protein thermal stability. However, the accurate simulation of salt bridges remains difficult. In this study, a novel method for salt-bridge design was proposed based on the statistical analysis of 10,556 surface salt bridges on 6,493 X-ray protein structures. These salt bridges were first categorized based on pairing residues, secondary structure locations, and C alpha-C alpha distances. Pairing preferences generalized from statistical analysis were used to construct a salt-bridge pair index and utilized in a weighted electrostatic attraction model to find the effective pairings for designing salt bridges. The model was also coupled with B-factor, weighted contact number, relative solvent accessibility, and conservation prescreening to determine the residues appropriate for the thermal adaptive design of salt bridges. According to our method, eight putative salt-bridges were designed on a mesophilic beta-glucosidase and 24 variants were constructed to verify the predictions. Six putative salt-bridges leaded to the increase of the enzyme thermal stability. A significant increase in melting temperature of 8.8, 4.8, 3.7, 1.3, 1.2, and 0.7 degrees C of the putative salt-bridges N437K-D49, E96R-D28, E96K-D28, S440K-E70, T231K-D388, and Q277E-D282 was detected, respectively. Reversing the polarity of T231K-D388 to T231D-D388K resulted in a further increase in melting temperatures by 3.6 degrees C, which may be caused by the transformation of an intra-subunit electrostatic interaction into an inter-subunit one depending on the local environment. The combination of the thermostable variants (N437K, E96R, T231D and D388K) generated a melting temperature increase of 15.7 degrees C. Thus, this study demonstrated a novel method for the thermal adaptive design of salt bridges through inference of suitable positions and substitutions.
Enhanced thermal radiation in terahertz and far-infrared regime by hot phonon excitation in a field effect transistor
(2014-11-14)
Chung, Pei-Kang
;
Yen, Shun-Tung
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
We demonstrate the hot phonon effect on thermal radiation in the terahertz and far-infrared regime. A pseudomorphic high electron mobility transistor is used for efficiently exciting hot phonons. Boosting the hot phonon population can enhance the efficiency of thermal radiation. The transistor can yield at least a radiation power of 13 mu W and a power conversion efficiency higher than a resistor by more than 20%. (C) 2014 AIP Publishing LLC.
An ultra-efficient energy transfer beyond plasmonic light scattering
(2014-11-14)
Fu, Sze-Ming
;
Zhong, Yan-Kai
;
Lin, Albert
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The energy transfer between nano-particles is of great importance for, solar cells, light-emitting diodes, nano-particle waveguides, and other photonic devices. This study shows through novel design and algorithm optimization, the energy transfer efficiency between plasmonic and dielectric nano-particles can be greatly improved. Using versatile designs including core-shell wrapping, supercells and dielectric mediated plasmonic scattering, 0.05 dB/mu m attenuation can be achieved, which is 20-fold reduction over the baseline plasmonic nano-particle chain, and 8-fold reduction over the baseline dielectric nano-particle chain. In addition, it is also found that the dielectric nanoparticle chains can actually be more efficient than the plasmonic ones, at their respective optimized geometry. The underlying physics is that although plasmonic nano-particles provide stronger coupling and field emission, the effect of plasmonic absorption loss is actually more dominant resulting in high attenuation. Finally, the group velocity for all design schemes proposed in this work is shown to be maintained above 0.4c, and it is found that the geometry optimization for transmission also boosts the group velocity. (C) 2014 AIP Publishing LLC.
CaY2Si2S8:Ce3+: a novel green-emitting thiosilicate phosphor for white light-emitting diodes
(2014-11-14)
Lee, Szu-Ping
;
Huang, Chien-Hao
;
Chen, Teng-Ming
;
應用化學系
;
應用化學系分子科學碩博班
A novel green-emitting Ce3+-doped CaY2Si2S8 thiosilicate phosphor was synthesized by using solid-state methods in a sealed silica ampoule. This compound could be excited over a broad range from UV to blue light (400-450 nm) and generated a broadband emission peaking at similar to 495 nm, with a quantum efficiency of similar to 57%, which is promising for solid-state lighting applications. Temperature-dependent optical measurements of CaY2Si2S8:Ce3+ from 25 to 225 degrees C were performed. In addition, a white LED device was fabricated by using the green-emitting CaY2Si2S8:Ce3+ phosphor and commercially-available red-emitting CaAlSiN3:Eu2+ pumped with a 450 nm blue chip. The CRI value and CCT were measured to be 91-95 and 3800-8600 K, respectively, showing promising potential for solid-state lighting applications. The preparation, spectroscopic characterization, quantum efficiency, decay lifetime, thermal stability, and related LED device data are also presented.
Efficient cooperative access class barring with load balancing and traffic adaptive radio resource management for M2M communications over LTE-A
(2014-11-14)
Hsu, Yi-Huai
;
Wang, Kuochen
;
Tseng, Yu-Chee
;
資訊工程學系
;
Department of Computer Science
We propose two efficient cooperative access class barring with load balancing (CACB-LB) and traffic adaptive radio resource management (TARRM) schemes for M2M communications over LTE-A. The proposed CACB-LB uses the percentage of the number of Machine-Type Communication (MTC) devices that can only access one eNB between two adjacent eNBs as a criterion to allocate those MTC devices that are located in the overlapped coverage area to each eNB. Note that an eNB is a base station of LTE-A. In this way, the proposed CACB-LB can achieve better load balancing among eNBs than CACB, which is the best available related work. The proposed CACB-LB also uses the ratio of the channel quality indication that an MTC device received from an eNB over the number of MTC devices that attach to the eNB as a criterion to adjust the estimated number of MTC devices that may access the eNB. As a result, the proposed CACB-LB can have a better set of barring rates of access class barring than CACB and can reduce random access delay experienced by an MTC device, which is also applicable to user equipment (UE). After an MTC device successfully accesses to an eNB, the eNB needs to allocate radio resources for the MTC device. In addition, the proposed TARRM allocates radio resources for an MTC device based on the random access rate of the MTC device and the amount of data uploaded and downloaded by the MTC device in a homogeneous MTC device network, and the priority of an MTC device in a heterogeneous MTC device network. Furthermore, we use the concept from cognitive radio networks such that if there are unused physical resource blocks (PRBs) of UEs, an eNB can schedule MTC devices to use these PRBs to enhance the throughput performance. Simulation results show that either in a homogeneous MTC device network or in a heterogeneous MTC device network, the proposed CACB-LB\'s average access delay of UEs/MTC devices and average throughput from UEs/MTC devices are better than CACB\'s. The proposed CACB-LB with TARRM\'s average throughput from UEs/MTC devices is also higher than CACB\'s. Therefore, the proposed CACB-LB with TARRM is feasible for M2M communications over LTE-A. (C) 2014 Elsevier B.V. All rights reserved.