Browsing by Author "Huang, Tzu-Ping"

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A Digital-Type GaN Driver with Current-Pulse-Balancer Technique Achieving Sub-Nanosecond Current Pulse Width for High-Resolution and Dynamic Effective Range LiDAR System
(2019-01-01)
Ma, Yu-Sheng
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Lin, Zong-Yi
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Lin, Yen-Ting
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Lee, Cheng-Yen
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Huang, Tzu-Ping
A High Current efficiency Stacked Digital Low Dropout Array with True-Random-Noise Injection and Ultralow Output Ripple for Power-Side Channel Attack Protection
(2019-01-01)
Lee, Cheng-Yen
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Huang, Tzu-Ping
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Chen, Ke-Horng
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Lin, Ying-Hsi
;
Lin, Shian-Ru
This paper proposes a stacked digital low dropout (DLDO) array with three stacked groups to improve security and efficiency, consuming 1/3 of the input current in the prior art. The security is improved by two mechanisms. The advanced encryption standard (AES) engine can be one of point of loads (POLs) hidden in the deeper levels to minimize the disturbance from the AES to the input current. The other is the digital balanced interleave control (DBIC) receives random sources from internal leakage current frequency generator (LCFG) to generate randomly noise current to further hide the current interference caused by the AFS. Due to DBIC anti LCFG techniques, the correlation between input current and AES current is low to 0.006, which is 150 times lower than that of conventional DLDO.
A Right-Half-Plane Zero -Free Buck-Boost DC -DC Converter with 97.46% High Efficiency and Low Output Voltage Ripple
(2019-01-01)
Lin, Yen-An
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Huang, Tzu-Ping
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Ou-Yang, You-Zheng
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Wu, Zheng-Ru
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Chen, Ke-Horng
The right -half-plane (RIIP) zero can he eliminated in the proposed buck-boost (BB) converter to achieve fast transients for Internet-ofThing (IoT) applications. The pseudo-boost mode in the BB converter eliminates one power switch in the current path and ensures that the continuous inductor current is half of the conventional design value to achieve 97.46% peak efficiency. Besides, the output voltage ripple is reduced to 7mV. By inserting an additional phase, a smooth transition between the buck and pseudo -boost modes ensures a voltage drop less than 15mV. The slope-based transient enhancement (SBTE) circuit accelerates transient response in 9 S with a load variation of 400 mA.
Autoionizing Rydberg series (np ', nf ') of Ar investigated by stepwise excitations with lasers and synchrotron radiation
(2008-08-01)
Lee, Yin-Yu
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Dung, Tzan-Yi
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Hsieh, Re-Ming
;
Yuh, Jih-Young
;
Song, Yen-Fang
Synchrotron radiation is used to excite Ar to the intermediate states 3p(1/2)(5) (3d '[3/2](1), 5d '[3/2](1), 5s '[1/2](1,) 7s '[1/2](1)) and 3p(3/2)(5) (6d[1/2](1), 6d[3/2](1), 8s[3/2](1)), then excited by lasers to the autoionizing Rydberg series 3p(1/2)(5) np ' ([1/2](0,1), [3/2](1,2)) and nf '[5/2](2). For the intermediate states of 5s ', 7s ', and 8s, the np ' ([1/2](0) and [3/2](2)) series are observed with high intensity but not the np ' ([1/2](1) and [3/2](1)) series when the polarization vectors of two light beams are in parallel; but when they are in orthogonal, the np '[1/2](0) series disappears, the np '[3/2](2) intensity remains, and the np ' ([1/2](1) and [3/2](1)) series show up strongly. The intensity distribution of the np ' series strongly depends on the intermediate state. The spectra of the np ' series are assigned according to their intensity variation with the polarization vectors. The quantum defects determined for the series np '[1/2](0)(n=11-57), np '[312](2)(n=11-65), np '[3/2](1)(n=11-31), and nf '[5/2](2)(n=9-74) are 1.611 +/- 0.011, 1.683 +/- 0.013, 1.688 +/- 0.010, and 0.016 +/- 0.005, respectively. Our values are in excellent agreement with theoretical prediction. The spectral line shapes of autoionizing Rydberg states are analyzed with a Beutler-Fano profile. Reduced autoionization linewidths for the np '[1/2](0)(n= 11-16) series vary in the range 2549-4145 cm(-1), and the nf '[5/2](2)(n=9-11) series in 186-247 cm(-1) in reasonable agreement with theoretical prediction.
Direct infrared observation of hydrogen chloride anions in solid argon
(2017-09-21)
Huang, Tzu-Ping
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Chen, Hui-Fen
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Liu, Meng-Chen
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Chin, Chih-Hao
;
Durrant, Marcus C.
To facilitate direct spectroscopic observation of hydrogen chloride anions (HCl-), electron bombardment of CH3Cl diluted in excess Ar during matrix deposition was used to generate this anion. Subsequent characterization were performed by IR spectroscopy and quantum chemical calculations. Moreover the band intensity of HCl fi decays slowly when the matrix sample is maintained in the dark for a prolonged time. High-level ab inito calculation suggested that HCl fi is only weakly bound. Atom-in-molecule charge analysis indicated that both atoms of HCl fi are negatively charged and the Cl atom is hypervalent. Published by AIP Publishing.
Direct IR Absorption Spectra of Propargyl Cation Isolated in Solid Argon
(2018-09-26)
Chin, Chih-Hao
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Lin, Meng-Yeh
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Huang, Tzu-Ping
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Wu, Pei-Zhen
;
Wu, Yu-Jong
The direct infrared (IR) absorption spectra of propargyl cations were recorded. These cations were generated via the electron bombardment of a propyne/Ar matrix sample during matrix deposition. Secondary photolysis with selected ultraviolet (UV) light was used for grouping the observed bands of various products. The band assignment of the propargyl cation in solid Ar was performed according by referring to the previous infrared photodissociation (IRPD) and velocity-map imaging photoelectron (VMI-PE) data, and via theoretical predictions of the anharmonic vibrational wavenumbers, band intensities, and deuterium-substituted isotopic ratios. Almost all the IR active bands with an observable intensity were recorded and the nu(11) mode was reported for the first time.
Formation and identification of borane radical anions isolated in solid argon
(2018-02-21)
Lin, Meng-Yeh
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Huang, Tzu-Ping
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Chin, Chih-Hao
;
Wu, Yu-Jong
;
應用化學系
The infrared (IR) spectrum of borane(3) anions (BH3-) isolated in solid Ar was recorded; two vibrational modes were observed at 2259.4 and 606.6 cm(-1), which were assigned to the BH2 stretching (nu(3)) and out-of-plane large-amplitude (nu(2)) modes, respectively. These anions were produced by the electron bombardment of an Ar matrix sample containing a small proportion of B2H6 and H-2 during matrix deposition or by the photolysis of single-bridged-B2H5 fi in an Ar matrix with the selected ultraviolet light. The band positions, relative intensity ratios, isotopic splitting pattern, and isotopic shift ratios of the observed IR features of BH3- are generally in good agreement with those predicted by the B2PLYP/aug-cc-pVTZ method.
Formation and IR spectrum of monobridged Si2H4 isolated in solid argon
(2020-05-29)
Lin, Shu-Yu
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Chou, Sheng-Lung
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Lin, Meng-Yeh
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Huang, Wen-Jian
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Huang, Tzu-Ping
The infrared (IR) spectrum of monobridged Si2H4 (denoted as mbr-Si2H4) isolated in solid Ar was recorded, and a set of lines (in the major matrix site) observed at 858.3 cm(-1), 971.5 cm(-1), 999.2 cm(-1), 1572.7 cm(-1), 2017.7 cm(-1), 2150.4 cm(-1), and 2158.4 cm(-1) were characterized. The species was produced by the electron bombardment of an Ar matrix sample containing a small proportion of SiH4 during matrix deposition. Upon photolysis of the matrix samples using 365 nm and 160 nm light, the content of mbr-Si2H4 increased. The band positions, relative intensity ratios, and D-isotopic shift ratios of the observed IR features are generally in good agreement with those predicted by the B3LYP/aug-cc-pVTZ method. In addition, the photochemistry of the observed products was discussed.
Formation of Halogen-bearing Species. I. Irradiation of Methyl Fluorides in Carbon Monoxide Ice with VUV Light and Electrons
(2019-08-01)
Lin, Meng-Yeh
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Huang, Tzu-Ping
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Wu, Pei-Zhen
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Chin, Chih-Hao
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Wu, Yu-Jong
We studied the synthesis of fluorine-bearing species by the irradiation of CO ice containing a small proportion of CH3F at 10 K with vacuum ultraviolet (VUV) light and energetic electrons. Photolysis of the ice sample with VUV light with a wavelength of 121.6 nm produced mainly fragments of CH3F, whereas both carbon oxides and fragments of CH3F were generated by irradiation with broadband VUV light. In contrast, electron irradiation of a similar ice sample generated not only those products observed in the photolysis experiments, but also complex organic hydrocarbons and fluorinated (carbon) oxides. This observation of the distinctive effect of the formation of different products by different excitation sources provides an insight into the energetic processes occurring in interstellar icy dust grains.
Formation of Halogen-bearing Species. II. Irradiation of Chloromethane in Carbon Monoxide Ice with VUV Light and Electrons
(2020-01-01)
Lin, Meng-Yeh
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Huang, Tzu-Ping
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Wu, Pei-Zhen
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Chin, Chih-Hao
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Wu, Yu-Jong
The synthesis of chlorine-bearing species in CO ice was studied by the irradiation of CH3Cl:CO ice at 10 K with vacuum-ultraviolet (VUV) light and energetic electrons. In contrast to the photochemical behavior of CH3F:CO ice, photolysis of CH3Cl:CO ice with Ly alpha or broadband VUV light afforded various products. This discrepancy was attributed to the abundant absorption bands of CH3Cl in the VUV region, particularly in the Ly alpha region. The Cl-bearing species including Cl2O, ClCO, C3Cl2, C3HCl, and HOOCl were characterized by observing their IR features. In contrast, electron bombardment of ice mixtures produced various carbon oxides and primary products, such as CH2Cl and HCO. In addition, the mechanism of energetic processes in electron bombardment was discussed.
Identification of a Simplest Hypervalent Hydrogen Fluoride Anion in Solid Argon
(2017-06-07)
Liu, Meng-Chen
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Chen, Hui-Fen
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Chin, Chih-Hao
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Huang, Tzu-Ping
;
Chen, Yu-Jung
Hypervalent molecules are one of the exceptions to the octet rule. Bonding in most hypervalent molecules is well rationalized by the Rundle-Pimentel model (three-center four-electron bond), and high ionic bonding between the ligands and the central atom is essential for stabilizing hypervalent molecules. Here, we produced one of the simplest hypervalent anions, HF-, which is known to deviate from the Rundle-Pimentel model, and identified its ro-vibrational features. High-level ab inito calculations reveal that its bond dissociation energy is comparable to that of dihalides, as supported by secondary photolysis experiments with irradiation at various wavelengths. The charge distribution analysis suggested that the F atom of HF-is negative and hypervalent and the bonding is more covalent than ionic.
INFRARED AND ULTRAVIOLET SPECTRA OF METHANE DILUTED IN SOLID NITROGEN AND IRRADIATED WITH ELECTRONS DURING DEPOSITION AT VARIOUS TEMPERATURES
(2016-06-01)
Chin, Chih-Hao
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Chen, Sian-Cong
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Liu, Meng-Chen
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Huang, Tzu-Ping
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Wu, Yu-Jong
We recorded the infrared and ultraviolet absorption spectra of CH4:N-2 matrix samples that underwent electron bombardment during deposition in the temperature range of 10-44 K. In contrast to a previous experiment on the IR spectroscopy of electron-bombarded icy samples, methyl and azide radicals became the main products upon electron bombardment during deposition; furthermore, reduced production of nitrile species was observed for deposition at 10 and 20 K. On the other hand, for deposition above 33 K, the observed bands of the radical species (such as methyl and azide) decreased, and bands of large nitriles appeared. This observation may suggest that radical species easily diffuse and recombine to form more complex molecules in solid nitrogen at higher temperatures. Further measurements of similar samples at 10-33 K in the UV region revealed the intense band of azide radicals at 272.5 nm and weak, broad, overlapping features of methyl and azide radicals in the 225-197 nm region. For deposition at 44 K, only a broad feature centered at 219.4 nm was observed, and the possible carriers of nitrile species were proposed based on the corresponding IR spectrum and theoretical predictions of excitation energy. This band is similar to the observed absorption feature of Pluto's surface recorded by the Hubble telescope in terms of both band position and bandwidth. Our findings therefore further support the suggestion that complex nitrile species may exist on the surface of Pluto.
Infrared spectra of isotopomers of chloromethylene in solid argon
(2018-03-01)
Lin, Meng-Yeh
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Huang, Tzu-Ping
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Chin, Chih-Hao
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Lee, Yin-Yu
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Wu, Yu-Jong
We measured the IR spectra of the solid Ar-trapped chloromethylene (HCCl) prepared by electron bombardment of a CH3Cl/Ar mixture during matrix deposition. Irradiation of matrix samples at 210 nm decreased the intensity of lines corresponding to HCCl, whereas irradiation at 385 nm had an opposite effect. The above behavior allowed an unambiguous identification of all vibrational modes of HCCl, and the obtained assignments were further confirmed by quantum chemical calculations and C-13/H-2 isotopic labeling experiments. (C) 2017 Elsevier Inc. All rights reserved.
Infrared Spectra of the 1-Methylvinoxide Radical and Anion Isolated in Solid Argon
(2019-06-06)
Lin, Meng-Yeh
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Huang, Tzu-Ping
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Wu, Pei-Zhen
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Chin, Chih-Hao
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Wu, Yu-Jong
The 1-methylvinoxy radical (1-MVO) is an important intermediate in the combustion and tropospheric reaction of OH. However, the vibrational structures of this species and its anionic form, 1-methylvinoxide anion (1-MVO-), are not fully known. Thus, in this study, we obtained the infrared (IR) absorption spectra of 1-MVO and 1-MVO- trapped in a solid Ar matrix. 1-MVO- anions were produced by electron bombardment during matrix deposition of Ar containing a small amount of acetone. The anions were destroyed upon irradiation at 675, 365, and 160 nm, although the formation of 1-MVO was only observed upon irradiation at 675 nm. The assignment of the IR bands of 1-MVO- and 1-MVO was based on the expected chemistry upon photoexcitation and comparison of line wavenumbers, relative IR intensities, and D-isotopic shift ratios with those predicted at the B3LYP/aug-cc-pVTZ level of theory.
Photochemistry and infrared spectrum of single-bridged diborane(5) anion isolated in solid argon
(2016-08-21)
Liu, Meng-Chen
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Chen, Hui-Fen
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Huang, Wei-Jie
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Chin, Chih-Hao
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Chen, Sian-Cong
Three-center two-electron bonds are important for understanding electron-deficient molecules. To examine such a molecule, we produced a diborane(5) anion with a single-bridged structure upon electron bombardment during matrix deposition of Ar containing a small proportion of diborane(6). The diborane(5) anion was destroyed upon photolysis at 180, 220, 385, and 450 nm, but not at 532 nm. Moreover, the possible formation of neutral diborane(5) was observed upon photolysis at 385 and 450 nm, whereas neutral diborane(3) was observed upon photolysis at 180 and 220 nm. The observed line wavenumbers, relative intensities, and isotopic ratios of the diborane(5) anion agreed satisfactorily with those predicted by density functional theory calculations at the B3LYP/aug-cc-pVTZ level of theory. Thus, this method produced the boron hydride anion of interest with few other fragments, which enabled us to clearly identify the IR spectrum of the diborane(5) anion. Published by AIP Publishing.
SrTiO3/TiO2 Hybridstructure as Photoanode in Dye-Sensitized Solar Cell
(2013-12-01)
Wang, Yu-Shiuan
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Chen, Ting-Ting
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Huang, Yi-Jen
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Huang, Tzu-Ping
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Lee, Yin-Yu
In dye-sensitized solar cells (DSSCs), the charge recombination at the TiO2/dye/electrolyte interface greatly influences the photoelectron conversion efficiency. Hybrid semiconductor materials with matched band potentials are designed to reduce the charge recombination. In this study, SrTiO3/TiO2 hybridstructure was synthesized by using TiO2 nanoparticles as template in a hydrothermal, showing a negative shift in the flat band potential. The DSSC with the SrTiO3/TiO2 anode exhibits an increased photovoltage and a reduced photocurrent. The suppression of charge recombination at the TiO2/dye/electrolyte interface was observed in the electrochemical impedance spectroscopy, causing an improvement in the photovoltage. However, the SrTiO3/TiO2 system shows an obstructed electrons injection from the dye to SrTiO3/TiO2, limiting the photocurrent performance. The photoelectrochemical properties of the SrTiO3/TiO2 system are discussed in detail herein.
UV absorption spectrum of allene radical cations in solid argon
(2018-05-05)
Chin, Chih-Hao
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Lin, Meng-Yeh
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Huang, Tzu-Ping
;
Wu, Yu-Jong
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應用化學系
Electron bombardment during deposition of an Ar matrix containing a small proportion of allene generated allene cations. Further irradiation of the matrix sample at 385 nm destroyed the allene cations and formed propyne cations in solid Ar. Both cations were identified according to previously reported IR absorption bands. Using a similar technique, we recorded the ultraviolet absorption spectrum of allene cations in solid Ar. The vibrationally resolved progression recorded in the range of 266-237 nm with intervals of about 800 cm(-1) was assigned to the A E-2 <- X E-2 transition of allene cations, and the broad continuum absorption recorded in the region of 229-214 nm was assigned to their B (2)A(1) <- X E-2 transition. These assignments were made based on the observed photolytic behavior of the progressions and the vertical excitation energies and oscillator strengths calculated using time-dependent density functional theory. (C) 2018 Elsevier B.V. All rights reserved.
Vacuum ultraviolet photolysis of CH4:O-2 ice mixtures and the formation of CO and CO2
(2020-06-05)
Chou, Sheng-Lung
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Lin, Meng-Yeh
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Huang, Tzu-Ping
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Wu, Yu-Jong
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應用化學系
Vacuum ultraviolet (VUV) photolysis of CH4:O-2 ice mixtures at 10 K using 121.6, 157, and 170-nm wavelengths was performed to examine photochemical reactions for the oxidation of hydrocarbon species. Ice samples with three component ratios were prepared: CH4-dominated (CH4:O-2 = 100:1), mixed (CH4:O-2 = 1:1), and O-2-dominated (CH4:O-2 = 1:100) ice samples. Photochemical behavior with dependence on the photolysis wavelength and component ratio was observed. In addition, the column densities of CO and CO2 formed by the VUV photolysis of the three ice samples and the abundance ratios of CO and CO2 as a function of the photon dosage and photolysis wavelength were examined. The results may imply a correlation between the unknown depletion of interstellar oxygen and the formation of CO and CO2. (C) 2020 Elsevier B.V. All rights reserved.