• 제목/요약/키워드: Transferred Charge

검색결과 97건 처리시간 0.031초

Artificial Photosynthesis Using Zeolites

  • Castagnola, Norma B.;Dutta, Prabir K.
    • Journal of Photoscience
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    • 제6권3호
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    • pp.91-96
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    • 1999
  • Zeolites and microporouos materials continue to attract attention as novel hosts for photochemical reactions. Zeolities are attractive because of their ability to selectivity exchange and incorporate species within the void spaces and interconnecting channels, providing a spatial arrangement of molecules. Our research has primarily focused on intrazeolitic electron transfer from excited Ru(bpy)32+ in supercages of zeolite Y to a series of bipyridinium ions. In the Ru(bpy)32+ viologen-zeolite Y samples, the slowing of the back electron transfer from the bipyridinium radical cation to Ru(bpy)32+ allows for charge propagation via self exchange between diquat molecules. This provides an opportunity for permanent charge separation. When the migrating charge on the diquat radical within the zeolite reaches the surface, it can be transferred to a neutral viologen (PVS) in solution, resulting in permanent charge separation. The advantage of long-lived charge separation can be exploited for useful chemistry if suitable catablysts can be assembled on the zeolities. We have studied Ru(bpy)2 as water oxdiation catalysts. We have demonstrated that synthesis of RuO2 fibers on a zeolite via thermal decomposition of Ru3(CO)12 leads to the most active water decomposition catalyst reported to date. Because of the extensive interest of photochemical water reduction to H2, much is known about catalytic systems usin gone electron catalyst, and even more importantly, that no reaction of viologen occurred with H2 over this catalyst. The present challenge is to incorporate all these elements of the system into an architecture and we are examining zeolite membranes for this purpose.

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$CaSiN_2$를 모체로 하는 형광체의 개발 및 발광 특성 (Development and Luminescent Characteristics of $CaSiN_2$ Based Phosphors)

  • 이순석;임성규
    • 전자공학회논문지D
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    • 제36D권10호
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    • pp.31-36
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    • 1999
  • 질소 화합물의 새로운 형광체를 개발하기 위하여 $CaSiN_2:Eu,\;CaSiN_2:Tb$ 형광체를 합성한 후, 빛 발광 (photoluminescence, PL) 및 전계 발광(electroluminescence, EL) 특성을 평가하였다. $Ca_3N_2$, $Si_3N_4$$EuF_3$ 또는 $TbF_3$의 미분말을 혼합, 성형 및 소결하여 질소 화합물 형광체를 합성하였다. 합성된 $CaSiN_2:Eu,\;CaSiN_2:Tb$ 형광체의 PL 특성이 각각 Eu, Tb 이온에 의한 고유한 발광 파장과 일치하여 형광체로의 활용 가능성을 확인하였다. 스퍼터링 방법으로 제작된 $CaSiN_2:Eu$ 박막 전계 발광(thin-film electroluminescence, TFEL) 소자의 문턱 전압과 280 V에서의 발광 휘도는 각각 90 V, 1.62 $cd/m^2$ 임을 알 수 있었다. 또한 change-voltage(Q-V) 및 transferred charge-phosphor Field($Q_t-F_p$)의 전기적 특성도 함께 측정되었다.

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리튬이온 배터리 모듈을 위한 단일셀간 고속 밸런싱 회로 (A Cell-to-Cell Fast Balancing Circuit for Lithium-Ion Battery Module)

  • 팜반롱;간 압둘바싯;응웬탄둥;최우진
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2015년도 추계학술대회 논문집
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    • pp.7-8
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    • 2015
  • In this paper a cell-to-cell fast charge balancing circuit for the Lithium-Ion battery module is proposed. In the proposed topology the energy in a high voltage cell is transferred directly to a low voltage cell through the operation of the dc-dc converter. Furthermore, the charge balancing can be performed regardless of the battery operation whether it is being charged, discharged or relaxed. The monitoring circuit composed of a DSP and a battery monitoring IC is designed to monitor the cell voltage and detect the inferior cell thereby protecting the battery module from failure. In order to demonstrate the performance of the proposed topology, a prototype circuit was designed and applied to 12 Lithium-Ion battery module. It has been verified with the experiments that the charge equalization time of the proposed method was shorter compared with those of other methods.

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Ultra-Clean Patterned Transfer of Single-Layer Graphene by Recyclable Pressure Sensitive Adhesive Films

  • Kim, Sang Jin;Lee, Bora;Choi, Yong Seok;Kim, Philip;Hone, James;Hong, Byung Hee;Bae, Sukang
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.301.1-301.1
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    • 2016
  • We report an ultraclean, cost-effective, and easily scalable method of transferring and patterning large-area graphene using pressure sensitive adhesive films (PSAFs) at room temperature. This simple transfer is enabled by the difference in wettability and adhesion energy of graphene with respect to PSAF and a target substrate. The PSAF transferred graphene is found to be free from residues, and shows excellent charge carrier mobility as high as ${\sim}17,700cm^2/V{\cdot}s$ with less doping compared to the graphene transferred by thermal release tape (TRT) or poly(methyl methacrylate) (PMMA) as well as good uniformity over large areas. In addition, the sheet resistance of graphene transferred by recycled PSAF does not change considerably up to 4 times, which would be advantageous for more cost-effective and environmentally friendly production of large-area graphene films for practical applications.

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Blast resistance of a ceramic-metal armour subjected to air explosion: A parametric study

  • Rezaei, Mohammad Javad;Gerdooei, Mahdi;Nosrati, Hasan Ghaforian
    • Structural Engineering and Mechanics
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    • 제74권6호
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    • pp.737-745
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    • 2020
  • Nowadays, composite plates are widely used as high-strength structures to fabricate a dynamic loading-resistant armours. In this study, the shock load is applied by an explosion of spherical TNT charge at a specified distance from the circular composite plate. The composite plate contains a two-layer ceramic-metal armour and a poly-methyl methacrylate (PMMA) target layer. The dynamic behavior of the composite armour has been investigated by measuring the transferred effective stress and maximum deflection into the target layer. For this purpose, the simulation of the blast loading upon the composite structure was performed by using the load-blast enhanced (LBE) procedure in Ls-Dyna software. The effect of main process parameters such as the thickness of layers, and scaled distance has been examined on the specific stiffness of the structure using response surface method. After validating the results by comparing with the experimental results, the optimal values for these parameters along with the regression equations for transferred effective stress and displacement to the target have been obtained. Finally, the optimal values of input parameters have been specified to achieve minimum transferred stress and displacement, simultaneously with reducing the weight of the structure.

유기전하 이동착물 Langmuir-Blodgett막의 누적조건 및 누적확인에 관한 연구 (Deposition condition and Confirmation of Organic Charge Transfer complex Langmuir-Blodgett Film)

  • 정순욱
    • 한국응용과학기술학회지
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    • 제14권1호
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    • pp.89-93
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    • 1997
  • In this research, ultra-thin films of organic charge transfer complex were deposited on to ordinary microscope slide-glass subtrates with a Langmuir-Blodgett technique. ${\pi}$-A isotherm characteristics of these complex were studied in order to find optimum conditions of deposition by varying temperature of subphase, compression speed, and spreading amount. Transfer ratio of these films were studied during the process of deposition. The UV-visible absorbance spectra of LB films were measured to find state of deposition by varing layer number. The observed optimum conditions of surface, pressure, spreading amount, and dipping speed for depositing LB films(Y-type) were 38m/Nm, $150{\mu}l$ and 5mm/min, respectively. Since the tansfer ratio is close to 100%, the monolayer on the subphase seems to be well transferred to the solid substrate. The thickness of the film was well-controlled as the UV-vis absorbance of films were changed linear according to the number of layers.

An Intramolecular Photosubstitution Reaction of N-(2,4-Dibromonaphthyl)- arenecarboxamide: Synthesis of 2-Arylnaphthoxazole

  • Bae, In-Soo;Kim, Yoo-Shin;Park, Yong-Tae
    • Bulletin of the Korean Chemical Society
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    • 제24권7호
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    • pp.916-920
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    • 2003
  • Photoreactions of N-(2,4-dibromonaphthyl)arenecarboxamides in basic medium result in the intramolecular substituted products, 2-aryl-8-bromonaphthoxazoles in moderate yields and further photoreactions of the products afford the reduced products, 2-arylnaphthoxazoles. These reactions are straightforward for syntheses of naphthoxazole derivatives. Since the intramolecular photosubstitution of the bromoarenecarboxamide by the oxygen of its amide group is more effective than the photoreduction of the substituted product, 2-aryl-8- bromonaphthoxazole in basic medium, the intramolecular substituted product, 2-aryl-8-bromonaphthoxazole can be isolated. A charge-transfered excited singlet state of an imidol form of the 2-bromoarenecarboxamide is involved in the photosubstitution, whereas an excited triplet state of the 2-aryl-8-bromonaphthoxzole is closely involved in the photoreduction.

ZnS:Cu를 이용한 후막 전계발광소자의 고휘도 특성 (High brightness property of Power Electroluminescent Device using ZnS:Cu)

  • 이종찬;박대희
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권5호
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    • pp.349-353
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    • 1999
  • In this paper, to fabricate the AC power electroluminescent device (PELD) with high brightness, new structure that constructed single emissive layer between electrodes was proposed. Dielectric and phosphor material structure that constructed single emissive layer between electrodes was proposed. Dielectric and phosphor material were BaTiO3 and ZnS:Cu respectively. Fabricated AC power EL devices were estimated by optical and electrical properties of EL spectrum, brightness, CIE coordinate system, transferred charge density and EL emission wave in time domain. With above results, we found that brightness of newly proposed AC powder EL power EL device was 2754 cd/m2 at 100V, 400 Hz and compared with conventional device structure.

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자침시(刺鍼時) 압침(押鍼)의 수기자극(手技刺戟)이 전위변화(電位變化)에 미치는 영향(影響) (A Study on the changes of electric charge induced by Apchim (押鍼) manipulation during acupuncture therapy)

  • 송문영;심원보;김영태;백대봉;안성훈;김경식;손인철
    • Korean Journal of Acupuncture
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    • 제22권4호
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    • pp.9-27
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    • 2005
  • Objective : hypothesis. First of all, there exists electric property in meridian and meridian point. Second of all, energy flowing in meridian is related with electric property. Third of all, there is electronic interaction between the operator who performs acupuncture therapy and the receiver who is given acupuncture therapy. Forth of all, acupuncture effects may depend on the electric capacity which is transferred between the operator and the receiver via acupuncture needle. Methods : Under the hypothesis, I studied the effects of electric charge in ST37(+) and ST39(-) generated by Apchim (押鍼) manipulation which was stimulated at ST36 point. And compared with data on the changes of electric charge from the hand of the operator during acupuncture stimulation. Electric charge induced via acupuncture needle from the operator may be important factor that causes the changes of electric charge in meridian and acupoint in the receiver. Therefore we investigated the changes of electric charge induced by the operator using Maclab 400 by the following methods. The one was in stable electric circle condition and the other was in unstable electric circle condition. In this experiments, the changes of electric charge from the stimulation type of Apchim manipulation performed in our lab condition in acupuncture therapy was induced at least three factor, one was the difference of bio-potentials between the operator and the receiver of acupuncture therapy, another was the depth of acupuncture insertion from the skin of the receiver the other was an electromyogram of the receiver. Results :The data imply that the first factor should make a capacitance current when the operator touched the acupuncture needle which was inserted in the receiver. Therefore, the results suggest that capacitance currents stimulus in electronic view may be important factor in acupuncture therapy between the operator and the receiver of acupuncture therapy.

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전실업무와 연계간호에 대한 신경계 중환자실 간호사의 인식 (Perception of Transfer Job and Liaison Nursing among Nurses in Neurological Intensive Care Units)

  • 윤선희;조옥희;유양숙
    • 임상간호연구
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    • 제19권1호
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    • pp.115-127
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    • 2013
  • Purpose: This study aimed to describe how nurses in neurological intensive care units (ICU) perceive their roles about patient transfer and liaison. Methods: A cross-sectional survey was conducted using a questionnaire developed for the study. Data were collected from a convenience sample of 115 nurses working in the neurological intensive care units ofsix university hospitals. Data were analyzed using SPSS software (version 15.0). Results: Staff nurses were mainly in charge of patient transfer, and the awareness about its importance was significantly related with the burden about the practice of patient transfer (p<.001). Patient liaison was mainly conducted by staff nurses as well. Liaison practice wassuggested to be started from the ICU at the time of transfer; the suggested time for completion of liaison service and evaluation was when patients were adjusted to the transferred ward. Preparing job descriptions and increasing nursing staffing for patient liasion service were strongly recommended. Conclusion: The results suggest that the ICU nurses' burden in relation to patient transfer is commensurate with their awareness about itsimportance. To improve the continuity of care from ICU to transferred ward, it isrequired to reduce the burden about patient transfer and improve perceptions about patient liaison.