• 수산해양기술연구
• /
• 제58권4호
• /
• pp.334-344
• /
• 2022

In this study, we used underwater acoustics to analyze the spatial and temporal distribution characteristics of largehead hairtail (Trichiurus leptueus) based on the luminous thronging of metal halide fishing lamps and induction fishing lamps. As a result, the illuminating power was approximately 1.3 times higher using the metal halide fishing lamp whereas the density of hairtals by distance was approximately 1.9 times higher using the induction fishing lamp. Regarding water depth distribution, hairtails were detected depths of 25-30 m during August and at all water depths in November as assessed using fishing lamps.

• Bulletin of the Korean Chemical Society
• /
• 제31권7호
• /
• pp.1937-1940
• /
• 2010

Ionic liquids with halide anions were prepared and the dependency of halide anions on the $SO_2$ solubility of ILs was investigated. The study shows that the $SO_2$ solubility of ionic liquids lies in the range 1.91~2.22 $SO_2$/ILs mol ratio. $SO_2$ solubility in ionic liquids with varying halide anions follows the order Br > Cl > I. Theoretical investigation was also conducted at the B3LYP level using the Gaussian 03 program. From the theoretical consideration of the interaction between $SO_2$ and [EMIm]X (where X = Cl, Br, and I), it has been proposed that primary interaction of halide occurs with $C_2$-H of the imidazolium and S of $SO_2$. Experimental results further shows that the absorption and desorption process of $SO_2$ in ILs was reversible by the three cycles of the absorption at $50^{\circ}C$ and desorption at $140^{\circ}C$. The reversibility of $SO_2$ absorption was confirmed by FT-IR studies.

• International Journal of Internet, Broadcasting and Communication
• /
• 제7권2호
• /
• pp.16-27
• /
• 2015

Holography technology which was developed by Dennis Gabor (1900~1979) in 1948 is a technology to record wave planes of actual 3D objects. It is known as the only technology which can express 3D information most perfectly close to human-friendly. Holography technology is widely used in advertisement, architecture and arts as well as science technology areas. Especially, digital holographic print which is an applied area is greatly used in military map, architecture map and cultural asset restoration by printing and reproducing 3D information. Holography is realized by recording and reproducing the amplitude and phase information on high resolution film using coherent light like laser. Recording materials for digital holographic printer are silver halide, photoresist and photopolymer. Because the materials have different diffraction efficiency according to film characteristics of each manufacturer, appropriate guide lines should be suggested through efficiency analysis of each film. This paper suggests appropriate guide lines through the diffraction efficiency measurement of silver halide which is a holographic printer recording medium. And the objective of this study is to suggest appropriate guide lines through diffraction efficiency analysis of Ultimate 08-C and PFG-03C which are commercially used. The experiment was prepared by self-diffraction efficiency system which measures the strength with the defector by penetrating RGB recording medium and concentrating diffracted beams through collimating lens. The experiment showed Geola's PFG-03C which is a silver halide for full color has price/performance advantage in optical hologram recording, but recording angles and reproduction angles are irregular for digital holographic printer recording. Ultimate's Ultimate08-C for full color shows its diffraction efficiency is relatively stable and high according to recording angles and laser wavelength.

• 전기학회논문지
• /
• 제58권12호
• /
• pp.2446-2452
• /
• 2009

A Ceramic Metal-halide lamp is achieved by adding multiple metals to a basic mercury discharge. Because the vapor pressure of most metals is very much lower than mercury itself, metal-halide salts of the desired metals, having higher vapor pressures, are used to introduce the material into the basic discharge. The metal compounds are usually polyatomic iodides, which vaporize and subsequently dissociate as they diffuse into the bulk plasma. Metals with multiple visible transitions are necessary to achieve high photometric efficiency and good color. Compounds of Sc, Dy, Ho, Tm, Ce, Pr, Yb and Nd are commonly used. The maximum visible efficacy of a Ceramic Metal Halide lamp, under the constant of a white light source, is predicted to be about 450lm/W. This is controlled principally by the chemical fill chosen for a particular lamp. Current these lamps achieve 130lm/W and these life time are the maximum 16,000[hr]. So factors of performance lower are necessary to improve lamp performance. In this paper, we analyzed factors of performance lower by accelerated deterioration test. The lamp was operated with short duration turn-on/turn-off procedure to enhance the effect due to electrode sputtering during lamp ignition. The tested lamp that was operated with a longer turn-on/off(20/20 minutes) showed blackening, changed distance between electrodes and lowered color rendering & color temperature by losses of Dy at 421.18nm, I at 511nm, T1 at 535nm and Na at 588nm compared with the new lamp.

• Korean Chemical Engineering Research
• /
• 제45권4호
• /
• pp.364-371
• /
• 2007

본 연구에서는 연속상의 종류가 AOT 계면활성제 시스템의 water-in-oil(W/O) 마이크로에멀젼을 이용한 할로겐화은 나노입자 제조에 미치는 영향에 관하여 살펴보았다. 이를 위하여 계면활성제, 연속상 오일, 무기염 수용액으로 이루어진 삼성분 시스템에 대하여 탄화수소의 연속상 종류를 변화하면서 상평형 실험을 수행한 결과, 탄화수소의 사슬 길이가 증가함에 따라 계면활성제 시스템의 친수성이 증가하여 단일상으로 존재하는 W/O 마이크로에멀젼 영역은 증가하였다. 상평형 실험결과에 의하여 결정된 단일상의 영역 내에서 W/O 마이크로에멀젼을 이용하여 할로겐화은 나노입자를 제조한 결과, 10 nm 전후의 구형에 가까운 비교적 균일한 입자가 형성되었다. 사용한 연속상 탄화수소의 사슬 길이가 증가할수록 마이크로에멀젼의 film rigidity를 감소시킴에 따라 마이크로에멀젼 사이의 교환 속도가 빨라져서 생성된 할로겐화은 나노입자의 크기는 작아지고 반면에 개수는 증가하였다. 또한 동일한 시스템에서 무기염 수용액의 조성을 증가시킴에 따라 생성된 나노입자의 크기는 증가함을 알 수 있었다.

• Electronic Materials Letters
• /
• 제14권6호
• /
• pp.700-711
• /
• 2018

CdS synthesized by the chemical bath method at $70^{\circ}C$, has been used as an electron transport layer in the planar structure of the perovskite solar cells. A two-step spin process produced a mixed halide perovskite of $CH_3NH_3PbI_{3-x}Cl_x$ and a mixture of $PbCl_2$ and $PbI_2$ was deposited on CdS, followed by a sub-sequential reaction with MAI ($CH_3NH_3I$). The added $PbCl_2$ to $PbI_2$ in the first spin-step affected the structure, orientation, and shape of lead halides, which varied depending on the content of Cl. A small amount of Cl enhanced the surface morphology and the preferred orientation of $PbI_2$, which led to large and uniform grains of perovskite thin films. In contrast, the high content of Cl produces a new phase PbICl in addition to $PbI_2$, which leads to the small and highly uniform grains of perovskites. An improved surface coverage of perovskite films with the large and uniform grains maximized the performance of perovskite solar cells at 0.1 molar ratio of $PbCl_2$ to $PbI_2$. The depth profiling of elements in both lead halide films and mixed halide perovskite films were measured by Rutherford backscattering spectroscopy, revealing the distribution of chlorine along with the thickness, and providing the basis for the mechanism for enhanced preferred orientation of lead halide and the microstructure of perovskites.

• 한국재료학회지
• /
• 제32권10호
• /
• pp.419-424
• /
• 2022

Halide perovskite solar cells (PSCs) have improved rapidly over the past few years, and research on the optoelectrical properties of halide perovskite thin films has grown as well. Among the characterization techniques, photoluminescence (PL), a method of collecting emitted photons to evaluate the properties of materials, is widely applied to evaluate improvements in the performance of PSCs. However, since only photons emitted from the film in the escape cone are included, the photons collected in PL are a small fraction of the total photons emitted from the film. Unlike PSCs power conversion efficiency, PL measuring methods have not been standardized, and have been evaluated in a variety of ways. Thus, an in-depth study is needed of the methods used to evaluate materials using PL spectra. In this study, we examined the PL spectra of the perovskite light harvesting layer with different measurement protocols and analyzed the features. As the incident angle changed, different spectra were observed, indicating that the PL emission spectrum can depend on the measuring method, not the material. We found the intensity and energy of the PL spectra changes were due to the path of the emitted photons. Also, we found that the PL of halide perovskite thin films generally contains limited information. To solve this problem, the emitted photons should be collected using an integrating sphere. The results of this study suggest that the emission spectrum of halide perovskite films should be carefully interpreted in accordance with PL measuring method, since PL data is mostly affected by the method.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 B
• /
• pp.1129-1133
• /
• 2002

This paper presents an electronic ballast using a novel multiplex modulation method for the metal halide lamp. The proposed modulation method, which has a modulating signal of swept multiplex frequency, can eliminate the acoustic resonance more effectively than the conventional modulation method, which has a modulating signal of constant frequency. For the purpose of future application specific integrated circuits (ASIC), the controller of the proposed ballast has been designed only with erasable programmable logic devices (EPLDs), but without a microprocessor. In this paper, detailed proposed modulation schemes are described and experimental results on the proto-type 150W metal halide lamp ballast with the proposed modulation method are discussed.

• 한국세라믹학회지
• /
• 제55권6호
• /
• pp.515-526
• /
• 2018

Cesium lead halide ($CsPbX_3$) nanocrystals have emerged as a new family of semiconductor nanomaterials that can outperform existing semiconductor nanocrystals owing to their superb optical and charge transport properties. Although these materials are expected to have many superior properties, control of the quantum confinement and isoelectronic magnetic doping, which can greatly enhance their optical, electronic, and magnetic properties, has faced significant challenges. These obstacles have hindered full utilization of the benefits that can be obtained by using $CsPbX_3$ nanocrystals exhibiting strong quantum confinement or coupling between exciton and magnetic dopants, which have been extensively explored in many other semiconductor quantum dots. Here, we review progress made during the past several years in tackling the issues of introducing controllable quantum confinement and doping of $Mn^{2+}$ ions as the prototypical magnetic dopant in colloidal $CsPbX_3$ nanocrystals.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2009년도 하계학술대회 논문집
• /
• pp.378-379
• /
• 2009

High intensity metal halide discharge lamp performance, specifically the generated luminous flux and light color content, depends critically on the arc tube design. Factors influencing the design and consequent lamp efficacy include : lamp size, geometry, arc tube composition, fill chemistry, electrode design and excitation modes. Shaping of Polycrystalline Alumina(PCA) can be realized by conventional ceramic processes. Several processes are applied nowadays. Well-known in the ceramic high pressure field for decades are the pressing and the extrusion method. Newly developed slurry and precious forming technologies give the one-body seamless tubes, which improve thickness uniformity and lighting performance. Now, we reported some optical properties with different arc tube structures of ceramic metal halide lamps.