• Title/Summary/Keyword: fuming

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The studies of developing latent fingerprint in general print papers by chemical reaction (화학반응을 이용한 일반 프린트용지의 잠재지문 현출에 관한 연구)

  • Roh, Seung-Chan;Choi, Mi-Jung;Kim, Man-Ki;Lee, Oho-Taick;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.20 no.2
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    • pp.155-163
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    • 2007
  • Porosity paper evidence is encountered in case of forgery, kidnapping, fraud and terrorist activity. The present study was designed to evaluate the effect of three chemical reagents (Ninhydrin, 1,8-diazafluoren-9-one (DFO), Iodine fuming) to the quality of developed latent fingerprints on porosity printing papers and newspaper. In case of printing papers, print quality was better with Iodine fuming method than Ninhydrin and DFO treatment to developing latent fingerprints. Developing latent fingerprint on newspapers was achieved with Iodine fuming processing. The processing of Iodine fuming followed by DFO and by using blue light (orange red filter) exhibited better results with Iodine fuming. Enhancement of latent fingerprint detection image using Digital Imaging System was achieved.

A study on the optimal conditions for latent fingerprint development using cyanoacrylate fuming method in vacuum chamber (시아노아크릴레이트 진공 훈증법에 의한 잠재지문 현출 최적화에 관한 연구)

  • Yu, Je-Seol;Jung, Jin-Sung;Lim, Seung;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.25 no.3
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    • pp.164-170
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    • 2012
  • Cyanoacrylate fuming mehod is effective for latent fingerprints developing on non-porous surfaces. In this study, we investigated optimal conditions for latent fingerprint development using cyanoacrylate fuming method in vacuum chamber. The effects of temperature, relative humidity, fuming method and processing time were checked throughly. The amount of evaporated cyanoacrylate was increased at higher temperature, but cyanoacrylate polymerization on the fingerprint ridge was best at $30^{\circ}C$. With a relative humidity of 40% to 50% conditions, good quality of fingerprints were developed. If a relative humidity is lower than 30% or higher than 60%, polymerization rate of cyanoacrylate monomers on the fingerprint ridge was decreased. It was identified that application of $OMEGA-PRINT^{TM}$ dispersal pad or cotton ball with sodium hydroxide fuming method in vacuum chamber was more effective than natural fuming method. We found that cyanoacrylate processing time in vacuum chamber did not have more significant than relative humidity.

Comparison of aging fingerprint enhancement by pre-treatment of various initiator powders in the cyanoacrylate fuming method (다양한 개시제(initiator)분말 전처리(pre-treatment)를 통한 노화된 지문의 Cyanoacrylate Fuming법 현출 증강 비교)

  • Kim, Kyung-Soo;Lee, Yoon-Jeong;Seo, Kyung-Suk
    • Analytical Science and Technology
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    • v.35 no.3
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    • pp.129-135
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    • 2022
  • We tested the pre-treatment of alumina, leucine, alumina mixed with leucine at ratios of 9:1 (Al-Leu (9:1)) and 5:1 (Al-Leu (5:1)), and alumina mixed with sodium lactate at a ratio of 5:1 (Al-Lac (5:1)) on aged fingerprints (1, 7, 14, and 30 days after natural fingerprinting) before cyanoacrylate (CA) fuming to improve the development efficacy. As a result of the experiment, fingerprints with pre-treatment of alumina, leucine, Al-Leu (9:1), Al-Leu (5:1), and Al-Lac (5:1) showed better development efficacy (area and minutiae) than fingerprints without pre-treatment. Therefore, this modified CA fuming method improved the development efficacy with five pretreatments.

A Study on How to Improve Empty Print to Cyanoacrylate Fuming Developed by Vacuum Metal Deposition (Vacuum Metal Deposition으로 현출된 Empty Print를 Cyanoacrylate Fuming로 개선하는 방법에 관한 연구)

  • Lee, Wonyoung;Kim, Youjin;Lee, Munhee;Yu, Jeseol
    • The Journal of the Korea Contents Association
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    • v.21 no.12
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    • pp.331-336
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    • 2021
  • Vacuum metal deposition(VMD) using gold and zinc is known as a very sensitive technique of developing latent fingerprints on nonporous surfaces by excellent malleability and ductility of gold. However, VMD produces empty print which cannot be identified. There is only presumption about the cause of occurrence of empty print, the exact cause is not known. In this study, we experiment on the freshness of fingerprints and sensitivity of techniques that are estimated as the factors causing empty print, based on this, we suggest cyanoacrylate fuming is effective to redevelop empty print.

Developing of latent fingerprint on human skin (생체피부에서의 잠재지문 현출)

  • Lee, Hee-Il;Choi, Mi-Jung;Kim, Jai-Hoon;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.21 no.3
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    • pp.222-228
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    • 2008
  • On living skin the chances of a successfully developing latent fingerprint are very limited. This is due to the fact that continual perspiration and rapid absorption diffuse into the lipophillic layer on skin. A study was conducted to investigate effectively developing method of latent fingerprints on human skin surfaces and pig skin likely corpse's skin. We used commercial fingerprint powder, black powders, black magnetic powder, fluorescence magnetic powder, Cyanoacrylate fuming (CA) and direct lifting methods (lifting paper, glasses and photo glossy paper). Developing of fresh fingerprints on living skin was achieved with S-powderblack, CA fuming and CA fuming following S-powder, fluorescence powder. The other powder tends to overwhelm the latent print and the background. But, latent fingerprint residue was disappeared with time after deposit on a living surface. In case of pig skin likely corpse's skin, latent fingerprint detection was achieved with CA fuming following S-powder and deposited print during 6 hr at $25^{\circ}C$, 40% relative moisture yielded excellent fingerprints with clear ridge details using 1 min CA fuming. And enhancement of fingerprint detection image using forensic light source was achieved.

Latent fingerprint development from rubber gloves using MMD I (Multimetal deposition I)

  • An, Jaeyoung;Kim, Heesu;Oh, Jungmin;Han, Sooyong;Yu, Jeseol
    • Analytical Science and Technology
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    • v.33 no.2
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    • pp.108-114
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    • 2020
  • Gloves are very important evidence at a crime scene; specifically, rubber gloves can be found easily at homes. Therefore, crime scene investigators attempt to develop fingerprints inside the rubber gloves that are discovered, for identifying unknown suspects. This study compared the effectiveness of three different methods that are used for developing latent prints on gloves with aging time. These were the powder, cyanoacrylate fuming, and multi-metal deposition I methods. The powder method achieved good results for 1-3 days of aged prints, and the cyanoacrylate fuming method worked well on 2-week-old prints. In comparison, multi-metal deposition I method developed good quality fingerprints for 6 weeks of aging time.

Characteristics of Surface Roughness in Micro fuming using PCD Tools (PCD공구를 이용 미소가공시 표면거칠기 특성)

  • 한복수;이소영
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.10 no.5
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    • pp.31-38
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    • 2001
  • This paper deals with the micro turning property of setting angle using diamond tool. The bed of the system has used the granite which has the thermal and vibrational characteristics superior to the cast iron bed for the common machine tool. To minimize the inner and outer vibration of the fuming system, an air pad system was manufactured and tested. The aero-static spindle system which has the excellent rotation accuracy was designed and manufactured. As a result of the micro-cutting test on aluminum alloy, tool setting angel have effected on surface roughness. From the results, the micro-cutting conditions hope to provide the useful actual data using in industrial fields.

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Mixture of dimethylaminobenzaldehyde and cyanoacrylate to develop fingerprints with fluorescence: a preliminary test

  • Lee, Wonyoung;An, Jaeyoung;Yu, Jeseol
    • Analytical Science and Technology
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    • v.35 no.1
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    • pp.1-7
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    • 2022
  • This study suggests a new one-step fluorescent cyanoacylate-fuming method for developing fingerprints by using a CAB mixed with dimethylaminobenzalde (DMAB) and cyanoacylate (CA) in a specific ratio. CAB is prepared by mixing 2.5 % (w/w) DMAB with CA and fumigated at 180 ℃. Under these conditions, developing fingerprints showed the best results. The fuming method using CAB develops latent fingerprints into fluorescence and has a higher sensitivity than CA, and it showed comparable or better contrast to existing fluorescence enhancement methods. It was also applicable on a variety of non-porous surfaces that can be encountered at ordinary times. This method is more useful than conventional fluorescent dyeing methods in that it minimizes damage to fingerprints or samples, makes it easy to manufacture, saves time, and can use existing current equipment as it is.

Studies on the Separation and Concentration Method of $^{90}Sr$ in the Environmental Samples (환경시료 중 $^{90}Sr$의 분석을 위한 분리농축법 연구)

  • Won, Mi Sook;Cho, Kyu Bong;Yoon, Jang Hee;Lee, Dae Won;Shim, Yoon Bo
    • Analytical Science and Technology
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    • v.14 no.1
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    • pp.8-14
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    • 2001
  • New process to determine $^{90}Sr$ in the environmental samples was established by investigating the existing methods. The environmental samples included soil, milk, seaweed, fishes and clams, pine needles, and marine sediment. Using the developed method combined with fuming nitric acid and ion exchange resin, which could be reduced the treatment step, we could be removed Ca effectively for the determination of $^{90}Sr$. The recovery yield of $^{90}Sr$ in this method was 10% higher than those of using the fuming nitric acid only. This method could be applied to all environmental samples we choose. The content of $^{90}Sr$ in soil was the highest value in the tested environmental samples.

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A Study on Improvement of Storage Safety through Quality improvement of Torpedo Propulsion Battery (어뢰 추진전지 품질개선을 통한 저장안정성 향상에 관한 연구)

  • Jang, Min-Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.7
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    • pp.291-298
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    • 2019
  • We describe the improvement of insulation performance and the prevention of electrolyte leakage in a single cell in order to prevent the fuming phenomenon caused by leakage of electrolyte in a lithium secondary battery in a submerged weapon (torpedo) operated in Korea. A torpedo using lithium secondary battery as a main power source (propulsion battery) can induce the heat and fuming phenomenon, which makes it inconvenient for naval equipment operation in Korea. In the simulation test, the electrolyte of some battery cells leaked in the battery pack unit, leading to a short circuit between the main power circuit and the terminal tab of the high voltage part. We analyzed the characteristics and mechanism of the lithium secondary battery during this heat generation and fuming phenomenon. In order to prevent leakage of the electrolyte in the lithium secondary battery, the design was improved via fundamental (terminal tap enhancement) and complementary (insulation block selection and installation) measures. Comparison of the performance test before and after the improvement showed that the tensile strength of the tap terminal was improved about 2 times and the withstand voltage characteristic was improved. The application of quality improvement measures resulted in no fuming even after more than 3 years of field operation. This result is expected to improve the operation and storage stability of the torpedo propulsion cell.