• 공업화학
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• 제32권5호
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• pp.524-531
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• 2021

UiO-66은 높은 흡착능력과 구조적 및 열적 안정성 등으로 여러 현장에 적용 가능한 금속유기골격체(MOF)이다. UiO-66은 제조과정에서 조절인자로 사용되는 산의 종류와 양에 따라 구조적 특성이 변형되고, 화학작용제 흡착 능력을 높일 수 있다고 알려져 있다. 이에 본 연구에서는 다양한 산을 조절인자로 첨가하여 UiO-66을 합성하고, 그 특성을 FT-IR, XRD, 적정장치, 그리고 유사화학작용제 diisopropyl methylphosphonate (DIMP)를 활용한 흡착실험을 통해 분석하였다. 연구 결과 UiO-66의 제조과정에서 염산을 첨가할 시 UiO-66의 Zr-OH 결합과 UiO-66의 유기연결체인 테레프 탈산 구조에 일부 손상이 있었다. 특히 이러한 구조 손상은 염산의 농도가 일정 수준 이상으로 높을 때, 그리고 합성 시간이 일정 시간 이상으로 길어질 때 발생하였다. 하지만 아세트산과 포름산을 조절인자로 활용하여 제조한 UiO-66은 구조적 손상이 발견되지 않았으며, 염산을 활용하여 제조한 UiO-66에 비하여 결정도, 비표면적, 공극의 부피, 그리고 DIMP 흡착 능력이 모두 높게 나타나 향후 화학작용제 흡착제로서 활용 가능성이 높을 것으로 판단되었다.

• 한국군사과학기술학회지
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• 제24권4호
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• pp.374-381
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• 2021

Raman spectrometers are studied and developed for the military purposes because of their nondestructive inspection capability to capture unique spectral features induced by molecular structures of colorless and odorless chemical warfare agents(CWAs) in any phase. Raman spectrometers often suffer from random noise caused by their detector inherent noise, background signal, etc. Thus, reducing the random noise in a measured Raman spectrum can help detection algorithms to find spectral features of CWAs and effectively detect them. In this paper, we propose a denoising autoencoder for Raman spectra with a loss function for sample efficient learning using noisy dataset. We conduct experiments to compare its effect on the measured spectra and detection performance with several existing noise reduction algorithms. The experimental results show that the denoising autoencoder is the most effective noise reduction algorithm among existing noise reduction algorithms for Raman spectrum based standoff detection of CWAs.

• Journal of Korean Society for Atmospheric Environment
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• 제20권E2호
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• pp.69-75
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• 2004

In this study, thin film gas sensor based on tin oxide was fabricated to examine its characteristics. Target gas is acetonitrile ($CH_3$CN) which is a blood simulant for the chemical warfare agent. Sensing materials are SnO$_2$ SnO$_2$/Pt, and Sn/Pt with thickness from 1000 to 3000 $\AA$. The sensor consists of a sensing electrode with inter-digit (IDT) type in front side and a heater in rear side. Resistance changes of sensing materials are monitored on real time basis using a data acquisition board with a 12-bit analog to digital converter. Sensitivities are measured at different operating temperatures also with different gas concentrations and film thickness. The high sensitivity is obtained for Sn (3000 $\AA$)/Pt (30 $\AA$) at 30$0^{\circ}C$ for 3 ppm. Response and recovery times were about 40 and 160 s, respectively. Repetition measurements showed very good results with $\pm$3% in full scale range.

• 한국군사과학기술학회지
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• 제17권1호
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• pp.122-128
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• 2014

Remote fourier transform infrared(FTIR) chemical imaging detection system allows detection and identification of gases in the atmosphere from long distances. In this paper, the appropriate field of view(FOV) of the FTIR imaging system was examined and the main performance of the system for the interferometer was described. For the determination of the FOV, simulations of gas dispersion range were performed with the NBC reporting and modeling software(NBC-RAMS) developed by ADD. As a result, minimum 192 mrad of FOV was required for the remote FTIR imaging system to visualize chemical warfare agents dispersed in several hundred meters. At the same time, 0.75 mrad of instantaneous field of view(IFOV) for a linear interferometer proper to take a FOV for the chemical agent imaging.

• 한국군사과학기술학회지
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• 제7권2호
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• pp.81-87
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• 2004

Semiconductor thick film gas sensors based on tin oxide are fabricated and their gas response characteristics are examined for four simulant gases of chemical warfare agent (CWA)s. The sensing materials are prepared in three different sets. 1) The Pt or Pd $(1,\;2,\;3\;wt.\%)$ as catalyst is impregnated in the base material of $SnO_2$ by impregnation method.2) $Al_2O_3\;(0,\;4,\;12,\;20\;wt.\%),\;In_2O_3\;(1,\;2,\;3\;wt.\%),\;WO_3\;(1,\;2,\;3\;wt.\%),\;TiO_2\;(3,\;5,\;10\;wt.\%)$ or $SiO_2\;(3,\;5,\;10\;wt.\%)$ is added to $SnO_2$ by physical ball milling process. 3) ZnO $(1,\;2,\;3,\;4,\;5\;wt.\%)$ or $ZrO_2\;(1,\;3,\;5\;wt.\%)$ is added to $SnO_2$ by co-precipitation method. Surface morphology, particle size, and specific surface area of fabricated sensing films are performed by the SEM, XRD and BET respectively. Response characteristics are examined for simulant gases with temperature in the range 200 to $400^{\circ}C$, with different gas concentrations. These sensors have high sensitivities more than $50\%$ at 500ppb concentration for test gases and also have shown good repetition tests. Four sensing materials are selected with good sensitivity and stability and are fabricated as a sensor array A sensor array Identities among the four simulant gases through the principal component analysis (PCA). High sensitivity is acquired by using the semiconductor thick film gas sensors and four CWA gases are classified by using a sensor array through PCA.

• 공업화학
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• 제33권3호
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• pp.296-301
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• 2022

UiO-66과 같은 지르코늄 기반 금속유기골격체(Zr-MOFs)는 비표면적이 넓고 선택적 흡착 능력이 뛰어나 전장환경에서 화학작용제 방호 물질로써 주목받고 있다. 하지만 대부분의 금속유기골격체는 약한 금속-유기 리간드 결합과 공극의 존재로 인하여 대기 중에 노출 시 물 분자와의 반응으로 선택적 흡착 성능이 저하되는 문제점이 있다. 이에 본 연구에서는 대표적인 소수성 고분자 물질인 폴리디메틸실록산(PDMS)을 지르코늄 기반 금속유기골격체인 UiO-66 표면에 코팅하였고, 전장환경에서 적용 가능성을 평가하기 위해 고습 환경에서 diisopropyl methylphosphonate (DIMP)와 같은 유사 화학작용제의 흡착 성능 지속성을 코팅 전과 비교하였다. PDMS를 코팅한 UiO-66의 표면 구조와 유기 작용기 분포를 분석한 결과 실리콘이 고르게 도포된 것을 확인하였으며, 접촉각을 측정한 결과 PDMS를 코팅한 UiO-66에서 30° 이상 접촉각이 증가하여 소수성이 증대한 것을 확인하였다. 또한 UiO-66과 PDMS를 코팅한 UiO-66을 흡착제로 사용하여 고습 환경에서 유사 화학작용제인 DIMP의 흡착 성능 지속성을 확인한 결과 PDMS를 코팅한 UiO-66가 기존의 UiO-66에 비하여 높은 DIMP 흡착 성능 지속성을 나타내는 것을 알 수 있었다.

• Korean Chemical Engineering Research
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• 제45권2호
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• pp.172-177
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• 2007

신경작용제의 일종인 고농도의 사린(GB)을 무해한 물질로 전환하기 위한 실험 조건을 찾기 위하여 가성소다 수용액으로 가수분해 하였다. 가수분해 반응은 쟈켓이 부착된 소형 반응기에 circulator를 연결하여 사용하고 2.05 당량의 가성소다 용액에 농도 10 wt%의 사린을 주입한 후 각각의 반응온도(50, 70 및 $90^{\circ}C$)에서 반응 속도 상수를 구하고 이를 이용하여 각 온도에서 GB를 99% 이상 분해하는데 소요되는 가수분해 시간을 예측하였다. 가수분해 실험 결과 GB는 $90^{\circ}C$에서 1.2 시간 반응하면 99.99% 이상 분해되었으며 주요 분해생성물은 isopropyl methylphosphonate이었다.

• Korean Chemical Engineering Research
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• 제45권3호
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• pp.291-297
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• 2007

수포작용제의 일종인 sulfur mustard(HD, bis 2-chloroethylsulfide)를 무해한 물질로 전환하기 위한 공정 운영조건을 찾기 위하여 물에 의한 HD 가수분해 반응을 연구하고 분석절차를 수립하였다. 반응은 2단계로 진행하였다. 먼저, HD 10~20 wt%를 $90^{\circ}C$ 물에서 2시간 동안 가수분해 한 후 상온에서 가성소다 수용액(2.1 당량)을 주입하면서 반응시간에 따른 HD의 농도변화를 측정하였다. 이 실험조건에서 HD의 분해효율은 99.99% 이상 이었으며 가수분해 후의 최종 분해물질은 thiodiglycol 68 wt%, 1,2-bis(2-hydroxyethylthio)ethane 8 wt% 및 bis(2-hydroxyethylthioethyl)ether 24 wt% 이었다.

• 한국군사과학기술학회지
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• 제18권4호
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• pp.387-394
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• 2015

We have recently developed a cost-effective and pouch-type chemical vapor sampler which consists of a selectively permeable high density polyethylene(HDPE) membrane, aluminum/nylon barrier film, and adsorbents. Since the sampler mimics the actual adsorption process that occurs when the skin is exposed to chemical vapors, it can be applied to man-in-simulant test(MIST) to determine the protective capability of individual protective ensembles for chemical warfare agents. In this study, we describe the manufacturing process of samplers and results for performance testing on MIST. Methyl salicylate(MeS) is used to simulate chemical agent vapor and the vapor sampler was used to monitor chemical concentration of MeS inside the protective suit system while worn. Values of protection factors(PF) were also analyzed to provide an indication of the protection level of the suit system evaluate by MIST. The results obtained by home-made samplers(ADD samplers) and commercially avaliable ones(Natick samplers) showed no significant differences.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7567-7573
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• 2015

Background: Catastrophic effects of mustard gas as a chemical warfare agent have always been a major problem for those exposed to this agent. In this meta-analysis it was tried to evaluate carcinogenesis, ocular, cutaneous and respiratory complications of mustard gas exposure among Iranians who had been exposed to this agent during the Iran-Iraq war. Materials and Methods: In this meta-analysis, the required data were collected using keywords "mustard gas", "sulfur mustard", "cancer", "neoplasm", "respiratory complications", "ocular complications", "lung disease", "chronic complication", "eye", "skin", "cutaneous complication", "carcinogenesis" and their combination with keywords "Iran", "Iranian", "prevalence", "mortality" and their Farsi equivalent terms from the databases of SID, Iranmedex, Magiran, Pubmed, Science Direct, Google Search engine, Gray Literature and Reference of References. To determine the prevalence of each complication and perform meta-analysis, CMA: 2 (Comprehensive Meta-Analysis) software with a randomized model was used. Results: Of the 542 articles found, 7 national articles, consistent with the aims of this study were selected. Meta-analysis of seven papers revealed that cancer risk, especially cancer of the respiratory system was elevated, so that the relative risk (RR) of cancer role of mustard gas was inconsistent from 2/1 to 4 in this survey. Also prevalence of delayed skin disorders due to sulfur mustard was 94.6%, pulmonary complications 94.5% and ocular complications 89.9%. The incidence of various cancers in victims exposed to mustard gas was 1.7% worldwide where the rate was 2.2% in Iranian victims of the Iraq-Iran war. Conclusions: Based on present study the prevalence of delayed mustard gas related cutaneous, pulmonary and ocular complications is above 90% and risk of carcinogenesis is higher in comparison to worldwide statistics. This may suggest need for long-term and persistent follow-up and rehabilitation procedures for populations exposed to this agent.