Publications by authors named "Heesoo Jung"

Chemical warfare agents (CWAs) pose a threat as gaseous substances and as liquid aerosols, necessitating chemical warfare-protective clothing for soldiers. The paramount consideration lies in the effectiveness of the clothing as a barrier against the pertinent CWAs. This paper presents a dynamic swatch test method aimed at evaluating the performance of such clothing against liquid-phase aerosol penetration.

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This study proposes a predictive model for assessing adsorber performance in gas purification processes, specifically targeting the removal of chemical warfare agents (CWAs) using breakthrough curve analysis. Conventional parameter estimation methods, such as Brunauer-Emmett-Teller analysis, encounter challenges due to the limited availability of kinetic and equilibrium data for CWAs. To overcome these challenges, we implement a Bayesian parametric inference method, facilitating direct parameter estimation from breakthrough curves.

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The application of ultraviolet (UV) light for the decontamination of chemical warfare agents (CWAs) has gained recognition as an effective method, especially for treating hard-to-reach areas where wet chemical methods are impractical. In this study, TiO/Ti was employed as a model catalyst, which was contaminated with 2-chloroethyl phenyl sulfide (CEPS), and subjected to photocatalytic decontamination using both UVB and UVC light. Additionally, photocatalytic decontamination efficiency by introducing Au, Pt, and Cu onto the TiO/Ti surface was explored.

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Personal protective equipment against chemical warfare agents and other toxic chemicals must be protective, be breathable, and have a low thermal burden. Selectively permeable membranes are promising candidates for such equipment. In this study, a hybrid membrane consisting of a continuous and thin zeolitic imidazolate framework (ZIF)-8 layer on an oxygen-rich small-flake graphene oxide layer was produced using a simple and scalable synthesis method.

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Article Synopsis
  • Novichoks, a type of toxic chemical, pose significant environmental risks, and effective decontamination methods are crucial for their neutralization, particularly A-234, a nerve agent.
  • This study conducted detailed experiments using various analytical methods to examine A-234's persistence in the environment and the effectiveness of different decontaminants.
  • Results indicate that A-234 remains stable in sand and is resistant to many traditional decontaminants, but can be effectively neutralized within 30 minutes using specific agents like Oxone® and calcium hypochlorite.
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With the growing interest in chemical and biological warfare agents (CWAs/BWAs), the focus has shifted toward aerosol protection using protective clothing. However, compared to air-permeable membranes, those with water vapor permeability have been investigated more extensively. Filtering membranes without air permeability have limited practical usage in personal protective suits and masks.

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Due to the widespread emergence of COVID-19, face masks have become a common tool for reducing transmission risk between people, increasing the need for sterilization methods against mask-contaminated microorganisms. In this study, we measured the efficacy of ultraviolet (UV) laser irradiation (266 nm) as a sterilization technique against spores and on three different types of face mask. The UV laser source demonstrated high penetration of inner mask layers, inactivating microorganisms in a short time while maintaining the particle filtration efficiency of the masks.

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  • Researchers are developing sustainable alternatives to long-chain fluorinated compounds used in nonwetting coatings due to regulatory concerns.
  • A new copolymeric coating made from short-chain fluorinated groups was created, demonstrating strong nonwetting properties against chemical warfare agents and showing a unique bumpy texture that enhances performance.
  • The coating maintains its effectiveness and structure after extensive testing against wear and harsh chemicals, indicating its potential for durable military fabric applications with better health and environmental safety.
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Chemical warfare agents (CWAs) are toxic materials that cause death by contact with the skin or by respiration. Although studies on detoxification of CWAs have been intensively conducted, studies that block CWAs permeation are rare. In this study, for blocking CWAs, a multilayer thin film composed of linear polyethylenimine (LPEI) and graphene oxide (GO) is simply prepared through a spray-assisted Layer-by-Layer (LbL) assembly process.

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spores are highly resistant to toxic chemicals and extreme environments. Because some species threaten public health, spore inactivation techniques have been intensively investigated. We exposed spores to a 266 nm Nd:YVO laser at a laser power of 1 W and various numbers of scans.

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Composites of metal-organic frameworks and carbon materials have been suggested to be effective materials for the decomposition of chemical warfare agents. In this study, we synthesized UiO-66-NH/zeolite-templated carbon (ZTC) composites for the adsorption and decomposition of the nerve agents sarin and soman. UiO-66-NH/ZTC composites with good dispersion were prepared via a solvothermal method.

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The development of efficient adsorbents to remove radioactive methyl iodide (CHI) in humid environments is crucial for air purification after pollution by nuclear power plant waste. In this work, we successfully prepared a post-synthetic covalent modified MIL-101 with a sulfonate group followed by the ion-exchange of Ag (I), which is well characterized by diffuse reflectance FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS) and the hydrophobic index (HI). After modification of the MOFs, we applied functionalized MIL-101 obtained by either one-pot synthesis (MIL-101-SOAg) or a post-synthetic modification process (MIL-101-RSOAg, R = NH(CH)) to remove the CHI at an extremely low concentration (0.

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Using a lotus leaf as our model, we fabricated an extremely low surface energy micro/nanostructured coating for textiles that repel oil, water, and chemical warfare agents (CWAs) using a simple process that is suitable for large scale production. This coating, called "OmniBlock", consisted of approximately 200-nm silica nanoparticles, tetraethylorthosilicate, 3-glycidoxypropyl trimethoxysilane, and a perfluorooctanoic acid-free fluoropolymer (Fluorolink S10) that was cross-linked between Si-O-Si groups via a sol-gel process. The perfluorooctanoic acid-free fluoropolymer-coated silica nanoparticles were simply applied to the surface of a cotton fabric by a dip-dry-cure process, forming dense, continuous, and uniform layers of OmniBlock coating.

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Zirconium hydroxide, Zr(OH) is known to be highly effective for the degradation of chemical nerve agents. Due to the strong interaction force between Zr(OH) and the adsorbed water, however, Zr(OH) rapidly loses its activity for nerve agents under high-humidity environments, limiting real-world applications. Here, we report a nanocomposite material of Zr(OH) and graphene oxide (GO) which showed enhanced stability in humid environments.

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One of the key reasons for the limited use of atmospheric pressure plasma (APP) is its inability to treat non-flat, three-dimensional (3D) surface structures, such as electronic devices and the human body, because of the rigid electrode structure required. In this study, a new APP system design-wearable APP (WAPP)-that utilizes a knitting technique to assemble flexible co-axial wire electrodes into a large-area plasma fabric is presented. The WAPP device operates in ambient air with a fully enclosed power electrode and grounded outer electrode.

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Article Synopsis
  • Bacterial wilt and grey mould are harmful diseases affecting tomato plants, caused by specific bacteria and fungi, which have led to the exploration of control methods.
  • The study tested four vitamins (thiamine, niacin, pyridoxine, and menadione) to see how well they could help protect tomatoes from these diseases, finding that thiamine was notably effective in reducing bacterial wilt.
  • All vitamins showed varying levels of effectiveness in inhibiting fungal growth, with menadione showing significant results in reducing conidial germination and mycelial growth, suggesting that vitamin treatments could be a viable, eco-friendly option for managing these plant diseases.
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Anthracnose caused by Colletotrichum gloeosporioides has been destructive during pepper fruit production in outdoor fields in Korea. In vitro antifungal activities of 15 different plant essential oils or its components were evaluated during conidial germination and mycelial growth of C. gloeosporioides.

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A key challenge to the industrial application of nanotechnology is the development of fabrication processes for functional devices based on nanomaterials which can be scaled up for mass production. In this report, we disclose the results of non-thermal radio-frequency (rf) atmospheric pressure plasma (APP) based deposition of TiO2 nanoparticles on a flexible substrate for the fabrication of dye-sensitized solar cells (DSSCs). Operating at 190 °C without a vacuum enclosure, the APP method can avoid thermal damage and vacuum compatibility restrictions and utilize roll-to-roll processing over a large area.

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Renal dysfunction is a common comorbidity in patients with liver failure and is a well-established predictor of both morbidity and mortality among patients awaiting liver transplantation. The etiology of renal failure in patients with cirrhosis can be functional, structural, or represent a combination of potentially reversible physiologic changes and permanent histologic damage. Diagnostic criteria for acute and chronic kidney disease have been established, but cirrhosis poses challenges for accurate assessment of renal function with conventional clinical methods such as serum creatinine and creatinine-based estimating equations.

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An apparatus for generating atmospheric pressure plasma (APP) jet was used to investigate the inactivation of Listeria monocytogenes on the surface of agar plates and slices of cooked chicken breast and ham. He, N₂ (both 7 L/min), and mixtures of each with O₂ (0.07 L/min) were used to produce the plasma jets.

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Ultraviolet nanoimprint lithography (UV-NIL) is a high volume and cost-effective patterning technique with sub-10 nm resolution. It has great potential as a candidate for next generation lithography. Using UV-NIL, nanowire patterns were successfully fabricated on a four-inch silicon-on-insulator (SOI) wafer under moderate conditions.

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Atmospheric pressure plasma (APP) is an emerging non-thermal pasteurization method for the enhancement of food safety. In this study, the effect of APP on the inactivation of pathogens inoculated onto bacon was observed. Sliced bacon was inoculated with Listeria monocytogenes (KCTC 3596), Escherichia coli (KCTC 1682), and Salmonella Typhimurium (KCTC 1925).

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This paper describes the resistive switching of a cross-point cell array device, with a junction area of 100 nm x 100 nm, fabricated using ultraviolet nanoimprinting. A GdO(x) and Cu-doped MoO(x) stack with platinum top and bottom electrodes served as the resistive switching layer, which shows analog memory characteristics with a resistance ratio greater than 10. To demonstrate a neural network circuit, we operated the cell array device as an electrically modifiable synapse array circuit and carried out a weighted sum operation.

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