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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. In this study, polyacrylonitrile membranes with tightly attached activated carbon and doped copper(II) oxide were prepared via electrospinning. The nanofibers with uniformly controlled diameters and smooth morphologies enable water/air breathability and protection against aerosol (100 nm polystyrene nanobeads similar to SARS-CoV-2) penetration. The uniformly distributed and tightly attached activated carbon and doped copper(II) oxide particles enhance the sorptive performance of the membranes by blocking gaseous CWAs, including soman, nerve chemical agents, and BWAs. Such dual-purpose membranes can be implemented in protective equipment owing to their high performance and easy processing.

Ultraviolet (UV) radiation is one of the most common methods for sterilizing materials with suspected biological warfare agent contamination. In this study, UV laser sterilization of ceramic tiles was investigated as a method for destroying Bacillus atrophaeus spores. The effects of UV irradiation were evaluated as a function of water absorption (porous and vitrified), tile color (black and white), and surface brightness (matte and glossy). Spores were loaded onto the surface of each tile and irradiated with a 266-nm UV laser. The irradiated spores were then removed by scraping with a razor blade and cultured in an agar plate for 24 h. The sterilizing effects of the UV laser were greater on the vitrified (group BIb) tiles than on the porous (group BIII) tiles. In addition, sterilization was more effective on white and matte tiles than on black and glossy tiles, respectively.

Ultraviolet (UV) photodecontamination of chemical warfare agents (CWAs) has been an attractive way for decontamination of target areas unapproachable by a wet chemical method. Herein, decontamination was demonstrated using UV and infrared lamps and a home-built scanning 266-nm pulse laser under air and N2 conditions for the G-series nerve agent simulant model molecules of dimethyl methylphosphonate, dimethyl phosphite, diethyl methylphosphonate, and diethyl phosphite contaminating TiO2/Ti sheets. Volatile secondary photodecomposition products were examined by gas chromatography and mass spectrometry, and nonvolatile surface residues by X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction crystallography, and Fourier-transform infrared spectroscopy. The wavelength- and power-dependent mechanisms of the formation of diverse secondary products, the role of active O2−, h+ and •OH species, and the mechanisms of dissociative adsorption and photodecontamination were fully discussed and found valuable for the development of a remote laser photodecontamination method applicable to diverse CWA-contaminated target areas.

Researchers have studied victimization, fear of crime, and individuals’ behavioral characteristics to investigate the origin of crime and victimization, such as the routine activity theory. However, little research has examined how the behavioral characteristics were formed in theory. Although the elements of socioeconomic status, victimization experience, and fear of crime are believed to cause differences in human behaviors, the current study attempts to examine which predictors construct behavior characteristics like the routine activity theory, including target suitability and guardianship. Using the most recent, nationally collected official crime victimization data from South Korea (Korean Crime Victimization Survey, 2014), the study analyzed the variables with statistical models. The results suggest the following:(1) an individual’s socioeconomic status – such as gender, age, and education level – rather than victimization experience or fear of crime, are significant predictors of target suitability;(2) higher levels of fear of crime predict higher levels of guardianship; and (3) the victimization experience did not predict either target suitability or guardianship.

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

The ongoing concerns and regulations on long-chain fluorinated compounds (C8 or higher) for nonwetting coatings have driven the market to search for sustainable alternative chemistries. In this study, a copolymeric coating containing short-chain fluorinated groups was synthesized to achieve excellent nonwetting ability against hazardous chemical warfare agents (CWAs). A copolymer of 1

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. LPEI could change its morphology dependent on pH, which is known as a representative hydrogen donor and acceptor. By controlling the shape of the polymer chain, a heterogenous film could have a loose or dense inner structure. CWAs mainly move through diffusion and have hydrogen bonding sites. Therefore, the heterogeneous film can limit CWAs movement based on controlling pathways and hydrogen bonds within the film. The protective effect of this membrane is investigated using dimethyl methylphosphonate (DMMP), a nerve gas simulant. DMMP vapor transmittance rate (DVTR) and N2 permeance of LPEI/GO are 67.91 g/m2 and 34293.04 GPU. It means that the protection efficiency is 72.65%. Although this membrane has a thin thickness (100 nm), it shows a high protective effect with good breathability. And water/DMMP selectivity of the membrane is 66.63. Since this multilayer membrane shows efficient protection performance with a simple preparation method, it has a high potential for applications such as protective suits and masks.

A simple simultaneous complementary oil-water separation and water desalination system is designed using grafted glass fiber (GF) membranes. Non-fluorinated trialkoxysilanes are grafted to form superhydrophobic and superhydrophilic GF membranes, respectively. Zwitterion sulfobetaine was also synthesized and grafted on the glass fiber to make a superhydrophilic glass fiber membrane. The superwetting grafted GF membranes which are superhydrophobic had a water contact angle of 152° and high separation efficiency (>99%) for ten cycles and the superhydrophilic had an underwater oil contact angle of 156° and high separation efficiency (>98%) for ten cycles. The zwitterionic glass fiber membrane also exhibits excellent removal performance for heavy metal ions and nitrate ions from the water layer. This method is simple and scalable, and provides a versatile way for designing devices that achieve both oil/water separation and water desalination simultaneously.

The development of efficient adsorbents to remove radioactive methyl iodide (CH3I) 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-SO3Ag) or a post-synthetic modification process (MIL-101-RSO3Ag, R = NH(CH2)3) to remove the CH3I at an extremely low concentration (0.31 ppm) in an environment with very high relative humidity (RH 95%). Enhanced hydrophobicity of the surface-modified MIL-101 was evaluated by examining the HI with the competitive adsorption of water and cyclohexane vapor, with a high surface area maintained, as confirmed by Ar physisorption. Interestingly, the post-synthetically modified MIL-101-RSO3Ag showed exceptional adsorption performance as determined by its decontamination factor (DF = 195,350) at 303 K and RH 95%. This performance was in comparison to Ag (I)-exchanged 13X zeolite and MIL-101-SO3Ag, which include much higher amounts of Ag. Furthermore, MIL-101-RSO3Ag retained ~94–100% of its fresh adsorbent performance during five cycle repetitions.

Zirconium hydroxide, Zr(OH)4 is known to be highly effective for the degradation of chemical nerve agents. Due to the strong interaction force between Zr(OH)4 and the adsorbed water, however, Zr(OH)4 rapidly loses its activity for nerve agents under high-humidity environments, limiting real-world applications. Here, we report a nanocomposite material of Zr(OH)4 and graphene oxide (GO) which showed enhanced stability in humid environments. Zr(OH)4/GO nanocomposite was prepared via a dropwise method, resulting in a well-dispersed and embedded GO in Zr(OH)4 nanocomposite. The nitrogen (N2) isotherm analysis showed that the pore structure of Zr(OH)4/GO nanocomposite is heterogeneous, and its meso-porosity increased from 0.050 to 0.251 cm3/g, compared with pristine Zr(OH)4 prepared. Notably, the composite material showed a better performance for nerve agent soman (GD) degradation hydrolysis under high-humidity air conditions (80% relative humidity) and even in aqueous solution. The soman (GD) degradation by the nanocomposite follows the catalytic reaction with a first-order half-life of 60 min. Water adsorption isotherm analysis and diffuse reflectance infrared Fourier transform (DRIFT) spectra provide direct evidence that the interaction between Zr(OH)4 and the adsorbed water is reduced in Zr(OH)4/GO nanocomposite, indicating that the active sites of Zr(OH)4 for the soman (GD) degradation, such as surface hydroxyl groups are almost available even in high-humidity environments.

Understanding decomposition mechanism and analysis of secondary products for a chemical warfare agent (CWA) simulant on a contaminated target area are very important for better treatments of contaminated primary and secondary pollutants, and the development of a decontamination method. Herein, UV light (lamp and 266-nm laser high power pulses) photodecomposition method was introduced for the decontamination of G-series dimethyl methylphosphonate, dimethyl phosphite, diethyl methylphosphonate, and diethyl phosphite CWA model molecules contaminated on Mo and MoOx surfaces under various conditions. The secondary gas products were fully examined by gas chromatography and mass spectrometry, and the surface residues were also examined by scanning electron microscopy, Fourier-transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, and X-ray photoelectron spectroscopy before and after UV decontamination. Density function theory was employed to calculate the bond dissociation energies of the major chemical bonds for the CWA simulants. The full database for the photodecontamination products, the decomposition mechanism, the bond energies, and the roles of active species of O2−, h+ or OH reported in the present study provide valuable information on the development of future remote UV laser CWA decontamination system.

Decontamination of organophosphorus chemical warfare nerve agents (CWNAs) is gaining importance for human security. Herein, we have employed a dry-photodecontamination method for CWNA model molecules of dimethyl methylphosphonate, dimethyl phosphite, diethyl methylphosphonate, and diethyl phosphite contaminated on aluminum (Al) and oxidized Al foils. For understanding their photo-degradation pathways, the photo-decomposition secondary chemical products generated as a result of UVC-decontamination were fully examined for the contaminated Al and oxidized Al target areas in a closed reactor system by gas chromatography and mass spectrometry. Solid residues were also fully examined by X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy. Density functional theory at the B3LYP/6–31 G level was used for geometric optimization, and the electronic energy state calculation was conducted on the level of TD-SCF/B3LYP/6–31 G. The new results further deepen the photo-decomposition mechanism of CWNAs, the development of dry UV light photo-decontamination methods, and the treatment of secondary by-products.

In this study, UiO-66-NH2 and UiO-66-NH2/graphene oxide (GO) nanocomposites (5, 10 wt% GO) were synthesized with formic acid. The nanocomposites were isostructural with UiO-66-NH2 but with larger volumes of mesopores and micropores, particularly in 5 wt% GO in the composite (UiO-66-NH2/5GO). Moreover, the nanocomposites were found to be more resistant to high-humidity compared to UiO-66-NH2. UiO-66-NH2/GO nanocomposites containing 5 wt% GO exhibited more than 90% degradation of soman within 10 min even after being exposed to high-humid condition for 10 days, while it was less than 70% in the case of the pure UiO-66-NH2. Furthermore, soman, adsorbed in UiO-66-NH2/5GO, was degraded to pinacolyl methylphosphonic acid (PMPA) following pseudo-first-order reaction. This work closely represents how these composites work where they are deployed to protect against the nerve agent release, implying a broad range of practical applications of UiO-66-NH2/GO nanocomposites.

N–Cl functional groups have been widely utilized for antimicrobial and detoxification purpose. However, along with the high reactivity of N–Cl moiety, long term stability of N–Cl moiety under ambient condition is of special interest for final applications. Diverse organic moieties have been developed to enhance N–Cl stability, and hydantoin N–Cl groups are generally accepted as a promising candidate. Here, N–Cl functionalized electrospun nanofibers are prepared via surface functionalization method for fabrication of catalytic nanofiber mat against chemical warfare agent. Thermoplastic polyurethane (TPU) containing abundant pandent azide moiety is firstly synthesized, and nanofiber web is prepared via electrospinning. Hydantoin functional groups that are well-known moiety to stabilize N–Cl functional groups are introduced via surface click reaction. The storage stability of N–Cl groups from surface reaction is superior than that of bulk reaction with maintaining their catalytic activity for decomposition of chemical warfare agents. In order to increase mechanical properties of nanofiber web, amount of hydantoin groups on surfaces has been controlled by blending of normal TPU with azide TPU, and blended nanofiber web maintains their inherent flexibility after hydantoin functionalization and N-chlorination. Optimized blending conditions to achieve both of high N–Cl stability and enhanced catalytic activity have been traced. Surface rich N–Cl groups show better stability with maintaining their inherent catalytic activities.

Ultraviolet (UV) laser irradiation was applied to decontaminate chemical warfare agent simulants chloroethyl phenyl sulfide (CEPS) and malathion, with results obtained from gas chromatography–mass spectrometry analysis. Exposure of CEPS to a 266 nm laser exhibited feasible decontamination by dominantly producing the byproduct diphenyl disulfide. However, decontamination in the cases with 355 and 532 nm exposure on CEPS as well as 266 nm exposure on malathion were relatively inefficient. Results also show a strong correlation between decontamination efficiency and absorption probability, which indicates the importance of selecting proper laser wavelengths and supports the photochemical mechanism of UV laser decontamination.

Bacterial wilt and grey mould in tomato plants are economically destructive bacterial and fungal diseases caused by Ralstonia solanacearum and Botrytis cinerea, respectively. Various approaches including chemical and biological controls have been attempted to arrest the tomato diseases so far. In this study, in vitro growths of bacterial R. solanacearum and fungal B. cinerea were evaluated using four different vitamins including thiamine (vitamin B1), niacin (vitamin B3), pyridoxine (vitamin B6), and menadione (vitamin K3). In planta efficacies of the four vitamin treatments on tomato protection against both diseases were also demonstrated. All four vitamins showed different in vitro antibacterial activities against R. solanacearum in dose-dependent manners. However, treatment with 2 mM thiamine was only effective in reducing bacterial wilt of detached tomato leaves without phytotoxicity under lower disease pressure (106 colony-forming unit [cfu]/ml). Treatment with the vitamins also differentially reduced in vitro conidial germination and mycelial growth of B. cinerea. The four vitamins slightly reduced the conidial germination, and thiamine, pyridoxine and menadione inhibited the mycelial growth of B. cinerea. Menadione began to drastically suppress the conidial germination and mycelial growth by 5 and 0.5 mM, respectively. Grey mould symptoms on the inoculated tomato leaves were significantly reduced by pyridoxine and menadione pretreatments one day prior to the fungal challenge inoculation. These findings suggest that disease-specific vitamin treatment will be integrated for eco-friendly management of tomato bacterial wilt and grey mould.

Flow velocity profiles can be transformed using non-uniform resistance elements, and the design equation for the distribution of pores in a single baffle plate of uniform thickness was formulated to transform any flow velocity profile into another arbitrary velocity profile. The proposed equation was validated first through numerical analysis for a couple of velocity profiles with satisfactory results, and then verified by an experiment with an excellent agreement of maximum difference less than 4.3%. Also found was an empirical relation between the number of holes in the baffle and the accuracy of the transformed velocity profile.

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. OmniBlock modified the surface of the cotton fibers, creating a rough, high surface area uniform coating with many micro-crevasses. As a result, n-dodecane, water, and CWAs beaded up without wetting the surface, exhibiting large contact angles of 154° for water and 121° for n-dodecane, with a small shedding angle of 5° and contact angle hysteresis of 3.2° for water. The designed coating showed excellent liquid repellence properties against three types of CWAs: 129°, 72°, and 87° for sulfur mustard (HD), soman (GD), and VX nerve agents, respectively. Furthermore, OmniBlock coating shows good mechanical properties under tensile strength and wash tests. This remarkable ability to repel CWAs is likely to have potential military applications in personal protective equipment systems requiring self-cleaning functions.

Designing military screen (display) is not complicated in the past, the design should contains easiness of using, visibility and functionality. And it is important that contains all of the information what the system could be gotten. Today military display design can be valued by consideration of human’s cognition model. A few information, which operators of military display could easily miss, could bring critical loss. So the military display needs the ability to help operator decide the military decision with sufficient consideration of battlefield information in a short time. The information is considerably complicated because it has many military entities and many attributes for each entities. For this reason this research contains the methodology of information organization especially for visual information. When the operator use military display, the required information should be recognized at a glance and located where the operator can place his eye easily. Therefore, the display screen should efficiently organize and effectively transfer the information. This paper specifically proposes design methodology to effectively organize and visualize the information in the display screen. The theory of information visualization in a variety of fields already exist, but it has no established theory for the origin of the display screen design. Since the theory was selected to organize the military display interface design for the display screen of the battlefield situation existing information visualization theory.

This thesis paper is a brief summary of user centered design, (particularly in the situation of under the battlefield), which incorporates the related information after reviewing many other papers. A display screen user requires an ability to provide proper information while considering a variety of information in a short period. While operating the display screen, the user is heavily pressed for time as the missions are allocated through many different steps of orders. In addition, since a failure would cause fatal damage or cause further defeat, this increases the pressure of time. The right environment for operating a display screen is most useful when the user is in the most vulnerable time period or long-term continuous operation of the display screen. In that kind of sterile environment, the operating display screen is there to help the user’s decisions for the matter at hand, in this it should follow the user centered design and improve the user’s handiness and use. Furthermore, the information should be provided in accordance with the user's informational and perceptional process, and the capacity of the information process should be improved with the movement through each process and step. This thesis paper can be used as a reference material when designing the display screen in order to apply a user’s experiences.

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. In vitro conidial germination was most drastically inhibited by vapour treatments with carvacrol, cinnamon oil, trans-cinnamaldehyde, citral, p-cymene and linalool. Inhibition of the mycelial growth by indirect vapour treatment with essential oils was also demonstrated compared with untreated control. Carvacrol, cinnamon oil, trans-cinnamaldehyde, citral and eugenol were among the most inhibitory plant essential oils by the indirect antifungal efficacies. Plant protection efficacies of the plant essential oils were demonstrated by reduced lesion diameter on the C. gloeosporioides-inoculated immature green pepper fruits compared to the inoculated control fruits without any plant essential oil treatment. In planta test showed that all plant essential oils tested in this study demonstrated plant protection efficacies against pepper fruit anthracnose with similar levels. Thus, application of different plant essential oils can be used for eco-friendly disease management of anthracnose during pepper fruit production.

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.

Thermal radiation from high-energy emission event, such as nuclear explosion, is characterized by a wide energetic spectrum in air. Black body assumption for the fireball associated with this radiation serves as a reasonable approximation for interpreting the thermal radiation emission characteristics. In this study, the time-integrated thermal flux received by a target on the ground and facing a nuclear burst, was calculated as a function of yield, burst elevation, ground range, and visibility. Results of our calculations were compared with previously reported results for different conditions.

The importance of the aircraft is increasing gradually; among them it may be called Ground Control Station (GCS) receiving the highest expectations. In aspect of operation, operator’s workload and working speed are one of the most important factors. Thus, we need to compare Touch mode and Non Touch mode in order to improve workload and working speed. In this paper, we analyzed the differences of Touch mode and Non Touch mode about workload, working speed in operation of aircraft. Through NASA-TLX and Measured working time, quantified data were collected and an analysis of variance (ANOVA) was performed. According to experimental result, working speed and workload according to input mode showed significant difference. In ground operation, Touch mode is better than Non Touch mode about working speed and workload. In the Touch mode, the optimal value of lower display angle was selected as 60。 angle.

The conditions required for a flow resistance element to uniformize a non-uniform flow in a two-dimensional channel were derived in terms of a non-uniform porosity profile. The validity of this approach was confirmed through a numerical analysis over a wide range of parameter conditions. The proposed equation for the non-uniform porosity distribution gave satisfactory results for a wide variety of velocity profiles at the channel inlet. For sufficiently thick orifices, the equation was valid over a wide range of average porosities, from 0.3 to 0.6. For thin orifices, satisfactory uniformity was obtained only for a mean effective porosity over a narrow range of 0.42–0.48. Two different methods of generating variable porosity, using a constant hole size plus variable blocking plates or using a constant blocking plate size plus variable holes, did not show any appreciable difference in results.

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. The plasma fabric is flexible and lightweight, and it can be scaled up for larger areas, making it attractive for wearable APP applications. Here, we report the various plasma properties of the WAPP device and successful test results showing the decontamination of toxic chemical warfare agents, namely, mustard (HD), soman (GD), and nerve (VX) agents.