Health concerns related to particulate matter (PM) pollution are on the rise globally. This study investigates the effects of the main components of PM on human airway epithelial cells (Calu-3), focusing on three distinct types: PM10-bound PAHs (including Benzo[a]anthracene and Benzo[b]fluoranthene), PM10-bound trace elements (containing arsenic and lead), and PM2.5-bound ions (comprising sodium and calcium). Calu-3 cells were exposed to these PM components at concentrations ranging from 2 to 100 μg/mL. Unexposed Calu-3 cells exhibited a 60% increase in metabolic activity after 12 hours. In contrast, exposure to PM components resulted in significant reductions in cell viability, with PM10-bound PAHs and PM10-bound trace elements causing decreases of 54% and 55% respectively, and PM2.5-bound ions leading to a 63% reduction at 100 μg/mL. Additionally, there was found to be a notable rise in the expression of proinflammatory cytokines IL-8 and TNF-α. Specifically, IL-8 levels increased by 456%, and TNF-α levels rose by 660% after 12 hours of exposure to PM2.5-bound ions. These findings indicate that the size and composition of fine dust particles play a critical role in their cytotoxic effects, contributing to increased cell death, membrane damage, and necrosis in airway epithelial cells.

Zeolitic imidazolate frameworks (ZIFs) along with carbon nanofibers and polyaniline composite have been explored as an electrochemical sensing platform in nitrite measurement at trace level. Owing to their topology, high surface area and porous structure, these metal–organic frameworks (MOFs) find widespread utility in different application domains. Nitrites are widely used as preservatives in dairy, meat products, and packaged food stuffs. They form N-nitrosamines, which are potential carcinogens and cause detrimental health effects. These ZIF-based MOFs along with carbon nanofibers and polyaniline have emerged as an efficient electrochemical sensing material. The composite has been characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and BET surface area studies. The electrochemical performance of the composite has been evaluated by forming as a thin film of composite on the surface of glassy carbon electrode and studying its impedance as well as electrochemical sensing behavior. The sensor exhibited good analytical response in nitrite measurement with a limit of detection of 8.1 μM. The developed sensing platform has been successfully applied to quantify the nitrite levels from water samples. The results obtained are in good agreement with the results of standard protocol.

To improve the safety of nuclear fuel, research on the advanced nuclear fuel (UO2) by adding various trace elements is being conducted. For example, the addition of metals such as Mo, Cr can improve the thermal conductivity of nuclear fuel, minimizing the diffusion of fission products. Trace metal oxide additives (SiO2, Cr2O3, Al2O3, etc.) can suppress the release of fission gases. In general, complete dissolution of the fuel sample is required for chemical analysis to determine its elemental compositions. Among widely used metal oxide additives, aluminum oxide is difficult to dissolve in nitric acid due to its excellent thermal and chemical stability. In this study, we investigated on different chemical dissolution methods by applying a microwave digestion system under various acid solutions. We confirmed the validity of the digestion method by carrying out trace element analysis using an Inductively-Coupled Plasma Atomic Emission Spectrometer (ICP-AES).

Adsorption of arsenic by graphene-based adsorbents is widely applied to remove arsenic from water and has become a promising technology. However, most of the reported studies were conducted at a relatively higher concentration of arsenic in As (V) oxidative form, whereas the As (III) is more difficult to remove from water and more toxic, which prompted us to conduct the study at a lower concentration of 1 ppm in As (III). A Facile and controlled synthesis of graphene-based metal/ metal oxide nanomaterials and adsorptive removal of aqueous As (III) is reported here. Adsorbents were characterized using spectroscopy (FTIR, XPS and Raman) and microscopy (TEM). The maximum uptake of arsenic obtained was 88.8% from the RGO-Fe3O4 composite among all the adsorbents. The pseudo-second-order model and Intra-particle mass transfer diffusion model were applied to determine the adsorption kinetics with varying contact time between the adsorbents and the As (III) in water to interact. Experimental results suggest that the adsorption of As (III) onto the adsorbents was a multi-step process involving external adsorption to the surface followed by diffusion to the interior. A simple spectrophotometric method also was used for the detection and quantification of As (III).

The segmentation of activated components including reactor vessel and reactor vessel internals requires many information. The primary information is material composition, trace materials in the composition, neutron flux during operation, etc. According to the EPRI report the primary basis of activity in a decommissioning source term is the activated metals from the reactor vessel and vessel internal components. The report indicates that over 95% of the radioactivity from decommissioning, except from spent nuclear fuel, consists of activated metals. These are from the reactor vessel, reactor internal structures and expendable components which are constructed primarily of various grades of stainless steel. Stainless steel contains appreciable levels of impurity cobalt. The common primary radionuclides of concern for the disposal environment from activated metals identified in US and international studies include C-14, Cl-36, Ni-59, Co-60, Ni-63, etc. The most common types of stainless steels used in reactor vessel construction and internal components include the Type 304(L), Type 316(L) and various grades of Inconel. The components of stainless steel are mainly Ni, Cr, Mo, Nb, etc., and when these elements are activated, they produce nuclides such as Nb-94, Tc-99, Sr-90, etc. In this study, the current status of activation analysis is reviewed to understand the effects of many variables. Also, the effect of trace materials is reviewed, including transformation of radioactive nuclides.

Herein, a new and generic strategy has been proposed to introduce uniformly distributed graphitic carbon into the nanostructured metal oxide. A facile and generic synthetic protocol has been proposed to introduce uniformly distributed conducting graphitic carbon into the Co3O4 nanoparticles ( Co3O4 NPs@graphitic carbon). The prepared Co3O4 NPs@graphitic carbon has been drop casted onto the portable screen-printed electrode (SPE) to realize its potential application in the individual and simultaneous quantification of toxic Pb(II) and Cd(II) ions present in aqueous solution. The proposed Co3O4 NPs@graphitic carbon-based electrochemical sensor exhibits a wide linear range from 0 to 120 ppb with limit of detection of 3.2 and 3.5 ppb towards the simultaneous detection of Pb(II) and Cd(II), which falls well below threshold limit prescribed by WHO.

전자 및 화학 산업의 초순수 생산 및 원자력 발전소의 부식 제어를 위해 이온교환 수지탑의 성능 파악이 필수적이다. 따라서 본 연구에서는 4종의 H 및 ETAH 형 양이온 교환수지가 채워진 양이온 및 혼상 이온교환수지탑에 미량의 NaCl를 포함하는 에탄올아민(ETA) 및 암모니아(NH3) 용액을 주입하여 양이온 파과특성을 조사하였다. 조사 결과, 주성분인 ETAH+ 및 NH4 +와 달리, 미량성분인 Na+는 (이론적교환용량의 3배 이상) 시험기간 동안 수지탑 출구에서 파과 및 오버슈팅 현상이 나타나지 않았다. H형 수지탑의 파과현상은 ETAH+ 및 NH4 +가 순서대로 일어났고, 오버슈팅은 NH4 +가 파과할때 ETAH+에 대해서 발생했다. 파과영역의 너비로 결정되는 상대적 선택도는 NH4 +가 ETAH+보다 최대 51.5 % 더 높았다. 유입수 Na+ 농도가 높을수록, 선택도는 감소하고 오버슈팅 현상은 증가하였다. 이온교환 수지의 고유 특성을 개선하여 감소시킬 수 있는 Na+ 누출은, ETAH형에서 높았고 4종의 양이온수지에 대해 동일하지 않은 것으로 조사되었다.

The concentrations of four potentially toxic elements were analyzed in 70 spraint samples of Eurasian otters from the Daechung Lake area. The median concentrations of As, Hg, Ni, and Pb were 1.19, 1.06, 9.95, and 0.37 μg/g dry weight, respectively. A moderate negative correlation was observed between the levels of Hg and Pb (rs = -0.47). The Hg levels showed a weak negative correlation with the distances of the sampling locations from the Daechung Dam (rs = -0.35). This study provides baseline information on the health risks associated with the hazardous elements in otter species.

Moderately diverse, but very abundant trace fossils are found from the Late Pleistocene deposits of Jeju Island, Korea. Vertical I-, Y- and U-shaped domichnia of annelids or decapods are, over 2500, extremely abundant, 3D network domichnia of callianassids are, over 200, very abundant, and small sinuous trails of nematode repichnia are, over 50, abundant in number. Horizontal trails attributable to polychaete or worm-like animals are, less than 50, common, but horizontal spreiten burrows, fish traces and crab trackways are, less than 10, rare in occurrence. Of these trace fossils, Taenidium barretti, Undichna britannica and Undichna unisulca represent the first record from the Pleistocene in Asia. Psilonichnus upsilon is the second record in Asia. Crab trackways probably produced by underwater punting gait of sideway walking crabs may represent the first record in the world. In addition, diverse and very abundant footprints of more than 500 hominids, more than 200 birds and more than 1000 mammals are closely associated with these invertebrate trace fossils. Trace fossil assemblage integrated with sedimentary facies is interpreted to have been formed in the marginal marine foreshore to backshore environment corresponding to the Psilonichnus and Skolithos ichnofacies.