Gaseous Elements Research Articles

Assessment of the activity concentration of radon and its health hazard in surface water around the Rooppur Nuclear Power Plant (RNPP) site, Bangladesh

ABSTRACT Radon is a colourless, unscented, radioactive inert gas. As a gaseous element, Rn-222 can be effectively breathed in, leading to a health hazard. The main objective of this study is to measure the amount of Rn-222 concentration in surface water and its associated health hazards around the Rooppur Nuclear Power Plant (RNPP) construction site area in Bangladesh. Twenty water samples were collected each year (2022 and 2023) from different specific locations of the Padma River and investigated for radon concentration through a Durridge RAD7 detector with RAD H2O accessories. The range of radon activity in surface water measured from 0.070 ± 0.035 to 0.385 ± 0.211 BqL−1 with a mean activity of 0.194 ± 0.114 BqL−1 in the year 2022 and in the year 2023, the range of radon activity in surface water measured from 0.035 ± 0.070 to 0.455 ± 0.239 BqL−1 with an average activity of 0.228 ± 0.140 BqL−1. All the radon concentration results were below the recommended limits of WHO (100 BqL−1) and USEPA (11.1 BqL−1). The ranges of annual effective dose (AED) were from 0.1911 to 1.051 µSvy−1 and from 0.095 to 1.242 µSvy−1 in the years 2022 and 2023, respectively, which were lower than the AED recommended by WHO (0.1 mSvy−1). The mean values of excess lifetime cancer risk are 0.0021 × 10−3 and 0.0025 × 10−3 in the years 2022 and 2023, respectively, which were lower than the average standard value recommended by UNSCEAR (0.29 × 10−3). The result of this investigation can be applied as baseline data for radon concentration measurement in the under-construction nuclear power plant site area vicinity of Bangladesh.

Assessment of Levels and Health Risks of Atmospheric Particulate Matter (PM10) and Associated Gaseous Elements in Selected Locations in Lagos, Nigeria

Assessment of Levels and Health Risks of Atmospheric Particulate Matter (PM10) and Associated Gaseous Elements in Selected Locations in Lagos, Nigeria

Research and development activities to increase the performance of the CAPRICE ECRIS at GSI

At GSI the CAPRICE ECRIS is in operation to deliver high charge state ion beams from gaseous and metallic elements to the accelerator facility. A test campaign has been carried out at the ECR test bench to fulfill the demand for higher intensity and stability of high charge state ions and for mixed ion beams. The ion beam stability has been monitored by an Optical Emission Spectrometer (OES), which has been already used to check the plasma and the temperature of the resistively heated oven during metal ion beam operation, particularly for Ca ion beams. During the test campaign, it was investigated that the OES can be used for monitoring the stability of ion beams from gaseous elements and mixed ion beams, and the main achieved results are reported. The ion beams extracted from the ECRIS have been simulated with a particle tracking code in order to study and improve the beam matching into the RFQ. The preliminary results of the study together with possible modifications of the extraction column are presented.

A reaction cell as a sample introduction portal for detection of gaseous components in ICP-MS

The detection of gaseous elements (He, Ne, Kr, and Xe) and molecules (CO2, CH4, and NH3) using inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) is described.

Declines of gaseous element mercury concentrations at an urban site in eastern China caused by reductions of anthropogenic emission

Long-term observations (June 2014 to June 2022) of atmospheric mercury (Hg) mass concentrations were conducted at an urban site in Nanjing, eastern China, together with other air pollutants. Throughout the sampling period, gaseous elemental mercury (GEM) exhibited a substantial decline from 5.41 ± 1.49 ng m−3 in 2014 to 2.17 ± 1.26 ng m−3 in 2022. The monthly mean concentrations of GEM displayed a significant downward trend, with a rate of 0.36 ng m−3 yr−1 (−7% yr−1). To identify the potential sources contributing to the observed GEM levels, positive matrix factorization (PMF) analysis was employed in conjunction with other relevant pollutants. The results revealed that the natural and anthropogenic emissions played comparable roles in shaping the measured GEM concentrations, with the reduction of coal combustion emissions being the primary driver behind the observed declines at this site. Furthermore, GEOS-Chem simulations suggested a substantial reduction of anthropogenic emissions in eastern China in recent years. This study highlights the decreasing trend of GEM concentrations in eastern China over the past decade, which is attributed to the combined efforts in air pollutant controls, resulting in the synergistic mitigation of Hg from the atmosphere.

Mapping of Carbon Dioxide (Co2) Emissions Due To Increased Vehicle Volume in Mataram City

The high level of population and activities in the city of Mataram also increases the use of vehicles as a secondary need for the community to help with daily activities in land transportation. As the use of vehicles increases, the demand for fuel oil (BBM) also increases. Fuel is a material that can be converted into energy by burning fuel where the fuel contains heat energy that can be released and manipulated. Vehicle emissions are a major source of pollution in big cities in Indonesia. CO2 is a compound consisting of the elements carbon and oxygen with the writing CO2. Carbon dioxide is a gaseous element that exists at atmospheric temperature and pressure. The hope for this research is to determine CO2 levels in the city of Mataram and prevent CO2 emissions from increasing. The results of calculating the highest vehicle volume are located in segment III Jalan Majapahit of 3506 pcu/hour which occurs at 17:00 - 17:15 WITA. The results of the regression analysis between vehicle volume as the X variable and CO2 gas emissions as the Y variable on the five road segments conducted by the study were y = 134.57 ln(x) - 970.14 with an R2 value of 0.8661 included in the 0.80 interval – 1,000 which means that the strength of the relationship between vehicle volume and CO2 emissions has a very strong relationship and vehicle volume contributes 86.6165% to CO2 emissions. Based on the results of the discussion that was carried out, the CO2 gas emission levels in all road segments carried out had an average CO2 gas emission level value of 103.31 – 108.56 kg/hour.

STUDY ON THE DISPOSAL OF WASTE FROM THE HYDROGEN GENERATION BY ALUMINUM OXIDATION IN ALKALINE SOLUTION

In face of the current high energy consumption and demand worldwide, a change to a sustainable energy matrix became one of the pillars for global sustainability. The use of renewable energy has been one of the most attractive subjects in recent years. Several public policies in this matter have been suggested and there are ongoing efforts toward their implementation. The United Nations (UN) proposed what is called the 2030 Agenda, which considers 17 Sustainable Development Goals (SDG) to be achieved by the year 2030. In support of the 2030 Agenda, research on the production of fuels from clean and sustainable sources is being conducted by the scientific community around the world. Fossil fuels are finite and also a major source of environmental pollutants, therefore the choice of using renewable sources of energy tends to be an increasingly growing and attractive alternative. Hydrogen is a fuel with a high heating value and is known as the most abundant gaseous element and simplest in chemical structure. The scientific community researching fuel cells has given much attention to the generation and storage of hydrogen. Besides the electrolytic hydrogen production and the reforming of fossil fuels (e.g., natural gas), hydrogen can be generated by metallic means, for example, by oxidation of aluminum in an alkaline solution. The use of recyclable metals, such as aluminum in this study, is an option for sustainable hydrogen generation processes. Nevertheless, like any chemical reaction, part of the products generated are waste, and some are even harmful to the environment, which makes the production of sustainable fuels unfeasible in case of not finding an appropriate technological industrial destination for such waste. The herein study comprises the investigation of the industrial and technological applications of the products of the hydrogen generation reaction from aluminum. Mastering the chemical reaction parameters of that reaction is paramount for the optimal design of a hydrogen generation system. The disposal of the waste is relevant since it makes the energy supply chain complete and sustainable.

A series of plasma innovation technologies by the double glow discharge phenomenon

In order to break the limitation of plasma nitriding technology, which can only be applied to a few non-metallic gaseous elements, the “double glow discharge phenomenon” was defined and then the “double glow plasma surface metallurgy technology” was invented. This double glow plasma surface metallurgy technology can use any element of the Periodic Table for surface alloying of metallic materials. Countless surface alloys with special physical and chemical properties have been produced on the surfaces of conductive materials. By using the double glow discharge phenomenon, a series of new double glow plasma technologies have been developed to apply to surface metallurgy, graphene technology, brazing, sintering, arc plasma surface alloying, nanotechnology, cleaning, carburizing without hydrogen, and so on. This article briefly introduces the basic principles, functions, and characteristics of each technology. The application prospects and development directions of plasma in metallic materials and the machinery manufacturing industry will also be discussed.

Exotic Inverse Kinetic Isotopic Effect in the Thermal Decomposition of Levitated Aluminum Iodate Hexahydrate Particles

Aluminum iodate hexahydrate ([Al(H2O)6](IO3)3(HIO3)2; AIH) represents a novel, oxidizing material for energetic applications. Recently, AIH was synthesized to replace the aluminum oxide passivation layer of aluminum nanoenergetic materials (ALNEM). The design of reactive coatings for ALNEM-doped hydrocarbon fuels in propulsion systems requires fundamental insights of the elementary steps of the decomposition of AIH. Here, through the levitation of single AIH particles in an ultrasonic field, we reveal a three-stage decomposition mechanism initiated by loss of water (H2O) accompanied by an unconventional inverse isotopic effect and ultimate breakdown of AIH into gaseous elements (iodine and oxygen). Hence, AIH coating on aluminum nanoparticles replacing the oxide layer would provide a critical supply of oxygen in direct contact with the metal surface thus enhancing reactivity and reducing ignition delays, further eliminating decades-old obstacles of passivation layers on nanoenergetic materials. These findings demonstrate the potential of AIH to aid in the development of next-generation propulsion systems.

Osteomyelitis of the Lower Limb: Diagnostic Accuracy of Dual-Energy CT versus MRI.

MRI is the preferred imaging technique for the identification of osteomyelitis. The key element for diagnosis is the presence of bone marrow edema (BME). Dual-energy CT (DECT) is an alternative tool which is able to identify BME in the lower limb. To compare the diagnostic performance of DECT and MRI for osteomyelitis, using clinical, microbiological, and imaging data as reference standards. This prospective single-center study enrolled consecutive patients with suspected bone infections undergoing DECT and MRI imaging from December 2020 to June 2022. Four blinded radiologists with various experience levels (range of 3-21 years) evaluated the imaging findings. Osteomyelitis was diagnosed in the presence of BMEs, abscesses, sinus tracts, bone reabsorption, or gaseous elements. The sensitivity, specificity, and AUC values of each method were determined and compared using a multi-reader multi-case analysis. A p value < 0.05 was considered significant. In total, 44 study participants (mean age 62.5 years ± 16.5 [SD], 32 men) were evaluated. Osteomyelitis was diagnosed in 32 participants. For the MRI, the mean sensitivity and specificity were 89.1% and 87.5%, while for the DECT they were 89.0% and 72.9%, respectively. The DECT demonstrated a good diagnostic performance (AUC = 0.88), compared with the MRI (AUC = 0.92) (p = 0.12). When considering each imaging finding alone, the best accuracy was achieved by considering BME (AUC for DECT 0.85 versus AUC of MRI of 0.93, with p = 0.07), followed by the presence of bone erosions (AUC 0.77 for DECT and 0.53 for MRI, with p = 0.02). The inter-reader agreement of the DECT (k = 88) was similar to that of the MRI (k = 90). Dual-energy CT demonstrated a good diagnostic performance in detecting osteomyelitis.

Deterioration of Fisheries and Improvement Procedure of Fisheries: the Improvement Procedure of Inland and Marine Fisheries throughout the World

Deterioration of Fisheries and Improvement Procedure of Fisheries: the Improvement Procedure of Inland and Marine Fisheries throughout the World

Effect of addition of calcium-based reagents on defect reduction of cast Fe-Ni-Cr alloy

ABSTRACT UNS N08120, a member of Fe-Ni-Cr alloy family, is capable to withstand severe high temperature and corrosive environments for applications in chemical, power, waste processing etc. Precautionary measures during the casting process can result in sound casting. For the production of UNS N08120 via casting route, the most common method is the vacuum induction melting process, which is less affordable option for small-scale production. Gaseous elements and impurities may get entrapped during casting. The aim of current research is to produce UNS N08120 alloy sound castings using non-vacuum-based induction melting by adding calcium-based reagents and perform a comparative study. This research uses a novel method to reduce the chances of generation of defects that are caused due to the presence of impurities. Two combinations of chemical-based reagents like CaC2, CaO and CaF2 have been selected and used during the sand-casting process. These identified reagents react with the gases and impurities that exist in the molten alloy, and deplete them. The resulting castings yielded alloy free from microstructural defects. This method has been found effective for removal of unwanted gases and impurities in an easy manner. CaF2 addition also plays vital role in degassing phenomenon of UNS N08120.

The effect of indoor environmental quality on the productivity of factory workers: A case of pharmaceutical factories in Southwest Nigeria

The indoor environment of pharmaceutical factory building is known to be a very active place with industrial equipment, machineries, full of light, noise, particulate matter, and other gaseous elements. Having this all-in-one place can be a challenge to the wellbeing and possibly the productivity of the workers of the factory. As a result, the study investigated the effect of indoor environmental quality (IEQ) on the productivity of the pharmaceutical factory workers. This review of relevant literature from e-books, articles, conference proceedings, technical reports, textbooks, thesis and periodicals was conducted between 2010-2022. 14 pharmaceutical factories were investigated within 13 months (October 2020-November 2021). The factors of indoor environmental quality influencing workers’ wellbeing as well as their productivity, were thoroughly investigated using a strategic procedure. It was discovered that the factors involved in a pharmaceutical factory building's IEQ and the productivity factors of the workers were complex and diverse. This paper concludes that the previous studies reviewed do not show that indoor environmental quality of PFB have any significant impact on the productivity of the pharmaceutical factory workers.

An analysis of the level of vehicular emission in Kaduna Metropolis

Vehicular emissions are one of the major sources of air pollution in urban centres due to the use of petrol and diesel fuels. This study analysed the level of vehicular emissions in Kaduna Metropolis. A longitudinal research design was used. Data were acquired on the Road Network of Kaduna Metropolis, level of concentration of gases, Statistics of the motor vehicles movement at each sampling point, type of vehicle, make, age and the fuel used. Copies of the relevant questionnaire were distributed at eleven established sampling points (parks). Gaseous elements examined included Carbon Monoxide (CO), Volatile Organic Compound (VOC), Nitric Oxide (NO2), Hydrogen Sulphite (H2S) and Sulphur Dioxide (SO2). The concentration of CO exceeded the accepted safe limits especially at morning peak periods. Toyota Liteace was the most used commercial vehicle; 74% of these vehicles are propelled by petrol fuel. Not less than 91% of drivers of such vehicles suffer from illnesses due to the polluted air at least once a month. Regular maintenance of commercial vehicles and awareness campaigns are suggested as measures to mitigate vehicular emissions. Government should establish a reliable and efficient mass transit system to reduce the number of individual vehicles and motorcycles on roads thus, reducing harmful emissions.

Improved atmospheric mercury simulation using updated gas-particle partition and organic aerosol concentrations

The gaseous or particulate forms of divalent mercury (HgII) significantly impact the spatial distribution of atmospheric mercury concentration and deposition flux (FLX). In the new nested-grid GEOS-Chem model, we try to modify the HgII gas-particle partitioning relationship with synchronous and hourly observations at four sites in China. Observations of gaseous oxidized Hg (GOM), particulate-bound Hg (PBM), and PM2.5 were used to derive an empirical gas-particle partitioning coefficient as a function of temperature (T) and organic aerosol (OA) concentrations under different relative humidity (RH). Results showed that with increasing RH, the dominant process of HgII gas-particle partitioning changed from physical adsorption to chemical desorption. And the dominant factor of HgII gas-particle partitioning changed from T to OA concentrations. We thus improved the simulated OA concentration field by introducing intermediate-volatility and semi-volatile organic compounds (I/SVOCs) emission inventory into the model framework and refining the volatile distributions of I/SVOCs according to new filed tests in the recent literatures. Finally, normalized mean biases (NMBs) of monthly gaseous element mercury (GEM), GOM, PBM, WFLX were reduced from −33%–29%, 95%–300%, 64%–261%, 117%–122% to −13%–0%, −20%–80%, −31%–50%, −17%–23%. The improved model explains 69%–98% of the observed atmospheric Hg decrease during 2013–2020 and can serve as a useful tool to evaluate the effectiveness of the Minamata Convention on Mercury.

Design and first operations of a ECR based He source at INFN-LNS

A new source for the TANDEM accelerator of LNS has been designed and installed. It is called NESTOR (Noble Elements Source for acceleraTORs) and consists of an ultra-compact ECR microwave discharge type ion source [1] operating around 6 GHz and up to 40 W of RF power, provided by a solid state power amplifier, coupled to a Li-Charge Exchange Cell (Li-CEC). It is engineered for the production of a wide range of 1+ and/or 1- ion beams from gaseous elements, in particular for noble gases. This work presents the characterization of the primary source and first operations of the whole setup on the HV platform (injector) of the Tandem. The He+ beams have been formerly characterized in terms of current, beam shape (by BaF2 beam viewers) and emittance (by the three-gradients method). Measurements have been carried out varying pressure, microwave frequency and RF power. Then, the source has been moved to the HV platform, coupled to the Li-CEC for first operations running in gas-exchange mode. Activities are ongoing to optimize beam transport towards the Tandem.

The cohesive entropy of condensed materials, empirical relations and restrictions

Entropy factors of a material are connected through an equation which relates three independent experimental values specific to each material: ΔfS=S-∑inSatoms,i. (Note: our results refer to independently summed ∑1nSatoms,i values rather than calculation by simple difference of the third dependent value from the other two of these values.) We define the cohesive entropy coefficient, αScoh, through ΔfS=α∑inSatoms,i.Having ready access to a large database of thermodynamic data for solid ionic materials from earlier studies, we have investigated the generalisations that may be made among these entropy quantities for this group of materials.We find that the data points of this three-dimensional system are confined to a fan-shaped tilted plane which has rather strict lateral limits, with the upper limits controlled by the entropies of gaseous elements and the lower limits by the entropies of solid elements. This has the consequence of providing insight into the understanding of entropy values and their limits as a check on experimental determinations. In particular, formation and standard entropies for condensed phases are shown to be proportional to one another with a fixed proportionality constant, the cohesive entropy coefficient, αScoh = -0.831.Evidence is provided that the same restrictions apply to condensed organic materials, and we suggest that these entropy relations are applicable to condensed materials in general.

Obstructive sleep apnoea patients vs laryngopharyngeal reflux disease: Non-invasive evaluation with NBI and pepsin detection in tears.

Obstructive sleep apnea (OSA) and laryngopharyngeal reflux disease (LPR) are two common diseases that lower patients’ quality of life. OSA is defined by cyclic events of airflow obstruction that occurs during sleep, while LPR is characterized by upper airway inflammatory signs and symptoms due to the return of gastroduodenal gaseous and liquid elements. pH-metry is the gold standard in LPR diagnosis, but considering its invasiveness among other negative traits, questionnaires that catalog symptoms and signs of the disease such as reflux symptom index (RSI) and reflux finding score (RFS) are preferred. Moreover, LPR can be evaluated by testing the presence of pepsin in tears, and narrowband imaging (NBI) has been introduced for the early diagnosis of larynx oncological disease. This paper aims to test whether LPR is more frequent in OSA patients than in control ones, performing a non-invasive protocol composed of RSI and RFS test (with light vs. NBI techniques) followed by pepsin detection in tears. Sixty-eight LPR patients were enrolled in the study (45 with OSA and 23 without OSA). A strong linear relationship between apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) was found, and patients who presented pepsin in tears had higher values of AHI and ODI in comparison to patients without it. Pathological RFS and NBI showed higher values of AHI and ODI in comparison to the control group. Furthermore, pathological RSI showed higher values of AHI and ODI in comparison to the control group. In conclusion, this diagnostic combined non-invasive protocol may be a good method to perform an early diagnosis of LPR.

Improved removal of selenium by calcite-derived CaO with porosity and anti-sintering in presence of acid gas

Ca-based sorbent injected into furnace is a promising technology for control emission of selenium. As commercially available CaO was easy to sintering under actual furnace temperature or in presence of CO2/SO2, calcite-derived CaO on removal of Se were tested by a gas-solid reaction system, which was designed to simulate process of gaseous trace elements in flue gas fast contacting with injected minerals, showing a simple, economical and practical method to improve anti-sintering. Results showed conspicuous superiority of calcite-derived CaO for its porosity and anti-sintering. Capture efficiency at 700–800 °C could reach to 80% basically, even to 90% as maximum, and chemisorption was dominance for capture by analysis of thermal desorption. Both CO2 and SO2 could affect capture, while their effects mechanisms on Se capture were quite different. The impact of CO2 depended on the adsorption temperature. Below 700 °C, existence of CO2 could inhibit Se capture due to formed CaCO3, so Se capture was suggested at above 700 °C after considering both capture efficiency and leachability. Effects of SO2 was relevant to content of CaSO4 formed. Se retention was promoted as low content of CaSO4 formed, but capture was inhibited by thickened product layer as high content formed.

Study on Defect Reduction in Casting of Ni-Cr alloy (UNS N06003)

In modern times, selection criteria of materials are solely based on its utilization. The characteristics of materials like high temperature sustainability with regard to its strength and corrosion resistance is the primary requirement to satisfy its operations. Industries categorised in sectors like energy, manufacturing, electronics etc. greatly rely on input materials and their purity decides their performance. Amongst many developed alloys, nickel-based alloys find their position in applications having temperatures from cryo to nuclear ranges. One of such unique materials, being used from minute components of semiconductor industry to huge components of marine industry is UNS N06003. It is basically Ni-Cr based alloy having greater than three-fourth fraction of nickel. For major applications wrought material is widely used, but cast material marks their positions in selected applications. This paper deals with casting of UNS N06003 and improving its quality. The reasons associated with cast defects and drawbacks of defects in terms of performance have been discussed. To minimize casting defects and produce a sound casting, this research adopts a novel approach of removal of unwanted gaseous elements. In degassing stage, molten metal is introduced with the combination of calcium-based fluxes which mainly remove the entrapped gases and lighter impurities in the form of slag. It has been found that the addition of quicklime (CaO) in combination with calcium carbide (CaC2) resulted in reduction of gaseous elements like nitrogen, phosphorus and sulphur. Up to 33% reduction of gaseous elements has been detected.