Source Categories Research Articles

Anthropogenic emissions estimated using surface observations and their impacts on PM2.5 source apportionment over the Yangtze River Delta, China

Source-tagged source apportionment (SA) has advantages for quantifying the contribution of various source regions and categories to PM2.5; however, it is highly affected by uncertainty in the emission inventory. In this study, we used a Regional multi-Air Pollutant Assimilation System (RAPAS) to optimize daily SO2, NOx and primary PM2.5 (PPM2.5) emissions in the Yangtze River Delta (YRD) in December 2016 by assimilating hourly in-situ measurements. The CMAQ-ISAM model was implemented with prior and posterior emissions respectively to investigate the impacts of optimizing emissions on PM2.5 SA in the YRD megalopolis (YRDM) and three megacities of Shanghai, Nanjing, and Hangzhou in the YRDM. The results showed that RAPAS significantly improved the simulations and reduced the emission uncertainties of the different pollutants. Compared with prior emissions, the posterior emissions in the YRD decreased by 13% and 11% for SO2 and NOx respectively, and increased by 24% for PPM2.5. Compared with SA using prior emissions, the contributions from Hangzhou, northern Zhejiang, and areas outside of the YRD to the YRDM increased. The local contributions from the YRDM, Nanjing and Shanghai decreased by 1.8%, 9.7%, and 2.3%, respectively, whereas that of Hangzhou increased by 5.6%. The changes in the daily local contributions caused by optimizing emissions ranged from −18.0% to 23.6%. Generally, under stable weather conditions, the local contribution changed the most, whereas under unstable weather conditions, the contribution from upwind areas changed significantly. Overall, with optimized emissions, we found in Nanjing, Shanghai, and Hangzhou, local emissions contributed 18.2%, 39.6% and 36.8% of their PM2.5 concentrations, respectively; long-range transport from outside the YRDM contributed 59.2%, 48.1%, and 48.2%, respectively. This study emphasizes the importance of improving emission estimations for source-tagged SA and provides more reliable SA results for the main cities in the YRD, which will contribute to pollution control in these regions.

Source characterization guidelines for noise mapping of port areas

Maritime transport for both passengers and freight is continuously increasing and, consequently, the global attention toward its sustainability is growing. Ships offer advantages in terms of environmental impact compared to other transportation systems but the increasing traffic volume is expected to increase pollutants. Noise produced in port areas has been neglected for too long, until the INTERREG Maritime programme Italy-France 2014–2020 has brought to light how citizen complaints are emerging for some of the main ports in the Mediterranean. However, port noise prevention and management is difficult as knowledge on specific sources is very limited in the literature. Furthermore, on field measurements are difficult to be performed given the complexity of the port area, where multiple types of sound emitters mix and confuse each other.Noise maps represent the first important step in order to align ports to the requirements set by the Environmental Noise Directive to the transportation infrastructures. Once computed, they are an excellent tool supporting port management towards the reduction of citizens’ noise exposure while ensuring traffic growth.The present paper reports a guideline for the characterization of noise sources needed as inputs for the noise maps, as developed in the framework of the INTERREG Maritime programme Italy-France 2014–2020. On the basis of the current state of the art, a procedure has been elaborated for different categories of noise sources acting in port, ranging from stationary to moving ships, from mooring operations to loading/unloading operations, from industrial activities to road and railway traffic.

Application of an improved gas-constrained source apportionment method using data fused fields: A case study in North Carolina, USA

A number of studies have found differing associations of disease outcomes with PM2.5 components (or species) and sources (e.g., biomass burning, diesel vehicles and gasoline vehicles). Here, a unique method of fusing daily chemical transport model (Community Multiscale Air Quality Modeling) results with observations has been utilized to generate spatiotemporal fields of the concentrations of major gaseous pollutants (CO, NO2, NOx, O3, and SO2), total PM2.5 mass, and speciated PM2.5 (including crustal elements) over North Carolina for 2002–2010. The fused results are then used in chemical mass balance source apportionment model, CMBGC-Iteration, which uses both gas constraint and particulate matter concentrations to quantify source impacts. The method, as applied to North Carolina, quantifies the impacts of ten source categories and provides estimates of source contributions to PM2.5 concentrations. The ten source categories include both primary sources (diesel vehicles, gasoline vehicles, dust, biomass burning, coal-fired power plants and sea salt) and secondary components (ammonium sulfate, ammonium bisulfate, ammonium nitrate and secondary organic carbon). The results show a steady decrease in anthropogenic source impacts, especially from diesel vehicles and coal-fired power plants. Secondary pollutant components accounted for approximately 70% of PM2.5 mass. This study demonstrates an ability to provide spatiotemporal fields of both PM components and source impacts using a chemical transport model fused with observation data, linked to a receptor-based source apportionment method, to develop spatiotemporal fields of multiple pollutants.

An empirical analysis of surface-level methane emission from anthropogenic sources in India

This study presents an empirical analysis of surface-level methane emission from anthropogenic sources in two major Indian cities. Three categories of sources were considered- (1) fossil fuel exploration and energy production (2) agriculture and livestock farming and (3) waste processing and disposal. In each city, specific sources were identified and mapped to the nearest methane monitoring station. As these sources were active for varying periods, treatment and control periods were designed by partitioning the observation period based on the activity of sources. This experimental design framework was used to formulate and test hypotheses on contribution of these sources to methane emission. Given the limitations and statistical properties (non-normal residuals and heteroskedasticity) of the data a robust alternative to classical analysis of variance (ANOVA) was used to test three hypotheses. Tests confirmed that these sources contributed significantly to methane emission. Specifically, emission from MSW disposal facilities was substantial as evident from the data in Delhi. In Bengaluru, aggregate emission from following sources was found significant- (1) a diesel-based power plant and a landfill (2) a sewage treatment plant and a landfill. This empirical work compliments previous studies on greenhouse gas emissions, which were based on climate models and satellite remote sensing data. This analysis of natural experiment ends with recommendations to manage methane emission from anthropogenic sources.

A framework for the rapid assessment of seismic upgrade viability using performance-based earthquake engineering

The performance-based earthquake engineering (PBEE) methodology allows designers to deaggregate expected seismic losses in a building to a component level. This deaggregated information provides the opportunity to tailor upgrade strategies to individual structures based on sources of losses. However, the optimization of an upgrade strategy becomes difficult because of the relationship between a structure and its nonstructural components; hence, multiple competing upgrade options must be considered. To address this obstacle, this article proposes a framework to guide the assessment of the viability of both structural and nonstructural upgrade strategies, while accounting for limited design resources likely encountered in the early stages of the design process. The framework utilizes the median shift probability (MSP) method, a modified version of the PBEE method introduced in this article, to rapidly summarize the effects of structural upgrades on nonstructural components by considering the impacts of structural modifications on the floor hazards. While accounting for this relationship, the MSP method utilizes the deaggregation of loss across different source categories to identify the benefit of combined structural and nonstructural upgrades, increasing a designer’s understanding of the impact of structural upgrades on losses and allowing for the rapid determination of optimized upgrade strategies unique to the owner’s conditions. A case study example of the implementation of the framework is provided, and the results obtained from the MSP method are compared with those obtained from more rigorous but resource-intensive optimization analysis. An implementation of the MSP method in Microsoft Excel is provided with this article.

Career Information Practices of Guidance Practitioners

Although career development theories underline the central role of information in career choice and studies show that guidance practitioners are among the main information sources of people making career choices, the actual information practices of these practitioners in their career interventions remain fragmented. Moreover, the studies on the theme of career choice associating information, information sources and information practices (whether it is among guidance practitioners or individuals in career choice) offer little conceptualization on these notions. In order to fill this gap, an online survey of 330 guidance practitioners in Quebec was conducted to document specifically their career information practices (information sources consulted and categories of career information sought). Statistical analysis show that the main career information sought relates to central elements of career choice (training programs and occupations) and the main information sources consulted are non-human and institutional. In addition, some contextual elements are associated with seeking and selecting certain categories of information and sources. The discussion highlights the importance of digital sources in the information practices of these practitioners, the association between the populations served and the choice of information sources and categories of career information and the role of co-workers as information support on career and beyond.

An analysis of the temporal variability in volatile organic compounds (VOCs) within megacity Seoul and an identification of their sources

In this study, the volume mixing ratio of 55 volatile organic compound (VOC) species was measured every hour using the online TD-GC-FID system during the period from January 2018 to December 2019 in Seoul. The most abundant species were ethane (10.0 ppbv) and toluene (4.1 ppbv), with alkanes and aromatics accounting for 57.5% and 31.5% of the total VOCs (TVOC), respectively. The mixing ratios of the TVOC were markedly higher in July and November, mainly owing to the presence of aromatics and alkanes, respectively, but were lower in other months, without any significant differences in other months. Of the aromatics, the maximum mixing ratios of xylene, benzene, and toluene were observed in summer, winter, and both seasons, respectively. Principal component analysis showed that emissions from traffic and solvent use were the main VOC sources, which were further categorized into liquefied natural gas/liquefied petroleum gas/gasoline, diesel fuel, mixed combustion, industrial solvents, and paint solvents. The two solvent sources were well represented by toluene and xylene, respectively. In addition, the distinct VOC composition of the air masses clustered by the back trajectory reveals the origin, seasonality, and transport characteristic of the five source categories. This study is the first report on multiyear variability of VOC mixing ratios in Seoul that highlights the contribution from evaporation sources and fugitive emissions and the potential impact of intercity transport from industrial areas near Seoul.

Per- and poly-fluoroalkyl substances in sediments from the water-level-fluctuation zone of the Three Gorges Reservoir, China: Contamination characteristics, source apportionment, and mass inventory and loadings

Sixteen paired surface sediment samples (0–5 cm, n = 32) covering upstream to downstream of water-level-fluctuation zone of Three Gorges Reservoir, China were collected in March 2018 (following six months of submergence) and September 2018 (after six months of exposure). Seventeen per- and poly-fluoroalkyl substances (PFASs) were quantified to evaluate contamination characteristics, apportion source categories and estimate mass inventory and loadings. The concentration of ΣPFASs ranged from 0.26 to 0.82 ng·g−1 at high water-level (HWL) and 0.46–1.53 ng·g−1 at low water-level (LWL). Perfluorooctanoic acid (PFOA, mean: 0.32 ng·g−1) and perfluorooctane sulfonate (PFOS, mean: 0.12 ng·g−1) dominated, accounting 44.9% and 16.3% of the total PFASs, respectively. The distribution of PFASs was more influenced by anthropogenic activities than physicochemical parameters of the sediments. Positive matrix factorization (PMF) identified PFOA-based products was the major sources (40.1% and 38.6%, respectively). Besides, the direct sources of PFOA-, PFOS-, PFNA-and PFBA-based products played the predominant role, while the indirect degradation of precursors contributed relatively little. The sediment (0–5 cm) mass inventory of PFASs at LWL (57.5 kg) was higher than HWL (39.3 kg). The annual mass loadings of the total PFASs, PFOA, PFOS, perfluoroundecanoic acid (PFUdA) and perfluorononanoic acid (PFNA) from the upstream to the middle-lower reaches of Yangtze River were 27.4 kg, 11.1 kg, 4.63 kg, 2.89 kg and 2.57 kg, respectively. This study could provide the basic datasets of PFASs in surface sediments of the TGR, and also indicate an important transport of PFASs from upstream to the lower reaches, which should be further studied as well.

Impact of the initial hydrophilic ratio on black carbon aerosols in the Arctic

Black carbon (BC) contributes to patterns of Arctic warming, yet the initial hydrophilic ratio (IHR) of BC emitted from various sources and its impact on Arctic BC remain uncertain. With the use of a tagged tracer method of BC implemented in the global chemistry transport model GEOS-Chem, IHRs were partitioned into 7 BC combustion source categories according to the PKU-BC-v2 emission inventory. The results show that as the IHR increased, the concentration of BC decreased globally. The impact on Arctic BC was mainly reflected in the vertical profile and the burden rather than at the surface. Specifically, the greatest impact of IHR on Arctic BC appeared in summer, with the largest perturbation appearing at an altitude of approximately 600 hPa, reaching 8%. This change in BC vertical profile was mainly caused by the IHR change of wildfire combustion in Russia (44%) and Canada (51%), and the emissions from these two regions were also the two most important contributors to the BC concentration and burden in the middle and lower Arctic atmosphere in summer. In the other three seasons, anthropogenic combustion sources (oil, coal, and biomass) in East Asia, Russia, and Europe accounted for 19–40%, 14–28%, and 7–23%, respectively, of the monthly BC burden. Emissions from Russia were the most important contributor (27–43%) to the monthly BC surface concentration. Due to the large adjustment in IHR from 20% to 70%, biomass burning in Europe was shown to be the dominant contributor causing both burden (39%) and surface concentration (88%) changes in all seasons except summer.

Internet Search Results for Older Adult Physical Activity Guidelines: Scoping Review.

BackgroundOlder adults seek health-related information through casual internet searches. Yet, researchers focus on peer-reviewed journals and conference presentations as primary dissemination strategies. Representatives of mass media are alerted (passive diffusion) of new studies or recommendations, but the veracity of the information shared is not often analyzed, and when it is, the analysis is often not comprehensive. However, most older adults do not have access to peer-reviewed journal articles or paid subscription services for more reputable media outlets.ObjectiveWe aimed to determine what information was readily available (ie, open access) to older adults who may casually search the internet for physical activity recommendations.MethodsWe performed a 6-part scoping review to determine the research question and available evidence, and extract data within open-access top hits using popular online search engines. Results were categorized by a dissemination model that has categories of sources, channels, audience, and messages.ResultsAfter the iterative search process, 92 unique articles were included and coded. Only 5 (5%) cited physical activity guidelines, and most were coded as promoting healthy aging (82/92, 89%) and positive framing (84/92, 91%). Most articles were posed as educational, but the authors’ credentials were rarely reported (ie, 22% of the time). Muscle strengthening and balance components of the physical activity guidelines for older adults were rarely reported (72/92, 78% and 80/92, 87%, respectively) or inaccurately reported (3/92, 3% and 3/92, 3%, respectively).ConclusionsInconsistent messages lead to mistrust of science and public health representatives. This work highlights the lack of evidence within existing open-access resources. Further efforts are needed to ensure evidence-based public health messages are in the sources and channels older adults are using to inform their knowledge and behaviors.

Microbial Ecology of Artisanal Feta and Kefalograviera Cheeses, Part I: Bacterial Community and Its Functional Characteristics with Focus on Lactic Acid Bacteria as Determined by Culture-Dependent Methods and Phenotype Microarrays.

Artisanal cheesemaking is still performed using practices and conditions derived from tradition. Feta and Kefalograviera cheeses are very popular in Greece and have met worldwide commercial success. However, there is a lack of knowledge regarding their lactic acid microecosystem composition and species dynamics during ripening. Thus, the aim of the present study was to assess the microecosystem as well as the autochthonous lactic acid microbiota during the ripening of artisanal Feta and Kefalograviera cheeses. For that purpose, raw sheep’s milk intended for cheesemaking, as well as Feta and Kefalograviera cheeses during early and late ripening were analyzed, and the lactic acid microbiota was identified using the classical phenotypic approach, clustering with PCR-RAPD and identification with sequencing of the 16S-rRNA gene, as well as with the Biolog GEN III microplates. In addition, the functional properties of the bacterial community were evaluated using the Biolog EcoPlates, which consists of 31 different carbon sources. In general, concordance between the techniques used was achieved. The most frequently isolated species from raw sheep’s milk were Enteroroccus faecium, Lactiplantibacillus plantarum and Pediococcus pentosaceus. The microecosystem of Feta cheese in the early ripening stage was dominated by Lp. plantarum and E. faecium, whereas, in late ripening, the microecosystem was dominated by Weissella paramesenteroides. The microecosystem of Kefalograviera cheese in the early ripening stage was dominated by Levilactobacillus brevis and E. faecium, and in late ripening by W. paramesenteroides and E. faecium. Finally, Carbohydrates was the main carbon source category that metabolized by all microbial communities, but the extent of their utilization was varied. Kefalograviera samples, especially at early ripening, demonstrated higher metabolic activity compared to Feta cheese. However, dominating species within microbial communities of the cheese samples were not significantly different.

Potential Risks of PM2.5-Bound Polycyclic Aromatic Hydrocarbons and Heavy Metals from Inland and Marine Directions for a Marine Background Site in North China.

Ambient PM2.5-bound ions, OC, EC, heavy metals (HMs), 18 polycyclic aromatic hydrocarbons (PAHs), 7 hopanes, and 29 n-alkanes were detected at Tuoji Island (TI), the only marine background atmospheric monitoring station in North China. The annual PM2.5 average concentration was 47 ± 31 μg m−3, and the average concentrations of the compositions in PM2.5 were higher in cold seasons than in warm seasons. The cancer and non-cancer risks of HMs and PAHs in cold seasons were also higher than in warm seasons. BaP, Ni, and As dominated the ∑HQ (hazard quotient) in cold seasons, while the non-carcinogenic risk in warm seasons was mainly dominated by Ni, Mn, and As. The ILCR (incremental lifetime cancer risk) values associated with Cr and As were higher in the cold season, while ILCR-Ni values were higher in the warm season. The backward trajectory was calculated to identify the potential directions of air mass at TI. Through the diagnostic ratios of organic and inorganic tracers, the sources of particulate matter in different directions were judged. It was found that ship emissions and sea salt were the main sources from marine directions, while coal combustion, vehicles emissions, industrial process, and secondary aerosols were the main source categories for inland directions. In addition, potential HM and PAH risks from inland and marine directions were explored. The non-cancerous effects of TI were mainly affected by inland transport, especially from the southeast, northwest, and west-northwest. The cancerous effects of TI were mainly simultaneously affected by the inland direction and marine direction of transport.

Ecological evaluation of heavy metal pollution in the soil of Pb-Zn mines.

Soil heavy metal pollution evaluations are a necessary measure for mine ecological control projects. In this study, the heavy metals Pb, Zn and Cd were studied in mining areas, tailings areas, sewage plant areas, residential areas, reclamation areas, and farmland areas. Soil pollution assessments of lead-zinc ore mine soils in the countryside of China are performed based on the index of geoaccumulation (Igeo) and the improved analytic hierarchy process (AHP). Finally, the pollution sources were analyzed by positive matrix factorization (PMF). The Igeo for the heavy metals Pb, Zn and Cd in the mining area reached 5.20, 3.34, and 5.66, respectively. In addition, 80 and 65% of the mining area and tailings area reached extremely strong pollution, respectively. The numerical simulation predicts that the pollution hazard in the southeast of the mine is high and that the pollution is concentrated. The severity of soil pollution in mines derived by the index of improved analytic hierarchy process (PAHP) was as follows: mining area (70.80) > sewage plant area (35.57) > tailings area (30.64) > farmland area (28.40) > residential area (21.11) > reclamation area (10.06). Among the three categories of pollution sources, one includes reclamation area, farmland area and tailings area; one includes sewage plant area and residential area; and one includes mining area. The source contribution of Pb by the phenomenon of indiscriminate discharge of wastewater after ore smelting was as high as 90.4%; The contribution of the blind mining and tailings piling phenomenon of mines to the source of heavy metals Zn and Cd was 81.4 and 90.2%, respectively. This study proposes a reliable scientific method and technical method for evaluating mine soil pollution and provides a guiding basis for mine development and protection.

Les débuts de la lexicographie multilingue roumaine: ressorts pragmatiques et influences culturelles

The Beginnings of Romanian Multilingual Lexicography: Pragmatic Sources and Cultural Influences. The beginnings of Romanian multilingual lexicography are deeply rooted in the first religious texts translated from Slavonic on the territory of the Romanian Principalities. The first dictionaries were aimed at fulfilling practical needs, being conceived as annexes to Slavonic or translated religious literature circulating at the time on the Romanian territory. This study provides an analysis of the first Romanian lexicographic projects, identifying their prototypes and describing the pragmatic background that these lexicographic initiatives were based on. Many of these works have sadly been lost, while others have been just partially preserved in private libraries. In these conditions, for the reconstruction of the Romanian lexicography belonging to that specific period, we resorted to two categories of sources: the notations and testimonies of the authors of the first lexicographic projects, and studies on the old Romanian lexicography. As they were not based on the rigorous scientific conception of a proper lexicographic school, the first Romanian dictionaries reflect the initiative of some scholars, revealing both their perspective on the role of such lexicographic tools and the stage of development of the Romanian language at the time.

La didáctica del paisaje en caso de discapacidad visual: algunas reflexiones para una deontología de la educación geográfica

This article presents some thoughts on landscape education in case of visual impairment. After four years of research spent on this matter, we would like to share with the scientific community an issue that is crucial for us, but substantially still ignored by literature. May the educator omit the visual meaning of the concept of landscape, or must they communicate it? What responsibilities, risks and benefits may emerge from one choice or the other? We believe that it is a delicate and significant problem, that cannot be bypassed simply resorting to non-visual forms of perception and meaning. Either way, we consider it an issue tackling the deontology of education, defining and therefore preceding any potential theoretical speculation or methodological solution. This is why we want to provide the reader with some conceptual tools useful to frame the issue and its possible implications from several points of view. In this case, the reflection on such implications will be conducted adopting and comparing three categories of sources: national and international normative sources; etymological and linguistic sources; sources from geographical theory. The result of these considerations suggests that, even in the context of visual impairment, the educator cannot avoid the duty to find the tools to communicate the visual value of landscape and, consequently, all the risks that this choice entails.

Proces o czary w Doruchowie w 1775 r. w świetle nowych źródeł

Many untrue hypotheses and information appeared around the “alleged” witchcraft trial in Doruchow in the second half of the 18th century, which resulted in the death of sever-al women. The text introduces a new category of sources: vital records registers and consistory records, which proved to be valuable material not only confirming the event itself, but also revealing the initiators of the trial, defendants, and witnesses.

Edycje akt sejmikowych ziem i województw prowincji małopolskiej

The sejmik (dietine) records of the Old Polish period are an invaluable source material concerning almost all aspects of the everyday life of that time. In the Małopolska (Little Poland) province, apart from the general sejmik sporadically held in Nowe Miasto Korczyn and occasional assemblies of the nobility from some lands and districts, there were 17 regular sejmiks. The paper first discusses all the editions of sejmik resolutions that have so far appeared in print. The study then presents the next volumes of this kind of source texts that are under preparation for publication. When describing the process of editing sejmik records, attention was drawn to the research centers that have made contributions to this research field, and to individual historians involved in such undertakings. The text also stresses the changes that took place in the first decades of the 20th century, when publishers took into account various categories of sources concerning the functioning of Old Polish sejmiks. A lot of room is devoted to the scope of library and archival research and to major stores of source materials that were and still are used by editors. The paper closes with a list of all existing and planned publications that are expected to appear in this field in the coming years.

Картографическое обеспечение идентификации природных и техногенных источников растворенного вещества в бассейне озера Байкал

A method of GIS mapping was developed to identify and assess the contributions of sources of matter to the composition of surface waters. The basis for the creation of the GIS database was the results of the study of the spatial diversity of the chemical composition of surface waters. Geoinformation analysis included the creation of a digital framework for mapping, vectorization of mapping sources and Earth remote sensing materials, creation of a single database combining cartographic, statistical information and field observation materials, morphometric relief analysis based on a digital relief model, creating a landscape basis for base maps, creating thematic maps, analyzing changes in the components of geosystems, creating electronic cartographic layers allowing to identify participation of solute sources in formation of water composition. The analysis of component changes was based on the results of different-time studies of the composition of water and bottom sediments. Based on the comparison of the chemical composition of the waters of the Baikal tributaries with the chemical and mineralogical composition of rocks, an approach was developed to identify sources of solute and assess their contributions to the formation of macro- and microelement compositions of surface waters. To solve the problems of the study, methods of statistical analysis of data, multicomponent mixing using systems of linear equations, field methods of data collection were used. Three main categories of solute sources (silicate, sulfide-containing silicate, carbonate rocks) were identified and their contributions to the chemical composition of water were calculated. On the basis of microelement tracers, the contributions of silicate rocks were divided into contributions of primary and secondary silicate rocks, ore-containing silicate rocks without sulfides were isolated. By comparing the ratios of concentrations of trace elements in the waters of uncontaminated territories and wastewater of enterprises, tracers were identified that made it possible to identify sources of surface water pollution. Maps of territories that determine a certain chemical composition of surface waters were compiled, which was first classified on the basis of the ratio of the contributions of drained rocks.

Photoluminescence characteristics of NaCl: Cu sintered dose tablets under X/γ irradiation

In this paper, NaCl: Cu circular dose tablets with a size of 5×1.8mm are prepared by sintering pure NaCl and CuCl powder as raw materials. They are placed in a four-element shell and sealed with plastic film to overcome the moisture absorption of the material. Their photoluminescence characteristics are studied by using an Inlight 200 automatic photoluminescence measurement system. The results show that the X-ray characteristic peaks of NaCl: Cu sintered at 650 ℃ and 400 ℃ appear at 27°, 32°, 45°, 56°, 66°, 75° and 84° respectively. Compared with the data given by XRD standard card of pure NaCl crystal (pdf-#88-2300), those peaks of the sample sintered at 650 ℃ are more consistent with the data given by the standard card. In the scanning electron microscope image, it can be seen that the grains are wholly welded and closely connected, and the characteristic grains in the sintering process have good welding effect. After Cu<sup>+</sup> ion doping, the lattice structure of NaCl is slightly deformed. After high-temperature sintering, the mass transfer of Cu<sup>+</sup> ions occurs at an atomic level in NaCl, and the particles are combined into a coherent solid structure. For X/γ-rays, the photoluminescence response of NaCl:Cu dose sheet to low-energy rays is higher than that of the same kind of rays with high energy. When using NaCl:Cu dose sheet to calculate the cumulative photoluminescence dose, it is necessary to consider the ray category and ray energy of the radiation source at the radiation site. The photoluminescence curve of NaCl:Cu dose sheet has typical exponential attenuation characteristics. The deflection angle of dose sheet has influence on the measured value: the greatest influence extent is 13.5%. With the increase of deflection angle of dose sheet, the area irradiated by γ-ray decreases, and the response of internal lattices to γ-ray decreases slightly. The uniformity of NaCl: Cu raw material particle sizes has a great influence on the distribution consistency of photoluminescence response of dose tablets. The decrease of sample particle size during tablet pressing can improve the contact surface area between NaCl and CuCl. The increase of contact surface area can improve the diffusion and transfer efficiency of Cu<sup>+</sup> ions, increase the number of dose traps in the crystal, and make the overall count higher. When the particle sizes are more uniform, the Cu<sup>+</sup> ion transferefficiencies and quantities of different dose tablets are close, the difference in the number of dose traps is reduced, and the photoluminescence sensitivities are closer. The coefficient of variation of the repeatability test experiment is 2.28%. The consistency of the repeated measurement data is good. The lattice structure and lattice defects of the material are not changed in the process of photoluminescence measurement and photoannealing. In a dose range of 1-1000mgy, with the increase of irradiation dose, the photoluminescence response of NaCl: Cu and NaCl dose tablets gradually increase and show a good linear relationship. The photoluminescence response of NaCl: Cu is 2-to-4 times higher than that of NaCl dose tablets. The NaCl: Cu dose tablets prepared by the sintering method can be used as dosimeters for monitoring personal or environmental dose.

Developing a Pilot Biogas-Solar PV System for Farming Communities in Botswana: Case of Palapye

Palapye is one of the fastest growing urban centers in Botswana. The projection of this urbanization shows a subsequent high rate of waste generation in the future with a composition of over 50 % of organic compounds from discarded foods. Several studies show that there is currently no effective waste management system in this town. For this reason, this paper sought to succinctly propose the design of a pilot 9 kW Biogas-Solar Photovoltaic (PV) Hybrid Mini-grid (BSPVHM) as a tool for an effective waste management plan and an alternative energy and agricultural solution for local farming communities. The designed pilot BSPVHM is composed of four sections which are the power generation section (with a 5-kW biogas and a 4 kWp solar PV power units), the power back-up section (with a 5 kVA diesel genset and a 6-kWh lithium-ion battery), the energy management system (EMS) section (with a 4.6 kW inverter and remote and on-site monitoring instruments) and the power supply section (with a low voltage cable). The town of Palapye was selected as the site of the pilot project because of its high waste generation capacity estimated at an average of 0.20 kg/capita/day from various categories of domestic sources. Additionally, the noticeable presence of farming communities and the yearly solar photovoltaic power potential ranging between 1753 - 1899 kWh were other reasons for this selection. Based on these available ressources, it was assumed that BSPVHM will supply at domestic scale, solar power from panels for 12 hours from 6 AM to 6 PM, power from the biogas generator for 6 hours from 6 PM to 12 AM and power from the back up section from 12 AM to 6 AM. The supply of electricity will be done autonomously by the BSPVHM system under a limited physical monitoring.