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Studying the changes in organic matter and characteristic pollutants during the treatment of penicillin-containing pharmaceutical wastewater, which can be reflected by changes in dissolved organic matter (DOM), is crucial for improving the effectiveness of wastewater treatment units and systems. Herein, water quality indicators, spectroscopic methods, and Fourier-transform ion cyclotron resonance mass spectrometry were utilized to characterize the general molecular compositions and specific molecular changes in DOM during the treatment of typical penicillin-containing pharmaceutical wastewater, including in each of the influent, physicochemical treatment, biological treatment, oxidation treatment, and effluent stages. The influent exhibited a high organic matter content (concentration of dissolved organic carbon >10,000 mg·L−1), its DOM mainly contained protein- and lignin-like substances composed of CHON and CHONS molecules, and the relative intensity (RI) of penicillin was extremely high (RI = 0.220). Compared with the influent, the abundance of CHON and CHONS molecules detected after physicochemical treatment decreased by 70.3 % and 62.5 %, respectively, and the RI of penicillin decreased by 85.5 %. Biological treatment caused substantial changes in DOM components through oxidation, dealkylation, and denitrification reactions, accounting for 36.8 %, 28.9 %, and 14.8 % of the total identified reactions, respectively. Additionally, lignin-like substances were generated in large quantities, the overall humification level significantly increased, and the RI value increased for the penicillin intermediate, 6-aminopenicillanic acid (6-APA). Oxidation treatment effectively removed phosphorus-containing substances and some lignin-like substances produced by biological treatment; however, it was not effective in removing characteristic pollutants such as 6-APA. Such characteristic substances continued to be present in the effluent, and the DOM mainly contained protein- and humus-like substances, accounting for 30.8 % and 47.3 %, respectively. The study findings reveal the changes in organic matter and characteristic pollutants during the treatment of penicillin-containing wastewater from the perspective of the general molecular composition and specific molecular changes in DOM, providing support for further exploration of wastewater treatment mechanisms and improvements in treatment unit efficiency. [Display omitted] • Spectroscopic methods and FT-ICR MS analyzed DOM characteristic changes during wastewater treatment process. • DOM in the influent was mainly composed of protein- and lignin-like substances. • Lignin-like substances and CHONS molecules were produced after biological treatment. • Biological treatment and advanced oxidation treatment were difficult to remove sulfur-containing DOM molecules. [ABSTRACT FROM AUTHOR]

Sufficient levels of thermal, electrical, mechanical, or electrochemical abuse can cause thermal runaway in lithium-ion batteries, leading to the release of electrolyte vapor, combustible gas mixtures, and high-temperature particles. Particle emissions due to thermal failure of batteries may cause serious pollution of the atmosphere, water sources, and soil as well as enter the human biological chain through crops, posing a potential threat to human health. Furthermore, high-temperature particle emissions may ignite the flammable gas mixtures produced during the thermal runaway process, resulting in combustion and explosions. This research focused on determining the particle size distribution, elemental composition, morphology, and crystal structure of particles released from different cathode batteries after thermal runaway. Accelerated adiabatic calorimetry tests were performed on a fully charged Li(Ni 0.3 Co 0.3 Mn 0.3)O 2 battery (NCM111), Li(Ni 0.5 Co 0.2 Mn 0.3)O 2 battery (NCM523), and Li(Ni 0.6 Co 0.2 Mn 0.2)O 2 battery (NCM622). Results of all three batteries indicate that particles with a diameter less than or equal to 0.85 mm exhibit an increase in volume distribution followed by a decrease in volume distribution as the diameter increases. F, S, P, Cr, Ge, and Ge were detected in particle emissions with mass percentages ranging from 6.5% to 43.3%, 0.76–1.20%, 2.41–4.83%,1.8–3.7%, and 0–0.14%, respectively. When present in high concentrations, these may have negative impacts on human health and the environment. In addition, the diffraction patterns of the particle emissions were approximately the same for NC111, NCM523, and NCM622, with emissions primarily composed of Ni/Co elemental, graphite, Li 2 CO 3 , NiO, LiF, MnO, and LiNiO 2. This study can provide important insights into the potential environmental and health risks associated with particle emissions from thermal runaway in lithium-ion batteries [Display omitted] • Particle emissions from different cathode batteries were analyzed physically and chemically. • 88–90% of the total particle emissions were less than or equal to 0.85 mm. • The volume of small particle emissions increases first and then decreases. • Particle emissions contain elements that are harmful to human health. • Diffraction patterns for particle emissions from Li(Ni x Co y Mn z)O 2 cathodes are basically the same. [ABSTRACT FROM AUTHOR]

Morphology and elemental composition of individual fine ambient particles varied among types of PM events and between two different urban environments having different major transportation systems (gasoline/diesel vehicles versus motorcycles). Carbonaceous particles were the most dominant in PM events, whereas S-rich particles were the highest in non-events at urban Gwangju in Korea. The aged soot, semi-volatile organic (SVO), and non-volatile organic (NVO) particles were more abundant in the polluted-long range transport (LTP) event than those in the dust-LTP event and non-event. In the dust-LTP event, the aged mineral dust particles outnumbered the fresh ones, suggesting the mineral dust particles were aged during their long-range transport. At HoChiMinh (HCM) in Vietnam, the fraction of carbonaceous particles was much higher than Gwangju (66% versus 30%) possibly due to more abundant two-stroke motor vehicles at HCM. Of the carbonaceous particles, combustion soot (19%) was the highest, followed by NVO (18%), SVO (17%), and biological particles (11%) at HCM, whereas SVO (11%) and NVO (10%) particles were the highest, followed by combustion soot particles (8%) at Gwangju. The higher fraction of mineral dust particles was also observed at HCM, indicating the sampling site was influenced by dust from unpaved roads and construction sites. [ABSTRACT FROM AUTHOR]

Thirty-three samples of construction and demolition waste collected at 11 recycling facilities in Denmark were characterised in terms of total content and leaching of inorganic elements and presence of the persistent organic pollutants PCBs and PAHs. Samples included (i) "clean" (i.e. unmixed) concrete waste, (ii) mixed masonry and concrete, (iii) asphalt and (iv) freshly cast concrete cores; both old and newly generated construction and demolition waste was included. PCBs and PAHs were detected in all samples, generally in non-critical concentrations. Overall, PAHs were comparable to background levels in urban environments. "Old" and "new" concrete samples indicated different PCB congener profiles and the presence of PCB even in new concrete suggested that background levels in raw materials may be an issue. Significant variability in total content of trace elements, even more pronounced for leaching, was observed indicating that the number of analysed samples may be critical in relation to decisions regarding management and utilisation of the materials. Higher leaching of chromium, sulphate and chloride were observed for masonry-containing and partly carbonated samples, indicating that source segregation and management practices may be important. Generally, leaching was in compliance with available leaching limits, except for selenium, and in some cases chromium, sulphate and antimony. [ABSTRACT FROM AUTHOR]

A new pathway has been introduced to predict detonation pressure of CHNO and CHNOAl explosives. Although aluminized explosives can have Chapman-Jouguet detonation performance significantly different from those expected from existing thermodynamic computer codes for equilibrium and steady state calculations, new correlation can also be used here. Molecular structures of CHNO and CHNOAl explosives are the only necessary parameters that would be needed in this new scheme. There is no need to use heat of formation or any experimental data. Besides, elemental compositions of CHNO and CHNOAl explosives rather than assumed detonation products are essential input parameters. Predicted detonation pressures for CHNO explosives are compared with experimental data as well as computed results gained by complicated computer code using BKWR and BKWS equations of state so the new method shows the best results. Also, the calculated results for CHNOAl explosives indicate good agreement with the measured data as compared to estimated results of BKWS-EOS using full and partial equilibrium. [Copyright &y& Elsevier]

This paper describes a simple method for prediction of detonation velocity of ideal and non-ideal explosives. A non-ideal aluminized and nitrated explosive can have Chapman¿Jouguet detonation velocity significantly different from that expected from existing thermodynamic computer codes for equilibrium and steady-state calculations. Detonation velocity of explosives with general formula C a H b N c O d Al e can be predicted only from values of a, b, c, d, e and a specific structural parameter without using any assumed detonation products, heat of formation and experimental data. Predicted detonation velocities by this procedure for ideal and non-ideal explosives show good agreement with respect to experimental values as compared to computed results of BKWR and BKWS equations of state. [Copyright &y& Elsevier]

Welding fumes (WFs) can cause occupational pneumonoconiosis and other diseases in workers. WFs have complex chemical composition and morphology depending on the welding conditions. The WF surface is a key factor affecting those diseases. The objective of this study was to establish an analytical method focused on characterizing individual WFs and welding slags (WSs) formed during CO 2 arc welding processes for knowledge acquisition of risk assessment. Especially, the characterization was focused on the elemental distributions near the surfaces obtained using fluxing agents and size of the WFs. WFs were collected using personal samplers. After welding, WS was also collected. The fluxing elemental distribution (e.g., Bi) near the surfaces WS and WFs were analyzed through scanning electron microscopy and energy-dispersive X-ray spectroscopy. As a result, some of the micron-sized spherical particles (SPs) grew by incorporating nanosized primary particles composed of other metal species. The fluxing agents formed elemental distribution patterns on the SP surface. Bi were dotted in an agglomerate. Mn amount in WS depends on Mn amount in the WFs. These results obtained through the analysis of both the WS and WF surface as well as the particle sizes will facilitate the establishment of exposure assessment models. [Display omitted] • An analytical method for WF and WS was proposed using SEM-EDX elemental mapping. • Some WFs grew by incorporating other metal primary particles. • Each Cr and Fe was distributed on divided surfaces of some micron sized WF spherical particles. • Fluxing agents contributed to formation of surface patterns on micron sized WF spherical particles. • Bismuth was dotted in the agglomerates of nano-sized WF particles. [ABSTRACT FROM AUTHOR]

Abstract: PM2.5 samples were collected in Shanghai at four sites with different typical land-uses. The sampling was done concurrently once per month from April 2004 to April 2005, and the ambient mass concentration, the elemental composition and the stable lead isotope ratios in these PM2.5 samples were determined. The annual average concentrations of PM2.5 samples at each site were 84±30, 65±20, 55±18, and 41±10μgm−3, respectively, indicating there were severe air pollution levels in Shanghai. The enrichment factor was calculated for each element and the comparison and discussion of elements with significant anthropogenic contributions between Shanghai and Tokyo suggested that the major source of PM2.5 in Shanghai was not traffic-derived emissions, but the stationary industrial contribution emitted from coal use. Moreover, the analysis of stable lead isotope ratios revealed only a slight difference within the samples at the four sites which fell well within the scope of coal composition difference, further confirming that the contribution from stationary industrial emissions to atmospheric lead pollution of PM2.5 was very substantial in Shanghai. [Copyright &y& Elsevier]

A new model has been introduced for simple calculation of crystal density of an important class of organic explosives, namely nitroaromatic energetic compounds. This model is based on the fundamental correlation. The introduced procedure has been applied to 60 well-known and new synthesized organic nitroaromatic explosives. The results show that the present method gives comparable prediction respect to well-developed group additivity method for estimation of crystal density of organic explosives. The introduced simple method can be applied to any complex nitroaromatic explosive that contains the elements of carbon, hydrogen, nitrogen and oxygen with no difficulties. [Copyright &y& Elsevier]

A novel approach to density prediction by elemental composition is developed for various important classes of explosives. Some correlations based on two different models are introduced for 82 different energetic compounds whose molecules contain functional groups common to C a H b N c O d explosives. These include acyclic and cyclic nitramines, nitrate esters and nitroaliphatic compounds. Of the 69 well-known and recently new synthesized organic explosives for which direct comparison could be made with Tarver group additivity method, root mean square (rms) of deviation for 19 acyclic and cyclic nitramines is 2.839 and 3.412 while for 50 nitrate esters and nitroaliphatic explosives is 1.936 and 1.752 for new and Tarver's method, respectively. This method is the simplest procedure for calculating density of energetic compounds which gives good results as compared to well-developed group additivity method for estimation density of organic explosives. [Copyright &y& Elsevier]

Abstract: The simplest method is introduced for reliable estimating the detonation velocity of large class of CHNO explosives based elemental composition and specific structural groups. There is no need to use heat of formation and the other experimental data for calculation of detonation velocity in the new procedure. Only elemental composition and the number of special structural groups without using heat of formation of explosive is sufficient for reliable desk calculation of detonation velocity. The results show good agreement with experimental values with respect to computed results obtained by complex computer code using BKWS and BKWR equations of state. Predicted velocities of detonation have root-mean-square (rms) percent deviation of 2.2, 5.9 and 5.3 from experimental data for new method, BKWS and BKWR equations of state, respectively. [Copyright &y& Elsevier]

Abstract: A new scheme is introduced for calculating detonation temperature of different classes of high explosives. The ratio of oxygen to carbon and hydrogen to oxygen as well as specific structural parameters are the fundamental factors in the new method. An empirical new correlation is used to calculate detonation temperature of energetic compounds without considering heat contents of explosives and detonation products. Calculated detonation temperatures for both pure and explosive formulations show good agreement with respect to measured detonation temperatures and complicated computer code using BKWR and BKWS equations of state. Predicted detonation temperatures have root-mean-square (rms) percent deviation of 4.6, 14.2 and 4.6 from measured values for new method, BKWR and BKWS equations of state, respectively. [Copyright &y& Elsevier]

Abstract: Non-ideal explosives can have Chapman–Jouguet (C–J) detonation pressure significantly different from those expected from existing thermodynamic computer codes, which usually allows finding the parameters of ideal detonation of individual high explosives with good accuracy. A simple method is introduced by which detonation pressure of non-ideal aluminized explosives with general formula C a H b N c O d Al e can be predicted only from a, b, c, d and e at any loading density without using any assumed detonation products and experimental data. Calculated detonation pressures show good agreement with experimental values with respect to computed results obtained by complicated computer code. It is shown here how loading density and atomic composition can be integrated into an empirical formula for predicting detonation pressure of proposed aluminized explosives. [Copyright &y& Elsevier]

Microplastics (MPs) can be easily taken up by a wide range of aquatic animals and cause blockage of the digestive tract leading to starvation. Meanwhile, aquatic organisms are facing threats posed by food restriction in both wild and cultured environment. Little knowledge, however, exists on how MPs interact with food conditions to affect aquatic animals. Here, koi carp were exposed to polystyrene MPs (0, 100 or 1000 μg/L) under controlled feeding (satiated or starved) for 30 or 60 days. MPs reduced and interacted synergistically with food conditions on growth after 30 days but antagonistically after 60 days. MPs reduced crude lipid and carbohydrate but increased and antagonistically interacted with feeding conditions on crude protein. Food conditions interacted with MPs on C, N and P but stoichiometric responses were decoupled with macromolecules changes. Food conditions antagonistically interacted with MPs on δ13C after 60 days. Linear discriminant analysis revealed that C:P and N:P were the two most important measured parameters accounting for the response of koi towards MPs and food restriction, presenting an antagonistic interaction of MPs and food status with the prolonged exposure duration. ga1 • MPs reduced growth and interacted synergistically with food condition after 30 days but antagonistically after 60 days. • Food restriction antagonistically interacted with MPs on crude protein after both 30 and 60 days. • Food condition antagonistically interacted with MPs on δ13C after 60 days. • C:P and N:P might account for the response of koi towards MPs and food restriction. [ABSTRACT FROM AUTHOR]

• A new method is proposed to characterize chemical features of biomass and waste. • The method is based on infrared spectroscopy and machine learning models. • The method is fast and the optimal accuracy could reach as high as 95.54%. • The robustness of this method is validated, and its properties are discussed. • The method can enhance sorting of biomass and waste for downstream utilization. Heterogeneity is a most serious obstacle for treatment and utilization of biomass and waste (BW). This paper proposed a fast characterization method based on infrared spectroscopy and machine learning models, thus to roughly predict the elemental composition and heating value of BW. The fast characterization results could be used to sort different BW components by their suitable downstream utilization techniques. The infrared spectra based hybrid model contained a feature compression section to extract core information from raw infrared spectra, a classification section to distinguish inorganic dilution, and a regression section to generate the elemental composition and heating value results. By parameters optimization, the accuracy of this hybrid model reached 95.54%, 85.53%, 92.40%, and 92.49% for C content, H content, O content, and low heating value prediction, respectively. The robustness analysis was conducted by completely rearranging the training and test sets, and it further validated the hypothesis that the infrared spectra contains enough qualifying and quantifying information to characterize these properties of BW. Compared with previous literature, the C–H, C–O, and O–H correlations in BW were also well kept in the predicted results. This work is hoped to enhance upstream sorting system design for treatment and utilization of BW. [ABSTRACT FROM AUTHOR]