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Plastics possess diverse functional properties that have made them extremely desirable. However, due to poor waste management practices, large quantities eventually end up in the oceans where their degradation begins. Hence, it is imperative to understand and further investigate the dynamics of this process. Currently, most relevant studies have been carried out under benign and/or controlled weather conditions. This study investigates the natural degradation of polypropylene (PP) and polyethylene terephthalate (PET) in more extreme environments. Simulated and real marine conditions, both in the laboratory (indoors) and outdoors were applied for a duration of 140 days and results were assessed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) with energy dispersive X-ray analysis. SEM micrographs revealed variations in the morphologies of both plastic types. Degradation signs were shown in both plastic types, under all conditions. Findings indicated that microplastics (MPs) degraded faster than macroplastics, with PP MPs having higher weight loss (49%) than PET MPs (1%) when exposed to outdoor marine conditions. Additionally, the degradation rates of MPs-PP were higher than MPs-PET for outdoor and indoor treatments, with 1.07 ×10-6g/d and 4.41 ×10-7g/d, respectively. FTIR combined with PCA was efficient in determining the most degraded plastic types. This paper was supported by Qatar University Internal Grant (No. QUCG-CAS-21/22-3). The findings achieved herein are solely the responsibility of the authors. The SEM-EDX, DSC, and FTIR analyses were accomplished in the Central Laboratories unit, Qatar University.

Lithium-sulfur (Li–S) batteries are among the most promising next-generation energy storage technologies due to their ability to provide up to three times greater energy density than conventional lithium-ion batteries. The implementation of Li–S battery is still facing a series of major challenges including (i) low electronic conductivity of both reactants (sulfur) and products (polysulfides) that limits the rate capability of the battery; (ii) high solubility of the polysulfide products into the electrolyte that affects the cycle life; and (iii) the reactivity of the lithium metal anode that induces serious safety hazards. Replacing hazardous organic electrolytes with solid-state electrolytes (SSEs) can prevent lithium polysulfides crossover and Li dendrite growth. SSEs with high ionic conductivity and good electrochemical stability can boost Li–S technology by improving electrochemical performance and cycling stability. All-solid lithium-sulfur batteries (SLSBs), comprising of sulfur cathode, solid electrolyte, and Li metal anode, are much safer than liquid-based electrochemical batteries such as conventional lithium batteries. They possess longer cycle life and require less effort in terms of packaging and monitoring circuits. SLSBs have the powerful ability to transfer the converted stored chemical energy into electrical energy with high efficiency and without the release of harmful gasses. This review focuses on the types of SSEs, their advantages and drawbacks in conjunction with Li–S batteries, and the challenges that hinder the practical application of SLSBs.

Titan yellow (TY), a triazene azo dye, was removed from contaminated wastewater samples using a green adsorbent recycled from Aloe vera leaves (AV) waste. Two adsorbents were developed&mdash, air-dried Aloe vera (ADAV) and thermally treated Aloe vera (TTAV). Adsorption efficacy of both adsorbents was assessed in terms of percent removal (%R) of TY and adsorption capacity (qe). ADAV had a better performance compared to TTAV. Plackett&ndash, Burman design (PBD) was exploited to establish the experimental pattern of the study. Four variables were studied: pH, adsorbent dose (AD), dye concentration (DC), and stirring time (ST). Analysis of variance (ANOVA) at 95.0 confidence interval (CI), control, and quality charts helped establish regression model(s). Characterization of both adsorbents was performed using FT-IR/Raman spectroscopy together with TGA/dTGA and SEM/energy dispersive X-ray spectroscopy (EDX) analyses. Textural properties were determined using nitrogen adsorption isotherms at 77 K. Results showed that the surface areas of ADAV and TTAV300 were 3.940 and 7.076 m2/g, respectively. Raman analysis showed that the TTAV had clear D- and G-bands. Equilibrium studies revealed that data were well fitted to Freundlich isotherm with a maximum adsorption capacity of 55.25 mg/g using Langmuir equation, and the adsorption was physisorption. Adsorption followed a pseudo-second order that occurred in two steps&mdash, diffusion and then adsorption.

Background Monitoring seasonal influenza epidemics is the corner stone to epidemiological surveillance of acute respiratory virus infections worldwide. This work aims to compare two sentinel surveillance systems within the Daily Acute Respiratory Infection Information System of Catalonia (PIDIRAC), the primary care ILI and Influenza confirmed samples from primary care (PIDIRAC-ILI and PIDIRAC-FLU) and the severe hospitalized laboratory confirmed influenza system (SHLCI), in regard to how they behave in the forecasting of epidemic onset and severity allowing for healthcare preparedness. Methods Epidemiological study carried out during seven influenza seasons (2010-2017) in Catalonia, with data from influenza sentinel surveillance of primary care physicians reporting ILI along with laboratory confirmation of influenza from systematic sampling of ILI cases and 12 hospitals that provided data on severe hospitalized cases with laboratory-confirmed influenza (SHLCI-FLU). Epidemic thresholds for ILI and SHLCI-FLU (overall) as well as influenza A (SHLCI-FLUA) and influenza B (SHLCI-FLUB) incidence rates were assessed by the Moving Epidemics Method. Results Epidemic thresholds for primary care sentinel surveillance influenza-like illness (PIDIRAC-ILI) incidence rates ranged from 83.65 to 503.92 per 100.000 h. Paired incidence rate curves for SHLCI -FLU / PIDIRAC-ILI and SHLCI-FLUA/ PIDIRAC-FLUA showed best correlation index' (0.805 and 0.724 respectively). Assessing delay in reaching epidemic level, PIDIRAC-ILI source forecasts an average of 1.6 weeks before the rest of sources paired. Differences are higher when SHLCI cases are paired to PIDIRAC-ILI and PIDIRAC-FLUB although statistical significance was observed only for SHLCI-FLU/PIDIRAC-ILI (p-value Wilcoxon test = 0.039). Conclusions The combined ILI and confirmed influenza from primary care along with the severe hospitalized laboratory confirmed influenza data from PIDIRAC sentinel surveillance system provides timely and accurate syndromic and virological surveillance of influenza from the community level to hospitalization of severe cases.

Mannitol is a polymorphic excipient which is usually used in pharmaceutical products as the beta form, although other polymorphs (alpha and delta) are common contaminants. Binary mixtures containing beta and delta mannitol were prepared to quantify the concentration of the beta form using FT-Raman spectroscopy. Spectral regions characteristic of each form were selected and peak intensity ratios of beta peaks to delta peaks were calculated. Using these ratios, a correlation curve was established which was then validated by analysing further samples of known composition. The results indicate that levels down to 2% beta could be quantified using this novel, non-destructive approach. Potential errors associated with quantitative studies using FT-Raman spectroscopy were also researched. The principal source of variability arose from inhomogeneities on mixing of the samples; a significant reduction of these errors was observed by reducing and controlling the particle size range. The results show that FT-Raman spectroscopy can be used to rapidly and accurately quantitate polymorphic mixtures.

Mannitol is a polymorphic parmaceutical excipient, which commonly exists in three forms: alpha, beta and delta. Each polymorph has a needle-like morphology, which can give preferred orientation effects when analysed by X-ray powder diffractometry (XRPD) thus providing difficulties for quantitative XRPD assessments. The occurrence of preferred orientation may be demonstrated by sample rotation and the consequent effects on X-ray data can be minimised by reducing the particle size. Using two particle size ranges (