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Radiative cooling without energy consumption and environmental pollution holds great promise as the next-generation cooling technology. To date, daytime radiative cooling performance is still slightly low, especially in humid areas. In this work, we demonstrated that nanoporous polyethylene (Nano PE) film can improve solar reflectivity from 96% to 99%, thus boosting radiative cooling performance. Moreover, the experimental results in humid areas indicate that Nano PE films can improve radiative cooling performance by ∼76% in a clear day and 120% in a day with few clouds. Additionally, compared with ordinary PE films, thin Nano PE films have significantly higher weather fastness and mechanical strength. More importantly, nano PE films can scatter part of visible light, thus suppressing the generation of light pollution in practical applications. Lastly, the modeling results reveal that with Nano PE films, more than 95% of China's areas can achieve daytime cooling performance. Our work can boost the development of radiative cooling technology with a very low cost.

In a circular economy perspective, solid plastic wastes (SPW) can become a valuable source of chemicals, energy vectors and fuels through pyrolysis, gasification, and partial oxidation technologies, but their modelling requires first the definition of suitable condensed phase pyrolysis mechanisms for each constituent. This work proposes a semi-detailed kinetic model for polyethylene (PE) and polypropylene (PP) pyrolysis based on the functional group approach implemented for polyvinylchloride (PVC) and biomass pyrolysis to consistently address mixture modelling. This approach distinguishes polymeric chains in High Molecular Weight species, represented through their chemical functionalities, and Low Molecular Weight species, described with accuracy comparable to literature detailed models, employing the reaction classes proposed in the scientific literature. Several validated lumping techniques are introduced to reduce the model computational cost, and the resulting liquid-phase model accounts for 74 species for PE and 126 species for PP. Model validation is carried out by an extensive comparison with experimental data proving the soundness of the approach and the model capability of predicting mass-loss and product distribution profiles with similar accuracy to more expensive detailed models from the literature. The proposed condensed phase approach can be extended to other polymers and coupled with other existing subsets in the CRECK kinetic framework (e.g., biomass, PVC) paving the way for unravelling mixture interactions and secondary cracking and/or gasification reactions. The model here proposed is a powerful tool to support design and optimization of SPW thermochemical recycling technologies.

Composting poultry carcasses and the infected litter is considered feasible during mass depopulation events in response to disease outbreaks. We demonstrate the effect of temperature (40, 50, 60 °C) and aerobic/anaerobic conditions on the degradation of broiler carcasses and broiler litter (BL) and the elimination of pre-inoculated Avian flu and Newcastle viruses and SalmonellaInfantis (3.3 × 10

This research explores a segment of the mechanical, thermal & physical characteristics of a polymer polypropylene (PP) mixture including low density polyethylene (LDPE). There were mixing syntheses (pure PP, 25 LDPE/75PP, 50LDPE/50PP, 75LDPE/25LDPE, pure PP) that were examined. As outcome, the expansion of LDPE to PP has decreased, with improved thickness, elasticity, bending efficiency, versatile modulus and hardness. In a (25LDPE/75PP) arrangement the prevailing elasticity was achieved while the (50LDPE/50PP) synthesis was attributed to ideal bent efficiency. High density polyethylene (HDPE) blowing in different proportions PP/polyethylene (PEs) can remove sorting course employed during even recycling course. PP has interesting features like outstanding process ability &tolerance to chemicals. Inadequate versatility, however, limits its usage in specific applications. Mixing PP with relative PEs may enhance its versatility. Universal kinetics of PP crystallization have been affected greatly by the existence of PEs of various structures of the ramifications. Existence of LDPE reduced overall summation ratio while HDPE increased the process of crystallization. No negative effect was observed in the studied parameter range on mechanical performance and the related crystallinity.

Co-pyrolysis of lignin and waste plastics, for example polyethylene (PE), has been studied, but related reports are basically on condition optimizations. This study revealed a new perspective on PE-promoted lignin pyrolysis to phenolic monomers with mass transfer and radical explanation. Lignin and PE were first pyrolyzed individually to identify pyrolysis characteristics, pyrolytic products, as well as the suitable co-pyrolysis temperature. Then, co-pyrolysis of blended lignin/PE with various ratios was investigated. Yields of lignin products reached the maximum under lignin/PE ratio of 1:1, but blended approach always inhibited the production of lignin phenols. This resulted from the poor mass transfer and interactions between lignin and PE, in which PE pyrolysates could easily escape from the particle gaps. While in layered approach, PE pyrolysates had to pass through the lignin layer which contributed to the good interactions with lignin pyrolysis intermediates, thus the yields of lignin-derived products were significantly improved. Interactions between lignin and PE (or their pyrolysates) were mainly radical quenching reactions, and X-ray photoelectron spectrum (XPS) and electron paramagnetic resonance (EPR) of pyrolytic chars were conducted to verify these interactions controlled by mass transfer. The percentage of C C (sp2) and concentration of organic stable radicals in layered lignin/PE char were both the lowest compared with those in blended lignin/PE and lignin char, indicating the stabilization of lignin-derived radicals by PE pyrolysates. Moreover, the spin concentration of radicals in the char from layered char/PE was lower than that in lignin char, which further affirmed the quenching of radicals by PE in the layered co-pyrolysis mode.

The primary purpose of this study was to compare 2-year anatomic total shoulder arthroplasty (TSA) functional and radiographic outcomes between Walch type A and B glenoids treated with an all-polyethylene glenoid designed for hybrid fixation with peripheral cement and central osseous integration. The secondary purpose was to evaluate outcomes based on central peg technique. The hypotheses were that there would be no difference in short-term radiographic or functional outcome scores based on preoperative glenoid morphology or central peg technique.We performed a multicenter retrospective review of patients who underwent TSA with the same hybrid all-polyethylene glenoid and had minimum 2-year follow-up. Patient-reported outcomes and radiographic outcomes were analyzed based on preoperative Walch morphology and central peg technique. Radiographic analysis included preoperative glenoid morphology; preoperative and postoperative glenoid version, glenoid inclination, and posterior humeral head subluxation; and postoperative glenoid radiolucencies according to the Wirth and Lazarus classifications.A total of 266 patients with a mean age of 64.9 ± 8.2 years were evaluated at a mean of 28 months postoperatively. Postoperatively, there were significant improvements in all functional outcome measures (P .001), range-of-motion measures (forward elevation, external rotation at 0°, external rotation at 90°, internal rotation by spinal level, and internal rotation at 90°; P .001), and strength measures (Constant, external rotation, and modified belly press; P .001). There were no clinically meaningful differences in functional outcomes or statistically significant differences in radiographic appearance between Walch type A and B glenoids. Subgroup analysis revealed that glenoids with a cemented central peg had the worst radiographic outcomes based on Lazarus scoring.Patients undergoing TSA with a hybrid in-line pegged glenoid have excellent clinical outcomes at short-term follow-up regardless of preoperative glenoid morphology. Different central peg techniques do not appear to play a significant role in the risk of glenoid component lucencies at 2 years postoperatively.

Skin grafting continues to be a fundamental component of burn treatment and inherently, a donor site must be created and treated. Burn surgeons agree that specific dressings may have a significant affect on donor site healing, but we have no consensus as to which dressing provides maximum benefit.Retrospective analysis of prospectively collected data from an observational, within-patient controlled assessment of a practice pattern intervention. The project compared donor sites treated with high-density polyethylene plus an overlying layer of bismuth/petroleum gauze to donor sites treated with bismuth/petroleum gauze alone. The primary endpoint was patient reported pain using a standard visual analog scale from 0 (no pain) to 10 (worst possible pain). A 2-point reduction in pain was considered clinically significant. Healing was defined as complete detachment of the dressings and 95% wound re-epitheliazation.A total of 30 patients were observed and analyzed. Both dressings were associated with a mean pain rating of 6 out of 10 (STD= ± 2) and a median pain rating of 6 out of 10 (range = 0-10). Additionally, both dressings were associated with a mean healing time of 20 days (SEM=1.1). The subjective dressing preference showed that a majority of patients had no preference between the two modalities (n = 20). However, when an actual preference was stated (n = 10), bismuth/petroleum gauze alone was preferred by 9 out of 10 patients.Clinically and subjectively, we found no discernible differences between the 2 dressing regimens. Thus, bismuth/petroleum gauze alone is the more cost effective dressing choice. Our burn center continues to use bismuth/petroleum gauze alone as its standard of care for donor site dressings and will continue to try to define the optimal donor site dressing.

Revision total hip arthroplasty (THA) for adverse local tissue reactions (ALTRs) secondary to head-neck taper corrosion is associated with a high complication rate. Diagnosis of ALTR is based on risk stratification using the patient's history and examination, implant risk, serum metal ion levels, and imaging. The purpose of this study was to determine if stratification using similar risk factors is predictive of outcomes following revision THA for metal-on-polyethylene (MoP) ALTR.We performed a retrospective review on 141 patients revised for ALTR due to head-neck taper corrosion. Pain outcomes following surgery were analyzed using a generalized linear mixed model. Complications were defined as instability/dislocation, infection, fracture, nerve palsy, leg-length discrepancy, or reoperation.The overall complication rate was 17.7%. The odds of having pain decreased by 44% after revision surgery (Odds Ratio = 0.56, 95% Confidence Interval: 0.324 to 0.952). There was no significant difference in instability/dislocation based on either increased or decreased head-neck offset (P = .67) or magnetic resonance imaging findings of abductor loss, effusion size, and degree of ALTR (P = .73). Increased serum cobalt (P = .31) and chromium (P = .08) levels did not predict complications; however, a decreased cobalt-chromium ratio was associated with postoperative complications (2.8 versus 3.5; P = .002).These findings are the first to suggest that patients who have ALTR after MoP THA undergoing revision surgery demonstrated major pain relief. Increasing femoral head offset did not change rates of instability/dislocation. In clinical scenarios where preoperative cobalt-chromium femoral head offsets were greater than available ceramic head offsets, a mandatory decrease in femoral head offset did not increase rates of instability/dislocation.

Canola meal is a low-value agricultural residue obtained after oil extraction from canola, the utilization of which requires further attention. On the other hand, plastic waste disposal is also another leading issue that creates severe environmental challenges. Supercritical water gasification is considered an environmentally friendly technology to produce hydrogen from plastic residues and organic wastes. This study deals with hydrothermal co-gasification of canola meal and plastic wastes (i.e., low-density polyethylene) while exploring the influence of temperature (375–525°C), residence time (15–60 min) and plastic-to-biomass ratio (0:100, 20:80, 50:50, 80:20 and 100:0) on hydrogen yield. Maximum hydrogen yield (8.1 mmol/g) and total gas yield (17.9 mmol/g) were obtained at optimal temperature and residence time of 525°C and 60 min, respectively. A change in the gas yield with variable plastic-to-biomass ratio showed synergistic effects between both feedstocks. The trend of catalytic performance towards improving hydrogen yield was in the following order: WO3–TiO2 (18.5 mmol/g) > KOH (16.9 mmol/g) > TiO2 (9.5 mmol/g) > ZrO2 (7.8 mmol/g) > WO3–ZrO2 (7.4 mmol/g).

Demographic variables play an important role in outcomes following revision total hip arthroplasty (rTHA). Surgical and in-patient variables as well as outcomes vary between indications for rTHA. The purpose of this study was to investigate the impact of the indication for the rTHA on costs and postoperative outcomes.This retrospective cohort analysis investigated all patients who underwent unilateral, aseptic rTHA at an academic orthopaedic specialty hospital who had at least 1-year postoperative follow-up. In total, 654 patients were evaluated and categorized based on their indication for aseptic rTHA. Demographics, direct and total procedure costs, surgical factors, postoperative outcomes, and re-revision rates were collected and compared between indications.Younger patients had the greatest leg length discrepancy (LLD) and older patients had the highest incidence of periprosthetic fracture (PPF) (P = .001). The greatest proportion of full revisions were found for LLD (16.7%) and head/polyethylene liner-only revisions for metallosis/adverse tissue reaction (100%). Operative time was significantly longest for LLD revisions and shortest for metallosis/adverse tissue reaction revisions (P.001). Length of stay was longest for periprosthetic fracture and shortest for LLD and stiffness/heterotopic ossification (P.001). Re-revision rate was greatest for implant failure and lowest for LLD. Total cost was highest for PPF (148.9%) and lowest for polyethylene liner wear (87.7%).Patients undergoing rTHA for indications such as PPF and aseptic loosening were associated with longer operative times, length of stay and higher total and direct costs. Therefore, they may need increased perioperative attention with respect to resource utilization, risk stratification, surgical planning, and cost-reducing measures.Retrospective Cohort Study.

Revision surgery is usually required for complications associated with total hip arthroplasty (THA). Significant morbidity can be associated with revision THA and thus some may only revise the liner of the original metal back component if it is found to be well fixed. We compare the long-term survivorship of cemented and uncemented head-liner THA exchange surgeries and possible causes.Between 2000 and 2018, we reviewed cases from our arthroplasty database who underwent THA revision for head-liner exchange. We stratified our cohort into 2 groups: cemented and uncemented liners. Patients were followed clinically and radiographically to determine survivorship of the exchanges for both cemented and uncemented liners. Implant survivorship was measured using a competing risk analysis considering death and patients lost to follow-up as competing risks.A total of 84 patients (85 hips) underwent head-liner exchange surgery during the study period (21 cemented and 64 uncemented liners). The mean follow-up time was 6.9 years, with 75.3% and 24.7% of patients having been revised due to non-dislocation and dislocation causes, respectively. Two cemented liners (9.5%) and 11 uncemented liners (17.2%) required revision. The survival analysis of all head-liner revision was 86.4% at 18 years. Survival estimates liner exchanges due to dislocation versus non-dislocation groups were 57.3% versus 82.7% respectively (P = .034).The present study shows improved survivorship of head-liner exchanges performed due to non-dislocation etiology compared to dislocation etiology, but no difference in survivorship between cemented and uncemented head-liner exchange.Level III.

Microplastic particles (MPs) are environmental pollutants that can cause varying levels of aquatic toxicity. Probiotics have been shown to reduce the negative effects of toxic substances. However, the protective effect of probiotics against the adverse effects of MPs has yet to be reported. The current study sought to determine the effects of the commercial probiotic AquaStar® Growout on polystyrene (PS)-MPs-mediated hepatic oxidative stress in Nile tilapia (Oreochromis niloticus). Fishes were assigned into four groups: the first group was the control, the second group was exposed to 1 mg/L of 0.5 μm PS-MPs, and the third and fourth groups were exposed to 1 mg/L of 0.5 μm PS-MPs and pre-fed with probiotics at levels of 3 g/kg and 6 g/kg diet, respectively. At the end of the experiment, probiotics administration reversed liver damage caused by the PS-MPs, reducing serum levels of malondialdehyde, aspartate aminotransferase, and alanine aminotransferase, and increasing the total antioxidant capacity. Furthermore, probiotics alleviated PS-MPs-induced oxidative stress by restoring antioxidant enzyme activities (superoxide dismutase, catalase, glutathione S-transferase, and glutathione peroxidase) and reducing oxidized glutathione and enhancing the redox state. Besides, probiotics supplementation decreased the transcriptional level of C-reactive protein and tumor necrosis factor-α following PS-MPs exposure. Furthermore, probiotics counteracted PS-MPs-associated reactive oxygen species production and mitogen-activated protein kinases (MAPKs) phosphorylation status. These findings suggested that probiotics could decrease liver damage caused by PS-MPs through their antioxidant properties and modulation of MAPK signaling pathways.

Pyrolysis is a leading technology to convert non-recyclable plastic waste to fuels or chemicals. As interest in the circular economy grows, the latter option has seemingly become more attractive. Once waste plastic is pyrolyzed to, for example, naphtha, however, additional steps are required to produce a polymer product. These steps consume additional energy and water and emit greenhouse gases (GHG). It is unclear whether this more circular option of non-recyclable plastics to virgin plastics offers environmental benefits, compared to their conversion to fuels. We therefore examine whether it is possible to determine the best use of pyrolyzing non-recyclable plastic - fuels or chemicals (low-density polyethylene (LDPE) as product)- from a life cycle perspective. We use recently published life cycle assessments of non-recycled plastics pyrolysis and consider two functional units: per unit mass of non-recyclable plastics and per unit product - MJ of naphtha or kg of LDPE. In the U.S., on a cradle-to-gate, per unit mass waste basis, producing fuel is lower-emitting than producing LDPE from pyrolysis. The opposite is true in the EU. But expanding the system boundary to the grave results in LDPE as the lower-emitting product in both regions. Naphtha and LDPE produced from non-recyclable plastics are less GHG-intensive than conventional routes to these products. Fossil fuel and water consumption and waste generation are all lower in the P2F case. Our results highlight that prioritization of P2P and P2F may depend on regional characteristics such as conventional waste management techniques and water scarcity.

There is little valid data available on managing infected total ankle arthroplasty (TAA).A single-center, retrospective evaluation from 20 patients with PJI (periprosthetic joint infection) of the ankle compared the bacteria isolated by preoperative arthrocentesis and intraoperative cultures to the pathogens of knee PJI. Long-term failure rates of irrigation and debridement (ID) and polyethylene exchange, revision arthroplasty, and arthrodesis were analyzed.The most common bacteria were Staphylococcus aureus and Coagulase-negative staphylococci. There was no significant difference when comparing the causing pathogens of PJI of the ankle with the knee. After a follow-up of 50,4 months, the long-term failure rate after ID and polyethylene exchange was 40%, and of revision was 9%.We concluded that the pathogenesis of PJI of the ankle and knee seems to be comparable. Regarding treatment options, we found that standardized techniques for PJIs of the knee have their limitations regarding infected TAA.

Lignosulfonate-based colloidal spheres were prepared from sodium lignosulfonate and cetyltrimethylammonium bromide (NaLS/CTAB) complex through electrostatic and hydrophobic self-assembly. Due to the stronger hydrophobicity and UV-blocking performance, NaLS/CTAB colloids were easier to be blended with HDPE than lignosulfonate, and therefore applied to UV-absorbing thermoplastics. Results showed NaLS/CTAB colloidal spheres had a particle size of 160 nm with a polydispersity index of 0.081. NaLS/CTAB molecules started to form spheres at critical water content of 64 vol% when the initial concentration of NaLS/CTAB in EtOH was 0.5 mg/cm

Neurotrophic keratopathy (NK) is a degenerative corneal disease with a loss of corneal sensitivity and impairment of corneal healing. Low dose insulin eyedrops have been shown to be a simple and effective treatment for refractory NK when the response to the usual treatment is incomplete. At present, there are no commercially available forms, and there is no data regarding the stability of these products as prepared by compounding pharmacies. In this work, we studied the physicochemical and microbiological stability of an insulin ophthalmic formulation obtained by mixing insulin lispro in artificial tears with a polyethylene and propylene glycol base. The stability of this 1IU/mL insulin ophthalmic formulation was analysed for 12 months in low-density polyethylene (LDPE) multidose eye droppers at 4°C. The studied parameters of physicochemical stability were: visual inspection, turbidity, UV spectral absorption, osmolality and pH. In addition, insulin and m-cresol concentrations and quantification of impurities (insulin covalent aggregates and insulin fragments) were studied thanks to the development of a new Size Exclusion Chromatographic method. For unopened eye droppers, all tested physicochemical parameters remained stable for 12 months at 4°C, and excellent microbiological stability was obtained. In conditions of simulated use, these parameters also remained stable for one month at 4°C, and no impact of potential temperature rises on the insulin and m-cresol concentrations in the insulin eyedropper was observed.

Surfactant molecules can change the hydrophobic nature of microplastic surfaces, thereby affecting the adsorption of heavy metals in the environment onto the microplastics. It is essential to explore the role of crack structure of microplastics in the adsorption of heavy metals, especially in the presence of surfactants. In this study, polyethylene (PE) and polypropylene (PP) were evaluated for Pb(II) adsorption and desorption mechanism in the presence of two surfactants: cetyltrimethylammonium bromide (CTAB) and sodium dodecylbenzenesulfonate (SDBS). The experimental results were analyzed using kinetics and the isothermal model fitting and spectrogram (FTIR, XPS). This study showed that the application of surfactants could greatly enhance the Pb(II) adsorption capacities of PE and PP by promoting Pb(II) into the fissures. The Pb(II), S, and N contents did not significantly decrease at different depths in the presence of surfactants, and the Pb(II) content without surfactants decreased with an increasing depth. The adsorption behavior was consistent with the Bangham channel diffusion model and the DR model, suggesting that the adsorption process was related to the pore structure of the microplastics. Furthermore, the release of Pb(II) from desorption using high concentration of surfactant solution was less than that of low concentration, it was difficult to release heavy metals primarily because of the crack structure of the microplastics, especially when more surfactant molecules entered the pores. This work contributes to a better understanding of the adsorption mechanism of heavy metals on microplastics in the presence of surfactants, which will better control the ecological risks of microplastics.

Molecular dynamics simulations have been performed to explore the underlying synergistic mechanism of pillared graphene or non-covalent connected graphene and carbon nanotubes (CNTs) on the mechanical properties of polyethylene (PE) nanocomposites. By constructing the pillared graphene model and CNTs/graphene model, the effect of the structure, arrangement and dispersion of hybrid fillers on the tensile mechanical properties of PE nanocomposites was studied. The results show that the pillared graphene/PE nanocomposites exhibit higher Young’s modulus, tensile strength and elongation at break than non-covalent connected CNTs/graphene/PE nanocomposites. The pull-out simulations show that pillared graphene by CNTs has both large interfacial load and long displacement due to the mixed modes of shear separation and normal separation. Additionally, pillared graphene can not only inhibit agglomeration but also form a compact effective thickness (stiff layer), consistent with the adsorption behavior and improved interfacial energy between pillared graphene and PE matrix.

Conventional polyethylene (CPE) was used widely in the past as a bearing surface in total hip arthroplasty (THA). As CPE THAs age and the revision burden continues to grow, it is increasingly important to understand the durability and failure mechanisms of this bearing material. Currently, such long-term data remain limited, particularly in younger, more active patients in whom wear issues are of greater concern.We retrospectively reviewed 90 hips (77 patients) that underwent primary THA with CPE bearings on cobalt chrome femoral heads at age ≤50 years at 20-year minimum follow-up (mean 21.6 [20-23]). We analyzed polyethylene wear rates, clinical outcomes (modified Harris Hip Score, University of California, Los Angeles Activity Score), and implant survivorship.Wear analysis revealed a median linear wear rate of 0.113 mm/y (95% CI 0.102-0.148) and a median volumetric wear rate of 41.20 mmWear-related issues developed at increasingly high rates after 15 years, suggesting the need for surveillance after this time. The long-term wear and survivorship data of this study may be used as a benchmark when evaluating the performance of contemporary bearings in young, active THA patients.

The analysis of microplastics (MP) becomes more difficult for smaller sizes, especially in complex matrices such as sediment of natural waters. In this work, we analyzed MPs in sediment using laser direct infrared (LDIR) imaging, a relatively new technique in environmental MP studies. Sediment samples were spiked with analytical surrogates (polyethylene spheres), and subjected to density separation, wet peroxide oxidation, calcite removal, and filtration. The extracted particles were coated on to a low-emissivity glass slide which was first examined on a stereomicroscope. Six slides (two sediment samples and four different blanks) were further analyzed using an Agilent LDIR system. Approximately 520 and 430 MP/g were found in the two samples, with diameter ranging 20–3384 μm and 84% being smaller than 100 μm. The increase in particle count with decreasing particle sizes followed a power law curve, suggesting that a large portion of the smaller MPs was generated by the breakdown of larger plastic pieces. Major polymers found in this work included polyamide, polyester, polytetrafluoroethylene, and polyacetal. Most MPs were fragments, while beads and fiber were also found. In the two sediment samples, 14% and 46% of the total particles, respectively, were composed of non-plastic micro-sized particles, including natural polyamide, cellulose, chitin, rubber, and “unknown”. Challenges, potential biases, and uncertainties are discussed. This work is the first application of LDIR imaging on MPs in natural sediment.

The consensus systematic risk stratification algorithm from the American Association of Hip and Knee Surgeons, the American Academy of Orthopaedic Surgeons, and The Hip Society summarizes clinical challenges in evaluation and treatment of metal-on-polyethylene total hip arthroplasty (THA) patients with adverse local tissue reaction (ALTR) due to mechanically assisted crevice corrosion (MACC), reviews up-to-date evidence, and identifies the areas for future research in order to provide a useful resource for orthopedic surgeons providing care to these patients. A painful THA has various intrinsic and extrinsic causes. ALTR is one of the intrinsic causes in patients with painful THA. The occurrence of ALTR due to MACC at modular junctions is likely to be multifactorial, including implant, surgical, and patient factors. Therefore, a systematic evaluation needs to involve a focused clinical history, detailed physical examination, laboratory tests, and imaging in order to identify potential differential diagnoses. There should be a low threshold to perform a systematic evaluation of patients with painful non-metal-on-metal THA, including patients with metal-on-polyethylene THA, and modular dual-mobility THA with the CoCr metal acetabular insert, as early recognition and diagnosis of ALTR due to MACC will facilitate initiation of appropriate treatment prior to significant adverse biological reactions. Specialized tests such as blood metal analysis and metal artifact reduction sequence magnetic resonance imaging are important modalities in evaluation and management of ALTR in patients with painful THA.

The rationale for advances in implant design is to improve performance in comparison to their predecessors. The purpose of this study was to compare a newer, self-pressurizing peripheral peg glenoid to a traditional polyethylene pegged glenoid through biomechanical evaluation and a retrospective radiographic and clinical review.Three testing conditions (uncemented, partially cemented, and fully cemented) were chosen to assess the 2 component designs in a foam block model. The number of hammer hits to seat the component, amount of time to seat the component, and resistance-to-seat were collected. The implants were then cyclically loaded following ASTM F2028-17 testing standard. Clinically, postoperative radiographs of patients with a self-pressurized glenoid component (n = 225 patients) and traditional glenoid component (n = 206 patients) were evaluated for radiolucent lines and glenoid seating at various timepoints. Clinical outcomes (American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, Simple Shoulder Test, and visual analog scale pain scores) and complications were recorded. The presence of radiolucent lines at the bone-cement interface was evaluated using the Modified Franklin Grade and the Lazarus grade.The self-pressurizing glenoid design required significantly more hammer hits than traditional glenoid designs in all groups tested (P .029). Moreover, the self-pressurizing design had significantly more resistance-to-seat than traditional components in both the uncemented and partially cemented group (P .002). No difference in resistance-to-seat was found between designs in the fully cemented group. The uncemented and partially cemented groups did not survive the full 50,000 cycles; however the self-pressurizing design had significantly less motion than the traditional design (P .001). No differences between component designs were found in the fully cemented group at 50,000 cycles. The self-pressurizing glenoid component had 0.005% radiographic radiolucent lines, and the traditional glenoid component had 45% radiographic radiolucent lines, with 38% of the radiolucencies in the traditional glenoid component group being defined as grade E. There were no progressive radiolucencies, differences in clinical outcomes, or complications at 2 years postoperatively.In the fully cemented condition, the 2 component designs had comparable performance; however, the differences in designs could be better observed in the uncemented group. The self-pressurizing all-polyethylene design studied has superior biomechanical stability. Clinically, the improved stability of the glenoid component correlated with a reduction of radiolucent lines and will likely lead to a reduction in glenoid component loosening.

The long-term failure modes of total hip arthroplasty (THA) in adult patients who had childhood infection have not been documented. The purpose of this study is to analyze the longer term clinical and radiographic results, prevalence of osteolysis, and survival rate of THA.We reviewed the results of 142 patients (145 hips) (mean age 41.9 years). The age of the patients at the time that the infection was contracted was an average of 7.1 years (range 1-11). The average interval between active infection and THA was 34.5 years. All but 2 hips (1 patient) had a quiescent period of infection of more than 10 years. The average duration of follow-up after THA was 31.5 years (range 25-38).All but 2 hips with more than 10 years of quiescent infection had no recurrence of infection. The remaining 2 hips in the 1 patient with only 7 years of quiescent infection had a recurrence of infection. Seventy-eight of 145 hips (54%) underwent isolated cup revision for loosening, or osteolysis, or dislocation. Thirty (21%) femoral components were revised for aseptic loosening and/or osteolysis. The Kaplan-Meier survivorship curve at 31.5 years showed that the survival rate of the acetabular component was 46% (95% confidence interval 39-74) and that of the femoral component was 79% (95% confidence interval 73-89).Contributing factors to the high failure rate of THAs were less than optimal prostheses and poor quality of polyethylene during the time period of this study.

Survivorship of total hip arthroplasty (THA) in younger patients is concerning given the inverse relationship between age and lifetime risk for revision. The purpose of this study is to determine if risk of revision has improved for patients aged 55 years or younger who undergo primary THA using modern polyethylene liners.A retrospective review identified 2,461 consented patients (2,814 hips) with minimum 2-year follow-up who underwent primary THA at our institution between September 2007 and August 2014 using components from a single manufacturer (Zimmer Biomet), all with vitamin E-infused highly crosslinked polyethylene acetabular inserts. There were 561 patients (643 THA; 23%) aged 55 or younger and 1,900 (2,171 THA; 77%) older than 55.Mean follow-up was 5.0 years for both groups. There were more male patients in the younger (55%) than older (41%) group. Body mass index (BMI) was higher in younger patients independent of gender. Improvement in Harris hip score (HHS) was similar between groups. Kaplan-Meier survival to endpoint of all cause revision was similar between groups at 12 years (P = .8808) with 97.5% (95% CI: ±0.7%) for younger versus 97.1% (95% CI: ±0.6%) for older patients. Most frequent reason for revision overall was periprosthetic femoral fracture (21; 0.75%); univariate analysis revealed risk factors were female gender (P = .28) and age ≥65 years (P = .012).Use of modern polyethylene, such as vitamin E-stabilized highly cross-linked, liners during THA may improve survivorship in younger patients undergoing THA. Younger patients undergoing primary THA with highly cross-linked polyethylene liners had no increased rate of revision at mid-term follow-up.

Oxidized zirconium (OxZi) femoral heads combine the decreased abrasive properties of ceramics with the toughness of metal alloys to lower wear and increase the durability of total hip arthroplasty. The purpose of this study was to compare the 10-year polyethylene wear rates between OxZi/XLPE and cobalt chrome (CoCr)/XLPE articulations.A radiostereometric analysis (RSA) was performed on two cohorts of 23 patients who underwent total hip arthroplasty using either OxZi/XLPE or CoCr/XLPE at a minimum of 10-year follow-up. Cohorts were matched for age, gender, body mass index (BMI), and diagnosis. Polyethylene wear was measured using RSA to determine total and steady-state wear rates for both cohorts. Preoperative and postoperative patient-reported outcome measures (SF12, HHS, and Western Ontario and McMaster Universities Arthritis Index scores) were compared.The mean total head penetration rate was found to be statistically different between the entire cohorts (OxZi 0.048 ± 0.021 mm/y, CoCr 0.035 ± 0.017 mm/y, P = .02) but not when 28-mm heads only (OxZi 0.045 ± 0.016 mm/y, CoCr 0.034 ± 0.017 mm/y, P = .066) were directly compared. The mean steady-state wear rate was not significantly different between the entire cohorts (OxZi 0.031 ± 0.021 mm/y, CoCr 0.024 ± 0.019 mm/y, P = .24) or 28-mm head cohorts (OxZi 0.028 ± 0.019 mm/y, CoCr 0.024 ± 0.019 mm/y, P = .574). Outcome measures showed no statistical difference except for the Harris Hip Score where the OxZi cohort demonstrated higher median scores.Using RSA to evaluate the 10-year in-vivo head penetration, there was no statistically significant difference in steady-state wear rates between OxZi and CoCr articulations. Both bearing combinations demonstrated wear rates well below the threshold for osteolysis.

Gadolinium (III)-based T1 contrast agent have been widely used in clinical MRI. In this study, salicylic acid-gadolinium chelate was prepared via directly coordination reaction of gadolinium ion and salicylic acid. Then, three polyethylene glycols with different molecular weight were modified on the surface of salicylic acid-gadolinium by simple chemical coupling to construct three core-shell structural Gd based composites. The SEM and TEM characterization results show that the composite is a spherical particle with a diameter of about 100–200 nm. The longitudinal relaxation rate r1 of the Gal-PEG-2000 is 11.097 (mmol/L)–1/s, and the ratio of r2/r1 is as low as 2.53. The composite shows good liver and intestines MRI performances after being used in in vivo imaging, showing a good prospect of biological application.

Highly cross-linked polyethylene with vitamin E (VE-HXLPE) has shown superior tribological properties and has been rapidly adopted in total hip arthroplasty. However, the majority of studies compare VE-HXLPE to conventional or moderately cross-linked polyethylene using standard femoral head sizes. This study's purpose was 2-fold: (1) compare radiographic femoral head penetration (FHP) between VE-HXLPE and HXLPE and (2) evaluate FHP in large femoral heads ≥40 mm.One hundred forty-two consecutive primary total hip arthroplasties using ceramic femoral heads (n = 84 VE-HXLPE; n = 58 HXLPE) in a single implant system were retrospectively reviewed. FHP was measured radiographically utilizing Martell method at 4-week, 1-year, and latest radiographs. FHP, cup position, and demographic variables were compared between VE-HXLPE and HXLPE liners.Median linear FHP was lower for VE-HXLPE compared to HXLPE during the initial "bedding-in" period between 4-week and 1-year (0.383 vs 0.551 mm, P = .650) and between 1-year and latest follow-up (0.131 vs 0.270 mm/y, P = .636) although without statistical significance. Acetabular cup inclination and anteversion did not influence linear or volumetric FHP (P ≥ .204). Large femoral heads (≥40 mm) were predictive of higher FHP during the early bedding-in period (P ≤ .025) but did not have an effect beyond 1 year in multivariate regression with numbers available. No radiographic osteolysis was observed in any case.These findings support others that VE-HXLPE is the optimal polyethylene bearing surface to minimize FHP during the bedding-in period and beyond. Surprisingly, large ceramic femoral heads appear to influence FHP during the initial bedding-in period but do not increase FHP beyond 1 year. Further longer term follow-up remains warranted.III.

Ultracongruent bearings are increasingly utilized in total knee arthroplasty (TKA); however, implications of surgical technique on knee kinematics and outcomes with these bearings are not well understood. This study's purpose was to evaluate the relationship of 3-dimensional knee kinematics and patient-reported outcome measures (PROMs) in a dual-pivot congruent bearing TKA with and without posterior cruciate ligament (PCL) release.Forty patients undergoing TKA with an asymmetric ultracongruent bearing were prospectively enrolled for gait analysis preoperatively and 4 months postoperatively. Three-dimensional gait analysis was performed utilizing infrared motion capture. Knee kinematic data and PCL disposition were analyzed for correlations with PROMs.The PCL was fully released in 52.5% (21/40) of cases. Greater maximum anteroposterior femoral translation correlated with lower Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (rho = -0.596, P = .012), greater Knee Society Score pain with level walking (rho = 0.411, P = .101), and greater Knee Society Score pain while climbing stairs (rho = 0.469, P = .058) at 4-month follow-up. The PCL-release group was associated with greater maximum femoral anteroposterior translation (9.8 vs 5.5 mm, P = .053) and greater maximum internal tibial rotation (-6.2° vs -3.0°, P = .040), supporting a more anterior-based position of the medial condyle. The PCL released group had lower median Knee Injury and Osteoarthritis Outcome Score for Joint Replacement scores (70.7 vs 76.3, P = .031) and reported that their knees "sometimes or always" feel normal less frequently (81.8% vs 92.3%, P = .576).With this asymmetric ultracongruent bearing TKA, preservation or partial titration release of the PCL, as opposed to full PCL release, appears to minimize deleterious anterior femoral translation and internal tibial rotation, which is correlated with optimized patient-reported outcomes.II.

Mobile bearing designs are intended to reduce wear, but mixed results were reported from retrieval analyses. Postmortem evaluation (PM) provides the opportunity to assess polyethylene damage in successful implants. We compared damage patterns, MRI presentation, and histology between mobile-bearing and fixed tibial inserts retrieved postmortem and compared these results to our prior findings from implants retrieved at revision.Eleven postmortem knees with rotating platform (RP) implants and 13 with fixed bearing (FB) implants were examined. All were MRI scanned, and tissue samples were collected from standardized regions for histology. Polyethylene inserts were subjectively scored to assess articular, backside, and PS post surfaces for damage modes and severity.Average duration of implantation was 9.3 years (1.7-19.6 years). Surface burnishing was the most common polyethylene damage mode. Average damage scores were higher for RP (53.4) compared to FB inserts (34.4) due to greater backside damage (13.4 for RP vs 1.4 for FB). A minimal difference in damage was observed on the articular surfaces (37.4 RP vs 30.0 FB). Mild innate macrophage reactions were seen in 8 (72.7%) RP and 5 (45.5%) FB specimens. Polyethylene particles were identified in 7 (63.6%) RP and 3 (27.7%) FB specimens.Postmortem inserts showed low damage levels and mild tissue reactions compared to those reported for implants removed at revision arthroplasty. Nonetheless, trends in comparing RP and FB inserts were consistent with those seen in retrieval analyses, demonstrating the usefulness of retrieval studies in capturing performance differences among TKA designs.

Knee-Society Meeting, ELECTR NETWORK, SEP, 2021; Background: Unicompartmental knee arthroplasty (UKA) is a procedure with low morbidity and fast recovery. Anatomic implants or robotic-assisted UKA has been proposed to improve outcomes with precise positioning. Femoral component position (FCP) relative to the tibial insert could be a factor influencing the contact stresses. We aimed to evaluate the effect of the FCP relative to the tibial insert on clinical outcomes and stress distribution after medial UKA. Methods: Sixty-two medial fixed-bearing UKAs were evaluated at a minimum two-year follow-up using the Knee Society Score. Postoperative radiological evaluation performed on frontal X-rays classified the FCP relative to the tibial insert into the following: group M (medial), group C (central), and group L (lateral). A finite element model was developed to evaluate the biomechanical effects of the FCP relative to the tibial component. Results: The postoperative radiological evaluation showed 9 cases in group M, 46 cases in group C, and 7 cases in group L. The maximum knee flexion angle and the 2-year postoperative ``symptom'' and ``patient satisfaction'' scores of the Knee Society Score were significantly higher in group C. Compared with central positioning, a shift along the mediolateral axis leads to a displacement of the contact pressure center. Conclusion: The FCP relative to the tibial insert may increase patient outcomes at a minimum follow-up of two years after fixed-bearing medial UKA. Accordance between FCP and contact stresses on the polyethylene insert could be a contributing factor of long-term survival of UKA. (C) 2022 Elsevier Inc. All rights reserved.

Droplet-based microfluidic technology can be utilized as a microreactor to prepare novel functional monodisperse microcapsules. In this study, a droplet-based microfluidic chip with surface modification, which allowed the one-step preparation of double emulsion microcapsules. An O/W/O double emulsion using polyethylene (glycol) diacrylate (PEGDA) solution as the intermediate water phase was prepared by regulating the hydrophilicity and hydrophobicity of the chip surface, with PEGDA microcapsules prepared using UV polymerization. And then anti-tumor drug paclitaxel and neurotoxin 6-OHDA were encapsulated in microcapsules for drug and toxicology evaluation, respectively. Compared to controls, drug-loaded microcapsules caused a significant increase in the death rate of PC12 cells. This indicates that the obtained drug-loaded microcapsules could be used in drug evaluation and potentially in drug screening and delivery.

All-solid-state lithium batteries (ASSLBs) employ high-capacity lithium (Li) metal as the anode and exhibit a higher energy density than that of conventional Li-ion batteries. However, the problems arose from the Li dendrites induce severely parasitic reaction between Li and electrolytes, leading to low coulombic efficiency (CE) and poor cyclic stability. Herein, a poly(vinylidene-co-hexafluoropropylene)/lithium nitrate (PVDF-HFP/LiNO3, marked as PFH/LN) artificial layer is employed to modified Li and achieve high CE ASSLBs with polyethylene oxide-Li6.4La3Zr1.4Ta0.6O12 (PEO-LLZTO) electrolyte. LN serves as a functionalized additive to facilitate the formation of a robust solid electrolyte interface (SEI), efficiently suppressing the formation of Li dendrites. Additionally, LN as a “binder” effectively links PFH with Li, providing good contact. PFH possesses high mechanical strength and moderate flexibility, which can not only physically inhibit the growth of Li dendrites, but also maintain the structural integrity of artificial layer over long-term cycles. Finally, Li/Li cells with such artificial layer demonstrate ultralong cycle life of 1800 and 1000 h under 0.2 and 0.4 mA cm–1, respectively. Furtherly, high CE can be achieved when applied in both LiFePO4 full cells and Li-Cu half cells. This work offers a facile and efficient strategy to greatly promote CE in PEO-based ASSLBs.

Aseptic loosening from implant-associated osteolysis in reverse shoulder arthroplasty (RSA) may contribute to premature implant failure. Although articular side polyethylene (PE) damage has been well documented in the literature, no studies to date have investigated backside wear in RSA. The aims of this investigation were to (1) document and compare the damage between the backside and articular surface in explanted RSA components, (2) assess whether certain quadrants have a greater propensity for damage, and (3) report the most common mode(s) of backside PE damage.Twenty-one RSA humeral liners retrieved during revision procedures between 2005 and 2014 were included for analysis. The mean time between implantation and extraction was 16 months (10 days-88 months). Diagnoses at the time of revision included dislocation (10), infection (4), mechanical failure (3), loosening (2), and unknown (2). Liners were examined under light microscopy (×10-30 magnification) and damage on the articular and backside of the liner surface was graded using the modified Hood score. The location and damage modality were compared between the articular side and backside of the implant.Damage was noted on the articular surfaces of all 21 liners and on the backside surface of 20 liners. The total damage in all the quadrants was higher on the articular surface than on the backside of the component, with a mean difference in total quadrant damage scores of 11.74 ± 3.53 (P.001). There was no difference in damage among the quadrants on the backside (P = .44) or the articular surface (P = .08). The articular side exhibited greater scratching, abrasion, and surface deformation than the backside (P.001).This short-term retrieval study demonstrated that backside PE damage occurs on the humeral component of RSA implants. There was greater damage to the articular side of the liner but wear to the backside was present in almost all liners. The clinical importance of backside wear in RSA and its overall contribution to PE particulate disease and osteolysis needs further investigation.

To increase the low yield and selectivity of aromatic hydrocarbons during the biomass pyrolysis process, we torrefied the biomass and then co-pyrolyzing with plastics such as high-density polyethylene (HDPE), polystyrene (PS), ethylene-vinyl acetate (EVA) and polypropylene (PP) and also single and dual catalyst layouts were investigated by Py-GC/MS. The results showed that non-catalytic fast pyrolysis (CFP) of raw bagasse (RBG) generated no aromatics. After torrefaction non-CFP of torrefied bagasse (TBG) generated low aromatic yield. Indicating that torrefaction would enhance the proportion of aromatics during the pyrolysis process. The CFP of TBG200°C and TBG240°C over ZSM-5 produced the total aromatic yield of 1.96 and 1.88 times higher, respectively, compared to non-CFP of TBG. Furthermore, the addition of plastic could increase H/Ceff. ratio of the mixture, consequently, increase the yield of aromatic compounds. Among the various torrefied-bagasse/plastic mixtures, the CFP of TBG/EVA (7:3 ratio) mixture generated the highest the total aromatic yield of 7.7 times more than the CFP of TBG alone. The dual catalyst layout could enhance the yield of aromatics hydrocarbons. The dual-catalytic co-pyrolysis of TBG200°C/plastic (1:1) ratio over USY/ZSM-5, improved the total aromatics yield by 4.33 times more than the catalytic pyrolysis of TBG200oC alone over ZSM-5 catalyst. The above results showed that the yield and selectivities of light aromatic hydrocarbons can be improved via catalytic co-pyrolysis and dual catalytic co-pyrolysis of torrefied-biomass with plastics.

In this study, the catalytic co-pyrolysis (CCP) of wet-torrefied bamboo sawdust (TB) and linear low-density polyethylene (LLDPE) over zeolites was carried out using the thermogravimetric analyzer. The analysis was carried out at four different heating rates (5–40 °C min−1) and under an inert (Ar) atmosphere. Four degradation stages were observed in the CCP of TB and LLDPE blends, the first stage being moisture removal. The peak decomposition temperature of catalytic pyrolysis (CP) of LLDPE over FAU was reduced by 251 °C as compared to that over HZSM-5 and the enhancement can be attributed to the topology of HY. The activation energies were calculated using isoconversional models: Kissinger–Akahira–Sunose model (KAS), Ozawa–Flynn–Wall model (OFW), and Friedman model (FM). The average activation energies (Eα) of the blends TBL3:1, TBL1:1, and TBL1:3 (TBL: Blend of torrefied biomass and LLDPE) were 171, 128, and 117 kJ mol−1, respectively, using the KAS model. The Eα of the blends was much lower as compared to that of TB, indicating a clear synergism. A multistep mechanism was observed in both CP of individual samples and CCP of blends, as analyzed by Criado's master plot. For example, the CCP of TBL1:3 followed geometric (volume) contraction (R3) and first-order reaction models at low and high conversions, respectively.

An organic/inorganic hybrid coating consisting of molecular sieve (MS)/sulfonated melamine formaldehyde condensate (SMF) is fabricated on the polyethylene (PE) separator by a simple dip-coating process. The MS/SMF coating with high polarity enhances the electrolyte uptake of PE separator, and therefore favors higher ionic conductivity and Li+ transference number of separators. By regulating the ratio of MS/SMF, much higher Li+ transference number up to 0.5 can be obtained compared with the original PE separator (0.25). The PE separator possesses highest effective Li+ ionic conductivity when the ratio of MS/SMF is 3:1, which promotes more uniform Li+ deposition on the lithium metal surface for excellent lithium plating/stripping cycling stability up to 1000 h without any signs of short-circuit. Moreover, the functional PE separator possesses excellent H2O and HF capturing ability due to strong adsorption of MS and SMF for H2O and the scavenging of SMF for HF. The MS-SMF@PE separator-employed LiCoO2/Li unit cell shows superior C-rates capability and cycling performance, and no obvious lithium dendrite growth is found on the surface of lithium metal anode after cycling.

Polypropylene (PP) and polyethylene (PE) play central roles in our daily life. However, their immiscibility presents a major hurdle in both industry and academia when recycling them into alloys with favorable mechanical properties. Moreover, typical compatibilizer-enabled approaches are limited due to increased environmental concerns. Herein, inspired by a traditional Chinese technique, we report a facile, industry-scale methodology that produces a PP/PE binary blend with a highly ordered honeycomb nanostructure without any additives. Due to its nanostructure, the blend exhibits enhanced tensile properties in comparison with the parent components or with a sample prepared using an internal mixer. This approach has potential for applications not only in immiscible polymer blending, but also in non-sorting, compatibilizer-free waste plastics recycling. Through this technique, we expect that an environmentally friendly and sustainable plastic wastes recycling avenue can be found, and great economic benefits can be gained.

Recycling of plastic waste is an effective way that could prevent our planet from drowning in plastic pollution. The work presents chemical vapor deposition (CVD) growth of single-walled carbon nanotubes (SWNTs) from plastic polymers, including low-density polyethylene (LDPE) and polypropylene (PP). The successful synthesis of SWNTs from the polymers is attributed to the robustness of the designed cobalt catalyst supported by porous magnesia (Co-MgO), the porosity of which constrains the mobility of reduced Co nanoparticles, thus facilitating the nucleation of small diameter SWNTs. In addition, the approach is extended for catalyzing the production of SWNTs from plastic wastes, such as food packaging film and mask melt-blown filter. The proof-of-concept advance demonstrates the potential of plastic waste itself as feedstock for the production of high-value carbon nanomaterials.

Introduction Modular component exchange can limit morbidity by retaining well-fixed hip arthroplasty components but dislocation has been a relatively frequent postoperative complication. This study evaluated the effect of surgical approach on dislocation rate in a modern revision cohort. Methods From 2010 to 2020, 248 aseptic head and liner exchanges were performed at a single institution including 54 done via the direct anterior (DA), 80 via the direct lateral (DL), and 114 via the posterolateral (PL) approach. The mean patient age at revision was 64.9±10.4 years and 50% (123/248) were performed among males. Indications for revision included 140 (56%) for polyethylene wear, 68 (27%) for failed metal-on-metal components, and 40 (16%) for instability. The mean follow-up after revision was 2.3 years. Results Thirty (12%) patients dislocated at a mean of 0.6 years (range, 0.01 to 4.6 years) postoperatively. The dislocation rate stratified by revision approach was 17% (9/54) for the DA, 6% (5/80) for the DL, and 14% (16/114) for the PL approach (p=0.13). Hips revised by the DA that dislocated were more abducted (51±8 vs. 45±8, p=0.05) and more anteverted (26±9 vs. 20±7, p=0.08) than non-dislocators. Among all 248 hips, cups with more than 48 degrees of abduction were 2.6 times more likely to dislocate (p=0.01). Head diameter, neck length, patient age, and sex were not associated with dislocation (p≥0.20). Discussion and Conclusion Dislocation remains a common complication after head and liner exchange regardless of approach. Cup position contributes to postoperative instability and must be critically evaluated during preoperative planning.

In households, considerable costs are related to energy losses, which are a consequence of maintaining comfortable living temperatures. Improved isolation and utilization of energy harvesting devices is the key to reducing energy losses and the related costs. Polymeric solar absorbers are cost-effective solar energy harvesters that can significantly reduce the energy cost for individual households. One of the concerns related to polymers is their flammability. To mitigate the flammability risk, the present work explores the development of solar absorber paints with flame-retardant properties. Bridged 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivatives (NED and PHED) in concertation ranges of 10–15 wt% were used in a polyurethane-based matrix to demonstrate the effect of additives on the fire retardancy of the material. Additionally, the rheological and thermal properties of the composite materials were evaluated and described. Furthermore, aluminium and PPS (polyethylene sulphide) substrates were coated with solar absorber paint based on a 15% FR (fire retardant) additive formulation, for which the thermal stability at 150 °C for 655 h was evaluated. It was discovered that PHED is more compatible with the polyurethane matrix than NED, and as expected, a greater amount of FR additives resulted in improved flame retardancy. The long-term stability of absorber paint coatings on Al and PPS was also successfully confirmed by confirming stable solar absorptance and thermal emittance. In future prospects, we believe that the flame retardancy of polyurethane-based coatings could be further improved, and the utilization of covalently bonded FRs should also be considered.

A highly sought-after objective of Space Agencies is the development of additive manufacturing (AM) technologies and of multifunctional materials, key elements to future exploration and colonization of Moon and Mars. The 3D printing process via fused filament fabrication (FFF) is increasingly viewed as an interesting approach for the in-situ manufacturing of buildings and items using regolith as a feedstock material, enabling the necessary repair and recycling capabilities to ensure crew safety. In this work, we investigate the radiation shielding properties and the FFF 3D printing process of polyethylene-based composites filled with Martian regolith. The on-line tool for the assessment of radiation in space (OLTARIS) software developed by NASA was used to assess the radiation shielding effectiveness of polyethylene (PE)/regolith (RG) composites in the Martian radiation environment. A basalt powder with chemical composition similar to that of Mars soil was used as Martian regolith simulant in the 3D printing process. Differential scanning calorimetry (DSC) was used to determine the melting properties and crystallization degree of PE/RG composites at different RG concentrations, in order to analyze the effect of the simulant on the process parameters of filament extrusion and 3D printing. Low-impact Izod tests were also performed, with all PE/RG composites showing improved impact strength with respect to neat PE. Based on the DSC and Izod tests results, filaments of PE/RG composites were fabricated and used to 3D-print samples for tensile tests and 3-point bending tests. Results demonstrate the radiation shielding effectiveness of PE/RG composites and the capability of 3D-printers based on FFF to successfully manufacture components made of PE/RG composites starting from extruded filaments.

The extremely increasing amount of plastic waste due to the development of human society, economics and urbanization is an emergency task that must be urgently handled in order to reduce environmental problems. Although the plastic wastes can be converted to alternative liquid fuels through pyrolysis process, the compositions in the pyrolysis oil depended on the chemical structure of raw materials and pyrolysis condition affect its quality. Thus, this research aimed to comparatively investigate the production of alternative liquid fuels obtained from mixed plastics containing polystyrene (PS)/polyethylene terephthalate (PET)/polyethylene (PE)/polypropylene (PP) at 20/5/35/40 (w/w) via non-catalytic cracking (under N2 atmosphere), non-catalytic hydrocracking (under H2 atmosphere), and catalytic hydrocracking over 10 wt% Ni/SBA-15 catalyst conducted at an atmospheric pressure and 650 °C for 1 h. The product yields and chemical compositions (paraffins, olefins, aromatics and PAHs) in the liquid products generated from these processes were investigated and also compared to ones obtained from the non-catalytic processes of each plastic. Herein, the characteristics of 10 wt% Ni/SBA-15 catalyst was analyzed by N2-adsorption/desorption, X-ray diffraction (XRD), and H2-temperature programmed reduction (H2-TPR). The results indicated that the non-catalytic processes of PS provided the highest content of oil and wax product (ca. 92 wt%). Whereas, the non-catalytic hydrocracking of the mixed plastics gave the lowest one (ca. 69 wt%). However, the catalytic hydrocracking over 10 wt% Ni/SBA-15 catalyst (2.5 – 10.0 wt% based on the mixed plastics) could suppress the cracking and yielded the higher amount of oil and wax to ca. 76–80 wt%. To consider the chemical compositions in the liquid phase, the PAHs formation was relied on the aromatic structure in the feedstocks. The liquid product derived from the non-catalytic processes of PS contained the highest amount of PAHs compounds (2622–2926 ppm) followed by the mixed plastics. When the 10 wt% Ni/SBA-15 catalyst was applied to the catalytic hydrocracking of the mixed plastics, the amount of PAHs in the liquid product decreased from 1621 ppm to ca. 1000 ppm (30 – 40% PAHs reduction) without the reduction of heating value when compared to one obtained from the non-catalytic processes.

The establishment of a method of separation of materials from Tetra Pak waste to obtain products for use as raw material, fuel or other purposes was investigated in this study. First, the feasibility of hydrothermal treatment for the production of a solid fuel (hydrochar) and solid fraction formed by polyethylene and aluminum, called composite was analyzed. The results indicated that hydrothermal treatment performed at 240 ◦C yield the formation of hydrochar with good properties for its use as fuel and a composite of polyethylene and aluminum. The best conversion and separation of the cardboard and polyethylene/aluminum were obtained using 120 min as operating time. Then, the recovery of the aluminum fraction from the composite by using spent olive oil waste was studied. A partial separation of the composite layers (polyethylene and aluminum) was accomplished with improved aluminum purity for higher operating temperatures. Finally, the operating conditions of the pyrolysis process for the production of a solid (char) and high purity composite (aluminum) were optimized. The characterization results indicated that both char and aluminum resulting from the pyrolysis of the Tetra Pak at 400 ◦C still have a significant amount of polyethylene while higher purity levels of aluminum can be obtained at temperatures equal of higher than 500 ◦C.

Due to their likeness in composition to natural tissues, synthetic hydroxyapatite (HA) nanoparticles have good biocompatibility, bioactivity, and osteoconductivity and have large applicability in a wide range of fields such as in tissue replacement, drug/gene delivery carriers, and biocompatible coatings. In this study, we synthesize hydroxyapatite by double decomposition method, we carried out the reactions in a water–ethanol medium at pH = 12 and room temperature. Its ceramization and the effect of sintering temperature and forming technique of this ceramic on the chemical and structural behavior, and compare it to natural hydroxyapatite extracted from bovine bones. According to the results obtained from the structural and morphological characterization techniques, the elaborate hydroxyapatite is similar to natural hydroxyapatite and can be used as a bone substitute. The HA powders obtained are modified by different levels of polyethylene. The characterization by different techniques (infrared; DRX; SEM, etc.). All the results of this work allow on the possibility of using these materials in the biomedical field such as in tissue replacement, drug/delivery carriers.

When utilised in arthroplasty applications, ultra-high-molecular-weight polyethylene (UHMWPE), the gold standard material for artificial joints, creates wear debris. The life of UHMWPE joints is generally restricted to 15–20 years due to unfavourable interactions of wear debris with surrounding tissues. Various attempts have been made in recent decades to enhance the material's wear resistance and performance. This study looks at the changes that have been made to increase its mechanical characteristics and wear resistance. Functionalization techniques, enhanced surface or bulk properties, and their various applications in medical implant fields (total hip arthroplasty, bone tissue engineering, joint implants) have all been extensively studied. A descriptive study of pure UHMWPE and its composite has been conducted in order to functionalize the features of medical implants.

The disposal of non-biodegradable materials like polyethylene, tetrapak etc have been a severe threat to the surrounding environment especially in developing/ under developing countries. Out of that, the polyethylene materials are commonly used to pack food and essential commodities like milk, curd, ghee, oil, snacks etc. After usage of these products, the polyethylene packs are left as solid wastes which was disposed either incineration or by dumping as landfills. An effort to find useful application of those polyethylene material wastes is on one side. In other side the existing pavements are not able to withstand the increase in traffic loads and thereby results to premature failure causing various pavement distress. In these aspects, to explore new suitable and sustainable alternative bituminous mix is a demanding need. In order to address both these issues, the present study investigated the suitability of polyethylene wastes in to the bitumen concrete mix. For this study, the polyethylene wastes of milk packets are shredded to a varying length of 1.5 cm, 3 cm, and 6 cm are mixed in dry pieces with the heated aggregates at temperature of 150–170 °C. Marshall specimen of bituminous concrete with and without shredded polyethylene wastes are prepared and tested as per the standard procedure. The Marshall characteristics like Marshall Stability, flow value, unit weight, air voids etc are determined. Based on the performance evaluation, all the Marshall characteristics of the mix are found to be satisfied for the utilization of shredded polyethylene waste strip 3.0 cm at 0.5% by weight of aggregate for both bitumen content 5% and 6%.

Biologically synthesized surfactant are commercially used in various biotechnology sectors as cosmetic, cleaning, and agriculture products. In this study, Bacillus paramycoides was isolated as new bacterial strain from plastic disposal site of Banasthali Vidyapith (Rajasthan) for producing lipopeptide biosurfactant. Surface tension, emulsification index, oil-displacement are some primary screening methods done to validate the production of biosurfactant. The emulsification analysis elucidated at 62.50% and reduction of surface tension noticed at 33.10 mN/m. The nano-encapsulation of this biosurfactant onto silver nanoparticles had efficiently improved its ability for biodegradation of polyethylene. UV sterilized polyethylene films were treated with biosurfactant mediated silver nanoparticles and its maximum degradation was observed within 70 days. The synthesized silver nanoparticles were characterized by UV spectrum, zeta size potential, scanning electron microscope analysis. The total weight loss of low-density polyethylene (cling films) and high-density polyethylene (grocery bags) was observed 36.30% and 31.11%, respectively after treatment with silver nanoparticles for these lipopeptide biosurfactant. The higher degree of biodegradation rate of LDPE and HDPE polyethylene after treating with silver nano-biosurfactant might be due to their high degree of biocompatibility and stability. These nano-biosurfactant could be effectively used for biodegradation of plastic pollutant at large scale.

Plastic waste is accumulated in recent years, causing environmental problems, particularly in developing nations. Recycling this waste as building materials is considered as a feasible solution to the environmental issue, but it is also a feasible solution to the issue of building economic design. This research aims to study the possibility of using plastic waste in the manufacture of unconventional bricks that are light in weight, environmentally friendly, inexpensive, and as an alternative to traditional bricks made from fossilized clays for use in the construction industries. In this paper, we use the remnants of medical syringes made of low-density polyethylene and two types of additives were added sawdust and sand in different proportions. The melting and moulding process was used in manufacturing. Testing has been conducted to identify hardness, density, water absorption, compressive strength and also to determine morphology properties by FTIR and SEM. The results showed that bricks made of plastic and sawdust gave a high compressive strength of 66Ϻpa at 20% of sawdust higher than bricks made of plastic and sand with a value of 61Ϻpa at 60% of sand. In both cases, they gave a higher compressive strength than ordinary bricks, as well as a very low absorption rate. The density was very low, especially with sawdust, where the highest value was 0.8985 g/cm3of pure polymer, and for sand, it was 1.4321 g/cm3 at 60% of sand and it gave good hardness values. The FTIR results showed that there is no chemical reaction, but only a physical reaction between the polymer and the additives, and through SEM, it was observed that there is homogeneity between the polymer and the additives. As a result, the study presents a new line of investigation into the sustainable recycling of the circular economy of waste thermoplastics.

Natural fibres now a days replacing the conventional structural materials such as Aluminium, steel, wood etc. with their excellent weight to strength ratio and with their high mechanical properties. In this present investigation hybrid composites were fabricated using Hand layup process using the natural fibres such as Banana, Coconut, Jute and Cotton fibres reinforced with Polyethylene at different weight proportions of 5, 8, 10, 12, 15, 18, 20 wt%. Tests such as water absorption, flexural rigidity, tensile, hardness and few other mechanical tests were conducted on the hybrid natural fibre reinforced composites. Among the hybrid composites the coconut fibre with 20 wt% and banana fibre with 18% shows high tensile strength with 56.4 N/mm2 and 54 N/mm2 and flexural strength. Water absorption is less in the hybrid composite with coconut and cotton fibres as reinforcements and gains mass of 5gm and 7gm.