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Background: Chemoradiotherapy (CRT) modulates the tumor immune microenvironment of multiple cancer types, including esophageal cancer, which potentially induces both immunogenicity and immunosuppression by upregulating the presentation of tumor-specific antigens and immune checkpoint molecules in tumors, respectively. The prognostic effects of immune modification by CRT in esophageal squamous cell carcinoma (ESCC) remain controversial because of the lack of detailed immunological analyses using paired clinical specimens before and after CRT. We aimed to clarify the immunological changes in the tumor microenvironment caused by CRT and elucidate the predictive importance of clinical response and prognosis and the rationale for the necessity of subsequent programmed cell death protein 1 (PD-1) inhibitor treatment. Methods: In this study, we performed a comprehensive immunological analysis of paired biopsy specimens using multiplex immunohistochemistry before and after CRT in patients with unresectable locally advanced ESCC. Results: CRT significantly increased the intra-tumoral infiltration and PD-1 expression of CD8+ T cells and conventional CD4+ T cells but decreased those of regulatory T cells and the accumulation of tumor-associated macrophages. Multivariate analysis of tumor-infiltrating T-cell phenotypes revealed that the density of PD-1+CD8+ T cells in the tumor after CRT could predict a confirmed complete response and favorable survival. Conclusions: This study showed that CRT improved the immunological characteristics of unresectable locally advanced ESCC and identified the density of PD-1+CD8+ T cells as a predictive factor for prognosis. This finding supports the rationale for the necessity of subsequent PD-1 inhibitor treatment. [ABSTRACT FROM AUTHOR]

Pyrolytic synergistic interactions, in which the production of pyrolyzates is enhanced or inhibited, commonly occur during the co-pyrolysis of different polymeric materials, such as plastics and biomass. Although these interactions can increase the yield of desired pyrolysis products under controlled degradation conditions, the desired compounds must be separated from complex pyrolyzates and further purified. To balance these dual effects, this study was aimed at examining pyrolytic synergistic interactions during slow heating co-pyrolysis of biodegradable plastics including polylactic acid (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyhexaoate) (PHBH) and petroleum-based plastics including high-density polyethylene (HDPE), polypropylene (PP), and polystyrene (PS). Comprehensive investigations based on thermogravimetric analysis, pyrolysis–gas chromatography/mass spectrometry, and evolved gas analysis-mass spectrometry revealed that PLA and PHBH decompose at lower temperatures (273–378 °C) than HDPE, PP, and PS (386–499 °C), with each polymer undergoing independent decomposition without any pyrolytic interactions. Thus, the independent pyrolysis of biodegradable plastics, such as PLA and PHBH, with common plastics, such as HDPE, PP, and PS, can theoretically be realized through temperature control, enabling the selective recovery of their pyrolyzates in different temperature ranges. Thus, pyrolytic approaches can facilitate the treatment of mixed biodegradable and common plastics. [ABSTRACT FROM AUTHOR]

• Latest trends and challenges in PVC and copper recovery technologies from thin cables. • Current technologies prioritize copper recovery, PVC recovery is low-priority. • Physical treatments alone cannot achieve high-purity PVC recovery from thin cables. • Combined chemical and physical treatments enable high-purity PVC and copper recovery. • Next-generation solutions for proper management of thin end-of-life cables. This review investigates the latest trends in separation technologies regarding hard-to-recycle thin cables, specifically in the form of end-of-life wire harnesses (WHs). The cables in WHs mainly contain copper (Cu) and poly(vinyl chloride) (PVC), which is commonly used to insulate and sheath cables. This review reveals that most separation technologies prioritize the recovery of Cu and overlook that of PVC. The recovery of high-purity PVC is very important because of its incompatibility with other plastics or Cu during recycling treatments. Through this investigation, we confirm that physical treatments, such as stripping and chopping, are insufficient to recover high-purity PVC from thin cables. Instead, a combination of chemical (e.g., swelling of PVC insulation or sheathing of cables under a suitable solvent) and physical (e.g., ball or rod milling and mechanical agitation of swollen cables) treatments can be used to achieve the recovery of high-purity PVC and Cu both for recycling. We believe that recovering metals and plastics from end-of-life cables is vital for sustainable waste management, offering several environmental and economic benefits. [ABSTRACT FROM AUTHOR]

Cancer cells employ glycolysis for their survival and growth (the "Warburg effect"). Consequently, surrounding cells including immune cells in the tumor microenvironment (TME) are exposed to hypoglycemic, hypoxic, and low pH circumstances. Since effector T cells depend on the glycolysis for their survival and functions, the metabolically harsh TME established by cancer cells is unfavorable, resulting in the impairment of effective antitumor immune responses. By contrast, immunosuppressive cells such as regulatory T (Treg) cells can infiltrate, proliferate, survive, and exert immunosuppressive functions in the metabolically harsh TME, indicating the different metabolic dependance between effector T cells and Treg cells. Indeed, some metabolites that are harmful for effector T cells can be utilized by Treg cells; lactic acid, a harmful metabolite for effector T cells, is available for Treg cell proliferation and functions. Deficiency of amino acids such as tryptophan and glutamine in the TME impairs effector T cell activation but increases Treg cell populations. Furthermore, hypoxia upregulates fatty acid oxidation via hypoxia-inducible factor 1α (HIF-1α) and promotes Treg cell migration. Adenosine is induced by the ectonucleotidases CD39 and CD73, which are strongly induced by HIF-1α, and reportedly accelerates Treg cell development by upregulating Foxp3 expression in T cells via A2AR-mediated signals. Therefore, this review focuses on the current views of the unique metabolism of Treg cells dictated by cancer cells. In addition, potential cancer combination therapies with immunotherapy and metabolic molecularly targeted reagents that modulate Treg cells in the TME are discussed to develop "immune metabolism-based precision medicine". [ABSTRACT FROM AUTHOR]

Studies have established immunochemotherapy as the first-line treatment for advanced esophageal cancer. Chen et al. and Carrol et al. performed exploratory analysis of the JUPITER-06 and LUD2015-005 trials, respectively and identified biomarkers to predict therapy response based on immunogenomic analysis. These findings may optimize precise patient stratification in advanced esophageal cancer. [ABSTRACT FROM AUTHOR]

With the ever-growing concern regarding plastic waste and its impact on the environment, understanding the degradation pathways of polyimide (PI)-based plastics becomes increasingly crucial for developing sustainable waste management strategies. This study investigated the thermo-oxidative degradation of PI-based plastics, including PI, polyamide-imide (PAI), and polyetherimide (PEI). We used techniques including thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy, an in situ heated electron spin resonance spectrometer, and a customized pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) system. The TGA results revealed that the onset degradation temperature of PI-based plastics exceeded 460 °C. The degradation of PI was promoted under air, while the degradation of PAI was delayed. For PEI, the degradation under air coincided with its initial decomposition under N 2 , followed by the oxidation of the residual solid. Changes in the chemical structures were revealed during the characterization of the samples treated above 400 °C. The residual char, obtained in high yield, notably contained N-rich functional groups. Real-time analysis using Py-GC/MS revealed that the pyrolysis of the plastics produced gases such as NH 3 , HCN, H 2 O, CO, and CO 2 , with NH 3 and HCN being converted into NO x under an atmosphere of air. The pyrolysis of PI and PAI generated N-containing compounds, including aromatic amines, nitriles, and phthalimides. In contrast, the pyrolysis of PEI produced various phenolic compounds owing to the presence of the aromatic ether groups. The newly formed p -benzoquinone, CO 2 , H 2 O, and NO x were identified under air. This study provides comprehensive insights into the unique thermal and oxidative stabilities of PI-based plastics and holds the potential for recovering high-value N-containing materials from waste PI-based plastics. • Thermo-oxidative degradation of polyimide-based plastics was investigated. • Changes in chemical structures occurred over 400 °C and improved in air. • Residual char obtained in high yield contained N-rich functional groups. • Customized Py-GC/MS revealed distinct degradation steps under various atmospheres. [ABSTRACT FROM AUTHOR]

[Display omitted] • The co-pyrolysis of cellulose, xylan, and milled wood lignin is studied. • The interactions of the components are identified via hierarchical clustering. • The types of the response surfaces reflect the pyrolytic interactions. • This study predicts the pyrolyzate distribution based on the biomass composition. • This method is also applicable in analyzing other operating conditions. The pyrolysis behavior of lignocellulosic biomass is complex owing to the different combinations of the three main components, and the diversity of the pyrolyzate distribution renders the identification of the pyrolytic synergy of lignocellulosic components challenging. Herein, the co-pyrolysis of cellulose, xylan (a representative example of hemicellulose), and milled wood lignin (MWL) was investigated using hierarchical clustering analysis (HCA) combined with a simplex lattice mixture design. HCA revealed that MWL enhanced cellulose-derived levoglucosan (LG) production, with a 2.1-fold higher theoretical yield, owing to the inhibition of LG repolymerization. The cellulose-xylan-MWL interactions resulted in yields of 1,4:3,6-dianhydro-α-d-glucopyranose, glycolaldehyde, and furfural that were > 1.2-fold higher than those theoretically calculated. The ternary interactions also increased the yields of phenol, p -cresol, 3,5-dimethylphenol, 3-methoxy-1,2-benzenediol, and methylphenol, which is attributed to H-donation by cellulose and xylan pyrolyzates. The yield prediction models of the pyrolyzates were established based on the HCA-identified interactions. The cubic model fitted the yields of gas, LG, glycolaldehyde, furfural, and char that were influenced by ternary interactions. The quadratic model predicted the yields of CO, CO 2 , CH 4 , and C 2 H 6 , which were primarily influenced by binary interactions. This study elucidates the complex pyrolytic interactions between lignocellulosic components and predicts the pyrolyzate distribution based on the biomass composition. This is beneficial for the targeted recovery of desirable chemicals from various biomass resources. [ABSTRACT FROM AUTHOR]

The thermal treatment of plastic solid wastes has been widely considered as an environmentally friendly process for converting the inherent polymeric units into fuel or chemicals. In the proposed study, the co-pyrolysis of printed circuit boards (PCB) and waste tires (WT) was performed using thermogravimetry (TG) and pyrolysis-gas chromatography/mass spectrometry. PCB and WT were blended in various ratios to investigate synergistic effects on the product characteristics and heteroatom migration. The TG results show that the PCB/WT blends shifted the PCB decomposition peak from 325 to 357 °C but accelerated the WT decomposition at the later stages. The pyrolysis products of PCB consisted of phenolic and brominated compounds, whereas olefins were the predominant products during WT pyrolysis. The addition of WT significantly improved the formation of small phenolics at the expense of bisphenol A, leading to a 40–51% and 24–92% increase in the production of phenol and p-isopropylphenol, respectively. Meanwhile, the production of major compounds from WT pyrolysis, including isoprene and D -limonene, was significantly reduced, indicating that the H-donor sources in WT could be favorable for further decomposing PCB, while improving the phenol production. Furthermore, the co-pyrolysis of PCB and WT resulted in a 26–47% and 50–59% decrease in tetrabromobisphenol A and benzothiazole production, respectively, indicating the excellent removal of toxic compounds. Characterization of the pyrolytic char indicated that co-pyrolysis was beneficial for transforming sulfur compounds into sulfates, whereas the addition of 75% WT was able to capture 12 times the amount of bromine in the char. The results suggest that the co-pyrolysis of PCB and WT can be a potential treatment to increase the production of phenol in oils with a low bromine content. [ABSTRACT FROM AUTHOR]

[Display omitted] • A high-pressure tandem μ-reactor-gas chromatography/mass spectrometry was applied. • Effects of atmosphere, temperature, catalyst and pressure were determined. • High temperature and H 2 pressure favored the production of valuable aromatics. • H 2 promoted the hydrocracking of the labile fraction of char at high temperatures. • Hydropyrolysis and upgrading parameters for lignin conversion was optimized. Hydropyrolysis is a promising route for converting biomass into valuable chemicals. A high-pressure tandem μ-reactor – gas chromatography/mass spectrometry was used to study the pyrolysis of lignin and probe the effects of reaction atmosphere (H 2 vs He), temperature, catalyst (HZSM-5) presence/absence, and pressure on product yields and distributions. Hydropyrolysis favored the demethoxylation and demethylation of guaiacyl-derived intermediates, generating catechol- and phenol-type compounds. The yields of guaiacyl- and catechol-type compounds decreased with increasing temperature and H 2 pressure. The products formed at the highest examined temperature (700 °C) and H 2 pressure (3.0 MPa) were dominated by phenol-type compounds, monoaromatic hydrocarbons (MAHs), and polycyclic aromatic hydrocarbons (PAHs). The substantial decrease in char yield with increasing H 2 pressure at 700 °C indicated that active hydrogen radicals enhanced the cracking of lignin macromolecules and suppressed the condensation reactions to form char at high temperatures. HZSM-5 exhibited considerable hydrocracking activity for converting lignin pyrolysis vapor into aromatics, with an increase in H 2 pressure further improving the formation of benzene, toluene, and xylenes (BTX) at the expense of phenolics. However, high catalytic upgrading temperatures favored the coupling reactions in the hydrocarbon pool, promoting the formation of PAHs. Evolved gas analysis showed that lignin hydropyrolysis involved two stages (at 250–500 and 500–800 °C), suggesting that the labile fraction of the nascent char underwent further hydrocracking at high pressure and temperature. The high production of BTX and naphthalenes through catalytic hydropyrolysis of lignin provides a promising route for the valorization of lignin-rich resources. [ABSTRACT FROM AUTHOR]

• Co-pyrolysis of PVC with cellulose, xylan, and milled wood lignin was performed. • Our approach improved compound separation ability and detected numerous pyrolyzates. • Hierarchical cluster analysis was used to rapidly screen for pyrolytic interactions. • Hydrogen chloride from PVC catalyzed dehydration of levoglucosan from cellulose. • Hydrogen chloride enhanced conversion of methoxyphenols into phenolic compounds. Co-pyrolysis of plastic/lignocellulosic biomass mixtures produces an extremely complex assortment of pyrolyzates. In the present work, co-pyrolysis of PVC with cellulose or xylan or milled wood lignin was conducted by employing pyrolysis–two-dimensional gas chromatography–time-of-flight mass spectrometry (Py-GC × GC-TOFMS) with the aim of achieving high throughput and comprehensive analysis of the complex pyrolyzates. Then, hierarchical cluster analysis (HCA), which is an algorithm that groups similar objects into groups called clusters, was applied to accomplish rapid screening for compounds influenced by pyrolytic interactions. This combined approach improved compound separation and identifiability and allowed the subsequent easy identification of new compounds and compounds increased or decreased by pyrolytic interactions during co-pyrolysis. The change in distribution during co-pyrolysis clearly suggests the occurrence of HCl-catalyzed dehydration of anhydrosugars and conversion of methoxyphenols into phenolic compounds. Thus, this study reveals the effectiveness of the approach combining Py-GC × GC-TOFMS with HCA, which promises to contribute to the acceleration of research on pyrolytic interactions. The understanding of pyrolytic interactions gained thereby will be crucial for maximizing the yield and quality of desired chemicals and fuels from plastic/lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) (PVC) swelling coupled with ball milling was employed for the simultaneous recovery of high-purity Cu and PVC from waste wire harness under ambient conditions. The experimentally determined performances of 15 organic solvents for PVC swelling and phthalate plasticiser extraction were compared with those predicted considering Hansen solubility parameters. As a result, n-butyl acetate and acetone were identified as the two best solvents for adequate PVC swelling without PVC dissolution and almost complete plasticiser extraction within 60 min. The swelling was concluded to contribute to the control of phthalate plasticisers, the use of which in wire harness has recently been limited by the Restriction of Hazardous Substances (RoHS) directive. Cables swollen with n-butyl acetate or acetone were subjected to dry ball milling for ~ 60 min to completely separate PVC and Cu and achieve the quantitative recovery of these components from 20-cm-long cables. Thus, this work unveils the high potential of recycling the otherwise non-recyclable long and non-uniform waste wire harness cables and is expected to impact the related (e.g., automotive, electrical, and electronics) industries, contributing to the establishment of a more sustainable society. [ABSTRACT FROM AUTHOR]

• High-purity Cu and PVC were simultaneously recycled from thin electric cables. • PVC swelling and centrifugal action were combined to separate PVC and Cu. • PVC, Cu, and plasticizers were separated in a single organic solvent. • Plasticizer-imbedded PVC and Cu were recovered in ester/H 2 O mixtures. Waste electric cables from end-of-life vehicles and electronic and electrical equipment present a significant problem in terms of environmental protection and resource recycling. Herein we detail a novel recycling method for thin waste electric cables, by combining polyvinyl chloride (PVC) swelling and centrifugal separation to simultaneously recover PVC and high-purity copper. PVC coverings were swollen in an organic solvent at ambient temperatures, which creates a gap between the covering and the copper wire and facilitates centrifugal separation. Electric cables (12 g) were 100% separated, and more than 95% of the plasticizer was extracted by stirring in 100-mL acetone or ethyl acetate that facilitated the separate recovery of copper, the PVC covering, and the plasticizer. In contrast, >97% separation, with <10% extraction of the plasticizer, was achieved with a mixture of 10 mL butyl acetate and 90 mL water. High-purity copper and PVC with controlled plasticizer content were recovered, which is highly advantageous for recycling both copper and PVC. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Polyurethanes (PUs) were converted into H 2 -rich syngas. • Toxic HCN was highly removed simultaneous with H 2 -rich syngas production. • Ni/Mg/Al catalysts simultaneously achieved H 2 -rich syngas recovery and HCN removal. • Synergy between Ni, Mg, and Al in the catalysts show excellent performance. • Variety of PUs (flexible and rigid forms and elastomers) were treated by this process. Abstract Polyurethanes (PUs) such as flexible (cushioning material and sponge) and rigid (different insulators) forms and elastomers (flexible tube and smartphone case) were thermally decomposed at 500 °C. The useless decomposition products were converted into H 2 -rich syngas and the toxic HCN in it was removed by Ni/Mg/Al catalysts at 800 °C under 50 vol% steam/He flow. The resultant total gas production was 1411–1623 mL/g (H 2 : 794–967 mL/g), which was almost 30 times larger than that obtained from simple pyrolysis of PUs where no H 2 was produced. Meanwhile, there was a drastic reduction of HCN concentration in the product gas from a maximum at 2.8 to 0.2–0.6 vol%. The excellent performance on the removal of HCN and the enhanced H 2 -rich syngas production is due to the synergy between Ni, Mg, and Al in the catalysts. This approach has great promise for treating a variety of PU wastes that cannot be recycled effectively otherwise. [ABSTRACT FROM AUTHOR]

The pyrolysis of bisphenol A (BPA), an essential process ingredient used in industry and many everyday life products, helps produce low-industrial-demand chemicals such as isopropenyl- and isopropyl-phenols (IPP and iPrP). In this study, tandem micro-reactor gas chromatography/mass spectrometry combined with an H2 generator (H2-TR-GC/MS) was employed for the first time to investigate the selective recovery of phenol via simultaneous hydrogenation/dealkylation of IPP and iPrP. After investigating the iPrP dealkylation performances of several zeolites, we obtained full iPrP conversion with over 99% phenol selectivity using the Y-zeolite at 350 °C. In contrast, when applied to IPP, the zeolite acid centres caused IPP polymerisation and subsequent IPP-polymer cracking, resulting in many byproducts and reduced phenol selectivity. This challenge was overcome by the addition of 0.3 wt% Ni on the Y-zeolite (0.3Ni/Y), which enabled the hydrogenation of IPP into iPrP and subsequent dealkylation into phenol (full IPP conversion with 92% phenol selectivity). Moreover, the catalyst deactivation and product distribution over repetitive catalytic use were successfully monitored using the H2-TR-GC/MS system. We believe that the findings presented herein could allow the recovery of phenol-rich products from polymeric waste with BPA macro skeleton. [ABSTRACT FROM AUTHOR]

Nitrate-intercalated Mg Al layered double hydroxide (LDH) was successfully delaminated in water by a facile and effective method upon reflux at 120 °C for 24 h followed by sonication at 40 °C for 5 h. This process is environmentally friendly since water is the only solvent used. The delaminated nanosheets were characterized by microscopic, spectroscopic, and particle size analyses. The delamination process successfully produced octahedron-shaped single-layer nanosheets 50–150 nm in size. X-ray photoelectron spectroscopy (XPS) data confirmed that the surface elements and their chemical status are consistent with the basic layer of Mg Al LDH. The delaminated nanosheets displayed higher adsorption capacity for removing heavy metals from waste water than the original powdered LDH. After treating the waste water, a sharp and intense peak in the X-ray powder diffraction (XRD) pattern of the precipitate confirms the restacking of the LDH nanosheets. [ABSTRACT FROM AUTHOR]

This article describes the production and properties of gases produced by the pyrolyses of poly(ethylene terephthalate) (PET), polypropylene (PP), polyethylene (PE), poly(vinyl chloride) (PVC), and polystyrene (PS), and three of their mixtures at process temperatures of 500, 700, and 900 °C. The overall aim was to characterize all 24 gases in terms of their production and physical properties, and compare the data obtained to those of traditional fuels, namely natural gas (NG) and propane. In addition to experimental and analytical approaches for determining quantities and compositions of the pyrolysis products, various mathematical methods and their combinations were also used to determine product properties. The highest conversion of material into gas occurred during the pyrolysis of PP at 900 °C (66.88 wt% conversion into gaseous products). The pyrolyses of PE and PP at 500 °C were found to generate pyrolysis gases with the highest energy, with gross calorific values of 86.58 and 81.09 MJ m −3 N , respectively. The highest chemical energy yield was obtained by the pyrolysis of PP at 900 °C. Gases produced from PVC had a high thermal conductivity of about 104.83 mW m −1  K −1 . The gas generated from PP at 500 °C exhibited a high specific heat of 2.94 kJ m −3 N  K −1 , and that obtained from PS at 500 °C had a very low kinematic viscosity (5.28 10 −6  m 2  s −1 ) and thermal diffusivity (7.90 10 −6  m 2  s −1 ). Even though numerous reports have dealt with pyrolysis gases, there is still not sufficient information about the specific physical properties of these gases. This article attempts to fill this gap and induce scientific interest in this field. [ABSTRACT FROM AUTHOR]

The current energy industry relies heavily on fossil fuels. As reserves of fossil fuels are diminishing, the demands for alternative forms of energy are growing. Therefore, the search for alternative fuels is crucial. This article discusses pyrolysis gases generated from major plastics as possible future successors to fossil fuels. The novelty of this study lies in the comprehensive discussion of the fuel characteristics of different pyrolysis gases that are so far unpublished. The article builds on Part I, which predominantly focused on the production and physical properties of pyrolysis gases from plastics. Various properties are determined by combining experimental and mathematical methods. An interesting aspect of the gases produced from poly(ethylene terephthalate) (PET) is their high upper flammability limits, which are 61.46% on average. Gases from poly(vinyl chloride) (PVC) are characterized by very high laminar burning velocities, with an average value of 178.62 cm s −1 , which is about five times higher than that of natural gas (NG). Gases produced from PVC at 500 and 700 °C have autoignition temperatures almost identical to that of NG. Furthermore, the results presented in this article show that, according to standards proposed by the California Air Resources Board and the Gas Research Institute, none of the pyrolysis gases are suitable fuels for gas engines, because the methane number of no gas meets the minimum value of 65 required in the EU and USA. This article discusses results valuable for determining the potential suitability of pyrolysis gases for use in power-engineering facilities, including combustion engines, and includes information on further research prospects. [ABSTRACT FROM AUTHOR]

The treatment of cesium-contaminated wastewater has become one of the biggest issues. The selective Cs + removal from wastewater containing competitive alkali metal ions such as Na + is desired to reduce the volume of sludge. Therefore, the present work focused on water-soluble calix[4]arene-bis-crown-6 (W-BisC6) to selectively capture Cs + . For characterization of the complex, UV–vis spectroscopy is commonly used, however, due to the limited availability of information it can be hard to quickly identify the specific structures of some complexes. In this work, the electrospray ionization time of flight spectrometry (ESI-TOF-MS) is successfully utilized to identify the number and type of cations in W-BisC6-cation complexes. ESI-TOF-MS accurately recognized 4 types of complex (W-BisC6–Na + , W-BisC6–Cs + , W-BisC6–2Na + , W-BisC6–Na + –Cs + ), and the experimental and simulated results were almost perfectly matched. It also revealed the difficulty of W-BisC6–2Cs + complex formation under the present conditions. Thus, this technique is significantly helpful for rapid identification of the specific structures of complexes during Cs + -contaminated wastewater treatment. [ABSTRACT FROM AUTHOR]

During the tandem pyrolysis of poly(ethylene terephthalate) (PET) and catalytic conversion of the PET pyrolysates over calcium oxide (PET/CaO process), the relationship between catalyst deterioration and the aromatic hydrocarbon selectivity was elucidated. Using a tandem micro (µ)-reactor-gas chromatography/mass spectrometry (TR-GC/MS) system, PET was pyrolyzed at 450 °C in the 1st µ-reactor and the PET pyrolysates were refined over one of two CaO catalysts with different basicities at 700 °C in the 2nd µ-reactor. Strongly basic CaO enhanced benzene production via decarboxylation, resulting in 83.6% selectivity for aromatic hydrocarbon products. This selectivity decreased with repeated runs over the strongly basic CaO, while oxygen-containing compounds such as benzophenone and benzoic acid increased. The surface morphology changes observed by scanning electron microscopy indicated that CaO was thoroughly sintered with repeated use, which reduced its basicity. The less-basic CaO effected diminished carboxyl-unit surface adsorption and suffered deteriorated deoxygenation ability. Thus, this study clearly demonstrates that CaO deterioration (by sintering during repeated PET/CaO processing) and CaO basicity strongly influence reaction selectivity. [ABSTRACT FROM AUTHOR]

A study of the morphology changes in polyurethane elastomers (PUEs) containing different hard- and soft-segment ratios during ramped-heating pyrolysis revealed that selectivity of urethane bond cleavage is controlled by only the segment composition. Several PUEs were synthesized using 4,4′-diphenylmethane diisocyanate, 1,4-butanediol, and poly(oxytetramethylene glycol) (PTMG) to examine the influence of segment composition on pyrolysis characteristics by pyrolysis–gas chromatography/mass spectrometry, evolved gas analysis–mass spectrometry, and isoconversional kinetic studies. Soft-segment-rich PUEs tended to undergo urethane bond cleavage via a 4-membered-ring transition state, while the linkages in other compositions were selectively cleaved via a 6-membered-ring transition state. The reaction selectivity can be explained by the different conformations of the urethane bonds: in the hard-segment domains by H-bonds between urethane unit N H and C O groups, and in soft-segment-rich environments by H-bonds between urethane N H groups and PTMG O linkages. The mechanism of PTMG pyrolysis was the same for all PUEs. [ABSTRACT FROM AUTHOR]

Pyrolysis is an important method for breaking down organic waste to obtain useful low molecular weight compounds. To investigate the pyrolysis behavior of bisphenol A (BPA) and BPA pyrolysates at low pyrolytic temperatures, BPA and p -isopropenyl phenol (IPP) were pyrolyzed at 240–320 °C using a batch reactor. BPA decomposition was strongly enhanced at temperatures higher than 240 °C, and was almost complete after 30 min at 320 °C. Theoretically, pyrolysis of BPA gives phenol (PhOH) and IPP in a 1:1 molar ratio, corresponding to yields of 41 wt% PhOH and 59 wt% IPP. However, an unexpectedly low IPP yield (∼10 wt%) was obtained experientially, with a simultaneous increase in the yields of high molecular weight compounds. Compounds resulting from IPP polymerization were detected using electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), suggesting that IPP was rapidly polymerized into high molecular weight compounds via radical propagation. On the other hand, a maximum PhOH yield of 62 wt% was obtained after 30 min at 320 °C, which is higher than the theoretical yield. As direct dealkylation of IPP is difficult, the excess PhOH is likely derived from thermal decomposition of the IPP polymerization products. Thus, the present work revealed the high reactivity of IPP for polymerization at pyrolytic temperatures, which facilitates increased recovery of PhOH from BPA. [ABSTRACT FROM AUTHOR]

The recycling of N -containing plastics by pyrolysis or steam-reforming is typically complicated by the generation of toxic HCN. In this study, polyimide, as an example of an N -containing plastic, was gasified and the product gas was reformed over various Ni/Mg/Al catalysts. Effects of catalyst properties, steam, and temperature on the HCN removal and H 2 -rich syngas production were investigated. More than 99% HCN removal (compared with pyrolytic conditions) and ∼3000 mL g −1 of H 2 -rich syngas with a H 2 /CO ratio of 10.4 were simultaneously achieved at 800 °C in the presence of a reduced-Ni 1.0 Mg 3.6 Al 4.8 catalyst, then HCN was mainly converted into N 2 . On the other hand, non-reduced same catalyst enhanced hydrolysis of HCN into NH 3 with more than 98% HCN removal at 800 °C, which is also a beneficial finding to recover useful NH 3 from HCN, directly. Therefore, the present work achieved that the improvement of the H 2 -rich syngas yield and quality, and conversion of toxic HCN into non-toxic N 2 or useful NH 3 using the same catalyst, simultaneously. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-pyrolysis of xylan and polyethylene was investigated at 500–700 °C. • Hierarchical clustering analysis (HCA) comprehensively evaluated pyrolytic synergies. • Response surface methodology (RSM) established the prediction models of pyrolyzates. • HCA complemented RSM deficiencies in identifying synergies of low-yield products. • Pyrolytic synergies improved the production of heavy gas oil and C ≥26 hydrocarbons. The distributions of biomass and plastic co-pyrolysis products are complicated by abundant component combinations, pyrolysis conditions, and synergies. Herein, the hierarchical clustering analysis (HCA) and response surface methodology (RSM) were used to rapidly determine synergies and predict product yields of xylan and polyethylene (PE) co-pyrolysis at 500–700 °C. The results showed that co-pyrolysis promoted liquid production and suppressed solid and char formation. Pyrolytic interactions improved the decomposition of the PE-derived wax, resulting in 1.5–1.9- and 1.7–2.1-fold higher yields of heavy gas oil and C ≥26 hydrocarbons compared to the theoretical values. HCA classified pyrolyzates with similar synergy into the same cluster, which reflected the suppressed carbonyl compound production, enhanced furfural and phenols yields at 700 °C, and greater C 17 –C 30 hydrocarbon production. The quadratic model of RSM predicted the yields of gas, CO, C 3 H n , C 4 H n , liquid, ethanol, acetaldehyde, hydrocarbon oil, gasoline, solid, and char influenced by synergies. Owing to complex interactions, the cubic model fitted the CH 4 and C 2 H 4 yields. The linear model described the CO 2 yield without synergy. This work illustrates the utility of combining RSM and HCA to predict product distributions of various waste co-treatment processes. [ABSTRACT FROM AUTHOR]

To investigate the interactions between beech wood (BW) and polyethylene (PE) during co-pyrolysis, they were pyrolyzed both individually and as their mixtures from ambient temperature to 650 °C at a heating rate of 10 °C min −1 using a thermogravimetric analyzer and a tube reactor. In the presence of PE, the production of levoglucosan (LG) and methoxyphenols with unsaturated alkyl side chains from BW was enhanced, resulting in maximum 1.65 and 1.55 times higher yields comparing with their expected yields from BW:PE (w:w) = 40:60 mixture, respectively. It was due to the stabilization of the radical species of those by H-abstraction from the PE pyrolysates in the vapor phase. According to this, CO, CO 2 , C 2 -C 3 compounds, and 5-membered ring compounds, which are LG decomposition products, showed 0.86, 0.85, 0.58, and 0.68 times smaller yields comparing with their expected yields. Methoxyphenols with saturated alkyl side chains, phenols, and catechols, also showed 0.77, 0.66, and 0.87 times smaller yields because they are mainly derived from methoxyphenols with unsaturated alkyl side chains. On the other hand, it was suggested that hydrogen radicals produced during the polyaromatization of BW stabilized PE radical species, resulting in products from PE with higher carbon numbers. Thus, the present work reveals that the interactions between BW and PE mainly involve H-exchange to stabilize radical species. These findings increase our understanding of the operative mechanism in the co-pyrolysis of lignocellulosic biomass and synthetic polymers, which will be useful in future for achieving pyrolysis reaction control and recovering desirable products from difficult-to-separate initial mixtures. [ABSTRACT FROM AUTHOR]

The global increase in natural gas (NG) consumption and its steady decline in availability have spurred the search for new or alternative energy sources, such as pyrolysis gases. This article examines whether it is possible to burn pyrolysis gases from common plastic wastes in conventional burners without any adjustment to burner design. To determine the interchangeability of individual gases, several multi-index methods applicable to combustion devices in Europe, the USA, and the UK were used. This report is a continuation of a previous article (Part I) discussing the results of graphical methods for determining interchangeability. Similar to Part I, the results here imply that poly(vinyl chloride) (PVC) gases produced at a minimum of 700 °C have the highest replacement potential, and gases produced by polystyrene (PS) pyrolysis at 900 °C also conform with replacement requirements. For plastics mixtures, gases generated by pyrolysis at a minimum of 700 °C would be suitable alternatives to NG. These findings may contribute to plastic waste reduction as well as the discussion of reducing NG consumption. There is significant potential for follow-up research in this area, because the replacement of conventional fuels with gases obtained from wastes has not yet been sufficiently explored. [ABSTRACT FROM AUTHOR]

The development of effective recycling methods for plastic wastes is critical in terms of resource security and environmental conservation. In this work, we focused on the gaseous pyrolysis products of plastic wastes as alternatives to natural gas (NG) and propane. The pyrolysis of polyethylene (PE), polypropylene (PP), polystyrene (PS), poly(vinyl chloride) (PVC), poly(ethylene terephthalate) (PET), and their mixtures was carried out under isothermal conditions at 500, 700, and 900 °C. The potential for replacing NG and propane with the pyrolysis gases was assessed by graphical interchangeability methods for the first time. The pyrolysis gas compositions obtained from the mixed plastics and HCl-scrubbed gas from the PVC were deemed suitable NG alternatives in Europe and the USA. In addition, PE and PP pyrolysis gases showed the potential for replacing propane in the USA, whereas gases from PET showed the least interchangeability. Thus, the graphical interchangeability methods are promising for evaluating the potential of plastic waste pyrolysis gases as alternatives to NG. [ABSTRACT FROM AUTHOR]

Correction for 'Enhanced production of phenol and debromination by co-pyrolysis of the non-metallic fraction of printed circuit boards and waste tires' by Chuan Ma et al., Green Chem., 2021, 23, 6392–6404, DOI: 10.1039/D1GC01176F. [ABSTRACT FROM AUTHOR]

The use of sulfur-based plastics has led to the accumulation of end-of-life sulfur-based plastic waste that should ideally be recycled. In this study, several technologies were applied to investigate the thermal-oxidative degradation property of sulfur-based plastics (polyphenylene sulfide (PPS), polyether sulfone (PES), and polysulfone (PSU)). Thermogravimetric analysis (TGA) revealed that these plastics undergo major decomposition at 450–650 °C under N 2 , whereas two-stage weight loss at 450–690 °C was observed in air. X-ray photoelectron spectroscopy (XPS) and in-situ radical monitoring by heated electron spin resonance (heated-ESR) spectroscopy revealed that the samples had altered their chemical structures, and that radicals are involved in samples treated at low temperature (≤ 400 °C). The thermo-oxidative products were analyzed by customized pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). PPS pyrolysis mainly produced sulfur-containing aromatic compounds, with H 2 O, CO 2 , and SO 2 released during two-stage degradation in air, which suggests that pyrolysis and oxidation occur simultaneously during the first stage. PES pyrolysis generated various oxygen-containing products, whereas the oxidation of PES resulted in a great number of furans and dioxins at the expense of phenolics. Extensive evolution of SO 2 was initially observed, irrespective of the degradation atmosphere. PSU pyrolysis produced various aromatics, phenolics, and esters, with SO 2 formed as the major sulfur-containing compound, which was released at a lower temperature (∼50 °C) in air compared to N 2 , confirming that PSU is less thermally stable than PPS and PES in air, as observed by TGA. The thermo-oxidative degradation behavior of sulfur-based plastics was comprehensively characterized by combining conventional techniques (TGA and XPS) with advanced analytical technologies (heated-ESR and customized Py-GC/MS). • The thermo-oxidative degradation of sulfur-based plastics was investigated. • Heated-ESR spectroscopy revealed excited radicals at low temperature. • Thermo-oxidative products were analyzed online using customized Py-GC/MS. • The release of products formed in different atmospheres was studied. [ABSTRACT FROM AUTHOR]

Kapton film, which is a typical aromatic polyimide (PI) film, exhibits excellent thermal stability and flexibility. Therefore, it is used widely for flexible printed circuit boards in combination with other resins and metals. However, this makes it difficult to recycle it. In this work, we focused on the steam pyrolysis technique, which is a method of depolymerizing condensation polymers without solvents, catalysts, or high pressure, as a way of overcoming this issue. The steam pyrolysis of Kapton film was carried out using a thermogravimetric (TG) analyzer equipped with a steam generator. In addition, the TG results were evaluated further using model fitting techniques. It was found that steam enhanced the hydrolysis of the imide ring, which occurred on the surface of the PI film. The hydrolysis selectivity was as high as 89% at 528 °C. However, steam did not significantly enhance the Kapton decomposition rate, owing to rapid carbonization, which took place because of the simultaneous occurrence of pyrolysis. Thus, the obtained results implied that high-yield monomer recovery can be achieved by lowering the temperature to prevent pyrolysis and by improving the steam contact efficiency to enhance hydrolysis within the material. [ABSTRACT FROM AUTHOR]

A Ni–Mg–Al–Ca catalyst was prepared by a co-precipitation method for hydrogen production from polymeric materials. The prepared catalyst was designed for both the steam cracking of hydrocarbons and for the in situ absorption of CO 2 via enhancement of the water–gas shift reaction. The influence of Ca content in the catalyst and catalyst calcination temperature in relation to the pyrolysis–gasification of a wood sawdust/polypropylene mixture was investigated. The highest hydrogen yield of 39.6 mol H 2 /g Ni with H 2 /CO ratio of 1.90 was obtained in the presence of the Ca containing catalyst of molar ratio Ni:Mg:Al:Ca = 1:1:1:4, calcined at 500 °C. In addition, thermogravimetric and morphology analyses of the reacted catalysts revealed that Ca introduction into the Ni–Mg–Al catalyst prevented the deposition of filamentous carbon on the catalyst surface. Furthermore, all metals were well dispersed in the catalyst after the pyrolysis–gasification process with 20–30 nm of NiO sized particles observed after the gasification without significant aggregation. [ABSTRACT FROM AUTHOR]

Individual and mixed plastics consisting of polyethylene (PE), polypropylene (PP), polystyrene (PS), and poly(ethylene terephthalate) (PET) were decomposed at 600 °C in the presence and absence of either calcium oxide (CaO) or calcium hydroxide (Ca(OH) 2 ) under a steam atmosphere. In the presence of CaO, steam cracking was enhanced, increasing gas and liquid yields and decreasing the wax content derived from PE and PP. The production of sublimating substances from PET was also reduced. However, the presence of CaO and steam had a negative influence on PS degradation, reducing the oil yield. In addition, synergistic effects were observed in plastic mixtures. PET enhanced gasification, PS and PET reduced wax production from PE and PP, and mixing all four plastics enhanced oil production in the presence of CaO and steam. Both CaO and Ca(OH) 2 enhanced the total gas and oil yield of mixed plastics, achieving a maximum oil yield of 52.2 wt% in the presence of steam. Furthermore, solids were almost completely decomposed at 700 °C, with only 0.2 wt% of residue remaining. [ABSTRACT FROM AUTHOR]

Fast co-pyrolysis has been suggested as a promising technique to solve the environmental issues and simultaneously recover value-added products from polymer wastes. However, to date, no studies have focused on fast co-pyrolysis of printed circuit boards (PCB) and waste tire (WT). Therefore, we comprehensively investigated the fast co-pyrolysis of PCB and WT using pyrolysis-gas chromatography/mass spectrometry. The results show that an increase in temperature during fast pyrolysis improved the interactions between the PCB and WT pyrolyzates, increasing the formation of aliphatic and aromatic compounds. The formation of p -cymene was greatly induced by the isomerization and dehydrogenation reactions of D -limonene. Co-pyrolysis reduced the formation of brominated phenols and benzothiazole from PCB and WT pyrolysis, respectively, whereas promoted the interactions between Br- and S/N-containing radicals, concentrating them into heavy compounds. Increasing the temperature enhanced the release of heteroatom compounds. The findings suggest that debromination of PCB achieved via dehydrogenation of WT pyrolysis provoked secondary reactions of olefins and interactions of heteroatom radicals. The major products were accurately predicted by different fitting models using response surface methodology, indicating the synergistic interactions during co-pyrolysis. The results were beneficial for optimizing the experimental parameters to obtain the maximum yield of desired products. [Display omitted] • Fast co-pyrolysis produced higher yields of BTEX and p -cymene. • Hydrogen donors from waste tire pyrolysis favored the debromination of PCB. • Br- and S/N-heteroatoms were concentrated into higher boiling point compounds. • The major products were accurately predicted using response surface methodology. • Possible pyrolytic interactions were proposed. [ABSTRACT FROM AUTHOR]

Owing to the low atmospheric concentration of CO 2 (400 ppm), direct air capture technologies require adsorbents that offer high CO 2 adsorption capacities at low CO 2 concentrations. In this study, we investigated the potential of CO 3 ·Mg–Al layered double hydroxides (LDHs; Mg/Al molar ratio = 2, 3, and 4) as CO 2 adsorbents. The CO 2 adsorption and desorption behavior was studied at various molar ratios, adsorption/desorption temperatures, and linear speeds. CO 2 adsorption by CO 3 ·Mg–Al LDH followed the Langmuir model, indicating that monolayer adsorption occurs. The maximum CO 2 adsorption quantity calculated using the Langmuir equation was 0.794 mmol/g for CO 3 ·Mg–Al LDH with a Mg/Al molar ratio of 3. In dry CO 2 adsorption experiments, a maximum CO 2 adsorption quantity of 0.319 mmol/g was recorded with a Mg/Al molar ratio of 3 and temperature of 60 °C. In dry CO 2 desorption experiments, the CO 2 concentration and desorption quantity reached maximum values at 300 °C and a linear speed of 0.250 m/min. Notably, the maximum CO 2 concentration was 6232 ppm, showing a 15.6-fold increase in comparison with the initial concentration of 400 ppm. Overall, our results demonstrate that CO 3 ·Mg–Al LDH has high potential as a CO 2 adsorbent. The study findings have significant implications for the development of new CO 2 adsorbents for the direct air capture and storage of CO 2. • We have developed new CO 2 adsorbents for the direct air capture and storage of CO 2. • Our results demonstrate that CO 3 ·Mg–Al LDH has high potential as a CO 2 adsorbent. • CO 2 adsorption followed the Langmuir model, indicating that monolayer adsorption occurs. [ABSTRACT FROM AUTHOR]

Abstract: The addition of plastics to the steam pyrolysis/gasification of wood sawdust with and without a Ni/Al2O3 catalyst was investigated in order to increase the production of hydrogen in the gaseous stream. To study the influence of the biomass/plastic ratio in the initial feedstock, 5, 10 and 20 wt.% of polypropylene was introduced with the wood in the pyrolysis reactor. To investigate the effect of plastic type, a blend of 80 wt.% of biomass and 20 wt.% of either polypropylene, high density polyethylene, polystyrene or a mixture of real world plastics was fed into the reactor. The results showed that a higher gas yield (56.9 wt.%) and a higher hydrogen concentration and production (36.1 vol.% and 10.98 mmol H2 g−1 sample, respectively) were obtained in the gaseous fraction when 20 wt.% of polypropylene was mixed with the biomass. This significant improvement in gas and hydrogen yield was attributed to synergetic effects between intermediate species generated via co-pyrolysis. The Ni/Al2O3 catalyst dramatically improved the gas yield as well as the hydrogen concentration and production due to the enhancement of water gas shift and steam reforming reactions. Very low amounts of coke (less than 1 wt.% in all cases) were formed on the catalyst during reaction, with the deposited carbonaceous material being of the filamentous type. The Ni/Al2O3 catalyst was shown to be effective for hydrogen production in the co-pyrolysis/gasification process of wood sawdust and plastics. [Copyright &y& Elsevier]

ABSTRACT: The possibility of simultaneous recovery of benzene and metals from the hydrolysis of poly(ethylene terephthalate) (PBT)-based materials such as X-ray films, magnetic tape, and prepaid cards under a steam atmosphere at a temperature of 450 °C was evaluated. The hydrolysis resulted in metal-containing carbonaceous residue and volatile terephthalic acid (TPA). The effects of metals and additives on the recovery process were also investigated. All metals were quantitatively recovered, and silver, maghemite (γ-Fe2O3), and anatase (TiO2) were recovered without any changes in their crystal structures or compositions. In a second step, TPA was decarboxylized in the presence of calcium oxide (CaO) at 700 °C, producing benzene with an average yield of 34% and purity of 76%. Maghemite (γ-Fe2O3) incorporated in magnetic tape and prepaid cards could decarboxylate TPA. Aluminum present in the prepaid cards produced hydrogen by the reaction with steam. However, the presence of metals had no adverse influence on the recovery of benzene-rich oil in the presence of CaO. Therefore, this method can be applied to PET-based materials containing inorganic substances, which cannot be recycled effectively otherwise. [ABSTRACT FROM AUTHOR]

The balance of programmed death-1 (PD-1)-expressing CD8+ T cells and regulatory T (Treg) cells in the tumor microenvironment (TME) determines the clinical efficacy of PD-1 blockade therapy through the competition of their reactivation. However, factors that determine this balance remain unknown. Here, we show that Treg cells gain higher PD-1 expression than effector T cells in highly glycolytic tumors, including MYC-amplified tumors and liver tumors. Under low-glucose environments via glucose consumption by tumor cells, Treg cells actively absorbed lactic acid (LA) through monocarboxylate transporter 1 (MCT1), promoting NFAT1 translocation into the nucleus, thereby enhancing the expression of PD-1, whereas PD-1 expression by effector T cells was dampened. PD-1 blockade invigorated the PD-1-expressing Treg cells, resulting in treatment failure. We propose that LA in the highly glycolytic TME is an active checkpoint for the function of Treg cells in the TME via upregulation of PD-1 expression. [Display omitted] • LA induces PD-1 expression by Treg cells in highly glycolytic tumors • LA absorbed through MCT1 is a metabolic checkpoint of immune responses • MYC -amplified or liver metastatic tumors augment PD-1+ Treg cells with abundant LA • MCT1 highly expressed by Treg cells provides therapeutic target for immunotherapy Kumagai et al. show that Treg cells uptake lactic acid in the highly glycolytic tumor microenvironment via MCT1 and robustly express PD-1, resulting in the impairment of PD-1 blockade therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cellulose and polyethylene with different mixing ratios were pyrolyzed at 500–700 °C. • The prediction potential of response surface methodology was investigated. • Detailed pyrolyzate distribution models were established beyond gas, oil, and char. • Quadratic, cubic, linear, and 2FI equations can accurately predict product yields. • The type of product distribution model reflected the synergistic effects. There are numerous combinations of biomass, plastic, and co-pyrolysis conditions. The presence of synergies, which make pyrolyzate distribution more complex, has been supported by research. In this study, the potential of response surface methodology (RSM) to predict the pyrolyzate yields affected by synergies during co-pyrolysis (500–700 °C) of cellulose and polyethylene was investigated, beyond gas, oil, and char yields. The results indicated that co-pyrolysis promoted liquid and C 5–28 hydrocarbon production with increasing temperature. The quadratic model could predict the total gas, CO, CO 2 , and liquid yields, including the synergy. The cubic model could predict the levoglucosan and C 5–28 hydrocarbon yields due to various synergies under different conditions. The linear model was suitable for the char yield distribution without interaction. Thus, this study reveals that RSM has a significant potential to predict pyrolyzate yields, enabling co-pyrolysis condition setting to maximize the desired product recovery with the fewest experiments. [ABSTRACT FROM AUTHOR]

• Ethylene vinyl acetate (EVA) samples were deteriorated by UV irradiation. • Ketone and lactone formation in the aged samples was identified by conventional FTIR. • Pyrolyzates of the aged samples reflected the chemical structure of the aged EVA. • Micro UV irradiator was combined with Py-GC/MS for in-situ evolved gas monitoring. • UV/Py-GC/MS allowed identification of volatile compounds during the UV irradiation. Ethylene vinyl acetate (EVA), commonly used to encapsulate photovoltaic (PV) modules, deteriorates on prolonged exposure to sunlight. In this work, fresh and deteriorated EVA samples prepared by UV irradiation (500 W m−2) over different periods (0–168 h) are characterized by conventional elemental analysis, microscopic observations, Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetry. To the best of our knowledge, this is the first work to employ pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and micro-UV irradiation combined Py-GC/MS (UV/Py-GC/MS) to investigate the deterioration behavior of EVA, using in-situ identification of gases liberated during UV irradiation, such as H 2 O, CO 2 , ketones, acetic acid, and lactones. In addition, the deterioration of the thermal stability on aging is confirmed using evolved gas analysis-mass spectrometry (EGA-MS). UV/Py-GC/MS revealed that acetaldehyde, acetone, acetic acid, γ -butyrolactone, succinic anhydride, and cyclobutanone are produced during UV irradiation. In addition, Py-GC/MS identified cyclopentanone, citraconic anhydride, γ -valerolactone, and cyclobutanone from the UV deteriorated EVA samples, which suggested the presence of ketone and lactone structures in the deteriorated EVA. This work establishes the combined usage of UV irradiation and Py-GC/MS as a promising method to investigate UV deterioration behavior in greater detail. These findings may contribute to a superior understanding of the breakdown of PV modules by the deterioration of EVA, and lead to the development of UV-resistant encapsulating materials. [Display omitted] [ABSTRACT FROM AUTHOR]

The removal of toxic anions from wastewater by layered double oxides (LDOs) is highly efficient and studies related to the synthesis of LDOs have been actively attempted. This paper reports the synthesis of a triatomic LDO consisting of Mg, Fe, and Al by a novel sol-gel synthesis process using organic chains (previously developed by our group). This adsorbent exhibited an excellent adsorption performance for the removal of arsenate anions with a maximum adsorption capacity calculated by the Langmuir equation of 304.6 mg/g and an absorbance density of 1.33 mg/m2. The Mg–Fe–Al LDO synthesized via the sol-gel method adsorbed arsenate anions better than an Mg–Al LDO prepared by the same method. Furthermore, a highly effective process for the desorption of arsenate from the adsorbent was investigated. The results revealed that the maximum arsenate anion desorption was achieved via an anion exchange with an NaHCO 3 solution. Namely, we have succeeded in synthesizing a triatomic LDO of Mg, Fe, and Al by the sol-gel method that we established, and the adsorbent has excellent arsenate anion adsorption performance. [Display omitted] • The synthesis of a triatomic LDO consisting Mg, Fe and Al by this sol-gel process. • 1.7 times increase in specific surface area compared to Mg–Al LDO (coprecipitation). • A maximum adsorption capacity and an absorbance density of Mg–Fe–Al LDO (sol-gel) are the highest compared to both Mg–Al LDO (coprecipitation) and Mg–Al LDO (sol-gel). • A highly effective process for desorption of arsenate anion has been established. [ABSTRACT FROM AUTHOR]

Polycarbonate (PC) is an engineering thermoplastic that is widely used in electrical and electronic equipment. This plastic often contains tetrabromobisphenol A (TBBA), the most common brominated flame retardant. Thermal degradation of the PC-TBBA leads to generation of numerous bromo-organic products in the pyrolytic oil, hindering its appropriate utilization, as well as corrosive hydrogen bromide gas. The purpose of this study was to experimentally investigate and compare the pyrolysis products of PC-TBBA and PC-TBBA + Cu 2 O at various temperatures, with an emphasis on the yield and distribution of brominated compounds. In pyrolysis of PC-TBBA + Cu 2 O, at the maximum degradation temperature (600 °C), as much as 86% of total Br was trapped in the residue, while 3% and 11% were distributed in the condensate and gas fractions, respectively. In contrast, the distribution of Br from non-catalytic pyrolysis of PC-TBBA (600 °C) was 0.5% residue, 40% condensate, and 60% gas. The results of this study revealed that in the presence of Cu 2 O, organo-bromine products were most likely involved in Ullman-type coupling reactions, leading to early cross-linking of the polymer network that efficiently hinders their vaporization. HBr in the gas fraction was suppressed due to effective fixation of bromine in residue in the form of CuBr. ga1 • Cu 2 O significantly alter the pyrolysis of bromine-containing PC polymer. • Cu 2 O mediates cross-coupling of bromo-organics at early stage of pyrolysis. • Cu 2 O significantly reduces vaporization of bromo-organic products and HBr gas. • Cu 2 O utilizes efficiently CO in reduction reactions, favoring CO 2 generation. [ABSTRACT FROM AUTHOR]

Only a small percentage of patients afflicted with gastric cancer (GC) respond to immune checkpoint blockade (ICB). To study the mechanisms underlying this resistance, we examined the immune landscape of GC. A subset of these tumors was characterized by high frequencies of regulatory T (Treg) cells and low numbers of effector T cells. Genomic analyses revealed that these tumors bore mutations in RHOA that are known to drive tumor progression. RHOA mutations in cancer cells activated the PI3K-AKT-mTOR signaling pathway, increasing production of free fatty acids that are more effectively consumed by Treg cells than effector T cells. RHOA mutant tumors were resistant to PD-1 blockade but responded to combination of PD-1 blockade with inhibitors of the PI3K pathway or therapies targeting Treg cells. We propose that the metabolic advantage conferred by RHOA mutations enables Treg cell accumulation within GC tumors, generating an immunosuppressive TME that underlies resistance to ICB. • RHOA Y42-mutated GC harbors abundant Treg cell and low CD8+ T cell infiltration in TME • RHOA Y42 mutations reduce CXCL10 and CXCL11 production via activated PI3K-AKT pathways • PI3K pathways activated by RHOA Y42 mutations provide a metabolic advantage for Treg cells • A PI3K inhibitor overcomes resistance to PD-1 blockade in RHOA Y42-mutated tumors Kumagai et al. find that a subset of gastric cancer (GC) tumors are characterized by high frequencies of regulatory T (Treg) cells and low numbers of effector T cells; these tumors bear mutations in RHOA. RHOA mutations activated the PI3K-AKT-mTOR pathway, increasing production of free fatty acids that are more effectively consumed by Treg cells than effector T cells. [ABSTRACT FROM AUTHOR]

• PU elastomers with different hard segment (HS) domain structures were prepared. • Fast and slow pyrolysis of the synthesized polyurethane elastomers were conducted. • There was no significant difference in type of pyrolysates between the samples. • HS selectively produced compounds with isocyanate end group at around 280–340 °C. • Pyrolysis of HS domain and HS in soft segment occurred at different temperatures. The pyrolysis behaviors of seven kinds of polyurethane elastomers (PUEs) with different ratios between the hard segment (HS) and soft segment (SS) were investigated for both fast pyrolysis (300, 350, 450, 850 °C) and slow pyrolysis at the heating rate of 10 °C min–1 by thermogravimetric analysis (TG), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), and evolved gas analysis-mass spectrometry (EGA-MS). These PUEs were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), 1,4-butane diol (BD), and poly(oxytetramethylene glycol) (PTMG). Atomic force microscopy measurements found that the HS domains were formed in PUEs containing HS, and these domains were aggregated at extremely high HS ratio. The main pyrolysate derived from HS was MDI under all conditions. In fast pyrolysis tests, the decomposition of SS proceeded sufficiently at 450 °C, and a lot of low molecular weight compounds were produced at 850 °C. In slow pyrolysis tests, three-step degradation was observed, and this degradation behavior was influenced by the HS domain and SS matrix structures. The first step is the HS pyrolysis inside the HS domain, then the HS surrounded by SS is pyrolyzed. Finally, the SS matrix is pyrolyzed. The HS pyrolysates changed from isocyanate to amine with increasing temperature. We believe that the newly found pyrolysis behavior of PUEs with different ratios between the HS and SS will promote future studies on the characterization of PUE materials and the pyrolytic recovery of chemical feedstock from PUE wastes. [ABSTRACT FROM AUTHOR]

• Simultaneous removal of HCl, SO 2 , and NO from the mixed gas was performed using MnO 2 /Mg–Al LDH. • Regenerated MnO 2 /Mg–Al LDH could remove HCl, SO 2 , and NO gases. • We efficiently removed the gases from the mixed gas by applying the two-step treatment process. Combustion methods are popularly used to treat acidic exhaust gases to reduce the emission of pollutants. However, exhaust gas treatment can be difficult and expensive, rendering it essential to develop a new treatment process for acidic exhaust gases. In the present study, we investigated the removal of NO from the HCl–SO 2 –NO mixed gas using MnO 2 /Mg–Al layered double hydroxide (MnO 2 /Mg–Al LDH). We analyzed the influence of CO 2 gas on the NO removal. Additionally, we regenerated MnO 2 /Mg–Al LDH after the acid gas adsorption using the wet method and examined the possibility of its cyclical use. MnO 2 /Mg–Al LDH could simultaneously remove HCl, SO 2 , and NO from the mixed gas. Because HCl and SO 2 influenced the NO removal rate, we proposed a two-step treatment process with MnO 2 /Mg–Al LDH and CO 3 •Mg–Al LDH to efficiently remove HCl, SO 2 , and NO from the HCl–SO 2 –NO mixed gas. The NO removal rate decreased with an increase in the CO 2 concentration, confirming the influence of CO 2. Additionally, the results confirmed the possible cyclic use of MnO 2 /Mg–Al LDH after removing acid gases. However, the Mn elution and Mn(IV) concentration decreased the removal rates of SO 2 and NO, respectively. Thus, it is necessary to develop the regeneration method further. [ABSTRACT FROM AUTHOR]

The CLIP1-LTK fusion was recently discovered as a novel oncogenic driver in non-small cell lung cancer (NSCLC). Lorlatinib, a third-generation ALK inhibitor, exhibited a dramatic clinical response in a NSCLC patient harboring CLIP1-LTK fusion. However, it is expected that acquired resistance will inevitably develop, particularly by LTK mutations, as observed in NSCLC induced by oncogenic tyrosine kinases treated with corresponding tyrosine kinase inhibitors (TKIs). In this study, we evaluate eight LTK mutations corresponding to ALK mutations that lead to on-target resistance to lorlatinib. All LTK mutations show resistance to lorlatinib with the L650F mutation being the highest. In vitro and in vivo analyses demonstrate that gilteritinib can overcome the L650F-mediated resistance to lorlatinib. In silico analysis suggests that introduction of the L650F mutation may attenuate lorlatinib-LTK binding. Our study provides preclinical evaluations of potential on-target resistance mutations to lorlatinib, and a novel strategy to overcome the resistance. A novel strategy using gilteritinib can overcome resistance to lorlatinib in non-small cell lung cancer with CLIP1-LTK-L650F mutation. [ABSTRACT FROM AUTHOR]

Chitosan-cellulose composite fibers spun using a Lyocell technology are characterized by a homogeneous distribution and a close packing of the two biopolymers inside the fibrous matrix. Due to the intimate contact of cellulose and chitosan, synergistic effects can be observed during the pyrolysis of the composite fibers. In this study, the catalytic role of chitosan in altering the cellulose pyrolysis pathway in the composite fibers at moderate treatment temperatures up to 900 °C is confirmed. Analyses of the evolved gases during pyrolysis revealed that chitosan promoted cellulose dehydration and substantially decreased the formation of levoglucosan, explaining the higher char yield. The enhanced dehydration reaction is associated with the formation of intermolecular crosslinks due to the incorporation of nitrogen from chitosan in the resulting carbon structures. Nitrogen could also contribute to the in-plane disorder in the aromatic clusters when the pyrolysis is carried out at 500–700 °C, although the in-plane disorder is less noticeable from 700 to 900 °C. Nevertheless, the size of the aromatic cluster continues to grow when the composite fibers are pyrolyzed in a temperature range of 500–900 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

Recycling wood/plastic composites in municipal and industrial wastes currently represents a challenge which needs to be overcome. In this work, we considered the concept of independent pyrolysis of wood and plastic in wood/plastic mixtures for enabling a versatile catalytic process design which is capable of producing recoverable final products from both components. In order to reveal the influence of plastic on wood pyrolysis, the pyrolysis of beech wood (BW, wood material) in a polyethylene (PE) melt (polyolefin material) was performed at 350 °C. The combined use of thermogravimetric analysis, product recovery studies, in situ radical characterisations, and microscopic analysis revealed the influence of the PE melt on the BW pyrolysis. More specifically, a physical prevention of the intermolecular condensation and hydrogen abstraction from PE pyrolysates in the liquid/solid phase was observed. These interactions enhanced the production of levoglucosan and methoxyphenols by factors of 1.7 and 1.4, respectively, during the BW pyrolysis in the PE melt. Based on these results, we concluded that the observed synergistic effects could potentially control the yield and quality of useful products, as well as the utilisation of mixed wood/plastic wastes, which cannot be effectively recycled otherwise. [ABSTRACT FROM AUTHOR]

Recently, layered double hydroxides (LDHs) have been extensively researched for their anion exchange capabilities and exhibit a layered structure with a host layer of octahedrally coordinated metal cations and a guest layer (interlayer) of anions. In this study, we synthesized a CM-β-CD•Zn–Al LDH by anion exchange method to study the anionization of cyclodextrin (CD) to promote its incorporation into the LDH interlayers and its stability therein. Ni2+ adsorption by the CMCD•Zn–Al LDH by the anion exchange method was compared with the results co-precipitation method. The X-ray diffraction spectra of NO3•Zn–Al LDH and CM-β-CD•Zn–Al LDH synthesized by the anion exchange method exhibit that the product peaks were attributable to Z n 6 A l 2 O H 16 C O 3 4 H 2 O and possessed an LDH structure. Furthermore, all CM-β-CD•Zn–Al LDHs exhibited the presence of some CM-β-CD. The CM-β-CD•Zn–Al LDH was hypothesized to be composed of two types of layers: a CM-β-CD layer in which two molecules of CM-β-CD7-, with cavity axes perpendicular to the LDH host layer, are vertically overlaid, and a NO3-type Zn–Al LDH layer used as a precursor. CM-β-CD•Zn–Al LDH adsorbed Ni2+ in an aqueous solution. To determine whether Ni2+ adsorption by the CM-β-CD•Zn–Al LDH is driven chemically or physically, we fitted the data to the Freundlich and Langmuir adsorption models; the results showed that Ni2+ adsorption by the CM-β-CD•Zn–Al LDH is consistent with the Langmuir equation and could be considered a chemical adsorption. [ABSTRACT FROM AUTHOR]

• CO 3 ·Mg–Al LDH can be regenerated by treatment of Cl, SO 4 , NO 3 ·Mg–Al LDH with gaseous CO 2. • The desorption of Cl−, SO 4 2−, and NO 3 − follows the intraparticle diffusion model. • This is limited by the step of CO 3 2− diffusion between LDH layers. Carbonate-intercalated Mg–Al layered double hydroxides (CO 3 ·Mg–Al LDHs) are examined as a means of sequestering gaseous pollutants, such as HCl, NO x , and SO x , which are bound to afford X·Mg–Al LDH (X = Cl, SO 4 , or NO 3). In view of the fact that the common regeneration method of CO 3 ·Mg–Al LDH (agitation in aqueous Na 2 CO 3) poses a number of problems, we herein develop a new method of regenerating CO 3 ·Mg–Al LDH by treatment of X·Mg–Al LDH with gaseous CO 2 under neutral or alkaline conditions. The desorption of X is shown to follow the intraparticle diffusion model, featuring the diffusion of CO 3 2− in between LDH layers as the rate-determining step. Given the importance of LDHs for wastewater treatment and gaseous pollutant removal, the obtained results pave the way to the efficient utilization of these adsorbents and contribute to the development of next-generation decontamination techniques. [ABSTRACT FROM AUTHOR]

With the ultimate aim of reducing the volume of radioactive-cesium-contaminated soil generated by the nuclear power plant accident in Fukushima Prefecture in 2011, this study focuses on the desorption of Cs+ ions from minerals that strongly adsorb Cs+, such as clay, using the ion-association reagents sodium tetrakis(4-fluorophenyl)borate hydrate (NaTFPB) and sodium tetraphenylborate (NaTPB) under mild conditions. A-type zeolite was selected as a representative aluminosilicate mineral with a high cesium adsorption capacity. NaTFPB exhibits stronger hydrophobic interactions with Cs+ and improved Cs+ compared to NaTPB; a desorption efficiency of 89.4% was achieved at a 10:1 NaTFPB/cesium molar ratio. [ABSTRACT FROM AUTHOR]