Catalytic Installation of Primary Amines Onto Polyolefins for Oligomer Valorization.

Polymerization of primary amine-containing monomers is challenging because the amine inhibits polymerization catalyst activity. An alternative approach to access primary amine functionalized polymers is postpolymerization modification. To this end, the hydroaminoalkylation of vinyl-terminated polyolefins with N-(trimethylsilyl)benzylamine is used to prepare primary amine-terminated polyolefins, with the free primary amine substituent being revealed upon hydrolytic work up. These materials are spectroscopically characterized, and an investigation of thermal properties by differential scanning calorimetry and thermogravimetric analysis is completed. These results show that the primary amine substituent increases the glass transition temperature and improves thermal stability. The reactive primary amine functionality is used in the photo-oxidative dimerization of polyolefins to demonstrate how this elusive functionality can be applied in oligomer valorization.

Electrocatalysts for Urea Synthesis from CO2 and Nitrogenous Species: from CO2 and N2/NOx Reduction to urea synthesis.

The traditional industrial synthesis of urea relies on the energy-intensive and polluting process, namely the Haber-Bosch method for ammonia production, followed by the Bosch-Meiser process for urea synthesis. In contrast, electrocatalytic C-N coupling from carbon dioxide (CO2) and nitrogenous species presents a promising alternative for direct urea synthesis under ambient conditions, bypassing the need for ammonia production. This review provides an overview of recent progress in the electrocatalytic coupling of CO2 and nitrogen sources for urea synthesis. It focuses on the role of intermediate species and active site structures in promoting urea synthesis, drawing from insights into reactants' adsorption behavior and interactions with catalysts tailored for CO2 reduction, nitrogen reduction, and nitrate reduction. Advanced electrocatalyst design strategies for urea synthesis from CO2 and nitrogenous species under ambient conditions are explored, providing insights for efficient catalyst design. Key challenges and prospective directions are presented in the conclusion. Mechanistic studies elucidating the C-N coupling reaction and future development directions are discussed. The review aims to inspire further research and development in electrocatalysts for electrochemical urea synthesis.

Atomic/molecular layer deposition strategies for enhanced CO2 capture, utilisation and storage materials.

Elevated levels of carbon dioxide (CO2) in the atmosphere and the diminishing reserves of fossil fuels have raised profound concerns regarding the resulting consequences of global climate change and the future supply of energy. Hence, the reduction and transformation of CO2 not only mitigates environmental pollution but also generates value-added chemicals, providing a dual remedy to address both energy and environmental challenges. Despite notable advancements, the low conversion efficiency of CO2 remains a major obstacle, largely attributed to its inert chemical nature. It is imperative to engineer catalysts/materials that exhibit high conversion efficiency, selectivity, and stability for CO2 transformation. With unparalleled precision at the atomic level, atomic layer deposition (ALD) and molecular layer deposition (MLD) methods utilize various strategies, including ultrathin modification, overcoating, interlayer coating, area-selective deposition, template-assisted deposition, and sacrificial-layer-assisted deposition, to synthesize numerous novel metal-based materials with diverse structures. These materials, functioning as active materials, passive materials or modifiers, have contributed to the enhancement of catalytic activity, selectivity, and stability, effectively addressing the challenges linked to CO2 transformation. Herein, this review focuses on ALD and MLD's role in fabricating materials for electro-, photo-, photoelectro-, and thermal catalytic CO2 reduction, CO2 capture and separation, and electrochemical CO2 sensing. Significant emphasis is dedicated to the ALD and MLD designed materials, their crucial role in enhancing performance, and exploring the relationship between their structures and catalytic activities for CO2 transformation. Finally, this comprehensive review presents the summary, challenges and prospects for ALD and MLD-designed materials for CO2 transformation.

Preparation of Superhydrophobic Surfaces Based on Copper Mesh Substrates and Its Application Performance.

It is not uncommon for metals to corrode, causing the properties of the material to be affected. Superhydrophobic materials have made effective advances in metal corrosion protection because they can effectively insulate liquids from being trapped on metal surfaces. In this study, self-assembled films were formed using octadecanethiol (ODT) modification to obtain superhydrophobic as well as superoleophilic bifunctional materials. With a water contact angle (WCA) of 156°, the material surface exhibits excellent self-cleaning properties. It is also stable in highly corrosive environments. The good hydrophobicity of the material is due to the more tightly arranged conical structure and the ODT coatings of the treated copper mesh surface. The Cassie-Baxter equation calculations showed that the total exposed area of water droplets in air (91.35%) is significantly higher than the area in contact with metal surfaces. This work provides a new strategy for the design of self-assembled surface-modified superhydrophobic materials with excellent performance and stable properties by controlling the chemical composition and morphology of the material surface. The materials are prepared by avoiding cumbersome steps and the use of unusual materials and instrumentation, which allows our designs to greatly reduce the economic costs of time, labor, and raw materials, and to facilitate large-scale industrial preparation and application. The prepared superhydrophobic and superoleophilic synergistic surfaces have excellent self-cleaning properties, wetting stability, anti-corrosive properties, oil-water separation properties, coagulation properties, and durability and have a wide range of applications in the fields of anti-corrosion and seawater desalination.

Harnessing the Power of Microwave Irradiation: A Novel Approach to Bitumen Partial Upgrading.

The partial upgrading of "tar-like" Canadian bitumen is an essential process to reduce its viscosity to an acceptable range that meets the required pipeline specifications. An innovative and potentially greener solution has emerged in the form of microwave irradiation. This work proposes and demonstrates the use of an electrically powered commercial microwave along with carbon-based microwave susceptors (activated carbon, biochar, coke, and graphite) to promote localized thermal cracking within bitumen at a temperature as low as 150 °C, compared to the conventional method of 400 °C. The remarkable results show that just 0.1 wt% of carbon additives can reduce the viscosity of bitumen by 96% with just 10 min of microwaving at 200 °C. A Saturates, Aromatics, Resins, and Asphaltenes (SARA) analysis reveals that the mass fractions of light components (saturates) are almost doubled and that almost one-third of heavy polar hydrocarbon constituents are cracked and decomposed into much lighter molecules, resulting in higher-quality, less viscous bitumen. Furthermore, this study highlights the key role of the surface area and porosity of the carbon microwave susceptor in absorbing microwave radiation, offering exciting new avenues for optimization. Microwave-assisted partial upgrading of bitumen is a cost-effective and eco-friendly alternative to conventional upgrading, producing upgraded bitumen that requires significantly less diluent at a lower cost prior to pipeline transportation.

Plasma-derived exosomal immunoglobulins IGHV4-4 and IGLV1-40 as new non-small cell lung cancer biomarkers.

Exosomal proteins represent valuable research directions in the liquid biopsy of lung cancer (LC). Immunoglobulin subtypes, immunoglobulin molecules with different domains in variable regions, are products of B cell responses to different tumor antigens and are associated with tumor incidence and development. The plasma of patients with LC should theoretically contain a large number of B cell-derived exosomes that specifically recognize tumor antigens. This paper intended to assess the value of the proteomic screening of plasma exosomal immunoglobulin subtypes for diagnosing non-small cell LC (NSCLC). The plasma exosomes of NSCLC patients and healthy control participants (HCs) were isolated using ultracentrifugation. Label-free proteomics was employed to assess the differentially expressed proteins (DEPs), while the biological characteristics of the DEPs were analyzed using GO enrichment. The immunoglobulin content in the top two fold change (FC) values of the DEPs and the immunoglobulin with the lowest P-value were verified using an enzyme-linked immunosorbent assay (ELISA). The differentially expressed immunoglobulin subtypes verified via ELISA were selected to statistically analyze the receiver operating characteristic curve (ROC), after which the diagnostic values of the NSCLC immunoglobulin subtypes were determined via the ROC area under the curve (AUC). The plasma exosomes of the NSCLC patients contained 38 DEPs, of which 23 were immunoglobulin subtypes, accounting for 60.53%. The DEPs were mainly related to the binding between immune complexes and antigens. The ELISA results showed significant differences between the immunoglobulin heavy variable 4-4 (IGHV4-4) and immunoglobulin lambda variable 1-40 (IGLV1-40) in the LC patients and HCs. Compared with the HCs, the AUCs of IGHV4-4, IGLV1-40, and a combination of the two in diagnosing NSCLC were 0.83, 0.88, and 0.93, respectively, while the AUCs for non-metastatic cancer were 0.80, 0.85, and 0.89. Moreover, their diagnostic values for metastatic cancer compared to non-metastatic cancer displayed AUCs of 0.71, 0.74, and 0.83, respectively. When IGHV4-4 and IGLV1-40 were combined with serum CEA to diagnose LC, the AUC value increased, exhibiting values of 0.95, 0.89, and 0.91 for the NSCLC, non-metastatic, and metastatic groups, respectively. Plasma-derived exosomal immunoglobulins containing IGHV4-4 and IGLV 1-40 domains can provide new biomarkers for diagnosing NSCLC and metastatic patients.

[4+1] cyclization of α-diazo esters and mesoionic N-heterocyclic olefins.

Prompted by the recent stepwise mechanistic proposal for the Huisgen [3+2] cycloaddition reaction between enamine and α-diazo ester, where the nucleophilic addition of the enamine carbon onto the terminal nitrogen of diazo ester is crucial, we examined the possible use of N-heterocyclic olefins (NHOs) as highly electron-rich dipolarophiles in these reactions. The mesoionic NHOs derived from 1,2,3-triazoles undergo fast [4+1] cycloaddition to give 3-(triazolium-4-yl)-(3H)-pyrazol-4-olates at room temperature. The reaction mechanism has been explored through experimental and DFT computational studies.

Transmembrane TNF-α as a Novel Biomarker for the Diagnosis of Cytokine Storms in a Mouse Model of Multiple Organ Failure.

A cytokine storm (CS) is an out-of-control inflammatory response closely associated with the progression of diseases, such as multiple organ failure (MOF), severe sepsis, and severe or critical COVID-19. However, there is currently a lack of reliable diagnostic markers to distinguish CS from normal inflammatory responses. Tumor necrosis factor-α (TNF-α) includes transmembrane TNF-α (tmTNF-α) and secreted TNF-α (sTNF-α). The MOF mouse model in this study showed that the tmTNF-α expression changes in the neutrophils differed from the serum TNF-α and serum IL-18, INF-γ, IL-4, and IL-6. Furthermore, tmTNF-α, instead of serum TNF-α, IL-18, INF-γ, IL-4, and IL-6, reflected liver and kidney tissue damage and increased with the aggravation of these injuries. Analysis of the ROC results showed that tmTNF-α effectively distinguished between inflammatory responses and CS and efficiently differentiated between surviving and dead mice. It also significantly improved the diagnostic value of the traditional CRP marker for CS. These results indicated that the tmTNF-α expressed in the neutrophils could be used to diagnose CS in MOF mice, providing an experimental basis to further develop tmTNF-α for diagnosing CS patients.

Therapeutic effect of modified zengye decoction on primary Sjogren's syndrome and its effect on plasma exosomal proteins.

Background: Modified Zengye Decoction (MZD), a traditional Chinese medicine, is an effective treatment for patients with primary Sjögren's syndrome (pSS). Purpose: To evaluate the efficacy of MZD and investigate its effect on plasma exosomal proteins. Methods: Eighteen pSS patients were treated with MZD for 2 weeks. The therapeutic effect was evaluated by observing the changes in clinical symptoms, laboratory parameters, and plasma cytokines before and after treatment. Then, the differentially expressed proteins (DEPs) in the plasma exosomes before and after treatment were identified via label-free proteomics, while Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were used to analyze the possible biological functions and signaling pathways involved in the exosomal DEPs. Results: MZD can effectively relieve the clinical symptoms of pSS patients, downregulate the plasma IgG and IgM levels, and inhibit plasma cytokine production. Thirteen DEPs were identified via label-free proteomics in the plasma exosomes before and after MZD treatment, of which 12 were downregulated proteins. GO analysis showed that these downregulated proteins were mainly related to the insulin response involved in dryness symptoms and the Gram-negative bacterial defense response and proteoglycan binding involved in infection. KEGG enrichment analysis showed that these downregulated proteins were primarily associated with the porphyrin metabolism involved in oteoarthrosis and the NF-κB and TLR4 pathways involved in infection. Conclusion: MZD can effectively alleviate SS symptoms, while its mechanism may be associated with the reduced protein expression in insulin response, porphyrin metabolism, and the TLR4/NF-κB pathway.

Constructing fused N-heterocycles from unprotected mesoionic N-heterocyclic olefins and organic azides via diazo transfer.

Mesoionic N-heterocyclic olefins (mNHOs) were first reported last year and their reactivity remains largely unexplored. Herein we report the reaction of unprotected mNHOs and organic azides as a novel synthetic route to a variety of pyrazolo[3,4-d][1,2,3]triazoles, an important structural motif in drug candidates and energetic materials. The only byproduct aniline can be easily recycled and converted back to the starting organic azide, in compliance with the green chemistry principle. The reaction mechanism has been explored through experimental and computational studies.