Chemical Papers最新文献

Waste management and production of value-added chemicals were carried out by pyrolysis of chromium leather waste using CaO obtained from marble waste. The CaO was characterized by XRD, SEM, TGA, and BET techniques, and the analysis of pyrolysis experiment products in the presence/absence of CaO were characterized/detected by FT-IR, elemental, GC–MS, and micro-GC–MS, and calorific value analysis. The effects of pyrolysis temperature, N₂ flow rate, heating rate, retention time and CaO amount on the yield of the obtained liquid product (bio-oil) were investigated. In addition, the effect of the catalyst on the gas product composition was also determined. The highest liquid product yield were obtained without CaO 35.5% and with CaO 49% in the pyrolysis temperature 500 ºC, nitrogen gas flow rate 0.50 L·min⁻¹, heating rate 50° L·min⁻¹, and retention time 20 min. Moreover, the deoxygenation during pyrolysis increased the C/O ratio in the liquid product composition and, consequently, the calorific value (up to 13%). In addition, while the amount of CO₂ among the gaseous products formed during pyrolysis decreased from 38 to 1% due to capture by the CaO, the increase in the amounts of H₂ and acetylene was approximately two-fold and 30-fold, respectively. So, the pyrolysis of leather/marble waste is a viable process that can enhance the quality of pyrolysis products, and prevent possible environmental pollution.

Recently, Pt-free counter electrodes (CEs) have emerged as cost-effective alternatives for components in dye-sensitized solar cells (DSSCs), garnering significant interest in the field. In this regard, we have developed a novel hybrid composite consisting of 2D spinel phase CdFe₂O₄ and 2D reduced graphene oxide (rGO) nanosheets through a one-step ultrasonic-assisted hydrothermal method to serve as the CE for dye-sensitized solar cells. The crystallinity, morphology and textural properties of the composites were analyzed in detail using X-ray diffraction, scanning electron microscopy (FE-SEM), Transmission electron microscope, N₂ adsorption–desorption, X-ray photo electron spectroscopy techniques. The findings obtained through electrochemical impedance spectroscopy, cyclic voltammetry and Tafel polarization measurements indicated that the CdFe₂O₄/rGO demonstrated robust electrocatalytic activity, enabling effective I⁻/I₃⁻ redox reactions and notably reduced charge transfer resistance in comparison with pristine CdFe₂O₄. Specifically, the DSSC utilizing the CdFe₂O₄/rGO CE attains a power conversion efficiency of 8.52%, significantly surpassing the efficiencies of 4.02%, 5.21%, and 6.64% observed in solar cells employing CdFe₂O₄, CdFe₂O₄-rG1, and CdFe₂O₄-based counter electrodes, respectively. Therefore, the CdFe₂O₄/rGO hybrid composite serves as a cost-effective alternative to high-cost Pt as a CE, thereby facilitating cost-efficiency in DSSCs in the future.

Regenerated protein fibers with different biogenetic derivations greatly vary in cost. However, finding a proper method for identifying and quantitating regenerated protein fibers is difficult. This study developed a rapid, inexpensive, convenient, and accurate qualitative immunochromatography method to detect regenerated casein fiber (RCF) in textiles. The RCF was characterized by electrospray ionization/time of flight mass spectrometry. Peptide haptens were designed based on an inert, conserved, and immunogenic sequence of regenerated casein. Monoclonal antibodies were prepared from the haptens, and a colloidal gold immunochromatography assay (GICA) was applied for the detection. A limit of detection of 0.1% RCF in textiles was achieved with a total analysis time of only 15 min using an extraction solution of 7 M urea containing 0.1% dithiothreitol and treatment for 10 min in boiling water. Quantitative assay results were obtained by using a GICA reader with the recovery rates of 110 to 130% and relative standard deviations of ≤ 20%.

In recent years, the exploration of natural compounds for their therapeutic potential has gained considerable attention, with xanthones emerging as promising candidates due to their diverse biological activities including anti-inflammatory properties. This comprehensive review delves into the synthesis and evaluation of synthetic xanthone derivatives as potential anti-inflammatory agents. The review commences by introducing the structural characteristics and chemical diversity of synthetic xanthone derivatives, highlighting the various methods used to synthesize them. It then delves into the mechanisms underlying the anti-inflammatory effects of synthetic xanthone derivatives, focusing on their interactions with key pathways involved in inflammation. Furthermore, the review explores the relationships between the structure of synthetic xanthones and their anti-inflammatory potential, shedding light on critical structural elements responsible for their efficacy. In summary, this review consolidates our existing knowledge about synthetic xanthone derivatives as a class of compounds with remarkable anti-inflammatory properties. It underscores the importance of further research to fully understand how they work, improve their pharmacological properties, and assess their clinical benefits. Synthetic xanthone derivatives show immense promise in the search for new anti-inflammatory therapeutics, making them a compelling subject for future drug development endeavors.

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This new investigation focused on the creation of a novel hexafunctional epoxy resin by synthesizing a two-tier aromatic radical matrix containing bonds such as C = C, C–N, C–C, and P = O. The initial step involved obtaining the precursor molecule for the epoxy matrix, which was subsequently functionalized with epichlorohydrin. The resin was meticulously characterized using Fourier transform infrared and nuclear magnetic resonance spectroscopy, which revealed its structure at a microscopic level. Concurrently, the viscosity parameters were analyzed to have a better understanding of the resin's flow properties. Epoxy resin is widely recognized as a superior protective agent due to its distinct electron donor and acceptor sites. The properties of phosphoric ester hexaglycidyl para-amino phenol resin (HGPAPEP) were carefully studied to determine its potential as a protective agent. At 298 K, Carbon steel was immersed in 1.0 M of hydrochloric acid at 298 K. Surface inspection was carried out using electrochemical techniques and scanning electron microscopy/energy dispersive spectroscopy. The data show that HGPAPEP has remarkable corrosion-inhibiting characteristics in hydrochloric acid. Potentiodynamic polarization and electrochemical impedance spectroscopy revealed an excellent 95.90% efficiency at 10^–3 M. Isothermal adsorption experiments established that our protective compound follows the Langmuir adsorption model. The Gibbs adsorption free energy (ΔG_ads) value of −44.24 kJ/mol suggests that the protective agent molecules form a chemical bond with the electrode surface, resulting in excellent corrosion protection. A theoretical study reinforced this surface analysis, verifying our experimental results.

In order to overcome burgeoning energy demands along with the ecological crisis caused by dwindling amounts of fossil fuel and increasing levels of carbonaceous emission, there is an immediate need to develop economical, eco-friendly systems for energy applications. To overcome this issue, use of non-carbon materials has been suggested, but their commercial usage is limited due to intermittency and high operational costs. Currently, layered double hydroxides (LDHs) are prospective contenders for energy applications by virtue of unique physicochemical properties and excellent theoretical specific capacitance. Additionally, LDH–polymer matrix composites (PMCs) have also emerged as nexus materials in energy storage sector since they surpass disadvantages of both LDHs and polymers and broaden the horizons for their practical applications. The current review highlights applications of LDH–PMCs as supercapacitors in terms of maximum specific capacitance, energy density, power density, and rate capability along with insights into mechanism of capacitance, thereby outlining their utility in energy storage.

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Low limit of detection (LOD), high sensitivity and selectivity are essential performance criteria of a sensor. As the naturally occurring uranyl ion (U⁶⁺) is toxic, a sensor with suitable performance parameters for measuring U⁶⁺ in drinking water is of interest. In this work, four aspects of the detection of U⁶⁺ are presented. First, a composite synthesized from aniline, N-phenylglycine and graphene oxide (GO) was used for the first time to detect the uranyl ion. Second, the ligand 2-(5-bromo-2-pyridylazo)-5-(diethylamino) phenol (BromoPADAP) was used as a ligand, attached at the composite surface, functionalized with diamine (Design I) and also as a complexing agent in the electrolyte (Design II), and a comparative study for both the cases was conducted. The parameters for comparison were the sensitivity, LOD and interference from several test ions. It was found that for Design I, the LOD was 50 ppt, while for Design II the LOD was 8 ppb. Next, the interference phenomena were explained by the conventional peak reduction (PR) technique and the barrier width (BW) technique. The BW technique was used for the first time to scale the interference of test ions toward the target analyte Cd²⁺, as in our previous works. PR technique requires a higher number of tests, while the BW technique employs a couple of tests, thus minimizing the effort. In this work, the BW technique supported the PR technique results in predicting the interference behavior. Finally, the BW technique was used to explain the difference in Design I and II results.

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The article reviews the latest advances in integrated CO₂ capture and utilization (ICCU), which presents several benefits over conventional carbon capture and utilization. A variety of ICCU processes based on homogeneous adsorption and catalytic systems, as well as heterogeneous materials are reviewed critically in the article. Due to the varying configurations of adsorption and catalytic processes in the ICCU process, heterogeneous materials can be utilized in various forms, including the superposition of adsorbent and catalyst, physical mixing and the use of dual-functional materials. The development of various bifunctional materials that are eco-friendly, simple to regenerate, and consume less energy for integrated CO₂ capture and reverse water–gas shift reaction (ICCU-RWGS), integrated CO₂ capture and dry reforming of methane (ICCU-DRM), and integrated CO₂ capture and methanation (ICCU-Methanation) has also been investigated. A detailed discussion has also been conducted on the selection of components and the effect of operating parameters to synthesize bifunctional materials. Additionally, in order to consider large scale industrial applications this review also included techno-economic and environmental assessments of ICCU. The review concluded that Compared to carbon capture and storage and carbon capture and utilization, ICCU offers advantages in terms of technology, economy, and the environment.

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Failure in manufacturing, aerospace, marine, construction, and locomotive industries often stems from issues like fracture, corrosion, wear, distortion, and erosion. This research investigates the failure of railway composite brake block materials in different environments. Tests were conducted on used composite brake blocks in three media: 1.75% and 3.5% wt NaCl, 0.5 M and 1 M HCl and H₂SO₄. Corrosion analysis utilized linear polarization and open circuit techniques with a potentiostat/galvanostat. Microstructure, crystallography, and hardness were characterized using SEM/EDS, X-ray diffraction, and a digital superficial Brinell hardness tester. Results showed a hardness of 238.3 kgf/mm² for the controlled sample, 236.8 kgf/mm² for NaCl, and lower values of 233.4 kgf/mm² and 233.6 kgf/mm² for HCl and H₂SO₄, respectively. Corrosion rates were highest in acidic media, with 5.2390 mm/year for H₂SO₄ and 5.1342 mm/year for HCl, compared to 2.51662 mm/year in NaCl. SEM/EDS analysis revealed pronounced pitting in acidic media and uniform pits in chloride media. Phase formation indicated the presence of chloride halides and sulfide compounds like Fe(OCl) and C₂(Fe, Na)CuCl. The primary components of the brake block were iron, silicon, aluminum, and carbon. Acidic environments accelerate failure due to weak bonding in the composite, while chloride systems demonstrate higher stability in rail applications.

Chemotherapy plays a role in many cancer therapies, including breast cancer, but due to its significant side effects, alternate treatment approaches have been investigated. One such alternative is photodynamic therapy (PDT), which employs a combination of oxygen, a photosensitizer (PS), and light of a specific wavelength. Transition metal complexes and SBL have gained interest in PDT. In this study aimed to assess the potential antitumor activity and underlying mechanism of a newly synthesized Schiff base ligand (SBL)-mediated PDT on MCF-7 cells, comparing its efficacy to cisplatin. We synthesized and characterized two novel Pd-conjugated SBL compounds (complex-1 and 2). Following the treatment of MCF-7 cells with these compounds, a light-emitting diode (LED) was utilized to deliver a light dose of 14.8 J/cm². In MCF-7 cells, we also looked at cytotoxicity, cell death rates, and ROS levels. Results indicated a significant increase in cytotoxicity (IC₅₀:12.5 µM) (p < 0.05) and ROS levels (258.33%) (p < 0.05) in the group treated with complex-1-mediated PDT compared to control. The late apoptotic (29.78%) (p < 0.05) and necrotic (24.23%) (p < 0.05) cell death also increased significantly compared to the control group (1.86 ± 0.92, 1.89 ± 0.32, respectively). In conclusion, our study suggests that the complex-1 compound may serve as a promising candidate for anticancer agents in PDT for MCF-7 cells. In contrast, complex-2-mediated PDT did not demonstrate any observable anticancer activity.