Hasil untuk "Chemical engineering"

G. Skačej, P. Ziherl

H. Yoo, Taek-Gyoung Kim, T. Park

L. Ghasemi‐Mobarakeh, M. Prabhakaran, M. Morshed et al.

J. Mano, G. Silva, H. Azevedo et al.

The fields of tissue engineering and regenerative medicine aim at promoting the regeneration of tissues or replacing failing or malfunctioning organs, by means of combining a scaffold/support material, adequate cells and bioactive molecules. Different materials have been proposed to be used as both three-dimensional porous scaffolds and hydrogel matrices for distinct tissue engineering strategies. Among them, polymers of natural origin are one of the most attractive options, mainly due to their similarities with the extracellular matrix (ECM), chemical versatility as well as typically good biological performance. In this review, the most studied and promising and recently proposed naturally derived polymers that have been suggested for tissue engineering applications are described. Different classes of such type of polymers and their blends with synthetic polymers are analysed, with special focus on polysaccharides and proteins, the systems that are more inspired by the ECM. The adaptation of conventional methods or non-conventional processing techniques for processing scaffolds from natural origin based polymers is reviewed. The use of particles, membranes and injectable systems from such kind of materials is also overviewed, especially what concerns the present status of the research that should lead towards their final application. Finally, the biological performance of tissue engineering constructs based on natural-based polymers is discussed, using several examples for different clinically relevant applications.

Honglai Li, Xidong Duan, Xueping Wu et al.

Ahmed Ben Ali, Nosiba Mohamed Ahmed, Saeed Al-Meer et al.

This study develops agar-based hydrogels for treating complex high-salinity mixed oil effluent (MOE) containing organic and inorganic contaminants. Hydrogels were synthesized via microwave-assisted free-radical polymerization, grafting agar with acrylamide at various loadings. The AgAM series varied acrylamide from 10-30 g, while the AgCr series had a fixed agar-to-acrylamide ratio of 1:20 (w/w) and was crosslinked with N, N'-methylenebisacrylamide. FTIR, TGA, and SEM confirmed successful grafting, improved thermal stability, and porous morphology. The AgCr5% sample removed 24-27% COD with an adsorption capacity of 628 mg/g, and 58.5% oil and grease at 10 g/L, with metal ion removal improving at 50 g/L. Kinetic studies showed oscillatory adsorption-desorption, supported by Weber-Morris diffusion analysis indicating multiple rate-limiting steps. Temperature impacts (25-55°C) were minimal, suggesting energy efficiency. The hydrogel performed through 7 regeneration cycles with performance decline. SEM revealed contaminant entrapment and decreasing pore size from 7.98 to 2.97 μm. FTIR and XPS confirmed interactions like hydrogen bonding, electrostatic attraction, and complexation via functional groups. These results indicate agar-based hydrogels are sustainable, multifunctional adsorbents for removing diverse contaminants from industrial wastewater, suitable for pretreatment before advanced polishing.

Jacem Zidani, Latifa Tajounte, Abdellah Benzaouak et al.

The review highlights the advancements in flexible lead-free piezoelectric materials, emphasizing their potential for energy harvesting and sustainable energy. Although normal piezoelectric materials such as lead zirconate titanate (PZT) have great efficiency, their lead content causes environmental issues. This research focuses on replacement materials like biodegradable polymers and bismuth sodium titanate (BNT), which not only show interesting piezoelectric capabilities but also have advantages in terms of flexibility and biocompatibility. In order to increase piezoelectric performance while maintaining flexibility, it is advised to include inorganic fillers into polymer matrices, therefore qualifying these materials for usage in biomedical and wearable electronics applications. The evaluation also covers the issues resulting from the great usage of these resources, including e-waste and the need of sustainable solutions. The general message of the research underlines the need of developing new piezoelectric materials able to effectively gather mechanical energy from different sources, therefore promoting self-sustaining systems and reducing reliance on traditional power sources. The review also underlines how lead-free piezoelectric materials can boost power density and chemical oxygen demand (COD) removal rates in microbial fuel cells (MFCs), therefore promoting sustainable energy solutions that turn organic waste into bioelectricity.

Dacheng Zheng, Rui Huang, Haichuang Lan

In this work, a Zn2+ fluorescent probe based on quinoline was designed and synthesized. The flexible diethanolamine was attached to 8-Hydroxyquinoline-2-carboxaldehyde, forming a well-dissolved and biocompatible fluorescent probe. As a recognition group, the diethanolamine not only maintained selectivity for zinc ions, but also had good anti-interference ability to pH. The synthesis process of the probe (QE) was described in detail and characterized by 1H, 13C and HRMS. The sensing performance (pH stability, response time, and detection limit) of the probe for zinc ions in buffer solution PBS and live human gingival fibroblasts was extensively investigated. This pH-resistant probe provided a powerful tool for studying the synergistic effect of drugs and zinc ions.

Jiaxin Zhao, Huiying Zhou, Rui Wu et al.

Introduction and Objectives: This study aimed to investigate the association between biological aging and liver fibrosis in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). Materials and Methods: We analyzed NHANES 2017–2020 data to calculate phenotypic age. Hepatic steatosis and fibrosis were identified using controlled attenuation parameters (CAP), fatty liver index (FLI) and transient elastography (TE). The odds ratios (ORs) and 95 % confidence intervals (CI) for significant MASLD fibrosis were calculated using multivariate logistic regression, and subgroup analyses were performed. We explored the potential causal relationship between telomere length and liver fibrosis using Mendelian randomization (MR). Additionally, we used the expression quantitative trait loci (eQTL) method and GSE197112 data to identify genes related to liver fibrosis and senescence. Finally, the APOLD1 expression was validated using GSE89632. Results: Phenotypic age was associated with liver fibrosis occurrence in MASLD (OR = 1.08, 95 % CI 1.05–1.12). Subgroup analyses by BMI and age revealed differences. For obese or young to middle-aged MASLD patients, phenotypic age is significantly associated with liver fibrosis. (OR = 1.14, 95 % CI 1.10–1.18; OR = 1.07, 95 % CI 1.01–1.14 and OR = 1.14, 95 % CI 1.07–1.22). MR revealed a negative association between telomere length and liver fibrosis (IVW method: OR = 0.63288, 95 % CI 0.42498–0.94249). The gene APOLD1 was identified as a potential target through the intersection of the GEO dataset and eQTL genes. Conclusions: This study emphasized the link between biological aging and fibrosis in young to middle-aged obese MASLD patients. We introduced phenotypic age as a clinical indicator and identified APOLD1 as a potential therapeutic target.

Kaustav Das, Ishita Ghosh, Soumalya Chakraborty et al.

Abstract Altering surface chemistry of functional materials is an attractive route to enable large property enhancements without sacrificing overall structural-order, appealing to diverse fields of application sciences; however, the same remains unexplored for organic crystalline materials. Herein, piezoelectricity in pharmaceutical crystals is reported to show colossal surface charges driven by mechanical fracture — where a collection of dipoles arranged in polar head-to-tail fashion generates opposite surface charges on freshly fractured faces — causing them to actuate large distances over 75 µm in milliseconds. Kelvin probe force microscopy is leveraged to show many-fold surface potential enhancement in fractured surfaces relative to the pristine crystals. Further, complementarity of the surface potentials in a pair of fractured crystal shards and asymptotic decay behaviour with time are observed. Newly formed surfaces of the pharmaceutical crystals show long-lasting charges despite their relatively lower piezo-response confirmed by bulk piezometry. To establish the generality of surface phenomena, statistical analyses (≈50 samples) of post-fracture-attraction behaviour of crystals are performed. Finally, the application of fracture-driven surface charges in industrial processes is achieved by investigating flow-property and tablet-strength of bulk pharmaceutical materials. This multiscale approach unveils the symmetry-dependency of surface charges in fractured materials, and probes the same for utilisation in bulk-property engineering.

Omar Salmi, Fabio Pastori, Marco Marinsalta et al.

Powertan is a disrupting new approach for leather tanning were the penetration inside the hide to be tanned is enhanced by the use of an externally applied electric field. Thus, the penetration is no longer controlled by the fickian diffusion mechanism by ion migration.The result is a dramatical decrease of the process time, from the almost 24 h of the traditional drum operation to few minutes. Moreover, the electric field reduces the necessity of ancillary operations like the pickling and the basification with a reduction to about one tenth of the bath/leather ratio from the about 20 L/kg. Here, the first small scale batch tests will be presented with a preliminar modeling interpretation.

Ali A. Ali, Ghassan Hameed Abdul-Majeed, Abdalellah O. Mohmmed

   The solubility of asphaltenes in crude oils is predominantly influenced by variations in temperature, pressure, and oil composition. These alterations can precipitate asphaltene deposition, resulting in diminished permeability, obstruction of wells and auxiliary surface facilities, and ultimately, a reduction or cessation of production. Therefore, it is imperative for upstream and downstream processing engineers to comprehend and predict asphaltene phase behavior to implement effective preventative and remedial strategies and minimize costs. Asphaltene precipitation can be predicted through the application of solubility and colloidal theories. In this study, cubic equations of state and cubic-plus-association equations of state are utilized as solubility theory-based methodologies. The advanced versions of the Peng-Robinson (APR78) and Soave-Redlich-Kwong (ASRK) cubic equations of state are compared with cubic-plus-association (CPA) equations of state using Multiflash software to predict fluid and asphaltene phase behavior. The simulation results demonstrate a strong correlation between the ASRK model and the CPA model, with a minor deviation from the results of the APR78 model. This observation suggests that these models can effectively predict asphaltene behavior and yield acceptable results when compared to experimental data for fluid and asphaltene. Considering the likelihood of asphaltene deposition within wells, hence, it is recommended to develop a model to determine the locations and quantities of deposition.

Yu Liu, Tao Liu, Danfeng Jiang

Sweat contains a wealth of health-related biomarkers, which has been a promising resource for personalized real-time monitoring at molecular level. Emergence of non-enzymatic electrochemical sensor that simulates the enzyme catalysis utilizing the functional material further promotes the development of wearable sweat sensor, successfully addressing the limitations of enzyme sensing in sensitivity and stability. Thus, there is an urgent need for centering on the regulation of the nanostructure, combination and preparation method of functional materials to enhance the catalytic activity for enzyme-free detection of sweat biomarkers. This review aims to present the superiors of enzyme-free sensing on wearable sweat sensor, and provides guidance for material innovation, sensor design and system integration. Firstly, we primarily focus on the recent advances of novel functional nanomaterials in wearable non-enzymatic electrochemical sensor, and briefly describe the sensing principles for detecting biomarkers in sweat. Subsequently, the correlation between the electrochemical strategy and functional material is elaborately interpreted by coupling with the diverse molecular structures of the biomarkers and the pH changes of test environments. Finally, challenges and opportunities for wearable non-enzymatic electrochemical sensor in sweat sensing are delineated in the development of future personalized healthcare.

Md. Arif Hossen, Fatema Khatun, Riyadh Ramadhan Ikreedeegh et al.

Photocatalytic CO₂ reduction into hydrocarbon fuels is one of the most efficient processes since it serves as a renewable energy source while also lowering atmospheric CO₂ levels. The development of appropriate materials and technology to attain greater yield in CO₂ photoreduction is one of the key issues facing the 21st century. This study successfully fabricated novel ternary reduced graphene oxide (RGO)/Au-TiO₂ nanotube arrays (TNTAs) photocatalysts to promote CO₂ photoreduction to CH₄. Visible light-responsive RGO/Au-TNTAs composite was synthesized by facile electrochemical deposition of Au nanoparticles (NPs) and immersion of RGO nanosheets onto TNTAs. The synthesized composite has been thoroughly investigated by FESEM, HR-TEM, XRD, XPS, FT-IR, UV-Vis DRS, and PL analyzer to explain structural and functional performance. Under the source of visible light, the maximum yield of CH₄ was attained at 35.13 ppm/cm² for the RGO/Au-TNTAs composite photocatalyst after 4 h, which was considerably higher by a wide margin than that of pure TNTAs, Au-TNTAs and RGO-TNTAs. The CO₂ photoreduction of the RGO/Au-TNTAs composite has been improved due to the combined effects of Au NPs and RGO. Due to its surface plasmonic resonance (SPR) mechanism, Au NPs play a crucial role in the absorption of visible light. Additionally, the middle RGO layers serve as effective electron transporters, facilitating better separation of electron-hole pairs. The newly constructed composite would be a promising photocatalyst for future photocatalytic applications in other fields.

J. Carberry

Andrea Maffini, Giorgio Bonvicini, Alessandro Venturin et al.

Purpose of this paper is to outline a framework for resources and energy efficiency auditing activities and present its application in field studies carried out in Italy and in Eastern Europe, to support Companies and International Financial Institutions (IFIs) in the implementation of actions to improve industrial performances and reduce global environmental impacts. Among environmental considerations, climate change mitigation and adaptation aspects are included, as well as circular economy, pollution prevention and preservation of biodiversity. Within this context, this study focuses on the peculiar case of the textile industry, which is characterized by a significant use of energy and resources, mainly water and chemicals, thus involving the respect of the Zero Discharge of Hazardous Chemicals Programme. The auditing approach is conceived as a step-by step sequence of activities, starting from the Job Assignment from the Client based on specific Terms of Reference, followed by the submission of a data collection questionnaire, tailored to the specific textile industry, site survey with company managers and concluded with the elaboration of the technical report. In order to demonstrate the capability of the approach, the applicative section of this paper will present results in terms of technical and managerial actions to reduce energy and water consumption and GHGs emissions, as well as to control water pollution and waste generation and disposal.

Shuyu Tian, Rory Stevens, Bridget T. McInnes et al.

Optimization of extrusion-based bioprinting (EBB) parameters have been systematically conducted through experimentation. However, the process is time- and resource-intensive and not easily translatable to other laboratories. This study approaches EBB parameter optimization through machine learning (ML) models trained using data collected from the published literature. We investigated regression-based and classification-based ML models and their abilities to predict printing outcomes of cell viability and filament diameter for cell-containing alginate and gelatin composite bioinks. In addition, we interrogated if regression-based models can predict suitable extrusion pressure given the desired cell viability when keeping other experimental parameters constant. We also compared models trained across data from general literature to models trained across data from one literature source that utilized alginate and gelatin bioinks. The results indicate that models trained on large amounts of data can impart physical trends on cell viability, filament diameter, and extrusion pressure seen in past literature. Regression models trained on the larger dataset also predict cell viability closer to experimental values for material concentration combinations not seen in training data of the single-paper-based regression models. While the best performing classification models for cell viability can achieve an average prediction accuracy of 70%, the cell viability predictions remained constant despite altering input parameter combinations. Our trained models on bioprinting literature data show the potential usage of applying ML models to bioprinting experimental design.

R. Kazlauskas

T. Fuller, J. Harb

From chemical and electronics manufacturing, to hybrid vehicles, energy storage, and beyond, electrochemical engineering touches many industries—any many lives—every day. As energy conservation becomes of central importance, so too does the science that helps us reduce consumption, reduce waste, and lessen our impact on the planet. Electrochemical Engineering provides a reference for scientists and engineers working with electrochemical processes, and a rigorous, thorough text for graduate students and upperdivision undergraduates.

Fengxu Wu, Linsheng Zhuo, Fan Wang et al.

Summary: Motivated by the growing demand for reducing the chemical optimization burden of H2L, we developed auto in silico ligand directing evolution (AILDE, http://chemyang.ccnu.edu.cn/ccb/server/AILDE), an efficient and general approach for the rapid identification of drug leads in accessible chemical space. This computational strategy relies on minor chemical modifications on the scaffold of a hit compound, and it is primarily intended for identifying new lead compounds with minimal losses or, in some cases, even increases in ligand efficiency. We also described how AILDE greatly reduces the chemical optimization burden in the design of mesenchymal-epithelial transition factor (c-Met) kinase inhibitors. We only synthesized eight compounds and found highly efficient compound 5g, which showed an ∼1,000-fold improvement in in vitro activity compared with the hit compound. 5g also displayed excellent in vivo antitumor efficacy as a drug lead. We believe that AILDE may be applied to a large number of studies for rapid design and identification of drug leads.