Hasil untuk "Chemical technology"

Md Imran Hasan, Gang Lei, Dylan Lu et al.

Electric vehicle (EV) adoption is generating a rapidly increasing stream of retired lithium-ion batteries for second-life deployment. However, thermal safety concerns continue to limit their reuse. This paper reviews second-life battery (SLB) thermal safety and management and organizes existing work through a mechanism-to-deployment framework linking four domains: degradation mechanisms, cell screening, pack configuration, and monitoring. Evidence indicates that thermal risk depends on the degradation pathway rather than capacity fade. In fact, cells with comparable capacity can exhibit substantially different trigger temperatures depending on whether lithium plating or solid-electrolyte interphase (SEI) growth dominates. Therefore, capacity-based screening is insufficient because cells that satisfy capacity thresholds may still remain thermally unstable. The four domains are tightly coupled: the degradation pathway determines screening requirements; screening outcomes constrain pack design; pack topology influences fault escalation; and together these factors determine what monitoring can reliably detect. This review highlights three gaps and outlines future research directions in the field of SLB thermal safety and management: limited aged-cell thermal characterization by degradation pathway, insufficient diagnostic validation under industrial-throughput conditions, and the incomplete translation of screening outputs into design rules.

Shuxin Li, Wenfei Shen, Shuhan Guo et al.

Considered a pivotal advancement for commercial applications, blade coating technology for large area photovoltaic devices has emerged as a forefront research area in the field of polymer solar cells (PSCs). Herein, a high-performance PM6:L8-BO device is fabricated with the blade-coating method in ambient air. Meanwhile, Eu3+-induced diblock polymer aggregates (EIPAs) and Tb3+-induced diblock polymer aggregates (TIPAs) with excellent fluorescent properties were synthesized through self-assembly and incorporated as an additive into the PM6:L8-BO system to increase the ultraviolet light absorption and enhance BC-PSC light harvesting. By employing this strategy, the blade-coating device's power conversion efficiency (PCE) was improved from 12.25 % to 13.63 %, and the relative efficiency was enhanced by 11.3 %. In addition to the performance improvement, the stability of the devices was also enhanced by 19 %, indicating the effectiveness of this approach in producing more efficient and durable PSCs.

Pablo Rodríguez-Hernández, Nieves Núñez-Sánchez, Silvia Molina-Gay et al.

Milk is one of the most important foods in the human diet. Its composition and quality may be compromised by bovine mastitis, which is currently the most serious disease affecting dairy cows due to its economic and productive impact. Subclinical bovine mastitis (SBM) is particularly problematic due to no obvious visible symptoms, which hamper the current diagnosis and lead to an underestimation of its impact. Since mastitis is the primary reason for antibiotic use in dairy production, there is a growing focus on a selective therapy, based on the management of the disease by treating only those cases that will benefit from antibiotics. However, the discrimination of these cases remains a major challenge. The objective of this study was to evaluate near infrared spectroscopy (NIRS) analysis of milk samples as a screening method to discriminate SBM aetiology and promote pathogen-based therapy using predictive models. Individual milk samples from 101 Holstein-Friesian cows across 29 herds were collected, subjected to somatic cell count, microbiological culture, and biochemical tests to identify the bacterial species involved. Subsequently, these samples were analysed by NIRS, and the resulting spectral information was used to design different predictive models. Notable differences were noticed among the spectra of the groups compared. The model classification or prediction success ranged from 85.71 % to 95.24 %, with high sensitivity (88.89–100 %) and specificity (81.82–90.91 %). These preliminary data highlight the usefulness of spectral information obtained from NIRS analysis of milk. The proposed approach holds potential as a screening methodology to provide a fast diagnostic result of SBM and promote a pathogen-based therapy to prevent milk quality losses and public health issues. Increasing sample variability in future studies is considered of paramount importance to achieve reliable performance of predictive models.

Guanzhou Di, Chen Lu, Mengting Xue et al.

ObjectivesRetinal pigment epithelium (RPE) cell transplantation holds therapeutic promise for retinal degenerative diseases, but longitudinal monitoring of graft survival and efficacy remains clinically challenging. The aim of this study is to develop a simple and effective method for the therapeutic quantification of RPE cell transplantation and immune rejection in vivo.MethodsA nanoprobe was developed and modified to label donor RPE cells, and used to monitor the position and intensity of the fluorescence signal in vivo. Immunofluorescence staining and single-cell RNA sequencing (scRNA-seq) were used to characterize the cell types showing the fluorescence signal of the nanoprobe and to determine the composition of the immune microenvironment associated with subretinal transplantation.ResultsThe spatial distribution of the fluorescence signal of the nanoprobe corresponded with the site of transplantation, but the signal intensity decreased over time, while the signal distribution extended to the choroid. Additionally, the nanoprobe fluorescence signal was detected in the liver and spleen during long-term monitoring. Conversely, in mice administered the immunosuppressive drug cyclosporine A, the decrease in signal intensity was slower and the expansion of the signal distribution was less pronounced. Immunofluorescence analysis revealed a significant temporal increase in the proportion of macrophages with nanoprobe-labeled cells following transplantation. The stability and cell-penetrating ability of the nanoprobe enables the labeling of immune cell niches in RPE transplantation. Additionally, scRNA-seq analysis of nanoprobe-labeled cells identified MDK and ANXA1 signaling pathway in donor RPE cells as initiators of the immune rejection cascade, which were further amplified by macrophage-mediated pro-inflammatory signaling.ConclusionNear-infrared fluorescent nanoprobes represent a reliable method for in vivo tracing of donor RPE cells and long-term observation of nanoprobe distribution can be used to evaluate the degree of immune rejection. Molecular analysis of nanoprobe-labeled cells facilitates the characterization of the dynamic immune cell rejection niche and the landscape of donor-host interactions in RPE transplantation.

Krzysztof Strzecha, Grzegorz Rybak

The radio tomography imaging (RTI) method is very similar to X-ray tomography, but it operates in the radio frequency band without exposing the human body to harmful tissue-penetrating radiation. It can be used to monitor the number of people and their locations in buildings such as offices or hospitals. RTI can be useful in emergencies, rescue operations, and security breaches. The novelty of this paper includes the flexible architecture of an evaluation platform for RTI image reconstruction algorithms, as well as an automated evaluation process. The concept of the developed platform assumes the use of a distributed architecture based on microservices. Numerous advantages of the proposed architecture are pointed out. The presented approach ensures flexibility for further development work thanks to the system’s high degree of granularity and modularity.

Shan Zhou, Jiahui Li, Jun Lu et al.

The unique topology and physics of chiral superlattices make their self-assembly from nanoparticles highly sought after yet challenging in regard to (meta)materials1–3. Here we show that tetrahedral gold nanoparticles can transform from a perovskite-like, low-density phase with corner-to-corner connections into pinwheel assemblies with corner-to-edge connections and denser packing. Whereas corner-sharing assemblies are achiral, pinwheel superlattices become strongly mirror asymmetric on solid substrates as demonstrated by chirality measures. Liquid-phase transmission electron microscopy and computational models show that van der Waals and electrostatic interactions between nanoparticles control thermodynamic equilibrium. Variable corner-to-edge connections among tetrahedra enable fine-tuning of chirality. The domains of the bilayer superlattices show strong chiroptical activity as identified by photon-induced near-field electron microscopy and finite-difference time-domain simulations. The simplicity and versatility of substrate-supported chiral superlattices facilitate the manufacture of metastructured coatings with unusual optical, mechanical and electronic characteristics. Chiroptically active pinwheel assemblies on substrates are formed by tetrahedral gold nanoparticles from the effective ‘compression’ of a perovskite-like, low-density phase, thereby enabling the manufacture of metastructured coatings with special chiroptical characteristics as identified by photon-induced near-field electron microscopy and chirality measures.

BI Caixia

The research and application of risk analysis and evaluation for underground gas storage facilities are critical due to their diverse equipment, complex process flows, and numerous risk factors. In particular, corrosion failure accidents in ground process pipelines at these facilities have become increasingly common in recent years. Effective and accurate analysis of the causes of these corrosion failures is essential for ensuring the safe operation of underground gas storage facilities. This article presents a risk assessment methodology that leverages data and knowledge fusion. The process begins with a statistical analysis of the corrosion failure data from ground process pipelines in underground gas storage facilities, from which a Bayesian corrosion prediction model is developed. This model serves as the foundation for analyzing the basic events that lead to corrosion failure in these pipelines. Subsequently, a knowledge model of corrosion failure is established, and a detailed analysis of corrosion causes is conducted using the fault tree specific to corrosion failure in ground process pipelines. The importance of each basic event within the fault tree is quantified through the structural importance coefficient assigned to each event. The analysis categorizes the influencing factors of corrosion failure into four main groups. A judgment matrix is then created to determine the relative weight values of these different influencing factors. This matrix is crucial for setting the weight factors in the fuzzy comprehensive evaluation, which ultimately determines the risk level of corrosion failure in ground process pipelines at underground gas storage facilities. By applying examples of corrosion risk assessments for ground process pipelines, this study provides a scientific basis for enhancing safety management and operational practices at underground gas storage facilities.

Mohammadmahdi Negaresh, Milad Karbalaei‐Bagher, Yousef Jahani et al.

Abstract The investigation of chain branching in polypropylene (PP) holds significant importance for comprehending the impact of structural modifications on the properties of PP. The utilization of ethylene‐octene copolymer (EOC) presents a valuable opportunity to examine the influence of branching density on the ability of electron beam irradiation or a chemical agent in a PP blend. The introducing long chain branches (LCB) into PP can enhance its mechanical properties, particularly impact strength. This characteristic is of particular significance in applications where the material is subjected to mechanical stress, such as automotive components or packaging materials. Blends of PP/EOC were produced using 20 and 30 wt% of EOC and 0.5 phr trimethylolpropane trimethacrylate (TMPTMA) monomer. To evaluate the efficiency of branching in both solid and molten states, irradiated samples and samples mixed with dicumyl peroxide (DCP) were selected. The rheological properties of the molten blends in shear and extensional modes were assessed, and their morphology was examined using scanning electron microscopy. The existence of LCB in all samples was confirmed through dynamic viscoelastic measurements. It was concluded that although the irradiation promoted chain scission within the backbone, which resulted in long chain branching, DCP created LCB on the backbone chains of PP through chemical reaction in the melt state. Additionally, the strain hardening constant (n) was calculated, and its value for the irradiated sample PP/EOC 80/20 was 0.19, whereas its value for this blend when employing DCP was 0.14. While the complex viscosity of irradiated blend (8764 Pa.s) was greater than that of melt state branched blend (8377 Pa.s) at 0.1 rad/s, in the higher frequencies it became smaller due to the more effective creation of long chain branches through peroxide grafting in the molten state. The results of the study verified the presence of LCB in the materials by observing longer relaxation time and strain hardening behavior. Highlights The chain branching of PP/EOC blends was investigated in both the melt state and solid state through the presence of TMPTMA monomer. The effectiveness of TMPTMA monomer in grafting was mostly notable in the molten state. The steady state viscosity of LCB‐(PP/EOC) was higher in the presence of dicumyl peroxide compared to irradiated PP/EOC. The samples containing 80 wt% of PP exhibited longer side branches compared to the sample with 70 wt% of PP according to shear and extensional rheometry. The induced side chain branches resulting from irradiation and the use of dicumyl peroxide help increase the miscibility of the polymers to a similar extent.

Yusheng Li, Fan Xu, Jing liu et al.

Meng Tang, Shiwei Ma, Jianzheng Xu et al.

Chemical looping gasification (CLG) of biomass produces high contents of syngas, which would have inhibition effect on the gasification of its biomass char. Experiments using a rice husk char as fuel and a low-cost red mud as oxygen carrier for CLG investigation were performed, and effects of temperature, concentrations of steam and H2 on gasification rate were evaluated. Meanwhile, the mathematical models coupling with reaction and diffusion were established focusing on the H2 inhibition on syngas distributions inside and surrounding a single char particle. The results indicated that H2 in the reaction atmosphere has an inhibition effect on its char conversion, and at a high temperature the inhibition effect tends to be stronger. The shrinking core model (spherical symmetry) was found to be suitable to describe the char conversion under the present conditions with the reaction kinetic parameters of E = 128.8 kJ mol−1 and A = 451.2 s−1. In the internal diffusion of a single char particle, the concentrations of CO and H2 both decrease with the increase of dimensionless radius due to the consumption of carbon. In the external diffusion of the char particle, the concentrations of CO and H2 decrease with the increase of the dimensionless radius. The accumulation of H2 inside the char particle prevents CO production, thus inhibiting char gasification.

Mengnan ZUO, Wei LIU, Qi QUAN et al.

Lactic acid bacteria are of great benefit to human life and are extremely important research objects in industrial and commercial production. High-density culture of lactic acid bacteria is an important step for its industrial application. High-density culture of lactic acid bacteria can obtain higher bacterial density with lower culture volume and shorter culture cycle, improve fermentation speed and fermentation effect, and reduce the subsequent use of starter, control equipment investment and reduce production cost in production practice. High-density culture of lactic acid bacteria is affected by factors such as production strains, medium, fermentation conditions, and fermentation modes. This paper mainly reviewed nutrient consumption mode, medium, culture condition, culture technology from high-density culture of lactic acid bacteria. Finally, the future research directions were prospected, in order to provide theoretical basis for the efficient preparation and industrial application of lactic acid bacteria starter.

Raj Kumar Arya, Anurag Kumar Tiwari

Maria Cecília Fonseca Scarpi, Ângelo Oliveira Gonçalves, Antônio Fernando de Souza et al.

ABSTRACT Despite the important role of coffee production in the economy of Espirito Santo, the second largest coffee producing state in Brazil, productivity is still below the Brazilian average. One of the factors that explain this low productivity is the presence of nematodes of the genus Meloidogyne. Contaminated seedlings are an important and efficient agent for disseminating nematodes. According to normative instruction no. 35 (IN 35), of 11/29/2012 of the Ministry of Agriculture, Livestock and Supply (MAPA), the presence of Meloidogyne spp. in a single plant among a field-lot of seedlings condemns it, and the plants that compose that lot should be destroyed. In Espirito Santo, no evaluation has been carried out in nurseries covering the entire State for phytonematode detection. Therefore, the objective of this work was to carry out a nematological survey in nurseries to guide the nurserymen in relation to fulfilling IN 35 of MAPA, in addition to guiding them regarding the phytosanitary care during the production of their seedlings. The nurseries were evaluated in 19 municipalities located in both the north and the south of Espírito Santo. There were Meloidogyne spp. in evaluated samples.

J. Sorensen

Ye Cui, Di Liu, Yang Zhang et al.

A TA1 (Ti alloy)/low alloy steel (LAS) composite plate was manufactured by explosive welding. The effects of the bonding interface microstructure on the mechanical properties and fracture behavior of the composite plate were investigated. The results show that the interface has a wavy structure with intermetallic compounds (IMCs) enclosed by a steel matrix. The metallurgical bonding interface was achieved by local diffusion, with a several micrometer-thick diffusion layer. Two kinds of microcracks were formed in the IMC region and the diffusion interface. Microcracks in the IMC region propagate with difficulty due to the impediment of the IMC/steel interface. The microcracks initiated at the interface need to propagate into the fine-grain steel matrix before crack connection and delamination. The shear strength of the TA1/LAS composite plate was over 350 MPa. The composite plate could be bent up to the equipment limit (135 degrees). Excellent mechanical properties were obtained since the crack propagation was hindered by the refined or elongated steel grains induced during explosive welding.

I. Baxendale

Christelle Morin, A. Loppinet-Serani, F. Cansell et al.

A. Weber, E. Ivers-Tiffée

Xinxiao Sun, Xiaolin Shen, Rachit Jain et al.

Metabolic engineering is a powerful tool for the sustainable production of chemicals. Over the years, the exploration of microbial, animal and plant metabolism has generated a wealth of valuable genetic information. The prudent application of this knowledge on cellular metabolism and biochemistry has enabled the construction of novel metabolic pathways that do not exist in nature or enhance existing ones. The hand in hand development of computational technology, protein science and genetic manipulation tools has formed the basis of powerful emerging technologies that make the production of green chemicals and fuels a reality. Microbial production of chemicals is more feasible compared to plant and animal systems, due to simpler genetic make-up and amenable growth rates. Here, we summarize the recent progress in the synthesis of biofuels, value added chemicals, pharmaceuticals and nutraceuticals via metabolic engineering of microbes.

Gianni Pasolini, Chiara Buratti, Luca Feltrin et al.

Information and Communication Technologies (ICTs), through wireless communications and the Internet of Things (IoT) paradigm, are the enabling keys for transforming traditional cities into smart cities, since they provide the core infrastructure behind public utilities and services. However, to be effective, IoT-based services could require different technologies and network topologies, even when addressing the same urban scenario. In this paper, we highlight this aspect and present two smart city testbeds developed in Italy. The first one concerns a smart infrastructure for public lighting and relies on a heterogeneous network using the IEEE 802.15.4 short-range communication technology, whereas the second one addresses smart-building applications and is based on the LoRa low-rate, long-range communication technology. The smart lighting scenario is discussed providing the technical details and the economic benefits of a large-scale (around 3000 light poles) flexible and modular implementation of a public lighting infrastructure, while the smart-building testbed is investigated, through measurement campaigns and simulations, assessing the coverage and the performance of the LoRa technology in a real urban scenario. Results show that a proper parameter setting is needed to cover large urban areas while maintaining the airtime sufficiently low to keep packet losses at satisfactory levels.