Common Materials Research Articles

The study on the wood candidates for the impact limiter of a spent fuel cask

The nuclear fuel transportation package is meticulously designed to enclose radioactive materials, guaranteeing containment even after undergoing a free-drop impact test and considering potential accident situations to prevent radioactive leakage. The impact limiters attached to the transport cask are engineered to absorb impact energy. Wood, renowned for its strong energy absorption capacity, is often specified as the core material within impact limiters. It is crucial to accurately determine the wood material employed in the impact limiter. This study carried out crushing experiments on various common wood materials to obtain stress versus strain data for the selection of the appropriate wood material. Indicators such as density, crushing strength, and densification strain are utilized to assess the suitability of wood as the filler material of the impact limiter. Paulownia wood is chosen based on density, the appropriate energy absorption value per unit volume, and response acceleration. The dispersity of the strengths of Paulownia wood is taken into account with the weakest-link models. The finite element method is adopted to precisely design and verify the impact limiter. The arrangement of the glulam wood is designed to balance the energy absorption in hypothetical accident conditions. Finally, tests on the application of the impact limiter in the transportation cask were conducted to validate the proper design of the impact limiter. This study can offer reference and data support for the research on wood filler materials.

Facile microwave synthesis of various-shaped magnetite/ reduced graphene oxide heterostructures and their magnetization properties

Heterostructures of magnetite (Fe3O4) nanoparticles and reduced graphene oxide (RGO) sheets are very common composite materials for different applications such as catalysis, energy storage, and biomedicine. Developing methods for the facile control of the size and shape of both freestanding Fe3O4 nanoparticles and those anchored onto RGO sheets is in demand. Herein, we report on the rapid and facile microwave synthesis (MWS) of Fe3O4 nanoparticles and Fe3O4/RGO with various sizes and shapes using the oleylamine (OAm)/oleic acid (OAc) ligand pair. The solvothermal synthesis using microwave irradiation (MWI) resulted in the concurrent conversion of graphene oxide (GO) into RGO and the in-situ formation of various-shaped Fe3O4 on RGO sheets. Freestanding Fe3O4 nanoparticles of various shapes were prepared using MWS for comparison. The morphological, structural, and surface properties of the samples were studied using different characterization techniques. The magnetization properties of the prepared samples were determined using a vibrating sample magnetometer. Various-shaped standalone and RGO-supported Fe3O4 nanoparticles including nanospheres, nanocubes, and nanotriangles were synthesized via MWI at 1000 W for 20 min by changing the ratios of the iron precursor and the OAm/OAc ligand pair. Interestingly, the MWI using OAm/OAc ligand pair of a molar ratio of 3:4 resulted in the in-situ formation of large hexagonal Fe3O4/RGO. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results confirm the crystallinity and spinel structure of the prepared Fe3O4 samples and prove the concurrent conversion of GO into RGO with assemblies of Fe3O4 nanoparticles. The magnetization measurements further emphasized the role of size and shape in affecting the magnetic properties of Fe3O4 and Fe3O4/RGO heterostructures. The results identify the qualities of the prepared samples and prove the MWS as a facile one-pot method for the preparation of Fe3O4 and Fe3O4/RGO heterostructures.

Identified gap in preliminary smoke assessment on new energy storage and energy harvesting materials

This research addresses the issue of smoke generation of building energy storage and energy harvesting materials in case of fire. Despite the growing concern for fire safety, our literature review on the topic points out that it predominantly emphasizes mainly new materials and their thermal conductivity and toxicity, overlooking the important dimension of smoke-generating property. Identifying this gap, as the main reason for the current research, the study introduces a proposal to use a simplified approach for assessing the smoke-generating property of these kinds of materials. Utilizing a smoke test chamber and smoke formation coefficient calculations, the model aims to bridge this gap in fire safety evaluations and regulations. Applied to common polymer materials like rigid polyurethane foam, expanded polystyrene, and expanded polyethylene foam as case studies, the proposed approach seeks to provide a comprehensive understanding of the smoke-generating property of energy storage and energy harvesting materials, ensuring a more holistic approach to building fire safety.

Nanoparticles as Drug Delivery Vehicles for People with Cystic Fibrosis.

Cystic Fibrosis (CF) is a life-shortening, genetic disease that affects approximately 145,000 people worldwide. CF causes a dehydrated mucus layer in the lungs, leading to damaging infection and inflammation that eventually result in death. Nanoparticles (NPs), drug delivery vehicles intended for inhalation, have become a recent source of interest for treating CF and CF-related conditions, and many formulations have been created thus far. This paper is intended to provide an overview of CF and the effect it has on the lungs, the barriers in using NP drug delivery vehicles for treatment, and three common material class choices for these NP formulations: metals, polymers, and lipids. The materials to be discussed include gold, silver, and iron oxide metallic NPs; polyethylene glycol, chitosan, poly lactic-co-glycolic acid, and alginate polymeric NPs; and lipid-based NPs. The novelty of this review comes from a less specific focus on nanoparticle examples, with the focus instead being on the general theory behind material function, why or how a material might be used, and how it may be preferable to other materials used in treating CF. Finally, this paper ends with a short discussion of the two FDA-approved NPs for treatment of CF-related conditions and a recommendation for the future usage of NPs in people with Cystic Fibrosis (pwCF).

Laser Desorption of Explosives from the Surface of Different Real-World Materials Studied Using C2Cl6-Dopant-Assisted Ion Mobility Spectrometry.

A highly efficient and sensitive ion mobility spectrometry (IMS) system with laser desorption sampling was applied for rapid explosive detection using different surface materials. This portable IMS detector, powered by a battery, offers mobility and is suitable for use in the field or combat zones. The laser desorption (LD) sampling of common explosives (Trinitrotoluene-TNT; Dinitrotoluenes-DNTs; Hexogene-RDX; pentaerythritol tetranitrate-PETN; plastic explosives-Compound 4 (C-4) and Semtex) on a wide range of common surface materials, such as metal, ceramic, plastic, glass, drywall, paper, wood, and textiles, was studied. Successful detection was achieved on nearly all surfaces except flammable materials (paper, wood, and textiles). The limit of detection (LOD) was determined for each explosive and specific surface, demonstrating an impressive LOD of 7 ng/mm2 for TNT. RDX, C-4, PETN, and Semtex achieved LOD values of 15 ng/mm2, while DNTs showed an LOD of approximately 50 ng/mm2.

Systematic Review of Construction Waste Management Scenarios: Informing Life Cycle Sustainability Analysis

Abstract Purpose Construction and demolition waste (CDW) is increasing due to rapid urbanization. An estimated 35% of CDW is disposed of in landfills worldwide. Thus all available strategies for minimizing the environmental and economic impacts of CDW are explored. This study reviews the use of recycled construction and demolition waste as substitutes for primary materials as well as strategies for the reuse of materials that lead to the circular economy. The aim of this study is to analyse previous literature on CDW that use life cycle analysis and contribute to the circular economy. Methodology A bibliometric analysis and systematic critical review is presented to investigate the contribution of construction materials to life cycle sustainability assessment (LCSA). The Scopus database was the main source of data reviewed. The geographical distribution, main research sources, and keywords co-occurrence were analyzed for 69 peer-reviewed articles and conference papers. Findings Most studies compared the life cycle assessment (LCA) and life cycle cost (LCC) of alternative concrete recycling methods or using waste instead of aggregates in concrete. Recycling or reuse of concrete, bricks, wood, gypsum, and steel are the most common materials studied in previous research. A knowledge gap is proposed for future research. Originality The knowledge gaps identified focus on wood waste and concrete. Currently it is not clear which of the options proposed is the most sustainable.

The role of different explosives in reducing energy and emissions in mining comminution for sustainable improvement

In the mining industry, comminution represents one of the most energy-intensive activities that generate large amounts of CO2, making it a great challenge to the industry. Using high explosives in the blasting operation can cover this comminution-related challenge. In this study, the effect of blasting on the comminution was investigated considering the mentioned challenge by blasting samples of granite rock mass using three types of common explosive materials, namely ANFO, emulite, and pentolite, at different powder factors, contrasting with other studies that focus primarily on increasing the powder factor of a specific type of explosive. Based on the results of this study, it was observed that compared to ANFO, other explosives tested in this work increased the energy consumption per ton of rock mass in the blasting stage by 1.1–1.8 times, with CO2 emission for the ANFO, emulite, and pentolite measured at 0.78 × 10−3 kg, 3.10 × 10−3 kg, and 5.14 × 10−3 kg, respectively. Also, Using ANFO, emulite, and pentolite led to 4.47 %, 6.45 %, and 7.07 % relative advantages in terms of saving total mining energy in the comminution stage. Finally, CO2 emissions for the comminution stage were estimated using Bond's indices and regional electricity data.

Preventing Dental Caries with Calcium-Based Materials: A Concise Review

This concise review provides an update on the use of calcium-based materials for the prevention of dental caries. Some calcium-based materials promote remineralization and neutralize bacterial acids, disrupting cariogenic biofilms and inhibiting bacterial growth. Medical Subject Headings of [Dental Caries] and [Calcium] were adopted to search publications. Information related to the aim of this review was extracted and summarized. Common calcium-based materials are calcium phosphate, hydroxyapatite, calcium carbonate, calcium fluoride and casein phosphopeptide–amorphous calcium phosphate (CPP-ACP). Calcium phosphate is commonly used in toothpaste. It provides calcium and phosphate ions, enhances the incorporation of fluoride into caries lesions and increases mineral density. Hydroxyapatite is a form of calcium phosphate that is chemically similar to the mineral found in teeth. It can be applied on teeth to prevent caries. Calcium carbonate can be found in toothpastes. It neutralizes bacterial acids and acts as a calcium reservoir during remineralization. Calcium fluoride is found in dental products and promotes remineralization as a source of fluoride, which can be incorporated into tooth enamel, forming fluorapatite and increasing resistance to caries. CPP-ACP is derived from milk proteins. It contains calcium and phosphate, which help to remineralize tooth enamel. CPP-ACP inhibits cariogenic bacteria. It also interacts with bacterial biofilms and disrupts their formation. These calcium-based materials can be used to boost the preventive effect of fluorides or, alternatively, as a therapy for caries prevention.

Contactless thermal diffusivity characterization of second order magnetocaloric materials under magnetic field using modulated photo-thermal radiometry method with very low power probe beam

The thermal diffusivity of magnetocaloric materials has a transition point at a given temperature that depends on the intensity of the applied magnetic field. Consequently, a fine temperature resolution on the material sample is needed to obtain an accurate determination of the thermal diffusivity variation with temperature. The coupling between the external and the internal fields has to be carefully mastered since the pertinent operating condition is fixed by the actual internal field which is not directly measurable and may be heavily affected by any element in contact with the sample. Therefore, contactless methods such as Photo-Thermal Radiometry (PTR) are privileged. The latter is based on a radiative excitation of the front face of a thin sample and the detection of the thermal effect on the opposite face. However, the powerful radiative source may significantly increase the sample temperature which is not suitable for caloric materials. In this work, a low power modulated PTR method is proposed to characterize second order magnetocaloric materials under magnetic field. It was compared to high energy thermo-flash PTR and validated on common materials such as steel and stainless steel, and then applied to gadolinium which is the reference magnetocaloric material for magnetic refrigeration and heat pumping study. The thermal diffusivity of gadolinium samples is measured in the 285.1 K to 305.1 K temperature range, including the magnetic transition temperature without and under an external magnetic flux density of 0.5 T in the 13 mm air gap of the permanent magnet magnetic circuit. The low power probe beam ensures a temperature stability with a negligible sample temperature fluctuation less than 0.05 K on the incident sample surface and less than 0.03 K on the measurement surface. The experimental results without magnetic field align with those using other methods including the magnetic transition temperatures determination. This low-power optical method proved its efficiency to characterize highly temperature dependent materials such as magnetocaloric materials sensitive to magnetic field. The data obtained partly fills the lack of information in the literature on excited gadolinium.

Digging Its Own Site: Linear Coordination Stabilizes a Pt1/Fe2O3 Single-Atom Catalyst.

Determining the local coordination of the active site is a prerequisite for the reliable modeling of single-atom catalysts (SACs). Obtaining such information is difficult on powder-based systems and much emphasis is placed on density functional theory computations based on idealized low-index surfaces of the support. In this work, we investigate how Pt atoms bind to the (11̅02) facet of α-Fe2O3; a common support material in SACs. Using a combination of scanning tunneling microscopy, X-ray photoelectron spectroscopy, and an extensive computational evolutionary search, we find that Pt atoms significantly reconfigure the support lattice to facilitate a pseudolinear coordination to surface oxygen atoms. Despite breaking three surface Fe-O bonds, this geometry is favored by 0.84 eV over the best configuration involving an unperturbed support. We suggest that the linear O-Pt-O configuration is common in reactive Pt-based SAC systems because it balances thermal stability with the ability to adsorb reactants from the gas phase. Moreover, we conclude that extensive structural searches are necessary to determine realistic active site geometries in single-atom catalysis.

Tensile testing in high-pressure gaseous hydrogen using the hollow specimen method

Metallic materials, predominantly steels, are the most common structural materials in the various components along the hydrogen supply chain. Ensuring their sustainable and safe use in hydrogen technologies is a key factor in the ramp-up of the hydrogen economy. This requires extensive materials qualification, however, most of the accepted; and standardized test methods for determining the influence of gaseous hydrogen on metallic materials describe complex and costly procedures that are only available to a very limited extent worldwide. The hollow specimen technique is a simple, rapid, and economical method designed to overcome the limitations of the current methods for the qualification of metallic materials under high-pressure hydrogen gas. However, this technique is not yet standardized. The TransHyDE-H2Hohlzug project is presented in this article, along with the main steps required to optimize the hollow specimen technique. This includes closing knowledge gaps related to the specimen geometry, surface quality, and gas purity in dedicated working packages, thus contributing to a comprehensive standardization of the technique for tests in high-pressure hydrogen gas.Impact statementThe hydrogen economy is considered a key solution for achieving climate neutrality in Europe, as it plays a crucial role in the decarbonization of sectors such as transport, industry, power, etc. Ensuring the safety and reliability of infrastructure is crucial for the ramp-up of the hydrogen economy. Therefore, it is necessary to meticulously study the materials and components used for infrastructure under conditions that closely resemble in-service conditions. The currently standardized methods are limited as they do not precisely replicate in-service conditions, and when they do, they are often complex, costly, and not easily accessible. This article presents the hollow specimen technique, a simple, and economical method developed to address the limitations of current standardized methods. The results from this work will contribute to the standardization of this technique for tests in high-pressure hydrogen gas. This will enable a faster evaluation of materials for hydrogen applications by industry and academia, thereby contributing to the growth of the hydrogen economy.Graphical abstract

A Review on the Progress of QbD Approach in Nanosystems Optimization: Current Updates and Strategic Applications

: Nanotechnology has made great strides in developing targeted drug delivery systems over the past few decades. These systems have garnered attention for their unique biological properties and ability to deliver drugs in a stable and sustainable manner. Despite these advances, there are still concerns about quality, efficacy, and safety. Many fabrication techniques still need to be refined to address the complex structures and non-standard manufacturing processes that can impact the quality of drug delivery systems. Recently, optimization techniques such as Quality by Design (QbD) have gained popularity in the pharmaceutical industry. QbD is a structured approach that addresses many technological and trait-related issues by providing a deep understanding of the product and its operations. This review examines the current state of QbD in the design of various nano-drug delivery systems, including lipid nanoparticles, lipid carriers, nano micelles, beaded drug delivery systems, nanospheres, cubosomes, and novel cosmeceuticals. Various mathematical models and statistical tests have been used to identify the parameters that influence the physical characteristics of these nanosystems. Critical process attributes such as particle size, yield, and drug entrapment have been studied to assess risk factors during development. However, critical process parameters are often identified through trial and error. This review highlights common material attributes and process parameters that affect the quality of nano-drug delivery systems. Hence, this survey has disclosed the various material attributes and process parameters, quality variables of different nano-drug systems. QbD designs such as Central drug composite, Design of experiment, D-optimal Design, Box-Benkhen Design, and Face center Design in optimizing the nanosystems have also been added. Conclusively, QbD optimization in nano drug delivery systems is expected to be a time-honored strategy in the forthcoming years.

Preparation and characterization of chitosan-rice starch films incorporating Amomum verum Blackw essential oil for grape preservation

The preservation of perishable food items presents a significant challenge in the food industry. In this study, we investigated the development and characterization of chitosan-starch films incorporated with A. verum essential oil for application in grape preservation. The films were prepared using a solvent casting method, and their physical and antibacterial properties were thoroughly evaluated. The films demonstrated tensile strength values ranging from 21.28 MPa to 27.64 MPa and elongation at break between 71.24% and 84.23%. The water vapor permeability values for chitosan-starch films were from 2.04 kg/Pa·s·m to 2.51 kg/Pa·s·m. In addition, the antibacterial activity of the films was assessed against Escherichia coli and Staphylococcus aureus. The results revealed notable inhibitory effects, with inhibition zones ranging from 14.41 mm to 21.00 mm. The films' efficacy in grape preservation was evaluated through storage experiments at room temperature for 9 days, comparing them with polypropylene film and unwrapped samples. The chitosan-starch films, particularly those containing 1.0% A. verum essential oil, exhibited superior performance in reducing weight loss and maintaining grape firmness compared to common packaging materials. Moreover, grapes covered with these current active bio-based films demonstrated higher antioxidant activity, indicating potential benefits for extending shelf life and preserving fruit quality. Chitosan-starch films incorporated with A. verum essential oil hold promise as effective and environmentally friendly packaging materials for grape preservation.

Proangiogenic potential of plasma exosomes from prostate cancer patients

Angiogenesis plays a pivotal role in the progression and metastasis of solid cancers, including prostate cancer (PCa). While small extracellular vesicles derived from PCa cell lines induce a proangiogenic phenotype in vascular endothelial cells, the contribution of plasma exosomes from patients with PCa to this process remains unclear. Here, we successfully extracted and characterized plasma exosomes. Notably, a ring of PKH67-labeled exosomes was observed around the HUVEC nucleus using fluorescence microscopy, indicating the uptake of exosomes by HUVEC. At the cellular level, PCa plasma exosomes enhanced angiogenesis, proliferation, invasion, and migration of HUVEC cells. Moreover, PCa plasma exosomes promoted angiogenesis and aortic sprouting. MicroRNAs are the most common genetic material in exosomes, and to identify miRNAs associated with the angiogenic response, we performed small RNA sequencing followed by RT-qPCR and bioinformatics analysis. These analyses revealed distinct miRNA profiles in plasma exosomes from patients with PCa compared to healthy individuals. Notably, hsa-miR-184 emerged as a potential regulator implicated in the proangiogenic effects of PCa plasma exosomes.

Quantification of Color Variation of Various Esthetic Restorative Materials in Pediatric Dentistry.

The goal of this paper is to find an association between the staining capacity of dental restorations used in pediatric patients and food items and to develop an optimum model to predict the most informative factor that causes the highest amount of color change through machine learning algorithms. Color changes in restorative materials occur as a result of intrinsic and extrinsic factors, such as the type of restorative material, food items used, polished status of the material, and time interval. This was an "in vitro study" conducted at Aligarh Muslim University, Aligarh, Uttar Pradesh, India. The study included 200 specimens, that is, 40 in each group A (orange juice), group B (Amul Kool Café), group C (Pepsi), group D (Amul Kesar Milk), and group E (artificial saliva). The materials were glass ionomer cement (GIC), resin-modified glass ionomer cement (RMGIC), microhybrid composite resin, and nanohybrid composite resin. These were further divided into polished and unpolished groups. The optimum modeling of the prediction of color change in materials by different effective factors was done by machine learning decision tree. We applied two algorithms: Chi-square automatic interaction detector (CHAID) and classification and regression tree (CART). In prediction modeling in the decision tree by CHAID and CART, color change is taken as the dependent variable, and group (type of restorative material), food items, time interval, and polished status are taken as independent variables. The various beverages caused significant color variation due to different pigmentation agents. The agent that caused the highest color change was Kool Café. The Kesar Milk had the lowest pigmentation capacity. The greatest color variation was found on Glasionomer FX-II submerged in Pepsi and the least on Ivoclar Te-Econom Plus in Kesar Milk. The mean absolute error for the training dataset in the CART model and CHAID model is 0.379 and 0.332, and for the testing data set, it is 0.398 and 0.333, respectively. Therefore, the prediction of color change by the CHAID model is optimum, and we found that the restorative materials have a maximum predictor importance of 0.86 (86%), time interval 0.07 (7%), food items 0.04 (4%), and polished status has the least importance, that is, 0.03 (3%). The staining capacity of restorative material highly depends on the material itself, the initial time interval, and least on the food items used. The clinical performance of dental restorations could be affected by various beverages consumed by children. This study thus provides important clinical insights into esthetic dentistry by offering valuable information on long-term color stability and the effect of polishing on common esthetic restorative materials used in pediatric dentistry. Varshney P, Khan SY, Jindal MK, et al. Quantification of Color Variation of Various Esthetic Restorative Materials in Pediatric Dentistry. Int J Clin Pediatr Dent 2024;17(7):754-765.

Assessing the size transformation of nanoplastics in natural water matrices

Understanding the stability of NPs in different aqueous environments, related with their size is crucial for assessing their potential risks. This is influenced by several factors, including pH, ionic strength, and the presence of biomolecules, or dissolved organic matter (DOM). In this study, dispersions of NPs derived from common plastic waste materials, including polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), and polycarbonate (PC), were synthesized by a nanoprecipitation method with sizes: 189 ± 7, 58 ± 3, 123 ± 4, 151 ± 7 and 182 ± 6 nm, respectively. Stability for a period of 14 days of these NPs was assessed in various natural water matrices. Different analytical techniques were used, including Asymmetric Flow Field-Flow Fractionation (AF4) coupled with UV–Vis and Dynamic Light Scattering (DLS) in series, batch DLS, Fourier-Transform Infrared Spectroscopy-Attenuated Total Reflection (FTIR-ATR), and Transmission Electron Microscopy (TEM). None of the studied NPs was stable in seawater and NPs were transformed in microplastics (MPs) by aggregation. PET was more prone to aggregation in all waters and PS was the most stable followed for PC, PVC and PMMA. However, bottle and tap waters maintained better the original size of NPs. For the most stable dispersion PS, the influence of heteroaggregation in tap and lagoon waters and aging from exposure to UV light in sea water were tested. In both cases, the stability over time was worse for PS. The results can contribute to a more comprehensive understanding of the fate and behaviour of NPs in natural aquatic environments, emphasizing the importance of studying a wide range of polymers.

Growth behavior of anisotropic monometallic MOFs derivatives with the high absorbing and thermal properties

The growth behavior and morphological characteristics of metal-organic frameworks (MOFs) should be considered as important factors in understanding their structure. Therefore, MOFs with atypical shapes, heterogeneous structures or abnormal properties that grow anisotropic can serve as components and templates for further directed assembly or conversion into MOF derivatives with excellent performance in electromagnetic wave absorption. Cobalt (Co) and nickel (Ni) metals have good magnetic properties and are common materials for the preparation of monometallic MOF-derived. In this study, various MOF materials with anisotropic properties, such as rod-like, flower-like, and braided, were prepared by adjusting the molar ratio of Co and Ni solvent to the organic ligand. Due to the rich inter-facial polarization and strong magnetic coupling network of the magnetic composites, Ni-MOF-b (Ni-MOF with braided shape) was prepared for the first time when the molar ratio of nickel nitrate to linker was 1:1.2. The Ni-C-b was obtained after pyrolysis of Ni-MOF-b, the minimum reflection loss of Ni-C-b was –50.7 dB at 4.0 mm. In addition, the thermal conductivity of the film prepared with Ni-C-b as filler is 2.2 W/mK. The film with integrated good heat dissipation and wave absorbing properties provides a research idea for the design of multifunctional integrated film.

Characterization of a novel phage SPX1 and biological control for biofilm of Shewanella in shrimp and food contact surfaces

Shewanella putrefaciens, commonly found in seafood, forms tenacious biofilms on various surfaces, contributing to spoilage and cross-contamination. Bacteriophages, owing to their potent lytic capabilities, have emerged as novel and safe options for preventing and eliminating contaminants across various foods and food processing environments. In this study, a novel phage SPX1 was isolated, characterized by a high burst size (43.81 ± 3.01 PFU/CFU) and a short latent period (10 min). SPX1 belongs to the Caudoviricetes class, exhibits resistance to chloroform, and sensitivity to ultraviolet. It shows stability over a wide range of temperatures (30–50 °C) and pH levels (3−11). The genome of phage SPX1 consists of 53,428 bp with 49.72 % G + C composition, and lacks tRNAs or virulence factors. Genome analysis revealed the presence of two endolysins, confirming its biofilm-removal capacity. Following the treatment of shrimp surface biofilm with the optimal MOI of 0.001 of phage SPX1 for 5 h, the bacterial count decreased by 1.84 ± 0.1 log10 CFU/cm2 (> 98.5 %). Biofilms on the surfaces of the three common materials used in shrimp processing and transportation also showed varying degrees of reduction: glass (1.98 ± 0.01 log10 CFU/cm2), stainless steel (1.93 ± 0.05 log10 CFU/cm2), and polyethylene (1.38 ± 0.1 log10 CFU/cm2). The study will contribute to phage as a novel and potent biocontrol agent for effectively managing S. putrefaciens and its biofilm, ensuring a reduction in spoilage bacteria contamination during the aquaculture, processing, and transportation of seafood products.

Energy-efficient and directional preparation of cellulose nanosheets by one-pot surface modification assisted swelling method

The energy-intensive and time-consuming process required for disassembling natural materials into nanoblocks are the major obstacles for the practical applications of biopolymer nanomaterials. Herein, a one-pot, energy-efficient and directional preparation method for gently exfoliating cellulose into nanosheets was achieved by surface modification assisted swelling process. The resulting cellulose nanosheets (CNSs) exhibited diameters ranging from 100 to 480 nm and thicknesses of approximately 5 nm, with a maximum yield of 97.9 %. This method could be widely applicable to common cellulose raw materials. Contrary to other nanocellulose reported previously, CNSs could be dried and stored in solid state, and re-dispersed in aqueous phase, thereby convenient for storage and transportation. Cellulose nanosheets films (CNSFs) obtained from CNSs showed high transparencies (>90 %) and excellent gas barrier properties, especially for the water vapor permeability of only 0.0072×10−10 cm3 cm cm−2 s−1 Pa−1, which were superior to other cellulose based films. In the simulation experiment of dry food packaging, CNSF10 possessed remarkable water vapor and oxygen blocking capabilities comparable to commercial cling films and met the practical requirements. The preparing process of CNSs reported here had the advantages including easy implementation, energy efficiency, and environmentally friendliness, and expanded possibilities for large-scale and widespread utilization of nanocellulose.

Theoretical prediction of chalcogen-based Janus monolayers for self-powered optoelectronic devices

Exploring potential two-dimensional monolayers with large photogalvanic effect (PGE) has been of great importance for developing self-powered optoelectronic devices. In this paper, we systematically investigate the generation of PGE photocurrent in chalcogen-based Janus XYZ monolayers (X/Y/Z = S, Se, Te; X ≠ Y ≠ Z) based on non-equilibrium Green's function formalism with density functional theory. The optimized Janus SSeTe, SeSTe, and TeSeS monolayers in the rectangular phase are shown stable and, respectively, possess 1.54, 1.49, and 1.74 eV indirect bandgaps. Illuminated by linearly polarized light, the PGE photocurrent without bias voltage can be collected in both armchair and zigzag directions. Unlike common Janus 2D materials with C3v symmetry, the photocurrent peak values of Janus XYZ monolayers do not come up with certain polarization angles, while the relations can be fitted by Iph = α sin(2θ) + β cos(2θ) + γ at each photon energy. Meanwhile, the maximum photoresponses of Janus SSeTe, SeSTe, and TeSeS monolayers are 2.02, 3.33, and 4.42 a20/photon, respectively. The relatively large PGE photocurrents and complicated polarization relations result from the lower symmetry of Janus XYZ monolayers. Moreover, the specific polarization angles for maximum photoresponses at each photon energy and the ratio between two transport directions are demonstrated, reflecting the anisotropy. Our results theoretically predict a potential Janus monolayer family for self-powered optoelectronic applications.