Interesting Material Research Articles

Characterization and application of LDH with chitosan composites investigated by positron annihilation lifetime spectroscopy and surface texture for the adsorption of methyl orange

With a rapid increase in industrial growth around the world, the demand for an entirely novel category of nanoparticles and technologies for wastewater treatment has become a key concern for environmental protection. Recently, hybrids of layered double hydroxides (LDH), particularly those containing LDH, have gained attention as potential nanoscale adsorbents for water treatment. Recent research has shown that LDH-containing composites are interesting versatile materials with the ability to be used in energy storage, photocatalysis, nanocomposites, and water treatment. In the current work, LDH-containing composites were utilized as adsorbents for the purpose of purifying water. The adsorbents investigated are Zn–Co–Fe/LDH/Chitosan-in situ sample preparation (LDH/CS1) and Zn–Co–Fe/LDH/Chitosan-ex situ sample preparation (LDH/CS2). Furthermore, LDH/CS1 and LDH/CS2 were investigated for wastewater treatment from methyl orange dye (MO) with various adsorption conditions. When the initial MO concentration was 20 mg/L and the amount of adsorbent was 0.1 g, the removal efficiency reached 72.8 and 91.7% for LDH/CS1 and LDH/CS2, respectively. The MO’s maximum adsorption capabilities are 160.78 and 165.89 mg/g for LDH/CS1 and LDH/CS2, respectively, which is much greater than that of comparable commercial adsorbents. MO adsorption onto LDH/CS1 and LDH/CS2 was best characterized by the pseudo-second-order kinetic model. The equilibrium adsorption data was followed by the Freundlich and Langmuir models. The adsorption is favorable as evidenced by the equilibrium parameter RL values for MO adsorption onto LDH/CS1 and LDH/CS2, which were 0.227 and 0.144, respectively. Using the free volume distribution method and the positron annihilation lifetime technique, the nanostructure of the materials was examined.

Electrochemical detection of atrial natriuretic peptide-coated nanocarriers based on a molecularly imprinted polymer receptor thin film

Molecularly imprinted polymers (MIPs) are biomimetic materials of great interest in the scientific and industrial fields for the development of innovative sensing strategies. Herein, we proposed a new sensing application by developing an electrochemical sensor using molecular imprinting (MI) technology for recognition of atrial natriuretic peptide (ANP) both as a free molecule in solution and attached to nanoparticle-based drug delivery systems (DDSs), aiming to provide fast and reliable information on the cell uptake of nanoparticles (NPs). As proof of concept, poly(lactic-co-glycolic acid) (PLGA) NPs were synthesized and used as nanocarriers for ischemic heart disease therapy were synthesized and then functionalized with ANP (named here as PLGA-NPs@ANP). The MIP receptor film was prepared by electrochemical polymerization of dopamine over the working area of a gold screen-printed electrode (AuSPE), using cyclic voltammetry (CV) technique. The construction of the ANP sensor was carefully optimized to enhance its performance, including the film thickness and the procedures for effective template extraction from the MIP matrix. The MIP biosensor presented a linear response against polymeric NPs (PLGA-NPs@ANP) concentration logarithm ranging from 4.0 μg mL-1 to 100 μg mL-1, with a sensitivity of – 0.0129 mA mL μg-1 decade-1 and an LOD < 4.0 μg mL-1. Furthermore, the developed MIP receptor film was able to discriminate ANP-functionalized nanocarriers from non-functionalized NPs.

Analysis of Maillard reaction precursors and secondary metabolites in Chilean potatoes and neoformed contaminants during frying

Southern Chile native potatoes are an interesting raw material to produce novel snacks like colored potato chips. These novel products should be comprehensively evaluated for the presence of undesirable compounds such as acrylamide, 5-hydroxymethylfurfural and furan, the main neoformed contaminants in starchy rich fried foods. This study evaluated the neoformed contaminant levels and oil content on chips made from eleven Chilean potato accessions and compared them with commercial samples. The neoformed contaminant contents were related to Maillard reaction precursor levels (reducing sugars and asparagine) and secondary metabolites (phenolic compounds and carotenoids). Neoformed contaminants correlated well among them and were weakly correlated with reducing sugars and asparagine. Acrylamide level in native potato chips ranged from 738.2 to 1998.6 μg kg−1 while from 592.6 to 2390.5 μg kg−1 in commercial samples. Thus, there is need to implement neoformed contaminant mitigation strategies at different steps of the production chain of colored potato chips.

Pelatihan Canva untuk Siswa SMP sebagai Media Pembuatan Materi Presentasi

This training aims to improve Mardhiyah Middle School students' skills in using Canva as a tool to create interesting and informative presentation material. Canva was chosen because of its easy-to-use interface and various graphic design features that can be accessed online. The Service Team carries out training methods including an introduction to basic Canva features, such as using templates, manipulating text, setting layouts, and integrating graphic elements. In addition, this training will focus on developing students' creativity in designing presentations that are aesthetic and easy to understand, taking into account the principles of effective design. The training material also covers color management strategies, information hierarchy, and techniques for arranging content that suits the target audience. It is hoped that after attending this training, students will be more confident in creating quality presentations, using modern technology to express their ideas and information in a visual and professional way. It is hoped that this can also prepare them to face the demands of competence in the current digital era.

Meningkatkan Kopetensi Guru Bahasa Indonesia Melalui Program Pengembangan Profesional

This study examines the effectiveness of professional development programs for Indonesian language teachers at SMA 2 and SMA 9 Sijunjung in improving their teaching competence. The focus of the research includes analysis of improving teaching competence, student involvement, and creativity in teaching after participating in the program. The research method used included observation and interviews with the five teachers involved. The results of the study show that professional development programs have a significant positive impact. Teachers have experienced an increase in the application of innovative teaching methodologies and the use of educational technology. Student involvement in the learning process also increases, characterized by active participation in class discussions and assignments. The use of digital media such as learning videos and podcasts helps increase teachers' creativity in delivering more interesting and relevant material. In conclusion, professional development programs play an important role in supporting the improvement of the quality of Indonesian education, with positive implications for developing students' potential and preparing them for an increasingly complex future..

Bioethanol production from coconut husk using DES-NADES pretreatment and enzymatic hydrolysis method

Bioethanol is an alternative fuel produced during biomass fermentation. Among the available biomass resources for bioethanol production, coconut husk is an interesting raw material due to its high cellulose content. This study aims to evaluate the coconut husk conversion into bioethanol using DES (ChCl:MEA) and NADES (Be:La) solvents for the delignification process. The molar ratios of HBA and HBD of the two solvents were varied (1:4, 1:6, 1:8) at 2, 4, 6, and 8 h for each ratio. The delignified samples were hydrolyzed using the 5% (w/w) of cellulase enzymes and fermented for seven days using Saccharomyces cerevisiae. The results showed that DES (ChCl:MEA) and NADES (Be:La) could remove lignin at about 60.53% and 65.81%. The glucose content was obtained at 0.5% (brix) by both solvents and bioethanol content was obtained at 13.9% and 14% (v/v) for DES and NADES, respectively.

Elaboration and Characterization of Novel Kombucha Drinks Based on Truffles (Tuber melanosporum and Tuber aestivum) with Interesting Aromatic and Compositional Profiles.

The organoleptic and bioactive properties of truffles place these fungi as interesting materials for use in the of design functional foods based on fruiting bodies outside commercial standards. Moreover, kombucha beverages have become more popular in the Western world, leading to novel drinks using alternative substrates instead of tea leaves. In this work, two truffle species (Tuber melanosporum, TMEL; Tuber aestivum, TAES) and three different symbiotic consortia of bacteria and yeasts (SCOBYs: SC1, SC2, and SC3) were tested. Fermentation (21 days) was monitored in terms of physicochemical (pH, viscosity), biochemical (total carbohydrates, alcohol, soluble proteins, phenolic compounds), and sensory attributes (volatile organic compounds, VOCs). The obtained pH ranges were adequate, alcohol levels were undetectable or very low, and sugar content was lower than in traditional kombuchas or other beverages. In most cases, the usual bottling time could be applied (7-10 days), although longer fermentations are recommended (14 days) to reach higher protein and phenolic compounds contents. Truffle kombuchas produced up to 51 volatile organic compounds (alcohols, acids, esters, ketones, and aldehydes, among others), with TMEL showing a more complex profile than TAES. During the first week, acidic compound production was observed, especially acetic acid. Similar behavior in the VOC profile was reported with different SCOBYs.

Groups IV, V and VI metal oxide-containing hydrotalcite catalysts: state of the art on their catalytic applications

The present contribution is a review paper that summarizes the structure, properties and catalytic applications of hydrotalcite based materials when they are modified by the incorporation of oxide metals from groups 4, 5 and 6. The unique properties of hydrotalcites, with a double layer structure able to host ions in the interlayer space and its basicity, together with the properties of transitions metal oxides from groups 4, 5 and 6, leads to materials highly promising as catalysts. The incorporation can form dispersed species of those oxides on the hydrotalcite-like structure, which acts as support, or by the incorporation of those elements into the hydrotalcite structure. The structure and properties of these materials have been reviewed and analyzed, in order to give a detailed description of the main factors that affect the catalytic properties of these interesting materials.

A bacteriocin-based coating strategy to prevent vancomycin-resistant Enterococcus faecium biofilm formation on materials of interest for indwelling medical devices

The ever-increasing use of exogenous materials as indwelling medical devices in modern medicine offers to pathogens new ways to gain access to human body and begin, in some cases, life threatening infections. Biofouling of such materials with bacteria or fungi is a major concern during surgeries, since this is often associated with biofilm formation and difficult to treat, recalcitrant infections. Intense research efforts have therefore developed several strategies to shield the medical devices' surface from colonization by pathogenic microorganisms. Here, we used dopamine as a coupling agent to coat four different materials of medical interest (plastic polyetheretherketone (PEEK), stainless steel, titanium and silicone catheter) with the bacteriocins, enterocin EJ97-short and the thiopeptide micrococcin P1. Water contact angle measurements and x-ray photoelectron spectroscopy were used to verify the effective coating of the materials. The effect of bacteriocins coated on these materials on the biofilm formation by a vancomycin resistant Enterococcus faecium (VRE) strain was studied by biofilm-oriented antimicrobial test (BOAT) and electron scanning microscopy. The in vitro biocompatibility of bacteriocin-modified biomaterials was tested on cultured human cells. The results demonstrated that the binding of the bacteriocins to the implant surfaces is achieved, and the two bacteriocins in combination could inhibit biofilm formation by E. faecium on all four materials. The modified implant showed no cytotoxicity to the human cells tested. Therefore, surface modification with the two bacteriocins may offer a novel and effective way to prevent biofilm formation on a wide range of implant materials.

Photoelectrochemistry hydrogen production based on aggregation induced emission active 1,1,2,2-tetrakis(4-(9H-carbazol-9-yl)phenyl)ethene polymer, Au nanoparticles and ascorbic acid

Aggregation induced emission (AIE) active molecules have emerged as a kind of unique and important functional materials of wide scientific and technical interests, but the photoelectrochemistry (PEC) of AIE-active molecules is still little understood to date. Herein, we investigate the first-time use of AIE-active molecules for PEC hydrogen production. Au nanoparticles (AuNPs) were electrodeposited on an indium tin oxide (ITO) electrode and AIE-active 1,1,2,2-tetrakis(4-(9H-carbazol-9-yl)phenyl)ethene (TCPE) was then electropolymerized to obtain a PTCPE/AuNPs/ITO photoanode (PTCPE = poly(TCPE)). Under 100 mW cm−2 AM 1.5G simulated sunlight irradiation at a bias of 0 V vs RHE in 0.5 M aqueous Na2SO4 containing 0.1 M ascorbic acid (AA), the photocurrent density of this photoanode was 1.32 mA cm−2 (0.16 mA cm−2 if simply without AA), which is notably higher than those of PTCPE/ITO (0.43 mA cm−2) and AuNPs/ITO (0.62 μA cm−2) control photoanodes. The excellent PEC performance is explained by the broadened light absorption range of PTCPE versus the monomer, the quenching of PTCPE fluorescence via the efficient electron transfer from the lowest unoccupied molecular orbital of PTCPE to AuNPs, and the consumption of the photogenerated holes on the highest occupied molecular orbital of PTCPE by AA, because all these factors can improve the separation and transfer of photogenerated charges. This work may have provided a reference for exploring new applications of AIE-active molecules and developing new PEC and photocatalysis materials.

Enhanced fluorescence emission of a single quantum dot in a porous silicon photonic crystal—plasmonic hybrid resonator

Abstract Currently, much interest is attracted to investigating the potential of hybrid systems that exhibit plasmon-induced photoluminescence (PL) enhancement of quantum emitters in terms of optoelectronics and biosensing applications. The implementation of these systems based on photonic microcavities offers benefits due to a stronger localization of the field within the resonant cavity. Porous silicon is one of interesting materials for engineering such microcavities thanks to the simplicity of its fabrication and the possibility to embed emitters from the solution into a ready-made resonator. In this theoretical study, the fluorescence enhancement of a quantum dot (QD) in a hybrid system based on a porous silicon microcavity (pSiMC) and silver nanoplatelets (AgNPs) was investigated using finite element method (FEM) numerical simulations. For this purpose, infinite arrays were simulated by using a periodic unit cell. The pSiMC was designed as two λ/4 distributed Bragg reflectors with alternating refractive indices and a cavity layer of a double thickness between them. For comparison, simulations were also performed for an AgNP and a QD in a reference monolayer with a constant refractive index without a microcavity structure. The results show QD fluorescence enhancement in the AgNP/pSiMC hybrid system, mainly due to the higher excitation rate.

Pengembangan Media Pembelajaran Herbarium Barcode pada Materi Pteridophyta

Generation Z students like things related to smartphones as well as practical and interesting teaching materials. This research aims to determine the validity value and students' responses to barcode herbarium teaching material products on pteridophyta material. Researchers use the R&amp;D method with the Borg and Gall development model, including stages: 1) research and data collection; 2) planning; 3) product development; 4) initial field trials; 5) trial revision; 6) field trials; and 7) improvement of the resulting product. The tools used for data collection were validation questionnaires and student responses. The assessment results show that the media that has been developed is very valid in the media aspect (95%) and material (90.47%), and valid in the language aspect (80%). Students gave very good responses to the herbarium barcode learning media in small-scale trials (83.97%), as well as large-scale trials (84.56%), it was concluded that the media developed was effective and received very good responses from students.

Torrefaction and pyrolysis of agrowaste-derived materials: Properties and quality of products

Huge amounts of agricultural residues or wastes represent an interesting lignocellulosic material which can be used for energy recovery by pyrolysis as an alternative to incineration. Together with the energy production, biochar (solid residue), can be with an advantage used as a soil conditioner or for other applications such as adsorbents, supporting the principles of circular economy. Here we studied the effect of torrefaction and pyrolysis temperature from 250 to 700 °C on the composition and properties of pyrolysis gas and biochar from four types of agrowaste-derived materials: sunflower harvest residues, grain harvest residues, separate from digestion, and extracted sunflower meal. The paper provides dataset on detailed composition of pyrolysis gases, indicating the differences due to different composition of the feedstock materials and describes the main parameters affecting the use of biochar as soil amendment. Torrefaction proved to be unsuitable for the production of soil amendment quality biochar and the temperature higher than 400 °C is recommended in order to produce good quality biochar while transforming most of the energy content of feedstock to primary pyrolysis products.

Attribution of Fragments of the 16th–18th Centuries’ Early Printed Books from the Vernadsky National Library of Ukraine: Informational Potential and Practical Experience

The publication describes various cases of attributing fragments of editions from the Vernadsky National Library of Ukraine. The attribution included the identification of extracts from the text, authentication of sheets used as flyleaves, and waste paper sheets. It is shown in the examples that the binding shops at the printing houses of Ostroh, Lviv, Kyiv, and Chernihiv actively used waste paper. The article describes cases when the attribution of editions assembled from fragments, the Vilnius Gospel in particular, became the reason for a scientific study and catalogue of the Gospels of 1575–1644 in the library collection. The attribution of fragments of several different editions allowed us to identify unknown printing variants, and to form the complete Gospel text. Printed engravings inserted into books also provide interesting material for further research. The practice of studying them has shown that sometimes they are previously unknown artistic monuments by famous engravers, for example, Hryhorii Levytskyi and Ivan Myhura. The usage of various methods of work, such as the study of the history of engravings, a comprehensive analysis of their state of preservation, the establishment of the history of the copies’ use, and the study of paper filigrees, prove that book engravings were also printed for independent distribution. In particular, we are referring to images of evangelists associated with the names of Petro Mstyslavets and Pamva Berinda. The study of printed inserts of engravings, illustrations, and texts into manuscript codices is an interesting and promising area of research

PENDAMPINGAN MAHASISWA PROGRAM KAMPUS MENGAJAR ANGKATAN 7 DALAM UPAYA PENINGKATAN KEMAMPUAN LITERASI DAN NUMERASI DI SDN 3 REJOTANGAN KABUPATEN TULUNGAGUNG

The Campus Teaching Batch 7 program aims to improve students' literacy and numeracy skills through student mentoring at SDN 3 Rejotangan, Tulungagung Regency. This activity examines the effectiveness of the mentoring program in overcoming the problem of low student literacy and numeracy skills. The methods used are observation, interviews, and pre- and post-assistance tests to measure changes in students' abilities. The results show that there is a significant improvement in students' literacy and numeracy skills after receiving intensive assistance from students. This program also had a positive impact on students' learning motivation, as seen from the increased participation and enthusiasm of students in learning activities. The mentoring students acted as facilitators, providing interesting and relevant materials, and using interactive and fun learning methods. In addition, the collaboration between student assistants, teachers, and parents also supports the success of this program. Student assistance in the Teaching Campus Program Batch 7 is effective in improving students' literacy and numeracy skills at SDN 3 Rejotangan. Recommendations are given to develop similar programs in other schools to improve the quality of basic education in Indonesia.

Role of Facets and Morphologies of Different Bismuth-Based Materials for CO2 Reduction to Fuels.

Carbon dioxide (CO2) emission has been a global concern over the past few decades due to the increase in the demand of energy, a major source of which is fossil fuels. To mitigate the emission issues, as well as to find a solution for the energy needs, an ample load of research has been carried out over the past few years in CO2 reduction by catalysis. Bismuth, being an active catalyst both photocatalytically and electrocatalytically, is an interesting material that can be formed into oxides, sulphides, oxyhalides, etc. Numerous works have been published based on bismuth-based materials as active catalysts for the reduction of CO2. However, a proper understanding of the behavior of the active facets and the dependence of morphology of the different bismuth-based catalysts is an interesting notion. In this review, various bismuth-based materials will be discussed regarding their activity and charge transfer properties, based on the active facets present in them. With regard to the available literature, a summarization, including photocatalysis, electrocatalysis as well as photoelectrocatalysis, will be detailed, considering various materials with different facets and morphologies. Product selectivity, varying on morphological difference, will also be realized photoelectrochemically.

Superconductivity from On-Chip Metallization on 2D Topological Chalcogenides

Two-dimensional (2D) transition metal dichalcogenides (TMDs) is a versatile class of quantum materials of interest to various fields including, e.g., nanoelectronics, optical devices, and topological and correlated quantum matter. Tailoring the electronic properties of TMDs is essential to their applications in many directions. Here, we report that a highly controllable and uniform on-chip 2D metallization process converts a class of atomically thin TMDs into robust superconductors, a property belonging to none of the starting materials. As examples, we demonstrate the introduction of superconductivity into a class of 2D air-sensitive topological TMDs, including monolayers of Td−WTe2, 1T′−MoTe2, and 2H−MoTe2, as well as their natural and twisted bilayers, metallized with an ultrathin layer of palladium. This class of TMDs is known to exhibit intriguing topological phases ranging from topological insulator, Weyl semimetal to fractional Chern insulator. The unique, high-quality two-dimensional metallization process is based on our recent findings of the long-distance, non-Fickian in-plane mass transport and chemistry in 2D that occur at relatively low temperatures and in devices fully encapsulated with inert insulating layers. Highly compatible with existing nanofabrication techniques for van der Waals stacks, our results offer a route to designing and engineering superconductivity and topological phases in a class of correlated 2D materials. Published by the American Physical Society 2024

E-Learning berbasis Moodle Mata Pelajaran Informatika dengan Pendekatan Project Based Learning

The ppt learning delivery method for explaining lessons is considered less interesting and sometimes boring, plus project lessons are still conventional which can only be done in class. This research aims to create e-learning media with a project-based learning (PJBL) model for informatics lessons in vocational schools at Sukoharjo student park. This type of research is development by building or creating Moodle-based learning media. The method used in this research is the R&amp;D method using the ADDIE model with only the Analysis, Design, and Implementation stages. Observations and questionnaires were used for the data collection process. The data analysis technique used is descriptive analysis in the form of percentage validity tests. The results of our findings are to produce e-learning to support students in implementing the PJBL learning approach in the classroom. Test results show that all system functionality functions well. This system makes the learning process using PJBL in the classroom more flexible and can be accessed from anywhere, increases collaboration between students virtually, and utilizes technology to present more interactive and interesting learning material.

Mussel-inspired fabrication of nonwovens using fluoride-free profiled fibers for directional water transport

Fabrics with directional water transport performance have attracted considerable attention in daily life. They are in high demand, owing to their ability to transport sweat away from the skin to improve personal comfort. However, the fabrication of such materials has still remained a critical task. This article reports a nonwoven with the directional water transport function, achieved using a synergistic combination of a microstructure and a wettability gradient. The three-step fabrication strategy involves needling bonding of Y cross-section polyamide fiber webs with two needling densities (30 and 190 needle/cm2), followed by single-sided spraying of polydopamine–silicon carbide powder–polyethyleneimine dispersion and a fluoride-free hydrophobic agent. Using fiber webs with different needling densities endows the nonwoven fabric with a differential capillary effect, enhancing the directional water transport property. The unique microstructure achieves the directional water transport property by improving permeability at lower needling densities and hindering transport through a denser needling density in the reverse direction. At the same time, the wetting gradient effect promotes water transfer from the hydrophobic surface to the hydrophilic surface. The successful preparation of these interesting directional water transport materials offers new insights into the role of fibrous materials, the needling density of nonwovens, and the development of highly comfortable moisture-wicking textiles.

Phytochemical characterization of selected agro-waste extracts as kinetic inhibitors in methane hydrates formation

In this study of gas hydrate inhibition, the bio-active components (phytochemicals) and the influence of functional moieties and chemical structures on selected bio-inhibitors' performance were investigated by advanced analytical techniques. The agro-waste materials of interest are: orange mesocarp (Citrus sinensis (L)) extract (OME), red onion skin (Allium cepa) extract (ROSE), kolanut tesla (Cola acuminata) extract (KTE), coconut coir dusk (Cocos nucifera) extract (CCDE) and peanut skin (Arachis hypogea) extract (PSE). A CO2-enhanced supercritical fluid extraction (SFE) technique was used to extract the bioactive components from their parent materials. After the extraction, advanced analytical techniques including FTIR, NMR and HP-TLC with densitometry were used to identify and isolate functional groups, structurally characterize and quantify the bioactive compounds in the extracts primarily focusing on phenolic acids, flavonoids and tannins. A Bruker 500MZ NMR spectrometer and a CAMAG-semi-automatic HP-TLC system were used for the structural characterization and quantification respectively. Based on the number of anti-oxidants and radicals scavenging characteristics of the individual extracts' polyphenolic and tannin components, the expected hydrates inhibition capacities of the bio-extracts are in the magnitude: CCDE > ROSE > PSE > OME > KTE. The extracts are readily biodegradable and non-toxic and therefore do not pose ecological threat unlike PVP with only 31.50% biodegradation rate and may result in serious ecological risks in offshore environments. Lastly, the numbers of hydroxyl (OH) and meth-oxyl (MeoH) groups are the principal factors that influence the bio-inhibitors performance with hydroxyl group number being more important than that of the meth-oxyl group.