Materials Science Research Articles

IMPROVING THE ENERGY EFFICIENCY OF THERMOELECTRIC ENERGY CONVERTERS – REVIEW

The results of an analytical review of a large number of publications on the problem of improving the efficiency of thermoelectric generators (TEG) over the past decade are presented. An analysis of historical data on the thermodynamic justification of the efficiency of thermoelectric generators is presented. The following areas are analyzed: the problem of increasing the figure of merit Z through the creation of new material science technologies and new materials, the creation of multi-segment thermoelectric elements for a wide temperature range (300 ÷ 1200 K), the efficiency of heat supply to the TEG and cooling. The methods for calculating the thermodynamic efficiency of TEG are presented. It is shown that the efficiency of TEG is limited to ½ of the Carnot value for ZT values of 1-3. Modern materials allow the production of TEG with ZT values less than 1. However, the application of TEG has promising prospects with the increase in the intensity of heat supply and cooling processes. The main directions and trends (physical, chemical, technological) in the creation and improvement of TEG are identified. Some practical solutions presented in the literature, as well as the authors' solution for improving the thermodynamic efficiency of boiler units using TEG, are shown.

MXene: A new revolution in the world of 2-D materials

MXenes have imposed a profound effect on materials science and nanotechnology fields after their discovery in 2011. Theoretical models have predicted more than 100 potential compositions of MXene whereas laboratory-scale synthesis reflects their success of over 40 distinct structures till date. The distinctive properties of MXenes have led to their use for a diverse range of applications, such as energy storage, environmental remediation, electronics, communications, gas and liquid separation and adsorption, biomedical fields, and optoelectronics. The increased interest of researchers in MXenes has led to a wide rise in research publications, showing their growing importance in different scientific domains. In 2024, MXenes had shown wide potential in various areas, including energy storage devices, electromagnetic interference shielding, nanocomposites, and hybrid materials. However, the variations in the choice of precursors, reactor design, cost, synthesis parameters pose several challenges in ensuring the production of high-quality MXenes. The applicability of MXenes continues to broaden as its compositions are continuously accelerating. This review aims is to provide a comprehensive overview of MXene history, its properties, challenges, latest trends, and different applications to highlight its potential and gather new audiences towards this family of two-dimensional materials.

Persistent Luminescence for Night‐Time Individual Identification Based on Quantum Tunneling

AbstractNight‐time individual identification requires recognizing a specific object from a bunch of homogeneous entities through night‐vision devices. It will facilitate more effective coordinated actions in night‐time disaster rescue or enforcement actions. In this work, the near infrared (NIR) persistent luminescent materials are proposed as the technology solution, which can emit the non‐visible photons continuously for hours without the external excitation. In a magnetoplumbite‐type structure, Cr3+ ions are incorporated to realize NIR emissions. By co‐doping lanthanide ions and constitutional modulation, the afterglow signal can be clearly traced under the night‐vision device over 144 h. A series of spectral measurements are utilized to reveal the mechanism behind this prolonged afterglow duration, and quantum tunneling accounts for the carrier pumping from the deep traps. It avoids the quick exhaust of carriers stored in the shallow traps, and extends the afterglow duration. In a proof‐of‐concept demonstration, the synthesized powders are used to make a quick response pattern, which can be clearly visualized in a dark room by the night‐vision devices. This work is expected to promote the research and development of persistent luminescent materials within NIR region, and to accelerate the applications in night‐time monitoring and recognition.

O PROTAGONISMO DA ENFERMAGEM NA ASSISTÊNCIA AO PARTO HUMANIZADO: UMA REVISÃO INTEGRATIVA DA LITERATURA

The puerperal pregnancy process requires dignified and qualified care, not limited to the expulsion or extraction of the fetus. The implementation of good practices in labor and birth care is essential to guarantee the rights of the parturient. It is up to the care team to provide security in the partutive process, through evidence-based methods. The present research aims to understand the actions of the nursing team involved in the humanization of childbirth, highlighting the main determining factors for maternal satisfaction and dissatisfaction in the experience of labor. This is a systematic bibliographic survey, with a qualitative approach, of the integrative literature review type. The search for research material was carried out through electronic access to the digital databases Virtual Health Library, Latin American and Caribbean Literature in Health Sciences and Scientific Electronic Library. The inclusion criteria adopted were: national articles, available free of charge, with full texts, published between 2014 and 2024. The selection process allowed eight scientific studies to be obtained. Regarding the humanization of the parturition process associated with the direct action of nursing, it can be seen that the adoption of non-invasive practices results in maternal satisfaction and reduction of fetal impairment. It was noted that the incorporation of obstetric nurses in childbirth sectors contributed to the reduction of proscribed or invasive practices. It was concluded that humanized childbirth is closely associated with the use of good practices by professionals, which will directly impact the care for the mother-child binomial. Therefore, labor and birth care policies should be constantly reinforced, providing greater dissemination of knowledge.

Application and prospects of interface engineering in energy storage and conversion of graphdiyne‐based materials

AbstractA new carbon allotrope, graphdiyne (GDY) has great promise for future use. Much interest was piqued when it was initially prepared in 2010. GDY is made up of sp‐ and sp2‐hybridized carbon atoms. It has a one‐atom thick two‐dimensional structure and many interesting and useful qualities, such as strong chemical bonds, super‐large π structures, the ability to change from an alkyne to an alkene, and can be grown on any surface. GDY has become one of the frontier hotspots in chemistry and materials science, with original research achievements in energy conversion and storage, catalysis, intelligent information, life sciences constantly emerging and so on, showing revolutionary performance. In electrochemical cells, the electrode interface content not only accounts for a small proportion in the entire electrode system but it also plays a crucial role, affecting the efficiency, lifespan, power performance, and safety performance of the battery. In view of this, the intrinsic properties of GDY have been thoroughly analyzed, and a new GDY‐based electrochemical interface has been proposed by combining the key problems of electrochemical interfaces in electrochemical energy storage and conversion. This has led to new understanding and insights to address many critical scientific issues. In this review, the structure, characteristics, and applications of GDY in interface engineering are presented. In particular, recent advances in GDY and its aggregates in energy storage and conversion are summarized and discussed.

Catalytic Enantioselective Synthesis of Boron‐Stereogenic and Axially Chiral BODIPYs via Rhodium(II)‐Catalyzed C−H (Hetero) Arylation with Diazonaphthoquinones and Diazoindenines

AbstractThe molecular engineering of boron dipyrromethenes (BODIPYs) has garnered widespread attention due to their structural diversity enabling tailored physicochemical properties for optimal applications. However, catalytic enantioselective synthesis of structurally diverse boron‐stereogenic BODIPYs through intermolecular desymmetrization and BODIPYs with atroposelectivity remains elusive. Here, we showcase rhodium(II)‐catalyzed site‐specific C−H (hetero)arylations of prochiral BODIPYs and polysubstituted BODIPYs with diazonaphthoquinonesand diazoindenines, providing efficient pathways for the rapid assembly of versatile (hetero)arylated boron‐stereogenic and axially chiral BODIPYs through long‐range desymmetrization and axial rotational restriction modes. The synthetic application of the procedures has been emphasized by the efficient synthesis of BODIPY derivatives with various functions. Photophysical properties, bioimaging, and lipid droplet‐specific targeting capability of tailored BODIPYs are also demonstrated, indicating their promising applications in biomedical research, medicinal chemistry, and material science.

Environmental Management Practices and Sustainable Green Concrete Use in Malaysia's Construction Industry: Challenges, Benefits, and Future Directions

This review examines the environmental management practices (EMPs) employed within Malaysia's construction sector, with a particular focus on sustainable practices and the adoption of green concrete, including fly ash, rice husk ash, and palm oil fuel ash varieties. The study identifies key challenges, such as low awareness, high costs, weak legal enforcement, and the underdevelopment of green materials in the country. To address these issues, the report proposes solutions such as capacity-building programs, government incentives like tax breaks and grants, regular site inspections, and investment in research and development of green materials. The review also assesses the advantages and limitations of different green concrete types used in Malaysia. The aim of this study is to enhance sustainability efforts and reduce the environmental impact of construction activities through greater awareness, stronger regulatory support, and commitment from all stakeholders. Implementing greener concrete and EMPs is expected to not only mitigate environmental concerns but also yield long-term economic benefits for Malaysia.

Precisely Prepared Hierarchical Micelles of Polyfluorene‐block‐Polythiophene‐block‐Poly(phenyl isocyanide) via Crystallization‐Driven Self‐Assembly

AbstractThe precise preparation of hierarchical micelles is a fundamental challenge in modern materials science and chemistry. Herein, poly(di‐n‐hexylfluorene)‐block‐poly(3‐tetraethylene glycol thiophene) (poly(1m‐b‐2n)) diblock copolymers and polyfluorene‐block‐polythiophene‐block‐poly(phenyl isocyanide) triblock copolymers were synthesized using a one‐pot process via the sequential addition of corresponding monomers using a Ni(II) complex as a single catalyst for living/controlled polymerization. The crystallization‐driven self‐assembly of amphiphilic conjugated poly(1m‐b‐2n) led to the formation of nanofibers with controlled lengths and narrow dispersity. The block copolymers exhibited white, yellow, and red emissions in different self‐assembly states. By using uniform poly(1m‐b‐2n) nanofibers as seeds, introducing the polyfluorene‐block‐polythiophene‐block‐poly(phenyl isocyanide) triblock polymer as a unimer in the seed growth process, and adjusting the structure of the poly(phenyl isocyanide) block and the polarity of self‐assembly solvent, A−B−A triblock micelles, multiarm branched micelles, and raft micelles were prepared.

Probing the Interplay of Protein Self-Assembly and Covalent Bond Formation in Photo-Crosslinked Silk Fibroin Hydrogels.

Covalent crosslinking of silk fibroin via native tyrosine residues has been extensively explored; however, while these materials are very promising for biomedical, optical, soft robotics, and sensor applications, their structure and mechanical properties are unstable over time. This instability results in spontaneous silk self-assembly and stiffening over time, a process that is poorly understood. This study investigates the interplay between self-assembly and di-tyrosine bond formation in silk hydrogels photo-crosslinked using ruthenium (Ru) and sodium persulfate (SPS) with visible light. The effects of silk concentration, molecular weight, Ru/SPS concentration, and solvent conditions are examined. The Ru/SPS system enables rapid crosslinking, achieving gelation within seconds and incorporating over 90% of silk into the network, even at very low protein concentrations (≥0.75%wt/v). A model emerges where silk self-assembly both before and after crosslinking affects protein phase separation, mesoscale structure, and dynamic changes in the hydrogel network over time. Silk concentration has the greatest impact on hydrogel properties, with higher silk concentration hydrogels experiencing two orders of magnitude increase in stiffness within 1 week. This new understanding and ability to tune hydrogel properties and dynamic stiffening aids in developing advanced materials for 4D biofabrication, sensing, 3D cancer models, drug delivery, and soft robotics.

Cu‐Catalyzed Oxidative Tandem Coupling and Cyclization of 2‐Aminonaphthalenes to Synthesize Dibenzo[c, g]carbazoles

AbstractA Cu(II) complex with a bipyridyl ligand bearing a Brønsted acid was used to catalyze the tandem oxidative coupling and cyclization of 2‐aminonaphthalenes to give N‐substituted‐dibenzo[c,g]carbazoles. The incorporation of an appended acidic moiety to the ligand was found to be key to the selective formation of dibenzocarbazoles over 2,2’‐diamino‐1,1’‐binaphthalene (BINAM), which is known as an irreversible byproduct. This highly efficient method yields a wide array of dibenzo[c,g]carbazoles featuring diverse functional groups as well as electronic properties. The selected dibenzo[c,g]carbazoles exhibited high photoluminescence quantum yields of up to 100 % and are promising chromophores for advanced materials.

Synthesis Framework for Designing PtPdCoNiMn High-Entropy Alloy: A Stable Electrocatalyst for Enhanced Alkaline Hydrogen Evolution Reaction.

High entropy alloys (HEAs) are an emerging class of advanced materials characterized by their multifunctionality and potential to replace commercial catalysts in electrocatalytic water splitting. The synergy among the various alloyed elements in HEAs makes them particularly promising for applications in electrocatalysis. However, preparation of HEA via bottom-up approaches by avoiding the formation of mono, di, and tri metallic alloys in the nanoscale is challenging. This aspect is addressed, in this study by exploring the logical selection of solvents, reducing agents, and capping agents, along with their relative fractions, in the solvothermal synthesis of the HEA comprising platinum-palladium-cobalt-nickel-manganese (PtPdCoNiMn). It is established that the reducing capabilities of both the solvent and reducing agent are crucial for the reduction of each metal to form a single-phase HEA. The synthesized HEA (20 wt.%)/functionalized carbon (FC) demonstrates excellent performance as an HER catalyst, exhibiting a low overpotential of 48.7mV at -10 mA cm-2 in an alkaline electrolyte. This performance is characterized by high reaction kinetics and stability at elevated current densities. Furthermore, the catalyst shows impressive performance in both simulated and actual seawater. This development reduces the reliance on platinum while enhancing the long-term durability and catalytic efficiency of the electrocatalyst.

Advances in Green Synthesis of Silver Nanoparticles: Sustainable Approaches and Applications

In the rapidly evolving field of nanotechnology, the synthesis of silver nanoparticles (AgNPs) has shifted towards eco-friendly methodologies, aligning with the growing demand for sustainable practices. Biologically synthesized AgNPs, particularly noteworthy for their applications in medicine and materials science, exhibit exceptional efficacy against microorganisms. The unique physicochemical properties of AgNPs, including their small size and large surface area-to-volume ratio, contribute to their versatility in diverse sectors. The advantages of AgNPs, such as ease of production, low cost, and high carrier capacity, make them preferred for various applications, including drug delivery systems. Despite concerns about environmental hazards and toxicity, the benefits of AgNPs, such as controlled drug release and targeted delivery, position them as valuable contributors to advancements in nanotechnology. Green synthesis methods, emphasizing biological processes and natural compounds, gain prominence for their sustainability and reduced environmental impact. The regulatory oversight of nanoproducts ensures their safe use, balancing their advantages with environmental considerations. Ongoing research promises further innovations, solidifying AgNPs' role as key contributors to progress in nanotechnology and materials science. Keywords: Silver nanoparticles, Green synthesis, Sustainable approaches, Characterization, Applications, Eco-friendly methods.

Synthesis of fluorinated acid-functionalized, electron-rich nickel porphyrins

In this study, novel fluorinated carboxylic acid esters of the generic structure TfO–CH2–(CF2)n–COOCH3 (n = 2,4,6, Tf = triflate) were synthesized. The triflates were reacted with 2-hydroxy-3,4,5-trimethoxybenzaldehyde via Williamson ether syntheses. The resulting electron-rich compounds were used as aldehydes in the Rothemund reaction with pyrrole to form ester-substituted porphyrins. After metalation with Ni(acac)2 and hydrolysis electron-rich porphyrins were obtained, that are equipped with covalently attached long chain acid substituents. The target compounds have potential applications in catalysis, sensing, and materials science. The fluorinated aliphatic carboxylic acids (TfO–CH2–(CF2)n–COOCH3) with triflate as leaving group in terminal position are easily accessible and versatile building blocks for attaching long chain acids (pKa 0–1) to substrates in Williamson ether-type reactions.

Interfacing Complex Coacervates with Natural Cells

Coacervates have been investigated as protocells or synthetic cells, as well as subcellular compartments for the creation of new materials, thus bridging the gap between living and non‐living systems in materials science, synthetic biology, and bioengineering. Given the design flexibility and simplicity of coacervates, along with the functionality and complexity of natural cells, the interfacing of complex coacervates with natural cells is considered significant for various biotechnological and biomedical applications. In this review, the fundamental mechanisms and underlying theories of coacervate systems are introduced. Recent efforts to interface coacervates with natural cells are summarized in three key scenarios: (i) the integration of coacervates with natural cell components for the living material assembly into protocells; (ii) communication between therapeutic synthetic cells and natural cells for drug delivery and cell repair; and (iii) the formation of intracellular condensates for metabolic regulation, followed by the regulation of their phase transitions for pathological elucidation. Finally, the potential of coacervate‐natural cell interfaces is discussed in the context of developing living/synthetic cell constructs, creating precise disease therapy strategies, and advancing programmable metabolic engineering networks.

Optoelectronic performance prediction of HgCdTe homojunction photodetector in long wave infrared spectral region using traditional simulations and machine learning models.

This research explores the design of an infrared (IR) photodetector using mercury cadmium telluride (Hg1-xCdxTe). It proposes two- and three-dimensional homojunction models based on p+-Hg0.7783Cd0.2217Te/n--Hg0.7783Cd0.2217Te, focusing on applications in the long-wavelength infrared range. The photodetector's performance is analyzed using Silvaco ATLAS TCAD software and compared with analytical calculations based on drift-diffusion, tunneling, and Chu's approximation techniques. Optimized for operation at 10.6μm wavelength under liquid nitrogen temperature, the proposed photodetector demonstrates promising optoelectronic characteristics including the dark current density of 0.20mA/cm2, photocurrent density of 4.98A/cm2, and photocurrent density-to-dark current density ratio of 2.46 × 104, a 3-dB cut-off frequency of 104GHz, a rise time of 0.8 ps, quantum efficiency of 58.30%, peak photocurrent responsivity of 4.98A/W, specific detectivity of 3.96 × 1011cmHz1/2/W, and noise equivalent power of 2.52 × 10-16W/Hz1/2 indicating its potential for low-noise, high-frequency and fast-switching applications. The study also incorporates machine learning regression models to validate simulation results and provide a predictive framework for performance optimization, evaluating these models using various statistical metrics. This comprehensive approach demonstrates the synergy between advanced materials science and computational techniques in developing next-generation optoelectronic devices. By combining theoretical modeling, simulation, and machine learning, the research highlights the potential to accelerate progress in IR detection technology and enhance device performance and efficiency. This multidisciplinary methodology could serve as a model for future studies in optoelectronics, illustrating how advanced materials and computational methods can be utilized to enhance device capabilities.

A compact X-ray source via fast microparticle streams.

The spatiotemporal resolution of diagnostic X-ray images is limited by the erosion and rupture of conventional stationary and rotating anodes of X-ray tubes from extreme density of input power and thermal cycling of the anode material. Conversely, detector technology has developed rapidly. Finer detector pixels demand improved output from brilliant keV-type X-ray sources with smaller X-ray focal spots than today and would be available to improve the efficacy of medical imaging. In addition, novel cancer therapy demands for greatly improved output from X-ray sources. However, since its advent in 1929, the technology of high-output compact X-ray tubes has relied upon focused electrons hitting a spinning rigid rotating anode; a technology that, despite of substantial investment in material technology, has become the primary bottleneck of further improvement. In the current study, an alternative target concept employing a stream of fast discrete metallic microparticles that intersect with the electron beam is explored by simulations that cover the most critical uncertainties. The concept is expected to have far-reaching impact in diagnostic imaging, radiation cancer therapy and non-destructive testing. We outline technical implementations that may become the basis of future X-ray source developments based on the suggested paradigm shift.

METHODOLOGICAL APPROACH TO OPTIMIZING THE MANAGEMENT STRATEGY OF THE ASSORTMENT POLICY OF A PHARMACEUTICAL COMPANY BASED ON INVENTORY CONTROL

Abstract Aim is a methodological solution for optimizing the assortment policy management strategy of a pharmaceutical company based on inventory control. Research materials and methods. The study was conducted using the example of the pharmaceutical company Bayer and is based on the principles of positivistic philosophy and a deductive approach. The research materials include primary data from an interview with a pharmaceutical logistics manager and secondary data from prescriptions. The collected data were analyzed by calculating a number of values ​​(economic order volume, reorder point, safety stock, average assortment level) using ABC analysis and cycle counting methods. According to the collected initial information, the assortment portfolio of the analyzed company includes 400 pharmaceutical products. The proposed methodological approach is based on a consistent assessment of the assortment management system in effect in the pharmaceutical company. A qualitative assessment of the assortment status is given for individual items: was it insufficient, excessive, acceptable, or discontinued. Finally, an assortment management strategy was recommended aimed at increasing the efficiency of the assortment policy while minimizing overall costs. The accuracy of the product range accounting process is improved by using the cyclic counting method and ABC classification for each product. Results. The article presents the author's methodological approach to optimizing the product range portfolio of a pharmaceutical company. The proposed approach is based on data on inventory control under conditions of uncertain demand for pharmaceutical products using a continuous analysis policy. A quantitative and qualitative assessment of the product range status for individual drug names was conducted and an adapted product range management strategy was recommended, aimed at improving the efficiency of the product range policy while minimizing overall costs. Conclusion. The accuracy of the product range dynamics accounting process is improved by using the cyclic counting method and ABC analysis of products.

Strain-engineered stretchable substrates for free-form display applications

With the growing potential of the Internet of Things, displays are being utilized to provide various types of information in every aspect of daily life, leading to the expansion of form-factor-free displays. Stretchable displays are considered the ultimate goal in form factor innovation, and they are not limited to rectangular shapes with deformation characteristics suited to target applications. Because reliable stretchable displays should be robust under uniaxial and biaxial strain, there have been efforts to tailor mechanical stress with promising strategies from structural and material perspectives. This review focuses on strain-engineering stretchable substrates for free-form display applications. First, we introduce deformable substrates with structural stretchability, achieved by incorporating buckling and Kirigami structures into plastic films, and we systematically analyze the tensile deformation characteristics based on design elements. In addition, we examined intrinsically stretchable elastomeric substrates, which have gained considerable attention due to recent advances in material and processing technologies. Their spatial modulus patterning is studied by applying optimized design principles, achieved through network alignment and crosslinking control in homogeneous elastomers, as well as by incorporating heterogeneous structures within the elastomer materials. Finally, we discussed state-of-the-art stretchable display applications employing strain-engineered stretchable substrates, focusing on advantageous materials and structures based on the display components, processes, and target deformation characteristics. Building on this foundation, we discuss the development of next-generation free-form displays and aim to contribute to their application in various static and dynamic deformation environments.

Description of Risk Factors Affecting Neonatal Jaundice

Background: Bilirubin is a chemical compound that is a product of catabolism by biliverdin reductase. Bilirubin is a yellow pigment compound. Increased bilirubin levels in babies' blood will cause neonatal jaundice and changes in skin and sclera color in babies. This study aims to determine the risk factors that influence neonatal jaundice Methods: This research used correlational analytical observational research with a cross-sectional design, using medical records of birth and jaundice babies at Gatot Subroto Army Hospital, Hermina Depok Hospital, and Hermina Kemayoran Hospital in the period January 2023 - June 2023. The total sample was 300 samples. The research instruments and materials used in this study were medical records of babies experiencing jaundice at Gatot Subroto Army Hospital, Hermina Depok Hospital, and Hermina Kemayoran Hospital. Results: Based on data analysis of several factors that have the potential to have a relationship with Neonatal Jaundice, namely: gender, type of delivery, birth weight, consumption of breast milk/formula milk, and gestational age, the results of data analysis were obtained using chi-square where for the gender factor the value was obtained. p_value 0.000 < 0.005, meaning that there is a significant relationship between gender and neonatal jaundice; for the type of delivery factor, the p-value was 0.188 < 0.005, meaning that there was no significant relationship between the type of delivery and the incidence of Neonatal Jaundice; For the birth weight factor, data was obtained with a p-value of 0.118 > 0.005, meaning that there was no significant relationship between birth weight and neonatal jaundice; Factors of consumption of breast milk/milk//formula milk on neonatal jaundice; Furthermore, the maternal gestational age factor has a p-value of 0.494>0.005, meaning that there is no significant relationship between the maternal gestational age factor and neonatal jaundice. Conclusions: Of the six factors studied, two factors have a significant relationship to neonatal jaundice, namely gender and consumption of breast milk/formula milk Keywords: Bilirubin, Neonatal Jaundice, Risk Factors

Hydrogel-based Soft Robotics for Surgical Machinery

Hydrogel-based soft robotics represent a transformative approach in surgical machinery, offering unparalleled adaptability, biocompatibility, and precision for minimally invasive procedures. Hydrogels, with their high water content and tunable mechanical properties, mimic soft biological tissues, making them ideal for applications in delicate surgical environments. This research explores the integration of hydrogel materials into soft robotic systems, focusing on their fabrication, actuation mechanisms, and performance in surgical applications. Key advancements include the development of stimuli-responsive hydrogels that enable precise control of movement and force, enhancing the capability to navigate complex anatomical structures. The study also examines computational models for simulating hydrogel behavior and optimizing robotic designs. While the potential benefits of hydrogel-based soft robotics in improving patient outcomes are significant, challenges remain in ensuring durability, scalability, and reliable control systems. This research aims to address these limitations by integrating advanced materials science with robotic engineering. By doing so, it contributes to the evolution of surgical technologies, paving the way for safer and more effective procedures.