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Three different types of carbon screen-printed electrodes consisting of mesoporous carbon (MC), carbon nanofibers (CNF), and single-walled carbon nanotubes (SWCNT) were used as carbon supports for deposition of Ag, in the absence of reductant in the plating solution. The SPEs were characterized by Raman spectroscopy and show marked differences in their structure. To drive the metal deposition, the carbon supports were potentiostatically pre-treated in supporting electrolyte. The metal deposition occurred in AgNO3 solution and resulted in the formation of homogeneously distributed metal nanoparticles with type and amount depending on both the potential used in the pre-treatment step and the structure of the carbon electrodes. Larger metal amounts and higher particle densities (in the 109 cm−2 range) together with smaller particle mean sizes (in the 40- to 60-nm range) were obtained by using more negative potential for the pre-treatment. A further way to influence the characteristics of the metal deposit was based on double or triple consecutive pre-treatment/deposition cycles. The obtained results are discussed in view of the possible sources of electron supply, necessary for the formation of the metal particles on the carbon carrying substrates. [ABSTRACT FROM AUTHOR]

The incorporation of net-zero technology into preexisting energy networks is crucial for facilitating the shift toward an ecologically conscious and sustainable energy infrastructure. The primary objective of this integration is to effectively decrease carbon footprints and to provide a comprehensive understanding of the current approaches and trends related to the design and management frameworks of integrated energy networks. The initial section of this study establishes the foundation for a comprehensive examination of the particular challenges associated with decarbonization in the strategic and operational aspects of integrated energy networks. The subsequent analysis proceeds to elucidate the fundamental framework and technological architecture upon which these energy networks are constructed. This provides significant insights into the operational complexity and efficacy of the system. In addition, the paper provides a concise examination of prominent frameworks and alternative approaches that tackle the issue of low-carbon design and administration. The degree of accuracy facilitates individuals when selecting systems that align with the specific requirements of unique circumstances. Furthermore, this study provides explicit suggestions for future research based on an examination of the distinct attributes and framework of integrated energy networks. The anticipated outcome of implementing these recommendations is to enable the advancement of sustainable development and expedite the shift toward energy infrastructure with reduced carbon emissions. This will make a significant contribution to the collaborative endeavor of mitigating climate change and fostering a sustainable energy future. This study further elucidates the significant contribution of integrated energy networks in addressing climate change and enhancing energy efficiency. It achieves this by synthesizing a complete range of concepts sourced from many academic papers, industry reports, and case studies. This statement offers an examination of the multifaceted technological, legislative, and planning factors that contribute to the attainment of net-zero objectives. [ABSTRACT FROM AUTHOR]

Centralized laboratories in which analytical processes are automated to enable the analysis of large numbers of samples at relatively low cost are used for analytical testing throughout the world. However, healthcare is changing, partly due to the general recognition that care needs to be more patient-centered and putting the patient at the center of action. One way to achieve this goal is to consider point-of-care testing (PoC) devices as alternative analytical concepts. This requires miniaturization of current analytical concepts and the use of cost-effective diagnostic tools with appropriate sensitivity and specificity. Electrochemical sensors are ideally adapted as they provide robust, low-cost, and miniaturized solutions for the detection of variable analytes, yet lack the high sensitivity comparable to more classical diagnosis approaches. Advances in nanotechnology have opened up a plethora of different nanomaterials to be applied as electrode and/or sensing materials in electrochemical biosensors. The choice of materials significantly influences the sensor's sensitivity, selectivity, and overall performance. A critical review of the state of the art with respect to the development of the utilized materials (between 2019 and 2023) and where the field is heading to are the focus of this article. [ABSTRACT FROM AUTHOR]

Based on the panel data of 276 prefecture-level cities in China from 2011 to 2020, this study explores the impact of digital inclusive finance (DIF) on carbon emissions and the intrinsic mechanism of green technological innovation from a spatial perspective by constructing a spatial econometric model, a mediating effect model, and a threshold model. The results show that DIF significantly inhibits carbon emissions, exhibiting a spatial spillover effect. The transmission mechanism from a spatial perspective shows that green technological innovation plays a partial mediating role between DIF and carbon emissions, with the mediating effect accounting for approximately 59.47%. The heterogeneity analysis suggests that the impact of DIF on the reduction of carbon emissions is more pronounced in large and medium-sized cities and eastern regions. Further discussion reveals that the carbon reduction effect of DIF is also influenced by green technological innovation and industrial structure upgrading, showing threshold effects with marginal decreases and gradual increases, respectively. [ABSTRACT FROM AUTHOR]

Nanofibers are investigated to be superiorly applicable in different purposes such as drug delivery systems, air filters, wound dressing, water filters, and tissue engineering. Herein, polyacrylonitrile (PAN) is thermally treated for autocatalytic cyclization, to give optically active PAN-nanopolymer, which is subsequently applicable for preparation of nanofibers through solution blow spinning. Whereas, solution blow spinning is identified as a process for production of nanofibers characterized with high porosity and large surface area from a minimum amounts of polymer solution. The as-prepared nanofibers were shown with excellent photoluminescence and microbicide performance. According to rheological properties, to obtain spinnable PAN-nanopolymer, PAN (12.5–15% wt/vol, honey like solution, 678–834 mPa s), thermal treatment for 2–4 h must be performed, whereas, time prolongation resulted in PAN-nanopolymer gelling or rubbering. Size distribution of PAN-nanopolymer (12.5% wt/vol) is estimated (68.8 ± 22.2 nm), to reflect its compatibility for the production of carbon nanofibers with size distribution of 300–400 nm. Spectral mapping data for the photoluminescent emission showed that, PAN-nanopolymer were exhibited with two intense peaks at 498 nm and 545 nm, to affirm their superiority for production of fluorescent nanofibers. The microbial reduction % was estimated for carbon nanofibers prepared from PAN-nanopolymer (12.5% wt/vol) to be 61.5%, 71.4% and 81.9%, against S. aureus, E. coli and C. albicans, respectively. So, the prepared florescent carbon nanofibers can be potentially applicable in anti-infective therapy. [ABSTRACT FROM AUTHOR]

We developeda facile method to construct flexible, freestanding three dimensional hierarchical electrodes that consist of graphene encapsulated one-dimensional conducting polyaniline (PANi)@MnO2 coaxial nanowires grown on electrospun carbon nanofibers (denoted as G-PANi@MnO2/ECNFs). A combination of XRD, SEM, and TEM techniques were used to characterize the structures of G‑PANi@MnO2/ECNFs. Electrochemical measurements confirmed that such nanostructured composites possessed higher electrochemical capacitance than that of each individual component due to synergistic effects. The G-PANi@MnO2/ECNFs electrode exhibited extremely high specific capacitance (1364.3 F/g at 0.3 A/g) and superior cycling stability (89.2% retention rate after 2000 cycles) in a 1 M Na2SO4 aqueous solution. The excellent electrochemical performance of such nanoscale architectured electrodes provides a new route to develop flexible, freestanding, and high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

We measured thorium-234 (234Th), particulate organic carbon (POC), and chlorophyll a in the western subarctic North Pacific surface layer in 1997–2008. 234Th, POC, and chlorophyll a in the surface layer showed clear seasonal changes. As a result of approximation by using a trigonometric function, 234Th export flux estimated from the deficiency of 234Th relative to 238U and the ratio of POC to particulate 234Th (POC/234ThP) indicated constant and decreasing trends in the study area from 1997 to 2008, respectively. POC export flux estimated from 234Th decreased in the study area, showing that the strength of the biological carbon pump in this region declined in the studied decade. The ratio of POC/chlorophyll a decreased during the term. These trends were possibly caused by a decline in not the biomass but particle size of phytoplankton. Our results suggest that not only the biological carbon pump but also phytoplankton community structure change in the western subarctic Pacific Ocean in a decade. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation is a sustainable and green desalination method with great prospects for development in today's severe water shortage problem. In this paper, a novel composite aerogel was prepared by hydrothermal method with sodium alginate (SA) and Cu2+ in the preparation process using reduced graphene oxide as photothermal material and cellulose nanofibers as substrate. The good hydrophilicity of nanocellulose makes the composite aerogel have strong capillary action and continuous water transport. The gel formed by ion exchange between SA and Cu2+ greatly improves dry and wet mechanical strength of the composite aerogel and ensures the stability of the evaporator for multiple recycling. Copper is doped by reduction of copper ion complexes and reduced graphene oxide have a synergistic effect to increase the photothermal response rate of the composite aerogel of 1.446 kg m−2 h−1 with evaporation efficiency of 84.87% under one standard solar irradiation. In addition, the purification of heavy metal ions, dye wastewater as well as acid and alkali solutions also has excellent results. It is expected that this study will provide some new ideas for the fields of seawater desalination and wastewater treatment. [ABSTRACT FROM AUTHOR]

Integrating new technology in medical diagnostics presents significant potential for improving precision and productivity. To detect oral tumor cells, this study presents a unique method that uses carbon/graphene dot (CGD) and a Customized Dual Deep Neural Network (CDDNN), known as CGD-CDDNN. Given their distinct electrical and optical characteristics, graphene quantum dots (GQDs) are used as quantum dots in quantum optics to simulate the behaviour of carbon and graphene. The proposed CDDNN architecture has two routes for processing various characteristics associated with tumor cells and is specifically designed to detect oral tumors. This customized deep-learning model's goal is to recognize complex relationships and patterns in a variety of data sources. Because the network is dual, information may be processed in parallel, and complimentary aspects can be integrated more quickly. To take advantage of the unique qualities of CGDs, quantum optics concepts are incorporated into the model, offering a quantum-level comprehension of light-matter interactions in the context of oral cancer cell identification. The CGD-CDDNN system is trained on a dataset of labelled pictures of oral cancer cells using quantum-inspired embeddings and sophisticated optimisation methods. The validation of the proposed model demonstrates its effectiveness in detecting oral tumour cells, showcasing superior performance compared to conventional methods. The study emphasises the potential of quantum optics with carbon/graphene dot models and customised dual deep neural networks in revolutionising the landscape of medical imaging and tumour diagnostics. The CGD-CDDNN framework enhances accuracy and provides valuable insights into the quantum-level interactions within biological systems, paving the way for innovative applications in precision medicine. [ABSTRACT FROM AUTHOR]

An efficient and innovative electrochemiluminescence (ECL) sensor was developed for trace detection of cyfluthrin. The sensor utilized materials such as lotus root shaped carbon fiber (Co CNFs), cadmium selenide quantum dots (CdSe QDs), and Fe3O4 to amplify Ru(bpy)32+ signals. Co CNFs, with its large specific surface area and porosity, served the purpose of not only enhancing the stability of the sensor by fixing CdSe QDs and Ru(bpy)32+ on the Co CNFs/GCE, but also facilitating electron transfer. CdSe QDs was involved in the luminescence reaction and collaborated with Ru(bpy)32+ to enhance the sensor's sensitivity, while Fe3O4 promoted electron transfer in the system due to its large surface area. The solid-state ECL sensor achieved satisfactory signal under the synergistic action of these components. The ECL signal of the sensor was quenched by cyfluthrin, and a favorable linear relationship was observed between the sensor and cyfluthrin in the concentration range 1 × 10–12 to 1 × 10–6 M. The detection limit of the sensor was 3.3 × 10–13 M (S/N = 3). The utilization of lotus root shaped carbon fiber, CdSe QDs, and Fe3O4 in the Ru(bpy)32+ system demonstrated a synergistic effect for cyfluthrin detection, presenting a new approach for the rapid determination analysis of pesticide residues in foods. [ABSTRACT FROM AUTHOR]

Forest management relies on forest spatial structure, but studies on the spatial structure of Vietnamese forests are limited. Therefore, two one–hectare plots were established in tropical rainforest in Tuyen Quang province to evaluate the characteristics and spatial structures of plant communities. Descriptive statistics and species importance value indices were calculated for each plot. Then, to assess differences between plots, detrended correspondence analysis was applied. Species mingling, uniform angle, diameter dominance and carbon stock dominance indices were also computed to analyze forest spatial structures. The results indicated that 65–70% of trees occurred in areas with high diversity, and 55–58% of trees were randomly distributed. The number of dominant and non–dominant individuals, in terms of diameter and carbon stock, was similar at the stand level. In all estimated patterns, units with high species mixtures predominated. As biodiversity increased, the distribution of forest trees became more random. The quadrivariate distribution illustrated considerable differences between plots, the study area and other regions. Findings from multivariate distributions provide accurate information in each group of spatial indices and these can be used to select appropriate silvicultural measures for stand management. [ABSTRACT FROM AUTHOR]

Digital transformation and green innovation are powerful initiatives to achieve carbon peaking, carbon neutrality targets and high-quality economic development. Using a sample of high energy-consuming listed enterprises from 2012 to 2021, a double fixed-effect model is constructed to verify the effect of green innovation on the carbon emission reduction performance of high energy-consuming enterprises, and digital transformation is used as a moderating variable to analyze the inner mechanism of green innovation affecting the carbon emission reduction performance of high energy-consuming enterprises under the effect of digital transformation. The empirical results show that green innovation can significantly improve the carbon emission reduction performance of energy-consuming enterprises, while digital transformation positively moderates the effect of green innovation on the carbon emission reduction performance of energy-consuming enterprises. When considering the industry heterogeneity, the moderation effect of digital transformation is significant in the chemical raw materials and chemical products manufacturing industry and the electricity and heat production and supply industry, but the petroleum processing and coking and nuclear fuel processing industry, the non-metallic mineral products industry, the ferrous metal smelting and rolling processing industry and the non-ferrous metal smelting and rolling processing industry are not yet significantly affected by green innovation and digital transformation. The findings of the study provide empirical evidence to promote the improvement of carbon emission reduction performance of energy-intensive enterprises in China and to achieve the "double carbon" target. [ABSTRACT FROM AUTHOR]

Enhancing carbon productivity (CP) is key to achieving carbon reduction goals while maintaining economic growth. Digital technology plays a significant role in improving CP. Based on panel data from 136 countries worldwide from 2000 to 2020, this study empirically examines the impact of digitalization on CP and its mechanisms using fixed-effects and mediation models. The conclusions are as follows: (1) Overall, digitalization significantly enhances CP. (2) In terms of the mechanism, digitalization primarily improves CP through technological innovation and mitigating income inequality. (3) In terms of the quantile regression results, as the quantile level of CP increases, the promoting effect of digitalization on CP gradually strengthens. (4) From the perspective of heterogeneity among regions, income levels and human capital levels, digitalization has the greatest promotion effect on carbon productivity in European countries, high-income countries and high human capital countries. This study provides a reference for policymakers worldwide to use digital technology in achieving carbon emission reduction targets. [ABSTRACT FROM AUTHOR]

The optimal fabrication of bead-free polyvinylpyrrolidone (PVP)-based electrospun mats (EMs) with minimum average fiber diameter (~ 0.22 µm) has been carried out using the Taguchi design of experiment (DOE) approach. Hydrated metallic acetate-loaded optimized PVP-based EMs were fabricated from respective colloidal dispersions and were subsequently carbonized to fabricate metal oxide/carbon nanomaterial (MO/CNM)-based active material for electrode application. Thermal, microstructural, and morphological characterizations indicated the presence of significant interactions between metallic salts and the PVP matrix, which in turn facilitated morphology (ID/IG) specific designing of carbon nanomaterial electrodes. The MO/CNM was also subjected to Raman, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) characterization. Carbonized copper acetate-loaded PVP-based EMs (CuO/CNM) exhibited comparatively superior electrochemical performance than carbonized cobalt acetate and nickel acetate-loaded PVP-based EMs (Co3O4/CNM and NiO/CNM). Thus, the study demonstrates the optimal fabrication of metallic salt-loaded mats and the dependence of the electrochemical performance of the carbonaceous nanomaterials on their composition-specific morphological attributes, for designing engineered nanostructured materials for various functional applications such as sensors and energy storage devices. [ABSTRACT FROM AUTHOR]

The development of self-supporting electrodes, which are binder-, and additives-free, is essential for increased performance and practical applications of lithium-ion batteries (LIBs). With this aim, we report here the synthesis of carbon nanofiber (CNF) composites containing silica (SiO2) nanoparticles via Supersonic Solution Blowing (SSB) as self-supporting electrodes of LIBs. Nanofibers with average diameter in the 86–271 nm range, and specific surface area (SSA) in the 619–1981 m2/g were obtained. SiO2 content altered not only the diameter and the SSA, but also the pore-size distribution. A tri-modal pore-size distribution pattern was obtained for all specimens. Used as a self-supporting anode material for LIBs, carbon nanofiber-based composite electrodes achieved high reversible capacity, high-rate capacity, and superior cyclic stability (305–444 mAh g−1 at 0.1 A g−1 after 200 cycles), at the Coulombic efficiencies of 97−99%. Lastly, enhanced capacity can be attributed to the addition of SiO2 nanoparticles up to 2.5%. However, for higher silica content, the loss in performance can be attributed to an increase in the mean nanofiber diameter and a drastic reduction in SSA and porosity caused by the presence of nanoparticles. [ABSTRACT FROM AUTHOR]

Digital transformation and green innovation are powerful initiatives to achieve carbon peaking, carbon neutrality targets and high-quality economic development. Using a sample of high energy-consuming listed enterprises from 2012 to 2021, a double fixed-effect model is constructed to verify the effect of green innovation on the carbon emission reduction performance of high energy-consuming enterprises, and digital transformation is used as a moderating variable to analyze the inner mechanism of green innovation affecting the carbon emission reduction performance of high energy-consuming enterprises under the effect of digital transformation. The empirical results show that green innovation can significantly improve the carbon emission reduction performance of energy-consuming enterprises, while digital transformation positively moderates the effect of green innovation on the carbon emission reduction performance of energy-consuming enterprises. When considering the industry heterogeneity, the moderation effect of digital transformation is significant in the chemical raw materials and chemical products manufacturing industry and the electricity and heat production and supply industry, but the petroleum processing and coking and nuclear fuel processing industry, the non-metallic mineral products industry, the ferrous metal smelting and rolling processing industry and the non-ferrous metal smelting and rolling processing industry are not yet significantly affected by green innovation and digital transformation. The findings of the study provide empirical evidence to promote the improvement of carbon emission reduction performance of energy-intensive enterprises in China and to achieve the "double carbon" target. [ABSTRACT FROM AUTHOR]

Fischer–Tropsch Synthesis (FTS) is an important process in the production of liquid fuels in the energy sector, due to its flexibility for use with other technologies that can produce carbon monoxide (CO) and hydrogen. Catalysts have found substantial use in FTS to improve the process efficiency. However, the use of conventional FTS catalyst reduction techniques using (hydrogen (H2), CO and syngas) to activate the metal precursor has been accompanied by strong metal-support interactions. Such limitations have driven the quest for better technologies to ensure FTS catalysis reaches its full capacity. In this article, we review the activation techniques used, with emphasis on the contemporary auto-reduction technique, which has revealed energy-saving merits. Auto-reduction has the advantage of reducing the number of steps involved in catalyst preparation prior to FTS as well as eliminating costly reducing agents such as H2, CO and syngas. Auto-reduction in this article refers to the reduction of the metal precursor using a carbon support. We firstly provide a comprehensive review of the traditional reducing agents, followed by a review of the contemporary auto-reduction technique. A comparison of the conventional FTS catalyst reduction and auto-reduction techniques is provided to allow for a fundamental understanding of the merits and demerits of both techniques. The different types of nanostructured carbon materials used in aiding auto-reduction for the FTS process are reviewed. [ABSTRACT FROM AUTHOR]

Mg-ion batteries (MIBs) possess promising advantages over monovalent Li-ion battery. However, the exploitation of desirable cathode materials encounters the dilemma of sluggish reaction kinetics caused by strong coulomb interaction between Mg2+ and cathode. Reasonable electrode structure design is of great importance for achieving fast Mg2+ intercalation kinetics. Herein, a novel configuration composed of sub-5 nm amorphous V2O5 quantum dots and nitrogen-doping carbon nanofibers (a-V2O5-QDs@NCNFs) was elaborately designed and fabricated. Sub-5 nm QDs provide shorter diffusion path and more storage sites for Mg2+. Simultaneously, a large range of disorder states in amorphous structure can provide more open diffusion channels for Mg2+ transport. In addition, NCNFs play a crucial part in relieving the volumetric strains of V2O5 and maintaining the structural integrity during Mg2+ insertion/extraction. Reflecting in MIBs, a-V2O5-QDs@NCNFs deliver ultra-long cycling life (5000 cycles at 5 A g−1) and outstanding rate performance (52 mAh g−1 at 20 A g−1). This design conception opens up a new route for exploiting high-performance cathode for MIBs. [ABSTRACT FROM AUTHOR]

The rapid development of electronic information technology makes the impact of electromagnetic waves on human life more and more prominent. Through electrospinning and high-temperature carbonization processes, we composited magnetic nanoparticles and carbon fibers and successfully embedded Fe–Ni nanoparticles into nanofibers uniformly. Through the comparative study of the alloy particle concentration in the composite material, we found that the Fe0.64Ni0.36@CNF composite material with an appropriate composition exhibits excellent microwave absorption performance. When the matching thickness is 4 mm, the minimum reflection loss can reach − 34.21 dB at 8.6 GHz frequency, the maximum EAB reaches 5 GHz (11.9–16.9 GHz), and the comprehensive EAB is 10.8 GHz. Our results show that magnetic nanoparticles can regulate the electromagnetic parameters of carbon materials to a certain extent, and reasonable compounding can make them have better impedance matching and attenuation characteristics. [ABSTRACT FROM AUTHOR]

In order to study the theoretical mechanism of the impact of green technology progress on carbon emissions, this article constructs a theoretical mechanism of the impact of green technology progress on carbon emission growth. Explore the conditions for achieving carbon peak and carbon reduction. Based on the Cobb Douglas production function, construct a three sector model that includes capital, labor, and energy. Empirical methods were used to analyze the quantitative impact of green technology progress on carbon emission growth and the moderating effect of energy input share. This study mainly used provincial panel data from 1995 to 2020. Calculate carbon dioxide emissions based on energy consumption and carbon dioxide emission coefficients of various energy sources in different regions. Using the perpetual inventory method to calculate capital growth rate, green computing progress rate, etc., to provide data support for the green technology carbon reduction model. Empirical analysis of the impact of green technology progress on carbon emissions using the FGLS panel model. Theoretical and empirical analyses show that green technological progress promotes an increase in the carbon emission growth rate through the scale effect, with an impact coefficient of 0.607; it promotes a decrease in the carbon emission growth rate through the technological effect, with an impact coefficient of − 0.667; the combined effect promotes a decrease in growth rate of carbon emissions, with an impact coefficient of − 0.06. The share of energy inputs has a positive regulating effect on the scale effect. [ABSTRACT FROM AUTHOR]

Spun calcination introduces a novel approach for the development of materials suitable for optoelectronic applications, particularly carbon-based materials. In this study, we utilized the spun calcination technique to design rGO and rGO@CNF nanocomposites with the help of C20H38O11. By subjecting polymeric nanofibers to thermal reduction, we successfully achieved the formation of rGO and rGO@CNF, as confirmed by peak resolution in X-Ray diffraction analysis. The nanocomposites exhibited a crystalline phase, with average crystallite sizes of approximately 1.33 nm and 1.22 nm for rGO and rGO@CNF, respectively. The Raman spectroscopy shows intense G and D-bands observed in the spectra further supported the formation of these carbon-based materials, with IG/ID intensity ratios of approximately 0.85 and 0.87 for rGO and rGO@CNF, respectively. The photoluminescence study shows the structural growth of the nanocomposite indicated the diffusion of carbon surfaces, which revealed that both rGO and rGO@CNF shows lower electron-hole pair recombination rate. Consequently, these materials exhibited a considerable number of delocalized free electrons, leading to enhanced photoluminescence activity. [ABSTRACT FROM AUTHOR]

Sweat is easily accessible from the human skin's surface. It is secreted by the eccrine glands and contains a wealth of physiological information, including metabolites and electrolytes like glucose and Na ions. Sweat is a particularly useful biofluid because of its easy and non-invasive access, unlike other biofluids, like blood. On the other hand, nanomaterials have started to show promise operation as a competitive substitute for biosensors and molecular sensors throughout the last 10 years. Among the most synthetic nanomaterials that are studied, applied, and discussed, carbon nanomaterials are special. They are desirable candidates for sensor applications because of their many intrinsic electrical, magnetic, and optical characteristics; their chemical diversity and simplicity of manipulation; their biocompatibility; and their effectiveness as a chemically resistant platform. Carbon nanofibers (CNFs), carbon dots (CDs), carbon nanotubes (CNTs), and graphene have been intensively investigated as molecular sensors or as components that can be integrated into devices. In this review, we summarize recent advances in the use of carbon nanomaterials as sweat sensors and consider how they can be utilized to detect a diverse range of analytes in sweat, such as glucose, ions, lactate, cortisol, uric acid, and pH. [ABSTRACT FROM AUTHOR]

A novel cobalt-doped two-dimensional molybdenum diselenide/polypyrrole hybrid-based carbon nanofiber (Co/MoSe2/PPy@CNF) was prepared using the hydrothermal method followed by electrospinning technique. The structural and morphological properties of the 2D-TMD@CNF-based hybrids were characterized through X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), and transmission electron microscopy (TEM). The Co-MoSe2/PPy@CNF exhibited large surface area, porous structure, and improved active sites due to the synergistic effect of the components. The electrochemical and electrocatalytic characteristics of the 2D-TMD@CNF-modified electrodes were also investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The Co/MoSe2/PPy@CNF electrode was used as an electrochemical sensor for simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA) and showed enhanced catalytic activity and sensitivity. Using DPV measurements, the Co/MoSe2/PPy@CNF demonstrated wide linear ranges of 30–3212 μM for AA, 1.2–536 μM for DA, and 10–1071 μM for UA with low detection limits of 6.32, 0.45, and 0.81 μM, respectively. The developed sensor with the Co/MoSe2/PPy@CNF-modified electrode was also applied to a human urine sample and gave recoveries ranging from 94.0 to 105.5% (n = 3) for AA, DA, and UA. Furthermore, the Co/MoSe2/PPy@CNF-based sensor exhibited good selectivity and reproducibility for the detection of AA, DA, and UA. [ABSTRACT FROM AUTHOR]

Special features of structural and phase transformations, position of critical points, quantitative parameters of the structure, and hardness under continuous transformation of supercooled austenite in steels 30KhNMFRA, 30KhGNMFRA and 30KhN3MFRA are determined. Thermokinetic diagrams of decomposition of supercooled austenite in the steels are plotted using a Gleeble 3500 research complex. Recommendations are developed for selection of chemical composition and cooling rate for billets in order to provide a high strength and enough impact toughness of the steels after quenching and low tempering. The results may be used for development of high-strength cold-resistant steels and modes of their heat hardening. [ABSTRACT FROM AUTHOR]

In this study, simulation of a silicon sensitive element (SE) of capacitive accelerometer using the analytical model to obtain the optimized sensitivity of the capacitive type accelerometer structure with comb-drives is presented. The objective of the article is to consider the design of the silicon SE, deformation results, mechanical stresses and capacitance changes between the gaps of comb-drives on the silicon SE of MEMS-based capacitive type accelerometer. At first, the structural design of the silicon SE of MEMS-based capacitive accelerometer structure with the sensitive comb-drives using the software of SOLIDWORKS is given. The deformation results and mechanical stresses of the SE of MEMS-based capacitive accelerometer along the working axes of X and Y, which play an essential role for calculation of capacitance changes between the comb-drives of the structure by using the ANSYS software are analyzed. The deformation results of the silicon SE at the temperature ranges from –40 to 80°С with an acceleration range of 300 g by using the program of ANSYS are considered. Capacitance changes between comb-drives based on the deformation results on the silicon SE of capacitive accelerometer with the membrane of 40 µm thickness when exposed to the structure of the SE with the acceleration ranges from 50 to 300 g by using the program of Ansys Maxwell are studied. To enhance the sensitivity of the capacitive comb type accelerometer, the presented design is more appropriate for manufacturing of sensitive devices in the field of MEMS sensors. [ABSTRACT FROM AUTHOR]

Highlights: Heterogeneous interface engineering is designed by electrospinning. The introduction of Co3SnC0.7 nanoparticles increased the loss mechanism. Enhanced electromagnetic loss and improved impedance matching are achieved. The absorbers exhibit high-efficient electromagnetic wave absorption performance. Application of novel radio technologies and equipment inevitably leads to electromagnetic pollution. One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain high-performance microwave absorbers. Herein, we reported a one-dimensional N-doped carbon nanofibers material which encapsulated the hollow Co3SnC0.7 nanocubes in the fiber lumen by electrospinning. Space charge stacking formed between nanoparticles can be channeled by longitudinal fibrous structures. The dielectric constant of the fibers is highly related to the carbonization temperature, and the great impedance matching can be achieved by synergetic effect between Co3SnC0.7 and carbon network. At 800 °C, the necklace-like Co3SnC0.7/CNF with 5% low load achieves an excellent RL value of − 51.2 dB at 2.3 mm and the effective absorption bandwidth of 7.44 GHz with matching thickness of 2.5 mm. The multiple electromagnetic wave (EMW) reflections and interfacial polarization between the fibers and the fibers internal contribute a major effect to attenuating the EMW. These strategies for regulating electromagnetic performance can be expanded to other electromagnetic functional materials which facilitate the development of emerging absorbers. [ABSTRACT FROM AUTHOR]

Electrospinning is a simple and effective technique for preparing carbon nanofibers. However, carbon nanofiber materials have some drawbacks, such as low specific surface area, small pore size, and low porosity, which can affect the electrochemical performance of supercapacitors. This article proposes a preparation method for a multi-level porous structure for thick electrodes. Sponge-like nanofibers are formed through electrospinning by adding a certain amount of PMMA to the polyacrylonitrile mixed spinning solution after doping with heteroatoms. After reverse hanging pre-oxidation and carbonization, a hierarchical porous, highly conductive, and flexible carbon nanofiber sponge is obtained. After testing, at a current density of 0.25 A g−1, its specific capacitance reached 207 F g−1. As the power density increased from 250 W kg−1 to 3997.89 W kg−1, the energy density changed from 28.73 W h kg−1 to 8.44 W h kg−1, demonstrating that the porous active carbon nanofiber sponge electrode has a significant energy storage advantage. [ABSTRACT FROM AUTHOR]

Reasonable construction of high activity and low cost non-noble metal oxygen reduction reaction (ORR) catalyst is of great importance for the wide application of zinc-air batteries (ZABs). Using bimetallic MOF as a precursor combined with electrospinning, high-temperature carbonization and electrodeposition, we successfully developed a porous carbon nanofiber (Co@Fe-CNFs-1000) with bimetallic active center as an efficient catalyst for ORR. The successful construction of this special core-shell structure directly explores the synergy between different active centers. The results showed that the synthesized Co@Fe-CNFs-1000 catalyst exhibited ORR performance comparable to that of Pt/C in 0.1 mol/L KOH electrolyte, high half-wave potential (E1/2=0.81 V) and limiting current density (JL=5.4 mA-cm−2). In addition, homemade liquid ZABs with Co@Fe-CNFs-1000 as the air cathode showed excellent power density (155.8 mW·cm−2), specific capacity (780.6 mAh·gZn−1) and long-term stability (over 100 h at 2 mA·cm−2), surpassing even Pt/C-based batteries. In addition, the flexible solid-state ZABs assembled based on Co@Fe-CNFs-1000 demonstrates excellent flexibility and durability. This work provides a new idea for constructing ORR catalysts with high activity centers. [ABSTRACT FROM AUTHOR]

The developed microstructures and tensile strength of AISI 420-type martensitic stainless steels with different carbon content from 0.2 to 0.4% were studied after tempering at 450°C for 3 h and at 800°C for 16 h. The volume fraction of retained austenite depends significantly on the carbon content. The fraction of retained austenite is about 0.3 after tempering at 450°C for 3 h in steels with 0.3–0.4% carbon. An average grain size comprises 0.97 μm and 0.6 μm after tempering at 450°C for 3 h in the steels with carbon content of 0.2 and 0.4%, respectively. Tempering at 800°C for 16 h increases the grain size to 2.1 μm in the 0.2% C steel and to 1.3 μm in the 0.4% C steel. The phase transformation during high temperature tempering is accompanied by recovery and subgrain coalescence. Depending on the carbon content, a tensile strength of 1700–1900 MPa or 650–750 MPa can be achieved after tempering at 450°C or 800°C, respectively. [ABSTRACT FROM AUTHOR]

Nanocatalyst is rapidly developing field and is a key factor of environmentally-safe sustainable technology and organic transformations. An increasing interest is nowadays devoted to the high activity and selectivity of nanocatalyst. Several, attractive candidates as a catalyst are, metal nanocatalysts, metal oxide nanocatalysts, bimetallic nanocatalysts, and supported NPs, deed sustainable idea to conduct divers big chemical transformations in an environmentally friendly aspects. The fringe benefits affiliated with the catalytic applications of nanoparticles in organic synthesis completed beneath very moderate and green conditions. This review goals to present the prevailing crest on the applications of numerous kinds of nanoparticles for organic transformations. At the end, the author's viewpoints are; counting imminent advancement of green, sustainable and efficient chemical processes is one of the biggest crucial challenges in the area of organic synthetic nanotechnology via sustainable environmentally friendly manner. [ABSTRACT FROM AUTHOR]

Carbon nanofibers (CNFs) were heat-treated at 1100 °C (CNF1100) and 2500 °C (CNF2500), respectively, and embedded as fillers at different mass percentages into an epoxy mixture. The paper aims at evaluating, through a comparison between the two different types of resulting nanocomposites, the influence of the CNF heat treatment on the thermal, mechanical, and electrical performance of the formulated samples. Thermogravimetric analysis (TGA) showed oxidative stability in the air of CNF2500 approximately 200 °C higher than the CNF1100 ones. The first oxidation stage of the resins embedding the two typologies of CNFs falls between 380 and 480 °C. This means that the temperature of the heat treatment of the nanofiller does not influence the temperature at which the thermodegradation of the nanocomposites starts. Differential Scanning Calorimetry (DSC) data show that the highest degree of cure (DC) was recorded for the epoxy samples filled with CNF2500. CNF thermal treatment increases the direct current (dc) conductivity of the nanocomposite by 3 orders of magnitude around the electrical percolation threshold (EPT) and increases the storage modulus of the CNF2500-based resins up to 60 °C compared with the unfilled resin. The peculiar wall structure of CNF1100 determines a further slight enhancement. Tunneling Atomic Force Microscopy (TUNA) reveals that the CNFs are evenly distributed on the nanodomains showing higher electric current values for samples loaded with CNF2500. [ABSTRACT FROM AUTHOR]

Creating ultrathin, mountable fibers from a wide range of polymeric functional materials has made electrospinning an adequate approach to producing highly flexible and elastic materials. In this paper, electrospinning was utilized to produce thermoplastic polyurethane (TPU) nanofibrous membranes for the purpose of studying their thermal and mechanical properties. Towards a study of the effects of fiber orientation and multi-walled carbon nanotubes (MWCNTs) as a filler on both mechanical and thermal characteristics of electrospun TPU mats, an experimental comparison was held between unidirectional and randomly aligned TPU and TPU/MWCNTs nanofibrous structures. The incorporation of MWCNTs into randomly oriented TPU nanofibers resulted in a significant increase in Young's modulus (E), from 3.9 to 7.5 MPa. On the other hand, for unidirectionally spun fibers, Young's modulus increased from 17.1 to 18.4 MPa upon the addition of MWCNTs. However, dynamic mechanical analysis revealed a different behavior. The randomly oriented specimens exhibited a storage modulus with a significant increase from 180 to 614 MPa for TPU and TPU/MWCNTs mats, respectively, and a slight increase from 119 to 143 MPa for unidirectional TPU and TPU/MWCNTs mats, respectively. Meanwhile, the loss modulus increased with the addition of MWCNTs from 15.7 to 58.9 MPa and from 6.4 to 12 MPa for the random and aligned fibers, respectively. The glass transition values for all the mats fell in the temperature range of – 60 to − 20 °C. The thermal degradation of the membranes was not significantly affected by the addition of MWCNTs, indicating that the mixing of the two constituents did not change the TPU's polymer structure and that the TPU/MWCNTs nanocomposite exhibited stable thermal degradation properties. [ABSTRACT FROM AUTHOR]

A flexible wearable electrode consisting of nickel–cobalt sulfide (NCS) nanowires was fabricated in this study. Self-supporting NCS was grown in situ on porous carbon nanofibers without a binder as a novel material for supercapacitor electrodes. The NCS nanowires were grown using cyclic voltammetry electrodeposition, which proved to be a fast and environmentally friendly method with good controllability of the material structure. One-dimensional carbon nanofibers (C) have high surface-area-to-volume ratios, short ion transmission distances, excellent mechanical strengths, and remarkable flexibilities. Moreover, the NCS@C flexible electrode exhibited a synergetic effect with the active compounds, and the dense active sites were uniformly distributed across the entire surface of the carbon fibers, enabling rapid electron transport and enhancing the electrochemical properties of the NCS@C nanowires. The NCS@C achieved specific capacitances of 334.7 and 242.0 mAh g−1 at a current density of 2 A g−1 and high current densities (up to 40 A g−1), respectively, corresponding to a 72.3% retention rate. An NCS@C-nanofilm-based cathode and an activated-carbon-based anode were used to fabricate a flexible asymmetric supercapacitor. The device exhibited high energy and power densities of 12.91 Wh kg−1 and 358 W kg−1, respectively. [ABSTRACT FROM AUTHOR]

Traditionally, cellulose nanofiber (CNF) production has primarily relied on virgin cellulose sources. Yet, the shift to using paper mill sludge (PMS) as a source for CNF underscores the significance of reusing and recycling industrial byproducts. PMS contains significant amounts of cellulose that can be extracted as a raw material. The purpose of present study is to provide a sustainable approach to PMS utilization as a paper coating additive in the cellulose nanofibrils (CNFPMS) form via simply scalable wire-wound rod coating method. The effect of CNFPMS additive amounts at two coating layers on microstructure and surface properties of coatings such as porosity, air permeability surface roughness and optical properties such as brightness, gloss and CIE L*a*b* is studied, which they can also provide insight for the eventual print performance. Results indicated that the obtained CNFPMS in paper coating shows 52% decrease in porosity, presenting significant improvement in the coating microstructure. The marginal increase in permeability coefficient and surface roughness, 54% and 10%, respectively, suggests improving color reproduction and preventing color density losses. Optical analysis showed slight decrease in brightness and gloss, as was expected. Notably, the lightness was improved, which also indicates increasing color gamut volume in printing applications. As a result, the current work offers a sustainable approach to manage PMS for use in paper coatings as a high-value-added material. [ABSTRACT FROM AUTHOR]

It is of much importance to clarify the impact of technological innovation on carbon emission intensity for the low-carbon transformation of China's economy. This study, based on the panel data of 30 Chinese provinces and municipalities from 2010 to 2020, measures and analyzes the carbon emission intensity and the level of technological innovation, establishing a spatial econometric model to study the spatial spillover effect and a panel threshold model to analyze the nonlinear influence of technological innovation level on carbon emission intensity. The findings are as follows: First, the overall carbon emission intensity in China shows a decreasing trend from 2010 to 2020, with the average dropping from 3.09 in 2010 to 1.98 in 2020; Second, the spatial autocorrelation results reveal that the level of technological innovation and carbon emission intensity in China are obviously aggregated in the global spatial distribution pattern. Third, the regression results of the spatial econometric model show that the direct effect of technological innovation on carbon emission intensity is significantly negative at the level of 1%, that is, the improvement of the technological innovation in a certain area has a significant inhibitory effect on carbon emission intensity. Fourth, based on the level of economic development, there is a significant three-threshold effect of the level of technological innovation on carbon emission intensity in China, and the influence of the level of technological innovation on carbon emission intensity varies in the direction of existence and coefficient values within different threshold intervals. As economic development reaches the third interval, the technological innovation level has the most significant inhibition on carbon emission intensity. These findings enriches the research of the nonlinear relationship between technological innovation and carbon emission intensity, clarifies the spatial spillover effect and threshold effect between among them, and provides inspiration for better promote the low-carbon transformation of economy. [ABSTRACT FROM AUTHOR]

Because the requirements of environmental protection are becoming strict, the preparation of petroleum products such as white oil needs to be harmless. In order to produce high-grade white oil products, it is necessary to study the medium-pressure hydrogenation technology and the suitable high-activity hydrogenation catalyst. The medium-pressure hydrogenation technology is proposed to produce white oil by a one-stage hydrogenation process under 7-8 MPa hydrogen partial pressure. The paper optimized the optimum conditions for medium-pressure hydrogenation of white oil. The initial reaction temperature was 210°C. The reaction pressure was 8 MPa. The liquid space velocity was 0.4 h-1. The hydrogen oil ratio was 500:1 V/V. The catalyst life evaluation experiment was carried out. The research results can provide a basis for the selection of hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

A new voltammetric method is proposed for high sensitive thiethylperazine (THP) determination, using a glassy carbon electrode modified with semi-graphitized carbon nanofibers/MnO nanocomposite (eCNF/MnO/GC). To the best of our knowledge, this is the first electrochemical assay of THP determination, and the first use of the eCNF/MnO as the electrode modifier. The proposed method using eCNF/MnO/GC is characterized by high repeatability and sensitivity of measurements, with the linearity of THP in the range from 0.05 to 2.2 µmol L−1. The lowest detection limit achieved on the eCNF/MnO/GC electrode for 30 s of preconcentration was 6.3 nmol L−1 THP in 0.05 mol L−1 acetate buffer of pH 5.6. The proposed method was successfully applied to highly sensitive THP determination in complex matrices, such as tablets and plasma with good recovery (98–103%). The RSD value obtained for THP measurement at a concentration of 0.1 µmol L−1 was 1.3%. Amperometric measurements of THP under the flow injection conditions were also performed to indicate the possibility of its fast and accurate determination (103% and 95% for unmodified and modified electrode, respectively), with the duration of single analysis of approx. 30 s. [ABSTRACT FROM AUTHOR]

Of the carbon materials for capacitive deionization (CDI), carbon nanofibers prepared by electrospinning are a good alternative. A convenient method for effectively increasing the mesopore volume and modulate the micro-nano morphology of electrospun fibers still keep on developing. In this study, aiming at the requirement of CDI electrodes, a designed structure of carbon fibers embedded with porous carbon sheets was fabricated successfully. During preparation, instead of common polymer solution and its electrospinning, a triphase solution was carried out for combined electrospinning/electrospray process, which result in a self-supporting mat with high flexibility. Droplets were dispersed on newly formed fibers and solidified into porous sheets. Thus, a binary morphology of fibers and sheets was obtained. The mesopore volume of this work is 0.329 cm3 g−1, about 2.9 times larger than that of activated carbon fibers (ACF). The prepared electrodes exhibited an adsorption capacity of 15.1 mg g−1. The kinetics of electrosorption processes was also studied by Weber-Morris model. In summary, the classic ACF synthesis method was modified in the electrospinning step. An optimized morphology of the carbon mat was obtained, with no extra reagents and no material doping. This study might spark more interest for the advancement of electrospray/electrospinning methods and promote research on phase separation for CDI material preparation. [ABSTRACT FROM AUTHOR]

It is essential to predict carbon prices precisely in order to reduce CO2 emissions and mitigate global warming. As a solution to the limitations of a single machine learning model that has insufficient forecasting capability in the carbon price prediction problem, a carbon price prediction model (GWO–XGBOOST–CEEMDAN) based on the combination of grey wolf optimizer (GWO), extreme gradient boosting (XGBOOST), and complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) is put forward in this paper. First, a random forest (RF) method is employed to screen the primary carbon price indicators and determine the main influencing factors. Second, the GWO–XGBOOST model is established, and the GWO algorithm is utilized to optimize the XGBOOST model parameters. Finally, the residual series of the GWO–XGBOOST model are decomposed and corrected using the CEEMDAN method to produce the GWO–XGBOOST–CEEMDAN model. Three carbon emission trading markets, Guangdong, Hubei, and Fujian, were experimentally predicted to verify the model's validity. Based on the experimental results, it has been demonstrated that the proposed hybrid model has enhanced prediction precision compared to the comparison model, providing an effective experimental method for the prediction of future carbon prices. [ABSTRACT FROM AUTHOR]

Creating ultrathin, mountable fibers from a wide range of polymeric functional materials has made electrospinning an adequate approach to producing highly flexible and elastic materials. In this paper, electrospinning was utilized to produce thermoplastic polyurethane (TPU) nanofibrous membranes for the purpose of studying their thermal and mechanical properties. Towards a study of the effects of fiber orientation and multi-walled carbon nanotubes (MWCNTs) as a filler on both mechanical and thermal characteristics of electrospun TPU mats, an experimental comparison was held between unidirectional and randomly aligned TPU and TPU/MWCNTs nanofibrous structures. The incorporation of MWCNTs into randomly oriented TPU nanofibers resulted in a significant increase in Young's modulus (E), from 3.9 to 7.5 MPa. On the other hand, for unidirectionally spun fibers, Young's modulus increased from 17.1 to 18.4 MPa upon the addition of MWCNTs. However, dynamic mechanical analysis revealed a different behavior. The randomly oriented specimens exhibited a storage modulus with a significant increase from 180 to 614 MPa for TPU and TPU/MWCNTs mats, respectively, and a slight increase from 119 to 143 MPa for unidirectional TPU and TPU/MWCNTs mats, respectively. Meanwhile, the loss modulus increased with the addition of MWCNTs from 15.7 to 58.9 MPa and from 6.4 to 12 MPa for the random and aligned fibers, respectively. The glass transition values for all the mats fell in the temperature range of – 60 to − 20 °C. The thermal degradation of the membranes was not significantly affected by the addition of MWCNTs, indicating that the mixing of the two constituents did not change the TPU's polymer structure and that the TPU/MWCNTs nanocomposite exhibited stable thermal degradation properties. [ABSTRACT FROM AUTHOR]

New innovations in microscopic or molecular profiling methods that provide a high level of information with regard to either spatial or molecular properties, but typically not both, have been a major driver of recent advancements in cancer research and diagnoses. The first malignant tumour to develop in women is now breast cancer. The best way to enhance a breast cancer patient's prognosis is through early identification and treatment. The qualitative differential diagnosis of breast nodules is crucial for detection as well as diagnosis of breast cancer. Importance of breast MRI is growing as a result of the quick advancement of MRI technology, particularly the use of high field strength and ultra-high field strength. This research proposes novel technique in carbon pattern based polymeric nanofabrication in breast image based on contrast improvement and feature extraction with training using machine learning techniques. Here the input breast image has been analysed for molecular cell analysis by nano material by segmentation using curvelet multi-interval histogram normalization. Then the segmented image features are extracted using hybrid weighted regularized spatial Boltzmann machine architectures. Experimental analysis is carried out based on various breast image dataset in terms of random accuracy, sensitivity, AUC, F-measure, dice coefficient, NSE. [ABSTRACT FROM AUTHOR]

The reaction of methane decomposition is an endothermic process that produces hydrogen without any impurities as a gas product and carbon nanotubes/carbon nanofibers as a solid product. In this study, NiO–MgO catalysts with different nickel loadings (20, 30, 40, and 50 wt. %) were synthesized using the mechanochemical method. The Physicochemical features of the synthesized catalysts were characterized by various methods such as BET, XRD, SEM, TPO, and H2-TPR. The prepared samples were tested in the methane decomposition process at various temperatures under the GHSV value of 48,000 ml/(gcat h). Among the prepared samples, the 50wt.%NiO–MgO exhibited the best activity (40% methane conversion at 575 °C) in this process due to its higher concentration of active metal and better catalyst reducibility. Also, the effect of different parameters such as feed ratio, GHSV, and calcination temperature was studied on the activity of this catalyst. The results showed that with the increase of GHSV and feed ratio, the methane conversion decreased due to the lesser contact time and diminishing the proportion of accessible active sites per methane entrance molecules. Moreover, the results showed that with the rise of calcination temperature from 500 to 700 °C, the methane conversion decreased due to the sintering of nickel particles. The results also showed that the addition of 15 wt.% Cr2O3 to the catalyst formulation improved the catalytic performance and lifetime in the thermocatalytic decomposition of methane due to the higher reducibility and dispersion of the active species on the catalyst surface. [ABSTRACT FROM AUTHOR]

The fabrication and functionalization of three-dimensional (3D) MXene are vital for diverse high-performance applications. Herein, the construction of 3D porous MXene architecture and its functionalization with graphene are synchronously implemented by breath figure method. 3D porous rGO/MXene with multi-scale pores is prepared by simply casting the mixture of GO/surfactant and MXene/surfactant solution under humid environment and the subsequent reduction process. The aggregation inhibition of GO and MXene nanosheets at multi-scale caused by surfactant intercalation and the formation of 3D porous structure, as well as the increase in surface area induced by the introduction of GO, enlarged lamellar spacing and multi-scale porous structure endow porous rGO/MXene with excellent electrochemical performance. The synergy of rGO and MXene leads to further improvement in electrochemical property and its stability. Low detection limit, good anti-interference, repeatability, reproducibility, long-range stability and accuracy of actual sample testing are exhibited when porous rGO/MXene is used for electrochemical detection of DA. Furthermore, the electrochemical performance could be controlled via tuning the porous structure and ratio of GO and MXene. This study not only demonstrates the superiority of porous rGO/MXene toward electrochemical sensing, but also proposes a simple and universal method for controllable construction and functionalization of 3D MXene architecture. [ABSTRACT FROM AUTHOR]

A flexible wearable electrode consisting of nickel–cobalt sulfide (NCS) nanowires was fabricated in this study. Self-supporting NCS was grown in situ on porous carbon nanofibers without a binder as a novel material for supercapacitor electrodes. The NCS nanowires were grown using cyclic voltammetry electrodeposition, which proved to be a fast and environmentally friendly method with good controllability of the material structure. One-dimensional carbon nanofibers (C) have high surface-area-to-volume ratios, short ion transmission distances, excellent mechanical strengths, and remarkable flexibilities. Moreover, the NCS@C flexible electrode exhibited a synergetic effect with the active compounds, and the dense active sites were uniformly distributed across the entire surface of the carbon fibers, enabling rapid electron transport and enhancing the electrochemical properties of the NCS@C nanowires. The NCS@C achieved specific capacitances of 334.7 and 242.0 mAh g−1 at a current density of 2 A g−1 and high current densities (up to 40 A g−1), respectively, corresponding to a 72.3% retention rate. An NCS@C-nanofilm-based cathode and an activated-carbon-based anode were used to fabricate a flexible asymmetric supercapacitor. The device exhibited high energy and power densities of 12.91 Wh kg−1 and 358 W kg−1, respectively. [ABSTRACT FROM AUTHOR]

Formulating carbon emission reduction at the regional level is key to achieving the "dual carbon" strategy. A composite model is used to analyze the carbon emission reduction in Huaibei City based on the data from 2012 to 2021 and predict its change trend of carbon emission from 2022 to 2030. The study finds that: (1) the effects of observed factors on carbon emission in Huaibei City are complicated. Among them, the secondary industry has the greatest impact on carbon emission (weight is 0.32), and it is the key constraint factor of carbon emission. Population has the smallest impact on carbon emission (weight is 0.13), but its obstacle effect is significant. (2) The observed factors have a significant positive effect on the "dual carbon" strategy, but the improvement pressure is high. Among them, the conditions of all indicators have been improved except population, and it is found that each indicator can reach the level I before 2030, the "dual carbon" strategy can be achieved. This study deepens the understanding of regional carbon emission in China and the following conclusions are formed: (1) Grasping the carbon reduction effect of urbanization on the population to consolidate the new model of low-carbon development. (2) Identifying the key areas of carbon emission reduction to build a low-carbon emission oriented industrial system. (3) Strengthening the technological innovation of carbon emission reduction to achieve the strategic goal of "dual-carbon". [ABSTRACT FROM AUTHOR]

An electrochemical immunosensor based on carbon nanofibers (CNFs) and gold nanoparticles (AuNPs) was developed for detecting anti-Toxoplasma gondii antibodies (anti-T. gondii) IgG in human serum. CNFs were produced using electrospinning and carbonization processes. Screen-printed carbon electrode (SPCE) surface was modified with CNFs and AuNPs which were electrodeposited onto the CNFs. Then, T. gondii antigen was immobilized onto the AuNPs/CNFs/SPCE. Afterward, anti-T. gondii IgG positive serum samples were coated on the modified electrode and assessed via adding anti-human IgG labeled with horseradish peroxidase (HRP) enzyme. The morphology of SPCE, CNFs, and AuNPs/CNFs/SPCE surface was characterized using field emission scanning electron microscopy (FESEM) equipped with energy dispersive spectroscopy (EDS). Characterization of CNFs was evaluated by Raman spectroscopy and X-ray diffraction (XRD). Electrochemical characterization of the immunosensor was verified using cyclic voltammetry (CV), and electrochemical response of modified electrode for anti-T. gondii IgG was detected via differential pulse voltammetry (DPV). This immunosensor was detected in the range 0–200 U mL−1 with a low detection limit (9 × 10−3 U mL−1). In addition, the proposed immunosensor was exhibited with high selectivity, strong stability, and acceptable reproducibility and repeatability. Furthermore, there was a strong correlation between results obtained via the designed immunosensor and enzyme-linked immunosorbent assay (ELISA) as gold standard. In conclusion, the developed immunosensor is a promising route for rapid and accurate clinical diagnosis of toxoplasmosis. [ABSTRACT FROM AUTHOR]

Highlights: Electrospinning combined with structural engineering to construct 0D@2D@1D hierarchical heterogeneous interfaces. A "mechanical response" model was constructed to explain the stress transfer mechanism of fibrous membranes with 2D@1D structures. The "One for All" fibrous membrane combines excellent flexibility, mechanical properties, waterproof, and electromagnetic protection. The development of wearable multifunctional electromagnetic protective fabrics with multifunctional, low cost, and high efficiency remains a challenge. Here, inspired by the unique flower branch shape of "Thunberg's meadowsweet" in nature, a nanofibrous composite membrane with hierarchical structure was constructed. Integrating sophisticated 0D@2D@1D hierarchical structures with multiple heterointerfaces can fully unleash the multifunctional application potential of composite membrane. The targeted induction method was used to precisely regulate the formation site and morphology of the metal–organic framework precursor, and intelligently integrate multiple heterostructures to enhance dielectric polarization, which improves the impedance matching and loss mechanisms of the electromagnetic wave absorbing materials. Due to the synergistic enhancement of electrospinning-derived carbon nanofiber "stems", MOF-derived carbon nanosheet "petals" and transition metal selenide nano-particle "stamens", the CoxSey/NiSe@CNSs@CNFs (CNCC) composite membrane obtains a minimum reflection loss value (RLmin) of -68.40 dB at 2.6 mm and a maximum effective absorption bandwidth (EAB) of 8.88 GHz at a thin thickness of 2.0 mm with a filling amount of only 5 wt%. In addition, the multi-component and hierarchical heterostructure endow the fibrous membrane with excellent flexibility, water resistance, thermal management, and other multifunctional properties. This work provides unique perspectives for the precise design and rational application of multifunctional fabrics. [ABSTRACT FROM AUTHOR]

Background: The era of nanotechnology become widespread for research and human resource development due to its functionalized tuning with economical, eco-friendly, effective and sustainable end-products. Hence, the present review illustrates the biogenic fabrication of platinum nanoparticles (PtNPs) through the different sustainable and cheaper approaches. Over the physicochemical-based nanotechnology, the biogenic active substances-based synthesis displayed the more promising candidature due to its non-toxic, Broad-spectrum applicability and defendable type character. The biogenic synthesis method is capable with and without capping and highly motif of reducing agents. The morphology and stability of synthesized PtNPs are mostly mediated by various experimental conditions such as pH, temperature, incubation time, concentrations of biomaterials and salts or enzymes used. Hence, the review is aiming to discuss the methodology of biogenic synthesis of PtNPs by plant stem, root, leaf, flower, fruit, extracts, algae, fungi and egg yolk. Also, we have illustrated the pharmaceutical drug model application and its adverse effect. Short conclusion: Synthesized PtNPs are open a new trend in catalyst, drug and its carrier and in cancer treatment. PtNPs are utilized as a new therapeutic agent for inhibiting the microbial pathogens with non-toxic behavior. The characterization of PtNPs could estimate the bio-sensitized properties which leads the commercial applications. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for the detection of tartrazine (Tz), a synthetic azo dye customarily found in commercial soft drinks, is herein reported. This sensor is based on a carbon paste electrode (CPE) with gold nanoparticles (AuNP) anchored in carbon nanofibers (CNF). The CNF/AuNP nanocomposite was characterized by scanning electron microscopy (SEM), energy dispersive X-Ray spectroscopy (EDS), X-ray diffraction (XRD), and electrochemical impedance spectroscopy (EIS). The electrochemical evaluation and detection of Tz was carried out by using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). In terms of sensibility, the CNF/AuNP-CPE electrochemical sensor exhibits a linear range of 3.29 – 49.50 µmol L−1 with a coefficient of determination r2 of 0.9946, a limit of detection (LOD) of 0.8 ± 0.07 µmol L−1, and a limit of quantification (LOQ) of 2.64 ± 0.23 µmol L−1. Furthermore, the proposed sensor exhibits excellent selectivity toward Tz in the presence of the sunset yellow dye, and other interferents such as sodium benzoate, NaNO3, NaHCO3, glucose and citric acid. In addition, a DFT computational study suggests that noncovalent interactions contribute to the stabilization of the Tz-AuNP assemblies at the electrode/electrolyte interface. The optimal reproducibility, repeatability, and stability during the Tz detection in commercial soft drinks makes CNF/AuNP-CPE an appealing electrode for analytical purposes. [ABSTRACT FROM AUTHOR]

The parameters of the synthesis of catalysts by the solution combustion method using oxalic acid as a reducing agent were investigated. The activity of the catalysts was determined in the production of hydrogen and carbon nanofibers by the catalytic decomposition of methane. The efficiency of oxalic acid was demonstrated in the preparation of a nickel catalyst (90% Ni/10% Al2O3), which does not require the preliminary reduction with hydrogen. Regression analysis identified that the yields of carbon and hydrogen are most strongly affected by temperature among other synthesis parameters. [ABSTRACT FROM AUTHOR]