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Found on the surfaces of transition metal oxides or sulfides are metal cations and oxygen or sulfur anions (Mn+-O2− or Mn+-S2−) with diverse catalytic functions as redox sites (Mn+-O2− → M-□), Brønsted acid sites (M-OH), and Lewis acid–base sites (Mδ+-O2−). These active site pairs often work together in catalyzing the chemical transformation in cascade reactions. This article describes several experimental strategies, combining kinetic and titration methods, to decouple the effects of surface site occupation on turnover rates, identify the kinetic bottlenecks, remove the effects arising from deactivation, as well as elucidate the potential participation of multiple types of active sites. Using a correlative approach in connecting the rate dependencies and titration studies, one could pinpoint the key factors that contribute to the rates and interpret the measured rates in terms of molecular events on the surfaces. [ABSTRACT FROM AUTHOR]

• A new dynamic rod worth measurement method based on the transient spatial factor has been proposed. • A transient spatial factor is proposed to consider the transient spatial effect caused by the change in the shape distribution of neutron flux. • A new dynamic rod worth measurement method based on the transient spatial factor is applied to a commercial CNP1000 reactor employing the measurement data. • A comparison is made between the control rod worth measured by the transient spatial factor and that measured by the static spatial factor and dynamic spatial factor. Given the responsibility of the control rod for controlling reactivity in commercial PWRs, accurate measurement of it is of great significance. To measure the control rod worth in the zero-power physics test, this paper proposes a new dynamic rod worth measurement method by using the definition of the transient spatial factor. During the process of dynamic rod worth measurement, it was found that the rapid movement of the control rod in the timescale of seconds causes a substantial change in the shape of neutron flux in the 3D space, which significantly affects the power-range detector signals, resulting in an incorrect estimation of reactivity by the reactimeter. To eliminate the transient spatial effect of neutron flux, a transient spatial factor is proposed, which is provided by calculating the process of control rod insertion based on the 3D time-dependent neutron diffusion calculation. Thus, a new DRWM method based on the transient spatial factor has been applied and validated in a CNP1000 reactor. Results of the control rod worth are presented in this paper to demonstrate its performance in engineering applications. [ABSTRACT FROM AUTHOR]

Fiber‐based multimodal sensors with electrical/optical signals are highly desired for next‐generation wearable electronics. Despite the remarkable progress in this area, achieving large‐scale knittable, washable, and self‐healing performance in fiber‐based multimodal sensors simultaneously remains a great challenge. Here, a smart fiber capable of exhibiting piezoresistive/luminescent properties based on an H‐bonding connected multilayered core–shell nanostructure is developed. The core principle of this design involves constructing strong interfacial interactions between the fiber layers, which results in a sensor with high sensitivity (gauge factor = 12383500), exceptional water resistance, and robust self‐healing properties (tensile strength 30.9 MPa, healing efficiency 72.9%). Unlike traditional fiber‐based sensors where elaborate nanostructures are prone to shedding during knitting, this strategy enables the fiber sensors with excellent knittability to be patterned in the fabric, improving both optical and electrical sensitivities. This work is anticipated to make a significant contribution to the further development of wearable electronic products and visual human–computer interaction electronic devices. [ABSTRACT FROM AUTHOR]

Biomass‐based catalysis has drawn a gradually increased attention due to its eco‐friendliness, cost‐effective, and good reusability. In this work, a novel metal–organic framework (MOF) derived nitrogen‐doped zinc oxide carbon (ZnO/N/C) nanocomposites were synthesized on pine cone by solvothermal and carbonization method. Scanning electron microscopy, x‐ray diffractometer, and x‐ray photoelectron spectroscopy were employed to confirm the presence of N‐doped ZnO rod‐like nanostructures on the as‐prepared composites. The obtained ZnO/N/C nanocomposites were employed as catalytic materials for the decomposition of methylene blue (MB) dye and adsorption of formaldehyde (HCHO). The ZnO/N/C nanocomposites can degrade more than 90% of the MB solution within 90 min under visible light irradiation, besides, they can rapidly absorb and decompose HCHO. The high‐catalytic performance of ZnO/N/C nanocomposites can be attributed to the high‐superficial area of ZIF‐8, the carbonization that ensures the high conductivity and high‐slight absorption of carbon skeleton materials, and the accelerated transfer of photogenerated electrons. This simple and green preparation method has promoted the sustainable utilization of biomass resources with great significance for application of carbon‐based porous materials in catalytic field. Highlights: MOF derived ZnO/N‐doped carbon nanocomposites were successfully synthesized.Presence of N‐doped ZnO rod‐like nanostructures on carbon nanocomposites.ZnO/N/C nanocomposites could be used as a catalyst for MB photodegradation.ZnO/N/C nanocomposites can be readily absorption and decompose of HCHO. [ABSTRACT FROM AUTHOR]

H 2 production by steam methane reforming (SMR) is an energy-intensive process at high reaction pressure and temperature. The objective of present work is to improve the efficiency of H 2 production by optimizing turbine-integrated SMR-coal gasification process (SMRT-CG). The economic analysis of turbine-integrated SMR process (SMRT) was investigated with decision variables, such as flowrate of natural gas, reaction pressure, and turbine discharge pressure. The optimal price of H 2 production was competitive after the addition of turbine. Genetic algorithm (GA) together with waste reduction (WAR) algorithm were used to evaluate the environmental impact of optimal SMRT. Optimization by non-dominated sorting genetic algorithm (NSGA-II) suggested that the total annual profit (TAP) would increase by $1.04 million/y while the effective process exergy loss (ΔE xl,eff) would be reduced by 17.4%. Instead of serving as the fuel of SMR furnace, the H 2 in tail gas was separated by a pressure-swing adsorption unit. After removing the concentrated CO 2 , the H 2 and CH 4 were introduced to a coal gasification plant (CG) to promote the syngas production. Further analysis confirmed that higher H 2 formation rate of SMRT-CG process was realized compared to the original CG process due to the chemical looping with the tail gas. • Enhanced SMR with plant integration was developed for reduced CO 2 emissions. • SMR process with turbine was optimized by GA, NSGA-II and WAR algorithm. • Significant increase of H 2 production and output work was achieved in proposed SMR. [ABSTRACT FROM AUTHOR]

The development of wearable electronic devices has greatly stimulated the research interest of textile-based strain sensors, which can effectively combine functionality with wearability. In this work, the fabrication of highly stretchable and compressible strain sensors from weft-knitted spacer fabric was reported. Carbon nanotubes and polypyrrole were deposited on the surface of fabric via an in situ polymerization approach to reduce the electrical resistance. The as-fabricated WSP-CNT-PPy strain sensor exhibits high electrical conductivity and stable strain-sensing performance under different stretching deformations. The WSP-CNT-PPy strain sensor can be stretched up to 450% and compressed to 60% with a pressure of less than 50 KPa, which can be attributed to the unique loop and interval filament structures. The distinguishing response efficiency of WSP-CNT-PPy can effectively detect faint and strenuous body movements. In addition, the electrochemical behavior of WSP-CNT-PPy was also characterized to study the comprehensive properties. The electro-heating performance was also evaluated for feasible Joule heater applications. This work demonstrates the practicability of WSP-CNT-PPy strain sensor fabric for real-time monitoring in promising wearable garments. [ABSTRACT FROM AUTHOR]

Graphene/cotton fibers show significant promise in wearable energy storage due to their low cost, porous structure, and exceptional integration ability into wearable systems. However, the eco-unfriendly reductants and standalone electric double-layer capacitor hindered their application. Herein, a green and rapid hydrothermal-electrodeposition method was proposed to fabricate polyaniline (PANI) decorated reduced graphene oxide (rGO)/cotton yarns without using any chemical reductants and oxidants. The PANI/rGO/cotton (PRC) yarn exhibited porous conductive network, structural controllability, and mechanical flexibility. Additionally, the PRC yarn electrode delivers a fast electron transport and ion migration, synergistic energy storage contribution, and a controllable capacitance (up to 81.2 mF cm−1 at 0.2 mA cm−1). The assembled yarn supercapacitor shows a good capacitance (19.8 mF cm−1 at 0.08 mA cm−1), excellent energy-power density (2.7 μWh cm−1 at 40 μW cm−1), and great capacitance retention. This green fabrication of PRC yarns brings new insights into the development of wearable energy storage. [Display omitted] • Polyaniline/reduced graphene oxide/cotton (PRC) composite yarn was made. • A green and rapid hydrothermal-electrodeposition method was proposed. • PRC yarn shows porous conductive network, structural controllability, and flexibility. • PRC yarn electrode shows fast electron/ion transport and synergistic capacitance. • PRC yarn supercapacitor shows good specific capacity, power density and cycle ability. [ABSTRACT FROM AUTHOR]

The development of cooling textiles has a significant impact on energy saving and cost‐effectiveness in the context of global warming. Engineering textiles with cooling performance while maintaining their intrinsic traits, for example, lightweight, washable, comfort, and durability, is a great challenge in developing personal cooling garments. Here, the synthesis of nanodiamond/polydopamine/wool (ND‐PDA‐wool) nanocomposites through a facile dip‐coating approach is demonstrated. Different types of ND including detonation ND (DND), carboxylated ND (ND‐COOH) and hydroxylated ND (ND‐OH), are used, and dopamine templating is applied to achieve strong adhesion and bonding between fiber and ND. The morphology, structure, and properties of the as‐coated fabrics are characterized, and the cooling performance together with comfort are measured. Due to the excellent thermal conductivity of ND, the temperature difference between the coated fabrics and uncoated ones is around 2.4–3.9 °C within a short time span of 30 min. The coated ND‐PDA‐Wool fabrics demonstrated enhanced thermal stability and improved mechanical properties with excellent durability, and the water absorbency is greatly enhanced with well‐maintained air permeability. ND‐PDA‐wool composite fabrics offer a strategy to develop durable, lightweight, washable, and comfortable cooling textiles with immense potential in energy saving and reducing space cooling costs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Collagen/carboxylated CNF composite aerogels are successfully fabricated. • CDs can promote the in vitro self-assembly behavior of collagen. • CDs are beneficial for improving the properties of the collagen composite aerogels. • Composite aerogels have an excellent pH-responsive for drug delivery system. pH-responsive materials have great potential for use in various advanced fields, such as microreactors and drug delivery. This work proposes a promising strategy for preparing composite aerogels with pH-responsive properties based on collagen (COL) and TEMPO-oxidized cellulose nanofibers (CNFs) through the self-assembly behavior of COL molecules for controlled-drug release. COL fibrils and carboxylated CNFs (cCNFs) exhibited a high-density, physical cross-linked supramolecular double network structure. Specifically, cyclodextrins (CDs) were introduced to optimize the structural stability and slow-release capability of the composite aerogels. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analyses were used to characterize the structure of the aerogels, and the swelling behavior and water contact angle of the aerogels were evaluated. Using 5-fluorouracil (5-FU) as the model drug, the slow-release mechanism was subsequently revealed. Compared with the COL aerogels and COL/cCNF composite aerogels, the COL/cCNF@CD composite aerogels exhibited enhanced structural stability and slow-release performance through the synergistic enhancement effect of cCNFs and CDs. The aerogels also exhibited sensitivity to pH for regulating 5-FU release, and the COL composite aerogels with CDs and cCNFs maintained excellent cytocompatibility. In conclusion, CDs had a positive effect on the structural stability and pH-responsiveness of the composite aerogels and promoted the possible utilization of aerogels in drug delivery systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The expandable graphite-based cement composite (GCC) was fabricated. • The GCC exhibits with accurate and sensitive temperature sensing performance. • The GCC exhibits excellent mechanical and sensing stability when exposed to flame. • The GCC can be easily integrated into a building and transmit a fire alert. Fire alarms in buildings are essential for safety. However, due to the poor conductivity of cement, it remains a challenge to detect fire without the assistance of other monitoring equipment. In this study, a fire alarm cement composite containing expandable graphite, carbon fiber, and ordinary Portland cement that can achieve ultrasensitive temperature monitoring and indoor climate control in a building is developed. Homogeneously distributed expandable graphite in this smart cement rapidly expands under high temperatures, forming new electrically conductive pathways. This results in excellent temperature sensing performance, with a temperature coefficient of resistance of − 0.467 %/°C in the range of 220 °C–400 °C. The smart cement can be easily integrated into a building to transmit a fire alert to a computer, mobile phone, or visual alarm device in a timely manner. Furthermore, this smart cement exhibits higher flexural strength in harsh environments compared to ordinary cement. This smart cement exhibits potential to considerably broaden cement applications and be highly desirable for next-generation smart building materials. [ABSTRACT FROM AUTHOR]

Recycling of photocatalyst in wastewater treatment is a big challenge. Fixation of photocatalyst on a flexible surface of solid substrates is a promising solution. In this work, copper ferrite (CuFe 2 O 4) particles were loaded onto polydopamine (pDA) pretreated ceramic/polyester fabrics (CPF) via coprecipitation. The CPF not only acts as loading material for CuFe 2 O 4 particles, but also makes this photocatalyst convenient to recycle. The morphology, elemental composition and structure of the as-fabricated CPF/CuFe 2 O 4 were characterized by scanning electron microscope (SEM), Fourier transform Infrared (FT-IR) spectrometer, X-ray photoelectron spectroscopy (XPS) and X-ray diffractometer (XRD). The degradation rate of methylene blue (MB) by the CPF/CuFe 2 O 4 photocatalyst reached to 98.2% under visible light irradiation for 80 min, reflecting the excellent photocatalytic activity of the composites. The CPF/CuFe 2 O 4 demonstrated good photostability and recoverability, indicating its great potential in wastewater treatment. Moreover, the degradation mechanism and possible degradation pathway of MB by CPF/CuFe 2 O 4 photocatalyst were investigated. [ABSTRACT FROM AUTHOR]

Novel water and dye-free heat treatment method was used to color wool yarn. The heat treatment can not only give the white wool yarn new color but also minimize the yarn hairiness. The influences of heating treatment temperature and time on the wool yarn color were investigated. The microstructure, twist, hairiness, wear resistance, moisture regain and tensile strength of the wool yarn were evaluated to analyze the physical and mechanical properties changes after heat treatment. The results showed that the color strength of wool yarn increased with increasing the heat treatment temperature and time. The hairs equal to or longer than 3 mm reduced significantly after heat treatment. The microstructural structure has no significant change after heat treatment, the unique overlapping scales structure on the surface still observed clearly by the SEM. The tensile strength and wear resistance of wool yarn would decrease with increasing heat treatment temperature and time, and the tensile strength retention was higher than 80% after heat treatment which could meet the requirement in daily applications. Therefore, the heat treatment is an environmentally friendly method to endow wool yarn color and it has a potential in the textile industry. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide combined with acid treatment demonstrates its respective characteristics for the separation of lignocellulosic biomass. Herein, holocellulose was extracted from Cattail leaves (CL) by a two-step treatment with alkali and hydrogen peroxide-acetic acid (HPAA). Then carboxylated nanocellulose was hydrolyzed with a mixed organic/inorganic acid. The chemical composition of the holocellulose and the physicochemical properties of the separated carboxylated nanocellulose were comparable. Carboxyl groups were introduced on the nanocellulose as a result of the esterification process with citric acid (CA), which endows the nanocellulose with high thermal stability (315–318 °C) and good light transmission (>80 %). Furthermore, morphological analyses revealed that nanocellulose had a spider-web-like structure with diameter between 5 and 20 nm. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide combined with acid treatment demonstrates its respective characteristics for the separation of lignocellulosic biomass. Herein, holocellulose was extracted from Cattail leaves (CL) by a two-step treatment with alkali and hydrogen peroxide-acetic acid (HPAA). Then carboxylated nanocellulose was hydrolyzed with a mixed organic/inorganic acid. The chemical composition of the holocellulose and the physicochemical properties of the separated carboxylated nanocellulose were comparable. Carboxyl groups were introduced on the nanocellulose as a result of the esterification process with citric acid (CA), which endows the nanocellulose with high thermal stability (315–318 °C) and good light transmission (>80 %). Furthermore, morphological analyses revealed that nanocellulose had a spider-web-like structure with diameter between 5 and 20 nm. [ABSTRACT FROM AUTHOR]

Nanofibers are ideal for the fabrication of fiber-based sensors owing to the wide applicability of such sensors in various fields. However, achieving high sensitivity and excellent tensile properties while maintaining high electrical conductivity in such sensors is difficult. This study proposes a simple fabrication method for a helical conductive yarn, core–sheath helical yarn (CSHY), in which the electrospun thermoplastic polyurethane (TPU) /boron nitride (BN) film is used as the fibrous material and coated with a liquid metal (LM), EGaIn. The fiber is then stretched and twisted to obtain the CSHY with high sensitivity, tensile stability, and durability as well as fast response and recovery. Experimental results show that the sensor fabricated by weaving the CSHY has a water contact angle of 143.2°, indicating that it can be used for human motion monitoring and underwater applications. In addition, the LM has excellent electrical conductivity and thermal conductivity and exhibits a synergistic effect with BN that is uniformly arranged along the fiber length. Thus, the fabric-based sensor exhibits excellent heat-dissipation, temperature-sensing, and electric-heating performances. Consequently, the proposed multifunctional smart yarn exhibits excellent strain sensing, self-controlled thermal management, and hydrophobic performance, with potential applications in future wearable electronics. • A strain sensitive and multifunctional smart yarn was fabricated with a core–sheath helical structure. • The yarn exhibited excellent strain sensing performance even underwater. • Potential applications include temperature monitoring, thermal management and joule heating were demonstrated. [ABSTRACT FROM AUTHOR]

Inorganic photocatalysts with excellent photocatalytic reactivity have significant potential for wastewater treatment. In this study, using sodium copper chlorophyllin (SCC) as a copper source, Cu atoms were incorporated into the center cavities of g-C 3 N 4 nanosheets by hydrothermal-calcination combined processes. Cu atoms doping led to a narrower optic band gap and the dramatic improvement in photocurrent response as well as corresponding declines in the intensity of electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) spectra. Consequently, the photocatalytic property the Cu/g-C 3 N 4 was enhanced dramatically as evidenced by a 53.4% increase in the photocatalytic degradation rate of tetracycline. Superoxide ions and hydroxyl radicals were found to be the main reactive oxygen species (ROS) causing the degradation. The increased photocatalytic capability of Cu/g-C 3 N 4 might be attributed to the increased chance of intersystem crossing in photosensitizing process of Cu/g-C 3 N 4 as well as the lowered adsorption energy required for the adsorption of O 2 to the catalyst. Minor decline in the photocatalytic efficiency of Cu/g-C 3 N 4 was observed while the crystal structure of the Cu/g-C 3 N 4 remained stable after three cycles of tetracycline degradation. These results indicated the good stability of Cu/g-C 3 N 4 and the possibility of recycling the catalyst during the photocatalytic applications. [Display omitted] • SCC as a copper source was incorporated into the g-C 3 N 4 nanosheets by hydrothermal-calcination combined processes. • The Cu/g-C 3 N 4 samples showed good photocatalytic property in degrading tetracycline solution. • O 2 •− and •OH were found to be the main reactive oxygen species (ROS) causing the degradation. • A possible catalytic mechanism of Cu/g-C 3 N 4 nanocomposites is proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • A flexible and highly sensitive strain sensor was developed by using carbonized biomass Juncus effusus fiber. • The 3D fractal composite structure showed robust mechanical strength and excellent sensitivity. • Reliable sensing performance was achieved with mechanism revealed. • Potential applications include health care monitoring and human motion monitoring were demonstrated. • The promising potential of energy conversion and harvesting was demonstrated. Fabricating strain sensors with environmental-friendly, stretchable, and highly sensitive properties remains challenging. Nature has designed an abundance of biomaterials with distinctive biological structures, which may promote the development of ideal strain sensors. Herein, we present a carbonized Juncus effusus (CJE) fiber-based wearable electronic for strain sensing and energy harvesting. The CJE strain sensor demonstrated a combined superiority of large tolerable strain (over 80%), high sensitivity (GF 4.5–31.0), low detection limit (0.1% strain), fast response (within 100 ms), and excellent durability (3500 cycles), which benefit from the self-similar and homogenous three-dimensional (3D) networks of CJE fibers. Moreover, CJE-based woven fabrics exhibited enhanced sensing characteristics (GF up to 101.9, over 110% strain) and great application prospects as triboelectric nanogenerators (TENGs). Finally, the applications in detecting human activities and energy transformation were evaluated in detail. The structural advantages made CJE as a promising candidate for the feasible integration of flexible strain sensors and portable power source in wearable electronics. [ABSTRACT FROM AUTHOR]

• A core-sheath sensing yarns was fabricated via scalable friction spinning. • The yarn exhibited excellent heat resistance and stretchability simultaneously. • High-temperature alarm could be transmitted through stretching and thermosensation. Electronic textiles with functions of temperature monitoring and human motion detection have attracted considerable interest, especially those which can be operated under extreme conditions such as high temperature. However, the restricted working conditions and poor stretchability have limited the practical application of most reported electronic textiles. Herein, we report a facile and scalable strategy to fabricate flame-resistant sensing yarn with a core–sheath structure for temperature monitoring and strain sensor applications via a large-scale spinning technique. The hierarchical yarn comprises a spandex filament as the core, carbon nanotube (CNT)-coated aramid fibers as the middle layer, and aramid fibers as the sheath. The obtained spandex/CNT@Aramid/Aramid (SCAA) yarn exhibited stretchability up to 160 % with excellent thermal resistance, outstanding thermal insulation performance, and temperature monitoring ability within a wide-range of 50–400 °C. Additionally, SCAA-based textiles showed excellent strain sensing performance in a wide operating temperature range (0–300 °C). Based on the above, a SCAA-based textiles which can transmit high-temperature alarms through active (stretching) and passive (thermosensation) modes was designed, enabling temperature monitoring presenting at extremely high temperatures. We believe this work will contribute to the development of practical sensing e-textiles towards applications in harsh environment. [ABSTRACT FROM AUTHOR]

• Polydopamine for in-situ growth of three dimensional(3D) ZnO/Ag nanocomposites. • Raman hot spots of Ag on cluster-like ZnO nanorods for target molecules detection. • Enhanced photocatalysis by inhibited recombination of electron-hole pairs. • PET/pDA/ZnO/Ag SERS substrate with excellent sensitivity and reproducibility. Surface-enhanced Raman scattering (SERS) spectroscopy as an effective method in sensitive detection applications has attracted more and more attentions recently. In this work, polydopamine was taken to achieve the modification of PET film surface for in-situ growth of three-dimensional (3D) ZnO/Ag nanocomposites. Ag nanoparticles on cluster-like ZnO nanorods surface were applied as Raman hot spots for target molecules detection. SEM, XPS, and XRD were used to characterize the microstructures and morphologies of 3D SERS substrates. pATP molecules were selected to measure the sensitivity, uniformity, and durability, the surface-enhanced enhancement mechanism of Raman scattering was analyzed by finite difference time domain (FDDT) simulation method. Malachite green (MG) was further used as the demonstrative pesticide residue, and the catalytic activity was studied by the deoxidization of 4-nitrophenol (4-NP). This work has indicated that SERS substrates exhibited the advantages of facile fabrication process, low cost, high sensitivity, good stability and excellent uniformity, which can be used for the rapid Raman enhanced spectroscopy analysis of environmental pollutants. [ABSTRACT FROM AUTHOR]