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A novel concentrating photothermal reactor with the ultrafast heating rate at around 1800 °C/min was developed to study the effects of CO2 and H2O on coal pyrolysis for oxy-fuel combustion. The mass loss rate with the ultrafast heating rate increased by several decuples than that with the slow heating rate. Coal pyrolysis process with the ultrafast heating rate was promoted by CO2 within 50% concentration but inhibited for a further higher concentration (70%). The addition of H2O into 30% CO2 exhibited a continuous positive role in coal pyrolysis with the ultrafast heating rate. Different from the satisfied prediction of chemical reaction models with the slow heating rates, diffusion models were of higher correlation coefficients for the ultrafast-heating pyrolysis process. The correction factors for CO2 and H2O were determined accordingly, and the modified three-dimensional diffusion mechanism model based on Jander equation (D3 model) well described the ultrafast-heating coal pyrolysis process.

Emission amount of blast furnace gas (BFG) is huge per year and it cannot be directly combusted due to its low heat value. Separating and Enriching CO from blast furnace gas provides an effective w...

Magnetic CoFe2O4 nanoparticles were successfully manufactured through the process of nitrate combustion using anhydrous ethanol as fuel, they together with their intermediate were characterized by thermo gravimetric (TG) analysis, selected area electron diffraction (SAED), transmission electron microscope (TEM), vibrating sample magnetometer (VSM), and X-ray diffraction (XRD). These results indicated a phenomenon that the magnetic CoFe2O4 nanoparticles could be formed at 400 °C, the average grain size, the specific magnetization, and the specific surface area of magnetic CoFe2O4 nanoparticles fabricated at 400 °C for 2 h with 30 mL anhydrous ethanol were corresponding 20 nm, 78.0 Am2/kg and 83.2 m2/kg. Magnetic CoFe2O4 nanoparticles were in application to adsorb methyl blue (MB) of wastewater, and their adsorption performances and electrochemical properties were investigated, the adsorption process data well agreed with the pseudo-second-order kinetics model in concentration ranging from 100 mg/L to 400 mg/L of MB. Compared with Freundlich model, Langmuir model (correlation coefficient R2 = 0.9976) could evaluate the adsorption equilibrium state of MB onto CoFe2O4 nanoparticles at indoor temperature, so the monomolecular layer adsorption mechanism was demonstrated to be the mechanism of the MB molecules' adsorption onto CoFe2O4 nanoparticles.

To shield TiAl alloy from hot corrosion attack, a compact protective coating was fabricated by the combination of aluminizing, anodization and pre-oxidation. The hot corrosion behavior of the coated-TiAl specimen was investigated in the mixture salt consisting of 75 wt.% Na2SO4 and 25 wt.% NaCl at 700 °C. Results indicated that the anodization and pre-oxidation were beneficial to the generation of Al2O3 layer, which could act as a diffusion barrier to prevent the molten salts and oxygen from diffusing into the alloy during exposure to a hot corrosion environment while the aluminizing coating could provide sufficient aluminum source to support the continuous formation of Al2O3 layer. Moreover, the internal stress of the coating was reduced due to the formation of a gradient coating consisting of TiAl3 and TiAl2.

An increasing utilization of flexible healthcare electronics and biomedicine-related therapeutic materials urges the development of multifunctional wearable/flexible smart fabrics for personal therapy and health management. However, it is currently a challenge to fabricate multifunctional and on-body healthcare electronic devices with reliable mechanical flexibility, excellent breathability, and self-controllable joule heating effects. Here, we fabricate a multifunctional MXene-based smart fabric by depositing 2D Ti3C2Tx nanosheets onto cellulose fiber nonwoven fabric via special MXene-cellulose fiber interactions. Such multifunctional fabrics exhibit sensitive and reversible humidity response upon H2O-induced swelling/contraction of channels between the MXene interlayers, enabling wearable respiration monitoring application. Besides, it can also serve as a low-voltage thermotherapy platform due to its fast and stable electro-thermal response. Interestingly, water molecular extraction induces electrical response upon heating, i.e., functioning as a temperature alarm, which allows for real-time temperature monitoring for thermotherapy platform without low-temperature burn risk. Furthermore, metal-like conductivity of MXene renders the fabric an excellent Joule heating effect, which can moderately kill bacteria surrounding the wound in bacteria-infected wound healing therapy. This work introduces a multifunctional smart flexible fabric suitable for next-generation wearable electronic devices for mobile healthcare and personal medical therapy.

Ni-rich cathode material is one of the most promising materials for Li-ion batteries in electric vehicles. However, fading capacity, poor cyclic stability and high pH value are still major challenges, which suppress its practical application. In this study, spherical LiNi0.9Co0.08Al0.02O2 powders with 0.4 wt% TiO2 coating layer were prepared by impregnation–hydrolysis method. Scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) results show that TiO2 is uniformly coated on the surface of LiNi0.9Co0.08Al0.02O2 particle and slightly embedded into LiNi0.9Co0.08Al0.02O2 particles. After 100 cycles at 2.0C, 0.4 wt% TiO2-coated LiNi0.9Co0.08Al0.02O2 electrode delivers much higher discharge capacity retention (77.0%) than the pristine LiNi0.9Co0.08Al0.02O2 electrode (63.3%). The excellent cycling performance of 0.4 wt% TiO2-coated LiNi0.9Co0.08Al0.02O2 electrode at a high discharge ratio is due to a TiO2 coating layer which can effectively reduce the direct contact between cathode material and electrolyte, suppress the oxidation of electrolyte, improve electrical conductivity of the electrode and increase the stability of the structure. With the increase of current density, TCNC sample clearly exhibits enhanced cycling performance with higher capacity retention, and the capacity retention of TCNC increases by 22% at 2.0 C.

AlMgB14–TiB2 composites with ideal structures are successfully prepared by field activated and pressure assisted synthesis. The effects of different TiB2 contents on the relative hardness and toughness of the composites were investigated. The results showed adding TiB2 could both increase the hardness of AlMgB14 and improve the fracture toughness. The TiB2 contributed more to the hardness than to the toughness. The microstructure analysis shows that the main toughening mechanisms of AlMgB14–TiB2 composites are hard phase dispersion strengthening, high-strength interface bonding and the high elastic modulus of TiB2. Therefore, reducing the particle size of TiB2 to nanoscale is an efficient way to improve the toughness and hardness. The results of friction and wear experiment at room temperature have shown that the addition of TiB2 into AlMgB14 enhances the abrasion–resistant property.

In order to alleviate the shortage of global nickel resources, it is imperative to develop low nickel stainless steel. This paper presents a novel approach based on increasing nitrogen and reducing nickel for smelting economical stainless steel. Taking 06Cr19Ni10 stainless steel as the object, the test steels with different nitrogen and nickel content were smelted using vacuum induction furnace (ZG-0.01) under the laboratory conditions, and the effects of alloy content on microstructures, mechanical properties and corrosion properties of the economical stainless steel were investigated. The results show that the microstructure of the tested steel which nitrogen content 0~0.28% and nickel content 5.98~9.63% is still the single austenitic, and the grain size decreases as the nitrogen content increases. Nitrogen deteriorates the impact toughness of the tested steel, and the room temperature impact absorption energy is reduced from 267 J at the nitrogen content of 0 to 228 J at nitrogen content of 0.28%. Rockwell hardness, tensile strength and yield strength increase with the increase of nitrogen content. When the nitrogen content is 0.28%, the optimum mechanical properties of 06Cr19Ni10 steel are obtained. The Rockwell hardness is 95.4 HRB, the tensile strength is 814 MPa, the yield strength is 437 MPa, and the elongation after fracture is 52.5%. The degree of intergranular corrosion of the tested steel is reduced significantly with the increase of nitrogen content, from 0.023 μm to 0.008 μm. The experimental data prove that the composition design concept of increasing nitrogen and reducing nickel is feasible for smelting economical stainless steel.

Hydrogel bioelectronics as one of the next-generation wearable and implantable electronics ensures excellent biocompatibility and softness to link the human body and electronics. However, volatile, opaque, and fragile features of hydrogels due to the sparse and microscale three-dimensional network seriously limit their practical applications. Here, we report a type of smart and robust nanofibrillar poly(vinyl alcohol) (PVA) organohydrogels fabricated via one-step physical cross-linking. The nanofibrillar network cross-linked by numerous PVA nanocrystallites enables the formation of organohydrogels with high transparency (90%), drying resistance, high toughness (3.2 MJ/m3), and tensile strength (1.4 MPa). For strain sensor application, the PVA ionic organohydrogel after soaking in NaCl solution shows excellent linear sensitivity (GF = 1.56, R2 > 0.998) owing to the homogeneous nanofibrillar PVA network. We demonstrate the potential applications of the nanofibrillar PVA-based organohydrogel in smart contact lens and emotion recognition. Such a strategy paves an effective way to fabricate strong, tough, biocompatible, and ionically conductive organohydrogels, shedding light on multifunctional sensing applications in next-generation flexible bioelectronics.

A lithium titanate (Li2TiO3) precursor colloid with high stability was synthesized via a novel inorganic precipitation–peptization method using low cost titanium sulfate as a titanium source, lithium acetate as a lithium source and hydrogen peroxide as a complexing agent. The formation mechanism of the precursor sol was discussed, and the effect of the addition of triethanolamine (TEOA) and sodium dodecylbenzenesulfonate (SDBS) on the colloidal stability was investigated in detail. Samples were characterized with thermogravimetric analysis–differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunnauer–Emmet–Teller (BET) analysis. The results indicate that the colloid stability is enhanced by increased dosage of TEOA and SDBS within a certain range. The best colloid stability is achieved when the amount of TEOA added is 0.75%, and the sol system can remain stable for up to 15 days, which is 7.5 times that of the precursor sol without added surfactant. The optimal amount of added SDBS is 0.125%, and the effect of SDBS on colloid stability is not as significant as that of TEOA. SDBS favors the formation of the crystal structure of Li2TiO3, while TEOA inhibits the ordered arrangement of Li+ in the main crystal layer. The sample (Li2TiO3) surface with SDBS shows a porous structure, which is conducive to the subsequent pickling treatment.

A negative resist composition composed of an acrylic-copolymer-binder resin, a crosslinker, photoinitiators, some agents and solvents has been UV-cured and developed for OverCoat (OC)-Bridge of One Glass Solution (OGS) touch panel (TP) sensor, wherein acrylic-copolymer-binder resin as a key element consisting of N-Phenylmaleimide (N-Pm), Methacrylic acid (MA), Styrene (St) and Isobornyl methacrylate (iBMA) monomers, being designed and synthesized to control the acid value (90-110mgKOH/g), molecular weight (Mw:10,000-20,000) and approximate solubility parameter [10.67-11.05(cal/cm3)1/2]. Here,we demonstrate a OC photoresist applies between two ITO line-films by UV-curing process technology deveoled for OC-Bridge pattern with a kind of acrylic-copolymer-binder resin by ours. Acting as TP sensor, the OC patterns have adequate resistance to solvents, acids and alkalis, good thermal and humid stability, and with excellent transparency and insulation. This OC photoresist, coupled with the acrylic-copolymer-binder resins, provides an unprecedented approach to realize supporting high temperature and humidity OC-Bridge.

Multi-stimuli responsive materials have been attractive for their wide potential applications. The most important but still a challenge is the design of the material and the explanation of how the stimuli affect the molecular structure. Grinding is the most reported mechanical stimuli. But it is very difficult to obtain single-crystals directly after grinding to provide the molecular-level understanding of mechanochromic luminescence (MCL) properties because anisotropic forces can induce crystal collapse, making them unsuitable for single-crystal X-ray analysis. Here we designed a TPE-based Schiff base, N-(2-hydroxy-1-naphthylidene)-1-tetraphenylethenylamine (HL), and first obtained its enol (HLe) and keto (HLk) forms separately. Multi-stimuli response was realized with the aid of transformation of two tautomers. Both the tautomers can respond to grinding. The single crystal X-ray diffraction data of HLe and HLk crystals before and after grinding show that the torsion angles of HLe and HLk molecules change after grinding, which results from the variation of molecular packing and the fine-tuning of molecular conformation. The blue shift of emission bands for HLe and HLk was ascribed to the synergetic effect of crystal size and conformation variation. HLk is vapochromic and could respond to volatile organic solvents via vapor-fuming to generate HLe. This arises from proton transfer from –NH to OC of HLk, in which vapor-induced proton transfer and molecular arrangement variation play a crucial role. There exists the tautomerization of enol and keto forms in solution. HLe and HLk show aggregation-induced emission (AIE) property in THF/H2O, but only the aggregates of HLk form could be obtained no matter whether the original solute was HLe or HLk. HL could also respond to Cu(II) and Al(III) ions in solution. It is an on–off chemosensor for Cu(II) and a chemodosimeter for Al(III) ions.

As a renewable and environment-friendly technology for seawater desalination and wastewater purification, solar energy triggered steam generation is attractive to address the long-standing global water scarcity issues. However, practical utilization of solar energy for steam generation is severely restricted by the complex synthesis, low energy conversion efficiency, insufficient solar spectrum absorption and water extraction capability of state-of-the-art technologies. Here, for the first time, we report a facile strategy to realize hydrogen bond induced self-assembly of a polydopamine (PDA)@MXene microsphere photothermal layer for synergistically achieving wide-spectrum and highly efficient solar absorption capability (≈ 96% in a wide solar spectrum range of 250–1,500 nm wavelength). Moreover, such a system renders fast water transport and vapor escaping due to the intrinsically hydrophilic nature of both MXene and PDA, as well as the interspacing between core-shell microspheres. The solar-to-vapor conversion efficiencies under the solar illumination of 1 sun and 4 sun are as high as 85.2% and 93.6%, respectively. Besides, the PDA@MXene photothermal layer renders the system durable mechanical properties, allowing producing clean water from seawater with the salt rejection rate beyond 99%. Furthermore, stable light absorption performance can be achieved and well maintained due to the formation of ternary TiO2/C/MXene complex caused by oxidative degradation of MXene. Therefore, this work proposes an attractive MXene-assisted strategy for fabricating high performance photothermal composites for advanced solar-driven seawater desalination applications.

Traditional devices, including conventional rigid electronics and machines, as well as emerging wearable electronics and soft robotics, almost all have a single mechanical state for particular service purposes. Nonetheless, dynamic materials with interchangeable mechanical states, which enable more diverse and versatile applications, are urgently necessary for intelligent and adaptive application cases in the future electronic and robot fields. Here, we report a gel-like material composed of a crosslinking polymer network impregnated with a phase changing molten liquid, which undergoes an exceptional stiffness transition in response to a thermal stimulus. Vice versa, the material switches from a soft gel state to a rigid solid state with a dramatic stiffness change of 105 times (601 MPa versus 4.5 kPa) benefiting from the liquid–solid phase change of the crystalline polymer once cooled. Such reversibility of the phase and mechanical transition upon thermal stimuli enables the dynamic gel mechanical transformation, demonstrating potential applications in an adhesive thermal interface gasket (TIG) to facilitate thermal transport, a high-temperature warning sensor and an intelligent gripper. Overall, this dynamic gel with a tunable stiffness change paves a new way to design and fabricate adaptive smart materials toward intelligent control of versatile devices.

In the local droplet etching (LDE) method, the fine split structure (FSS) of quantum dots (QDs) is directly related to the shape of the nanopores formed after annealing. The formation of highly symmetrical nanoporous is the key to the preparation of GaAs/AlGaAs QDs with small FSS. The measurement and characterization of the nano pore shape before and after annealing showed that the density of the nano pore contours is different in different directions, indicating that the slope of the sidewall of the nano pore is different. Therefore, the QDs formed by LDE still have FSS. It has also been observed in experiments that one of the reasons for the asymmetry of the nanoporous is that the etching points covered by the Al droplets on the AlGaAs surface are not in the center of the droplets, which is caused by the supersaturation and maturation of Al atoms during the formation of the droplets. The asymmetry of the annular wall of the nano pore will cause the increase of the FSS of the QDs in the shallow nano pore. When the nano pore is deep enough, the influence of the annular wall of the nano pore on the QDs can be completely ignored, which greatly simplifies the preparation of nano pore. It has certain guiding significance of the preparation of nanoporous required for the growth of QDs with small FSS.

Although YSZ ceramic coating has been used in the field of aeroengines for a long time to protect blades from high temperature erosion, its application on marine engines is still very rare. In this study, YSZ powder was sprayed onto the upper surface of the Al-Si alloy piston by atmospheric plasma spraying. The piston with or without ceramic coatings was applied to the diesel engine bench, and the ship propulsion characteristics test was carried out to study the effect of the coating on the performance of the diesel engine when the ship was sailing. The temperature field results show that under 25% load, the temperature of the top surface of the coated piston is about 30.91 °C higher than that of the conventional piston. The increase in the temperature of the combustion chamber is conducive to better combustion of the fuel in the cylinder of the diesel engine. Therefore, when the marine diesel engine is tested for propulsion characteristics, the thermal efficiency is increased by 5% under the condition of 25% load.

Dynamics of exchange within vitrimer networks are influenced by mobility of the chemical species involved in the exchange reaction, then it can be affected by the crystalline phase when boronic ester bond is introduced into the thermoplastic elastomers with crystalline phase as physical cross-links. In this work, the dynamic dioxaborolane cross-links were introduced into commercial poly(ethylene-α-octene) (POE) with crystalline phases as physical cross-links to prepare POE vitrimers. The results of stress relaxation show that relaxation time (τ) follows an Arrhenius law with the temperature at the melting range for not only POE vitrimers and thermally treated POE vitrimers with dynamic cross-links, but also neat POE with purely physical cross-links. The liquid-to-solid transition temperature can raise to 35.3 °C for POE vitrimers from -42.9 °C of the thermally treated one, due to the constrained mobility by residual crystalline phases. The resulted POE vitrimers maintain a stress at break of higher than 27.5 MPa and an elongation at break of higher than 800% at room temperature. With the temperature increasing, the crystal melting induced weakening of the physical cross-linking in POE decreases the strength, but the storage modulus and the stress at 300% and 500% elongation of POE vitrimers are improved. The properties of POE vitrimers can almost keep unchanged after recycling or healing. All these results show that the introduction of reversible boronic ester bonds is a promising strategy to improve the performances and recyclability of physically cross-linked POE materials.

Using a mixture of dyes to produce a variety of shades is necessary for the industrialization of supercritical fluid dyeing. The solubility of the mixture in supercritical fluid is indispensable for combination dyeing but has been less well-studied. In this study, the solubility of trichromatic disperse dyes (C.I. Disperse Orange 30, C.I. Disperse Red 167 and C.I. Disperse Blue 79) and their blends in supercritical carbon dioxide were measured at temperatures of 333.15, 363.15, and 393.15 K and pressures of 12, 16, 20, and 24 MPa. Considering both the solubility enhancement value and the statistical significance, the solubility of a quaternary system was less than that of a binary system, particularly at higher pressure. To research the relationship between solubility and experimental conditions or properties of the solute, the experimental data were correlated with two semiempirical models (the Kumar–Johnston (K-J) and Sung–Shim (S-S) models) and a phase equilibrium thermodynamic model (a modified Redlich–Kwong equation of state (m-RK-EOS)). The results showed that the calculated solubility by the semiempirical and thermodynamic models had high consistency with the experimental values. In addition, the m-RK-EOS model had better accuracy than the K-J and S-S models for correlating solubility. Therefore, a calculated solubility can be used to offer basic information for the proper design of supercritical fluid dyeing in industry.

In this study, pilot-scale horizontal equipment for zipper tape dyeing in supercritical carbon dioxide (SC-CO2) was designed and successfully constructed. Two horizontal dyeing autoclaves arranged side by side and a color-matching kettle to accelerate the dye dissolution were the two most appealing characteristics of this equipment. The products dyed under the conditions of a temperature of (90 ± 2) °C, pressure of (23 ± 1) MPa, and time of 50 min, presented an excellent color fastness of staining, drying, and wetting, which were all rated at grades of 4–5. The K/S value of the products dyed in SC-CO2 was 6.38, while a value of 5.25 was found in water, even the amount of dyes in the SC-CO2 was lower. The further commercialization of waterless dyeing from pilot-scale studies would have great practical and strategic significance.

Fibrous Sm3+-doped TiO2 (Sm/TiO2) was prepared using collagen fibers as a template. Samples were calcined at different temperatures to prepare TiO2 as well as Sm/TiO2, and effects of Sm-doping on crystallization, crystal transformation and grain size were investigated in detail. The morphology, crystalline structure, diffuse reflection spectrum and element chemical status of the products were characterized using scanning electron microscopy (SEM), X-ray diffractometer (XRD), ultraviolet visible spectrophotometry (UV–Vis DRS) and X-ray photoelectron spectroscopy (XPS), respectively. The photocatalytic performance was evaluated by the following degradation of methyl orange. The results show that the original fiber structure of collagen template is fully preserved when calcinations are carried out at 500–700°C. Sm-doping has an significant effect on crystallization and grain size of TiO2. After samarium doping, the band gap of sample decreased from 3.06 to 3.02 eV, the product has a significant red shift of optical absorption band edge, and the absorbance is also enhanced in visible region. The orbit component of O 1s for 4% Sm–TiO2 is shifted to a higher binding energy. The biggest enhancement in photocatalytic activity was obtained with a dopant amount of 4% samarium calcined at 600°C, and the degradation rate of methyl orange reaches 98.22% after 40 min using metal halide lamp (350 W) as illuminant, which is much higher than that of undoped one.

Solar-driven interfacial water evaporation is regarded as an effective, renewable, and environment-friendly technology for clean water production. However, biofouling caused by the nonspecific interaction between the steam generator and biofoulants generally hinders the efficient application of wastewater treatment. Herein, this work reports a facile strategy to fabricate flexible anti-biofouling fibrous photothermal membrane consisting of a MXene-coated cellulose membrane for highly efficient solar-driven water steam evaporation toward water purification applications. The as-prepared MXene/cellulose photothermal membrane exhibits light absorption efficiency as high as ∼94% in a wide solar spectrum range and a water evaporation rate up to 1.44 kg m-2 h-1 under one solar illumination. Also, the MXene/cellulose membrane shows very high antibacterial efficiency (above 99.9%) owing to the MXene coating as a highly effective bacteriostatic agent. Such a flexible, anti-biofouling, and high-efficiency photothermal membrane sheds light on practical applications in long-term wastewater treatments.

Micron-grade carbon microtubes (CMTs) decorated with layered Ni-Co sulphides of several hundred nanometers and accompanied by Ni-Co sulphides nanoparticles composite structures have been fabricated by facile hydrothermal synthesis method, using willow catkins derived CMTs as carbon scaffolds and ethylene glycol mixture solution containing nickel acetate, cobalt acetate and thiourea as precursors for Ni-Co sulphides. The controllable Ni/Co molar ratios of Ni-Co sulphides can be altered by adjusting the ratio of nickel acetate and cobalt acetate in mixture solution. The electrochemical performance of CMTs/Ni-Co sulphides can be greatly affected by CMTs conductivity, Ni-Co sulphides deposition amounts and crystalline structures. Nevertheless, the hollow tubular structure of CMTs/Ni-Co sulphides composites can provide fast transport channels for ions diffusion while the great conductivity of CMTs scaffolds may facilitate the access of electrons transportation. Owing to this unique structure, the CMTs-1000/Ni2CoS4 composite exhibits an optimal pseudocapacitance (1210 F g−1 at 0.5 A g−1), good rate capability of 83.8% (1014 F g−1 at 10 A g−1) and good cycling durability of 95% retention of the initial value over 3000 charge-discharge cycles, well above the value of pure Ni2CoS4 that is merely 66.1% (1210 F g−1 at 0.5 A g−1 and 800 F g−1 at 10 A g−1) with inferior cycling durability of 78%. Besides, a maximum energy density of 28.1 Wh kg−1 for the CMTs-1000/Ni2CoS4//AC asymmetric supercapacitor (ASC) device can be achieved at power density of 753 W kg−1, and the energy density can still maintain 17.7 Wh kg−1 even at high power density of 17.2 kW kg−1.

Superamphiphobic surfaces generally need a specific combination of low surface energy and re-entrant surface structure. Herein, we have created a hexane suspension of trichloro(1H,1H,2H,2H-tridecafluoro-n-octyl) silane, tetraethyl orthosilicate, silicon dioxide and titanium dioxide nanoparticles and modify a series of filter papers by one-step immersion in 10 min. Superhydrophobic and quasi-superoleophobic properties are obtained for the optimal filter papers, which repel both of polar and non-polar liquids such as water, glycerol, 1,4-butanediol, soybean oil and 1-octadecene with the contact angles of 168°, 158°, 154°, 145° and 121°, respectively. More importantly, the respective contribution of each component to the superhydrophobic and oleophobical property is explicated through a series of comparative experiments based on the optimal suspension prescription. The wettability transformation from quasi-superamphiphobicity to superhydrophilicity after UV irradiation is evaluated and illustrated. What’s more, the patterned paper is successfully used for the colorimetric detection of glucose using a simple paper-based analytical device. A linear correlation between gray intensity (GI) and glucose concentration (C), GI = − 10.7C + 161.8 is achieved with a correlation coefficient of 0.991, indicating the potential for semi-quantitative analysis of real sample in the field.

Melt flow rate (MFR) and vinyl acetate content (VAC) are the target parameters for quality control of poly(ethylene vinyl acetate) (EVA) pellets in production processes. Standard test methods for these two properties are too time consuming to meet the actual instant needs in industry. In order to solve this problem, an online near-infrared spectroscopy (NIR) system was integrated in this study to determine the MFR and VAC of EVA pellets in process. When collecting spectra, the difference of sample loading density and optical path will cause noise and decrease the spectral and prediction precision of quantitative models of the MFR and VAC. Although routine spectral pre-treatment methods, including the first order (1st) derivative and multiplicative scatter correction (MSC), are effective in reducing noise, the standard error of prediction (SEP) values of partial least squares (PLS) models of MFR and VAC using the pretreated spectra are still much larger than the reproducibility requirement of standard methods. The key aim of this present study is to explore a novel method based on angle transform to improve the online models. Before establishing models, the original spectra are transformed to angular spectra that reflect the composition information of the sample and are not influenced by the spectral intensity. This method can effectively reduce the severe noise and improve the performance of the models. The SEPs of PLS models of the MFR and VAC using angular spectra are 0.08 and 0.21, respectively. These two values are lower than the reproducibility requirement of standard test methods for the MFR, 0.1 and VAC, 0.3. A new online method of NIR spectroscopy combined with PLS using angular spectra has been successfully established to simultaneously determine the chemical and physical properties of EVA pellets. This research solves a tough technical problem existing in online NIR analysis of pellet samples carried by conveyor belts or pipelines with diffuse reflectance mode.

The development of wearable healthcare electronics has created higher demands on both the sensitivity and stretchability of flexible sensors. As it is generally difficult to obtain a trade-off between sensitivity and stretchability, the fabrication of strain sensors with both a wide operating range (≥100%) and high sensitivity (GF ≥ 100) remains a great challenge. Here, we propose for the first time a strategy based on the consolidation of two basic but seemingly paradoxical sensing mechanisms, i.e., slippage and crack propagation mechanisms, to greatly enhance the sensitivity of stretchable strain sensors. Based on stretchable polyurethane (PU) fibers, which can be easily woven into conventional fabrics to produce wearable devices, we present a multilayer sensing structured fiber sensor fabricated by layer-by-layer self-assembly of sliver nanowire (AgNW)/waterborne polyurethane (WPU) layers and MXene layers. The sensor simultaneously exhibits an ultrahigh sensitivity (GF = 1.6 × 107) and a wide operating range (up to 100%), as well as great reliability and stability (1000 cycles) and fast response (344 ms) and relaxation (344 ms). Moreover, smart fabrics were fabricated by integrating fiber strain sensors into different clothes and a prototype body posture monitoring, analysis, and correction system was presented for healthcare applications. Our work not only breaks down the technological wall between high sensitivity and high stretchability of strain sensors, but also shows the great potential applications of wearable, comfortable, and non-intrusive electronics for real-time health monitoring.

Efficient utilization of abundant solar energy for steam generation is an attractive, renewable, and environment-friendly technology for seawater desalination and wastewater purification, enabling solutions to address the global long-standing water scarcity issues. However, the low energy efficiency, high cost and complex systems with multiple components of state-of-the-art technologies hindered their practical applications. Herein, we report the first example of three-dimensional (3D) MXene architecture (3DMA)-based solar steam generators via a facile two-step dip coating process without any annealing or high temperature carbonization. The 3DMAs prepared by a cost-effective, scalable, simple fabrication method show effective broadband solar absorption (∼98%) and excellent solar thermal conversion ability based on 2D to 3D morphological transformation of MXenes, making good use of intrinsic theoretical photothermal performance of MXenes. The particularly hydrophilic nature of MXenes and the macroporous structure of melamine foam allow continuous water supply to 3DMAs owing to their strong capillary effect. As a result, the 3DMAs achieve water evaporation rates of 1.41 and 7.49 kg m−2 h−1 under solar illumination of 1 sun and 5 sun with a superb solar steam efficiency of up to 88.7% and 94.2%, respectively. This scalable 3DMA can be used to produce clean water from both seawater and wastewater with rejections close to 100% for organic dyes and metal ions. This work creates a platform to develop novel composite materials for solar-driven seawater desalination and wastewater purification via opening a new window for the utilization of MXenes as photothermal agents in practical applications.

Mg2Ni0.7M0.3 (M=Al, Mn and Ti) alloys were prepared by solid phase sintering process. The phases and microstructure of the alloys were systematically characterized by XRD, SEM and STEM. It was found that Mg3MNi2 intermetallic compounds formed in Mg2Ni0.7M0.3 alloys and coexisted with Mg and Mg2Ni, and that radius of M atoms closer to that of Mg atom was more beneficial to the formation of Mg3MNi2. The hydrogen storage properties and corrosion resistance of Mg2Ni0.7M0.3 alloys were investigated through Sievert and Tafel methods. Mg2Ni0.7M0.3 alloys exhibited remarkably improved hydrogen absorption and desorption properties. Significantly reduced apparent dehydriding activation energy values of −46.12, −59.16 and −73.15 kJ/mol were achieved for Mg2Ni0.7Al0.3, Mg2Ni0.7Mn0.3 and Mg2Ni0.7Ti0.3 alloys, respectively. The corrosion potential of Mg2Ni0.7M0.3 alloys shifted to the positive position compared with Mg2Ni alloy, e.g. there was a corrosion potential difference of 0.110 V between Mg2Ni0.7Al0.3 alloy (−0.529 V) and Mg2Ni (−0.639 V), showing improved anti-corrosion properties by the addition of Al, Mn and Ti.

Uniform arrays of three shapes (gauss, hat, and peak) of GaAs microlenses (MLs) by wet-etching are demonstrated, ∼200 nm spatial isolation of epitaxial single QDs embedded (λ: 890–990 nm) and broadband (Δλ∼80 nm) enhancement of their quantum light extraction are obtained, which is also suitable for telecom-band epitaxial QDs. Combined with the bottom distributed Bragg reflector, the hat-shaped ML forms a cavity and achieves the best enhancement: extraction efficiency of 26%, Purcell factor of 2 and single-photon count rate of 7×106 counts per second at the first lens; while the gauss-shaped ML shows a broader band (e.g., longer λ) enhancement. In the MLs, single QDs with featured exciton emissions are observed, whose time correlations prove single-photon emission with multi-photon probability g(2)(0)=0.02; some QDs show both biexciton XX and exciton X emissions and exhibit a perfect cascade feature. This work could pave a step towards a scalable array of QD single-photon sources and the application of QD photon-pair emission for entanglement experiments.

In order to study the feasibility of the Magnetic Barkhausen Noise (MBN) technique for low cycle fatigue damage non-destructive testing (NDT) of X4CrNiCuMo steel for nuclear power turbine blades, the axial low cycle fatigue tests are carried out on X4CrNiCuMo steel specimens for turbine blades. The relationships between the MBN signal and microstructure, fatigue damage are studied by means of the MBN technique, transmission electron microscope (TEM) and metallographic microscope. The results showed that the MBN signal is very sensitive to low cycle fatigue damage. The MBN signal exhibits three main stages during the fatigue life. At the beginning of the test the MBN signal decreased rapidly, then it increased continuously and finally the signal suddenly dropped and then increased before failure. These successive stages can be associated to the typical stages of the low cycle fatigue life of metals such as cyclic hardening, cyclic softening and surface crack initiation and propagation. Thus, the MBN technique used in this paper can be an important reference for the fatigue damage assessment of turbine blades.

Wearable strain sensors with high sensitivity and linear resistance signal response to strain are urgently demanded for human–machine interface, which can be tuned by introducing uneven surface mechanics distribution onto fiber surfaces via structural heterogeneity for fibrous elastomer fiber mat sensors. Yet it is still of great challenge to build micro- or nano-scale heterogeneous structures on fiber surfaces in a facile and scalable way without using templates. Herein, we report a plastic nanosphere-decorated elastomer fiber mat strain sensor with a zoned surface strain energy release characteristic, designed based on analysis of material match and structural mechanics. Surface mechanics analysis confirms that the as-designed sensor shows a controllable strain energy release area, significantly improving sensing stability thanks to effective restriction of micro-crack propagation in conductive pathways. In particular, fibrous mat sensor with high-density nanospheres shows very low fluctuation in strain sensitivity variation (±0.05 for strain ≤ 30 %), i.e., good linearity in the resistance response to strain, while that for the control sensor is ± 10.0 for strain ≤ 16 %. Such a fiber mat strain sensor can not only be applied for real-time sensing of object deformations for human–machine interface and intelligent control, but also in hydrophobic porous elastomeric packaging materials and triboelectric devices.

High-temperature particles produced from metallurgy, building materials, and chemical industry are mostly characterized by wide variations in temperature and flow rate, and the waste heat recovery processes from these particles are essentially unsteady. The heat transfer characteristics in a gas–solid countercurrent moving bed under periodic variation of inlet particle flow rate and temperature are investigated. The wide variation of inlet particle flow rate and temperature causes wide variation in input heat capacity ratio. However, their effects are different. The inlet particle temperature variation has slight effects on the instant outlet particle temperature and heat recovery efficiency, but great on that of air for the simulated cases. The variation amplitude of outlet air temperature is up to 431.41 K under the wide temperature variation of 600 K and long duration of 2.5τp (τp is the particle residence time). Improving technique should be adopted to maintain the temperature level of outlet air under wide temperature variation according to the utilization of the recovered heat. Meanwhile, the wide variation of flow rate affects the instant outlet particle and air temperatures. The variation amplitudes of outlet particle and air temperature are 88.90 K and 203.35 K, respectively. Furthermore, instant heat recovery efficiency decreases 9.6% under the wide flow rate variation that ranges from 46.58 to 19.96 t/h and long duration of 2.5τp. Varying the flow rate of air flow with an accordance variation range and duration of particle may be an efficient way if the instant heat recovery efficiency and temperature level of outlet air are requested.

The oil/water (o/w) separation is a global challenge because of the increasing water contamination by oil spill accidents, and oil-containing wastewater produced by food, textile, and petrochemical industries. In this study, we have developed bacterial cellulose (BC) based superhydrophilic/underwater superoleophobic (SUS) membrane for o/w separation. The membrane was designed through a facile method by blending BC nanofibers with silica microparticles (SiO2-MPs), which was further modified by bio-inspired polydopamine (PDA) coatings. The composite membrane exhibited SiO2-MPs dependent o/w separation with a high separation efficiency of >99.9 % and a high flux rate of ∼10,660 Lm−2 h-1 while applying a small negative pressure (0.3−0.5 bar). The membrane with different content of SiO2-MPs also showed the potential to separate oil-in-water emulsion with the highest oil rejection of 98.2 % and the highest flux rate of ∼1250 Lm−2 h-1 on an ultra-low pressure

We proposed a precise calibration process of Al 0.9Ga0.1As/GaAs DBR micropillar cavity to match the single InAs/GaAs quantum dot (QD) exciton emission and achieve cavity mode resonance and a great enhancement of QD photoluminescence (PL) intensity. Light-matter interaction of single QD in DBR micropillar cavity (Q ∼ 3800) under weak coupling regime was investigated by temperature-tuned PL spectra; a pronounced enhancement (14.6-fold) of QD exciton emission was observed on resonance. The second-order autocorrelation measurement shows g(2)(0)=0.070, and the estimated net count rate before the first objective lens reaches 1.6×107 counts/s under continuous wave excitation, indicating highly pure single-photon emission at high count rates.

Ni-rich cathode material is one of the most promising material for Li-ion batteries (LIBs) in portable power and electric vehicles. However, how to recycle waste LIBs cathode materials is very important for environmental protection and resource utilization. LiNi0.6Co0.2Mn0.2O2 cathode materials were prepared by sol–gel combustion method Using waste LIBs cathode materials as raw materials. The effect of different gels on the crystal structure and morphology of LiNi0.6Co0.2Mn0.2O2 were studied by X-ray diffraction and scanning electron macroscopy. The electrochemical properties were investigated by charge–discharge testing, cyclic voltammetry and electrochemical impedance spectroscopy. The results showed that the samples contained some residual C and primary crystals have been formed during combustion stage. When glucose was used as gel regent, the sample has the good electrochemical properties with the initial discharge capacity of 176.9 mAh g−1, initial coulombic efficiency of 87.0% and discharge capacity retention rate of 95.8% after 50 cycles at 0.2 C rate. The results showed that the less the cation mixing, the more complete of hexagonal crystal structure, which induced the decrease of impedance resistance and good reversibility of redox reaction.

The Ti3SiC2-TiB2-TiC three-phase ceramics are prepared by Spark Plasma Sintering (SPS) method with Self-propagating High-temperature Synthesis (SHS) using Ti, Si, C andB4C powders. The characterization of sintering product’s image and structure is analyzed by XRD and SEM. Most of TiB2’s images are angular cuboid or short bar-shaped and most of TiC phase’s images are irregular spherical particles which are evenly embedded in Ti3SiC2 substrate and have a good combination interface with Ti3SiC2. In the composite ceramic SPS sintering process, sinter sample’s displacement along Z-axis goes through three stages of falling, balance and rising along with the change of heating temperature, which reflects the sample’s change rule between heated expansion force and pressure. Finally its machining performance is analyzed by wire cutting method and machining method. The Ti3SiC2-TiC-TiB2 block composite ceramic proves to have a good machining performance.

Effects of aspect ratio of multi-wall carbon nanotubes (MWCNTs) on the dispersion of MWCNTs in ethylene-α-octene block copolymer (OBC) and the properties of OBC/MWCNTs nanocomposites were studied, and two series of MWCNTs with different aspect ratios based on the same length and the same diameter were considered. Scanning electron microscope (SEM) and transmission electron microscope (TEM) results show that small and large agglomerates induced by intra- and inter-entanglement of MWCNTs are present for MWCNTs with high aspect ratio having smaller diameter and larger length, respectively. Rheological, electrical and tensile properties of OBC/MWCNTs nanocomposites are related to the aspect ratio and dispersion of MWCNTs. The formation of agglomerates, especially large agglomerates, influence the network perfection, weakening the contribution of MWCNTs to the rheology and electrical properties. The inter-entanglement shows less negative effect on the enhancement for the modulus and strength of OBC nanocomposites, and intra-entanglement of MWCNTs shows discounted enhancing properties. The aspect ratios of MWCNTs related to not only the length but also the diameter play the dominant role on the dispersion in polymers and the properties of polymer nanocomposites.

High-level moisture removal is often encountered in the pressure swing adsorption (PSA) for air prepurification. The effects of high-concentration water vapor adsorption on the heat and mass transport characteristics of PSA should be described in detail for further design and optimization of air prepurification processes. In this work, a mathematical model of an alumina/13X-layered two-bed Skarstrom-type PSA cycle for the removal of high-level moisture along with CO2 from air is established to study the heat and mass transport characteristics during the process. The maximum increase and decrease in temperature are related to the water vapor concentration in the feed air, and two simplified formulas are proposed to estimate their magnitudes. The mass transport characteristics, especially the penetration depths of the two impurities, are examined under different inlet temperatures, adsorption pressures, purge-to-adsorption flow rate ratios, inlet flow rates, and cycle times. A relation between the penetrati...

Multi-walled carbon nanotubes (MWCNTs) were easily dispersed at the interface of polyvinylidene difluoride (PVDF) and ethylene-α-octene block copolymer (OBC) blend by melt compounding and the nanocomposites exhibited enhanced dielectric performance, electromagnetic interference shielding effectiveness (EMI SE) and balanced mechanical performance. Through the simple, efficient and scalable interfacial strategy to disperse MWCNTs at the interface of PVDF and OBC phases, the accumulation of charge carriers at the interfaces and strong interfacial polarization effect can be achieved. At low frequency, PVDF/OBC/MWNCT nanocomposite exhibits high dielectric permittivity (753.8) and low dielectric loss tangent (0.8), offering great potential in energy storage applications. Simultaneously, in X-band range, PVDF/OBC/MWNCT nanocomposite shows high EMI SE of around 34 dB which is higher than the industrial requirement when the content of MWCNTs is as low as 2.7 vol.%. This study provides possibilities to realize high-performance polymer nanocomposites via the particular interfacial structure through one-step melt processing.

Continuous monitoring of physical signals such as stress and strain plays a crucial role in Internet of Thing and artificial intelligence, thus flexible mechanical sensors gain increasing attention due to their enormous application potential in wearable electronics, soft robots, human-machine interfaces, etc. Recently, significant progress has been made in mechanical sensors for trading off high sensitivity and wide range for low dimensional strain/force sensors, yet it is still of significant challenge to discriminate complicated three-dimensional (3D) mechanical signals in practical applications. Herein, a novel wearable film sensor capable of sensing multi-directional mechanical stimuli is developed by coating MXene onto low-entropy structured piezoelectric poly(vinylene fluoride-trifluoroethylene) (PVDF-TrFE) mat composed of aligned nanofibers. The resultant functional fiber mats give rise to an anisotropic in-plane conductive network for 2D in-plane strain sensing, and oriented ferroelectric crystals in nanofibers with piezoelectricity allow for out-of-plane dynamic pressure detection. Besides, the all-in-one flexible anisotropic sensor shows linear sensing properties and high sensitivities both in the plane strain and out of the plane pressure due to piezoresistive and piezoelectric mechanisms, respectively. Such sensors can effectively distinguish multi-directional mechanical stimuli for potential applications in human machine interfaces, healthcare, entertainment and other systems.

Fixed-bed sorption technology is a promising option for separating CO2 from flue gas, and potassium-based Al2O3 (K2CO3/Al2O3) is a potential sorbent in the presence of H2O. This paper studies the stepwise reaction mechanism of CO2/H2O sorption on K2CO3/Al2O3, and the expressions of sorption equilibrium and kinetics are proposed and verified by experimental data. A comprehensive set of mathematical models of separation and recovery CO2 from wet flue gas in a fixed bed of K2CO3/Al2O3 is established. The CO2 separation and recovery process from wet flue gas in the fixed bed are numerically studied. Detailed results of H2O/CO2 sorption and desorption in the fixed bed during pressure/vacuum swing cycles are revealed, and the optimum operating parameters are suggested. Results show that carbon dioxide recovery can be further enhanced using a vacuum temperature swing adsorption (VTSA) process or by adding a pre-wetting step before sorption process.

Fluorenylmethyloxycarbonyl (Fmoc)-conjugated amino acids, especially Fmoc-phenylalanine (Fmoc-F), are promising antibacterial agents with self-assembly capabilities. However, they possess weak antibacterial activities against gram-negative bacteria, which restricts their wide range of biomedical applications. In this study, Fmoc-F-based self-assembled supramolecular hydrogels were fabricated through a facile incorporation of silver ions. The prepared supramolecular hydrogels showed antibacterial properties (>98.0%) against both Staphylococcus aureus (S. aureus, gram-positive) and Escherichia coli (E. coli, gram-negative) bacteria. Moreover, the hydrogels were biocompatible, and the cell viability against mouse fibroblast cells was more than 85.0%. These results indicate that the Fmoc-F@Ag hydrogel can be used effectively for antibacterial applications.

A new hot-dip galvanizing method was employed on hot-rolled low carbon steel. The effects of Al contents on microstructure, micro-hardness and corrosion resistance of Zn-Al alloy coatings were systematically investigated. Phase composition, microstructure and element distribution in Zn-Al alloy coatings were analyzed using X-ray diffraction (XRD) and electron probe micro analysis (EPMA), respectively. It is found that Al content (0. 6–6. 0 wt. %) in galvanizing zinc affects surface quality and adhesion between coatings and matrix in the newly developed method. In addition, with increasing Al content, micro-hardness significantly increased due to the increase in Zn-Al eutectoid phases. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) also revealed that increase in Al plays a noticeable role in improving the corrosion resistance of Zn-Al alloy coatings.

Supercritical carbon dioxide (SC-CO2) dyeing is an ecological waterless dyeing method without any dyeing auxiliaries and waste water discharge. In this paper, we introduce continuous dyeing processes of zipper tape in SC-CO2 while recycling the gas simultaneously. Compared to water dyeing, this new processes could reduce CO2 gas consumption and increase production efficiency, and lead to 20% cost decrease. The dyed products also present excellent color fastness to fading, staining, drying, and wetting, which are all rated at a grade of 4–5. The dyed zipper tapes show excellent shade consistency by different dyeing autoclaves, proving that this continuous processes is suitable for the rapid and diverse color change of smaller lots.