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A visible-light driven solid-state NIR fluorescent bistable molecular switch was constructed by coupling bulky tetraphenylethylene, photochromic diarylethene and NIR emissive terrylene diimide. Multi-level optical storage was demonstrated based on its film.

Schematic diagram of dual treatment of bacterial infection.

Lacquer wood (LW) goes through one-step and two-step H3PO4 activation process to prepare activated carbons (ACs) at different temperature, and its performance was evaluated by testing CV, EIS, GCD and cycling respect to an electrode material in supercapacitors. The performance of lacquer wood activated carbon prepared by different activation methods and temperature (300, 400, 500, 600, 700, and 800 °C) was studied, and the influence on its electrochemical properties provides valuable guidance for the high-efficient energy utilization of lacquer wood. The results showed that the AC generated via one-step activation process at 400 °C demonstrate excellent specific surface area (SBET 1609.09 m2/g) than those from two-step activation method. Besides, the biomass-derived ACs presented overall better electrochemistry characteristic than those from charcoal-derived ACs. The largest specific capacitance (354 F/g) was obtained in the ACs-based electrodes which was generated from one-step activation process (activated at 600 °C). After 10000 cycles, its capacity retention reached 95.3%, which provides a meaningful guidance into the application of energy storage supercapacitors. This study proves that the LW derived ACs are promising electrodes of the high-performance supercapacitors, which is beneficial for value-added and industrial supercapacitors application of lacquer wood ACs.

Fallen leaves of landscape trees, as an emerging biomass waste, were valorized using conventional hydrothermal carbonization (HC) and microwave‐assisted hydrothermal carbonization (MHC) pretreatments, and were comparatively characterized for physicochemical properties and thermal degradation kinetics. The results show that MHC is superior to conventional HC operation, because at 200℃, the MHC process not only gives a higher hydrochar yield (45.09 vs. 39.47 wt%) with significantly reduced energy consumption (0.63 vs. 2.74 MJ g−1), but also is more effective in removing K and Si. For isoconversional kinetic analysis, the FWO method provides better results than the KAS method as the latter failed to fit the tree leaves sample (R2 400℃) showed that the hydrochar obtained from the MHC process has a lower average activation energy of ~190 MJ kg−1 than the conventional HC process (~260 MJ kg−1). This study reveals the potential for valorization of the landscape tree wastes via the MHC process.

Hen egg white lysozyme (HEWL) is frequently applied as a model protein for research on protein folding, unfolding, and fibrillization identified by featured fluorescent probes. Here, a series of hydrophilic, pH-sensitive tetraarylethene (TAE)-type AIEgens are synthesized via a geminal cross-coupling (GCC) reaction and evaluated for their capabilities of fluorescence sensing and super-resolution localization imaging of HEWL fibrils. With superior optical and sensing properties, the selected TAE-type AIEgen probe is weakly emissive in aqueous media, without dependence on the pH value and buffer concentration, but exhibits "turn-on" fluorescence upon interaction with HEWL amyloid fibrils in a spontaneous and reversible way that just meets the requirement of fluorescence random switching for super-resolution imaging. The selected probe has the strongest fluorescence response to HEWL amyloid fibrils exhibiting a limit of detection of 0.59 nmol/L and enables super-resolution fluorescence imaging of amyloid aggregates with a high resolution of 40 nm.

The grave threat posed by food hazards to food security and human health has increased the urgency of rapid and sensitive detection. Enzyme-mimic immune detection, particularly nanozyme-activated food immunosensors (NAFI), shows distinct specificity and catalytic properties, advancing food safety supervision. However, knowledge of the fundamental principles and functionalities of NAFI is still limited. Based on tracking the timeline of the independent evolution and combination of immunosensors and nanozymes, we first provide a systemic view to describe the trends of NAFI. Moreover, the underlying catalytic mechanisms are discussed according to classification in this review, including metal-based, carbon-based, and metal-organic framework-based nanozymes. In particular, significant attention is focused on the fundamental function of nanozyme receptors in food immunosensors, including the connection between nanozymes and bio-affinity ligands (one pot and two steps), signal modulation and amplification, and various signal outputs (typical and novel modes), which are crucial for gaining the best performance and further innovation. Finally, based on representative applications of nanozymes to detect food hazards, the main challenges in the development of NAFI are summarized, and future research directions for this highly prospective frontier are envisioned.

Protein misfolding and denaturation, represented by amyloid fibrillation, are associated with many diseases. However, as a general chemical biological process, the dynamic structure information on amyloid fibrillation has not been demonstrated categorically. Herein, hen egg white lysozyme (HEWL) was used as the model protein of interest to realize in situ nanoscale imaging of protein fibrillation process using the fluorophores with aggregation-induced emission (AIE) activity. The AIE-active fluorophores exhibit the reversible capability of association and dissociation with β-sheet structure and thus dynamic binding-induced emission, which causes the spontaneous switching of fluorescence. The entire HEWL denaturation process induced by sodium dodecyl sulfate (SDS) at ambient conditions was demonstrated in detail by using two AIE-active fluorophores (TPE-NaSO3 and PD-BZ-OH) through reversible electrostatic interaction and specific labeling between AIE probes and β-sheet structures of amyloid fibrils, respectively. The results indicate that PD-BZ-OH is more specific AIE probe for amyloid fibrils than TPE-NaSO3. In comparison, the SEM and TEM results show the same denaturation process of protein fibrillation induced by SDS at different concentrations. The static super-resolution imaging of amyloid fibrils is performed with a resolution of 35 nm using PD-BZ-OH aqueous solution without additional auxiliary conditions. The dynamic evolution process of HEWL amyloid fibrillation is in situ visualized through super-resolution fluorescent microscopy with nanoscale resolution. Both static and dynamic super-resolution imaging of amyloid fibrillation provides detailed nanoscale structure information exceeding 50 nm resolution, which is of great significance in the exploration of amyloid fibrillation and related diseases.

Photoswitchable fluorescent diarylethenes are promisingly widely applied in the fields of optical memory, all-optical transistors, bioimaging, and super-resolution imaging, and so on. However, they face the problems of fluorescence quenching in an aggregated/solid state, the inadequate fluorescence ON/OFF switching ratio, and the necessity of UV-light irradiation. Herein, we report a novel kind of high-performance diarylethenes with aggregated-induced emission (AIE) by conjugating two diarylethene groups on one AIE-gen (i.e., TPE-2DTE (blue-green fluorescent) and OTPE-2DTE (orange fluorescence)). Their open forms show enhanced fluorescence in the aggregated and solid states. The closed form of TPE-2DTE/OTPE-2DTE was effectively generated upon short-wavelength visible-light (400 nm-450 nm) irradiation, whose fluorescence was dramatically quenched by intra- and inter-molecular energy transfer. Remarkably, 405 nm purple irradiation gives fluorescence ON/OFF ratios of 1196:1 and 1983:1 for TPE-2DTE and OTPE-2DTE, respectively. The reverse process can be accomplished after another longer wavelength irradiation such as 621 nm and shows considerable fatigue resistance. Taking advantage of superior photoswitching properties under visible-light irradiation, TPE-2DTE and OTPE-2DTE were used for super-resolution imaging with a high resolution of sub 50 nm. This work offers guidance to design bright-emitting and high-performance visible-light-controlled diarylethene photoswitches for practical applications.

To achieve an effective deconstruction for preparation of xylooligosaccharides (XOS) and lignin nanoparticles (LNPs) from Eucommia ulmoides, a synergistic pretreatment was successfully developed. Herein, the hemicelluloses were preferentially dissociated in acetic acid-catalyzed hydrothermal pretreatment (HTP) for preparation of XOS, and the hydrothermally-pretreated substrate was then subjected to deep eutectic solvents (DES) delignification for fabrication of LNPs. Results showed that the optimal yield (33.88% based on xylan) of XOS is obtained under the given HTP condition (170 °C, 0.5 h). NMR characterization showed that the linkages of lignin were mainly composed of β-O-4, β-β, β-5, etc. Besides, GPC analysis showed that the molecular weight of DES lignin fractions was lower (1130-1200 g/mol) than those of corresponding parent lignin fractions (8500-9620 g/mol). Further TEM characterization indicated that the optimal LNPs fraction has a narrow size distribution and the corresponding size is ranged from 60 to 110 nm. In short, the synergistic pretreatment could be used as a green and cost-effective approach for the development of bio-based chemicals and biomaterials from Eucommia ulmoides biomass.

Unprecedented dual aggregation-induced emission (AIE) behavior based on a steric-hindrance photochromic system is presented, with incorporation one or two bulky aryl groups, resulting in different flexibleness. The dual AIE behavior of open and closed isomers can be explained by restriction of intramolecular rotation (RIR), restriction of intramolecular vibration (RIV), and intermolecular stacking. The large bulky benzothiophene causes restricted rotation, enhancing the emission of open form in solution and weak π-π molecular packing, thereby efficiently enhancing the luminescence performance in the solid state. With incorporation of two large bulky benzothiophene groups, BBTE possesses the most outstanding AIE activity, undergoing highly efficient and reversible off-to-on fluorescence in film upon alternating UV and visible light irradiation along with excellent fatigue resistance. The off-to-on fluorescent photoswitch is successfully established in super resolution imaging.

Typical cross-linked polymer networks have rubbery elasticity and do not exhibit thermoplasticity such as linear polymers. However, thermodynamically cross-linked polymer networks exhibit certain t...

Microbial fuels cells (MFCs) have been applied for the degradation of pyroligneous liquor (PL) derived from apple tree branches, at different concentrations. The substrate removal, electrochemical properties, and microbial community characteristics were analysed to evaluate the performance of MFCs. Maximum current density (1.94 A/m2), coulombic efficiency (28%), and phenol removal rate (84%) were achieved with MFCs fed with PL at the optimal concentration of 1 g chemical oxygen demand (COD)/L. The polarisation test, cyclic voltammetry, and electrochemical impedance of the electrode redox reaction further explained how the addition of PL could stimulate formation of the electrochemically active biofilm, at the optimal concentration of 1 g COD/L. The microbial community of the anodic biofilm demonstrated that MFCs fed with 1 g COD/L had the highest relative abundance of the typical electrogenic bacteria Geobacter (33%), followed by Sphaerochaeta (6%) and Clostridium (4%). The results revealed that syntrophic interaction of these functional microorganisms contributed significantly to the PL degradation and electrical current generation.

The flexible binderless films composed of cobalt selenide grains attached on carbon nanofibers (denoted as CoSe2/CNFs) are prepared by electrospinning to enhance the electronic conductivity, Na-ions diffusion and alleviate volume variation during charge/discharge process for high performance sodium-ion batteries (SIBs). The binderless and flexible CoSe2/CNFs electrode can obtain a high reversible capacity of 430 mAh g−1 after 400 cycles at a current density of 200 mA g−1, an exceptional rate capability of 224 mAh g−1 at 15 A g−1, even a capacity of 370 mAh g−1 at 2 A g−1 after 1000 cycles. The superior electrochemical performance can be ascribed to the synergistic effects of the homogeneous distribution of CoSe2 grains attached to the carbon nanofibers and the high electronic conductivity framework of 3D interconnecting carbon nanofibers, which can alleviate the volume variation during charge-discharge process and sustain the high electrical conductivity and fast Na-ions diffusion throughout the electrode. This binderless flexible CoSe2/CNFs nanocomposite electrode may hold great application promising for high cycling performance SIBs.

The effect of hydrogen on the premixed combustion of low calorific value gas in cylinder was carried out. The engine bench test system was built, and the effects of hydrogen on the pressure in cylinder, the characterization parameters of flame stability, flame shape, combustion cycle variation, flame surface structure and development were studied. The experimental results show that adding hydrogen to low calorific value gas fuels can increase laminar flame propagation rate, increase heat release rate, improve engine volumetric efficiency and reduce engine cycle variation. With the increase of hydrogen fraction, the maximum cylinder pressure of the engine rises, the corresponding crankshaft angle moves forward, and the flame development period and the rapid combustion period of the engine working cycle are reduced. The flame propagation rate of hydrogen blended low calorific value gas is larger, which enhances the strength of the vortex blob in cylinder to some extent. The increase of hydrogen fraction in mixture increases the flame propagation velocity, and enhances the effect of the combustion process on vortex intensity in cylinder, which increasing the effect of vortex blob on the flame surface structure. With the increase of hydrogen fraction, the vortices of the flow field in the cylinder increase, the time of which the flame surface reaches the same fold is in advance, and the flame development period is shortened.

Tetraphenylethylene (TPE) derivatives are typical aggregation-induced emission (AIE) molecules, which have been widely investigated and applicated. The Rathore’s procedures and McMurry reaction are the two frequently used methods for synthesizing the TPE derivatives. The complex processes and low tolerance of active function groups make the TPE with limited structures and properties in some degree. Very recently, a novel strategy, named geminal cross coupling (GCC) reaction, is developed for designing and synthesizing various topological small molecules and polymers with rich optical properties beyond simple TPE compounds, and becomes a powerful synthesis method to AIE materials. This review overviews the current progresses of AIE molecules and polymers prepared by GCC as well as their applications. We believe that GCC reaction will have a bright future in the development of the next generation of tetraarylethylene (TAE)-kind AIE materials.

The commercial production of advanced fuels based on bio-oil gasification could be promising because the cost-effective transport of bio-oil could promote large-scale implementation of this biomass technology. So far there has been no specialized review of bio-oil gasification processes, including non-catalytic partial oxidation of bio-oil for syngas production and steam gasification of bio-oil for hydrogen production. A detailed and comprehensive review of gasification of bio-oil for gas production is presented in this paper. The background and significance of bio-oil research, the characteristics of bio-oil suitable for gasification, bio-oil gasification theory, types and configurations of bio-oil gasifiers, the quality of the product gas, parameter effects, and economic evaluation of bio-oil gasification are discussed, and finally a summary and future outlook are also delivered. Particular emphasis is placed on the discussion regarding the atomization of bio-oil, entrained flow gasifiers and their advantages, gas composition and the economic feasibility of production of advanced fuels via bio-oil gasification. Challenges for the future are identified as follows: (1) making full use of the experience accumulated in the area of petroleum refining; (2) practical demonstration of bio-oil gasification on a scale of 500 to 1000 kg bio-oil per hour; (3) the development of mathematical models for bio-oil gasification systems; and (4) development of suitable catalysts and profoundly understanding the catalyst deactivation mechanism at different stages for steam gasification of bio-oil.

The molecular diversity of aggregation-induced emission remains a challenge due to the limitation of conventional synthesis methods. Here, a series of novel neutral and cationic conjugated polymers composed of various ratios of tetraarylethylene (TAE) containing a bridged oxygen (O) and fluorene (F) units is designed and synthesized via the geminal cross-coupling (GCC) of 1,1-dibromoolefins. The incorporation of TAE segments into the conjugated backbone of polyfluorene produces pronounced aggregation-induced ratiometric fluorescence, i.e., aggregation-induced emission (AIE) at 520-600 nm and grows synergistically with aggregations-caused quenching (ACQ) at 400-450 nm. The content of fluorene unit in the polymer backbones determines the intensity of the initial fluorescence in the blue light region. The huge distinction (about 150 nm) in dual emission wavelengths caused by the environment change makes these conjugated polyelectrolytes particularly suitable for ratiometric fluorescence sensing. Based on electrostatic interaction mechanism, the gradual addition of heparin into the cationic conjugated polymers aqueous solutions can induce dual-color fluorescence changes with a detection limit of 9 × 10

Eucommia ulmoides Oliver (EUO) wood goes through hydrothermal pretreatment (HTP) followed by chemical activation to produce activated carbons (ACs), which are then applied as electrode materials for supercapacitors application. The porous structure, surface chemistry and electrochemical characteristics of the ACs have been investigated in detail. The specific surface area (SBET) of the ACs enlarges from 1272.38 to 1534.06 m2 g−1 following the increase of HTP temperature from 150 to 170 °C, and then decreases to 1284.69 m2 g−1 when HTP temperature increased further to 200 °C, indicating that HTP temperature of 170 °C is the turning point on SBET of the ACs. Moreover, the ACs obtained at HTP temperature of 170 °C are observed with highest mesopore pore volume (1.66 cm3 g−1) and mesopore pore diameter (6.02 nm). Additionally, the Raman and FTIR spectrum of the ACs also prove that HTP temperature of 170 °C can enhance the graphitization during the activation process, indicated with low ID/IG ratio (0.74) and vibrational amplitude. These results reveal that the HTP effectively influences the porous structure and surface chemistry characteristics of the ACs by manipulating substrate structure of the ACs precursor. The characterization of the porous structure and surface chemistry illustrate that the activated carbon produced via HTP at 170 °C for 1 h exhibited high specific surface area (1456.69 m2 g−1) along with large percentage of mesopores pore volume (93%), which then result in high specific capacitance of 185 Fg−1 and long-term cycling performance. This study prove that the EUO derived ACs are promising materials for supercapacitor application and can expand EUO wood for feasible application in supercapacitors.

Among various photochromic compounds, diarylethenes (DAEs) have been widely studied and applied due to their excellent thermal bistability and fatigue resistance. Most researches are focused on the properties and applications of DAEs in solution. However, they meet the problem of fluorescence quenching at high concentration or at solid state which limits their performance in the practical applications. Fortunately, the DAE based photochromic aggregation-induced emission (AIE) materials do well in addressing this problem. This work here reviews the current research progress on the structures, properties and applications of the DAE based photochromic AIE materials and points out some existing problems so as to promote subsequent development of this field in the future.

TiO2-B has received increasing interest as a possible anode for lithium-ion batteries, but its properties are restricted by the intrinsically low electronic conductivity. Herein, we first demonstrate that phosphorus doping can be an efficient approach to boost the pseudocapacitive properties of TiO2-B nanowire arrays. The phosphorus doping not only promotes electronic conductivity of TiO2-B nanowire arrays by modifying their electronic structure, but also significantly enhances the electrochemical surface reactivity. Density functional theory calculations further reveal that the phosphorus doping could improve the surface lithium affinity of TiO2-B nanowire arrays. Consequently the phosphorus-doped TiO2-B nanowire arrays simultaneously exhibit high reversible capacity (350.9 mAh g−1), remarkable rate capability (142.6 mAh g−1 at 30 C), and impressive cyclability (approximately 80% capacity retention efficiency over 3000 continuous cycles at 10 C), holding promise in high-energy and high-power lithium-ion batteries application.

This paper presents the results regarding the parametric optimization and characterizations on codensification of Eucommia ulmoides Oliver stem using biochar and bio-oil as additives. The results reveal that the relative importance of different parameters contributing to the pellet physical stability follows the order of: particle size > bio-oil content > biochar content > pressure > bio-oil type, and smaller particles size (0.1–0.3 mm) is critical for the formation of durable pellets. The biochar functioned as the fuel promoter and improved the higher heating value and energy density, however, caused poor physical stability by secondary size reduction during densification. The apple tree branch pyrolysis oil acted as an effective binder, improved the surface morphology and enabled strong interlocking of the particles, therefore, enhanced the physical stability. Above all, codensification of Eucommia ulmoides Oliver stem with biochar and bio oil generated pellets with excellent physical stability and moisture resistance. The pellets also showed better fuel characteristics than the Eucommia ulmoides Oliver stem pellets, and the cost is significantly lower than the char pellets. With comprehensiveness, these results can guide the future industrial implementation of codensification technology for the production of clean, sustainable, and efficient fuel with low cost.

Pure In2O3 has a high specific capacity but suffers a short cycling life when used as an anode because of the huge volume change during the lithiation and delithiation processes. To overcome this problem, here In2O3 nanoparticles (10–20 nm)/carbon fiber hybrid mat has been synthesized via a facile electrospinning process. The as-prepared mat is textile-like with considerable flexibility, and directly used as binder- and current collector-free anode for lithium-ion battery. It exhibits a good electrochemical performance with a stable capacity of 435 mA h g−1 at 100 mA g−1 after 500 cycles and a high rate performance (190 mA h g−1 at 1500 mA g−1), which are hugely enhanced compared with those of both pure In2O3 and powder In2O3@CF with binder and current collector. This work offers a promising approach to fabricate free-standing flexible anode for practical energy storage and conversion devices.