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Direct visualization of polymer crystalline structure remains challenging due to the lack of contrast across different microphases of polymers. Here we address this conundrum using an aggregation-induced emission luminogen (AIEgen) with confinement fluorescence effect, which could be used as a “built-in” sensor to label different crystalline phases. Computational simulations reveal that the confined space induces the AIEgens to take a more planar conformation, resulting in a red-shifted emission spectrum. With this property, the information of various polymer crystalline forms is converted into different fluorescence colors, which is attributed to the different spatial dimensions of the polymer amorphous layer between lamellar crystals where the AIEgens are located. Finally, polymer crystalline phases distinction, quantitative crystallinity determination, and stereocomplex crystals visualization are achieved, providing a relationship between crystalline microstructure and fluorescence signals. This work demonstrates the potential of AIE fluorescence technology in polymer science, providing a theoretical and experimental guideline for the materials processing and optimization of mechanical performance.

Natural vegetation has been proved to promote water purification in previous studies, while the relevant laws has not been excavated systematically. This research explored the relationships between vegetation cover and water quality indexes in Liaohe River Basin in China combined with self-organizing map (SOM) and geographically and temporally weighted regression (GTWR) innovatively and systematically based on the distributing heterogeneity of water quality conditions. Results showed that the central and northeast regions of the study area had serious organic and nutrient pollution, which needed targeted treatment. And SOM verified that high vegetation coverage with retention potential of organic and inorganic pollutants as well as nutrients improved water quality to some degree, while the excessive discharges of pollutants still had serious threats to nearby water environment despite the purification function of vegetation. GTWR indicated that the waterside vegetation was beneficial for dissolved oxygen increasing and contributed to the decreasing of organic pollutants and inorganic pollutants with reducibility. Natural vegetation also obsorbed nutrients like TN and TP to some degree. However, the retential potential of nitrogen and organic pollutants became not obvious when there were heavy pollution, which demonstrated that pollution sources should be controlled despite the purification function of vegetation. This study implied that natural vegetation purified water quality to some degree, while this function could not be revealed when there was too heavy pollution. These findings underscore that the pollutant discharge should be controlled though the natural vegetation in ecosystem promoted the purification of water bodies.

To further reduce the contents of phosphorus and suspended solids (SS) in the effluent, the high-rate clarifier is adopted by some wastewater treatment plants (WWTPs) to upgrade their processes. However, due to the complex phosphorus species and unclear hydraulic characteristics after the addition of the high-rate clarifier, the removal efficiencies of total phosphorus and the optimization strategies of SS removal remain unclear. The high-rate clarifiers are mainly composed of the mixing zone and the settling zone. Only the hydraulic characteristics of the mixing zone have been studied. It is necessary to focus on the hydrodynamics of the settling zone to understand the sedimentation process and pollutant removal mechanism in depth. Therefore, this study focused on the whole process of high-rate clarifier of the Wuhan Nantaizi Lake WWTP in China. The distributions of flow velocity and SS in the full-scale high-rate clarifier were simultaneously simulated by the solid-liquid two-phase whole process computational fluid dynamics (CFD) model which was established in this study. The simulated results of the developed CFD model were in good agreement with the experimental data obtained in the high-rate clarifier. The normalized standard error was less than 7.66%. The overall flow velocities in the settling tank were much smaller than that in the reaction tank. After the fluid passed through the diversion effect of the overflow wall and the under-through channel, the overall kinetic energy loss was relatively large. Meanwhile, the residence time of fluid in the settling tank was longer than that in the reaction tank. The sludge sedimentation happened at the edge of the settling tank due to the vertical angle between the plug-flow fluid and the outlet. The successful construction of the CFD model could lay the foundation for the next step of the high-rate clarifier optimization operation and research on pollutant removal.

Mesoscopic aggregate is important to transfer or even amplify the molecular information in macroscopic materials. As an important branch of aggregate science, aggregation-induced emissive luminogens (AIEgens) often show slight or even no emission in solutions but exhibit bright emission when they aggregate, which open a new avenue for the practical applications. Due to the flexible and rotor structure of AIEgens, the aggregate structure of AIEgens is highly sensitive to the surrounding microenvironment, resulting in adjustable optical properties. Fibers integrated of a multiplicity of functional components are ideal carriers to control the aggregation processes, further assembly of fibers produces large-scale fabrics with amplified functions and practical values. In this Concept article, we focus on the latest advances on the synergy between "AIE+Fiber" for the boosted performance that beyond AIE, and their applications are presented and abstracted out to stimulate new ideas for developing "AIE+Fiber" systems.

To improve the edible qualities of meatballs, various percentages of pork fat in meatballs were replaced by brown flaxseed flour (BFF) to decrease the fat contents and further optimize the fatty acid compositions. Five different meatball formulations that used 0%, 5%, 10%, 15%, and 20% of flaxseed flour additions were used in which the corresponding amounts pork fat were replaced. The proximate compositions, water activity, pH levels, colors, textures, cooking losses, fatty acid compositions, sensory properties, flavors, and oxidation stabilities of these meatballs were analyzed. Increasing the BFF addition amounts improved the protein and dietary fiber contents, pH levels, fatty acid profiles and oxidation stabilities, but decreased the fat contents, moisture levels, cooking losses, n6/n3 ratios, hardness, and lightness. The volatile flavors of meatballs with different BFF replacement levels were significantly different. According to the sensory evaluation, the use of 5% BFF increased the odor of meatballs without significantly affecting the other sensory scores. This work demonstrated that BFF may be a healthier alternative as pork fat replacer for preparing meatballs.

Since the majority of valuable components in spent lithium-ion batteries, such as lithium, exists in the electrode materials, common studies focused on the treatment of the cathode materials, which ignored the harm of residual electrolyte. The cavitation and thermal effects produced by ultrasonic can not only be used for the separation of electrode materials, but also have a wide range of applications in the field of sewage pollutant degradation. This work used ultrasonic to treat simulated electrolyte (propylene carbonate (PC)) solution of spent lithium-ion batteries, explored the effect of ultrasonic power, the addition amount of H2O2 solution (30 wt%) and reaction temperature on the degradation of electrolyte, and analysed the ultrasonic degradation reaction from the perspective of reaction kinetics. And the synchronous experiment of cathode material separation and electrolyte degradation was conducted under the optimal conditions. The results showed that the highest degradation efficiency of PC in the electrolyte was 83.08% under the condition of ultrasonic power of 900 W, the addition of H2O2 solution (30 wt%) of 10.2 mL, reaction temperature of 120°C and reaction time of 120 minutes, and the separation efficiency was 100%. This work reduced the environmental and health risks in the cathode material separation process and was conducive to the green development of spent lithium-ion battery recycling technology.

Polymer science entails the structural study at multi-levels from nano- to micro- and mesoscale, which is highly important to transfer or even amplify the molecular information to macroscopic materials. Multiple polymer structural transitions from lower-order to higher-order superstructures are normally involved to achieve selective, efficient and sophisticated functions. Therefore, in-situ visualization of these processes is highly important, not only for fundamental understanding the structural evolution, but also for the optimization of the process flow during the materials processing. Fluorescence imaging based on aggregation-induced emission(AIE) provides an ideal tool that offers a simple, accurate, and easy-readable method to fulfill the above requirements. Owing to the twisted propeller-like structure of AIE luminogens(AIEgens), they show high fluorescence sensitivity to the surrounding microenvironment(e.g., viscosity, rigidity, and polarity) through intramolecular motions. In this short review, we summarize the recent applications of AIEgens to serve as “built-in” sensors to analyze the process of polymerization, microphase separation, glass/vitrification transition, polymer solvation, crystallization, etc. The perspective on the future application of AIE technology in polymer engineering, especially fiber materials, is also discussed.

Environmental monitoring and personal protection are critical for preventing and for protecting human health during all infectious disease outbreaks (including COVID-19). Fluorescent probes combining sensing, imaging and therapy functions, could not only afford direct visualizing existence of biotargets and monitoring their dynamic information, but also provide therapeutic functions for killing various bacteria or viruses. Luminogens with aggregation-induced emission (AIE) could be well suited for above requirements because of their typical photophysical properties and therapeutic functions. Integration of these molecules with fibers or textiles is of great interest for developing flexible devices and wearable systems. In this review, we mainly focus on how fibers and AIEgens to be combined for health protection based on the latest advances in biosensing and bioprotection. We first discuss the construction of fibrous sensors for visualization of biomolecules. Next recent advances in therapeutic fabrics for individual protection are introduced. Finally, the current challenges and future opportunities for "AIE + Fiber" in sensing and therapeutic applications are presented.

The purpose of this study was to investigate the endogenous cathepsin activity in each subcellular fraction and the effect of this activity on myofibrillar protein and texture during refrigeration and partial freezing storage of northern pike (Esox lucius) fillets. The results showed that fillets stored under the refrigerated condition were more susceptible to oxidation than partial freezing. Endogenous cathepsin activity indicated that partial freezing destroys the integrity of lysosomes more effectively than refrigeration and inhibits the increase in cathepsin B and B + L in lysosomes. The activity of cathepsin B and B + L in lysosomes, mitochondria and myofibrils under the partial freezing conditions was always lower than that under refrigeration. Texture analysis showed that refrigeration had a negative impact on hardness and springiness. In conclusion, the cathepsin activity in each subcellular fraction was effectively inhibited and better textural characteristics were obtained with partial freezing than refrigeration. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10068-020-00781-z) contains supplementary material, which is available to authorized users.

Crystal-structured acicular-mullite ceramic with high porosity and interpenetrated networks was fabricated for diesel particulate filter (DPF), followed by electroless deposition of platinum (Pt) catalysis throughout ceramic surfaces from an aqueous Pt (IV) solution. The integrated material was characterized and compared with commercial cordierite particulate matter (PM) filter, exhibiting many excellent properties in surface area, porous ratio, and loading capacity for both soot and catalyst. The resulting surface density of Pt nanoparticles attained as high as 8.0 × 109/cm2 due to the 3-dimensional architecture, while maintaining a pore ratio, 63.72%, relative to 52.60% in its counterpart. Deposited Pt nanoparticles artfully serve as catalysis for combustion of carbon soot, potentially implemented for diesel engine filter, reducing the particulate matter emission for environmental protection. The catalytic performance was evaluated by a regular thermal gravity analysis (TGA) measurement, showing that the significant drop of soot conversion temperature, and soot convert rate could be further improved by co-precipitating CeO2 catalyst additive. This material, thereby, could readily adapt itself into large-scale production.

The wide use of lithium ion batteries (LIBs) has created much waste, which has become a global issue. It is vital to recycle waste LIBs considering their environmental risks and resource characteristics. Anode graphite from spent LIBs still possess a complete layer structure and contain some oxygen-containing groups between layers, which can be reused to prepare high value-added products. Given the intrinsic defect structure of anode graphite, copper foils in LIB anode electrodes, and excellent properties of graphene, graphene oxide–copper composite material was prepared in this work. Anode graphite was firstly purified to remove organic impurities by calcination and remove lithium. Purified graphite was used to prepare graphene oxide–copper composite material after oxidation to graphite oxide, ultrasonic exfoliation to graphene oxide (GO), and Cu2+ adsorption. Compared with natural graphite, preparing graphite oxide using anode graphite consumed 40% less concentrated H2SO4 and 28.6% less KMnO4. Cu2+ was well adsorbed by 1.0 mg L−1 stable GO suspension at pH 5.3 for 120 min. Graphene oxide–copper composite material could be successfully obtained after 6 h absorption, 3 h bonding between GO and Cu2+ with 3/100 of GO/CuSO4 mass ratio. Compared to CuO, graphene oxide–copper composite material had better catalytic photodegradation performance on methylene blue, and the electric field further improved the photodegradation efficiency of the composite material.

With the increasing adoption of EVs (electric vehicles), a large number of waste EV LIBs (electric vehicle lithium-ion batteries) were generated in China. Statistics showed generation of waste EV LIBs in 2016 reached approximately 10,000 tons, and the amount of them would be growing rapidly in the future. In view of the deleterious effects of waste EV LIBs on the environment and the valuable energy storage capacity or materials that can be reused in them, China has started emphasizing the management, reuse, and recycling of them. This paper presented the generation trend of waste EV LIBs and focused on interrelated management development and experience in China. Based on the situation of waste EV LIBs management in China, existing problems were analyzed and summarized. Some recommendations were made for decision-making organs to use as valuable references to improve the management of waste EV LIBs and promote the sustainable development of EVs.

With the rapid development of electronic industry and improvement of living standards, a large number of waste mobile phones were generated. According to statistics, approximately 400 million waste mobile phones are generated each year in the world, and 25% of that are contributed by China. Irregular disposal of waste mobile phones will do great harm to environment and human health, while at the same time recycling of them has the potential for high profits. Given the enormous quantity, great harm and resource properties, developed countries have taken necessary measures to manage waste mobile phones. As the largest developing country, China has also set out to pay close attention to waste mobile phones. This paper reviewed the situation of waste mobile phone management in the developed countries, focused on the development of waste mobile phone management in China, and analyzed existing problems. In light of the successful experience of the developed countries, some suggestions were proposed to promote the waste mobile phone management in China and worked as a valuable reference for other countries.

A new lectin was purified from larvae of the fly, Musca domestica L. (Diptera: Muscidae) (MLL-2, 38 kDa) using affinity chromatography and HPLC. Anti-tumor activity of MLL-2 was demonstrated by its inhibition of proliferation of human breast cancer (MCF-7) cells in a time-and dose-dependent manner. The results of acridine orange staining indicated that MLL-2 caused apoptosis in MCF-7 cells. DNA fragmentation in MCF-7 cells has been detected by TUNEL. Flow cytometric analysis also demonstrated that MLL-2 caused dose-dependent apoptosis of MCF-7 cells through cell arrest at G2/M phase. The MLL-2 induced a sustained increase in concentration of intracellular free calcium. Western blot revealed that MLL-2 induced apoptosis in MCF-7 cells was associated with typical apoptosis proteins in the mitochondrial pathway. In addition, the caspase-3 activity in MCF-7 cells treated with MLL-2 for 48 hours was significantly increased compared to controls (407.4 ± 3.0 vs. 1749.2 ± 6.0, P

A lectin with potent mitogenic activity was isolated from Musca domestica pupae. The lectin was a monomer with a molecular weight of 55 kDa. The purification procedure mainly involved affinity chromatography on galactose-Sepharose-4B. The lectin agglutinated trypsin-treated rabbit blood cells. D-galactose was detected to inhibit the lectin's hemagglutination activity. The lectin was metal independent and temperature dependent and was detected by the periodic acid-Shiff reaction to be a glycoprotein with a carbohydrate content of 2.1%. Observations with an atomic force microscope indicated that the lectin was a globular protein about 75 nm in size, with several carbohydrate chains linked to it. It elicited a mitogenic response from mouse splenocytes in vitro, with the maximal response at a concentration of 20 microg/ml. No lectin has been reported before from Musca domestica pupae, and the lectin we discovered could be of great importance in insect immunity and hypoimmune diseases.

A lectin from Musca domestica larva was purified by affinity chromatography on a glactose-Sepharose 4B column. Musca domestica larva lectin (MLL) inhibited the growth of BEL-7402 cells in a time and concentration-dependent way. The results of Hoechst 33258 staining indicated that MLL induce BEL-7402 cells apoptosis based on the typical apoptotic morphological changes. Subsequently, we found that MLL treatment abrogated glutathione antioxidant system and induced mitochondria to generate reactive oxygen species (ROS) accumulation, resulting in reduction of mitochondrial transmembrane potential. The induction of cell apoptosis was caused by the upregulation of Bax, the downregulation of Bcl-2, the cytochrome c release and the activation of the caspases pathways.

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A subspace-projection method is developed to construct orthogonal block variable, which is originally from some kinds of series of topological indices or quantum chemical parameters. With the help of canonical correlation analysis, the orthogonal block variables were used to establish the structure-retention index correlation model. The regression of only few new orthogonal variables obtained by canonical correlation analysis against retention index shows significant improvement both in fitting and prediction ability of the correlation model. Moreover, the quantitative intercorrelation between the different block variables of topological indices can also be evaluated with the help of the subspace-projection technique proposed in this work.