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Fire safety issues hinder the large‐scale application of lithium‐ion batteries (LiBs). Here, a new type of fire‐response separators is prepared by loading the microcapsule fire extinguishing agent on the surface of the separator. The shell of the microcapsule will break automatically at a certain temperature and release the fire extinguishing agent when thermal runaway of LiBs occurs, which can quickly absorb heat through endothermic reaction and ensure LiBs will not burn or explode. The porosity of fire‐response separator is 53.6%, the electrolyte uptake is 132% and the ionic conductivity is 1.00 mS cm‐1. The initial specific capacity is 2643 mAh g‐1 at 4°C and the capacity retention rate is 93% after 200 cycles for NCM523 battery based fire‐response separator. The temperature of LiBs based on the fire‐response separator can automatically drop to room temperature in 20 seconds, which ensures the safety of other adjacent LiBs. This work proposes a new active protection concept to solve the safety problem of LiBs. [ABSTRACT FROM AUTHOR]

Material characterization has been proved to be the most intuitive approach to understand the chemical composition, structure, and microstructure of materials, which is the basis of material design. One of the most important steps in material design is to extract the characteristics from an image, and find their associations with the material structure and properties. Therefore, in recent years, with the rapid development of machine vision algorithms, characterization images have attracted attention in the field of material characterization. Researchers use computer vision algorithms, such as image denoising and enhancement, to preprocess the representation image, image segmentation and classification to detect and separate each microstructure from the characterization image, and quantitatively analyze the properties of materials. Herein, the application of computer vision algorithms in material image representation is summarized and discussed. The latest and valuable views for experts and scholars in both computer vision and material grounds are presented. Thus, this review provides guidance for material exploration and promotes the developments of artificial intelligence in the field of materials. [ABSTRACT FROM AUTHOR]

Polymers have been widely used in energy storage, construction, medicine, aerospace, and so on. However, the complexity of chemical composition and morphology of polymers has brought challenges to their development. Thanks to the integration of machine learning algorithms and large data resources, the data‐driven methods have opened up a new road for the development of polymer science and engineering. The emerging polymer informatics attempts to accelerate the performance prediction and process optimization of new polymers by using machine learning models based on reliable data. With the gradual supplement of currently available databases, the emergence of new databases and the continuous improvement of machine learning algorithms, the research paradigm of polymer informatics will be more efficient and widely used. Based on these points, this paper reviews the development trends of machine learning assisted polymer informatics and provides a simple introduction for researchers in materials, artificial intelligence, and other fields. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) has received widespread attention over the last few decades due to its potential to increase automation and accelerate productivity. In recent years, a large number of training data, improved computing power, and advanced deep learning algorithms are conducive to the wide application of AI, including material research. The traditional trial‐and‐error method is inefficient and time‐consuming to study materials. Therefore, AI, especially machine learning, can accelerate the process by learning rules from datasets and building models to predict. This is completely different from computational chemistry where a computer is only a calculator, using hard‐coded formulas provided by human experts. Herein, the application of AI in material innovation is reviewed, including material design, performance prediction, and synthesis. The realization details of AI techniques and advantages over conventional methods are emphasized in these applications. Finally, the future development direction of AI is expounded from both algorithm and infrastructure aspects. [ABSTRACT FROM AUTHOR]

It is a challenging task to prepare well‐dispersed and highly luminescent quantum dots (QDs) powder and a new strategy is reported in this article. Sodium carboxymethyl starch (CMS‐Na) was employed in this work to prepare the QDs–starch composite. Ultraviolet (UV) light shows that the blank starches had no fluorescence, while the QDs‐starches were highly luminescent. Scanning electron microscopy (SEM) observation shows that the QDs–starch composite has the typical particle morphology with the diameter around 200 nm. Energy dispersive X‐ray spectroscopy (EDX) results show that there are intensive tellurium (Te) and cadmium (Cd) element signals. Combined fluorescent lifetime and steady‐state spectrometer show that the QDs–starch quantum yields (QYs) increase when the QDs loading increases from 1 × 10−6 mol/g to 2 × 10−6 mol/g, but when the loadings further increase, the QYs decrease slightly. For the red colour (λem = 660 nm) QDs, the QYs can reach to as high as 28.2%, and for the other colour QDs they can also have the QYs above 22%. Time‐resolved photobleaching experiments show that the fluorescent QDs–starch composite has a half‐decay time of 40.23 s. These results indicate that the CMS‐Na is a promising QDs dispersant to obtain high QY QD composites. [ABSTRACT FROM AUTHOR]

Abstract: A gold nanoparticle/multi‐walled carbon nanotube (Au/MWNTs) hybrid was prepared following the scalable one‐pot reduction of chloroauric acid with tetrakis(hydroxymethyl)chloride in the presence of MWNTs. TEM, XRD, FTIR, XPS, and thermogravimetric analyses indicate that gold nanoparticles (Au NPs, d≈2.9 nm) protected with the tris(hydroxymethyl)oxide (THPO) ligand were deposited on the MWNTs, where no Oswald ripening was observed for the Au NPs after 3000 voltammetric cycling. The Au/MWNTs hybrid with THPO ligand exhibits an impressive catalytic activity toward the oxygen reduction reaction (ORR), following a direct four‐electron mechanism in alkaline solution, and it also manifests excellent long‐term cycling durability and tolerance to the possible crossover methanol. This demonstrates prospective for the hybrid to serve as a stable ORR catalyst for direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Abstract: Lithium sulfur is considered as one of the most potential candidate cathode material using in high‐energy lithium ion batteries. In this work, the N‐doped porous carbon spheres with an appropriate N doping (4.33 wt%) were synthesized by Pyrrole through the sulfuric acid triggered polymerization and carbonized directly. The diameter of obtained N‐doped porous carbon spheres was in the range of 100–500 nm, with the pore size of 2–20 nm. Nitrogen‐doped carbon/Sulfur cathode with 61.8 wt% sulfur content exhibits excellent performance in high‐energy lithium sulfur battery. The specific capacity reached 1660 mAh g −1 at 0.05 C and about 500 mAh g−1 at 2 C. [ABSTRACT FROM AUTHOR]

A quantum dot (QD) dispersant material was prepared using graphite oxide (GO). Luminescent films were prepared using polyvinyl alcohol as the polymer matrix. First, water-soluble CdTe QDs were prepared by wet chemistry and GO was synthesized using a modified Hummers method. X-Ray diffraction tests showed that the GO reflection peak [001] was 11.9°, which indicates that the d-spacing is 0.7431 nm; atomic force microscopy showed a GO thickness of 200 nm. Fourier transform infrared spectra showed vibrations at 1624 cm−1 for the carbonyl groups, and 3260 cm−1 for the GO samples; the -C-O vibration was at 1320 cm−1 and -COOH, −OH vibrations were at 950 cm−1. Fluorescent tests showed that pH had an impact on the QD colloidal stability. GO was neutralized before use as the host media for the GO/QDs nanocomposite. The results proved that the resultant nanocomposite is promising for use in brightness enhancement films in flexible displays. [ABSTRACT FROM AUTHOR]

Urethane acrylate (UA) was used to prepare carbon quantum dots (C-dots) luminescent membranes and the resultants were examined with FT-IR, mechanical strength, scanning electron microscope (SEM) and quantum yields (QYs). FT-IR results showed the polyurethane acrylate (PUA) prepolymer -C = C-vibration at 1101 cm−1 disappeared but there was strong vibration at1687cm−1which was contributed from the-C = O groups in cross-linking PUA. Mechanical strength results showed that the different quantity of C-dots loadings and UV-curing time affect the strength. SEM observations on the cross-sections of the membranes are uniform and have no structural defects, which prove that the C-dots are compatible with the water-soluble PUA resin. The C-dot loading was increased from 0 to 1 g, the maximum tensile stress was nearly 2.67 MPa, but the tensile strain was decreased from 23.4% to 15.1% and 7.2% respectively. QYs results showed that the C-dots in the membrane were stable after 120 h continuous irradiation. Therefore, the C-dots photoluminescent film is the promising material for the flexible devices in the future applications. [ABSTRACT FROM AUTHOR]

This paper studied the effects of cations and polymer matrix on the fluorescent properties of quantum dots (QDs). The results indicated that temperature has a greater impact on fluorescence intensity than clay cations (mainly K+ and Na+). Combined fluorescence lifetime and steady-state spectrometer tests showed that QD lifetimes all decreased when the cation concentration was increased, but the quantum yields were steady at various cation concentrations of 0, 0.05, 0.5 and 1 M. Poly(ethylene oxide) (PEO), poly(vinyl alcohol) (PVA) and diepoxy resin were used to study the effects of polymers on QD lifetime and quantum yield. The results showed that the lifetime for QDs 550 nm in PEO and PVA was 17.33 and 17.12 ns, respectively; for the epoxy resin, the lifetime was 0.74 ns, a sharp decrease from 24.47 ns. The quantum yield for QDs 550 nm changed from 34.22% to 7.45% and 7.81% in PEO and PVA, respectively; for the epoxy resin the quantum yield was 2.25%. QDs 580 nm and 620 nm showed the same results as QDs 550 nm. This study provides useful information on the design, synthesis and application of QDs-polymer luminescent materials. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Transferrin and mouse anti‐human CD71 monoclonal antibody were respectively conjugated covalently to the core/shell CdSe/ZnS quantum dots with 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide hydrochloride and N‐hydrocylsulfo‐succinimide (Sulfo‐NHS). The conjugation worked well and the bioactivities of these macromolecules still remained, which was verified by column filtration, sodium dodecyl sulfate polyacrylamide gel electrophoresis, absorption spectra, fluorescence spectra, and circular dichroism spectrometry. Thus, these two kinds of quantum dot conjugates were used to recognize the tumor cells involved. In case of pseudo positivity, FITC‐labeling secondary antibody IgG was used, and the results showed that as‐prepared fluorescent quantum dot bioprobes were highly specific to tumor cells. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007 [ABSTRACT FROM AUTHOR]

Oxalic acid (OA), a non-host-specific toxin secreted by Sclerotinia sclerotiorum during pathogenesis, has been demonstrated to be a major phytotoxic and pathogenic factor. Oxalate oxidase (OXO) is an enzyme associated with the detoxification of OA, and hence the introduction of an OXO gene into oilseed rape ( Brassica napus L.) to break down OA may be an alternative way of increasing the resistance of the plant to Sclerotinia sclerotiorum. In order to investigate the activation of OXO in transgenic oilseed rape, a convenient and accessible method was used to monitor changes in pH in response to stress induced by OA. The pH sensor, a platinum microcylinder electrode modified using polyaniline film, exhibited a linear response within the pH range from 3 to 7, with a Nernst response slope of 70 mV/pH at room temperature. The linear correlation coefficient was 0.9979. Changes induced by OA in the pH values of leaf tissue of different oilseed rape species from Brassica napus L. were monitored in real time in vivo using this electrode. The results clearly showed that the transgenic oilseed rape was more resistant to OA than non-transgenic oilseed rape. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]