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Advanced sensation and actuation abilities of various living organisms in nature have inspired researchers to design bioinspired self‐sensing soft actuators. However, the majority of conventional soft actuators primarily possess actuation capabilities while lacking a real‐time sensing signal feedback. Here, a promising strategy is reported to develop highly stretchable and conductive hydrogels for bioinspired self‐sensing soft actuators, which integrate actuation and strain‐sensing functions into a single materials system. The conductive hydrogels are designed and fabricated by in situ copolymerization of amino‐functionalized MXene‐encapsulated liquid metal nanodroplets (LM@A‐MXene) and poly(N‐isopropylacrylamide) hydrogels with controllable activated nanogels as nano‐cross‐linkers. The resulting hydrogel presents a compacted conducting network and highly porous microstructure, giving rise to robust integration of high conductivity, excellent strain sensitivity, broad stretchability, high stability, and fast response speed. Interestingly, the gradient network structure, formed by self‐precipitation of LM@A‐MXene, endows the hydrogel with shape‐programmable actuation, light‐driven remote control, and self‐sensing function. As a proof‐of‐concept application, the soft gripper based on the self‐sensing hydrogel actuators is developed, which can not only grasp, lift, and release objects, but also perceive every movement state by monitoring resistance changes. The proposed self‐sensing soft actuator can offer new insights for developing smart soft robotics and other artificial intelligent devices. [ABSTRACT FROM AUTHOR]

Organic cycles play an important role in chemistry, pharmacology and material science for their unique properties. Construction of organic cycles from thioalkynes attracted increasing attention due to the facile access of thioalkynes. 2H‐Azirines were synthesized successfully from thioalkynyl oxime ethers. Cyclobutanes were formed through chiral titanium catalyzed cycloaddition of thioalkynes. Cyclopentenes were afforded by annulation of thioalkynes. Thioalkynes could be also applied to synthesize thiophenes, oxazoles, benzo[b]thiophenes, 2H‐chromenes, 2‐phenylbenzothiazoles, diazacyclobutene, etc. In this review, construction of organic cycles from thioalkynes were highlighted. Firstly, the property and application of organic cyclic compounds were simply introduced. After presenting the general methods to access organic cycles, applications of thioalkynes as synthons to prepare organic cycles were classified and presented in detail. Based on different kinds of organic cycles obtained from thioalkynes, organic reactions for synthesis of three‐, four‐, five‐, six‐membered as well as fused cycles would be summarized and the plausible reaction mechanisms could be presented if available. [ABSTRACT FROM AUTHOR]

Sulfur‐containing alkynes, are important starting materials and intermediates in organic reactions. Some of sulfur‐containing alkynes display interesting bioactivities and are potentially applied as drugs. Various synthetic methodologies towards sulfur‐containing alkynes have been developed, including C(sp)−S coupling, thiolation, S‐alkynylation, trifluoromethylthiolation, etc. In this review, the approaches towards alkynyl sulfides in recent 3 years, as well as to form alkynyl trifluoromethyl sulfides and alkynylthiocyanates were highlighted. Firstly, the property and application of alkynes were introduced. After presenting the superiority of sulfur‐containing alkynes, their synthetic methods were classified and presented in details. According to different kinds of sulfur‐containing alkynes, synthetic methodologies for alkynyl sulfides, alkynyl trifluoromethyl sulfides and alkynylthiocyanates were summarized and the proposed reaction mechanisms were demonstrated if available. [ABSTRACT FROM AUTHOR]

Sophisticated sensing and actuation capabilities of many living organisms in nature have inspired scientists to develop biomimetic somatosensory soft robots. Herein, the design and fabrication of homogeneous and highly conductive hydrogels for bioinspired somatosensory soft actuators are reported. The conductive hydrogels are synthesized by in situ copolymerization of conductive surface‐functionalized MXene/Poly(3,4‐ethylenedioxythiophene)/poly(styrenesulfonate) ink with thermoresponsive poly(N‐isopropylacrylamide) hydrogels. The resulting hydrogels are found to exhibit high conductivity (11.76 S m−1), strain sensitivity (GF of 9.93), broad working strain range (≈560% strain), and high stability after over 300 loading–unloading cycles at 100% strain. Importantly, shape‐programmable somatosensory hydrogel actuators with rapid response, light‐driven remote control, and self‐sensing capability are developed by chemically integrating the conductive hydrogels with a structurally colored polymer. As the proof‐of‐concept illustration, structurally colored hydrogel actuators are applied for devising light‐driven programmable shape‐morphing of an artificial octopus, an artificial fish, and a soft gripper that can simultaneously monitor their own motions via real‐time resistance variation. This work is expected to offer new insights into the design of advanced somatosensory materials with self‐sensing and actuation capabilities, and pave an avenue for the development of soft‐matter‐based self‐regulatory intelligence via built‐in feedback control that is of paramount significance for intelligent soft robotics and automated machines. [ABSTRACT FROM AUTHOR]

With the growth of high performance electronics, more consideration should be given to the safety issues associated with thermal runaway. Previous strategies have often been limited by shutdown efficiency and shutdown temperature. Here, we present a MXene supercapacitor loaded with a smart thermally responsive electrolyte to cope with thermal runaway at high temperatures. At room temperature, the ions in the electrolyte containing the poly (N‐isopropylacrylamide‐co‐glycidyl methacrylate) (PNGM) can migrate freely and the devices can operate normally. The smart electrolyte system forms a hydrophobic network that effectively inhibits ion migration to achieve thermal shutdown at high temperatures. The electrolyte system exhibits different electrochemical properties during heating up, reaching nearly 90 % capacity suppression at 85 °C. The proposed smart electrolyte system provides a promising solution to the thermal safety suitable for current electronic devices by achieving a proactive protection strategy. [ABSTRACT FROM AUTHOR]

Flexible artificial intelligence and rechargeable electronic devices have been the research hotpot due to the status quo of the energy crisis. However, the existing energy storage devices suffering from undesirable electrochemical performance, poor flexibility, and toxicity, have unsatisfactory practical application prospect. Owing to its unique stability, normal electrodes in energy storage equipment are built out of carbon‐based materials. Recently, zinc hybrid supercapacitors have attracted a lot of attention. Herein, a high‐performance zinc‐ion hybrid micro‐supercapacitor is successfully constructed using hierarchical honeymoon‐like porous carbon frameworks as cathode by direct ink printing method. Due to the bivalent feature of zinc and electric double layered capacitive characteristic of the porous carbon, the optimized device possesses excellent electrochemical performance of excellent specific capacity of 189.06 mA h g−1 at a current density of 1 mA cm−2, high energy density of76.38 Wh kg−1, power density of 499.94 W kg−1 and superior capacity retention of 95.71 % at 10 mA cm−2 after 1000 cycles. Through direct ink printing, the as‐assembled zinc hybrid micro‐supercapacitors based on flexible substrate exhibit outstanding flexibility with controllable active material mass loading. [ABSTRACT FROM AUTHOR]

Purpose: Coronavirus disease 2019 (COVID‐19) has caused a serious global health crisis. It has been proven that the deep learning method has great potential to assist doctors in diagnosing COVID‐19 by automatically segmenting the lesions in computed tomography (CT) slices. However, there are still several challenges restricting the application of these methods, including high variation in lesion characteristics and low contrast between lesion areas and healthy tissues. Moreover, the lack of high‐quality labeled samples and large number of patients lead to the urgency to develop a high accuracy model, which performs well not only under supervision but also with semi‐supervised methods. Methods: We propose a content‐aware lung infection segmentation deep residual network (content‐aware residual UNet (CARes‐UNet)) to segment the lesion areas of COVID‐19 from the chest CT slices. In our CARes‐UNet, the residual connection was used in the convolutional block, which alleviated the degradation problem during the training. Then, the content‐aware upsampling modules were introduced to improve the performance of the model while reducing the computation cost. Moreover, to achieve faster convergence, an advanced optimizer named Ranger was utilized to update the model's parameters during training. Finally, we employed a semi‐supervised segmentation framework to deal with the problem of lacking pixel‐level labeled data. Results: We evaluated our approach using three public datasets with multiple metrics and compared its performance to several models. Our method outperforms other models in multiple indicators, for instance in terms of Dice coefficient on COVID‐SemiSeg Dataset, CARes‐UNet got the score 0.731, and semi‐CARes‐UNet further boosted it to 0.776. More ablation studies were done and validated the effectiveness of each key component of our proposed model. Conclusions: Compared with the existing neural network methods applied to the COVID‐19 lesion segmentation tasks, our CARes‐UNet can gain more accurate segmentation results, and semi‐CARes‐UNet can further improve it using semi‐supervised learning methods while presenting a possible way to solve the problem of lack of high‐quality annotated samples. Our CARes‐UNet and semi‐CARes‐UNet can be used in artificial intelligence‐empowered computer‐aided diagnosis system to improve diagnostic accuracy in this ongoing COVID‐19 pandemic. [ABSTRACT FROM AUTHOR]

Herein, we report near‐infrared (NIR) light‐driven shape‐morphing of programmable MXene‐containing anisotropic hydrogel actuators that are fabricated through in situ free‐radical copolymerization of a judiciously designed MXene nanomonomer with thermosensitive hydrogel network. A low electric field (few V mm−1) was found to enable a spatial distribution of MXene nanosheets and hence introduce anisotropy into the hydrogel network. Programmable anisotropic hydrogel actuators were developed by controlling ITO electrode pattern, direct‐current (DC) electric field direction and mask‐assisted photopolymerization. As a proof‐of‐concept, we demonstrate NIR light‐driven shape morphing of the MXene‐containing anisotropic hydrogel into various shapes and devise a four‐arm soft gripper that can perform distinct photomechanical functions such as grasping, lifting/lowering down and releasing an object upon sequential NIR light exposure. [ABSTRACT FROM AUTHOR]

Wearable electronic devices need ceaseless improvement in performance and flexibility. However, few studies were focused on high mass loading electrodes. Herein, a 3D printing method was demonstrated to fabricate the high‐performance supercapacitor on flexible carbon cloth using polypyrrole (PPy) nanotubes as electrode materials. The mass loading could achieve 336.56 mg cm−2 through direct ink printing (DIW) technology. In addition, the 3D printed supercapacitor exhibits excellent mechanical stability, the capacitance of the printed device remains 93% at the bending angle of 120°. Its promising performance and outstanding electrochemical stability will provide an ideal method to fabricate wearable storage devices. [ABSTRACT FROM AUTHOR]

A metal‐, base‐ and reductant‐free approach for the efficient synthesis of various N‐acylated 2‐aminoquinolines was reported. In this work, readily available nitriles are used as the amide source, and methyl carbazate as both the radical activating reagent and oxygen source. This is the first report on the ester‐radical‐activated highly regioselective addition of nitriles to quinolone N‐oxides. This procedure is expected to complement the current methods for functionalization of N‐oxides via an electrophilic activation mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Bis(pentamethylcyclopentadienyl) zirconium perfluorooctanesulfonate is an air‐stable and water‐tolerant Lewis acid. This complex exhibited good thermal stability and high solubility in polar organic solvents. The compound showed relatively strong acidity, with an acid strength of 0.8

Abstract: The use of heterogeneous bimetallic Pd‐based nanocatalyst for directing the inactivated sp3 C−H coupling has been scarcely explored. This work reported the formation of symmetrical C−C bonds from the inactivated sp3 C−H bonds catalyzed by employing reduced graphene oxide supported PtPd@Pt porous nanospheres. The reaction of sp3 C−H activation proceeded under mild conditions without any solvent, ligand or directing group. It is a higher atom‐, step‐ and cost‐effectiveness strategy for developing heterogeneous catalysts in the synthesis of bibenzyls with various functional groups (e. g. aryl, alkyl, methoxyl, halogen, ester, and pyridyl). [ABSTRACT FROM AUTHOR]

Triphenyl bismuth bisperfluorooctanesulfonate is an air- and water-stable Lewis acid. It exhibits high catalytic efficiency for the synthesis of nitrogen heterocycles such as diindolylmethane derivatives, dihydropyrimidinones, dihydropyridines and 1,2-disubstitued benzimidazoles under mild condition. Furthermore, it can be reused without loss of activity in a test of five cycles.This catalytic system affords a simple and efficient way for the synthesis of N-containing compounds. [ABSTRACT FROM AUTHOR]

This study investigates the removal of Cr(VI) by nanoscale zero-valent iron (nZVI)-multiwalled carbon nanotubes (MWCNTs) composites from aqueous solutions. Various influential environmental factors including temperature, pH, co-existing ions, and natural organic matters (NOM) on Cr(VI) removal were evaluated. Results revealed that temperature variations significantly influenced Cr(VI) removal and the efficiency decreased to 22% with increasing in temperature from 10 to 40°C. Cr(VI) removal efficiency decreased with increasing pH and the final pH increased to 9.1, 10.1, and 10.2 from 5, 7, and 9, respectively, after 2 h of the reaction. Interestingly, most of the co-existing ions except copper presented comparatively lower final removal rates. However, co-existing ions including Pd2+, Ca2+, Zn2+, and Mg2+ facilitated higher Cr(VI) removal. Copper was observed to greatly promote the reaction and 99.5% removal efficiency was achieved within 30 min after adding 20 mg L−1 of Cu2+. In contrast, Cr(VI) removal efficiency drastically dropped to 58.9% from 97.9% in the presence of As(V). At higher concentrations of humic and tannic acid; the two representatives of NOM were observed to exhibit a negative impact on Cr(VI) removal. The changes appeared on nZVI-MWCNTs before and after the reaction with Cr(VI) were investigated by transmission electron microscopy. The reusability of nZVI-MWCNTs showed a recovery rate of 53.4% in the third round and demonstrated a better utility of nZVI-MWCNTs composites in wastewater treatment applications. [ABSTRACT FROM AUTHOR]

This study is related to the removal of organics and other pollutants from drinking water using an integrated treatment system consisting of coagulation-sedimentation, ozonation and granular activated carbon (GAC)-enhanced sand filtration. Standard methods and instruments were employed to measure turbidity, chemical oxygen demand determined by using the permanganate method as permanganate index (CODMn), UV254, total organic carbon (TOC), ammonia and nitrite of raw and treated water under controlled laboratorial conditions. The experimental results demonstrated that the total removal rates of turbidity, CODMn, UV254 and TOC were in the range of 98-99.9, 21-71, 33-73 and 20-47%, respectively, in different units of the integrated treatment system. GAC-enhanced sand filtration significantly removed ammonia and nitrite, and the average removal efficiency was attained to 88 and 98%, respectively. In addition, most of the organic matter concentrations were observed to be reduced in GAC-enhanced sand filtration and only small molecular weight compounds were detected in the effluent. All these pollutant reductions were noticed in the upper 350 mm of the activated carbon column in GAC-enhanced sand filtration. The findings from this study suggest that the integrated treatment process can efficiently remove organics and other toxic pollutants from drinking water and can be a better alternative to conventional treatment. [ABSTRACT FROM AUTHOR]

Elevated arsenic concentrations have been detected in drinking water sources worldwide and it threatens to over 200 million people in both developing and developed countries. Adsorption is a conventional process for arsenic removal from contaminated water. Several classes of adsorbing materials have been tested so far. However, far less attention was paid towards granular-based adsorption and granulation processes. The present work is the first attempt to consider both the granular adsorbent and the granulation process. A particular emphasis was given to cost-efficient adsorbent for small scale arsenic removal. Some of the features of granular adsorbents are summarized in tables and graphs; address necessary outlines for readers to easily overview the adsorbents' characteristics and design sustainable adsorption system. Earlier, cost of arsenic removals from granular adsorbents were not widely affirmed, but in this review few of them are incorporated for comparisons in future studies. Thus, one gram of arsenic removal from water using novel and iron oxide-coated sand adsorbents is approximately ranged US$2.3-5.1 and US$3.3-4.2, respectively. Moreover, methods employed for regeneration of exhausted granular adsorbents are discussed. Field scale arsenic remediation measures and the performance evaluations are additionally reported to identify the feasibility of these approaches for scaling up, awareness raising and promotion. [ABSTRACT FROM AUTHOR]

In the present study, coupled reduction-sorption of Cr(VI) using three iron containing minerals (magnetite, hematite, and pyrrhotite) in aqueous solutions was investigated as a function of solution pH, contact time, and particle size. Detailed characterizations were performed using Brunauer-Emmett-Teller (BET), environmental scanning electron microscopy, and X-ray diffraction (XRD) techniques. Results demonstrated that over 99% of Cr(VI) removal was achieved just after 1 min of the reaction using pyrrhotite with particle size (100-200 mesh). In comparison, removal efficiency of hematite and magnetite against Cr(VI) was below 40% after 2 h of the reaction. Acidic aqueous medium proved effective for Cr(VI) removal and nearly 100% Cr(VI) removal was achieved at pH 3 using pyrrhotite (30-40 mesh), while the surface efficacy of hematite and magnetite has also improved in acidic solution. In terms of removal efficiency, the three minerals followed the order: pyrrhotite > magnetite > hematite. However, no significant difference in the BET specific surface area was recorded among these minerals, but the mineralogical compositions played an important role for removing Cr(VI) in aqueous solutions. Analysis of XRD pattern revealed that iron contents produce Fe3FeSiO4(OH)5 and FeCr2O4 after the reaction with soluble Cr(VI) and precipitated. This study suggested that high ferrous ions-based minerals can effectively remove Cr(VI) from contaminated water environments. [ABSTRACT FROM AUTHOR]

The inhibitory effect of barley straw ( Hordeum vulgare) on cyanobacteria has been observed in many field and laboratory studies for over 30 years, although the compounds responsible for this anti-cyanobacterial effect have remained unknown. In this study, a pair of chiral flavonolignans were isolated from barley straw extract using a bioassay-guided isolation procedure against Microcystis sp. The structures of the allelopathic compounds were elucidated by NMR (nuclear magnetic resonance) and HPLC-MS (high performance liquid chromatography-mass spectrometry), and turned out to be salcolin A and B. The enantiomers differ in their anti-cyanobacterial abilities. Both enantiomers exhibited inhibitory effects on Microcystis sp., and the EC50 (concentration for 50% of maximal effect) of salcolin A and B were 6.02 × 10−5 and 9.60 × 10−5 mol l−1, respectively. Furthermore, the modes of actions of the enantiomers were investigated and compared at a single cell level by flow cytometry. Salcolin A was found to induce an increase on cyanobacterial intracellular ROS (reactive oxygen species) levels and to inhibit esterase activity, whereas salcolin B caused leakages of cyanobacterial cytoplasms. Thus, salcolin A was more 'algistatic', and salcolin B was more 'algicidal'. This study suggests that salcolin is the key allelochemical in barley straw's inhibitory effect on cyanobacteria and could be used as an agent in the future control of cyanobacterial harmful algae blooms. [ABSTRACT FROM AUTHOR]

The two air-stable μ2-hydroxy-bridged binuclear hafnocene perfluorobutanesulfonate and perfluorobenzenesulfonate complexes were successfully synthesized. The high catalytic activity and recyclability of these complexes were exemplified for various carbon-carbon bond formation reactions. Compared with our previously reported hafnocene perfluorooctanesulfonate, these complexes show stronger Lewis acidity and better catalytic activity, and should find broad applications in organic synthesis. [ABSTRACT FROM AUTHOR]

Sulfate in groundwater has been previously shown to change the reactivity of Fe0 in permeable reactive barriers for reducing chlorinated organics. To better understand the effect and mechanism of SO, the degradation of 1,1,1-trichloroethane (TCA) by Fe0 in unbuffered aqueous solutions with and without SO was investigated. In a Fe0-TCA-H2O system with initial pH of 2.0 to 10.0, the maximum removal rate of TCA was achieved at the initial pH 6.0 with pseudo-first-order constant Kobs 9.0 × 10−3/min. But in a Fe0-TCA-Na2SO4-H2O system, the removal rate of TCA decreased remarkably with a reduction in Kobs to 1.0 × 10−3/min, and the pH varied from 6.0 to 9.6, indicating an inhibition of TCA dehydrochlorination by SO. Sulfate remarkably inhibited TCA degradation via changing the route of Fe0 dissolution. It accelerated the dissolution of Fe0 and transformed the intermediate form Fe(OH)ads to Fe2(SO4)ads, which weakened the affinity between Fe and TCA, and thus depressed the degradation of TCA by Fe0. [ABSTRACT FROM AUTHOR]

In this article, the effects of low temperature Ar glow discharge plasma modification on the surface of polypropylene (PP) and polystyrene (PS) plates were characterized by X-ray photoelectron spectroscopy, and the temporal change of the complex viscosity (η*) of PP/PS plates with a sandwich structure were measured by a rotational rheometer. The results showed that the formation of reactive groups on the surface of PP and PS plates was due to the reaction of O2 with some free radicals when exposed to air. In the rheology study, because of the increase of interfacial adhesion strength due to the coupling reaction between the reactive groups at the interface, η* increased with welding time. There were two distinct stages for the changes of η* with welding time. In Stage I, η* increased rapidly and indicated a reaction-controlled kinetics, the apparent reaction kinetics was a first-order reaction; in Stage II, η* increased slowly and indicated a diffusion-controlled reaction. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

In this study, we show that the plasma-initiated polymerization (PIP) can be carried out at ambient pressure using the dielectric barrier discharge (DBD) technology. The structure of styrene-maleic anhydride copolymer (SMA) is analyzed by 1H and 13C-NMR. The effects of initiation time, gas flow rate, post-polymerization time, and temperature on yield are also discussed. The results show that SMA exhibits a dominant alternating structure. The yield of SMA increases with the increase of initiation time and polymerization temperature, remains unchanged with the increase of flow rate, and decreases rapidly with the increase of St-MAH molar ratio. The PIP in this experiment is shown to follow the free-radical polymerization mechanism and the process of the polymerization is also discussed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

In the synthesis of binuclear organobismuth complexes ( 1- 6) through treatment of organobismuth chlorides with NaOH or Na2S⋅9H2O, the two 5,6,7,12-tetrahydrodibenz [ c,f][1,5]azabismocine frameworks are cross-linked by either a sulfur or an oxygen atom. The complexes ( 1- 6) show high catalytic efficiency in the synthesis of cyclic carbonates from 2-(chloromethyl)oxirane and CO2. Compared with their precursor chlorides ( 7- 9), methoxide 10 and methanethioate 11 which are mononuclear organobismuth complexes, the binuclear organobismuth complexes show higher cooperative catalytic effect. However, the complexes with an oxygen bridge ( 1- 3) are not stable in air and lose their catalytic efficiency because of hydrolysis or CO2 adsorption (forming organobismuth carbonates in the latter case). Nonetheless, the binuclear organobismuth complexes ( 4- 6) with a sulfur bridge are highly stable in air and can be applied in the synthesis of cyclic carbonates (with the co-presence of Bu4NI) across various kinds of epoxides, thus exhibiting satisfactory efficiency and selectivity. [ABSTRACT FROM AUTHOR]

Magnesium alloys may potentially be applied as biodegradable metallic materials in cardiovascular stent. However, the high corrosion rate hinders its clinical application. In this study, a new approach was adopted to control the corrosion rate by fabricating a biocompatible micro-arc oxidation/poly- L-lactic acid (MAO/PLLA) composite coating on the magnesium alloy WE42 substrate and the biocompatibility of the modified samples was investigated. The scanning electronic microscope (SEM) images were used to demonstrate the morphology of the samples before and after being submerged in hanks solution for 4 weeks. The degradation was evaluated through the magnesium ions release rate and electrochemical impedance spectroscopy (EIS) test. The biocompatibility of the samples was demonstrated by coagulation time and hemolysis behavior. The result shows that the poly- L-lactic acid (PLLA) effectively improved the corrosion resistance by sealing the microcracks and microholes on the surface of the MAO coating. The modified samples had good compatibility. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011. [ABSTRACT FROM AUTHOR]

An air‐stable complex of zirconium (IV)‐salophen perfluorooctanesulfonate (1) was successfully synthesized by reacting Zr (salphen)Cl2 and C8F17SO3Ag. Complex 1 was characterized and studied by different techniques (NMR, IR, HRMS, TG‐DSC, conductivity and acidity measurements), and was found to be air‐stable, water tolerant, thermally stable and strongly Lewis‐acidic. Complex 1 exhibited high catalytic efficiency for the synthesis of 3,4‐dihydropyrimidin‐2‐(1H)‐ones/thiones via the Biginelli reaction of aldehydes, 1,3‐dicarbonyl compounds and urea/thiourea under solvent‐free conditions. Furthermore, complex 1 could be reused 5 times with minimal changes in catalytic efficiency. Compared with previously reported methods, the important features of this protocol are the solvent‐free conditions, the short reaction times, the wide substrate compatibility, the high efficiency and the good reusability. [ABSTRACT FROM AUTHOR]

A protein is generally classified into one of the following four structural classes: all α, all β, α+β and α/β. In this paper, based on the weighting to the 20 constituent amino acids, a new method is proposed for predicting the structural class of a protein according to its amino acid composition. The 20 weighting parameters, which reflect the different properties of the 20 constituent amino acids, have been obtained from a training set of proteins through the linear-programming approach. The rate of correct prediction for a training set of proteins by means of the new method was 100%, whereas the highest rate of previous methods was 82.8 %. Furthermore, the results showed that the more numerous training proteins, the more effective the new method. [ABSTRACT FROM AUTHOR]

A heterogeneous Pd‐Cu NWs‐catalyzed expeditious and solvent‐free synthesis of propargylamines via A3‐coupling of aldehydes, alkynes, and amines has been proposed. A wide range of aldehydes, alkynes and amine substrates undergo A3‐coupling to produce propargylamines in good to excellent yields with good functional tolerance, such as that towards alkoxy, hydroxy, C‐X (X = F, Cl, Br) as well as amide and C=C bonds. Furthermore, the catalyst could be recovered easily and reused for at least 5 cycles without showing significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]