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Advances in targeted covalent inhibitors (TCIs) have been made by using lysine‐reactive chemistries. Few aminophiles possessing balanced reactivity/stability for the development of cell‐active TCIs are however available. We report herein lysine‐reactive activity‐based probes (ABPs; 2–14) based on the chemistry of aryl fluorosulfates (ArOSO2F) capable of global reactivity profiling of the catalytic lysine in human kinome from mammalian cells. We concurrently developed reversible covalent ABPs (15/16) by installing salicylaldehydes (SA) onto a promiscuous kinase‐binding scaffold. The stability and amine reactivity of these probes exhibited a broad range of tunability. X‐ray crystallography and mass spectrometry (MS) confirmed the successful covalent engagement between ArOSO2F on 9 and the catalytic lysine of SRC kinase. Chemoproteomic studies enabled the profiling of >300 endogenous kinases, thus providing a global landscape of ligandable catalytic lysines of the kinome. By further introducing these aminophiles into VX‐680 (a noncovalent inhibitor of AURKA kinase), we generated novel lysine‐reactive TCIs that exhibited excellent in vitro potency and reasonable cellular activities with prolonged residence time. Our work serves as a general guide for the development of lysine‐reactive ArOSO2F‐based TCIs. [ABSTRACT FROM AUTHOR]

Excellent morphology and low harmful defect states of the absorber layer are essential to fabricate the high‐performance Cu2ZnSn(S, Se)4 (CZTSSe) devices. Herein, the annealing time of precursor films in air is proved to have much impact on the quality of absorber layer and the performance of devices. Appropriately extending the air‐annealing time can promote the diffusion of Na into films and O absorption on the surface of precursor films, boost the growth of crystal grain, and lessen the harmful defect density and band‐tailing states of absorber. The appropriate extension of air‐annealing time also regulates the electrical properties of the absorber. The efficiency of CZTSSe devices is enhanced from 6.92% (1 min) to 10.1% (7 min), with the decreased VOC, Def. These enhanced properties demonstrate that regulating the air‐annealing time of precursor films can be a simple and direct way for improving the performance of CZTSSe devices. [ABSTRACT FROM AUTHOR]

Herein, the isothermal and continuous cooling transformation mechanisms of prior austenite and its relationship to fracture behavior of high‐strength medium‐Mn steel are studied. Furthermore, the precipitation behavior of cementite is also analyzed. The results indicate that the short rod‐like cementite forms in the martensite matrix during the air‐cooling process, the solubility difference of supersaturated elements provides a driving force for the element diffusion. Accordingly, it is proved that no isothermal transformation of prior austenite occurs during the 360 °C × 7 days isothermal treatment. The lath‐like microstructure is the martensite, which is produced during the subsequent continuous cooling process. The prior austenite is "divided" by the preferential martensite (transformed via heterogeneous nucleation), and the interfaces between preferential martensite and untransformed austenite provide nucleation sites for the subsequent martensite. The introduction of initial martensite before the isothermal treatment leads to the reversible brittleness of medium‐Mn steel. The fracture strength decreases with the increase of the initial martensitic fraction and isothermal time. The grain boundary binding force of prior austenite grains (PAGs) increases in the experimental steels subjected to annealing, and the plastic deformation of the martensite matrix is prior to grain boundary cracking, which inhibits the intergranular brittle fracture. [ABSTRACT FROM AUTHOR]

Semitransparent perovskite solar cells (ST‐PSCs) are highly promising for application in building‐integrating photovoltaics (BIPVs) due to their potential in tunable transparency and color. However, the comprehensive performance of ST‐PSCs falls quite short of the ideal requirements for BIPV. Herein, more attention is to review how to balance transparency and power conversion efficiency for ST‐PSCs. Optimizing transparent electrodes and the active layers are interesting strategies to achieve the transparency required by devices. In addition, to obtain color ST‐PSCs, tuning the bandgap of perovskite layers and designing the optical structure of the electrode are effective strategies. Last but not least, three significant optical evaluation indexes of ST‐PSCs are described in the supporting information: average visible transmittance, color rendering index, and light utilization efficiency. [ABSTRACT FROM AUTHOR]

Extra cation incorporations have been proved to enhance the properties of Cu2ZnSn(S, Se)4 materials, and help to obtain high‐efficiency solar cells. In this work, the authors study the influence of the extra tiny Mg2+ doping on the properties of Cu2ZnSn(S, Se)4 films. Through tuning the amount of Mg into the precursor solution, the crystallization, morphology, light absorption, and electrical properties all have been improved and can reach the optimum at 3% Mg‐doping, which is in favour of high‐performance CZTSSe devices. The authors' finding also demonstrates Mg element can be regarded as the new candidate for extra cation incorporations. [ABSTRACT FROM AUTHOR]

Despite recent interests in developing lysine‐targeting covalent inhibitors, no general approach is available to create such compounds. We report herein a general approach to develop cell‐active covalent inhibitors of protein kinases by targeting the conserved catalytic lysine residue using key SuFEx and salicylaldehyde‐based imine chemistries. We validated the strategy by successfully developing (irreversible and reversible) covalent inhibitors against BCR‐ABL kinase. Our lead compounds showed high levels of selectivity in biochemical assays, exhibited nanomolar potency against endogenous ABL kinase in cellular assays, and were active against most drug‐resistant ABL mutations. Among them, the salicylaldehyde‐containing A5 is the first‐ever reversible covalent ABL inhibitor that possessed time‐dependent ABL inhibition with prolonged residence time and few cellular off‐targets in K562 cells. Bioinformatics further suggested the generality of our strategy against the human kinome. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells (FPSCs) with high efficiency and excellent mechanical flexible properties have attracted enormous interest as a promising photovoltaic technology in recent years. However, the performance or stability of FPSCs is still far inferior to that of conventional glass‐based perovskite solar cells (PSCs). Herein, a cross‐linking agent called aluminum acetylacetonate (Al(acac)3) is introduced as an interface layer between electron transport layer and perovskite absorber. Due to the well‐matched energy levels and improved grain size and crystallinity of the perovskite, a champion device with the highest power conversion efficiency (PCE) of 20.87% is achieved on the FPSCs. The device retains about 80% of its initial performance after 1000 h under >50% relative humidity without encapsulation. In addition, attributed to the Al(acac)3 super bending resistance, more than 91% of the original PCE is retained after 1500 bending cycles. This work proposes the substrate side optimization for improving device efficiency and stability which may provide a novel concept for promoting the development of FPSCs. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHAs) are polyesters that can be biologically synthesized by many microorganisms and engineered plants that have been investigated by microbiologists, biochemists, polymer scientists, material engineers, and medical researchers for several decades. Research on microbial production of PHAs has been extensively focused on using pure carbon sources, such as sugars and fatty acids. Practical considerations of production costs of PHAs have resulted in research efforts to use alternative renewable and inexpensive feedstocks. One potential feedstock for the production of PHA polymers is the glycerol waste byproduct of biodiesel production. The major focus of this review is the production of PHA polymers from glycerol. A review of biosynthetic pathways for PHAs production from glycerol, current production of waste glycerol in biodiesel industry, physical and mechanical properties of PHAs, and applications of PHAs in the areas of packaging industry, implant materials, drug carrier, biofuels, are covered. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Glycerol, a byproduct of the biodiesel industry, can be used by bacteria as an inexpensive carbon source for the production of value-added biodegradable polyhydroxyalkanoates (PHAs). Burkholderia cepacia ATCC 17759 synthesized poly-3-hydroxybutyrate (PHB) from glycerol concentrations ranging from 3% to 9% (v/v). Increasing the glycerol concentration results in a gradual reduction of biomass, PHA yield, and molecular mass (Mn and Mw) of PHB. The molecular mass of PHB produced utilizing xylose as a carbon source is also decreased by the addition of glycerol as a secondary carbon source dependent on the time and concentration of the addition. 1H-NMR revealed that molecular masses decreased due to the esterification of glycerol with PHB resulting in chain termination (end-capping). However, melting temperature and glass transition temperature of the end-capped polymers showed no significant difference when compared to the xylose-based PHB. The fermentation was successfully scaled up to 200 L for PHB production and the yield of dry biomass and PHB were 23.6 g/L and 7.4 g/L, respectively. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [ABSTRACT FROM AUTHOR]