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Multifunctional integration of optoelectronic devices within a single photodiode is in high demand for next‐generation on‐chip multifunctional integration and Internet of Things applications. Owing to the rapidity of nucleation‐crystallization that is associated with the solution method, large trap state densities (Nt), and consequently, severe dark current densities, as well as recombination losses are generally induced, which are detrimental to the detectivity (D*) of organic photodetectors (OPDs) and to the open‐circuit voltage (VOC) of organic photovoltaics (OPVs). Herein, a versatile p‐i‐n heterojunction organic photodiode with optimized vertical phase distribution and rational solid‐state packing is fabricated via a layer‐by‐layer (LBL) deposition procedure entailing the introduction of a rylene‐fullerene hybrid as a morphological modulator. This precisely controlled photodiode displayed suppressed Nt (2.5 × 1016 cm−3), low‐lying Urbach energy Eu (23.2 meV), as well as synergistically reduced series resistance, dark current, and sub‐bandgap radiative/non‐radiative recombination losses. Consequently, this ternary‐pseudo‐bilayer‐type photodiode exhibits excellent dual‐function performance with an outstanding D* of 9.48 × 1011 Jones in self‐powered OPD mode and a surprisingly suppressed energy loss of 0.538 eV in OPV mode. This study provides important insights into the mechanism and effects of trap density and energy disorder suppression in solution‐processed multifunctional integrated photoelectric conversion diodes. [ABSTRACT FROM AUTHOR]

There are two kinds of chlorites occurred in Anshan area, among which the hydrothermal Fe-chlorite with longer Fe-OH wavelength is spatially related to the high-grade magnetite ore, meaning that wavelength mapping of chlorites can be used to target the BIF-hosted high grade iron ore. In this article, quadratic polynomial, cubic spline, and quartic polynomial method were used to interpolate the absorption wavelength near 2250 nm of China ZY1-02D satellite hyperspectral image. The result of quadratic polynomial is continuous without data overlapping or intervals, thus most suitable for discrimination of the chlorites. The field truth shows that the spatial distribution of Fe-chlorite, validated by XRD analysis, is not only in accordance with that of high grade magnetite ore bodies, but also consistent with the recently discovered concealed iron bonanza. The study shows that hyperspectral remote sensing techniques can play significant role in the exploration of magnetite iron ore in east Liaoning Province. [ABSTRACT FROM AUTHOR]

Surface defects are crucial to perovskite single crystals (SCs) for versatile optoelectronic applications, whereas suffers from the intricate post‐treatments and unsatisfactory reproducibility within solution growth strategy due to the residue solvent corrosion and adsorbed precursors deposition. Here, an ionic liquid, 1‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (BMITFSI) is demonstrated, assisted solution growth approach for fabricating high‐quality self‐cleaning perovskite single crystals with no need for any post‐treatment. Benefiting from the in situ assembling in crystalline surface, BMITFSI can effectively decrease the crystallographic trap density by simultaneously introducing the self‐cleaning effect and optimizing the crystalline growth process. Particularly, as fabricated MAPbI3 single crystal exhibits an impressive photodetection performance with a specific detectivity of 2.83 × 1012 Jones in visible‐IR spectrum and a sensitivity of 7.24 × 104 µC Gyair−1 cm−2 in X‐ray detection, which is as good as the conventionally fabricated crystal with elaborate post‐treatments. Based on the chemical composition independent universality, this work paves an easy but efficient route to improve the current crystallization methodology toward high‐quality perovskite SCs fabrication. [ABSTRACT FROM AUTHOR]

A concisetotal synthesis of mersicarpine is achieved by exploitinga cyclic carbamate for generation of a tertiary carbocation. The keystep involves intramolecular Friedel–Crafts alkylation withthis carbocation for the construction of a quaternary carbon centerand a subsequent oxidation and cyclization cascade for the formationof a seven-membered cyclic imine. The chemistry allowed for a rapidone-pot synthesis of mersicarpine from a simple intermediate usingstraightforward chemical operations. [ABSTRACT FROM AUTHOR]

Abstract: A quick access to the core of dihydroindole alkaloid mersicarpine was developed based on straightforward transformations from readily available and inexpensive starting materials. The synthetic route features an aldol reaction, a Beckmann rearrangement for the synthesis of the δ-lactam, an intramolecular SNAr strategy for indoxyl heterocycle formation, and in situ autoxidation of indoxyl intermediate. The new strategy offered an alternative approach for the formation of an oxidized indoxyl moiety, which could potentially have a wider application in the total synthesis of indole alkaloids containing apparent or masked indoxyl moieties. [Copyright &y& Elsevier]

Terpene cyclization, one of the most complex chemical reactions in nature, is generally catalyzed by two classes of terpene cyclases (TCs). Cytochrome P450s that act as unexpected TC‐like enzymes are known but are very rare. In this study, we genome‐mined a cryptic bacterial terpenoid gene cluster, named ari, from the thermophilic actinomycete strain Amycolatopsis arida. By employing a heterologous production system, we isolated and characterized three highly oxidized eunicellane derived diterpenoids, aridacins A−C (1–3), that possess a 6/7/5‐fused tricyclic scaffold. In vivo and in vitro experiments systematically established a noncanonical two‐step biosynthetic pathway for diterpene skeleton formation. First, a class I TC (AriE) cyclizes geranylgeranyl diphosphate (GGPP) into a 6/10‐fused bicyclic cis‐eunicellane skeleton. Next, a cytochrome P450 (AriF) catalyzes cyclization of the eunicellane skeleton into the 6/7/5‐fused tricyclic scaffold through C2−C6 bond formation. Based on the results of quantum chemical computations, hydrogen abstraction followed by electron transfer coupled to barrierless carbocation ring closure is shown to be a viable mechanism for AriF‐mediated cyclization. The biosynthetic logic of skeleton construction in the aridacins is unprecedented, expanding the catalytic capacity and diversity of P450s and setting the stage to investigate the inherent principles of carbocation generation by P450s in the biosynthesis of terpenoids. [ABSTRACT FROM AUTHOR]

Terpene cyclization, one of the most complex chemical reactions in nature, is generally catalyzed by two classes of terpene cyclases (TCs). Cytochrome P450s that act as unexpected TC‐like enzymes are known but are very rare. In this study, we genome‐mined a cryptic bacterial terpenoid gene cluster, named ari, from the thermophilic actinomycete strain Amycolatopsis arida. By employing a heterologous production system, we isolated and characterized three highly oxidized eunicellane derived diterpenoids, aridacins A−C (1–3), that possess a 6/7/5‐fused tricyclic scaffold. In vivo and in vitro experiments systematically established a noncanonical two‐step biosynthetic pathway for diterpene skeleton formation. First, a class I TC (AriE) cyclizes geranylgeranyl diphosphate (GGPP) into a 6/10‐fused bicyclic cis‐eunicellane skeleton. Next, a cytochrome P450 (AriF) catalyzes cyclization of the eunicellane skeleton into the 6/7/5‐fused tricyclic scaffold through C2−C6 bond formation. Based on the results of quantum chemical computations, hydrogen abstraction followed by electron transfer coupled to barrierless carbocation ring closure is shown to be a viable mechanism for AriF‐mediated cyclization. The biosynthetic logic of skeleton construction in the aridacins is unprecedented, expanding the catalytic capacity and diversity of P450s and setting the stage to investigate the inherent principles of carbocation generation by P450s in the biosynthesis of terpenoids. [ABSTRACT FROM AUTHOR]

Through panel data for every province in China from 2006 to 2016, this paper studies the impact of the efficiency of science and technological services and the level of economic development on environmental governance, with the efficiency of science and technological services as the threshold variables. The results of the research indicate that the efficiency of science and technological services in China's provinces is low, while the regional gap is expanding. When the efficiency of science and technological services is the threshold variable, single threshold results are significant. When the efficiency of science and technological services is the threshold variable and when the efficiency of science and technological services is lower than the threshold value, there is a significant impact on environmental governance. If the efficiency of science and technological services crosses the threshold value, the impact of science and technological service efficiency on environmental governance becomes insignificant. For the level of economic development, it is a core explanatory variable and has a significant impact on environmental governance only when the efficiency of science and technological services is below the threshold value. According to the empirical results, this paper proposes corresponding countermeasures and suggestions. [ABSTRACT FROM AUTHOR]

The article presents a chemical structure for the article "Total Synthesis of Mersicarpine Through a Cationic Cyclization Approach" by G. Liang and colleagues published in the journal "Organic Letters" in a 2014 issue.

Covering: up to mid-2020 Terpenoids, also called isoprenoids, are the largest and most structurally diverse family of natural products. Found in all domains of life, there are over 80 000 known compounds. The majority of characterized terpenoids, which include some of the most well known, pharmaceutically relevant, and commercially valuable natural products, are produced by plants and fungi. Comparatively, terpenoids of bacterial origin are rare. This is counter-intuitive to the fact that recent microbial genomics revealed that almost all bacteria have the biosynthetic potential to create the C5 building blocks necessary for terpenoid biosynthesis. In this review, we catalogue terpenoids produced by bacteria. We collected 1062 natural products, consisting of both primary and secondary metabolites, and classified them into two major families and 55 distinct subfamilies. To highlight the structural and chemical space of bacterial terpenoids, we discuss their structures, biosynthesis, and biological activities. Although the bacterial terpenome is relatively small, it presents a fascinating dichotomy for future research. Similarities between bacterial and non-bacterial terpenoids and their biosynthetic pathways provides alternative model systems for detailed characterization while the abundance of novel skeletons, biosynthetic pathways, and bioactivies presents new opportunities for drug discovery, genome mining, and enzymology. [ABSTRACT FROM AUTHOR]

Converting the UV-blue irradiation into longer wavelength can efficiently ameliorate the insufficient solar spectral response and enhance the power conversion efficiency (PCE) of silicon solar cells, whereas there is still no appropriate strategy to make the corresponding luminescence downshifting materials compatible with commercial silicon photovoltaic modules practically. Herein, we first demonstrate an in-situ fabricated CsPbBr 3 PQDs/POE encapsulation adhesive film, which can simultaneously achieve continuously large-scale manufacture through melt extrusion and possess well compatibility with the encapsulation technique of silicon photovoltaic modules. According to the separate granulation preparation and technical optimization, the composited adhesive film exhibits an intensive PL emission at 515 nm with a full width at a half-maximum of 20 nm and an ultra high PLQY of 98.2%. Moreover, less than 5% PL intensity decline even after keeping in 50 °C/90 RH aging condition for >2400 h proves its excellent working stability and barrier property. By means of hot pressing operation, the silicon solar cells encapsulated with CsPbBr 3 PQDs/POE adhesive film harvest an absolute PCE enhancement of 0.68%. This work provides a way of great potential towards further improving the silicon photovoltaic industry and corresponding optoelectronic applications. • Proposing an in-situ manufacturing approach of CsPbBr 3 PQDs/POE encapsulation adhesive film. • Realizing the in-situ fabrication of PQDs in non-polar polymeric matrix. • Impressive luminescence down shifting effect of CsPbBr 3 PQDs/POE encapsulation adhesive film. • Achieving a 0.68% increment for the absolute PCE of silicon solar cells with CsPbBr 3 PQDs/POE adhesive film encapsulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A copolymer hydrogel was fabricated to harvest oceanic energy. • Ionic concentration was main driving force for continuous electricity generation. • This device produced a power density of 89.4 µW cm−2 in real seawater. • The series connection of six devices could power commercial electronic devices. Micro/nano fluidic electricity generation systems based on solid–liquid interface interaction to harvest energy from water in nature offer a potential green and clean electricity generation method. However, the performances of electricity generation were limited in salt solutions. In this paper, we prepared an extraordinary-performance hydrogel through ultraviolet polymerization for the access of ion concentration energy in seawater. This copolymer hydrogel made of AAm/AA (acrylamide/acrylic acid) provides a negatively charged three-dimensional transport network with micro/nano porous channels, which exhibits extraordinary ion selectivity in high ion concentration solutions. The experimental results show that this electricity generation device with intrinsic micro/nano pores can generate a continuous open-circuit voltage of 0.37 V, a short-circuit current of 116 μA, and a power density of 89.4 µW/cm2 from seawater (the Yellow Sea in China). The output current and power can be maximally more than 100 times and 50 times higher than the existing results. Through the series connection of six devices, the overall output is sufficient to supply stable power to directly light up small commercial electronic devices. Our study presents a new research idea for the development of low-cost, environmentally friendly, and self-powered devices. [ABSTRACT FROM AUTHOR]

• A decoupled establishing method of coordinates system of 3D shipboard crane systems. • The non-smooth dynamics of an 18-DOF series-parallel hybrid rigid-flexible coupling underactuated system. • Frequency spectrum, Poincaré map, and phase trajectories are used to analyze the characteristics. • Out-of-plane behavior, asymmetric oscillation, and weak chaos are found. • Experiments are performed to validate the dynamics and open-loop anti-swing performance. For heavy cargo swing suppression on offshore boom cranes, a cable-driven series-parallel hybrid double-mass active anti-swing mechanism is proposed, which is a typical non-smooth coupled oscillator. To facilitate the study of dynamic characteristics of the system, the cargo swings were decomposed into two decoupled swings. Then, the kinematics is built using the influence coefficient principle. Considering the longitudinal vibration, cables were regarded as piecewise spring-damping systems. Subsequently, an 18-DOF non-smooth dynamic model with actuators was obtained. Additionally, the influence of the floating platform's excitations and the system's initial state on responses was investigated by numerical solution. Analysis tools such as the phase trajectory and Poincaré map were used to explore the dynamic characteristics, and the results exhibit the existence of out-of-plane behavior, secondary resonance, asymmetric oscillation, and chaos. Finally, experiments were performed to validate the dynamics and performance of an open-loop anti-swing method. This study will be significant for further research on anti-swing controllers. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases are one of the leading causes of death worldwide and cardiac fibrosis is a common pathological process for cardiac remodeling in cardiovascular diseases. Cardiac fibrosis not only accelerates the deterioration progress of diseases but also becomes a pivotal contributor for futile treatment in clinical cardiovascular trials. Although cardiac fibrosis is common and prevalent, effective medicines to provide sufficient clinical intervention for cardiac fibrosis are still unavailable. Traditional Chinese medicine (TCM) is the natural essence experienced boiling, fry, and other processing methods, including active ingredients, extracts, and herbal formulas, which have been applied to treat human diseases for a long history. Recently, research has increasingly focused on the great potential of TCM for the prevention and treatment of cardiac fibrosis. Here, we aim to clarify the identified pro-fibrotic mechanisms and intensively summarize the application of TCM in improving cardiac fibrosis by working on these mechanisms. Through comprehensively analyzing, TCM mainly regulates the following pathways during ameliorating cardiac fibrosis: attenuation of inflammation and oxidative stress, inhibition of cardiac fibroblasts activation, reduction of extracellular matrix accumulation, modulation of the renin-angiotensin-aldosterone system, modulation of autophagy, regulation of metabolic-dependent mechanisms, and targeting microRNAs. We also discussed the deficiencies and the development direction of anti-fibrotic therapies on cardiac fibrosis. The data reviewed here demonstrates that TCM shows a robust effect on alleviating cardiac fibrosis, which provides us a rich source of new drugs or drug candidates. Besides, we also hope this review may give some enlightenment for treating cardiac fibrosis in clinical practice. [Display omitted] • Fibrosis is a fundamental process during cardiac remodeling and associated with adverse outcomes. • To date, effective therapeutic interventions for cardiac fibrosis are still lacking. • TCM targets multiple mechanisms and pathways in the fibrotic process to relieve cardiac fibrosis. • TCM provides us a rich source of new drugs or drug candidates for cardiac fibrosis. [ABSTRACT FROM AUTHOR]