This study is the first to demonstrate that ferroelectric R3c LiNbO3‐type ZnSnO3 nanowires (NWs), through the piezocatalysis and piezophototronic process, demonstrate a highly efficient hydrogen ...evolution reaction (HER). The polarization and electric field curves indicate that ZnSnO3 NWs exhibit typical ferroelectric hysteresis loops. Time‐resolved photoluminescence spectra reveal that the relaxation time increases with the increasing concentration of oxygen vacancies. Moderated 3H‐ZnSnO3 NWs (thermally annealed for 3 h in a hydrogen environment) have the longest extended carrier lifetime of approximately 8.3 ns. The piezoelectricity‐induced HER, via the piezocatalysis process (without light irradiation), reaches an optimal H2‐production rate of approximately 3453.1 µmol g−1 h−1. Through the synergistic piezophototronic process, the HER reaches approximately 6000 µmol g−1 in 7 h. Crucially, the mechanical force–induced spontaneous polarization functions as a carrier separator, driving the electron and hole in opposite directions in ferroelectric ZnSnO3 NWs; this separation reduces the recombination rate, enhancing the redox process. This theoretical analysis indicates that the photocatalytic and piezocatalytic effects can synergistically enhance piezophototronic performance through capitalizing on well‐modulated oxygen vacancies in ferroelectric semiconductors. This study demonstrates the essential role of this synergy in purifying water pollutants and converting water into hydrogen gas through the piezophototronic process.
The well‐controlled oxygen vacancies of ferroelectric R3c ZnSnO3 nanowires show that a highly efficient hydrogen evolution reaction (HER) reaches approximately 6000 mol g−1 in 7 h through the synergistic piezophototronic process. This is the first study to investigate how the oxygen vacancy concentration can be tuned in ferroelectric crystals to enhance the performance of piezodegradation and HER through the piezophotoelectric effect.
Linear copolymer hosts bearing a number of pillar5arene dangling side chains are synthesized for the facile construction of highly emissive supramolecular polymer networks (SPNs) upon noncovalently ...cross‐linking with a series of tetraphenyethylene (TPE)‐based tetratopic guests terminated with different functional groups through supramolecular host–guest interactions. An extremely high fluorescence quantum yield (98.22%) of the SPNs materials is obtained in tetrahydrofuran (THF) by fine‐tuning the parameters, and meanwhile supramolecular light‐harvesting systems based on spherical supramolecular nanoparticles are constructed by interweaving 9,10‐distyrylanthracene (DSA) and TPE‐based guest molecules of aggregation‐induced emission (AIE) with the copolymer hosts in the mixed solvent of THF/H2O. The present study not only illustrates the restriction of the intramolecular rotations (RIR)‐ruled emission enhancement mechanism regulated particularly by macrocyclic arene‐containing copolymer hosts, but also suggests a new self‐assembly approach to construct high‐performance light‐harvesting materials.
Supramolecular polymer networks and supramolecular nanoparticles based on copolymer hosts bearing a number of pillar5arene dangling side chains and tetraphenyethylene‐based tetratopic guests are fabricated, incorporating high fluorescence quantum yield, tunable emission wavelength, and stable microstructures. This facile strategy suggests a new self‐assembly approach to construct high‐performance light‐harvesting materials.
Tubulin post-translational modifications (PTMs) occur spatiotemporally throughout cells and are suggested to be involved in a wide range of cellular activities. However, the complexity and dynamic ...distribution of tubulin PTMs within cells have hindered the understanding of their physiological roles in specific subcellular compartments. Here, we develop a method to rapidly deplete tubulin glutamylation inside the primary cilia, a microtubule-based sensory organelle protruding on the cell surface, by targeting an engineered deglutamylase to the cilia in minutes. This rapid deglutamylation quickly leads to altered ciliary functions such as kinesin-2-mediated anterograde intraflagellar transport and Hedgehog signaling, along with no apparent crosstalk to other PTMs such as acetylation and detyrosination. Our study offers a feasible approach to spatiotemporally manipulate tubulin PTMs in living cells. Future expansion of the repertoire of actuators that regulate PTMs may facilitate a comprehensive understanding of how diverse tubulin PTMs encode ciliary as well as cellular functions.
Aqueous zinc ion batteries (AZIBs) show a great potential for next‐generation energy storage due to their high safety and high energy density. However, the severe side reactions of zinc negative ...electrode largely hinder the further application of AZIBs. Herein, trace tris(hydroxymethyl)aminomethane (Tris) additive with rich lone‐pair‐electrons and zincophilic sites is firstly introduced to achieve long‐term and highly reversible Zn plating/stripping. Specifically, Tris not only regulates the solvation structure of Zn2+, but is also adsorbed vertically on the Zn anode surface with a changed coordination intensity during the plating/stripping process of Zn to generate an in situ dynamic adsorption layer for the first time. The dynamic adsorption layer could successively attract the solvated Zn2+ and then promote the de‐solvation of the solvated Zn2+ owing to the orientation polarization with regularly‐changed applied electric field, the volume rejection effect, and strong intermolecular force towards H2O of the vertically‐adsorbed Tris. Therefore, an improved Zn2+‐transport kinetics as well as the inhibition of side reactions of Zn anode are successfully realized. Accordingly, the Zn||Zn symmetric cell provides an ultra‐long cycle life of 2600 h. Furthermore, the Zn||MnO2 full cell with Tris could demonstrate a high capacity and structural stability for practical applications.
A dynamic anode/electrolyte interface coupled with regulated solvation structures strategy is firstly realized with Tris additive for aqueous zinc‐ion batteries. The dynamic adsorption layer could successively attract solvated‐Zn2+, then promote the de‐solvation by the orientation polarization, the volume rejection effect and strong intermolecular force of the vertically‐adsorbed Tris, leading to an improved Zn2+‐transport kinetics and the inhibition of side reactions.
Plant laccase (LAC) enzymes belong to the blue copper oxidase family and polymerize monolignols into lignin. Recent studies have established the involvement of microRNAs in this process; however, ...physiological functions and regulation of plant laccases remain poorly understood. Here, we show that a laccase gene, LAC4, regulated by a microRNA, miR397b, controls both lignin biosynthesis and seed yield in Arabidopsis. In transgenic plants, overexpression of miR397b (OXmiR397b) reduced lignin deposition. The secondary wall thickness of vessels and the fibres was reduced in the OXmiR397b line, and both syringyl and guaiacyl subunits are decreased, leading to weakening of vascular tissues. In contrast, overexpression of miR397b‐resistant laccase mRNA results in an opposite phenotype. Plants overexpressing miR397b develop more than two inflorescence shoots and have an increased silique number and silique length, resulting in higher seed numbers. In addition, enlarged seeds and more seeds are formed in these miR397b overexpression plants. The study suggests that miR397‐mediated development via regulating laccase genes might be a common mechanism in flowering plants and that the modulation of laccase by miR397 may be potential for engineering plant biomass production with less lignin.
The development of red thermally activated delayed fluorescence (TADF) emitters having excellent optoelectronic properties and satisfactory electroluminescence efficiency is full of challenges due to ...strict molecular design principles. Two red TADF molecules, 3‐(9,9‐dimethylacridin‐10(9H)‐yl)acenaphtho1,2‐bquinoxaline‐9,10‐dicarbonitrile and 3‐(2,7‐dimethyl‐10H‐spiroacridine‐9,9′‐fluoren‐10‐yl)acenaphtho1,2‐bquinoxaline‐9,10‐dicarbonitrile, are developed by adopting a donor–acceptor molecular architecture bearing an electron‐accepting acenaphtho1,2‐bquinoxaline‐9,10‐dicarbonitrile (ANQDC) moiety and a 9,9‐dimethyl‐9,10‐dihydroacridine or 2,7‐dimethyl‐10H‐spiroacridine‐9,9′‐fluorene electron donor. The combined effects of rigid and planar D/A moieties and highly steric hindrance between D and A groups endow both molecules with high rigidity to suppress nonradiative decay processes, resulting in high photoluminescence quantum efficiencies (ΦPLs) of up to 95%. Attributed to the linear and planar acceptor motif and rod‐like molecular configuration, both emitters achieve high horizontal ratios of emitting dipole orientation of ≈80%. The organic light‐emitting diodes (OLEDs) based on both emitters exhibit red emissions peaking at ≈615 nm and successfully afford ultrahigh electroluminescence performance with an external quantum efficiency of nearly 28% and a power efficiency of above 50 lm W−1, on par with the state‐of‐the‐art device efficiency for red TADF OLEDs. This presents a feasible design strategy for excellent TADF emitters simultaneously possessing high ΦPLs and horizontally aligned emitting dipoles.
An ultrahigh‐efficiency red thermally activated delayed fluorescence (TADF) OLED with an external quantum efficiency of nearly 28% and a power efficiency of exceeding 50 lm W−1 is realized. The OLEDs incorporate excellent red TADF emitters, simultaneously exhibiting 95% photoluminescence quantum efficiency and preferentially horizontal emitting dipole orientation.
This study evaluated risks of emergency room visit (ERV) for out-of-hospital cardiac arrest (OHCA) in 2005-2011, among patients with cardiologic and metabolic syndromes (CMS), in association with ...ambient environments.
Pooled and area-specific weather related cumulative six-day (lags 0 to 5) relative risks (RRs) and confidence intervals (CIs) of ERV for OHCA were evaluated for CMS cases, using distributed lag nonlinear models and multivariate meta-analytical second-stage model in association with the daily average temperatures and daily concentrations of air pollutants.
ERV risk increased as average temperature dropped to <27°C. At the mean temperature of 14°C, the cumulative six-day RRs of ERV were 1.73 (95% CI: 1.22, 2.46) for all OHCA patients, 1.74 (95% CI: 1.06, 2.84) for OHCA patients younger than 65 years old, and 1.99 (95% CI: 1.03, 3.81) for subjects with pre-existing hypertension. High temperature was also associated with elevated ERV of OHCA. Increased ERV risks in cases with pre-existing hypertension and diabetes mellitus were also associated with concentrations of air pollutants in northern Taiwan.
Our data provided evidences to clinicians, emerging medical services and public health that the ERV risk for OHCA patients is greater at low temperature than at high temperature. Patients with cardio and metabolic disorders need to pay greater attention to low temperature and avoid heat wave.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The hydroxide‐exchange membrane fuel cell (HEMFC) is a promising energy conversion device. However, the development of HEMFC is hampered by the lack of platinum‐group‐metal‐free (PGM‐free) ...electrocatalysts for the hydrogen oxidation reaction (HOR). Now, a Ni catalyst is reported that exhibits the highest mass activity in HOR for a PGM‐free catalyst as well as excellent activity in the hydrogen evolution reaction (HER). This catalyst, Ni‐H2‐2 %, was optimized through pyrolysis of a Ni‐containing metal‐organic framework precursor under a mixed N2/H2 atmosphere, which yielded carbon‐supported Ni nanoparticles with different levels of strains. The Ni‐H2‐2 % catalyst has an optimal level of strain, which leads to an optimal hydrogen binding energy and a high number of active sites.
Good support counts: Carbon‐supported nickel nanoparticles with an optimal level of strain are very active for the hydrogen oxidation and evolution reactions.
All‐inorganic CsPbX3 (X=I, Br, Cl) perovskite quantum dots (PQDs) have been investigated because of their optical properties, such as tunable wavelength, narrow band, and high quantum efficiency. ...These features have been used in light emitting diode (LED) devices. LED on‐chip fabrication uses mixed green and red quantum dots with silicone gel. However, the ion‐exchange effect widens the narrow emission spectrum. Quantum dots cannot be mixed because of anion exchange. We address this issue with a mesoporous PQD nanocomposite that can prevent ion exchange and increase stability. We mixed green quantum‐dot‐containing mesoporous silica nanocomposites with red PQDs, which can prevent the anion‐exchange effect and increase thermal and photo stability. We applied the new PQD‐based LEDs for backlight displays. We also used PQDs in an on‐chip LED device. Our white LED device for backlight display passed through a color filter with an NTSC value of 113 % and Rec. 2020 of 85 %.
Points of light: Green CsPbBr3 perovskite quantum dots (PQDs), embedded in mesoporous silica (MP), were mixed with red CsPb(Br0.4I0.6)3 quantum dots in a silicone resin and placed on an InGaN blue chip. The green and red QDs were excited by blue light with λ=450 nm. The resulting PQD white light emitting diode (LED) exhibits a wide color gamut because of its narrow emission wavelength.
Adaptive O-CNN Wang, Peng-Shuai; Sun, Chun-Yu; Liu, Yang ...
ACM transactions on graphics,
12/2018, Letnik:
37, Številka:
6
Journal Article
Recenzirano
We present an Adaptive Octree-based Convolutional Neural Network (Adaptive O-CNN) for efficient 3D shape encoding and decoding. Different from volumetric-based or octree-based CNN methods that ...represent a 3D shape with voxels in the same resolution, our method represents a 3D shape adaptively with octants at different levels and models the 3D shape within each octant with a planar patch. Based on this adaptive patch-based representation, we propose an Adaptive O-CNN encoder and decoder for encoding and decoding 3D shapes. The Adaptive O-CNN encoder takes the planar patch normal and displacement as input and performs 3D convolutions only at the octants at each level, while the Adaptive O-CNN decoder infers the shape occupancy and subdivision status of octants at each level and estimates the best plane normal and displacement for each leaf octant. As a general framework for 3D shape analysis and generation, the Adaptive O-CNN not only reduces the memory and computational cost, but also offers better shape generation capability than the existing 3D-CNN approaches. We validate Adaptive O-CNN in terms of efficiency and effectiveness on different shape analysis and generation tasks, including shape classification, 3D autoencoding, shape prediction from a single image, and shape completion for noisy and incomplete point clouds.
PDF
