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Photoreduction of CO2with water into chemical feedstocks of fuels provides a green way to help solve both the energy crisis and carbon emission issues. Metal–organic frameworks (MOFs) show great potential for CO2photoreduction. However, poor water stability and sluggish charge transfer could limit their application. Herein, three water-stable MOFs functionalized with electron-donating methyl groups and/or electron-withdrawing trifluoromethyl groups are obtained for the CO2photoreduction. Compared with UiO-67-o-CF3–CH3and UiO-67-o-(CF3)2, UiO-67-o-(CH3)2achieves excellent performance with an average CO generation rate of 178.0 μmol g–1h–1without using any organic solvent or sacrificial reagent. The superior photocatalytic activity of UiO-67-o-(CH3)2is attributed to the fact that compared with trifluoromethyl groups, methyl groups could not only elevate CO2adsorption capacity and reduction potential but also promote photoinduced charge separation and migration. These are evidenced by gas physisorption, photoluminescence, time-resolved photoluminescence, electrochemical impedance spectroscopy, transient photocurrent characteristics, and density functional theory calculations. The possible working mechanisms of electron-donating methyl groups are also proposed. Moreover, UiO-67-o-(CH3)2demonstrates excellent reusability for the CO2reduction. Based on these results, it could be affirmed that the strategy of modulating substituent electronegativity could provide guidance for designing highly efficient photocatalysts.

Transition metal-peroxide complexes play a crucial role as intermediates in oxidation reactions. To unravel the mechanism of benzaldehyde oxidation by the Co-peroxo complex, we conducted density functional theory (DFT) calculations. The identified competing mechanisms include nucleophilic attack and hydrogen atom transfer (HAT). The nucleophilic attack pathway involves Co–O cleavage and nucleophilic attack, leading to the formation of the benzoate product. And the HAT pathway comprises O–O cleavage and HAT, ultimately resulting in the benzoate product. DFT calculations revealed that the formation of the end-on Co-superoxo complex 2through Co–O cleavage, starting from the side-on Co-peroxo complex 1, is much more favorable than the formation of the two-terminal oxyl-radical intermediate 3through O–O cleavage. Compared with the nucleophilic attack of benzaldehyde by 2, the abstraction of a hydrogen atom from benzaldehyde by 3requires higher energy. The nature of the nucleophilicity of 2and 3accounts for the reactivity of the reaction.

This study presents the rare examples of S-heteroaryl tetradentate Pt(S^C^N^O) luminescent complexes (PtSZand PtSZtBu) containing a Pt–S bond. The presence of the Pt–S bond allows the novel Pt(S^C^N^O) complexes to exhibit temperature-dependent phosphorescent emission behavior. The PtSZtBuexhibits dual-emission phenomena and biexponential transient decay spectra above 250 K, indicating the presence of two minimal excited states in the potential energy surface (PES) of the T1state. Through complementary experimental and computational studies, we have identified changes in orbital composition between Pt(dxy)–S(px) and Pt(dyz)–S(pz) in excited states with increasing temperature. This results in two energy minima, enabling the excited states to decay selectively and radiatively at different temperatures. Consequently, this leads to remarkable steady-state and transient emission spectra changes. Our work not only provides valuable insights for the development of novel Pt–S bond-based tetradentate Pt(II) complexes but also enhances our understanding of the distinctive properties governed by the Pt–S bond.

An enantioselective Pd-catalyzed intramolecular dearomative reductive Heck reaction of N-(o-bromoaryl) indole-3-carboxamide is developed. By employing Pd(dba)2/SPINOL-based phosphoramidite as the chiral catalyst and HCO2Na as the hydride source, a series of enantioenriched spiro indolines bearing vicinal stereocenters were afforded in moderate to good yields with excellent enantioselectivities. The reductive Heck reaction of formal tetrasubstituted alkene bearing β-hydrogens is therefore realized by inhibiting β-H elimination.

A demethylenative En-Yne radical cyclization of 1,7-enynes has been successfully developed to chemoselectively afford 3,4-dihyroquinolin-2-ones or quinolin-2-ones under the catalysis of Cu(I) photosensitizers PS3and PS6with different redox potentials. The preliminary mechanistic experiments revealed that the reaction underwent an unprecedented olefin-α-amino radical metathesis-type process. A reasonable mechanism was proposed to illustrate the catalyst-controlled chemoselectivity of the reaction based on preliminary mechanistic experiments and DFT calculations.

Ultraviolet organic light-emitting diodes (UV OLEDs) have attracted increasing attention because of their promising applications in healthcare, industry, and agriculture; however, their development has been hindered by the shortage of robust UV emitters. Herein, we embedded double boron–oxygen units into nonlinear polycyclic aromatic hydrocarbons (BO-PAHs) to regulate their molecular configurations and excited-state properties, enabling novel bent BO-biphenyl (BO-bPh) and helical BO-naphthyl (BO-Nap) emitters with hybridized local and charge-transfer (HLCT) characteristics. They could be facilely synthesized in gram-scale amounts via a highly efficient two-step route. BO-bPhand BO-Napshowed strong UV and violet-blue photoluminescence in toluene with full width at half-maximum values of 25 and 37 nm, along with quantum efficiencies of 98 and 99%, respectively. A BO-bPh-based OLED showed high color purity UV electroluminescence peaking at 394 nm with Commission Internationale de l’Eclairage (CIE) coordinates of (0.166, 0.021). Moreover, the device demonstrated a record-high maximum external quantum efficiency (EQE) of 11.3%, achieved by successful hot exciton utilization. This work demonstrates the promising potential of double BO-PAHs as robust emitters for future UV OLEDs.

A series of novel tetradentate 6/6/6 Pt(II) complexes containing an 8-phenylquinoline-benzo[d]imidazole-carbazole ligand was designed; the Pt(II) complexes could be synthesized by metalizing the corresponding ligand with K2PtCl4in high isolated yields of 60–90%. Experimental and theoretical studies suggested that the ligand modification of the quinoline moieties of the Pt(II) complexes could tune their electrochemical, photophysical, and excited-state properties. Notably, all the Pt(II) complexes exhibited highly electrochemical stabilities with reversible redox processes except the quasi-reversible reduction of PtYL3. The large π-conjugation of the ligand together with increased metal-to-ligand charge-transfer (3MLCT) characters in T1states enabled the Pt(II) complexes to show broad Gaussian-type NIR emission spectra with high photoluminescence quantum efficiencies of 1.2–1.5% and short τ of 0.8–1.5 μs in dichloromethane at room temperature. This work should provide a valuable reference for the design and development of monomer NIR emitters.

Quasi-classical molecular dynamics (MD) simulations were carried out to study the mechanism of iron porphyrin-catalyzed hydroxylation of ethylbenzene. The hydrogen atom abstraction from ethylbenzene by iron-oxo species is the rate-determining step, which generates the radical pair of iron-hydroxo species and the benzylic radical. In the subsequent radical rebound step, the iron-hydroxo species and benzylic radical recombine to form the hydroxylated product, which is barrierless on the doublet energy surface. In the gas-phase quasi-classical MD study on the doublet energy surface, 45% of the reactive trajectories lead directly to the hydroxylated product, and this increases to 56% in implicit solvent model simulations. The percentage of reactive trajectories leading to the separated radical pair is 98–100% on high-spin (quartet/sextet) energy surfaces. The low-spin state reactivity dominates in the hydroxylation of ethylbenzene, which is dynamically both concerted and stepwise, since the time gap between C–H bond cleavage and C–O bond formation ranges from 41 to 619 fs. By contrast, the high-spin state catalysis is an energetically stepwise process, which has a negligible contribution to the formation of hydroxylation products.

Improving the self-efficacy of intensive care unit nurses for delirium care could help them adapt to the changing situation of delirium patients. Validated measures of nurses' self-efficacy of delirium care are lacking

The optical and charge transport properties of organic semiconductors are strongly influenced by their morphology and molecular structures. Here we report the influence of a molecular template strategy on anisotropic control viaweak epitaxial growth of a semiconducting channel for a dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT)/para-sexiphenyl (p-6P) heterojunction. The aim is to improve charge transport and trapping, to enable tailoring of visual neuroplasticity. The proposed phototransistor devices, comprising a molecular heterojunction with optimized molecular template thickness, exhibited an excellent memory ratio (ION/IOFF) and retention characteristics in response to light stimulation, owing to the enhanced orientation/packing of DNTT molecules and a favorable match between the LUMO/HOMO levels of p-6P and DNTT. The best performing heterojunction exhibits visual synaptic functionalities, including an extremely high pair-pulse facilitation index of ∼206%, ultralow energy consumption of 0.54 fJ, and zero-gate operation, under ultrashort pulse light stimulation to mimic human-like sensing, computing, and memory functions. An array of heterojunction photosynapses possess a high degree of visual pattern recognition and learning, to mimic the neuroplasticity of human brain activities through a rehearsal learning process. This study provides a guide to the design of molecular heterojunctions for tailoring high-performance photonic memory and synapses for neuromorphic computing and artificial intelligence systems.

The present study referred to the technology-based learning model to conduct a systematic review of the dimensions of nursing activities, research samples, research methods, roles of artificial intelligence, applied artificial intelligence algorithms, evaluation measure of algorithms, and research foci. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses procedure, this study obtained and analyzed a total of 102 high-quality artificial intelligence–associated nursing activities studies published from 2001 to 2020 in the Web of Science database. The results showed: (1) In terms of nursing activities, nursing management was explored the most, followed by nursing assessment; (2) quantitative methods were most frequently adopted in artificial intelligence–associated nursing activities studies to investigate issues related to patients, followed by nursing staff; (3) the most adopted roles of artificial intelligence in artificial intelligence–associated nursing activities studies were profiling and prediction, followed by assessment and evaluation; (4) artificial intelligence–associated nursing activities studies frequently mixed applied artificial intelligence algorithms and evaluation measure of algorithms; (5) in the dimension of research foci, most studies mainly paid attention to the design or evaluation of the artificial intelligence systems/instruments, followed by investigating the correlation and affect issues. Based on the findings, several recommendations are raised as a reference for future researchers, educators, and policy makers.

We report here a regiospecific [3 + 2] annulation between aminocyclopropanes and various functionalized alkynes enabled by a P/N-heteroleptic Cu(I) photosensitizer under photoredox catalysis conditions. Thus, a divergent construction of 3-aminocyclopentene derivatives including methylsulfonyl-, arylsulfonyl-, chloro-, ester-, and trifluoromethyl-functionalized aminocyclopentenes could be achieved with advantages of high regioselectivity, broad substrate compatibility, and mild and environmentally benign reaction conditions.

With the explosive growth in data generation, phototransistor memory capable of multibit data storage with higher stability and switchability is highly desired to enhance the capacity of storage media. An innovative intrinsic dual-functional block copolymer (BCP)-based electret consisting of poly(ethylene oxide)-block-poly(1-pyrenemethyl methacrylate) (PEO-b-PPyMA) was used to elucidate the effect of the BCP design and self-assembled morphology on phototransistor memory. Regarding the constituent polymers in the BCP, PPyMA serves as the photogate, while PEO enhances the charge stability through electrostatic interaction. On the other hand, the solvent-annealed BCP film, representing well-defined hexagonal cylinders, shows an excellent charge trapping/stabilizing capability. Accordingly, the phototransistor memory, with PEO-b-PPyMA as an electret, produced a wide memory window (54 V), a superior memory stability (>106), and a fast photoresponsive characteristic. This research presents for the first time a new concept on the intrinsic dual-functional BCP to produce high-performance nonvolatile memory and demonstrates the potential of this approach for prospective application in optoelectronic devices.

The Cu2+ in the drinking water has a very serious impact on human health and social ecology. Many countries have the policy on the Cu2+ concentration limitation in drinking water and the industrial Cu2+ emission standards for the treated wastewater. Scientists have developed many methods to remove Cu2+ from wastewater. Among all the adsorption method is widely used due to its high efficacy, feasibility and low cost. The adsorbent is critical to achieving superior Cu2+ removal result. In this paper, Fe3O4/carbon-graphene oxide nanocomposites (Fe3O4@C-GO) were prepared by a hydrothermal method. The Fe3O4@C-GO is the main absorbent to Cu2+ through chemisorption. The specific surface area of Fe3O4@C-GO dramatically increases from 16 m2/g of Fe3O4@C to 62 m2/g, which expands the Cu2+ absorption capacity up to 350 mg/g. Fe3O4 nanoparticles with about 12 nm in diameter are uniformly encapsulated in the C-GO matrix, and therefore the Fe3O4@C-GO can be easily separated from the solution via magnetics. This adsorbent is also very easily recovered by an external magnetic field from the treated wastewater and has high reusability.

Background: Although most paediatric radial neck fractures can be treated with closed reduction, some severely displaced fractures require open reduction. The purpose of this study is to compare the effects of ESIN and KW fixation in open reduction of radial neck fracture in children. Methods: Twenty-four patients with mean age of 8.5 years were included. Four of the patients had a Judet type III fracture and 20 had a Judet type IV fracture. Ten patients who underwent percutaneous KW fixation were assigned to group A, while 14 patients who underwent ESIN fixation were assigned to group B. Variables of interest included age, sex, fracture type, associated lesions, surgical time, fracture reduction, cost, follow-up, healing time, X-rays, clinical outcomes, and complications. Results: There were no significant between-group differences in sex, age, additional injuries, fracture type, and quality of reduction. Costs were significantly lower in Group A. Fracture healing was achieved in 23 of 24 patients (10/10 in group A and 13/14 in group B). In a postoperative elbow function assessment based on the Steele and Graham classification, 80% of patients in group A had a score of excellent or good, compared to 78.6% of patients in group B. Two cases of nail shifting and joint protrusion were observed in group B, one of which also presented with nonunion during follow-up. Conclusions: Both KW and ESIN may achieve good clinical outcomes, but KW is associated with lower costs, easier implant removal (without the need for a secondary surgery), and lower iatrogenic complications.