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Owing to their attractive optical and chiroptical properties, chiral metal halide perovskites have received increasing attention, with potential applications ranging from photonics and optoelectronics to spintronics. Metal halide perovskite nanocrystals with either intrinsic or extrinsic (e.g., chiral ligand‐induced) chirality have been reported recently, and the interplay between these two types of chirality has yet to be addressed. Herein, the inversion and tuning of excitonic optical activity is reported in intrinsically chiral perovskite nanoplatelets, originating from interactions between their structural chirality (due to the spontaneously formed screw dislocations in the crystalline lattice) and the surface enantiomeric (R/S) chiral ligands R/S‐phenylethylammonium bromide. Through post‐preparative exposure of the perovskite nanoplatelets to these R/S ligands of varied contents, either chiral ligand‐induced intrinsic chirality inversion or negative and positive Cotton effects induced by the ligands via electronic coupling between the ligand and the nanoplatelets are identified. These findings deepen understanding of the modulation of excitonic optical activity in chiral perovskites and can guide the rational design and synthesis of novel chiral materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: Syngas to dimethyl oxalate (DMO) followed by hydrogenation to methyl glycolate (MG) is considered to be an environmentally friendly and economical route. However, the catalyst with super performance and low cost for this route is still challenging. In this work, a simple and low‐lost fabrication method was developed to prepare a Ru/activated carbon (AC) catalyst and was used for DMO hydrogenation to MG under mild reaction conditions. RESULTS: The Ru/AC catalyst showed the best performance in the low‐temperature hydrogenation of DMO to MG compared to Ru/SiO2 and Ru/Al2O3. A series of characterization results showed that the super catalytic properties of Ru/AC catalyst might be attributed to the higher dispersion of Ru on support and its smallest nanoparticles size, weak surface acidity and electron‐deficient state of Ru species. The key parameters such as Ru loading, temperature, weight hourly space velocity, and pressure, were comprehensively investigated. MG selectivity of 94.6% with DMO conversion of 97.2% were obtained over the 4.0 Ru/AC catalyst at 90 °C. The 4.0Ru/AC catalyst showed excellent stability and there was no obvious deactivation after 1032 h test. CONCLUSIONS: The Ru/AC catalyst is effective for the DMO hydrogenation to MG under mild conditions and has great promise for industrial applications because of its low cost, simple preparation, high efficiency, and long life. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Chiral semiconductor nanostructures have received enormous attention due to their emerging circularly polarized luminescence (CPL) properties. However, compared with well‐studied photoluminescence (PL), the reported CPL is much weaker and more challenging to be modulated. Herein, we describe a new approach for acquiring the intense and tunable CPL from inorganic chiral photonic crystals (CPCs) doped with semiconductor quantum dots (QDs). Unprecedentedly, the sign, position and intensity of CPL peaks can be precisely controlled by manipulating either the photonic band gap of CPCs or luminescence wavelength of QDs and a giant absolute dissymmetry factor |glum| up to 0.25 is obtained. More importantly, the origin of the CPL modulation is clearly elucidated by both experiment and theory. This work lays the foundation for the construction of next‐generation high‐performance CPL‐based devices. [ABSTRACT FROM AUTHOR]

Circularly polarized room‐temperature phosphorescence (CPRTP) is of paramount importance for applications in information encoding, bioimaging, and optoelectronic devices, however, it remains challenging to organize highly efficient CPRTP materials with controlled handedness and long afterglow. Herein, as an outstanding novel finding, it is diclosed that ultralong CPRTP with on‐demand chiroptical properties is simple to realize using the earth‐abundant cellulose and silica. It is shown that left‐handed chiral nematic nanoporous silica films featuring defect photoluminescence enable ultralong CPRTP with an unprecedented control of the handedness. This work presents that the chiral nematic nanoporous silica films display right‐handed CPRTP and left‐handed CPRTP with the phosphorescence dissymmetry factors up to −0.130 and 0.093 as well as the afterglow lifetimes of 1.094 and 0.949 s, respectively. The potential of the transparent chiral nematic nanoporous silica films, capable of ultralong CPRTP and selective reflection of left‐handed circularly polarized light, for the development of anticounterfeiting optical labels is showcased. This work presents a versatile strategy and a step toward the development of ultralong CPRTP materials with on‐demand chiroptical properties from readily available defect phosphors for photonic applications. [ABSTRACT FROM AUTHOR]

Developing angular trapping methods, which enable optical tweezers to rotate a micronsized bead, is of great importance for studies of biomacromolecules in a wide range of torque‐generation processes. Here a novel controlled angular trapping method based on model composite Janus particles is reported, which consist of two hemispheres made of polystyrene and poly(methyl methacrylate). Through computational and experimental studies, the feasibility to control the rotation of a Janus particle in a linearly polarized laser trap is demonstrated. The results show that the Janus particle aligned its two hemispheres interface parallel to the laser propagation direction and polarization direction. The rotational state of the particle can be directly visualized by using a camera. The rotation of the Janus particle in the laser trap can be fully controlled in real time by controlling the laser polarization direction. The newly developed angular trapping technique has the great advantage of easy implementation and real‐time controllability. Considering the easy chemical preparation of Janus particles and implementation of the angular trapping, this novel method has the potential of becoming a general angular trapping method. It is anticipated that this new method will significantly broaden the availability of angular trapping in the biophysics community. [ABSTRACT FROM AUTHOR]

Unfrozen water content significantly affects the thermal‐hydro‐mechanical characteristics of frozen soil. Currently, theoretical explanations for the presence of unfrozen water include capillary action, surface effects, adsorption forces, and the electrical double layer. However, the relationships between unfrozen water and these actions are not well explained, except for capillary forces. In addition, although frost heave experiments indicate that the electrical double‐layer solution on a clay particle contains the main portion of unfrozen water, the electrical double‐layer theory which produces a cation solution has not previously been used to calculate unfrozen water content. In this paper, it is assumed that the residual unfrozen water at very low temperatures (below −18°C) is held within the adsorption‐layer solution and that the remaining unfrozen water within the influence of surface effects is the cationic solution in the diffuse layer. Based on these assumptions, a theoretical model of unfrozen water is established with independent variables of temperature, specific surface area, and electrical double‐layer parameters. While the input parameters of the theoretical model are numerous and difficult to obtain, the theoretical model is simplified as a parametric model. Results of the parametric model are strongly consistent with experimental data within a certain temperature range, supporting the hypothetical conditions. The similarity in the underlying mathematical structure of the derived theoretical and parametric models to current semi‐empirical models further suggests that the surface effects of clay are the main causes of unfrozen water in frozen soil. Key Points: The presence of unfrozen water is explained by surface effects, adsorption forces, and the nature of the electrical double‐layer solutionThe surface effects are defined as the combined actions of molecules and negative charges on the clay surfaceThe residual unfrozen water is a stable adsorption‐layer solution [ABSTRACT FROM AUTHOR]

Qinghai Lake is the largest lake in China. However, its influence on the local climate remains poorly understood. By using an atmosphere‐lake coupled model, we investigated the impact of the lake on the local climate. After the adjustment of four key parameters, the model reasonably reproduced the lake‐air interaction. Superimposed by the orographic effects on lake‐land breeze circulation, the presence of the lake enhanced precipitation over the southern part of the lake and its adjacent land, while slightly reduced precipitation along the northern shore of the lake. The lake effect on local precipitation revealed a distinct seasonal and diurnal variability, reducing precipitation in May (−6.6%) and June (−4.5%) and increasing it from July (5.7%) to November (125.6%). During the open water season, the lake's daytime cooling effect weakened and the nighttime warming effect strengthened, affecting spatial distribution and intensity of lake‐induced precipitation. In early summer, precipitation slightly decreased over the north part of the lake due to the lake's daytime cooling. In turn, lake‐induced nighttime warming increased precipitation over the southern section of the lake and its adjacent land. With the start of the autumn cooling in September, heat and moisture fluxes from the lake resulted in precipitation increase in both daytime and nighttime over the entire lake. In October, the background atmospheric circulation coupled with the strong lake effects lead to a small amount but high proportion of lake‐induced precipitation spreading evenly over the lake. Key Points: The coupled lake‐atmosphere model after adjusting four key parameters performs well in quantifying the lake's regional climate effectsQinghai Lake decreased the local precipitation during April–June while increased that during July–NovemberThroughout the simulation period, precipitation declined slightly in the north and rose greatly in the south due to the lake's presence [ABSTRACT FROM AUTHOR]

Helping children recognize the distress of their victims and feel sympathy may facilitate the optimal socialization of ethical guilt. With a sample of 150 eight‐year‐olds, we tested the main and interactive relations of distress recognition and sympathy to ethical guilt after hypothetically stealing and pushing. Better fear recognition and higher sympathy were uniquely associated with higher ethical guilt. The link between fear recognition and ethical guilt was stronger in children with higher sympathy. Beyond their unique contributions, distress recognition and sympathy may work in concert to facilitate ethical guilt after harming others. Statement of contributionWhat is already known on this subjectChildren are thought to express more guilt if they recognize their victims' distress and feel sympathy for them.However, there is little evidence for the direct roles of distress recognition and sympathy in children's guilt, and none for their joint contribution.What the present study addsThe link between fear recognition and guilt was stronger in children with higher sympathy. Sympathy may help children harness and translate the awareness afforded by distress recognition into feelings of accountability and regret.This study was the first to clarify the main and additive roles of sympathy and distress recognition in children's anticipation of guilt after harming others.Promoting distress recognition and sympathy may represent a viable two‐step approach to inducing guilt in children after they violate others' welfare. [ABSTRACT FROM AUTHOR]

Neuroplastin 65 (Np65) is a brain‐specific cell adhesion molecule that is highly expressed in the hippocampus, amygdala, and cortex, regions of the brain that are associated with memory and emotions. However, the role of Np65 in regulation of emotional behavior is still unclear. In the present study, we show that Np65 knock‐out (Np65 KO) mice display enhanced anxiety‐like behavior, a reduction in some aspects of depressive‐like behaviors, and increased sociability and memory. Biochemical investigations revealed that Np65 KO mice show increased adult‐born neurons and proliferation in the hippocampus. In addition, the level of 5‐hydroxytryptamine (5‐HT) in the hippocampus was reduced. The expression of tryptophan hydroxylase 2 in the brainstem and the expression of the 5‐HT3A receptor were also decreased. Electrophysiological recordings confirmed an impaired maintenance of long‐term potentiation in the hippocampus of Np65 KO mice. Together, our findings uncover a role for Np65 in regulating anxiety‐ and depressive‐like behaviors and suggest that Np65 may be essential for the maintenance of emotional stability, indicating that it might be an attractive potential target for treatment of psychiatric disorders. [ABSTRACT FROM AUTHOR]

Inorganic single crystals with anisotropic structures usually suffer from high brittleness and stiffness. Flexible polymers are used to replace inorganic crystals, but the hot‐stretching‐induced orientation process is tedious, and oriented molecular chains tend to revert to random coils during aging. To overcome these obstacles and using the similarities between sub‐1 nm nanowires (NWs) and linear polymers, we successfully fabricated anisotropic, transparent, flexible, and stable (ATFS) NW films with great potential for optical applications through a wet‐spinning method. The NW films show birefringence, and their birefractive index is higher than that of many polymers. They also showed polarized absorption of UV light and anisotropic scattering of visible light. The integrated films composed of NWs and quantum dots showed good fluorescence polarization. The tedious synthesis of quantum rods and fabrication of oriented polymer films can thus be avoided. [ABSTRACT FROM AUTHOR]

The current study investigated the impact of birth weight on the ability to recognize facial expressions in adulthood among the longest known prospectively followed cohort of extremely low birth weight survivors (ELBW; <1,000 g). We measured perceptual threshold to detect subtle facial expressions and confusion among different emotion categories in order to disentangle visual perceptual ability from emotional processing. ELBW adults ( N = 64, Mage = 31.9 years) were more likely than normal birth weight (NBW) controls ( N = 82, Mage = 32.5 years) to see fear in angry faces. This finding was not a result of increased perceptual efficiency in processing fearful expressions in the ELBW adults, since the two groups did not differ on their threshold to detect emotion in low intensity facial expressions. These findings suggest that a processing bias toward fear may reflect long-term developmental effects from being born at ELBW that may portend socioemotional problems that characterize ELBW survivors. [ABSTRACT FROM AUTHOR]

An ultrastrong and broadband chiroptical response is key but remains challenging for many device applications. A simple and cost-effective bottom-up method is introduced to fabricate large-area long-range ordered chiral ultrathin films with the Langmuir-Schaeffer technique using gold nanowires as building blocks. Significantly, as-prepared ultrathin films display giant optical activity across a broad wavelength range covering visible and near infrared regions with an anisotropic factor of up to 0.285, which is the record value for bottom-up techniques. Detailed experimental result and theoretical analysis disclose that such remarkable optical activity originates from birefringence and dichroism of the well-aligned Au nanowire layers in the ultrathin films. The universality of this facile strategy for constructing chiral ultrathin films is further demonstrated with many other one-dimensional nanomaterials. [ABSTRACT FROM AUTHOR]

A new method for the heterogeneous synthesis of ethanolamide from soybean oil methyl ester and monoethanolamine/diethanolamine has been established by using CaO and modified CaO as the solid basic catalyst. As the results show, the commercial CaO catalyst gives a high yield (80.2%) of monoethanolamide with high purity at a ratio of methyl ester to amine of 1: 2 after 3 h under the reaction temperature of 130°C over modified CaO. The yield was greatly enhanced to 96.3% after commercial CaO was modified by benzyl bromide in a simple way. Moreover, this catalyst shows a promising future in providing an environmentally clean process for the industrial applications. The effects of modification and reaction conditions on yields as well as the possible reaction mechanism were discussed. Further investigation indicated that the structure of ethanolamine has a great effect on the yield of monoethanolamide. [ABSTRACT FROM AUTHOR]

Highlights Although 3D printing technology has been widely applied in fabrication of polymer composite, yet, it still exhibits low mechanical performance, restricting its application in structural materials. Herein, a new 3D printing polymer composite composed of carbon fiber and polyamide12 (PA12) is fabricated and subsequently treated by microwave treatment. It is found that the tensile strength and modulus of 3D printing CF/PA12 composite with microwave treatment are improved by 23.8% and 10.2% compared with the original specimen, respectively. Moreover, a new mechanism of mechanical reinforcement is investigated and proposed by nanoindentation and 3D X‐ray computed tomography. The work does not only confirm formation of 3D printing CF/PA12 composite with good mechanical properties, but also proposes a new mechanism of microwave treatment effect on 3D printing polymer composite based on carbon fiber. A new 3D printing CF/PA12 composite based on microwave treatment is developed. The 3D printing composite exhibits good mechanical properties. A new mechanism of mechanical reinforcement is proposed. [ABSTRACT FROM AUTHOR]