Multi‐degree orthogonal manipulation of light, especially the on‐demand tailoring of the working band and spatial phase front, is expected to fully exhibit the superiority of photons as information ...carriers. In article number 2200153 by Xiao Liang, Wei Hu, and co‐workers, recent progresses on helical liquid crystal planar optics with customizable working band are reviewed. The new elements will boost the capability of information transporting and data processing.
Orthogonal manipulation of multi‐dimensional parameters of light is urgently desired in high‐speed processing and reliable transmission of massive information. In article number 2201088, Zhi‐Gang ...Zheng, Yan‐Qing Lu, Wei Hu and co‐workers present a heliconical cholesterics‐based spatial phase modulator with electrically customizable working frequency. The device simultaneously manipulates the spatial phase and wavelength/frequency of light via photoaligning the initial orientation of the liquid crystal and electrically varying the pitch of the heliconical superstructure, respectively. It supplies a platform for multidimensional planar optics that may upgrade existing optical informatics.
A new bromethyl-substituted molecular rotor, Cu（dabcoCH2Br）（H2O）Br3 （dabcoCH2Br＋=1-（2-bromethyl）-1,4-diazoniabi- cyclo2.2.2octane cation）, which belongs to a family of balomethyl-substituted ...molecular rotors, was synthesized and struc- turally characterized. The reversible phase transition at ca. 250 K was well established for this molecular rotor by thermal analyses, variable-temperature X-ray diffraction, and variable temperature dielectric measurements. The order-disorder trans- formation of the rotator part （dabco moiety） causes ferroelastic phase transition with an Aizu notation of mmmF2/m from high- temperature orthorhombic phase （Pbnm） to low-temperature monoclinic phase （P21/n）. More important, in reference to the density functional theory calculations and structural analyses, the key factors to tune the phase transition behaviors were dis- cussed in detail for this family of halomethyl-substituted molecular rotors.
Background： Little is known about the long-term outcomes of severe acute respiratory distress syndrome （ARDS） patients requiring extracorporeal membrane oxygeuation （ ECMO）. This study aimed Io ...investigate the 1 -year outcomes of these patients or patients receiving mechanical ventilation （MV） and compare their health-related quality of lili： （HRQoL） to the general population. Methods： Severe ARDS survivors admitted to two ICUs in China between .lanuary 2012 and .lanuary 2014 were enrolled. Of the severe ARDS survivors enrolled, 1-year postdischarge, HRQoL assessment using the Short-Forna 36 （SF-36） and EuroQol questionnaire dimensions, 6-rain walking distance, chest computed tomography scan, pulmonary limction, and arterial blood gas analysis were compared lbrARDS patients with or without ECMO. Rcsulls： ARDS patients receiving ECMO had a significantly higher Acute Physiology and Chronic Health Evaluation 11 score （30.3 ± 6.7 vs. 26.5 ± 7.3, P = 0.036）, lung injury score （3.3 ± 0.4 vs. 2.8 ± 0.5, P = 0.000）, Sequential Organ Failure Assessment score （ 10.8 ± 3.5 vs. 7.9 ＋ 3.1, P = 0.000）, lower PaO,/FiO, ratio （mmHg, 1 namHg = 0.133 kPa, 68.3 ± 16.1 vs. 84.8 ± 16.5, P = 0.000）, and increased extrapuhnonary organ Iiailure （2 1, 3 vs. 1 1, 1, P - 0.025） compared with patients not receiving ECMO. ECMO and non-ECMO survivors showed similar pulmonary fimction, morphological abnormalities, resting arterial blood gas wflues, and 6-rain walking distance. Mild pulmonary dyslimction and abnormal morphology were observed in a few survivors. In addition, ECMO and non-ECMO survivors showed a similar quality of life. ECMO survivors showed lower SF-36 physical functioning and role-physical domain scores （minimum clinically significant difference at least 5 points）, and non-ECMO survivors had similar outcome. Conclusions： One-year posthospital discharge, severe ARDS survivors receiving ECMO or MV demonstrated comparable outcomes. Compared with the general population, ARDS survivors showed reduced HRQoL. Pulmonary function and hmg morphology revealed sufficient recovery with minor lung impainnent.
Separation of oil/water mixtures, especially for the emulsified oil/water mixtures, is important because of the frequent occurrence of oil spill accidents. Utilizing superwetting porous membrane has ...become a promising approach to separate either surfactant-free or surfactant-stabilized emulsions. Herein we report a facile and versatile strategy for preparing hydrophobic/under-oil superhydrophobic membranes by coating the skeletons of the membranes with the poly（3,3,3- trifluoropropyl）methylsiloxane （PTFPMS） nanoparticles. The obtained membranes could be used to separate various water- in-oil emulsions with high flux and separation efficiency. In addition, owning to the outstanding resistance of PTFPMS to the most organic solvents or oils, the modified membranes exhibited the excellent reusability and the antifouling properties that were critical in the practical applications. Many commercially available membranes can be modified by such a simple method.
Two‐dimensional (2D) materials and ultrathin nanosheets are advantageous for elevating the catalysis performance and elucidating the catalysis mechanism of heterogeneous catalysts, but they are ...mostly restricted to inorganic or organic materials based on covalent bonds. We report an electrochemical/chemical exfoliation strategy for synthesizing metal–organic 2D materials based on coordination bonds. A catechol functionalized ligand is used as the redox active pillar to construct a pillared‐layer framework. When the 3D pillared‐layer MOF serves as an electrocatalyst for water oxidation (pH 13), the pillar ligands can be oxidized in situ and removed. The remaining ultrathin (2 nm) nanosheets of the metal–organic layers are an efficient catalyst with overpotentials as low as 211 mV at 10 mA cm−2 and a turnover frequency as high as 30 s−1 at an overpotential of 300 mV.
MOF slicing: A pillared‐layer metal–organic framework (MOF), in which the catechol functionalized pillars can be oxidized and removed in an electrochemical process, gives ultrathin nanosheets (2 nm). These are efficient electrocatalysts for water oxidation at pH 13 with a low overpotential and high turnover frequency (TOF).
The changeable molecular dynamics of flexible polar cations in the variable confined space between inorganic chains brings about a new type of two‐step nonlinear optical (NLO) switch with genuine ...“off–on–off” second harmonic generation (SHG) conversion between one NLO‐active state and two NLO‐inactive states.
A new perovskite‐like coordination polymer (CH3)2NH2Cd(N3)3 is reported which undergoes a reversible ferroelastic phase transition. This transition is due to varied modes of motion of the (CH3)2NH2+ ...guest accompanied by a synergistic deformation of the Cd(N3)3− framework. The unusual two‐staged switchable dielectric relaxation reveals the molecular dynamics of the polar cation guest, which are well controlled by the variable confined space of the host framework. As the material switches from the ferroelastic phase to the paraelastic phase, a remarkable increase of the rotational energy barrier is detected. As a result, upon heating at low temperature, this compound shows a notable change from a low to a high dielectric state in the ferroelastic phase. This thermoresponsive host–guest system may serve as a model compound for the development of sensitive thermoresponsive dielectric materials and may be key to understanding and modulating molecular/ionic dynamics of guest molecules in confined space.
Flexible frameworks: A perovskite‐like coordination polymer (CH3)2NH2Cd(N3)3 undergoes a ferroelastic‐to‐paraelastic phase transition as a result of the motion of the guest cation within the host framework (see picture), which itself undergoes a simultaneous deformation. This material acts as a thermoresponsive dielectric system owing to the well‐controlled guest molecular dynamics in the confined space.
Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non‐3d metal modulation strategy is presented ...for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks Co4(MO4)(eim)6 (M=Mo or W, Heim=2‐ethylimidazole) having Co(eim)3(MO4) units and high water stabilities were designed and synthesized. In different neutral media, the Mo‐modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm−2 at an overpotential of 210 mV in CO2‐saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm−2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non‐precious metal catalysts and even outperforms RuO2. Spectroscopic measurements and computational simulations revealed that the non‐3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate‐determining step to a more moderate value.
Non‐3D for 3D: Introducing non‐3d metal oxide units into a cobalt imidazolate framework results in the drastic enhancement of electrocatalytic performance of the oxygen evolution reaction in neutral media.
Behaving as structural protectors and electronic modulators, catalyst supports such as graphene derivatives are generally constructed by covalent bonds. Here, hydrogen‐bonded ultrathin nanosheets are ...reported as a new type of catalyst support. Melamine (M) and cyanuric acid (CA) molecules self‐assemble to form the graphite‐like hydrogen‐bonded co‐crystal M‐CA, which can be easily exfoliated by ultrasonic treatment to yield ultrathin nanosheets with thickness of ≈1.6 nm and high stability at pH = 0. The dynamic nanosheets form adaptive defects/pores in the synthetic process of CoP nanoparticles, giving embedded composite with high hydrogen evolution activity (overpotential of 66 mV at 10 mA cm−2) and stability. Computational calculations, X‐ray photoelectron spectroscopy, and X‐ray absorption spectroscopy unveil the electron modulation effects of the nanosheets. This pseudo‐porous catalyst support also can be applied to other metal phosphides.
A hydrogen‐bonded supramolecular network consisting of melamine and cyanuric acid is fabricated as ultrathin nanosheets with extraordinary stability at pH = 0, serving as a pseudo‐porous catalyst support to simultaneously give remarkable enhancement in the catalytic stability and activity of metal phosphides for the hydrogen evolution reaction in strong acidic conditions.
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