Photo‐controllable persistent luminescence at the single crystal level can be achieved by the integration of long‐lived room temperature phosphorescence (RTP) and photochromism within metal–organic ...frameworks (MOFs) for the first time. Moreover, the multiblock core–shell heterojunctions have been prepared utilizing the isostructural MOFs through an epitaxial growth process, in which the shell exhibits bright yellow afterglow emission that gradually disappears upon further irradiation, but the core does not show such property. Benefitting from combined persistent luminescence and photochromic behavior, a multiple encryption demo can be facilely designed based on the dynamic manipulating RTP via reversible photochromism. This work not only develops new types of dynamically photo‐controllable afterglow switch, but also provides a method to obtain MOFs‐based optical heterojunctions towards potential space/time‐resolved information encryption and anti‐counterfeiting applications.
Multiblock core–shell MOFs heterojunctions were prepared through an epitaxial growth process, in which the shell exhibits both persistent luminescence and photochromic properties. The bright yellow afterglow in MOFs shell can be detected before irradiation but almost disappears after coloration upon continuous UV irradiation.
The optical anti‐counterfeiting science and technology are currently restricted by the limited information loading capacity, and thus development of multi‐level and high‐security systems is urgently ...needed but still challenging. Herein, anti‐counterfeiting design strategies (including ASCII/5D codes and dynamic information storage) are reported by incorporation of abundant multi‐central luminescence and time‐resolved, excitation‐dependent ultralong phosphorescence. Self‐assembly of new single‐component 0D organic–inorganic metal halides (OIMHs) are facilely achieved, which exhibit divisible ultralong all‐phosphorescence, thermally activated delayed fluorescence, and single‐molecule white‐light emission, as proved by experiments and theoretical calculations. Interestingly, combing advantages of both inorganic cluster and π‐conjugation in OIMHs, the time‐dependent afterglow affords color‐variable emission in a wide wavelength range larger than 100 nm, providing extra color‐time dimensions for information encryption compared to traditional single‐color fluorescent anti‐counterfeiting. Moreover, white light‐emitting diode device is further developed to show high lighting ability for the single‐component OIMH. Therefore, this study paves an effective way to fabricate cluster‐based single‐component hybrids by equipping different emitters to confer diverse photoluminescence manners and satisfy down‐to‐earth application requirements.
This study provides a new strategy to the design of high‐performance molecular afterglow by merging clusteroluminogens and tunable π‐conjugated structures into the single‐component 0D organic–inorganic metal halides (OIMHs). The OIMHs serve as advanced single‐molecule white‐light emission and information security materials for high‐efficiency white‐light‐emitting diode dynamic information storage and high‐level anti‐counterfeiting applications.
Uncovering differences between crystalline and amorphous states in molecular solids would both promote the understanding of their structure–property relationships, as well as inform development of ...multi‐functional materials based on the same compound. Herein, for the first time, we report an approach to leverage crystalline and amorphous states of a zero‐dimensional metal‐organic complex, which exhibited negative and positive photochromism, due to the competitive chemical routes between photocycloaddition and photogenerated radicals. Furthermore, different polymorphs lead to the on/off toggling of photo‐burst movement (photosalient effect), indicating the controllable light‐mechanical conversion. Three demos were further constructed to support their application in information encryption and anti‐counterfeiting. This work provides the proof‐of‐concept of a state‐ and polymorph‐dependent photochemical route, paving an effective way for the design of new dynamically responsive systems.
An approach to leverage crystalline and amorphous states of a zero‐dimensional metal‐organic complex in order to tune negative and positive photochromism was proposed, which could be assigned to the competitive chemical routes between photocycloaddition and photogenerated radicals. Furthermore, both polymorphs exhibit mechanochromic photoemission, and lead to the on/off toggling of the light‐driven motion of bulky molecular crystals.
We investigated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) environmental contamination in 2 rooms of a quarantine hotel after 2 presymptomatic persons who stayed there were ...laboratory-confirmed as having coronavirus disease. We detected SARS-CoV-2 RNA on 8 (36%) of 22 surfaces, as well as on the pillow cover, sheet, and duvet cover.
Endometriosis is a common chronic inflammatory and estrogen-dependent disease that mostly affects people of childbearing age. The dietary inflammatory index (DII) is a novel instrument for assessing ...the overall inflammatory potential of diet. However, no studies have shown the relationship between DII and endometriosis to date. This study aimed to elucidate the relationship between DII and endometriosis. Data were acquired from the National Health and Nutrition Examination Survey (NHANES) 2001-2006. DII was calculated using an inbuilt function in the R package. Relevant patient information was obtained through a questionnaire containing their gynecological history. Based on an endometriosis questionnaire survey, those participants who answered yes were considered cases (with endometriosis), and participants who answered no were considered as controls (without endometriosis) group. Multivariate weighted logistic regression was applied to examine the correlation between DII and endometriosis. Subgroup analysis and smoothing curve between DII and endometriosis were conducted in a further investigation. Compared to the control group, patients were prone to having a higher DII (P = 0.014). Adjusted multivariate regression models showed that DII was positively correlated with the incidence of endometriosis (P < 0.05). Analysis of subgroups revealed no significant heterogeneity. In middle-aged and older women (age ≥ 35 years), the smoothing curve fitting analysis results demonstrated a non-linear relationship between DII and the prevalence of endometriosis. Therefore, using DII as an indicator of dietary-related inflammation may help to provide new insight into the role of diet in the prevention and management of endometriosis.
Exploitation of room temperature (RT) photochromism and photomagnetism to induce single-molecule magnet (SMM) behavior has potential applications toward optical switches and magnetic memories, and ...remains a tremendous challenge in the development of new bulk magnets. Herein, a series of chain complexes Ln3(H–HEDP)3(H2–HEDP)3·2H3–TPT·H4–HEDP·10H2O (QDU-1; Ln = Dy (QDU-1(Dy)), Gd (QDU-1(Gd)), and Y (QDU-1(Y)); HEDP = hydroxyethylidene diphosphonate; TPT = 2,4,6-tri(4-pyridyl)-1,3,5-triazine) were synthesized by solvothermal reactions. All the compounds exhibited reversible photochromic and photomagnetic behaviors via UV light irradiation at RT, induced by the photogenerated radicals via a photoinduced electron transfer (PET) mechanism. More importantly, the PET process induced significant variations in magnetic interactions for the Dy(III) congener. Strong ferromagnetic coupling with remarkably slow magnetic relaxation without applied dc fields was observed between DyIII ions and photogenerated O• radicals, showing SMM behavior after RT illumination. For the first time, we observed the reversible RT photochromism and photomagnetism in the lanthanide-based materials. This work realized the radicals-actuated on/off SMM behavior via RT light irradiation, providing a new strategy for constructing the light-induced SMMs.
Frogs are ideal organisms for studying sex chromosome evolution because of their diversity in sex chromosome differentiation and sex-determination systems. We review 222 anuran frogs, spanning ~220 ...Myr of divergence, with characterized sex chromosomes, and discuss their evolution, phylogenetic distribution and transitions between homomorphic and heteromorphic states, as well as between sex-determination systems. Most (~75%) anurans have homomorphic sex chromosomes, with XY systems being three times more common than ZW systems. Most remaining anurans (~25%) have heteromorphic sex chromosomes, with XY and ZW systems almost equally represented. There are Y-autosome fusions in 11 species, and no W-/Z-/X-autosome fusions are known. The phylogeny represents at least 19 transitions between sex-determination systems and at least 16 cases of independent evolution of heteromorphic sex chromosomes from homomorphy, the likely ancestral state. Five lineages mostly have heteromorphic sex chromosomes, which might have evolved due to demographic and sexual selection attributes of those lineages. Males do not recombine over most of their genome, regardless of which is the heterogametic sex. Nevertheless, telomere-restricted recombination between ZW chromosomes has evolved at least once. More comparative genomic studies are needed to understand the evolutionary trajectories of sex chromosomes among frog lineages, especially in the ZW systems.
Persistent luminescence has attracted great attention due to the unique applications in molecular imaging, photodynamic therapy, and information storage, among many others. However, tuning the ...dynamic persistent luminescence through molecular design and materials engineering remains a challenge. In this work, the first example of excitation‐dependent persistent luminescence in a reverse mode for smart optical materials through tailoring the excited‐state proton transfer process of metal cytosine halide hybrids is reported. This approach enables ultralong phosphorescence and thermally activated delayed fluorescence emission colors highly tuned by modulation of excitation wavelength, time evolution, and temperature, which realize multi‐mode dynamic color adjustment from green to blue or cyan to yellow‐green. At the single crystal level, the 2D excitation/space/time‐resolved optical waveguides with triple color conversion have been constructed on the organic‐metal halide microsheets, which represent a new strategy for multi‐dimensional information encryption and optical logic gate applications.
Reversed excitation‐dependent persistent luminescence can be obtained in metal cytosine halides by controlling the process of excited‐state proton transfer (ESIPT). The metal cytosine halides further exhibit multi‐mode (excitation/space/time) triple‐color luminescent conversion, which have promising applications in multi‐dimensional information encryption and photonic logic gates.
Activating PtSe2 monolayer for Hydrogen Evolution Reaction by defect engineering and Pd doping.
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•Pd dopant is introduced to active the basal plane for HER.•Pd doping reduces the band ...gap and enhances the catalytic ability.•Pd dopant and vacancies improve the catalytic activities comparable to that of Pt.•Band-center model is applied to better understand the difference in HER activities.
Platinum diselenide (PtSe2) has been successfully fabricated with a hope of catalytic applications. However, the active sites of pristine PtSe2 are only located at the edges while the sites in basal plane are largely inactive. To change such situation, in this study we introduce Pd dopant and vacancies to activate the basal plane for hydrogen evolution reaction (HER). Based on systematic density functional theory calculations, we find that Pd doping reduces the band gap and enhances the catalytic ability, and the divacancy sites (VSe2 and VPt2) in pristine PtSe2 monolayer and the monovacancy sites (VSe, VPd) as well as the divacancy sites (VPt2, VPdPt) in PdPtSe4 monolayer significantly improve the catalytic activities comparable to that of Pt(111). A band-center model is applied to better understand the difference in HER activities, where the chemical bond energies of H (ΔG1) show an approximately linear relationship with the energy of d/p level of Pt/Se. The strategy proposed here would be applicable to other two-dimensional materials.
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