An ideal anti-counterfeiting technique has to be inexpensive, mass-producible, nondestructive, unclonable and convenient for authentication. Although many anti-counterfeiting technologies have been ...developed, very few of them fulfill all the above requirements. Here we report a non-destructive, inkjet-printable, artificial intelligence (AI)-decodable and unclonable security label. The stochastic pinning points at the three-phase contact line of the ink droplets is crucial for the successful inkjet printing of the unclonable security labels. Upon the solvent evaporation, the three-phase contact lines are pinned around the pinning points, where the quantum dots in the ink droplets deposited on, forming physically unclonable flower-like patterns. By utilizing the RGB emission quantum dots, full-color fluorescence security labels can be produced. A convenient and reliable AI-based authentication strategy is developed, allowing for the fast authentication of the covert, unclonable flower-like dot patterns with different sharpness, brightness, rotations, amplifications and the mixture of these parameters.
Nearly monodisperse zinc-blende CdSe/CdS core/shell nanocrystals were synthesized by epitaxial growth of 1–6 monolayers of CdS shell onto presynthesized zinc-blende CdSe core nanocrystals in one pot. ...To retain the zinc-blende structure, the reaction temperature was lowered to the 100–140 °C range by using cadmium diethyldithiocarbamate as a single-source precursor and primary amine as activation reagents for the precursor. Although the wurtzite counterparts grown under the same conditions showed optical properties similar to those reported in the literature, zinc-blende CdSe/CdS core/shell nanocrystals demonstrated surprisingly different optical properties, with ensemble single-exponential photoluminescence decay, significant decrease of photoluminescence peak width by the shell growth, and comparatively high photoluminescence quantum yields. The lifetime for the single-exponential ensemble photoluminescence decay of zinc-blende CdSe/CdS core/shell nanocrystals with 3–4 monolayers of CdS shell was reproducibly found to be approximately 16.5 ± 1.0 ns.
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A one-pot/three-step synthetic scheme was developed for phase-pure epitaxy of CdS shells on zinc-blende CdSe nanocrystals to yield shells with up to sixteen monolayers. The key parameters for the ...epitaxy were identified, including the core nanocrystal concentration, solvent type/composition, quality of the core nanocrystals, epitaxial growth temperature, type/concentration of ligands, and composition of the precursors. Most of these key parameters were not influential when the synthetic goal was thin-shell CdSe/CdS core/shell nanocrystals. The finalized synthetic scheme was reproducible at an almost quantitative level in terms of the crystal structure, shell thickness, and optical properties.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Ordered mesoporous alumina (OMA) has been widely used as the adsorbents and catalyst supports due to their unique properties including highly uniform channels and large specific surface area. ...However, the thermal stability is not ideal enough. In this work, P-doped γ-Al2O3, which still maintained ordered mesoporous structure even when calcined at 1000 °C, was successfully synthesized via a sol-gel procedure with acetic acid as interfacial protector. The influence of the addition of phosphorus on the physicochemical properties of OMA and the catalytic behavior of its supported Pd catalyst was investigated by combining several characterization methods with catalytic activity test. The results showed that the introduction of phosphorus resulted in enhanced thermal stability, improved surface acid-base performance and increased reducibility of the Pd-alumina catalysts, all of which contributed to the excellent catalytic performance in conversion of hydrocarbon (HC), CO, and NOx. The obtained P-doped OMA is anticipated to be explored in other high temperature reactions due to its unique thermal stability and acid-base performance.
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•Phosphorus-doped ordered mesoporous alumina with high surface area was obtained.•Doping of P improves thermal stability and surface acid-base property of γ-Al2O3.•Pd/P-OMA-10 represents high catalytic performances for CO, NOx and HC elimination.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Perovskite quantum dots (PeQDs) have emerged as a new kind of nanomaterial in various applications, especially light-emitting diodes (LEDs). However, the synthesis of PeQDs is relatively complicated ...and the electron transport layer (ETL) is usually fabricated in a vacuum because of the dissolution of PeQDs films in organic solvents, which will increase the difficulty and cost in mass production. Here, a simple one-step “ultrasonic bath” treatment to synthesis PeQDs is adopted and applied into the PeQDs-LEDs. Meanwhile, an all-solution process is developed to fabricate PeQDs-LEDs based on the solvent engineering strategy. By using methyl acetate (MeOAc) as the solvent of ETL, the all-solution-processed PeQDs-LEDs exhibit bright luminance with the maximum current efficiency of 3.26 cd/A. This work is simple and easy to be scaled up, which will pave a new way to the low-cost all-solution processable PeQDs-LEDs.
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To compare the recurrence rate and prognosis between minimally invasive surgical (MIS) approach and open surgical approach of endometrial carcinoma (EC) patients with different prognostic risk ...groups.
A retrospective analysis of all cases undergoing EC surgery between January 2011 and March 2018 was performed. The patients were grouped according to the management guidelines of EC patients jointly formulated by the ESGO/ESTRO/ESP 2020. Different surgical approaches were compared with regard to tumor characteristics, recurrence rate, disease-free survival (DFS), and overall survival (OS).
A total of 665 patients met the inclusion criteria of which 196 patients underwent MIS (29.5%), and 469 patients underwent open surgery (70.5%). In the MIS group, there was a significant higher rate of recurrence (17.3% vs 6.6%, P = 0.000) compared to the open surgery group. The recurrence rate of MIS was 7.7% (P = 0.000) in the medium-high risk group and 8.2% (P = 0.014) in the high-risk group. Multivariate logistic regression analysis showed that the independent factors influencing recurrence included prognostic risk grouping, surgical approach and lymph vascular space invasion (LVSI) positivity (P < 0.05). K-M survival analysis revealed that in the intermediate and high-risk group of EC, MIS patients had a significantly lower DFS than those undergoing open surgery (P < 0.05), but no significant difference was found in OS.
For patients with EC at moderate and high prognostic risk, MIS is associated with poorer DFS compared to open surgery, but OS was similar across prognostic risk groups. The application of MIS in patients with moderate and high-risk EC needs further research and analysis.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Using CdSe/CdS core/shell nanocrystals with 1-10 monolayers of CdS shell as the model system, we studied effects of thiol ligands on optical properties of the nanocrystals. The core/shell ...nanocrystals with original ligands possessed near unity photoluminescence （PL） quantum yield and single-exponential PL decay dynamics. The effects of thiol ligands on optical properties were found to depend on the shell thickness, environment （with/without oxygen）, and excitation power （single- or multi-exciton）. Systematic and quantitative results reported in this work should provide necessary information for fundamental understanding and technical applications of quantum dots （QDs） coated with thiol ligands.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Introducing glycans represents an efficient chemical approach to improve the pharmacological properties of therapeutic biomolecules. Herein, we report an efficient synthesis of glycoconjugates ...through chlorooxime–thiol conjugation. The reactive glycosyl chlorooximes, derived from pyranoses or furanoses, readily couple to a wide range of thiol-containing substrates, including peptides, sugars, and thiophenols. This method features mild reaction conditions and fast kinetics. Capability for aqueous media and gram-scale synthesis demonstrates the potential of this method in the bioconjugation of saccharides with biologically active molecules.
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Recent theoretical studies revealed that two-dimensional (2D) antimonene has attractive characteristics, such as superior photothermal conductivity, absorption over a wide range, high mobility, and ...good spintronic properties. Herein, we report a reliable liquid phase exfoliation (LPE) route for the preparation of high-quality high-stability atomically thin (AT) antimonene via high ultrasonic power. The AT antimonene delivers a high specific capacity of up to 860 mA·h·g
–1
, with high rate capability and good cycling stability as an anode of a sodium ion battery (SIB). The good conductivity and 2D structure endow AT antimonene with more active sites for sodium storage, a facilitated pathway for electron transfer and mass transport, and the capability to reduce the volume expansion during the discharge–charge process.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Understanding photoluminescence (PL) intermittency of single quantum dots (QDs) (intensity blinking by randomly switching between distinguishable brightness states under continuous excitation) has ...been a long-standing fundamental challenge and potential roadblock for their applications. Here we introduce a new analysis method for single-molecule spectroscopy that treats the blinking as photochemical/chemical processes (switching between neutral/bright and charged/dim states). It uncovers the channels for charging (bright to dim) and discharging (dim to bright) involved in PL blinking of single CdSe/CdS core/shell QDs. Both charging and discharging of the single CdSe/CdS core/shell QD possess a photochemical channel (∼10–5 to 10–6 events/photon) that linearly depends on excitation in both single- and multi-exciton regime. These two linear channels coupled to a spontaneous discharging channel (∼2 events/s) to dictate the QDs from nonblinking to gradually blinking under increasing excitation. For high-quality CdSe/CdS core/shell QDs, Auger ionization of multiexciton for both charging and discharging is negligible.
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