Nowadays, phosphor converted white light-emitting diodes (pc-WLEDs) have been widely used in solid-state lighting and display areas due to their superior lifetime, efficiency, and reliability as well ...as significant reduction in power consumption. Phosphors are indispensable components of pc-WLED devices, and their luminescence properties determine the quality of WLED lighting and displays. In order to further achieve high luminous efficacy, chromatic stability, and color-rending properties in pc-WLEDs, much effort has been focused on improving current pc-WLED phosphors and developing novel pc-WLED phosphors recently. This review article concerns commonly used rare earth ion (Eu
2+
and Ce
3+
) activated inorganic phosphors, highlighting the important effect of spectral tuning
via
local structural variations on improving the luminescence performance of phosphors. The main spectral tuning strategies are discussed in detail and summarized, including (1) doping level control; (2) cationic substitution; (3) anionic substitution; (4) cationic-anionic substitution; (5) the crystal-site engineering approach; (6) mixing of nanophases.
This review is devoted to several approaches to realize spectral tuning for improving the luminescence performance of Ce
3+
and Eu
2+
-activated pc-WLED phosphors.
Achieving white‐light emission, especially white circularly polarized luminescence (CPL) from a single‐phase material is challenging. Herein, a pair of chiral CuI coordination polymers (1‐M and 1‐P) ...have been prepared by the asymmetrical assembly of achiral ligands and Cu2I2 clusters. The compounds display dual emission bands and can be used as single‐phase white‐light phosphors, achieving a “warm”‐white‐light‐emitting diode with an ultra‐high color rendering index (CRI) of 93.4 and an appropriate correlated color temperature (CCT) of 3632 K. Meanwhile, corresponding CPL signals with maximum dissymmetry factor |glum|=8×10−3 have been observed. Hence, intrinsic white‐light emission and CPL have been realized simultaneously in coordination polymers for the first time. This work gains insight into the nature of chiral assembly from achiral units and offers a prospect for the development of single‐phase white‐CPL materials.
A pair of chiral CuI coordination polymers (1‐P/M) were produced from achiral precursors by crystallization‐driven symmetry‐breaking assembly. The enantiomers feature unique helical layered structures and tunable dual‐emission photoluminescence, achieving intrinsic “warm”‐white emitting with an ultra‐high color rendering index (93.4) and circularly polarized luminescence with a remarkable dissymmetry factor (8×10−3) simultaneously.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
To conquer the bottleneck of sluggish kinetics in cathodic oxygen reduction reaction (ORR) of metal‐air batteries, catalysts with dual‐active centers have stood out. Here, a “pre‐division metal ...clusters” strategy is firstly conceived to fabricate a N,S‐dual doped honeycomb‐like carbon matrix inlaid with CoN4 sites and wrapped Co2P nanoclusters as dual‐active centers (Co2P/CoN4@NSC‐500). A crystalline {CoII2} coordination cluster divided by periphery second organic layers is well‐designed to realize delocalized dispersion before calcination. The optimal Co2P/CoN4@NSC‐500 executes excellent 4e− ORR activity surpassing the benchmark Pt/C. Theoretical calculation results reveal that the CoN4 sites and Co2P nanoclusters can synergistically quicken the formation of *OOH on Co sites. The rechargeable Zn‐air battery (ZAB) assembled by Co2P/CoN4@NSC‐500 delivers ultralong cycling stability over 1742 hours (3484 cycles) under 5 mA cm−2 and can light up a 2.4 V LED bulb for ≈264 hours, evidencing the promising practical application potentials in portable devices.
A “pre‐division metal clusters” strategy is first conceived to fabricate dual‐active center catalysts (Co2P/CoN4@NSC‐500) with dispersed CoN4 and Co2P sites. The optimal catalyst executes superior ORR activity and was applied in ultralong Zn‐air batteries surpassing the benchmark 20 % Pt/C. Theoretical calculations demonstrate that the dual‐active sites synergistically quicken the formation of the *OOH intermediate, greatly boosting the performance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The removal of C2H2 and C2H6 from C2H4 streams is of great significance for feedstock purification to produce polyethylene and other commodity chemicals but the simultaneous adsorption of C2H6 and ...C2H2 over C2H4 from a ternary mixture has never been realized. Herein, a robust metal–organic framework, TJT‐100, was designed and synthesized, which demonstrates remarkably selective adsorption of C2H2 and C2H6 over C2H4. Breakthrough experiments show that TJT‐100 can be used as an adsorbent for high‐performance purification of C2H4 from a ternary mixture of C2H2/C2H4/C2H6 (0.5:99:0.5) to afford a C2H4 purity greater than 99.997 %, beyond that required for ethylene polymerization. Computational studies reveal that the uncoordinated carboxylate oxygen atoms and coordinated water molecules pointing towards the pore can trap C2H2 and C2H6 through the formation of multiple C−H⋅⋅⋅O electrostatic interactions, while the corresponding C2H4–framework interaction is unfavorable.
A robust porous metal–organic framework was synthesized and utilized for the highly selective separation of C2H4 from a ternary mixture of C2 hydrocarbons. After a single operation, the C2H4 purity of the outlet was greater than 99.997 %.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A disturbance prediction-based adaptive event-triggered model predictive control scheme is proposed for nonlinear systems in the presence of slowly varying disturbance. The optimal control problem in ...the model predictive control scheme is formulated by taking advantage of a proposed central path-based disturbance prediction approach, and the event-triggered mechanism is designed to be adaptive to the triggering interval. As a result, the proposed scheme improves the state prediction precision and, hence, reduces greatly the triggering frequency. Furthermore, for input-affine nonlinear systems, the disturbance separation and compensation techniques are developed to further enlarge the triggering interval. The theoretical analysis of the algorithm feasibility and closed-loop stability, as well as numerical evaluations of the effectiveness of the proposed schemes, is also given.
Long noncoding RNAs (lncRNAs) are emerging as an integral part of the regulatory information encoded in the genome. lncRNAs possess the unique capability to interact with nucleic acids and proteins, ...and exert discrete effects on numerous biological processes. Recent studies have delineated multiple lncRNA pathways that control metabolic tissue development and function. The expansion of the regulatory code that links nutrient and hormonal signals to tissue metabolism gives new insights into the genetic and pathogenic mechanisms underlying metabolic disease. This review discusses lncRNA biology with a focus on their role in the development, signaling, and function of key metabolic tissues.
lncRNAs exhibit tissue-specific and highly regulated expression patterns, and are frequently dysregulated in disease states.
lncRNAs regulate diverse biological processes through the formation of lncRNA–protein and lncRNA–miRNA complexes to control gene expression and function.
lncRNAs regulate metabolic tissue development and function, including adipogenesis, hepatic lipid metabolism, islet function, and energy balance.
lncRNAs are important regulators of skeletal and cardiac muscle development, and of the immune response.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Hepatic lipogenesis is aberrantly induced in nonalcoholic fatty liver disease (NAFLD) via activation of the LXR-SREBP1c pathway. To date, a number of protein factors impinging on the transcriptional ...activity of LXR and SREBP1c have been elucidated. However, whether this regulatory axis interfaces with long noncoding RNAs (lncRNAs) remains largely unexplored. Here we show that hepatic expression of the lncRNA Blnc1 is strongly elevated in obesity and NAFLD in mice. Blnc1 is required for the induction of SREBP1c and hepatic lipogenic genes in response to LXR activation. Liver-specific inactivation of Blnc1 abrogates high-fat diet-induced hepatic steatosis and insulin resistance and protects mice from diet-induced nonalcoholic steatohepatitis. Proteomic analysis of the Blnc1 ribonucleoprotein complex identified EDF1 as a component of the LXR transcriptional complex that acts in concert with Blnc1 to activate the lipogenic gene program. These findings illustrate a lncRNA transcriptional checkpoint that licenses excess hepatic lipogenesis to exacerbate insulin resistance and NAFLD.
A scalable enantioselective nickel-catalyzed electrochemical reductive homocoupling of aryl bromides has been developed, affording enantioenriched axially chiral biaryls in good yield under mild ...conditions using electricity as a reductant in an undivided cell. Common metal reductants such as Mn or Zn powder resulted in significantly lower yields in the absence of electric current under otherwise identical conditions, underscoring the enhanced reactivity provided by the combination of transition metal catalysis and electrochemistry.
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IJS, KILJ, NUK, PNG, UL, UM
Strong adsorption and catalysis for lithium polysulfides (LiPSs) are critical toward the electrochemical stability of Li‐S batteries. Herein, a hollow sandwiched nanoparticle is put forward to ...enhance the adsorption‐catalysis‐conversion dynamic of sulfur species. The outer ultrathin Ni(OH)2 nanosheets not only confine LiPSs via both physical encapsulation and chemical adsorption, but also promote redox kinetics and accelerate the conversion of sulfur species, which is revealed by experiments and theoretical calculations. Meanwhile, the inner hollow polyaniline soft core provides a strong chemical bonding to LiPSs after vulcanization, which can chemically adsorpt LiPSs, and synergistically confine the shuttle effect. Moreover, the Ni(OH)2 nanosheets with a large specific area can enhance the wettability of electrolyte, and the flexible hollow sandwiched structure can accommodate the volume expansion, promoting sulfur utilization and structural stability. The obtained cathode exhibits excellent electrochemical performance with an initial discharge capacity of 1173 mAh g–1 and a small capacity decay of 0.08% per cycle even after 500 cycles at 0.2 C, among the best results of Ni(OH)2‐based materials for Li–S batteries. It is believed that the combination of adsorption‐catalysis‐conversion will shed a light on the development of cathode materials for stable Li–S batteries.
A sandwiched Ni(OH)2@S@P cathode is designed for stable Li–S batteries. The outer ultrathin Ni(OH)2 nanosheets enhance conversion kinetics of sulfur species, and endows a robust physical encapsulation and chemical adsorption for lithium polysulfides (LiPSs). The inner hollow polyaniline core provides a strong chemical bonding to LiPSs after vulcanization, synergistically inhibiting the LiPSs diffusion. The hollow/flexible structure accommodates volume expansion and improves sulfur utilization.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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