Rational exploration of efficient, inexpensive, and robust electrocatalysts is critical for the efficient water splitting. Conjugated conductive metal–organic frameworks (cMOFs) with multicomponent ...layered double hydroxides (LDHs) to construct bifunctional heterostructure catalysts are considered as an efficient but complicated strategy. Here, the fabrication of a cMOF/LDH hetero‐nanotree array catalyst (CoNiRu‐NT) coupled with monodispersed ruthenium (Ru) sites via a controllable grafted‐growth strategy is reported. Rich‐amino hexaiminotriphenylene linkers coordinate with the LDH nanotrunk to form cMOF nanobranches, providing numerous anchoring sites to precisely confine and stabilize RuN4 sites. Moreover, monodispersed and reduced Ru moieties facilitate H2O adsorption and dissociation, and the heterointerface between the cMOF and the LDH further modifies the chemical and electronic structures. Optimized CoNiRu‐NT displays a significant increase in electrochemical water‐splitting properties in alkaline media, affording low overpotentials of 22 mV at 10 mA cm−2 and 255 mV at 20 mA cm−2 for the hydrogen evolution reaction and oxygen evolution reaction, respectively. In an actual electrochemical system, CoNiRu‐NT drives an overall water splitting at a low cell voltage of 1.47 V to reach 10 mA cm−2. This performance is comparable to that of pure noble‐metal‐based materials and superior to most reported MOF‐based catalysts.
A conductive metal–organic framework (cMOF)/layered double hydroxide (LDH) hetero‐nanotree structure coupled with monodisperse Ru sites is constructed via a controllable grafted‐growth strategy. Based on a competitive coordination process, RuN sites are precisely anchored by rich‐amino organic linkers. The chemical and electronic structure of the hetero‐nanotree catalysts are well modified and lead to a superior overall water‐splitting performance in alkaline media.
This study aimed to investigate the safety and feasibility of a novel stent-assisted ileal bypass for rectal cancer patients who received sphincter-preserving surgery.
Patients who were diagnosed ...with rectal cancer and received sphincter-preserving surgery plus a novel stent-assisted ileal bypass were respectively included from January 2022 to January 2023. Biofragmentable ileal stent with diaphragm sheet in the cavity was placed in the terminal ileum using absorbable sutures after anastomosis. At the proximal end of the stent, an intestinal diversion tube was placed in the prefabricated purse-string, through which faeces were drained. The stent completely disintegrated in the body after 3-4 weeks, which protected the anastomosis after surgery and avoided protective stoma. Clinical characteristics and surgical outcomes were collected.
Eleven patients who successfully received surgery were included. There were seven (63.6%) males and four (36.4%) females. The tumour size was 3.2 ± 1.7 cm and the lower verge of tumour to anal verge was 6.8 ± 1.3 cm. As for surgical outcomes, operation time was 216.4 ± 54.1 min, blood loss was 43.6 ± 64.6 mL, time to first flatus via intestinal diversion tube was 3.2 ± 1.1 days, time to discharge stent was 22.8 ± 3.0 days, and postoperative hospital stay was 21.0 ± 5.4 days. Two patients suffered from postoperative complications including pneumonia and incision infection.
This novel stent-assisted ileal bypass is safe and feasible, it provides a new choice for rectal cancer patients to avoid protective stoma and secondary surgery.
Rationally tuning the emission position and narrowing the full width at half‐maximum (FWHM) of an emitter is of great importance for many applications. By synergistically improving rigidity, ...strengthening the resonant strength, inhibiting molecular bending and rocking, and destabilizing the HOMO energy level, a deep‐blue emitter (CZ2CO) with a peak wavelength of 440 nm and an ultranarrow spectral FWHM of 16 nm (0.10 eV) was developed via intramolecular cyclization in a carbonyl/N resonant core (QAO). The dominant υ0‐0 transition character of CZ2CO gives a Commission Internationale de I’Éclairage coordinates (CIE) of (0.144, 0.042), nicely complying with the BT.2020 standard. Moreover, a hyper‐fluorescent device based on CZ2CO shows a high maximum external quantum efficiency (EQEmax) of 25.6 % and maintains an EQE of 22.4 % at a practical brightness of 1000 cd m−2.
A multi‐resonance emitter using intramolecular cyclization endows BT.2020‐compliant deep blue emission with an ultranarrow full width at half maximum (FWHM) of 16 nm and CIE coordinates of (0.153, 0.042) in toluene, thus achieving a high external quantum efficiency of 25.6 % in a hyper‐fluorescent organic light‐emitting diode.
A spin-flip from a triplet to a singlet excited state, that is, reverse intersystem crossing (RISC), is an attractive route for improving light emission in organic light-emitting diodes, as shown by ...devices using thermally activated delayed fluorescence (TADF). However, device stability and efficiency roll-off remain challenging issues that originate from a slow RISC rate (kRISC). Here, we report a TADF molecule with multiple donor units that form charge-resonance-type hybrid triplet states leading to a small singlet–triplet energy splitting, large spin–orbit couplings, and a dense manifold of triplet states energetically close to the singlets. The kRISC in our TADF molecule is as fast as 1.5 × 107 s−1, a value some two orders of magnitude higher than typical TADF emitters. Organic light-emitting diodes based on this molecule exhibit good stability (estimated T90 about 600 h for 1,000 cd m−2), high maximum external quantum efficiency (>29.3%) and low efficiency roll-off (<2.3% at 1,000 cd m−2).An organic molecule, 5Cz-TRZ, with multiple donor units supports fast reverse intersystem crossing, allowing fabrication of high-performance organic light-emitting diodes.
Organic light‐emitting diodes (OLEDs) are the most successful product of organic electronics in the market and continually receive attention from scientific and industrial communities. Imidazoles ...have been extensively investigated for OLED applications, and demonstrated their versatility in molecular design for different functions. This review presents a summary of recent studies on imidazole (including imidazole derived moieties) derivatives, with special focus on discussing various molecular design tactics, for applications as electron‐transporting materials, emitters, and host materials in OLEDs. At last, perspectives and challenges regarding to imidazole semiconductors for electroluminescence applications are also discussed.
Imidazole semiconductors as components with various functions in organic light‐emitting diodes (OLEDs) are reviewed. The development of imidazole‐based materials as electron transporting materials, emitters, and host materials for phosphorescent OLEDs is discussed, with special attention on their molecular design tactics and relationships among structures, physical properties, and performances.
Precise design of low‐cost, efficient and definite electrocatalysts is the key to sustainable renewable energy. Herein, this work develops a targeted‐anchored and subsequent spontaneous‐redox ...strategy to synthesize nickel‐iron layered double hydroxide (LDH) nanosheets anchored with monodispersed platinum (Pt) sites (Pt@LDH). Intermediate metal‐organic frameworks (MOF)/LDH heterostructure not only provides numerous confine points to guarantee the stability of Pt sites, but also excites the spontaneous reduction for PtII. Electronic structure, charge transfer ability and reaction kinetics of Pt@LDH can be effectively facilitated by the monodispersed Pt moieties. As a result, the optimized Pt@LDH that with the 5% ultra‐low content Pt exhibits the significant increment in electrochemical water splitting performance in alkaline media, which only afford low overpotentials of 58 mV at 10 mA cm−2 for hydrogen evolution reaction (HER) and 239 mV at 10 mA cm−2 for oxygen evolution reaction (OER), respectively. In a real device, Pt@LDH can drive an overall water‐splitting at low cell voltage of 1.49 V at 10 mA cm−2, which can be superior to most reported similar LDH‐based catalysts. Moreover, the versatility of the method is extended to other MOF precursors and noble metals for the design of ultrathin LDH supported monodispersed noble metal electrocatalysts promoting research interest in material design.
A targeted‐anchored and subsequent spontaneous‐redox strategy is developed to synthesize nickel‐iron layered double hydroxide (LDH) nanosheets anchored with monodispersed platinum (Pt) sites (Pt@LDH). As‐prepared Pt@LDH‐4h can drive an overall water‐splitting at low cell voltage of 1.49 V at 10 mA cm−2, which can be superior to most reported similar LDH‐based catalysts.
In the past, long-distance free-space quantum communication experiments could only be implemented at night. During the daytime, the bright background sunlight prohibits quantum communication in ...transmission under conditions of high channel loss over long distances. Here, by choosing a working wavelength of 1,550 nm and developing free-space single-mode fibre-coupling technology and ultralow-noise upconversion single-photon detectors, we have overcome the noise due to sunlight and demonstrate free-space quantum key distribution over 53 km during the day. The total channel loss is ∼48 dB, which is greater than the 40 dB channel loss between the satellite and ground and between low-Earth-orbit satellites. Our system thus demonstrates the feasibility of satellite-based quantum communication in daylight. Moreover, given that our working wavelength is located in the optical telecom band, our system is naturally compatible with ground fibre networks and thus represents an essential step towards a satellite-constellation-based global quantum network.
Abstract
Eicosapentaenoic acid (EPA), an omega-3 fatty acid, has been widely used to prevent cardiovascular disease (CVD) and treat brain diseases alone or in combination with docosahexaenoic acid ...(DHA). However, the impact of EPA and DHA supplementation on normal cognitive function and the molecular targets of EPA and DHA are still unknown. We show that acute administration of EPA impairs learning and memory and hippocampal LTP in adult and prepubescent mice. Similar deficits are duplicated by endogenously elevating EPA in the hippocampus in the transgenic fat-1 mouse. Furthermore, the damaging effects of EPA are mediated through enhancing GABAergic transmission via the 5-HT
6
R. Interestingly, DHA can prevent EPA-induced impairments at a ratio of EPA to DHA similar to that in marine fish oil via the 5-HT
2C
R. We conclude that EPA exhibits an unexpected detrimental impact on cognitive functions, suggesting that caution must be exercised in omega-3 fatty acid supplementation and the combination of EPA and DHA at a natural ratio is critical for learning and memory and synaptic plasticity.
The employment of bentonite modified loess (BML) is a common method of constructing the anti-seepage lining of landfills in the loess region of China, and its long-term secure performance is ...threatened by wetting-drying (W-D) cycles. Taking the remolded loess (RL) and BML with 15% in mass of bentonite as research objects, the W-D cycles test, scanning electron microscope test and direct shear test were carried out to analyze the effects of W-D cycles on the microstructure and shear strength of samples. The regression equations between strength and micro-pore structure parameters were established by the multivariate linear stepwise regression method. The damage mechanism of BML after W-D cycles was studied by establishing damage degree models based on pore area ratio and cohesion. Results indicate that the water absorption and expansion of bentonite effectively block the intergranular pores, resulting in more medium and small pores and more pronounced surface contact of particles. After W-D cycles, the particle arrangement of samples before and after bentonite modification tends to be loose. Both the pore area ratio and fractal dimension increase and tend to stabilize after five cycles. The BML exhibits lower pore area ratio and greater fractal dimension while its cohesion and internal friction angle show more significant decrease after W-D cycles than those of RL. The damage variables based on pore area ratio and cohesion well describe the W-D induced damage of loess before and after modification from macro- and micro-scale perspectives. The damage degree of samples increases with W-D cycles, but the increment decreases.
Our study aims to investigate whether preoperative red blood cell distribution width (RDW) has a prognostic value for patients after gastric cancer (GC) surgery. We searched articles in 3 databases ...including PubMed, Embase, and the Cochrane Library on May 16th, 2022. The prognostic indicators included overall survival (OS) and disease-free survival (DFS). RevMan 5.3 (The Cochrane Collaboration, London, United Kingdom) and Stata V16.0 were used for statistical analysis. The Risk Of Bias In Non-randomized Studies—of Interventions tool was used to assess risk of bias of the included studies. Ten articles involving 2740 patients were included. RDW was a prognostic factor for OS (hazard ratio = 1.81, 95% confidence interval CI = 1.38–2.37, P < .01) and DFS (hazard ratio = 1.99, I 2 = 26%, 95% CI = 1.53–2.58, P < .01) for GC patients. Meanwhile, there were some differences between the high RDW group and the low RDW group. We found more patients older than 60 years old (OR = 2.58, 95% CI = 1.08–6.13, P = .03), larger tumor diameter (OR = 1.95, 95% CI = 1.33–2.85, P < .01) and later T stage (OR = 1.91, 95% CI = 1.07–3.42, P = .03) in the high RDW group than the low RDW group. No statistic difference was found in gender, N stage, tumor node metastasis stage, vascular invasion, differentiation, and adjuvant therapy between the 2 groups ( P > .05). RDW was an independent prognostic factor for both OS and DFS of GC patients. High RDW level were strongly associated with poor survival.
PDF
