Search

In this study, peptide‐based self‐assembled nanosheets with a thickness of approximately 1 nm were prepared using a hierarchical covalent physical fabrication strategy. The covalent alternating polymerization of helical peptide E3 with an azobenzene (AZO) structure yielded copolymers CoP(E3‐AZO), which physically self‐assembled into ultrathin nanosheets in an unanticipated two‐dimensional horizontal monolayer arrangement. This special monolayer arrangement enabled the thickness of the nanosheets to be equal to the cross‐sectional diameter of a single linear copolymer, which is a rare phenomenon. Molecular dynamics simulations suggested that the synergistic effect of multiple molecular interactions drives the self‐assembly of CoP(E3‐AZO) into nanosheets and that various methods, including phototreatment, pH adjustment, the addition of additives, and introduction of cosolvents, can alter the molecular interactions and modulate the self‐assembly of CoP(E3‐AZO), yielding diverse nanostructures. Remarkably, the ultrathin nanosheets selectively inhibited cancer cells at certain concentrations. [ABSTRACT FROM AUTHOR]

High‐quality hosts are indispensable for simultaneously realizing stable, high efficiency, and low roll‐off blue solution‐processed organic light‐emitting diodes (OLEDs). Herein, three solution processable bipolar hosts with successively reduced triplet energies approaching the T1 state of thermally activated delayed fluorescence (TADF) emitter are developed and evaluated for high‐performance blue OLED devices. The smaller T1 energy gap between host and guest allows the quenching of long‐lived triplet excitons to reduce exciton concentration inside the device, and thus suppresses singlet‐triplet and triplet‐triplet annihilations. Triplet‐energy‐mediated hosts with high enough T1 and better charge balance in device facilitate high exciton utilization efficiency and uniform triplet exciton distribution among host and TADF guest. Benefited from these synergetic factors, a high maximum external quantum efficiency (EQEmax) of 20.8%, long operational lifetime (T50 of 398.3 h @ 500 cd m−2), and negligible efficiency roll‐off (EQE of 20.1% @ 1000 cd m−2) are achieved for bluish‐green TADF OLEDs. Additionally introducing a narrowband emission multiple‐resonance TADF material as terminal emitter to accelerate exciton dynamic and improve exciton utilization, a higher EQEmax of 23.1%, suppressed roll‐off and extended lifetime of 456.3 h are achieved for the sky‐blue sensitized OLEDs at the same brightness. [ABSTRACT FROM AUTHOR]

Jigucao capsules (JGCC) have the effects of soothing the liver and gallbladder and clearing heat and detoxification. It is a good medicine for treating acute and chronic hepatitis cholecystitis with damp heat of the liver and gallbladder. However, the existing quality standard of JGCC does not have content determination items, which is not conducive to quality control. In this study, serum pharmacochemistry technology and UNIFI data processing software were used to identify the blood prototype components and metabolites under the condition of the obvious drug effects of JGCC, and the referenced literature reports and the results from in vitro analysis of JGCC in the early stage revealed a total of 43 prototype blood components and 33 metabolites in JGCC. Quality markers (Q-markers) were discovered, such as abrine, trigonelline, hypaphorine and isoschaftoside. In addition, ultra-high-performance liquid chromatography–triple quadrupole mass spectrometry (UPLC-QQQ-MS) was used to determine the active ingredients in JGCC. The components of quantitative analysis have good correlation in the linear range with R2 ≥ 0.9993. The recovery rate is 93.15%~108.92% and the relative standard deviation (RSD) is less than 9.48%. The established UPLC-MS/MS quantitative analysis method has high sensitivity and accuracy, and can be used for the quality evaluation of JGCC. [ABSTRACT FROM AUTHOR]

• Construction of ecological compensation standard accounting model based on spillover theory. • The number of areas paying eco-compensation and the number of areas receiving eco-compensation are about the same. • Ecologically important areas should receive EC, and economically developed areas should pay EC. • Ecosystem service flows occur mainly in areas where the value of ecosystem services is high. A program of ecological compensation (EC) is an effective means to solve the potential unfairness caused by the difference in environmental quality between the upper, middle, and lower reaches of river basins, alleviate the conflict of economic interests between regions. By constructing an EC accounting model, this study defines the carbon emissions of construction land as the consumption of ecological services to avoid the problem of lower EC in the upper reaches than the middle and lower reaches when only the ecosystem service value (ESV) is used as the compensation basis. We calculate the cumulative EC standards in the basin from 2000 to 2018 at the county, major functional oriented zone, and basin section scales, divide the subjects unto those provide EC and the subjects receiving EC, and finally introduce the comparative ecological radiation force to simulate the direction and scale of the ecosystem service flow (ESF) of the subjects receiving EC. The findings of this study are as follows: (1) The ESV of the Minjiang River Basin shows a downward trend in time and a spatial distribution pattern of high in the north and southwest parts and low in the middle and southeast parts. (2) Carbon emissions from construction land in all counties (cities and districts) in the Minjiang River Basin show an upward trend in time and a spatial distribution pattern of high in the middle part and low in the north and south parts. (3) The cumulative EC standard in the Minjiang River Basin from 2000 to 2018 is 279.401 billion CNY, which indicates ESV spillover. On the county scale, 22 subjects receive EC and 23 subjects providing EC. The subjects receiving EC are generally located in the southwestern parts of the upper and lower reaches, and the subjects providing EC are concentrated in the national key development zone in the middle reaches. (4) The ESF goes from north to south in the upper reaches, towards the north and south sides in the middle reaches, and towards the east and north in the lower reaches. Our findings provide an important reference for EC practices in the Minjiang River Basin. [ABSTRACT FROM AUTHOR]

Low dimensional lead‐free metal halides have become the spotlight of the research on developing multifunctional optoelectronic materials as their properties show a wide range of tunability. However, most reported low dimensional metal halides only function in the ultra‐violet to visible range due to their large bandgap. Moreover, the organic cation based low dimensional metal halides show limited thermal stability; on the other hand, their inorganic cation based counterparts suffer from limited solution processability. A hybrid cation approach is proposed, where a zero dimensional (0D) metal halide ((DFPD)2CsBiI6) is developed by using mixed organic–inorganic cations: 4, 4‐difluoropiperidine (DFPD) and cesium (Cs+). This ensures both thermal stability and solution processability. Furthermore, [BiI6]3− octahedra are serving as active light absorption units, which ensures the bandgap to be located at the visible region. Its photoluminescence (PL) is further shifted to the near infrared (NIR) region by doping (DFPD)2CsBiI6 with antimony (Sb3+). The developed materials show multifunctional properties: thermochromic behavior, light detection, and NIR light emitting. This study expands the scope of developing multifunctional 0D metal halides. [ABSTRACT FROM AUTHOR]

China shares more than 20 transboundary aquifers with its coaquifer states, but they have not exploited their transboundary groundwater resources, and these resources have not been governed by any international agreements. Given the close interaction between surface water and groundwater, and the growing demands for transboundary groundwater in China and its coaquifer states, there is increasing necessity for these countries to undertake international cooperation on this issue. This article overviews China's transboundary aquifers, reviews the duty to cooperate on China's transboundary groundwater as well as the emerging transboundary aquifer law. It concludes by providing some proposals on international cooperation in this context, based on the two theories of international water law-limited territorial sovereignty and common interests, taking into account the practicability of China's cooperation with its coaquifer states. The author suggests that China cooperates with its coaquifer states through such means as the exchange of data and information, joint monitoring, the conclusion of bilateral or multilateral aquifer agreements, the establishment of joint management mechanisms, and international technical cooperation. [ABSTRACT FROM AUTHOR]

China’s abundant transboundary water resources face new challenges as demands increase, internally and externally. As China seeks new ways to cooperate with its riparian neighbours, more attention is being paid to international water law in the evolving diplomatic practice across the region. China’s (mostly) bilateral transboundary water cooperation is here characterized as ‘responsive diplomacy’. This paper explores China’s state practice in this context and concludes by recommending that it moves from ‘responsive’ towards ‘preventive’ diplomacy. The author offers strategic and policy responses in order to effect this change. [ABSTRACT FROM AUTHOR]

The first asymmetric hydrogenation of unfunctionalized 2-substituted and 2,3-disubstituted 5,6-dihydropyrazines catalyzed by chiral cationic Ru-diamine complex ( R,R)- 1a was developed, affording chiral piperazine derivatives with good enantioselectivities (up to 89% ee). [ABSTRACT FROM AUTHOR]

• The efficacy of Jigucao capsule in treating Yanghuang syndrome rats was observed. • Metabolic abnormalities in Yanghuang syndrome rats were explored. • The metabolic regulation effect of Jigucao capsule on Yanghuang syndrome was evaluated for the first time. To explore the potential mechanism of the Chinese patent medicine Jigucao capsule in treating the serum metabolic profile of rats with Yanghuang syndrome, zingiber officinale Rosc. and ethanol simulates the syndrome background of traditional Chinese medicine and uses α-naphthyl isothiocyanate to induce liver damage in rats to prepare a Yanghuang syndrome model. The histopathological observation and the determination of biochemical indexes evaluate the therapeutic effect of the Jigucao capsule, and the metabolomic method analyzes the mechanism of the Jigucao capsule against Yanghuang syndrome. Jigucao capsule reduces the number of inflammatory cells, inhibits the proliferation of bile duct epithelial cells and hepatocyte necrosis. Compared with Yanghuang syndrome rats, the levels of alanine aminotransferase, alkaline phosphatase, and total bile acid were significantly reduced (P < 0.05). Furthermore, Jigucao capsule significantly reversed the abnormal levels of glucose 1-phosphate, phenylalanyl-cysteine, taurodeoxycholic acid, lysoPC (22:6 (4Z, 7Z, 10Z, 13Z, 16Z, 19Z), lysoPC (15:0), lysoPC (P-18:0), 7alpha-hydroxy-3-oxo-4-cholestenoate and 15(S)-hydroxyeicosatrieic acid and regulated part of the lipid metabolism and carbohydrate metabolism, Jigucao capsule has a therapeutic effect on Yanghuang syndrome rats. In short, this study sets for the first time elaborated on the underlying mechanism of Jigucao capsule resistance to Yanghuang syndrome rats from a metabolomics perspective, providing the basic data for the pharmacodynamic studies of the Jigucao capsule. [ABSTRACT FROM AUTHOR]

Sulfone group plays a pivotal role in narrowing emission spectra, while, precise modification with sulfone group for carbonyl‐based narrowband emitters that maintain high color purity remains challenging. Herein, a comprehensive exploration of the function of the sulfone group is performed with various sulfur valences and positions fused into traditional carbonyl‐based narrowband emission unit QAO, namely SpiroS‐QAO, SpiroSO2‐QAO, SpiroO‐QAO, and SpiroOSO2‐QAO. A rigid molecular skeleton with a spiro structure as an intramolecular lock enables the four emitters to exhibit narrowband emissions. After full oxidization of sulfur, the emission band of SpiroSO2‐QAO is further narrowed, with full width at half maximum of 32 nm, compared to that of 43 nm for sulfane‐decorated SpiroS‐QAO, which is attributed to the suppressed C─S bond‐length variation by the introduction of sulfone group. Nearly identical spectra of SpiroO‐QAO and SpiroOSO2‐QAO suggest that the sulfone group should be directly linked to the emission core to maximize its function. Maximum external quantum efficiencies of 30.8%, 30.3%, and 29.2% are achieved for SpiroO‐QAO, SpiroOSO2‐QAO, and SpiroS‐QAO‐based sensitized organic light‐emitting diodes with highly efficient thermally activated delayed fluorescence assistant host. These results offer a comprehensive understanding of the sulfone group embedded into the narrowband emission core with respect to the narrowing emission band. [ABSTRACT FROM AUTHOR]

Lead-free, mixed organic-inorganic cation, multifunctional applications, Thermochromism, ultrafast dynamics Turning Self-Trapped Exciton Emission to Near-Infrared Region in Thermochromism Zero-Dimensional Hybrid Metal Halides (Advanced Optical Materials 20/2023) Keywords: lead-free; mixed organic-inorganic cation; multifunctional applications; Thermochromism; ultrafast dynamics EN lead-free mixed organic-inorganic cation multifunctional applications Thermochromism ultrafast dynamics 1 1 1 10/24/23 20231015 NES 231015 B Turning Self-Trapped Exciton Emission to Near-Infrared Region in Thermochromism Zero-Dimensional Hybrid Metal Halides b In article number 2301110, Tianxin Bai, Junsheng Chen, and co-workers demonstrate a hybrid cation approach by using mixed organic-inorganic cations to develop a zero-dimensional metal halide with high thermal stability and solution processability, as well as multifunctional properties including thermochromic behavior and near infrared luminescence. [Extracted from the article]

DNA‐stabilized silver nanoclusters (DNA‐AgNCs) are easily tunable emitters with intriguing photophysical properties. Here, a DNA‐AgNC with dual emission in the red and near‐infrared (NIR) regions is presented. Mass spectrometry data showed that two DNA strands stabilize 18 silver atoms with a nanocluster charge of 12+. Besides determining the composition and charge of DNA2[Ag18]12+, steady‐state and time‐resolved methods were applied to characterize the picosecond red fluorescence and the relatively intense microsecond‐lived NIR luminescence. During this process, the luminescence‐to‐fluorescence ratio was found to be excitation‐intensity‐dependent. This peculiar feature is very rare for molecular emitters and allows the use of DNA2[Ag18]12+ as a nanoscale excitation intensity probe. For this purpose, calibration curves were constructed using three different approaches based either on steady‐state or time‐resolved emission measurements. The results showed that processes like thermally activated delayed fluorescence (TADF) or photon upconversion through triplet‐triplet annihilation (TTA) could be excluded for DNA2[Ag18]12+. We, therefore, speculate that the ratiometric excitation intensity response could be the result of optically activated delayed fluorescence. [ABSTRACT FROM AUTHOR]

DNA‐stabilized silver nanoclusters (DNA‐AgNCs) are easily tunable emitters with intriguing photophysical properties. Here, a DNA‐AgNC with dual emission in the red and near‐infrared (NIR) regions is presented. Mass spectrometry data showed that two DNA strands stabilize 18 silver atoms with a nanocluster charge of 12+. Besides determining the composition and charge of DNA2[Ag18]12+, steady‐state and time‐resolved methods were applied to characterize the picosecond red fluorescence and the relatively intense microsecond‐lived NIR luminescence. During this process, the luminescence‐to‐fluorescence ratio was found to be excitation‐intensity‐dependent. This peculiar feature is very rare for molecular emitters and allows the use of DNA2[Ag18]12+ as a nanoscale excitation intensity probe. For this purpose, calibration curves were constructed using three different approaches based either on steady‐state or time‐resolved emission measurements. The results showed that processes like thermally activated delayed fluorescence (TADF) or photon upconversion through triplet‐triplet annihilation (TTA) could be excluded for DNA2[Ag18]12+. We, therefore, speculate that the ratiometric excitation intensity response could be the result of optically activated delayed fluorescence. [ABSTRACT FROM AUTHOR]

The Yuquan capsules is a commonly used traditional Chinese Patent Medicine used for the treatment of diabetes mellitus. In this study, a high‐throughput analytical method for identifying the chemical composition of Yuquan capsules was established for the first time by using ultra‐performance liquid chromatography–quadrupole time of flight mass spectrometry. The data obtained were subjected to fragment analysis and this was combined with UNIFI processing of natural products. One‐hundred sixteen compounds were characterized from Yuquan capsules. Twelve of the bioactive compounds were quantitatively analyzed by ultra‐performance liquid chromatography‐tandem triple quadrupole mass spectrometry. This study was undertaken to obtain a comprehensive chemical profile analysis as well as to evaluate the overall quality of Yuquan capsules. The results will provide a reference for the quality evaluation of different Yuquan preparations. In addition, the data will enable basic pharmacodynamic research into these extensively used capsules. [ABSTRACT FROM AUTHOR]

The first asymmetric hydrogenation of 2-substituted and 2,3-substituted 5,6-dihydropyrazines catalyzed by a chiral cationic Ru-diamine complex affords chiral piperazine derivatives with good enantioselectivity and good yield. [ABSTRACT FROM AUTHOR]

Sulfone‐embedded heterocyclics are of great interest in organic light‐emitting diodes (OLEDs), however, exploring highly efficient narrowband emitters based on sulfone‐embedded heterocyclics remains challenging. Herein, five emitters with different sulfur valence state and molecular rigidity, namely tP, tCPD, 2tCPD, tPD and tPT, are thoroughly analysed. With restricted twisting of flexible peripheral phenyl by strengthening molecular rigidity, molecular emission spectra can be enormously narrowed. Further, introducing the sulfone group with bending vibration in low‐frequency region that suppresses high‐frequency vibration, sharp narrow full‐widths at half‐maximum of 28 and 25 nm are achieved for 2tCPD and tPD, respectively. Maximum external quantum efficiencies of 22.0 % and 27.1 % are successfully realized for 2tCPD‐ and tPD‐based OLED devices. These results offer a novel design strategy for constructing narrowband emitters by introducing sulfone group into a rigid molecular framework. [ABSTRACT FROM AUTHOR]

Sulfone‐embedded heterocyclics are of great interest in organic light‐emitting diodes (OLEDs), however, exploring highly efficient narrowband emitters based on sulfone‐embedded heterocyclics remains challenging. Herein, five emitters with different sulfur valence state and molecular rigidity, namely tP, tCPD, 2tCPD, tPD and tPT, are thoroughly analysed. With restricted twisting of flexible peripheral phenyl by strengthening molecular rigidity, molecular emission spectra can be enormously narrowed. Further, introducing the sulfone group with bending vibration in low‐frequency region that suppresses high‐frequency vibration, sharp narrow full‐widths at half‐maximum of 28 and 25 nm are achieved for 2tCPD and tPD, respectively. Maximum external quantum efficiencies of 22.0 % and 27.1 % are successfully realized for 2tCPD‐ and tPD‐based OLED devices. These results offer a novel design strategy for constructing narrowband emitters by introducing sulfone group into a rigid molecular framework. [ABSTRACT FROM AUTHOR]

A highly enantioselective synthesis of indolines by asymmetric hydrogenation of 1 H-indoles and 3 H-indoles at ambient temperature and pressure, catalyzed by chiral phosphine-free cationic ruthenium complexes, has been developed. Excellent enantio- and diastereoselectivities (up to >99 % ee, >20:1 d.r.) were obtained for a wide range of indole derivatives, including unprotected 2-substituted and 2,3-disubstituted 1 H-indoles, as well as 2-alkyl- and 2-aryl-substituted 3 H-indoles. [ABSTRACT FROM AUTHOR]

A highly enantioselective synthesis of indolines by asymmetric hydrogenation of 1 H-indoles and 3 H-indoles at ambient temperature and pressure, catalyzed by chiral phosphine-free cationic ruthenium complexes, has been developed. Excellent enantio- and diastereoselectivities (up to >99 % ee, >20:1 d.r.) were obtained for a wide range of indole derivatives, including unprotected 2-substituted and 2,3-disubstituted 1 H-indoles, as well as 2-alkyl- and 2-aryl-substituted 3 H-indoles. [ABSTRACT FROM AUTHOR]

Abrus mollis Hance is a traditional Chinese medicine that is widely used to treat acute and chronic hepatitis, steatosis, and fibrosis. Its therapeutic qualities of it have long been acknowledged, although the active ingredients responsible for its efficacy and the mechanisms of its action are unknown. In this study, the chemical constituents absorbed into the blood from Abrus mollis Hance were assessed by using liquid chromatography‐quadrupole‐time‐of‐flight mass spectrometry and the data was analyzed with the UNIFI screening platform. The results obtained were compared to existing chromatographic‐mass spectrometry information, including retention times and molecular weights as well as known reference compounds. 41 chemical constituents were found in Abrus mollis Hance, and these included 16 flavonoids, 13 triterpenoids, five organic acids, and two alkaloids. Experimentally it was found that Abrus mollis Hance had a therapeutic benefit when treating α‐naphthalene isothiocyanate‐induced acute liver injury in rats. In addition, 11 blood prototypical constituents, including six flavonoids, three triterpenoids, and two alkaloids, were found in serum samples following intragastric administration of Abrus mollis Hance extracts to rats. This novel study can be used for the quality control and pharmacodynamic assessment of Abrus mollis Hance in order to assess its efficacy in the therapeutic treatment of patients. [ABSTRACT FROM AUTHOR]

Objectives: Extended testing for high-risk human papillomavirus genotypes (hrHPVGTs) is increasingly investigated for risk stratification in cervical cancer screening.Methods: Age and hrHPVGT results from 16,993 women with atypical squamous cells of undetermined significance (ASC-US) cytology between November 2015 and August 2021 were studied and correlated with available histopathologic findings within 6 months.Results: High-risk human papillomavirus (hrHPV)-positive rate was 66.9% in women with ASC-US cytology, and the most prevalent genotypes were HPV 52 (20.9%), 16 (15.7%), and 58 (12.8%). Single hrHPV genotypes and multiple HPV genotypes were detected in 77.2% and 22.8% of women with hrHPV-positive results. Cervical intraepithelial neoplasia grade 2 or more (CIN2+) severe lesions were identified in 19.5% of women with hrHPV-positive ASC-US. The greatest risk for CIN2+ was found in single genotype infections with HPV 16 (33.1%), followed by women with multiple genotype infections, including HPV 16 (32.7%), 82 (30.8%), and 31 (30.0%). hrHPVGT testing for genotypes 16, 31, 35, 45, 82, 58, 33, 52, and 18 was identified in 91.9% (965/1,050) of CIN2+ cases, with 88.9% sensitivity, 43.2% specificity, positive predictive value of 23.9%, and negative predictive value of 95.1%.Conclusions: Extended hrHPV genotyping for women with ASC-US cytology could identify those hrHPV genotypes (HPV 16, 31, 35, 45, 82, 58, 33, 52, 18) associated with higher risk of CIN2+ and allows for refined risk stratification of women being screened. [ABSTRACT FROM AUTHOR]

Jigucao capsule is a well‐known Chinese patent medicine for the treatment of acute and chronic hepatitis and cholecystitis. The chemical components of Jigucao capsule were not clear resulting from the paucity of relevant studies, which hindered the research of the pharmacological mechanism, the comprehensive development, and utilization of Jigucao capsule in clinical studies. By establishing a high‐throughput ultra‐performance liquid chromatography quadrupole time of flight mass spectrometry in combination with intelligent UNIFI software data processing platform to automatically characterize and identify the chemical profile of Jigucao capsule, 144 compounds were determined rapidly, including 34 terpenoids, 25 flavonoids, 22 steroids, 21 phenylpropanoids, 10 glycosides, six alkaloids, 13 organic acids, and other 13 components. These compounds may be the active components of Jigucao capsule. In this study, a rapid and robust method for comprehensively analyzing the chemical composition of Jigucao capsule was described and established for the first time. The results will provide a reference for the quality control of Jigucao capsule and the establishment of a higher quality standard, as well as for the pharmacodynamic material basis research. [ABSTRACT FROM AUTHOR]

Abstract: Asymmetric hydrogenation of N-alkyl and N-aryl ketimines catalyzed by chiral cationic η6-arene-(N-monosulfonylated diamine) Ru(II) complexes has been investigated. Strong counteranion and solvent effects on the enantioselectivity were observed. The ruthenium catalyst bearing non-coordinating BArF− anion was found to be particularly effective for the hydrogenation of acyclic and exocyclic N-alkyl ketimines in the presence of (Boc)2O in dichloromethane or even under solvent-free conditions, providing chiral amines with up to >99% ee and full conversions. Alternatively, the ruthenium catalyst bearing achiral phosphate anion together with corresponding phosphoric acid as the additive was also efficient for the hydrogenation of N-alkyl ketimines in the absence of (Boc)2O with excellent enantioselectivities and full conversions. For N-aryl ketimines lower enantiomeric excesses were observed by using the ruthenium catalyst bearing BArF− anion. This catalytic protocol thus provides a facile and practical access to optically active amines and has been successfully employed in the gram-scale synthesis of enantiomerically pure (+)-sertraline. [Copyright &y& Elsevier]

A new kind of codendrimer consisting of a Fréchet-type dendron and a Tomalia-type PAMAM dendron has been synthesized via a liquid-phase approach, which could easily be purified using a simple precipitation method without the need for chromatographic separation. Functionalization at the periphery of a PAMAM dendron with bis(diphenylphosphinomethyl)amino groups led to a novel class of Janus dendritic phosphines. Their use as a recyclable homogeneous catalyst has been demonstrated with the Pd-catalyzed Suzuki coupling reaction. [ABSTRACT FROM AUTHOR]

• A new research framework for identifying the key Ecological nodes was proposed. • Achieved dynamic analysis on ecological networks and their components. • Weighted complex networks have been used to obtain ecological network topology information with higher credibility. • Rethinking landscape function from the perspective of animal movement. Regional ecological security is a pressing issue in the context of escalating human-environment conflicts. Ecological networks(ENs), the fundamental tool for characterizing ecosystems, have enabled further quantitative analysis at the micro level by integrating with complex networks in recent years. However, most studies neglect the unreliability of unweighted complex networks and the dynamic characteristics of ENs. This paper takes the Sichuan Basin as the research area and adopts the following methods. Firstly, it integrates landscape ecology and ecosystem services to construct the ENs using Linkage Mapper. Secondly, it introduces the cost-weighted distance as the weight to build complex networks and identifies potential pivot ecological sources and key ecological corridors based on the topological features of the weighted complex networks in 2000, 2010, and 2020. Thirdly, it applies circuit theory to detect ecological pinchpoints and ecological barrier points within the corridors as priority areas for ecological conservation and restoration. The results show that the ENs in the study area are denser on the northern and southern sides, and some ecological corridors change direction due to variations of resistance surfaces and landscape morphology. Through dynamic analysis of the weighted complex networks, 27 potential pivot ecological sources and 25 key ecological corridors are identified; then, 28 priority conservation areas and 10 priority restoration areas within these ecological corridors are extracted based on circuit theory. The study reveals a certain correlation between the distribution of ecological nodes and water bodies. Furthermore, comparing the weighted and unweighted complex network, we find that the weighted complex network is more reasonable, with 64.2% of ecological sources showing lower betweenness centrality than that in the unweighted network, reflecting the obstacles that urbanization poses to ecological networks. This study explores the impact of constantly changing resistance surfaces on the overall ENs and their components through dynamic analysis. The evolving topological features reflect the feedback of the ENs to external environmental changes, as well as the dynamic characteristics of the real ENs. Therefore, the findings of this study provide valuable references for ecological conservation and governance efforts in Sichuan Basin, promoting regional ecological security and the advancement of ecological civilization. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescent (TADF) materials generally suffer from severe concentration quenching. Efficient non‐doped TADF emitters are generally highly twisted aromatic amine‐based compounds with isolated chemical moieties. Herein we demonstrate that co‐facial packing and strong π–π intermolecular interactions give rise to bright TADF emissions in non‐doped film and crystalline states within the compound 2,4‐diphenyl‐6‐(thianthren‐1‐yl)‐1,3,5‐triazine (oTE‐DRZ). Quantum chemistry simulations indicate that a disperse outer orbital of sulfur atoms, a folded thianthrene plane (for a reduced donor–acceptor distance), and a triazine acceptor with n–π* character, generate a spatially conjugated transition with a small singlet–triplet splitting energy. In company with a highly emissive non‐doped film, the corresponding organic light‐emitting diode achieved a 20.6 % external quantum efficiency, verifying its potential for high‐performance optoelectronic applications. In a crystalline state, it was verified that intra‐ and intermolecular dual TADF assisted by a hidden room‐temperature phosphorescent state. This state could preserve the long‐lived excitons while suppressing non‐radiation, and it could serve as a "spring‐board" for cascade up‐conversion processes. The oTE‐DRZ crystal showed greenish‐blue emission with a very high photoluminescent quantum yield of approximately 87 %, which is the highest among all TADF crystals reported to date. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescent (TADF) materials generally suffer from severe concentration quenching. Efficient non‐doped TADF emitters are generally highly twisted aromatic amine‐based compounds with isolated chemical moieties. Herein we demonstrate that co‐facial packing and strong π–π intermolecular interactions give rise to bright TADF emissions in non‐doped film and crystalline states within the compound 2,4‐diphenyl‐6‐(thianthren‐1‐yl)‐1,3,5‐triazine (oTE‐DRZ). Quantum chemistry simulations indicate that a disperse outer orbital of sulfur atoms, a folded thianthrene plane (for a reduced donor–acceptor distance), and a triazine acceptor with n–π* character, generate a spatially conjugated transition with a small singlet–triplet splitting energy. In company with a highly emissive non‐doped film, the corresponding organic light‐emitting diode achieved a 20.6 % external quantum efficiency, verifying its potential for high‐performance optoelectronic applications. In a crystalline state, it was verified that intra‐ and intermolecular dual TADF assisted by a hidden room‐temperature phosphorescent state. This state could preserve the long‐lived excitons while suppressing non‐radiation, and it could serve as a "spring‐board" for cascade up‐conversion processes. The oTE‐DRZ crystal showed greenish‐blue emission with a very high photoluminescent quantum yield of approximately 87 %, which is the highest among all TADF crystals reported to date. [ABSTRACT FROM AUTHOR]

To date, blue dual fluorescence emission (DFE) has not been realized because of the limited choice of chemical moieties and severe geometric deformation of the DFE emitters leading to strong intramolecular charge transfer (ICT) with a large Stokes shift in excited states. Herein, an emitter (1′r,5′R,7′S)‐10‐(4‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl)‐10H‐spiro [acridine‐9,2′‐adamantane] (a‐DMAc‐TRZ) containing a novel adamantane‐substituted acridine donor is reported, which exhibits unusual blue DFE. The introduction of the rigid and bulky adamantane moiety not only suppressed the geometry relaxation in excited state, but also induced the formation of quasi‐axial conformer (QAC) and quasi‐equatorial conformer (QEC) geometries, leading to deep‐blue conventional fluorescence and sky‐blue thermally activated delayed fluorescence (TADF). The resulting organic light‐emitting diodes (OLEDs) achieved a maximum external quantum efficiency (EQE) of about 29 %, which is the highest reported for OLEDs based on dual‐conformation emitters. Tangled up in blue: The introduction of the rigid and bulky adamantane moiety leads to deep‐blue conventional fluorescence and sky‐blue thermally activated delayed fluorescence. The rigid backbone suppresses non‐radiative processes as well as the degenerate alignment arising from quasi‐axial conformers (QAC) and quasi‐equatorial conformers (QEC) geometries. [ABSTRACT FROM AUTHOR]

To date, blue dual fluorescence emission (DFE) has not been realized because of the limited choice of chemical moieties and severe geometric deformation of the DFE emitters leading to strong intramolecular charge transfer (ICT) with a large Stokes shift in excited states. Herein, an emitter (1′r,5′R,7′S)‐10‐(4‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl)‐10H‐spiro [acridine‐9,2′‐adamantane] (a‐DMAc‐TRZ) containing a novel adamantane‐substituted acridine donor is reported, which exhibits unusual blue DFE. The introduction of the rigid and bulky adamantane moiety not only suppressed the geometry relaxation in excited state, but also induced the formation of quasi‐axial conformer (QAC) and quasi‐equatorial conformer (QEC) geometries, leading to deep‐blue conventional fluorescence and sky‐blue thermally activated delayed fluorescence (TADF). The resulting organic light‐emitting diodes (OLEDs) achieved a maximum external quantum efficiency (EQE) of about 29 %, which is the highest reported for OLEDs based on dual‐conformation emitters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coexistence of intra-CT and inter-CT processes is realized for DPA-XA-TRZ. • Dual CT processes can be simultaneously enhanced by planar molecular skeleton. • Organic light-emitting diodes with external quantum efficiency of 21.9% is realized. • Efficiency of 31.7% is realized by DPA-XA-TRZ sensitized device with DMAc-BN dopant. Intramolecular charge transfer (intra-CT) and intermolecular charge transfer (inter-CT) are two general molecular design strategies of thermally activated delayed fluorescence (TADF) materials for organic light-emitting diodes (OLEDs). Herein, a diphenylamine (DPA) donor and a 2,4-diphenyl-1,3,5-triazine (TRZ) acceptor are connected by two planar units, non-conjugated 9,9-dimethyl-9 H -xanthene (XA) and conjugated dibenzo[ b,d ]furan (FR), to give D-σ-A type emitter DPA-XA-TRZ and D-π-A type emitter DPA-FR-TRZ. Coexistence of intra- and inter-CT is found for DPA-XA-TRZ and is readily tuned by various doping concentrations owing to the non-conjugated linkage. In contrast, DPA-FR-TRZ shows a dominant intra-CT characteristic due to the strong molecular conjugation. The planar molecular skeleton of DPA-XA-TRZ could not only enhance intramolecular electronic coupling, but also reduce steric hindrance and shorten intermolecular distance to enhance inter-CT process. A maximum external quantum efficiency (EQE max) of 21.9 % is achieved for the OLED device based on DPA-XA-TRZ, which is 2.5 times higher than that of DPA-FR-TRZ (8.4 %). DPA-XA-TRZ can also be utilized as an assistant host to sensitize multiple resonance TADF emitter DMAc-BN, and an EQE max of 31.7 % is realized owing to its dual CT processes and high reverse intersystem crossing rate (k RISC), which is significantly superior to the conventional mCBP host and mCBP:PO-T2T exciplex cohost. [ABSTRACT FROM AUTHOR]

A series of tunable G0-G3 dendritic 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP) ligands was prepared by attaching polyaryl ether dendrons onto the four phenyl rings on the P atoms. Their ruthenium complexes were employed in the asymmetric hydrogenation of β-ketoesters, α-ketoesters, and α-ketoamides to reveal the effects of dendron size on the catalytic properties. The second- and third-generation catalysts exhibited excellent enantioselectivities, which are remarkably higher than those obtained from the small molecular catalysts and the first-generation catalyst. Molecular modeling indicates that the incorporation of bulky dendritic wedges can influence the steric environments around the metal center. In addition, the ruthenium catalyst bearing a second-generation dendritic ligand could be recycled and reused seven times without any obvious decrease in enantioselectivity. [ABSTRACT FROM AUTHOR]

Front Cover: Rapid characterization of the constituents in Jigucao capsule using ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry A rapid and robust method was established by high-throughput ultra high performance liquid chromatography with quadrupole time of flight mass spectrometry. DOI: 10.1002/jssc.202100664 The cover picture shows the qualitative analysis of Jigucao capsule (JGCC), a well-known Chinese Patent Medicine for the treatment of acute and chronic hepatitis and cholecystitis. [Extracted from the article]

Highlights: [•] Dendritic catalysts with a ‘Sandwich’ multi-layer structure have been synthesized. [•] The catalysts have good performance in the hydrogenation of simple aryl ketones. [•] These dendritic catalysts could be reused for nine times by solvent precipitation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Luminous mechanism switch between TADF and CF was realized by isomer engineering. • Different exciton dynamic processes depend on the interplay of 1CT, 3LE and 3CT and molecular geometry rigidity. • Red TADF OLEDs with external quantum efficiency >20% was achieved. Marching toward highly efficient long-wavelength organic light-emitting diodes (OLEDs) is paramount but formidable challenge, and rational manipulation of molecular configuration and excited state dynamic processes are of great importance to harvest dark triplet exciton and suppress non-radiative transition for excellent light emission properties. Herein, we introduced a novel electron acceptor 11H-indeno [1,2-b] quinoxalin-11-one (IQ) as a building-block to construct two bright red light-emitting regioisomers of IQ-oTPA and IQ-pTPA, which exhibit entirely different exciton dynamic processes of thermally activated delayed fluorescence (TADF) and conventional fluorescence (CF) respectively. According to theoretical calculation and photophysical characterization, the energy gap, energy level alignment and spin–orbit coupling (SOC) effects of charge-transfer singlet state (1CT), local excited triplet state (3LE) and charge-transfer triplet state (3CT) together with the molecular geometry rigidity play a critical role in the triplet exciton up-conversion processes. Maximum external quantum efficiencies of 20.6% and 3.5% with emission peaks of 604 and 642 nm were achieved for the proof-of-concept electroluminescent devices based on IQ-oTPA and IQ-pTPA respectively, which are among the state-of-the-art performance for red-emission TADF and CF OLEDs and provide new insights for the molecular design tactic of high-performance red OLEDs. [ABSTRACT FROM AUTHOR]

Various complexes bearing different counterions are investigated and (I) is demonstrated to be the most effective one. [ABSTRACT FROM AUTHOR]

A PHOX with arms: A series of dendrimers with Ir phosphinooxazoline (PHOX) cores were designed and synthesized and found to be highly effective and recoverable catalysts for asymmetric hydrogenation of 2,4 ‐ diaryl ‐ 1,5 ‐ benzodiazepines. An obvious positive dendritic effect on reactivity was observed, leading to chiral nitrogen ‐ containing heterocycles with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Two poly(benzyl ether) dendrons, decorated in their periphery with nitrile groups, were divergently synthesized and fully characterized. Their gelation properties were studied by using scanning electron microscopy (SEM), X-ray crystal structure analysis and concentration- and temperature-dependent H NMR spectroscopy. It was found that the gelation capability of these dendrons was highly dependent on dendron generation, and the second-generation dendron G-CN proved to be highly efficient organogelator despite the lacking of any conventional gelation motifs, such as amides, long alkyl side chains and steroidal groups. The multiple strong π-π stacking interactions and hydrogen bonding interactions due to the peripheral isophthalonitrile motifs were proved to be the main driving forces to form the self-assembled gel. [ABSTRACT FROM AUTHOR]

A new kind of chiral diphosphine PyrPhos-functionalized codendrimers have been synthesized via a liquid-phase strategy in high yields. The resulting dendrimeric PyrPhos ligands were purified by a simple solvent precipitation without the need for chromatographic separation, and well characterized by 1H, 13C and 31P NMR, MALDI-TOF mass spectroscopy as well as elemental analysis. Their rhodium complexes were applied to the asymmetric hydrogenation of α-acetamido cinnamic acids. Excellent enantioselectivities were achieved, which are comparable to those with the corresponding small molecular catalysts. In addition, these codendrimeric catalysts showed better catalytic performance than the dendrimeric catalysts with Rh(PyrPhos) sites located in the focal point of poly(aryl ether) dendrons or in the periphery of poly(propyleneimine) dendrimers. [ABSTRACT FROM AUTHOR]