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1.
Microorganisms ; 12(5)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38792781

RESUMO

Heavy metal resistance mechanisms and heavy metal response genes are crucial for microbial utilization in heavy metal remediation. Here, Corynebacterium crenatum was proven to possess good tolerance in resistance to copper. Then, the transcriptomic responses to copper stress were investigated, and the vital pathways and genes involved in copper resistance of C. crenatum were determined. Based on transcriptome analysis results, a total of nine significantly upregulated DEGs related to metal ion transport were selected for further study. Among them, GY20_RS0100790 and GY20_RS0110535 belong to transcription factors, and GY20_RS0110270, GY20_RS0100790, and GY20_RS0110545 belong to copper-binding peptides. The two transcription factors were studied for the function of regulatory gene expression. The three copper-binding peptides were displayed on the C. crenatum surface for a copper adsorption test. Furthermore, the nine related metal ion transport genes were deleted to investigate the effect on growth in copper stress. This investigation provided the basis for utilizing C. crenatum in copper bioremediation.

2.
J Biochem Mol Toxicol ; 38(4): e23693, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622980

RESUMO

IGSF10, a protein that belongs to the immunoglobulin superfamily, is involved in regulating the early migration of neurons that produce gonadotropin-releasing hormone and performs a fundamental function in development. Our previous study confirmed that the mRNA expression level of IGSF10 may be a protective prognosis factor for lung adenocarcinoma (LUAD) patients. However, the specific mechanisms of IGSF10 are still unclear. In this research, it was shown that the protein level of IGSF10 was down-modulated in LUAD tissues and had a link to the clinical and pathological characteristics as well as the patient's prognosis in LUAD. Importantly, IGSF10 regulates the metastatic ability of LUAD cells in vitro and in vivo. It was proven in a mechanistic sense that IGSF10 inhibits the capacity of LUAD cells to metastasize through the Spi-B/Integrin-ß1 signaling pathway. These findings gave credence to the premise that IGSF10 performed a crucial function in LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Integrinas/genética , Integrinas/metabolismo , Neoplasias Pulmonares/metabolismo , Transdução de Sinais
3.
Chemistry ; 29(44): e202300554, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37249393

RESUMO

The field of anion supramolecular chemistry has received more and more attention in recent years. Anions with diverse types and geometries have been widely used for the synthesis of ionic spin crossover (SCO) complexes. This review is devoted to anion effects on the molecular, supramolecular structures and magnetic properties of discrete SCO compounds. Firstly, typical anions used in the synthesis of these compounds are briefly summarized according to their various geometries. This is followed by a collection of representative examples of anion-based SCO compounds, whose SCO properties are analyzed in terms of supramolecular interactions, geometry and charge of anions. In the third part, anion effects on SCO complexes of different kinds of metal centers and ligands are outlined and finally remarks on the synthesis new type of ionic SCO complexes in the future are described.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36673938

RESUMO

Fine particulate matter (PM2.5) pollution brings great negative impacts to human health and social development. From the perspective of heterogeneity and the combination of national and urban analysis, this study aims to investigate the variation patterns of PM2.5 pollution and its determinants, using geographically and temporally weighted regression (GTWR) in 273 Chinese cities from 2015 to 2019. A comprehensive analytical framework was established, composed of 14 determinants from multi-dimensions, including population, economic development, technology, and natural conditions. The results indicated that: (1) PM2.5 pollution was most severe in winter and the least severe in summer, while the monthly, daily, and hourly variations showed "U"-shaped, pulse-shaped and "W"-shaped patterns; (2) Coastal cities in southeast China have better air quality than other cities, and the interaction between determinants enhanced the spatial disequilibrium of PM2.5 pollution; (3) The determinants showed significant heterogeneity on PM2.5 pollution-specifically, population density, trade openness, the secondary industry, and invention patents exhibited the strongest positive impacts on PM2.5 pollution in the North China Plain. Relative humidity, precipitation and per capita GDP were more effective in improving atmospheric quality in cities with serious PM2.5 pollution. Altitude and the proportion of built-up areas showed strong effects in western China. These findings will be conductive to formulating targeted and differentiated prevention strategies for regional air pollution control.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Cidades , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Poluição do Ar/análise , China
5.
ACS Appl Bio Mater ; 5(11): 5041-5056, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36260917

RESUMO

Electrochemistry has become a powerful strategy to modulate cellular behavior and biological activity by manipulating electrical signals. Subsequent electrical stimulus-responsive conducting polymers (CPs) have advanced traditional wired electrochemical stimulation (ES) systems and developed wireless cell stimulation systems due to their electroconductivity, biocompatibility, stability, and flexibility. Bipolar electrochemistry (BPE), i.e., wireless electrochemistry, offers an effective pathway to modify wired ES systems into a desirable contactless mode, turning out a potential technique to offer fundamental insights into neural cell stimulation and neural network formation. This review commences with a brief discussion of the BPE technique and also the advantages of a bipolar electrochemical stimulation (BPES) system compared to traditional wired ES systems and other wireless ES systems. Then, the BPES system is elucidated through four aspects: the benefits of BPES, the key factors to establish BPES platforms for cell stimulation, the limits/barriers to overcome for current rigid materials in particular metals-based systems, and a brief overview of the concept proved by CPs-based systems. Furthermore, how to refine the existing BPES system from materials/devices modification that combine CP compositions with 3D fabrication/bioprinting technologies is elaborately discussed as well. Finally, the review ends together with future research directions, picturing the potential of BPES system in biomedical applications.


Assuntos
Polímeros , Polímeros/química , Eletroquímica
6.
Data Brief ; 43: 108393, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35781980

RESUMO

Data in this article is associated with our research article "Enhanced wireless cell stimulation using soft and improved bipolar electroactive conducting polymer templates" Qin et al. (2022). Primarily, the present article shows the data of PPy-PMAS/FTO, PPy-PMAS-collagen/FTO and PPy-PMAS-DS-collagen/FTO in conventional electrochemical process and bipolar electrochemical process along with in situ spectrometry for comprehensive supplement and comparison to help with better developing modified conducting polymers based bipolar electrochemistry. Secondly, the presented the complete dataset useful for modelling the soft and improved bipolar electroactive conducting polymers focusing on wireless cell (animal and human) stimulation, which are reported in the main article. All data reported were analysed using Origin 2019b 64Bit.

7.
Sci Total Environ ; 837: 155687, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35525362

RESUMO

Identifying the underlying ecological drivers of macroinvertebrate community assembly is fundamental to metacommunity ecology. Comparably, determining the influence of different drivers on beta diversity patterns can provide insight into processes governing community organization. Exploring the ecological drivers of metacommunity and beta diversity are major avenues to improve bioassessment, restoration, and river management, which are still poorly explored in China, especially in subtropical highly developed river networks. To address this gap, we use a dataset (macroinvertebrate communities and environmental variables) collected from the Yangtze River Delta, China to test the above ideas. We used the K-means clustering method to divide 405 river sites into three anthropogenic impacted groups, nearly pristine sites, moderately impacted sites, and heavily impacted sites, and subsequently used partial Mantel tests to investigate how species sorting and dispersal shaped the metacommunity that varied with the levels of anthropogenic impacts and to explore the responses of different components of beta diversity to environmental and spatial distances among sites for each group. Our results revealed that both species sorting and dispersal shape communities, but the importance of species sorting and dispersal varied with the levels of anthropogenic impacts. Nearly pristine sites were mostly shaped only by species sorting, while heavily impacted sites were shaped by dispersal. We also found that turnover was by far the dominant component of beta diversity across all levels of impact. Therefore, we encourage that environmental variables and spatial processes should be considered in bioassessment approaches. In addition, it is essential to focus on maintaining habitat heterogeneity and identifying and protecting regional species pools that could improve local biodiversity through dispersal for ecosystem management of the Yangtze River Delta of China.


Assuntos
Ecossistema , Rios , Biodiversidade , China
8.
Chemosphere ; 301: 134640, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35439486

RESUMO

Identifying the effects of meteorological conditions on PM2.5 pollution is of great significance to explore methods to reduce atmospheric pollution. This study attempts to analyze the spatiotemporal variations of PM2.5 pollution and its dynamic nexus with meteorological factors in the Beijing-Tianjin-Hebei (BTH) region from 2015 to 2020 using standard deviation ellipse (SDE) and panel vector autoregressive (PVAR) model. The results indicate that: (1) In 2015-2020, PM2.5 pollution decreased significantly, indicating air pollution control policies in China have taken effect; Also, it showed a cumulative effect, or there was the path dependence of air pollution. (2) PM2.5 pollution presented a distribution pattern from northeast to southwest, while the directionality of air pollution has weakened. Based on SDE, PM2.5 pollution in Cangzhou can reflect the average level in the BTH; (3) Meteorological conditions exhibited a lagged and sustained effect on PM2.5 pollution. Specifically, the effects of meteorological factors on PM2.5 presented disequilibrium over time. In the long run, precipitation and temperature mainly showed negative impacts on PM2.5 pollution, while wind speed, relative humidity and sunshine duration aggravated PM2.5 pollution in the BTH. This study contributes to extending the study on the spatiotemporal evolution of PM2.5 pollution and its links with meteorological conditions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , China , Monitoramento Ambiental/métodos , Material Particulado/análise
9.
Bioengineered ; 13(3): 7168-7180, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35285407

RESUMO

Studies have revealed the relationship between histone deacetylases (HDACs)/microRNAs (miRNAs) and sepsis, but little has ever investigated the mechanism of HDAC1/miR-124-5p in sepsis. Herein, we studied the impacts of HDAC1/miR-124-5p on myocardial damage of septic mice via regulating high-mobility group box chromosomal protein 1 (HMGB1). Septic mice were induced by cecal ligation and puncture. HDAC1, miR-124-5p and HMGB1 expression in myocardial tissues of septic mice were detected. Septic mice were injected with HDAC1 low expression-, miR-124-5p high expression- or HMGB1 low expression-related structures to observe cardiac function, inflammatory response, oxidative stress response, myocardial pathological changes and apoptosis in myocardial tissues of septic mice. The relationship of HDAC1/miR-124-5p/HMGB1 was verified. HDAC1 and HMGB1 expression were upregulated while miR-124-5p expression was decreased in myocardial tissues of septic mice. Restored miR-124-5p/depleted HDAC1 or HMGB1 recovered the cardiac function, improved cardiac function, inflammatory response, oxidative stress response, myocardial pathological changes and inhibit ed cardiomyocyte apoptosis in septic mice. HDAC1 bound to miR-124-5p which directly targeted HMGB1. This study suggests that down-regulated HDAC1 or up-regulated miR-124-5p recovers myocardial damage of septic mice via decreasing HMGB1.


Assuntos
Proteína HMGB1 , Histona Desacetilase 1/metabolismo , MicroRNAs/genética , Sepse , Animais , Apoptose/genética , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Camundongos , MicroRNAs/metabolismo , Miocárdio/metabolismo , Sepse/metabolismo
10.
Macromol Rapid Commun ; 43(6): e2200001, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35065001

RESUMO

Solar induced thermal energy is a vital heat source supplementing body heat to realize thermo-to-electric energy supply for wearable electronics. Thermo-electrochemical cells, compared to the widely investigated thermoelectric generators, show greater potential in wearable applications due to the higher voltage output from low-grade heat and the increased option range of cheap and flexible electrode/electrolyte materials. A wearable photo-thermo-electrochemical cell (PTEC) is first fabricated here through the introduction of a polymer-based flexible photothermal film as a solar-absorber and hot electrode, followed by a systematic investigation of wearable device design. The as-prepared PTEC single device shows outstanding output voltage and current density of 15.0 mV and 10.8 A m-2 and 7.1 mV and 8.57 A m-2 , for the device employing p-type and n-type gel electrolytes, respectively. Benefiting from the equivalent performance in current density, a series connection containing 18 pairs of p-n PTEC devices is effectively made, which can harvest solar energy and charge supercapacitors to above 250 mV (1 sun solar illumination). Meanwhile, a watch-strap shaped flexible PTEC (eight p-n pairs) that can be worn on a wrist is fabricated and the realized voltage above 150 mV under light shows the potential for use in wearable applications.


Assuntos
Energia Solar , Dispositivos Eletrônicos Vestíveis , Eletrodos , Eletrólitos , Eletrônica
11.
Dalton Trans ; 50(42): 15210-15223, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34622889

RESUMO

A series of Fe(III) complexes [Fe(5-F-sal-N-1,4,7,10)]Y (Y = PF6- for 1, Y = ClO4- for 2, Y = I- for 3 and Y = NO3- for 4) have been prepared. Single-crystal X-ray crystallographic studies show that complex 1 crystallizes in the orthorhombic Pna21 space group and complexes 2-4 have an isomorphous structure and crystallize in the same monoclinic space group, P21/n. Complexes 2-4 have two independent molecules (Fe1 and Fe2) in the unit cell. Magnetic susceptibility measurements demonstrated that complexes 1 and 3 showed a gradual one-step SCO behavior (T1/2 for 1 = 177 K and for 3 = 227 K) without thermal hysteresis. The magnetic behavior of 2 shows an incomplete two-step SCO process at T1/2 = 114 K and 170 K, respectively, while 4 is in a high-spin state at all measured temperatures. A careful evaluation of the supramolecular structures of these complexes revealed correlation between the supramolecular packing forces and their SCO behavior. The crystal structure of 1 consists of a three-dimensional (3D) extended network constructed from N-H⋯F and C-H⋯F hydrogen bonds, and C-H⋯π and C⋯C short contacts. In compounds 2-4, the crystal packing is governed by C⋯C, C-H⋯π and p-π interactions for the Fe1 centers and by C-H⋯π/O interactions for the Fe2 centers, which form 1D chains. Additional interactions (C-H⋯F and N-H⋯O/I) connect the neighboring chains and planes to form a complex supramolecular network. The anion⋯π interactions in 4 provide a means for preventing SCO occurring at low temperatures. This suggests that the supramolecular connectivity of the anions influences the magnetic properties.

12.
Dalton Trans ; 50(17): 5899-5910, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33949401

RESUMO

The effect of counter anions on thermally induced manganese(iii)-based SCO within the [Mn(5-F-sal-N-1,5,8,12)]Y family has been investigated. All the complexes are crystallized without any lattice solvents. Crystal packing and intermolecular forces influence the spin-state stabilization and spin-transition profiles. Magnetic measurements indicate that salts with octahedral anions, [Mn(5-F-sal-N-1,5,8,12)]PF6 (1), [Mn(5-F-sal-N-1,5,8,12)]AsF6 (2) and [Mn(5-F-sal-N-1,5,8,12)]SbF6 (3), show HS electronic configurations between 2 and 300 K, and there exist π-π stackings between the phenyl groups from the neighboring [Mn(5-F-sal-N-1,5,8,12)]+ cations. As for the tetrahedral anions, complex [Mn(5-F-sal-N-1,5,8,12)]BF4 (4) exhibits a gradual and incomplete spin conversion. Complex [Mn(5-F-sal-N-1,5,8,12)] ClO4 (5) shows a nearly complete SCO with T1/2 = 100 K. The remaining salts with spherical anions form Nam-HX (X = Cl, Br, I) hydrogen bonds between Mn(iii) cations and counterions. Complexes [Mn(5-F-sal-N-1,5,8,12)]Cl (6) and [Mn(5-F-sal-N-1,5,8,12)] Cl0.28Br0.72 (7) feature gradual SCO behaviors with T1/2 = 220 K and 235 K, respectively. Complex [Mn(5-F-sal-N-1,5,8,12)]I (8) exhibits a more gradual spin conversion and is far from a complete HS state with a χMT value of 1.89 cm3 mol-1 K at 400 K.

13.
Inflammation ; 44(5): 2044-2053, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34041646

RESUMO

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an independent risk factor for mortality in patients with sepsis. In this study, we attempt to investigate the molecular mechanism of circANKRD36 underlying sepsis-induced ALI/ARDS in vitro. We first detected the altered circRNAs in serums of patients with sepsis-induced ARDS using circRNAs microarray. CircANKRD36 expression in serums and LPS-stimulated RAW264.7 cells was measured using qRT-PCR. CCK-8, cell migration, ELISA, and qRT-PCR were applied to the evaluation of cell biological behavior and inflammation reaction. The results showed that circANKRD36 expression was significantly elevated in serum of patients with sepsis-induced ARDS. Knockdown of circANKRD36 inhibited cell viability and migration and alleviated inflammation of lipopolysaccharide-stimulated (LPS-stimulated) RAW264.7 cells. Bioinformatic analysis demonstrated that circANKRD36 serves as a sponge for miR-330 and ROCK1 was directly targeted by miR-330. Furthermore, knockdown of circANKRD36 repressed ROCK1 expression by targeting miR-330. In short, circANKRD36 knockdown suppressed cell viability and migration of LPS-stimulated RAW264.7 cells in vitro via sponging miR-330, which may provide new ideas for the treatment of sepsis-induced ARDS.


Assuntos
Movimento Celular/fisiologia , Técnicas de Silenciamento de Genes/métodos , Lipopolissacarídeos/toxicidade , MicroRNAs/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Animais , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , MicroRNAs/genética , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Células RAW 264.7 , Síndrome do Desconforto Respiratório/genética , Síndrome do Desconforto Respiratório/metabolismo
14.
Angew Chem Int Ed Engl ; 60(12): 6744-6751, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33289262

RESUMO

Chiral framework materials have been developed for many applications including chiral recognition, chiral separation, asymmetric catalysis, and chiroptical materials. Herein, we report that an achiral cucurbit[8]uril-based supramolecular organic framework (SOF-1) with the dynamic rotational conformation of tetraphenylethene units can exhibit adaptive chirality to produce M-SOF-1 or P-SOF-1 with mirror-image circular dichroism (CD) with gabs ≈±10-4 and circularly polarized luminescence (CPL) with glum ≈±10-4 induced by L-/D-phenylalanine in water, respectively. The chirality induction in CD (gabs ≈-10-4 ) and CPL (glum ≈-10-4 ) of P-SOF-1 from achiral SOF-1 can be presented by using a small amount of adenosine-5'-triphosphate disodium (ATP) or adenosine-5'-diphosphate disodium (ADP) (only 0.4 equiv) in water. Furthermore, the adaptive chirality of SOF-1 can be used to determine dipeptide sequences (e.g., Phe-Ala and Ala-Phe) and distinguish polypeptides/proteins (e.g., somatostatin and human insulin) with characteristic CD spectra. Therefore, achiral SOF-1 as an ideal chiroptical platform with adaptive chirality may be applied to determine the enantiopurity of amino acids (e.g., L-/D-phenylalanine), develop aqueous CPL materials, and distinguish biological chiral macromolecules (e.g., peptides/proteins) via chirality induction in water.

15.
J Immunol Res ; 2020: 6644687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33294466

RESUMO

The remodeling of the extracellular matrix (ECM) in the parenchyma plays an important role in the development of acute respiratory distress syndrome (ARDS), a disease characterized by lung injury. Although it is clear that TGF-ß1 can modulate the expression of the extracellular matrix (ECM) through intracellular signaling molecules such as Smad3, its role as a therapeutic target against ARDS remains unknown. In this study, a rat model was established to mimic ARDS via intratracheal instillation of lipopolysaccharide (LPS). A selective inhibitor of Smad3 (SIS3) was intraperitoneally injected into the disease model, while phosphate-buffered saline (PBS) was used in the control group. Animal tissues were then evaluated using histological analysis, immunohistochemistry, RT-qPCR, ELISA, and western blotting. LPS was found to stimulate the expression of RAGE, TGF-ß1, MMP2, and MMP9 in the rat model. Moreover, treatment with SIS3 was observed to reverse the expression of these molecules. In addition, pretreatment with SIS3 was shown to partially inhibit the phosphorylation of Smad3 and alleviate symptoms including lung injury and pulmonary edema. These findings indicate that SIS3, or the blocking of TGF-ß/Smad3 pathways, could influence remodeling of the ECM and this may serve as a therapeutic strategy against ARDS.


Assuntos
Matriz Extracelular/metabolismo , Isoquinolinas/farmacologia , Lipopolissacarídeos/efeitos adversos , Piridinas/farmacologia , Pirróis/farmacologia , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/metabolismo , Animais , Biomarcadores , Colágeno , Modelos Animais de Doenças , Expressão Gênica , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Ratos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Síndrome do Desconforto Respiratório/diagnóstico , Proteína Smad3/antagonistas & inibidores , Fator de Crescimento Transformador beta1/metabolismo
16.
Data Brief ; 33: 106406, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33088881

RESUMO

Data in this article is associated with our research article "Bipolar Electroactive Conducting Polymers for Wireless Cell Stimulation" [1]. Primarily, the present article shows the data of PPy-pTS, PPy-DS and PPy-DS/collagen in conventional electrochemical process and bipolar electrochemical process for comprehensive supplement and comparison to help with better understanding and developing conducting polymers based bipolar electrochemistry. Secondly, the presented data of bipolar electrostimulation (BPES) protocol development constitute the complete dataset useful for modeling the bipolar electroactive conducting polymers focusing on wireless cell stimulation, which are reported in the main article. All data reported were analysed using Origin 2018b 64Bit.

17.
Dalton Trans ; 49(14): 4293-4305, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32159185

RESUMO

This paper reports the syntheses, crystal structures and magnetic properties of spin crossover (SCO) salts of formulae [Mn(naphth-sal-N-1,5,8,12)]SbF6 (1), [Mn(naphth-sal-N-1,5,8,12)]AsF6 (2), [Mn(naphth-sal-N-1,5,8,12)]PF6·1/2CH3OH (3) and [Mn(naphth-sal-N-1,5,8,12)]ClO4 (4), where (naphth-sal-N-1,5,8,12)2- (2,2'-((1E,14E)-2,6,10,14-tetraazapentadeca-1,14-diene-1,15-diyl)diphenolate) is a big conjugated hexadentate Schiff-base ligand. Magnetic susceptibility measurements demonstrated that complexes 1 and 2 showed a gradual one-step SCO between the high-spin (HS, S = 2) and low-spin (LS, S = 1) states without thermal hysteresis. The transition temperatures T1/2 of the SbF6 (1) and AsF6 (2) salts estimated from the magnetic susceptibility measurements are 164 and 171 K, respectively. The existence of the crystal solvent of complex 3 changes the supramolecular packing, leading to close ππ stacking interactions between the phenyl groups of the ligands. These close stacking interactions hinder the flexibility of the whole ligand, precluding the spin transformation of complex 3 and leading to its stabilization in the HS state in the temperature range of 2-300 K. For 4, crystal structure analysis indicates that the reduction in the anion size leads to close contacts between the naphthalene rings. These C-Hπ interactions provide a means for preventing the spin crossover occurring at low temperatures.

18.
ACS Appl Mater Interfaces ; 11(50): 46746-46755, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31738045

RESUMO

Freestanding flexible electrodes with high areal mass loading are required for the development of flexible high-performance lithium-ion batteries (LIBs). Currently they face the challenge of low mass loading due to the limited concentrations attainable in processable dispersions. Here, we report a simple low-temperature hydrothermal route to fabricate flexible layered molybdenum disulfide (MoS2)/reduced graphene oxide (MSG) films offering high areal capacity and good lithium storage performance. This is achieved using a self-assembly process facilitated by the use of liquid crystalline graphene oxide (LCGO) and commercial MoS2 powders at a low temperature of 70 °C. The amphiphilic properties of ultralarge LCGO nanosheets facilitates the processability of large-size MoS2 powders, which is otherwise nondispersible in water. The resultant film with an areal mass of 8.2 mg cm-2 delivers a high areal capacity of 5.80 mAh cm-2 (706 mAh g-1) at 0.1 A g-1. This simple method can be adapted to similar nondispersible commercial battery materials for films fabrication or production of more complicated constructs via advanced fabrication technologies.

19.
Dalton Trans ; 48(35): 13305-13314, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31429837

RESUMO

Two novel phosphorescent Ir(iii) complexes, Ir(fom)2(pic) and Ir(fof)2(pic), containing fluorene oxadiazole groups have been synthesized and characterized. The photophysical properties of the complexes have been investigated. Interestingly, both complexes exhibited aggregation-induced phosphorescent emission. The X-ray diffraction study showed that the AIPE properties resulted from weak π-π and C-HN hydrogen-bonding interactions in the aggregated state restricting the rotation of the phenyl groups in the cyclometalating ligands. Owing to the sensitive and selective luminescence quenching of the complexes using picric acid (PA), the complexes were used for PA detection in aqueous media. Additionally, electroluminescence devices have been fabricated using the complexes at 5%-30% doping concentrations. The devices based on Ir(fof)2(pic) obtained the highest luminance 11 877 cd m-2 and current efficiency 23.2 cd A-1, which implied that the incorporation of fluorine could improve the electron affinity and ameliorate the capability of electron injection or transporting.

20.
J Am Chem Soc ; 141(21): 8412-8415, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31026395

RESUMO

Here we report one-pot synthesis of tetraphenylethene-based tetracationic dicyclophane (1) and its self-assembly behaviors with aggregation-induced emission (AIE) and light-harvesting function. Confirmed by X-ray crystal structure and high resolution transmission electron microscopy, this tetracationic dicyclophane can self-assemble into a 3D supramolecular framework to form crystalline nanospheres (2) finally, which exhibits a strong emission (ΦF = 97.7%) via AIE effect in aqueous solution. Interestingly, AIE-active 2 as a single-molecule-based fluorescent supramolecular platform can encapsulate an organic dye (e.g., Nile red) to form light-harvesting nanospheres (3) further with a large red-shift (Δλ = ∼70 nm), highly efficient energy-transfer ability (ΦET = 77.5%), and high antenna effect (14.3).

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