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Aqueous zinc-ion batteries (ZIBs) are the new generation electrochemical energy storage systems. Recently, two-dimensional conductive metal-organic frameworks (2D c-MOFs) are attractive to serve as cathode materials of ZIBs due to their compositional diversity, abundant active sites, and excellent conductivity. Despite the growing interest in 2D c-MOFs, their application prospects are still to be explored. Herein, a tetraoxa[8]circulene (TOC) derivative with unique electronic structure and interesting redox-active property are synthesized to construct c-MOFs. A series of novel 2D c-MOFs (Cu-TOC, Zn-TOC and Mn-TOC) with different conductivities and packing modes are obtained by combining the linker tetraoxa[8]circulenes-2,3,5,6,8,9,11,12-octaol (8OH-TOC) and corresponding metal ions. Three c-MOFs all exhibit typical semiconducting properties, and Cu-TOC exhibits the highest electrical conductivity of 0.2 S cm-1 among them. Furthermore, their electrochemical performance as cathode materials for ZIBs have been investigated. They all performed high reversible capacity, decent cycle stability and excellent rate capability. This work reveals the key insights into the electrochemical application potential of 2D c-MOFs and advances their development as cathode materials in ZIBs.
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In this paper, a facile hydrothermal pretreatment and molten salt activation route was presented for preparing a self-doped porous biochar (HMBC) from a nitrogenous biomass precursor of water hyacinth. With an ultrahigh specific surface area (2240 m2 g-1), well-developed hierarchical porous structure, created internal structural defects and doped surface functionalities, HMBC exhibited an excellent adsorption performance and catalytic activity for phenol removal via peroxydisulfate (PDS) activation. Specifically, the porous structure promoted the adsorption of PDS on HMBC, forming a highly active HMBC/PDS* complex and thereby increasing the oxidation potential of the system. Meanwhile, the carbon defective structure, graphitic N and CO groups enhanced the electron transfer process, favoring the HMBC/PDS system to catalyze phenol oxidation via an electron transfer dominated pathway. Thus, the system degraded phenol effectively with an ultralow activation energy of 4.9 kJ mol-1 and a remarkable oxidant utilization efficiency of 8.2 mol mol-oxidant-1 h-1 g-1. More importantly, the system exhibited excellent resistance to water quality and good adaptability for decontaminating different organic pollutants with satisfactory mineralization efficiency. This study offers valuable insights into the rational designing of a low-cost biochar catalyst for efficient PDS activation towards organic wastewater remediation.
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Carvão Vegetal , Eichhornia , Elétrons , Porosidade , Fenol , OxidantesRESUMO
PURPOSE: A consensus has not been reached on the value of quality of life (QoL) as a prognostic factor for survival in gastrointestinal cancer. This meta-analysis aimed to investigate the association between functioning scales of the EORTC QoL Questionnaire Core 30 (QLQ-C30) and the overall survival (OS) in patients with gastrointestinal cancer. METHODS: A systematic literature search was conducted in PubMed, Web of Science, and Embase databases, until February 7, 2023. The studies included were those that investigated the association between baseline QoL measured by the functioning scales of EORTC QLQ-C30 and OS in patients with gastrointestinal cancer. The prognostic capacity of QoL was calculated by pooling the adjusted hazard ratios (HR) with 95% confidence intervals (CI). RESULTS: Twenty-four studies' analyses reported by 22 eligible articles involving 11,609 patients were included. When compared with good parameters of QoL, poor global QoL (HR 1.81; 95% CI 1.53-2.13), physical functioning (HR 1.51; 95% CI 1.31-1.74), social functioning (HR 1.67; 95% CI 1.30-2.15), and role functioning scale (HR 1.42; 95% CI 1.20-1.29) were significantly associated with decreased OS. For each 10-point increase in QLQ-C30 parameters, the pooled HR of OS was 0.87 (95% CI 0.83-0.92) for global QoL, 0.87 (95% CI 0.83-0.92) for physical functioning, and 0.93 (95% CI 0.88-0.97) for role functioning. However, each 10-point increase in social, emotional, or cognitive functioning scale did not significantly predict OS. CONCLUSIONS: Baseline health-related QoL defined by the physical functioning or global QoL scale of EORTC QLQ-C30 significantly predicts OS in patients with gastrointestinal cancer.
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Neoplasias Gastrointestinais , Qualidade de Vida , Humanos , Neoplasias Gastrointestinais/psicologia , Neoplasias Gastrointestinais/mortalidade , Qualidade de Vida/psicologia , Inquéritos e Questionários , Prognóstico , Análise de SobrevidaRESUMO
The research of liver metastasis is a developing field. The ability of tumor cells to invade the liver depends on the complicated interactions between metastatic cells and local subpopulations in the liver (including Kupffer cells, hepatic stellate cells, liver sinusoidal endothelial cells, and immune-related cells). These interactions are mainly mediated by intercellular adhesion and the release of cytokines. Cell populations in the liver microenvironment can play a dual role in the progression of liver metastasis through different mechanisms. At the same time, we can see the participation of liver parenchymal cells and nonparenchymal cells in the process of liver metastasis of different tumors. Therefore, the purpose of this article is to summarize the relationship between cellular components of liver microenvironment and metastasis and emphasize the importance of different cells in the occurrence or potential regression of liver metastasis.
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Células Endoteliais , Neoplasias Hepáticas , Humanos , Células Endoteliais/patologia , Fígado/patologia , Neoplasias Hepáticas/patologia , Células de Kupffer , Hepatócitos , Microambiente TumoralRESUMO
Patients with chronic pelvic inflammation (CPI) experience irregular menstrual, ectopic pregnancy, and infertility. Yiyi Baijiang Decoction attenuates CPI in patients with uncovered mechanisms. CPI therapeutic targets intersected with those of Yiyi Baijiang Decoction, followed by importing into STRING to obtain protein-target interaction. "Drug-component-disease-target" interaction was constructed by Cytoscape. mRNA and protein levels were detected by real-time quantitative PCR (RT-qPCR) and western blot. Yiyi Baijiang Decoction contained 199 active ingredients. There were 1071 drug targets for Yiyi Baijiang Decoction and 1622 therapeutic targets for CPI. The GO functional enrichment analysis revealed 3445 biological processes, and the KEGG pathway enrichment analysis screened 67 signal pathways. Decreased ALB, increased protein kinase B (AKT1), interleukin (IL)-6, vascular endothelial growth factor A (VEGFA), and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K/AKT)-extracellular-regulated protein kinases (ERK)1/2 activation in CPI mice were abolished by Yiyi Baijiang Decoction. Yiyi Baijiang Decoction attenuates CPI by inactivating PI3K/AKT and ERK1/2 and regulating ALB, VEGFA, AKT1, and IL-6.
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Geriatric Nutritional Risk Index (GNRI) has been used as a predictor of adverse prognosis in patients with colorectal cancer (CRC). This meta-analysis sought to evaluate the prognostic role of GNRI in CRC patients. Two authors comprehensively searched the studies indexed in PubMed and Embase databases until March 15, 2022. Only observational studies evaluating the association between GNRI and adverse outcomes in patients with CRC were eligible. The prognostic value of GNRI was expressed by pooling the adjusted hazard ratio (HR) with 95% confidence intervals (CI) for the low vs. high GNRI group. Eight retrospective studies enrolling 3239 CRC patients were included. When comparing the low with the high GNRI group, the pooled HR was 2.40 (95% CI 1.71-3.39) for overall survival, 1.63 (95% CI 1.35-1.96) for disease-free survival, and 1.85 (95% CI 1.21-1.83) for ≥ 2 Clavien-Dindo Grade postoperative complications, respectively. Moreover, malnutrition defined by the cutoff GNRI at 98 was associated with a reduced overall survival (HR 1.66; 95% CI 1.37-2.02). Low GNRI score may be a promising predictor of postoperative complications and long-term poor survival in Asian patients with CRC. Malnutrition defined by the GNRI can be applied to improve risk stratification of CRC.
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Neoplasias Colorretais , Desnutrição , Humanos , Idoso , Avaliação Nutricional , Estado Nutricional , Avaliação Geriátrica , Estudos Retrospectivos , Fatores de Risco , Desnutrição/complicações , Prognóstico , Complicações Pós-Operatórias , Neoplasias Colorretais/complicaçõesRESUMO
This paper introduces an enclosed microfluidic chip that integrates sample preparation and the chamber-based digital polymerase chain reaction (cdPCR). The sample preparation of the chip includes nucleic acid extraction and purification based on magnetic beads, which adsorb nucleic acids by moving around the reaction chambers to complete the reactions including lysis, washing, and elution. The cdPCR area of the chip consists of tens of thousands of regularly arranged microchambers. After the sample preparation processes are completed, the purified nucleic acid can be directly introduced into the microchambers for amplification and detection on the chip. The nucleic acid extraction performance and digital quantification performance of the system were examined using synthetic SARS-CoV-2 plasmid templates at concentrations ranging from 101-105 copies per µL. Further on, a simulated clinical sample was used to test the system, and the integrated chip was able to accurately detect SARS-CoV-2 virus particle samples doped with interference (saliva) with a detection limit of 10 copies per µL. This integrated system could provide a promising tool for point-of-care testing of pathogenic infections.
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Microfluídica , Microfluídica/métodos , Reação em Cadeia da Polimerase , Ácidos Nucleicos/análise , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificaçãoRESUMO
Crystalline organic metal chalcogenides (OMCs) are a class of organic-inorganic hybrid semiconducting materials with continuous M-X (X = S, Se, Te) networks formed by the combination of metal nodes and chalcogen atoms from the organic ligands, which display great potentials in the fields of optoelectronics, catalysis, sensing, as well as energy conversion and storage. Here, we synthesized a wave-like 2D OMC material, [(AgBF4)2Me6BHS]n (Ag-BHSMe), from AgBF4 and 1,2,3,4,5,6-hexa(methylselanyl)benzene (Me6BHS) through a simple homogeneous reaction. In the solid state, Ag-BHSMe exhibits both fluorescence emission at room temperature and phosphorescent emission at 77 K. TEM, SEM, and confocal microscopy revealed that it is an intrinsic blue luminescent microcrystalline material. In addition, we found that it exhibited a highly selective fluorescence enhancement response to Pb2+ in an aqueous solution in the range of 10-4 to 10-2 mol L-1, which demonstrates its potential as a turn-on probe for the detection of lead ions.
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The PEBP gene family is crucial for the growth and development of plants, the transition between vegetative and reproductive growth, the response to light, the production of florigen, and the reaction to several abiotic stressors. The PEBP gene family has been found in numerous species, but the SLPEBP gene family has not yet received a thorough bioinformatics investigation, and the members of this gene family are currently unknown. In this study, bioinformatics was used to identify 12 members of the SLPEBP gene family in tomato and localize them on the chromosomes. The physicochemical characteristics of the proteins encoded by members of the SLPEBP gene family were also examined, along with their intraspecific collinearity, gene structure, conserved motifs, and cis-acting elements. In parallel, a phylogenetic tree was built and the collinear relationships of the PEBP gene family among tomato, potato, pepper, and Arabidopsis were examined. The expression of 12 genes in different tissues and organs of tomato was analyzed using transcriptomic data. It was also hypothesized that SLPEBP3, SLPEBP5, SLPEBP6, SLPEBP8, SLPEBP9, and SLPEBP10 might be related to tomato flowering and that SLPEBP2, SLPEBP3, SLPEBP7, and SLPEBP11 might be related to ovary development based on the tissue-specific expression analysis of SLPEBP gene family members at five different stages during flower bud formation to fruit set. This article's goal is to offer suggestions and research directions for further study of tomato PEBP gene family members.
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Solanum lycopersicum , Solanum lycopersicum/genética , Filogenia , Genoma de Planta , Família Multigênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Although asymmetric supercapacitors (ASCs) can achieve high energy density, the lifespan and power density are severely suppressed due to the low conductivity of using pseudocapacitive or battery-type electrode materials. Recently, nonporous conductive coordination polymers (c-CPs) have sparked interests in supercapacitors. However, their performance is expected to be limited by the nonporous features, low specific surface area and absence of ion-diffusion channels. Here, it is demonstrated that the capacity of nonporous CPs will be significantly enhanced by maximizing the number of faradaic redox sites in their structures through a comparative investigation on three highly conductive nonporous c-CPs, Cux BHT(x = 3, 4, 5.5). They show excellent capacitance of 312.1 F g-1 (374.5 C g-1 ) (Cu3 BHT), 186.7 F g-1 (224.0 C g-1 ) (Cu4 BHT) and 89.2 F g-1 (107.0 C g-1 ) (Cu5.5 BHT) at 0.5 A g-1 in a sequence related to the number of electron storage units in structures and outstanding rate performance and cycle stability. Furthermore, the constructed Cu3 BHT//MnO2 ASC device exhibits capacity retention of 92% (after 1500 cycles at 3 A g-1 ) and delivers a high energy density of 39.1 Wh kg-1 at power density of 549.6 W kg-1 within a large working potential window of 0-2.2 V.
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BACKGROUND: Adjuvant chemotherapy (CT) and chemoradiotherapy (CRT) after surgery are necessary to reduce the risk of metastasis and recurrence for resectable gastric cancer (GC) patients. Adjuvant CT and CRT have been proven to significantly improve the prognosis for GC patients, when compared with surgery only. However, it is still unclear whether radiotherapy offers additional survival benefits to advanced gastric cancer (AGC) patients. METHODS: PubMed, Cochrane Library, and Embase databases were systematically searched for eligible studies that compared survival benefits between CRT and CT. The endpoints of this meta-analysis were measured as HR for OS or DFS and 95% CI using fixed- or random-effect models. Additionally, side effects, completed rate, and metastatic risk, were calculated as OR. Subgroup analyses according to clinicopathological factors were presented. RESULTS: A total of 28 eligible studies involving 20,220 patients were included in our study. Of these, 17 studies evaluated the survival benefits of additional radiotherapy on overall survival (OS) of gastric cancer patients, ten reported the impact of CRT on disease-free survival (DFS), and 26 studies showed long-term survival rate. The pooled results were significant (HR for OS 0.84, 95% CI 0.71-0.99; HR for DFS 0.76, 95% CI 0.66-0.89). The subgroup analysis showed that adjuvant CRT increased OS for patients without preoperative treatment; showed similar nausea/vomiting, but an increased risk of neutropenia; reduced the risk of locoregional recurrence; failed to improve OS for lymph node (LN)-positive GC patients; and significantly improved prognosis for R1-treated patients. Of note, DFS was improved in all the subgroups via decreasing the locoregional recurrence. CONCLUSION: Compared with CT, adjuvant CRT can improve survival for advanced gastric cancer patients, with similar nausea/vomiting, but increased risk of neutropenia. Patients without preoperative treatment or with positive surgical margins should be strongly recommended to undergo CRT. Treatment regimens should be carefully decided by doctors based on patients' tolerance, physical status, and reaction to treatment. Moreover, CRT improves the DFS for patients regardless of subgroups, because it significantly reduced the risk of locoregional recurrence.
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Neutropenia , Neoplasias Gástricas , Quimiorradioterapia , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Intervalo Livre de Doença , Humanos , Náusea , Recidiva Local de Neoplasia/terapia , Neoplasias Gástricas/cirurgia , VômitoRESUMO
Construction of conductive coordination polymers (CPs) has already become an attractive strategy for the development of organic-inorganic hybrid functional materials with specific electrical performance, due to the great diversity and tunability of the chemical structures, electronic structures, as well as the functions they can offer. Here, we demonstrate a novel highly conductive CP based on silver (I) and benzenehexathiol (BHT), (Ag3BHT)n, which displays a different chemical stoichiometry and structural topology compared to the previously reported (Ag5BHT)n. Detailed structural analysis shows that this is caused by the unintentional oxidation of the ligand molecules during the CP formation process. (Ag3BHT)n displays an electrical conductivity of 39 S cm-1 at room temperature. Ultraviolet photoelectron spectroscopy characterization and density functional theory calculation reveal that its highly conducting behavior comes from the highly doped character of (Ag3BHT)n. In addition, band structure calculation proposed an unusual double Dirac cone. This work emphasizes the importance of the ligand oxidation strategy, which can greatly enrich the family of conductive CPs based on BHT and other noninnocent ligands.
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Due to the diversity of sulfur valence in cobalt-based sulfides, it is difficult to control the crystal phase and composition of the products during synthesis. Herein, a one-pot hydrothermal method is reported to self-assemble the cobalt sulfides (CoS2, Co9S8and Co3S4) with hollow nanostructures. The whole preparation process is simple and mild, avoiding high temperature calcination. The performances of the three kinds of cobalt sulfide in superior supercapacitors and electrocatalytic oxygen evolution performance applications follow the order of CoS2 > Co9S8 > Co3S4. Further analysis demonstrates that the performance difference in these cobalt sulfides may be attributed to three factors: the presence ofS22-,the coordination environment of Co and the presence of continuous network of Co-Co bonds. The distinctive electrochemical performance of CoS2and Co9S8may help us to better understand the excellent electrochemical activity of metal polysulfides and metal sulfides after doping or alloying. Therefore, this work may provide a reference in understanding and designing the electrode materials for highly efficient applications in the fields of energy storage and conversion.
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BACKGROUND: The number of positive lymph nodes, which was defined as "N stage", is mostly used to predict the survival of D2-resected gastric cancer patients, not the location. A "central lymph node" (CnLN) was defined by Ikoma et al., included common hepatic, celiac and proximal splenic artery LNs. CnLNs located in the extraperigastric area are included in the D2 LN station for gastric cancer. We speculate that CnLNs can be regarded as a predictor of survival. METHODS: Eligible advanced gastric cancer patients who underwent curative resection and D2 lymph node dissection between 2004 and 2012 at our institution were identified. The frequency of CnLN metastases and risk factors affecting DFS were examined. Survival differences were assessed by log-rank tests and Kaplan-Meier curves. RESULTS: The study identified 1178 patients who underwent curative surgery or D2 or more extensive lymphadenectomy. A total of 342 patients had been proven to have CnLN metastasis. Larger tumor size (P < 0.001), more frequent lymphatic vessel invasion (P < 0.001), signet ring cell histology (P = 0.014), and more advanced pathological T stage (P = 0.013) were significantly related to CnLNs metastasis. The patients with CnLN metastasis had a poor prognosis (HR for DFS of 1.366, 95%CI = 1.138-1.640, P = 0.001). For the pN2/3 patients, CnLN metastasis was associated with shorter 5-year DFS (for pN2 patients: 25.9% vs 39.3%, P = 0.017; for pN3 patients: 11.5% vs 23.4%, P = 0.005). CONCLUSION: Gastric cancer patients with CnLN metastasis who underwent D2 resection had a poor prognosis. With the same N stage, the patients with positive CnLNs had shorter survival. CnLNs metastasis could be a supplement to N stage and a predictor of survival in gastric cancer patients. Large sample, multicenter, randomized clinical trials are still needed in the future.
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Neoplasias Gástricas , Gastrectomia , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgiaRESUMO
In recent years, the abuse of antibiotics has led to the pollution of soil and water environment, not only poultry husbandry and food manufacturing will be influenced to different degree, but also the human body will produce antibody. The detection of antibiotic content in production and life is imperative. In this review, we provide comprehensive information about chemical sensors and biosensors for antibiotic detection. We classify the currently reported antibiotic detection technologies into chromatography, mass spectrometry, capillary electrophoresis, optical detection, and electrochemistry, introduce some representative examples for each technology, and conclude the advantages and limitations. In particular, the optical and electrochemical methods based on nanomaterials are discussed and evaluated in detail. In addition, the latest research in the detection of antibiotics by photosensitive materials is discussed. Finally, we summarize the pros and cons of various antibiotic detection methods and present a discussion and outlook on the expansion of cross-scientific areas. The synthesis and application of optoelectronic nanomaterials and aptamer screening are discussed and prospected, and the future trends and potential impact of biosensors in antibiotic detection are outlined.Graphical abstract.
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Antibacterianos/análise , Técnicas de Química Analítica/métodos , Contaminação de Alimentos/análise , Nanoestruturas/química , Poluentes Químicos da Água/análise , Animais , Humanos , CoelhosRESUMO
The solvent-free organic π-liquids have been attracting increasing attentions owing to the inherent optoelectronic properties accompanied by the advantages of non-volatility and high processability. Herein, we reported a series of naphthalene derivatives substituted with chiral branched alkyl chains, which are present as liquids (Nap1-3) or solid (Nap4) at room temperature, depending on the substitution positions. Circular dichroism (CD) and circularly polarized luminescence (CPL) were only observed for enantiomeric Nap2 (2,3-substituted) liquid. It is suggested that the chiral aggregation in the π-liquid leads to the CD signal and the chiral excimer resulting in the CPL performance. When achiral anthracene or pyrene was dissolved in Nap2, the π-liquid could serve as chirality and energy transfer media in which both CD and CPL emerged from the achiral anthracene. A CPL dissymmetry factor (|glum |) of anthracene reached to 5.2×10-2 when dissolved in chiral Nap2 liquid, which is nearly two orders of magnitude higher than that of the pure Nap2 π-liquid.
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Metal-bis(dithiolene) is one of the most promising structures showing redox activity, excellent electron transport and magnetic properties as well as catalytic activities. Perthiolated coronene (PTC), an emerging highly symmetric ligand containing the smallest graphene nanoplate was employed to manufacture a hybrid material with fused metal-bis(dithiolene) and graphene nanoplate, and it has been demonstrated as an efficient strategy for the construction of multifunctional materials recently. Herein, Co-PTC, a 2D MOF containing Co-bis(dithiolene) and coronene units is prepared via a homogeneous reaction for the first time as powder samples, which are bar-shaped microparticles composed of nanosheets. A neutral formula of [Co3 (C24 S12 )]n is verified for Co-PTC. Co-PTC plays an ultrahigh conductivity of approximately 45â S cm-1 at room temperature as compressed samples, which is among the highest value ever reported for the compressed powder samples of conducting MOFs. Moreover, Co-PTC exhibits good electrocatalytic performance in the hydrogen evolution reaction (HER) with a Tafel slope of 189â mV decade-1 and an operating overpotential of 227â mV at 10â mA cm-1 with pH=0, as well as a remarkable stability in the extremely acidic aqueous solutions, which is the best hydrogen evolution properties among metal-organic compounds.
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Four conjugated polymers are synthesized through indacenodithiohene (IDT) unit copolymerized with thiophene and thiophene derivatives. Indacenodithiohene-co-thieno[3,2-b]thiophene (IDT-TT) and indacenodithiohene-co-trans-1,2-di(2-thienyl)ethylene (IDT-TVT) exhibit better charge transport mobilities than indacenodithiohene-co-thiophene (IDT-T) and indacenodithiohene-co-3,4-ethoxylene dioxythiophene (IDT-EDOT), and also display superior thermoelectric properties after doping. Theoretical calculations suggest that IDT-EDOT and IDT-TVT have better coplanarities; the inferior performance for IDT-EDOT might be due to its low molecular weight. Meanwhile, it is worth mentioning that via the synergistic effect of two dopants (CN6CP, CuTFSI), the electrical conductivities of the polymers are further improved. The XPS data shows that the coordination interaction between copper ion and the cyano groups of CN6CP introduces cupric ions into the polymer films, which leads to the increase of the doping ratio.
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Polímeros/química , Tiofenos/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Cobre/química , Cianetos/química , Condutividade Elétrica , Polimerização , Teoria QuânticaRESUMO
3D well-crystallized metal-organic frameworks (MOFs), M-THBQ (M=Fe, Co, Mn, THBQ=tetrahydroxybenzoquinone), are synthesized and characterized. Their structures are determined as cubic cell in the group of Pm 3 â¾ from powder X-ray diffraction data, and their properties of electronic, magnetic and spectroscopic are also investigated. They are all semiconductors, and Fe-THBQ exhibits the air-stable n-type thermoelectric characteristic as its Seebeck coefficient reaches -130â µV K-1 , and the electrical conductivity is 2.7×10-4 â S cm-1 at 300â K. Additional, M-THBQ are paramagnetic, and the value of Weiss constant of Fe-THBQ is -219.37â K, indicating the existence of robust intramolecular antiferromagnetic exchanges. Meanwhile, they display strong absorption bands in the range of 220 to 1000â nm, suggest M-THBQ could have the potential to become photoabsorbers, and Fe-THBQ exhibits a narrow band gap of 0.63â eV according to the ultraviolet absorption edge spectrum.
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Conductive coordination polymers (CPs) have potential in a wide range of applications because of their inherent structural and functional diversity. Three electrically conductive CPs (Cux C6 S6 , x=3, 4 or 5.5) derived from the same organic linker (benzenehexathiol) and metal node (copper(I)) were synthesized and studied. Cux C6 S6 materials are organic-inorganic hybrid copper sulfides comprising a π-π stacking structure and cooper sulfur networks. Charge-transport pathways within the network facilitate conductivity and offer control of the Fermi level through modulation of the oxidation level of the non-innocent redox-active ligand. Two Cux C6 S6 (x=4 or 5.5) CPs display high electrical conductivity and they feature a tunable structural topology and electronic structure. Cu4 C6 S6 and Cu5.5 C6 S6 act as degenerate semiconductors. Moreover, Cu5.5 C6 S6 is a p-type thermoelectric material with a ZT value of 0.12 at 390â K, which is a record-breaking performance for p-type CPs.