Materials
·
2020
·Vol. 13
·期 24
·5733
·
IF 3.057
Tiancheng He,Caihuan Lv,Wenhao Li,Guohua Huang,Zhihui Hu,Jianmei Xu
The electronics related to the fifth generation mobile communication technology (5G) are projected to possess significant market potential. High dielectric constant microwave ceramics used as filters and resonators in 5G have thus attracted great attention. The Ba6−3x(Sm1−yNdy)8+2xTi18O54(x =2/3) ceramic system has aroused people’s interest due to its underlying excellent microwave dielectric properties. In this paper, the relationships between the dielectric constant, Nd-doped content, sintering temperature and the density of Ba6−3x(Sm1−yNdy)8+2xTi18O54(x =2/3) ceramics were studied. The linear regression equation was established by statistical product and service solution (SPSS) data analysis software, and the factors affecting the dielectric constant have been analyzed by using the enter and stepwise methods, respectively. It is found that the model established by the stepwise method is practically significant withY= −71.168 + 6.946x1+ 25.799x3, whereY,x1andx3represent the dielectric constant, Nd content and the density, respectively. According to this model, the influence of density on the dielectric constant is greater than that of Nd doping concentration. We bring the linear regression analysis method into the research field of microwave dielectric ceramics, hoping to provide an instructive for the optimization of ceramic technology.Keywords:microwave dielectric ceramics;Ba6−3x(Sm1−yNdy)8+2xTi18O54(x =2/3) system;dielectric constant;linear regression analysis
研究领域:
材料科学
·
电子工程
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DOI
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2014
·
IF 3.816
Wang Liju,Keyume Ablajan,Feng Jun
A rapid and efficient ultrasound-promoted one-pot synthesis of spiro[indoline-3,4′-pyrano[2,3-c]pyrazole] derivatives is described here. The reaction of substituted phenylhydrazine and dialkyl acetylenedicarboxylate with substituted isatin and malononitrile is catalyzed by l -proline to give good-to-excellent yields in water/ethanol (v/v, 1:1) at room temperature.
研究领域:
有机化学
·
催化反应
✓ 已验证
DOI
PubMed
高影响因子
ORGANIC ELECTRONICS
·
2019
·
IF 3.495
Tongchao Chu,Xiuping Ju,Xiao Han,Hongmei Du,Yan Zhang,Jinsheng Zhao,Junhong Zhang
Three novel electrochromic copolymers PTPE-1, PTPE-2, and PTPE-3 were synthesized by changing the ratio of donor to acceptor using the Stille coupling polymerization . 5,8,14,17-tetrabromoquinoxaline[2′,3':9,10]phenanthro[4,5-abc] phenazine (monomer b) was first introduced and employed as multi-functionalized unit with bisquinoxaline structure and high planarity, which was used as the acceptor unit. Two electron-rich monomers ProDOT-decyl 2 (monomer a) and thiophene (monomer c) are selected as the co-monomers and donor units. The three polymers were tested by X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), spectro-electrochemistry, kinetics, thermogravimetric analysis (TG), etc. All three polymers have narrow band gaps of lower than 1.85 eV and satisfactory thermal stability. As to electrochromic switching properties, the polymers showed high optical contrast and fast response time both in the visible and near-infrared regions. The optical contrasts are 53.35% at 540 nm and 66.49% at 1325 nm for PTPE-3, and its coloration efficiencies are 163 cm 2 C −1 at 540 nm, 205 cm 2 C −1 at 1325 nm, with fast switch time of less than 1 s. The color changes of three polymers were diversified and distinct, PTPE-1 changes from chestnut color to blue-gray color, PTPE-2 changes from dull red color to wathet color and PTPE-3 changes from deep red color to light blue-gray color. The excellent properties of the polymers might result from their cross-linked structure and consequent formation of the compatible ion transport channel.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 24
·10873-10883
·
IF 2.7
Yunxia Shi,Hui Duan,Meiyan Du,Xia Kong,Ke Xue,Guang Lu,Qingyun Liu
In this work, 2(3),9(10),16(17),23(24)-octamethoxyphthalocyanine (Pc(OH)8) was first used to modify Cu/CuFe2O4(Cu/CFO) nanospheres, and Pc(OH)8–Cu/CFO nanocomposites with enhanced peroxidase mimetic enzyme activity was obtained compared to the performance of Cu/CFO alone. SEM, XRD, and XPS were used to study the surface morphology, phase composition and elemental analysis of the newly synthesized Pc(OH)8–Cu/CFO. Using TMB as the chromogenic substrate, Pc(OH)8–Cu/CFO accelerate the oxidation process of chromogenic substrate 3,3′,5,5′- tetramethylbenzidine (TMB) by hydrogen peroxide in three minutes. The catalytic oxidation mechanism of Pc(OH)8–Cu/CFO on TMB was comprehensively investigated through free radical and fluorescence probe experiments. Based on the excellent catalytic performance of the composite materials, a simple and fast colorimetric sensing platform for the colorimetric detection of H2O2 and glutathione (GSH) was constructed in the range of 0.6–5 mM and 2–10 μM with detection limits (LODs) of 0.35 mM and 0.55 μM, respectively. In addition, using Pc(OH)8–Cu/CFO colorimetric detection for GSH has a lower detection limit, good selectivity and high sensitivity, which is expected to become an ideal material for GSH colorimetric detection.
研究领域:
材料科学
·
纳米技术
·
分析化学
·
生物传感器
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2023
·Vol. 225
·期 5
·2300361
·
IF 2.5
Dan Liu,Hui Liang,Jiang Lu
A novel monomer, N -(2-((3-morpholine-3-isopropyl)thio)ethyl)methacrylamide (MTMA), is synthesized and polymerized by reversible addition-fragmentation chain transfer (RAFT) polymerization to give a thermoresponsive polymer poly[ N -(2-((3-morpholino-3-oxopropyl)thio)ethyl)methacrylamide] (PMTMA). PMTMA exhibits reversible thermoresponsive phase transitions of the lower critical solution temperature (LCST) type in water and the upper critical solution temperature (UCST) type in ethanol and methanol. The degree of polymerization and concentration of PMTMA, and solvent type have a significant influence on the transition temperature. PMTMA shows complicated thermoresponse in water–alcohol mixtures. In water–ethanol mixtures, the phase diagram of PMTMA can be divided into three regions according to ethanol volume percentages, φ : 0 ≤ φ < 15% for an LCST region; 15% ≤ φ < 91.5% for a complete dissolution region; 91.5% ≤ φ ≤ 100% for a UCST region. At high water content, the LCST increases with increasing ethanol content; and at high ethanol content, the UCST decreases with increasing water content. In water–methanol mixtures, PMTMA shows more complex thermoresponse. In the range of 0–50 °C, the phase diagram can be divided into five regions, depending on the methanol volume percentages φ : 0 ≤ φ < 15% for LCST region; 15% ≤ φ < 25% for immiscible region; 25% ≤ φ < 85% for UCST region; 85% ≤ φ < 95% for fully dissolved region; 95% ≤ φ ≤ 100% for another UCST region.
研究领域:
高分子化学
·
材料科学
·
物理化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Tiantian Wang,Jianhong Wei,Furong Shi,Hejie Wang,Jinye He,Xudong Lv,Yuan Zhou,Pengzhi Guo,Chenglong Wang,Yangjun Xia
In recent years, polymerized small molecule acceptors (PSMAs) have emerged as a promising strategy that combines the strong absorption of small molecules with the film-forming ability and stability of polymers, thereby greatly boosting the performance of all-polymer solar cells (all-PSCs). We designed a non-fused acceptor, DTBT-IC, and its polymeric counterpart, PDTBT-Br-T, by selecting DTBT as the core, bithiophene as the π-bridge, and IC as the terminal group. PDTBT-Br-T was synthesized via Stille coupling and used with PM6 as the donor to fabricate organic solar cells. The PDTBT-Br-T-based device delivered superior performance, with a VOC of 1.050 V, JSC of 9.32 mA cm−2, FF of 45.33%, and a PCE of 4.44%, outperforming the DTBT-IC-based counterpart. Morphological and structural analyses revealed that PDTBT-Br-T exhibits more ordered backbone stacking and defined phase separation, enhancing exciton dissociation and charge transport, and suppressing energy loss. The study highlights that polymerization of DTBT-IC enhances intermolecular packing and microstructure, offering critical design insights for efficient all-PSCs.
研究领域:
材料科学
·
高分子化学
·
有机电子学
·
光伏技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2018
·
IF 4.805
Zhen-Hua Li,Zhi-Jiang Jiang,Qiao-Ling Shao,Jin-Jing Qin,Qiang-Feng Shu,Wen-Hao Lu,Wei-Ke Su
A one-pot cascade heterocyclization strategy has been developed for the synthesis of 2,4-dichloro-substituted pyrano[2,3-d]pyrimidines and furo[2,3-d]pyrimidines from linear γ- and β-ketomalononitriles using triphosgene and triphenylphosphine oxide. The reaction afforded synthetic useful products with moderate to good yields, bypassing the conventional harsh conditions of chlorination. The mechanistic study revealed that the reaction proceeded with a non-isocyanate route, and the second step may conduct in a triphenylphosphine oxide-catalyzed manner.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
POLYMER TESTING
·
2021
·
IF 4.282
Haochuan Luo
An effective method to prepare crosslinked polybenzimidazole (PBI) via [2 + 3] Huisgen cycloadditions has been proposed. Propargyl modified PBI (PBI-PG) has been synthesized firstly. In the presence of diazido crosslinkers, PBI-PG can be thermally crosslinked by [2 + 3] Huisgen cycloadditions. Evidences from 1 H NMR and ATR spectra imply a small amount of grafting alkenyl structures on PBI-PG. The grafting alkenyl structures provide another crosslinking mechanism named as alkyne-alkene crosslink. The alkyne-alkene crosslink is highly efficient under heat to form crosslinking networks which display toughness, low tensile strengths, and large swelling ratios in phosphoric acid (PA) solutions. Influences of rigidities and chain lengths of crosslinkers on performances of crosslinked PBIs have been investigated. PBIs crosslinked by rigid crosslinkers behave as brittle materials while that crosslinked by flexible crosslinkers behave as tough materials. Addition of crosslinkers leads to decreased gel fractions but improved tensile strengths, which is attributed to competition results of crosslinking and plasticizing effects. PBI-R2-20, which is crosslinked by a long rigid crosslinker, exhibits the highest tensile strength of 102.33 MPa, which is 66.34 MPa higher than that of PBI-PG. With even lower PA uptakes, PBIs crosslinked by rigid crosslinkers display more thermally stable and higher conductivities than that crosslinked by flexible crosslinkers. After doping in 12 mol/L PA solution, PBI-R2-20, with an acid uptake of 163 wt%, displays the highest tensile strength of 8.1 MPa and the most thermally stable and the highest conductivity which reaches a maximum of 2.30 × 10 −2 S cm −1 at 188 °C among all crosslinked membranes.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
INSTRUMENTATION SCIENCE & TECHNOLOGY
·
2017
·
IF 0.874
Shuyan Niu,Yajie Fang,Kun Zhang,Juan Sun,Jun Wan
A facile and sensitive fluorescent strategy for the determination of dopamine is reported using 2, 3-diaminophenazine. Dopamine caused autooxidation in the presence of oxygen with catalysis by Mn2+ and formed 2, 3-dihydro-1H-indole-5,6-dione. 2, 3-Diaminophenazine provided relatively strong fluorescence. 2, 3-Diaminophenazine in aqueous solution caused fluorescence quenching when the aminochrome condensed with 2, 3-diaminophenazine to allow the determination of dopamine. Under the optimized conditions, the linear dynamic range for dopamine was from 2.0 × 10−6 mol · L−1 to 6.1 × 10−5 mol · L−1 with a detection limit of 1.76 × 10−6 mol · L−1.
研究领域:
分析化学
·
生物医学
✓ 已验证
产品关联
DOI
高影响因子
ACS Infectious Diseases
·
2025
·
IF 3.8
Feifei Zhao,Yizhen Zhu,Lingxiang Mao,Honghao Huang,Wei Wei,Qiangcheng Deng,Youzhi Tang,Ning Han,Zhenling Zeng
Staphylococcus aureus poses a global threat to livestock health and public health security, necessitating a novel antibiotic. Pleuromutilin, a natural antibiotic, has served as a promising foundation for developing new antibacterial agents through structural modification. This study aims to evaluate the antibacterial potential, safety, and pharmacokinetic profile of a novel pleuromutilin derivative 2-3 (22-[2-(L-prolylamino)phenylsulfanyl]-22-deoxypleuromutilin). The compound 2–3 exhibited potent antibacterial activity (MIC = 0.25 μg/mL), concentration-dependent bactericidal effects, and prolonged post-antibiotic effects (PAEs). Safety assessments revealed low cytotoxicity (CC50 = 62.63 μg/mL) and no observable hemolytic activity. In vitro metabolic studies indicated species-dependent clearance, primarily mediated by CYP3A4. Pharmacokinetic in rats showed rapid absorption and elimination, with oral and intramuscular bioavailability of 16.03% ± 8.82% and 53.36% ± 12.27%, respectively. Notably, 2–3 demonstrated superior efficacy over tiamulin in a neutropenic murine thigh infection model. Molecular docking revealed a stronger binding free energy between 2–3 and the 50S ribosomal subunit compared to tiamulin. Collectively, these results highlight 2–3 as a promising clinical candidate against S. aureus infections, characterized by enhanced efficacy and a favorable safety profile.
研究领域:
抗生素研发
·
药理学
·
微生物学
·
药物化学
·
药物代谢
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULAR CELL
·
2024
·
IF 14.5
Wei Luo,Yunyuan Xu,Jie Cao,Xiaoyu Guo,Jingdan Han,Yuanyuan Zhang,Yuda Niu,Meiling Zhang,Yi Wang,Guohua Liang,Qian Qian,Song Ge,Kang Chong
While it is known that temperature sensors trigger calcium (Ca 2+ ) signaling to confer cold tolerance in cells, less is known about sensors that couple with other secondary messengers. Here, we identify a cold sensor complex of CHILLING-TOLERANCE DIVERGENCE 6 (COLD6) and osmotin-like 1 (OSM1), which triggers 2′,3′-cyclic adenosine monophosphate (2′,3′-cAMP) production to enhance cold tolerance in rice. COLD6, which is encoded by a major quantitative trait locus (QTL) gene, interacts with the rice G protein α subunit (RGA1) at the plasma membrane under normal conditions. Upon exposure to chilling, cold-induced OSM1 binds to COLD6, kicking out RGA1 from interaction. This triggers an elevation of 2′,3′-cAMP levels for enhancing chilling tolerance. Genetic data show that COLD6 negatively regulates cold tolerance and functionally depends on OSM1 in chilling stress. COLD6 alleles were selected during rice domestication. Knockout and natural variation of COLD6 in hybrid rice enhanced chilling tolerance, hinting design potential for breeding. This highlighted a module triggering 2′,3′-cAMP to improve chilling tolerance in crops.
研究领域:
植物学
·
遗传学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW PHYTOLOGIST
·
2026
·
IF 8.7
Lele Chu,Xiangming Shang,Bachar Dahro,Xi Zeng,Wenqiang Hu,Chunlong Li,Ji-Hong Liu
Summary Ethylene exerts a divergent role in modulating plant organ abscission. Spermidine (Spd) shares a common precursor for de novo biosynthesis with ethylene, but the antagonistic role between them in the regulation of plant organ abscission remains largely elusive. Here, RNA-sequencing of abscission zones from ethylene-treated sweet orange ( Citrus sinensis L.) fruit led to the identification of two ethylene-responsive factors (ERFs), CsERF113 and CsERF7. CsERF113 functioned in promoting fruit abscission and suppressed Spd accumulation, whereas CsERF7 exhibited an opposite trend. CsERF113 and CsERF7 were verified to act as a transcriptional repressor or an activator of CsSAMDC1 / 2 / 3 encoding S -adenosylmethionine decarboxylase (SAMDC), an enzyme responsible for Spd biosynthesis, by binding directly to their promoters in an ethylene-dependent manner. Moreover, CsSAMDC1 / 2 / 3 functioned to inhibit fruit abscission by promoting Spd synthesis. Interestingly, CsERF7 and CsERF113 transcriptionally repressed each other to modulate the ethylene-mediated downregulation of CsSAMDC1 / 2 / 3 , forming an antagonistic regulatory circuit that could be negatively orchestrated by exogenous Spd. Taken together, our results uncover that CsERF113 and CsERF7 integrate the ethylene signal to antagonistically regulate CsSAMDC1 / 2 / 3 -mediated synthesis of Spd and fruit abscission. This study provides important insights into understanding the molecular mechanisms by which ethylene and Spd antagonize to modulate fruit abscission.
✓ 已验证
DOI
PubMed
高影响因子
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