排序方式: 共有69条查询结果,搜索用时 140 毫秒
61.
Hedi Wei Yi‐Hsiang Chao Chong Kang Cuihong Li Heng Lu Xue Gong Huanli Dong Wenping Hu Chain‐Shu Hsu Zhishan Bo 《Macromolecular rapid communications》2015,36(1):84-89
High‐molecular‐weight conjugated polymer HD‐PDFC‐DTBT with N‐(2‐hexyldecyl)‐3,6‐difluorocarbazole as the donor unit, 5,6‐bis(octyloxy)benzothiadiazole as the acceptor unit, and thiophene as the spacer is synthesized by Suzuki polycondensation. HD‐PDFC‐DTBT shows a large bandgap of 1.96 eV and a high hole mobility of 0.16 cm2 V−1 s−1. HD‐PDFC‐DTBT:PC71BM‐based inverted polymer solar cells (PSCs) give a power conversion efficiency (PCE) of 7.39% with a Voc of 0.93 V, a Jsc of 14.11 mA cm−2, and an FF of 0.56.
62.
Mariem Itaimi Dammak Zeineb Mzoughi Ibtissem Chakroun Hedi Ben Mansour Didier Le Cerf 《Natural product research》2020,34(10):1470-1474
AbstractIn this study, Box-Behnken Design was used to optimize the ultrasonic extraction of polysaccharides from quince peels (QPPs) by ascorbic acid and the effect of extraction temperature, extraction time and pH was evaluated. Under optimized conditions of temperature 90?°C, 60?min sonication time and pH?=?3.26, the extraction yield, the galacturonic acid yield and the concentration of sample required to scavenge 50% of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTS) values of QPPs were respectively 10.25%, 3.86% and 1.35?mg/mL. The QPPs extracted under optimum conditions was characterized by Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (1?H NMR) and Size exclusion chromatography (SEC/MALS/VD/DRI). The monosaccharide analysis revealed that arabinose was the most abundant, followed by galactose, glucose, mannose and xylose. Moreover, QPPs showed significant antioxidant activities (2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric- reducing antioxidant power (FRAP)) and reduced viability of human Caco-2 and murine B-16 cell lines in a dose-dependent manner. Hence QPPs could be used as antitumor agent in functional foods andpharmaceutical industries. 相似文献
63.
Vincenzo Lo Turco Hedi Ben Mansour Giacomo Dugo Giuseppa Di Bella 《Natural product research》2020,34(1):87-92
AbstractThis research is carried out in order to characterize the actual contamination by two ubiquitous environmental pollutants, plasticizers and Bisphenol A, in spices (black pepper, caraway and coriander) and aromatic herbs (fennel, laurel, mint, oregano, rosemary, thyme and verbena) from Algeria (n?=?26), Tunisia (n?=?65) and Italy (n?=?53). Algerian samples seem to contain fewer residues than Italian and Tunisian samples. Among the Italian samples, only aromatic herbs, precisely mint, oregano, and laurel, were contaminated. In general, all Tunisian samples showed five plasticizers residues: the caraway, among the spices, and the rosemary, among the aromatic herbs, are found to contain more residues. Also, dietary intake of these contaminants by spices and aromatic herbs under analysis seems not to constitute a risk to the consumers. 相似文献
64.
A macroscopic model is presented aimed at assessing the macroscopic elastic behaviour of materials reinforced by periodically distributed flexible membranes. According to this model, called multiphase model, the reinforced material is described not as a single homogenized continuum as in the classical homogenization approach, but as the superposition of two mutually interacting continuous media, namely the matrix phase and the reinforcement phase. It is shown in particular how such a model allows to capture both scale and boundary effects, which cannot be accounted for in a classical homogenization procedure. 相似文献
65.
Wenzel M Bertrand B Eymin MJ Comte V Harvey JA Richard P Groessl M Zava O Amrouche H Harvey PD Le Gendre P Picquet M Casini A 《Inorganic chemistry》2011,50(19):9472-9480
An unprecedented series of titanocene-gold bi- and trimetallic complexes of the general formula [[(η(5)-C(5)H(5))(μ-η(5):κ(1)-C(5)H(4)(CH(2))(n)PPh(2))TiCl(2)](m)AuCl(x)](q+) (n = 0, 2, or 4; m = 1, x = 1, q = 0 or m = 2, x = 0, q = 1) have been prepared and characterized spectroscopically. The luminescence spectroscopy and photophysics of one of the compounds, [[(η(5)-C(5)H(5))(μ-η(5):κ(1)-C(5)H(4)PPh(2))TiCl(2)](2)Au]PF(6), have been investigated in 2MeTHF solution and in the solid state at 77 and 298 K. Evidence for interfragment interactions based on the comparison of electronic band positions and emission lifetimes, namely, triplet energy transfer (ET) from the Au- to the Ti-containing chromophores, is provided. The cytotoxicity of the complexes was evaluated on A2780 ovarian cancer cells and on their cisplatin-resistant cell line A2780cisR; the compounds showed activity in the low micromolar range that was markedly more active than the corresponding titanocene-phosphine precursors [(η(5)-C(5)H(5))(η(5)-C(5)H(4)(CH(2))(n)PPh(2))TiCl(2)], cisplatin, and, for some of them, the gold analogue [(PPh(3))AuCl]. In an attempt to draw preliminary structure-activity relationships, cell uptake measurements and interaction studies with plasmid DNA and the model protein ubiquitin (Ub) have been undertaken on some of the compounds. 相似文献
66.
We have developed a new set of multifunctional multidentate OligoPEG ligands, each containing a central oligomer on which were laterally grafted several short poly(ethylene glycol) (PEG) moieties appended with either thioctic acid (TA) or terminally reactive groups. Reduction of the TAs (e.g., in the presence of NaBH(4)) provides dihydrolipoic acid (DHLA)-appended oligomers. Here the insertion of PEG segments in the ligand structure promotes water solubility and reduces nonspecific interactions, while TA and DHLA groups provide multidentate anchoring onto Au nanoparticles (AuNPs) and ZnS-overcoated semiconductor quantum dots (QDs), respectively. The synthetic route involves simple coupling chemistry using N,N-dicylohexylcarbodiimide (DCC). Water-soluble QDs and AuNPs capped with these ligands were prepared via cap exchange. As prepared, the nanocrystals dispersions were aggregation-free, homogeneous, and stable for extended periods of time over pH ranging from 2 to 14 and in the presence of excess electrolyte (2 M NaCl). The new OligoPEG ligands also allow easy integration of tunable functional and reactive groups within their structures (e.g., azide or amine), which imparts surface functionalities to the nanocrystals and opens up the possibility of bioconjugation with specific biological molecules. The improved colloidal stability combined with reactivity offer the possibility of using the nanocrystals as biological probes in an array of complex and biologically relevant media. 相似文献
67.
Hedi Zhao Miao Qi Yuan Gong Han Chen Dan Wang Jing Fan Yanmin Wang Jingjuan Wang 《Journal of separation science》2023,46(6):2200794
Danggui Buxue Decoction is a classic formula containing Astragali Radix and Angelicae Sinensis Radix in a 5:1 ratio and has been extensively used to treat blood deficiency for thousands of years. The aim of the study was to investigate the differences in plasma protein binding, pharmacokinetics, and tissue distribution of Danggui Buxue Decoction in normal and blood-deficient rats by ultra-performance liquid chromatography-tandem mass spectrometry. The effects on peripheral blood routine were verified. The compounds exhibited higher plasma protein binding and absorption in the model group compared to the control group, except formononetin. The six ingredients were distributed widely, and the highest concentrations were detected in the heart and uterus. As has been demonstrated in the previous study of the effect of Danggui Buxue Decoction, its potential is to serve as an effective traditional Chinese medicine formula for treating cardiovascular diseases and impacting estrogenic properties, which reveals the potential target organs of Danggui Buxue Decoction the heart and uterus. Our findings suggested that the absorption and distribution of different components in Danggui Buxue Decoction varies depending on the pathological state, molecular weight, lipid solubility, transporter-mediated efflux, and other factors. 相似文献
68.
Abderrahmen Abdelli Oumayma Bejaoui Hajer Bougatef Sarra Ouni Assaâd Sila Hedi M'rabet Xavier Moreau Mohamed Lotfi Efrit Damien Prim 《Journal of heterocyclic chemistry》2023,60(1):96-105
An efficient synthesis of new γ,δ-insaturated δ-lactam and glutarimide derivatives bearing a phosphonomethyl group from a common allylphosphonate precursor is described. Our approach is based on a two-step procedure involving the preparation of phosphonated-1,5-ketoester and −1,5-diester followed by an amidation–heterocyclization sequence. The first step proceeds via Michael's addition of ethyl acetoacetate and diethyl malonate on an allylphosphonate starting material. The second step consists of a base-promoted intramolecular amidation-cyclization sequence with primary amines, which accounts for the construction of δ-lactams and glutarimide skeletons. We performed the evaluation of angiotensin I-converting enzyme (ACE) inhibition using an in vitro enzyme assay on six new compounds. Five compounds showed potent ACE inhibitory activity, with IC50 values ranging from 0.02 to 0.27 mg/ml. Compared with Captopril, used as a reference drug, two new glutarimide derivatives exhibited higher efficiency ACE inhibition activity. 相似文献
69.
Yanmin Wang Yuan Gong Yao Xiao Yani Jiang Jianbo Chen Hedi Zhao Miao Qi Han Chen Jing Fan Jingjuan Wang 《Journal of separation science》2023,46(16):2200941
Danggui Buxue Decoction is a classic formula for replenishing qi and nourishing blood. Despite its widespread use, its dynamic metabolism involved remains unclear. Based on the sequential metabolism strategy, blood samples from different metabolic sites were obtained via in situ closed intestine ring integrated with a jugular venous continuous blood supply technique. An ultra-high-performance liquid chromatography-linear triple quadruple-Orbitrap-tandem mass spectrometry method was developed for the identification of prototypes and metabolites in rat plasma. The dynamic absorption and metabolic landscape of flavonoids, saponins, and phthalides were characterized. Flavonoids could be deglycosylated, deacetylated, demethylated, dehydroxylated, and glucuronicated in the gut and then absorbed for further metabolism. Jejunum is an important metabolic site for saponins biotransformation. Saponins that are substituted by Acetyl groups tend to lose their acetyl groups and convert to Astragaloside IV in the jejunum. Phthalides could be hydroxylated and glucuronidated in the gut and then absorbed for further metabolism. Seven components serve as crucial joints in the metabolic network and are potential candidates for the quality control of Danggui Buxue Decoction. The sequential metabolism strategy described in this study could be useful for characterizing the metabolic pathways of Chinese medicine and natural products in the digestive system. 相似文献