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101.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(7):508-516
In the structure of 2‐(4‐chloroanilino)‐1,3,2λ4‐diazaphosphol‐2‐one, C12H11ClN3OP, each molecule is connected with four neighbouring molecules through (N—H)2…O hydrogen bonds. These hydrogen bonds form a tubular arrangement along the [001] direction built from R 33(12) and R 43(14) hydrogen‐bond ring motifs, combined with a C (4) chain motif. The hole constructed in the tubular architecture includes a 12‐atom arrangement (three P, three N, three O and three H atoms) belonging to three adjacent molecules hydrogen bonded to each other. One of the N—H groups of the diazaphosphole ring, not co‐operating in classical hydrogen bonding, takes part in an N—H…π interaction. This interaction occurs within the tubular array and does not change the dimension of the hydrogen‐bond pattern. The energies of the N—H…O and N—H…π hydrogen bonds were studied by NBO (natural bond orbital) analysis, using the experimental hydrogen‐bonded cluster of molecules as the input file for the chemical calculations. In the 1H NMR experiment, the nitrogen‐bound proton of the diazaphosphole ring has a high value of 17.2 Hz for the 2J H–P coupling constant. 相似文献
102.
Nanomaterials with helical morphologies have attracted much attention owing to their potential applications as nanosprings, chirality sensors and in chiral optics. Single‐handed helical Ta2O5 nanotubes prepared through a supramolecular templating approach are described. The handedness is controlled by that of the organic self‐assemblies of chiral low‐molecular‐weight gelators (LMWGs). The chiral LMWGs self‐assemble into single‐handed twisted nanoribbons through H‐bonding, hydrophobic association, and π‐π stacking. The Ta2O5 nanotubes are formed by the adsorption and polycondensation of Ta2O5 oligomers on the surfaces and edges of the twisted organic nanoribbons followed by removal of the template. The optical activity of the nanotubes is proposed to originate from the chiral defects on the inner surfaces of the tubular structures. Single‐handed twisted LiTaO3 nanotubes can also be prepared using Ta2O5 nanotubes. 相似文献
103.
《Macromolecular bioscience》2017,17(6)
A fully starch‐derived bioactive 3D porous scaffold is developed. The bioactivity is introduced through nanosized graphene oxide (nGO) derived from starch by microwave‐assisted degradation to carbon spheres and further oxidation to GO nanodots. nGO is covalently attached to starch to prepare functionalized starch (SNGO) via an esterification reaction. nGO and SNGO exhibit no cytotoxicity to MG63 at least up to 1000 µg mL−1 under (3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay. Porous scaffolds consisting of starch and SNGO (S/SNGO) or nGO (S/nGO) are prepared by freeze drying. The porosity and water uptake ability of the scaffolds depend on the concentration of nGO. Moreover, nGO, as a bioactive nanofiller, functions as an effective anchoring site for inducing CaP recrystallization in simulated body fluid. Among all modified starch‐based scaffolds, the S/SNGO scaffold containing the highest concentration of covalently attached SNGO (50%) induces the largest amount of hydroxyapatite, a type of CaP crystal that is closest to bone. The prepared 3D porous nGO functionalized scaffold, thus, exhibits potential promise for bone/cartilage tissue engineering.
104.
《Journal of separation science》2017,40(16):3301-3310
Magnetic graphene oxide was modified by four imidazole‐based ionic liquids to synthesize materials for the extraction of polysaccharides by magnetic solid‐phase extraction. Fucoidan and laminarin were chosen as the representative polysaccharides owing to their excellent pharmaceutical value and availability. Fourier transform infrared spectroscopy, field‐emission scanning electron microscopy, and thermogravimetric analysis were applied to characterize the synthesized materials. Single‐factor experiments showed that the extraction efficiency of polysaccharides was affected by the amount of ionic liquids for modification, solid–liquid ratio of brown alga and ethanol, the stirring time of brown alga and ionic liquid‐modified magnetic graphene oxide materials, and amount of 1‐(3‐aminopropyl)imidazole chloride modified magnetic graphene oxide materials added to the brown alga sample solution. The results indicated that 1‐(3‐aminopropyl)imidazole chloride modified magnetic graphene oxide possessed better extraction ability than graphene oxide, magnetic graphene oxide, and other three ionic‐liquid‐modified magnetic graphene oxide materials. The highest extraction recoveries of fucoidan and laminarin extracted by 1‐(3‐aminopropyl)imidazole chloride modified magnetic graphene oxide were 93.3 and 87.2%, respectively. In addition, solid materials could be separated and reused easily owing to their magnetic properties. 相似文献
105.
《Macromolecular bioscience》2017,17(6)
African swine fever virus (ASFV) is one of the most dangerous viruses for pigs and is endemic in Africa but recently also spread into the Russian Federation and the Eastern border of the EU. So far there is no vaccine or antiviral drug available to curtail the infection. Thus, control strategies based on novel inhibitors are urgently needed. Another highly relevant virus infection in pigs is Aujeszky's disease caused by the alphaherpesvirus pseudorabies virus (PrV). This article reports the synthesis and biological evaluation of novel extracellular matrix‐inspired entry inhibitors based on polyglycerol sulfate‐functionalized graphene sheets. The developed 2D architectures bind enveloped viruses during the adhesion process and thereby exhibit strong inhibitory effects, which are equal or better than the common standards enrofloxacin and heparin as demonstrated for ASFV and PrV. Overall, the developed polyvalent 2D entry inhibitors are nontoxic and efficient nanoarchitectures, which interact with various types of enveloped viruses. Therefore they prevent viral adhesion to the host cell and especially target viruses that rely on a heparan sulfate‐dependent cell entry mechanism.
106.
《Angewandte Chemie (International ed. in English)》2017,56(33):9990-9993
The thermal reduction of N2O by CO mediated by the metal‐free cluster cations [Si2Ox].+ (x =2–5) has been examined in the gas phase using Fourier transform ion cyclotron resonance (FT‐ICR) mass spectrometry in conjunction with quantum chemical calculations. Three successive oxidation/reduction steps occur starting from [Si2O2].+ and N2O to form eventually [Si2O5].+; the latter as well as the intermediate oxide cluster ions react sequentially with CO molecules to regenerate [Si2O2].+. Thus, full catalytic cycles occur at ambient conditions in the gas phase. Mechanistic aspects of these sequential redox processes have been addressed to reveal the electronic origins of these unparalleled reactions. 相似文献
107.
Catalytic Performance of Graphite Oxide Supported Au Nanoparticles in Aerobic Oxidation of Benzyl Alcohol: Support Effect 下载免费PDF全文
Various Au/GO catalysts were prepared by depositing Au nanoparticles on thermally- and chemically-treated graphite oxide (GO) supports using a sol-immobilization method. The surface chemistry and structure of GO supports were characterized by a series of analytical techniques including X-ray photoelectron spectroscopy, temperature-programmed desorption and Raman spectroscopy. The results show that thermal and chemical treatments have large influence on the presence of surface oxygenated groups and the crystalline structure of GO supports. A strong support effect was observed on the catalytic activity of Au/GO catalysts in the liquid phase aerobic oxidation of benzyl alcohol. Compared to the amount and the type of surface oxygen functional groups, the ordered structure of GO supports may play a more important role in determining the catalytic performance of Au/GO catalysts. 相似文献
108.
Synthesis of Cu2O/Ag Composite with Visible Light Photocatalytic Degradation Activity for in situ SERS Analysis 下载免费PDF全文
A multifunctional Cu2O/Ag micro-nanocomposite, which has the characteristics of high catalytic activities under the visible light and high surface-enhanced Raman scattering (SERS) activity, was fabricated via a facile method and employed for the in situ SERS monitoring of the photocatalytic degradation reaction of crystal violet. Through the variation of the AgNO3 concentration, Ag content on the Cu2O template can be controllably tuned, which has great influence on the SERS effect. The results indicate that Ag nanoparticles form on the Cu2O nanoframes to obtain the Cu2O/Ag nanocomposite, which can act as an excellent bifunctional platform for in situ monitoring of photocatalytic degradation of organic pollutions by SERS. 相似文献
109.
利用化学沉淀法和溶胶凝胶法,通过两步法成功制备出含有尖晶石钴铁氧体和氧化铜的复合催化剂CoFe2O4/CuO,通过扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和X射线衍射(XRD)对制备出的CoFe2O4/CuO进行表征,探究不同高级氧化体系对磺胺甲恶唑(SMX)去除能力,考察过氧乙酸(PAA)浓度、催化剂投加量、水体中常见干扰物质(Cl-,HCO-3,SO42-,HA)和不同自由基捕获剂对SMX去除的影响。分析结果表明CoFe2O4/CuO同时具有CoFe2O4与CuO的特征,对比单独CoFe2O4与CuO,CoFe2O4/CuO对PAA展现出极高的活化性能,在最佳反应条件下(催化剂投加量=20mg·L-1,c(PAA)=200μ... 相似文献
110.
《Mendeleev Communications》2023,33(1):138-140
Vanadium diboride was directly synthesized by borothermal reduction of V2O5 with the addition of epoxy resin as a reducing agent for the low-temperature reduction of vanadium(V) to vanadium(IV), which leads to the gradual removal of oxygen by the formation of CO gas. The slow rate of gas release prevents destruction of green body, which usually occurs during conventional borothermal reduction. This makes it possible to directly obtain VB2 powder with an average particle size of 200–300 nm without need to prepare intermediate lower vanadium oxides. 相似文献