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991.
Dr. Karol Strutyński Prof. Aurelio Mateo-Alonso Prof. Manuel Melle-Franco 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6569-6575
The key electronic properties of a family of 2D frameworks structurally convergent with holey graphenes were studied. The bandgap of these materials decreases monotonically with size, showing a common trend with anthracenes and kekulenes. This was rationalized by Clar's sextet rule, which reveals a direct relationship between the molecular systems and the 2D frameworks. In addition, a detailed benchmark against experimental data showcased the high quality of the models, which reproduce accurately available electronic properties. Overall, it was shown that DFT can be used to screen and understand the intrinsic bandgaps and electrochemistry potentials for technological applications prior to the synthesis of π-conjugated porous materials. 相似文献
992.
Density functional theory calculations are performed to probe reaction pathways of N2O reduction by CO molecule catalysed over Si-doped C3N (Si-C3N) nanosheets. According to our results, a single Si atom can be stabilised above the C- or N-vacancy site of C3N due to the formation of strong Si-N or Si-C covalent bonds. The reduction of N2O over Si-C3N is characterised as a two-step process. First, N2O is dissociated to N2 and an activated oxygen atom (Oads) without an energy barrier. Then, the Oads moiety is removed by CO molecule by overcoming negligible activation energy. 相似文献
993.
994.
Tong Guo Lina Wang Sen Sun Yan Wang Xiaoling Chen Kangning Zhang Dongxia Zhang Zhonghua Xue Xibin Zhou 《中国化学快报》2019,30(6):1253-1260
Layered MoS2@graphene functionalized with nitrogen-doped graphene quantum dots (MoS2@NGQDs-GR) was obtained by one-pot hydrothermal method, as an enhanced electrochemical hydrogen evolution catalyst. 相似文献
995.
Oxidative stress can transform immunologic disorders to malignancy by enhancing the effect of pathogenic factors associated with adverse health problems. Biomarkers generated during oxidative stress are essential in assessing the in vivo condition of the cell for evaluating health and diagnosing the disease at an early stage, prognosis, benign and effectual drug development, and testing the drug efficacy. 3-Nitro-L-tyrosine is an oxidative stress biomarker produced from L-tyrosine through nitration mediated by active metabolites. Thus, precise detection of 3-NO2-Tyr in the biological medium is significantly important to monitor the cell environment. Consequently, a novel electrochemical sensing platform had been designed using ZnNb2O6 nanostructures anchored f-CNF as a glassy carbon electrode modifier. The crystalline and structural features, morphology, and elemental composition of ZnNb2O6/f-CNF nanocomposite were keenly verified. The synchronic activation of ZnNb2O6/f-CNF nanocomposite for effective detection of 3-NO2-Tyr is mainly due to the synergic effect between its counterparts. Accordingly, the fabricated sensor possesses a remarkably low limit of detection (0.021 μM) with a good linear range, and sensitivity is noted to be 7.745 μA/μM?cm?2. The consistency of this sensor was evinced through real-time monitoring of 3-NO2-Tyr in urine and saliva samples which is beneficial in monitoring the pathological situation. 相似文献
996.
Dioxomolybdenum(VI) complex covalently attached to amino‐modified graphene oxide: heterogeneous catalyst for the epoxidation of alkenes
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Zhifang Li Shujie Wu Dafang Zheng Jiayin Liu Heng Liu Haiming Lu Qisheng Huo Jingqi Guan Qiubin Kan 《应用有机金属化学》2014,28(5):317-323
Transition metal salen complex MoO2–salen was successfully tethered onto amino‐functionalized graphene oxide (designated as MoO2–salen–GO), which was tested in the epoxidation of various alkenes using tert‐butylhydroperoxide or H2O2 as oxidant. Characterization results showed that dioxomolybdenum(VI) complex was successfully grafted onto the amino‐functionalized graphene oxide and the structure of the graphene oxide was well preserved after several stepwise synthesis procedures. Catalytic tests showed that heterogeneous catalyst MoO2–salen–GO was more active than its homogeneous analogue MoO2–salen in the epoxidation of cyclooctene due to site isolation. In addition, the MoO2–salen–GO catalyst could be reused three times without significant loss of activity. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
998.
Jemini Jose Athimotlu Raju Rajamani Sreekanth Anandaram Sujin P. Jose Sebastian C. Peter Sreeja P B 《应用有机金属化学》2019,33(9)
Covalently anchored chromium complex on reduced graphene oxide (rGO‐Cr) is successfully synthesised through trimethoxy silyl propanamine (TMSPA) and phenyl azo salicylaldehyde (PAS) coupling. The rGO‐Cr is characterised by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), electron dispersive analysis of X‐rays (EDAX), Raman spectroscopy, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). Absorption and emission properties of rGO‐TMSPA‐PAS are studied by excitation dependent photoluminescence emissions at room temperature. Electrochemical sensing activity of rGO‐Cr is monitored for paracetamol using modified glassy carbon electrode. Cyclic voltammetry measurements indicated that rGO‐Cr substantially enhance the eletrochemical response of paracetamol. The experimental factors are investigated and optimized. 相似文献
999.
A theranostic platform with integrated diagnostic and therapeutic functions as well as specific targeted and controlled combination therapy to enhance treatment efficacy is of great importance for a wide range of biomedical applications. Here, we first attempted to develop biocompatible hyaluronic acid (HA)–glutathione (GSH) conjugate stabilized gold nanoclusters (GNCs) combined with graphene oxide (GO), accompanied by loading 5‐fluorouracil (5FU), as a novel theranostic platform (HG‐GNCs/GO‐5FU, HG refers to HA‐GSH). Multifunctional HG‐GNCs possessed excellent fluorescence, photosensitivity and specific targeting ability to the cancer cells while their fluorescence and singlet oxygen generation could be strongly inhibited by GO and then effectively restored by lysosomal hyaluronidase in tumor cells. The sustained and complete release of 5FU from HG‐GNCs/GO could also be stimulated successively by enzymatic degradation of HA and light‐induced heat effect of GO under laser irradiation so that turn‐on cell imaging‐assisted synergistic therapeutic strategies associated with triple enzyme/light‐controlled chemo/photothermal/photodynamic therapy could be achieved at the same time, reducing greatly the side effects of materials to normal cells. Our study presents a novel strategy to combine targeting and bioimaging with triple therapies to enhance the antitumor effect. 相似文献
1000.
Marziyeh Rohaniyan Abolghasem Davoodnia S. Ali Beyramabadi Amir Khojastehnezhad 《应用有机金属化学》2019,33(5)
New Schiff base (SB) functionalized graphene oxide (GO) nanosheets containing phosphomolybdic counter‐anion H2PMo12O40¯ (H2PMo) were successfully prepared by grafting of 3‐aminopropyltriethoxysilane (APTS) on GO nanosheets followed by condensation with benzil and finally reaction with phosphomolybdic acid (H3PMo12O40, denoted as H3PMo) and characterized using Fourier transform infrared (FT‐IR) spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), particle size distribution, energy‐dispersive X‐ray (EDX) analysis, EDX elemental mapping, and inductively coupled plasma optical emission spectrometry (ICP‐OES). The prepared new nanomaterial, denoted as GO‐SB‐H2PMo, was shown to be an efficient heterogeneous catalyst in one‐pot, three‐component reaction of β‐naphthol, aldehydes, and dimedone, giving high yields of tetrahydrobenzo[a]xanthene‐11‐ones within short reaction times. The catalyst is readily recovered by simple filtration and can be recycled and reused several times with no significant loss of catalytic activity. 相似文献