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排序方式: 共有414条查询结果,搜索用时 15 毫秒
1.
Structural Chemistry - Quantum chemical study of the nature of interactions between the boraphosphinine (BP) and alumaphosphinine (AlP) with some of the alkali metal cations (Li+, Na+, K+) and... 相似文献
2.
Ghorbani Bahram Ebrahimi Armin Skandarzadeh Fatemeh Ziabasharhagh Masoud 《Journal of Thermal Analysis and Calorimetry》2021,145(3):925-953
Journal of Thermal Analysis and Calorimetry - The natural gas entering the liquefaction cycle usually consists of nitrogen, ethane, propane and also heavier hydrocarbons which are economically... 相似文献
3.
The reusable acidic ionic liquid, 1-methylimidazolium tetrafluoroborate [Hmim][BF4], was found to be an effective catalyst for the insertion of α-diazoacetate into the N–H bonds of amines. The corresponding products were obtained in good yields and short reaction times via a simple procedure. The catalyst could be recycled and reused without any noticeable decrease in its activity. 相似文献
4.
We show that for an inverse semigroup S with the set idempotents E acting on S trivially from left and by multiplication from right, any bounded module derivation from \(\ell ^1(S)\) to \(({\ell ^1(S)}/{J})^*=J^{\perp }\) is inner, where J is the closed ideal generated by elements of the form \(\delta _{set}-\delta _{st}\) with \(s,t\in S\) and \(e\in E\). 相似文献
5.
Tahereh Naderi Joloudar Ali Akbar Saboury Marzieh Dehghan Shasaltaneh Seifollah Bahramikia Mohammad Ali Ebrahimi Atiyeh Ghasemi 《Journal of the Iranian Chemical Society》2017,14(11):2407-2416
A key feature in more than twenty amyloid-related diseases is the aggregation of intra-and/or extracellular misfolded proteins as amyloid fibrils. Therefore, preventing or reversing amyloid aggregation by using of small molecules is considered as useful approaches to the treatment of these diseases. We have evaluated the ability of safranal and crocin, to inhibit amyloid self-assembly of hen egg white lysozyme (HEWL), as an in vitro model system. Structural properties of HEWL in the presence of these compounds were investigated individually using thioflavin T, anilinonaphthalene-8-sulfonic acid fluorescence assays, far-UV circular dichroism and scanning electron microscopy as well as docking method. Our results showed that incubation of HEWL with either crocin or safranal at various concentrations leads a significant inhibition in the rate of amyloid formation. Docking analysis revealed crocin and safranal interact with the central hydrophobic region of lysozyme through van der Waals interaction. Hydroxyl group in crocin through hydrogen bonds connected to the several hydrophilic amino acids of lysozyme, while in safranal there are just one aldehyde group that through hydrogen bonds connected to aspartic acid in lysozyme. It can be concluded that both hydrophobic and hydrophilic groups contribute to lower lysozyme fibril accumulation. 相似文献
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Structural Chemistry - Ab initio calculations have been performed to study the complexes between the noble gas elements (Ae = Ne, Ar, Kr) with a series of benzene isoelectronic heterocyclic... 相似文献
8.
M. Vogel G. Birkl M. S. Ebrahimi D. von Lindenfels A. Martin G. G. Paulus W. Quint S. Ringleb Th. Stöhlker M. Wiesel 《Hyperfine Interactions》2015,230(1-3):65-71
We present two Penning trap experiments concerned with different aspects of the physics of extreme electromagnetic fields, the ARTEMIS experiment designed for bound-electron magnetic moment measurements in the presence of the extremely strong fields close to the nucleus of highly charged ions, and the HILITE experiment, in which well-defined ion targets are to be subjected to high-intensity laser fields. 相似文献
9.
Application of a dispersive micro‐solid‐phase extraction method for pre‐concentration and ultra‐trace determination of cadmium ions in water and biological samples 下载免费PDF全文
Mohammad Behbahani Ali Veisi Fariborz Omidi Aminreza Noghrehabadi Ali Esrafili Mohammad Hossein Ebrahimi 《应用有机金属化学》2018,32(3)
A method for the trace determination of cadmium ions in water, human urine and human blood serum samples using ultrasonic‐assisted dispersive micro‐solid‐phase extraction (UA‐D‐μSPE) was developed. Silica‐coated magnetic nanoparticles were coated with polythiophene, and the resulting sorbent was characterized using thermogravimetry, differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectrometry and X‐ray diffraction. Following UA‐D‐μSPE, cadmium ions were quantified using graphite furnace atomic absorption spectrometry. A Box–Behnken design was used for optimization of important sorption and desorption parameters in UA‐D‐μSPE: in the sorption step, pH of solution, sorption amount and sonication time for sorption; in the desorption step, concentration of eluent, volume of eluent and sonication time. The optimum conditions for the method were: pH of solution, 7.5; sonication time for sorption, 3 min; sorption amount, 35 mg; type and concentration of eluent, HCl and 1.1 mol l?1; volume of eluent, 360 μl; sonication time for desorption, 110 s. Under the optimized conditions the limit of detection and relative standard deviation for the detection of cadmium ions by UA‐D‐μSPE were found to be 0.8 ng l?1 and <6%, respectively. 相似文献
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