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51.
Farzinpour Masoud Toghraie Davood Mehmandoust Babak Aghadavoudi Farshid Karimipour Arash 《Journal of Thermal Analysis and Calorimetry》2020,140(6):2625-2631
Journal of Thermal Analysis and Calorimetry - For the first time, double phosphates(V) Zn3Cr4(PO4)6 and Mg3Cr4(PO4)6 were synthesized by non-waste solid-state reaction, performed in the temperature... 相似文献
52.
Fatemeh Fadaei Michelle Seifert Joshua R. Raymond David eha Natalia Kulik Babak Minofar Mark P. Heitz 《Molecules (Basel, Switzerland)》2022,27(1)
Ionic liquids (ILs) have become nearly ubiquitous solvents and their interactions with biomolecules has been a focus of study. Here, we used the fluorescence emission of DAPI, a groove binding fluorophore, coupled with molecular dynamics (MD) simulations to report on interactions between imidazolium chloride ([Imn,1]+) ionic liquids and a synthetic DNA oligonucleotide composed entirely of T/A bases (7(TA)) to elucidate the effects ILs on a model DNA duplex. Spectral shifts on the order of 500–1000 cm−1, spectral broadening (~1000 cm−1), and excitation and emission intensity ratio changes combine to give evidence of an increased DAPI environment heterogeneity on added IL. Fluorescence lifetimes for DAPI/IL solutions yielded two time constants 0.15 ns (~80% to 60% contribution) and 2.36–2.71 ns for IL up to 250 mM. With DNA, three time constants were required that varied with added IL (0.33–0.15 ns (1–58% contribution), ~1.7–1.0 ns (~5% contribution), and 3.8–3.6 ns (94–39% contribution)). MD radial distribution functions revealed that π-π stacking interactions between the imidazolium ring were dominant at lower IL concentration and that electrostatic and hydrophobic interactions become more prominent as IL concentration increased. Alkyl chain alignment with DNA and IL-IL interactions also varied with IL. Collectively, our data showed that, at low IL concentration, IL was primarily bound to the DNA minor groove and with increased IL concentration the phosphate regions and major groove binding sites were also important contributors to the complete set of IL-DNA duplex interactions. 相似文献
53.
Zeenat Zara Deepti Mishra Saurabh Kumar Pandey Eva Csefalvay Fatemeh Fadaei Babak Minofar David eha 《Molecules (Basel, Switzerland)》2022,27(1)
The effect of aqueous solutions of selected ionic liquids solutions on Ideonella sakaiensis PETase with bis(2-hydroxyethyl) terephthalate (BHET) substrate were studied by means of molecular dynamics simulations in order to identify the possible effect of ionic liquids on the structure and dynamics of enzymatic Polyethylene terephthalate (PET) hydrolysis. The use of specific ionic liquids can potentially enhance the enzymatic hydrolyses of PET where these ionic liquids are known to partially dissolve PET. The aqueous solution of cholinium phosphate were found to have the smallest effect of the structure of PETase, and its interaction with (BHET) as substrate was comparable to that with the pure water. Thus, the cholinium phosphate was identified as possible candidate as ionic liquid co-solvent to study the enzymatic hydrolyses of PET. 相似文献
54.
Kaveh Amini Heinz-Bernhard Kraatz 《International journal of environmental analytical chemistry》2016,96(9):836-844
The need for effective and efficient methods for pathogen detection in water is as serious as ever due to the health risk posed to human population by the consumption of pathogen-contaminated water. One of the important research streams which have been focused on by researchers for development of novel techniques for this purpose is biosensor technologies. Using different bio-recognition elements and transduction methodologies, biosensors have the potential to detect their analyte of interest in a fast and highly specific manner. Different pathogenic agents can be recognised by toll-like receptors (TLRs). The innate immune system of higher organisms employs TLRs for triggering intracellular signalling and induction of the expression of immune response genes. In this report, we explore the challenges associated with employing TLRs for pathogen detection in water samples. Although methods using TLR expressing cells also have been discussed, the focus of this review is on using TLR proteins as the bio-recognition elements in biosensors. 相似文献
55.
56.
Aleksandar Donev Vasily V. Bulatov Tomas Oppelstrup George H. Gilmer Babak Sadigh Malvin H. Kalos 《Journal of computational physics》2010,229(9):3214-3236
We develop an asynchronous event-driven First-Passage Kinetic Monte Carlo (FPKMC) algorithm for continuous time and space systems involving multiple diffusing and reacting species of spherical particles in two and three dimensions. The FPKMC algorithm presented here is based on the method introduced in Oppelstrup et al. [10] and is implemented in a robust and flexible framework. Unlike standard KMC algorithms such as the n-fold algorithm, FPKMC is most efficient at low densities where it replaces the many small hops needed for reactants to find each other with large first-passage hops sampled from exact time-dependent Green’s functions, without sacrificing accuracy. We describe in detail the key components of the algorithm, including the event-loop and the sampling of first-passage probability distributions, and demonstrate the accuracy of the new method. We apply the FPKMC algorithm to the challenging problem of simulation of long-term irradiation of metals, relevant to the performance and aging of nuclear materials in current and future nuclear power plants. The problem of radiation damage spans many decades of time-scales, from picosecond spikes caused by primary cascades, to years of slow damage annealing and microstructure evolution. Our implementation of the FPKMC algorithm has been able to simulate the irradiation of a metal sample for durations that are orders of magnitude longer than any previous simulations using the standard Object KMC or more recent asynchronous algorithms. 相似文献
57.
Babak Momeni Ehsan Shah Hosseini Murtaza Askari Mohammad Soltani Ali Adibi 《Optics Communications》2009,282(15):3168-697
A combination of negative refraction and diffraction compensation in a superprism-based photonic crystal structure is used to demonstrate a compact on-chip photonic crystal spectrometer. This structure provides strong dispersion and signal isolation, which are essential for forming an efficient and compact spectrometer. Performance of these spectrometers as spectral pattern detectors is discussed. The experimental results show that a PC structure with 80 μm × 220 μm dimension can locate a single spectral feature with better than 10 pm accuracy over a bandwidth of 50 nm around 1550 nm center wavelength at an output signal-to-noise ratio of 13 dB. 相似文献
58.
A. K. Babak S. S. Kil'chitskaya V. I. Strikha V. A. Afanas'ev A. V. Ievskii N. G. Lozovaya 《Russian Physics Journal》1985,28(12):1022-1025
The relative importance of the contribution of two mechanisms, that of the change in the collection of photocurrent carriers and that of the shift of the edge of fundamental absorption of light in strong electric fields in Schottky photodiodes, to the observed spectral dependence of the avalanche photocurrent is asessed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 83–86, December, 1985. 相似文献
59.
A unique combination of a supported cobalt complex and the first example of supported NHPI in acetic acid gives a surprisingly stable heterogeneous catalytic system for the selective aerobic oxidation of methylaromatics to benzaldehydes at atmospheric pressure. 相似文献
60.
Daniel C. Steigerwald Bardia Soltanzadeh Aritra Sarkar Cecilia C. Morgenstern Richard J. Staples Babak Borhan 《Chemical science》2021,12(5):1834
Intermolecular asymmetric haloamination reactions are challenging due to the inherently high halenium affinity (HalA) of the nitrogen atom, which often leads to N-halogenated products as a kinetic trap. To circumvent this issue, acetonitrile, possessing a low HalA, was used as the nucleophile in the catalytic asymmetric Ritter-type chloroamidation of allyl-amides. This method is compatible with Z and E alkenes with both alkyl and aromatic substitution. Mild acidic workup reveals the 1,2-chloroamide products with enantiomeric excess greater than 95% for many examples. We also report the successful use of the sulfonamide chlorenium reagent dichloramine-T in this chlorenium-initiated catalytic asymmetric Ritter-type reaction. Facile modifications lead to chiral imidazoline, guanidine, and orthogonally protected 1,2,3 chiral tri-amines.Intermolecular haloamination reactions are challenging due to the high halenium affinity of the nitrogen atom. This is circumvented by using acetonitrile as an attenuated nucleophile, resulting in an enantioselective halo-Ritter reaction. 相似文献