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51.
The aim of this letter is to confirm the achievements in [1] and answer all the mentioned comments in [2]. Meanwhile some other drawbacks in the comment paper [2] are also presented in this paper.  相似文献   
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53.
Palladium nanoparticles (2–8 nm) supported on gum arabic has been prepared under green conditions in water. Gum arabic has been used as both support and reducing agent. These nanoparticles have been characterized by UV–Vis, XRD and EDX spectra as well as SEM and TEM images. The nanoparticles have been applied as the catalyst in Mizoroki-Heck reaction of different aryl halides (I, Br, Cl) with butyl acrylate in the presence of n-Pr3N under solvent-free conditions at 140 °C. The reusability of the catalyst was also checked for five consecutive runs.  相似文献   
54.
The effects of 24 kHz and 1.7 MHz ultrasonic waves on heat transfer from a thin platinum wire are investigated. The results revealed that the 1.7 MHz ultrasound waves could increase the heat transfer rate more efficiently than the lower frequency one. The CFD modeling of ultrasonication was performed to compare heat transfer, predict fluid flow patterns. The CFD results were validated by the experimental results with an excellent agreement.  相似文献   
55.
In this work, a novel Cu?zeolite A/graphene modified glassy carbon electrode was applied for the determination of rutin. The Cu?zeolite A/graphene composites were prepared using copper doped zeolite A and graphene oxide as the precursor, subsequently reduced by chemical agents. Based on the Cu?zeolite A/graphene modified electrode, the overpotential of the rutin oxidation was lowered by ~300 mV. Also the proposed Cu?zeolite A/graphene modified electrode showed higher electrocatalytic performance than zeolite A/graphene electrode or graphene modified electrode. The electrochemical behavior of copper incorporated in the zeolite A modified electrode illustrated the adsorption-controlled reaction at the modified electrode. The behavior of electrocatalytic oxidation of rutin at the modified electrode was investigated. The diffusion coefficient of rutin was equal to 4.2 × 10–7 cm2/s. A linear calibration graph was obtained for rutin over the concentration range of 2.3 × 10–7–2.5 × 10–3 M. The detection limit for rutin was 1.2 × 10–7 M. The RSDs of 10 replicate measurements performed on a single electrode at rutin concentrations between 2.3 × 10–7–2.5 × 10–3 M were between 1.1 and 2.1%. Study of the influence of potentially interfering substances on the peak current of rutin showed that the method was highly selective. The proposed electrode was used for the determination of rutin in real samples with satisfactory results.  相似文献   
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A multiple-primer DNA sequencing approach suitable for genotyping, detection and identification of microorganisms and viruses has been developed. In this new method two or more sequencing primers, combined in a pool, are added to a DNA sample of interest. The oligonucleotide that hybridizes to the DNA sample will function as a primer during the subsequent DNA sequencing procedure. This strategy is suited for selective detection and genotyping of relevant microorganisms and samples harboring different DNA targets such as multiple variant/infected samples as well as unspecific amplification products. This method is used here in a model system for detection and typing of high-risk oncogenic human papilloma viruses (HPVs) in samples containing multiple infections/variants or unspecific amplification products. Type-specific sequencing primers were designed for four of the most oncogenic (high-risk) HPV types (HPV-16, HPV-18, HPV-33, and HPV-45). The primers were combined and added to a sample containing a mixture of one high-risk (16, 18, 33, or 45) and one or two low-risk types. The DNA samples were sequenced by the Pyrosequencing technology and the Sanger dideoxy sequencing method. Correct genotyping was achieved in all tested combinations. This multiple-sequencing primer approach also improved the sequence data quality for samples containing unspecific amplification products. The new strategy is highly suitable for diagnostic typing of relevant species/genotypes of microorganisms.  相似文献   
58.
A new simple and reliable method has been developed to selectively separate and concentrate ultra trace amounts of copper ion in aqueous samples for subsequent measurement by atomic absorption spectrometry (AAS). The Cu2+ ions are adsorbed selectively and quantitatively during passage of aqueous solutions through octadecyl silica membrane disks modified with bis(2-hydroxyphenylamino) glyoxime. The retained copper ions then stripped from the disk with a minimal amount of 0.2 M nitric acid solution as eluent, and determined by AAS. The proposed method permitted large enrichment factors of about 100 or higher.The limit of detection of the proposed method is 0.004 ng ml−1. The maximum capacity of the membrane disks modified with 25 mg of ligand was found to be 280±32 μg of copper(II). The effects of various cationic interferences on the percent recovery of copper in binary mixtures were studied.The method was successfully applied to the recovery and determination of copper in several water samples.  相似文献   
59.
A rapid and easy procedure for direct conversion of TMS-ethers to their acetates catalyzed by cerium(IV) ammonium nitrate (CAN) immobilized on n-butylpyridinium tetrachloroferrate ([nbp]FeCl4) as a room temperature ionic liquid under microwave irradiation was developed. This methodology is enough mild so that the acid sensitive groups such as methoxy, furyl or thiophenyl were remained intact. No side products were observed by this method.  相似文献   
60.
The muscarinic acetylcholine receptor family is a highly sought-after target in drug and molecular imaging discovery efforts aimed at neurological disorders. Hampered by the structural similarity of the five subtypes’ orthosteric binding pockets, these efforts largely failed to deliver subtype-selective ligands. Building on our recent successes with arecaidine-derived ligands targeting M1, herein we report the synthesis of a related series of 11 hydroxylated arecaidine esters. Their physicochemical property profiles, expressed in terms of their computationally calculated CNS MPO scores and HPLC-logD values, point towards blood–brain barrier permeability. By means of a competitive radioligand binding assay, the binding affinity values towards each of the individual human mAChR subtypes hM1hM5 were determined. The most promising compound of this series 17b was shown to have a binding constant towards hM1 in the single-digit nanomolar region (5.5 nM). Similar to our previously reported arecaidine-derived esters, the entire series was shown to act as hM1R antagonists in a calcium flux assay. Overall, this study greatly expanded our understanding of this recurring scaffolds’ structure–activity relationship and will guide the development towards highly selective mAChRs ligands.  相似文献   
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