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81.
82.
Majid M. Heravi Masoumeh Haghighi Fatemeh Derikvand Fatemeh F. Bamoharram 《合成通讯》2013,43(21):3103-3107
A simple and effective method for tetrahydropyranylation of alcohols and phenols and the regeneration of THP ethers using a catalytic amount of H14[NaP5W30O110] is reported. 相似文献
83.
84.
Ghahremani Masoumeh Bahrami Hamed Douroudgari Hamed Vahedpour Morteza 《Structural chemistry》2020,31(1):411-421
Structural Chemistry - Sulfinamides, as an asymmetric synthesizer, especially in drug synthesis, play critical roles in organic chemistry. In this study, the gas phase ion energetics data including... 相似文献
85.
In this work,an effective,task specific,dicationic,podand-like ionic liquid was synthesized and applied to improve the capability features of click reaction.Moreover,to broaden the scope and decreasing the serious limitations of preparation methods of organic azides,a simple green procedure for the preparation of alkyl azides,the fundamental starting materials in click reactions,from alcohols under solvent-free conditions and microwave irradiation has been reported,for the first time. 相似文献
86.
Saeed Balalaie Hamid Moghimi Morteza Bararjanian Frank Rominger Hamid Reza Bijanzadeh Masoumeh Sheikhahmadi 《Journal of heterocyclic chemistry》2013,50(6):1304-1312
A highly efficient one‐pot synthesis of some new spiro‐2‐aminopyrimidinones via a three‐component reaction of cyclic ketones, methylcyanoacetate or malononitrile, and guanidinium carbonate has been developed through a domino Knoevenagel/Michael/cyclization sequence. The hydrogen bonding capacity of these compounds would make these structures especially stable. Furthermore, the antibacterial study reveals that these types of compounds exhibit good antibacterial activity. 相似文献
87.
Afshin Babaei Hossein Jafari Masoumeh Ahmadi 《Mathematical Methods in the Applied Sciences》2019,42(7):2334-2343
In this paper, a fractional order model for the spread of human immunodeficiency virus (HIV) infection is proposed to study the effect of screening of unaware infected individuals on the spread of the HIV virus. For this purpose, local asymptotic stability analysis of the disease‐free equilibrium is investigated. In addition, the model is studied for different values of the fractional order to show the relation between the variations of the reproduction number and the order of the proposed model. Finally, numerical solutions are simulated by using a predictor‐corrector method to illustrate the dynamics between susceptible individuals and unaware infected individuals. 相似文献
88.
Modification of the Electrode Surface by Ag Nanoparticles Decorated Nano Diamond‐graphite for Voltammetric Determination of Ceftizoxime 下载免费PDF全文
A modified glassy carbon electrode with a film of nano diamond? graphite nano mixture decorated with Ag nanoparticles (AgNPs? NDG/GCE) was constructed and used for sensitive voltammetric determination of ceftizoxime (CFX). Morphology of AgNPs? NDG/GCE has been examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Experimental variables such as deposited amount of the modifier suspension, pH of the supporting electrolyte and accumulation potential and time were optimized by monitoring of CV and LSV responses of CFX. The results illustrate that AgNPs? NDG/GCE exhibits an excellent electrocatalytic effect in the electro‐oxidation of CFX that leads to a considerable improvement in the corresponding anodic peak current. This also allows the development of a highly sensitive voltammetric sensor for the determination of CFX in pharmaceutical and clinical samples. Under the optimum conditions, the modified electrode showed a linear response to the concentration of CFX in the range of 0.02–7 µM with detection limit of 6 nM. The prepared modified electrode has some remarkable electrochemical properties such as simple preparation, high sensitivity, excellent repeatability and reproducibility and long‐term stability. 相似文献
89.
Ali Mehdinia Masoumeh Mashkani Ali Jabbari 《International journal of environmental analytical chemistry》2016,96(11):1091-1104
Extraction, pre-concentration and determination of trace amounts of mercury ions from water samples were investigated by magnetic solid phase extraction (MSPE) method using Fe3O4 nanoparticles decorated with polythionine as an adsorbent. A simple chemical synthesis by catalytic reaction of thionine in the presence of FeCl3 and hydrogen peroxide was used for preparation of the magnetic sorbent. Scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, vibrating sample magnetometer analysis and Fourier transform infrared spectroscopy were used to characterise the adsorbent. Mercury ions were determined by cold vapour atomic absorption spectrometry. The parameters for MSPE procedure, such as pH of the extraction solution, adsorption time, weight adsorbent, elution conditions (type, concentration and volume of the eluent), volume of the sample solution and effects of coexisting ions were investigated. The obtained optimal conditions were: sample pH of 4; sorbent amount of 4 mg; sorption time of 20 min; elution solvent of HNO3 (0.3 mol L?1)/thiourea (2% w/v) with volume of 2 mL, and breakthrough volume of 400 mL. A good linearity in the concentration range of 0.025–40 µg L?1 (R2 > 0.999) with the pre-concentration factor of 198 was obtained. The limits of detection and quantification were achieved as 0.008 and 0.025 µg L?1, respectively. Furthermore, sea and river water samples were analysed and good recoveries (97.1–99.6%) were obtained. 相似文献
90.
Masoumeh Mohammadnejad Mohsen Farhadpour Vahideh Mahdavi Mahmoud Tabrizchi 《International Journal for Ion Mobility Spectrometry》2017,20(1-2):23-30
Dichlorodiphenyl trichloroethane (DDT) as an organochlorine compound has been globally used as a pesticide for controlling soil-dwelling insects and treating diseases such as malaria and typhus. The degradation products of DDT and its metabolites have also negative effects on the environment. The present study has investigated the determination of DDT and its metabolites in water sample using ion mobility spectrometry (IMS) as a rapid and sensitive detection technique. For this purpose, DDT and its metabolites were extracted using reverse phase solid-phase extraction (SPE) from water samples. The samples were then recovered by eluting with methanol and finally, quantified using the corona discharge IMS technique. Injection and oven temperatures and the effect of dopant were optimized as experimental parameters influencing both detection and determination efficiencies. Degradation of DDT in IMS drift tube was studied and reduced mobility values of DDT and its metabolites were calculated. The developed method was validated using water sample to obtain good results for the determination of DDT at low levels (1 ng ml?1) while spiked recoveries were obtained to be between 95.0–96.7%. The proposed method based on IMS proved to be a simple, inexpensive, rapid and sensitive procedure for the fast monitoring and determination of DDT and its main metabolites in water sample. 相似文献