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141.
Mohammad Bagher Gholivand Behrooz Geravandi Mohammad Hadi Parvin 《Electroanalysis》2011,23(6):1345-1351
A differential pulse anodic stripping voltammetric procedure was developed for the determination of trace amounts of iron(II) in the presence of iron(III) at a carbon paste electrode (CPE) modified with dithiodianiline and gold nanoparticle. At the pH working of 3.0, a wide concentration range from 0.1 nM to 100 nM was observed with the detection limit of 0.05 nM. The relative standard deviation for a solution containing 50 nM of iron(II) was found to be 3.11 % (n=9). Possible interferences from the coexisting ions were also investigated. The validity of the method and applicability of the sensor were successfully tested by determining of iron(II) in lentil, wheat seed and barley seed samples. 相似文献
142.
Mohammad Bagher Gholivand Mir Mahdi Abolghasemi Peyman Fattahpour 《Chromatographia》2011,74(11-12):807-815
A highly porous fiber coating material was prepared and functionalized with 3-amino propyl triethoxysilane (APTES) on hexagonally ordered nanoporous silica (SBA-15). Applicability of this coating was assessed employing a laboratory made solid-phase microextraction (SPME) device and gas chromatography?Cmass spectrometry for the simultaneous sampling and determination of trace polycyclic aromatic hydrocarbons (PAHs) from aqueous sample solutions. A one at the time optimization strategy was applied to investigate and optimize important extraction parameters such as extraction temperature, extraction time, ionic strength and sonication time. In the optimum conditions, the relative standard deviations for deionized water, spiked with selected PAHs were between 3.3 and 7.7% (n = 3), and detection limits for the studied compounds were 4.2 and 26.1 pg mL?1. No significant change was observed in the extraction efficiency of the new SPME fiber, over 50 extractions. The proposed method was successfully applied to the extraction and determination of PAHs in the waste water samples. 相似文献
143.
Adibi H Rashidi A Khodaei MM Alizadeh A Majnooni MB Pakravan N Abiri R Nematollahi D 《Chemical & pharmaceutical bulletin》2011,59(9):1149-1152
In this research, synthesis, antimicrobial and antioxidant activities of a series of catecholthioethers having benzoxazole and tetrazole moieties are described. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC) assay. The synthesized compounds were tested in vitro against three Gram-positive bacteria including Staphylococcus aureus (clinical isolated), Staphylococcus aureus ATCC 25922, Enterococcus faecium (clinical isolated), and two Gram-negative bacteria including Klebsiella pneumoniae (clinical isolated) and Pseudomonas aeruginosa 27853 and the yeast Candida albicans in comparison with control drugs. Microbiological results indicated that the synthesized compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 4-256 μg/ml. This shows compounds having tetrazole moiety were the most active against Gram-negative strains, whereas compounds having benzoxazole moiety were more active against Gram-positive ones. Also both of them showed significant antifungal activity against Candida albicans and had lower activity than the compared control drugs (Sulfamethoxazole and Fluconazole). The antioxidant activity was assessed using two methods, including, 1,1-biphenyl-2-picrylhydrazyl (DPPH) radical scavenging, and reducing power assays. Some of the catecholthioether derivatives showed antioxidant activity more than Trolox and butylated hydroxyanisole (BHA) as reference antioxidants. 相似文献
144.
Bagher Eftekhari-Sis Mahnaz Saraei Mohammad Bonyad-Bagheri 《Journal of the Iranian Chemical Society》2013,10(3):421-427
At room temperature, zirconium oxychloride (ZrOCl2·8H2O) efficiently catalyzes the direct Mannich-type reaction of a variety of in situ generated bis-imines using terephthalaldehyde and anilines with ketones in a three-component reaction at room temperature. The reaction proceeds rapidly and affords the corresponding bis-β-amino ketones in good-to-high yields with good-to-excellent anti–anti selectivity. 相似文献
145.
Ali Ramazani Nader Noshiranzadeh Bagher Mohammadi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):761-765
Protonation of the highly reactive 1:1 intermediates produced in the reaction between triphenylphosphine (or tributylphosphine) and dialkyl acetylenedicarboxylates by acetylacetone leads to sterically congested phosphorus ylides, which undergo an intermolecular Wittig reaction with ninhydrin and concomitant annulation in CH 2 Cl 2 at room temperature to produce dialkyl 3,3-diacetyl-3 a -hydroxy-8-oxo-2,3,3 a ,8-tetrahydrocyclopenta[ a ]indene-1,2-dicarboxylates in fairly high yields. 相似文献
146.
Mohammad Janghouri Ezeddin Mohajerani Mostafa M. Amini Ezzatollah Najafi 《Applied Physics A: Materials Science & Processing》2014,114(2):445-451
A novel coating method for fabrication of red OLEDs by using a new host material has been developed with the aid of a single furnace. The host material, zinc complex, was prepared from the reaction of zinc acetate and 2-methyl-8-hydroxyquinoline and after characterization by UV-vis, FT-IR, and 1H NMR spectroscopes was used as an emitting material in the fabrication of OLEDs. Since meso-tetraphenylporphyrin (TPP) and zinc complex have a close molecular weight, both materials were evaporated from a single furnace. Devices with TPP and structures of ITO/PEDOT:PSS (55 nm)/PVK (90 nm)/zinc complex:TPP (65 nm)/Al (180 nm) were fabricated; Without TPP green and with TPP red emission was achieved. The device with 2 % TPP that doped into the zinc complex showed the purest red emission among all devices. The device showed the CIE coordinates of 0.70 and 0.28 at 14 V and a maximum luminance of about 94.2 cd/m2. This new method is a promising candidate for fabrication of low cost red OLEDs with a more homogeneous layer. 相似文献
147.
Synthesis of New 1,2,3‐Triazole Derivatives Possessing 4H‐Pyran‐4‐one Moiety by 1,3‐Dipolar Cycloaddition Reaction of Azidomethyl Phenylpyrone with Various Alkynes 下载免费PDF全文
Mahnaz Saraei Bagher Eftekhari‐Sis Massomeh Faramarzi Roshanak Hossienzadeh 《Journal of heterocyclic chemistry》2014,51(5):1500-1503
A series of new 1,2,3‐triazole derivatives were synthesized by 1,3‐dipolar cycloaddition reaction of 2‐(4‐azidomethylphenyl)‐6‐phenyl‐4H‐pyran‐4‐one with different alkynes in 40–71% yields. In the case of terminal alkynes, the reaction was proceeded in the presence of Cu(I) catalyst. The structure of the synthesized compounds were confirmed by FTIR, 1H‐NMR, and 13C‐NMR spectroscopy and elemental analysis. 相似文献
148.
Mohammad Bagher Teimouri Reihaneh Bazhrang 《Monatshefte für Chemie / Chemical Monthly》2008,15(1):957-961
An efficient and clean green synthesis of highly substituted linear naphtho[2,3-b]-furan-4,9-dione derivatives, starting from 2-hydroxy-1,4-naphthoquinone, alkyl isocyanides and a variety of aldehydes, is
described. This new method provides the first example of an efficient regioselective synthetic method for the synthesis of
linear naphtho[2,3-b]-furan-4,9-dione ring systems by formation of three bonds. This [3 + 1 + 1] furannulation strategy affords furanonaphthoquinones
in moderate to high yields, using water as a cheap, non-toxic, environmentally friendly solvent, in a one-step reaction, without
the need of complicated work-up procedures. 相似文献
149.
Gholivand MB Ghasemi JB Saaidpour S Mohajeri A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(3):1158-1165
In the present paper, a sensitive, fast and suitable method for the calculation of pK(a) values of fluorescein is proposed. The effects of sodium dodecyl sulfate (SDS) and Triton X-100 (TX-100) as a surface-active agent on the acidic and basic forms, and the spectral properties of fluorescein were studied by the spectrophotometric method. The study was performed in sub-micelle surfactant concentration, and absorption spectra at 300-550 nm intervals were recorded. Stepwise acidity constants of fluorescein at pH range 1.50-10.00 and at constant ionic strength 0.1M and 25 degrees C were determined using DATAN program using pH-spectrophotometric titration data. The method is efficient, however the component spectra showed intensive overlapping. The calculated acidity constants of fluorescein in water at ionic strength 0.1 are pK(a1)=2.20, pK(a2)=4.30 and pK(a3)=6.43. The acidity constants of the dye in ethanol-water solution were studied by the same procedure. Effect of surfactants and ethanol on acidity constants and pure spectrum of each component are also discussed. 相似文献
150.
2-Acetylcyclopentanone undergoes a smooth reaction with triphenylphosphine and dialkyl acetylenedicarboxylates to produce dialkyl 2-(1-acetyl-2-oxocyclopentyl)-3-(1,1,1-triphenyl-lambda(5)-phosphanylidene)succinates. These compounds undergo intramolecular Wittig reactions in boiling benzene to produce highly strained spirocyclobutene derivatives, which spontaneously undergo ring-opening reactions to produce dialkyl (E)-2-[1-(2-oxocyclopentyliden)ethyl]-2-butenedioates. 相似文献