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261.
Kavosh Majlesi Mohammadreza Gholamhosseinzadeh Saghar Rezaienejad 《Journal of solution chemistry》2010,39(5):665-679
The main aim of this research is to study the complexation of molybdenum(VI) with methyliminodiacetic acid in NaClO4 aqueous solutions at pH = 6.00 and ionic strengths (0.1<I/mol⋅dm−3<1.0) at 25 °C by using potentiometric and UV spectrophotometric measurements in order to obtain thermodynamic stability constants
at I=0 mol⋅dm−3. A comparison with previous literature data was made for the stability constants, though few data were available. The stability
constants data have been analyzed and interpreted by using extended Debye-Hückel theory, specific ion interaction theory and
parabolic model. Finally it might be concluded that parabolic model applies better for this complexation reaction. 相似文献
262.
Essential oil (EO) compositions of flowers and fruits of Hypericum perforatum L. and Hypericum scabrum L. growing wild in Kashan, central Iran, were determined by simultaneous steam distillation-solvent extraction method and analysed using GC-MS technique. Analysis revealed 28 identified compounds for H. perforatum, with two main components being α-pinene (25.36%) and α-amorphene (12.12%). Thirty-five compounds were identified in H. scabrum L. representing 98.60% of the oil with α-pinene (70.21%) and p-mentha-1,5-dien-8-ol (2.89%) as main components. Some new compounds were found in significant quantities which were not found in other chemotypes. The antioxidant activities of the EOs evaluated for the first time in this study using β-carotene bleaching and DPPH assays seemed to be attributed directly to α-pinene contents in them. Antibacterial activities of both mentioned EOs were higher than that of their main constituent, α-pinene, against Staphylococcus aureus and Escherichia coli. 相似文献
263.
Mohammadreza Ganjali Mojtaba Shamsipur 《Journal of inclusion phenomena and macrocyclic chemistry》1995,23(1):41-51
The formation of ammonium, anilinium, hydrazinium and pyridinium ion complexes with the crown ethers 18-crown-6 (18C6) and 1,10-diaza-18-crown-6 (C22) and the cryptand C222 in different binary ethanol-water mixtures has been studied by a competitive polarographic method using a Pb2+/Pb(Hg) couple as a sensitive electro-chemical probe. Lead ion was found to form very stable complexes with the ligands used, in all solvent mixtures studied; Pb2+–C222 cryptate revealed a pronounced cryptate effect compared to the corresponding complexes with the monocyclic crown ethers used. In all solvent mixtures studied, the stability of the resulting 11 complexes between the protonated amines and macrocyclic ligands used vary in the order C22>C222>18C6. The observed selectivity order of each macrocyclic ligand used for different protonated amines is discussed based on the chemical and structural features of the host-guest partners in solution. In all cases studied there is an inverse linear relationship between the complex formation constants and the mole fraction of water in the mixed solvent. 相似文献
264.
Mohammadreza Ghandforoush-Sattari Siminozar Mashayekhi Mahboub Nemati Philipp A. Routledge 《Chromatographia》2009,69(11-12):1427-1430
Taurine is an amino acid which is not incorporated into proteins but found in the cytosol of many mammalian cells, in high concentrations (2–30 mM). Increase in plasma taurine concentration has already been reported after surgical trauma, X-radiation, muscle necrosis, carbon tetrachloride-induced liver damage, and paracetamol overdose. Plasma taurine concentration was measured using LC with fluorescence detection following derivatization by o-phtalaldehyde plus 3-mercapto-propionic acid and α-aminobutyric acid as internal standard. Under these conditions the retention time of taurine was 10 min. This method was sensitive enough, to quantify 150 pg mL?1 and detect 50 pg mL?1 of taurine ranging normally between 65 and 179 mmol L?1 (8–22 μg mL?1). The validated method allowed simple determination of human plasma taurine in pharmacokinetic and biomarker studies. 相似文献
265.
Yasaman Zamani Mohammad Rabiee Mohammad Ali Shokrgozar Shahin Bonakdar Mohammadreza Tahriri 《Applied biochemistry and biotechnology》2013,171(6):1513-1524
The aim of this study was to obtain a better insight of how nano-fibrous scaffolds can affect human mesenchymal stem cells responses. Therefore, in this study, using electrospinning technique, poly(vinyl alcohol) (PVA) nano-fibers with two different patterns were prepared. In the first structure, PVA nano-fibers were oriented randomly and in the second structure, nano-fibers were electrospun in such a way that a special pattern was obtained. In order to enhance their stability, scaffolds were cross-linked using glutaraldehyde vapor. RGD immobilization was used to improve cell adhesion properties of the scaffolds. SEM micrographs demonstrated that the cell adhesion was effectively enhanced after RGD immobilization and higher cell densities were observed on RGD-modified scaffolds. Randomly oriented nano-fibers showed better cell adhesion compared to patterned structure. Patterned structure also revealed slightly lower cell viability compared to random nano-fibers. Finally, it was assumed that randomly oriented nano-fibers provide a more favorable surface for cells. 相似文献
266.
Siavash Riahi Eslam Pourbasheer Mohammad Reza Ganjali Parviz Norouzi Ali Zeraatkar Moghaddam 《中国化学会会志》2008,55(5):1086-1093
267.
Mohammadreza Khanmohammadi Amir Bagheri Garmarudi 《Trends in analytical chemistry : TRAC》2011,30(6):864-874
Diagnosis of cancer is one of the most important aspects of medical research and has become the main aim of biomedical investigations. Misdiagnosis is the main drawback in most of the diagnostic routes introduced, while some of these methods are invasive and expensive.Recently, infrared spectroscopy (IR) was proposed as a rapid, accurate and sensitive technique in biomedical research, especially for detection of patterns of illness. We discuss research into cancer detection by IR, the role of data processing in quality assurance of the results obtained and novel proposals, such as bio-fluid analysis for diagnosis. We conclude that IR provides a novel green analytical chemistry approach to clinical oncology and cancer research. 相似文献
268.
Mohammed Bouchakour Yazid Derouiche Zohra Bouberka Christophe Beyens Lahcène Mechernène Farid Riahi 《Liquid crystals》2013,40(11):1527-1536
This contribution focuses on a detailed investigation of the relationship between the method of polymerisation/cross-linking, such as slow and rapid UV radiation, and high voltage accelerated electron beam (EB), and the obtained physical properties including phase diagrams, polymerisation and phase separation kinetics, morphologies and electro-optic responses of polypropyleneglycoldiacrylate (PPGDA) monomers, in the presence of the nematic liquid crystal E7. The longer the spacing between double bonds, the more rapid was the photopolymerisation under both UV systems; however, the reverse was proved under EB. More homogenous and regular morphologies were obtained under EB curing.The electro-optical responses of various polymer dispersed liquid crystals (PDLCs) systems exhibited remarkable differences between the UV-cured samples and those cured by the EB technique. It was found that the threshold and saturation voltages considerably increased in the case of the UV-cured systems. Other results involving the contrast ratio, which is higher for EB-cured systems, confirm their higher quality, although the rapid photopolymerisation UV source was employed, which slightly improved the electro-optical responses. Moreover, EB curing leads to high enough conversions without a photoinitiator, which may act as an impurity that might have a strong impact on the electro-optical performance of the obtained PDLCs. 相似文献
269.
Somayeh Tajik Hadi Beitollahi Zahra Dourandish Peyman Mohammadzadeh Jahani Iran Sheikhshoaie Mohammad Bagher Askari Parisa Salarizadeh Fariba Garkani Nejad Dokyoon Kim Soo Young Kim Rajender S. Varma Mohammadreza Shokouhimehr 《Electroanalysis》2022,34(7):1065-1091
Non-precious transition metal oxide nanomaterials offer numerous opportunities for various cost-effective electrochemical applications. This review article features the design and advancement of such nanomaterials with unique features applied for the fabrication of electrochemical devices. Also, it discusses various new syntheses of transition metal oxide nanoparticles (TMO NPs) via multiple chemicophysical and biological procedures. Further, the novel appliances of the TMO NPs with varying sizes and morphologies are appraised. The advantages and challenges of a number of investigations on the TMO NPs towards electrochemical applications are addressed with their standpoint of cost-effectiveness, applicability, and the efficiency of the introduced nanostructures for the industrial applications. 相似文献
270.
Heydari Zahra Abdy Hamed Ghaziani Mohammad Pouya Kolahdouz Mohammadreza Asl-Soleimani Ebrahim Masnadi-Shirazi Mostafa 《Journal of Solid State Electrochemistry》2021,25(2):583-590
Journal of Solid State Electrochemistry - Organometallic halide perovskites have been arisen as a class of multi-purpose materials with exciting applications in optoelectronic devices such as solar... 相似文献