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41.
High selectivity of a biomarker is a basic requirement when it is used for diagnosis, prognosis and treatment of a disease. The artificial gel antibodies, which we synthesise by a molecular imprinting method, have this property not only for proteins, but also for bioparticles, such as viruses and bacteria. However, diagnosis of a disease requires not only that the biomarker can be “fished out” from a body fluid with high selectivity, but also that its concentration in the sample can rapidly be determined and preferably by a simple technique. This paper deals primarily with the development of a spectrophotometric method, which is so simple and fast that it can be used with advantage in a Doctor's Office. The development of this method was not straight‐forward. However, by modifications of the performance of these measurements we can now design standard curves in the form of a straight line, when we plot the true (not the recorded “apparent” absorption) against known protein concentrations. In an additional publication (see the following paper in this issue of JSS) we show an application of such a plot: determination of the concentration of albumin in serum and cerebrospinal fluid from patients with neurological disorders to investigate whether albumin is a biomarker for these diseases. 相似文献
42.
Roghayeh Shabanlouei Peyman Najafi Moghadam Nasim Movagharnezhad Amir Reza Fareghi 《Polymer Science Series B》2016,58(5):574-579
In the present work new conductive nanostructures based on poly (acrylamide-co-maleic acid) (PAAMA) and polyaniline were prepared. The template polymerization of aniline was conducted in the aqueous solution of PAAMA with different ratios (w/w%) of aniline to polyacid. The prepared composite was characterized by FTIR and UV–Vis spectroscopy, SEM, electrical conductivity measurements and solubility tests. 相似文献
43.
Structural studies of dimethyl sulfoxide (DMSO) reductases were hampered by modification of the active site during purification. We report an X-ray absorption spectroscopic analysis of the molybdenum active site of Escherichia coli DMSO reductase contained within its native membranes. The enzyme in these preparations is expected to be very close to the form found in vivo. The oxidized active site was found to have four Mo-S ligands at 2.43 A, one Mo=O at 1.71 A, and a longer Mo-O at 1.90 A. We conclude that the oxidized enzyme is a monooxomolybdenum(VI) species coordinated by two molybdopterin dithiolenes and a serine. The bond lengths determined for E. coli DMSO reductase are very similar to those determined for the well-characterized Rhodobacter sphaeroides DMSO reductase, suggesting similar active site structures for the two enzymes. Furthermore, our results suggest that the form found in vivo is the monooxobis(molybdopterin) species. 相似文献
44.
Theoretical study on the atmospheric formation of sulfur trioxide as the primary agent for acid rain
Morteza Vahedpour Moein Goodarzi Nasim Hajari Fariba Nazari 《Structural chemistry》2011,22(4):817-822
The reaction mechanism of SO2 with O3 on the singlet potential energy surface has been investigated theoretically at the G3MP2B3//B3LYP/6-311+G(3df) level of theory.
The reactants are initially associated with adducts IN1(O2S–OOO) and IN2(OS-cyclic O4) in a barrier-less process. Subsequently, these adducts undergo isomerization and dissociation processes to produce cis-OSOO + 3O2, SO3(C
s
) + 3O2 and SO3(D
3h
) + 3O2 products. The SO3(D
3h
) + 3O2 is major product and the cis-OSOO + 3O2 and SO3(C
s
) + 3O2 are minor products. No stable pathway has been found for the formation of trans-OSOO and cyclic-SOOO isomers in the reaction of SO2 + O3. For major product, the rate constant of SO2 + O3 reaction is 2.30 × 10−23 cm3 molecule−1 s−1, at room temperature and atmospheric pressure. 相似文献
45.
Nasim Asghari Lalami Hassan Hosseini Monfared Hashem Noei Peter Mayer 《Transition Metal Chemistry》2011,36(6):669-677
Three new binuclear vanadium(V) complexes of bis(aryl)adipohydrazones (H4L1 = bis((2-hydroxynaphthalen-1-yl)methylene)adipohydrazide, H4L2 = bis(5-bromo-2-hydroxybenzylidene)adipohydrazide, and H4L3 = bis(2-hydroxy-3-methoxybenzylidene)adipohydrazide) were synthesized by direct reaction of [VO(acac)2] with the hydrazone ligands. The ligands and complexes were characterized by FT–IR, UV–Vis, and NMR spectroscopic methods.
The crystal structures of the complexes of L1 and L3 were determined by X-ray analyses. The solid-state structure of the complex of L1 features a 1D hydrogen-bonded chain from N⋯H–O hydrogen bonding. The catalytic activities of these complexes have been tested
in the oxidation of various hydrocarbons using H2O2 as the terminal oxidant. Generally, good to excellent conversions have been obtained. 相似文献
46.
Shama Nasim 《Tetrahedron letters》2009,50(3):257-150
N-Chlorosuccinimide has been identified as a convenient and safe alternative oxidant for the oxidative condensation of isothiocyanates and isocyanates to afford 1,2,4-thiadiazolidine-3,5-diones. 相似文献
47.
Nasim Tajaddini Mahdiyeh Talebizadeh Mohammad Anary-Abbasinejad 《Tetrahedron letters》2019,60(4):366-370
An efficient one-pot method for the synthesis of new substituted cylopentenone derivatives is described via reaction of arylglyoxals and acetylacetone with aliphatic amines. This reaction was carried out in aqueous media in the absence of any catalyst or promoter to produce substituted cylopentenone in high yield. 相似文献
48.
Setareh Habibzadeh Ghasem Firouzzadeh Pasha Mahmood Tajbakhsh Nasim Amiri Andi Ehsan Alaee 《中国化学会会志》2019,66(8):934-944
A new solid acid catalyst, consisting of 12‐phosphotungstic heteropoly acid (HPW) supported on graphene oxide/silica nanocomposite (GO@SiO2), has been developed via immobilizing HPW onto an amine‐functionalized GO/SiO2 surface through coordination interaction (GO@SiO2‐HPW). The GO@SiO2‐HPW nanocomposite was characterized by Fourier transform infrared (FT‐IR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and powder X‐ray diffraction (XRD). The prepared nanocomposite could be dispersed homogeneously in water and further used as a heterogeneous, reusable, and efficient catalyst for the synthesis of benzimidazoles and benzothiazoles by the reaction of 1,2‐phenelynediamine or 2‐aminothiophenol with different aldehydes. 相似文献
49.
Mohammadreza Alizadeh‐Ghodsi Mohammad Pourhassan‐Moghaddam Ali Zavari‐Nematabad Brian Walker Nasim Annabi Abolfazl Akbarzadeh 《Particle & Particle Systems Characterization》2019,36(2)
Quantum dots (QDs) with a nanoscale size range have attracted significant attention in various areas of nanotechnology due to their unique properties. Different strategies for the synthesis of QD nanoparticles are reported in which various factors, such as size, impurities, shape, and crystallinity, affect the QDs fundamental properties. Consequently, to obtain QDs with appropriate physical properties, it is required to select a synthesis method which allows enough control over the surface chemistry of QDs through fine‐tuning of the synthesis parameters. Moreover, QDs nanocrystals are recently used in multidisciplinary research integrated with biological interfaces. The state‐of‐the‐art methods for synthesizing QDs and bioconjugation strategies to provide insight into various applications of these nanomaterials are discussed herein. 相似文献
50.
Rukhsana Kouser G Tasneem Muhammad Saleem Shahzad S Sardar Amjad Ali M H Nasim M Salahuddin 《中国物理 B》2017,26(7):75201-075201
We present the preliminary results of our code OPAQS(opacity calculation using quantum statistical model) that is based on the self consistent Hartree-Fock-Slater model for the average atom. The code is capable of performing robust calculations of average charge state, frequency-dependent and mean opacities. The accuracy of the atomic model is verified by comparing the calculations of average charge state with various published results. The monochromatic opacities for iron computed at different sets of temperatures and densities are compared with LEDCOP. The Rosseland and Planck opacities for iron and aluminum are validated with some state-of-the-art codes. The results are in good agreement with the published data. 相似文献