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61.
Fariba Fathi Laleh Majari‐Kasmaee Ahmad Mani‐Varnosfaderani Anahita Kyani Mohammad Rostami‐Nejad Kaveh Sohrabzadeh Nosratollah Naderi Mohammad Reza Zali Mostafa Rezaei‐Tavirani Mohsen Tafazzoli Afsaneh Arefi‐Oskouie 《Magnetic resonance in chemistry : MRC》2014,52(7):370-376
The present study was designed to search for metabolic biomarkers and their correlation with serum zinc in Crohn's disease patients. Crohn's disease (CD) is a form of inflammatory bowel disease that may affect any part of the gastrointestinal tract and can be difficult to diagnose using the clinical tests. Thus, introduction of a novel diagnostic method would be a major step towards CD treatment. Proton nuclear magnetic resonance spectroscopy (1H NMR) was employed for metabolic profiling to find out which metabolites in the serum have meaningful significance in the diagnosis of CD. CD and healthy subjects were correctly classified using random forest methodology. The classification model for the external test set showed a 94% correct classification of CD and healthy subjects. The present study suggests Valine and Isoleucine as differentiating metabolites for CD diagnosis. These metabolites can be used for screening of risky samples at the early stages of CD diagnoses. Moreover, a robust random forest regression model with good prediction outcomes was developed for correlating serum zinc level and metabolite concentrations. The regression model showed the correlation (R2) and root mean square error values of 0.83 and 6.44, respectively. This model suggests valuable clues for understanding the mechanism of zinc deficiency in CD patients. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
62.
Naderi Mahnaz Shamirian Armen Edrisi Mohammad 《Journal of Sol-Gel Science and Technology》2011,58(2):557-563
In the present work nano crystalline copper aluminate (CuAl2O4) has been synthesized by the Pechini method using aqueous solutions containing corresponding metal nitrates. A Taguchi L4 statistical design was employed for investigating the most effective factors on the synthesis conditions and their interactions
and production optimization. Nano crystalline CuAl2O4 particles with crystal size between 17 and 26 nm were obtained. The product characterized by XRD, FT-IR, DLS and TGA. The
morphological properties have investigated using SEM. The photocatalytic degradation was investigated using methyl orange
under the irradiation of visible light. 相似文献
63.
64.
Robert R. Holmes Roberta O. Day V. Chandrasekhar Soheila Shafeizad John J. Harland Denise N. Rau 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):91-98
Abstract The synthesis of [PhSn(O)O2CC6H11]6 represents the first example of tin(IV) in a drum-shaped molecule. The formation of the dimeric composition, [(MeSn(O)O2CC6H11)2(MeSn(O2CC6H11)3]2, appears to be an intermediate hydrolysis product on the way to the drum composition. The X-ray structure reveals an “unfolded” drum array. The distannoxane unit which is represented as the sides of the drum is found in additional new dimeric compositions, [(SCH2CH2O)2SnCl]2[H][Et4N], [((CN)2C2S2)2SnOH]2, and [BuSnCl2(OH) · H2O]2. These all have six-coordinated tin atoms which contrasts to the dimeric aryl distannoxanes recently isolated, [Ph2(Cl)SnOSnPh2(X)]2, X = OH, Cl, containing five-coordinated tin. Also isolated are the new ring containing, five-coordinated tin derivatives, [(SCH2CH2S)2Sn]2[SCH2CH2S][Et3NH]2 and [(SC(CN)C(CN)S)2SnMe][Et4N]. The former has two trigonal bipyramidal tin atoms while the latter composition has a square pyramidal geometry. Related ring systems of new five-coordinated derivatives of silicon, germanium, arsenic, and antimony that span the range between the two ideal five-coordinated geometries also have been structurally characterized. 相似文献
65.
Zoghi Ali T. Shokouhi Mohammad Naderi Fahimeh Abbasghorbani Maryam Fatehi Azita Pouladi Babak Adhami Mohammad Amin 《Journal of solution chemistry》2022,51(1):84-96
Journal of Solution Chemistry - Hydrogen sulfide and carbonyl sulfide represent undesirable impurities in a variety of industrial gas streams such as natural gas, liquefied natural gas and... 相似文献
66.
Novel cationic polyelectrolytes with a brush-on-brush structure of poly(ethylene oxide) (PEO) side chains and a charge-containing polyacrylate backbone were synthesized. The PEO side chains were not directly attached to the backbone but via polymethacrylate spacers, thus locating the PEO chains a distance away from the charged units of the backbone. The cationic brush-on-brush polyelectrolytes with high density of PEO chains showed a strong affinity to silica surfaces, provided the backbone charge density was high enough. The adsorption of these polymers was studied by QCM-D giving very high sensed mass, 20 mg/m2. It was shown by direct force measurements that protective surface layers were formed by the novel polyelectrolytes, generating strongly repulsive steric forces, which provided an effective barrier against flocculation. The adsorbed layer was sufficiently robust to withstand sliding experiments under a pressure of up to 35 MPa. The friction force in water was very low, and the lubrication was characterized by a friction coefficient in the range of 0.02-0.06. 相似文献
67.
In this article, we introduce and investigate the concept of multivalued hybrid mappings in CAT(0) spaces by using the concept of quasilinearization. Also, we present a new iterative algorithm involving products of Moreau-Yosida resolvents for finding a common element of the set of minimizers of a finite family of convex functions and a common fixed point of two multivalued hybrid mappings in CAT(0) spaces. 相似文献
68.
Sakineh Asghari Mohammad Qandalee Zahra Naderi Zahra Sobhaninia 《Molecular diversity》2010,14(3):569-574
The addition of acetylenic esters to aromatic amines such as 2-amino benzophenone derivatives in the presence of triphenylphosphine
leads to highly functionalized phosphoranes, which undergo an intramolecular Wittig reaction following oxidation to produce
quinoline derivatives. 相似文献
69.
Recent progress in electrospun nanofibers: Reinforcement effect and mechanical performance 下载免费PDF全文
Soheila Mohammadzadehmoghadam Yu Dong Ian Jeffery Davies 《Journal of Polymer Science.Polymer Physics》2015,53(17):1171-1212
Composite materials are becoming increasingly important as structural materials for aeronautical and space engineering, naval, automotive, and civil engineering, sporting goods, and other consumer products. Fiber‐based reinforcement represents one of the most effective manufacturing strategies for enhancing the mechanical strength and other properties of composite materials. Electrospinning has gained widespread interest in the last two decades because of its ability to fabricate continuous ultrafine nanofibers with unique characteristics. The impact of electrospinning on fiber synthesis and processing, characterization, and applications in drug delivery, nanofiltration, tissue scaffolding, and electronics has been extensively studied in the past. In this article, the authors have focused on a comprehensive review of the mechanical performance and properties of electrospun nanofibers as potential reinforcements as well as their advanced nanocomposites. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1171–1212 相似文献
70.
Palladium nanoparticles supported on polymeric N‐heterocyclic carbene grafted silica as an efficient organic–inorganic hybrid catalyst is introduced. Pd0 nanoparticle formation, which is stabilized by the polymeric N‐heterocyclic carbene ligands and ionic liquid units, was confirmed using X‐ray photoelectron spectroscopy. Scanning electron microscopy images showed microparticles of modified silica while transmission electron microscopy images displayed a fine distribution of Pd nanoparticles. The modified structure was applied successfully in biaryl formation via Suzuki and Stille coupling reactions. Various biaryls were generated through the reaction of phenylboronic acid or tetraphenyltin with a variety of haloarenes via cross‐coupling reactions. This catalyst showed promising activity after being recycled several times. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献