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151.
The therapeutic properties of tin nanoparticles have been proved in recent years. One of their probable effects is anti-anemia. In this study, tin nanoparticles were synthesized and characterized in aqueous medium using Ziziphora clinopodioides Lam leaf aqueous extract as the reducing and stabilizing agent. We also assessed the antihemolytic anemia potential of tin nanoparticles (SnNPs) in an animal model of hemolytic anemia. Tin nanoparticles were characterized using many techniques including Fourier transform-infrared and UV-visible spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectrometry, and field emission-scanning electron microscopy (FE-SEM). FE-SEM images showed a uniform spherical morphology in size of 18.12 nm for the green synthesized nanoparticles. According to XRD analysis, SnNPs crystal size was17.94 nm. SnNPs had low cell viability dose-dependently against human umbilical vein endothelial cell line. in vivo design, induction of hemolytic anemia was done by phenylhydrazine in 40 mice. Tin nanoparticles significantly (p ≤ 0.01) reduced the weight and volume of liver and spleen and the concentration of pro-inflammatory cytokines, and increased the body weight, anti-inflammatory cytokines concentration, total platelet, WBC, neutrophil, lymphocyte, eosinophil, monocyte, and basophil counts, and red blood cell parameters compared to the untreated mice. For the biochemical parameters, SnNPs significantly (p ≤ 0.01) increased the concentrations of GPx, CAT, and SOD in serum, liver, and spleen and decreased the concentration of GR in serum, liver, and spleen, and also erythropoietin, ferritin, and ferrous in serum as compared to the anemic mice. The 2,2-diphenyl-1-picrylhydrazyl test showed similar antioxidant activities for SnNPs and butylated hydroxytoluene. The results demonstrate the excellent antihemolytic anemia, hematoprotective, cytotoxicity, and antioxidant potentials of SnNPs compared to other experimental groups.  相似文献   
152.
A series of new boron‐bridged [1]ferrocenophanes ([1]FCPs) was prepared by salt‐metathesis reactions between enantiomerically pure dilithioferrocenes and amino(dichloro)boranes (Et2NBCl2, iPr2NBCl2, or tBu(Me3Si)NBCl2). The dilithioferrocenes were prepared in situ by lithium–bromine exchange from the respective planar‐chiral dibromides (Sp,Sp)‐[1‐Br‐2‐(HR2C)H3C5]2Fe (R=Me or Et). In most of the cases, mixtures of the targeted [1]FCPs 4 and the unwanted 1,1′‐bis(boryl)ferrocenes 5 were formed. The product ratio depends on the bulkiness of the amino group, the speed of addition of the amino(dichloro)borane, the alkyl group on Cp rings, and in particular on the reaction temperature. The formation of strained [1]FCPs is strongly favored by increased reaction temperatures. Secondly, CHEt2 groups at Cp rings favored the formation of the targeted [1]FCPs stronger than CHMe2 groups. These discoveries open up new possibilities to further suppress the formation of unwanted byproducts by a careful choice of the reaction temperature and through tailoring the bulkiness of CHR2 groups on ferrocene. Thermal ring‐opening polymerizations of selected boron‐bridged [1]FCPs gave metallopolymers with a Mw of 10 kDa (GPC).  相似文献   
153.
A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4-aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes, malononitrile and 3,5-dimethoxy phenol under reflux condition has been developed in aqueous Et OH media using Na2O-Al2O3-P2O5glass–ceramic system.  相似文献   
154.
Two new copper complexes [Cu(Hdpa)2(en)] (1) and [{Cu2(μ-na)4(CH3OH)2}·2CH3OH] (2) (where en is ethylene diamine, Hdpa is 2′-carboxy-[1,10-biphenyl]-2-carboxylate anion and na is 1-naphtalenecarboxylate) have been synthesized and their crystal structures were determined by X-ray crystallography. Complex 1 was prepared from the reaction of Cu(NO3)2·3H2O with ethylene diamine and 2,2′-biphenyldicarboxylic acid in a mixture of water and methanol and complex 2 was prepared from the reaction of CuSO4·5H2O with 1-naphtalenecarboxylic acid in methanol. The two complexes were characterized by IR, UV–vis, luminescence and elemental analysis. Moreover, complex 2 was characterized by EPR spectroscopy and thermogravimetric analysis. Complex 1 is a monomer and complex 2 is a dimer with a paddle-wheel structure; both structures are without precedent in the literature.  相似文献   
155.
The complexation reaction of phenylaza-15-crwon-5, 4- nitrobenzo- 15-crown-5, and benzo-15-crown-5 with Ag+, Tl+ and Pb2+ ions in methanol solution have been studied by a competitive potentiometric method. The Ag+/Ag electrode used both as an indicator and reference electrode in a concentration cell. The emf of cell monitored as the crown ethers concentration varies through the titration. The stoichiometry and stability constants of resulting complexes have been evaluated by MINIQUAD. The stoichiometry for all resulting complexes was 1:1. The stability of these metal ions with derivatives of 15-crown-5 are in order phenylaza-15-crown-5 > Benzo-15-crown-5 > 4-nitrobenzo-15-crown-5, and for the each used crown ethers are as Pb2+ > Ag+ > Tl+. The effect of the substituted group on the stability of resulting complexes was considered. The obtained results are novel and interesting.  相似文献   
156.
NiO nanoparticles with an average size of about 12 nm were easily prepared via the thermal decomposition of hexa(ammine)Ni(II) nitrate complex, [Ni(NH3)6](NO3)2, at low temperature of 250 °C. The product was characterized by thermal analysis (TGA/DTA), X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), UV-Vis spectroscopy, BET specific surface area measurement, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and magnetic measurement. The magnetic measurement revealed a small hysteresis loop at room temperature, confirming a superparamagnetic (weak ferromagnetic) nature of the synthesized NiO nanoparticles. Indeed, the NiO nanoparticles prepared by this method could be an appropriate semiconductor material due to the optical band gap of 3.35 eV which shows a red shift in comparison with the previous reports. This method is simple, fast, safe, low-cost and also suitable for industrial production of high purity NiO nanoparticles for applied purposes.  相似文献   
157.
A new electrochemical PNA hybridization biosensor for detection of a 15‐mer sequence unique to p53 using indigo carmine (IC) as an electrochemical detector is described in this work. This genosensor is based on the hybridization of target oligonucleotide with its complementary probe immobilized on the gold electrode by self‐assembled monolayer formation. Because this label is electroactive in acidic medium, the interaction between IC and short sequence of p53 is studied by differential pulse voltammety (DPV) in 0.1 M H2SO4. The results of electrochemical impedance spectroscopy and cyclic voltammetry in the solution of [Fe(CN)6]3?/4? shows no breakage in PNA‐DNA duplex. A decrease in the voltammetric peak currents of IC is observed upon hybridization of the probe with the target DNA. The influence of probe concentration on effective discrimination against non‐complementary oligonucleotides is investigated and a concentration of 10?7 M is selected. The diagnostic performance of the PNA sensor is described and the detection limit is found to be 4.31×10?12 M.  相似文献   
158.
The solution polymerization of ethylene using rac-Et(Ind)2ZrCl2/MAO and (Dimethylsilyl(tert-butylamido)(tetramethyl- cyclopentadienyl)titanium Dichloride)(CGC-Ti)/MAO was studied in a semi-batch reactor at 120 °C under different monomer pressures and catalyst concentrations. The kinetics of ethylene polymerization with rac-Et(Ind)2ZrCl2/MAO can be described with first order reactions for polymerization and catalyst deactivation. When (CGC-Ti)/MAO is used, however, second order kinetics are observed for catalyst decay and the order of polymerization changes from 2 to 1 with increasing ethylene pressure.  相似文献   
159.
A model low-fat salad dressing including salep as thickening agent was prepared. In order to obtain an stable salad dressing, different variables each one at three levels like salep content (0.5, 2.0, and 3.5% w/w), oil volume fraction (7.50, 16.25, and 25.00% w/w), pH (3, 5, and 7), salt concentration (0.3, 0.9, and 1.5% w/w), and egg yolk content (2, 4, and 6% w/w) were chosen and their effect on the creaming index of salad dressing was studied. It was observed that samples with highest salep content at pH 3 were the most stable during storage time (15 days). The microstructure of some samples was considered. Rheological measurements were performed for stable samples. Oil fraction and salt content increased zero shear viscosity and G′ modulus of samples.   相似文献   
160.
In this work, synergistic flotation of U(VI)-alizarin complex at the presence of some diamine compounds was firstly investigated by the spectrophotometric method. The flotation process was carried out on aliquots of 100 ml of U(VI) solutions containing alizarin and the diamine at pH of 5.00 using n-heptane. The floated layer was then dissolved in acetonitrile and its absorbance was measured. Since the synergistic effect of 4,4′-diaminophenylmethane (dapm) was much more than the others, it was used for the determination of U(VI) by this method. Beer's law was obeyed (λmax = 591 nm) in the range of 5 × 10−7 to 1 × 10−5 mol l−1 with the apparent molar absorptivity of 1.12 × 106 l mol−1 cm−1, and a correlation coefficient of 0.9991. The detection limit (n = 7) was 1 × 10−7 mol l−1, and the R.S.D. (n = 7) obtained for 4 × 10−6 mol l−1 of U(VI) was 2.23%. Except that only a few analogous cations, which could be masked by EDTA, no interference was observed at the presence of various conventional ions, even at high concentrations. The reliability and applicability of the method were confirmed using some geological standard reference materials and spiked synthetic water samples, respectively.  相似文献   
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