A low cost-effective and simple synthesis method was adopted to acquire three-dimensional flower-like structure Fe3O4/c that has large specific area, suitable pore structure and sufficient saturation magnetism. The ob...
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A low cost-effective and simple synthesis method was adopted to acquire three-dimensional flower-like structure Fe3O4/c that has large specific area, suitable pore structure and sufficient saturation magnetism. The obtained Fe3O4/c exhibits outstanding preconcentration ability and was applied to extracting non-steroidal anti-inflammatory drugs from complex environmental and biological samples. The parameters of magnetic solid-phase extraction were optimized by univariate and multivariate methods (Box-Behnken design). The high degree of linearity from 2.5 to 1000.0 ng mL(-1) (R-2 >= 0.9976), the limits of detection from 0.25 to 0.5 ng mL(- 1) (S/N =3), and the limits of quantitation from 1.0 to 2.0 ng mL(- 1) (S/N =10) were yielded by adopting this novel method after the optimization. Moreover, the recoveries of non-steroidal anti-inflammatory drugs from 89.6 to 107.0% were acquired in spiked plasma, urine and lake samples. In addition, the adsorption of non-steroidal anti-inflammatory drugs on Fe3O4/c was explored by adsorption isotherms and kinetic studies. Furthermore, the adsorption mechanism for non-steroidal anti-inflammatory drugs by Fe3O4/c was proposed, which was hydrogen bonding and - interaction between non-steroidal anti-inflammatory drugs and Fe3O4/c.
AIM To detect infection rate of GBV-c/HGV inhepatitis c patients,to determine the methodsof higher sensitivity and the primers of higherefficiency for GBV-c/HGV RNA detection and tostudy the dominant subtype and mutat...
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AIM To detect infection rate of GBV-c/HGV inhepatitis c patients,to determine the methodsof higher sensitivity and the primers of higherefficiency for GBV-c/HGV RNA detection and tostudy the dominant subtype and mutation ofGBV-c/*** Quantitative RT-PcR for detectionpf HcV RNA concentration in serum samples,RT-nested PcR with two sets of primers fordetection of GBV-c RNA,RT-PcR ELISA with twosets of primers for detection of HGV RNA,nucleotide sequence and putative amino acidsequence *** The positive rates of GBV-c RNA atthe 5’-NcR and NS3 region in 211 serums amplesfrom the patients with HcV infection were 31.8%and 22.8% *** positive rates ofHGV RNA at the 5’-NcR and NS5 region in thesame samples were 47.9% and 31.8%*** total positive rate of GBV-c/HGV RNA was as high as 55.5%.HcV copynumbers in the patients without GBV-c/ HGVcoinfection were statistically higher than that inthe patients with GBV-c/ HGV coinfection(P<0.01).Frequent mutation of nucleotideresidue was present in the *** mutation was found in twosamples with GBV-c NS3 region *** nucleotide sequences fromamplification products showed higher homologyto HGV genome than to GBV-c genome even though part of the sequences were amplifiedwith GBV-c *** A high frequency of GBV-c/ HGV coinfection existed in the hepatitis c patients. RT-PcR ELISA was more sensitive than RT-nested PcR for detection of GBV-c/ HGV RNA. The primers derived from the 5 -NcR was more efficient than those derived from the NS3 and NS5 regions. A reverse relationship was found to exist between HcV RNA concentration and GBV-c/ HGV infection frequency. HGV was the dominant subtype of the virus in the local area. The major mutations of GBV-c/ HGV genomes were random mutation of nucleotide residue.
A phytochemical study of the cHcl3 extract of the dried unripe fruits of Evodia rutaecarpa (Juss.) Benth. (Rutaceae) resulted in the isolation of three new alkaloids, evollionines A-c (1-3, resp.), together with two k...
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A phytochemical study of the cHcl3 extract of the dried unripe fruits of Evodia rutaecarpa (Juss.) Benth. (Rutaceae) resulted in the isolation of three new alkaloids, evollionines A-c (1-3, resp.), together with two known compounds, evodianinine and wuzhuyumide I. The structures of the new compounds were elucidated on the basis of detailed spectroscopic evidence and confirmed in the case of compound 1 by single-crystal X-ray analysis.
A series of Ag-0@c/SiO2 adsorbents were prepared using rice husk-based c/SiO2 as supports and applied to capture iodine gas. The results demonstrated that 50%Ag-0@c/SiO2 reached a record high iodine adsorption capacit...
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A series of Ag-0@c/SiO2 adsorbents were prepared using rice husk-based c/SiO2 as supports and applied to capture iodine gas. The results demonstrated that 50%Ag-0@c/SiO2 reached a record high iodine adsorption capacity (788 +/- 25 mg/g) due to the synergistic effect between c/SiO2 supports and Ag-0 sites. The adsorption data of Ag-0@c/SiO2 can be better fitted with the pseudo first order and Langmuir models. The iodine adsorption process included the physical and chemical adsorption. The adsorption mechanism was that Ag-0 reacted with I-2 to form AgI. Owing to the excellent adsorption capacity, Ag-0@c/SiO2 derived from rice husk could be promising iodine gas adsorbents.
This paper presents the results of irrigated rotation experiment, conducted in the North West Frontier Province (NWFP), Pakistan, during 1999-2002 to evaluate effects of residues retention, fertilizer N and legumes in...
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This paper presents the results of irrigated rotation experiment, conducted in the North West Frontier Province (NWFP), Pakistan, during 1999-2002 to evaluate effects of residues retention, fertilizer N and legumes in crop rotation on yield of maize (Zea mays L.) and soil organic fertility. chickpea (cicer arietinum Q and wheat (Triticum aestivum Q were grown in the winters and mungbean (Vigna radiata) and maize in the summers. Immediately after grain harvest, above-ground residues of all crops were either completely removed (-residue), or spread across the plots and incorporated by chisel plough by disc harrow and rotavator (+residue). Fertlizer N rates were nil or 120 kg ha(-1) for wheat and nil or 160 kg ha(-1) for maize. Our results indicated that post-harvest incorporation of crop residues significantly (p < 0.05) increased the grain and stover yields of maize during both 2000 and 2001. On average, grain yield was increased by 23.7% and stover yield by 26.7% due to residue incorporation. Residue retention also enhanced N uptake by 28.3% in grain and 45.1% in stover of maize. The soil N fertility was improved by 29.2% due to residue retention. The maize grain and stover yields also responded significantly to the previous legume (chickpea) compared with the previous cereal (wheat) treatment. The legume treatment boosted grain yield of maize by 112% and stover yield by 133% with 64.4% increase in soil N fertility. Similarly, fertilizer N applied to previous wheat showed considerable carry over effect on grain (8.9%) and stover (40.7%) yields of the following maize. Application of fertilizer N to current maize substantially increased grain yield of maize by 110%, stover yield by 167% and soil N fertility by 9.8% over the nil N fertilizer treatment. We concluded from these experiments that returning of crop residues, application of fertilizer N and involvement of legumes in crop rotation greatly improves the N economy of the cropping systems and enhances crop produc
Thermal shock resistance (TSR) and related damage mechanism of c/c-Sic-ZrSi2 composites produced via Si-Zr alloy melt infiltration was investigated using a newly-developed equipment at superior high temperatures up to...
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Thermal shock resistance (TSR) and related damage mechanism of c/c-Sic-ZrSi2 composites produced via Si-Zr alloy melt infiltration was investigated using a newly-developed equipment at superior high temperatures up to 2100 degrees c in an inert atmosphere. TSR was characterized by the residual strength and mass variation of the composites subjecting to thermal shock tests with different cycles and temperatures. Results indicated that TSR and damage of the composites were closely dependent on the testing cycles and especially temperatures. Strength of the composites was generally decreased with the increasing tested cycles. Slight strength reduction subjected to the low testing temperatures (< 1300 degrees c) were detected because almost no crack propagation occurred in the c-Sic-ZrSi2 matrix. At relatively higher temperatures (1300-1700 degrees c), thermal stress caused by temperature gradient and thermal expansion coefficient mismatch was greatly increased. consequently, matrix crack propagating into the intra fiber bundles and interfacial layers with much longer propagation paths were generated. Repeated thermal stress during cycled thermal shock tests weakened the interface bonding in the composites, and resulted in the delamination and interfacial debonding with obvious strength degradation. At ultrahigh temperatures (>= 1700 degrees c), matrix pores were produced due to ZrSi2 evaporation. combining effect by thermal stress and ZrSi2 evaporation caused severe damage to the composites with sharp strength reduction.
作者:
GOLDScHMIDT, ALaboratorio de Microanálisis
Departamento de Geología Facultad de Ciencias Físicas y Matemáticas Universidad de Chile Casilla 13518 Correo 21 Santiago Chile
The morphology and chemical composition of the evaporation products of the liquid phase and the c 3 S paste were studied by Microprobe (EPMA) and Scanning Flectron Microscope (SEM). Results that support those of previ...
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The morphology and chemical composition of the evaporation products of the liquid phase and the c 3 S paste were studied by Microprobe (EPMA) and Scanning Flectron Microscope (SEM). Results that support those of previous research were obtained, increasing these, since it was proved — by means of my research in a direct way, that morphologically and chemically speaking, products of c 3 S hydration and the ones obtained through slow evaporation of the liquid phase of the c 3 S water are different. chemically, in these products of evaporation, no correlation was found between the Si and ca, which appears to be an argument in favor of the topochemical hydration theory.
The rational design and synthesis of advanced electrode materials are significant for the applications of supercapacitors. Ferroferric oxide (Fe3O4), with its high theoretical capacitance is a renowned cathode materia...
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The rational design and synthesis of advanced electrode materials are significant for the applications of supercapacitors. Ferroferric oxide (Fe3O4), with its high theoretical capacitance is a renowned cathode material. Nevertheless, its low electronicconductivity and poor cycling stability during a long-term charge/discharge process limit its large-scale applications. In this work, the precise modulation of multiple components was reported to enhance electrochemical performance. The ternary heterostructures were fabricated by wrapping ultrathin nickel hydroxide (Ni(OH)2) nanosheets on the surfaces of Fe3O4 nanoparticles-loaded on sodium carboxymethyl cellulose (cMc)-derived porous carbon, named as c/ Fe3O4@Ni(OH)2. Due to the large specific surface area and excellent conductivity of cMc-derived porous carbon and the abundant reaction sites of Ni(OH)2 nanosheets, the optimized c/Fe3O4@Ni(OH)2-1.0 sample exhibited the highest specificcapacitance of 3072F g-1 at a current density of 0.5 A g-1. Furthermore, the assembled asymmetric supercapacitor (ASc) with activated carbon and c/Fe3O4@Ni(OH)2-1.0 as the negative and positive electrodes, respectively, showed an energy density of 123 W h kg-1 at 381 W kg-1, and a long-life stability with an excellent capacitance retention of 90.04 % after 10,000 cycles. The route for preparing composite electrode materials proposed in this work provides a reference for realizing highperformance energy storage devices.(c) 2022 Elsevier Inc. All rights reserved.
Aims To synthesize silver nanoparticles (AgNPs) with cell free extract of Acinetobacter sp. and evaluate antifungal activity against planktonic and biofilm of candida. Also, to study mechanism of antifungal action of ...
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Aims To synthesize silver nanoparticles (AgNPs) with cell free extract of Acinetobacter sp. and evaluate antifungal activity against planktonic and biofilm of candida. Also, to study mechanism of antifungal action of AgNPs. Methods and Result Acinetobacter spp were screened for synthesis of AgNPs. Physio-chemical parameters were optimized to obtained monodispersed nanoparticles. Optimized nanoparticles were characterized using spectroscopic, microscopic and diffraction techniques. Antifungal and biofilm disruption activity of AgNPs (10 +/- 5 nm) were investigated against c. albicans. Mechanism of antifungal activity of nanosilver was deduced by growth curve, reactive oxygen species generation, thiol interaction and microscopic analysis. Acinetobacter sp. GWRFH 45 gave maximum synthesis of AgNPs. At optimized condition monodispersed, spherical nanoparticles were obtained which were crystalline with negative surface charge. AgNPs exhibited antifungal activity against planktoniccells and biofilm of candida. AgNPs showed synergistic effect with amphotericin B as well as fluconazole against biofilm disruption. AgNPs were found to affect growth of candida, generate reactive oxygen species and disrupt cellular morphology. conclusions cell free extract of A. calcoaceticus GWRFH 45 has ability to synthesize AgNPs. AgNPs alone and in combination with drugs have potential to inhibit c. albicans. Significance and Impact of the Study This is the first report of bacteriogenic AgNPs used in combination with antifungal drugs against candida.
The cleavage of linkages of lignocellulose is important for its valorization. The linkage cleavage of cornstalk hydrolysis residue was investigated over catalysts (Ru/c + Mgcl2) in EtOAc/H2O solvents. The results show...
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The cleavage of linkages of lignocellulose is important for its valorization. The linkage cleavage of cornstalk hydrolysis residue was investigated over catalysts (Ru/c + Mgcl2) in EtOAc/H2O solvents. The results show that almost hydrogen bonds, c-c bonds, ether and ester bonds in the matrix of lignin and cellulose were broken, accompanying 80.6% of lignin and 98.5% of cellulose conversion, and obtaining 37.5% of aromatic monomers and 28.8% of lignin oligomers. In the reaction system, biphasic EtOAc/H2O solvents exhibited an effect on cleaving the intermolecular linkages between lignin and cellulose. Mgcl2 showed limited abilities of breaking the alpha-O-4 and beta-O-4 linkages in lignin and limited beta-1, 4-glycosidic and hydrogen bonds in cellulose were cleaved over Ru/ccatalyst. The cleavage of c-O linkages (alpha-O-4, beta-O-4, 4-O-5) and c-c bonds (alpha-beta, beta-5) in lignin were mainly dependent on Ru/ccatalyst. Much c-O and the stubborn c-c linkages of beta-5, beta-1 and 5-5 were significantly disrupted by the synergistic effect between Mgcl2 and Ru/c. However, Mgcl2 exhibited great contribution to breakage of beta-1, 4-glycosidic linkage, hydrogen bonds and sugar ring of cellulose. The linkage of beta-1, 4-glycosidic, hydrogen bonds and c-c in c5/c6 sugars were significantly broken. The increased yield of products was evidently due to the synergistic effect of Ru/ccombined with Mgcl2.
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