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Effects of silver nanoparticle size,concentration and coating on soil quality as indicated by arylsulfatase and sulfite oxidase activities

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Pedosphere 2022年第5期32卷 733-743页

作者： Yutong XUE Prashank MISHRA frieda eivazi Zahra AFRASIABI Environmental Studies Concentration Soka University of AmericaAliso Viejo CA 92656(USA) Nicholas School of the Environment Duke UniversityDurham NC 27707(USA) Department of Agriculture and Environmental Sciences Lincoln UniversityJeferson City MO 6510l(USA)

Recently, the nanotechnology industry has seen a growing interest in integrating silver nanoparticles(AgNPs) into agricultural products, which increases soil exposure to these particles. This demands an investigation into the effect of AgNPs on soil health. Changes in soil enzyme activities upon exposure to AgNPs can serve as early indicators of any adverse effects that these particles may have on soil quality. This study aimed to determine the effects of AgNP size, concentration, coating, and exposure time on the activities of two sulfur cycle enzymes, arylsulfatase and sulfite oxidase. To investigate the sensitivity of soil enzyme activity to AgNP contamination, silt loam soil samples were treated with 30, 80, and 200 nm-sized AgNPs coated with citrate, lipoic acid,and polyvinylpyrrolidone at 1, 10, and 100 mg Ag kgsoil, with the changes in enzyme activities monitored at 3 h, 3 d, and 30 d after treatment. For comparison, the effects of silver(Ag) ions on the enzyme activities were studied under similar treatment conditions. For most of the concentrations tested, the inhibitory effects of AgNPs on different enzymes differed, with a much stronger effect on sulfite oxidase activity than on arylsulfatase activity. The AgNP concentration and exposure time played much important roles than coating type and particle size in the effects of AgNPs on soil enzyme activities.

关键词： citrate lipoic acid polyvinylpyrrolidone soil health sulfur cycle enzyme

Greenhouse gases fluxes and soil thermal properties in a pasture in central Missouri

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Journal of Environmental Sciences 2010年第7期22卷 1029-1039页

作者： Nsalambi Vakanda Nkongolo Shane Johnson Kent Schmidt frieda eivazi Department of Agriculture and Environmental Sciences College of Agriculture and Natural Science Lincoln University Harvard Forest Faculty of Arts and Sciences Harvard University

Fluctuations of greenhouse gases emissions and soil properties occur at short spatial and temporal scales, however, results are often reported for larger scales studies. We monitored CO2, CH4, and N2O fluxes and soil temperature （T）, thermal conductivity （K）, resistivity （R） and thermal diffusivity （D） from 2004 to 2006 in a pasture. Soil air samples for determination of CO2, CH4 and N2O concentrations were collected from static and vented chambers and analyzed within two hours of collection with a gas chromatograph. T, K, R and D were measured in-situ using a KD2 probe. Soil samples were also taken for measurements of soil chemical and physical properties. The pasture acted as a sink in 2004, a source in 2005 and again a sink of CH4 in 2006. CO2 and CH4 were highest, but N2O as well as T, K and D were lowest in 2004. Only K was correlated with C02 in 2004 while T correlated with both N2O （r = 0.76, p = 0.0001） and CO2 （r = 0.88, p = 0.0001） in 2005. In 2006, all gases fluxes were significantly correlated with T, K and R when the data for the entire year were considered. However, an in-depth examination of the data revealed the existence of month-to-month shifts, lack of correlation and differing spatial structures. These results stress the need for further studies on the relationship between soil properties and gases fluxes. K and R offer a promise as potential controlling factors for greenhouse gases fluxes in this pasture.

关键词： greenhouse gases soil thermal properties fluxes

Graphene quantum dot modified glassy carbon electrode for the determination of doxorubicin hydrochloride in human plasma

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Journal of Pharmaceutical Analysis 2016年第4期6卷 235-241页

作者： Nastaran Hashemzadeh Mohammad Hasanzadeh Nasrin Shadjou Jamal eivazi-Ziaei Maryam Khoubnasabjafari Abolghasem Jouyban Hematology-Oncology Research Center Tabriz University of Medical Sciences Faculty of Pharmacy Students'Research CommitteeTabriz University of Medical Sciences Drug Applied Research Center Tabriz University of Medical Sciences Pharmaceutical Analysis Research Center and Faculty of Pharmacy Tabriz University of Medical Sciences Department of Nanochemistry Nano Technology Research Center and Faculty of Chemistry Urmia University Tuberculosis and Lung Disease Research Center Tabriz University of Medical Sciences

Low toxic graphene quantum dot（GQD） was synthesized by pyrolyzing citric acid in alkaline solution and characterized by ultraviolet-visible（UV-vis） spectroscopy,X-ray diffraction（XRD）,atomic force microscopy（AFM）,spectrofluorimetery and dynamic light scattering（DLS） *** was used for electrode modification and electro-oxidation of doxorubicin（DOX） at low potential.A substantial decrease in the overvoltage（- 0.56 V） of the DOX oxidation reaction（compared to ordinary electrodes） was observed using GQD as coating of glassy carbon electrode（GCE）.Differential pulse voltammetry was used to evaluate the analytical performance of DOX in the presence of phosphate buffer solution（pH 4.0） and good limit of detection was obtained by the proposed *** ability of GQD to promote the DOX electron-transfer reaction suggests great promise for its application as an electrochemical sensor.

关键词： Doxorubicin hydrochloride Graphene quantum dot Nanotechnology Electrochemical sensor

Evaluation Forage Clipping Stages and Different Levels of Nitrogen on Grain and Forage Yields of TRITICALE (×TRITICOSECALE WITTMACK)

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American Journal of Plant Sciences 2014年第15期5卷 2199-2206页

作者： Mohsen Niazkhani Abdolmajid Khorshid Alireza eivazi Agricultural Research Center of West Azerbaijan Province Urmia Iran Department of Plant Breeding Zanjan University Zanjan Iran

In order to reach suitable forage clipping and estimate nitrogen fertilizer to most economical proficiency, an experiment was carried out at Saatlo Station in 2008-2009 seasons. A factorial experiment was done based on the randomized complete blocks design with 4 replications. The first factor was three levels of clipping stages including non-clipping, clipping at tillering and booting stages. Different levels of nitrogen fertilizer including 0, 40, 80, 120 and 160 kg/ha were arranged at the second factor. Results showed that non-clipping and clipping at booting stage with 610.5 and 203.1 g/m2 had the most and the lowest grain yield, respectively. The highest economical proficiency (3743.06 $/ha) resulted with using 80 kg/ha nitrogen fertilizer and non-clipping. With considering both forage and grain yield, it is necessary that the clipping should be done at tillering stage with using of 120 kg/ha nitrogen fertilizer (3336.56 $/ha). At regression of economical proficiency traits of grain yield, straw and total dry matter remained at the final model. Economical proficiency had the significant positive correlation with spike per square meter (0.87**), grain yield (0.64**), total dry matter (0.65**), plant height (0.52**) and 1000-kernal weight (0.54**).

关键词： Forage Yield Grain Yield Triticale

Kinetic Analysis of Isothermal Leaching of Zinc from Zinc Plant Residue

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International Journal of Nonferrous Metallurgy 2013年第1期2卷 10-20页

作者： Ali Reza eivazi Hollagh Eskandar Keshavarz Alamdari Davooud Moradkhani Ali Akbar Salardini Faculty of Engineering Zanjan University Zanjan Iran Materials and Energy Research Center Tehran Iran. Mining & Metallurgical Engineering Amirkabir University of Technology Tehran Iran Mining & Metallurgical Engineering Amirkabir University of Technology Tehran Iran&Research Center for Materials and Mining Industries Technology Amirkabir University of Technology Tehran Iran

The sulfuric acid leaching of zinc plant residues was studied in an attempt to find a suitable hydrometallurgical method for zinc recovery. The parameters evaluated consist of reaction time, Solid-to-liquid-ratio, reaction temperature, agitation rate and pH. The results of kinetic analysis of the leaching data under various experimental conditions indicated that there is a reaction controlled by the solution transport of protons through the porous product layer with activation energy of about 1 kJ/mol for different constant solid to liquid ratios. Based on the shrinking core model (SCM), the following semiempirical rate equation was established:1-3(1-a)2/3+2(1-a)=0.001187×[H+]0.016×[(S/L)]-1.34×exp(-1/RT) ×t. On the other hand, activation energy was obtained from a model-free method using isothermal measurements. Values for activation energy were calculated as a result of the conversion function with an average of 2.9 kJ/mol. This value is close to that determined previously, using shrinking core model (SCM).

关键词： Zinc Hydrometallurgy Kinetic Model Zinc Plant Residue Model-Free Method

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头颈部血管畸形和血管瘤治疗进展

中国口腔颌面外科杂志 2013年第3期 191-191页

作者： eivazi B Werner JA

该文旨在通过对头颈部血管畸形和血管瘤的文献进行回顾分析,提出头颈部血管畸形治疗策略的改善,强化多学科联合治疗及国际交流的重要性。尽管"汉堡分类"已经被国际普遍接受,但是在一些文献中仍可以见到关于"血管瘤"的不恰当使用。目前,... 详细信息

该文旨在通过对头颈部血管畸形和血管瘤的文献进行回顾分析,提出头颈部血管畸形治疗策略的改善,强化多学科联合治疗及国际交流的重要性。尽管"汉堡分类"已经被国际普遍接受,但是在一些文献中仍可以见到关于"血管瘤"的不恰当使用。目前,普萘洛尔在血管瘤治疗方面已经取得了显著效果,局部应用β受体阻滞剂治疗血管瘤的报道越来越

关键词：血管瘤 β受体阻滞剂血管肿瘤 β型肾上腺素能受体森林阻火剂畸形头颈部血管

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头颈部血管瘤及脉管畸形的最新资料

中国口腔颌面外科杂志 2009年第4期7卷 325-325页

作者： eivazi B Ardelean M Bumler W

Update on hemangiomas and vascular malformations of the head and neck. eivazi B, Ardelean M, Baumler W et al. Eur Arch Otorhinolaryngol, 2009, 266（2）：187-197.

关键词：头颈部血管瘤脉管畸形诊断评价