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131.
Homayon Ahmad Panahi Alireza Feizbakhsh Rozita Abdolahi Fard Elham Moniri 《毒物与环境化学》2013,95(8):1279-1289
Quantitative analysis of cadmium in environmental samples was achieved with a polymeric sorbent synthesized by copolymerization of N,N-dimethylacrylamide and allyl glycidyl ether/iminodiacetic acid as chelating monomers with N,N′-methylenebisacrylamide as cross-linker. The polymer was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis, and scanning electron microscopy. The sorption capacity of the functionalized sorbent was 70 mg g?1. The equilibrium sorption data of Cd(II) on polymeric sorbent were analyzed using Langmuir, Freundlich, Temkin, and Redlich–Peterson models. Based on equilibrium adsorption data, the constants at pH 4.2 and 20 °C were determined for the first three as 0.33 (L mg?1), 17.5 (mg g?1) (L mg?1)1/n, and 12.9 (J mol?1). Recovery of 94% of the metal ion was obtained with 0.5 mol L?1 nitric acid as an eluting agent. 相似文献
132.
Ghorbani Amir Mousazadeh Hossein Taheri Fatemeh Ehteshammajd Shaghayegh Azadi Hossein Yazdanpanah Masoud Khajehshahkohi Alireza Tanaskovik Vjekoslav Van Passel Steven 《Environment, Development and Sustainability》2021,23(8):11792-11817
Environment, Development and Sustainability - This study is an attempt to develop ecotourism in Nehbandan County, in the South Khorasan Province, Iran, by representing unknown areas that have... 相似文献
133.
Alireza Bahadori Hari B. Vuthaluru 《Journal of Loss Prevention in the Process Industries》2010,23(2):367-372
Filling losses in tanks due to the expansion of the liquid into the tank and the vapors that are forced out of the tank are generally called displacement losses. Restrictions on vaporization loss of petroleum products give added emphasis to the accurate prediction of vapor pressure and hydrocarbon losses for petroleum products. In this work, firstly, a simple-to-use correlation is developed to estimate the true vapor pressure of liquefied petroleum gas (LPG) and natural gasoline as a function of Reid Vapor pressure (RVP) and temperature as well as the vapor pressure of different mixtures of propane and butane are correlated as a function of ambient air temperature and propane volume percent. Secondly, the filling losses from storage containers are estimated in percentage of liquid pumped in tanks as a function of working pressure and vapor pressure at liquid temperature. The study showed the proposed method to be in good agreement with the available reliable data in the literature. The average absolute deviation between reported data and the proposed correlation is less than 2%. The proposed simple-to-use approach can be of significant practical value for the process engineers and scientists to have a quick check on the prediction of the displacement losses from storage containers as well as for rapid estimation of vapor pressure of LPG and natural gasoline. 相似文献
134.
Fatemeh Bateni Sima Fakheran Alireza Soffianian 《Environmental monitoring and assessment》2013,185(12):10511-10519
Water quality of rivers is strongly influenced by landscape characteristics of their watershed, including land use /cover types, and their spatial configuration. This research evaluates the effects of land cover changes on the water quality of the Zayandehroud River, which is the most important river in the center of Iran. The main goal of this study was to quantify the change in rangelands, forests, and bare lands in the Zayandehroud river basin, which suffered intense human interference, in a period of 11 years (1997–2008), and to evaluate how landscape patterns (including the number of patches, edge density, percentage of rangelands, forests, and bare lands) influence on the 14 water quality indices (including BOD5, EC, NO3, P, and TDS) measured in 10 stations along the river. Results showed that from 1997 to 2008, bare lands increased from 5.8 to 20 %, while rangelands decreased from 70 to 55 % in the whole basin. The results indicated that water quality was significantly correlated with both the proportions and configuration of rangeland and bare land areas. The total edge (TE) of rangeland area had positive effects on water quality, especially on BOD5 and EC. Percentage of landscape (PLAND) and largest patch index (LPI) metrics of rangeland had positive effect on decreasing nutrient (NO3, PO4). The results showed that water quality was more likely degraded when there was high edge density (ED) of bare lands. Results of this study also revealed that degradation of rangeland lead to the degradation of water quality. Finding of this study highlights the importance of rangeland conservation in water quality management at landscape scale. 相似文献
135.
Alireza Ashori 《Journal of Polymers and the Environment》2010,18(1):65-70
Hybrid composites of thermoplastic biofiber reinforced with waste newspaper fiber (NF) and poplar wood flour (WF) were prepared.
The weight ratio of the lignocellulosic materials to polymer was 30:70 (w:w). Polypropylene (PP) and maleic anhydride grafted
polypropylene (MAPP) were also used as the polymer matrix and coupling agent, respectively. The mechanical properties, morphology
and thermal properties were investigated. The obtained results showed that tensile and flexural modulus of the composites
were significantly enhanced with addition of biofibers in both types (fiber and flour), as compared with pure PP. However,
the increasing in WF content substantially reduced the tensile, flexural and impact modulus, but improved the thermal stability.
This effect is explained by variations in fiber morphological properties and thermal degradation. Increasing fiber aspect
ratio improved mechanical properties. The effect of fiber size on impact was minimal compared to the effects of fiber content.
Scanning electron microscopy has shown that the composite, with coupling agent, promotes better fiber–matrix interaction.
The largest improvement on the thermal stability of hybrid composites was achieved when WF was added more. In all cases, the
degradation temperatures shifted to higher values after addition of MAPP. This work clearly showed that biofiber materials
in both forms of fiber and flour could be effectively used as reinforcing elements in thermoplastic PP matrix. 相似文献
136.
Effects of Waste Paper Sludge on the Physico-Mechanical Properties of High Density Polyethylene/Wood Flour Composites 总被引:1,自引:0,他引:1
Yahya Hamzeh Alireza Ashori Babak Mirzaei 《Journal of Polymers and the Environment》2011,19(1):120-124
The objective of this work was to determine some physical and mechanical properties of the high density polyethylene (HDPE)
composites reinforced with various mixtures of the paper sludge and the wood flour, and to evaluate the coupling agent performance.
The waste sludge materials originating from two different sources including paper making waste water treatment sludge (PS)
and ink-eliminated sludge (IES) were characterized in terms of physico-chemical properties. In the experiment, four levels
of paper sludge (20, 30, 40 and 60 wt%), three levels of wood flour (20, 40 and 60 wt%), and two levels of coupling agent
(MAPE) content (2 and 3 wt%) were used. The flexural properties of the composites were positively affected by the addition
of the sludge. Especially, tensile modulus improved with the increase of paper sludge content. With the addition of MAPE,
flexural properties improved considerably compared with control specimens (without any coupling agent). The results showed
that the water absorption (WA) and thickness swelling (TS) values of the samples decreased considerably with increasing sludge
content in the composite, while they increased with increasing wood flour content. It is to be noted that with incorporation
of MAPE in the composite formulation, the compatibility between the wood flour and HDPE was enhanced through esterification,
which reduced the WA and TS and improved the mechanical properties. Composites made with IES exhibited superior physico-mechanical
properties compared with the PS filled composites. Overall results suggest that the waste paper sludge materials were capable
of serving as feasible reinforcing fillers for thermoplastic polymer composites. 相似文献
137.
Mazaher Moeinaddini Abbas Esmaili Sari Alireza Riyahi bakhtiari Andrew Yiu-Chung Chan Seyed Mohammad Taghavi Darryl Hawker Des Connell 《Environmental science and pollution research international》2014,21(12):7757-7772
The vertical concentration profiles and source contributions of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in respirable particle samples (PM4) collected at 10, 100, 200 and 300-m altitude from the Milad Tower of Tehran, Iran during fall and winter were investigated. The average concentrations of total PAHs and total n-alkanes were 16.7 and 591 ng/m3, respectively. The positive matrix factorization (PMF) model was applied to the chemical composition and wind data to apportion the contributing sources. The five PAH source factors identified were: ‘diesel’ (56.3 % of total PAHs on average), ‘gasoline’ (15.5 %), ‘wood combustion, and incineration’ (13 %), ‘industry’ (9.2 %), and ‘road soil particle’ (6.0 %). The four n-alkane source factors identified were: ‘petrogenic’ (65 % of total n-alkanes on average), ‘mixture of petrogenic and biomass burning’ (15 %), ‘mixture of biogenic and fossil fuel’ (11.5 %), and ‘biogenic’ (8.5 %). Source contributions by wind sector were also estimated based on the wind sector factor loadings from PMF analysis. Directional dependence of sources was investigated using the conditional probability function (CPF) and directional relative strength (DRS) methods. The calm wind period was found to contribute to 4.4 % of total PAHs and 5.0 % of total n-alkanes on average. Highest average concentrations of PAHs and n-alkanes were found in the 10 and 100 m samples, reflecting the importance of contributions from local sources. Higher average concentrations in the 300 m samples compared to those in the 200 m samples may indicate contributions from long-range transport. The vertical profiles of source factors indicate the gasoline and road soil particle-associated PAHs, and the mixture from biogenic and fossil fuel source-associated n-alkanes were mostly from local emissions. The smaller average contribution of diesel-associated PAHs in the lower altitude samples also indicates that the restriction of diesel-fueled vehicle use in the central area of Tehran has been effective in reducing the PAHs concentration. 相似文献
138.
Alireza A. Shamshirsaz Ramen H. Chmait Julien Stirnemann Mounira A. Habli Anthony Johnson Kamran Hessami Shayan Mostafaei Ahmed A. Nassr Roopali V. Donepudi Magdalena Sanz Cortes Jimmy Espinoza Eyal Krispin Michael A. Belfort 《黑龙江环境通报》2023,43(1):72-83
This meta-analysis aims to compare the perinatal outcome of twin-twin transfusion syndrome (TTTS) pregnancies undergoing selective versus vascular equator (Solomon) fetoscopic laser photocoagulation (FLP). We performed a systematic search in PubMed and Web of Science from inception up to 25 July 2021. Studies comparing the Solomon and selective techniques of FLP for treatment of TTTS pregnancies were eligible. Random-effects or fixed-effect models were used to pool standardized mean differences (SMD) and log odds ratio. Seven studies with a total of 1664 TTTS pregnancies (n = 671 undergoing Solomon and n = 993 selective techniques) were included. As compared to the selective FLP, Solomon was associated with a lower risk of recurrent TTTS compared to the selective technique (Log odds ratio [OR]: −1.167; 95% credible interval [CrI]: −2.01, −0.33; p = 0.021; I2: 67%). In addition, Solomon was significantly associated with a higher risk of placental abruption than the selective technique (Log [OR]: 1.44; 95% CrI: 0.45, 2.47; p = 0.012; I2: 0.0%). Furthermore, a trend for the higher risk of preterm premature rupture of membranes was observed among those undergoing Solomon (Log [OR]: 0.581; 95% CrI: −0.43, 1.49; p = 0.131; I2: 17%). As compared to selective FLP, the Solomon technique for TTTS pregnancies is associated with a significantly lower recurrence of TTTS; however, it significantly increases the risk of placental abruption. 相似文献
139.
Talaei Aisona Ashori Alireza Heydari Vahid 《Journal of Polymers and the Environment》2022,30(10):4263-4270
Journal of Polymers and the Environment - This study aims to make environment-friendly plywood panels acceptable in terms of both mechanical and physical properties using chitosan as a natural... 相似文献
140.
Arshadi Mahdokht Esmaeili Alireza Yaghmaei Soheila Arab Bahareh 《Journal of Material Cycles and Waste Management》2022,24(1):83-96
Journal of Material Cycles and Waste Management - In this research, Zn, Ni, and Cu recovery from mobile phone printed circuit boards was investigated. The initial pH and pulp density using... 相似文献