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71.
Majid Mahdieh Mojtaba Yazdani Shahla Mahdieh 《Environmental monitoring and assessment》2013,185(9):7877-7881
The major objective of this investigation was to evaluate the potential of scented geraniums, Pelargonium roseum, to uptake and accumulate heavy metals nickel (Ni), cadmium (Cd), or lead (Pb). For this, plants were grown in an artificial soil system and exposed to a range of metal concentrations over a 14-day treatment period. Then, metals from the entire biomass were extracted. The results showed that scented geranium plants accumulated in excess of 20,055 mg of Ni kg?1 dry weight (DW) of root and 10,889 mg of Ni kg?1 DW of shoot, and in excess of 86,566 mg of Pb kg?1 DW for roots and 4,416 mg of Pb kg?1 DW for shoots within 14 days. Also, the uptake and accumulation of cadmium in roots of scented geranium plants increased with the exposure at low (250, 500 mg?L?1) and medium level (750 mg?L?1) followed by a decline at the highest level (1,000 mg?L?1). The highest accumulation in roots (31,267 mg?kg?1 DW) was observed in 750 mg?L?1 cadmium treatment. In the shoots of scented geraniums, the highest amount of metal accumulation (1,957 mg?kg?1 DW) was detected at 750 and 1,000 mg?L?1 of cadmium in the culture solution. Finally, since the high concentrations of Ni or Pb accumulated in shoots of scented geranium has far exceeded 0.1 % DW and for Cd has far exceeded 0.01 % DW, P. roseum is a new hyperaccumulator species for these metals and can be used in phytoremediation industry. 相似文献
72.
Askarifard Majid Abbasianjahromi Hamidreza Sepehri Mehran Zeighami Ehsanollah 《Environment, Development and Sustainability》2021,23(8):11494-11524
Environment, Development and Sustainability - There is limited research that considers the sustainability aspect of the projects’ schedule. The present study proposes a model to cover this... 相似文献
73.
Since the 1950s, there has been a continuous increase in the number and coverage of protected areas (PAs) in Iran, and in total 253 PAs have been declared that cover 10.12?% of the country's area. This paper reviews literature addressing Iran's PAs, examines what is known about them, highlights the challenges and lessons learned, and identifies areas where more research is needed. The PA system in Iran is criticized because of (1) shortages of manpower, equipment, and financial resources; (2) de jure PAs that are often implemented as de facto reserves; (3) lack of national biodiversity indicators and objective monitoring processes; and (4) limited public participation and conflict between people over PAs. To improve, Iran's PAs system needs to be realistically supported by policies and planning instruments. In addition, the implementation of active management to restore habitat, increase education and awareness, shift practices towards the guidelines of international organizations, build capacity, and improve management and co-management by local communities needs to occur. 相似文献
74.
75.
Ali Jahani Jahangir Feghhi Majid F. Makhdoum Mahmoud Omid 《Journal of Environmental Planning and Management》2016,59(2):222-244
The purpose of this article is Artificial Neural Network (ANN) modeling using ecological and associated factors with forest degradation to predict the degradation of ecosystem, thereby enabling us to assess the environmental impacts of forest projects as an Environmental Decision Support System (EDSS). Results of the Multi-Layer Feed-Forward Network (MLFN), trained for Optimized Forest Degradation Model (OFDM), indicate that the performance of OFDM is more than other degradation models. Changes in forest management activities with higher value in sensitivity analysis help forest managers to decrease OFDM entity and environment impacts. The system is an intelligent EDSS, which allows the decision-maker to model criteria in forest degradation in order to reach and employ the optimal allocation plan. Considering results, multi criteria decision analysis (MCDA) approaches based on ANN, is an encouraging and robust method for solving MCDA problems. 相似文献
76.
Majid Soleimani Lope Tabil Satyanarayan Panigrahi Anthony Opoku 《Journal of Polymers and the Environment》2008,16(1):74-82
Recently, investigations have been conducted on the use of natural fibers as reinforcement in low-melting point thermoplastics
to improve mechanical properties of composites. However, due to some limitations of natural fibers, composite formulation
and processing parameters must be controlled to produce a product with improved properties. This study was conducted to investigate
the influence of flax fiber loading, use of compatibilizer and pretreatment on physical and mechanical properties of compression-molded
composite. In this study, untreated and treated (sodium hydroxide-treated and mild-bleached flax fibers) fibers at 15% and
30% of the total product mass were used in formulations. To investigate the effect of compatibilizer on product properties,
maleic anhydride grafted polypropylene (MAPP) was added at 5% by mass in the formulations. After extrusion of composites formulations,
they were formed using compression molding. Results indicated that using flax fiber in composites without pretreatment and
compatibilizer could result into products with inferior physical and mechanical properties; this could be compensated by the
use of a compatibilizer. However, the use of compatibilizer had some negative effects on some other physical properties like
color and melt flow index (MFI). 相似文献
77.
Monireh Sadat Mousavi Khosro Ashrafi Majid Shafie Pour Motlagh Mohhamad Hosein Niksokhan Hamid Reza Vosoughifar 《Environmental Modeling and Assessment》2017,22(5):431-444
Numerical and experimental analyses were applied to carbon monoxide (CO) concentration dispersion to monitor air quality in an enclosed residential complex parking area in Tehran. Firstly, the parking area was preliminary assessed through verifying the characteristics of the problem including the geometry and boundary conditions. Then, proportion of vehicular exhaust emissions was estimated and eventually experimental and numerical analyses were performed. In order to perform numerical calculation, a three-dimensional model was created to numerically simulate the enclosed residential complex parking area by FLUENT software that solves flow governing equations with finite volume method. In FLUENT, species model was selected to assess the dispersion of CO in flow domain. In experimental analysis, CO concentration was measured using sampling bags with a volume of 10 l in 4 min at 6 different points. The sample air was drawn into sampling bags by electric pumps. The findings show that the maximum amount of CO concentration is above the permissible standard recommended by the World Health Organization. Pollutant accumulation was significant in confined areas. In the place where openings exist, the level of accumulation was lower than other areas. The findings obtained from numerical simulation are in complete accord with experimental results. 相似文献
78.
Azizur Rahman M Hasegawa H Mahfuzur Rahman M Nazrul Islam M Majid Miah MA Tasmen A 《Chemosphere》2007,67(6):1072-1079
A glass house experiment was conducted to investigate the effect of soil arsenic on photosynthetic pigments, chlorophyll-a and -b, and their correlations with rice yield and growth. The experiment was designed with three replications of six arsenic treatments viz. control, 10, 20, 30, 60, 90 mg of As kg(-1) soil. Arsenic concentration in initial soil, to which the above mentioned concentrations of arsenic were added, was 6.44+/-0.24 mg kg(-1). Both chlorophyll-a and -b contents in rice leaf decreased significantly (p<0.05) with the increase of soil arsenic concentrations. No rice plant survived up to maturity stage in soil treated with 60 and 90 mg of As kg(-1). The highest chlorophyll-a and -b contents were observed in control treatment (2.62+/-0.24 and 2.07+/-0.14 mg g(-1) were the average values of chlorophyll-a and -b, respectively of the five rice varieties) while 1.50+/-0.20 and 1.04+/-0.08 mg g(-1) (average of five rice varieties) of chlorophyll-a and -b, respectively were the lowest. The content of photosynthetic pigments in these five rice varieties did not differ significantly (p>0.05) from each other in control treatment though they differed significantly (p<0.05) from each other in 30 mg of As kg(-1) soil treatment. Among the five rice varieties, chlorophyll content in BRRI dhan 35 was found to be mostly affected with the increase of soil arsenic concentration while BRRI hybrid dhan 1 was least affected. Well correlations were observed between chlorophyll content and rice growth and yield suggesting that arsenic toxicity affects the photosynthesis which ultimately results in the reduction of rice growth and yield. 相似文献
79.
Nimra Amin Fazal-ur- Rehman Shahid Adeel Tanvir Ahamd Majid Muneer Aminoddin Haji 《Environmental science and pollution research international》2020,27(7):6851-6860
Natural colors particularly animal-based colorants are employed in the field of cosmetics, food, and flavors and also gaining popularity in textiles, due to their soothing nature. In this study, the microwave-assisted extraction of colorant from cochineal insects for dyeing of bio-mordanted silk has been carried out. Acidic, methanolic, and acidified methanol solubilized media were used to extract the natural colorant from cochineal under microwave irradiation for 1–6 min. Bio-mordants have been employed at optimized conditions to make the process greener and sustainable. It is found that acid solubilized extract of pH 4, employed at 55 °C for 55 min containing 5 g/100 mL of Glauber’s salt as exhausting agent has given high color strength onto microwave-treated silk fabric. Suggested ISO standards for colorfastness have revealed that bio-mordants have given excellent color depth and excellent rating of fastness properties, compared with chemical mordants used. It is found that microwave treatment has not only improved the dyeing behavior of colorant extracted from cochineal in acid solubilized medium but also enhanced the color characteristics onto bio-mordanted silk fabric. 相似文献
80.
Majid Mohammadhosseini Esmaeil Soliemani 《Environmental monitoring and assessment》2013,185(11):8925-8941
Ethyl(2-ethylamino)thiophenol-2,6-pyridinedicarboxylate (ETPD) was synthesized from the reaction of disodium pyridine-2,6-dicarboxylate with 1,2-dibromoethane in methanol, followed by treatment with 2-aminothiophenol. The spectral characterization of ETPD is described in detail. This electron-donating agent was successfully utilized for simultaneous enrichment of ultra trace levels of copper and lead in a wide variety of samples. By passing the aqueous solutions through octadecylsilyl bonded phase membrane disks impregnated with 12 mg of ETPD at flow rates of 45 mL min?1, Cu and Pb were selectively trapped on the disk surface over the pH range 3.0 to 7.0, whereas most other ions were negligibly retained. Numerous chemical parameters affecting sorption and subsequent elution were also investigated. The target ions were stripped from the disk surfaces by reverse flow, at rates of 12 mL min?1, and were immediately introduced to the nebulizer of an atomic absorption spectrometer. This inexpensive and off-line method offers enrichment factors of 400 and 300 and detection limits of 2.5 and 0.2 μg L?1 for copper and lead, respectively. The potential applicability of the method was confirmed by its reliable use in quantification of these elements in some real water samples, industrial effluents, three tea samples and peppers, as well as by comparison with graphite furnace atomic absorption spectrometric determinations. 相似文献