排序方式: 共有146条查询结果,搜索用时 296 毫秒
131.
Alireza Choobineh Mohammadali Lahmi Mostafa Hosseini Houshang Shahnavaz Reza Khani Jazani 《International journal of occupational safety and ergonomics》2004,10(4):411-424
Carpet weavers suffer from musculoskeletal problems mainly attributed to poor working postures. Their posture is mostly constrained by the design of workstations. This study was conducted to investigate the effects of 2 design parameters (weaving height and seat type) on postural variables and subjective experience, and to develop guidelines for workstation adjustments. At an experimental workstation, 30 professional weavers worked in 9 different conditions. Working posture and weavers' perceptions were measured. It was shown that head, neck and shoulder postures were influenced by weaving height. Both design parameters influenced trunk and elbows postures. The determinant factor for weavers' perception on the neck, shoulders and elbows was found to be weaving height, and on the back and knees it was seat type. Based on the results, the following guidelines were developed: (a) weaving height should be adjusted to 20 cm above elbow height; (b) a 10 degrees forward-sloping high seat is to be used at weaving workstations. 相似文献
132.
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
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Aghamiri SM Ghorbani Z Darafsheh A Torabzadeh H Fathivand AA Minuchehr A Jalinoos A 《Journal of environmental radioactivity》2006,89(3):212-218
The level of natural radiation in some regions of Ramsar, a northern coastal city of Iran, is known to be among the highest levels of natural radiation in the world. 226Ra existing in high concentrations in the soil of this region is washed by underground water and transferred to the surface. In this way, 226Ra enters the food chain of residents and substitutes within the hard body tissues of humans. 226Ra is one of the so-called bone seekers as its metabolic processes in the human body are similar to calcium and remains in hard tissues of body because of its long half-life, and being an alpha emitter causes dangerous effects on human health. The purpose of this study is to determine the concentration of 226Ra in the teeth of residents of these high-level natural radiation areas, compared with a control group. Thirteen teeth in five groups were studied as the case group and thirteen teeth in five corresponding control groups were inspected. The mean values of the activity of 226Ra in the case group and in the control group were 0.32 and 0.18mBqg(-1), respectively. 相似文献
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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
137.
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
138.
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
139.
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
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Pourshirband Nafiseh Nezamzadeh-Ejhieh Alireza 《Environmental science and pollution research international》2022,29(30):45276-45291
Environmental Science and Pollution Research - Nowadays, critical environmental pollution needs some novel, simple, effective, and cost-effective catalysts with high efficiency in the visible... 相似文献