نتایج جستجو برای: water class

تعداد نتایج: 940812  

2014
Qing Gu Jinsong Deng Ke Wang Yi Lin Jun Li Muye Gan Ligang Ma Yang Hong

Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispens...

.  Introduction Old trees are important and key elements of forest sites and are of great value in terms of forest management, reforestation, silviculture and ecology. Although old trees constitute a small percentage of forest trees, they account for a large share of forest carbon reserve and play a vital role in carbon storage. Understanding the how geographical and site distribution of thes...

Journal: :iranian journal of veterinary medicine 2010
rasoul sheikh mohammadi ali hashemi karim mardani

the drb3 gene is a highly polymorphic major histocompatibility complex (mhc) class ii gene and plays an important role in variability of immune responsiveness and disease resistance. in the present study, the mhc class ii drb3 gene in water buffalo (bubalus bubalis) populations from northwest regions of iran was investigated through pcr-sscp. genomic dna was extracted from whole blood samples c...

2006
P. Stäuber J. K. Jørgensen E. F. van Dishoeck S. D. Doty A. O. Benz

Aims. We study the H2O chemistry in star-forming environments under the influence of a central X-ray source and a central far ultraviolet (FUV) radiation field. The X-ray models are applied to envelopes around low-mass Class 0 and I young stellar objects (YSOs). Methods. The gas-phase water chemistry is modeled as a function of time, hydrogen density and X-ray flux. To cover a wide range of phy...

Journal: :آب و خاک 0

introduction: iran is a vast country with limited water resources. iran is located in arid areas and average precipitation is estimated to be 250 mm. in recent years, water shortage has created many problems for iranian farmers. in these conditions, surface and ground water use is excessive. high consumption, low irrigation efficiency, bad time and geographical distribution of precipitation, po...

2010

Maintaining drinking water quality is essential to water companies and their customers. However, agricultural non-point source pollution of waterways is a major cause of water quality degradation. In this paper we examine the feasibility of using payments financed by a water company to pay farmers to adjust agricultural land management practices to protect water quality. We use the choice exper...

Journal: :بوم شناسی کشاورزی 0
سید حسام موسوی جواد وفابخش رضا صدرآبادی حقیقی

water deficit is a major factor influencing yield of canola (brassica napus l.) seed yield and oil content. a field experiment was conducted during 2010 growing season in the agriculture research station of torogh, mashhad, iran to evaluate responses of canola cultivars to limited water. experimental design was rcbd pattern with three replications. treatments were two irrigation regimes (based ...

This paper is devoted to the application of new low cost ceramic ultrafi ltration membranes material coming from the Tunisian ores (mud) which is usually considered as disastrous for the environment. A ceramic tubular support previously elaborated from mud was coated in the lumen side by slip casting method. After sintering at 650°C, the coated membrane shows homogeneou...

Journal: :مرتع و آبخیزداری 0
الهام السادات شکوهی دانش آموخته کارشناس ارشد مدیریت مناطق بیابانی، دانشکده منابع طبیعی، دانشگاه تهران، ایران. غلامرضا زهتابیان استاد دانشکده منابع طبیعی، دانشگاه تهران، ایران. علی طویلی دانشیار دانشکده منابع طبیعی، دانشگاه تهران، ایران.

more than 80% of iran’s area has arid and semi arid climate. therefore, iran is exposed to desertification process. practical activities in controlling desertification must be based on current desertification situation and its severity. based on this theory, evaluating desertification rate indices in khezrabad region was done based on imdpa model. in this research two factors with 10 indices we...

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