نتایج جستجو برای: pore water

تعداد نتایج: 583626  

Journal: :تحقیقات مهندسی کشاورزی 0
علی دیندارلو دانشجوی سابق کارشناسی ارشد علیرضا سپاسخواه استاد گروه آبیاری و زهکشی دانشکده کشاورزی، دانشگاه شیراز

solute transport processes are affected by soil pore water velocity distribution. pore size distribution, which can be used to infer pore water velocity distribution, can be estimated from a soil water retention curve (n). in this study, a solute breakthrough curve was simulated using soil hydraulic parameters in four different soils. to evaluate the proposed model, predictions were compared to...

Journal: :تحقیقات آب و خاک ایران 0
حجت احمدی حسن رحیمی عباس سروش عبدالحسین هورفر

constant rate of strain (crs) consolidation is a rapid test method used for determination of compressibility of clayey soils. in a crs test, the appropriate strain rate is selected based on pore water pressure ratio, i.e. the ratio of pore pressure to total stress. in the present study, to investigate the effect of strain rate on variation of relative pore water pressure, four different clay sa...

Journal: :علوم باغبانی ایران 0
حسین مزاری دانشجوی سابق کارشناسی ارشد، پردیس کشاورزی و منابع طبیعی دانشگاه تهران، کرج مجتبی دلشاد دانشیار، پردیس کشاورزی و منابع طبیعی دانشگاه تهران، کرج عبد الکریم کاشی استاد، پردیس کشاورزی و منابع طبیعی دانشگاه تهران، کرج

soilless media have different physical properties. change in air space of mix substrate can cause change in fertigation management and plant growth and yield. physical properties (water holding capacity, effective air-filled pore space, effective pore space) of 50 mixed substrates were measured to evaluate the effect of air-filled pore space on growth of tomato transplant and it's water us...

Journal: :international journal of civil engineering 0
h. soltani-jigheh amirkabir university of technology a. soroush amirkabir university of technology

mixed clayey soils occur as mixtures of sand (or gravel) and clay in widely varying proportions. their engineering behavior has not been comprehensively studied yet. an experimental program, comprising monotonic, cyclic, and post-cyclic triaxial tests was undertaken on compacted clay-granular material mixtures, having different proportions of clay and sand or gravel. this paper presents the res...

Journal: :international journal of environmental research 2011
j. lee h. zhang y. liu x. liu g. miao

approach of organic material anaerobic biodegradation and species of organic matter in sediment are discussed, and then a classifying method of the species is proposed on a new viewpoint. the pore water sediment oxygen demand (sod) numerical model in bottom sediment system is proposed originally, which differs from other advection-dispersion-sorption (ads) model in adding a sod-creating term. t...

Journal: :international journal of environmental research 2014
p. temporetti g. beamud e. pedrozo

the parameters used to determine the trophic state of a water body are: total phosphorus (tp),transparency (secchi disk depth) and chlorophyll a. however, these parameters show strong seasonalfluctuations which may hinder the estimation of trophic state. some authors have proposed that sediments be used as an additional tool to evaluate the trophic state of a water body. the aim of this study w...

Journal: :آب و خاک 0
حجت احمدی حسن رحیمی عباس سروش

abstract at present study constant rate of strain (crs) consolidation under non-darcy condition was investigated. in this study a governing conditions of drainage pore water were investigated using proposed equation. the crs experiments under different rates of strain were conducted on different soil samples. results these experiments and there comparison with proposed equation showed that flow...

Journal: :international journal of civil engineering 0
faradjollah askari orang farzaneh

although some 3d slope stability algorithms have been proposed in recent three decades, still role of pore pressures in three dimensional slope stability analyses and considering the effects of pore water pressure in 3d slope stability studies needs to be investigated. in this paper, a limit analysis formulation for investigation of role of the pore water pressure in three dimensional slope sta...

Gelatin is considered as a partially degraded product of collagen and it is a biodegradable polymer which can be used to produce scaffolds for tissue engineering. Three-dimensional, porous gelatin scaffolds were fabricated by thermally induced phase separation and freeze-drying method. Their porous structure and pore size were characterized by scanning electron microscopy. Scaffolds with differ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علوم و فنون مازندران 0

مدل روزنه های موازی موج دار (corrugated oarallel bundle model) برای تعریف اثر ساختمان روزنه ها در نفوذ-واکنش (diffusion and reaction) در کاتالیستهای متخلخل بکار می رود. در مدل روزنه های موج دار، از یک دسته روزنه های اصلی (pore) استفاده شده است . هر یک از این روزنه های اصلی دارای یکسری عناصر روزنه می باشد که هر عنصر دارای یک شعاع تعیین شده به صورت اتفاقی از یک توزیع اندازه روزنه ها (pore size di...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید