The conventional Rackett model for predicting liquid molar volume has been modified to cater for the effect of molar composition of the Deep Eutectic Solvents(DES). The experimental molar volume data for a group of co...The conventional Rackett model for predicting liquid molar volume has been modified to cater for the effect of molar composition of the Deep Eutectic Solvents(DES). The experimental molar volume data for a group of commonly used DES has been used for optimizing the improved model. The data involved different molar compositions of each DES. The validation of the new model was performed on another set of DESs. The average relative deviation of the model on the training and validation datasets was approximately 0.1% while the Rackett model gave a relative deviation of more than 1.6%. The modified model deals with variations in DES molar composition and temperature in a more consistent way than the original Rackett model which exhibits monotonic performance degradation as temperature moves away from reference conditions. Having the composition of the DES as a model variable enhances the practical utilization of the predicting model in diverse design and process simulation applications.展开更多
The Jiaoshiba shale gasfield is located in the Fuling area of the Sichuan Basin,with the Upper Ordovician Wufeng-Lower Silurian Longmaxi Fm as the pay zone.At the bottom of the pay zone,a high-quality shale gas reserv...The Jiaoshiba shale gasfield is located in the Fuling area of the Sichuan Basin,with the Upper Ordovician Wufeng-Lower Silurian Longmaxi Fm as the pay zone.At the bottom of the pay zone,a high-quality shale gas reservoir about 20 m thick is generally developed with high organic contents and gas abundance,but its resistivity is relatively low.Accordingly,the gas saturation calculated by formulas(e.g.Archie)using electric logging data is often much lower than the experiment-derived value.In this paper,a new method was presented for calculating gas saturation more accurately based on non-electric logging data.Firstly,the causes for the low resistivity of shale gas reservoirs in this area were analyzed.Then,the limitation of traditional methods for calculating gas saturation based on electric logging data was diagnosed,and the feasibility of the neutronedensity porosity overlay method was illustrated.According to the response characteristics of neutron,density and other porosity logging in shale gas reservoirs,a model for calculating gas saturation of shale gas was established by core experimental calibration based on the density logging value,the density porosity and the difference between density porosity and neutron porosity,by means of multiple methods(e.g.the dual-porosity overlay method by optimizing the best overlay coefficient).This new method avoids the effect of low resistivity,and thus can provide normal calculated gas saturation of high-quality shale gas reservoirs.It works well in practical application.This new method provides a technical support for the calculation of shale gas reserves in this area.展开更多
In Mediterranean regions drought is the major factor limiting spring barley and durum wheat grain yields. This study aimed to compare spring barley and durum wheat root and shoot responses to drought and quantify rela...In Mediterranean regions drought is the major factor limiting spring barley and durum wheat grain yields. This study aimed to compare spring barley and durum wheat root and shoot responses to drought and quantify relationships between root traits and water uptake under terminal drought.One spring barley（Hordeum vulgare L. cv. Rum） and two durum wheat Mediterranean cultivars（Triticum turgidum L. var durum cvs Hourani and Karim） were examined in soil‐column experiments under well watered and drought conditions. Root system architecture traits, water uptake, and plant growth were measured. Barley aerial biomass and grain yields were higher than for durum wheat cultivars in well watered conditions. Drought decreased grain yield more for barley（47%） than durum wheat（30%, Hourani）. Root‐to‐shoot dry matter ratio increased for durum wheat under drought but not for barley, and root weight increased for wheat in response todrought but decreased for barley. The critical root length density（RLD） and root volume density（RVD） for 90% available water capture for wheat were similar to（cv. Hourani） or lower than（cv. Karim） for barley depending on wheat cultivar. For both species, RVD accounted for a slightly higher proportion of phenotypic variation in water uptake under drought than RLD.展开更多
Participating media are frequent in real-world scenes,whether they contain milk,fruit juice,oil,or muddy water in a river or the ocean.Incoming light interacts with these participating media in complex ways:refraction...Participating media are frequent in real-world scenes,whether they contain milk,fruit juice,oil,or muddy water in a river or the ocean.Incoming light interacts with these participating media in complex ways:refraction at boundaries and scattering and absorption inside volumes.The radiative transfer equation is the key to solving this problem.There are several categories of rendering methods which are all based on this equation,but using different solutions.In this paper,we introduce these groups,which include volume density estimation based approaches,virtual point/ray/beam lights,point based approaches,Monte Carlo based approaches,acceleration techniques,accurate single scattering methods,neural network based methods,and spatially-correlated participating media related methods.As well as discussing these methods,we consider the challenges and open problems in this research area.展开更多
基金Supported by Sultan Qaboos University,Petroleum and Chemical Engineering Department,Muscat Oman
文摘The conventional Rackett model for predicting liquid molar volume has been modified to cater for the effect of molar composition of the Deep Eutectic Solvents(DES). The experimental molar volume data for a group of commonly used DES has been used for optimizing the improved model. The data involved different molar compositions of each DES. The validation of the new model was performed on another set of DESs. The average relative deviation of the model on the training and validation datasets was approximately 0.1% while the Rackett model gave a relative deviation of more than 1.6%. The modified model deals with variations in DES molar composition and temperature in a more consistent way than the original Rackett model which exhibits monotonic performance degradation as temperature moves away from reference conditions. Having the composition of the DES as a model variable enhances the practical utilization of the predicting model in diverse design and process simulation applications.
文摘The Jiaoshiba shale gasfield is located in the Fuling area of the Sichuan Basin,with the Upper Ordovician Wufeng-Lower Silurian Longmaxi Fm as the pay zone.At the bottom of the pay zone,a high-quality shale gas reservoir about 20 m thick is generally developed with high organic contents and gas abundance,but its resistivity is relatively low.Accordingly,the gas saturation calculated by formulas(e.g.Archie)using electric logging data is often much lower than the experiment-derived value.In this paper,a new method was presented for calculating gas saturation more accurately based on non-electric logging data.Firstly,the causes for the low resistivity of shale gas reservoirs in this area were analyzed.Then,the limitation of traditional methods for calculating gas saturation based on electric logging data was diagnosed,and the feasibility of the neutronedensity porosity overlay method was illustrated.According to the response characteristics of neutron,density and other porosity logging in shale gas reservoirs,a model for calculating gas saturation of shale gas was established by core experimental calibration based on the density logging value,the density porosity and the difference between density porosity and neutron porosity,by means of multiple methods(e.g.the dual-porosity overlay method by optimizing the best overlay coefficient).This new method avoids the effect of low resistivity,and thus can provide normal calculated gas saturation of high-quality shale gas reservoirs.It works well in practical application.This new method provides a technical support for the calculation of shale gas reserves in this area.
基金EU-Framework 6 Program for funding the WatNitMed project 509107-Management Improvements of WUE and NUE of Mediterranean Strategic Crops
文摘In Mediterranean regions drought is the major factor limiting spring barley and durum wheat grain yields. This study aimed to compare spring barley and durum wheat root and shoot responses to drought and quantify relationships between root traits and water uptake under terminal drought.One spring barley（Hordeum vulgare L. cv. Rum） and two durum wheat Mediterranean cultivars（Triticum turgidum L. var durum cvs Hourani and Karim） were examined in soil‐column experiments under well watered and drought conditions. Root system architecture traits, water uptake, and plant growth were measured. Barley aerial biomass and grain yields were higher than for durum wheat cultivars in well watered conditions. Drought decreased grain yield more for barley（47%） than durum wheat（30%, Hourani）. Root‐to‐shoot dry matter ratio increased for durum wheat under drought but not for barley, and root weight increased for wheat in response todrought but decreased for barley. The critical root length density（RLD） and root volume density（RVD） for 90% available water capture for wheat were similar to（cv. Hourani） or lower than（cv. Karim） for barley depending on wheat cultivar. For both species, RVD accounted for a slightly higher proportion of phenotypic variation in water uptake under drought than RLD.
文摘Participating media are frequent in real-world scenes,whether they contain milk,fruit juice,oil,or muddy water in a river or the ocean.Incoming light interacts with these participating media in complex ways:refraction at boundaries and scattering and absorption inside volumes.The radiative transfer equation is the key to solving this problem.There are several categories of rendering methods which are all based on this equation,but using different solutions.In this paper,we introduce these groups,which include volume density estimation based approaches,virtual point/ray/beam lights,point based approaches,Monte Carlo based approaches,acceleration techniques,accurate single scattering methods,neural network based methods,and spatially-correlated participating media related methods.As well as discussing these methods,we consider the challenges and open problems in this research area.
