A novel technique for the quick measurement moisture content of coal powder by microwave was studied. The effects of the various moisture contents on the measurement results were also discussed. The experimental resul...A novel technique for the quick measurement moisture content of coal powder by microwave was studied. The effects of the various moisture contents on the measurement results were also discussed. The experimental results show that the standard deviation is less than 0.36% when the moisture content of coal powder is 0.74%-16.90% and the standard deviation is less than 0.16% when the moisture content is 0.31%-1.49%. The experimental results indicate that a process of quick measurement moisture content of coal powder by microwave is practical.展开更多
In this study,we propose a new method for water holdup measurement of oil-in-water emulsions with a microwave resonance sensor(MRS).The angle and length of the electrode plate are optimized by HFSS simulation software...In this study,we propose a new method for water holdup measurement of oil-in-water emulsions with a microwave resonance sensor(MRS).The angle and length of the electrode plate are optimized by HFSS simulation software.Using a vector network analyzer(VNA),a static calibration experiment is conducted,and the resonant frequency distribution of oil-in-water emulsions is analyzed within an 80%–100%water holdup range.In addition,we observe and analyze the micron-sized oil bubble structure in the emulsifi ed state with an optical microscope.On this basis,a dynamic experiment of oil-in-water emulsions with high water cut and low velocity in a vertical upward pipe is conducted.S_(21) response curves of the MRS are obtained by the VNA under diff erent working conditions in real time.Finally,we analyze the relationship between the resonant frequency and water cut.Experimental results show that the MRS has an average resolution of 0.096%water cut for high water cut oil-in-water emulsions within the frequency range of 2.2–2.8 GHz.展开更多
The hydration film on particle surface plays an important role in bubble-particle adhesion in mineral flotation process. The thicknesses of the hydration films on natural hydrophobic coal and hydrophilic mica surfaces...The hydration film on particle surface plays an important role in bubble-particle adhesion in mineral flotation process. The thicknesses of the hydration films on natural hydrophobic coal and hydrophilic mica surfaces were measured directly by atomic force microscopy （AFM） based on the bending mode of the nominal constant compliance regime in AFM force curve in the present study. Surface and solid-liquid interfacial energies were calculated to explain the forming mechanism of the hydration film and atomic force microscopy data. The results show that there are significant differences in the structure and thickness of hydration films on coal and mica surfaces. Hydration film formed on mica surface with the thickness of 22.5 nm. In contrast, the bend was not detected in the nominal constant compliance regime. The van der Waals and polar interactions between both mica and coal and water molecules are characterized by an attractive effect, while the polar attractive free energy between water and mica （-87.36 mN/m） is significantly larger than that between water and coal （-32.89 mN/m）, which leads to a thicker and firmer hydration layer on the mica surface. The interfacial interaction free energy of the coal/water/bubble is greater than that of mica. The polar attractive force is large enough to overcome the repulsive van der Waals force and the low energy barrier of film rupture, achieving coal particle bubble adhesion with a total interfacial free energy of-56.30 mN/m.展开更多
Kuwait is located in hyper arid desert environment. This geographical location and irrational human activities accelerate the expansion of land degradation problem. In order to rehabilitate the degraded areas it is ne...Kuwait is located in hyper arid desert environment. This geographical location and irrational human activities accelerate the expansion of land degradation problem. In order to rehabilitate the degraded areas it is necessary to use soil and water resources in sustainable manner. Owing to these reasons it is essential to use appropriate methods based on the scientific diagnostics of the problem. It is compulsory to identify, specify and test different efficient, cost-effective and environment friendly sound sustainable sand control measures such as, semi-circular bunds, square micro catchment and checker board palm leaves to rehabilitate degraded lands in Liyah refilled quarries. To evaluate the impact of rehabilitation method through mulching with date palm leaves soil samples were collected （control and rehabilitation sites with square micro catchment） prior to the implementation plan and post completion of the project （three years）. In this study will be highlighted on detail the results of using square micro catchment and with short brief descriptions on other water harvesting techniques. The results showed an improvement of physical soil properties after the application of these techniques. Soil fertility increased through increasing the quantity of fine and very fine sand. The soil moisture at the surface soil increased from 0.085% to 1.62% after the treatment. The untreated soil has high bulk density about 2 g/cm3 and low porosity about 27%. However, after the soil was ploughed and mulched the bulk density decreased to 0.03 g/cm3. And porosity improved 98%. This study conserved the irrigation water through reducing the proportion of soil evaporation, in addition to the creation of optimum condition for plant growth. The aim of this study was to analyze the effect of using organic mulch date palm leaves with water harvesting techniques on the physical and biological properties of degraded soil in Liyah area.展开更多
Hydrothermal fuid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid f...Hydrothermal fuid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid from deep reservoir. However, because of seawater＇s little contribution to the forming of chimneys, it is usually covered by the abundant matter which is taken by hydrothermal fluid. Therefore, chimneys formed in ordinary deep elements, cannot be used to study the seawater＇s seawater hydrothermal activity, containing complex contribution to their formation. While the native sulfur chimneys, formed by hydrothermal activity near the sea area off Kueishantao, are single sulfur composition （over 99%）, and within chimneys distinct layers are seen. Different layers were sampled for trace element determination, with Inductively Coupled Plasma Mass Spectrometry （ICP-MS）. By analyzing the data, we consider C-layer （secondary inner-layer） as the framework layer of the chimney which formed early （Fig.4）, and its trace elements derive from hydrothermal fluid. While the trace elements within A, B, D layers have undergone later alteration. A, B layers are affected by seawater and D layer by hydrothermal fluid. The increase of trace elements of A and B layers was calculated using C layer as background. Based on the known typical volume of chimneys of the near sea area off Kueishantao, we calculated the volume of seawater that contributed trace element to chimneys formation to be about 6.37×10^4 L. This simple quantified estimate may help us better understand the seafloor hydrothermal activity and chimneys.展开更多
The weather system, meteorological conditions, and microphysics of cloud, fog, and rain droplets are studied during the formation, growth, maintenance, and shedding periods of ice accretion on wires in Enshi, Hubei Pr...The weather system, meteorological conditions, and microphysics of cloud, fog, and rain droplets are studied during the formation, growth, maintenance, and shedding periods of ice accretion on wires in Enshi, Hubei Province in China using 2008/2009 and 2009/2010 winter observations. The comprehensive observations include data of visibility, microphysics of fog and rain droplets, and ice thickness, as well as data from an automated weather station and other routinely recorded meteorological data. The results show that icing occurred during the passage of a cold front, with a high-pressure system and a cold temperature trough at 850 hPa, and a southeasterly at 500 hPa that provided abundant moisture. Ice formation usually started in the evening or early morning, and ice shed around noon the following day when the temperature was -1℃ to 0℃. The averaged liquid water content of the fog droplet was distinctly greater during the growth period than during the other three periods, and there was precipitation during the growth period in each case of ice accretion. The growth rate of the ice thickness was clearly correlated with the liquid water content, with a correlation coefficient of 0.62. Simulations using empirical equations were carried out, and the simulated ice thickness agreed with observations fairly well.展开更多
Lanthanide elements(Ln)play an important role in industry and agriculture.As a result of the increasing consumption of lanthanides,environmental emission of Ln has become detrimental to the health of flora and fauna.C...Lanthanide elements(Ln)play an important role in industry and agriculture.As a result of the increasing consumption of lanthanides,environmental emission of Ln has become detrimental to the health of flora and fauna.Current methods for trace lanthanides detection mainly rely on sophisticated instruments.In this article,a Ln^(3+)dependent DNAzyme was incorporated into a hydrogel to generate Ln^(3+)sensitive DNAzyme hydrogel for portable colorimetric detection.The enzyme strand and its substrate strand act as crosslinker and functional unit of the hydrogel with polyacrylamide chains as the scaffold and gold nanoparticles(AuNPs)as the indicator of hydrogel stability.Any ions in the Ln^(3+)series can trigger the cleavage of substrate strand by activating the enzyme strand,thereby decreasing the crosslink ratio and leading to collapse of the hydrogel.The release of the encapsulated AuNPs turns the supernatant wine red.Using this colorimetric method,Ln^(3+)can be detected with high sensitivity,with a limit of detection(LOD)of 20 nM for Ce^(3+).The hydrogel responds specifically to any Ln^(3+)ion and works well with the spiked lake sample without the need of instruments and skilled operators.Our results suggest that the lanthanide responsive hydrogel can be used for portable and sensitive detection of Ln^(3+)contamination in the field.展开更多
文摘A novel technique for the quick measurement moisture content of coal powder by microwave was studied. The effects of the various moisture contents on the measurement results were also discussed. The experimental results show that the standard deviation is less than 0.36% when the moisture content of coal powder is 0.74%-16.90% and the standard deviation is less than 0.16% when the moisture content is 0.31%-1.49%. The experimental results indicate that a process of quick measurement moisture content of coal powder by microwave is practical.
基金supported by the National Natural Science Foundation of China(Grant Nos.42074142 and 51527805)。
文摘In this study,we propose a new method for water holdup measurement of oil-in-water emulsions with a microwave resonance sensor(MRS).The angle and length of the electrode plate are optimized by HFSS simulation software.Using a vector network analyzer(VNA),a static calibration experiment is conducted,and the resonant frequency distribution of oil-in-water emulsions is analyzed within an 80%–100%water holdup range.In addition,we observe and analyze the micron-sized oil bubble structure in the emulsifi ed state with an optical microscope.On this basis,a dynamic experiment of oil-in-water emulsions with high water cut and low velocity in a vertical upward pipe is conducted.S_(21) response curves of the MRS are obtained by the VNA under diff erent working conditions in real time.Finally,we analyze the relationship between the resonant frequency and water cut.Experimental results show that the MRS has an average resolution of 0.096%water cut for high water cut oil-in-water emulsions within the frequency range of 2.2–2.8 GHz.
基金Project（2014BAB01B03） supported by the National Key Technology R＆D Program During the 12th Five-Yean Plan of China Project（51774286） supported by the National Natural Science Foundation of China Project（BK20150192） supported by the Natural Science Foundation of Jiaaagsu Province, China
文摘The hydration film on particle surface plays an important role in bubble-particle adhesion in mineral flotation process. The thicknesses of the hydration films on natural hydrophobic coal and hydrophilic mica surfaces were measured directly by atomic force microscopy （AFM） based on the bending mode of the nominal constant compliance regime in AFM force curve in the present study. Surface and solid-liquid interfacial energies were calculated to explain the forming mechanism of the hydration film and atomic force microscopy data. The results show that there are significant differences in the structure and thickness of hydration films on coal and mica surfaces. Hydration film formed on mica surface with the thickness of 22.5 nm. In contrast, the bend was not detected in the nominal constant compliance regime. The van der Waals and polar interactions between both mica and coal and water molecules are characterized by an attractive effect, while the polar attractive free energy between water and mica （-87.36 mN/m） is significantly larger than that between water and coal （-32.89 mN/m）, which leads to a thicker and firmer hydration layer on the mica surface. The interfacial interaction free energy of the coal/water/bubble is greater than that of mica. The polar attractive force is large enough to overcome the repulsive van der Waals force and the low energy barrier of film rupture, achieving coal particle bubble adhesion with a total interfacial free energy of-56.30 mN/m.
文摘Kuwait is located in hyper arid desert environment. This geographical location and irrational human activities accelerate the expansion of land degradation problem. In order to rehabilitate the degraded areas it is necessary to use soil and water resources in sustainable manner. Owing to these reasons it is essential to use appropriate methods based on the scientific diagnostics of the problem. It is compulsory to identify, specify and test different efficient, cost-effective and environment friendly sound sustainable sand control measures such as, semi-circular bunds, square micro catchment and checker board palm leaves to rehabilitate degraded lands in Liyah refilled quarries. To evaluate the impact of rehabilitation method through mulching with date palm leaves soil samples were collected （control and rehabilitation sites with square micro catchment） prior to the implementation plan and post completion of the project （three years）. In this study will be highlighted on detail the results of using square micro catchment and with short brief descriptions on other water harvesting techniques. The results showed an improvement of physical soil properties after the application of these techniques. Soil fertility increased through increasing the quantity of fine and very fine sand. The soil moisture at the surface soil increased from 0.085% to 1.62% after the treatment. The untreated soil has high bulk density about 2 g/cm3 and low porosity about 27%. However, after the soil was ploughed and mulched the bulk density decreased to 0.03 g/cm3. And porosity improved 98%. This study conserved the irrigation water through reducing the proportion of soil evaporation, in addition to the creation of optimum condition for plant growth. The aim of this study was to analyze the effect of using organic mulch date palm leaves with water harvesting techniques on the physical and biological properties of degraded soil in Liyah area.
基金Supported by the Pilot Project of Knowledge Innovation Project, Chinese Academy of Sciences (No.KZCX2-YW-211and KZCX3-SW- 223)the National Natural Science Foundation of China (No. 40830849)the Special Foundation for the Eleventh Five-Year Plan of COMRA (No. DYXM-115-02-1-03).
文摘Hydrothermal fuid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid from deep reservoir. However, because of seawater＇s little contribution to the forming of chimneys, it is usually covered by the abundant matter which is taken by hydrothermal fluid. Therefore, chimneys formed in ordinary deep elements, cannot be used to study the seawater＇s seawater hydrothermal activity, containing complex contribution to their formation. While the native sulfur chimneys, formed by hydrothermal activity near the sea area off Kueishantao, are single sulfur composition （over 99%）, and within chimneys distinct layers are seen. Different layers were sampled for trace element determination, with Inductively Coupled Plasma Mass Spectrometry （ICP-MS）. By analyzing the data, we consider C-layer （secondary inner-layer） as the framework layer of the chimney which formed early （Fig.4）, and its trace elements derive from hydrothermal fluid. While the trace elements within A, B, D layers have undergone later alteration. A, B layers are affected by seawater and D layer by hydrothermal fluid. The increase of trace elements of A and B layers was calculated using C layer as background. Based on the known typical volume of chimneys of the near sea area off Kueishantao, we calculated the volume of seawater that contributed trace element to chimneys formation to be about 6.37×10^4 L. This simple quantified estimate may help us better understand the seafloor hydrothermal activity and chimneys.
基金supported by National Key Technology R&D Program of China (Grant No. 2008BAC48B01)National Natural Science Foundation of China (Grant No. 40775012)+1 种基金the Jiangsu Province Qinglan Project for Cloud Fog Precipitation and the Aerosol Research Groupa project funded by the Priority Acadenic Program Development of Jiangsu Higher Education Institutions
文摘The weather system, meteorological conditions, and microphysics of cloud, fog, and rain droplets are studied during the formation, growth, maintenance, and shedding periods of ice accretion on wires in Enshi, Hubei Province in China using 2008/2009 and 2009/2010 winter observations. The comprehensive observations include data of visibility, microphysics of fog and rain droplets, and ice thickness, as well as data from an automated weather station and other routinely recorded meteorological data. The results show that icing occurred during the passage of a cold front, with a high-pressure system and a cold temperature trough at 850 hPa, and a southeasterly at 500 hPa that provided abundant moisture. Ice formation usually started in the evening or early morning, and ice shed around noon the following day when the temperature was -1℃ to 0℃. The averaged liquid water content of the fog droplet was distinctly greater during the growth period than during the other three periods, and there was precipitation during the growth period in each case of ice accretion. The growth rate of the ice thickness was clearly correlated with the liquid water content, with a correlation coefficient of 0.62. Simulations using empirical equations were carried out, and the simulated ice thickness agreed with observations fairly well.
基金supported by the National Basic Research Program of China(2013CB933703)the National Natural Science Foundation of China(91313302,21205100,21275122,21075104)+2 种基金the National Instrumentation Program(2011YQ03012412)the National Found for Fostering Talents of Basic Science(J1310024)the National Science Foundation for Distinguished Young Scholars(21325522)
文摘Lanthanide elements(Ln)play an important role in industry and agriculture.As a result of the increasing consumption of lanthanides,environmental emission of Ln has become detrimental to the health of flora and fauna.Current methods for trace lanthanides detection mainly rely on sophisticated instruments.In this article,a Ln^(3+)dependent DNAzyme was incorporated into a hydrogel to generate Ln^(3+)sensitive DNAzyme hydrogel for portable colorimetric detection.The enzyme strand and its substrate strand act as crosslinker and functional unit of the hydrogel with polyacrylamide chains as the scaffold and gold nanoparticles(AuNPs)as the indicator of hydrogel stability.Any ions in the Ln^(3+)series can trigger the cleavage of substrate strand by activating the enzyme strand,thereby decreasing the crosslink ratio and leading to collapse of the hydrogel.The release of the encapsulated AuNPs turns the supernatant wine red.Using this colorimetric method,Ln^(3+)can be detected with high sensitivity,with a limit of detection(LOD)of 20 nM for Ce^(3+).The hydrogel responds specifically to any Ln^(3+)ion and works well with the spiked lake sample without the need of instruments and skilled operators.Our results suggest that the lanthanide responsive hydrogel can be used for portable and sensitive detection of Ln^(3+)contamination in the field.
