Coal bump is a dynamic process,thus it is necessary to reveal the process validly.2D-ball code is an efficient approach developed by the authors based on the basicDEM rationale proposed by Cundall.Numerical simulation...Coal bump is a dynamic process,thus it is necessary to reveal the process validly.2D-ball code is an efficient approach developed by the authors based on the basicDEM rationale proposed by Cundall.Numerical simulations show that the coal bump experiencesa process of energy accumulation,sudden release of energy and energy decrease.The stiffness of coal particles has a great influence on the coal bump morphosisand particle velocity.Generally,the larger the stiffness of particles,the longer the shootingoff period and the larger the bump velocity.This is in agreement with the results of laboratoryexperiment and in-situ studies.However,the stiffness of particles has an influence onthe quantity value energy and no influence on the releasing energy pattern of the coalbump.展开更多
At present, all aspects of China have entered the era of a rapid development, while the development speed of digital electronic technology is especially outstanding. This is a new way for China' s new personnel train...At present, all aspects of China have entered the era of a rapid development, while the development speed of digital electronic technology is especially outstanding. This is a new way for China' s new personnel training, and also proposes higher requirements on this type of personnel training institutions. In view of the demands of society and different majors on personnel, an enhancement to the standardized management of electronic laboratory operations becomes one of the important tasks for personnel training institutions. In this paper, how to practice the standardization management in an all-round way is discussed centered at college and university students' electronic laboratory.展开更多
Elemental mercury(Hg^0)re-emissions from slurries and solutions were evaluated in a lab-scale simulated scrubber.Oxidized mercury(Hg^2 +)standard solution was injected into the simulated scrubber at a desired rat...Elemental mercury(Hg^0)re-emissions from slurries and solutions were evaluated in a lab-scale simulated scrubber.Oxidized mercury(Hg^2 +)standard solution was injected into the simulated scrubber at a desired rate to simulate absorbing and dissolving of Hg^2 +in the flue gas across wet flue gas desulfurization(WFGD)systems. PS analytical mercury analyzer was used to continuously determine Hg0re-emission concentrations in the carrier gas from the scrubber.Sulfite ion in the slurry of CaSO3 was validated to reduce Hg ^2+to Hg^ 0,while no Hg ^0 re-emission occurred from slurries of CaSO4 and CaO.Transitional metal ions with low chemical valence such as Fe^2 +,Pb ^2+,Ni ^2+, AsO2^-and Cu ^+were used to prepare solutions with concentration levels of mmol·L^-1.Reduction reaction of Hg^2 +to Hg 0was observed from these solutions.Reduction capabilities for the different transitional metal ions in the solutions were:Pb^2 +〉Cu ^+〉Fe^ 2+〉 AsO2^-〉Ni ^2+.展开更多
Clay has a significant influence on the relationship between resistivity index I and water saturation Sw (i.e, I-Sw relationship) of reservoir rocks because it complicates the current paths of these rocks. It is dif...Clay has a significant influence on the relationship between resistivity index I and water saturation Sw (i.e, I-Sw relationship) of reservoir rocks because it complicates the current paths of these rocks. It is difficult to reveal the physical mechanisms of these clay effects on the conductivities of various rocks by physical laboratory measurements because the pore structure, micro distribution and content of clay inside a rock can not be observed and controlled during the experiments. We present a digital rock approach to study these clay effects on the electrical transport properties of reservoir rocks at pore scale using lattice gas automation (LGA) method. The digital rock samples are constructed with the information of grain size distribution from SEM images of reservoir rocks. The LGA is then applied on these digital rocks fully saturated with fluids to simulate the electrical transport properties for revealing the effects of volume and distribution patterns of clay on the non-Archie behaviors of the I-Sw relationship. The very good agreement between the simulated results and the laboratory measurements clearly demonstrates the validity of the LGA in numerical research of rock physics. Based on these studies, a new model has been developed for quantitatively describing the relationship between the saturation exponent and the volume of clay (Vsh). This development may improve the evaluation for the fluid saturations in reservoir rocks.展开更多
Objective: To study the distribution of I_ Ca,L in endomyocardium(Endo), mid-myocardium(Mid) and epicardium(Epi) in female and male rabbit ventricle and to elucidate the mechanism of sex difference in drug-associated ...Objective: To study the distribution of I_ Ca,L in endomyocardium(Endo), mid-myocardium(Mid) and epicardium(Epi) in female and male rabbit ventricle and to elucidate the mechanism of sex difference in drug-associated torsade de pointes. Methods: Whole-cell patch clamp technique was used to record action potential and I_Ca,L. Results: Action potential duration ofMidinfemale rabbit heart waslonger thanthat in male and transmural dispersion of repolarization in female was largerthan thatinmale. The densities of I_ Ca,L in Endo, Mid and Epi of female rabbits were (7.1±0.6), (10.4±0.9) and (9.6±1.1) pA/pF and they were (9.1±0.9), (10.5±1.0) and (9.8±0.9) pA/pF in male respectively. Transmural heterogeneity of I_ Ca,L in female ventricle was more significant than that in male rabbit.Conclusion:Female rabbitspossessmoresignificant transmural heterogeneityof I_Ca,L,whichmaybe responsiblefor largertransmuraldispersion of repolarization and more drug-associated torsade de pointes in female.展开更多
This study aims to (1) obtain a pure extract of Sargassumfilipendula fucoxanthin, (2) determine the effect of concentration of fucoxanthin against HeLa cells, and (3) determine the effect of concentration of fuc...This study aims to (1) obtain a pure extract of Sargassumfilipendula fucoxanthin, (2) determine the effect of concentration of fucoxanthin against HeLa cells, and (3) determine the effect of concentration of fucoxanthin against cancer cell lymphocytes. The benefit of this research is to find out that fucoxanthin can be used as an anti-cancer treatment. The study was conducted in September 2013 at the Laboratory of Fishery Product Technology FPIK UB and UB Medical Biomedical Laboratories, Malang. Sampling brown seaweed (Sargassum filipendula) of the District Rural Padike Talango Sumenep Madura. Extracted isolated by column chromatography using silica gel stationary phase and mobile phase hexane:ethyl acetate (6:4, v/v) ± 100 mL, then identified by TLC using the stationary phase, a silica gel F-254 HPLC with ODS stationary phase (C-18) 5 mL with a mobile phase of methanol, acetone and ammonium acetate (IM) (80:10:10, v/v) and a flow rate of 1.0 mL/min pigment solution of 20 mL compared with the standard of Japan. Research results indicate that, spectra maximum wavelength of 450 nm and 446 nm with a minimum of acetone solvent. HPLC has the same retention time = 10.12 standard, namely Sargassum filipendula = 10.11. By giving some of the best concentrations at 100 ppm is lethal HeLa cells ebesar 5236% which means that fucoxanthin effect against HeLa cells have the potential fucoxanthin that can induce cell apoptosis that occurs in HeLa cells, it is possible because of the anti-carcinogenic fucoxanthin mempuyai structure unique. While the cell lymphocytes in the dosage of 100 ppm were dead at 8.788%, the effect of the toxicity of a substance can be observed from how many dead lymphocytes when compared with the state charity by observing level of lymphocyte proliferation.展开更多
Despite the developments of sectors which aim at valorizing recyclable materials, landfills remain essential in integrated waste management. The construction of such infrastructures is an engineering challenge that mu...Despite the developments of sectors which aim at valorizing recyclable materials, landfills remain essential in integrated waste management. The construction of such infrastructures is an engineering challenge that must be proven over the long term. The purpose of this study is to understand the modification of the hydromechanical properties of bottom liners of landfills that may occur during their exploitation under leachate action. To do so, on the basis of its parameters of nature, a swelling clay from Burkina Faso is selected from soils of seven localities in Burkina Faso (West Africa). Laboratory tests carried out with distilled water and then with a young synthetic leachate show a degradation of the permeability of this clay from 2.42 × 10^-10 m/s to 1.01 × 10^-9 m/s. In addition, leachate leads to an inhibition of the swelling and a remarkable increase of its compressibility, inducing significant settlement. With the increase in permeability, the primary consolidation settlement is increasing faster. Changes in the hydromechanical behavior can be attributed to the clays mineralogy, mainly cation exchange and the development of the diffuse double layer.展开更多
In order to investigate the likely allelopathic potential of an aqueous extract and powder of Achillea (,4chillea santolina) on the germination and seedling growth of pea (Cicer arietinum), safflower (Carthamus t...In order to investigate the likely allelopathic potential of an aqueous extract and powder of Achillea (,4chillea santolina) on the germination and seedling growth of pea (Cicer arietinum), safflower (Carthamus tinctorius L.) and wheat (Triticum sativum), an experiment was carried out at the laboratory and greenhouse of agriculture faculty of Sho3hid Bahonar University of Kerman, Iran, from October 2009 to March 2010. A completely randomized design with three replicates using five extract concentrations of achillea plant including 0, 25, 50, 75, and 100 g Ll and four amounts of powder of it including 0, 7.5, 15 and 30 g kg1 of soil was employed in laboratory and greenhouse experiments, respectively. All extract concentrations of achillea except 25 g Ll inhibited pea and wheat seed germination significantly, but had no inhibitory effect on the germination of safflower, The powder of mature achillea plants affected the fresh and dry weight and shoots length in these crops negatively compared with the control in all levels. Therefore use of this plant should be prevented in rotation or intercropping with these three crop plants. Further research conducted in the analytical laboratory as well as in the field is needed before a practical application of the extract and powder as weed inhibiting agent can be recommended.展开更多
This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtig...This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space.展开更多
The aim of this paper is to establish LIMS (laboratory information management system) for the tea pesticides analysis accredited laboratories in Taiwan. The LIMS could help Tungting station and Nantou pesticide insp...The aim of this paper is to establish LIMS (laboratory information management system) for the tea pesticides analysis accredited laboratories in Taiwan. The LIMS could help Tungting station and Nantou pesticide inspection station to computerize the pesticide analysis data. It has completed eight management subsystems so far, including the basic information management subsystem, thesample processing management subsystem, the analysis data management subsystem, the analysis report management subsystem, the inspection standard management subsystem, the instrument connection management subsystem, the laboratory personnel training management subsystem and the laboratory quality document management subsystem. Using the automatic tea pesticide analysis information management system could help laboratory operations to reduce the amount of excess paperwork and human resource, which could ensure the analysis data quality is traceable and reliable.展开更多
Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed a...Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed active switching technology,they successfully conducted the world's longest-more than 90km-round-robin differential phase shift(RRDPS)quantum key distribution experiment.展开更多
Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic p...Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic plants by Callosciurus erythraeus introduced in the Pampas Region of Argentina. We identified and characterized entire and damaged seeds found in squirrel faeces and evaluated the germination capacity and viability of entire seeds in laboratory assays. We collected 120 samples of squirrel faeces that contained 883 pellets in seasonal surveys conducted between July 2011 and June 2012 at 3 study sites within the main invasion focus of C. erythraeus in Argentina. We found 226 entire seeds in 21% of the samples belonging to 4 species of exotic trees and shrubs. Germination in laboratory assays was recorded for Morus alba and Casuarina sp.; however, germination percentage and rate was higher for seeds obtained from the fruits than for seeds obtained from the faeces. The largest size of entire seeds found in the faeces was 4.2 ~ 4.0 ram, whereas the damaged seeds had at least 1 dimension ≥ 4.7 ram. Our results indi- cated that C. erythraeus can disperse viable seeds of at least 2 species of exotic trees. C. erythraeus predated seeds of other naturalized species in the region. The morphometric description suggested a restriction on the maximum size for the passage of entire seeds through the digestive tract of squirrels, which provides useful information to predict its role as a potential disperser or predator of other species in other invaded communities.展开更多
Protection of entanglement from disturbance of the environment is an essential task marion processing. We examine the validity and limitation of the weak measurement and reversal in quantum infor- (WMR) operation in...Protection of entanglement from disturbance of the environment is an essential task marion processing. We examine the validity and limitation of the weak measurement and reversal in quantum infor- (WMR) operation in the protection of distributed entanglement from various decoherence sources. Since the entanglement variation can be investigated analytically for an arbitrarily entangled bipartite pure state under three kinds of typical noisy quantum channels, we show explicitly that the WMR operation indeed helps for protecting distributed entanglement from ampli- tude damping and phase damping, but not for depolarizing. Bxperimental feasibility for testing our results is discussed using current laboratory techniques.展开更多
The gas and particle time-averaged velocity rand RMS fluctuation velocity of swirling gas-particle flows in a spouting-cyclone combustor were measured by a hot-ball probe and a conventional LDV system. The results sho...The gas and particle time-averaged velocity rand RMS fluctuation velocity of swirling gas-particle flows in a spouting-cyclone combustor were measured by a hot-ball probe and a conventional LDV system. The results show large velocity slip between the two phases both in tangential and axial directions and high nonisotropic turbulence of the two phases were also observed which is favorable to coal combustion. The particle RMS fluctuation velocity is higher than the gas RMS fluctuation velocity only in some regions of the flow field.展开更多
Thyrotoxicosis may present in many ways;severe vomiting as a prominent symptom of thyrotoxicosis is uncommon.In this paper,we report a 24-year-old Chinese male with hyperthyroidism who presented with recurrent severe ...Thyrotoxicosis may present in many ways;severe vomiting as a prominent symptom of thyrotoxicosis is uncommon.In this paper,we report a 24-year-old Chinese male with hyperthyroidism who presented with recurrent severe vomiting.The patient had had intermittent vomiting for seven years and had lost approximately 15 kg of weight.Gastroscopic examinations revealed chronic gastritis and one occasion peptic ulcer.He was treated with antacid and proton pump inhibitors,but his symptoms had no relief.His presenting symptoms suggested hyperthyroidism and were confirmed by laboratory data.After a month of propylthiouracil therapy,his symptoms were relieved.It should be noted that hyperthyroidism patients can have unexplained vomiting,and that hyperthyroidism may coexist with peptic ulcer in rare cases.Awareness of such atypical presentations of hyperthyroidism may help to make a correct diagnosis.展开更多
The observation of 26Al is an useful tool for γ-ray astronomy and in studies of galactic chemical evolution. The most likely mechanism for 26Al nucleosynthesis is in the hydrogen burning MgAI cycle, and the 26Al prod...The observation of 26Al is an useful tool for γ-ray astronomy and in studies of galactic chemical evolution. The most likely mechanism for 26Al nucleosynthesis is in the hydrogen burning MgAI cycle, and the 26Al production reaction 25Mg(p, γ)26Al at the important temperature range below T = 0.2 GK is still not well known. The spectroscopic factor of 58 keV resonance level in 26Al is determined with shell model calculation and then used to deduce the resonance strength of the 25Mg(p, γ)26Al reaction. The result provides a reference for the future 25Mg(p, γ)26Al direct measurement at Jinping underground laboratory.展开更多
We study a minimal extension of the standard model by introducing three right-handed neutrinos and a new scotogenic scalar doublet,in which the mass splittings between neutral and charged components are responsible fo...We study a minimal extension of the standard model by introducing three right-handed neutrinos and a new scotogenic scalar doublet,in which the mass splittings between neutral and charged components are responsible for the W-boson mass newly measured by the CDF Collaboration.This model can not only generate non-vanishing Majorana neutrino masses via the interaction of right-handed neutrinos and scotogenic scalars,but also explain the Universe’s missing matter in the form of FIMP dark matter.We also study the influence of the mass splitting on the first order electroweak phase transition,and find that it can further enhance the transition strength and thus induce gravitational waves during the phase transition,which may be detected in the forthcoming detectors such as U-DECIGO.展开更多
Recently, Sandia Laboratories developed a neutron scatter camera to detect special nuclear materials. This camera exhibits the following advantages: high efficiency, direction discrimination, neutron-gamma discriminat...Recently, Sandia Laboratories developed a neutron scatter camera to detect special nuclear materials. This camera exhibits the following advantages: high efficiency, direction discrimination, neutron-gamma discrimination ability, and wide field of view. However, using the direct projection method, the angular resolution of this camera is limited by uncertainties in the energies estimated from pulse height and time of flight measurements. In this study, we established an eight-element neutron scatter camera and conducted the experiment with a ^(252)Cf neutron source. The results show that it has an angular resolution better than 8°(1s) and a detection efficiency of approximately 2.6′10-4. Using maximum likelihood expectation maximization method, the image artifact was eliminated, and the angular resolution was improved. We proposed an average scattering angle method to estimate the scattering energy of neutrons and Compton gamma rays. As such, we can obtain a recognizable image and energy spectrum of the source with some degradation of energy and image resolutions. Finally, a newly measured light response function based on the MPD^(-4) device was used for image reconstruction. Although we did not obtain a better result than that of the standard light response function, we have observed the effects of light response function on image reconstruction.展开更多
基金Supported by the National Natural Science Fundation of China(50534080,50674063)Taishan Scholar Engineering Construction Fund of Shandong Province of China(J06N04)
文摘Coal bump is a dynamic process,thus it is necessary to reveal the process validly.2D-ball code is an efficient approach developed by the authors based on the basicDEM rationale proposed by Cundall.Numerical simulations show that the coal bump experiencesa process of energy accumulation,sudden release of energy and energy decrease.The stiffness of coal particles has a great influence on the coal bump morphosisand particle velocity.Generally,the larger the stiffness of particles,the longer the shootingoff period and the larger the bump velocity.This is in agreement with the results of laboratoryexperiment and in-situ studies.However,the stiffness of particles has an influence onthe quantity value energy and no influence on the releasing energy pattern of the coalbump.
文摘At present, all aspects of China have entered the era of a rapid development, while the development speed of digital electronic technology is especially outstanding. This is a new way for China' s new personnel training, and also proposes higher requirements on this type of personnel training institutions. In view of the demands of society and different majors on personnel, an enhancement to the standardized management of electronic laboratory operations becomes one of the important tasks for personnel training institutions. In this paper, how to practice the standardization management in an all-round way is discussed centered at college and university students' electronic laboratory.
基金Supported by the US Agency for International Development(USAID)cooperation agreement(486-A-00-06-000140-00)
文摘Elemental mercury(Hg^0)re-emissions from slurries and solutions were evaluated in a lab-scale simulated scrubber.Oxidized mercury(Hg^2 +)standard solution was injected into the simulated scrubber at a desired rate to simulate absorbing and dissolving of Hg^2 +in the flue gas across wet flue gas desulfurization(WFGD)systems. PS analytical mercury analyzer was used to continuously determine Hg0re-emission concentrations in the carrier gas from the scrubber.Sulfite ion in the slurry of CaSO3 was validated to reduce Hg ^2+to Hg^ 0,while no Hg ^0 re-emission occurred from slurries of CaSO4 and CaO.Transitional metal ions with low chemical valence such as Fe^2 +,Pb ^2+,Ni ^2+, AsO2^-and Cu ^+were used to prepare solutions with concentration levels of mmol·L^-1.Reduction reaction of Hg^2 +to Hg 0was observed from these solutions.Reduction capabilities for the different transitional metal ions in the solutions were:Pb^2 +〉Cu ^+〉Fe^ 2+〉 AsO2^-〉Ni ^2+.
基金sponsored by the National Natural Science Foundation of China(Grant No.41074103) the National Key Fundamental R&D Project(Grant No.2007CB209601) the China National Petroleum Cooperation Fundamental Research Program(Grant No.06A30102)
文摘Clay has a significant influence on the relationship between resistivity index I and water saturation Sw (i.e, I-Sw relationship) of reservoir rocks because it complicates the current paths of these rocks. It is difficult to reveal the physical mechanisms of these clay effects on the conductivities of various rocks by physical laboratory measurements because the pore structure, micro distribution and content of clay inside a rock can not be observed and controlled during the experiments. We present a digital rock approach to study these clay effects on the electrical transport properties of reservoir rocks at pore scale using lattice gas automation (LGA) method. The digital rock samples are constructed with the information of grain size distribution from SEM images of reservoir rocks. The LGA is then applied on these digital rocks fully saturated with fluids to simulate the electrical transport properties for revealing the effects of volume and distribution patterns of clay on the non-Archie behaviors of the I-Sw relationship. The very good agreement between the simulated results and the laboratory measurements clearly demonstrates the validity of the LGA in numerical research of rock physics. Based on these studies, a new model has been developed for quantitatively describing the relationship between the saturation exponent and the volume of clay (Vsh). This development may improve the evaluation for the fluid saturations in reservoir rocks.
文摘Objective: To study the distribution of I_ Ca,L in endomyocardium(Endo), mid-myocardium(Mid) and epicardium(Epi) in female and male rabbit ventricle and to elucidate the mechanism of sex difference in drug-associated torsade de pointes. Methods: Whole-cell patch clamp technique was used to record action potential and I_Ca,L. Results: Action potential duration ofMidinfemale rabbit heart waslonger thanthat in male and transmural dispersion of repolarization in female was largerthan thatinmale. The densities of I_ Ca,L in Endo, Mid and Epi of female rabbits were (7.1±0.6), (10.4±0.9) and (9.6±1.1) pA/pF and they were (9.1±0.9), (10.5±1.0) and (9.8±0.9) pA/pF in male respectively. Transmural heterogeneity of I_ Ca,L in female ventricle was more significant than that in male rabbit.Conclusion:Female rabbitspossessmoresignificant transmural heterogeneityof I_Ca,L,whichmaybe responsiblefor largertransmuraldispersion of repolarization and more drug-associated torsade de pointes in female.
文摘This study aims to (1) obtain a pure extract of Sargassumfilipendula fucoxanthin, (2) determine the effect of concentration of fucoxanthin against HeLa cells, and (3) determine the effect of concentration of fucoxanthin against cancer cell lymphocytes. The benefit of this research is to find out that fucoxanthin can be used as an anti-cancer treatment. The study was conducted in September 2013 at the Laboratory of Fishery Product Technology FPIK UB and UB Medical Biomedical Laboratories, Malang. Sampling brown seaweed (Sargassum filipendula) of the District Rural Padike Talango Sumenep Madura. Extracted isolated by column chromatography using silica gel stationary phase and mobile phase hexane:ethyl acetate (6:4, v/v) ± 100 mL, then identified by TLC using the stationary phase, a silica gel F-254 HPLC with ODS stationary phase (C-18) 5 mL with a mobile phase of methanol, acetone and ammonium acetate (IM) (80:10:10, v/v) and a flow rate of 1.0 mL/min pigment solution of 20 mL compared with the standard of Japan. Research results indicate that, spectra maximum wavelength of 450 nm and 446 nm with a minimum of acetone solvent. HPLC has the same retention time = 10.12 standard, namely Sargassum filipendula = 10.11. By giving some of the best concentrations at 100 ppm is lethal HeLa cells ebesar 5236% which means that fucoxanthin effect against HeLa cells have the potential fucoxanthin that can induce cell apoptosis that occurs in HeLa cells, it is possible because of the anti-carcinogenic fucoxanthin mempuyai structure unique. While the cell lymphocytes in the dosage of 100 ppm were dead at 8.788%, the effect of the toxicity of a substance can be observed from how many dead lymphocytes when compared with the state charity by observing level of lymphocyte proliferation.
文摘Despite the developments of sectors which aim at valorizing recyclable materials, landfills remain essential in integrated waste management. The construction of such infrastructures is an engineering challenge that must be proven over the long term. The purpose of this study is to understand the modification of the hydromechanical properties of bottom liners of landfills that may occur during their exploitation under leachate action. To do so, on the basis of its parameters of nature, a swelling clay from Burkina Faso is selected from soils of seven localities in Burkina Faso (West Africa). Laboratory tests carried out with distilled water and then with a young synthetic leachate show a degradation of the permeability of this clay from 2.42 × 10^-10 m/s to 1.01 × 10^-9 m/s. In addition, leachate leads to an inhibition of the swelling and a remarkable increase of its compressibility, inducing significant settlement. With the increase in permeability, the primary consolidation settlement is increasing faster. Changes in the hydromechanical behavior can be attributed to the clays mineralogy, mainly cation exchange and the development of the diffuse double layer.
文摘In order to investigate the likely allelopathic potential of an aqueous extract and powder of Achillea (,4chillea santolina) on the germination and seedling growth of pea (Cicer arietinum), safflower (Carthamus tinctorius L.) and wheat (Triticum sativum), an experiment was carried out at the laboratory and greenhouse of agriculture faculty of Sho3hid Bahonar University of Kerman, Iran, from October 2009 to March 2010. A completely randomized design with three replicates using five extract concentrations of achillea plant including 0, 25, 50, 75, and 100 g Ll and four amounts of powder of it including 0, 7.5, 15 and 30 g kg1 of soil was employed in laboratory and greenhouse experiments, respectively. All extract concentrations of achillea except 25 g Ll inhibited pea and wheat seed germination significantly, but had no inhibitory effect on the germination of safflower, The powder of mature achillea plants affected the fresh and dry weight and shoots length in these crops negatively compared with the control in all levels. Therefore use of this plant should be prevented in rotation or intercropping with these three crop plants. Further research conducted in the analytical laboratory as well as in the field is needed before a practical application of the extract and powder as weed inhibiting agent can be recommended.
文摘This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space.
文摘The aim of this paper is to establish LIMS (laboratory information management system) for the tea pesticides analysis accredited laboratories in Taiwan. The LIMS could help Tungting station and Nantou pesticide inspection station to computerize the pesticide analysis data. It has completed eight management subsystems so far, including the basic information management subsystem, thesample processing management subsystem, the analysis data management subsystem, the analysis report management subsystem, the inspection standard management subsystem, the instrument connection management subsystem, the laboratory personnel training management subsystem and the laboratory quality document management subsystem. Using the automatic tea pesticide analysis information management system could help laboratory operations to reduce the amount of excess paperwork and human resource, which could ensure the analysis data quality is traceable and reliable.
文摘Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed active switching technology,they successfully conducted the world's longest-more than 90km-round-robin differential phase shift(RRDPS)quantum key distribution experiment.
文摘Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic plants by Callosciurus erythraeus introduced in the Pampas Region of Argentina. We identified and characterized entire and damaged seeds found in squirrel faeces and evaluated the germination capacity and viability of entire seeds in laboratory assays. We collected 120 samples of squirrel faeces that contained 883 pellets in seasonal surveys conducted between July 2011 and June 2012 at 3 study sites within the main invasion focus of C. erythraeus in Argentina. We found 226 entire seeds in 21% of the samples belonging to 4 species of exotic trees and shrubs. Germination in laboratory assays was recorded for Morus alba and Casuarina sp.; however, germination percentage and rate was higher for seeds obtained from the fruits than for seeds obtained from the faeces. The largest size of entire seeds found in the faeces was 4.2 ~ 4.0 ram, whereas the damaged seeds had at least 1 dimension ≥ 4.7 ram. Our results indi- cated that C. erythraeus can disperse viable seeds of at least 2 species of exotic trees. C. erythraeus predated seeds of other naturalized species in the region. The morphometric description suggested a restriction on the maximum size for the passage of entire seeds through the digestive tract of squirrels, which provides useful information to predict its role as a potential disperser or predator of other species in other invaded communities.
基金Supported by National Natural Science Foundation of China under Grants Nos.61144006,11247294,and 11347142
文摘Protection of entanglement from disturbance of the environment is an essential task marion processing. We examine the validity and limitation of the weak measurement and reversal in quantum infor- (WMR) operation in the protection of distributed entanglement from various decoherence sources. Since the entanglement variation can be investigated analytically for an arbitrarily entangled bipartite pure state under three kinds of typical noisy quantum channels, we show explicitly that the WMR operation indeed helps for protecting distributed entanglement from ampli- tude damping and phase damping, but not for depolarizing. Bxperimental feasibility for testing our results is discussed using current laboratory techniques.
文摘The gas and particle time-averaged velocity rand RMS fluctuation velocity of swirling gas-particle flows in a spouting-cyclone combustor were measured by a hot-ball probe and a conventional LDV system. The results show large velocity slip between the two phases both in tangential and axial directions and high nonisotropic turbulence of the two phases were also observed which is favorable to coal combustion. The particle RMS fluctuation velocity is higher than the gas RMS fluctuation velocity only in some regions of the flow field.
文摘Thyrotoxicosis may present in many ways;severe vomiting as a prominent symptom of thyrotoxicosis is uncommon.In this paper,we report a 24-year-old Chinese male with hyperthyroidism who presented with recurrent severe vomiting.The patient had had intermittent vomiting for seven years and had lost approximately 15 kg of weight.Gastroscopic examinations revealed chronic gastritis and one occasion peptic ulcer.He was treated with antacid and proton pump inhibitors,but his symptoms had no relief.His presenting symptoms suggested hyperthyroidism and were confirmed by laboratory data.After a month of propylthiouracil therapy,his symptoms were relieved.It should be noted that hyperthyroidism patients can have unexplained vomiting,and that hyperthyroidism may coexist with peptic ulcer in rare cases.Awareness of such atypical presentations of hyperthyroidism may help to make a correct diagnosis.
基金supported by the National Natural Science Foundation of China(Grant Nos.11490563,11375269 and 11321064)the National Key Basic Research Development Program(Grant No.2013CB834406)
文摘The observation of 26Al is an useful tool for γ-ray astronomy and in studies of galactic chemical evolution. The most likely mechanism for 26Al nucleosynthesis is in the hydrogen burning MgAI cycle, and the 26Al production reaction 25Mg(p, γ)26Al at the important temperature range below T = 0.2 GK is still not well known. The spectroscopic factor of 58 keV resonance level in 26Al is determined with shell model calculation and then used to deduce the resonance strength of the 25Mg(p, γ)26Al reaction. The result provides a reference for the future 25Mg(p, γ)26Al direct measurement at Jinping underground laboratory.
基金supported by the National Natural Science Foundation of China(11805161,12005180,and 11975195)the Natural Science Foundation of Shandong Province(ZR2020QA083 and ZR2019JQ04)the Project of Shandong Province Higher Educational Science and Technology Program(2019KJJ007)。
文摘We study a minimal extension of the standard model by introducing three right-handed neutrinos and a new scotogenic scalar doublet,in which the mass splittings between neutral and charged components are responsible for the W-boson mass newly measured by the CDF Collaboration.This model can not only generate non-vanishing Majorana neutrino masses via the interaction of right-handed neutrinos and scotogenic scalars,but also explain the Universe’s missing matter in the form of FIMP dark matter.We also study the influence of the mass splitting on the first order electroweak phase transition,and find that it can further enhance the transition strength and thus induce gravitational waves during the phase transition,which may be detected in the forthcoming detectors such as U-DECIGO.
基金supported by the National Natural Science Fundation of China(Grant Nos.1110510611375144&11275153)
文摘Recently, Sandia Laboratories developed a neutron scatter camera to detect special nuclear materials. This camera exhibits the following advantages: high efficiency, direction discrimination, neutron-gamma discrimination ability, and wide field of view. However, using the direct projection method, the angular resolution of this camera is limited by uncertainties in the energies estimated from pulse height and time of flight measurements. In this study, we established an eight-element neutron scatter camera and conducted the experiment with a ^(252)Cf neutron source. The results show that it has an angular resolution better than 8°(1s) and a detection efficiency of approximately 2.6′10-4. Using maximum likelihood expectation maximization method, the image artifact was eliminated, and the angular resolution was improved. We proposed an average scattering angle method to estimate the scattering energy of neutrons and Compton gamma rays. As such, we can obtain a recognizable image and energy spectrum of the source with some degradation of energy and image resolutions. Finally, a newly measured light response function based on the MPD^(-4) device was used for image reconstruction. Although we did not obtain a better result than that of the standard light response function, we have observed the effects of light response function on image reconstruction.