In order to study the response of collision speed caused by the large bus to new flexible barrier,in this paper,with the large bus as the carrier,the full-scale impact tests between flexible barrier and vehicle with t...In order to study the response of collision speed caused by the large bus to new flexible barrier,in this paper,with the large bus as the carrier,the full-scale impact tests between flexible barrier and vehicle with the impact velocities of 40 km/h and 60 km/h were carried out separately,following the procedures of the test preparation,test processing,data acquisition, etc,which were based on the test platform of the Large Structure Crash Testing Laboratory of Changsha University of Science and Technology. The important test results which contain the damage of vehicles and barrier,the moving locus of vehicle,the occupant risk index,the maximum dynamic deformation, etc,were obtained through the analysis under the different collision speeds. These provide the necessary reference basis for the further research on the structure topology optimization and improve the comprehensive constraint performance to the flexible barrier.展开更多
The effects of trace element Fe on the corrosion behavior of AZ80 magnesium alloy were investigated by salt spray test and electrochemical measurements.The results show that the corrosion rate decreases with decreasin...The effects of trace element Fe on the corrosion behavior of AZ80 magnesium alloy were investigated by salt spray test and electrochemical measurements.The results show that the corrosion rate decreases with decreasing the trace element Fe content in an approximately linear relation even though the amount of trace element Fe reduces to 0.000 2%(mass fraction).The electrochemical measurements show that the corrosion potential(φcorr)of the alloy with lower trace element Fe content shifts to less negative value.It is suggested that the control trace element by purification is an effective way to enhance the corrosion resistance of AZ80 magnesium alloy.展开更多
The degradation behavior of aggregate skeleton in stone matrix asphalt mixture was investigated based on theoretical analysis, laboratory test and field materials evaluation. A stress-transfer model was established to...The degradation behavior of aggregate skeleton in stone matrix asphalt mixture was investigated based on theoretical analysis, laboratory test and field materials evaluation. A stress-transfer model was established to provide the fundamental understanding of the stress distribution and degradation mechanism of stone matrix asphalt (SMA) aggregate skeleton. Based on the theoretical analysis, crushing test and superpave gyratory compactor (SGC) test were used to evaluate the degradation behavior of aggregate skeleton of SMA. To verify the laboratory test results, gradation analysis was also conducted for the field materials extracted from SMA pavements after long-time service. The results indicate that the degradation of SMA aggregate skeleton is not random but has fixed internal trend and mechanism. Special rule is found for the graded fine aggregates generated from coarse aggregate breakdown and the variation of 4.75 mm aggregate is found to play a key role in the graded aggregates to form well-balanced skeleton to bear external loading. The variation of 4.75 mm aggregate together with the breakdown ratio of aggregate gradation can be used to characterize the degradation behavior of aggregate skeleton. The crushing test and SGC test are proved to be promising in estimating the degradation behavior of SMA skeleton.展开更多
Because of the complication of turbulence's mechanism and law as well as the jet pressure in nozzle is difficult to test by experiment, five turbulent models were applied to numerically simulate the turbulent flow fi...Because of the complication of turbulence's mechanism and law as well as the jet pressure in nozzle is difficult to test by experiment, five turbulent models were applied to numerically simulate the turbulent flow field in convergent-divergent nozzle. Theory analysis and experiment results of mass flow rates conclude that the RNG k-ε model is the most suitable model. The pressure distribution in the convergent-divergent nozzle was revealed by computational fluid dynamic (CFD) simulating on the turbulent flow field under different pressure conditions. The growing conditions of cavitation bubbles were shown; meanwhile, the phenomena in the experiment could be explained. The differential pres- sure between the upstream and downstream in nozzle throat section can improve the cavitating effect of cavitation water jet.展开更多
In order to solve the poor generalization ability of the back-propagation(BP)neural network in the model updating hybrid test,a novel method called the AdaBoost regression tree algorithm is introduced into the model u...In order to solve the poor generalization ability of the back-propagation(BP)neural network in the model updating hybrid test,a novel method called the AdaBoost regression tree algorithm is introduced into the model updating procedure in hybrid tests.During the learning phase,the regression tree is selected as a weak regression model to be trained,and then multiple trained weak regression models are integrated into a strong regression model.Finally,the training results are generated through voting by all the selected regression models.A 2-DOF nonlinear structure was numerically simulated by utilizing the online AdaBoost regression tree algorithm and the BP neural network algorithm as a contrast.The results show that the prediction accuracy of the online AdaBoost regression algorithm is 48.3%higher than that of the BP neural network algorithm,which verifies that the online AdaBoost regression tree algorithm has better generalization ability compared to the BP neural network algorithm.Furthermore,it can effectively eliminate the influence of weight initialization and improve the prediction accuracy of the restoring force in hybrid tests.展开更多
Adopting oil-bath temperature programming experiment and gas chromatography, CO2's inhibitory performance on spontaneous combustion of Tingnan Coal Mine sample was analyzed. Through temperature rise rate test experim...Adopting oil-bath temperature programming experiment and gas chromatography, CO2's inhibitory performance on spontaneous combustion of Tingnan Coal Mine sample was analyzed. Through temperature rise rate test experiment, the accuracy, stability and reliability of the improved oil-bath temperature programming system applied in this experiment was proved to be superior to the traditional system. Spontaneous combustion characters parameters test of coal sample in pure air was carried out with this system and offered comparison standard for research in next stage. Temperature programming to coal sample was further conducted in oil-bath with different concentration of CO2. Testing results are compared with parameters of concentration of CO, O2, temperature, CO generation rate and O2 consumption rate tested and calculated in previous experiment in pure air. Methods of proportioning between concentration of CO and O2, CO concentration and temperature, CO generation rate and O2 consumption rate were applied to eliminate obstructions from certain external factors such as inlet of CO2; meanwhile influences of CO2 of different concentrations to coal oxidation and spontaneous combustion were investigated. Also CO2 inhibition technique was used in spontaneous combustion prevention in workface No. 106 of Tingnan Coal Mine, data collected from which indicate that CO2 performs well in inhibiting coal oxidation and spontaneous combustion.展开更多
Appropriate base oils and homologous additives such as extreme pressure and anti-wear agents,oiliness agents and antioxidants were selected,and experiments testing the compatibility performance between additive,base o...Appropriate base oils and homologous additives such as extreme pressure and anti-wear agents,oiliness agents and antioxidants were selected,and experiments testing the compatibility performance between additive,base oil and other components were carried out to develop the SK and SD series of rolling oils for cold rolling of stainless steel.The developed oils were used in the stainless steel cold rolling lubrication experiments,and were successfully applied in the actual cold rolling operation of stainless steel.Compared with a foreign product,the tribological properties,the thermal oxidation stability,and the rolling lubrication performance of the developed stainless steel cold rolling oils were studied.Test results showed that the tribological properties of the thereby developed rolling oils and the reference one were almost at the same level,and to some extent the performance of rolling was even better than the foreign product,at the same time the stainless steel sheet could retain its well annealed performance.Meanwhile,within a certain range,the lubrication of the rolling oil became better as its viscosity increased at the same level of saponification value,which could provide a lower friction coefficient,so that a higher maximum reduction ratio of the rolled piece through a constant roll gap and a minimum thickness could be secured.Also,similar phenomena appeared as the saponification value increased at a same viscosity level of the rolling oils.展开更多
The coal of Anyuan Mine has the characteristic of easy spontaneous combustion. Conventional method is difficult to predict it. Coal samples from this mine were tested in laboratory. The data obtained from laboratory d...The coal of Anyuan Mine has the characteristic of easy spontaneous combustion. Conventional method is difficult to predict it. Coal samples from this mine were tested in laboratory. The data obtained from laboratory determination were initialized for the value which was defined as "K". The ratio of each index gas and value of "K", and the ratio of combination index gases and value of "K", were analyzed simultaneously. The research results show that for this coal mine, if there is carbon monoxide in the gas sample, the phenomenon of oxidation and temperature rising for coal exists in this mine; if there is C_2H_4 in the gas sample, the temperature of coal perhaps exceeds 130 °C. If the coal temperature is between 35 °C and 130 °C, prediction and forecast for coal spontaneous combustion depend on the value of Φ(CO)/K mainly; if the temperature of coal is between 130 °C and 300 °C, prediction and forecast for coal spontaneous combustion depend on the value of Φ(C_2H_6)/Φ(C_2H_2) and Φ(C_2H_6)/K. The research results provide experimental basis for the prediction of coal spontaneous combustion in Anyuan coal mine, and have better guidance on safe production of this coal mine.展开更多
Objective: To observe the electrocardiogram (ECG) and heart rate in a rabbit model ofhyperkalemia induced by potassium chloride, and provide theoretical and experimental reference for timely diagnosis of hyperkalem...Objective: To observe the electrocardiogram (ECG) and heart rate in a rabbit model ofhyperkalemia induced by potassium chloride, and provide theoretical and experimental reference for timely diagnosis of hyperkalemia clinically. Methods: Forty rabbits were randomly assigned into four groups. 0.9% isotonic saline solution was perfused in the group I , while 1.0%, 4.0% and 10.0% potassium chloride solutions were perfused in the other groups, respectively, to induce hyperkalemia. Results: The changes of serum potassium, ECG and heart rate before perfusion were significantly (P〈 0.05) different from those after perfusion in the other groups compared with group I . The effect of ECG variability rates was well consistent (Kappa = 0.724, P〈0.01) with that of serum potassium on diagnostic tests in the other groups. The area under ROC curve in diagnosis effect of ECG variability rates and sermn potassium on hyperkalaemia was much significantly larger (P〈0.01 and P〈0.05) compared with 0.5. There was asignificantly positive correlation between ECG variability rates and serum potassium (r= 0.865, P〈0.05 for bilateral Pearson test). There was certain positive correlation between heart rate and serum potassium, but the correlation was poor (r= 0.526, R2=0.277). Conclusion: A combination of serum potassium, ECG variability rates and heart rate should be considered and analyzed by synthesis to establish an accurate and timely diagnosis for hyperkalemia.展开更多
Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted i...Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted intensively, should be established with seed high potential physiological and health for the development of a more productive and sustainable agriculture. The present study was conducted to evaluate the potential physiological of seed lots of radish and coriander. The experiment was conducted at the laboratory of seed analysis and greenhouse of the plant science department of the Federal University of Pelotas in South Brazil. Four radish seed lots, cultivar "Saxa", and four coriander seed lots, cultivar "Verdito" were used. Germination seed test, first count of germination, accelerated aging test, electrical conductivity and seedling emergence were used to evaluate the physiological quality of the lots. The experimental design was completely randomized design with five replications. Means were compared by Tukey test. The accelerated aging test was the most efficient test in assessing the physiological quality for both lots of radish seeds and coriander and this test provide coherent results with seedlings emergence.展开更多
A new double-yield-sarface (DYS) model was developed to characterize the strength and deformation behaviors of coarse granular materials (CGMs). Two kinds of deformation mechanisms, including the shear and compres...A new double-yield-sarface (DYS) model was developed to characterize the strength and deformation behaviors of coarse granular materials (CGMs). Two kinds of deformation mechanisms, including the shear and compressive plastic deformation, were taken into account in this model, These two deformation mechanisms were described by the shear and compressive yield functions, respectively. The Lode angle dependent formulations of proposed model were deduced by incorporating a 3D nonlinear unified failure criterion. Some comparisons were presented between the numerical predictions of proposed model and test data of true triaxial tests on the modeled rockfills. The model predictions are in good agreement with the test data and capture the strain hardening and plastic volumetric dilation of CGMs. These findings verify the reasonability of current DYS model, and indicate that this model is well suited to reproduce the stress-strain-volume change behavior of CGMs in general.展开更多
Recently, a novel porcine circovirus-like virus P1 with a circular DNA genome of 0.648 kb was identified. P1 antigen was detected both in vitro and in vivo by synthetic peptide-derived polyclonal antibody-based immuno...Recently, a novel porcine circovirus-like virus P1 with a circular DNA genome of 0.648 kb was identified. P1 antigen was detected both in vitro and in vivo by synthetic peptide-derived polyclonal antibody-based immunochemistry. The designed peptides were synthesized by solid-phase technique, purified by high performance liquid chromatography, coupled to Keyhole limpet hemocyanin, and injected into rabbits to prepare polyclonal antibody. The emergence of positive cells revealed that synthetic peptide could elicit antibodies against P1 and viral protein could be synthesized. The polyclonal peptide antibodies described here was successfully applied to immunochemical staining and proved helpful in diagnosing P1.展开更多
This experiment was carried out to determine feed intake and digestibility of grazing sheep on pasture. A total of 14 animals randomly divided into two groups with seven animals each group were used in the experiment....This experiment was carried out to determine feed intake and digestibility of grazing sheep on pasture. A total of 14 animals randomly divided into two groups with seven animals each group were used in the experiment. Digestibility of pastures was determined using two types of markers-alkane (C32-C36) and chromium oxide. Dry matter intake (DMI) was 717.22 g/d based on chromium oxide method in the experiment, while according to alkane method, DMI was 965.93 g/d and 1,051.07 g/d for C32 and C36, respectively. In conclusion, pastures met 74%-81% of crude protein (CP) and 57%-61% of energy requirements of lambs grazing on Yuzuncu Yil University pasture, who are mid-quality and 4-7 month-old with a 275 g/d expected daily gain. It was calculated that when 628-693 g/d of barley is given, both CP and metabolizable energy (ME) requirements of animals can be met.展开更多
Terms of synthesis were defined for the creation of new generation chelate fertilizers and for their experimental testing. Glutamine acid and citric acid containing chelate citrates of the general formulae M.gI.HL'nH...Terms of synthesis were defined for the creation of new generation chelate fertilizers and for their experimental testing. Glutamine acid and citric acid containing chelate citrates of the general formulae M.gI.HL'nHO were synthesized, where, M = Mn, Zn, Fe, Co, Cu; n = 0; 1; 1.5; gl-glutamine acid; HL-citric acid anion. Identity and composition of synthesized compounds were determined by microelemental analysis, melting temperature and X-ray diffraction analysis. X-ray diffraction analysis of the compounds and glutamine acid and citric acid (H4L) was used to determine their crystalline structure and roentgen-amorphous and iso-structural orders. Their solubility was studied in various solvents.展开更多
This paper presents a method of determining the friction coefficient in metal forming using multilayer artificial neural networks based on experimental data obtained from strip drawing test. The number of input variab...This paper presents a method of determining the friction coefficient in metal forming using multilayer artificial neural networks based on experimental data obtained from strip drawing test. The number of input variables of the artificial neural network has been optimized using genetic algorithm. This process is based on surface parameters of the sheet and dies, sheet material parameters and clamping force as input parameters to train the neural network. In addition to demonstrating the fact that regression statistics model using genetic selection and intelligent problem solver are better than models without preprocessing of input data, the sensitivity analysis of the input variables has been conducted. This avoids the time-consuming testing of neurons in finding the best network architecture. The obtained results from this study have also pointed out that genetic algorithm can successfully be applied to optimize the training set and the outputs agree with experimental results. This allows reduction or elimination of expensive experimental tests to determine friction coefficient value.展开更多
Objective:The aim of this study was to prepare monoclonal antibody against P53, a kind of tumor suppressor protein,and use the antibody initial y in clinical immunoassay. Methods:Monoclonal antibody was prepared and...Objective:The aim of this study was to prepare monoclonal antibody against P53, a kind of tumor suppressor protein,and use the antibody initial y in clinical immunoassay. Methods:Monoclonal antibody was prepared and identified via the classic protocol of monoclonal antibody preparation. Identified monoclonal antibodies were purified by af inity chro-matography. Antibody titer was determined by enzyme linked immunosorbent assay (ELISA). The specific binding activity of antibody was detected by Western blotting and immunohistochemistry. Results:Three strains of monoclonal antibodies named 1P15, 2P37 and 3P40 were obtained and purified by af inity chromatography. The purity of antibodies was higher than 90%. The titers of antibodies were more than 1:6000. Western blot and immunohistochemistry assay showed that the specific antibody can combine with endogenous P53 protein in the tumor celllines and determine the expression of P53 in tumor tis-sue. Conclusion:Three strains of monoclonal antibodies with high af inity to P53 were successful y established, which can be used for detecting the expression of P53 in tumor cells or tissue.展开更多
基金National Natural Science Foundation of China(No.51175050)
文摘In order to study the response of collision speed caused by the large bus to new flexible barrier,in this paper,with the large bus as the carrier,the full-scale impact tests between flexible barrier and vehicle with the impact velocities of 40 km/h and 60 km/h were carried out separately,following the procedures of the test preparation,test processing,data acquisition, etc,which were based on the test platform of the Large Structure Crash Testing Laboratory of Changsha University of Science and Technology. The important test results which contain the damage of vehicles and barrier,the moving locus of vehicle,the occupant risk index,the maximum dynamic deformation, etc,were obtained through the analysis under the different collision speeds. These provide the necessary reference basis for the further research on the structure topology optimization and improve the comprehensive constraint performance to the flexible barrier.
基金Project(2007CB613705)supported by the National Basic Research Program of China
文摘The effects of trace element Fe on the corrosion behavior of AZ80 magnesium alloy were investigated by salt spray test and electrochemical measurements.The results show that the corrosion rate decreases with decreasing the trace element Fe content in an approximately linear relation even though the amount of trace element Fe reduces to 0.000 2%(mass fraction).The electrochemical measurements show that the corrosion potential(φcorr)of the alloy with lower trace element Fe content shifts to less negative value.It is suggested that the control trace element by purification is an effective way to enhance the corrosion resistance of AZ80 magnesium alloy.
基金Project(51008075) supported by the National Natural Science Foundation of ChinaProject(2006AA11Z110) supported by the National High Technology Research and Development Program of China
文摘The degradation behavior of aggregate skeleton in stone matrix asphalt mixture was investigated based on theoretical analysis, laboratory test and field materials evaluation. A stress-transfer model was established to provide the fundamental understanding of the stress distribution and degradation mechanism of stone matrix asphalt (SMA) aggregate skeleton. Based on the theoretical analysis, crushing test and superpave gyratory compactor (SGC) test were used to evaluate the degradation behavior of aggregate skeleton of SMA. To verify the laboratory test results, gradation analysis was also conducted for the field materials extracted from SMA pavements after long-time service. The results indicate that the degradation of SMA aggregate skeleton is not random but has fixed internal trend and mechanism. Special rule is found for the graded fine aggregates generated from coarse aggregate breakdown and the variation of 4.75 mm aggregate is found to play a key role in the graded aggregates to form well-balanced skeleton to bear external loading. The variation of 4.75 mm aggregate together with the breakdown ratio of aggregate gradation can be used to characterize the degradation behavior of aggregate skeleton. The crushing test and SGC test are proved to be promising in estimating the degradation behavior of SMA skeleton.
基金Supported by the National Natural Science Foundation of China (50621403,50604019)Program for New Century Excellent Talents in Univer sity(NCET-06-0767)
文摘Because of the complication of turbulence's mechanism and law as well as the jet pressure in nozzle is difficult to test by experiment, five turbulent models were applied to numerically simulate the turbulent flow field in convergent-divergent nozzle. Theory analysis and experiment results of mass flow rates conclude that the RNG k-ε model is the most suitable model. The pressure distribution in the convergent-divergent nozzle was revealed by computational fluid dynamic (CFD) simulating on the turbulent flow field under different pressure conditions. The growing conditions of cavitation bubbles were shown; meanwhile, the phenomena in the experiment could be explained. The differential pres- sure between the upstream and downstream in nozzle throat section can improve the cavitating effect of cavitation water jet.
基金The National Natural Science Foundation of China(No.51708110)。
文摘In order to solve the poor generalization ability of the back-propagation(BP)neural network in the model updating hybrid test,a novel method called the AdaBoost regression tree algorithm is introduced into the model updating procedure in hybrid tests.During the learning phase,the regression tree is selected as a weak regression model to be trained,and then multiple trained weak regression models are integrated into a strong regression model.Finally,the training results are generated through voting by all the selected regression models.A 2-DOF nonlinear structure was numerically simulated by utilizing the online AdaBoost regression tree algorithm and the BP neural network algorithm as a contrast.The results show that the prediction accuracy of the online AdaBoost regression algorithm is 48.3%higher than that of the BP neural network algorithm,which verifies that the online AdaBoost regression tree algorithm has better generalization ability compared to the BP neural network algorithm.Furthermore,it can effectively eliminate the influence of weight initialization and improve the prediction accuracy of the restoring force in hybrid tests.
文摘Adopting oil-bath temperature programming experiment and gas chromatography, CO2's inhibitory performance on spontaneous combustion of Tingnan Coal Mine sample was analyzed. Through temperature rise rate test experiment, the accuracy, stability and reliability of the improved oil-bath temperature programming system applied in this experiment was proved to be superior to the traditional system. Spontaneous combustion characters parameters test of coal sample in pure air was carried out with this system and offered comparison standard for research in next stage. Temperature programming to coal sample was further conducted in oil-bath with different concentration of CO2. Testing results are compared with parameters of concentration of CO, O2, temperature, CO generation rate and O2 consumption rate tested and calculated in previous experiment in pure air. Methods of proportioning between concentration of CO and O2, CO concentration and temperature, CO generation rate and O2 consumption rate were applied to eliminate obstructions from certain external factors such as inlet of CO2; meanwhile influences of CO2 of different concentrations to coal oxidation and spontaneous combustion were investigated. Also CO2 inhibition technique was used in spontaneous combustion prevention in workface No. 106 of Tingnan Coal Mine, data collected from which indicate that CO2 performs well in inhibiting coal oxidation and spontaneous combustion.
文摘Appropriate base oils and homologous additives such as extreme pressure and anti-wear agents,oiliness agents and antioxidants were selected,and experiments testing the compatibility performance between additive,base oil and other components were carried out to develop the SK and SD series of rolling oils for cold rolling of stainless steel.The developed oils were used in the stainless steel cold rolling lubrication experiments,and were successfully applied in the actual cold rolling operation of stainless steel.Compared with a foreign product,the tribological properties,the thermal oxidation stability,and the rolling lubrication performance of the developed stainless steel cold rolling oils were studied.Test results showed that the tribological properties of the thereby developed rolling oils and the reference one were almost at the same level,and to some extent the performance of rolling was even better than the foreign product,at the same time the stainless steel sheet could retain its well annealed performance.Meanwhile,within a certain range,the lubrication of the rolling oil became better as its viscosity increased at the same level of saponification value,which could provide a lower friction coefficient,so that a higher maximum reduction ratio of the rolled piece through a constant roll gap and a minimum thickness could be secured.Also,similar phenomena appeared as the saponification value increased at a same viscosity level of the rolling oils.
基金Projects(51274099,51474106)supported by the National Natural Science Foundation of China
文摘The coal of Anyuan Mine has the characteristic of easy spontaneous combustion. Conventional method is difficult to predict it. Coal samples from this mine were tested in laboratory. The data obtained from laboratory determination were initialized for the value which was defined as "K". The ratio of each index gas and value of "K", and the ratio of combination index gases and value of "K", were analyzed simultaneously. The research results show that for this coal mine, if there is carbon monoxide in the gas sample, the phenomenon of oxidation and temperature rising for coal exists in this mine; if there is C_2H_4 in the gas sample, the temperature of coal perhaps exceeds 130 °C. If the coal temperature is between 35 °C and 130 °C, prediction and forecast for coal spontaneous combustion depend on the value of Φ(CO)/K mainly; if the temperature of coal is between 130 °C and 300 °C, prediction and forecast for coal spontaneous combustion depend on the value of Φ(C_2H_6)/Φ(C_2H_2) and Φ(C_2H_6)/K. The research results provide experimental basis for the prediction of coal spontaneous combustion in Anyuan coal mine, and have better guidance on safe production of this coal mine.
基金Supported by Natural Science Foundation of Chengdu Medical College(CYZ09-004)The "Challenge Cup" Sichuan Undergraduate Curricular Academic Science and Technology Works(CT11D-1006)
文摘Objective: To observe the electrocardiogram (ECG) and heart rate in a rabbit model ofhyperkalemia induced by potassium chloride, and provide theoretical and experimental reference for timely diagnosis of hyperkalemia clinically. Methods: Forty rabbits were randomly assigned into four groups. 0.9% isotonic saline solution was perfused in the group I , while 1.0%, 4.0% and 10.0% potassium chloride solutions were perfused in the other groups, respectively, to induce hyperkalemia. Results: The changes of serum potassium, ECG and heart rate before perfusion were significantly (P〈 0.05) different from those after perfusion in the other groups compared with group I . The effect of ECG variability rates was well consistent (Kappa = 0.724, P〈0.01) with that of serum potassium on diagnostic tests in the other groups. The area under ROC curve in diagnosis effect of ECG variability rates and sermn potassium on hyperkalaemia was much significantly larger (P〈0.01 and P〈0.05) compared with 0.5. There was asignificantly positive correlation between ECG variability rates and serum potassium (r= 0.865, P〈0.05 for bilateral Pearson test). There was certain positive correlation between heart rate and serum potassium, but the correlation was poor (r= 0.526, R2=0.277). Conclusion: A combination of serum potassium, ECG variability rates and heart rate should be considered and analyzed by synthesis to establish an accurate and timely diagnosis for hyperkalemia.
文摘Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted intensively, should be established with seed high potential physiological and health for the development of a more productive and sustainable agriculture. The present study was conducted to evaluate the potential physiological of seed lots of radish and coriander. The experiment was conducted at the laboratory of seed analysis and greenhouse of the plant science department of the Federal University of Pelotas in South Brazil. Four radish seed lots, cultivar "Saxa", and four coriander seed lots, cultivar "Verdito" were used. Germination seed test, first count of germination, accelerated aging test, electrical conductivity and seedling emergence were used to evaluate the physiological quality of the lots. The experimental design was completely randomized design with five replications. Means were compared by Tukey test. The accelerated aging test was the most efficient test in assessing the physiological quality for both lots of radish seeds and coriander and this test provide coherent results with seedlings emergence.
基金Project(50825901)supported by the National Natural Science Foundation for Distinguished Young Scholar of ChinaProject(2009492011)supported by State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing Hydraulic Research Institute,China+1 种基金Project(GH200903)supported by Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering(Hohai University),ChinaProject(Y1090151)supported by Natural Science Foundation of Zhejiang Province,China
文摘A new double-yield-sarface (DYS) model was developed to characterize the strength and deformation behaviors of coarse granular materials (CGMs). Two kinds of deformation mechanisms, including the shear and compressive plastic deformation, were taken into account in this model, These two deformation mechanisms were described by the shear and compressive yield functions, respectively. The Lode angle dependent formulations of proposed model were deduced by incorporating a 3D nonlinear unified failure criterion. Some comparisons were presented between the numerical predictions of proposed model and test data of true triaxial tests on the modeled rockfills. The model predictions are in good agreement with the test data and capture the strain hardening and plastic volumetric dilation of CGMs. These findings verify the reasonability of current DYS model, and indicate that this model is well suited to reproduce the stress-strain-volume change behavior of CGMs in general.
基金Supported by National Natural Science Foundation of China(31272574,30972184)
文摘Recently, a novel porcine circovirus-like virus P1 with a circular DNA genome of 0.648 kb was identified. P1 antigen was detected both in vitro and in vivo by synthetic peptide-derived polyclonal antibody-based immunochemistry. The designed peptides were synthesized by solid-phase technique, purified by high performance liquid chromatography, coupled to Keyhole limpet hemocyanin, and injected into rabbits to prepare polyclonal antibody. The emergence of positive cells revealed that synthetic peptide could elicit antibodies against P1 and viral protein could be synthesized. The polyclonal peptide antibodies described here was successfully applied to immunochemical staining and proved helpful in diagnosing P1.
文摘This experiment was carried out to determine feed intake and digestibility of grazing sheep on pasture. A total of 14 animals randomly divided into two groups with seven animals each group were used in the experiment. Digestibility of pastures was determined using two types of markers-alkane (C32-C36) and chromium oxide. Dry matter intake (DMI) was 717.22 g/d based on chromium oxide method in the experiment, while according to alkane method, DMI was 965.93 g/d and 1,051.07 g/d for C32 and C36, respectively. In conclusion, pastures met 74%-81% of crude protein (CP) and 57%-61% of energy requirements of lambs grazing on Yuzuncu Yil University pasture, who are mid-quality and 4-7 month-old with a 275 g/d expected daily gain. It was calculated that when 628-693 g/d of barley is given, both CP and metabolizable energy (ME) requirements of animals can be met.
基金We thank Science & Technology Center in Ukraine and Shota Rustaveli National Science Foundation. The work was implemented with the support of Science & Technology Center in Ukraine Project Proposal #5461 and Shota Rustaveli National Science Foundation Grant #30/06.
文摘Terms of synthesis were defined for the creation of new generation chelate fertilizers and for their experimental testing. Glutamine acid and citric acid containing chelate citrates of the general formulae M.gI.HL'nHO were synthesized, where, M = Mn, Zn, Fe, Co, Cu; n = 0; 1; 1.5; gl-glutamine acid; HL-citric acid anion. Identity and composition of synthesized compounds were determined by microelemental analysis, melting temperature and X-ray diffraction analysis. X-ray diffraction analysis of the compounds and glutamine acid and citric acid (H4L) was used to determine their crystalline structure and roentgen-amorphous and iso-structural orders. Their solubility was studied in various solvents.
文摘This paper presents a method of determining the friction coefficient in metal forming using multilayer artificial neural networks based on experimental data obtained from strip drawing test. The number of input variables of the artificial neural network has been optimized using genetic algorithm. This process is based on surface parameters of the sheet and dies, sheet material parameters and clamping force as input parameters to train the neural network. In addition to demonstrating the fact that regression statistics model using genetic selection and intelligent problem solver are better than models without preprocessing of input data, the sensitivity analysis of the input variables has been conducted. This avoids the time-consuming testing of neurons in finding the best network architecture. The obtained results from this study have also pointed out that genetic algorithm can successfully be applied to optimize the training set and the outputs agree with experimental results. This allows reduction or elimination of expensive experimental tests to determine friction coefficient value.
基金Supported by grants from the National Natural Science Foundation of China(No.30973562)National Basic Research Program of China(No.2010CB933904)
文摘Objective:The aim of this study was to prepare monoclonal antibody against P53, a kind of tumor suppressor protein,and use the antibody initial y in clinical immunoassay. Methods:Monoclonal antibody was prepared and identified via the classic protocol of monoclonal antibody preparation. Identified monoclonal antibodies were purified by af inity chro-matography. Antibody titer was determined by enzyme linked immunosorbent assay (ELISA). The specific binding activity of antibody was detected by Western blotting and immunohistochemistry. Results:Three strains of monoclonal antibodies named 1P15, 2P37 and 3P40 were obtained and purified by af inity chromatography. The purity of antibodies was higher than 90%. The titers of antibodies were more than 1:6000. Western blot and immunohistochemistry assay showed that the specific antibody can combine with endogenous P53 protein in the tumor celllines and determine the expression of P53 in tumor tis-sue. Conclusion:Three strains of monoclonal antibodies with high af inity to P53 were successful y established, which can be used for detecting the expression of P53 in tumor cells or tissue.