In this paper,experimental and numerical studies of heat transfer in a test local of side H=0.8 m heated from below are presented and compared.All the walls,the rest of the floor and the ceiling are made from plywood ...In this paper,experimental and numerical studies of heat transfer in a test local of side H=0.8 m heated from below are presented and compared.All the walls,the rest of the floor and the ceiling are made from plywood and polystyrene in sandwich form(3 mmplywood-3 cm polystyrene-3 mmplywood)just on one of the vertical walls contained a glazed door(2 H/3×0.15 m).This local is heated during two heating cycles by a square plate of iron the width L=0.6 H,which represents the heat source,its temperature Th is controlled.The plate is heated for two cycles by an adjustable set-point heat source placed just down the center of it.For each cycle,the heat source is switched“on”for 6 h and switched“off”for 6 h.The outdoor air temperature is kept constant at a low temperature Tc<Th.All measurements are carried out with k-type thermocouples and with flux meters.Results will be qualitatively presented for two cycles of heating in terms of temperatures and heat flux densitiesϕfor various positions of the test local.The temperature evolution of the center and the profile of the temperature along the vertical centerline are compared by two dimensions simulation using the lattice Boltzmann method.The comparison shows a good agreement with a difference that does not exceed±1℃.展开更多
A rapid and sensitive method for quantitative determination of paclitaxel in rat plasmawas developed and validated by using ultra-performance liquid chromatography-tandemmass spectrometry (UPLC-MS/MS). Docetaxel was u...A rapid and sensitive method for quantitative determination of paclitaxel in rat plasmawas developed and validated by using ultra-performance liquid chromatography-tandemmass spectrometry (UPLC-MS/MS). Docetaxel was used as an internal standard anddiethyl ether was the liquideliquid extraction agent. Multiple reaction monitoring (MRM)mode via positive electrospray ionization (ESI) was applied to detect paclitaxel and IS at thetransitions m/z 854 / 286 and m/z 808.48 / 527.3, respectively. This method covered alinearity range from 5 to 5000 ng/ml, with the total run time of 3.0 min. In summary, a highthroughout UPLC-MS/MS method was successfully developed to measure paclitaxel in ratplasma and was applied to pharmacokinetic study after intravenous administration ofpaclitaxel.展开更多
The luminophors MeO-SiO_2:Eu^(3+),Bi^(3+)and MeO-SiO_2Bi^(3+)(Me=Mg.Sr)were synthesized at relatively lower temperature by the sol-gel method using the silica sol as a source of silica.The optimum composition and synt...The luminophors MeO-SiO_2:Eu^(3+),Bi^(3+)and MeO-SiO_2Bi^(3+)(Me=Mg.Sr)were synthesized at relatively lower temperature by the sol-gel method using the silica sol as a source of silica.The optimum composition and synthesis conditions were obtained by studying the excitation and emission spectra and the effects of energy transfer from the Bi^(3+)ions to the Eu^(3+)ions.展开更多
In college badminton teaching,teachers utilize the group cooperative learning method,which not only helps to improve students’badminton skill level but also cultivates their teamwork spirit,communication skills,and s...In college badminton teaching,teachers utilize the group cooperative learning method,which not only helps to improve students’badminton skill level but also cultivates their teamwork spirit,communication skills,and self-management ability unconsciously.In view of this,this paper mainly describes the significance of applying the group cooperative learning method in college badminton teaching,analyzes the current problems in college badminton teaching,and aims to discover effective development strategies for group cooperative learning method in college badminton teaching in order to improve the effectiveness of college badminton teaching.展开更多
The aim of the proposed research work was to develop and validate a simple, selective high sensitive and high-throughput assay for the simultaneous estimation of Atorvastatin and Glimepiride in human plasma using liqu...The aim of the proposed research work was to develop and validate a simple, selective high sensitive and high-throughput assay for the simultaneous estimation of Atorvastatin and Glimepiride in human plasma using liquid chromatography tandem mass spectrometry (LC-MS/MS). Atorvastatin–Glimepiride combines a competitive inhibitor of HMG-CoA reductase and a sulfonylurea anti-diabetic drug. The purpose of this study was to develop single method for Atorvastatin and Glimepiride in plasma by liquid chromatography-tandem mass spectrometry (LC-MS/MS) that would result into a simultaneous estimation of Atorvastatin and Glimepiride avoiding acid –lactone inter conversions right from sample collections to analysis on the LC-MS/MS. Sample collection procedure optimized for Atorvastatin holds good for Glimepiride, hence resulting into a simultaneous estimation of Atorvastatin and Glimepiride. Liquid-liquid extraction and liquid chromatography coupled to positive ion mode tandem mass spectrometry was used to develop the method and was validated according to US FDA guidelines. The calibration curves for two analytes were linear (R2 ≥ 0.9950, n = 4) over the concentration range of 0.2 - 30 ng/mL for Atorvastatin and 1 - 250 ng/mL for Glimepiride. Mean extraction recoveries 80.34 ± 9.43 for Atorvastatin and 88.19 ± 7.13 for Glimepiride. Intra- and inter-run mean percent accuracy was between 85% - 115% and percent imprecision was ≤15%. Stability studies revealed that Atorvastatin and Glimepiride were stable in plasma during bench top (10.5 h at room temperature), in Injector (47.5 h), at the end of three successive freeze and thaw cycles and long term at -65℃ ± 15℃ for 114 days. The method was successfully applied to the study of pharmacokinetics of Atorvastatin and Glimepiride in healthy volunteers. Simultaneous estimation of Atorvastatin and Glimepiride is cost effective, reduces analysis cycle time, enables effective utilization of resources and reduces bleeding burden on human volunteers.展开更多
Mineral exploration is done by different methods. Geophysical and geochemical studies are two powerful tools in this field. In integrated studies, the results of each study are used to determine the location of the dr...Mineral exploration is done by different methods. Geophysical and geochemical studies are two powerful tools in this field. In integrated studies, the results of each study are used to determine the location of the drilling boreholes. The purpose of this study is to use field geophysics to calculate the depth of mineral reserve. The study area is located 38 km from Zarand city called Jalalabad iron mine. In this study, gravimetric data were measured and mineral depth was calculated using the Euler method. 1314 readings have been performed in this area. The rocks of the region include volcanic and sedimentary. The source of the mineralization in the area is hydrothermal processes. After gravity measuring in the region, the data were corrected, then various methods such as anomalous map remaining in levels one and two, upward expansion, first and second-degree vertical derivatives, analytical method, and analytical signal were drawn, and finally, the depth of the deposit was estimated by Euler method. As a result, the depth of the mineral deposit was calculated to be between 20 and 30 meters on average.展开更多
Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with ...Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with BSYS recipe (consisted of 11 Chinese herbal drugs as Dogwood fruit, Fleeceflower root, prepared Rehmannia root and turtle shell, etc.) orally taken, 3 times per day, 10 g/time, 3 months as one therapeutic course. Hemoglobin (Hb), red blood cell (RBC), reticulocyte (Ret) and hemoglobin F (HbF) were checked every month. At the same time, PAGE, PVR, PCR-SSCP, RT-PCR, DNA series analysis, mRNA gene expression analysis techniques were used to conduct the systematic gene analysis in patients to study the molecular mechanism of TCM treatment from aspects of gene mutation, gene expression and control-regulation. Results: All the blood criteria in patients after BSYS treatment were improved significantly with clinical symptoms展开更多
This is a numerical study of a falling droplet surrounding by air under the electric field modeled with finite volume method by means of CFD.The VOF method has been employed to model the two-phase flow of the present ...This is a numerical study of a falling droplet surrounding by air under the electric field modeled with finite volume method by means of CFD.The VOF method has been employed to model the two-phase flow of the present study.Various capillary numbers are investigated to analyze the effects of electric field intensity on the falling droplet deformation.Also,the effects of electric potential on the heat transfer coefficient have been examined.The obtained results showed that by applying the electric field at a capillary number of 0.2 the droplet tends to retain its primitive shape as time goes by,with a subtle deformation to an oblate form.Intensifying the electric field to a capillary number of 0.8 droplet deformation is almost insignificantwith time progressing;however,further enhancement in capillary number to 2 causes the droplet to deform as a prolate shape and higher values of this number intensify the prolate form deformation of the droplet and result in pinch-off phenomenon.Ultimately,it is showed that as the electric potential augments the heat transfer coefficient increases in which for electric potential values higher than 2400 V the heat transfer coefficient enhances significantly.展开更多
A stability indicating LC method was developed for the simultaneous determination of Amlodipine and Benazepril capsules in pharmaceutical dosage form. Efficient chromatographic separation was achieved on Symmetry C18 ...A stability indicating LC method was developed for the simultaneous determination of Amlodipine and Benazepril capsules in pharmaceutical dosage form. Efficient chromatographic separation was achieved on Symmetry C18 stationary phase with simple combination of amobile phase containing 750 mL of DI Water, 250 mL of Acetonitrile and 2 mL of Octylamine into suitable container with adjusted pH to 2.50 ± 0.05 with the aid of Ortho phosphoric acid delivered in an isocratic mode and quantification was carried out using UV detection at 240 nm at a flow rate of 1.0 mL·min-1 with an injection volume of 20 μl and ambient column temperature. This method is capable to detect both the drug components of Amlodipine and Benazepril in presence of their degradation products (Amlodipine Imp-A and Benazepril Impurity-C) with a detection level of 0.05%. Amlodipine/Benazepril in their combination drug product were exposed to thermal, photolytic, hydrolytic and oxidative stress conditions, and the samples were analysed. Peak homogeneity data of Amlodipine and Benazeprilis were obtained using PDA detector, in the stressed sample chromatograms, demonstrating the specificity. The method shows excellent linearity over a range of 0.05%-2.0% for Amlodipine, Amlodipine Impurity-A and 0.05%-5.0% for Benazepril and Benazepril Impurity-C. The correlation coefficient for Amlodipine and Benazepril is 1. The relative standard deviation was always less than 2%. The proposed method was found to be suitable and accurate for quantitative determination and the stability study of Amlodipine and Benazepril in pharmaceutical preparations. The developed HPLC method was validated with respect to linearity & range, accuracy, precision and robustness.展开更多
This paper introduces the origin and development of land engineering.Taking the course Introduction to Land Engineering as an example,this paper makes a comparative analysis of the teaching effects of traditional teac...This paper introduces the origin and development of land engineering.Taking the course Introduction to Land Engineering as an example,this paper makes a comparative analysis of the teaching effects of traditional teaching method and task-driven teaching method.The results show that the task-driven teaching method is more suitable for the teaching task of land engineering,the students’learning effect is remarkable,and the degree of realization of teaching goal is high.展开更多
By means of improved overlapping Muffin-Tin X_a method recently developed the ground state ~2and the first excited state ~2Σ^+ of the XBS^+(X=H,F,Cl)cations are studied.The calculated energies are in good agreement w...By means of improved overlapping Muffin-Tin X_a method recently developed the ground state ~2and the first excited state ~2Σ^+ of the XBS^+(X=H,F,Cl)cations are studied.The calculated energies are in good agreement with experiment.The ionization potentials of sulphi- doborons,XBS(X=H,F,Cl,Br)are also computed and compared with photoelectron spectra re- sults.展开更多
Nanometer-sized metal clusters were prepared inside single crystalline MgO films by vacuum co-deposition of metals and MgO. The atomic structure was studied by high-resolution electron microscopy (HREM) and nm-area el...Nanometer-sized metal clusters were prepared inside single crystalline MgO films by vacuum co-deposition of metals and MgO. The atomic structure was studied by high-resolution electron microscopy (HREM) and nm-area electron diffraction. The size of the clusters is ranging from 1 nm to 3 nm without those larger than 5 nm, and most of them have definite epitaxial orientations with the MgO matrix films. The character of the composite films is very much useful for the studies of various kinds of physical properties with anisotroPy. The physical properties such as electric transport, magnetic, optical absorption, sintering and catalytic ones were thus measured on the same samples analyzed by HREM by using high sensitivity apparatus with interest of clarifying the retationship between the atomic structure and physical properties展开更多
The ultimate goal of college personnel training is "comprehensively implementing quality-oriented education and cultivating innovation-oriented personnel". The application of "harmonious teaching method" in the sp...The ultimate goal of college personnel training is "comprehensively implementing quality-oriented education and cultivating innovation-oriented personnel". The application of "harmonious teaching method" in the sports dance teaching of general colleges can help theoretically analyze the teaching process of existing sports dance actions and reveal the main reason for the gap with the goal of "comprehensive harmonious development", and also can verify the theoretical analysis results. Therefore, using teaching experiment method, experiment class and control class were selected for implementing two different teaching methods. Difference T test of small samples average was made on the acquired data for revealing the teaching effect difference between two different teaching methods. The result shows that the difference between two teaching methods was significant. The application of "harmonious teaching method" in the sports dance teaching of physical education of general colleges plays a certain positive role in training the comprehensive and harmonious moral, intellectual and physical developments of college students.展开更多
With the development of the global economy, learning English has become the need of many Chinese. People have created a lot of English study methods such as Crazy English, Special English, Peipei English, Dapao Englis...With the development of the global economy, learning English has become the need of many Chinese. People have created a lot of English study methods such as Crazy English, Special English, Peipei English, Dapao English, and so on. These methods have made a great impact on our English teaching model. Although there are no enough scientific theories in them, we can find the special ways to learn English well especially for English listening and speaking. If you analyze them carefully, you will be surprised to find that they are very helpful to improve your listening and speaking ability, and overcome the affective shock. Following some of these methods, the learners can get more knowledge, be more interested in English, study harder and obtain the achievements easily, while the teachers can improve their teaching according to them. At last, the author points out that if the teachers can use them in class correctly, the ideal result will come out.展开更多
Background To detect and identify mosquitoes using their characteristic high-pitched sound,we have developed a smartphone application,known as the‘HumBug sensor’,that records the acoustic signature of this sound,alo...Background To detect and identify mosquitoes using their characteristic high-pitched sound,we have developed a smartphone application,known as the‘HumBug sensor’,that records the acoustic signature of this sound,along with the time and location.This data is then sent remotely to a server where algorithms identify the species according to their distinctive acoustic signature.Whilst this system works well,a key question that remains is what mechanisms will lead to effective uptake and use of this mosquito survey tool?We addressed this question by working with local communities in rural Tanzania and providing three alternative incentives:money only,short message service(SMS)reminders and money,and SMS reminders only.We also had a control group with no incentive.Methods A multi-site,quantitative empirical study was conducted in four villages in Tanzania from April to August 2021.Consenting participants(n=148)were recruited and placed into one of the three intervention arms:monetary incentives only;SMS reminders with monetary incentives;and SMS reminders only.There was also a control group(no intervention).To test effectiveness of the mechanisms,the number of audio uploads to the server of the four trial groups on their specific dates were compared.Qualitative focus group discussions and feedback surveys were also conducted to explore participants’perspectives on their participation in the study and to capture their experiences of using the HumBug sensor.Results Qualitative data analysis revealed that for many participants(37 out of 81),the main motivation expressed was to learn more about the types of mosquitoes present in their houses.Results from the quantitative empirical study indicate that the participants in the‘control’group switched on their HumBug sensors more over the 14-week period(8 out of 14 weeks)when compared to those belonging to the‘SMS reminders and monetary incentives’trial group.These findings are statistically significant(p<0.05 or p>0.95 under a two-sided z-test),revealing that the provision of monetary incentives and sending SMS reminders did not appear to encourage greater number of audio uploads when compared to the control.Conclusions Knowledge on the presence of harmful mosquitoes was the strongest motive for local communities to collect and upload mosquito sound data via the HumBug sensor in rural Tanzania.This finding suggests that most efforts should be made to improve flow of real-time information back to the communities on types and risks associated with mosquitoes present in their houses.展开更多
文摘In this paper,experimental and numerical studies of heat transfer in a test local of side H=0.8 m heated from below are presented and compared.All the walls,the rest of the floor and the ceiling are made from plywood and polystyrene in sandwich form(3 mmplywood-3 cm polystyrene-3 mmplywood)just on one of the vertical walls contained a glazed door(2 H/3×0.15 m).This local is heated during two heating cycles by a square plate of iron the width L=0.6 H,which represents the heat source,its temperature Th is controlled.The plate is heated for two cycles by an adjustable set-point heat source placed just down the center of it.For each cycle,the heat source is switched“on”for 6 h and switched“off”for 6 h.The outdoor air temperature is kept constant at a low temperature Tc<Th.All measurements are carried out with k-type thermocouples and with flux meters.Results will be qualitatively presented for two cycles of heating in terms of temperatures and heat flux densitiesϕfor various positions of the test local.The temperature evolution of the center and the profile of the temperature along the vertical centerline are compared by two dimensions simulation using the lattice Boltzmann method.The comparison shows a good agreement with a difference that does not exceed±1℃.
基金This work was financially supported from the National Nature Science Foundation of China(No.81173008)from the National Basic Research Program of China(973 Program)No.2009CB930300+1 种基金from Project for Excellent Talents of Liaoning Province(No.LR20110028)from Program for New Century Excellent Talents in University(No.NCET-12-1015).
文摘A rapid and sensitive method for quantitative determination of paclitaxel in rat plasmawas developed and validated by using ultra-performance liquid chromatography-tandemmass spectrometry (UPLC-MS/MS). Docetaxel was used as an internal standard anddiethyl ether was the liquideliquid extraction agent. Multiple reaction monitoring (MRM)mode via positive electrospray ionization (ESI) was applied to detect paclitaxel and IS at thetransitions m/z 854 / 286 and m/z 808.48 / 527.3, respectively. This method covered alinearity range from 5 to 5000 ng/ml, with the total run time of 3.0 min. In summary, a highthroughout UPLC-MS/MS method was successfully developed to measure paclitaxel in ratplasma and was applied to pharmacokinetic study after intravenous administration ofpaclitaxel.
文摘The luminophors MeO-SiO_2:Eu^(3+),Bi^(3+)and MeO-SiO_2Bi^(3+)(Me=Mg.Sr)were synthesized at relatively lower temperature by the sol-gel method using the silica sol as a source of silica.The optimum composition and synthesis conditions were obtained by studying the excitation and emission spectra and the effects of energy transfer from the Bi^(3+)ions to the Eu^(3+)ions.
文摘In college badminton teaching,teachers utilize the group cooperative learning method,which not only helps to improve students’badminton skill level but also cultivates their teamwork spirit,communication skills,and self-management ability unconsciously.In view of this,this paper mainly describes the significance of applying the group cooperative learning method in college badminton teaching,analyzes the current problems in college badminton teaching,and aims to discover effective development strategies for group cooperative learning method in college badminton teaching in order to improve the effectiveness of college badminton teaching.
文摘The aim of the proposed research work was to develop and validate a simple, selective high sensitive and high-throughput assay for the simultaneous estimation of Atorvastatin and Glimepiride in human plasma using liquid chromatography tandem mass spectrometry (LC-MS/MS). Atorvastatin–Glimepiride combines a competitive inhibitor of HMG-CoA reductase and a sulfonylurea anti-diabetic drug. The purpose of this study was to develop single method for Atorvastatin and Glimepiride in plasma by liquid chromatography-tandem mass spectrometry (LC-MS/MS) that would result into a simultaneous estimation of Atorvastatin and Glimepiride avoiding acid –lactone inter conversions right from sample collections to analysis on the LC-MS/MS. Sample collection procedure optimized for Atorvastatin holds good for Glimepiride, hence resulting into a simultaneous estimation of Atorvastatin and Glimepiride. Liquid-liquid extraction and liquid chromatography coupled to positive ion mode tandem mass spectrometry was used to develop the method and was validated according to US FDA guidelines. The calibration curves for two analytes were linear (R2 ≥ 0.9950, n = 4) over the concentration range of 0.2 - 30 ng/mL for Atorvastatin and 1 - 250 ng/mL for Glimepiride. Mean extraction recoveries 80.34 ± 9.43 for Atorvastatin and 88.19 ± 7.13 for Glimepiride. Intra- and inter-run mean percent accuracy was between 85% - 115% and percent imprecision was ≤15%. Stability studies revealed that Atorvastatin and Glimepiride were stable in plasma during bench top (10.5 h at room temperature), in Injector (47.5 h), at the end of three successive freeze and thaw cycles and long term at -65℃ ± 15℃ for 114 days. The method was successfully applied to the study of pharmacokinetics of Atorvastatin and Glimepiride in healthy volunteers. Simultaneous estimation of Atorvastatin and Glimepiride is cost effective, reduces analysis cycle time, enables effective utilization of resources and reduces bleeding burden on human volunteers.
文摘Mineral exploration is done by different methods. Geophysical and geochemical studies are two powerful tools in this field. In integrated studies, the results of each study are used to determine the location of the drilling boreholes. The purpose of this study is to use field geophysics to calculate the depth of mineral reserve. The study area is located 38 km from Zarand city called Jalalabad iron mine. In this study, gravimetric data were measured and mineral depth was calculated using the Euler method. 1314 readings have been performed in this area. The rocks of the region include volcanic and sedimentary. The source of the mineralization in the area is hydrothermal processes. After gravity measuring in the region, the data were corrected, then various methods such as anomalous map remaining in levels one and two, upward expansion, first and second-degree vertical derivatives, analytical method, and analytical signal were drawn, and finally, the depth of the deposit was estimated by Euler method. As a result, the depth of the mineral deposit was calculated to be between 20 and 30 meters on average.
文摘Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with BSYS recipe (consisted of 11 Chinese herbal drugs as Dogwood fruit, Fleeceflower root, prepared Rehmannia root and turtle shell, etc.) orally taken, 3 times per day, 10 g/time, 3 months as one therapeutic course. Hemoglobin (Hb), red blood cell (RBC), reticulocyte (Ret) and hemoglobin F (HbF) were checked every month. At the same time, PAGE, PVR, PCR-SSCP, RT-PCR, DNA series analysis, mRNA gene expression analysis techniques were used to conduct the systematic gene analysis in patients to study the molecular mechanism of TCM treatment from aspects of gene mutation, gene expression and control-regulation. Results: All the blood criteria in patients after BSYS treatment were improved significantly with clinical symptoms
文摘This is a numerical study of a falling droplet surrounding by air under the electric field modeled with finite volume method by means of CFD.The VOF method has been employed to model the two-phase flow of the present study.Various capillary numbers are investigated to analyze the effects of electric field intensity on the falling droplet deformation.Also,the effects of electric potential on the heat transfer coefficient have been examined.The obtained results showed that by applying the electric field at a capillary number of 0.2 the droplet tends to retain its primitive shape as time goes by,with a subtle deformation to an oblate form.Intensifying the electric field to a capillary number of 0.8 droplet deformation is almost insignificantwith time progressing;however,further enhancement in capillary number to 2 causes the droplet to deform as a prolate shape and higher values of this number intensify the prolate form deformation of the droplet and result in pinch-off phenomenon.Ultimately,it is showed that as the electric potential augments the heat transfer coefficient increases in which for electric potential values higher than 2400 V the heat transfer coefficient enhances significantly.
文摘A stability indicating LC method was developed for the simultaneous determination of Amlodipine and Benazepril capsules in pharmaceutical dosage form. Efficient chromatographic separation was achieved on Symmetry C18 stationary phase with simple combination of amobile phase containing 750 mL of DI Water, 250 mL of Acetonitrile and 2 mL of Octylamine into suitable container with adjusted pH to 2.50 ± 0.05 with the aid of Ortho phosphoric acid delivered in an isocratic mode and quantification was carried out using UV detection at 240 nm at a flow rate of 1.0 mL·min-1 with an injection volume of 20 μl and ambient column temperature. This method is capable to detect both the drug components of Amlodipine and Benazepril in presence of their degradation products (Amlodipine Imp-A and Benazepril Impurity-C) with a detection level of 0.05%. Amlodipine/Benazepril in their combination drug product were exposed to thermal, photolytic, hydrolytic and oxidative stress conditions, and the samples were analysed. Peak homogeneity data of Amlodipine and Benazeprilis were obtained using PDA detector, in the stressed sample chromatograms, demonstrating the specificity. The method shows excellent linearity over a range of 0.05%-2.0% for Amlodipine, Amlodipine Impurity-A and 0.05%-5.0% for Benazepril and Benazepril Impurity-C. The correlation coefficient for Amlodipine and Benazepril is 1. The relative standard deviation was always less than 2%. The proposed method was found to be suitable and accurate for quantitative determination and the stability study of Amlodipine and Benazepril in pharmaceutical preparations. The developed HPLC method was validated with respect to linearity & range, accuracy, precision and robustness.
基金Supported by Internal Scientific Research Project of Shaanxi Provincial Land Engineering Construction Group(DJNY2019-6).
文摘This paper introduces the origin and development of land engineering.Taking the course Introduction to Land Engineering as an example,this paper makes a comparative analysis of the teaching effects of traditional teaching method and task-driven teaching method.The results show that the task-driven teaching method is more suitable for the teaching task of land engineering,the students’learning effect is remarkable,and the degree of realization of teaching goal is high.
文摘By means of improved overlapping Muffin-Tin X_a method recently developed the ground state ~2and the first excited state ~2Σ^+ of the XBS^+(X=H,F,Cl)cations are studied.The calculated energies are in good agreement with experiment.The ionization potentials of sulphi- doborons,XBS(X=H,F,Cl,Br)are also computed and compared with photoelectron spectra re- sults.
文摘Nanometer-sized metal clusters were prepared inside single crystalline MgO films by vacuum co-deposition of metals and MgO. The atomic structure was studied by high-resolution electron microscopy (HREM) and nm-area electron diffraction. The size of the clusters is ranging from 1 nm to 3 nm without those larger than 5 nm, and most of them have definite epitaxial orientations with the MgO matrix films. The character of the composite films is very much useful for the studies of various kinds of physical properties with anisotroPy. The physical properties such as electric transport, magnetic, optical absorption, sintering and catalytic ones were thus measured on the same samples analyzed by HREM by using high sensitivity apparatus with interest of clarifying the retationship between the atomic structure and physical properties
文摘The ultimate goal of college personnel training is "comprehensively implementing quality-oriented education and cultivating innovation-oriented personnel". The application of "harmonious teaching method" in the sports dance teaching of general colleges can help theoretically analyze the teaching process of existing sports dance actions and reveal the main reason for the gap with the goal of "comprehensive harmonious development", and also can verify the theoretical analysis results. Therefore, using teaching experiment method, experiment class and control class were selected for implementing two different teaching methods. Difference T test of small samples average was made on the acquired data for revealing the teaching effect difference between two different teaching methods. The result shows that the difference between two teaching methods was significant. The application of "harmonious teaching method" in the sports dance teaching of physical education of general colleges plays a certain positive role in training the comprehensive and harmonious moral, intellectual and physical developments of college students.
文摘With the development of the global economy, learning English has become the need of many Chinese. People have created a lot of English study methods such as Crazy English, Special English, Peipei English, Dapao English, and so on. These methods have made a great impact on our English teaching model. Although there are no enough scientific theories in them, we can find the special ways to learn English well especially for English listening and speaking. If you analyze them carefully, you will be surprised to find that they are very helpful to improve your listening and speaking ability, and overcome the affective shock. Following some of these methods, the learners can get more knowledge, be more interested in English, study harder and obtain the achievements easily, while the teachers can improve their teaching according to them. At last, the author points out that if the teachers can use them in class correctly, the ideal result will come out.
基金commissioned by Bill and Melinda Gates Foundation,Grant/Award Number:OPP1209888.
文摘Background To detect and identify mosquitoes using their characteristic high-pitched sound,we have developed a smartphone application,known as the‘HumBug sensor’,that records the acoustic signature of this sound,along with the time and location.This data is then sent remotely to a server where algorithms identify the species according to their distinctive acoustic signature.Whilst this system works well,a key question that remains is what mechanisms will lead to effective uptake and use of this mosquito survey tool?We addressed this question by working with local communities in rural Tanzania and providing three alternative incentives:money only,short message service(SMS)reminders and money,and SMS reminders only.We also had a control group with no incentive.Methods A multi-site,quantitative empirical study was conducted in four villages in Tanzania from April to August 2021.Consenting participants(n=148)were recruited and placed into one of the three intervention arms:monetary incentives only;SMS reminders with monetary incentives;and SMS reminders only.There was also a control group(no intervention).To test effectiveness of the mechanisms,the number of audio uploads to the server of the four trial groups on their specific dates were compared.Qualitative focus group discussions and feedback surveys were also conducted to explore participants’perspectives on their participation in the study and to capture their experiences of using the HumBug sensor.Results Qualitative data analysis revealed that for many participants(37 out of 81),the main motivation expressed was to learn more about the types of mosquitoes present in their houses.Results from the quantitative empirical study indicate that the participants in the‘control’group switched on their HumBug sensors more over the 14-week period(8 out of 14 weeks)when compared to those belonging to the‘SMS reminders and monetary incentives’trial group.These findings are statistically significant(p<0.05 or p>0.95 under a two-sided z-test),revealing that the provision of monetary incentives and sending SMS reminders did not appear to encourage greater number of audio uploads when compared to the control.Conclusions Knowledge on the presence of harmful mosquitoes was the strongest motive for local communities to collect and upload mosquito sound data via the HumBug sensor in rural Tanzania.This finding suggests that most efforts should be made to improve flow of real-time information back to the communities on types and risks associated with mosquitoes present in their houses.