This paper analyses the principle of microwave humidity testing. According to the problems in the production procedure of ceramic products, a microwave humidity testing system is designed and analyzed for its advantag...This paper analyses the principle of microwave humidity testing. According to the problems in the production procedure of ceramic products, a microwave humidity testing system is designed and analyzed for its advantages. Furthermore, the system has been applied to the production line that produces ceramic products and the testing results are also satisfying.展开更多
The prevention and control of natural gas hydrate(hereinafter,“hydrate”for short)blockage during deepwater gas well production tests is very important in ensuring the test safety.In this paper,the distribution of we...The prevention and control of natural gas hydrate(hereinafter,“hydrate”for short)blockage during deepwater gas well production tests is very important in ensuring the test safety.In this paper,the distribution of wellbore temperature and pressure field under different test conditions was analyzed,and the changes of hydrate deposition and blockage degree in the pipe string in the whole process of test under different test systems were evaluated using the hydrate generationedepositionedecomposition calculation method.On this basis,a deepwater gas well production test method based on hydrate prevention and control was proposed.And the following research results were obtained.First,in the process of deepwater gas well tests,the vaporeliquid phase of annular-mist flow pattern with the greatest risk of hydrate blockage is often formed in the wellbore.Therefore,it is more reasonable to take measures to prevent hydrate blockage in the process of tests than to prevent the formation of hydrate.Second,when the conventional four-point test method is used,it is required to set low gas production measurement points with lower flowing temperature.In the wellbore with high temperature and low temperature,however,hydrate tends to form and deposit easily,and a long period of test will increase the risk of test string blockage.Third,the mixed-sequence test system suitable for deepwater gas well tests can change wellbore temperature by adjusting the sequence of measuring points without changing the production rate and duration,so as to decompose hydrate sediment layers and reduce the maximum blockage degree of test string in the process of tests.Fourth,a three-point or two-point test method is recommended for deepwater gas wells without sand production,stress sensitivity,retrograde condensation and water production.Superior to the conventional four-point test method,three-point and two-point test methods can effectively reduce the risk of hydrate deposition and blockage in the test string,and it can shorten the testing time and reduce the test cost on the premise of ensuring the accuracy of the productivity equation.In conclusion,the research results are of help to the field test construction of deepwater gas wells.展开更多
This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products （non-differentia...This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products （non-differential, with rising temperature）.展开更多
In this paper, the mechanical properties of gas hydrate-bearing sediments (GHBS) were summarized and the instability mechanism of submarine hydrate-bearing slope (SHBS) was analyzed under the background of the test pr...In this paper, the mechanical properties of gas hydrate-bearing sediments (GHBS) were summarized and the instability mechanism of submarine hydrate-bearing slope (SHBS) was analyzed under the background of the test production of gas hydrate in the northern part of the South China Sea. The strength reduction finite element method (SRFEM) was introduced to the stability analysis of submarine slopes for the safety of the test production. Two schemes were designed to determine the physical and mechanical parameters of four target wells. Through the division of the hydrate dissociation region and the design of four working conditions, the range and degree of hydrate dissociation at different stages during the test production were simulated. Based on the software ABAQUS, 37 FEM models of SHBS were set up to analyze and assess the stability of the submarine slopes in the area of the test production. Necessary information such as safety factors, deformation, and displacement were obtained at different stages and under different working conditions. According to the calculation results, the submarine slope area is stable before the test production, and the safety factors almost remains the same during and after the test production. All these indicate that the test production has no obvious influence on the area of the test production and the submarine slopes in the area are stable during and after the test production.展开更多
This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
ISO releases two standards for textiles.Recently,two international standards,ISO 8159:2025,Textiles-Morphology of fibres and yarns-Vocabulary,and ISO 17971:2025,Textiles-Smart textiles-Test method for determining the ...ISO releases two standards for textiles.Recently,two international standards,ISO 8159:2025,Textiles-Morphology of fibres and yarns-Vocabulary,and ISO 17971:2025,Textiles-Smart textiles-Test method for determining the screen-touch properties of fabrics,were officially released.They are of positive significance for eliminating technical ambiguities in exchanges on textile products and filling the gaps in international standards.展开更多
高通量工程试验堆(High Flux Engineering Test Reactor,HFETR)因其高中子通量密度,用于生产各种医用同位素。针对HFETR堆芯结构复杂、非均匀性强、辐照环境变化较大的特点,以“确定论燃料管理-蒙特卡罗粒子输运-产额”耦合计算的策略...高通量工程试验堆(High Flux Engineering Test Reactor,HFETR)因其高中子通量密度,用于生产各种医用同位素。针对HFETR堆芯结构复杂、非均匀性强、辐照环境变化较大的特点,以“确定论燃料管理-蒙特卡罗粒子输运-产额”耦合计算的策略建立了一套适用于不同类型同位素产额精确计算模型及方法。该方法首先通过研究堆专用燃料管理程序完成堆芯装载设计与燃耗计算,获得各时间步的燃料燃耗分布及临界棒位等参数,然后利用自编程序实现自动化全堆精细化建模,并利用蒙特卡罗方法完成输运计算。通过计算获得每一时间步下样品中不同核素与中子的反应率,通过产额求解程序与三维粒子输运蒙卡程序进行耦合,计算出下一个时间步样品内关键核素的含量变化情况,并对换料停堆和从出堆到测量期间的衰变损耗进行计算。该方法综合考虑了HFETR运行期间控制棒变化、燃料燃耗变化及计算燃耗步长的影响,利用HFETR已获得的同位素生产实验结果验证该套计算程序的准确性,对辐照88Sr生产89Sr产额的计算偏差为5.41%,对辐照生产32P产额的计算偏差为4.90%,对辐照生产177Lu产额的计算偏差为5.66%,与实验结果相比同位素产额计算偏差均在6%以内,证明该方法提高了同位素产额计算的精度,能够适用于研究堆生产同位素产额准确评估问题。展开更多
Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of t...Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of the imbalance degree test for projectile body is the test of its product of inertia.A more precise calculation formula of dynamic imbalance degree is also given.The experiment results show that this method can not only reduce the cost of equipment,simplify the test procedures,save human resource,but also has more reliable test precision.展开更多
文摘This paper analyses the principle of microwave humidity testing. According to the problems in the production procedure of ceramic products, a microwave humidity testing system is designed and analyzed for its advantages. Furthermore, the system has been applied to the production line that produces ceramic products and the testing results are also satisfying.
基金supported by the National Program on Key Basic Research Project(973 Program)“Deep-water oil and gas well completion and production tests optimization”(No.:2015CB251205).
文摘The prevention and control of natural gas hydrate(hereinafter,“hydrate”for short)blockage during deepwater gas well production tests is very important in ensuring the test safety.In this paper,the distribution of wellbore temperature and pressure field under different test conditions was analyzed,and the changes of hydrate deposition and blockage degree in the pipe string in the whole process of test under different test systems were evaluated using the hydrate generationedepositionedecomposition calculation method.On this basis,a deepwater gas well production test method based on hydrate prevention and control was proposed.And the following research results were obtained.First,in the process of deepwater gas well tests,the vaporeliquid phase of annular-mist flow pattern with the greatest risk of hydrate blockage is often formed in the wellbore.Therefore,it is more reasonable to take measures to prevent hydrate blockage in the process of tests than to prevent the formation of hydrate.Second,when the conventional four-point test method is used,it is required to set low gas production measurement points with lower flowing temperature.In the wellbore with high temperature and low temperature,however,hydrate tends to form and deposit easily,and a long period of test will increase the risk of test string blockage.Third,the mixed-sequence test system suitable for deepwater gas well tests can change wellbore temperature by adjusting the sequence of measuring points without changing the production rate and duration,so as to decompose hydrate sediment layers and reduce the maximum blockage degree of test string in the process of tests.Fourth,a three-point or two-point test method is recommended for deepwater gas wells without sand production,stress sensitivity,retrograde condensation and water production.Superior to the conventional four-point test method,three-point and two-point test methods can effectively reduce the risk of hydrate deposition and blockage in the test string,and it can shorten the testing time and reduce the test cost on the premise of ensuring the accuracy of the productivity equation.In conclusion,the research results are of help to the field test construction of deepwater gas wells.
文摘This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products （non-differential, with rising temperature）.
基金This work is funded by National Key R&D Project (2017YFC0307605)the China Geological Survey (DD20160217,DD20190218)+1 种基金the National Natural Science Foundation of China (11572165)we would like to extend our sincere appreciation for these.
文摘In this paper, the mechanical properties of gas hydrate-bearing sediments (GHBS) were summarized and the instability mechanism of submarine hydrate-bearing slope (SHBS) was analyzed under the background of the test production of gas hydrate in the northern part of the South China Sea. The strength reduction finite element method (SRFEM) was introduced to the stability analysis of submarine slopes for the safety of the test production. Two schemes were designed to determine the physical and mechanical parameters of four target wells. Through the division of the hydrate dissociation region and the design of four working conditions, the range and degree of hydrate dissociation at different stages during the test production were simulated. Based on the software ABAQUS, 37 FEM models of SHBS were set up to analyze and assess the stability of the submarine slopes in the area of the test production. Necessary information such as safety factors, deformation, and displacement were obtained at different stages and under different working conditions. According to the calculation results, the submarine slope area is stable before the test production, and the safety factors almost remains the same during and after the test production. All these indicate that the test production has no obvious influence on the area of the test production and the submarine slopes in the area are stable during and after the test production.
文摘This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
文摘ISO releases two standards for textiles.Recently,two international standards,ISO 8159:2025,Textiles-Morphology of fibres and yarns-Vocabulary,and ISO 17971:2025,Textiles-Smart textiles-Test method for determining the screen-touch properties of fabrics,were officially released.They are of positive significance for eliminating technical ambiguities in exchanges on textile products and filling the gaps in international standards.
文摘高通量工程试验堆(High Flux Engineering Test Reactor,HFETR)因其高中子通量密度,用于生产各种医用同位素。针对HFETR堆芯结构复杂、非均匀性强、辐照环境变化较大的特点,以“确定论燃料管理-蒙特卡罗粒子输运-产额”耦合计算的策略建立了一套适用于不同类型同位素产额精确计算模型及方法。该方法首先通过研究堆专用燃料管理程序完成堆芯装载设计与燃耗计算,获得各时间步的燃料燃耗分布及临界棒位等参数,然后利用自编程序实现自动化全堆精细化建模,并利用蒙特卡罗方法完成输运计算。通过计算获得每一时间步下样品中不同核素与中子的反应率,通过产额求解程序与三维粒子输运蒙卡程序进行耦合,计算出下一个时间步样品内关键核素的含量变化情况,并对换料停堆和从出堆到测量期间的衰变损耗进行计算。该方法综合考虑了HFETR运行期间控制棒变化、燃料燃耗变化及计算燃耗步长的影响,利用HFETR已获得的同位素生产实验结果验证该套计算程序的准确性,对辐照88Sr生产89Sr产额的计算偏差为5.41%,对辐照生产32P产额的计算偏差为4.90%,对辐照生产177Lu产额的计算偏差为5.66%,与实验结果相比同位素产额计算偏差均在6%以内,证明该方法提高了同位素产额计算的精度,能够适用于研究堆生产同位素产额准确评估问题。
文摘Based on the study of the relation between the dynamic imbalance degree and the product of inertia,a new static test method of the dynamic imbalance degree is presented.It is theoretically proved that the essence of the imbalance degree test for projectile body is the test of its product of inertia.A more precise calculation formula of dynamic imbalance degree is also given.The experiment results show that this method can not only reduce the cost of equipment,simplify the test procedures,save human resource,but also has more reliable test precision.
