Considering the influence of quadratic gradient term and medium deformation on the seepage equation, a well testing interpretation model for low permeability and deformation dual medium reservoirs was derived and esta...Considering the influence of quadratic gradient term and medium deformation on the seepage equation, a well testing interpretation model for low permeability and deformation dual medium reservoirs was derived and established. The difference method was used to solve the problem, and pressure and pressure derivative double logarithmic curves were drawn to analyze the seepage law. The research results indicate that the influence of starting pressure gradient and medium deformation on the pressure characteristic curve is mainly manifested in the middle and late stages. The larger the value, the more obvious the upward warping of the pressure and pressure derivative curve;the parameter characterizing the dual medium is the crossflow coefficient. The channeling coefficient determines the time and location of the appearance of the “concave”. The smaller the value, the later the appearance of the “concave”, and the more to the right of the “concave”.展开更多
The ultrasonic attenuation coefficient is one of the most important acoustic parameters to character the performance of a thin layer media, but it can not be measured due to mutual superposition of multiple reflected ...The ultrasonic attenuation coefficient is one of the most important acoustic parameters to character the performance of a thin layer media, but it can not be measured due to mutual superposition of multiple reflected waves at the same interface in ultrasonic testing. Ultrasonic pulse echo and lamb wave to evaluate the thin layer media can not obtain attenuation coefficient at present. In this paper, analytical method was used to study the acoustics characteristic of thin layer media with the ultrasonic echo testing. Meanwhile, the process of ultrasonic attenuation measurement was presented. Simulation and experimental investigation is focused on a thin layer of rubber. Attenuation coefficient was introduced and evaluation mathematics model was established by the two echoes cross-correlation with and without the thin layer media based on the time delay spectrum. It involved the parameters related to the acoustic properties of the thin layer media. Through calculating the sound velocity and acoustic impedance with the evaluation model, it can deduce the relation between the attenuation coefficient and the frequency. Through analyzing the simulation results, it indicated that the attenuation coefficients were invariable with the varying of the frequency. However, the attenuation coefficients increased with the frequency increasing by ultrasonic testing the thin layer of rubber. The reason was that the attenuation factor was not taken into account during the simulation. This method overcomes shortcomings that the traditional ultrasonic testing can not evaluate the thin layer media whose thickness is less than motivation wavelength. It is a new solution to study the attenuation characteristic and on-line nondestructive evaluation in the thin layer media.展开更多
in order to elucidate the relationship between secretory otitis media (SOM) and allergy,the tympanogram and allergic skin test with house dust, mite, and Japanese cedar pollen allergen were made in 2702 pupils in Shir...in order to elucidate the relationship between secretory otitis media (SOM) and allergy,the tympanogram and allergic skin test with house dust, mite, and Japanese cedar pollen allergen were made in 2702 pupils in Shiraoi, Hokkaido, Japan. The correlation between the tympanogram type and the results of allergic skin was analyzed. This study suggests that there is no positive relationship between SOM and allergy.展开更多
为保证原料乳质量,丰富检测原料乳中大肠菌群涉及到的培养基的验收质控菌株,采用GB 4789.28—2013《食品安全国家标准 食品微生物学检验 培养基和试剂的质量要求》中规定的验收方法,分别选取3个品牌的结晶紫中性红胆盐琼脂(violet red b...为保证原料乳质量,丰富检测原料乳中大肠菌群涉及到的培养基的验收质控菌株,采用GB 4789.28—2013《食品安全国家标准 食品微生物学检验 培养基和试剂的质量要求》中规定的验收方法,分别选取3个品牌的结晶紫中性红胆盐琼脂(violet red bile agar,VRBA)、结晶紫中性红胆盐-4-甲基伞形酮-β-D-葡萄糖苷琼脂(violet red bile agar with MUG,VRBA-MUG)、月桂基硫酸盐胰蛋白胨肉汤(lauryl tryptose broth,LST)和煌绿乳糖胆盐肉汤(brilliant green lactose bile broth,BGLB),对其进行外观、pH值、水分含量等物理指标以及生长率、选择性等微生物指标实验评价。同时以弗式柠檬酸杆菌ATCC 43864为参照,选取7株弗式柠檬酸杆菌对3个品牌的VRBA、VRBA-MUG、LST和BGLB进行验收实验评价。结果表明:3个品牌的不同培养基干粉颜色均正常,水分含量均控制在5%~6%,pH值均符合国家标准;7株弗氏柠檬酸杆菌在3个品牌VRBA、VRBA-MUG上的生长率均大于0.7;仅CMCC 48098和CICC 22910在3个品牌的LST、BGLB中浊度达到2,且导管内产生气体,与ATCC 43864结果相同。综上,3个品牌的VRBA、VRBA-MUG、LST和BGLB全部符合GB 4789.28—2013,推荐CMCC 48098和CICC22910用作验收4个培养基质控菌株的补充菌株。展开更多
文摘Considering the influence of quadratic gradient term and medium deformation on the seepage equation, a well testing interpretation model for low permeability and deformation dual medium reservoirs was derived and established. The difference method was used to solve the problem, and pressure and pressure derivative double logarithmic curves were drawn to analyze the seepage law. The research results indicate that the influence of starting pressure gradient and medium deformation on the pressure characteristic curve is mainly manifested in the middle and late stages. The larger the value, the more obvious the upward warping of the pressure and pressure derivative curve;the parameter characterizing the dual medium is the crossflow coefficient. The channeling coefficient determines the time and location of the appearance of the “concave”. The smaller the value, the later the appearance of the “concave”, and the more to the right of the “concave”.
基金supported by National Natural Science Foundation of China (Grant No. 50802009)Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20070151024)
文摘The ultrasonic attenuation coefficient is one of the most important acoustic parameters to character the performance of a thin layer media, but it can not be measured due to mutual superposition of multiple reflected waves at the same interface in ultrasonic testing. Ultrasonic pulse echo and lamb wave to evaluate the thin layer media can not obtain attenuation coefficient at present. In this paper, analytical method was used to study the acoustics characteristic of thin layer media with the ultrasonic echo testing. Meanwhile, the process of ultrasonic attenuation measurement was presented. Simulation and experimental investigation is focused on a thin layer of rubber. Attenuation coefficient was introduced and evaluation mathematics model was established by the two echoes cross-correlation with and without the thin layer media based on the time delay spectrum. It involved the parameters related to the acoustic properties of the thin layer media. Through calculating the sound velocity and acoustic impedance with the evaluation model, it can deduce the relation between the attenuation coefficient and the frequency. Through analyzing the simulation results, it indicated that the attenuation coefficients were invariable with the varying of the frequency. However, the attenuation coefficients increased with the frequency increasing by ultrasonic testing the thin layer of rubber. The reason was that the attenuation factor was not taken into account during the simulation. This method overcomes shortcomings that the traditional ultrasonic testing can not evaluate the thin layer media whose thickness is less than motivation wavelength. It is a new solution to study the attenuation characteristic and on-line nondestructive evaluation in the thin layer media.
文摘in order to elucidate the relationship between secretory otitis media (SOM) and allergy,the tympanogram and allergic skin test with house dust, mite, and Japanese cedar pollen allergen were made in 2702 pupils in Shiraoi, Hokkaido, Japan. The correlation between the tympanogram type and the results of allergic skin was analyzed. This study suggests that there is no positive relationship between SOM and allergy.
文摘为保证原料乳质量,丰富检测原料乳中大肠菌群涉及到的培养基的验收质控菌株,采用GB 4789.28—2013《食品安全国家标准 食品微生物学检验 培养基和试剂的质量要求》中规定的验收方法,分别选取3个品牌的结晶紫中性红胆盐琼脂(violet red bile agar,VRBA)、结晶紫中性红胆盐-4-甲基伞形酮-β-D-葡萄糖苷琼脂(violet red bile agar with MUG,VRBA-MUG)、月桂基硫酸盐胰蛋白胨肉汤(lauryl tryptose broth,LST)和煌绿乳糖胆盐肉汤(brilliant green lactose bile broth,BGLB),对其进行外观、pH值、水分含量等物理指标以及生长率、选择性等微生物指标实验评价。同时以弗式柠檬酸杆菌ATCC 43864为参照,选取7株弗式柠檬酸杆菌对3个品牌的VRBA、VRBA-MUG、LST和BGLB进行验收实验评价。结果表明:3个品牌的不同培养基干粉颜色均正常,水分含量均控制在5%~6%,pH值均符合国家标准;7株弗氏柠檬酸杆菌在3个品牌VRBA、VRBA-MUG上的生长率均大于0.7;仅CMCC 48098和CICC 22910在3个品牌的LST、BGLB中浊度达到2,且导管内产生气体,与ATCC 43864结果相同。综上,3个品牌的VRBA、VRBA-MUG、LST和BGLB全部符合GB 4789.28—2013,推荐CMCC 48098和CICC22910用作验收4个培养基质控菌株的补充菌株。
