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There are currently few methods available to measure the conductance of water vapor through an orifice. The feasibility of the pressure rising method to measure the conductance of water vapor is analyzed by combining theory with experiment, indicating that the measurement error of this method increases with the decrease of intake volume, which is due to the strong adsorption characteristic of water vapor. To accurately obtain the relationship between the conductance of water vapor and the inlet pressure, a new method called the time-ratio method is proposed. This method calculates conductance by measuring the time of pressure change, reducing the effect of water vapor adsorption on the measurement effectively. Based on this method, a device is developed to provide a flow rate in the range of 3. 7×10-9 ~1. 5×10-5 Pa·m³· s-1. The measurement and theoretical values of conductance have good consistency, and the relative standard uncertainty of this time‑ratio method is 3. 3%. [ABSTRACT FROM AUTHOR]

Based on the particle-in-cell (PIC) method and the Monte Carlo method, the software of VSim was used to analyze the Penning discharge of the miniature sputter ion pump (SIP). A two-dimensional simulation model was established, and the parameters such as the incident energy, the incident angle, and the incident position on the cathode plate were obtained. The non- vertical sputtering yield theory was combined with the simulation results, and the distribution law of the sputtering yield on the cathode plate was obtained. According to the ion incident parameters and the sputtering yield, the pumping speed of the miniature SIP for nitrogen was calculated. The calculated values are in good agreement with the experimental results, and the method can accurately give the pressure corresponding to the threshold value of the pumping speed. In the simulation results, the length of the anode barrel can effectively reduce the pressure corresponding to the threshold value of the pumping speed. Meanwhile, it was also proved by experiments. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Chemistry is the property of Chinese Journal of Applied Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The pumping speed measuring apparatus, which employs the flowmeter method, was introduced. The pressure was measured by using a spinning rotor gauge(SRG) under 1×10-4 to 1×10-2Pa, and the ionization vacuum gauge was used when the pressure was lower than 10-4Pa. A method of measuring the pumping speed and the outgassing rate of the extractor gauge was given. The pumping speed and the outgassing rate of the extractor gauge were measured under the pressure of 10-6 to 10-4Pa. The flowmeter method was used to measure the pumping speed of the miniature sputter ion pump(SIP)in nitrogen and helium. The discharge state of the miniature SIP under different pressures was analyzed using COMSOL, and the experimental results were in good agreement with the theoretical analysis. The combined standard uncertainty of the flowmeter method was less than 4.4%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Frontiers of Computer Science & Technology is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Big Data is the property of Journal of Agricultural Big Data Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The throat area of the nozzle is important for the performance of the steam ejector， a variable area nozzle structure which is capable to adjust the nozzle throat area by adjusting the position of spindle is proposed and the numerical analysis toward the influence of the spindle positions on the performance of the steam ejector is also discussed. The velocity flow field， axial pressure distribution and near-wall flow field of the steam ejector under different spindle positions were compared. The results showed that under the same working condition， the spindle position can significantly affect the performance of the steam ejector. With the decreasing of nozzle throat area， the shock wave position in the jet pump was shifted to the inlet direction， and the intensity was continuously weakened. The phenomenon of boundary layer separation is weakened first and then enhanced. When the nozzle spindle position is around 15 mm， the performance of jet pump reached the best value. [ABSTRACT FROM AUTHOR]

The back pressure resistance of the steam ejector was evaluated by the kinetic energy e of the unit volume of the steam ejector’s throat outlet section. The influence of geometric parameters of the ejector including throat diameter d,mixing chamber angle θ and nozzle exit position s on the steam ejector’s back pressure resistance and the relationship between e and the steam ejetor’s back pressure resistance were studied by using the computational fluid dynamics( CFD) method. The results showed that as d or θ decreases,or s increases,e and the back pressure resistance of steam ejector increase. When d,θ and s change,e can be used as a standard for evaluating the capability to resist the back pressure of steam ejectors. [ABSTRACT FROM AUTHOR]

In order to obtain a prediction and analysis method for shale production performance, the average water saturation equation and gas-water two phase material balance equation are obtained by integrating the water and gas phase continuity equations. Combined with the finite difference method, the calculation steps are given, and the effect of the dimensionless conductivity, fracture half-length, Langmuir volume and Langmuir constant on daily production of vertical fracture wells are analyzed. Compared with the numerical simulation results, the correctness of the method is verified. The results show that the dimensionless conductivity and fracture half-length only affect the maximum production, while the Langmuir volume and Langmuir constant affect both the maximum production and the start time of decline. The results provide a new way to establish the material balance equation of shale gas, which also can be used for the production potential and the evaluation of fracturing construction scheme. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Modern Medicine & Health is the property of Journal of Modern Medicine & Health and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the wind-resistance design of a bridge across the Yangtze River, using 1颐100 of the full scale aero-elastic model wind tunnel tests, we conducted a comparative study of buffeting response of the cable-stayed bridge in completion condition and longest cantilever condition under cross wind and skew wind, and calculated the buffeting forces of girders combined with finite element models. The results indicates that, the skew wind could enlarge the lateral displacement of the end of the longest cantilever structure comparing the one under cross wind, which needed to pay attention during erection. The buffeting response of the bridge in service condition under cross wind were larger than the ones under skew wind, which implied that there was no need to consider the effect of skew wind on 500 m-span cable-stayed bridge. The buffeting force also provided the parameters of the selection of the lateral bearing. The research also provides some reference for the wind - resistance design of regular cable-stayed bridges. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To determine the operating characteristics of ejector, evaluate the numerical model calculation accuracy and improve the ejector pump theory, an experimental system of small steam jet refrigeration was set up. The relationships between the steam jet pump performance and working steam pressure, suction pressure, the back pressure of the ejector were studied by using experimental method. The experimental results show that the secondary fluid flow rate and ejector coefficient (entrainment ratio, ER) increase firstly to the maximum and then decrease gradually with increasing the working steam pressure. With increasing suction pressure, the secondary fluid flow rate and the ER increase. The ER keeps a constant value in a certain range of back pressure and declines sharply when back pressure is bigger than the critical back pressure. It is important to understand the pumping characteristic of steam jet pump deeply based on the experimental research, and the experimental data can be used to optimize steam jet pump's structure. [ABSTRACT FROM AUTHOR]

A theoretical model for describing the pumping performance of compound molecular pump's drag stage was established. According to the theoretical model， the relationship between the depth of drag stage’s spiral groove and compression ratio was studied under different spiral angles， rotor-stator clearances， rotor speeds and gas flows. The results showed that compression ratio firstly increases and then decreases with the decrease of spiral groove’s depth. There exists the optimal groove depth， which result in the maximum compression ratio of drag stage. The spiral angles have little effect on the optimal groove depth which decreases with the decrease of the rotor-stator clearances， and increases with the increase of the rotor speed. The optimal groove depth is smaller when the gas flow is viscous. [ABSTRACT FROM AUTHOR]

The circulating cooling water pump in a nuclear power plant operates in a high temperature environment， and the pump bearing receives a large amount of heat load， so the work reliability is of great importance. To reduce the bearing's working temperature and ensure its safe operation， a cooling device should be installed in the pump system. The structure of the bearing's axial flow cooling fan in the pump was proposed， and the optimum design method of the bearing's axial flow cooling fan in the pump was established. For the fan blades， the optimized calculation using BFGS algorithm was proceeded. A simulation verification of the system was proposed by using FLUENT， whose results showed that the design method is suitable for the bearing's axial flow cooling fan design in circulating cooling water pumps in a nuclear power plant. [ABSTRACT FROM AUTHOR]

Objective To explore the effect of ibandronate on prognosis of osteoporotic intertrochanteric fractures in the elderly.Methods A total of 135 elderly patients who were operated for the intertrochanteric fracture in the department of orthopedics of our hospital from September 2011 to June 2013 were selected. One hundred and twenty patients whose T score of the femoral neck lower than- 2. 5 were selected. These patients were randomly divided to 4 groups: including Group A( control group),Group B( drug applied from one week after surgery),Group C( drug applied from one month after surgery),and Group D( drug applied from three months after surgery). All patients received ibandronate 2mg intravenous injection for 2 consecutive days,once every 3months,and continued for one year. Fracture healing,complications,and changes in bone mineral density were followed up. The data were expressed as M± SD( x± s). The comparison of enumeration data used repeated measurement variance analysis. P <0. 05 was considered statistically significant. Results The mean time of fracture healing was not statistically significant among the4 groups. A total of 18 patients were loss of follow-up due to failure of fixation or death. The difference of the complication was not different among the 4 groups. Harris hip score and complication of all patients among the 4 groups were not statistically different.Bone mineral density in group B,C,and D increased significantly compared with that before the operation,but bone mineral density in group A decreased. The difference was statistically significant. Conclusion The research indicates that administration of ibandronate at different time increases bone mineral density in elderly patients with intertrochanteric fractures,with no unfavorable effect to the prognosis. [ABSTRACT FROM AUTHOR]

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

目的 观察气管镜下常规介入并放置 Dumon 支架治疗肺癌袖状切除术后吻合口狭窄的效果。方法 回顾性分析1例常规介入并放置Dumon支架治疗肺癌袖状切除术后吻合口狭窄患者的临床资料,并复习相关文献。结果 患者男,57岁,1 a前因右肺上叶鳞癌行右肺上叶袖状切除术,术后3个月因咳嗽及活动后喘憋入院,行胸部CT检查示右中叶及右下叶肺不张,行电子气管镜检查诊断为右肺上叶袖状切除术后吻合口狭窄并闭锁,给予气管镜下电切、二氧化碳冷冻、球囊扩张等介入治疗并放置Dumon支架1枚,术后临床症状明显缓解,复查胸部CT示右肺复张。结论 气管镜下常规介入并放置Dumon支架治疗肺叶袖状切除术后吻合口狭窄临床效果较好。 [ABSTRACT FROM AUTHOR]

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)