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An Analysis of the Party’s Mass Organizing Power Under the New Situation 被引量:1
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作者 Chen Shuangquan Wu Yunzhi 《学术界》 CSSCI 北大核心 2020年第11期226-233,共8页
The mass organizing power is a distinctive feature of the Communist Party of China,an important criterion to test the nature of the proletarian party,and an essential condition to transform the Party’s organizational... The mass organizing power is a distinctive feature of the Communist Party of China,an important criterion to test the nature of the proletarian party,and an essential condition to transform the Party’s organizational advantages into strength superiority.In order to improve the mass organizing power,on the basis of giving full play to the traditional advantages,we’re required to carry out the mass line,and from the perspective of political construction,highlight political functions,strengthening work practices and organization system,taking advantage of technologies,promoting capacity,and intensifying the sense of responsibility,thus to provide a steady stream of power for the great rejuvenation of the Chinese nation. 展开更多
关键词 the new situation mass organizing power path selection
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Mass Stopping Power and Range of Protons in Biological Human Body Tissues (Ovary, Lung and Breast) 被引量:1
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作者 Ahlam S. Almutairi Khalda T. Osman 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2022年第1期48-59,共12页
In this work, the mass stopping power and range of protons in biological human body tissues (ovary, lung and breast) were calculated at the energy ranging from 0.04 MeV to 200 MeV using the MATLAB Program. The data re... In this work, the mass stopping power and range of protons in biological human body tissues (ovary, lung and breast) were calculated at the energy ranging from 0.04 MeV to 200 MeV using the MATLAB Program. The data relating to the densities, average atomic number to mass number  and excitation energy for the present tissues were collected from ICRU Report 46. The mass stopping power was calculated by the Bethe formula. Moreover, the simple integration (continuous slowing down approximation) method was employed for calculating protons range at the tissues. The results of the mass stopping power versus energy and the range versus energy were presented graphically and the empirical formulae for calculating the mass stopping power and the ranges were obtained. The present results for mass stopping powers and ranges were compared with the results obtained by others. Good agreements were found between them, especially at the energy ranging from 3 to 200 MeV. 展开更多
关键词 Human Body Tissues PROTONS RANGE MATLAB mass Stopping power
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RHEOLOGICAL CHARACTERISTICS,POWER CONSUMPTION,MASS AND HEAT,TRANSFER DURING XANTHAN GUM FERMENTATION 被引量:4
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作者 赵学明 胡宗定 +2 位作者 A.W.Nienow C.A.Kent S.Chatwin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1994年第4期15-27,共13页
Xanthan gum fermentation is probably the most complex fermentation process in terms ofrheological property variations and associated mixing,power consumption,mass and heat transferproblems.In order to obtain these dat... Xanthan gum fermentation is probably the most complex fermentation process in terms ofrheological property variations and associated mixing,power consumption,mass and heat transferproblems.In order to obtain these data,fermentations of Xanthomonas campestris were carried outon pilot scale bioreactor with different D/T ratios and different feeding strategies(batch andfed-batch).It was discovered that the rheology of xanthan fermentation broth is of paramountimportance to the above characteristics.The aerated power consumption and power number are both afunction of aeration rate during the initial stage of the fermentation when the viscosity is low andthe Reynolds number high.However when the becames viscous and Reynolds unmber≤10~3,thegas velocity does not show any effect on the power number.The oxygen mass transfer coefficientsand the overall heat transfer coefficients are both dependent on the impeller speed,the apparentviscosity of the broth and the D/T ratio.These data taken from practical 展开更多
关键词 XANTHAN FERMENTATION RHEOLOGY power consumption mass TRANSFER HEAT TRANSFER
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Calculation of Mass Stopping Power and Range of Protons as Well as Important Radiation Quantities in Some Biological Human Bodyparts (Water, Muscle, Skeletal and Bone, Cortical)
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作者 Ahlam S. Almutairi Khalda T. Osman 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2022年第2期99-112,共14页
In this work, the electronic mass stopping power and the range of protons in some biological human body parts (Water, Muscle, Skeletal and Bone, Cortical) were calculated in the energy range of protons 0.04 to 200 MeV... In this work, the electronic mass stopping power and the range of protons in some biological human body parts (Water, Muscle, Skeletal and Bone, Cortical) were calculated in the energy range of protons 0.04 to 200 MeV using the theory of Bethe-Bloch formula as giving in the references. All these calculations were done using Matlab program. The data related to the densities, average atomic number to mass number and excitation energies for the present tissues and substances were collected from ICRU Report 44 (1989). The present results for electronic mass stopping powers and ranges were compared with the data of PSTAR and good agreements were found between them, especially at energies between 1 - 200 MeV for stopping power and 4 - 200 MeV for the range. Also in this study, several important quantities in the field of radiation, such as thickness, linear energy transfer (LET), absorbed dose, equivalent dose, and effective dose of the protons in the given biological human body parts were calculated at protons energy 0.04 - 200 MeV. 展开更多
关键词 Biological Human Bodyparts PROTONS RANGE MatLab PSTAR Electronic mass Stopping power LET Absorbed Dose Effective and Equivalent Dose
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An Anisotropic Geomechanical Model for Jointed Rock Masses at Taishan Nuclear Power Station, Southern China 被引量:1
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作者 ZHENG Wentang CHENG Xiaojiu WANG Huaan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第3期858-870,共13页
An anisotropic geomechanical model for jointed rock mass is presented. Simultaneously with deriving the orthotropic anisotropy elastic parameters along the positive axis, the equivalent compliance matrix for the defle... An anisotropic geomechanical model for jointed rock mass is presented. Simultaneously with deriving the orthotropic anisotropy elastic parameters along the positive axis, the equivalent compliance matrix for the deflection axis orthotropic anisotropy was derived through a three- dimensional coordinate transformation. In addition, Singh's analysis of the stress concentration effects of intermittent joints was adopted, based on two groups of intermittent joints and a set of cross- cutting joints in the jointed rock mass. The stress concentration effects caused by intermittent joints and the coupling effect of cross-cutting joints along the deflection-axis are also considered. The proposed anisotropic mechanics parameters method is applied to determine the deformation parameters of jointed granite at the Taishan Nuclear Power Station. Combined with the deterministic mechanical parameters of rock blocks and joints, the deformation parameters and their variability in jointed rock masses are estimated quantitatively. The computed results show that jointed granite at the Taishan Nuclear Power Station exhibits typical anisotropic mechanical characteristics; the elastic moduli in the two horizontal directions were similar, but the elastic modulus in the vertical direction was much greater. Jointed rock elastic moduli in the two horizontal and vertical directions were respectively about 24% and 37% of the core of rock, showing weakly orthotropic anisotropy; the ratio of elastic moduli in the vertical and horizontal directions was 1.53, clearly indicating the transversely isotropic rock mass mechanical characteristics. The method can be popularized to solve other rock mechanics problems in nuclear power engineering. 展开更多
关键词 Nuclear power Station jointed rock masses anisotropic characteristics constitutive model mechanical parameters
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Preoperative serum vascular endothelial growth factor correlated to three dimensional power Doppler indices in ovarian masses
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作者 Maged R. AbouSeeda Ghada M. Mansour Sahar S. Ez-Elarab 《Open Journal of Obstetrics and Gynecology》 2014年第3期112-119,共8页
Objective: To assess the preoperative serum levels of vascular endothelial growth factor (VEGF) in ovarian masses compared to normal controls and to find a correlation between VEGF and Doppler indices in ovarian masse... Objective: To assess the preoperative serum levels of vascular endothelial growth factor (VEGF) in ovarian masses compared to normal controls and to find a correlation between VEGF and Doppler indices in ovarian masses. Methods: The study was conducted from December 2009 to September 2012 in the oncology and ultrasound units in department of obstetrics and gynecology, Ain Shams University on 150 patients with ovarian masses. During preoperative workup, serum Ca-125 levels and serum VEGF levels were obtained. Ultrasonographic examination included two and three dimensional power Doppler ultrasound (3DPD). Laparotomic approaches were undertaken to obtain the final pathologic results. VEGF was measured in one hundred normal cases as controls. Results: Final ovarian pathology revealed seventy three malignant ovarian masses and seventy seven were benign. Serum Ca-125 levels in malignant cases were higher compared to those in benign cases (p < 0.001). Preoperative serum VEGF revealed higher levels in malignant ovarian masses than benign conditions and normal controls (p < 0.001). Three dimensional power Doppler indices, vascularization index (VI), flow index (FI) and vascularization flow index (VFI), correlated positively with serum VEGF levels. Conclusion: Preoperative serum VEGF revealed higher levels in malignant ovarian masses than benign conditions and normal controls. These levels positively correlated with the Doppler vascular indices of the masses. 展开更多
关键词 OVARIAN Cancer OVARIAN mass Three DIMENSIONAL power DOPPLER VEGF VI FI VFI
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Structural Characteristics and Mechanical Properties of Rock Mass in the Field of Tianwan Nuclear Power Plant, China
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作者 周念清 唐益群 +1 位作者 邓永华 赵在立 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第4期512-517,524,共7页
The structural characteristics and mechanical properties of the rock mass are important parts of the feasibility study on the nuclear power engineering field. In this study, by means of in situ investigation and stati... The structural characteristics and mechanical properties of the rock mass are important parts of the feasibility study on the nuclear power engineering field. In this study, by means of in situ investigation and statistics, the structural plane and joint fissure features of the rock mass were analyzed and discussed at different plots and different depth scopes in the Tianwan Nuclear Power engineering field, the rock mass integrality and its weathered degree were evaluated respectively, and especially, the unfavorable geological phenomena of strongly-weathered cystid existing in the field were studied. According to the results of indoor rock mechanical tests, in combination with drilling, the shallow seismic prospecting, sonic logging and point load tests, the statistical results of physical and mechanical indices of rocks at key plots of the field were analyzed, and the design parameters of the field were calculated. It provided scientific basis for the foundation design of the nuclear power plant. 展开更多
关键词 Tianwan Nuclear power Plant structural PLANE joint FISSURE weathered degree ROCK mass INTEGRALITY MECHANICAL property
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Study of Galaxy Distributions with SDSS DR14 Data and Measurement of Neutrino Masses 被引量:1
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作者 B. Hoeneisen 《International Journal of Astronomy and Astrophysics》 2018年第3期230-257,共28页
We study galaxy distributions with Sloan Digital Sky Survey SDSS DR14 data and with simulations searching for variables that can constrain neutrino masses. To be specific, we consider the scenario of three active neut... We study galaxy distributions with Sloan Digital Sky Survey SDSS DR14 data and with simulations searching for variables that can constrain neutrino masses. To be specific, we consider the scenario of three active neutrino eigenstates with approximately the same mass, so &Sigma;mv=3mv. Fitting the predictions of the ΛCDM model to the Sachs-Wolfe effect, &sigma;8, the galaxy power spectrum Pga1(k) , fluctuations of galaxy counts in spheres of radii ranging from 16/h to 128/h Mpc, Baryon Acoustic Oscillation (BAO) measurements, and h=0.678&plusmn;0.009, in various combinations, with free spectral index n, and free galaxy bias and galaxy bias slope, we obtain consistent measurements of &Sigma;mv. The results depend on h, so we have presented confidence contours in the (&Sigma;mv, h) plane. A global fit with h=0.678&plusmn;0.009 obtains eV, and the amplitude and spectral index of the power spectrum of linear density fluctuations P(k): , and n=1.021&plusmn;0.075. The fit also returns the galaxy bias b including its scale dependence. 展开更多
关键词 NEUTRINO mass GALAXY power SPECTRUM
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一种高效星载功率调节与配电单元设计与实现 被引量:1
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作者 蔡晓东 杜青 +4 位作者 徐泽锋 张俊亭 杨袆 夏宁 王超 《航天器工程》 CSCD 北大核心 2024年第1期42-48,共7页
文章结合深空探测供配电分系统任务特点,提出功率调节、配电、火工控制等多功能模块轻小型一体化设计的必要性。介绍了国外功率调节与配电单元的研究现状、国产功率调节与配电单元研制的意义,功率调节与配电单元组成及功能设计,并通过... 文章结合深空探测供配电分系统任务特点,提出功率调节、配电、火工控制等多功能模块轻小型一体化设计的必要性。介绍了国外功率调节与配电单元的研究现状、国产功率调节与配电单元研制的意义,功率调节与配电单元组成及功能设计,并通过多母线融合设计、多路放电均流设计、单元集成化设计等关键技术,解决了深空探测器高可靠轻小型化功率调节与配电单元设计难题。在轨飞行结果表明:功率调节与配电单元功能正常,工作可靠,性能优良。功率调节与配电单元的国产化设计实现,可为其它航天器的设计提供参考和借鉴。 展开更多
关键词 深空探测 高功率质量比 功率调节与配电单元
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Numerical Studies of Convective Mass Transfer Enhancement in a Membrane Channel by Rectangular Winglets 被引量:1
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作者 闵敬春 张冰强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第10期1061-1071,共11页
Numerical calculations were conducted to simulate the flow and mass transfer in narrow membrane channels with and without flow disturbers. The channel consists of an impermeable solid wall and a membrane surface with ... Numerical calculations were conducted to simulate the flow and mass transfer in narrow membrane channels with and without flow disturbers. The channel consists of an impermeable solid wall and a membrane surface with a spacing of 2.0 mm. The flow disturbers studied include rectangular winglets, which are often used as longitudinal vortex generators to enhance heat transfer in heat exchanger applications, as well as square prism, triangular prism, and circular cylinder, which are used here to mimic the traditional spacer filaments for comparison of their abilities in enhancing the convective mass transfer near the membrane surface to alleviate the concentration polarization. The disturber performance was evaluated in terms of concentration polarization factor versus consumed pumping power, with a larger factor meaning a more serious concentration polarization.Calculations were carried out for Na Cl solution flow with Reynolds numbers ranging from 400 to 1000. The results show that the traditional flow disturbers can considerably reduce the concentration polarization but cause a substantial pressure drop, while the rectangular winglets can effectively reduce the concentration polarization with a much less pressure drop penalty. The rectangular winglets were optimized in geometry under equal pumping power condition. 展开更多
关键词 MEMBRANE CONCENTRATION polarization mass transfer ENHANCEMENT RECTANGULAR WINGLET PUMPING power
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超高层Tuned Mass Damper防震支撑系统技术研究应用 被引量:1
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作者 付正权 张田庆 +3 位作者 陈俊 闵旭 王海江 张茅 《建筑技术开发》 2023年第S01期105-107,共3页
超高层建筑是现代城市建设的重要标志之一,其高度已经超过了传统建筑的极限。然而,随着建筑高度不断增加,地震的破坏力也越来越强,超高层建筑面临着更加严峻的安全挑战。因此,研究超高层建筑防震支撑系统技术非常重要,Tuned Mass Damper... 超高层建筑是现代城市建设的重要标志之一,其高度已经超过了传统建筑的极限。然而,随着建筑高度不断增加,地震的破坏力也越来越强,超高层建筑面临着更加严峻的安全挑战。因此,研究超高层建筑防震支撑系统技术非常重要,Tuned Mass Damper(TMD)是一种被广泛研究和应用的超高层建筑防震支撑系统技术,TMD最初是在20世纪60年代提出的,最早应用于桥梁上,后来,TMD被引入到建筑领域,并得到广泛的应用。通过精确调节质量、阻尼和弹性等参数来削弱地震引起的建筑物减震效应,从而减少了建筑物因地震造成的损害和崩塌的风险. 展开更多
关键词 超高层建筑 破坏力 防震支撑系统 Tuned mass Damper
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Numerical study of hydrodynamic mechanism of dynamic tidal power 被引量:5
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作者 Peng Dai Ji-sheng Zhang +4 位作者 Jin-hai Zheng Kees Hulsbergen Gijs van Banning Jeroen Adema Zi-xuan Tang 《Water Science and Engineering》 EI CAS CSCD 2018年第3期220-228,共9页
Dynamic tidal power is a new way of capturing tidal energy by building a water head using a dike perpendicular to the coast. This study explored the hydrodynamic mechanism of the water head across an intended dynamic ... Dynamic tidal power is a new way of capturing tidal energy by building a water head using a dike perpendicular to the coast. This study explored the hydrodynamic mechanism of the water head across an intended dynamic tidal power dike system using the Delft3 D-FLOW software module. The propagating wave was simulated in a rectangular domain with a horizontal sea bottom at a 30-m depth. A significant water head was created across the dike by blocking the water. The water head increased with increasing dike length and increasing undisturbed tidal current acceleration. The maximum water head for the dike with a length of 50 km, located 900 km from the western boundary, was 2.15 m,which exceeded the undisturbed tidal range. The time series of the water head behaved in a manner identical to the undisturbed tidal current acceleration. The distribution of the water head over the dike assumed an elliptical shape. A parasitic wave was generated at the attachment and scattered outward. The phase lag across the dike did not behave as a linear function of the detour distance. 展开更多
关键词 DYNAMIC TIDAL power Marine RENEWABLE energy Added mass PHASE-SHIFT COASTAL engineering Delft3D
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Current diagnostic approach to patients with adnexal masses: which tools are relevant in routine praxis?
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作者 Milan M. Terzic Jelena Dotlic +6 位作者 Ivana Likic Nebojsa Ladjevic Natasa Brndusic Nebojsa Arsenovic Sanja Maricic Tihomir Mihailovic Sasa Andrijasevic 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第1期55-62,共8页
Objective: The aim of the study was to investigate which anamnestic, laboratory and ultrasound parameters used in routine practice could predict the nature of adnexal mass, thus enabling referral to relevant speciali... Objective: The aim of the study was to investigate which anamnestic, laboratory and ultrasound parameters used in routine practice could predict the nature of adnexal mass, thus enabling referral to relevant specialist. Methods: Study involved the women treated for adnexal tumors throughout a period of 2 years. On admission, detailed anamnestic and laboratory data were obtained, expert ultrasound scan was performed, and power Doppler index (PDI), risk of malignancy index (RMI) and body mass index (BMI) were calculated for all patients. Obtained data were related to histopathological findings, and statistically analyzed. Results: The study included 689 women (112 malignant, 544 benignant, and 33 borderline tumors). Malignant and borderline tumors were more frequent in postmenopausal women (P=0.000). Women who had benignant tumors had the lowest BMI (P=0.000). There were significant (P〈0.05) differences among tumor types regarding erythrocyte sedimentation rate, CA125 and carcinoembryonic antigen (CEA) levels. Among ultrasound findings, larger tumor diameter and ascites were more frequent in malignant tumors (P=0.000). Women with malignant tumors had highest values of RMI and PDI (P=0.000). Conclusions: Anamnestic data, ultrasound parameters and laboratory analyses were all found to be good discriminating factors among malignant, benignant and borderline tumors. 展开更多
关键词 Adnexal mass risk of malignancy index power Doppler index tumor markers body mass index
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Non-Axisymmetric Mass Transfer Phenomenon behind an Orifice in a Curved Swirling Flow
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作者 Tsuyoshi Takano Takayuki Yamagata +1 位作者 Yuki Sato Nobuyuki Fujisawa 《Journal of Flow Control, Measurement & Visualization》 2013年第1期1-5,共5页
The purpose of this paper is to understand the mechanism of non-axisymmetric wall-thinning that caused a pipe break in the pipeline of the Mihama nuclear power plant in 2004. The wall thinning was caused by the flow a... The purpose of this paper is to understand the mechanism of non-axisymmetric wall-thinning that caused a pipe break in the pipeline of the Mihama nuclear power plant in 2004. The wall thinning was caused by the flow accelerated corrosion which affects low carbon steel pipelines. The mass transfer rate measurement of the wall thinning behind an office in a curved swirling flow is carried out in a closed-circuit water tunnel using a benzoic acid dissolution method. The experimental results indicate that the high mass transfer rate is observed on one side of the pipe behind the orifice, which is similar to the observation of the wall-thinning rate in the Mihama case. This result suggests that the influence of the secondary flow in the long elbow combined with the swirling flow can produce the non-axisymmetric mass transfer phenomenon behind the orifice. 展开更多
关键词 Pipe-Wall THINNING Flow ACCELERATED Corrosion ORIFICE mass Transfer NUCLEAR power Plant Benzoic Acid
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固体渗硅制备的Fe-6.5 mass%Si合金的组织演变与磁性能
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作者 刘刚 杨鑫 +2 位作者 刘新丽 唐柏金 刘文龙 《材料热处理学报》 CAS CSCD 北大核心 2021年第7期113-118,共6页
对3mass%冷轧硅钢板材进行固体渗硅和扩散退火处理,采用扫描电镜和X射线衍射仪等研究了其组织、物相和板材厚度方向Si成分的演变,并对其在不同频率下的铁损进行分析。结果表明:经过850℃的固体渗硅后,可在板材上制备出致密的化合物层,... 对3mass%冷轧硅钢板材进行固体渗硅和扩散退火处理,采用扫描电镜和X射线衍射仪等研究了其组织、物相和板材厚度方向Si成分的演变,并对其在不同频率下的铁损进行分析。结果表明:经过850℃的固体渗硅后,可在板材上制备出致密的化合物层,化合物层由表面的FeSi相层和邻近的Fe3Si相层构成;随着渗硅时间的增加,FeSi相层厚度不变,Fe3Si相层厚度增加;当板材心部完全形成Fe3Si相后,FeSi相层厚度开始增大。在扩散退火过程中,板材表面化合物层中Si向心部扩散,最终形成Si沿厚度方向均匀分布的、由单一α-Fe相构成的Fe-6.5 mass%Si合金。在较低的频率(1000 Hz)下,Fe-6.5 mass%Si合金的铁损高于3 mass%硅钢;在中等频率下(1000-20000 Hz),二者铁损接近;在较高的频率下(>20000 Hz),Fe-6.5 mass%Si合金的铁损小于3 mass%硅钢,频率越高差异越大。 展开更多
关键词 Fe-6.5 mass%Si合金 固体渗硅 扩散 组织 铁损
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Mass transfer coefficients in metallurgical reactors 被引量:1
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作者 Ying QuMetallurgical Engineering School, University of Science and Technology Beijing, Beijing 100083, China 《Journal of University of Science and Technology Beijing》 CSCD 2003年第2期1-9,共9页
An overview on the application and achievements of physico-mathematicalmodeling of metallurgical processes in China is briefly declared. The important role of coefficientsin model formulation is shown from our experie... An overview on the application and achievements of physico-mathematicalmodeling of metallurgical processes in China is briefly declared. The important role of coefficientsin model formulation is shown from our experience. The mass transfer coefficients of the slag-metalreactions and the gas-metal reactions are discussed referring to the flow conditions near theinterface. The influence of the surface-active species on the mass transfer and the interfacialreaction is also discussed briefly. 展开更多
关键词 mass transfer MODELING PYROMETALLURGY reaction engineering interfacial flow stirring power
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流动空间权力关系的建构与现实转换——对卡斯特传播权力理论的历史唯物主义考察
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作者 黄其洪 任艳华 《西南大学学报(社会科学版)》 CSSCI 北大核心 2024年第2期95-105,共11页
随着全球信息技术的革新,卡斯特将具有虚拟性、开放性、全球化等特征的流动空间设定为网络社会特有的空间形式,并以此为前提对流动空间中权力关系的建构及其现实转换进行了系统性的考察。在现实的推动下,卡斯特认为流动空间中的权力关... 随着全球信息技术的革新,卡斯特将具有虚拟性、开放性、全球化等特征的流动空间设定为网络社会特有的空间形式,并以此为前提对流动空间中权力关系的建构及其现实转换进行了系统性的考察。在现实的推动下,卡斯特认为流动空间中的权力关系存在着权力主体从精英转向大众、权力载体从网络公共空间走向城市公共空间、权力变革目标从政治改革通向社会变革的可能性。这种现实转换发生的条件首先在于作为流动空间权力关系新载体的大众自传播的兴起,另一个更为基础的条件则是处于被权力压制的大众通过对恐惧情绪的克服推动了网络社会运动向前发展,并且具有重建公共空间的潜力。卡斯特以流动空间中的权力关系为研究对象所建构起来的具有历史唯物主义特质的理论构想,为数字时代的政治改革、社会变革、人的自由解放以及国际新秩序的构建等重大现实议题注入了思想活力。 展开更多
关键词 流动空间 权力关系 大众自传播 数字时代 网络社会运动 历史唯物主义
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Comparison and Evaluation of Power Factor Correction Topologies for Industrial Applications
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作者 John Karatzaferis Nick Papanikolaou +2 位作者 Emmanuel Tatakis Michael Loupis John Spanoudakis 《Energy and Power Engineering》 2013年第6期401-410,共10页
Power factor correction is a major issue for all industries, since a typical industrial load is causing current delays, as well as higher order current harmonics. Power factor correction is often mandatory from the po... Power factor correction is a major issue for all industries, since a typical industrial load is causing current delays, as well as higher order current harmonics. Power factor correction is often mandatory from the power companies, usually by charging the reactive power that the company consumes. Many solutions for power factor correction have been presented in the bibliography;in this paper, the most significant power factor correction topologies will be reviewed and simulated with SABER RD software. Finally, a prototype design will be presented, based on a mass/cost analysis of the selected topologies and with an aim to manufacture 10 kW modules. The main outcome of this work is the feasibility for an SME to manufacture a competitive modular power factor correction product for industrial applications. 展开更多
关键词 power FACTOR CORRECTION Industrial Load CONVERTER Thermal Design mass/Volume Analysis
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水田动力底盘逆向建模与质心验证——基于Geomagic Design X
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作者 何剑飞 曾志浩 +5 位作者 郭梓游 李贵蓉 钟文能 钟顺 王在满 李庆 《农机化研究》 北大核心 2024年第10期248-253,共6页
针对目前农业机械仿真和优化模型精度不高的问题,提出了一种构建精确模型的逆向建模方法。应用光学扫描仪采集点云数据,基于Geomagic Design X处理点云数据并重构零部件模型,在SolidWorks中完成水田动力底盘的装配。以VP6D-CQ型水田动... 针对目前农业机械仿真和优化模型精度不高的问题,提出了一种构建精确模型的逆向建模方法。应用光学扫描仪采集点云数据,基于Geomagic Design X处理点云数据并重构零部件模型,在SolidWorks中完成水田动力底盘的装配。以VP6D-CQ型水田动力底盘为例,将测得的实际质心位置与所建的模型质心位置进行比较,并对提出的逆向建模方法进行了试验验证以及误差分析。结果表明:总质量、x坐标、y坐标、z坐标的误差值分别为4.55%、3.62%、2.23%、4.81%,误差值均在5%内。此方法可构建准确的三维模型,为后续仿真优化数据精确性奠定了基础,与传统的研发相比较,可缩短农业机械研发周期、降低设计成本。 展开更多
关键词 水田 动力底盘 逆向建模 质心验证 Geomagic Design X 数字样机
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质子交换膜燃料电池随行波流场设计与传质特性
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作者 朱鑫宁 王茜 +3 位作者 刘荣康 朱思明 张剑波 周伟 《汽车安全与节能学报》 CAS CSCD 北大核心 2024年第3期351-359,共9页
为了提高质子交换膜燃料电池(PEMFC)的膜电极的传质性能与电池的功率密度,设计了一种以圆弧凹面作为强化传质结构的随行波流场板。结合铣削工艺,实现了随行波流场结构的制造。采用计算流体动力学软件,建立包括随行波流场与膜电极在内的... 为了提高质子交换膜燃料电池(PEMFC)的膜电极的传质性能与电池的功率密度,设计了一种以圆弧凹面作为强化传质结构的随行波流场板。结合铣削工艺,实现了随行波流场结构的制造。采用计算流体动力学软件,建立包括随行波流场与膜电极在内的燃料电池三维模型。实验验证了该模型的准确性。探索了强化传质结构对电池内部速度场、浓度场及电场的分布规律,分析了电池性能的提升效果。结果表明:与流道深宽0.6 mm×0.8 mm的常规流场相比,该文的随行波流场的平均流速提升了27.7%,压损降低了19.2%,双极板—气体扩散层界面的氧气含量提升了1.44%,出口的排水速率增大16.7%,功率密度提升了8.6%。 展开更多
关键词 质子交换膜燃料电池(PEMFC) 随行波流场 传质性能 功率密度
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