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Density of Liquid Ni-Mo Alloys Measured by a Modified Sessile Drop Method 被引量:4
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作者 LiangFANG ZushuLI +1 位作者 ZaiNanTAO FengXIAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第3期287-292,共6页
The density of liquid binary Ni-Mo alloys with molybdenum concentration from 0 to 20% (mass fraction) wasmeasured by a modified sessile drop method. It has been found that the density of the liquid Ni-Mo alloys decrea... The density of liquid binary Ni-Mo alloys with molybdenum concentration from 0 to 20% (mass fraction) wasmeasured by a modified sessile drop method. It has been found that the density of the liquid Ni-Mo alloys decreaseswith increasing temperature, but increases with the increase of molybdenum concentration in the alloys. The molarvolume of liquid Ni-Mo binary alloys increases with the increase of temperature and molybdenum concentration. Thepartial molar volume of molybdenum in Ni-Mo binary alloy has been approximately calculated as [13.18-2.65×10^(-3)T+(-47.94+3.10×10^(-2)T)×10^(-2)X_(Mo)]×10^(-6)m^3·mol^(-1). The molar volume of Ni-Mo alloy determined inthe present work shows a negative deviation from the ideal linear mixing molar volume. 展开更多
关键词 Ni-Mo alloy Densityv Modified sessile drop method Molar volume MOLYBDENUM
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Density Measurement of Liquid Ni-Ta Alloys by a Modified Sessile Drop Method 被引量:1
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作者 方亮 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第2期67-70,共4页
The density of liquid Ni-Ta alloys was measured by using a modified sessile drop method. It is found that the density of the liquid Ni-Ta alloys decreases with the increasing temperature, but increases with the increa... The density of liquid Ni-Ta alloys was measured by using a modified sessile drop method. It is found that the density of the liquid Ni-Ta alloys decreases with the increasing temperature, but increases with the increase of tantalum concentration in the alloys. The molar volume of liquid Ni-Ta binary alloys increases with the increase of temperature and tantalum concentration. 展开更多
关键词 Ni-Ta alloy DENSITY modified sessile drop method molar volume tantalum concentration
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Surface tension of molten tin investigated with sessile drop method 被引量:1
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作者 李晶 袁章福 +1 位作者 范建峰 柯家骏 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第5期1166-1171,共6页
The surface tension of molten tin was determined by a set of self-developed digital equipment with sessile drop method at oxygen partial pressure of 1.0×10 -6MPa under different temperatures, and the dependence... The surface tension of molten tin was determined by a set of self-developed digital equipment with sessile drop method at oxygen partial pressure of 1.0×10 -6MPa under different temperatures, and the dependence of surface tension of molten tin on temperature was also discussed. The emphasis was placed on the comparison of surface tension of the same molten tin sample measured by using different equipments with sessile drop method. Results of the comparison indicate that the measurement results with sessile drop method under the approximate experimental conditions are coincident, and the self-developed digital equipment for surface tension measurement has higher stability and accuracy. The relationships of surface tension of molten tin and its temperature coefficient with temperature and oxygen partial pressure were also elucidated from the thermodynamic equilibrium analysis. 展开更多
关键词 熔化工艺 界面结构 金属结构 金属物理学
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Density of liquid NiCoAlCr quartemary alloys measured by modified sessile drop method
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作者 方亮 张淑芳 +5 位作者 肖锋 杨凌川 董建新 曹春兰 陶再南 K.MUKAI 《中国有色金属学会会刊:英文版》 CSCD 2006年第A03期1962-1966,共5页
The densities of liquid NiCoAlCr quaternary alloys with a fixed molar ratio of Ni to Co to Al (x(Ni):x(Co):x(Al)≈73:12.15) which is close to the average value of the commercial Ni-based superalloys TMS75, INCO713, CM... The densities of liquid NiCoAlCr quaternary alloys with a fixed molar ratio of Ni to Co to Al (x(Ni):x(Co):x(Al)≈73:12.15) which is close to the average value of the commercial Ni-based superalloys TMS75, INCO713, CM247LC and CMSX-4, and the mass fraction of chromium changes from 0 to 9% were measured by a modified sessile drop method. It is found that with increasing temperature and chromium concentration in the alloys, the densities of the liquid NiCoAlCr quaternary alloys decrease, whereas the molar volume of the liquid NiCoAlCr quaternary alloys increases. And the liquid densities of NiCoAlCr quaternary alloys calculated from the partial molar volumes of nickel, cobalt, aluminum and chromium in the corresponding Ni-bases binary alloys are in good agreement with the experimental ones, i.e. within the error tolerance range the densities of the liquid Ni-based multi-component alloys can be predicted from the partial volumes of elements in Ni-based binary alloys in liquid state. The molar volume of liquid NiCoAlCr binary alloy shows a negative deviation from the ideal linear mixing and the deviation changes small with the increase of chromium concentration at the same temperature. 展开更多
关键词 钴合金 有色金属 液相 抗热性
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Measurement of contact angle between stainless steel surface and carbon dioxide by pendant drop method
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作者 PEI NianQiang GUO KaiHua +1 位作者 LIU Jie LI TingXun 《Chinese Science Bulletin》 SCIE EI CAS 2008年第16期2560-2564,共5页
To measure contact angle between CO2 and solid surface, in this study a visual high-pressure vessel has been developed, with a corresponding well-controlled constant temperature system. Pendant drop method is applied ... To measure contact angle between CO2 and solid surface, in this study a visual high-pressure vessel has been developed, with a corresponding well-controlled constant temperature system. Pendant drop method is applied to the investigation of the contact angles of CO2 on a stainless steel surface in its own vapor. The image of the pendant drop is recorded by a camera, and a B-Snake method is used to analyze the contour and the contact angle of the droplet. The experimental results have provided a set of well tested data, which show that CO2 has good infiltration into stainless steel surface and the de- veloped method can be used as a standard testing one for measuring the contact angle between high-pressure liquid and solid surface. 展开更多
关键词 二氧化碳 固体表面 温度系统 悬膜下垂
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Morphology observation of dipalmitoyl phosphatidyl choline (DPPC) monolayer on water surface by dropping method
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作者 Daisuke Yoshida Takashi Yokoyama +9 位作者 Takatsugu Shimoaki Takashi Tomita Tadayoshi Yoshida Yasushi Yamamoto Keijiro Taga Ayumi Sumino Takehisa Dewa Mamoru Nango Masato Yamamoto Zameer Sheravani 《Journal of Biophysical Chemistry》 2013年第4期115-121,共7页
Preparation of DPPC lipid monolayer in water trough has been done by dropping method and compared with compression method. Monolayer was studied by surface pressure isotherm, fluorescence microscopy, Brewster angle mi... Preparation of DPPC lipid monolayer in water trough has been done by dropping method and compared with compression method. Monolayer was studied by surface pressure isotherm, fluorescence microscopy, Brewster angle microscopy, and infrared external reflection spectroscopy. Results of these measurements showed that dropping method gave better results compared to compression method. In dropping method, transition from liquid expanded state to liquid condensed is gradual compared to sharp one in compressed method. During monolayer formation, adjustment and interaction between hydrophilic part of lipid and water and among hydrophobic part of lipid molecule are slow, stable, and more natural as worked out from surface area versus pressure isotherm. At a given molecular area, surface pressure is less compared to compression method thus monolayer is in more fluidic state in dropping method than compression method. The observation was supported by all techniques described above. 展开更多
关键词 DPPC MONOLAYER dropPING method Surface Tension Fluorescence MICROSCOPY BREWSTER Angle MICROSCOPY
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MorphologicaObservation of Specific Condensation Effect of Cholesterol on Dipalmitoyl Phosphatidyl Choline (DPPC) Monolayer by Dropping Method
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作者 Takashi Yokoyama Daisuke Yoshida +8 位作者 Hiroya Mori Masaya Okabe Zameer Shervani Keijiro Taga Yasushi Yamamoto Ayumi Sumino Takehisa Dewa Mamoru Nango Masato Yamamoto 《Journal of Biophysical Chemistry》 2016年第4期98-109,共12页
Morphology of dipalmitoyl phosphatidyl choline (DPPC)-cholesterol (Chol) mixed monolayer formed on water surface by dropping method was investigated using surface tension measurement (STm), Brewster angle microscopy (... Morphology of dipalmitoyl phosphatidyl choline (DPPC)-cholesterol (Chol) mixed monolayer formed on water surface by dropping method was investigated using surface tension measurement (STm), Brewster angle microscopy (BAM), and fluorescence microscopy (FM). STm showed strong condensation effect of Chol in fluidic DPPC monolayer. Excess area (S<sub>ex</sub>) from mean mixing state of DPPC and Chol was about twice larger than that by general compression method in the range from xC = 0.2 to 0.4 (xC: mole fraction of Chol). BAM and FM images showed clearly that the fluidic DPPC monolayer changed to condensed rigid monolayer due to the condensation effect of Chol. At more than xC = 0.3 DPPC-Chol mixed monolayer changed to condensed state similar to the Chol monolayer. These results support previous reports by compression method that Chol molecule demonstrates the strong condensation effect to the fluidic monolayer and also indicate that dropping method enables to form unique monolayer on the water surface. 展开更多
关键词 DPPC-Chol Mixed Monolayer dropping method Surface Tension Measurement Brewster Angle Microscopy Fluorescence Microscopy Condensation Effect
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Validation for Microbial Limit Test Method of Compound Yu E Nose Drops
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作者 Renhui YANG Peixue CAO +1 位作者 Zhen ZENG Xiangling QU 《Agricultural Biotechnology》 CAS 2019年第5期125-128,共4页
[Objectives] This study was conducted to establish a method for microbial limit test of Compound Yu E Nose Drops.[Methods] According to the Chinese Pharmacopoei (General Rules in the fourth part of the 2015 edition),t... [Objectives] This study was conducted to establish a method for microbial limit test of Compound Yu E Nose Drops.[Methods] According to the Chinese Pharmacopoei (General Rules in the fourth part of the 2015 edition),the microbial limit test method for Compound Yu E Nose Drops was verified.[Results] Compound Yu E Nose Drops has a strong inhibitory effect on Staphylococcus aureus and Bacillus subtilis,and the inhibitory activity was significantly eliminated after increasing the diluent (1∶ 20).The recoveries were all in the range of 0.5-2.0 when the total quantities of aerobic microbes were determined by the dilution method (1∶ 20).When the total quantities of mould and yeast were determined by the conventional method,the recoveries were both in the range of 0.5-2.0.When examining control bacteria,Escherichia coli,S.aureus and Pseudomonas aeruginosa can all be detected in the test groups by the test liquid dilution method.[Conclusions] For Compound Yu E Nose Drops,the total quantities of aerobic microbe can be counted by the dilution method;the quantities of mould and yeast can be examined by the conventional plate method;and the conventional method can be used for control microbe examination. 展开更多
关键词 COMPOUND Yu E NOSE dropS MICROBIAL LIMIT test DILUTION method
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Comparative Study of Structural, Optical and Electrical Properties of SnO<sub>2</sub>Thin Film Growth via CBD, Drop-Cast and Dip-Coating Methods
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作者 Md. Tareq Rahman Zubair Ahmed +6 位作者 Md. Johurul Islam Kamaruzzaman Mst. Toma Khatun Md. Abdul Gafur Md. Shahriar Bashar Md. Monjarul Alam 《Materials Sciences and Applications》 2021年第12期578-594,共17页
Tin oxide (SnO<sub>2</sub>) thin films were deposited on glass substrate by Chemical Bath Deposition (CBD), Drop-Cast and Dip-Coating method. The thin films were post-annealed at 500&deg;C for 2 hours.... Tin oxide (SnO<sub>2</sub>) thin films were deposited on glass substrate by Chemical Bath Deposition (CBD), Drop-Cast and Dip-Coating method. The thin films were post-annealed at 500&deg;C for 2 hours. The structural, optical, and electrical properties of the SnO<sub>2</sub> thin films were investigated by using XRD, FTIR, SEM, EDX, UV-Vis spectroscopy, and Electrometer experiment. The XRD patterns of SnO<sub>2</sub> thin films deposited on glass substrate by CBD method, Drop-Cast method and Dip-Coating method showed cubic, tetragonal and amorphous structures respectively. The FTIR spectrum exhibited the strong presence of SnO<sub>2</sub> with the characteristic vibrational mode of Sn-O-Sn. The SEM analysis was observed that the surface morphology of the thin films toughly depends on the deposition methods of the SnO<sub>2</sub> thin films. EDX measurement confirmed that the thin films are the composition of Tin (Sn) and Oxygen (O<sub>2</sub>). The optical band gap of SnO<sub>2 </sub>thin films deposited by CBD method, Drop-Cast method and Dip-Coating method is found to be 3.12 eV, 3.14 eV and 3.16 eV respectively. Thin films deposited by Dip-Coating method showed the highest band gap. The electrical results confirmed that the SnO<sub>2</sub> thin films are good conductors and pursued Ohm’s Law. These properties of the SnO<sub>2</sub> thin films brand are appropriate for application in solar cell assembly, gas sensor devices and transparent electrodes of panel displays. 展开更多
关键词 SnO2 Thin Film CBD drop-Cast and Dip-Coating method Electrical
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烟幕干扰弹投放策略问题的研究
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作者 蔡志杰 《数学建模及其应用》 2026年第1期42-52,共11页
本文研究烟幕干扰弹遮蔽来袭导弹问题.对于一枚烟幕干扰弹和一枚来袭导弹的情形,给出了烟幕遮蔽导弹的快速判别方法,采用改进二分法快速计算有效遮蔽时长.对不同数量的无人机、携带烟幕干扰弹及来袭导弹分别建立最优策略模型,并给出了... 本文研究烟幕干扰弹遮蔽来袭导弹问题.对于一枚烟幕干扰弹和一枚来袭导弹的情形,给出了烟幕遮蔽导弹的快速判别方法,采用改进二分法快速计算有效遮蔽时长.对不同数量的无人机、携带烟幕干扰弹及来袭导弹分别建立最优策略模型,并给出了近似求解方法.最后对竞赛论文给出简要的评述. 展开更多
关键词 运动模型 遮蔽判别模型 改进二分法 投放策略模型
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茶水中痕量重金属快速富集装置及LIBS信号增强方法研究
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作者 付兴兰 贺攀毓 +3 位作者 王成浩 姬瑞晗 安霆 李光林 《西南大学学报(自然科学版)》 北大核心 2026年第4期227-238,共12页
针对激光诱导击穿光谱(Laser-Induced Breakdown Spectroscopy,LIBS)检测茶水中痕量重金属存在的样品富集速度慢、液体飞溅、光谱信号弱和检测灵敏度低等问题,研制了一种基于干滴法的茶水痕量重金属快速富集装置,结合金银纳米粒子(Gold ... 针对激光诱导击穿光谱(Laser-Induced Breakdown Spectroscopy,LIBS)检测茶水中痕量重金属存在的样品富集速度慢、液体飞溅、光谱信号弱和检测灵敏度低等问题,研制了一种基于干滴法的茶水痕量重金属快速富集装置,结合金银纳米粒子(Gold and Silver Nanoparticles,Au-AgNPs)改性的聚丙烯腈(Polyacrylonitrile,PAN)纳米纤维膜,增强了LIBS光谱信号,提高了茶水中痕量重金属检测的灵敏度。实验结果表明:茶水痕量重金属快速富集装置供液模块的平均相对误差为4.6%,温度控制的平均相对误差为3.1%。在富集装置最佳参数为加热温度60℃、茶水用量0.6 mL、供液速度2.0 mL/h时,Cr和Cu的定标曲线R^(2)分别为0.994和0.996,检测限(Limit of Detection,LOD)分别为3μg/L和7μg/L。选取我国7种不同类型的市售茶(花茶、绿茶、青茶、白茶、黄茶、红茶、黑茶)作为真实样本进行验证,实验结果表明:Cr和Cu浓度检测的平均相对误差分别为5.9%和6.4%,与电感耦合等离子体质谱(Inductively Coupled Plasma Mass Spectrometry,ICP-MS)检测结果相当,可为LIBS技术在茶水重金属检测中的应用提供方法支撑。 展开更多
关键词 激光诱导击穿光谱 静电纺丝 纳米粒子 干滴法 痕量重金属 装置
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基于落锤法的橡胶护舷抗冲击性能试验与模拟研究
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作者 李璐 郭宇 +5 位作者 王立成 宋世庆 刘豪 施海涛 刘成龙 马玉祥 《水道港口》 2026年第1期109-114,共6页
为解决现有测试系统难以实现对橡胶护舷进行均匀冲击的问题,提出了一种基于落锤法的护舷抗冲击性能测试装置及测试方法,并采用此装置和方法对缩尺护舷模型开展了抗冲击性能试验。通过改变落锤高度控制冲击速度,共设计了4种冲击速度工况... 为解决现有测试系统难以实现对橡胶护舷进行均匀冲击的问题,提出了一种基于落锤法的护舷抗冲击性能测试装置及测试方法,并采用此装置和方法对缩尺护舷模型开展了抗冲击性能试验。通过改变落锤高度控制冲击速度,共设计了4种冲击速度工况。试验结果表明:随着冲击高度的增加,护舷模型的反力逐渐增大,吸能量也逐渐增大。对于直径300 mm、长度500 mm的圆柱体试件,当冲击高度为400 mm时,模型最大变形可达到140.5 mm,最大反力达到38.49 kN,最大吸能量为2377.41 J。进一步建立了橡胶护舷落锤冲击试验的有限元数值模型,对冲击试验过程开展了数值模拟分析,对比表明数值结果与试验结果吻合较好。 展开更多
关键词 橡胶护舷 冲击性能 落锤法 吸能量 ANSYS软件 测试装置
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Direct Numerical Simulation of Secondary Breakup of Liquid Drops 被引量:9
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作者 刘静 徐旭 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第2期153-161,共9页
This article studies numerically a familiar important phenomenon in spray combustion which is deformation and breakup of liquid drops in gas flow. The SIMPLER method is used to solve the two-dimensional (2D) unstead... This article studies numerically a familiar important phenomenon in spray combustion which is deformation and breakup of liquid drops in gas flow. The SIMPLER method is used to solve the two-dimensional (2D) unsteady axisymmetric Navier-Stokes equations for both the drop and the ambient gas flow. The level set method is applied to capturing the liquid/gas interface. Through calculation are obtained four typical breakup modes--oscillation, bag breakup, sheet stripping breakup and shear breakup governed by four non-dimensional numbers which are gas Weber number (Weg), liquid Reynolds number (Rel), gas Reynolds number (Reg) and density ratio (γ). Their effects upon each mode are analyzed. The results indicate that among the four numbers, Weg is of the highest importance with Rel, Reg and γfollowing up. By widening the range of the density ratio up to 1 000, the breakup mode is discovered to be so complicated that a new one called multimode breakup mode turns up. This mode contains the shearing breakup and piercing breakup, which successively happen. The calculation results agree well with what is observed from the experiments. 展开更多
关键词 two phase flow drop breakup level set method SIMPLER method numerical simulation
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基于加权递推最小二乘法的电能表误差分析模型
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作者 廖贺 刘飞 +2 位作者 严永辉 吴甲 喻伟 《电力大数据》 2026年第2期80-88,共9页
为精准估计电能表计量误差,提出一种基于加权递推最小二乘法的电能表运行误差分析模型。首先,基于标定电流法识别轻载用户表,通过统计其在时间窗口内的轻载占比率,将多个轻载用户表合并为一个“虚拟用户表”,剔除误差偏高的轻载量测数据... 为精准估计电能表计量误差,提出一种基于加权递推最小二乘法的电能表运行误差分析模型。首先,基于标定电流法识别轻载用户表,通过统计其在时间窗口内的轻载占比率,将多个轻载用户表合并为一个“虚拟用户表”,剔除误差偏高的轻载量测数据,同时保留整体数据完整性;其次,基于压降法构建线损模型,利用台区总表与各用户表的电压、电流数据直接计算线路压降引起的可变线损;然后,根据能量守恒定律,建立用户表运行误差分析线性方程;最后,基于加权递推最小二乘法求解用户表误差率,引入可变遗忘因子,动态调节历史数据权重,估算电能表分表误差。实验结果表明,相较于固定线损模型和动态线损模型,所提模型可有效提高电能表误差估算的精确度,对已知超差表的检出率达100%。 展开更多
关键词 电能表 误差分析 压降法线损 能量守恒 加权递推最小二乘法
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密相气力输送给料口加速段稳态压降计算系数分析
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作者 张亦明 周甲伟 +2 位作者 魏烨东 李永鑫 高魁东 《过程工程学报》 北大核心 2026年第2期139-149,共11页
以较低成本使物料能够连续稳定输送是气力输送系统设计的目标。本工作以炭黑母粒为实验物料,基于气力输送循环试验台,对密相气力输送给料口加速段中加速压降和稳态压降的特性进行了研究。实验过程中通过改变旋转阀频率,得到了固气比为12... 以较低成本使物料能够连续稳定输送是气力输送系统设计的目标。本工作以炭黑母粒为实验物料,基于气力输送循环试验台,对密相气力输送给料口加速段中加速压降和稳态压降的特性进行了研究。实验过程中通过改变旋转阀频率,得到了固气比为12~32时给料口加速段压降的变化数据,并采用经验公式和响应面法,对给料口加速段总压降进行了进一步分析和预测。结果表明,料靴压降在料靴加速段L12的压降变化中占主导地位,且两者均随固气比增大近似线性增加。在给料口加速段L23中,基于响应面法建立了压降计算系数(固相摩擦系数)预测模型,当固气比为12~26时,模型预测压降与实验值的相对误差在15%以内;当固气比增至26~32时,压降呈现不稳定波动特征,此时基于附加压降法的预测方法已不再适用。 展开更多
关键词 气力输送 两相流 响应面法 压降 固相摩擦系数 固气比
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火力发电机组汽轮机局部参数扰动能效及子系统性能诊断技术
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作者 麻克栋 《科技创新与应用》 2026年第4期185-188,共4页
为提升火力发电机组汽轮机运行的稳定性和经济性,探究汽轮机局部参数扰动能效及子系统性能诊断技术的应用。在局部参数扰动能效诊断中,使用等效热降法计算汽轮机的热耗率、标准煤耗和煤耗偏差。结合案例的耗差分析,得出1#高加上端差运... 为提升火力发电机组汽轮机运行的稳定性和经济性,探究汽轮机局部参数扰动能效及子系统性能诊断技术的应用。在局部参数扰动能效诊断中,使用等效热降法计算汽轮机的热耗率、标准煤耗和煤耗偏差。结合案例的耗差分析,得出1#高加上端差运行性能偏低导致煤耗率升高的结论,并初步认为是加热器故障所致。为进一步诊断故障,使用故障树分析法诊断回热系统性能,使用模糊处理与隶属度分析诊断凝汽器性能。结果表明,诊断结果与案例事实一致,验证该诊断技术的可用性。 展开更多
关键词 火力发电机组 等效热降法 凝汽器过冷度 故障树分析法 扰动能效
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ROADM网络业务电再生中继规划方法探讨
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作者 赵满良 唐晓强 +1 位作者 王浩 刘树聪 《邮电设计技术》 2026年第3期58-63,共6页
ROADM全光网络的业务电再生中继规划的影响因素和规划方法有多种。主要从业务可靠性、电再生中继配置规模的角度分析论证,提出在进行业务电再生中继规划时,有必要设置合理的最大链路同时故障条数值。通过对电再生中继规划所采用的穷举... ROADM全光网络的业务电再生中继规划的影响因素和规划方法有多种。主要从业务可靠性、电再生中继配置规模的角度分析论证,提出在进行业务电再生中继规划时,有必要设置合理的最大链路同时故障条数值。通过对电再生中继规划所采用的穷举法和极限法的基本原理及其仿真结果进行对比分析,总结出这2种规划仿真方法的优劣。 展开更多
关键词 ROADM 电再生中继 规划方法
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蔬菜钵苗移栽机夹茎式取投苗装置的优化设计与试验
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作者 李红双 朱天一 《农机化研究》 北大核心 2026年第4期43-51,共9页
针对现有蔬菜钵苗取投苗装置存在作业效率低、伤苗率高的问题,设计了一种夹茎式六杆取投苗装置,能够保证在不损伤钵苗的前提下实现快速取投苗。首先,基于取投苗作业轨迹关键点设计了各关键部件结构参数,并建立其运动学模型;其次,根据运... 针对现有蔬菜钵苗取投苗装置存在作业效率低、伤苗率高的问题,设计了一种夹茎式六杆取投苗装置,能够保证在不损伤钵苗的前提下实现快速取投苗。首先,基于取投苗作业轨迹关键点设计了各关键部件结构参数,并建立其运动学模型;其次,根据运动学模型使用MatLab软件编写取投苗装置的优化分析程序,分析出连杆参数对装置运动特性的影响。设定参数优化目标和约束条件,采用逐次逼近法对关键部件进行参数优化,得到一组最优连杆参数组合:l_(AB)=76 mm、l_(BC)=256 mm、l_(CD)=140 mm、l_(AD)=300 mm、l_(DE)=270 mm、θ5=85°;最后,以优化后的最优连杆参数组合设计试验样机进行虚拟仿真验证,并以苗龄45 d、基质含水率50%的茄子钵苗作为试验对象,进行样机测试。结果表明:虚拟仿真的轨迹、速度和加速度曲线与优化后理论曲线基本一致,试验样机测试的取苗成功率提升至96.83%,与传统取苗装置相比提升5.05个百分点,投苗成功率95.87%,伤苗率2.83%,能够满足蔬菜钵苗移栽机的实际作业要求。 展开更多
关键词 蔬菜钵苗移栽机 取投苗装置 运动学模型 逐次逼近法 参数优化 夹茎式
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Spherical silicon solar cell with reflector cup fabricated by decompression dropping method
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作者 MINEMOTO Takashi OKAMOTO Chikao +2 位作者 MUROZONO Mikio TAKAKURA Hideyuki HAMAKAWA Yoshihiro 《Rare Metals》 SCIE EI CAS CSCD 2006年第Z1期121-126,共6页
A spherical Si solar cell with a reflector cup was successfully fabricated by a dropping method at decompression state. In the dropping method, melted Si droplets were instilled at decompression state (0.5×105 Pa... A spherical Si solar cell with a reflector cup was successfully fabricated by a dropping method at decompression state. In the dropping method, melted Si droplets were instilled at decompression state (0.5×105 Pa) to reduce crystal growth rate, dominating crystal quality such as dislocation density in crystal grains. Spherical Si solar cells were fabricated using the spherical Si crystals with a diameter of 1 mm and then mounted on a reflector cup. The current-voltage measurement of the solar cell shows an energy conversion efficiency of 11.1% (short-circuit current density (Jsc): 24.7 mA·cm-2, open-circuit voltage: 601 mV, fill factor: 74.6%). Minority carrier diffusion length determined by surface photovoltage method was 98 μm. This value can be enhanced by the improvement of crystal quality of spherical Si crystals. These results demonstrate that spherical Si crystals fabricated by the dropping method has a great potential for substrate material of high-efficiency and low-cost solar cells. 展开更多
关键词 spherical Si solar cell dropping method decompression state
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Drop test and crash simulation of a civil airplane fuselage section 被引量:18
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作者 Liu Xiaochuan Guo Jun +2 位作者 Bai Chunyu Sun Xiasheng Mou Rangke 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第2期447-456,共10页
Crashworthiness of a civil airplane fuselage section was studied in this paper. Firstly, the failure criterion of a rivet was studied by test, showing that the ultimate tension and shear failure loads were obviously a... Crashworthiness of a civil airplane fuselage section was studied in this paper. Firstly, the failure criterion of a rivet was studied by test, showing that the ultimate tension and shear failure loads were obviously affected by the loading speed. The relations between the loading speed and the average ultimate shear, tension loads were expressed by two logarithmic functions, Then, a vertical drop test of a civil airplane fuselage section was conducted with an actual impact velocity of 6.85 m/s, meanwhile the deformation of cabin frame and the accelerations at typical locations were measured. The finite element model of a main fuselage structure was developed and validated by modal test, and the error between the calculated frequencies and the test ones of the first four modes were less than 5%. Numerical simulation of the drop test was performed by using the LS-DYNA code and the simulation results show a good agreement with that of drop test. Deforming mode of the analysis was the same as the drop test; the maximum average rigid acceleration in test was 8.8 l g while the calculated one was 9.17g, with an error of 4.1%; average maximum test deformation at four points on the front cabin floor was 420 mm, while the calculated one was 406 mm, with an error of 3.2%; the peak value of the calculated acceleration at a typical location was 14.72g, which is lower than the test result by 5.46%; the calculated rebound velocity result was greater than the test result 17.8% and energy absorption duration was longer than the test result by 5.73%. 展开更多
关键词 Civil airplane drop test Finite element method Fuselage section Rivet failure
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