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DX桩 2

惰性粒子 2

机械性能 2

气体分布板 2

Lagrange方程 1

X射线阻射性 1

三流体喷嘴喷雾干燥技术 1

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Soybean drying characteristics in microwave rotary dryer with forced convection

Ruifang WANG, Zhanyong LI, Yanhua LI, Jingsheng YE

《化学科学与工程前沿（英文）》 2009年第3卷第3期页码 289-292 doi: 10.1007/s11705-009-0022-y

摘要： A new hybrid drying technique by combining microwave and forced convection drying within a rotary drum, i.e., microwave rotary drying, was developed with the purpose to improve the uniformity of microwave drying. In a laboratory microwave rotary dryer, rewetted soybean was utilized as experimental material to study the effects of drum rotating speed, ventilation flow rate, and specific microwave power on the drying kinetics and cracking ratio of soybean. It was found that, with rotation, the cracking ratio can be lowered but without distinct improvement in the drying rate. Increasing ventilation flow rate and specific microwave power can improve the drying rate, but the cracking ratio also increases as a negative result. The cracking ratio lower than 10% can be attained for ventilation flow rate lower than 2.0 m ·h or specific microwave energy lower than 0.4 kW·kg in the present experiments.

关键词： cracking microwave rotary drying soybean

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Design and analysis of a new high frequency double-servo direct drive rotary valve

Muzhi ZHU,Shengdun ZHAO,Jingxiang LI

《机械工程前沿（英文）》 2016年第11卷第4期页码 344-350 doi: 10.1007/s11465-016-0406-x

摘要：

Researchers have investigated direct drive valve for many years to solve problems, such as fluid force imbalance and switching frequency. The structure of the rotary valve has received considerable research interest because of its favorable dynamic properties and simple structure. This paper studied the high frequency double-servo direct drive rotary valve (DDRV), and proposed a novel structure and drive method satisfying high reversing frequency and adequate quantity of flow. Servo motors are integrated into the valve by the innovative structure, which is designed to equilibrate the unbalanced radial fluid force with the symmetric distributed oil ports. Aside from the fast reversing function of the valve, the DDRV presented high performance in linearity of the flow quantity and valve opening as a result of the fan-shaped flow ports. In addition, a computational fluid dynamics (CFD) method based on Fluent was conducted to verify the flux regulation effect of the height change of the adjustable boss.

关键词： direct drive rotary valve computational fluid dynamics (CFD) flow regulation

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DX挤扩灌注桩技术在铁路桥梁工程中的应用

张德华,王梦恕

《中国工程科学》 2009年第11卷第7期页码 92-96

摘要：

DX桩是近年来新兴的一种变截面新桩型。是在钻孔灌注桩的基础上，使用专用挤扩设备在桩底和桩身挤扩成为支盘状，然后浇灌混凝土后形成的桩身、分承力盘和桩根共同承载的桩型。DX桩可较大幅度提高单桩承载力。试验表明单桩承载力比同等条件下的直孔灌注桩提高80 %以上。DX桩可在粘性土、粉土、砂土层、强风化岩、残积土中挤扩承力盘，也可在卵砾石层的上层面挤扩成盘，更适宜在粘性土、粉土或砂土交互分层的地基中使用。DX桩的桩身直径可为400～2 000 mm,桩长可达60多米。是一种值得推广应用的新桩型，已在高层建筑、公路桥

关键词： DX桩旋挖挤扩灌注桩承载力

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Effectiveness analysis and optimum design of the rotary regenerator for thermophotovoltaic (TPV) system

Xi WU, Hong YE, Jianxiang WANG, Jie HE, Jian YANG

《能源前沿（英文）》 2012年第6卷第2期页码 193-199 doi: 10.1007/s11708-012-0184-z

摘要： The influence of the period of rotation on the effectiveness of the thermophotovoltaic (TPV) rotary regenerator was theoretically and experimentally investigated. It was found that the deviations of the theoretical results from the experimental ones decrease with the increase of the period of rotation. To the TPV system of 10 kW combustion power, the deviation is 3.5% when the rotation period is 3 s; while the deviation decreases to 1.5% when the rotation period increases to 15 s. The deviation could be mainly attributed to the cold and hot fluids carryover loss which was not considered in the model. With a new model taking account of the carryover loss established, the predicted results were greatly improved. Based on the modified model, the influence of geometrical parameters of rotary regenerator on the effectiveness was analyzed for TPV systems of various combustion power. The results demonstrate that the effectiveness increases with the increase of the rotary regenerator diameter and height, while fluid carryover loss increases at the same time, which weakens the impact of geometrical parameters.

关键词： thermophotovoltaic (TPV) system rotary regenerator effectiveness carryover loss

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Performance of rolling piston type rotary compressor using fullerenes (C70) and NiFe

Ruixiang WANG,Yihao ZHANG,Yi LIAO

《能源前沿（英文）》 2020年第14卷第3期页码 644-648 doi: 10.1007/s11708-017-0453-y

摘要： A novel way for a compressor to improve its coefficient of performance was proposed in this paper. Fullerenes (C70) and NiFe O nanocomposites were modified by span 80 and dispersed in refrigeration oil by solid grinding (SG). Besides, the tribological properties of the nanocomposites were investigated using a four ball friction tester. The results show that when the mass concentration of fullerenes nanocomposite is higher than 60 ppm and the concentration of nano-oil is 2 g/L, the friction coefficient decreases from 0.13 to 0.06 which means the wear is reduced. The coefficient of performance of the compressor under the air conditioning test condition can be raised by 1.23%.

关键词： rotary compressor friction coefficient nanocomposite materials coefficient of performance fullerenes (C70)

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Co-pyrolysis of sludge and kaolin/zeolite in a rotary kiln: Analysis of stabilizing heavy metals

《环境科学与工程前沿（英文）》 2022年第16卷第7期 doi: 10.1007/s11783-021-1488-1

摘要：

• Adding kaolin/zeolite promotes the formation of stable heavy metals.

关键词： Co-pyrolysis Sewage sludge Heavy metals Rotary kiln Immobilization mechanism

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A solar assisted heat pump drying system for grain in-store drying

Haifeng LI, Yanjun DAI, Jianguo DAI, Xibo WANG, Lei WEI,

《能源前沿（英文）》 2010年第4卷第3期页码 386-391 doi: 10.1007/s11708-010-0003-3

摘要： For grain in-store drying, a solar assisted drying process has been developed, which consists of a set including a solar-assisted heat pump, a ventilation system, a grain stirrer, etc. In this way, low power consumption, short cycle time and water content uniformity can be achieved in comparison with the conventional method. A solar-assisted heat pump drying system has been designed and manufactured for a practical granary, and the energy consumption performance of the unit is analyzed. The analysis result shows that the solar fraction of the unit is higher than 20%, the coefficient of performance about system (COP) is 5.19, and the specific moisture extraction rate (SMER) can reach 3.05 kg/kWh.

关键词： solar energy heat pump airflow in-store drying

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Novel precision piezoelectric step rotary actuator

LIU Jianfang, YANG Zhigang, ZHAO Hongwei, CHENG Guangming

《机械工程前沿（英文）》 2007年第2卷第3期页码 356-360 doi: 10.1007/s11465-007-0062-2

摘要： A novel piezoelectric (PZT) precision step rotary actuator was developed on the basis of PZT technology. It adopts the principle of bionics and works with an inside anchoring/loosening of the stator and a distortion structure of the uniformly distributed thin flexible hinge to solve problems such as ineffective anchoring/loosening, low step rotary frequency, small travel, poor resolution, low speed and unsteady output. The developed actuator is characterized by high frequency (30 Hz), high speed (380 μrad/s), large travel (>270º), high resolution (1 μrad/step), and work stability. It greatly improves the ability to drive the existing PZT step rotary actuator. The new actuator can be applied in the field of micromanipulation and precision engineering, including precision driving and positioning and optics engineering.

关键词： developed stability ineffective anchoring/loosening technology piezoelectric

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Modeling and analysis of steady-state vibration induced by backlash in servo rotary table

Xiao YANG,Dun LU,Sanli LIU,Jun ZHANG,Wanhua ZHAO

《机械工程前沿（英文）》 2015年第10卷第1期页码 43-47 doi: 10.1007/s11465-015-0327-0

摘要：

Backlash cannot be always avoided in mechanical systems because of wear or looseness. Steady-state vibration may be induced by backlash in closed loop feed drive systems. This paper presents a mathematical model of a servo rotary table, considering the effect of backlash. The accuracy of this model is verified by an experiment. The influences of the parameters, such as position controller gain, velocity controller gain, load and the magnitude of backlash, on steady-state vibration are discussed. The steady-state vibration amplitude increases with the position controller gain, load and the magnitude of backlash. The steady-state vibration frequency increases with the position controller gain and the velocity controller gain, while an increase in load leads to a decrease in the frequency.

关键词： backlash servo rotary table steady-state vibration

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Modeling temperature and moisture dependent emissions of carbon dioxide and methane from drying dairy

Enzhu HU, Pakorn SUTITARNNONTR, Markus TULLER, Scott B. JONES

《农业科学与工程前沿（英文）》 2018年第5卷第2期页码 280-286 doi: 10.15302/J-FASE-2018215

摘要： Greenhouse gas emissions due to biological degradation processes of animal wastes are significant sources of air pollution from agricultural areas. The major environmental controls on these microbe-induced gas fluxes are temperature and moisture content. The objective of this study was to model the effects of temperature and moisture content on emissions of CO and CH during the ambient drying process of dairy manure under controlled conditions. Gas emissions were continuously recorded over 15 d with paired fully automated closed dynamic chambers coupled with a Fourier Transformed Infrared gas analyzer. Water content and temperature were measured and monitored with capacitance sensors. In addition, on days 0, 3, 6, 9, 12 and 15, pH, moisture content, dissolved organic carbon and total carbon (TC) were determined. An empirical model derived from the Arrhenius equation confirmed high dependency of carbon emissions on temperature and moisture content. Results indicate that for the investigated dairy manure, 6.83% of TC was lost in the form of CO and 0.047% of TC was emitted as CH . Neglecting the effect of temperature, the moisture contents associated with maximum gas emissions were estimated as 0.75 and 0.79 g·g for CO and CH , respectively.

关键词： carbon dioxide dairy manure methane moisture temperature

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Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

《环境科学与工程前沿（英文）》 2021年第15卷第6期 doi: 10.1007/s11783-021-1427-1

摘要：

• Sediment desiccation alters morphological characteristics of aquatic sediment.

关键词： Fibrous-root macrophytes Thick-root macrophytes Nutrients removal Wet sediment Dried-rewetted sediment

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旋挖钻机施工钻孔灌注桩的工艺研究

李林,闵峰

《中国工程科学》 2010年第12卷第4期页码 33-36

摘要：

泰州大桥夹江左汊桥主跨采用87.5 m+3×125 m+87.5 m的五跨连续梁桥，水中主墩基础采用-2.0 m桩径的钻孔灌注桩,最大设计桩长为94 m，采用旋挖钻机施工。文章结合泰州大桥的施工实例，阐述了旋挖钻机成孔的工艺原理，按照工艺流程，重点叙述了泥浆配置、安装钻孔、钻机钻进等工艺，并重点总结了旋挖钻机施工钻孔桩的施工特点，为今后类似工程施工提供了借鉴。

关键词：旋挖钻机施工钻孔灌注桩工艺特点

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general parameterized time--frequency transform and its application in the feature extraction of a rotary

Peng ZHOU, Zhike PENG, Shiqian CHEN, Yang YANG, Wenming ZHANG

《机械工程前沿（英文）》 2018年第13卷第2期页码 292-300 doi: 10.1007/s11465-017-0443-0

摘要：

With the development of large rotary machines for faster and more integrated performance, the condition monitoring and fault diagnosis for them are becoming more challenging. Since the time-frequency (TF) pattern of the vibration signal from the rotary machine often contains condition information and fault feature, the methods based on TF analysis have been widely-used to solve these two problems in the industrial community. This article introduces an effective non-stationary signal analysis method based on the general parameterized time–frequency transform (GPTFT). The GPTFT is achieved by inserting a rotation operator and a shift operator in the short-time Fourier transform. This method can produce a high-concentrated TF pattern with a general kernel. A multi-component instantaneous frequency (IF) extraction method is proposed based on it. The estimation for the IF of every component is accomplished by defining a spectrum concentration index (SCI). Moreover, such an IF estimation process is iteratively operated until all the components are extracted. The tests on three simulation examples and a real vibration signal demonstrate the effectiveness and superiority of our method.

关键词： rotary machines condition monitoring fault diagnosis GPTFT SCI

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气体分布板开孔结构对流化干燥滞留率的影响

刘巍,汤文成

《中国工程科学》 2006年第8卷第6期页码 41-43

摘要：

滞留率是确定流化干燥死床点的重要参数。针对气体分布板开直孔和开斜孔的惰性粒子流化床干燥器，以洗衣粉悬浮液为对象，考查了进料量、惰性粒子直径、进风温度、静床高、进风速度以及物料初始浓度对干燥器滞留率的影响，分析了气体分布板开直孔和开斜孔时干燥器滞留率的大小，并以气体分布板开斜孔为例，测定了干燥器的生产能力与板开孔率之间的关系曲线。结果表明，滞留率随进料量和物料初始浓度的提高而增大，随惰性粒子直径、进风温度、静床高和进风速度的提高而减小；若将气体分布板的孔道由直孔改为斜孔，并在此基础上适当增加板的开孔率，可有效降低干燥器的滞留率，提高干燥器的生产能力。

关键词：惰性粒子流化干燥气体分布板开孔形状开孔率滞留率

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Impact drive rotary precision actuator with piezoelectric bimorphs

ZHANG Hongzhuang, ZENG Ping, HUA Shunming, CHENG Guangming, YANG Zhigang

《机械工程前沿（英文）》 2008年第3卷第1期页码 71-75 doi: 10.1007/s11465-008-0008-3

摘要： An impact drive rotary precision actuator with end-loaded piezoelectric cantilever bimorphs is proposed. According to finite element analysis and experiments of the dynamic characteristics of end-loaded piezoelectric cantilever bimorphs, a specific fixed-frequency and adjustable-amplitude is confirmed to control the actuator. The results show that an actuator excited by fixed-frequency and the adjustable-amplitude ramp voltage waveform works with a large travel range (180°), high resolution (1 ?rad), speed (0.2 rad/min) and heavy-load ability (0.02 Nm). With advantages of high-precision positioning ability, simple structure and only one percent the cost of traditional impact drive mechanisms, the actuator is expected to be widely used in precision industries.

关键词： specific fixed-frequency waveform piezoelectric cantilever mechanisms adjustable-amplitude