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惰性粒子 2

机械性能 2

气体分布板 2

X射线阻射性 1

三流体喷嘴喷雾干燥技术 1

冷冻萃取 1

喷雾干燥 1

图像解析法 1

多功能团簇体填料 1

差分方程 1

干燥应力 1

干燥性能 1

干缩异向性 1

开孔形状 1

开孔率 1

开孔结构 1

弦向应变 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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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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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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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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Utilisation of waste heat from exhaust gases of drying process

Olga P. Arsenyeva,Lidija Čuček,Leonid L. Tovazhnyanskyy,Petro O. Kapustenko,Yana A. Savchenko,Sergey K. Kusakov,Oleksandr I. Matsegora

《化学科学与工程前沿（英文）》 2016年第10卷第1期页码 131-138 doi: 10.1007/s11705-016-1560-8

摘要： Nowadays a lot of low-grade heat is wasted from the industry through the off- and flue-gasses with different compositions. These gases provide the sensitive heat with utilisation potential and latent heat with the components for condensation. In this paper, process integration methodology has been applied to the partly condensed streams. A hot composite curve that represents the gas mixture cooling according to equation of state for real gases was drawn to account the gas-liquid equilibrium. According to the pinch analysis methodology, the pinch point was specified and optimal minimal temperature difference was determined. The location of the point where gas and liquid phases can be split for better recuperation of heat energy within heat exchangers is estimated using the developed methodology. The industrial case study of tobacco drying process off-gasses is analysed for heat recovery. The mathematical model was developed by using MathCad software to minimise the total annualised cost using compact plate heat exchangers for waste heat utilisation. The obtained payback period for the required investments is less than six months. The presented method was validated by comparison with industrial test data.

关键词： exhaust gas waste heat process integration plate heat exchanger

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高频真空木材干燥的模糊神经网络控制方法研究

姜滨,孙丽萍,曹军,周正

《中国工程科学》 2014年第16卷第4期页码 17-20

摘要：

高频真空木材干燥是一种干燥速度快、能源消耗低、环境污染小的新型联合干燥技术。在木材高频真空联合干燥过程的理论分析基础上，针对神经网络方法建立的木材干燥模型，设计了木材干燥模糊控制器和模糊神经网络控制器。对模糊控制和模糊神经网络两种控制方法进行了仿真实验，结果表明模糊神经网络方法控制效果更好，如温度上升快，控制精度高，稳定性好。模糊神经网络控制方法对实现木材干燥过程的全自动控制具有重要研究意义。

关键词：高频真空木材干燥模糊神经网络

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气体分布板开孔结构对流化床干燥性能的影响

刘巍,汤文成

《中国工程科学》 2006年第8卷第2期页码 47-50

摘要：

针对惰性粒子流化床干燥器，以洗衣粉悬浮液为对象，先后进行了气体分布板开直孔和开斜孔的流化干燥实验。通过测定干燥器的流体力学特性曲线，以及在相同进料量、进风温度、进风速度或惰性粒子直径条件下的体积传热系数曲线和热效率曲线，考察和分析了气体分布板两种不同的开孔结构对干燥器流体力学和传热性能的影响。结果表明，气体分布板开斜孔的床内气流阻力要高于开直孔的气流阻力，但其体积传热系数和热效率相对较高，即斜孔较直孔更加有利于床内传热。在此基础上，对惰性粒子流化床干燥器的生产调节措施进行了初步探讨。

关键词：气体分布板开孔结构惰性粒子流化床干燥性能

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锯材高频-对流联合加热干燥传热传质数学模型

贾潇然,赵景尧,蔡英春

《中国工程科学》 2014年第16卷第4期页码 106-112

摘要：

本文以多孔介质传热传质理论为基础，结合高频-对流联合加热干燥过程中热质传递的机理及特性，通过质量、动量、能量守恒方程等建立了高频-对流联合加热干燥过程中锯材热质传递数学模型并给出相应定解条件。模型中每个自变量及因变量都有独立的控制方程，利用控制容积法建立相应控制方程的差分格式，将耦合偏微分方程按步骤解耦，以便于利用Matlab 或FORTRAN等编程求解时，达到每个自变量均可以独立求解的目的。

关键词：锯材高频-对流干燥数学模型差分方程

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A comprehensive review of greenhouse shapes and its applications

Ravinder Kumar SAHDEV,Ashwani Kumar DHINGRA,Mahesh KUMAR

《能源前沿（英文）》 2019年第13卷第3期页码 427-438 doi: 10.1007/s11708-017-0464-8

摘要： Greenhouse technology is a practical option for the production and drying of agricultural products in controlled environment. For the successful design of a greenhouse, the selection of a suitable shape and orientation is of great importance. Of various shapes of greenhouses, the even-span roof and the Quonset shape greenhouses are the most commonly used for crop cultivation and drying. The orientation of greenhouses is kept east–west for maximum utilization of solar radiations. Hybrid and modified greenhouse dryers have been proposed for drying of products. The agricultural products dried in greenhouses are found to be better in quality as compared to open sun drying because they are protected from dust, rain, insects, birds and animals. Moreover, various greenhouses shapes along with their applications have been reviewed.

关键词： greenhouse shapes drying solar energy agriculture products orientation

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Multifractal characteristics of cylindrical sludge drying

Weiyun WANG, Aimin LI,

《环境科学与工程前沿（英文）》 2009年第3卷第4期页码 464-469 doi: 10.1007/s11783-009-0040-5

摘要： This paper analyzes dewatered sludge drying using the multifractal theory. The drying rates of cylindrical sludge with equal masses but different cross-sectional diameters was studied, from which multifractal parameters such as partition function and quality exponent were obtained. The parameters acquired were used to calculate the multifractal singularity spectrum and indicate the presence of multifractal characteristics. The smaller cross-sectional diameters of the sludge were found to be non-homogeneous, and required quantitative methods to analyze.

关键词： multifractal characteristic multifractal singularity spectrum sewage sludge drying

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Possible solutions for sludge dewatering in China

Wei WANG, Yuxiang LUO, Wei QIAO,

《环境科学与工程前沿（英文）》 2010年第4卷第1期页码 102-107 doi: 10.1007/s11783-010-0001-z

摘要： In China, over 1.43×10 tons of dewatered sewage sludge, with 80% water content, were generated from wastewater treatment plants in 2007. About 60% of the COD removed during the wastewater treatment process becomes concentrated as sludge. Traditional disposal methods used by municipal solid waste treatment facilities, such as landfills, composting, or incineration, are unsuitable for sludge disposal because of its high water content. Disposal of sludge has therefore become a major focus of current environmental protection policies. The present status of sludge treatment and disposal methodology is introduced in this paper. Decreasing the energy consumption of sludge dewatering from 80% to 50% has been a key issue for safe and economic sludge disposal. In an analysis of sludge water distribution, thermal drying and hydrothermal conditioning processes are compared. Although thermal drying could result in an almost dry sludge, the energy consumption needed for this process is extremely high. In comparison, hydrothermal technology could achieve dewatered sewage sludge with a 50%–60% water content, which is suitable for composting, incineration, or landfill. The energy consumption of hydrothermal technology is lower than that required for thermal drying.

关键词： sewage sludge disposal water content thermal drying hydrothermal conditioning

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冷冻-萃取/真空干燥法制备坚固和耐疲劳的聚酰亚胺纤维气凝胶及其增强阻燃性复合材料 Article

姚恺清, 宋崇虎, 方红, 王峰, 陈炼, 蒋少华, 查国君, 侯豪情

《工程（英文）》 2023年第21卷第2期页码 152-161 doi: 10.1016/j.eng.2021.08.024

摘要：

在现代新材料的快速发展中，用节能、省时、低成本和简便的新型方法制备具有优良机械性能和热学性能的轻质、低密度和高孔隙率气凝胶十分必要。在本工作中，我们使用短切电纺聚酰亚胺（PI）纤维作为支撑骨架，通过开发出一种无需特殊干燥方法的真空干燥（VD）与冷冻-萃取相结合的方法，制备出高性能PI 纤维气凝胶（PIFAs）。所得PIFAs 具有低密度（≤52.8 mg⋅cm⁻³）和高孔隙率（>96%）。该PIFA在至少20 000 次的循环压缩过程中展现出高度的耐疲劳性及低能量损失系数。密度为39.1 mg⋅cm⁻³的PIFA具有40.4 mW⋅m⁻¹⋅K⁻¹的热导率。通过进一步使用聚硅氮烷对PIFAs复合改性后，其具备更强的耐火性和氮气氛围中的高残留率（>70%）。这些优异的性能使PIFAs 及其复合材料成为可应用于建筑工业、航空和航天工业轻质材料、隔热和防火层以及高温反应催化剂载体的可选材料。此外，本工作中提出的冷冻-萃取/VD法因其节能、省时和节约成本而可被拓展用于制备其他材料。

关键词：聚酰亚胺气凝胶冷冻萃取真空干燥机械性能隔热性能防火性能

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Fabrication of cellulose aerogel from wheat straw with strong absorptive capacity

Jian LI,Caichao WAN,Yun LU,Qingfeng SUN

《农业科学与工程前沿（英文）》 2014年第1卷第1期页码 46-52 doi: 10.15302/J-FASE-2014004

摘要： An effectively mild solvent solution containing NaOH/PEG was employed to dissolve the cellulose extracted from the wheat straw. With further combined regeneration process and freeze-drying, the cellulose aerogel was successfully obtained. Scanning electron microscope, X-ray diffraction technique, Fourier transform infrared spectroscopy, and Brunauer-Emmett-Teller were used to characterize this cellulose aerogel of low density (about 40 mg·cm ) and three-dimensional network with large specific surface area (about 101 m ·g ). Additionally, with a hydrophobic modification by trimethylchlorosilane, the cellulose aerogel showed a strong absorptive capacity for oil and dye solutions.

关键词： cellulose aerogel absorptive capacity waste wheat straw freeze-drying

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Fresh and hardened properties of high-strength concrete incorporating byproduct fine crushed aggregate as partial replacement of natural sand

Dammika P. K. WELLALA, Ashish Kumer SAHA, Prabir Kumar SARKER, Vinod RAJAYOGAN

《结构与土木工程前沿（英文）》 2021年第15卷第1期页码 124-135 doi: 10.1007/s11709-020-0673-9

摘要： This paper presents the fresh and hardened properties of high-strength concrete comprising byproduct fine crushed aggregates (FCAs) sourced from the crushing of three different types of rocks, namely granophyre, basalt, and granite. The lowest void contents of the combined fine aggregates were observed when 40% to 60% of natural sand is replaced by the FCAs. By the replacement of 40% FCAs, the slump and bleeding of concrete with a water-to-cement ratio of 0.45 decreased by approximately 15% and 50%, respectively, owing to the relatively high fines content of the FCAs. The 28 d compressive strength of concrete was 50 MPa when 40% FCAs were used. The slight decrease in tensile strength from the FCAs is attributed to the flakiness of the particles. The correlations between the splitting tensile and compressive strengths of normal concrete provided in the AS 3600 and ACI 318 design standards are applicable for concrete using the FCAs as partial replacement of sand. The maximum 56 d drying shrinkage is 520 microstrains, which is significantly less than the recommended limit of 1000 microstrains by AS 3600 for concrete. Therefore, the use of these byproduct FCAs can be considered as a sustainable alternative option for the production of high-strength green concrete.

关键词： fine crushed aggregates quarry dust compressive strength splitting tensile strength drying shrinkage