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9 %~12 % Cr 钢 1

&prime 1

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M23C6 碳化物 1

SiC绝缘侧壁 1

低温铝电解 1

加密 1

惰性阳极 1

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抗冻水凝胶 1

显微结构 1

晶界 1

焊缝 1

聚集诱导发光 1

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An investigation of reaction furnace temperatures and sulfur recovery

S. ASADI, M. PAKIZEH, M. POURAFSHARI CHENAR

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 362-371 doi: 10.1007/s11705-011-1106-z

摘要： In a modern day sulfur recovery unit (SRU), hydrogen sulfide (H S) is converted to elemental sulfur using a modified Claus unit. A process simulator called TSWEET has been used to consider the Claus process. The effect of the H S concentration, the H S/CO ratio, the input air flow rate, the acid gas flow of the acid gas (AG) splitter and the temperature of the acid gas feed at three different oxygen concentrations (in the air input) on the main burner temperature have been studied. Also the effects of the tail gas ratio and the catalytic bed type on the sulfur recovery were studied. The bed temperatures were optimized in order to enhance the sulfur recovery for a given acid gas feed and air input. Initially when the fraction of AG splitter flow to the main burner was increased, the temperature of the main burner increased to a maximum but then decreased sharply when the flow fraction was further increased; this was true for all three concentrations of oxygen. However, if three other parameters (the concentration of H S, the ratio H S/CO and the flow rate of air) were increased, the temperature of the main burner increased monotonically. This increase had different slopes depending on the oxygen concentration in the input air. But, by increasing the temperature of the acid gas feed, the temperature of the main burner decreased. In general, the concentration of oxygen in the input air into the Claus unit had little effect on the temperature of the main burner (This is true for all parameters). The optimal catalytic bed temperature, tail gas ratio and type of catalytic bed were also determined and these conditions are a minimum temperature of 300°C, a ratio of 2.0 and a hydrolysing Claus bed.

关键词： Claus unit     concentration of H2S     tail gas ratio     sulfur recovery     catalytic bed    

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Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

《能源前沿（英文）》 2023年 第17卷 第4期   页码 516-526 doi: 10.1007/s11708-022-0844-6

摘要： A two-stage gas-coupled Stirling/pulse tube refrigerator (SPR), whose first and second stages respectively involve Stirling and pulse tube refrigeration cycles, is a very promising spaceborne refrigerator. The SPR has many advantages, such as a compact structure, high reliability, and high performance, and is expected to become an essential refrigerator for space applications. In research regarding gas-coupled regenerative refrigerator, the energy flow distribution between the two stages, and optimal phase difference between the pressure wave and volume flow, are two critical parameters that could widely influence refrigerator performance. The effects of displacer displacement on the pressure wave, phase difference, acoustic power distribution, and inter-stage cooling capacity shift of the SPR have been investigated experimentally. Notably, to obtain the maximum first-stage cooling capacity, an inflection point in displacement exists. When the displacer displacement is larger than the inflection point, the cooling capacity could be distributed between the first and second stages. In the present study, an SPR was designed and manufactured to work between the liquid hydrogen and liquid oxygen temperatures, which can be used to cool small-scale zero boil-off systems and space detectors. Under appropriate displacer displacement, the SPR can reach a no-load cooling temperature of 15.4 K and obtain 2.6 W cooling capacity at 70 K plus 0.1 W cooling capacity at 20 K with 160 W compressor input electric power.

关键词： Stirling/pulse tube refrigerator     displacer displacement     space application     phase shift     energy distribution    

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Predictive model to decouple the contributions of friction and plastic deformation to machined surface temperatures

Subhash ANURAG, Yuebin GUO,

《机械工程前沿（英文）》 2010年 第5卷 第3期   页码 247-255 doi: 10.1007/s11465-010-0097-7

摘要： Temperature on the machined surface is critical for surface integrity and the performance of a precision component. However, the temperature of a machined surface is challenging for in-situ measurement. Furthermore, the individual contribution of tool/work friction and plastic deformation of work materials to surface temperature is very difficult to quantify because the measured temperature is always the resultant temperature. This lack of understanding on the temperature distribution blocks the design of effective cutting tool geometries and materials to minimize surface temperature. This study provides a finite element method based on a predictive model to decouple the contributions of tool/work friction and material plastic deformation to surface temperature in a dry cutting process. The study shows that the plastic deformation of work material contributes to the majority of surface temperature, whereas the tool/work friction contribution is secondary. High temperatures are produced when more materials are plowed under the cutting edge. A large tool/work friction leads to higher surface temperatures, and the use of a cutting tool with physical properties in process simulation significantly improves the accuracy of predicted surface temperatures. Residual stress reversal from subsurface maximum residual to surface maximum residual stress may occur when tool/work friction increases.

关键词： surface temperature     friction     residual stress     finite element analysis (FEA)     dry cutting     tool property    

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Appraising the potential of calcium sulfoaluminate cement-based grouts in simulated permafrost environments

《结构与土木工程前沿（英文）》 2023年 第17卷 第5期   页码 722-731 doi: 10.1007/s11709-023-0950-5

摘要： The aim of this study is to appraise the potential of calcium sulfoaluminate (CSA) cement-based grouts in simulated permafrost environments. The hydration and performance of CSA cement-based grouts cured in cold environments (10, 0, and −10 °C) are investigated using a combination of tests, including temperature recording, X-ray diffraction (XRD) tests, thermogravimetric analysis (TGA), and unconfined compressive strength (UCS) tests. The recorded temperature shows a rapid increase in temperature at the early stage in all the samples. Meanwhile, results of the TGA and XRD tests show the generation of a significant quantity of hydration products, which indicates the rapid hydration of CSA cement-based grouts at the early stage at low temperatures. Consequently, the CSA cement-based grouts exhibit remarkably high early strength. The UCS values of the samples cured for 2 h at −10, 0, and 10 °C are 6.5, 12.0, and 12.3 MPa, respectively. The UCS of the grouts cured at −10, 0, and 10 °C increases continuously with age and ultimately reached 14.9, 19.0, and 30.6 MPa at 28 d, respectively. The findings show that the strength of grouts fabricated using CSA cement can develop rapidly in cold environments, thus rendering them promising for permafrost applications.

关键词： permafrost     low temperatures     calcium sulfoaluminate cement-based grouts     hydration reaction     compressive strength    

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An improved design method to predict the E-modulus and strength of FRP composites at different temperatures

Mohammed FARUQI, Gobishanker RAJASKANTHAN, Breanna BAILEY, Francisco AGUINIGA

《结构与土木工程前沿（英文）》 2022年 第16卷 第12期   页码 1653-1653 doi: 10.1007/s11709-019-0578-7

摘要： In recent years, there has been an increased interest in the use of fiber reinforced polymer (FRP) in the construction industry. However, the E-modulus and strength of such members at high service temperatures is still unknown. Modulus and strength of FRP at high service temperatures are highly required parameters for full design. The knowledge and application of this could lead to a cost effective and practical consideration in fire safety design. Thus, this paper proposes design methods for calculating the E-modulus and strength of FRP members at different temperatures. Experimental data from literature were normalized and compared with the results predicted by this method. It was found that the proposed design methods conservatively estimate the E-modulus and strength of FRP structural members. In addition, comparison was also made with direct references to the real behavior of materials. It was found to be satisfactory. Finally, an application is provided.

关键词： concrete     fiber reinforced polymer     E-modulus     strength     temperatures    

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Deflection behavior of a prestressed concrete beam reinforced with carbon fibers at elevated temperatures

Mohammed FARUQI, Mohammed Sheroz KHAN

《结构与土木工程前沿（英文）》 2019年 第13卷 第1期   页码 81-91 doi: 10.1007/s11709-018-0468-4

摘要： Fiber reinforced polymer(FRP) have unique advantages like high strength to weight ratio, excellent corrosion resistance, improving deformability and cost effectiveness. These advantages have gained wide acceptance in civil engineering applications. FRP tendons for prestressing applications are emerging as one of the most promising technologies in the civil engineering industry. However, the behavior of such members under the influence of elevated temperatures is still unknown. The knowledge and application of this could lead to a cost effective and practical considerations in fire safety design. Therefore, this study examines the deflection behavior of the carbon fiber reinforced polymer(CFRP) prestressed concrete beam at elevated temperatures. In this article, an analytical model is developed which integrates the temperature dependent changes of effective modulus of FRP in predicting the deflection behavior of CFRP prestressed concrete beams within the range of practical temperatures. This model is compared with a finite element mode (FEM) of a simply supported concrete beam prestressed with CFRP subjected to practical elevated temperatures. In addition, comparison is also made with an indirect reference to the real behavior of the material. The results of the model correlated reasonably with the finite element model and the real behavior. Finally, a practical application is provided.

关键词： FRP     CFRP     concrete     elevated temperatures     deflections     prestress    

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Comparative study of oscillating flow characteristics of cryocooler regenerator at low temperatures

Yonglin JU , Qingqing SHEN ,

《能源前沿（英文）》 2009年 第3卷 第1期   页码 80-84 doi: 10.1007/s11708-009-0008-y

摘要： A brief review is presented on previous experimental results and correlations on the friction factor of cryocooler regenerators operating at oscillating flow and pulsating pressure conditions, for different mesh sizes of packed woven screens, focusing on the effects of different operating frequencies ranging from 20 to 80 Hz, at room and cryogenic temperatures. A comparison of the friction factor data with those of other studies is presented to clarify the reason for the difference. Finally, a new oscillating flow correlation of regenerators, in terms of several non-dimensional parameters, is discussed and compared.

关键词： friction factor     regenerator     oscillating flow     high frequency    

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Characterization and performance of V

Caiting LI, Qun LI, Pei LU, Huafei CUI, Guangming ZENG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 156-161 doi: 10.1007/s11783-010-0295-x

摘要： A series of CeO supported V O catalysts with various loadings were prepared with different calcination temperatures by the incipient impregnation. The catalysts were evaluated for low temperature selective catalytic reduction (SCR) of NO with ammonia (NH ). The effects of O and SO on catalytic activity were also studied. The catalysts were characterized by specific surface areas (S ) and X–ray diffraction (XRD) methods. The experimental results showed that NO conversion changed significantly with the different V O loading and calcination temperature. With the V O loading increasing from 0 to 10 wt%, NO conversion increased significantly, but decreased at higher loading. The optimum calcination temperature was 400°C. The best catalyst yielded above 80% NO conversion in the reaction temperature range of 160°C–300°C. The formation of CeVO on the surface of catalysts caused the decrease of redox ability.

关键词： V2O5/CeO2 catalysts     NH3-SCR (selective catalytic reduction)     the incipient impregnation     low temperatures    

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中国铝工业应用新型电极材料的研究与展望

邱竹贤

《中国工程科学》 2001年 第3卷 第5期   页码 50-54

摘要：

介绍了现代铝工业上新近开发研制的几种电极材料，涉及惰性阴极、惰性阳极、双极性电极等；还研制了低温电解质，使电解温度降低到800～900℃。如果惰性电极与低温电解质配合起来应用，则能够明显减少工业铝生产中的物料消耗，节省电能，增大电解槽生产能力，并改善环境状况，可望大幅度降低生产成本。

关键词： 惰性阳极     惰性阴极     SiC绝缘侧壁     低温铝电解    

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Experimental study on behavior of mortar-aggregate interface after elevated temperatures

Wan WANG, Jianzhuang XIAO, Shiying XU, Chunhui WANG

《结构与土木工程前沿（英文）》 2017年 第11卷 第2期   页码 158-168 doi: 10.1007/s11709-016-0374-6

摘要： A push-out test program was designed and conducted to study the meso-scale behavior of mortar-aggregate interface for concrete after elevated temperatures ranging from 20°C to 600°C with the concept of modeled concrete (MC) and modeled recycled aggregate concrete (MRAC). The MCs and MRACs were designed with different strength grade of mortar and were exposed to different elevated temperatures. Following that the specimens were cooled to room temperature and push-out tests were conducted. Failure process and mechanical behaviors were analyzed based on failure modes, residual load-displacement curves, residual peak loads and peak displacements. It is found that failure modes significantly depended on specimen type, the elevated temperature and the strength grade of mortar. For MC, major cracks started to propagate along the initial cracks caused by elevated temperatures at about 80% of residual peak load. For MRAC, the cracks appeared at a lower level of load with the increasing elevated temperatures. The cracks connected with each other, formed a failure face and the specimens were split into several parts suddenly when reaching the residual peak load. Residual load-displacement curves of different specimens had similarities in shape. Besides, effect of temperatures and strength grade of mortar on residual peak load and peak displacement were analyzed. For MC and MRAC with higher strength of new hardened mortar, the residual peak load kept constant when the temperature is lower than 400°C and dropped by 43.5% on average at 600°C. For MRAC with lower strength of new hardened mortar, the residual peak load began to reduce when the temperatures exceeded 200°C and reduced by 27.4% and 60.8% respectively at 400°C and 600°C. The properties of recycled aggregate concrete (RAC) may be more sensitive to elevated temperatures than those of natural aggregate concrete (NAC) due to the fact that the interfacial properties of RAC are lower than those of NAC, and are deteriorated at lower temperatures.

关键词： mortar-aggregate interface     push-out test     elevated temperatures     modeled concrete (MC)     modeled recycled aggregate concrete (MRAC)    

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Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo, Osun State, Nigeria

O. S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

《能源前沿（英文）》 2013年 第7卷 第2期   页码 214-222 doi: 10.1007/s11708-013-0241-2

摘要： In this study, the global solar radiation on horizontal surface in Osogbo, Osun state, Nigeria was analyzed using 11-year data (1997–2007). Correlations using linear and quadratic expressions were developed to relate the global solar radiation on horizontal surface based on relative sunshine hours and temperature measurements for evaluating the monthly average daily global solar radiation. The calculated monthly clearness index values indicate that the prevailing weather condition in Osogbo is heavily overcast. All the developed quadratic correlations gave better correlation coefficients (0.834, 0.872 and 0.823 respectively) than the linear models. However, the Hargreaves and Samani related based quadratic model gave the best among the three developed quadratic expressions and is therefore suggested for estimating the monthly global radiation in this site and its surroundings.

关键词： global solar radiation     Hargreaves model     sunshine hour     ambient temperatures     Osogbo    

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具有聚集诱导发光活性的抗冻水凝胶用于低温环境下多级信息的加密和解密 Article

睢晓洁, 汪晓东, 蔡诚诚, 马君怡, 杨静, 张雷

《工程（英文）》 2023年 第23卷 第4期   页码 82-89 doi: 10.1016/j.eng.2022.03.021

摘要：

抗冻水凝胶可以在零下温度环境中调节内部水分子的冻结行为，从而保持其优异特性（如智能响应性和液体运输）以及拓展其在寒冷条件下的应用。本文开发了一系列具有聚集诱导发光（AIE）活性的抗冻水凝胶，可实现在零下温度的信息加密和解密。通过改变水凝胶内的甜菜碱含量，该水凝胶可呈现出不同的冻结温度（Tf）。当温度高于/低于Tf时，编码于水凝胶内的AIE荧光分子不发射/发射荧光，从而可以实现信息的加密和解密。此外，通过调控水凝胶的冻结程序或者在水凝胶内原位引入具有光热效应的硫化铜纳米颗粒并结合特定的照射条件，可以实现信息的多级加密和解密，从而增强信息的安全性。最后，由于解密的信息图案对温度波动具有不可逆性，因此该具有AIE活性的抗冻水凝胶可作为无需外界供能的防伪标签，用于实时和可视化监测冷冻运输（−80 ℃）过程中生物样本（如间充质干细胞和红细胞）的活性。

关键词： 抗冻水凝胶     聚集诱导发光     加密     解密     防伪    

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700 °C 及以上蒸汽温度下先进USC发电厂用耐热材料的研究和开发 Review

Fujio Abe

《工程（英文）》 2015年 第1卷 第2期   页码 211-224 doi: 10.15302/J-ENG-2015031

摘要：

欧洲、美国、日本已开展蒸汽温度为700 °C 及以上的先进超超临界(A-USC) 发电厂用材料开发项目，以实现更高能效和低二氧化碳排放量。近年来中国、印度等也开展了上述项目的开发和研究。这些项目涉及采用镍基合金更换马氏体9%~12%Cr 钢以用于最高温度的锅炉和涡轮部件，从而在700 °C 及以上温度下提供充足的蠕变强度。为尽量减少对昂贵的镍基合金的需求，马氏体9%~12%Cr 钢可用于A-USC 电厂中的次高温部件(最高温度不超过650 °C)。本文综述了A-USC 电厂厚型材锅炉和涡轮部件用镍基合金和马氏体9%~12%Cr 钢的研究和开发，主要关注高温下基底金属和焊缝的长期蠕变断裂强度、焊缝强度损失、蠕变疲劳性质和显微结构演化。

关键词： 镍基合金     9 %~12 % Cr 钢     蠕变强度     蠕变疲劳性质     焊缝     晶界     显微结构     &gamma     &prime     M23C6 碳化物    

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标题 作者 时间 类型 操作

An investigation of reaction furnace temperatures and sulfur recovery

S. ASADI, M. PAKIZEH, M. POURAFSHARI CHENAR

期刊论文

Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

期刊论文

Predictive model to decouple the contributions of friction and plastic deformation to machined surface temperatures

Subhash ANURAG, Yuebin GUO,

期刊论文

Appraising the potential of calcium sulfoaluminate cement-based grouts in simulated permafrost environments

期刊论文

An improved design method to predict the E-modulus and strength of FRP composites at different temperatures

Mohammed FARUQI, Gobishanker RAJASKANTHAN, Breanna BAILEY, Francisco AGUINIGA

期刊论文

Deflection behavior of a prestressed concrete beam reinforced with carbon fibers at elevated temperatures

Mohammed FARUQI, Mohammed Sheroz KHAN

期刊论文

Comparative study of oscillating flow characteristics of cryocooler regenerator at low temperatures

Yonglin JU , Qingqing SHEN ,

期刊论文

Characterization and performance of V

Caiting LI, Qun LI, Pei LU, Huafei CUI, Guangming ZENG

期刊论文

中国铝工业应用新型电极材料的研究与展望

邱竹贤

期刊论文

Experimental study on behavior of mortar-aggregate interface after elevated temperatures

Wan WANG, Jianzhuang XIAO, Shiying XU, Chunhui WANG

期刊论文

Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo, Osun State, Nigeria

O. S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

期刊论文

具有聚集诱导发光活性的抗冻水凝胶用于低温环境下多级信息的加密和解密

睢晓洁, 汪晓东, 蔡诚诚, 马君怡, 杨静, 张雷

期刊论文

700 °C 及以上蒸汽温度下先进USC发电厂用耐热材料的研究和开发

Fujio Abe

期刊论文