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Thermal radiative properties of metamaterials and other nanostructured materials: A review

Ceji FU, Zhuomin M. ZHANG

《能源前沿(英文)》 2009年 第3卷 第1期   页码 11-26 doi: 10.1007/s11708-009-0009-x

摘要: The ability to manufacture, control, and manipulate structures at extremely small scales is the hallmark of modern technologies, including microelectronics, MEMS/NEMS, and nano-biotechnology. Along with the advancement of microfabrication technology, more and more investigations have been performed in recent years to understand the influence of microstructures on radiative properties. The key to the enhancement of performance is through the modification of the reflection and transmission properties of electromagnetic waves and thermal emission spectra using one-, two-, or three-dimensional micro/nanostructures. This review focuses on recent developments in metamaterials–manmade materials with exotic optical properties, and other nanostructured materials, such as gratings and photonic crystals, for application in radiative energy transfer and energy conversion systems.

关键词: metamaterial     nanostructured material     thermal radiative property     radiative energy transfer    

Radiative properties of materials with surface scattering or volume scattering: A review

Qunzhi ZHU, Hyunjin LEE, Zhuomin M. HANG

《能源前沿(英文)》 2009年 第3卷 第1期   页码 60-79 doi: 10.1007/s11708-009-0011-3

摘要: Radiative properties of rough surfaces, particulate media and porous materials are important in thermal engineerit transfer between surfaces and volume elements in participating media, as well as for accurate radiometric temperature measurements. In this paper, recent research on scattering of thermal radiation by rough surfaces, fibrous insulation, soot, aerogel, biological materials, and polytetrafluoroethylene (PTFE) was reviewed. Both theoretical modeling and experimental investigation are discussed. Rigorous solutions and approximation methods for surface scattering and volume scattering are described. The approach of using measured surface roughness statistics in Monte Carlo simulations to predict radiative properties of rough surfaces is emphasized. The effects of various parameters on the radiative properties of particulate media and porous materials are summarized.

关键词: aerogel     fiber     particle scattering     radiative properties     soot     surface roughness    

A spectrally selective surface structure for combined photothermic conversion and radiative sky cooling

Bin ZHAO, Xianze AO, Nuo CHEN, Qingdong XUAN, Mingke HU, Gang PEI

《能源前沿(英文)》 2020年 第14卷 第4期   页码 882-888 doi: 10.1007/s11708-020-0694-z

摘要: The sun and outer space are the ultimate heat and cold sources for the earth, respectively. They have significant potential for renewable energy harvesting. In this paper, a spectrally selective surface structure that has a planar polydimethylsiloxane layer covering a solar absorber is conceptually proposed and optically designed for the combination of photothermic conversion (PT) and nighttime radiative sky cooling (RC). An optical simulation is conducted whose result shows that the designed surface structure (i.e., PT-RC surface structure) has a strong solar absorption coefficient of 0.92 and simultaneously emits as a mid-infrared spectral-selective emitter with an average emissivity of 0.84 within the atmospheric window. A thermal analysis prediction reveals that the designed PT-RC surface structure can be heated to 79.1°C higher than the ambient temperature in the daytime and passively cooled below the ambient temperature of approximately 10°C in the nighttime, indicating that the designed PT-RC surface structure has the potential for integrated PT conversion and nighttime RC utilization.

关键词: solar energy     photothermic conversion     radiative sky cooling     spectral selectivity     multilayer film    

Entropy flow, entropy generation, exergy flux, and optimal absorbing temperature in radiative transfer

Zeshao CHEN, Songping MO, Peng HU, Shouli JIANG, Gang WANG, Xiaofang CHENG,

《能源前沿(英文)》 2010年 第4卷 第3期   页码 301-305 doi: 10.1007/s11708-010-0006-0

摘要: Taking nonequilibrium radiative heat transfer between two surfaces as an example, the nonequilibrium thermodynamics of radiation is studied and discussed. The formulas of entropy flow, entropy generation, exergy flux, and optimal temperature of absorbing surface for maximum exergy output are derived. The result is a contribution to the thermodynamic analysis and optimization of solar energy utilization and can be applied in more complex radiative heat transfer cases.

关键词: radiative heat transfer     entropy generation     exergy     thermodynamics    

Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

《环境科学与工程前沿(英文)》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0840-3

摘要: We modeled the impact of haze radiative effects on precipitation in North China. Shortwave heating induced by haze radiative effects would reduce heavy rainfalls. Convection was the key factor that whether precipitation was enhanced or suppressed. Precipitation was often suppressed where CAPE, RH and updraft velocities were high. The impact of haze radiative effect on summertime 24-h convective precipitation over North China was investigated using WRF model (version 3.3) through model sensitivity studies between scenarios with and without aerosol radiative effects. The haze radiative effect was represented by incorporating an idealized aerosol optical profile, with AOD values around 1, derived from the aircraft measurement into the WRF shortwave scheme. We found that the shortwave heating induced by aerosol radiative effects would significantly reduce heavy rainfalls, although its effect on the post-frontal localized thunderstorm precipitation was more diverse. To capture the key factors that determine whether precipitation is enhanced or suppressed, model grids with 24-h precipitation difference between the two scenarios exceeding certain threshold (>30 mm or<-30 mm) were separated into two sets. Analyses of key meteorological variables between the enhanced and suppressed regimes suggested that atmospheric convection was the most important factor that determined whether precipitation was enhanced or suppressed during summertime over North China. The convection was stronger over places with precipitation enhancement over 30 mm. Haze weakened the convection over places with precipitation suppression exceeding 30 mm and caused less water vapor to rise to a higher level and thus further suppressed precipitation. The suppression of precipitation was often accompanied with relatively high convective available potential energy (CAPE), relative humidity (RH) and updraft velocities.

关键词: Haze     Aerosol radiative effects     Convective precipitation    

Near-field radiative thermoelectric energy converters: a review

Eric TERVO, Elham BAGHERISERESHKI, Zhuomin ZHANG

《能源前沿(英文)》 2018年 第12卷 第1期   页码 5-21 doi: 10.1007/s11708-017-0517-z

摘要: Radiative thermoelectric energy converters, which include thermophotovoltaic cells, thermoradiative cells, electroluminescent refrigerators, and negative electroluminescent refrigerators, are semiconductor p-n devices that either generate electricity or extract heat from a cold body while exchanging thermal radiation with their surroundings. If this exchange occurs at micro or nanoscale distances, power densities can be greatly enhanced and near-field radiation effects may improve performance. This review covers the fundamentals of near-field thermal radiation, photon entropy, and nonequilibrium effects in semiconductor diodes that underpin device operation. The development and state of the art of these near-field converters are discussed in detail, and remaining challenges and opportunities for progress are identified.

关键词: energy conversion systems     luminescent refrigeration     near-field radiation     thermophotovoltaic     thermoradiative cell    

Challenge of global climate change: Prospects for a new energy paradigm

Michael B. MCELROY

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 2-11 doi: 10.1007/s11783-010-0005-8

摘要: Perspectives on the challenge posed by potential future climate change are presented including a discussion of prospects for carbon capture followed either by sequestration or reuse including opportunities for alternatives to the use of oil in the transportation sector. The potential for wind energy as an alternative to fossil fuel energy as a source of electricity is outlined including the related opportunities for cost effective curtailment of future growth in emissions of CO.

关键词: climate change     carbon capture     wind     ethanol     CO2     radiative forcing    

基于蝶翅三级微纳米结构的定制光子工程辐射制冷纺织品 Article

郭竑宇, 牛田野, 俞建勇, 王学利, 斯阳

《工程(英文)》 2023年 第31卷 第12期   页码 120-126 doi: 10.1016/j.eng.2023.07.019

摘要:

通过将被动辐射制冷策略与个人热管理技术相结合,为缓解人体在户外活动中的热不适感提供了新的思路。然而,目前大多数被动辐射制冷材料在穿着舒适性和耐用性方面存在不足。本文采用微阵列技术,成功制备出了具有辐射制冷能力的定制光子工程可穿戴纺织品。所开发的辐射制冷纺织品(RCTs)具有一定的透气透湿性、结构稳定性和扩展光谱响应性(太阳光反射率91.7%、大气窗口发射率95.8%)。在正午炎热环境的室外降温测试中,RCTs所覆盖的皮肤模拟器温度比棉织物低4.4 ℃。这种仿生结构的开发为可穿戴、热湿舒适和结构稳定的辐射制冷纺织品在个人热管理领域的应用提供了新的见解。

关键词: 仿生材料     个人热管理     纺织品     辐射制冷    

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

《结构与土木工程前沿(英文)》 2021年 第15卷 第6期   页码 1390-1399 doi: 10.1007/s11709-021-0775-z

摘要: High viscosity asphalt (HVA) has been a great success as a drainage pavement material. However, the larger porosity of drainage asphalt mixtures weakens the cohesion and adhesion and leads to premature rutting, water damage, spalling and cracking. The purpose of this study was to investigate the rheological properties of HVA prepared using different high viscosity modifiers through conventional tests, Brookfield viscosity tests, dynamic shear rheometer tests and bending beam rheometer tests. The conventional performance results demonstrated SBS + rubber asphalt (SRA-1/2) exhibited excellent elastic recovery and low-temperature flexibility. The 60°C dynamic viscosity results indicated TPS + rubber asphalt (TRA) had the excellent adhesion. The rotational viscosity results and rheological results indicated that SRA-2 not only exhibited excellent temperature stability and workability, as well as excellent resistance to deformation and rutting resistance, but also exhibited excellent low-temperature cracking resistance and relaxation performance. Based on rheological results, the PG classification of HVA was 16% rubber + asphalt for PG76-22, 20% rubber + asphalt for PG88-22, TRA and SRA-1/2 for PG88-28. From comprehensive evaluation of the viscosity, temperature stability and sensitivity, as well as high/low temperature performance of HVA, SRA-2 was found to be more suited to the requirements of drainage asphalt pavement materials.

关键词: high viscosity asphalt     rheological properties     rubber     modifier     viscosity    

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

《农业科学与工程前沿(英文)》 2021年 第8卷 第4期   页码 545-558 doi: 10.15302/J-FASE -2020349

摘要:

Agriculture uses a large proportion of global and regional water resources. Due to the rapid increase of population in the world, the increasing competition for water resources has led to an urgent need in increasing crop water productivity for agricultural sustainability. As the medium for crop growth, soils and their properties are important in affecting crop water productivity. This review examines the effects of soil physical, chemical, and microbial properties on crop water productivity and the quantitative relationships between them. A comprehensive view of these relationships may provide important insights for soil and water management in arable land for agriculture in the future.

 

关键词: crop water productivity     crop yield     soil chemical properties     soil microbial properties     soil physical properties     water consumption    

Effect of earth reinforcement, soil properties and wall properties on bridge MSE walls

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1209-1221 doi: 10.1007/s11709-021-0764-2

摘要: Mechanically stabilized earth (MSE) retaining walls are popular for highway bridge structures. They have precast concrete panels attached to earth reinforcement. The panels are designed to have some lateral movement. However, in some cases, excessive movement and even complete dislocation of the panels have been observed. In this study, 3-D numerical modeling involving an existing MSE wall was undertaken to investigate various wall parameters. The effects of pore pressure, soil cohesion, earth reinforcement type and length, breakage/slippage of reinforcement and concrete strength, were examined. Results showed that the wall movement is affected by soil pore pressure and reinforcement integrity and length, and unaffected by concrete strength. Soil cohesion has a minor effect, while the movement increased by 13–20 mm for flexible geogrid reinforced walls compared with the steel grid walls. The steel grid stresses were below yielding, while the geogrid experienced significant stresses without rupture. Geogrid reinforcement may be used taking account of slippage resistance and wall movement. If steel grid is used, non-cohesive soil is recommended to minimize corrosion. Proper soil drainage is important for control of pore pressure.

关键词: mechanically stabilized earth walls     precast concrete panels     backfill soil     finite element modeling     earth reinforcement    

Mechanical properties and microstructure of multilayer graphene oxide cement mortar

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 1058-1070 doi: 10.1007/s11709-021-0747-3

摘要: This study reports on the effects of multilayer graphene oxide (MGO) on compressive strength, flexural strength, and microstructure of cement mortar. The cement mortar was prepared with type P. II. 52.5 Portland cement, standard sand, and MGO. Four mixes were prepared with inclusion of MGO (0%, 0.02%, 0.04%, and 0.06% by weight of cement). The testing result shows that the compressive of GO-cement mortar increased by 4.84%–13.42%, and the flexural strength increased by 4.37%–8.28% at 3 d. GO-cement mortar’s compressive strength and flexural strength at 7 d increased by 3.84%–12.08% and 2.54%–13.43%, respectively. MGO made little contribution to the increases of compressive strength and flexural strength of cement mortar at 28 d. The results of X-ray diffraction (XRD), scanning electron microscope (SEM), and nitrogen (N2) adsorption/desorption tests show that the types of hydration products and crystal grain size did not change after adding MGO. Still, it can help to improve the microstructure of the cement mortar via regulating hydration products and can provide more condensed cores to accelerate hydration. Furthermore, the regulating action of MGO for the microstructure of cement mortar at an early age was better than that at 28 d.

关键词: graphene oxide     cement     mortar     mechanical properties     microstructure    

Synthesis, characterization and assessment thermal properties of clay based nanopigments

Mohammad Banimahd KIEVANI, Milad EDRAKI

《化学科学与工程前沿(英文)》 2015年 第9卷 第1期   页码 40-45 doi: 10.1007/s11705-015-1505-7

摘要: Nano-clay based pigments (NCP) are new type of pigments composed of organic dyes and layered silicate-clay nano-particles, and have already been used in polymeric coatings to improve mechanical thermal and stability properties. In this paper, the basic blue 41(BB41) was intercalated into Na - montmorillonite in an aqueous medium. The dye-intercalated montmorillonite was centrifuged, dried, and milled to prepare the nanopigment particles. X-ray diffraction showed an increase in the basal spacing, thus confirming intercalation of the BB41 molecules within the nanostructures of the interlayer spaces. Fourier transform infrared spectroscopy was used for identifying the functional groups and chemical bounding of Na -montmorillonite, BB41 and montmorillonite-BB41. The morphology of NCP was also studied by transmission electron microscopy. Finally, thermo-gravimetric analysis and differential thermograms suggested the thermal stability of the intercalated dye was improved.

关键词: nanopigment     layered silicate     cationic dye     thermal properties    

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based onrheological properties and micro-characterization

《结构与土木工程前沿(英文)》 2023年 第17卷 第4期   页码 625-636 doi: 10.1007/s11709-023-0938-1

摘要: The research and development of high-performance pavement materials has been intensified owing to the demand for long-life pavements. This study is performed to develop a novel pavement material using waste rubber powder, waste lubricating by-product (LBP), and asphalt. Subsequently, the aging properties and aging mechanism of activated waste rubber powder modified asphalt (ARMA) are investigated based on its rheological properties and micro-characterization. The rheological results show that, compared with waste rubber powder modified asphalt (RMA), ARMA offers a higher aging resistance and a longer fatigue life. A comparison and analysis of the rheological aging parameters of ARMA and RMA show that LBP activation diminishes the aging sensitivity of ARMA. The micro-characterization result shows that the aging of ARMA may be caused by the fact that LBP-activated waste rubber powder is more reactive and can form a dense colloidal structure with asphalt. Therefore, the evaporation loss of asphalt light components by heat and the damage to the colloidal structure by oxygen during the aging process are impeded, and the thermal-oxidative aging resistance of ARMA is improved.

关键词: rubber powder modified asphalt     aging     mechanism     rheological     characterization    

Biological properties and clinical applications of berberine

Danyang Song, Jianyu Hao, Daiming Fan

《医学前沿(英文)》 2020年 第14卷 第5期   页码 564-582 doi: 10.1007/s11684-019-0724-6

摘要: Berberine, an isoquinoline alkaloid isolated from the Chinese herb and other plants, has a wide range of pharmacological properties. Berberine can be used to treat many diseases, such as cancer and digestive, metabolic, cardiovascular, and neurological diseases. Berberine has protective capacities in digestive diseases. It can inhibit toxins and bacteria, including , protect the intestinal epithelial barrier from injury, and ameliorate liver injury. Berberine also inhibits the proliferation of various types of cancer cells and impedes invasion and metastasis. Recent evidence has confirmed that berberine improves the efficacy and safety of chemoradiotherapies. In addition, berberine regulates glycometabolism and lipid metabolism, improves energy expenditure, reduces body weight, and alleviates nonalcoholic fatty liver disease. Berberine also improves cardiovascular hemodynamics, suppresses ischemic arrhythmias, attenuates the development of atherosclerosis, and reduces hypertension. Berberine shows potent neuroprotective effects, including antioxidative, antiapoptotic, and anti-ischemic. Furthermore, berberine exerts protective effects against other diseases. The mechanisms of its functions have been extensively explored, but much remains to be clarified. This article summarizes the main pharmacological actions of berberine and its mechanisms in cancer and digestive, metabolic, cardiovascular, and neurological diseases.

关键词: berberine     Coptis chinensis     pharmacological properties     mechanism     clinical applications    

标题 作者 时间 类型 操作

Thermal radiative properties of metamaterials and other nanostructured materials: A review

Ceji FU, Zhuomin M. ZHANG

期刊论文

Radiative properties of materials with surface scattering or volume scattering: A review

Qunzhi ZHU, Hyunjin LEE, Zhuomin M. HANG

期刊论文

A spectrally selective surface structure for combined photothermic conversion and radiative sky cooling

Bin ZHAO, Xianze AO, Nuo CHEN, Qingdong XUAN, Mingke HU, Gang PEI

期刊论文

Entropy flow, entropy generation, exergy flux, and optimal absorbing temperature in radiative transfer

Zeshao CHEN, Songping MO, Peng HU, Shouli JIANG, Gang WANG, Xiaofang CHENG,

期刊论文

Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

期刊论文

Near-field radiative thermoelectric energy converters: a review

Eric TERVO, Elham BAGHERISERESHKI, Zhuomin ZHANG

期刊论文

Challenge of global climate change: Prospects for a new energy paradigm

Michael B. MCELROY

期刊论文

基于蝶翅三级微纳米结构的定制光子工程辐射制冷纺织品

郭竑宇, 牛田野, 俞建勇, 王学利, 斯阳

期刊论文

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

期刊论文

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

期刊论文

Effect of earth reinforcement, soil properties and wall properties on bridge MSE walls

期刊论文

Mechanical properties and microstructure of multilayer graphene oxide cement mortar

期刊论文

Synthesis, characterization and assessment thermal properties of clay based nanopigments

Mohammad Banimahd KIEVANI, Milad EDRAKI

期刊论文

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based onrheological properties and micro-characterization

期刊论文

Biological properties and clinical applications of berberine

Danyang Song, Jianyu Hao, Daiming Fan

期刊论文