资源类型

期刊论文 67

年份

2023 9

2022 5

2021 8

2020 2

2019 2

2018 4

2017 5

2016 5

2015 4

2014 5

2013 2

2011 3

2010 2

2009 3

2008 1

2007 4

2001 1

展开 ︾

关键词

6016 合金 1

DPP);分布式功率转换器;开关电容转换器 1

IgG 1

LED灯具;加速老化测试;中位寿命;滑动平均误差 1

MPPT);差分功率处理(Differential power processing 1

N-糖基心血管年龄 1

RGB-D 1

仪表板材料 1

传感器融合 1

保险杠材料 1

光泽 1

光老化性能 1

免疫球蛋白G 1

全局边界搜索 1

冗余策略 1

加速湿热老化 1

四元数傅里叶变换;四元数线性正则变换;采样定理;部分和总体四元数希尔伯特变换;部分和总体广义四元数希尔伯特变换;截断误差 1

固溶处理 1

圆柱 1

展开 ︾

检索范围:

排序: 展示方式:

the characterization of pore structures and permeability of diesel contaminated clays under different aging

《结构与土木工程前沿(英文)》   页码 1264-1280 doi: 10.1007/s11709-023-0921-x

摘要: In this study, mercury intrusion porosimetry (MIP) and X-ray micro-computed tomography (XRμCT) were used to characterize the pore structures and investigate the permeability characteristics of clay after aging and contamination with diesel. The results of the MIP tests showed that aging leads to reductions in porosity and average diameter, as well as an increase in tortuosity. The XRμCT analysis yielded consistent results; it showed that aging renders pores more spherical and isotropic and pore surfaces smoother. This weakens the pore connectivity. Micromorphological analysis revealed that aging led to the rearrangement of soil particles, tighter interparticle overlapping, and a reduction in pore space. The combination of MIP and XRμCT provided a comprehensive and reliable characterization of the soil pore structure. An increased diesel content increased the porosity and average diameter and reduced the tortuosity of the pores. Mechanistic analysis showed that aging weakens interparticle cohesion; this causes large agglomerates to break down into smaller agglomerates, resulting in a tighter arrangement and a subsequent reduction in porosity. An increase in diesel content increases the number of large agglomerates and pore spaces between agglomerates, resulting in increased porosity. Both aging and diesel content can weaken the permeation characteristics of soil.

关键词: MIP     XRμCT     aging     diesel content     pore structure     permeability characteristics    

Mechanism and characterization of microplastic aging process: A review

《环境科学与工程前沿(英文)》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1700-6

摘要:

● Methods for estimating the aging of environmental micro-plastics were highlighted.

关键词: Microplastics     Aging     Degradation     Characterization     Mechanism    

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based on

《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    

Insights into influence of aging processes on zero-valent iron modified biochar in copper(II) immobilization

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 880-892 doi: 10.1007/s11705-022-2282-8

摘要: The zero-valent iron modified biochar materials are widely employed for heavy metals immobilization. However, these materials would be inevitably aged by natural forces after entering into the environment, while there are seldom studies reported the aging effects of zero-valent iron modified biochar. In this work, the hydrogen peroxide and hydrochloric acid solution were applied to simulate aging conditions of zero-valent iron modified biochar. According to the results, the adsorption capacity of copper(II) contaminants on biochar, zero-valent iron modified biochar-1, and zero-valent iron modified biochar-2 after aging was decreased by 15.36%, 22.65% and 23.26%, respectively. The surface interactions were assigned with chemisorption occurred on multi-molecular layers, which were proved by the pseudo-second-order and Langmuir models. After aging, the decreasing of capacity could be mainly attributed to the inhibition of ion-exchange and zero-valent iron oxidation. Moreover, the plant growth and soil leaching experiments also proved the effects of aging treatment, the zero-valent iron modified biochar reduced the inhibition of copper(II) bioavailability and increased the mobility of copper(II) after aging. All these results bridged the gaps between bio-adsorbents customization and their environmental behaviors during practical agro-industrial application.

关键词: zero-valent iron modified biochar     aging processes     copper removal     adsorption     pilot-scale experiments    

Projections of heat-related excess mortality in China due to climate change, population and aging

《环境科学与工程前沿(英文)》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1732-y

摘要:

● Four scenarios were used to project heat-related excess mortality in China.

关键词: Heat-related excess mortality     LMDI     Aging     YLL     VSLY    

Methanation and chemolitrophic nitrogen removal by an anaerobic membrane bioreactor coupled partial nitrification

《环境科学与工程前沿(英文)》 2023年 第17卷 第6期 doi: 10.1007/s11783-023-1668-2

摘要:

● Efficient carbon methanation and nitrogen removal was achieved in AnMBR-PN/A system.

关键词: Anaerobic membrane bioreactor     Partial nitrification/Anammox     Carbon separation     Chemolitrophic nitrogen removal    

Partial pressures” of humid air in wide pressure and temperature ranges

Zidong WANG, Hanping CHEN, Shilie WENG

《能源前沿(英文)》 2013年 第7卷 第4期   页码 511-517 doi: 10.1007/s11708-013-0281-7

摘要: “Partial pressure” in humid air is a question very much concerned by scientists and no satisfactory answer has been found to date. This paper proposes a novel method to obtain the “partial pressures” of the water vapor and dry air in humid air. The results obtained by the proposed method are quite different from that obtained by Dalton’s partial pressure law. The fundamental behaviors of water vapor and dry air are studied in depth in wide pressure and temperature ranges. Semi-permeable membrane models are proposed and applied for both saturated and unsaturated humid air. “Improvement factors” are developed to quantitatively describe the magnitude of the interaction between dissimilar molecules. One discovery is that the “partial pressure” of the water vapor in saturated humid air equals , rather than ( · ) which was formerly believed. The other is that the interaction between dissimilar molecules may be omitted when temperature is above “cutting-off temperature” for unsaturated humid air. This paper satisfactorily answers the quest of “partial pressures” in humid air from a new perspective.

关键词: partial pressure     Dalton’s partial pressure law     humid air     saturated     unsaturated    

Outdoor aging of road asphalt and SBS modified asphalt

Li XIANG, Juan TU, Jian CHENG, Guohe QUE

《化学科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 35-42 doi: 10.1007/s11705-010-0551-4

摘要: The process of performance degradation of road asphalt (RA) is regarded as aging. At present, better understanding of the thermal-oxidative aging of asphalt is achieved and the corresponding method to evaluate this process is developed; meanwhile, photo-oxidative aging (aging in an atmospheric environment, which is referred to as “outdoor aging” in this paper) of asphalt remains at the initial stages of scientific exploration. The outdoor natural ultraviolet (UV) aging of RA and SBS modified asphalt (SBSMA) are investigated in this study. The experimental results show that the basic performances of RA and SBSMA present similar change tendencies. The softening point increased, while the penetration and ductility decreased as the outdoor aging time passed by, and the 5°C ductility (ductility measured at 5°C) of SBSMA decreased very quickly. The group components of RA and SBSMA also change during UV aging. The content of asphaltene rose and that of aromatics and saturates decreased, while the content of resins changed insignificantly. Moreover, the Fourier transform infrared (FTIR) graphs show that the content of sulfoxide and carbonyl groups in RA and SBSMA increased significantly during the outdoor aging process.

关键词: asphalt     SBS     modified road asphalt     outdoor aging     ultraviolet    

Role of brown adipose tissue in metabolic syndrome, aging, and cancer cachexia

null

《医学前沿(英文)》 2018年 第12卷 第2期   页码 130-138 doi: 10.1007/s11684-017-0555-2

摘要:

Brown adipose tissue (BAT) plays a fundamental role in maintaining body temperature by producing heat. BAT that had been know to exist only in mammals and the human neonate has received great attention for the treatment of obesity and diabetes due to its important function in energy metabolism, ever since it is recently reported that human adults have functional BAT. In addition, beige adipocytes, brown adipocytes in white adipose tissue (WAT), have also been shown to take part in whole body metabolism. Multiple lines of evidence demonstrated that transplantation or activation of BAT or/and beige adipocytes reversed obesity and improved insulin sensitivity. Furthermore, many genes involved in BAT activation and/or the recruitment of beige cells have been found, thereby providing new promising strategies for future clinical application of BAT activation to treat obesity and metabolic diseases. This review focuses on recent advances of BAT function in the metabolic aspect and the relationship between BAT and cancer cachexia, a pathological process accompanied with decreased body weight and increased energy expenditure in cancer patients. The underlying possible mechanisms to reduce BAT mass and its activity in the elderly are also discussed.

关键词: brown adipose tissue     beige adipocyte     anti-obesity     anti-diabetes     cancer cachexia     aging    

Effect of styrene-butadiene-styrene copolymer on the aging resistance of asphalt: An atomistic understanding

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1261-1276 doi: 10.1007/s11709-021-0761-5

摘要: To reveal the potential influence of styrene-butadiene-styrene (SBS) polymer modification on the anti-aging performance of asphalt, and its mechanism, we explored the aging characteristics of base asphalt and SBS-modified asphalt by reaction force field (ReaxFF) and classical molecular dynamics simulations. The results illustrate that the SBS asphalt is more susceptible to oxidative aging than the base asphalt under oxygen-deficient conditions due to the presence of unsaturated C=C bonds in the SBS polymer. In the case of sufficient oxygen, the SBS polymer inhibits the oxidation of asphalt by restraining the diffusion of asphalt molecules. Compared with the base asphalt, the SBS asphalt exhibits a higher degree of oxidation at the early stage of pavement service and a lower degree of oxidation in the long run. In addition, SBS polymer degrades into small blocks during aging, thus counteracting the hardening of aged asphalt and partially restoring its low-temperature cracking resistance.

关键词: SBS asphalt     oxidative aging     asphalt hardening     ReaxFF     molecular dynamics    

Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

《结构与土木工程前沿(英文)》 2021年 第15卷 第6期   页码 1480-1493 doi: 10.1007/s11709-021-0776-y

摘要: In waterfront geotechnical engineering, seismic and drainage conditions must be considered in the design of retaining structures. This paper proposes a general analytical method to evaluate the seismic active earth pressure on a retaining wall with backfill subjected to partial steady seepage flow under seismic conditions. The method comprises the following steps: i) determination of the total head, ii) upper bound solution of seismic active earth thrust, and iii) deduction for the earth pressure distribution. The determination of total head h(x,z) relies on the Fourier series expansions, and the expressions of the seismic active earth thrust and pressure are derived by using the upper bound theorem. Parametric studies reveal that insufficient drainage and earthquakes are crucial factors that cause unfavorable earth pressure. The numerical results confirm the validity of the total head distribution. Comparisons indicate that the proposed method is consistent with other relevant existing methods in terms of predicting seismic active earth pressure. The method can be applied to the seismic design of waterfront retaining walls.

关键词: seismic active earth pressure     partial seepage flow     pore pressure     anisotropy     upper bound theorem    

Methane partial oxidation over NiO-MgO/Ce

Piyawat PUE-ON, Vissanu MEEYOO, Thirasak RIRKSOMBOOON

《化学科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 289-296 doi: 10.1007/s11705-013-1345-2

摘要: Methane partial oxidation (MPO) is considered as an alternative method to produce hydrogen because it is an exothermic reaction to afford a suitable H /CO ratio of 2. However, carbon deposition on a catalyst is observed as a major cause of catalyst deactivation in MPO. In order to find suitable catalysts that prevent the carbon deposition, NiO-MgO/Ce Zr O (CZO) supported catalysts were prepared via the co-impregnation (C) and sequential incipient wetness impregnation (S) methods. The amount of Ni loading was fixed at 15 wt-% whereas the amount of MgO loading was varied from 5 to 15 wt-%. The results revealed that the addition of MgO shifted the light-off temperatures to higher temperatures. This is because the Ni surface was partially covered with MgO, and the strong interaction between NiO and NiMgO over CZO support led to the difficulty in reducing NiO to active Ni and thus less catalytic activity. However, among the catalysts tested, the 15Ni5Mg/CZO (S) catalyst exhibited the best catalytic stability for MPO after 18 h on stream at 750°C. Moreover, this catalyst had a better resistance to carbon deposition due to its high metallic Ni dispersion at high temperature.

关键词: methane partial oxidation     NiO     ceria-zirconia     MgO     mixed oxide solid solution    

Enhanced nutrients removal from municipal wastewater through biological phosphorus removal followed by partial

Yandong Yang,Liang Zhang,Hedong Shao,Shujun Zhang,Pengchao Gu,Yongzhen Peng

《环境科学与工程前沿(英文)》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0911-0

摘要: EBPR and PN/A were combined to enhance nutrients removal from municipal wastewater. High effluent quality of 0.25 mg TP?L and 10.8 mg TN?L was obtained. Phosphorus and nitrogen removal was achieved in two separated units. A proper post-anoxic phase improved the nitrogen removal performance of PN/A unit. Conventional biological removal of nitrogen and phosphorus is usually limited due to the lack of biodegradable carbon source, therefore, new methods are needed. In this study, a new alternative consisting of enhanced biological phosphorus removal (EBPR) followed by partial nitritation-anammox (PN/A), is proposed to enhance nutrients removal from municipal wastewater. Research was carried out in a laboratory-scale system of combined two sequencing batch reactors (SBRs). In SBR1, phosphorus removal was achieved under an alternating anaerobic-aerobic condition and ammonium concentration stayed the same since nitrifiers were washed out from the reactor under short sludge retention time of 2–3 d. The remaining ammonium was further treated in SBR2 where PN/A was established by inoculation. A maximum of nitrogen removal rate of 0.12 kg N?m ?d was finally achieved. During the stable period, effluent concentrations of total phosphorus and total nitrogen were 0.25 and 10.8 mg?L , respectively. This study suggests EBPR-PN/A process is feasible to enhance nutrients removal from municipal wastewater of low influent carbon source.

关键词: Phosphorus removal     Partial nitrification     Anammox     Municipal wastewater    

Partial liver transplantation

null

《医学前沿(英文)》 2011年 第5卷 第1期   页码 1-7 doi: 10.1007/s11684-010-0105-7

摘要:

Partial liver transplantation, including reduced-size liver transplantation, split liver transplantation, and living donor liver transplantation, has been developed with several innovative techniques because of donor shortage. Reduced-size liver transplantation is based on Couinaud’s anatomical classification, benefiting children and small adult recipients but failing to relieve the overall donor shortage. Split liver transplantation provides chances to two or even more recipients when only one liver graft is available. The splitting technique must follow stricter anatomical and physiological criteria either ex situ or in situto ensure long-term quality. The first and most important issue involving living donor liver transplantation is donor safety. Before surgery, a series of donor evaluations—including anatomical, liver volume, and liver function evaluations—is indispensable, followed by ethnic agreement. At different recipient conditions, auxiliary liver transplantation and auxiliary partial orthotopic liver transplantation, which employ piggyback techniques, are good alternatives. Partial liver transplantation enriches the practice and knowledge of the transplant society.

关键词: partial liver transplantation     reduced-size liver transplantation     split liver transplantation     living donor liver transplantation    

Optimal Su-Do-Ku based interconnection scheme for increased power output from PV array under partial

P. SRINIVASA RAO,P. DINESH,G. SARAVANA ILANGO,C. NAGAMANI

《能源前沿(英文)》 2015年 第9卷 第2期   页码 199-210 doi: 10.1007/s11708-015-0350-1

摘要: Partial shading is a common phenomenon in PV arrays. They drastically reduce the power output because of mismatch losses, which are reliant on the shape of the shade as well as the locations of shaded panels in the array. The power output can be improved by distributing the shade over various rows to maximize the current entering the node. A Su-Do-Ku configuration can be used to rearrange the physical locations of the PV modules in a total cross tied PV array with the electrical connections left unchanged. However, this arrangement increases the length of the wire required to interconnect the panels thus increasing the line losses. In this paper, an improved Su-Do-Ku arrangement that reduces the length of the wire required for the connection is proposed. The system is designed and simulated in a Matlab/Simulink environment for various shading patterns and the efficacies of various arrangements are compared. The results prove that the power output is higher in the proposed improved Su-Do-Ku reconfiguration technique compared to the earlier proposed Su-Do-Ku technique.

关键词: array configuration     mismatch losses     partial shading     line losses     Su-Do-Ku arrangement    

标题 作者 时间 类型 操作

the characterization of pore structures and permeability of diesel contaminated clays under different aging

期刊论文

Mechanism and characterization of microplastic aging process: A review

期刊论文

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based on

期刊论文

Insights into influence of aging processes on zero-valent iron modified biochar in copper(II) immobilization

期刊论文

Projections of heat-related excess mortality in China due to climate change, population and aging

期刊论文

Methanation and chemolitrophic nitrogen removal by an anaerobic membrane bioreactor coupled partial nitrification

期刊论文

Partial pressures” of humid air in wide pressure and temperature ranges

Zidong WANG, Hanping CHEN, Shilie WENG

期刊论文

Outdoor aging of road asphalt and SBS modified asphalt

Li XIANG, Juan TU, Jian CHENG, Guohe QUE

期刊论文

Role of brown adipose tissue in metabolic syndrome, aging, and cancer cachexia

null

期刊论文

Effect of styrene-butadiene-styrene copolymer on the aging resistance of asphalt: An atomistic understanding

期刊论文

Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

期刊论文

Methane partial oxidation over NiO-MgO/Ce

Piyawat PUE-ON, Vissanu MEEYOO, Thirasak RIRKSOMBOOON

期刊论文

Enhanced nutrients removal from municipal wastewater through biological phosphorus removal followed by partial

Yandong Yang,Liang Zhang,Hedong Shao,Shujun Zhang,Pengchao Gu,Yongzhen Peng

期刊论文

Partial liver transplantation

null

期刊论文

Optimal Su-Do-Ku based interconnection scheme for increased power output from PV array under partial

P. SRINIVASA RAO,P. DINESH,G. SARAVANA ILANGO,C. NAGAMANI

期刊论文