资源类型

期刊论文 85

会议视频 1

年份

2023 5

2022 12

2021 8

2020 3

2019 6

2018 4

2017 6

2016 7

2015 1

2014 1

2013 3

2012 3

2011 1

2010 5

2009 2

2008 6

2007 1

2006 2

2004 1

2003 1

展开 ︾

关键词

含水量 2

环境保护 2

CO2 加氢 1

GPS数据 1

NO3-N 1

万维网 1

专用化技术 1

主题提取；主题演化；评价方法 1

互联网体系结构 1

人工智能，内容安全，体系建设 1

以内容为中心 1

体积含水量 1

信息化 1

信息技术 1

光速不变公设 1

关键技术 1

内容传播；设备通信；机会网络；线性阈值模型 1

内容的语义 1

内容管理 1

展开 ︾

检索范围：

排序： 展示方式：

Effects of coarse and fine aggregates on long-term mechanical properties of sea sand recycled aggregate

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 754-772 doi: 10.1007/s11709-021-0711-2

摘要： Typical effects of coarse and fine aggregates on the long-term properties of sea sand recycled aggregate concrete (SSRAC) are analyzed by a series of axial compression tests. Two different types of fine (coarse) aggregates are considered: sea sand and river sand (natural and recycled coarse aggregates). Variations in SSRAC properties at different ages are investigated. A novel test system is developed via axial compression experiments and the digital image correlation method to obtain the deformation field and crack development of concrete. Supportive results show that the compressive strength of SSRAC increase with decreasing recycled coarse aggregate replacement percentage and increasing sea sand chloride ion content. The elastic modulus of SSRAC increases with age. However, the Poisson’s ratio reduces after 2 years. Typical axial stress–strain curves of SSRAC vary with age. Generally, the effect of coarse aggregates on the axial deformation of SSRAC is clear; however, the deformation differences between coarse aggregate and cement mortar reduce by adopting sea sand. The aggregate type changes the crack characteristics and propagation of SSRAC. Finally, an analytical expression is suggested to construct the long-term stress–strain curve of SSRAC.

关键词： sea sand recycled aggregate concrete     recycled coarse aggregate replacement percentage     sea sand chloride ion content     long-term mechanical properties     stress–strain curve    

HTML PDF 收藏

liquefaction and performing parametric sensitivity analysis: Considering cumulative absolute velocity and finecontent

Nima PIRHADI, Xiaowei TANG, Qing YANG, Afshin ASADI, Hazem Samih MOHAMED

《结构与土木工程前沿（英文）》 2021年 第15卷 第2期   页码 506-519 doi: 10.1007/s11709-021-0677-0

摘要： Lateral displacement due to liquefaction ( ) is the most destructive effect of earthquakes in saturated loose or semi-loose sandy soil. Among all earthquake parameters, the standardized cumulative absolute velocity ( ) exhibits the largest correlation with increasing pore water pressure and liquefaction. Furthermore, the complex effect o fine content( ) at different values has been studied and demonstrated. Nevertheless, these two contexts have not been entered into empirical and semi-empirical models to predict This study bridges this gap by adding to the data set and developing two artificial neural network (ANN) models. The first model is based on the entire range of the parameters, whereas the second model is based on the samples with values that are less than the 28% critical value. The results demonstrate the higher accuracy of the second model that is developed even with less data. Additionally, according to the uncertainties in the geotechnical and earthquake parameters, sensitivity analysis was performed via Monte Carlo simulation (MCS) using the second developed ANN model that exhibited higher accuracy. The results demonstrated the significant influence of the uncertainties of earthquake parameters on predicting

关键词： lateral spreading displacement     cumulative absolute velocity     fine content     artificial neural network     sensitivity analysis     Monte Carlo simulation    

HTML PDF 收藏

Collaborative control of fine particles and ozone required in China for health benefit

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1692-2

摘要：

● Increased DAAO offsets 3/4 of the decrease of DAAP in 2013–2020.

关键词： Excess deaths     Long-term exposure     Fine particle     Ozone    

HTML PDF 收藏

Properties of cement grout modified with ultra-fine slag

Sowmini GOPINATHAN, K B ANAND

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 58-66 doi: 10.1007/s11709-017-0383-0

摘要： The purpose of the study is to obtain a cement grout with improved performance. The grout mixes of the present study contain cement, ultra-fine slag (UFS), super plasticizer and water. Properties like flowability, bleeding, compressive strength and shrinkage of cement grouts have been studied. Rheological parameters were also studied in order to explain the grout workability. The results show that, cement replacement with slag in grouts could reduce bleeding substantially without affecting the workability of the mixes. Introduction of slag enhanced the compressive strength and reduced shrinkage reasonably. Ultra-fine slag can be used as a supplementary cementitious material in cementitious grouts in order to improve the grout behavior.

关键词： cement grout     ultra-fine slag     flowability     bleeding     viscosity    

HTML PDF 收藏

Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

《农业科学与工程前沿（英文）》 2016年 第3卷 第3期   页码 186-194 doi: 10.15302/J-FASE-2016107

摘要： As an important oil crop and a potential bioenergy crop, L. is becoming a model plant for basic research on seed lipid biosynthesis as well as seed oil content, which has always been the key breeding objective. In this review, we present current progress in understanding of the regulation of oil content in , including genetics, biosynthesis pathway, transcriptional regulation, maternal effects and QTL analysis. Furthermore, the history of breeding for high oil content in is summarized and the progress in breeding ultra-high oil content lines is described. Finally, prospects for breeding high oil content cultivars are outlined.

关键词： breeding     maternal effects     oilseed rape     QTL    

HTML PDF 收藏

Confinement properties of circular concrete columns wrapped with prefabricated textile-reinforced fine

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0955-0

摘要： This paper proposes an innovative column composed of a core column (including both reinforced concrete (RC) and plain concrete (PC) columns) and a prefabricated textile-reinforced fine concrete (TRC) shell. To study the confinement properties of TRC shells on this novel type of concrete column, 20 circular specimens, including 12 PC columns and 8 RC columns, were prepared for axial compressive tests. Four key parameters, including the column size, reinforcing ratio of the carbon textile, concrete strength, and stirrup spacing, were evaluated. The results indicated that the compressive properties of the columns were improved by increasing the reinforcing ratio of the textile layers. In the case of TRC-confined PC columns, the maximum improvement in the peak load was 56.3%, and for TRC-confined RC columns, the maximum improvement was 60.2%. Based on the test results, an analytical model that can be used to calculate the stress–strain curves of prefabricated TRC shell-confined concrete columns has been proposed. The calculated curves predicted by the proposed model agreed well with the test results.

关键词： textile-reinforced fine concrete     prefabricated shell     confined concrete column     confinement properties     stress–strain relationship    

HTML PDF 收藏

新世纪的精细化工

杨锦宗

《中国工程科学》 2002年 第4卷 第10期   页码 21-25

摘要：

指出精细化工是衡量化学工业水平的一个标志，提出并讨论了发展精细化工必须考虑的，包括环境保护、降低消耗、节约能源、合成关键技术、专用化技术、资源和科技创新等问题。

关键词： 环境保护     关键技术     节能     专用化技术     科技创新    

HTML PDF 收藏

The use of fine portions from construction and demolition waste for expansive soil stabilization: A review

Mgboawaji Claude UJILE; Samuel Jonah ABBEY

《结构与土木工程前沿（英文）》 2022年 第16卷 第7期   页码 803-816 doi: 10.1007/s11709-022-0835-z

摘要： Construction and demolition waste (CDW) are the largest waste products in the world today and competes as a viable recycled additive material in place of natural aggregates. Due to the increase in compressive strength of different mix proportions of CDW, it is also considered for reuse in concrete and subbase construction. This study shows the effect of CDW in expansive soil stabilization. The chemical and mechanical properties of these materials have shown that they are capable of developing compressive strength properties for replacement of cement with significant reduction in carbon emission. The inherent compositional properties of recycled CDW compared in this review suggests that CDW have good filler properties in highly expansive soils. Mixtures of crushed brick and recycled aggregates characterised based on chemical properties of different replacement ratios suggests that CDW of good-quality aggregates reduces swell potential of expansive soils and increased mechanical strength in pavement construction.

关键词： mixed fine portions     construction and demolition waste     expansive soil     soil stabilization    

HTML PDF 收藏

Recycled glass replacement as fine aggregate in self-compacting concrete

Yasser SHARIFI, Mahmoud HOUSHIAR, Behnam AGHEBATI

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 419-428 doi: 10.1007/s11709-013-0224-8

摘要： With increasing environmental pressure to reduce solid waste and to recycle as much as possible, the concrete industry has adopted a number of methods to achieve this goal by replacement of waste glass with concrete composition materials. Due to differences in mixture design, placement and consolidation techniques, the strength and durability of Self Compacting Concrete (SCC) may be different than those of conventional concrete. Therefore, replacement of waste glass with fine aggregate in SCC should deeply be investigated compared to conventional concretes. The aim of the present study is to investigate the effect of glass replacement with fine aggregate on the SCC properties. In present study, fine aggregate has been replaced with waste glass in six different weight ratios ranging from 0% to 50%. Fresh results indicate that the flow-ability characteristics have been increased as the waste glass incorporated to paste volume. Nevertheless, compressive, flexural and splitting strengths of concrete containing waste glass have been shown to decrease when the content of waste glass is increased. The strength reduction of concrete in different glass replacement ratios is not remarkable, thus it can be produced SCC with waste glass as fine aggregate in a standard manner.

关键词： Self Compacting Concrete (SCC)     recycle glass     fine aggregate     fresh and hardened properties    

HTML PDF 收藏

Isolating higher yielding and more stable rice genotypes in stress environments: fine-tuning a selection

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023521

摘要：

● Score index methods readily discriminate genotypes adapted to a target environment.

关键词： Aerobic rice     breeding selection     drought resilience     production capacity index     resilience capacity index     stress score index     upland    

HTML PDF 收藏

and siderite: Evidence from sorption kinetics, sequential extraction and extended X-ray absorption fine-structure

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1547-2

摘要：

• DPAA sorption followed pseudo-secondary and intra-particle diffusion models.

关键词： Diphenylarsinic acid (DPAA)     Sorption     Magnetite     Siderite     Sequential extraction     EXAFS    

HTML PDF 收藏

Comparison of analytical procedures for measuring phosphorus content of animal manures in China

null

《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 431-440 doi: 10.15302/J-FASE-2019279

摘要：

The concentration and components of manure phosphorus (P) are key factors determining potential P bioavailability and runoff. The distribution of P forms in swine, poultry and cattle manures collected from intensive and extensive production systems in several areas of China was investigated with sequential fractionation and a simplified two-step (NaHCO -NaOH/EDTA) procedures. The mean total P concentration, determined by the sequential fractionation procedure of intensive swine, poultry and cattle manure, expressed as g·kg , was 14.9, 13.4 and 5.8 g·kg , respectively, and 4.4 g·kg in extensive cattle manure. In intensive swine, poultry and cattle manure about 73%, 74% and 79% of total P, respectively, was bioavailable (i.e., P extracted by H O and NaHCO ) and 78% in extensive cattle manure. The results indicated the relative environmental risk, from high to low, of swine, poultry and cattle manure. There is considerable regional variation in animal manure P across China, which needs to be considered when developing manure management strategies.

关键词： diet phosphorus     manure phosphorus     sequential P fractionation    

HTML PDF 收藏

Chloride binding and time-dependent surface chloride content models for fly ash concrete

S. MUTHULINGAM,B. N. RAO

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 112-120 doi: 10.1007/s11709-015-0322-x

摘要： Corrosion of embedded rebars is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. Such environments can be attributed to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. Chloride ingress into concrete, essential for inducing rebar corrosion, is a complex interaction between many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely: 1) surface chloride content under tidal exposure condition; and 2) chloride binding. First, inconsistencies in surface chloride content and chloride binding models reported in literature, due to them not being in line with past research studies, are pointed out. Secondly, to avoid such inconsistencies, surface chloride content and chloride binding models for fly ash concrete are proposed based upon the experimental work done by other researchers. It is observed that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词： binding isotherms     chloride ingress     concrete     fly ash     surface chloride content    

HTML PDF 收藏

Long-term trends of fine particulate matter and chemical composition in the Pearl River Delta Economic

Xuemei WANG,Weihua CHEN,Duohong CHEN,Zhiyong WU,Qi Fan

《环境科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 53-62 doi: 10.1007/s11783-014-0728-z

摘要： Understanding the trends in PM levels is essential for formulating clean air plans. This paper analyzes PM data from various published sources for the years 2000 to 2010 in the Pearl River Delta Economic Zone (PRDEZ). The long-term variation in PM mass concentration is analyzed. Results show that PM , organic carbon (OC), elemental carbon (EC), and show a similar trend, increasing before 2005 and then decreasing slightly. The annual average PM concentration ranges from 49.1 μg·m in 2000 to 64.3 μg·m in 2010, with a peak of 84.1 μg·m in 2004. None of these 11 years meets the new National Ambient Air Quality standard (NAAQS) for PM (35 μg·m ). Overall average concentrations of OC, EC, and are 13.0, 6.5, and 11.8 μg·m , respectively. and respectively have concentrations of 1.5 μg·m and 2.9 μg·m in 2000 and 6.4 μg·m and 5.3 μg·m in 2010, with a statistically significant average annual trend of+ 0.2 μg·m ·yr and+ 0.1 μg·m ·yr . In certain geographic regions, OC and EC contribute most of the PM , while in other regions secondary water-soluble ions are more important. In general, OC and are the dominant components of PM , contributing 20.6% and 18.6%, respectively. These results provide, for the first time, a better understanding of the long-term PM characteristics and trends, on a species-by-species basis, in the PRDEZ. The results indicate that PM abatement needs to prioritize secondary species.

关键词： long-term trends     fine particulate matter     chemical components     Pearl River Delta Economic Zone (PRDEZ)    

HTML PDF 收藏

标题 作者 时间 类型 操作

Effects of coarse and fine aggregates on long-term mechanical properties of sea sand recycled aggregate

期刊论文

liquefaction and performing parametric sensitivity analysis: Considering cumulative absolute velocity and finecontent

Nima PIRHADI, Xiaowei TANG, Qing YANG, Afshin ASADI, Hazem Samih MOHAMED

期刊论文

Collaborative control of fine particles and ozone required in China for health benefit

期刊论文

章成志：基于学术文献内容的细粒度（2020年11月6日）

2022年10月14日

会议视频

Properties of cement grout modified with ultra-fine slag

Sowmini GOPINATHAN, K B ANAND

期刊论文

Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

期刊论文

Confinement properties of circular concrete columns wrapped with prefabricated textile-reinforced fine

期刊论文

新世纪的精细化工

杨锦宗

期刊论文

The use of fine portions from construction and demolition waste for expansive soil stabilization: A review

Mgboawaji Claude UJILE; Samuel Jonah ABBEY

期刊论文

Recycled glass replacement as fine aggregate in self-compacting concrete

Yasser SHARIFI, Mahmoud HOUSHIAR, Behnam AGHEBATI

期刊论文

Isolating higher yielding and more stable rice genotypes in stress environments: fine-tuning a selection

期刊论文

and siderite: Evidence from sorption kinetics, sequential extraction and extended X-ray absorption fine-structure

期刊论文

Comparison of analytical procedures for measuring phosphorus content of animal manures in China

null

期刊论文

Chloride binding and time-dependent surface chloride content models for fly ash concrete

S. MUTHULINGAM,B. N. RAO

期刊论文

Long-term trends of fine particulate matter and chemical composition in the Pearl River Delta Economic

Xuemei WANG,Weihua CHEN,Duohong CHEN,Zhiyong WU,Qi Fan

期刊论文