检索结果-南通市图书馆

Microstructure Evolution and Mechanism of Strength Development of Fly Ash Paste

Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 152-163页

作者： MA Shuzhao WU Shunchuan HUANG Mingqing CHENG Haiyong JIANG Guanzhao NIU Yonghui LIU Zemin SUN Wei Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Zijin School of ge-ology and Mining Fuzhou UniversityFuzhou 350108China

Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash *** conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the *** mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were *** results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased *** the content exceeded 4%,the rate of increase in strength *** on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping *** activation effect was poor for long-term strength after 28 *** CaO content did not significantly affect the degree of activation *** maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the *** activators also corroded the surface of the fly ash particles,resulting in a pozzolanic *** active substances in fly ash were released efficiently,and hydration was *** pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.

关键词： paste filling fly ash activator unconfined compressive strength microstructure hydration simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Inability of recognizing offspring underlies parental errors in the selection of offspring

引用

AVIAN RESEARCH 2025年第1期16卷

作者： Gao, Lifang Zhang, Wen Zhu, Wenjing Wu, Yichen Xu, Ran Sun, Ningning Wang, Yujie Jia, Biyun Du, Bo Northwest Normal Univ Coll Life Sci Lanzhou 730070 Peoples R China Lanzhou Univ Sch Life Sci Lanzhou 730000 Peoples R China Lanzhou Univ Coll Ecol Lanzhou 730000 Peoples R China

Inclusive fitness theory posits that altruistic behaviors, which are directed more likely towards relatives, should be favored by natural selection. However, the prevalence of alternative parenting behaviors in offspring selection, including rejecting their own offspring and accepting the offspring of others, remains poorly understood within the context of parental care evolution. In order to investigate the factors that prompt the occurrence of alternative parenting behaviors, we designed a series of experiments in the Azure-winged Magpie (Cyanopica cyanus). By manipulating the nest spatial position or offspring age/number and parent-offspring familiarity, we addressed how parents provided parental care for the manipulated offspring. In the nest resettlement experiment, the probability of parents rejecting their own offspring significantly increased with nest-moving distances while decreased with offspring ages. In the cross-fostering experiments, the probability of parents provisioning unrelated young significantly decreased with the age difference between cross-fostered chicks. In the nest duplication experiments, where parents were given a choice between familiar offspring and unfamiliar unrelated chicks or between unfamiliar offspring and familiar unrelated chicks, the probability of both alternative parenting behaviors was significantly influenced by the time when parental association with their offspring was deprived. We conclude that as offspring phenotypic traits become individualized and fixed at a special developmental stage, parents gradually acquire the capacity for offspring recognition by associating with them. Any factors that disrupt parent-offspring association or introduce unrelated young into the nest prior to this critical timeline can result in the occurrence of alternative parenting behaviors.

关键词： Cross-foster Cyanopica cyanus Offspring recognition Parental care Parent-offspring association

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Toward diagnostic relevance of theαVβ5,αVβ3,andαVβ6 integrins in OA:expression within human cartilage and spinal osteophytes

引用

Bone Research 2020年第4期8卷 458-472页

作者： Edith Charlier Céline Deroyer Sophie Neuville Zelda Plener Olivier Malaise Federica Ciregia Philippe Gillet Gilles Reuter Mallory Salvé Nadia Withofs Roland Hustinx Dominique de Seny Michel G.Malaise Laboratory of Rheumatology GIGA-I3CHULiègeULiègeLiègeBelgium Department of Orthopaedic Surgery CHULiègeLiègeBelgium Department of Neurosurgery CHULiègeLiègeBelgium Department of Nuclear Medicine CHULiègeLiègeBelgium

We previously reported 18FPRGD2 uptake by the coxofemoral lining,intervertebral discs and facet joint osteophytes in OA using PET/SCAN ***,the molecular mechanism by which the PRGD2 tracer interacts with joint tissues and osteophytes in OA remains *** PRGD2 ligands are expected to belong to the RGD-specific integrin family,the purpose of this study was(i)to determine which integrin complexes display the highest affinity for PRGD2-based ligands,(ii)to analyze integrin expression in relevant tissues,and(iii)to test integrin regulation in chondrocytes using OA-related stimuli to increase the levels of fibrosis and ossification *** this end,the affinity of PRGD2-based ligands for five heterodimeric integrins was measured by competition with *** situ analyses were performed in human normal *** cartilage and spinal *** were characterized by(immuno-)histological *** subunit expression was tested in chondrocytes undergoing dedifferentiation,osteogenic differentiation,and inflammatory *** integrinsαVβ5,αVβ3,andαVβ6 presented the highest affinity for PRGD2-based *** situ,the expression of these integrins was significantly increased in OA compared to normal *** osteophytes,the mean integrin expression score was significantly higher in blood vessels,fibrous areas,and cells from the bone lining than in osteocytes and cartilaginous *** vitro,the levels of integrin subunits were significantly increased during chondrocyte dedifferentiation(except forβ6),fibrosis,and osteogenic differentiation as well as under inflammatory *** conclusion,anatomical zones(such as OA cartilage,intervertebral discs,and facet joint osteophytes)previously reported to show PRGD2 ligand uptake in vivo expressed increased levels ofαVβ5,αVβ3,andβ6 integrins,whose subunits are modulated in vitro by OA-associated conditions that increase fibrosis,inflammation,and osteogenic differentiation.T

关键词： cartilage inflammation femoral

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Meta-analysis of 21st century studies shows that deforestation induces profound changes in soil characteristics, particularly soil organic carbon accumulation

引用

FOREST ECOSYSTEMS 2025年第1期12卷 46-55页

作者： Mgelwa, Abubakari Said Ngaba, Mbezele Junior Yannick Hu, Bin Gurmesa, geshere Abdisa Mwakaje, Agnes Godfrey Nyemeck, Mateg Pascale Bernadette Zhu, Feifei Qiu, Qingyan Song, Linlin Wang, Yingying Fang, Yunting Rennenberg, Heinz Chinese Acad Sci Inst Appl Ecol CAS Key Lab Forest Ecol & Management Shenyang 110016 Peoples R China Key Lab Stable Isotope Tech & Applicat Shenyang 110016 Peoples R China Mwalimu Julius K Nyerere Univ Agr & Technol Coll Nat Resources Management & Tourism POB 976 Musoma Tanzania Southwest Univ Coll Resources & Environm Ctr Mol Ecophysiol CMEP Chongqing 400715 Peoples R China Univ Ebolowa HTTTC Higher Tech TeacherTraining Coll Ebolowa Ebolowa 886 Cameroon Multipolar Consulting Firm Yaounde 1092 Cameroon Chinese Acad Sci Qingyuan Forest CERN Shenyang 110016 Peoples R China Fujian Agr & Forestry Univ Coll Forestry Forest Ecol Stable Isotope Ctr Fuzhou 350002 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

Deforestation is one of the most serious environmental problems facing humankind. It continues to escalate rapidly across many regions of the world, thereby deteriorating the forest soil quality. This has prompted a large number of field-based studies aimed at understanding the impacts of deforestation on soil properties. However, the lack of comprehensive meta-analyses that utilized these studies has limited our deeper understanding of how different soil properties, including the soil organic carbon (SOC) pool, respond to deforestation. To address this critical knowledge gap, we conducted a meta-analysis of 144 studies to explore the impacts of deforestation on soil chemical, physical, and biological properties, with special emphasis on the long-term changes in SOC, such as concentrations, stocks, and sequestration. The results revealed that deforestation significantly decreased soil organic matter, electrical conductivity, and base saturation by 52%, 50%, and 98%, respectively. While deforestation increased soil total nitrogen content and decreased available phosphorus content by 51% and 99%, respectively, it resulted in slight decreases in some chemical properties, including soil pH (1%) and base cations (1%-13%). Deforestation significantly increased bulk density by 27% and soil erosion by 47%, but significantly decreased soil aggregate stability by 39% and saturated hydraulic conductivity by 63%. Soil microbial biomass C and N concentrations and enzyme activities were significantly decreased as a consequence of deforestation. Soil biological properties were much more affected by deforestation than soil physical and chemical properties. Regarding the SOC, the land use conversion from forest to pasture significantly increased SOC concentrations, stocks, and sequestration rates (11%-13%), whereas the land use conversions from forest to both plantation and cropland significantly decreased SOC concentrations, stocks, and sequestration rates (10%-43%). This observed

关键词： Deforestation Land-use change Soil properties Soil organic carbon

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High temperature X-ray diffraction study of the formation of Na_(2)Ti_(3)O_(7) from a mixture of sodium carbonate and titanium oxide

引用

Journal of Energy Chemistry 2022年第2期31卷 210-218页

作者： Caroline Piffet Bénédicte Vertruyen Frédéric Hatert Rudi Cloots Frédéric Boschini Abdelfattah Mahmoud GREENMAT CESAM Research UnitChemistry DepartmentUniversity of Liège4000 LiègeBelgium Laboratory of Mineralogy Geology Research UnitUniversity of Liège4000 LiègeBelgium

Na2Ti3O7 has attracted much attention in the field of anode materials for Na-ion batteries thanks to its non-toxicity and very low working potential of 0.3 V vs Na0/Na+.Building a clearer picture of its formation from cheap Na_(2)CO_(3) and TiO_(2) starting materials is therefore of obvious ***,we report new insights from an in-situ high temperature X-ray diffraction study conducted from room temperature to 800°C,complemented by ex-situ *** were thereby able to position the previously reported Na_(4)Ti_(5)O_(12) and Na_(2)Ti_(6)O_(13) intermediate phases in a reaction scheme involving three successive steps and temperature *** and/or broadening of a subset of the Na_(2)Ti_(6)O_(13) reflections suggested a combination of intra-layer disorder with the well-established ordering of successive *** in-situ study was carried out on reproducible mixtures of Na_(2)CO_(3) and TiO_(2) in 1:3 molar ratio prepared by spraydrying of mixed aqueous ***-phase Na_(2)Ti_(3)O_(7) was obtained after only 8 h at 800°C in air,instead of a minimum of 20 h for a conventional solid-state route using the same *** analysis revealed~15 mm diameter granules made up from rectangular rods of a fewmm length presenting electrochemical properties in line with *** the absence of grinding or formation of intimate composites with conductive carbon,the specific capacity of 137 m Ah/g at C/5 decreased at higher rates.

关键词： Formation mechanism High temperature XRD Na_(2)Ti_(3)O_(7) Spray-drying synthesis Na-ion batteries

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Independent and interactive effects of N and P additions on foliar P fractions in evergreen forests of southern China

引用

FOREST ECOSYSTEMS 2025年第1期12卷 66-73页

作者： Meng, Qingquan Shi, Zhijuan Yan, Zhengbing Lambers, Hans Luo, Yan Han, Wenxuan China Agr Univ Minist Educ Coll Resources & Environm Sci Key Lab Plant Soil Interact Beijing 100193 Peoples R China Chinese Acad Sci Inst Bot Beijing 100093 Peoples R China Univ Western Australia Sch Biol Sci Perth WA 6009 Australia Xinjiang Univ Educ Minist Coll Ecol & Environm Key Lab Oasis Ecol Urumqi 830017 Peoples R China

Fertilization or atmospheric deposition of nitrogen (N) and phosphorus (P) to terrestrial ecosystems can alter soil N (P) availability and the nature of nutrient limitation for plant growth. Changing the allocation of leaf P fractions is potentially an adaptive strategy for plants to cope with soil N (P) availability and nutrient-limiting conditions. However, the impact of the interactions between imbalanced anthropogenic N and P inputs on the concentrations and allocation proportions of leaf P fractions in forest woody plants remains elusive. We conducted a meta- analysis of data about the concentrations and allocation proportions of leaf P fractions, specifically associated with individual and combined additions of N and P in evergreen forests, the dominant vegetation type in southern China where the primary productivity is usually considered limited by P. This assessment allowed us to quantitatively evaluate the effects of N and P additions alone and interactively on leaf P allocation and use strategies. Nitrogen addition (exacerbating P limitation) reduced the concentrations of leaf total P and different leaf P fractions. Nitrogen addition reduced the allocation to leaf metabolic P but increased the allocation to other fractions, while P addition showed opposite trends. The simultaneous additions of N and P showed an antagonistic (mutual suppression) effect on the concentrations of leaf P fractions, but an additive (summary) effect on the allocation proportions of leaf P fractions. These results highlight the importance of strategies of leaf P fraction allocation in forest plants under changes in environmental nutrient availability. Importantly, our study identified critical interactions associated with combined N and P inputs that affect leaf P fractions, thus aiding in predicting plant acclimation strategies in the context of intensifying and imbalanced anthropogenic nutrient inputs.

关键词： Anthropogenic nutrient inputs Individual and combined effects Interactive effects Leaf phosphorus fractions Nitrogen and phosphorus additions Nutrient-utilization strategies Woody plants

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Simulation of Urban Mobility between Azove and Aplahoue Using a geographic Information System

引用

Journal of geoscience and Environment Protection 2025年第1期13卷 475-494页

作者： Apollinaire Cyriaque Agbon Department of geography and Regional Planning CU-Adjarra FASHS University of Abomey-Calavi Abomey-Calavi Benin geomatics Applications and Environmental Management Laboratory (LA2ge) CU-Adjarra FASHS University of Abomey-Calavi Abomey-Calavi Benin

People, goods and services’ mobility is increasing in the cities of Azovè and Aplahoué. This research aims at simulating urban mobility between these two cities using the geographic Information System. The data was collected through individual interviews with 115 people using a questionnaire. GPS was then used to collect the geographical coordinates of existing infrastructure in the two cities. The roads were identified, categorized and mapped using the data available on the IGN’s 1:50,000 Aplahoué topographic sheet. By calculating the frequencies of the responses, we were able to identify the most frequently used roads, factors and purposes of mobility. These frequencies and the coordinates collected were used to categorize the roads and map them using the Graduted symbols tool in Quantities under ArcGis 10.7 software. Population growth, the extension of urban areas, the increase in commercial and service infrastructures, the rehabilitation of certain roads and the transport of farming products, goods and people associated with the Tohoun border between Benin and Togo are the factors driving urban mobility. This research has shown the infrastructures responsible for this mobility and the spatial structuring of these cities. It has also shown the main current and future routes for urban mobility as well as the traffic development hubs.

关键词： Forecast Mapping Mobility Trunk Road Aplahoué-Azovè

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

深度学习重建算法对胸部CT图像质量及肺结节影像组学特征数据可重复性的影响

引用

中国医学影像技术 2025年第1期41卷 79-83页

作者：郑志娟李姝霖马昆向之明广州医科大学附属番禺中心医院放射科广东广州511400 ge医疗CT影像研究中心广东广州510623

目的与自适应统计迭代重建(ASIR-V)算法比较,观察深度学习图像重建(DLIR)对于胸部CT图像质量、肺结节检出率及肺结节影像组学特征数据可重复性的影响。方法前瞻性纳入75例同期接受胸部超低剂量CT(ULD-CT)及标准剂量CT(SDCT)检查的肺结... 详细信息

目的与自适应统计迭代重建(ASIR-V)算法比较,观察深度学习图像重建(DLIR)对于胸部CT图像质量、肺结节检出率及肺结节影像组学特征数据可重复性的影响。方法前瞻性纳入75例同期接受胸部超低剂量CT(ULD-CT)及标准剂量CT(SDCT)检查的肺结节患者、共211个肺结节,分别以高强度DLIR(DLIR-H)、中强度DLIR(DLIR-M)及50%水平ASIR-V算法(50%ASIR-V)重建ULD-CT图像,以50%ASIR-V获得SDCT图像。针对ULD-CT和SDCT图像,以相同ROI内肺实质CT值标准差(SD)代表噪声并计算信噪比(SNR);计算肺结节检出率,并在不同图像间加以比较。基于自动分割法提取50%ASIR-V SDCT及各ULD-CT肺结节影像组学特征,分别计算各ULD-CT与50%ASIR-V SDCT影像组学特征的组内相关系数(ICC),并与不同ULD-CT算法进行比较。结果相比50%ASIR-V SDCT图像,以不同算法重建的ULD-CT图像SD均较高而SNR均较低(P均0.05)。基于3种算法重建的ULD-CT所获肺结节与50%ASIR-V SDCT一阶特征及形状特征数据的可重复性较好(中位ICC均>0.75),不同算法间差异无统计学意义(P均>0.05)。结论以DLIR-H和DLIR-M算法重建胸部ULD-CT可在降低图像噪声的同时提高图像质量,并在一定程度上维持肺结节影像学特征的可重复性,尤以DLIR-H更佳。

关键词：深度学习肺疾病体层摄影术,X线计算机影像组学前瞻性研究

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

A Quasi-One-Dimensional CFD Model for Multistage Turbomachines

引用

Journal of Thermal Science 2008年第1期17卷 7-20页

作者： Olivier Léonard Olivier Adam University of Liège-Turbomachinery Group LiegeBelgium Professor University of Liège-Turbomachinery Group LiegeBelgium

The objective of this paper is to present a fast and reliable CFD model that is able to simulate stationary and transient operations of multistage compressors and turbines. This analysis tool is based on an adapted version of the Euler equations solved by a time-marching, finite-volume method. The Euler equations have been extended by including source terms expressing the blade-flow interactions. These source terms are determined using the ve- locity triangles and a row-by-row representation of the blading at mid-span. The losses and deviations undergone by the fluid across each blade row are supplied by correlations. The resulting flow solver is a performance pre- diction tool based only on the machine geometry, offering the possibility of exploring the entire characteristic map of a multistage compressor or turbine. Its efficiency in terms of CPU time makes it possible to couple it to an optimization algorithm or to a gas turbine performance tool. Different test-cases are presented for which the calculated characteristic maps are compared to experimental ones.

关键词： multistage compressors turbines quasi-one-dimensional meanline analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Conception of tooling adapted to thixoforging of high solid fraction hot-crack-sensitive aluminium alloys

引用

Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1712-1718页

作者： G.VANEETVELD A.RASSILI J.C.PIERRET J.LECOMTE-BECKERS Thixo Unit B56University of Liège Special Metallic Materials B52University of Liège

Thixoforging is a type of semi-solid metal processing at high solid fraction (0.7<φs<1), which involves the processing of alloys in the semi-solid *** has to be adapted to this particular process to benefit shear thi... 详细信息

Thixoforging is a type of semi-solid metal processing at high solid fraction (0.7ges between material flow and *** thermal exchanges influence the high-cracking tendency and the rheology of the semi-solid material during forming, which affects parts properties and therefore their *** tests show how thermal exchanges influence quality of thixoforged parts made of 7075 aluminium alloys at high solid fraction by modifying process parameters like forming speed, tool temperature and tool thermal *** an optimum in terms of thermal exchanges has to be found between surface quality and mechanical properties of the part.A direct application is the evaluation of surface quality of thixoforged thin wall parts made of 7075 aluminium alloy.

关键词： thixoforging solid fraction near-net-shaping tooling 7075 aluminium alloys

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：