检索结果-南通市图书馆

Germanium/silica ratio and trace element composition of Early Cambrian siliceous rocks in Keping:implications for the siliceous rocks'formation and paleoenvironment interpretations

引用

Acta Geochimica 2020年第6期39卷 797-810页

作者： Zixuan Guan Shibiao Deng Peixian Liu Yiqiu Jin xingchun cao MOE Key Laboratory od Orogenic Belts and Crustal Evolution School of Earth and Space SciencePeking UniversityBeijing 100871China Research Institute of Petroleum Exploration and Development CNPCBeijing 100083China

This study used the germanium/silica(Ge/Si)ratios,together with rare earth elements and other trace elements to infer the siliceous source and sedimentary environment of the siliceous rocks located at the bottom of Yuertusi Formation in Northwestern Tarim Basin,Keping,*** studies have shown that this siliceous rock stratum formed at the edge of the carbonate platform on the continental *** suggest that these siliceous rocks were formed by hydrothermal activity,but some still draw different *** the silicon source and depositional environment of these siliceous rocks would help us learn the processes of environmental changes and the causes of biological explosions during this *** value of germanium/silica ratios of these siliceous rocks is from 0.15 to 0.37 pmol/mol and much lower than above 10|imol/mol values in siliceous rocks that are known formed by hydrothermal *** samples are rich in HREE,which differ from hydrothermal siliceous rocks that are rich in *** samples lack hydrothermal related *** these features show that the source of these siliceous rocks'siliceous is not hydrothermal flu *** samples'Ce/Ce*range from 0.88 to 1,and Th/U ratios range from 0.01 to *** features suggest these siliceous rocks were formed in an anoxic *** all the evidence,we conclude that the siliceous rock stratum at the bottom of the Lower Cambrian Yuertusi Formation in northwest Tarim ***,was formed in anoxic seawater at the edge of the carbonate platform on the continental *** silicon source is seawater instead of hydrothermal fluid.

关键词： Siliceous rocks Trace elements Ge/Si ratio Tarim Basin

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

Aperiodically semi-intermittent-based fixed-time stabilization and synchronization of delayed discontinuous inertial neural networks

引用

Science China(Information Sciences) 2025年第1期68卷 238-254页

作者： Guodong ZHANG Jinde cao School of Mathematics and Statistics South-Central Minzu University School of Mathematics Southeast University

This article concentrates on the fixed-time stabilization(FS) and fixed-time synchronization(FTS) of discontinuous inertial neural networks(DINNs) with distributed delays. Using mathematical induction to a new differential equality, a novel fixed-time stability lemma is constructed. Then, by designing an aperiodically semi-intermittent switching control and combining it with the theory of nonsmooth analysis, some novel criteria on the FS and FTS of DINNs are obtained. Unlike the methods used in most existing studies, the FS and FTS results are structured using the newly proposed fixed-time stability lemma and the nonreduced-order approach, resulting in broader practical applications and strengthening the scientific quality of the derived results. Lastly, numerical simulations and applications proffer the effectiveness of the established FS and FTS criteria.

关键词： inertial neural networks fixed-time synchronization semi-intermittent switching control nonreduced-order approach fixed-time stabilization

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Study on the off situ reconstruction of the core neutron field based on dual-task hybrid network architecture

引用

Nuclear Science and Techniques 2025年第1期36卷 175-191页

作者： Pei cao Hui Ding Cheng-Long cao Zi-Hui Yang Guo-Min Sun School of Artificial Intelligence and Big Data Hefei UniversityHefei 230001China College of Electronic Engineering National University of Defense TechnologyHefei 230001China Institute of Nuclear Energy Safety Technology HFIPSChinese Academy of SciencesHefei 230027China

The off situ accurate reconstruction of the core neutron field is an important step in realizing real-time reactor *** existing off situ reconstruction method of the neutron field is only applicable to cases wherein a single region changes at a specified location of the ***,when the neutron field changes are complex,the accurate identification of the individual changed regions becomes challenging,which seriously affects the accuracy and stability of the neutron field ***,this study proposed a dual-task hybrid network architecture(DTHNet)for off situ reconstruction of the core neutron field,which trained the outermost assembly reconstruction task and the core reconstruction task jointly such that the former could assist the latter in the reconstruction of the core neutron field under core complex ***,to exploit the characteristics of the ex-core detection signals,this study designed a global-local feature upsampling module that efficiently distributed the ex-core detection signals to each reconstruction unit to improve the accuracy and stability of *** experiments were performed on the simulation datasets of the CLEAR-I reactor to verify the accuracy and stability of the proposed *** results showed that when the location uncertainty of a single region did not exceed nine and the number of multiple changed regions did not exceed ***,the reconstructed ARD was within 2%,RD_(max)was maintained within 17.5%,and the number of RD≥10%was maintained within ***,when the noise interference of the ex-core detection signals was within±2%,although the average number of RD≥10%increased to 16,the average ARD was still within in 2%,and the average RD_(max)was within 22%.Collectively,these results show that,theoretically,the DTHNet can accurately and stably reconstruct most of the neutron field under certain complex core changes.

关键词： Real-time reactor monitoring Core neutron field reconstruction Dual-task hybrid network architecture Global-local feature upsampling module

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

Effect of lysozyme combined with hydrothermal pretreatment on excess sludge and anaerobic digestion

引用

Journal of Environmental Sciences 2025年第1期147卷 36-49页

作者： Xiuqin cao Songyue Li Chaolei Liu School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Key Laboratory of Urban Storm water System and Water Environment(Ministry of Education) Beijing University of Civil Engineering and ArchitectureBeijing 100044China

Anaerobic digestion(AD)is widely employed for sludge stabilization and waste ***,the slow hydrolysis process hinders methane production and leads to prolonged sludge *** this study,an efficient and eco-friendly lysozyme pre-treatment method was utilized to address these *** optimizing lysozyme dosage,hydrolysis and cell lysis were ***,lysozyme combined with hydrothermal pretreatment enhanced overall *** indicate that:(1)When lysozyme dosage reached 90 mg/g TS after 240 min of pretreatment,SCOD,soluble polysaccharides,and protein content reached their maxima at 855.00,44.09,and 204.86 mg/L,*** represented an increase of 85.87%,365.58%,and 259.21%compared to the untreated *** fluorescence spectroscopy revealed the highest fluorescence intensity in the IV region(soluble microbial product),promoting microbial metabolic activity.(2)Lysozyme combined with hydrothermal pretreatment significantly increased SCOD,soluble proteins,and polysaccharide release from sludge,reducing SCOD release *** experiments identified Group 3 as the most effective for SCOD and soluble polysaccharide release,while Group 9 released the most soluble *** significance order of factors influencing SCOD,soluble proteins,and polysaccharide release is hydrothermal temperature>hydrothermal time>enzymatic digestion time.(3)The lysozyme-assisted hydrothermal pretreatment group exhibited the fastest release and the highest SCOD concentration of 8,135.00 mg/L during anaerobic *** SCOD consumption and cumulative gas production increased by 95.89%and 130.58%,respectively,compared to the control group,allowing gas production to conclude 3 days earlier.

关键词： Excess sludge Lysozyme Hydrothermal pre-treatment Anaerobic digestion Gas production

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

A Simulation Study to Assess Impacts of Habitat-Dependent Parameters of Surplus Production Model on Stock Assessment of Chilean Jack Mackerel in the Southeast Pacific Ocean

引用

Journal of Ocean University of China 2025年第1期24卷 169-181页

作者： LI Gang cao Yangming cao Jie CHEN Xinjun ZOU Xiaorong College of Marine Science Shanghai Ocean UniversityShanghai 201306China National Engineering Research Center for Oceanic Fisheries Shanghai 201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai 201306China Department of Applied Ecology Center for Marine Sciences and TechnologyNorth Carolina State UniversityMorehead CityNC 28557USA

Pelagic fish are the most abundant species in upwelling regions,contributing 25%of total global fisheries ***-driven changes in the marine environment play a crucial role in their population *** Chilean jack mackerel(Trachurus murphyi)as an example,this study conducted simulations to quantify the impacts of environmental variations on the stock assessment.A habitat-based surplus production model was developed by integrating suitable habitat area into the model parameters carrying capacity(K)and intrinsic growth rate(r),with a suitable habitat area serving as the proxy for the environmental conditions for Chilean jack mackerel in the Southeast Pacific *** dynamics of Chilean jack mackerel stock and fisheries data were simulated,and four assessment models with different configurations were built to fit simulated data,with or without considering environmental *** results indicated that Joint K-r model,which integrated both parameters with the suitable habitat area index,outperformed the others by coming closest to the‘true'population *** habitat variations in the estimation model tended to overestimate biomass and underestimate harvest rate and reference *** observation and process error,the results were estimated with bias,while FMSY is relatively *** research illustrates the importance to consider random errors and environmental influences on populations,and provides foundation guidelines for future stock assessment.

关键词： Trachurus murphyi simulations suitable habitat area stock assessment errors Southeast Pacific Ocean

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

Energy injection, transport, and dissipation in Earth's magnetosphere

引用

Science China Earth Sciences 2025年第2期68卷 363-388页

作者： Huishan FU Jinbin cao School of Space and Earth Sciences Beihang UniversityBeijing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100191China

The Earth's magnetosphere is a region occupied by many artificial satellites, and also is a region that spacecraft must cruise during the deep-space exploration. In this sense, the Earth's magnetosphere is closely related to human activity and is a candidate for us to expand our living space. Generally, the Earth's magnetosphere can preclude most energetic particles from the Sun and the interstellar space, effectively protecting human beings on the Earth from being attacked and thus making the Earth to be a habitable planet. However, in some conditions, the Earth's magnetosphere becomes dynamic and energetic, and consequently may damage the artificial satellites, threaten the astronauts' health, and disrupt the ground infrastructure, which leads to a decline in the national economy. Therefore, investigating how energy is injected into the magnetosphere, how it is transported in the magnetosphere, and how it is ultimately dissipated in the magnetosphere are the key issues in space physics. Targeting these key issues, in this paper, we review the recent progress on them. Particularly, we introduce the relevant scientific questions,models, methods, and spacecraft missions, for better building a physical link among the energy injection, transport, and dissipation in the magnetosphere, present an energy chain of the magnetosphere, reveal the relationship between such energy chain and the space weather events, and discuss the forecasting and warning methods for energetic-particle events in the magnetosphere. The magnetospheric energy chain discussed in this paper will help us reveal the mechanisms of space weather events, establish the models of space environment, and forecast the disastrous space weather events.

关键词： Earth's magnetosphere Energy injection Energy transport Energy dissipation

来源：

维普期刊数据库

同方期刊数据库

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

Failure rate analysis and maintenance plan optimization method for civil aircraft parts based on data fusion

引用

Chinese Journal of Aeronautics 2025年第1期38卷 306-324页

作者： Kang cao Yongjie ZHANG Jianfei FENG School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Shanghai 201210China

In the face of data scarcity in the optimization of maintenance strategies for civil aircraft,traditional failure data-driven methods are encountering challenges owing to the increasing reliability of aircraft *** study addresses this issue by presenting a novel combined data fusion algorithm,which serves to enhance the accuracy and reliability of failure rate analysis for a specific aircraft model by integrating historical failure data from similar models as supplementary *** a comprehensive analysis of two different maintenance projects,this study illustrates the application process of the *** upon the analysis results,this paper introduces the innovative equal integral value method as a replacement for the conventional equal interval method in the context of maintenance schedule *** Monte Carlo simulation example validates that the equivalent essential value method surpasses the traditional method by over 20%in terms of inspection efficiency *** discovery indicates that the equal critical value method not only upholds maintenance efficiency but also substantially decreases workload and maintenance *** findings of this study open up novel perspectives for airlines grappling with data scarcity,offer fresh strategies for the optimization of aviation maintenance practices,and chart a new course toward achieving more efficient and cost-effective maintenance schedule optimization through refined data analysis.

关键词： Small sample data Data fusion Failure rate Maintenance planning Aircraft parts

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

Advancing gravitational theory through the tetrahedral constellation gravitational wave observatory

引用

Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 197-198页

作者： Yun-Yong Wang Zhou-Jian cao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing102206China

The Tetrahedral Constellation Gravitational Wave Observatory(TEGO)[1]represents a significant leap forward in gravitational wave detection,advancing our understanding of gravitational *** introducing a fourth spacecraft to form a tetrahedral configuration,TEGO enhances traditional triangular setups,enabling the simultaneous sensitivity to all six gravitational wave polarization modes,including those not predicted by general relativity.

关键词： wave polarization theory

来源：

维普期刊数据库

同方期刊数据库

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

钛白粉三洗废水循环回用技术的工程实践

引用

给水排水 2022年第5期48卷 55-59页

作者：孟付明李娜徐正强曹行春李丕成济南市市政工程设计研究院(集团)有限责任公司济南250013 山东奥美环境股份有限公司济南250101

以徐州钛白化工有限公司1200 m^(3)/d三洗废水循环回用项目为例,创新性的提出了“冷却塔+高密度沉淀池+超滤+纳滤+反渗透”的膜主体处理工艺,处理后的水循环回用于钛白粉生产过程中二洗冲洗偏钛酸杂质用水,回用率≥80%。本工艺运行稳定... 详细信息

以徐州钛白化工有限公司1200 m^(3)/d三洗废水循环回用项目为例,创新性的提出了“冷却塔+高密度沉淀池+超滤+纳滤+反渗透”的膜主体处理工艺,处理后的水循环回用于钛白粉生产过程中二洗冲洗偏钛酸杂质用水,回用率≥80%。本工艺运行稳定,单位水量处理费用较低,可为硫酸法钛白粉行业生产三洗废水循环回用,实现清洁生产和节能减排双重目标提供借鉴。

关键词：钛白粉三洗废水循环回用膜工艺

来源：

维普期刊数据库

同方期刊数据库

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

Spatial differentiation of carbon emissions from energy consumption based on machine learning algorithm:A case study during 2015–2020 in Shaanxi,China

引用

Journal of Environmental Sciences 2025年第3期149卷 358-373页

作者： Hongye cao Ling Han Ming Liu Liangzhi Li China Jikan Research Institute of Engineering Investigations and Design Co.Ltd.Xi’an 710043China College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710061China School of Land Engineering Chang’an UniversityXi’an 710064China Xi’an Key Laboratory of Territorial Spatial Information School of Land EngineeringChang’an UniversityXi’an 710064China Department of Geography and Environmental Management University of WaterlooWaterlooOntario N2L 3G1Canada

Carbon emissions resulting from energy consumption have become a pressing issue for governments *** estimation of carbon emissions using satellite remote sensing data has become a crucial research *** studies relied on statistical regression models that failed to capture the complex nonlinear relationships between carbon emissions and characteristic *** this study,we propose a machine learning algorithm for carbon emissions,a Bayesian optimized XGboost regression model,using multi-year energy carbon emission data and nighttime lights(NTL)remote sensing data from Shaanxi Province,*** results demonstrate that the XGboost algorithm outperforms linear regression and four other machine learning models,with an R^(2)of 0.906 and RMSE of *** observe an annual increase in carbon emissions,with high-emission counties primarily concentrated in northern and central Shaanxi Province,displaying a shift from discrete,sporadic points to contiguous,extended spatial *** autocorrelation clustering reveals predominantly high-high and low-low clustering patterns,with economically developed counties showing high-emission clustering and economically relatively backward counties displaying low-emission *** findings show that the use of NTL data and the XGboost algorithm can estimate and predict carbon emissionsmore accurately and provide a complementary reference for satellite remote sensing image data to serve carbon emission monitoring and *** research provides an important theoretical basis for formulating practical carbon emission reduction policies and contributes to the development of techniques for accurate carbon emission estimation using remote sensing data.

关键词： Machine learning Energy carbon emissions Nighttime light Spatial distribution

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

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：