检索结果-南通市图书馆

China Foundry 2025年

作者： wen-tong Liu Yi-dong wu Lei Gao Jing-yang Chen Cheng-bo Xiao Xi-dong Hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The size and shape effect(SSE) of components has become a critical issue for mechanical properties, application reliability, and processing. In this study, the creep rupture life(CRL) of components with different wall thicknesses and positions in a combustion chamber casing simulator made of K439B superalloy was investigated. The intrinsic mechanisms of the SSE were explored from the dendrite structure, volume fraction and size of the γ' phase, and element segregation, etc. It is shown that this casting exhibits a strong SSE of creep rupture life, characterized by a significant difference in the CRL values up to 60% with the variation of wall thickness and position in the casing. In terms of casting technology, the influence of SSE on CRL is actually determined by the cooling rate. The SSE on the creep rupture life originates from the dendrite structure(such as the secondary dendrite arm spacing), volume fraction size of the γ' phase in the dendrite trunk, and elements segregation rate. This work may have implications for the design and application of engineering components with large sizes and complex structures.

关键词：

Obesogenic effects of six classes of emerging contaminants

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2025年第5期151卷 252-272页

作者： Siying wu Chaoyu Tong Jing Liu MOE Key Laboratory of Environmental Remediation and Ecosystem Health College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China

There is growing concern about the concept that exposure to environmental chemicals may be contributing to the obesity ***,there is no consensus on the obesogenic effects of emerging contaminants from a toxicological and environmental *** potential human exposure and experimental evidence for obesogenic effects of emerging contaminants need to be systematically *** main objective of this review is to provide recommendations for further subsequent policy development following a critical analysis of the literature for humans and experimental animals exposed to emerging *** article reviews human exposure to emerging contaminants(with a focus on antimicrobials,preservatives,water and oil repellents,flame retardants,antibiotics and bisphenols)and the impact of emerging contaminants on *** emerging contaminants have been widely detected in human biological *** studies provide evidence linking exposure to emerging contaminants to the risks of obesity in *** based on animalmodels and adipose cells show the obesogenic effects of emerging contaminants and identify modes of action by which contaminants may induce changes in body fat accumulation and lipid metabolic *** knowledge gaps in this area and future directions for further investigation are discussed.

关键词： Emerging contaminants Obesity Human exposure Preservatives Flame retardants Plasticizers Antibiotics

Autocyclic switching processes and architecture of lobes in river-dominated lacustrine deltas

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2025年第1期14卷 126-140页

作者： Zhen-Hua Xu Sheng-He wu Piret Plink-Bj?rklund Tao Zhang Da-Li Yue Qi-Hao Qian Qing Li wen-Jie Feng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) College of Geosciences China University of Petroleum (Beijing) Department of Geology and Geological Engineering Colorado School of Mines Gas Production Plant 2 PetroChina Changqing Oilfield Company PetroChina Research Institute of Petroleum Exploration and Development College of Geosciences Yangtze University

River-dominated lacustrine deltas typically consist of multiple lobes due to autogenic lobe switching that occurs over short time scales. However, the switching patterns of multiple lobes in these deltas remain poorly understood, and the architectural features attributed to lobe switching are also lacking. By integrating Delft3D simulations, flume experiments, and modern deposit analysis, we proposed that autogenic lobe switching follows a cyclic pattern. Autocyclicity begins with the formation of an offshore lobe and concludes after a series of longshore lobe growth events, marked by longshore avulsions occurring along the sides of offshore distributary *** avulsions follow a sequence that usually occurs earlier distally than proximally and subsequently occurs on one longshore side and then on the other side. Each lobe begins with rapid growth, which gradually slows and then stops once a channel avulsion is influenced by the backwater effect that triggers lobe switching. Three signals indicate lobe switching: a decrease in progradation rate, foreset slope steepening coupled with topset slope gentling, and the deposition of mud-dominated sediments. The number of autocyclic events never exceeds *** first two autocyclicities contribute to more than 55% of delta length and 70% of delta area. The lobes are separated by 1-6 stages of mud-dominated accretion beds that exhibit a downstream-inclined shape and convexup or lateral overlapping pattern. This study conducts a coupled growth-geometric assessment to establish an architectural pattern for river-dominated lacustrine deltas. This architectural pattern offers valuable insights into predicting sandy lobe distribution in river-dominated lacustrine delta reservoirs, and the architecture of muddy accretion beds aids in predicting the rule of oil-water movement and distribution of remaining oil.

关键词： Autocyclic lobe switching River-dominated lacustrine delta Architecture Avulsion sequence Backwater effect

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2025年第1期68卷 270-296页

作者： Song XIANG Jinshui HUANG bingcheng wu School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China CAS Center of Excellence in Comparative Planetary Studies Hefei230026China

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell *** five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,*** typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and *** results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five ***,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes ***,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic ***,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate *** fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental *** the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective *** tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal *** the lithospheric strength was only 150 MPa,plate tecton

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

维普期刊数据库

在线全文

学校读者我要写书评

暂无评论

横向联邦学习:研究现状、系统应用与挑战

计算机学报 2025年第1期48卷 35-67页

作者：吴文泰吴应良林伟伟左文明暨南大学信息科学技术学院广州510632 华南理工大学电子商务系广州510006 华南理工大学计算机科学与工程学院广州510006 人工智能与数字经济广东省实验室(广州) 广州510335

随着数据和算力向网络边缘下沉,人工智能应用的研发愈加依赖隐私敏感的用户数据。在这一趋势的推动下,联邦学习因其强调隐私保护的特性而逐渐成为一个广泛应用的分布式机器学习框架。作为联邦学习的原始范式,横向联邦学习(Horizontal Fe... 详细信息

随着数据和算力向网络边缘下沉,人工智能应用的研发愈加依赖隐私敏感的用户数据。在这一趋势的推动下,联邦学习因其强调隐私保护的特性而逐渐成为一个广泛应用的分布式机器学习框架。作为联邦学习的原始范式,横向联邦学习(Horizontal Federated Learning,HFL)具有扩展能力强和使用场景广泛等特点,因此是近年来该领域的研究重心,同时在产业界相关需求的驱动下有着十分广泛的应用前景。横向联邦学习的研究涉及机器学习、分布式系统、无线通信和信息安全等多个学术领域,从研究动机到技术方法都呈现多样化,但现有文献未能展现相关研究现状的全貌。此外,横向联邦学习相关技术的发展催化出了一系列开源系统框架、公开数据集以及多种场景下的应用,对进一步研究与实践都具有参考价值。为此,本文对横向联邦学习的研究现状和系统应用进行综合性调研:首先,对相关文献按照研究目标和技术角度进行全面地分类梳理,从多领域视角分析了各分支的研究现状;其次,从应用实践的视角,对比分析了面向横向联邦学习的主流系统框架与代码库、描述了数据准备方法以及典型的应用场景。在此基础上,阐明了横向联邦学习算法研究和系统应用面临的6个关键挑战,为如何缩小相关研究与系统实践之间的鸿沟提供了新的参考。

关键词：横向联邦学习数据隐私分布式系统机器学习人工神经网络

维普期刊数据库

Oxidative degradation and upcycling of polyethylene wastes

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第2期68卷 430-443页

作者： Yizhen Che Yanfen wu Zhiqiang Niu State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Ordos Laboratory Ordos 017010China

Plastics have become omnipresent in modern life due to their versatility and ***,this convenience comes at the cost of substantial waste *** inherent chemical stability of plastics complicates its recycling,leading to environmental pollution and ecological *** mini-review highlights recent advancements in addressing this challenge by oxidative transformation of polyethylene(PE)into new functional polymers,value-added chemicals,and carbon-based *** first discuss the introduction of hydroxyl,carbonyl groups onto PE with a focus on the functionalization degree and ***,approaches for PE oxidation into dicarboxylic acids and short-chain oxidized PE are described and compared,with an emphasis on the tandem reactions for converting mixed dicarboxylic acids into other value-added *** also briefly discuss the oxidative transformation of PE into carbon-based materials and summarize the progress in qualitative and quantitative analysis of oxidation ***,we conclude this mini-review by highlighting the challenges and opportunities in the field.

关键词： oxidation polyethylene upcycling chemical conversion plastics

Dissecting the cell microenvironment of ovarian endometrioma through single-cell RNA sequencing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2025年第1期68卷 116-129页

作者： Jiangpeng wu Siyu Xia wenting Ye Yan Sun Jing Cai Fubing Yu Haiping wen Xiuwei Yi Taikang Li Mingwei Chen Jiayun Chen Ge Song Chuanbin Yang Yali Song Jigang Wang Department of Reproductive Medicine Dongguan Maternal and Child Health Care HospitalDongguan 523000China Department of Urology and Shenzhen Clinical Research Centre for GeriatricsShenzhen People’s HospitalSouthern University of Science and TechnologyShenzhen 518020China State Key Laboratory for Quality Ensurance andSustainable Use of Dao-di Herbs Artemisinin Research CenterandInstitute of Chinese Materia MedicaChina Academyof Chinese Medical SciencesBeijing 100700China State Key Laboratory of Antiviral Drugs School of PharmacyHenan UniversityKaifeng 475004China Reproductive Medicine Center Foshan Women and Children HospitalFoshan 528000China

Ovarian endometrioma(OE),also known as“chocolate cysts,”is a cystic mass that develops in the ovaries due to endometriosis and is a common gynecological condition characterized by the growth of endometrial tissue outside the uterus,leading to symptoms such as dysmenorrhea,pelvic pain,and ***,the precise molecular and cellular mechanisms driving this pathophysiology remain largely unknown,posing challenges for diagnosis and ***,we employed integrated single-cell transcriptomic profiling of over 52,000 individual cells from endometrial tissues of OE patients and healthy donors and identified twelve major cell *** identified notable alterations in cell type-specific proportions and molecular signatures associated with ***,the activation of IGFBP5^(+) macrophages with pro-inflammatory properties,NK cell exhaustion,and aberrant proliferation of IQCG^(+) and KLF2^(+) epithelium are key features and may be the potential mechanisms underlying the pathogenesis of ***,our data contribute to a better understanding of OE at the single cell level and may pave the way for the development of novel therapeutic strategies.

关键词： ovary high-throughput sequencing transcriptomics gene expression analysis ligand-receptor analysis

维普期刊数据库

Simultaneous immobilization of multiple heavy metal(loid)s in contaminated water and alkaline soil inoculated Fe/Mn oxidizing bacterium

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2025年第1期147卷 370-381页

作者： Yi wu Shengli Wang Jun Xu Fei Zang Song Long Yining wu Yuqing Wang Zhongren Nan Technology Research Center for Pollution Control and Remediation of Northwest Soil and Groundwater College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China

Two strains of Fe/Mn oxidizing bacteria tolerant to high concentrations of multiple heavy metal(loid)s and efficient decontamination for them were *** surface of the bio-Fe/Mn oxides produced by the oxidation of Fe(II)and Mn(II)by Pseudomonas taiwanensis(marked as P4)and Pseudomonas plecoglossicida(marked as G1)contains rich reactive oxygen functional groups,which play critical roles in the removal efficiency and immobilization of heavymetal(loid)s in co-contamination *** isolated strains P4 and G1 can growwell in the following environments:pH 5-9,NaCl 0-4%,and temperature 20-30℃.The removal efficiencies of Fe,Pb,As,Zn,Cd,Cu,and Mn are effective after inoculation of the strains P4 and G1 in the simulated water system(the initial concentrations of heavy metal(loid)were 1 mg/L),approximately reaching 96%,92%,85%,67%,70%,54%and 15%,*** exchangeable and carbonate bound As,Cd,Pb and Cu are more inclined to convert to the Fe-Mn oxide bound fractions in P4 and G1 treated soil,thereby reducing the phytoavailability and bioaccessible of heavy metal(loid)*** research provides alternatives method to treat water and soil containing high concentrations of multi-heavy metal(loid)s.

关键词： bio-Fe/Mn oxides Pseudomonas Heavy metal(loid)s Removal and immobilization

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Avian Research 2025年第01期 89-95页

作者： Lifang Gao wen Zhang wenjing Zhu Yichen wu Ran Xu Ningning Sun Yujie Wang biyun Jia Bo Du College of Life Sciences Northwest Normal University School of Life Sciences Lanzhou University College of Ecology Lanzhou University

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：

N^(6)-methyladenosine on the natural antisense transcript of NIA1 stabilizes its mRNA to boost NO biosynthesis and modulate stomatal movement

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2025年第1期18卷 151-165页

作者： Jie Li wen Tian Ting Chen Qing-Yan Liu Hua-Wei wu Chuan-Hui Liu Yuan-Yuan Fang Hui-Shan Guo Jian-Hua Zhao State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijingChina CAS Center for Excellence in biotic Interactions University of Chinese Academy of SciencesBeijingChina

Nitric oxide(NO)is a crucial signaling molecule that regulates a wide range of metabolic pathways in different strata of *** plants,nitrate reductase(NR)is a key enzyme for NO *** are two NR-encoding genes in Arabidopsis genome,NIA1 and NIA2,which are precisely regulated and expressed in a tissue-specific *** this study,we found that the natural antisense transcript as-NIA1,transcribed from the 30 UTR of NIA1,stabilizes NIA1 mRNA to maintain its circadian oscillation in plants grown under the light/dark ***,as-NIA1-dependent NIA1 mRNA stability is indispensable for NIA1-mediated NO biosynthesis in guard cells and natural stomatal ***,we revealed that polypyrimidine tract-binding 3(PTB3)regulates the stabilization of NIA1 mRNA by directly binding to UC-rich elements of *** further found that MTA deposits N^(6)-methyladenosine(m6 A)on as-NIA1,facilitating the as-NIA1-PTB3 interaction in vivo,in agreement with RNA structure prediction in that m6 Amediated structural alterations expose the UC-rich elements to enhance the accessibility of *** together,these findings reveal a novel molecular mechanism by which plants precisely manipulate NO biosynthesis to modulate light/dark-regulated stomatal movement,highlighting the coupling of RNA epigenetic modifications and structures shaping RNA-protein interactions in the regulation of hormone biosynthesis.

关键词： natural antisense transcript,NO biosynthesis,N^(6)-methyladenosine,NIA1,stomatal movement