检索结果-南通市图书馆

Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

引用

Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying Wang Shengling Si Hongli Li david da yong chen National Institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Si Chuan Zhong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment *** effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of *** affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were *** optimum conditions were found to be 120℃,10 min,and 3 cycles,***-MS/MS method was developed to obtain the optimal sensitivity specific to *** method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/*** ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent *** optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target ***,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to *** is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressurized liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control

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

SHEL:a semantically enhanced hardware-friendly entity linking method

引用

High Technology Letters 2024年第1期30卷 13-22页

作者：亓东林 chen Shudong DU Rong TONG da YU yong Institute of Microelectronics of Chinese Academy of Sciences Beijing 100029P.R.China University of Chinese Academy of Sciences Beijing 100190P.R.China

With the help of pre-trained language models,the accuracy of the entity linking task has made great strides in recent ***,most models with excellent performance require fine-tuning on a large amount of training data using large pre-trained language models,which is a hardware threshold to accomplish this *** researchers have achieved competitive results with less training data through ingenious methods,such as utilizing information provided by the named entity recognition *** paper presents a novel semantic-enhancement-based entity linking approach,named semantically enhanced hardware-friendly entity linking(SHEL),which is designed to be hardware friendly and efficient while maintaining good ***,SHEL's semantic enhancement approach consists of three aspects:(1)semantic compression of entity descriptions using a text summarization model;(2)maximizing the capture of mention contexts using asymmetric heuristics;(3)calculating a fixed size mention representation through pooling *** series of semantic enhancement methods effectively improve the model's ability to capture semantic information while taking into account the hardware constraints,and significantly improve the model's convergence speed by more than 50%compared with the strong baseline model proposed in this *** terms of performance,SHEL is comparable to the previous method,with superior performance on six well-established datasets,even though SHEL is trained using a smaller pre-trained language model as the encoder.

关键词： entity linking(EL) pre-trained models knowledge graph text summarization semantic enhancement

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

Hyperbolic hierarchical graph attention network for knowledge graph completion

引用

High Technology Letters 2024年第3期30卷 271-279页

作者： XU Hao chen Shudong QI Donglin TONG da YU yong chen Shuai Institute of Microelectronics of Chinese Academy of Sciences Beijing 100029P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Utilizing graph neural networks for knowledge embedding to accomplish the task of knowledge graph completion(KGC)has become an important research area in knowledge graph ***,the number of nodes in the knowledge graph increases exponentially with the depth of the tree,whereas the distances of nodes in Euclidean space are second-order polynomial distances,whereby knowledge embedding using graph neural networks in Euclidean space will not represent the distances between nodes *** paper introduces a novel approach called hyperbolic hierarchical graph attention network(H2GAT)to rectify this ***,the paper conducts knowledge representation in the hyperbolic space,effectively mitigating the issue of exponential growth of nodes with tree depth and consequent information ***,it introduces a hierarchical graph atten-tion mechanism specifically designed for the hyperbolic space,allowing for enhanced capture of the network structure inherent in the knowledge ***,the efficacy of the proposed H2GAT model is evaluated on benchmark datasets,namely WN18RR and FB15K-237,thereby validating its *** H2GAT model achieved 0.445,0.515,and 0.586 in the Hits@1,Hits@3 and Hits@10 metrics respectively on the WN18RR dataset and 0.243,0.367 and 0.518 on the FB15K-237 *** incorporating hyperbolic space embedding and hierarchical graph attention,the H2GAT model successfully addresses the limitations of existing hyperbolic knowledge embedding models,exhibiting its competence in knowledge graph completion tasks.

关键词： hyperbolic space link prediction knowledge graph embedding knowledge graph completion(KGC)

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

Geometric prior guided hybrid deep neural network for facial beauty analysis

引用

CAAI Transactions on Intelligence Technology 2024年第2期9卷 467-480页

作者： Tianhao Peng Mu Li Fangmei chen yong Xu david Zhang The School of Computer Science and Technology Guizhou UniversityGuiyangChina Department of Automation Moutai InstituteRenhuaiGuizhouChina The School of Computer Science and Technology Harbin Institute of TechnologyShenzhenShenzhenChina The Information and Communication Engineering Department Dalian Minzu UniversityDalianChina The School of data Science The Chinese University of Hong KongShenzhenShenzhenChina

Facial beauty analysis is an important topic in human *** may be used as a guidance for face beautification applications such as cosmetic *** neural networks(DNNs)have recently been adopted for facial beauty analysis and have achieved remarkable ***,most existing DNN-based models regard facial beauty analysis as a normal classification *** ignore important prior knowledge in traditional machine learning models which illustrate the significant contribution of the geometric features in facial beauty *** be specific,landmarks of the whole face and facial organs are introduced to extract geometric features to make the *** by this,we introduce a novel dual-branch network for facial beauty analysis:one branch takes the Swin Transformer as the backbone to model the full face and global patterns,and another branch focuses on the masked facial organs with the residual network to model the local patterns of certain facial ***,the designed multi-scale feature fusion module can further facilitate our network to learn complementary semantic information between the two *** model optimisation,we propose a hybrid loss function,where especially geometric regulation is introduced by regressing the facial landmarks and it can force the extracted features to convey facial geometric *** performed on the SCUT-FBP5500 dataset and the SCUT-FBP dataset demonstrate that our model outperforms the state-of-the-art convolutional neural networks models,which proves the effectiveness of the proposed geometric regularisation and dual-branch structure with the hybrid *** the best of our knowledge,this is the first study to introduce a Vision Transformer into the facial beauty analysis task.

关键词： deep neural networks face analysis face biometrics image analysis

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

Improving link prediction models through a performance enhancement scheme:a study on semi-supervised learning and model soup

引用

The Journal of China Universities of Posts and Telecommunications 2024年第4期31卷 43-53页

作者： Qi Donglin chen Shudong Du Rong Yu yong Tong da Intelligent Manufacturing Electronics Research and Development Center Institute of Microelectronics of the Chinese Academy of SciencesBeijing 100029China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100049China

As an important method for knowledge graph(KG)complementation,link prediction has become a hot research topic in recent *** this paper,a performance enhancement scheme for link prediction models based on the idea of semi-supervised learning and model soup is proposed,which effectively improves the model performance on several mainstream link prediction models with small changes to their *** novel scheme consists of two main parts,one is predicting potential fact triples in the graph with semi-supervised learning strategies,the other is creatively combining semi-supervised learning and model soup to further improve the final model performance without adding significant computational *** validate the effectiveness of the scheme for a variety of link prediction models,especially on the dataset with dense *** terms of CompGCN,the model with the best overall performance among the tested models improves its Hits@1 metric by 14.7%on the FB15K-237 dataset and 7.8%on the WN18RR dataset after using the enhancement ***,it is observed that the semi-supervised learning strategy in the augmentation scheme has a significant improvement for multi-class link prediction models,and the performance improvement brought by the introduction of the model soup is related to the specific tested models,as the performances of some models are improved while others remain largely unaffected.

关键词： natural language processing knowledge graph(KG) link prediction model soup semi-supervised learning

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

In situ crosslink polymerization induced long-lived multicolor supramolecular hydrogel based on modifiedβ-cyclodextrin

引用

Chinese Chemical Letters 2024年第2期35卷 374-379页

作者： yonghui Sun Linnan Jiang yong chen Yu Liu College of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

The construction of hydrogels with good mechanical properties and phosphorescent properties is full of ***,we report a supramolecular phosphorescent hydrogel with long lifetime,high tensile strength and self-healing property,which can be easily constructed through in-situ thermalinitiated polymerization of isocyanatoethyl acrylate-modifiedβ-cyclodextrin(β-CD-da)and acrylatemodified adamantane(Ad-da),acrylic acid(AA),followed by the non-covalent association with carbon dots(CNDs).The lifetime of phosphorescent hydrogel can reach 1261 ms at room temperature,and the quantum yield is 11%.Importantly,through the efficient triplet to singlet Förster resonance energy transfer(TS-FRET),the phosphorescent hydrogel shows the good phosphorescence energy transfer property for organic dyes Rhodamine B and Eosin Y with the delayed fluorescence lifetime up to 730 ms and 585 ms as well as the energy transfer efficiency(Φ_(ET))up to 99.9%and 99.3%,***,owing to the host-guest interactions betweenβ-CD-da and Ad-da,the three-dimensional cross-linked network phosphorescent hydrogel can be easily stretched to 18 times of its original length,and can achieve self-healing of the cut surfaces within 30 *** results will expand the scope of phosphorescent materials and provide new ideas and opportunities for materials science.

关键词： Room temperature phosphorescence Hydrogel Phosphorescence energy transfer Cyclodextrin Supramolecular interaction

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

Clinical characteristics of sudden hearing loss during pregnancy

引用

世界耳鼻咽喉头颈外科杂志英文版 2024年第3期10卷 165-172页

作者： Wu Xiao-Nan Wang Hong-Yang Zhang Xiao-Long chen Guo-Hui Guan Jing Gao Yun Wang da-yong Wang Qiu-Ju Senior Department of Otolaryngology-Head & Neck Surgery The Sixth Medical Center of PLA General Hospital Chinese PLA Medical School Beijing China National Clinical Research Center for Otolaryngologic Diseases Beijing China

Objective: The objective of this study was to explore the clinical characteristics and management of sudden hearing loss (HL) during pregnancy, thus better guiding the clinical ***: The clinical and follow-up data of 17 patients (17 ears) with sudden HL during pregnancy were analyzed retrospectively (the observe group). Twelve nonpregnant female patients (12 ears) with sudden HL of similar clinical characteristics were selected as the control group. The prognosis of the two groups was compared. All the patients were followed up after delivery, and two of them were readmitted to the hospital 1–2 months after ***: The observe group had better improvement in hearing and a higher response rate compared to the control group. The pure tone hearing and speech recognition rate of patients could still be improved after the readmitted treatment, and the hearing could partially recover spontaneously during follow-up. The laboratory indicators that affect the inflammatory response and coagulation pathway were significantly different between the two ***: The hearing condition of sudden HL during pregnancy is severe, and the prognosis of these patients is better than nonpregnant patients of similar clinical characteristics. Postpartum treatment is still effective, and some patients showed self-healing with time during follow-up. The inflammatory response and coagulation function may affect the hearing of patients through a metabolic pathway.

关键词： management pregnancy prognosis sudden hearing loss

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

Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

引用

Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang yong-Qing Liu Qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang da-Wei Qiao Xiao-Shuai chen Li-Zhi Wu Meng Tian Long chen Yi Wei Liao-Yuan Song Jian Li Zi-Gang Wu Yun-Qian Liu Xuan-Chun Liu An-Qing chen Zhi-Wei Liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

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

高效球磨法萃取天然产物

高效球磨法萃取天然产物

引用

第21届全国色谱学术报告会及仪器展览会

作者：汪曼毕文韬杨小弟 david da yong chen 江苏省生物医学功能材料协同创新中心江苏省生物化学材料重点实验室化学与材料科学学院南京师范大学英属哥伦比亚大学化学学院

＜正＞正文:球磨法作为一种机械处理方法,目前已被用于多种材料的外部改性和纤维素的破坏[1, 2]。因此,球磨法是一种特殊的、优秀的萃取方法,它可以通过研磨珠的多角度、同步的撞击样品来破坏细胞从而释放出其中的活性成分到萃取溶剂中... 详细信息

＜正＞正文:球磨法作为一种机械处理方法,目前已被用于多种材料的外部改性和纤维素的破坏[1, 2]。因此,球磨法是一种特殊的、优秀的萃取方法,它可以通过研磨珠的多角度、同步的撞击样品来破坏细胞从而释放出其中的活性成分到萃取溶剂中[3]。与其他萃取方法相比,球磨法缩短了萃取所需时间,提高了萃取率,大大减少了溶剂的消耗,并且避免了噪音和辐射污染[4]。由于以上优点,球磨法被认为是一种绿色的萃取方法。由此我们建立了一种可以从植物中温和地提取出其中可溶性成

关键词：球磨辅助机械力化学萃取离子液体天然产物样品分离

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3 eV to 20 MeV on the Back-n at CSNS

引用

Nuclear Science and Techniques 2024年第2期35卷 85-93页

作者： Jie-Ming Xue Song Feng yong-Hao chen Han Yi Min Xiao Pin-Jing cheng Xin-Xiang Li Rong Liu Yi-Wei Yang Zi-Jie Han da-Jun Zhao Hao-Qiang Wang Bao-Qian Li Ji-Rong Zhao Lei-Xun Tang Wen Luo Bo Zheng School of Nuclear Science and Technology University of South ChinaHengyang 421001China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron *** energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick high-purity natural lead sample was employed for the neutron transmission *** on-beam background was determined using Co,In,Ag,and Cd *** excitation function of ^(nat)Pb(n,tot)reaction below 20 MeV was calculated using the TALYS-1.96 nuclear-reaction modeling *** present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3,JENDL-5,CENDL-3.2,and BROND-3.1),and the theoretical calculation *** agreement was found between the new results and those of previous experiments and with the theoretical curves in the corresponding *** measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy *** provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead.

关键词： Neutron-induced total cross section Natural lead Time-of-flight TALYS-1.96 CSNS Back-n white neutron beamline

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：