检索结果-南通市图书馆

Derivatives of Intersection Local Time for Two Independent Symmetricα-stable Processes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第5期40卷 1273-1292页

作者： huan.ZHOU Guang Jun SHEN Qian yu Department of Mathematics Anhui Normal UniversityWuhu 241002P.R.China Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Key Laboratory of Mathematical Modelling and High Performance Computing of Air Vehicles(NUAA) MIITNanjing 211106P.R.China

In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient condition for the existence of the derivatives,which makes us obtain the exponential integrability and H?lder *** we show that this condition is also necessary for the existence of derivatives of intersection local time at the ***,we also study the power variation of the derivatives.

关键词： Symmetric stable processes intersection local time exponential integrability power variation

Large isolated fibrous tumors in the upper esophagus: A case report

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

World Journal of Gastrointestinal Oncology 2024年第2期16卷 543-549页

作者： Jia-Jia yu huan.Shuan. Pei yu Meng Department of Anesthesiology The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Solitary fibrous tumors(SFT)are rare spindle cell tumors that are usually benign.A total of 10 cases of SFTs in the upper esophagus have ever been ***,we report the anesthetic management of a patient with a large isolated fibrous tumor of the upper esophagus compressing the tracheal *** also provide a literature review of the current *** SUMMARY We report the case of a 49 year old male with“cough aggravation and wheezing after exercise”,who underwent esophagectomy for a large isolated fibrous tumor compressing the tracheal membrane in the upper *** advise the use of a single-lumen tube with a blocker in patients with difficult airways to reduce the incidence of airway injury and fibrinoscopy at all stages of the perioperative period to guide airway *** case study is the first report of the anesthetic management of a large,isolated fibrous tumor compressing the tracheal membrane in the upper *** This rare case emphasizes the importance of perioperative management of anesthesia in patients with large isolated fibrous tumors of the upper esophagus that compress the tracheal *** use of blocker reduce the incidence of airway injury and fibrinoscopy at the perioperative period to guide airway mana-gement.

关键词： Upper esophagus Isolated fibrous tumor Tracheal membrane Peak airway pressure Case report

Embracing digital mindsets to ensure a sustainable future

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第3期18卷 177-179页

作者： Chengjun Li Riqing yu Wenjing Ning huan.Zhong Christian Sonne Institute of Environmental Research at Greater Bay Area Guangzhou UniversityGuangzhou 510000China Department of Biology Center for EnvironmentBiodiversity and ConservationThe University of Texas at TylerTylerTX 75701USA School of Environment Nanjing UniversityNanjing 210000China Environmental and Life Science Program Trent UniversityPeterboroughOntarioK9H 0A1Canada Faculty of Science and Technology Aarhus UniversityRoskildeDenmark 4000The Kingdom of Denmark Sustainability Cluster School of EngineeringUniversity of Petroleum&Energy StudiesDehradunUttarakhand 248001India

The 19th Asian Games astounded global audiences with an opening spectacle that showcased stunning digital fireworks(International Olympic Committee,2021;Zhe,2023).The groundbreaking display was brought to life through virtual reality(VR)and augmented reality(AR)*** sets a pioneering example to replace conventional fireworks in major international events as well as in other large-scale entertainment activities,marking a historic milestone in the pursuit of a sustainable and healthy future.

关键词： Wildlife Climate Change Heavy metals Noise LAN Light pollution

Outer-surface Covering of Nanochannels with Hydrogel for Highly Sensitive and Specific Cr(VI)Detection Through Analyte-caused Charge Change in Hydrogel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第2期40卷 326-332页

作者： LIU huan.SUN Xueting DAI yu ZHANG Xiaojin XIA Fan Faculty of Materials Science and Chemistry China University of GeosciencesWuhan430074P.R.China

Nanochannels have made great progress and are a promising platform for detecting a series of ***,most nanochannels are modified on the inner wall,while ignoring the outer ***,we modified the outer surface of nanochannels with *** from other reported outer-surface modification methods,we directly cover nanochannels with hydrogel to form heterogeneous *** selected hydrogel hardly adsorbs other ions and shows specific adsorption for Cr(VI).The adsorption sites in hydrogel are homogeneous,and Cr(VI)adsorption onto hydrogel is endothermic and *** charge in hydrogel changes after Cr(VI)adsorption,and the resulting current changes can be used for the detection of Cr(VI)with the detection limit of 10−11 mol/*** platform is expected to be used for Cr(VI)detection in living organisms,especially within *** work provides a new approach for outer-surface modification of nanochannels and offers a new choice for nanochannel detection platforms.

关键词： Nanochannel Hydrogel Heterogeneous membrane Cr(VI)detection

A regression approach for seismic first-break picking

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2024年第3期21卷 1584-1596页

作者： huan.yuan San-Yi yuan Jie Wu Wen-Jing Sang yu-He Zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

Deliberate self-harm among pediatric psychiatric inpatients in China:A single-center retrospective study

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

World Journal of Psychiatry 2024年第3期14卷 398-408页

作者： Xing-Zhi Jiang huan.huan.Li Zhen-Zhen yu Chen Wang Department of Child and Adolescent Psychiatry Shenzhen Kangning HospitalShenzhen Mental Health CenterShenzhen Key Laboratory for Psychological Healthcare and Shenzhen Institute of Mental HealthShenzhen 518020Guangdong ProvinceChina Department of Psychiatry Xiamen Xianyue HospitalXiamen 361012Fujian ProvinceChina Department of Geriatric Medicine Dalian Medical UniversityDalian 116000Liaoning ProvinceChina Department of Neurology The Second Affiliated Hospital of Xiamen Medical CollegeXiamen 361000Fujian ProvinceChina Department of Neurology and Department of Neuroscience The First Affiliated Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina

BACKGROUND For children and adolescents,deliberate self-harm(DSH)is becoming a mental health problem of *** several studies on the prevalence and factors of DSH in the world,there is little information on DSH among children and adolescents in *** study explores the prevalence,types,associated risk factors and tendency of DSH in pediatric psychiatric inpatients in *** To understand the situation of DSH among hospitalized children and adolescents and its related *** In this study,we retrospectively studied 1414 hospitalized children and adolescents with mental illness at Xiamen Mental Health Center from 2014 to 2019,extracted the demographic and clinical data of all patients,and analyzed clinical risk factors of *** A total of 239(16.90%)patients engaged in at least one type of DSH in our ***(n=115,48.12%)was the most common type of ***(n=171,71.55%)were more likely to engage in DSH than males(n=68,28.45%).DSH was positively associated with depressive disorders[OR=3.845(2.196-6.732);P<0.01],female[OR=2.536(1.815-3.542);P<0.01],parental marital status[OR=5.387(2.254-12.875);P<0.01]and negative family history of psychiatric illness[OR=7.767(2.952-20.433);P<0.01],but not with occupation,substance use and history of physical *** Our findings suggest that for patients with depression,females,an abnormal marriage of parents,and no history of mental illness,attention should be paid to the occurrence of DSH.

关键词： Deliberate self-harm Children Adolescent Psychiatric inpatients Retrospective study

Impact of Polymer Matrix on Polymer Mechanochromism from Excited State Intramolecular Proton Transfer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第6期42卷 611-616页

作者： yu Wu Xin Cheng huan.Hu Shui Hu Zhimin Ma Zhiyong Ma Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing100029 China Center of Advanced Elastomer Materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China College of Engineering Peking UniversityBeijing100871 China

Mechanochromic polymers based on non-covalent changes have attracted much attention ***,we report the impact of inter/intramolecular hydrogen bonds on polymer mechanochromism from the excited state intramolecular proton transfer (ESIPT) ***-NH2-OH and PhMz=2A are designed and obtained by simple and high-yield synthesis,and are connected into polyurethane and poly(methyl acrylate-co-2-ethylhexyl acrylate),*** the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hydrogen bonds that interrupt the ESIPT reactions but the PhMz=2A@PMA-2-EA sample expresses cyan fluorescence belonging to the excited keto form (K*) emission,implying that the intramolecular hydrogen bonds ***,under stretching,external force can tune the emission of the PhMz=2A@PMA-2-EA sample from K* to E* *** external force can putatively still promote a bond rotation,ESIPT reactions remain equivalently interrupted in both the relaxed and stressed states in a hydrogen-bond donating *** calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/***,PhMz-NH2-OH@PU and PhMz=2A@PMA-2-EA showed disparate initial ESIPT states and further different responses/sensitivity to *** study reports a novel and efficient strategy for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Polymer mechanochromism Excited state intramolecular proton transfer Hydrogen bonding Supramolecular chemistry Elastomers

Experimental Study on Towing Characteristics of Composite Bucket Wellhead Platform

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第3期38卷 531-542页

作者： ZHANG Pu-yang LIU Ying-fei LE Cong-huan.DING Hong-yan BAI yu State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China

With the rapid development of large-scale development of marginal oilfields in China,simple wellhead platforms that are simple in structure and easy to install have become an inevitable choice in the process of oilfield ***,traditional simple wellhead platforms are often discarded after a single *** pursuit of a more costeffective approach to developing marginal oilfields,this paper proposes a new offshore oil field development facility—an integrated bucket foundation for wellhead *** verify the safety of its towing behavior and obtain the dynamic response characteristics of the structure,this paper takes a bucket integrated bucket foundation for wellhead platform with a diameter of 40 m as the research *** combining physical model tests and numerical simulations,it analyzes the static stability and dynamic response characteristics of the structure during towing,complete with the effects of the draft,wave height,wave period,and towing point height,which produce the dynamic responses of the structure under different influence factors,such as roll angle,pitch angle,heave acceleration and towing force as well as the sensibility to transport *** results show that the integrated bucket foundation for wellhead platform is capable of self-floating towing,and its movement is affected by the local environment,which will provide a reference for actual projects.

关键词： composite bucket foundation wellhead platform air flotation towing model test

Regulating Oxygen Vacancy Defects in Heterogeneous NiO-CeO_(2)−δ Hollow Multi-shelled Structure for Boosting Oxygen Evolution Reaction

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

Chemical Research in Chinese Universities 2024年第3期40卷 475-483页

作者： WANG huan.GONG Guannan SUN Guohua QI Jian yu Ranbo WANG Dan Hebei Key Laboratory of Flexible Functionals Materials School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang 050000P.R.China Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science&Technology BejingBeijing 100083P.R.China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China

CeO_(2) with excellent oxygen storage-exchange capacity and NiO with excellent surface activity were used to construct a heterogeneous NiO-CeO_(2)−δhollow multi-shelled structure(HoMS)by spray *** turned out that as the proportion of CeO_(2) increases,the overpotential and Tafel slope of NiO-CeO_(2)−δHoMSs first decreased and then *** is mainly because the construction of the NiO-CeO_(2)−δHoMSs not only increases the specific surface area,but also introduces oxygen vacancy defects,thus improving the interface charge transfer capability of the materials and further improving the oxygen evolution reaction(OER)***,the increase of the calcination temperature will induce the decay of the OER performance of NiO-CeO_(2)−δHoMSs,which is mainly due to the decrease of the specific surface area,the reduction of oxygen vacancy defects,and the weakening of interface charge transfer ***,a series of heterogeneous composite HoMSs,such as Ni/Co,Mo/Ni,Al/Ni and Fe/Ni oxides was successfully constructed by spray drying,which enriched the diversity of HoMSs.

关键词： Heterogeneous composite structure Hollow multishelled structure Oxygen vacancy defect Oxygen evolution reaction