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盐下地质的地球物理成像法

国外油气勘探 1998年第1期10卷 85-95页

作者： Davis W.Ratcliff david j.weber 郝顺元物探局研究院信息中心

约在四年前,关于墨西哥湾海上勘探给人的总的感觉是:勘探工作主要是在大陆架进行,而且已经做完了,并在继续减少。由于技术和经验的限制,多数人认为深水域风险太大,因此,只有很少量的重点区域还保留着。实际上,大部分公司都从墨西哥湾撤... 详细信息

约在四年前,关于墨西哥湾海上勘探给人的总的感觉是:勘探工作主要是在大陆架进行,而且已经做完了,并在继续减少。由于技术和经验的限制,多数人认为深水域风险太大,因此,只有很少量的重点区域还保留着。实际上,大部分公司都从墨西哥湾撤退出来了。后来,在1993年10月,由于Mahogany盐床的发现,仿佛一夜之间改变了这种情况,并且点燃了渴望有新发现的那些人的希望,看来光明就在前头。

关键词：盐构造下部地球物理勘探成像方法

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Mahogany盐床上的盐下成像

国外油气勘探 1997年第4期9卷 485-487页

作者： Davis W.Ratcliff david j.weber 席小燕王皖生石油地球物理勘探局第一地质调查处科技科

盐下油气勘探一直是并将继续成为一项具有高风险和高商业潜力的工作。最近,在墨西哥湾以及世界其他盆地中(发现的)盐下油气显示使得人们对盐下勘探产生了极大的兴趣。在成功的盐下勘探中,起着重要作用的地球物理技术最主要的是深度偏移... 详细信息

盐下油气勘探一直是并将继续成为一项具有高风险和高商业潜力的工作。最近,在墨西哥湾以及世界其他盆地中(发现的)盐下油气显示使得人们对盐下勘探产生了极大的兴趣。在成功的盐下勘探中,起着重要作用的地球物理技术最主要的是深度偏移。深度偏移技术(叠后和叠前)可以使勘探工作者识别和绘制圈闭重要烃类聚集的盐下构造图和地层特征。在本文中,我们用Mahogany盐床地区作为样板,讨论盐下成像方法和技术应用(三维时间和深度偏移),它可以有助于盐下勘探工作者进行远景评估、风险判断。

关键词：三维地震勘探盐膏层成像叠前偏移深度偏移

Dissociation cross sections ofψ(3770),ψ(4040),ψ(4160),andψ(4415)mesons with nucleons

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Communications in Theoretical Physics 2024年第4期76卷 93-112页

作者： Ruo-Qing Ding Xiao-Ming Xu H j.weber Department of Physics Shanghai UniversityBaoshanShanghai 200444China Department of Physics University of VirginiaCharlottesvilleVA 22904United States of America

We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a ■ meson leads to the dissociation of the ■ meson. We consider the reactions:■, and■, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and the ■ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the S-matrix *** cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-charmonium scattering quark interchange relativistic constituent quark potential model

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： david j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Enhancing diabetic retinopathy screening:Non-mydriatic fundus photography-assisted telemedicine for improved clinical management

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World journal of Diabetes 2024年第8期15卷 1820-1823页

作者： Kira j Szulborski david j Ramsey Department of Ophthalmology Tufts University School of MedicineBostonMA 02111United States Lahey Department of Surgery Division of OphthalmologyUMass Chan Medical SchoolUniversity of MassachusettsBurlingtonMA 01805United States Graduate Faculty New England College of OptometryBostonMA 02115United States

The utilization of non-mydriatic fundus photography-assisted telemedicine to screen patients with diabetes mellitus for diabetic retinopathy provides an accurate,efficient,and cost-effective method to improve early detection of *** has also been shown to correlate with increased participation of patients in other aspects of diabetes *** particular,patients who undergo teleretinal imaging are more likely to meet Comprehensive Diabetes Care Healthcare Effectiveness Data and Information Set metrics,which are linked to preservation of quality-adjusted life years and additional downstream healthcare savings.

关键词： Diabetes Diabetic retinopathy Telemedicine Tele-ophthalmology Nonmydriatic fundus photography-assisted telemedicine Vision screening Preventative health services Health policy

Charged particles:Unique tools to study irradiation resistance of concentrated solid solution alloys

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journal of Materials Science & Technology 2023年第9期140卷 260-276页

作者： Yanwen Zhang Lumin Wang William j.weber Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN37831USA Department of Materials Science&Engineering University of TennesseeKnoxvilleTN37996USA Department of Nuclear Engineering and Radiological Sciences University of MichiganAnn ArborMI48109USA

Many multicomponent concentrated solid solution alloys(CSAs),including high-entropy alloys(HEAs),exhibit improved radiation resistance and enhanced structural stability in harsh *** study and assess irradiation resistance of nuclear materials,energetic ion and electron beams are commonly used to create displacement ***,charged particles of ions,electrons,and positrons are unique tools to create and characterize radiation *** beam analysis(e.g.,Rutherford backscattering spectrometry,nuclear reaction analysis,and time-of-flight elastic recoil detection analysis),electron microscopy techniques(e.g.,transmission or scanning electron microscopy,and electron diffraction),and positron annihilation spectroscopy have been applied to characterize irradiated CSAs or HEAs to understand defect formation and evolution together with chemical and microstructural *** distinctive analyzing power and some perspectives in these techniques are *** developing structural alloys desirable for applications in advanced reactors,neutron exposure is a critical test but the limitation in achievable high damage levels is,however,a *** irradiation is often used as a surrogate for neutron irradiation,and the associated reduced transmutations and higher displacements per atom(dpa)rates are desirable for materials ***,cautions need to be taken when relying on ion irradiation results for reactor *** on differences between ions and neutrons is briefly *** addition,the links to bridge the current advances on fundamental understandings to reactor applications are discussed to lay the groundwork between neutrons and ions for radiation effects studies.

关键词： chemical disorder high-entropy alloys chemically complex alloys charged particles radiation resistance displacement damage electronic energy loss and ionization transmutation

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.j.Kucernak david Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Oryza CLIMtools:A genome–environment association resource reveals adaptive roles for heterotrimeric G proteins in the regulation of rice agronomic traits

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Plant Communications 2024年第4期5卷 145-165页

作者： Angel Ferrero-Serrano david Chakravorty Kobie j.Kirven Sarah M.Assmann Biology Department Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA Intercollege Graduate Degree Program in Bioinformatics and Genomics Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA

Modern crop varieties display a degree of mismatch between their current distributions and the suitability of the local climate for their *** address this issue,we present Oryza CLIMtools(https://***/CLIMtools/oryza_v1.0/),thefirst resource for pan-genome prediction of climate-associated genetic variants in a crop *** CLIMtools consists of interactive web-based databases that enable the user to(1)explore the local environments of traditional rice varieties(landraces)in South-East Asia and(2)investigate the environment by genome associations for 658 Indica and 283 japonica rice landrace accessions collected from georeferenced local environments and included in the 3K Rice Ge-nomes *** demonstrate the value of these resources by identifying an interplay betweenflowering time and temperature in the local environment that is facilitated by adaptive natural variation in OsHD2 and disrupted by a natural variant in *** quantitative trait locus analysis has suggested the impor-tance of heterotrimeric G proteins in the control of agronomic ***,we analyzed the climate associations of natural variants in the different heterotrimeric G protein *** identified a coordi-nated role of G proteins in adaptation to the prevailing potential evapotranspiration gradient and revealed their regulation of key agronomic traits,including plant height and seed and panicle *** conclude by highlighting the prospect of targeting heterotrimeric G proteins to produce climate-resilient crops.

关键词： Oryza sativa rice G by E adaptation flowering time GWAS OsHD2 OsSOC1 heterotrimeric G pro-tein OsRGA1 d1 OsGS3 OsDEP1 OsGGC2

Integrating petrophysical data into efficient iterative cluster analysis for electrofacies identification in clastic reservoirs

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Energy Geoscience

Energy Geoscience 2024年第4期5卷 291-305页

作者： Mohammed A.Abbas Watheq j.Al-Mudhafar Aqsa Anees david A.Wood Basrah Oil Company BasrahIraq Institute of International Rivers and Eco-Security Yunnan UniversityKunming650500China Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming650500China DWA Energy Limited LincolnUK

Efficient iterative unsupervised machine learning involving probabilistic clustering analysis with the expectation-maximization(EM)clustering algorithm is applied to categorize reservoir facies by exploiting latent and observable well-log variables from a clastic reservoir in the Majnoon oilfield,southern *** observable well-log variables consist of conventional open-hole,well-log data and the computer-processed interpretation of gamma rays,bulk density,neutron porosity,compressional sonic,deep resistivity,shale volume,total porosity,and water saturation,from three wells located in the Nahr Umr *** latent variables include shale volume and water *** EM algorithm efficiently characterizes electrofacies through iterative machine learning to identify the local maximum likelihood estimates(MLE)of the observable and latent variables in the studied *** optimized EM model developed successfully predicts the core-derived facies classification in two of the studied *** EM model clusters the data into three distinctive reservoir electrofacies(F1,F2,and F3).F1 represents a gas-bearing electrofacies with low shale volume(Vsh)and water saturation(Sw)and high porosity and permeability values identifying it as an attractive reservoir *** results of the EM model are validated using nuclear magnetic resonance(NMR)data from the third studied well for which no cores were *** NMR results confirm the effectiveness and accuracy of the EM model in predicting *** utilization of the EM algorithm for electrofacies classification/cluster analysis is ***,the clusters it establishes are less rigidly constrained than those derived from the more commonly used K-means clustering *** EM methodology developed generates dependable electrofacies estimates in the studied reservoir intervals where core samples are not ***,once calibrated with core data in some wells,the model is suitable for

关键词： Cluster analysis Electrofacies classification Expectation-maximization(EM)algorithm Clastic reservoir Maximum likelihood estimate(MLE)