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Isla San Pedro Nolasco as a late miocene intrusive record at the eastern margin of the Gulf of California:Insights from geological,geochemical and geochronological studies

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Geoscience Frontiers 2022年第3期13卷 100-114页

作者： l.A.Velderrain-Rojas J.R.Vidal-Solano l.m.Alva-Valdivia R.Vega-Granillo m.lópez-martinez Departamento de Geología División de Ciencias Exactas y NaturalesUniversidad de SonoraC.P.83000 HermosilloSonoraMexico laboratorio de Paleomagnetismo Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación CientíficaC.P.04510 MéxicoD.F.Mexico Departamento de Geología División de Ciencias de la TierraCentro de Investigación Científica y de Educación Superior de EnsenadaBaja CaliforniaMexico

Isla San Pedro Nolasco(ISPN)is a structural high bounded by inactive dextral oblique-slip faults in the east-central part of the Gulf of California rift zone and is composed of intrusive rocks not exposed on other Gulf of California *** we present the reconnaissance results from geological mapping,as well as first geochemical and geochronological data for the ISPN intrusive *** intrusive rocks compose a sheet-like body of intermediate and felsic composition intruded by an intermediate and acidic dike *** intrusive rocks(host and dikes)range in age from ca.9 ma to 10 ma(^(40)Ar/^(39)Ar)and show a hydrous ferromagnesian mineral association(amphibole and biotite)with a calc-alkalic and transitional *** hydrated mineralogical association has not been recognized in the coeval rocks along the onshore western margin of the North American plate(coastal Sonora).However,such hydrous mineralogical association is found in the coeval rift transitional volcanic rocks from the Baja California microplate at Santa Rosalía and Bahía de losÁngeles–Bahía de lasÁ*** ISPN continental block,at least 40 km long,has been pulled apart by transtensional faulting of the late miocene Gulf of California shear zone before the westward migration of the North America-Pacific plate boundary at ca.3–2 ***,ISPN became isolated as an island during the late miocene flooding of the Gulf of California seaway.

关键词： PAC-NAm plate boundary Gulf of California Intrusive rocks Isla San Pedro Nolasco

Stair and Step Soliton Solutions of the Integrable (2+1) and (3+1)-Dimensional Boiti-leon-manna-Pempinelli Equations

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Communications in Theoretical Physics 2012年第12期58卷 785-794页

作者： m.T. Darvishi m. Najafi l. Kavitha m. Venkatesh Department of mathematics Razi University Department of Physiology Faculty of Medicine Kermanshah University of Medical Sciences Department of Physics Periyar University Center for Nanoscience and Nanotechnology Periyar University

The multiple exp-function method is a new approach to obtain multiple wave solutions of nonlinear partial differential equations (NlPDEs). By this method one can obtain multi-soliton solutions of NlPDEs. In this paper, using computer algebra systems, we apply the multiple exp-function method to construct the exact multiple wave solutions of a (2+1)-dimensional Boiti-leon-manna-Pempinelli equation. Also, we extend the equation to a (3+1)-dimensional case and obtain some exact solutions for the new equation by applying the multiple exp-function method. By these applications, we obtain single-wave, double-wave and multi-wave solutions for these equations.

关键词： multiple exp-function method Boiti-leon-manna-Pempinelli equation exact solution multi-soliton solution

Physics design of 14 meV neutron generator facility at the Institute for Plasma Research

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Plasma Science and Technology 2023年第12期25卷 115-121页

作者： H l SWAmI S VAlA m RAJPUT m ABHANGI Ratnesh KUmAR A SAXENA Rajesh KUmAR Institute for Plasma Research Gandhinagar 382428India Homi Bhabha National Institute Training School ComplexMumbai 400094India

A high energy and high yield neutron source is a prime requirement for technological studies related to fusion reactor development. It provides a high-energy neutron environment for small-scale fusion reactor components research and testing such as tritium breeding, shielding, plasmafacing materials, reaction cross-section data study for fusion materials, etc. Along with ITER participation, the Institute of Plasma Research, India is developing an accelerator-based 14 meV neutron source with a yield of 10^(12)n s^(-1). The design of the source is based on the deuterium–tritium fusion reaction. The deuterium beam is accelerated and delivered to the tritium target to generate 14 meV neutrons. The deuterium beam energy and tritium availability in the tritium target are the base parameters of the accelerator-based neutron source design. The paper gives the physics design of the neutron generator facility of the Institute for Plasma Research. It covers the requirements, design basis, and physics parameters of the neutron generator. As per the analytical results generator can produce more than 1 × 10^(12)n s^(-1)with a 110 keV D^(+) ion beam of 10 mA and a minimum 5 Ci tritium target. However, the detailed simulation with the more realistic conditions of deuteron ion interaction with the tritium titanium target shows that the desired results cannot be achieved with 110 keV. The safe limit of the ion energy should be 300 keV as per the simulation. At 300 keV ion energy and 20 mA current, it reaches 1.6 × 10^(12)n s^(-1). moreover, it was found that to ensure sufficiently long operation time a tritium target of more than 20 Ci should be used. The scope of the neutron source is not limited to the fusion reactor research studies, it is extended to other areas such as medical radioisotopes research, semiconductor devices irradiations, and many more.

关键词： neutron generator neutronics accelerator physics design nuclear fusion

Tuning the particle size,physical properties,and photocatalytic activity of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio

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Chinese Physics B 2023年第3期32卷 561-568页

作者： Hung N m Oanh l T m Chung D P Thang D V mai V T Hang l T minh N V Center for Nano Science and Technology Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Department of Physics Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Hanoi University of mining and Geology Duc Thang WardNorth Tu Liem DistrictHanoi 100000Vietnam Institute of materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoi 100000Vietnam Faculty of Basic Sciences Hanoi University of Natural Resources and Environment41 A Phu Dien RoadNorth Tu LiemHanoi 100000Vietnam

This study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)*** material characterizations were carried out using x-ray diffraction(XRD),scanning electron microscopy(SEm),energy-dispersive x-ray spectroscopy(EDX),Brunauer–Emmett–Teller(BET)surface area,Fourier transform infrared(FTIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),UV-vis absorption,and photoluminescence(Pl).The results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size *** change is also observed in the Raman scattering and FTIR spectra with the increase in the vibration frequency of the[PO_(4)]*** compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding *** photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light *** is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample.

关键词： morphology photocatalytic Ag^(+)/PO_(4)^(3-)ratio visible light

牙龈卟啉单胞菌超声提取物对人牙周膜干细胞骨向分化的影响

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现代口腔医学杂志 2007年第6期21卷 603-605页

作者：侯建霞 Peter m loomer barron Hong 北京大学口腔医学院 100081 美国加利福尼亚大学旧金山分校

目的本研究目的是检测牙龈卟啉单胞菌(Porphyromonas gingivalis,***)2561超声提取物对人牙周膜干细胞(Human periodontal ligament stemcells,hPDlSCs)的增殖及其骨向分化相关蛋白表达的影响。方法标准厌氧培养环境下培养***。收集细... 详细信息

目的本研究目的是检测牙龈卟啉单胞菌(Porphyromonas gingivalis,***)2561超声提取物对人牙周膜干细胞(Human periodontal ligament stemcells,hPDlSCs)的增殖及其骨向分化相关蛋白表达的影响。方法标准厌氧培养环境下培养***。收集细菌菌落,离心,制备细菌的超声提取物,然后以不同的浓度加入hPDlSCs的培养液中。培养六天后观察hPDlSCs的增殖及碱性磷酸酶(Alkaline phosphatase,AlPase)的表达。提取蛋白并用Western Blotting检测骨黏结蛋白(Osteonectin,ON)的表达。结果与对照组相比,***明显抑制hPDlSCs的生长(PlSCs中AlPase的表达(PlSCs的增殖及其骨向分化能力,抑制了牙周炎症所致牙周组织破坏后牙周组织的自我修复能力。

关键词：牙周膜干细胞牙龈卟啉单胞菌骨向分化碱性磷酸酶骨黏结素

Effect of cold-working on corrosion induced damage in lug joints

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Defence Technology（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath m.N Chikmath l. murthy H. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

lug joints are preferred joineries for transferring heavy loads to parent components in aerospace *** experience corrosion due to environmental conditions,improper surface finishes and rubbing displacement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is modelled as a through-pit at one of the identified critical locations through stress *** effect of this pit on fatigue crack initiation life is ***-hole is pre-stressed by cold-working and the benefits of inducing plastic wake on the intended performance of the lug joint during the damages due to corrosion are brought out and compared with non-cold-worked *** analysis is performed on this lug joint with *** results obtained highlight the benefits of cold-working and the methodology can be extended to damage growth and analyse the effect of surface treatments for better structural integrity of components of aerospace vehicles.

关键词： lug joint Corrosion Crack initiation Cold-working Structural integrity

Reliability of quasi integrable and non-resonant Hamiltonian systems under fractional Gaussian noise excitation

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Acta mechanica Sinica 2020年第4期36卷 902-909页

作者： Q.F.lu W.Q.Zhu m.l.Deng Department of mechanics State-Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou 310027China

The reliability of quasi integrable and non-resonant Hamiltonian system under fractional Gaussian noise(fGn)excitation is *** rather flat fGn power spectral density(PSD)in most part of frequency band,the fGn is innovatively regarded as a wide-band ***,the stochastic averaging method for quasi integrable Hamiltonian systems under wide-band noise excitation is applied to reduce 2n-dimensional original system into n-dimensional averaged ltd stochastic differential equations(SDEs).Reliability function and mean first passage time are obtained by solving the associated backward Kolmogorov equation and Pontryagin *** validity of the proposed procedure is tested by applying it to an example and comparing the numerical results with those from monte Carlo simulation.

关键词： Reliability Fkst passage time Quasi integrable and non-resonant Hamiltonian systems Fractional Gauss noise

Photocatalytic performance of K2Ti6O13 whiskers to H2 evolution and CO2 photo-reduction

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Journal of Energy Chemistry 2019年第10期28卷 18-28页

作者： l. F. Garay-Rodríguez l.m.Torres-martínez E.moctezuma Facultad de Ingeniería Civil-Departamento de Ecomateriales y Energía Universidad Autónoma de Nuevo LeónAv. Universidad S/N Cd. UniversitariaC. P. 66455 San Nicolás de los GarzaNLMéxico Facultad de Ciencias Químicas Universidad Autónoma de San Luis PotosíAv. Manuel Nava#6C. P.78290 San Luis PotosíSLPMéxico

K2Ti6O13 whiskers were synthesized by conventional sol-gel method, sono-chemical assisted and microwave assisted sol-gel method in order to obtain catalysts with different particle sizes and to modify their optical, textural and electrochemical properties. These modifications improved their photocatalytic activity for H2 evolution and CO2 photo-reduction. long K2Ti6O13 whiskers prepared by ultrasound assisted sol-gel method are the most active photocatalysts for the hydrogen evolution reaction using pure water as reactant (U-SG, 10,065 μmol g^-1). In contrast, an opposite behavior was observed using a mixture of ethanol-water, where the highest activity was achieved by the shortest and less crystalline K2Ti6O13 whiskers (C-SG, 3,2871 μmol g^-1). In case of CO2 photo-reduction, long whiskers that were also prepared by the sono-chemical assisted sol-gel method were the most active to transform CO2 to formaldehyde, methane, methanol and hydrogen. The EFB value of this catalyst is located very close to the potential for formaldehyde production and favors the selectivity to this organic product.

关键词： K2Ti6O13 Sol-gel Whiskers Hydrogen evolution CO2 reduction

Prediction of strength and deformability of an interlocked blocky rock mass using UDEC

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Journal of Rock mechanics and Geotechnical Engineering 2017年第3期9卷 149-160页

作者： Y.m.Alshkane A.m.marshall l.R.Stace Department of Civil Engineering University of Sulaimani Sulaimani Kurdistan Region Iraq Department of Civil Engineering University of Nottingham University Park Nottingham NG7 2RD UK

The accurate prediction of strength and deformability characteristics of rock mass is a challenging *** practice,properties of a rock mass are often estimated from available empirical relationships based on the uniaxial compressive strength(UCS).However,UCS does not always give a good indication of in situ rock mass strength and *** aim of this paper is to present a methodology to predict the strength and deformability of a jointed rock mass using UDEC(universal distinct element code).In the study,the rock mass is modelled as an assemblage of deformable blocks that can yield as an intact material and/or slide along predefined joints within the rock mass.A range of numerical simulations of uniaxial and triaxial tests was conducted on rock mass samples in order to predict the equivalent mechanical properties for the rock mass under different loading ***,results are compared with the deformability parameters obtained by analytical methods.

关键词： Strengt Deformability ock mass Universal distinct element code(UDEC)