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南美磁卫星标量异常图

世界地质 1991年第3期10卷 51-59页

作者： j.R.Ridgway w.j.hinze 李春华

南美及其毗邻海区的标量磁异常图已经根据磁卫星数据绘制出来。这项工作提出一些值得重视的问题,如分离外源场和地壳异常、异常化到同一高度等。外源场是表现为长波长的环流效应、中波长的赤道电射流和短波长的噪声干扰。环流被一个波... 详细信息

南美及其毗邻海区的标量磁异常图已经根据磁卫星数据绘制出来。这项工作提出一些值得重视的问题,如分离外源场和地壳异常、异常化到同一高度等。外源场是表现为长波长的环流效应、中波长的赤道电射流和短波长的噪声干扰。环流被一个波长滤波器增强后,利用标准环流方程加以改正;电射流由于主要出现在黄昏时刻的剖面中,仅用黎明剖面数据勾绘,就可将它的影响减至最小,而噪声则是通过选择“磁静日” (K≤2^+)方法来消除。最优化滤波的截止值是用统计回归方法确定的,大约为50度的波长值;当大于这个值的波长被抑制掉后,与从其它卫星轨道得到的剖面有很好的相关,仅有一些由于卫星高度不同造成的差别。而这些差别可进一步借助于等效点源反演方法使之归一化到同一高度来消除。最终结果图与原有的以2度进行平均的图有明显不同,特别是在低磁纬度区。这张图化极后,显示了与南美和加勒此地区构造特征的相关性。

关键词：磁性卫星标量异常图

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： H w A Riaz j Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

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北美区域重磁相关异常

世界地质 1985年第1期 73-87页

作者： R.R.B.Von Frese w.j.hinze L.w.Braile 张曼珠

重磁异常结合其他地质、地球物理资料进行相关分析,有利于提高位场异常地质解释的质量。利用等效点源反演绘制的图件,来研究北美及相邻海域的地面自由空间重力异常、POGO(线轨道地球物理观测)卫星磁异常,以及区域热流和构造信息间的视... 详细信息

重磁异常结合其他地质、地球物理资料进行相关分析,有利于提高位场异常地质解释的质量。利用等效点源反演绘制的图件,来研究北美及相邻海域的地面自由空间重力异常、POGO(线轨道地球物理观测)卫星磁异常,以及区域热流和构造信息间的视一空间相关关系。在卫星高度上相关异常的区域位场,也用泊松理论在重、磁场导数异常之间,移动窗口线性回归作定量分析。在大陆地区观测到长波长重磁异常之间的一种反相关关系。重力异常为负、磁力异常为正的地区,其特点是地壳相对较厚,磁化强度较高。例如:一个突出的磁力高与爱那达科盆地向辛辛那堤穹窿延伸的重力低相对应。磁力异常为负、重力异常为正的地区,其特征是地壳较薄,区域热流值较高。如:北美和中美洲的科迪勒拉地区,以及黄石地热区。虽然,海洋区域的重磁异常显示弱相关,但统计相关的符号一般为正。

关键词：重磁异常正异常反相关磁力高自由空间重力异常北美

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.jeong S.w.Lee w.j.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.Liu S.j.Liu B.wang w.B.Sun X.j.Liu Z.w.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China weihai Institute for Bionics-jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),w-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).when the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj/m^(3)to 10.97 Mj/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.j.Hall O.Hetherington T.w.Buggey T.Arnold M.w.j.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

Resistive field generation in intense proton beam interaction with solid targets

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： w.Q.wang j.j.Honrubia Y.Yin X.H.Yang F.Q.Shao Department of Physics National University of Defense TechnologyHunanChina ETSI Aeronáutica y del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Technology National University of Defense TechnologyHunanChina

The Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed hybrid code to model ion beam-plasma *** simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in which they compete with each *** the target is not completely ionized,the self-generated resistive field effect dominates over the ion scattering ***,when the target is completely ionized,this situation is ***,it is found that Ohmic heating is important for higher current densities and materials with high *** energy fraction deposited as Ohmic heating can be as high as 20%-30%.Typical ion divergences with half-angles of about 5°-10°will modify the proton energy deposition substantially and should be taken into account.

关键词： interaction beam intense

Genetics of biochemical attributes regulating morpho-physiology of upland cotton under high temperature conditions

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journal of Cotton Research 2024年第1期7卷 29-44页

作者： MAjEED Sajid CHAUDHARY Muhammad Tanees MUBARIK Muhammad Salman RANA Iqrar Ahmad SHABAN Muhammad TAN Daniel KY jIA Yinhua DU Xiongming hinze Lori AZHAR Muhammad Tehseen Federal Seed Certification and Registration Department Ministry of National Food Security and ResearchIslamabad 44090Pakistan Horticultural Research Institute National Agricultural Research CentreIslamabad 44000Pakistan Department of Biotechnology University of NarowalNarowal 51600Pakistan Centre of Agricultural Biochemistry and Biotechnology University of AgricultureFaisalabad 38400Pakistan Department of Plant Breeding and Genetics University of Agriculture FaisalabadSub-Campus BurewalaVehariPakistan Faculty of Science School of Life and Environ-mental SciencesPlant Breeding InstituteSydney Institute of AgricultureThe University of SydneySydneyNSW 2006Australia State Key Laboratory of Cotton Biology Institute of Cotton Research of Chinese Academy of Agri-cultural ScienceAnyang 455000China Agricultural Research Service USDASouthern Plains Agricultural Research CentreCollege StationTX 77845USA Department of Plant Breeding and Genetics University of AgricultureFaisal-abad 38400Pakistan School of Agriculture Sciences Zhengzhou UniversityZhengzhou 450000China.

Background Cotton is a strategically important fibre crop for global textile *** profoundly impacts several countries’industrial and agricultural *** cotton production is continuously threatened by the unpre-dictable changes in climate,specifically high *** heat-tolerant,high-yielding cotton cultivars with wide adaptability to be grown in the regions with rising temperatures is one of the primary objectives of modern cotton breeding ***,the main objective of the current study is to figure out the effective breed-ing approach to imparting heat tolerance as well as the judicious utilization of commercially significant and stress-tolerant attributes in cotton ***,the two most notable heat-susceptible(FH-115 and NIAB Kiran)and tolerant(IUB-13 and GH-Mubarak)cotton cultivars were spotted to develop filial and backcross populations to accom-plish the preceding study *** heat tolerant cultivars were screened on the basis of various morphological(seed cotton yield per plant,ginning turnout percentage),physiological(pollen viability,cell membrane thermostabil-ity)and biochemical(peroxidase activity,proline content,hydrogen peroxide content)*** The results clearly exhibited that heat stress consequently had a detrimental impact on every studied plant trait,as revealed by the ability of crossing and their backcross populations to tolerate high ***,when considering overall yield,biochemical,and physiological traits,the IUB-13×FH-115 cross went over particularly well at both normal and high temperature ***,overall seed cotton yield per plant exhibited a posi-tive correlation with both pollen viability and antioxidant levels(POD activity and proline content).Conclusions Selection from segregation population and criteria involving pollen viability and antioxidant levels concluded to be an effective strategy for the screening of heat-tolerant cotton g

关键词： Accessions Biochemical Breeding Cotton Generation mean analysis Heat stress

The CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.w.j.Hubbard O.Hetherington D.j.Hall T.w.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation