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基于超声波实验研究压力及流体对致密岩石横波衰减特征的影响

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Applied Geophysics 2024年第2期21卷 246-264,419页

作者：潘旭铭巴晶马汝鹏刘卫华程卫 JoséM.Carcione 河海大学地球科学与工程学院南京211100 东北石油大学三亚海洋油气研究院三亚572000 中石化石油物探技术研究院有限公司南京211100 National Institute of Oceanography and Applied Geophysics(OGS) TriesteItaly

我国致密油气储层勘探前景广阔,开采价值高,但其储层岩石具有低孔、低渗、强非均质性等特征,建立储层波响应与岩石物性参数之间的联系仍面临挑战,针对致密储层波响应规律的研究有待深入开展。孔隙流体性质及围压会影响岩石的剪切模量及... 详细信息

我国致密油气储层勘探前景广阔,开采价值高,但其储层岩石具有低孔、低渗、强非均质性等特征,建立储层波响应与岩石物性参数之间的联系仍面临挑战,针对致密储层波响应规律的研究有待深入开展。孔隙流体性质及围压会影响岩石的剪切模量及横波衰减,本文对部分饱和的8块致密岩石在不同围压条件下开展了超声波实验观测,采用谱比法估算岩石的横波衰减。结果显示,横波衰减随围压上升而下降,且饱水岩石的横波衰减大于饱油,饱气状态衰减最弱。气、水部分饱和岩石的测量结果中,岩石样本的横波衰减在中间含水饱和度达到峰值,此外,横波衰减随孔隙度、渗透率上升均有增大的趋势。基于实验测量的岩石物性参数,结合Voigt-Reuss-Hill(VRH)平均、微分等效介质模型和喷射流模型构建了致密岩石衰减模型,分析了不同围压条件下含流体岩石的衰减特征,结果显示,该模型可合理描述横波衰减特征。在完全饱和与部分饱和条件下,模型预测的横波衰减显示出明显的压力及流体敏感性。以样本TS1-19为例,在完全饱和、变围压条件下,模型预测的横波衰减峰值在11.6~69.5范围内,衰减峰值随着围压增大而降低,且峰值频率有向高频端移动的趋势。在部分饱和、围压30MPa条件下,模型预测的横波衰减峰值在15.5~39.8范围内,衰减峰值随着含水饱和度增大而增大,且峰值频率向低频端移动。对于所有样本,以30MPa围压为例,所预测的横波衰减在5.6~38.6范围内,其中在饱和条件下,模型预测横波衰减随着孔隙度增大而增大,随着围压增大而减小;在气水部分饱和条件下,随着含水饱和度的增大,基于模型及Voigt和Reuss边界法预测的横波衰减整体呈增大的趋势,而实验观测到的横波衰减在中间饱和度达到极大值。

关键词：致密岩石横波衰减岩石物理实验围压流体饱和度喷射流模型

1,8-萘酰亚胺衍生物的设计、合成及其对半胱氨酸的识别研究

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有机化学 2024年第1期44卷 180-194页

作者：杨维清葛宴兵陈元元刘萍付海燕马梦林西华大学理学院四川省不对称合成与手性技术重点实验室成都610039 四川大学化学学院教育部绿色化学重点实验室成都610064

巯基氨基酸水平异常与多种疾病相关,其检测仍存在一定的局限,研究检测巯基氨基酸的荧光探针具有一定的价值.以苊为原料合成了61个1,8-萘酰亚胺衍生物,研究了该类化合物的荧光性能及其作为半胱氨酸含量测定的荧光探针的可能性.紫外光谱... 详细信息

巯基氨基酸水平异常与多种疾病相关,其检测仍存在一定的局限,研究检测巯基氨基酸的荧光探针具有一定的价值.以苊为原料合成了61个1,8-萘酰亚胺衍生物,研究了该类化合物的荧光性能及其作为半胱氨酸含量测定的荧光探针的可能性.紫外光谱分析表明1,8-萘酰亚胺衍生物上N-取代基对最大吸收波长无明显影响;荧光光谱(fl)的性能测试显示硝基萘酰亚胺衍生物N-甲基-4-硝基-1,8-萘二甲酰亚胺(4a)~4-硝基-N-间氟苯基-1,8-萘二甲酰亚胺(4s)无荧光,氨基萘酰亚胺衍生物N-甲基-4-氨基-1,8-萘二甲酰亚胺(5a)~4-氨基-N-间氟苯基-1,8-萘二甲酰亚胺(5s)有强烈黄色荧光,而马来酰亚胺萘酰亚胺衍生物N-甲基-4-(1H-吡咯-2,5-二酮-1-基)-1,8-萘二甲酰亚胺(6a)~4-(1H-吡咯-2,5-二酮-1-基)-N-(间氟苯基)-1,8-萘二甲酰亚胺(6s)有微弱蓝色荧光,其中7个马来酰亚胺萘酰亚胺衍生物探针对半胱氨酸(Cys)溶液有荧光点亮效应.对7个探针加入21种其它氨基酸作为干扰项的测试显示探针对半胱氨酸检测有良好的选择性.研究了不同pH值下荧光强度,检测探针与半胱氨酸的响应时间,以及探针溶液荧光强度随氨基酸浓度的变化,其线性相关系数均达到0.95以上,探针对半胱氨酸的各项指标均表现出了较好的灵敏性.Hela细胞荧光成像验证了7个荧光探针应用于细胞内半胱氨酸的检测同样效果良好.

关键词：合成荧光探针半胱氨酸细胞成像 1,8-萘酰亚胺衍生物

Experimental investigation on variability in properties of Amazonian wood species Muiracatiara ( Astronium lecointei ) and maçaranduba ( manilkara huberi ) focusing guitar fingerboards manufacturing

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Journal of Bioresources and Bioproducts 2021年第1期6卷 33-38页

作者： Roseli Felix da Silva Ribeiro Joséflávio Silveira Feiteira Jayme Pereira de Gouvê Alexandre Furtado Ferreira Federal fluminense University PPGEMVolta RedondaRJBrazil Federal fluminense University PGMECVolta RedondaRJBrazil

In face of scarcity in the supply of non-traditional Brazilian woods properly treated for use in high quality musical instruments,pieces of Amazonian wood species muiracatiara(Astronium lecointei)and maçaranduba(manilkara huberi)purchased in the common internal Brazilian timber market were *** species were pre-selected for use in fingerboards of acoustic and electric guitars due to similar properties with ebony(Diospyros crassiflora).Variabilities of elastic modulus parallel to grain and density were investigated inside wooden *** addition,referred parameters were used in calculation of speed of *** tests were performed in order to compare both species and revealed inequality for variances of dynamic elastic modulus(E_(d))and speed of sound,but equality for *** of means was also examined via unequal variance *** color differences,lower variability of *** led to the indication of this species as likely capable to substitute satisfactorily ebony in fingerboards manufacturing.

关键词： Mechanical properties variability Wood grain slope Experimental analysis Impulse excitation technique F-test

Exploring magneto-electric nanoparticles(MENPs):a platform for implanted deep brain stimulation

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Neural Regeneration Research 2023年第1期18卷 129-130页

作者： małgorzata Kujawska Ajeet Kaushik Department of Toxicology Poznan University of Medical SciencesPoznańPoland NanoBioTech Laboratory Health Systems EngineeringDepartment of Natural SciencesFlorida Polytechnic UniversityLakelandFLUSA

Towards implanted deep brain stimulation(D B S):The human brain i s a complex network of 86 billion neurons and 85 billion nonneuronal cells and they are coordinated in a well-defined ratio(1:1)which is required for desired body *** connectivity among neuronal cells secretes neurotransmitters(e.g.,dopamine)to establish a perfect connection between the brain and a peripheral system i.e.,motor coordination.

关键词： stimulation dopamine implanted

Integrable nonlocal PT-symmetric generalized so(3,R)-mKdV equations

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Communications in Theoretical Physics 2023年第12期75卷 19-24页

作者： Shou-Ting Chen Wen-Xiu ma School of mathematics and Statistics Xuzhou University of TechnologyXuzhou 221008JiangsuChina Department of mathematics Zhejiang Normal UniversityJinhua 321004ZhejiangChina Department of mathematics King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of mathematics and Statistics University of South FloridaTampaFL 33620-5700United States of America School of mathematical and Statistical Sciences North-West UniversityMafikeng CampusPrivate Bag X2046Mmabatho 2735South Africa

Based on a soliton hierarchy associated with so(3,R),we construct two integrable nonlocal PT-symmetric generalized mKdV *** key step is to formulate two nonlocal reverse-spacetime similarity transformations for the involved spectral matrix,and therefore,integrable nonlocal complex and real reverse-spacetime generalized so(3,R)-mKdV equations of fifth-order are *** resulting reduced nonlocal integrable equations inherit infinitely many commuting symmetries and conservation laws.

关键词： integrable equation lax pair nonlocal reduction PT-symmetry zero curvature equation

基于matlab汽车双质量飞轮扭振仿真试验研究

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时代汽车 2024年第6期 158-160,170页

作者：冯振威马能武徐旭黄河交通学院河南省焦作市454000 中国农业机械化科学研究院集团有限公司北京市100083

由于汽车动力传动系统的自由度、分布质量、刚度和阻尼不统一,所以在工作的过程中会受到许许多多的扭转振动,产生振动和噪声,减少结构强度,影响行车的安全性与舒适性。因此,降低动力传动系的产生的振动具有十分重要的意义,双质量飞轮可... 详细信息

由于汽车动力传动系统的自由度、分布质量、刚度和阻尼不统一,所以在工作的过程中会受到许许多多的扭转振动,产生振动和噪声,减少结构强度,影响行车的安全性与舒适性。因此,降低动力传动系的产生的振动具有十分重要的意义,双质量飞轮可以合理地减少动力传动系统带来扭振。文章利用matlab软件建立了汽车传动系统在不同工况下的扭振模型,通过该模型详细分析和对比了双质量飞轮和从动盘扭转减振器的减振效果,结果表明双质量飞轮更有利于减少扭振的发生。

关键词：双质量飞轮从动盘扭转减振器 matlab 扭振模型

Hamiltonian Tri-Integrable Couplings of the AKNS Hierarchy

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Communications in Theoretical Physics 2013年第4期59卷 385-392页

作者： MENG Jing-Han ma Wen-Xiu Department of mathematics and Statistics University of South Florida 4202 E. Fowler Avenue Tampa FL 33620 USA

We propose a systematic approach for generating Hamiltonian tri-integrable couplings of soliton hierarchies. The resulting approach is based on semi-direct sums of matrix Lie algebras consisting of 4× 4 block matrix Lie algebras. We apply the approach to the AKNS soIRon hierarchy, and Hamiltonian structures of the obtained tri-integrable couplings are constructed by the variational identity.

关键词： tri-integrable coupling non-semisimple matrix loop algebra AKNS hierarchy bi-Hamiltonianstructure symmetry conservation law

Lump solutions to a generalized Bogoyavlensky-Konopelchenko equation

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Frontiers of mathematics in China 2018年第3期13卷 525-534页

作者： Shou-Ting CHEN Wen-Xiu ma School of mathematics and Physical Science Xuzhou Institute of Technology Xuzhou 221008 China Department of mathematics and Statistics University of South Florida Tampa FL 33620 USA College of mathematics and Systems Science Shandong University of Science and Technology Qingdao 266590 China International Institute for Symmetry Analysis and mathematical Modelling Department of Mathematical Sciences North-West University Mafikeng Campus Mmabatho 2735 South Africa

A （2 ＋ 1）-dimensional generalized Bogoyavlensky-Konopelchenko equation that possesses a Hirota bilinear form is considered. Starting with its Hirota bilinear form, a class of explicit lump solutions is computed through conducting symbolic computations with maple, and a few plots of a specific presented lump solution are made to shed light on the characteristics of lumps. The result provides a new example of （2 ＋ 1）-dimensional nonlinear partial differential equations which possess lump solutions.

关键词： Symbolic computation lump solution soliton theory

Non-Semisimple Lie Algebras of Block matrices and Applications to Bi-Integrable Couplings

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Advances in Applied mathematics and Mechanics 2013年第5期5卷 652-670页

作者： Jinghan Meng Wen-Xiu ma Department of mathematics and Statistics University of South FloridaTampaFL 33620-5700USA

We propose a class of non-semisimple matrix loop algebras consisting of 3×3 block matrices,and form zero curvature equations from the presented loop algebras to generate bi-integrable *** are made for the AKNS soliton hierarchy and Hamiltonian structures of the resulting integrable couplings are constructed by using the associated variational identities.

关键词： Bi-integrable couplings non-semisimple matrix loop algebras AKNS hierarchy Hamiltonian structure symmetry