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Journal of Magnesium and Alloys 2018年第4期6卷 327-336页

作者： Sohrab Khalifeh T.David Burleigh Materials&Metallurgical Engineering Department New Mexico Institute of Mining&TechnologySocorroNM 87123USA

Magnesium and its alloys are ideal candidates for bioabsorbable ***,they can dissolve too rapidly in the human body for most *** this research,high purified magnesium(HP-Mg)was coated with stearic acid(SA)to slow the corrosion rate of magnesium in simulated body fluid at 37±1°***-Mg was anodized(AC and DC voltages)to form an oxide/hydroxide layer,and then it was immersed in a SA *** SA coated layer surface,anodized layer,and the thickness of the oxide/hydroxide layer were investigated with Scanning Electron Microscopy(SEM).Electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization(PDP)were used to estimate the corrosion rate of HP-Mg *** results confirm that the hydrophobic coating can decrease the corrosion rate of HP-Mg by more than *** protectiveness of coated layer for anodized specimens with AC voltage continue for 2 and 3 *** the HP-Mg coated anodized with DC voltage,the coated layer could improve the corrosion resistance for only a few days.

关键词： Magnesium Biomaterials Hydrophobic layer Stearic acid Simulated body fluid Electrochemical impedance spectroscopy

Novel self-assembled two-dimensional layered oxide structure incorporated with Au nanoinclusions towards multifunctionalities

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Nano Research 2023年第1期16卷 1465-1472页

作者： Di Zhang Xingyao Gao Juanjuan Lu Ping Lu Julia Deitz Jianan Shen Hongyi Dou Zihao He Zhongxia Shang C.Austin Wade Xinghang Zhang Aiping Chen Haiyan Wang School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA Center for Integrated Nanotechnologies(CINT) Los Alamos National LaboratoryLos AlamosNM 87545USA Sandia National Laboratories AlbuquerqueNM 87185USA School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47907USA Thermo Fisher Scientific HillsboroOR 97124USA

Two-dimensional(2D)layered oxides have recently attracted wide attention owing to the strong coupling among charges,spins,lattice,and strain,which allows great flexibility and opportunities in structure designs as well as multifunctionality *** parallel,plasmonic hybrid nanostructures exhibit exotic localized surface plasmon resonance(LSPR)providing a broad range of applications in nanophotonic devices and sensors.A hybrid material platform combining the unique multifunctional 2D layered oxides and plasmonic nanostructures brings optical tuning into the new *** this work,a novel self-assembled Bi2MoO6(BMO)2D layered oxide incorporated with plasmonic Au nanoinclusions has been demonstrated via one-step pulsed laser deposition(PLD)*** microstructural characterizations,including scanning transmission electron microscopy(STEM),differential phase contrast imaging(DPC),and STEM tomography,have demonstrated the high epitaxial quality and particle-in-matrix morphology of the BMO-Au nanocomposite ***-STEM imaging clarifies the magnetic domain structures of BMO *** different BMO structures including layered supercell(LSC)and superlattices have been revealed which is attributed to the variable strain states throughout the BMO-Au *** to the combination of plasmonic Au and layered structure of BMO,the nanocomposite film exhibits a typical LSPR in visible wavelength region and strong anisotropy in terms of its optical and ferromagnetic *** study opens a new avenue for developing novel 2D layered complex oxides incorporated with plasmonic metal or semiconductor phases showing great potential for applications in multifunctional nanoelectronics devices.

关键词： layered oxides plasmonic strain anisotropy multifunctionality

Organic Gases in Fluid Inclusions of Ore Minerals and Their Constraints on Ore Genesis:A Case Study of the Changkeng Au-Ag Deposit,Guangdong,China

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 86-94页

作者： DavidI.NORMAN Department of Earth & Environmental Sciences New Mexico Institute of Mining and Technology (NMT) Socorro NM87801 USA

The newly discovered Changkeng Au-Ag deposit is a new type of sediment-hostedprecious metal deposit. Most of the previous researchers believed that the deposit was formed bymeteoric water convection. By using a high vacuum quadrupole gas mass spectrometric system, ninelight hydrocarbons have been recognized in the fluid inclusions in ore minerals collected from theChangkeng deposit. The hydrocarbons are composed mainly of saturated alkanes C_(1-4) and unsaturatedalkenes C_(2-4) and aromatic hydrocarbons, in which the alkanes are predominant, while the contentsof alkenes and aromatic hydrocarbons are very low. The sum alka/sum alke ratio of most samples ishigher than 100, suggesting that those hydrocarbons are mainly generated by pyrolysis of kerogens insedimentary rocks caused by water-rock interactions at medium-low temperatures, and themetallogenic processes might have not been affected by magmatic activity. A thermodynamiccalculation shows that the light hydrocarbons have reached chemical equilibrium at temperatureshigher than 200 deg C, and they may have been generated in the deep part of sedimentary basins(e.g., the Sanzhou basin) and then be transported by ore-forming fluids to a shallow position of thebasin via a long distance. Most of the organic gases are generated by pyrolysis of the type IIkerogens (kukersite) in sedimentary host rocks, only a few by microorganism activity. Thecompositions and various parameters of light hydrocarbons in gold ores are quite similar to those insilver ores, suggesting that the gold and silver ores may have similar metallogenic *** on the compositions of organic gases in fluid inclusions, the authors infer that the Changkengdeposit may be of a tectonic setting of continental rift. The results of this study support fromone aspect the authors' opinion that the Changkeng deposit is not formed by meteoric waterconvection, and that its genesis has a close relationship with the evolution of the Sanzhou basin,so it belon

关键词： ore mineral fluid inclusion organic gas Changkeng Au-Ag deposit

Improved stability of superelasticity and elastocaloric effect in Ti-Ni alloys by suppressing Lüders-like deformation under tensile load

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Journal of Materials Science & Technology 2023年第15期146卷 154-167页

作者： Pengfei Dang Jianbo Pang Yumei Zhou Lei Ding Lei Zhang Xiangdong Ding Turab Lookman Jun Sun Dezhen Xue State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China AiMaterials Research LLC Santa FeNM 87501USA

Functional stability of superelasticity is crucial for practical applications of shape memory *** is degraded by a Lüders-like deformation with elevated local stress concentration under tensile *** increasing the degree of solute supersaturation and applying appropriate thermomechanical treatments,a Ti-Ni alloy with nanocrystallinity and dispersed nanoprecipitates is *** contrast to conventional Ti-Ni alloys,the superelasticity in the target alloy is accompanied by homogeneous deformation due to the sluggish stress-induced martensitic *** alloy thus shows a fully recoverable strain of 6%under tensile stress over 1 GPa and a large adiabatic temperature decrease of 13.1 K under tensile strain of 4.5%at room ***,both superelasticity and elastocaloric effect exhibit negligible degradation in response to applied strain of 4%during *** attribute the improved functional stability to low dislocation activity resulting from the suppression of localized deformation and the combined strengthening effect of nanocrystalline structure and ***,the design of such a microstructure enabling homogeneous deformation provides a recipe for stable superelasticity and elastocaloric effect.

关键词： Ti-Ni alloys Superelasticity Elastocaloric effect Martensite band Functional stability

Neonatal opioid exposure:public health crisis and novel neuroinflammatory disease

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Neural Regeneration Research 2021年第3期16卷 430-432页

作者： Vikram Vasan Yuma Kitase Jessie C.Newville Shenandoah Robinson Gwendolyn Gerner V.Joanna Burton Lauren L.Jantzie Department of Pediatrics Department of NeurologyJohns Hopkins University School of MedicineBaltimoreMDDepartment of NeurologyKennedy Krieger InstituteBaltimoreMDDepartment of PediatricsUniversity of New Mexico School of MedicineAlbuquerqueNMDepartment of NeurosciencesUniversity of New Mexico School of MedicineAlbuquerqueNMUSA

Substance use,specifically the use of prescription and non-prescription opioids among pregnant women,is a major public health issue and chief contributor to the opioid *** prevalence of Neonatal Opioid Withdrawal Syndrome has risen 5-fold in the past decade,and is a well-recognized consequence of perinatal opioid *** contrast,the long-term damage to the developing brain from opioid medications is just beginning to be recognized as a serious *** data suggest that opioid exposure commencing in utero negatively affects the maturation of the neural-immune system,and trajectory of central nervous system *** induces peripheral immune hyper-reactivity,lasting structural and microstructural brain injury,and significant deficits in executive function and cognitive control in adult animals following in utero ***,to address the cascading public health crisis stemming from the multitude of infants with in utero opioid exposure who will grow up with altered neurodevelopmental trajectories,rigorous preclinical,mechanistic studies are *** studies will define the long-term sequelae of prenatal opioid exposure in an effort to develop appropriate and targeted ***,the development of novel fluid,neuroimaging and biobehavioral biomarkers will be the most useful to aid in early identification and treatment of opioid exposed infants with the greatest risk of poor clinical *** studies will be essential to understand how in utero insults determine brain structure and function in adulthood,and what targeted interventions will be required to improve longterm outcomes in the countless children being born exposed to opioids each year.

关键词： biomarker buprenorphine cognition executive function magnetic resonance imaging methadone neonate

Information Measure for Size Distribution of Avalanches in the Bak—Sneppen Evolution Model

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Chinese Physics Letters 2003年第1期20卷 31-34页

作者：李炜蔡勖 InstituteofParticlePhysics HuazhongNormalUniversityWuhau430079 SantaFeInstitute 1399HydeParkRoadSantaFeNM87501USA InstituteofParticlePhysics HuazhongNormalUniversityWuhau430

Information of avalanche size distribution is measured by calculating information entropy (IE) in the Bak-Sneppen evolution model. It is found that the IE increases as the model evolves. Specifically, we establish the relation between the IE and the self-organized threshold fc. The variation of the IE near the critical point yields an exponent entropy index E = (τ-1)/σ, where τ and σ represent the critical exponents for avalanche size distribution and avalanche size cutoff, respectively. A new quantity Dτ(g) (g = 1-(fc-G)(τ-1)/σ, where G is the gap of the current state), defined as 1-Iτ(g)/Iτ(1), with Iτ(g) and Iτ(1) being the IE for the current state and the critical one respectively, is suggested that it represents the distance between the state with gap G and the critical one.

关键词： Size distribution

Acoustic radiation force and torque on a lossless eccentric layered fluid cylinder

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Chinese Physics B 2020年第11期29卷 140-145页

作者： F G Mitri Santa Fe NM 87508USA

Exact analytical equations and computations for the longitudinal and transverse acoustic radiation force and axial torque components for a lossless eccentric liquid cylinder submerged in a nonviscous fluid and insonified by plane waves progressive waves(of arbitrary incidence in the polar plane)are established and computed *** modal matching method and the translational addition theorem in cylindrical coordinates are used to derive exact mathematical expressions applicable to any inner and outer cylinder sizes without any approximations,and taking into account the interaction effects between the waves propagating in the layer and those scattered from the cylindrical *** results show that longitudinal and transverse radiation force components arise,in addition to the emergence of an axial radiation torque component acting on the non-absorptive compound cylinder due to geometrical asymmetry as the eccentricity *** computations demonstrate that the axial torque component,which arises due to a geometrical asymmetry,can be positive(causing counterclockwise rotation in the polar plane),negative(clockwise rotation)or neutral(rotation cancellation)depending on the size parameter of the cylinder and the amount of ***,verification and validation of the results have been accomplished from the standpoint of energy conservation law applied to scattering,and based on the reciprocity theorem.

关键词： acoustic radiation force acoustic radiation torque non-viscous liquid eccentric cylinder

Modeling the relationship between gene expression and mutational signature

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Quantitative Biology 2023年第1期11卷 31-43页

作者： Limin Jiang Hui Yu Yan Guo Department of Internal Medicine Comprehensive Cancer CenterUniversity of New Mexico AlbuquerqueNM 87109USA

Background:Mutational signatures computed from somatic mutations,allow an in-depth understanding of tumorigenesis and may illuminate early prevention *** studies have shown the regulation effects between somatic mutation and gene expression ***:We hypothesized that there are potential associations between mutational signature and gene *** capitalized upon RNA-seq data to model 49 established mutational signatures in 33 cancer *** accuracy and area under the curve were used as performance measures in five-fold ***:A total of 475 models using unconstrained genes,and 112 models using protein-coding genes were selected for future inference *** independent gene expression dataset on lung cancer smoking status was used for validation which achieved over 80%for both accuracy and area under the ***:These results demonstrate that the associations between gene expression and somatic mutations can translate into the associations between gene expression and mutational signatures.

关键词： mutational signature gene expression support vector machine random forest extreme gradient boost

Effect of loading direction on interaction of two pre-existing open and closed flaws in a rock-like brittle material

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Underground Space 2020年第3期5卷 242-257页

作者： Mahtab Alitalesh Mahmoud Yazdani Ahmadali Fakhimi Marjan Naeimabadi School of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran Department of Mineral Engineering New Mexico TechSocorroNMUSA

Investigations of the growth,interaction,and coalescence of cracks are important because they help to provide tools for the more realistic modeling of rock masses containing low persistence discontinuities and better estimations of the strength and stiffness of a rock *** the coalescence mechanism is useful for justifying the mechanism of continental crustal deformation,evaluating the structural failure of slopes with rock bridges,and analyzing the stability of tunnels when a mode I or mix mode failure mechanism is *** evaluation of crack growth can provide valuable information about the mechanism for the formation of new geological structures,and the formation,evolution,and growth of *** paper reports the results of diametrical compression tests on rocklike disk-shaped *** specimen contained two pre-existing open or closed *** growth,interaction,and coalescence of the pre-existing flaws were investigated both physically and numerically.A hybrid bonded particle-finite element system was used in the numerical *** results of the physical and numerical studies were in good *** particular,the induced crack patterns showed close agreement in the physical and numerical *** microscope image processing was used in the physical tests to study the dislocations along the initial *** was shown that wing crack formation was responsible for the failure of the specimen when flaws were inclined with respect to the loading *** crack growth and linkage were shown to be affected by the friction between faces of the *** addition,the slip distributions at the flaws surfaces were illustrated and examined to understand the crack propagation *** effects of the flaws on the disk failure loads were assessed both numerically and experimentally as well.

关键词： Pre-existing flaws Brazilian disk Fracture mechanics Crack propagation Coalescence Bonded particle simulation

The Error-Minimization-Based Strategy for Moving Mesh Methods

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Communications in Computational Physics 2006年第1期1卷 53-80页

作者： Konstantin Lipnikov Mikhail Shashkov Los Alamos National Laboratory MS B284Los AlamosNM87545USA

The typical elements in a numerical simulation of fluid flow using moving meshes are a time integration scheme,a rezone method in which a new mesh is defined,and a remapping(conservative interpolation)in which a solution is transferred to the new *** objective of the rezone method is to move the computational mesh to improve the robustness,accuracy and eventually efficiency of the *** this paper,we consider the onedimensional viscous Burgers’equation and describe a new rezone strategy which minimizes the L2 norm of error and maintains mesh *** efficiency of the proposed method is demonstrated with numerical examples.

关键词： Moving meshes Burgers’equation error estimates