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Super-hydrophobic stearic acid layer formed on anodized high purified magnesium for improving corrosion resistance of bioabsorbable implants

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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

Time series analysis of mantle cycles Part Ⅱ:The geologic record in zircons, large igneous provinces and mantle lithosphere

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Geoscience Frontiers 2019年第4期10卷 1327-1336页

作者： Kent C. Condie Stephen J. Puetz Department of Earth & Environmental Science New Mexico Institute of Mining and TechnologySocorroNM87801USA Progressive Science institute HonoluluHI96815USA

Igneous and detrital zircons have six major U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distributions and a subpeak age range per age peak≤100 *** are eight major LIP age peaks(found on≥10 crustal provinces)of which only four are in common to major detrital zircon age peaks(2715 Ma,1875 Ma,825 Ma,90 Ma).Of the whole-rock Re depletion ages,58%have correspo nding detrital zircon age peaks and 55%have corresponding LIP age *** age pea ks are fou nd in common to igneous zircon,detrital zircon,LIP,and Re depletion age time series(3225 Ma,2875 Ma,2145 Ma,2085 Ma,1985 Ma,1785 Ma,1455 Ma,1175 Ma,825 Ma,and 90 Ma).and these are very robust peaks on a global scale as recorded in both crustal and mantle *** 50%of the age peaks in each of these time series correspond to predicted peaks in a 94-Myr mantle cycle,including four of the ten peaks in common to all four time series(2875 Ma,1785 Ma,825 Ma and 90 Ma).Age peak widths and subpeak ranges per age peak suggest that mantle events responsible for age peaks are2500 Ma),with the number of new provinces in which age peaks are represented decreasing with time within each *** breaks between the populations(at 2.5 Ga and 1 Ga)fall near the onsets of two transitions in Earth *** First Transition may represent a change from stagnant-lid tectonics into plate tectonics and the Second Transition,the onset of subduction of continental *** major factor controlling geographic distribution of age peaks is the changing locations of ***^2 Ga,age subpeaks and peaks are housed in orogens within or around the edges of crustal provinces,mostly in accretionary *** beginning at 1.9 Ga,collisional orogens become more *** coincidence in duration

关键词： Isotopic age peaks U/Pb zircon ages Re depletion ages Large igneous provinces Age peak correlation Mantle cycles

PRELIMINARY STUDY ON CHLORINE-36 DATING OF HALITE IN SALT LAKES FROM QAIDAM BASIN

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Chinese Science Bulletin 1990年第1期35卷 32-36页

作者：黄麒 Fred M.Phillips institute of Salt Lakes Academia Sinica Xining 810008 PRC new mexico institute of mining and technology USA

The Qaidam Basin is a large intermontane depression. It has been in existence since the Jurassic. The mean elevation of the basin floor is 2800 m. It covers an area of 120,000 km^2 with a catchment area of about 250,000 km^2. By the end of the Pliocene, great changes had taken place. Some of the lakes were evolving to the evaporite formation stage. The deposition continued through the Pliocene and the late Pleistocene to produce a sequence 2000—3000 m thick, and the total thickness of halite sequence is more than 1000 m. The Qaidam Basin contains some of the richest salt resources, the sediments deposited on

关键词： salt lake halite chlorine-36 dating.

Factors affecting use of ballistics gelatin in laboratory studies of bacterial contamination in projectile wounds

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Military Medical Research 2018年第4期5卷 304-313页

作者： Jessica J. Evans Aaron Bost Karim H. Muci-Küchler Linda C. DeVeaux Biomedical Engineering Program South Dakota School of Mines and Technology Mechanical Engineering Department South Dakota School of Mines and Technology Department of Biology New Mexico Institute of Mining and Technology

Background: Ballistics gelatin is a common tissue surrogate used in bacterial contamination models for projectile wounds. Although these studies have demonstrated that bacteria are transferred from the surface of the gelatin to the wound track by a projectile, quantifiable results have been inconsistent and not repeatable in successive ***: In this study, five areas of a typical contamination model in which bacterial recovery or survival are affected were identified for optimization. The first was a contaminated "skin" surrogate, where the novel use of vacuum filtration of a bacterial culture and buffer onto filter paper was employed. The other possibly problematic areas of the bacterial distribution model included the determination of bacterial survival when the contamination model is dried, survival in solid and molten gelatin, and the effect of high-intensity lights used for recording high-speed ***: Vacuum filtration of bacteria and buffer resulted in a consistent bacterial distribution and recovery. The use of phosphate buffer M9(pH 7) aided in neutralizing the ballistics gelatin and improving bacterial survival in solid gelatin. Additionally, the use of high-intensity lights to record high-speed video and the use of a 42℃ water bath to melt the gelatin were found to be bactericidal for gram-positive and gram-negative ***: Multiple areas of a typical contamination model in which bacterial survival may be impeded were identified, and methods were proposed to improve survival in each area. These methods may be used to optimize the results of bacterial contamination models for medical applications, such as understanding the progression of infection in penetrating wounds and to identify possible sources of contamination for forensic purposes.

关键词： Ballistics gelatin Wound Contamination Bacterial model

Charge structures and cloud-to-ground lightning discharges characteristics in two supercell thunderstorms

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Chinese Science Bulletin 2006年第2期51卷 198-212页

作者： ZHANG Yijun MENG Qing LU Weitao Paul Krehbiel LIU Xinsheng ZhOU Xiuji Chinese Academy of Meteorological Sciences Beijing 100081 China new mexico institute of mining and technology Socorro New Mexico 87801 USA Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou 730000 China

The charge structures and temporal and spatial characteristics of cloud-to-ground (CG) light- ning discharges in two supercell thunderstorms have been analyzed based on the data of three-dimen- sional VHF radiation sources with high time and space resolution produced by lightning discharges. The results indicate that the charge structures in main part (convective region) of the thunderstorms were inverted tripole while a number of positive CG lightning discharges were occurring in the two thun- derstorms. The positive CG lightning discharges oc- curred in main part of the thunderstorms and origi- nated from the positive charge region located at the middle part of the thunderstorms. While a number of negative CG lightning discharges were occurring, the negative CG lightning discharges occurred in the anvil of the thunderstorm. The charge structure is inverted dipole in the region due to the slant of charge structure in main region toward anvil region. The negative charge region located at the upper part of anvil produced a lot of negative CG lightning dis- charges. No or less CG lighting was produced di- rectly by the charge region located at the lower part of the thunderstorm. The charge region in lower part of the thunderstorm plays an important role for the occurrence of CG lightning from charge region above it.

关键词：雷暴电荷结构云地闪电放电特征

Effect of acid fracturing fluid modifying coal microstructure stimulated by ultrasonic

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International Journal of mining Science and technology 2025年第2期 275-293页

作者： Shaojie Zuo Rui Gan Zhijie Wen Liang Zhang Zhizhong Jiang Fuping Zhao Chengwei Liu Kun Li Zhiyuan Xu College of mining Guizhou University Shandong Key Laboratory of mining Disaster Prevention and Control Shandong University of Science and Technology School of Emergency Management Xihua University Guizhou Research institute of Oil & Gas Exploration and Development Engineering Liupanshui Normal University

The combination of ultrasonic and acid fracturing fluid can strengthen the modification effect on the micropore structure of the coal matrix, thereby enhancing the efficiency of the acid fracturing *** this research, acetic acid was utilized to formulate acid fracturing fluids with varying concentrations,and the evolutionary traits of both the acid fracturing fluids and ultrasonic waves in relation to coal samples were investigated. The functional group structure, mineral composition, micropore structure and surface morphology of coal samples were characterized by FTIR, XRD, N2adsorption at low temperature and SEM-EDS. The results showed that aromatics（I） and branching parameters（CH2/CH3） were reduced by 81.58% and 88.67%, respectively, after 9% acetic acid treatment. Acetic acid can dissolve carbonates and clay minerals in coal, create new pores, and increase porosity, pore volume and pore fractal dimension. After modification by 7% acetic acid, the pore volume increased by 5.7 times. SEM observation shows that the diameter of coal surface holes increases, EDS scanning shows that the content of mineral elements in coal decreases, the connectivity of coal holes increases, and the holes expand. The findings of this research offer theoretical direction for optimizing ultrasonic-enhanced acid fracturing fluid modification.

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Ophiolites:Identification and tectonic significance in space and time

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Geoscience Frontiers 2023年第6期14卷 380-385页

作者： Kent C.Condie Robert J.Stern Department of Earth&Environmental Science New Mexico Institute of Mining and TechnologySocorroNM 87801USA Geosciences Department University of Texas at DallasRichardsonTX 75080USA

Ophiolites are fragments of oceanic lithosphere that are produced at spreading centers at ocean ridges,back arc basins,or forearcs during subduction initiation,and are key indicators of plate *** it is widely agreed that ophiolites are remnants of oceanic crust and associated depleted mantle preserved in orogens,the recognition of ophiolites and their tectonic significance is still a topic of discussion and *** propose that ophiolites can be recognized in the geologic record by some combination of genetically related pillow basalt,layered gabbro,sheeted dykes,podiform chromite,harzburgite or/and *** igneous rocks have either ocean-ridge basalt or immature oceanic arc basalt chemical *** a scoring system of 1–11 for ophiolite confidence level,scores of8 are considered confident,6–8 probable,and900 Ma ophiolites is probably real.

关键词： Ophiolite Plate tectonics Subduction initiation Forearc Ocean ridge Tectonic setting Supercontinent

Tomographic reconstruction of the Earth’s magnetosheath from multiple spacecraft:a theoretical study

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Earth and Planetary Physics 2024年第1期8卷 204-214页

作者： A.M.Jorgensen TianRan Sun Y.Huang L.Li R.Xu L.Dai Chi Wang new mexico institute of mining and technology SocorroNMUSA National Space Science Center Chinese Academy of SciencesBeijing 100190China Tsinghua University Beijing 100084China

Following our earlier work on tomographic reconstruction of the magnetosheath soft X-ray emissions with superposed epoch analysis of many images recorded from a single spacecraft we now explore the instantaneous reconstruction of the magnetosheath and magnetopause using a few images recorded simultaneously from a few *** work is motivated by the prospect of possibly having two or three soft X-ray imagers in space in the coming years,and that many phenomena which occur at the magnetopause boundary,such as reconnection events and pressure pulse responses,do not lend themselves as well to superposed epoch *** the reconstruction is successful-which we demonstrate in this paper that it can be-this collection of imagers can be used to reconstruct the magnetosheath and magnetopause from a single image from each spacecraft,allowing for high time resolution *** this paper we explore the reconstruction using,two,three,and four *** show that the location of the subsolar point of the magnetopause can be determined with just two satellites,and that volume emissions of soft X-rays,and the shape of the boundary,can be reconstructed using three or more satellites.

关键词： magnetosheath tomography soft X-ray imaging SMILE

SYNTHESIS AND CHARACTERISTICS OF A CHELATING RESIN AS AN EXTRACTANT AND CHROMOGENIC REAGENT OF HEAVY METAL IONS IN SOLID PHASE EXTRACTION

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Chinese Journal of Polymer Science 2013年第8期31卷 1108-1116页

作者：张田林 Hui-min Ma Jia-jia Wang Cai-yan Zhu Bing-bing Wang Department of Chemical Engineering Huaihai Institute of Technology School of Chemical Engineering & technology University of Mining and Technology College of Environment and Spatial Informatics University of Mining and Technology

A new chelating resin （CPS-DMA-SABA） was synthesized with the chloromethylated crossqinked polystyrene porous beads （CPS） as raw materials, which were bonded with salicylidene-o-aminobenzoic acid （SABA） on the surface via a quaternary ammonium unit as a linker. The results showed that CPS-DMA-SABA would easily change into a zwitterionic chelating resin （CPS-DMA-SABZ） when washed with distilled water. CPS-DMA-SABA was characterized by elemental analysis, infrared spectra and thermo-gravimetric analysis. The ion sorption capacities of CPS-DMA-SABA were found to be 1916 μg/g for Zn2＋ withpH at 4.5, 1620μg/g for Cu2＋ with pH at 6.2, 1291 μg/g for Ni2＋ withpH at 6.6 and 780 μg/g for Cr3＋ withpH at 5.5, respectively. The experiments showed CPS-DMA-SABA also changed its color when meeting with the metal ion in the aqueous solution. As a consequence, CPS-DMA-SABA can not only be used as a solid phase extractant but also an indicator for confirming the heavy metal ion in solutions.

关键词： Solid phase extractant Zwitterionic chelating resin Heavy metal ion o-Aminobenzoic acid Synthesis.