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Paleoclimatic application of spectral parameters to the eolian red clay of the Jianzha Basin,northeastern margin of the Tibetan Plateau

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Science China earth Sciences 2024年第6期67卷 1952-1966页

作者： Chaofeng FU Ju’e TIAN Xinwen XU Yougui SONG Jun ZUO Feng WANG Lin CHeN Pengfei LI Xiaoke QIANG The School of earth Science and Resources Chang’an UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth and EnvironmentCASXi’an 710061China College of Urban and environmental Science Northwest UniversityXi’an 710069China CAS Center for excellence in Quaternary Science and Global Change Xi’an 710061China

Reflectance spectroscopy is rapid,inexpensive,and non-destructive and can provide important information about the mineralogy of rocks and *** measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau,with the aim of developing a rapid methodology for detecting paleoclimatic *** obtained visible/near-infrared(VNIR)and short-wave infrared(SWIR)spectroscopy data from the red clay in the Jianzha Basin,and analyzed their relationship with independent paleoclimatic records,including mineral contents and environmental magnetic *** results show that the VNIR parameters,including D500,D900,R500,and R900(where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm,respectively)are temperature-sensitive and correlated with the magnetic susceptibility,frequency-dependent magnetic susceptibility,and the marine δ^(18)O *** results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital *** parameters,such as AS1400,D1400/D1900 and D1900(where AS represents the asymmetry of the absorption peaks around1400 nm),are correlated with the illite and montmorillonite content,and they are sensitive to the weathering *** spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at~8.5 Ma and global climatic cooling at~7.2 Ma,and thus they are applicable as both regional and global paleoenvironmental indicators.

关键词： Visible/near-infrared spectroscopy Short-wave infrared spectroscopy Paleoclimatic indicators Red clay Tibetan Plateau

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自主水下航行器发展概述（英文）

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船舶力学 2016年第6期20卷 768-787页

作者： ALAAeLDeeN M.e.Ahmed 段文洋军事技术学院船舶工程学院埃及开罗哈尔滨工程大学船舶工程学院哈尔滨150001

自主水下航行器(AUVs)因其应用于海洋勘探而逐渐成为一个有趣的研究对象。波浪滑翔机是一种行驶于波浪表面的无人滑行器(SUV),它借助海洋能来推动自己,这对于典型的AUVs所采用的电机供能以及昂贵的锚链系统浮标供能来说,是一种技术上的... 详细信息

自主水下航行器(AUVs)因其应用于海洋勘探而逐渐成为一个有趣的研究对象。波浪滑翔机是一种行驶于波浪表面的无人滑行器(SUV),它借助海洋能来推动自己,这对于典型的AUVs所采用的电机供能以及昂贵的锚链系统浮标供能来说,是一种技术上的重大跨越。该文讨论了最有效率的AUVs类型。第一部分为每一种类型的发展历程,第二部分为它们各自的技术特点。此外,波浪滑翔机作为应用于海洋部门的一种新型水下机器人,文中简要地给出它的过去,现在以及未来的发展概述。研究波浪滑翔机的意义在于证明它的效率以及实用性,进而取代诸多的AUVs来实现各种实际应用。而研究结果也表明波浪滑翔机确实可以应用于众多领域。对于海洋检测而言,相比于其他AUVs,波浪滑翔机提供了更廉价,更经济,更环保的作业模式,同时也不需要缆绳、船舶等海上作业服务。

关键词：自主水下航行器(AUV) 水下滑行器波浪滑翔机

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GRADING OF RABBIT SKeLeTAL MUSCLe TRAUMA BY DIFFUSION TeNSOR IMAGING AND TRACTOGRAPHY ON MAGNeTIC ReSONANCe IMAGING

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Chinese Medical Sciences Journal 2006年第4期21卷 276-280页

作者： Hui Zeng Jun-hui Zheng Jin-e Zhang Yan-hui Liu Department of Radiology Center of Medical Imaging Department of Pathology Guangdong Provincial People＇s Hospital Guangzhou 510080

Objective To distinguish the edema, injury, or rupture in the traumatic skeletal muscle fiber in vivo using diffusion tensor imaging （DTI） and tractography on magnetic resonance imaging （MRI）. Methods The skeletal muscle trauma models were made in 4 rabbits （ eight hindlimbs） by iron discus （ weight 1. 0 kg, diameter 6 cm） falling down vertically from 45 cm height to rabbits＇ thighs. Conventional sequences and two-dimensional （2D） diffusion-weighted （DW） spin-echo （Se） echo planar imaging （ePI） sequence with fat suppression （ b = 600 s/mm^2 ） were performed on 1.5T MRI scanner. The grading of edema, injury, and fiber rupture in the damaged muscle were made according to their histopathological views, which was consistent with the images. The mean apparent diffusion coefficient （ADC） values and fractional anisotropy （FA） values were measured from the region of interests （ROIs） of all groups on 2D DW images used for tractography. Analysis of variance test was performed to analyze all data. Results ADC values of the areas in normal muscle, edema muscle, injury muscle, and ruptured muscle were （6. 12±1.34 ） × 10^-3, （ 6.38±1.30 ） × 10^-3, （ 8.06±0. 97 ） × 10^-3, and （ 9. 57±0. 93 ） × 10^-3 mm^2/s, respectively. There was significant difference among groups （P 〈0. 001 ）, but no difference between edema muscle and normal muscle group （P 〉0. 05）. The FA values of normal muscle, edema muscle, injury muscle, and ruptured muscle were 0. 42±0. 12, 0. 36±0. 12, 0. 26±0. 09, 0. 12±0. 08, respectively, with a significant difference among groups （ P 〈 0. 001 ）. In the edema muscle, the tracking cross-fiber could be seen but it decreased slightly. In the injury muscle, the tracking fiber decreased markedly. In the ruptured muscle, the transverse-orientation tracking fiber vanished, yet some interrupted longitudinal-orientation tracking fiber could be found. Conclsion The edema, injury, and rupture of muscle fiber in rabbit damaged skeletal muscle can be verified according to the

关键词： traumatic skeletal muscle grade diffusion tensor imaging tractography

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Hemoglobin Adducts as Biomarkers of exposure to and metabolic Activation of Carcinogenic Tobacco-Specific Nitrosamines

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Biomedical and environmental Sciences 1991年第1期4卷 93-103页

作者： STePHeN S.HeCHT STeVeN G.CARMeLLA SHARON e.MURPHY Dana Road American Health Foundation ValhallaDana Road American Health Foundation ValhallaDana Road American Health Foundation Valhalla New York 10595New York 10595 New York 10595

The carcinogenic tobacco-specific nitrosamines N-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-l-(3-pyridyl)-l-butanone (NNK) form hemoglobin adducts in laboratory animals and humans. These adducts release 4-hydroxy-l-(3-pyridyl)-l-butanone (HPB) upon mild base hydrolysis. HPB released from human hemoglobin can be quantified by gas chromatography-mass spectrometry. It is the only available biochemical marker for determination of exposure to, and metabolic activation of, carcinogens present only in tobacco. Levels of HPB were highest in snuff-dippers, followed by smokers and nonsmokers. Large interindividual variations in adduct levels were observed. The relationship between HPB levels in globin and DNA of rats treated with NNK has been investigated in order to aid in interpretation of the data from humans. These studies have provided the initial database for understanding the metabolic activation of tobacco-specific nitrosamines in humans.

关键词： Hemoglobin Adducts as Biomarkers of exposure to and metabolic Activation of Carcinogenic Tobacco-Specific Nitrosamines

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Control of stem cell fate by engineering their micro and nanoenvironment

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World Journal of Stem Cells 2015年第1期7卷 37-50页

作者： Michelle F Griffin Peter e Butler Alexander M Seifalian Deepak M Kalaskar UCL Division of Surgery and Interventional Science Centre for Nanotechnology and Regenerative Medicine University College London London NW3 2PF United Kingdom Department of Plastic and Reconstructive Surgery Royal Free Hampstead NHS Trust Hospital London NW3 2PF United Kingdom

Stem cells are capable of long-term self-renewal and differentiation into specialised cell types, making them an ideal candidate for a cell source for regenerative medicine. The control of stem cell fate has become a major area of interest in the field of regenerative medicine and therapeutic intervention. Conventional methods of chemically inducing stem cells into specific lineages is being challenged by the advances in biomaterial technology, with evidence highlighting that material properties are capable of driving stem cell fate. Materials are being designed to mimic the clues stem cells receive in their in vivo stem cell niche including topographical and chemical instructions. Nanotopographical clues that mimic the extracellular matrix(eCM) in vivo have shown to regulate stem cell differentiation. The delivery of eCM components on biomaterials in the form of short peptides sequences has also proved successful in directing stem cell lineage. Growth factors responsible for controlling stem cell fate in vivo have also been delivered via biomaterials to provide clues to determine stem cell differentiation. An alternative approach to guide stem cells fate is to provide genetic clues including delivering DNA plasmids and small interfering RNAs via scaffolds. This review, aims to provide an overview of the topographical, chemical and molecular clues that biomaterials can provide to guide stem cell fate. The promising features and challenges of such approaches will be highlighted, to provide directions for future advancements in this exciting area of stem cell translation for regenerative medicine.

关键词： Biomaterials Scaffold Stem cells Surfacetopography Tissue engineering

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Angular dependence of nanoparticle generation in the matrix assembly cluster source

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Nano Research 2019年第12期12卷 3069-3074页

作者： Maria Chiara Spadaro Junlei Zhao William D.Terry Jian Liu Feng Yin Flyura Djurabekova Richard e.Palmer College of engineering Swansea UniversityBay CampusFabian WaySwansea SAI 8ENUK Department of Physics and Helsinki Institute of Physics University of HelsinkiP.O.Box43f FIN-00014HelsinkiFinland Nanoscale Physics Research Laboratory School of Physics and AstronomyUniversity of BirminghamBirmingham B152TTUK National Center for electron Microscopy in Beijing Key Laboratory cf Advanced Materials(MOE)The State Key Laboratory of New Ceramics and Fine ProcessingSchool of Materials Science and EngineeringTsinghua UniversityBeijing 100084China School of Physics and Information Technology Shaanxi Normal UniversityXian 710062China Catalan Institute of Nanoscience and Nanotechnology(ICN2) CSIC and BISTCampus UABBellaterra08193 BarcelonaCataloniaSpain

The matrix assembly cluster source(MACS)represents a bridge between conventional instruments for cluster beam deposition(CBD)and thelevel of industrial *** method is based on Ar^+ion sputtering of a pre-condensed Ar-M matrix(where M,is typically a metal such asAg).each Ar^+ion produces a collision cascade and thus the formation of metal clusters is in the matrix,which are then sputtered *** wepresent an experimental and computational investigation of the cluster emission process,specifically its dependence on the Ar^+ion angle of in cidence and the cluster emission *** find the in cide nee angle strongly in flue nces the emerging cluster flux,which is assigned to thespatial location of the deposited primary ion energy relative to the cluster into the *** also found an approximately constant anglebetween the incident ion beam and the peak in the emitted cluster distribution,with value between 99°and 109°.

关键词： cluster beam deposition scale-up nano particles silver ligand-free green synthesis

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Comics, trauma, and the new art of war

Comics, trauma, and the new art of war

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作者： Harriet e.H. earle.

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effect of grain refinement on the hydrogen embrittlement of 304 austenitic stainless steel

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Journal of Materials Science & Technology 2019年第10期35卷 2213-2219页

作者： Y.H.Fan B.Zhang J.Q.Wang e.-H.Han W.Ke Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and engineering University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The effect of grain size(in the range from 4 μm to 12 μm) on the hydrogen embrittlement(He) of 304 austenitic stainless steel(ASS) was studied. He susceptibility result shows that He resistance increases with grain refinement. electron backscattered diffraction kernel average misorientation(eBSD-KAM)mapping shows that the strain localization can be mitigated by grain refinement. Hence, strain localization sites which act as highways for hydrogen diffusion and preferred crack initiation sites can be reduced along with grain refinement, leading to a high He resistance. Meanwhile, grain size shows no influence on the strain induced martensite(SIM) transformation during the hydrogen charging slow strain tensile test(SSRT). Hence, the SIM formed during hydrogen charging SSRT is not responsible for the different He resistance of 304 ASSs with various grain sizes. Hydrogen diffusion is supposed to be controlled by a competition between short-circuit diffusion along random grain boundary(RGB) and hydrogen trapping at dislocations, leading to a maximum hydrogen diffusion coefficient in the 304 ASS with an average grain size of 8 μm.

关键词： Stainless steel Grain refinement Hydrogen embrittlement SeM eBSD

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effect of Pd or Ir on the catalytic performance of Mo/H-ZSM-5 during the non-oxidative conversion of natural gas to petrochemicals

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Journal of Natural Gas Chemistry 2008年第4期17卷 337-343页

作者： Ahmed K.Aboul-Gheit Ahmed e.Awadallah Salah M.el-Kossy Abdel-Lateef H.Mahmoud Process Development Division Egyptian Petroleum Research Institute Faculty of Science Department of ChemistryMNF University Ageeba Petroleum Co.

Natural gas conversion to petrochemicals, principally, benzene, naphthalene, toluene, as well as ethylene under non-oxidative conditions was examined in a fixed bed flow reactor at 700 ℃ and gaseous hourly space velocity （GHSV） of 1500 ml·g ^-1·h^-1 at time-on-stream ranging from 5 rain to 4 h using catalysts containing 6.0%Mo/H-ZSM-5 promoted with Pd or Ir metal. The catalysts were characterized by XRD, TPD, and TGA. The addition of Pd or Ir to 6%Mo/H-ZSM-5 catalyst promoted ethylene production but inhibited the cyclization reaction to aromatics owing to the strong interaction between these noble metals and the framework Al species, which were attached to the acid sites during the impregnation process. Coke deposition on the catalysts was found to decrease upon addition of 0.5wt% of Pd or Ir to 6%Mo/H-ZSM-5 catalyst owing to the hydrogenating activity of these metals.

关键词： natural gas methane benzene ethylene molybdenum Pd Ir H-ZSM-5

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Comparison of Soil Biota Between Organic and Conventional Agroecosystems in Oregon, USA

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Pedosphere 2005年第3期15卷 395-403页

作者： WUShan-Mei HUDun-Xiao e.R.INGHAM UniversityofCalifornia BerkeleyCA94720（USA） ChinaAgriculturalUniversity Beijing100094（China） OregonStateUniversity CorvallisOR（USA）

Soil samples at 0-10 cm in depth were collected periodically at paired fields in Corvallis, Oregon, USA to compare differences in soil microbial and faunal populations between organic and conventional agroecosystems. Results showed that the organic soil ecosystem had a significantly higher (P erage number or biomass of soil bacteria; densities of flagellates, amoebae of protozoa; some nematodes, such as microbivorous and predaceous nematodes and plant-parasitic nematodes; as well as Collembola. Greater numbers of Rhabditida (such as Rhabditis spp.), were present in the organic soil ecosystem while Panagrolaimus spp. were predominant in the conventional soil ecosystem. The omnivores and predators of Acarina in the Mesostigmata (such as Digamasellidae and Laelapid), and Prostigmata (such as Alicorhaiidae and Rhagidiidae), were also more abundant in the organic soil ecosystem. However, fungivorous Prostigmata (such as Terpnacaridae and Nanorchestidae) and Astigmata (such as Acarida) were significantly higher (P e conventional soil ecosystem, which supported the finding that total fungal biomass was greater in the conventional soil ecosystem. Seansonal variations of the population depended mostly on soil moisture condition and food web relationship. The population declined from May to October for both agroecosystems. However, higher diversities and densities of soil biota survived occurred in the organic soil ecosystem in the dry season.

关键词： microarthropods nematodes organic and conventional agroecosystems soil microbial population

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