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无机化学学报 1988年第4期 79-90页

作者： Lewandowski, w. Department of Physico-Chemical Analyses Agricultural University of warsaw 02-528 warsaw Rakowiecka 26/30 Poland

In this paper,the aromaicity of some metal benzoates has been studied us-ing IR,Raman and UV spectroscopic *** bond frequencies in IR andRaman spectra of Hg(Ⅰ),Mg and K benzoates are summarised in table *** of Cr(Ⅲ),Fe(Ⅲ),Cu(Ⅱ),*** the aromatic system of benzoic acidwere *** is found that Cr(Ⅲ)iron(Ⅲ),Ianthanides and Al can stabi-lize this system.

关键词： aromaticity metal benzoate IR Raman UV spectroscopy

The Classical Description of the Meissner Effect: Theory and Applications

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Open Journal of Applied Sciences 2023年第3期13卷 275-287页

作者： Elie w’ishe Sorongane Physics Department University of Kinshasa Kinshasa Democratic Republic of the Congo

when we place a superconductor above a magnet, we observe a levitation of the superconductor above the magnet. But when placing a perfect diamagnetic material above a magnet, no levitation is observed. This difference in behavior between the superconductor and the perfect diamagnetic in the presence of an external magnetic field is explained by the classical description of the Meissner effect implemented in this article. we have shown here that the Meissner effect is nothing more than an electromagnetic interaction between the magnetic field created by the superconductor and the magnetic field of the magnet. This classical description of the Meissner effect also allowed us to give a more realistic explanation of the expansion of the universe. we have shown that this expansion is a phenomenon that simply results from a Meissner effect between superconducting dark matter and the magnetic fields of stars. we also pointed out that this expansion is accelerated because the gravitational force between dark matter and the stars around it decreases as these stars move away from the superconducting dark matter. we also used this classical description of the Meissner effect to propose a new method of remote sensing in space in which the superconducting satellite is in perpetual levitation on the night side of the earth and a new and more efficient way to discover new particles through a superconducting detector levitating in the upper atmosphere.

关键词： Meissner Effect Levitation Superconducting Dark Matter Remote Sensing Satellite Cosmic Radiation

Thermal stability and deformation mechanisms in Ni-Co-Fe-Cr-Al-Ti-Nb-type nanoparticle-strengthened high-entropy alloys

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Journal of Materials Science & Technology 2023年第36期167卷 171-183页

作者： J.X.Hou J.Y.Zhang J.X.Zhang J.H.Luan Y.X.wang B.X.Cao Y.L.Zhao Z.B.Jiao X.J.Liu w.w.Song P.K.Liaw T.Yang Department of Materials Science and Engineering Hong Kong Institute for Advanced StudyCity University of Hong KongHong KongChina School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina Steel Institute RWTH Aachen UniversityAachen 52072Germany Institute of Materials Engineering University of KasselKassel 334125Germany Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996-2200USA City University of Hong Kong China

The precipitate morphologies,coarsening kinetics,elemental partitioning behaviors,grain structures,and tensile properties were explored in detail for L1_(2)-strengthened Ni_(39.9)Co_(20)Fe_(15)Cr_(15)Al_(6)Ti_(4-x)Nb_(x)B_(0.1)(x=0 at.%,2 at.%,and 4 at.%)high-entropy alloys(HEAs).By substituting Ti with Nb,the spheroidal-to-cuboidal precipitate morphological transition,increase in the coarsening kinetics,and phase decomposition upon aging at 800°C *** excessive addition of Nb brings about the grain boundary precipitation of an Nb-rich phase along with the phase decomposition from the L1_(2)to lamellar-structured D019 phase upon the long-term aging *** partially substituting Ti with Nb,the chemically complex and thermally stable L12 phase with a composition of(Ni_(58.8)Co_(9.8)Fe_(2.7))(Al_(12.7)Ti_(5.8)Nb_(7.5)Cr_(2.3))ensures the stable phase structure and clean grain boundaries,which guarantees the superb high-temperature mechanical properties(791±7 MPa for yielding and 1013±11 MPa for failure)at 700℃.Stacking faults(SFs)were observed to prevail during the plastic deformation,offering a high work-hardening capability at 700°*** anomalous rise in the yield strength at 800℃was found,which could be ascribed to the multi-layered super-partial dislocations with a cross-slip configuration within the L1_(2)particles.

关键词： High-entropy alloys Coarsening kinetics Coherent precipitation strengthening Mechanical properties

The Open Quantum Materials Database (OQMD): assessing the accuracy of DFT formation energies

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npj Computational Materials 2015年第1期1卷 15-29页

作者： Scott Kirklin James E Saal Bryce Meredig Alex Thompson Jeff w Doak Muratahan Aykol Stephan Rühl Chris wolverton Department of Materials Science and Engineering Northwestern UniversityEvanstonILUSA FIZ Karlsruhe—Leibniz Institute for Information Infrastructure Eggenstein-LeopoldshafenGermany

The Open Quantum Materials Database(OQMD)is a high-throughput database currently consisting of nearly 300,000 density functional theory(DFT)total energy calculations of compounds from the Inorganic Crystal Structure Database(ICSD)and decorations of commonly occurring crystal *** maximise the impact of these data,the entire database is being made available,without restrictions,at ***/*** this paper,we outline the structure and contents of the database,and then use it to evaluate the accuracy of the calculations therein by comparing DFT predictions with experimental measurements for the stability of all elemental ground-state structures and 1,670 experimental formation energies of *** represents the largest comparison between DFT and experimental formation energies to *** apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/*** order to estimate how much error to attribute to the DFT calculations,we also examine deviation between different experimental measurements themselves where multiple sources are available,and find a surprisingly large mean absolute error of 0.082 eV/***,we suggest that a significant fraction of the error between DFT and experimental formation energies may be attributed to experimental ***,we evaluate the stability of compounds in the OQMD(including compounds obtained from the ICSD as well as hypothetical structures),which allows us to predict the existence of~3,200 new compounds that have not been experimentally characterised and uncover trends in material discovery,based on historical data available within the ICSD.

关键词： Quantum DFT Open

The microbiome as a potential diagnostic biomarker for pancreatic ductal adenocarcinoma(PDAC)

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Hepatobiliary Surgery and Nutrition 2022年第5期11卷 752-754页

作者： Roseanna C.wheatley Juan w.Valle Mairéad G.McNamara Division of Cancer Sciences School of Medical SciencesFaculty of Biology Medicine and HealthUniversity of ManchesterManchesterUK Department of Medical Oncology The Christie NHS Foundation TrustManchesterUK

Pancreatic ductal adenocarcinoma(PDAC)is a major cause of cancer-related death *** recent advances in treatment options,prognosis remains poor,and data estimates from the United States(us)show that PDAC will surpass colorectal cancer to become the second most common cause of cancer-related death by 2040(1).Surgery followed by adjuvant chemotherapy is the only potentially curative treatment option for patients with PDAC;however,the majority present with advanced stage,non-resectable *** diagnosis could improve the dismal prognosis for this patient group,but this remains challenging due to numerous factors including a lack of approved biomarkers and screening programmes,and non-specificity or late presentation of symptoms.

关键词： Surgery adenocarcinoma diagnosis

First-principles calculations of hyperfine interaction,binding energy,and quadrupole coupling for shallow donors in silicon

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npj Computational Materials 2020年第1期6卷 186-194页

作者： Michael w.Swift Hartwin Peelaers Sai Mu John J.L.Morton Chris G.Van de walle Department of Physics University of CaliforniaSanta BarbaraCA 93106-9530USA us Naval Research Laboratory Center for Computational Materials ScienceWashingtonDC 20375USA Materials Department University of CaliforniaSanta BarbaraCA 93106-5050USA Department of Physics and Astronomy University of KansasLawrenceKansas 66045USA Department of Electronic and Electrical Engineering UCLLondonWC1E 7JEUK

Spin qubits based on shallow donors in silicon are a promising quantum information technology with enormous potential scalability due to the existence of robust silicon-processing ***,the most accurate theories of donor electronic structure lack predictive power because of their reliance on empirical fitting parameters,while predictive ab initio methods have so far been lacking in accuracy due to size of the donor wavefunction compared to typical simulation *** show that density functional theory with hybrid and traditional functionals working in tandem can bridge this *** first-principles approach allows remarkable accuracy in binding energies(67 meV for bismuth and 54 meV for arsenic)without the use of empirical *** also obtain reasonable hyperfine parameters(1263 MHz for Bi and 133 MHz for As)and superhyperfine *** demonstrate the importance of a predictive model by showing that hydrostatic strain has much larger effect on the hyperfine structure than predicted by effective mass theory,and by elucidating the underlying mechanisms through symmetry analysis of the shallow donor charge density.

关键词： density donor hyperfine

Strong parallel evidence of selection during switchgrass sward establishment in hybrid and lowland ecotypes

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Grassland Research 2022年第1期1卷 31-42页

作者： Neal w.Tilhou Shawn M.Kaeppler Michael D.Casler Department of Agronomy University of WisconsinMadisonWisconsinUSA usDA-ARS U.S.Dairy Forage Research CenterMadisonWisconsinUSA

Background:Switchgrass sward establishment results in up to 90%seedling *** degree of selection during sward establishment has not been reported using modern genetic ***:Pooled leaf samples were sequenced from replicated swards of 46 half-sib families from two breeding groups(lowland and hybrid)before and through 3 years of stand *** allele frequencies were then assessed using fixation indices(Fst)and an independent data set was used to predict the polygenic impact of establishment selection on two traits(heading date and winter survivorship).Last,the DNA pools were assigned survival rankings to predict the sward survival genomically estimated breeding values within the training data ***:Strong and parallel selection occured in both breeding *** genomic regions exceeded the significant threshold of 99.9%in>10 families,indicating consistent selection across families and breeding *** trait predictions determined that establishment selection was partially associated with winter survivorship but resulted in variable heading date *** genomewide variation is consistent with selection for a small number of related parental ***:This study observed strong selection for a small number of hybrid and coastal ecotype individuals which are promising germplasm sources for improved sward *** confirms prior reports of sward selection during grassland establishment and highlights the strength of pooled DNA sequencing for survival traits.

关键词： genomic prediction grassland establishment Panicum virgatum polygenic traits selection

Chemistry-led investigations into the mode of action of NAMPT activators,resulting in the discovery of non-pyridyl class NAMPT activators

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Acta Pharmaceutica Sinica B 2023年第2期13卷 709-721页

作者： Siyuan Tang Miguel Garzon Sanz Oliver Smith Andreas Krämer Daniel Egbase Paul w.Caton Stefan Knapp Sam Butterworth Division of Pharmacy and Optometry School of Health SciencesManchester Academic Health Sciences CentreUniversity of ManchesterManchester M139PLUK Structural Genomics Consortium(SGC) 60438 Frankfurt Am MainGermany Buchmann Institute for Life Sciences(BMLS) 60438 Frankfurt Am MainGermany Institut für Pharmazeutische Chemie Goethe University60438 Frankfurt Am MainGermany Frankfurt Cancer Institute(FCI) 60596 Frankfurt Am MainGermany Department of Diabetes School of Cardiovascular and Metabolic Medicine&SciencesFaculty of Life Sciences&MedicineKing's College LondonLondon SE11ULUK

The cofactor nicotinamide adenine dinucleotide(NAD+)plays a key role in a wide range of physiological processes and maintaining or enhancing NAD+levels is an established approach to enhancing healthy ***,several classes of nicotinamide phosphoribosyl transferase(NAMPT)activators have been shown to increase NAD+levels in vitro and in vivo and to demonstrate beneficial effects in animal *** best validated of these compounds are structurally related to known urea-type NAMPT inhibitors,however the basis for the switch from inhibitory activity to activation is not well *** we report an evaluation of the structure activity relationships of NAMPT activators by designing,synthesising and testing compounds from other NAMPT ligand chemotypes and mimetics of putative phosphoribosylated adducts of known *** results of these studies led us to hypothesise that these activators act via a through-water interaction in the NAMPT active site,resulting in the design of the first known urea-class NAMPT activator that does not utilise a pyridine-like warhead,which shows similar or greater activity as a NAMPT activator in biochemical and cellular assays relative to known analogues.

关键词： Nicotinamide phosphoribosyl transferase activator Healthy aging Drug discovery Bioisosteres Medicinal chemistry

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Strategies towards robust interpretations of in situ zircon Lu-Hf isotope analyses

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Geoscience Frontiers 2020年第3期11卷 843-853页

作者： C.J.Spencer C.L.Kirkland N.M.w.Roberts N.J.Evans J.Liebmann School of Earth and Planetary Sciences The Institute for Geoscience Research(TIGeR)Curtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada Centre for Exploration Targeting-Curtin Node The Institute for Geoscience ResearchSchool of Earth and Planetary SciencesCurtin UniversityPerthAustrali Geochronology and Tracers Facility British Geological SurveyNottinghamUK John de Laeter Centre GeoHistory Facility School of Earth and Planetary SciencesCurtin UniversityPerthAustralia

The combination of U-Pb and Lu-Hf compositions measured in zircon crystals is a remarkably powerful isotopic couplet that provides measures on both the timing of mineral growth and the radiogenic enrichment of the source from which the zircon *** U-Pb age documents the timing of zircon crystallization/recrystallization and Hf isotopes inform on the degree to which the host melt was derived from a radiogenic reservoir(*** mantle) versus an unradiogenic reservoir(*** continental crust),or some mixture of these *** ease of generating large quantities of zircon U-Pb and Lu-Hf data has been in large part facilitated by instrument ***,the dramatic increase in time constrained zircon Lu-Hf analyses in the Earth science community has brought to the fore the importance of careful data collection and reduction workflows,onto which robust geological interpretations may be *** this work,we discuss the fundamentals of Lu-Hf isotopes in zircon,which then allows us to provide a robust,accessible,methodology for the assessment of data ***,we discuss some novel techniques for:data visualization—that facilitates better transparency of data interpretation;integration of geographic information—that may reveal spatial trends where temporal trends were only apparent before;and some novel statistical evaluation tools—that may provide more rigorous interand intra-sample comparisons.

关键词： Zircon Geochronology Isotope geochemistry Lu-Hf isotopes Geostatistics Data visualization

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Microbial and size characterization of airborne particulate matter collected on sticky tapes along us–Mexico border

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Journal of Environmental Sciences 2017年第3期29卷 207-216页

作者： Amir Gonzalez-Delgado Manoj K.Shukla David w.DuBois Juan P.Flores-Mdrgez Joel A.Hernandez Escamilla Evangelina Olivas Plant and Environmental Sciences Department New Mexico State UniversityMSC 3Q Skeen Hall Room N 127P.O.Box 30003Las CrucesNM 88003-8003USA Universidad Autonoma de Ciudad Judrez UACJAv.Plutarco Elias Calles 1020Fovisste ChamizalCiudad JudrezChihuahua C.P.32310Mexico

Particulate matter （PM） emissions from various sources can affect significantly human health and environmental quality especially in the Chihuahuan Desert region along us- Mexico border. The objective of this study was to use the low-cost sticky tape method to collect airborne PM for size characterization and identification of fungal spores. Sticky tape samplers were placed at 1.0 and 2.0 m above the ground surface at experimental sites in Ciudad Ju＆ez, Mexico and at 0.6, 1.2 and 1.8 m at New Mexico sites, usA. Soil samples were collected in both countries to determine fungal diversity, texture and moisture content. Dust particles collected from all of the experimental sites had a dominant texture of clay （〈0.002 mm）. The dominant textures identified from soil samples collected from the us and Mexican sites were loam and sandy clay loam, respectively. Alternaria, Penicillium and Fusarium were frequently found funguses in the us sites while Alternaria and Aspergillus were commonly observed in the Mexican sites. The sticky tapes also showed a similar diversity of fungal microorganisms present in the airborne PM at both Mexico and us sites. Alternaria, Penicillium and Aspergillus were the three groups of airborne fungal microorgan- isms consistently present in the us and Mexican sites. The low-cost sticky tape method has the potential to be used for characterizing different airbome microorganisms and dust particles.

关键词： Fungal sporesSticky tapeParticle sizeMicroorganismDust

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