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mollisols Properties and Changes in Ukraine and China

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Chinese Geographical Science 2011年第3期21卷 257-266页

作者： Yuri S KRAVCHENKO ZHANG Xingyi LIU Xiaobing SONG Chunyu richard m CRUSE Key Laboratory of mollisols Agroecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China National University of Life and Environmental Sciences of Ukraine Kyiv 03041 Ukraine Department of Agronomy Iowa State University Ames 500011 IA USA

Soils are the foundation of civilizations and the basis for human food *** in Ukraine and Northeast China are two out of the four major mollisol regions in the *** natural areas from which mollisols developed are the prairies and steppes that experience temperate and freezing *** review paper introduces the general climate,vegetation,and topography of mollisols regions in Ukraine and Northeast China,analyzes their properties,including soil texture,soil organic matter content,soil bulk density,pH,cation exchange capacity and other chemical properties,and compares the property changes and management practices of mollisols in relation to sustainable grain production.

关键词： mollisols soil properties soil organic matter tillage mollisols management

Deep subwavelength nanometric image reconstruction using Fourier domain optical normalization

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Light(Science & Applications) 2016年第1期5卷 632-640页

作者： Jing Qin richard m Silver Bryan m Barnes Hui Zhou Ronald G Dixson mark-Alexander Henn Engineering Physics Division Physical Measurement LaboratoryNational Institute of Standards and Technology100 Bureau Dr MS 8212GaithersburgMD 20899-8212USA

Quantitative optical measurements of deep subwavelength,three-dimensional(3D),nanometric structures with sensitivity to sub-nanometer details address a ubiquitous measurement challenge.A Fourier domain normalization approach is used in the Fourier optical imaging code to simulate the full 3D scattered light field of nominally 15 nm-sized structures,accurately replicating the light field as a function of the focus *** the full 3D light field,nanometer scale details such as a 2 nm thin conformal oxide and nanometer topography are rigorously fitted for features less than one-thirtieth of the wavelength in *** densely packed structures are positioned nearly an order of magnitude closer than the conventional Rayleigh resolution limit and can be measured with sub-nanometer parametric *** approach enables a practical measurement sensitivity to size variations of only a few atoms in size using a high-throughput optical configuration with broad application in measuring nanometric structures and nanoelectronic devices.

关键词： computational microscopy light scattering metrology quantitative nanoscale microscopy sub-nanometer uncertainties

Single-particle photoluminescence connects thermal processing with heterogeneity in the trap distribution of cesium lead bromide nanocrystals

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Nano Research 2024年第12期17卷 10363-10375页

作者： Dong Wang Jie Chen Dongyan Zhang Dariusz m.Niedzwiedzki richard A.Loomis Bryce Sadtler Department of Chemistry Washington UniversitySt.LouisMissouri 63130USA Center for Solar Energy and Energy Storage Washington UniversitySt.LouisMissouri 63130USA Department of Energy Environmental&Chemical EngineeringWashington UniversitySt.LouisMissouri 63130USA Institute of materials Science&Engineering Washington UniversitySt.LouisMissouri 63130USA

Understanding the mechanisms of degradation in lead halide perovskite nanocrystals is critical for their future application in optoelectronic *** report single-particle measurements of the photoluminescence from cesium lead bromide nanocrystals coated with a silica shell(CsPbBr_(3)@SiO_(2)).Through correlative imaging,we quantified changes in the fluorescence intensity trajectories of the same nanocrystals before and after annealing them at different *** observe that nearly equal numbers of CsPbBr_(3)@SiO_(2) nanocrystals exhibit an increase versus decrease in the amount of time they spend in an emissive state after annealing at temperatures of 70 and 100℃.On the other hand,annealing at 120℃ produces a decrease in the on-fraction for most nanocrystals and,correspondingly,a substantial decrease in the photoluminescence intensity for a thin film annealed at this *** attribute the differences in behavior among individual nanocrystals to heterogeneity in the distribution of trap states that are initially present.X-ray photoelectron,time-resolved photoluminescence,and transient absorption spectroscopies performed on thin films of CsPbBr_(3)@SiO_(2) nanocrystals indicate that thermal annealing heals electron traps by passivating surface Pb ions and simultaneously creates hole traps through the formation of Pb and Cs *** relative rates of these parallel processes depend on the annealing temperature,which are important to account for when developing passivation strategies for lead halide perovskite nanocrystals in optoelectronic devices that will operate at elevated temperatures.

关键词： single-particle microscopy photoluminescence nanocrystals cesium lead bromide thermal annealing

Biomarker and animal models for assessment of retinoid efficacy in cancer chemoprevention

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Acta Pharmacologica Sinica 2007年第9期28卷 1383-1391页

作者： richard m NILES Department of Biochemistry and microbiology Joan C Edwards School of MedicineMarshall UniversityHuntingtonWV 25701USA

Vitamin A is essential for normal growth and *** andlaboratory studies suggest that decreased vitamin A levels and defective metabo-lism/action may contribute to the genesis of certain *** on thisinformation,natural and synthetic derivatives of vitamin A (retinoids) have beenused for chemoprevention of *** have had some success in thechemoprevention of leukoplakia and in the decreased incidence of second prima-ries in head and neck *** is little information on biomarkers that can beused to assess the efficacy of the chemopreventive activity of *** of retinoids to induce RARb has been consistently shown to correlate withthe response of cells and tissues to retinoic acid,but few other biomarkers havebeen certified as indicators of retinoid *** light of the failure of the ATBCand CARET clinical intervention trials for chemoprevention of lung cancer,greateruse of animal models for chemoprevention studies is *** potentialcombination of phytochemicals that inhibit DNA methyltransferase activity withretinoids holds promise for more effective chemoprevention of retinoid-unrespon-sive premalignant lesions.

关键词： vitamin A retinoic acid chemoprevention biomarkers animal models transgenic animals

Strategies towards statistically robust interpretations of in situ U-Pb zircon geochronology

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Geoscience Frontiers 2016年第4期7卷 581-589页

作者： Christopher J.Spencer Christopher L.Kirkland richard J.m.Taylor The Institute of Geoscience Research(TIGeR) Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Centre for Exploration Targeting-Curtin Node Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Australian Research Council Centre of Excellence for Core to Crust Fluid SystemsPerthWA 6102Australia

Zircon U-Pb geochronology has become a keystone tool across Earth science, arguably providing the gold standard in resolving deep geological time. The development of rapid in situ analysis of zircon （via laser ablation and secondary ionization mass spectrometry） has allowed for large amounts of data to be generated in a relatively short amount of time and such large volume datasets offer the ability to address a range of geological questions that would otherwise remain intractable （e.g. detrital zircons as a sedi- ment fingerprinting method）. The ease of acquisition, while bringing benefit to the Earth science com- munity, has also led to diverse interpretations of geochronological data. In this work we seek to refocus U -Pb zircon geochronology toward best practice by providing a robust statistically coherent workflow. We discuss a range of data filtering approaches and their inherent limitations （e.g. discordance and the reduced chi-squared; mSWD）. We evaluate appropriate mechanisms to calculate the most geologically appropriate age from both 238U/206pb and 207pb/206pb ratios and demonstrate the cross over position when chronometric power swaps between these ratios. As our in situ analytical techniques become progressively more precise, appropriate statistical handing of U-Pb datasets will become increasingly pertinent.

关键词： Zircon Geochronology U-Pb Geostatistics mSWD

Structural geometry of orogenic gold deposits： Implications for exploration of world-class and giant deposits

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Geoscience Frontiers 2018年第4期9卷 1163-1177页

作者： David I.Groves m.Santosh richard J.Goldfarb Liang Zhang Orebusters Pty Ltd Gwelup 6018 Western Australia Australia State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences Beijing 100083 China Centre for Tectonics Resources and Exploration Dept. of Earth Sciences University of Adelaide SA 5005 Australia Division of Interdisciplinary Science Faculty of Science Kochi University Kochi 780-8520 Japan

With very few exceptions, orogenic gold deposits formed in subduction-related tectonic settings in accretionary to collisional orogenic belts from Archean to Tertiary times. Their genesis, including metal and fluid source, fluid pathways, depositional mechanisms, and timing relative to regional structural and metamorphic events, continues to be controversial. However, there is now general agreement that these deposits formed from metamorphic fluids, either from metamorphism of intra-basinal rock sequences or de-volatilization of a subducted sediment wedge, during a change from a compressional to transpressional, less commonly transtensional, stress regime, prior to orogenic collapse. In the case of Archean and Paleoproterozoic deposits, the formation of orogenic gold deposits was one of the last events prior to cratonization. The late timing of orogenic gold deposits within the structural evolution of the host orogen implies that any earlier structures may be mineralized and that the current structural geometry of the gold deposits is equivalent to that at the time of their formation provided that there has been no significant post-gold orogenic overprint. Within the host volcano-sedimentary sequences at the province scale, world-class orogenic gold deposits are most commonly located in second-order structures adjacent to crustal scale faults and shear zones, representing the first-order ore-forming fluid pathways, and whose deep lithospheric connection is marked by lamprophyre intrusions which, however, have no direct genetic association with gold deposition. more specifically, the gold deposits are located adjacent to ～10°-25° district-scale jogs in these crustal-scale faults. These jogs are commonly the site of arrays of ～70° cross faults that accommodate the bending of the more rigid components, for example volcanic rocks and intrusive sills, of the host belts. Rotation of blocks between these accommodation faults causes failure of more competent units and/or re

关键词： Structural geometry Tectonic history Fluid pathways Orogenic gold deposits Exploration criteria

Wild dogma II： The role and implications of wild dogma for wild dog management in Australia

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Current Zoology 2011年第6期57卷 737-740页

作者： Benjamin L. ALLEN richard m. ENGEmAN Lee R. ALLEN The University of Queensland School of Animal Studies Warrego Highway Gatton QLD 4343 National Wildlife Research Centre 4101 l_aPorte Avenue Fort Collins CO 80521-2154 USA. Richard.M.Engeman@aphis.usda.gov Biosecurity Queensland Robert Wicks Pest Animal Research Centre Tor Street Toowoomba QLD 4350. Lee.Allen@ deedi.qld.gov.au

The studies of Allen （2011） and Allen et al. （2011） recently examined the methodology underpinning claims that dingoes provide net benefits to biodiversity by suppressing foxes and cats. They found most studies to have design flaws and/or observational methods that preclude valid interpretations from the data, describing most of the current literature as ＇wild dogma＇. In this short supplement, we briefly highlight the roles and implications of wild dogma for wild dog management in Australia. We discuss nomenclature, and the influence that unreliable science can have on policy and practice changes related to apex predator management

关键词： Apex predator Canis lupus dingo Practice change Public perceptions Wild dog management

A Fractional Drift Diffusion model for Organic Semiconductor Devices

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Computers, materials & Continua 2021年第10期69卷 237-266页

作者： Yi Yang Robert A.Nawrocki richard m.Voyles Haiyan H.Zhang School of Engineering Technology Purdue UniversityWest Lafayette47906USA

Because charge carriers of many organic semiconductors(OSCs)exhibit fractional drift diffusion(Fr-DD)transport properties,the need to develop a Fr-DD model solver becomes more ***,the current research on solving the governing equations of the Fr-DD model is practically *** this paper,an iterative solver with high precision is developed to solve both the transient and steady-state Fr-DD model for organic semiconductor *** Fr-DD model is composed of two fractionalorder carriers(i.e.,electrons and holes)continuity equations coupled with Poisson’s *** treating the current density as constants within each pair of consecutive grid nodes,a linear Caputo’s fractional-order ordinary differential equation(FrODE)can be produced,and its analytic solution gives an approximation to the carrier *** convergence of the solver is guaranteed by implementing a successive over-relaxation(SOR)mechanism on each loop of Gummel’s *** on our derivations,it can be shown that the Scharfetter–Gummel discretization method is essentially a special case of our *** addition,the consistency and convergence of the two core algorithms are proved,with three numerical examples designed to demonstrate the accuracy and computational performance of this ***,we validate the Fr-DD model for a steady-state organic field effect transistor(OFET)by fitting the simulated transconductance and output curves to the experimental data.

关键词： Fractional drift diffusion model Gummel’s iteration Caputo’s fractional-order ordinary differential equation organic field effect transistor

Effects of motivation and Demography on the Quantitative Plausibility of the Trojan Horse Defence Against Possession of Child Pornography

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Journal of Harbin Institute of Technology(New Series) 2014年第6期21卷 9-15页

作者： richard E Overill Jantje A m Silomon Kam-Pui Chow Hayson Tse Dept.of Informatics King's College LondonLondon WC2R 2LSUnited Kingdom Dept.of Computer Science University of Hong Kong

The Enhanced Complexity model( ECm) developed previously has been further extended to produce a motivationally Enhanced Complexity model( mECm) which enables the degree of motivation,capability and opportunity of a hypothetical Trojan Horse author to be included in quantifying the relative plausibility of competing explanations for the existence of uncontested digital *** new model has been applied to the case of the Trojan Horse defence( THD) against the possession of child *** results demonstrate that the THD in this case cannot be plausibly sustained unless it can be shown that an ‘off-theshelf'( OTS) Trojan Horse for this task is available and it is not detectable by the target computer,at the material time.

关键词： Trojan Horse defence child pornography digital forensic evidence complexity quantitative plausibility metrics posterior odds