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FRACTAL INVESTIgATION OF THE MICROSTRUCTURE IN Alnico8 THERMOMAgNETICALLY TREATED

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Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 932-936页

作者： Fei, w.D. Chu, w.g. Yang, D.Z. Harbin Inst of Technology Harbin China

Fe-Co rich particles in the Alnico8 samples thermomagnetically treated for various times at 800 °C have been found to be of self-similarity and of fractal characteristics both in two-dimensional space and three-dimensional space. Fe-Co rich particles for 1.5, 3 and 5 min treatment have also shown a different fractal nature both in two-dimensional space and three-dimensional space as compared with the case for 10 min, which implies that Fe-Co rich particles evolve through different kinetic mechanisms. The fractal dimensions for 1.5, 3 and 5 min as well as 10 min treatment derived from the SAXS data in three-dimensional space are in agreement with the theoretical dimensions for two models introduced respectively. The fractal dimensions in two-dimensional space greater than the theoretical ones for two models can be attributed to the strong anisotropy of Fe-Co rich particle evolution in three-dimensional space.

关键词： Fractals Magnetization Microstructure Thermal effects Three dimensional Two dimensional

Effects of Root growth of Deep and Shallow Rooting Rice Cultivars in Compacted Paddy Soils on Subsequent Rice growth

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Rice science 2023年第5期30卷 459-472,I0022-I0024页

作者： Md.Dhin ISLAM Adam H.price Paul D.HALLETT School of Biological Sciences University of AberdeenSt Machar DrAberdeen AB243UUthe United Kingdom Faculty of Agriculture Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur-1706Bangladesh

Rice is often grown as multiple seasons in one year,alternating between flooded and upland systems.A major constraint,introduced from the flooded system,is a plough pan that may decrease rooting depth and productivity of follow-on upland *** penetrating the plough pan under flooded rice system can leave a legacy of weaker root growth *** rooting rice cultivars could have a bigger impact,but no direct evidence is *** explore whether a deep rather than a shallow rooting rice cultivar grown in a flooded cropping cycle benefited deeper root growth of follow-on rice in an upland,reduced tillage cropping cycle,a simulated flooded paddy in greenhouse was planted with deep(Black gora) and shallow(IR64) rooting cultivars and a plant-free *** plough pans were made in between the topsoil and subsoil to form different treatments with no plough pan(0.35 MPa),soft plough pan(1.03 MPa) and hard plough pan(1.70 MPa).After harvest of this ‘first season’ rice,the soil was drained and undisturbed to simulate zero-tillage upland and planted rice cultivar BRRI Dhan *** overall root length density(RLD),root surface area,the numbers of root tips and branching of BRRI Dhan 28 did not vary between plough pan and no plough pan *** with the shallow rooting rice genotype,the deep rooting rice genotype as ‘first season’ crop produced 19% greater RLD,34% greater surface area and 29% more branching of BRRI Dhan 28 in the *** the topsoil,however,BRRI Dhan 28 had 28% greater RLD,35% greater surface area and 43% more branching for the shallow rather than deep rooting genotype planted in the ‘first season’.The results suggested that rice cultivar selection for a paddy cycle affects root growth of a follow-on rice crop grown under no-till,with benefits to subsoil access from deep rooting cultivars and topsoil proliferation for shallow rooting cultivars.

关键词： plough pan root growth biopores crop rotation Oryza sativa preceding crop zero-tillage

On the road towards the global analysis of human synapses

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Neural Regeneration Research 2017年第10期12卷 1586-1589页

作者： g.Aleph Prieto Carl w.Cotman Institute for Memory Impairments and Neurological Disorders University of CaliforniaIrvineCAUSA

Synapses are essential units for the flow of information in the *** the last 70 years,synapses have been widely studied in multiple animal models including worms,fruit flies,and *** comparison,the study of human synapses has evolved significantly slower,mainly because of technical ***,three novel methods allowing the analysis of molecular,morphological,and functional properties of human synapses may expand our knowledge of the human ***,we briefly describe these methods,and evaluate how the information provided by each unique approach may contribute to the functional and anatomical analysis of the synaptic component of human brain *** particular,using tissue from cryopreserved human brains,synaptic plasticity can be studied in isolated synaptosomes by fluorescence analysis of single-synapse long-term potentiation（FASS-LTP）,and subpopulations of synapses can be thoroughly assessed in the ribbons of brain tissue by array tomography（AT）.Currently,it is also possible to quantify synaptic density in the living human brain by positron emission tomography（PET）,using a novel synaptic ***,data provided by FASS-LTP,AT,and PET may significantly contribute to the global understanding of synaptic structure and function in both healthy and diseased human brains,thus directly impacting translational research.

关键词： fluorescence analysis of single-synapse long-term potentiation array tomography positron emission tomography synaptosomes flow cytometry microscopy [11C]UCB-J[(R)-1-((3-(11C-methyl-11C)pyridin-4-yl)methyl)-4-(3 4 5-trifluorophenyl)pyrrolidin-2-one]

Effect of Sulfate on Adsorption of Zinc and Cadmium by Variable Charge Soils *1

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Pedosphere 1998年第3期8卷 245-250页

作者： ZHANggANgYA g．w．BRUMMER 等 InstituteofSoilScience theChineseAcademyofSciencesP.O.Box821Nanjing210008（China） DepartmentofsoilSc

SO 4 2- and Zn 2+ or Cd 2+ were added to three variable charge soils in different sequences. In one sequence sulfate was added first, and in the other, Zn 2+ or Cd 2+ ... 详细信息

SO 4 2- and Zn 2+ or Cd 2+ were added to three variable charge soils in different sequences. In one sequence sulfate was added first, and in the other, Zn 2+ or Cd 2+ first. The addition of sulfate to the system invariably caused an increase in adsorption of the heavy metal added, with the effect more remarkable when the soil reacted with the sulfate prior to the metal. The shift in pH 50 for both Zn and Cd adsorption was also comparatively larger in the first sequence of reactions. It was suggested that the increase in negative charge density and the resultant negative potential of the soil were the primary cause of the pronounced effect of sulfate on adsorption of Zn or Cd, and the formation of the ternary surface complex S SO 4 M might also play a role in the effect.

关键词： adsorption cadmium sulfate variable charge soil,zinc

The evolutionary consequences of selfish genetic elements

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Current Zoology 2016年第6期62卷 655-658页

作者： Anna K. LINDHOLM Tom A.R. price Department of Evolutionary Biology and Environmental Studies University of Zurich Winterthurerstrasse 190 Zurich Switzerland Institute of Integrative Biology University of Liverpool Crown Street Liverpool UK

The traditional view of the genome was once that it is broadly cooperative, with all genes working together amicably to improve the success of the individual as a whole. Benefits to the individual, after all, benefit all the component genes, as fair Mendelian inheritance ensures that all the genes and alleles a parent carries are equally likely to be inherited by an offspring. However, more detailed studies of inheritance have shown that this rosy view of cooperation within the genome is untrue. Instead, many genes act selfishly, manipulating gametogenesis to bias transmission in their favor （Butt and Trivers 2006）. This increases their representation in offspring at a cost to the fitness of the individual and the cooperative genes.

关键词：遗传因素进化基因组孟德尔遗传等位基因合作多基因后代

Petrochemical Comparison of 3.5 ga Old Mafic Amphibolite Inclusions from Eastern Hebei Province with Archean Mafic-ultramafic Supracrustais of Uncertain Antiquity,Southern Jilin Eastern Liaoning Provinces,China

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Chinese Journal Of geochemistry 1989年第2期8卷 97-111页

作者： w.g.Ernst Institute of geophysics and Planetary Physics Department of Earth and Space Sciences University of California Los Angeles California 90024-1567

New major element data for coexisting minerals and bulk-rock REE analyses,combined with previously obtained petrologic/geologic information,allow comparison of Archean mafic-ultramafic meta-igneous rocks from adjacent portions of northeastern Sino-Korean shield .Isotope data published by previous workers document an Early Archean age of formation for metabasaltic rocks now occurring as mafic amphibolite inclusions in tonalitic gneisses west of Bohai Bay(area).Mafic-ultramafic mineral assemblages developed in tonalitic gneisses west of Bohai Bay(areaA).Mafic-ultramafic mineral assemblages developed in amphibolite facies Archean supracrustals east of Bohai Bay(areaB)are chemically similar ,but pre-existing phase associations have been overprinted by the effects of several later metamorphic ***0peridotitic area B protoliths appear to be more magnesian ,averaging-12wt.%MgO(versus-7wt.%for area A),and are slightly less fractionated in REE concentrations relative to chondrites(La-Lu=30-8X versus 37-14X for area A),thus perhaps being more mantle-like than area A metabasaltic *** basaltic-komatiitic series east of Bohai Bay probably represents the most ancient crust of that region,being invaded by Archean tonalities,which were subsequently converted to *** observations are compatible with the hypothesis that ,similar to area A metabasaltic rocks now found as amphibolitic inclusions in orthogneisses,are B mafic supracrustals were formed during Early of Middle Archean time ,prior to widespread isofacial amphibolite facies metamorphism(600-700℃,5-7kb,low αH2O).

关键词：岩石化学辽宁河北闪岩包裹体太古代铁镁质超基性岩地质构造

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn J.w.So Konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa gordon gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

ELECTROANALYTICAL APPLICATIONS OF CARBOXYL-MODIFIED CARBON NANOTUBE FILM ELECTRODES

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 289-294页

作者： C.g.Hu w.L.wang K.J.Liao w.Zhu DepartmentofAppliedPhysics ChongqingUniversityChongqing400044China KeyLaboftheEducationMinistryforPhotoelectricTechnologyandSystem ChongqingUniversityChongqing400044China DepartmentofChemistry ChongqingUniversityChongqing400044ChinaManuscriptreceived25November2002

The electrochemical behavior of a carboxyl-modified carbon nanotube films was investigated to explore its possibility in electroanalytical applicaton. Cyclic voltammetry of quinone was conducted in 1mol/L Na2SO4, which showed a stable, quasi-reversible voltammetric response for quinone / hydroquinone, and the anodic and the cathodic peak potentials were 0.657V and -0.029V (vs. SCE) at a scan rate of 0.1V.s-1, respectively. Both anodic and cathodic peak currents depended linearly on the square root of the scan rate over the range of 0.01-0.5V.s-1, which suggested that the process of the electrode reactions was diffusion-controlled. Carboxyl-modified carbon nanotube electrodes made it possible to determine low level of dopamine selectively in the presence of a large excess of ascorbic acid in acidic media using derivative voltammetry. The results obtained were discussed in details. This work demonstrates the potential of carboxyl-modified carbon nanotube electrodes for electroanalytical applications.

关键词： carbon nanotube electrochemistry carboxyl modification dopamine

A risk table to address concerns external to stock assessments when developing fisheries harvest recommendations

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Ecosystem Health and Sustainability 2020年第1期6卷 46-56,45页

作者： Martin w.Dorn Stephani g.Zador Resource Ecology and Fisheries Management Alaska Fisheries Science CenterSeattleWAUSA

This paper develops a risk table to facilitate incorporation of additional information into the fisheries stock assessment and management *** risk table is designed to evaluate unanticipated ecosystem and environmental impacts on marine resources that may require a rapid management *** risk table is a standardized framework to document concerns about the assessment model,population dynamics,and the ecosystem/environment that are not explicitly addressed within the stock assessment model.A scoring procedure is used to evaluate the severity of the *** concerns can then be evaluated in support for or against a reduction from the maximum Acceptable Biological Catch while providing reviewers and stakeholders transparent documentation of the *** risk table was applied successfully to several stocks on a trial basis during the 2018 groundfish assessment cycle for the North Pacific Fishery Management Council,and will be used for all full groundfish assessments in *** changes in climate are likely for Alaska marine ecosystems in coming decades,and these changes are not entirely ***,we avocate that the risk table approach should be included in the suite of management tools used to address the effects of climate change on Alaska marine resources.

关键词： Acceptable biological catch ecosystem-based management risk assessment stock assessment North Pacific Fishery Management Council