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characteristics of Phosphorus in Some Eastern Australian Acid Sulfate Soils

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Pedosphere 2002年第3期12卷 229-234页

作者： c. LINSchool of Environmental Science and Management, Southern cross University, Lismore, NSW (Australia) School of Environmental Science and Management Southern Cross University Lismore NSW 澳大利亚

Forty-five acid sulfatc topsoil samples (depth < 0.5 m) from 15 soil coreswere collected from 11 locations along the New South Wales coast, Australia. There was an overalltrend for the concentration of the Hcl-extract... 详细信息

Forty-five acid sulfatc topsoil samples (depth coreswere collected from 11 locations along the New South Wales coast, Australia. There was an overalltrend for the concentration of the Hcl-extractable P to increase along with increasing amounts oforganic c and the Hcl-extractable trivalent metals in the topsoils of some less-disturbed acidsulfate soils (pH c P in these soils probably accumulated viabiological cycling and was retained by complexation with trivalent metals or their oxides andhydroxides. While there was no clear correlation between pH and the water-extractable P, theconcentration of the water-extractable P tended to increase with increasing amounts of theHcl-extractable P. This disagrees with some established models which suggest that the concentrationof solution P in acid soils is independent of total P and decreases with increasing acidity. Thehigh concentration of sulfate present in acid sulfate soils appeared to affect the chemical behaviorof P in these soil systems. comparison was made between a less disturbed wetland acid sulfate soiland a more intensively disturbed sugarcane acid sulfate soil. The results show that reclamation ofwetland acid sulfate soils for sugarcane production caused a significant decrease in theHcl-extractable P in the topsoil layer as a result of the reduced bio-cycling of phosphorusfollowing sugarcane farming. Simulation experiment shows that addition of hydrated lime had noeffects on the immobilization of retained P in an acid sulfate soil sample within a pH range3.5～4.6. When the pH was raised to above 4.6, soluble P in the soil extracts had a tendency toincrease with increasing pH until the 15th extraction (pH 5.13). This, in combination with the poorpH-soluble P relationship observed from the less-disturbed acid sulfate soils, suggests that solubleP was not clearly pH-dependent in acid sulfate soils with pH < 4.5.

关键词： acid sulfate soil acidity phosphorus

Fundamental statistics for the behavioral sciences David c. Howell. 4th ed

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Structural analysis Russell c. Hibbeler. 5th ed.

1999年

作者： David c. Howell.

来源：畅想之星图书光盘版（南... 评论

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Steady State creep Rate Equation of Inconel 718 Superalloy

2002年

作者： Russell c. Hibbeler.

来源：畅想之星图书光盘版（南... 评论

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Journal of Materials Science & Technology 1989年第2期5卷 79-84页

作者：韩雅芳 M.c.chaturvedi Institute of Aeronautical Materials Beijing China. Department of Mechanical Engineering University of Manitoba Canada.

The steady state creep rate equdtion of a nickel base superalloy Inconel 718, strengthened by coherent ordered disc-shaped bct γ^(11) phase and coherent spherical fcc γ~1 phase precipitates, has been established in the stress and temperature ranges of 620-840 MN m^(-2) and 853-943K, respecti- vely. constant stress tensile creep tests were used to medsure the values of steady state creep rate, ε_s, and the consecutive stress reduction method was used to measure the back stress during creep deformation. The values of effective stress exponent, n_e, were detemined from the slopes of the lgε_s vs. lg(σ_a-σ_0)/G plots. The effect of grain size, d, on steady state creep rdte has been also studied in this investigation, and the grain size sensitive exponents m were detemined from the slopes of lgε_s vs. lg(b/d) plots. The creep rate equations of Inconel 718, in the above stress and temperature ranges, have been proposed to be ε_s=1.6×10^(-5)(D_1Gb/KT) (b/d )^(0.19)[(σ_a-σ_0)/G]^(1.35) in diffusional creep region, and ε_s =75(D_1Gb/KT) (b/d)^(-0.42)[(σ_a-σ_0)/G]^(5.5) in dislocation power law creep region.

关键词： Inconel 718 steady state creep creep rate equation

Genomic surveillance of Nevada patients revealed prevalence of unique SARS-coV-2 variants bearing mutations in the RdRp gene

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Journal of Genetics and Genomics 2021年第1期48卷 40-51页

作者： Paul D.Hartley Richard L.Tillett David P.Aucoin Joel R.Sevinsky Yanji Xu Andrew Gorzalski Mark Pandori Erin Buttery Holly Hansen Michael A.Picker cyprian c.Rossetto Subhash c.Verma Nevada Genomics center RenoNV 89557USA University of Nevada RenoRenoNV 89557USA Nevada Institute of Personalized Medicine University of NevadaLas VegasNV 89154USA Department of Microbiology&Immunology University of NevadaReno School of MedicineRenoNV 89557USA Theiagen consulting LLCHighlands RanchCO 80128USA Nevada center for Bioinformatics RenoNV 89557USA Nevada State Public Health Laboratory RenoNV 89503USA Southern Nevada Public Health Laboratory of the Southern Nevada Health District Las VegasNV 89107USA

Patients with signs of cOVID-19 were tested through diagnostic RT-PcR for SARS-coV-2 using RNA extracted from the nasopharyngeal/nasal *** determine the variants of SARS-coV-2 circulating in the state of Nevada,specimens from 200 cOVID-19 patients were sequenced through our robust sequencing platform,which enabled sequencing of SARS-coV-2 from specimens with even very low viral loads,without the need of culture-based *** genome coverage allowed the identification of single and multi-nucleotide variants in SARS-coV-2 in the community and their phylogenetic relationships with other variants present during the same period of the *** report the occurrence of a novel mutation at 323aa (314aa of orf1b) of nsp12 (RNA-dependent RNA polymerase) changed to phenylalanine(F) from proline (P),in the first reported isolate of SARS-coV-2,*** 323F variant was present at a very high frequency in Northern *** modeling determined this mutation in the interface domain,which is important for the association of accessory proteins required for the *** conclusion,we report the introduction of specific SARS-coV-2 variants at very high frequency in distinct geographic locations,which is important for understanding the evolution and circulation of SARS-coV-2variants of public health importance,while it circulates in humans.

关键词： SARS-coV-2 cOVID-19 Genome enrichment nsp12 RdRp orf1b 314

Ti-47Al-2Mn-2Nb合金低温静态和动态拉伸性能及硼的影响

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金属学报 1999年第11期35卷 1139-1143页

作者：王瑜林栋梁周元鑫夏源明 c.c.Law 上海交通大学材料科学系教育部高温材料及高温测试开放实验室上海200030 中国科学技术大学近代力学系合肥230026 MaterialsandMechanicsEngineering UnitedTechnologiesCompany-Pratt&Whittney400MainStreetEastHartford

用常规拉伸和Ｈｏｐｋｉｎｓｏｎ拉杆技术，研究具有近全片层组织形变Ｔｉ－４７ＡＩ－ＺＭｎ－２Ｎｂ合金１８０Ｋ下静态（１０－５──１０－１ｓ－１）和动态（２０－１０３ｓ－１）拉伸性能及其受硼的影响，发现Ｔｉ－４７ＡＩ－２... 详细信息

用常规拉伸和Ｈｏｐｋｉｎｓｏｎ拉杆技术，研究具有近全片层组织形变Ｔｉ－４７ＡＩ－ＺＭｎ－２Ｎｂ合金１８０Ｋ下静态（１０－５──１０－１ｓ－１）和动态（２０－１０３ｓ－１）拉伸性能及其受硼的影响，发现Ｔｉ－４７ＡＩ－２Ｍｎ－２Ｎｂ和Ｔｉ－４７ＡＩ－２Ｍｎ－２Ｎｂ－１Ｂ合金１８０Ｋ下的拉伸强度均比室温高，静态（１０－５──１０－１ｓ－１）时与应变速率之间呈单对数线性关系，动态（１０—１０３ｓ－１）时呈线性关系．１．０Ｂ原子分数，％）仍能明显提高合金的静态和动态拉伸强度，但对拉伸塑性和断裂方式影响不大。

关键词： TiAl合金硼低温拉伸性能钛合金

Urban Development of Macao:challenges and Opportunities

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china city Planning Review 2016年第1期25卷 68-75页

作者： Roger c.K.chan Li caige Department of Urban Planning and Design University of Hong Kong Faulty of Architecture University of Hong Kong

This paper reviews the socio-economic development and the spatial evolution patterns of Macao. It argues that urbanization and intense land development have posed three challenges to Macao's future development pathway, namely, limited provision of resource, lack of diversification ofindustries, and incomplete planning legislation. The General Agreement on the cooperation between Guangdong and Macao signed in 2003 represents a strong policy incentive that offered a comprehensive institutional framework to promote economic integration. The Agreement is conducive to achieving economic development through proposing dynamic and diversified economic activities, which will also benefit tourism. The development of Hengqin will serve as a test bed for furthering the implementation of "one country, two systems" constitutional principle, which will also improve the existing regional cooperation mechanisms. A comprehensive urban planning system should be established to avoid marginalization in regional development. Better reallocation of resources and prevention of over-competition in the market are two critical components in achieving sustainable development of Macao.

关键词： planning regional integration Macao

Rectifying barrier at GaN/Sic hetero-junction studied with positron annihilation spectroscopy

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chinese Physics B 2005年第11期14卷 2293-2299页

作者：胡一帆 Beling c D Department of Physics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics University of Hong Kong Hong Kong China

Positron annihilation spectroscopy on GaN films grown on Sic substrate with MBE are presented. It is shown that the GaN/Sic interface is rectifying towards positrons, such that positrons can only travel from Sic to GaN and not vice versa. Potential steps seen by the positron at the GaN/Sic interface are calculated from experimental values of electron and positron work function. This “rectifying” effect has been successfully mimicked by inserting a thin region of very high electric field in the Variable Energy Positron Fit （VEPF） analysis. The built-in electric field is attributed to different positron affinities, dislocation and/or interface defects at the GaN/Sic interface.

关键词： GaN Sic hetero-junction positron rectifying barrier

Delmar's Fundamentals of anatomy & physiology / Donald c. Rizzo.

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