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Relationship between magnetic parameters and heavy element contents of arable soil around a steel company,Nanjing

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Science China Earth Sciences 2010年第3期53卷 411-418页

作者： BLAHA u ROESLER W APPEL E Institute for Geosciences University of Tübingen

Magnetic parameters and element contents were determined in core NJ008 collected from the uppermost ca. 40 cm in a steel company in southwest Nanjing. the results showed that magnetic susceptibility (χ), saturation isothermal remanent magnetization (SIRM) and anhysteretic remanent magnetization (ARM) were enhanced in the uppermost 20 cm, with a mean magnetic susceptibility value of 112.5×10-8 m3 kg-1. Below 20 cm, χ decreased sharply with a mean value of 27.8×10-8m3 kg-1. Low-coercivity minerals such as magnetite dominate in arable soils, while the relative content of antiferromagnetic minerals increases below 20 cm. Heavy metals (Ni, Cu, Fe, Pb, V, and Zn) have similar vertical trends as χ. Principal component analysis reveals common high loadings of the same factor for magnetic concentration parameters (χ, ARM, and SIRM) and elements (Ni, Cu, Fe, Pb, V, and Zn) with an excellent linear correlation (0.69≤R≤0.98) between them. Magnetic susceptibility of paddy soil core NJ013, which had the same parent material as NJ008 but was far from pollution sources, showed stable values of magnetic concentration parameters along the whole core. Absolute values correspond to the so-called magnetic background value (below 20 cm) of NJ008. this indicates that pesticide and fertilizer had little effect on magnetic signals of the upper part of core NJ008 and the extremely enhanced magnetic concentration parameters originate from the steel company emission. Although, the arable soil does not reveal the pollution history and transportation due to annual ploughing, the significant linear relationship between magnetic concentration parameters and heavy metal contents suggests that magnetic parameters can serve as a proxy for quickly detecting soil metallic pollution and estimating the extent of contamination.

关键词： steel company soil heavy metal magnetic parameters

ASYMMEtRIC SYNtHESIS——ENANtIOSELECtIVE SYNtHESIS OF (R)-α-AMINO ACIDS uSING L-ISOLEuCINE AS CHIRAL AuXILIARY REAGENt

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Science China Chemistry 1984年第6期27卷 566-571页

作者：蒋耀忠,u.SCHLLKOPF,u.GROtH Chengdu Institute of Organic Chemistry Academia Sinica Institute of Organic Chemistry Gottingen university Federal Republic of Germany Institute of Organic Chemistry Gottingen university Federal Republic of Germany

Enantioselective synthesis of (R)-α-amino acids via heterocyclic intermediate-(3S)-2,5-dimethoxy-3-see-butyl-3, 6-dihydropyrazine (5), using L-isoleucine as chiral auxiliaryreagent and glycine as raw meterial, has been studied. the alkylation of compound 5 withbutyllithium affords its lithium derivative (6) according to the cardanion mechanism. then 6reacts with alkyl halide RX (7) to give the alkylated products (8) with very high diastereo-selectivity. In this reaction, the group R of 7 enters trans to the see-butyl group at C-3, i. *** (R)-configuration is induced at C-6 of 8. After hydrolysis the (R)-α-amino acid methylesters (9) are obtained.

关键词： OCH HZ ASYMMEtRIC SYNtHESIS ENANtIOSELECtIVE SYNtHESIS OF AMINO ACIDS uSING L-ISOLEuCINE AS CHIRAL AuXILIARY REAGENt CDC HCI 占一 CHC ABX

Micro- and Nanostripes of Self-Assembled Au Nanocrystal Superlattices by Direct Micromolding

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Nano Research 2010年第8期3卷 537-544页

作者： Boya Radha Giridhar u.Kulkarni Chemistry and Physics of Materials unit and DSt.unit on Nanoscience Jawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.O.Bangalore 560064India

A simple,inexpensive direct micromolding method for patterning Au nanocrystal superlattices using a polydimethylsiloxane(PDMS)stamp has been *** method involves in situ synthesis of Au(I)dodecanethiolate and its decomposition leading to Au nanocrystals in the microchannels of the stamp which order themselves to form patterned superlattice stripes,in conformity with the stamp *** to its insolubility in common solvents,the dodecanethiolate was made by reacting Au(PPh3)Cl and dodecanethiol in situ inside the microchannels,by injecting first the former solution in toluene at room temperature followed by the thiol solution at 120°*** the reaction mixture at 250°C,resulted in formation of nanocrystals(with a mean diameter of 7.5 nm)and hexagonal *** using an external pressure while molding,parallel stripes with sub-100 nm widths were *** choice of parameters such as injection temperature of the thiol and concentrations is shown to be important if an ordered superlattice is to be *** addition,these parameters can be varied as a means to control the nanocrystal size.

关键词： nanolithography soft lithography metal nanocrystal superlattice micromolding direct patterning

Ecological variation along the salinity gradient in the Baltic Sea Area and its consequences for reproduction in the common goby

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Current Zoology 2018年第2期64卷 259-270页

作者： Isabel MuCK Katja u. HEuBEL Department of Biology University of Tuibingen Auf tier Morgenstelle 28 72076 Tuibingen Germany Institute for Zoology Ecological Research Station Rees University of Cologne Grietherbusch 3a D-46459 Rees Germany tvarminne Zoological Station University of Helsinki J.A. Palmenin tie 260 10900 Hanko Finland

Although it has become clear that sexual selection may shape mating systems and drive speciation, the potential constraints of environmental factors on processes and outcomes of sexual selection are largely unexplored. Here, we investigate the geographic variation of such environmental factors, more precisely the quality and quantity of nest resources （bivalve shells） along a salinity gradient in the Baltic Sea Area （Baltic Sea, Sounds and Belts, and Kattegat）. We further test whether we find any salinity-associated morphological differences in body size between populations of common gobies Pomatoschistus microps, a small marine fish with a resource-based mat- ing system. In a geographically expansive field study, we sampled 5 populations of P. microps occurring along the salinity gradient （decreasing from West to East） in the Baltic Sea Area over 3 consecutive years. Nest resource quantity and quality decreased from West to East, and a correla- tion between mussel size and male body size was detected. Population density, sex ratios, mating- and reproductive success as well as brood characteristics also differed between populations but with a less clear relation to salinity. With this field study we shed light on geographic variation of distinct environmental parameters possibly acting on population differentiation. We provide insights on relevant ecological variation, and draw attention to its importance in the framework of context-dependent plasticity of sexual selection.

关键词： aquatic ecology body size environmental gradient nest availability nesting resources sexual selection.

Facet selective etching of Au microcrystallites

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Nano Research 2015年第9期8卷 2925-2934页

作者： Gangaiah Mettela and Giridhar u. Kulkarni thematic unit of Excellence on Nanochemistry and Chemistry and Physics of Materials unit Jawaharlal Nehru Centre for AdvancedScientific Research (JNCASR) Jakkur P.O. Bangalore 560 064 India

High-symmetry crystals exhibit isotropic properties. Inducing anisotropy, e.g., by facet selective etching, is considered implausible in face-centered cubic （FCC） metals, particularly gold, which, in addition to being an FCC, is noble. We report for the first time the facet selective etching of Au microcrystals obtained in the form of cuboctahedra and pentagonal rods from the thermolysis of a gold- organic precursor. the selective etching of {111} and {100} facets was achieved using a capping method in which tetraoctylammonium cations selectively cap the {111} facets while Br- ions protect the {100} facets. the exposed facets are oxidized by O2/C1-, yielding a variety of interesting geometries. the facet selective etching of the Au microcrystallites is governed only by the nature of the facets; the geometry of the microcystallite does not appear to play a significant role. the etched surfaces appear rough, but a closer examination reveals well-defined corrugations that are indexable to high hkl values. Such surfaces exhibit enhanced Raman activity.

关键词： gold,microcrystallites,facet selective eapping

新疆西南天山木扎尔特河一带低压泥质麻粒岩岩石学特征、独居石u-th-Pb定年及其地质意义

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岩石学报 2009年第9期25卷 2271-2280页

作者：苟龙龙张立飞 G0u Peking univ Key Lab Orogen Belts & Crustal Evolut Minist Educ Sch Earth & Space Sci Beijing 100871 Peoples R China

古南天山洋闭合过程中,由于洋壳俯冲产生的岛弧岩浆作用加热大陆地壳,在新疆西南天山木扎尔特一带形成了一套低压高温泥质麻粒岩相变质岩石。本文用theriak-Domino热力学软件对该套岩石中的堇青石榴夕线石黑云母片麻岩和含夕线石堇青石... 详细信息

古南天山洋闭合过程中,由于洋壳俯冲产生的岛弧岩浆作用加热大陆地壳,在新疆西南天山木扎尔特一带形成了一套低压高温泥质麻粒岩相变质岩石。本文用theriak-Domino热力学软件对该套岩石中的堇青石榴夕线石黑云母片麻岩和含夕线石堇青石榴黑云母片麻岩进行了岩石学相平衡计算研究,得到它们峰期变质的温压条件分别是:t=630～674℃,P=5.2～5.5kbar和t=645～684℃,P=5.4～5.7kbar。并采用独居石th-u-Pb电子探针定年方法,对样品WQ006中的3颗独居石进行了原位年龄测定(38个分析点),得到2组等时线年龄,分别是376±8Ma和280±8Ma(2σ)。结合独居石的岩相学特征,提出了新疆西南天山低压高温麻粒岩相峰期变质作用的时代为280±8Ma,而376±8Ma(2σ)可能为原沉积岩的原岩/成岩年龄。表明西南天山洋壳开始俯冲发生在晚古生代,进一步证明了西南天山造山带俯冲碰撞发生在晚二叠纪之后的观点。

关键词：新疆西南天山木扎尔特低压泥质麻粒岩相岩石学特征独居石定年地质意义 southwestern tianshan region monazite dating China South tianshan 黑云母片麻岩 electron microprobe 南天山洋峰期变质 phase equilibria

the Effect of Fibre Length on Flexural and Dynamic Mechanical Properties of Pineapple Leaf Fibre Composites

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Journal of Renewable Materials 2020年第7期8卷 833-843页

作者： A.A.Mazlan M.t.H.Sultan S.N.A.Safri N.Saba A.u.M.Shah M.Jawaid Department of Aerospace Engineering Faculty of EngineeringUniversiti Putra MalaysiaSerdangSelangor Darul Ehsan43400 UPMMalaysia Laboratory of Biocomposite technology Institute of Tropical Forestry and Forest Products(INTROP)SerdangSelangor Darul Ehsan43400 UPMMalaysia Aerospace Malaysia Innovation Centre(944751-A) Prime Minister’s DepartmentMIGHT Partnership HubJalan Impact63000 CyberjayaMalaysia

the present paper deals with the effect of loading different pineapple leaf fibre(PALF)length(short,mixed and long fibres)and their reinforcement for the fabrication of vinyl ester(VE)*** of PALF/VE composites was investigated through three-point bending flexural testing and viscoelastic(dynamic)mechanical properties through dynamic mechanical analysis(DMA).DMA results revealed that the long PALF/VE composites displayed better mechanical,damping factor and dynamic properties as compared to the short and mixed PALF/VE *** flexural strength and modulus of long PALF/VE composites were 113.5 MPa and 14.3 GPa,*** storage(E′)and loss(E″)moduli increased to 2000 MPa and 225 MPa respectively for PALF/VE *** result analysis indicated that increasing the length of the reinforcement fibre results in satisfactory mechanical performance and dynamic properties of composites.

关键词： Pineapple leaf fibre vinyl ester resin flexural strength dynamical mechanical properties damping factor

Nucleon Effective Mass in Asymmetric Nuclear Matter within Extended Brueckner Approach

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Chinese Physics Letters 2012年第4期29卷 47-50页

作者： GAN Sheng-Xin ZuO Wei u.Lombardo Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 Graduate School of Chinese Academy of Sciences Beijing 100049 Department of Physics and Astrophysics Catania UniversityVia Santa Sofia 64I-95123Italy

the on-shell properties of the nucleon effective mass in asymmetric nuclear matter are investigated in the framework of an extended Brueckner-Hartree-Fock (BHF) *** proton and neutron effective masses in neutron-rich nuclear matter are predicted by including both the effect of ground state correlations and the threebody force (tBF) rearrangement *** this framework,the neutron effective mass is predicted *to be larger than the proton one in neutron-rich nuclear matter,i.e.,m*n ≥ m**** effect of ground state correlations turns out to be dominated at low densities and it leads to a strong enhancement of the effective *** tBF rearrangement contribution becomes predominant over the effect of ground state correlations at high densities and it reduces remarkably the absolute magnitude of the isospin splitting of the neutron and proton effective masses in neutron-rich matter at high densities.

关键词： rearrangement absolute Hartree

Multiple drug resistance and bacterial infection

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Asian Pacific Journal of tropical Medicine 2008年第2期1卷 76-82页

作者： Asad u Khan Interdisciplinary Biotechnology unit Aligarh Muslim UniversityAligarh 202002India

Drug resistance is becoming a great problem in developing countries due to excessive use and misuse of antibiotics. the emergence of new pathogenic strains with resistance developed against most of the antibiotics which may cause,difficult to treat *** understand the current scenario in different mode of infection is most important for the clinicians and medical *** article summarized some common infections and antibiotic resistance pattern found among these pathogens.

关键词： Drug resistance Bacteria Infection