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Journal of Bionic Engineering 2023年第5期20卷 1967-1984页

作者： Şefika Kasman İbrahim Can uçar Sertan Ozan Department of Mechanical Engineering Dokuz Eylul UniversityIzmir35397Turkey Department of Mechanical Engineering Yozgat Bozok UniversityYozgat66100Turkey

This study presents a comprehensive approach to applying texturing processes created by engraving on the surface of CoCr28Mo alloy workpieces using a 20 W pulsed nanosecond fiber *** hatch strategy and distance,frequency,and scan speed were control parameters for texturing *** effectiveness of the parameters in terms of roughness and contact angle of the texturized surface was *** roughness and contact angle were analyzed using variance analysis to identify each variable's *** has been determined that the roughness of the texture defined by the hatch strategy plays a decisive role in the wettability behavior of the surface;however,the scan speed,frequency,and hatch distance which are among the laser surface texturing conditions are influential in the roughness and contact *** scan speed and hatch distance while decreasing frequency resulted in smoother surfaces,increasing the contact *** having rough surfaces produced with different processing conditions exhibit a super hydrophilic *** contact angle is most sensitive to the hatch distance;however,the frequency has the least influence on the contact *** most and least efficient surface roughness parameters are revealed to be scan speed and hatch distance,respectively.

关键词： Laser surface texturing Co-Cr-Mo alloy Surface roughness Wettability Bionic

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

The Design of the M-B-Quadro Optical Switch and Its Access Control Strategies

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光学学报 2003年第S1期23卷 729-730页

作者： Ho-Ting Wu, Wang-Rong ChangDept. of Computer Science and Information Engineering, Taipei u. of Technology, 1 Sec.3, Chung Hsiao E. Rd., Taipei, 106, Taiwan Dept. of Computer Science and Information Engineering Taipei U. of Technology1 Sec.3 Chung Hsiao E. Rd. Taipei 106 Taiwan

This paper proposes a new simple contention resolution switching architecture, M-B-Quadro, and its underlying access control strategies. By incorporating delay and buffer lines, the switching node can effectively obta... 详细信息

关键词： Access on of Design into for VSC 一弓 node than WDM

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

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

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.

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

Approximation properties for the genuine modi ed Bernstein-Durrmeyer-Stancu operators

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Applied Mathematics(A Journal of Chinese universities) 2020年第4期35卷 468-478页

作者： CAI Qing-bo ulku Dinlemez Kantar Bayram Cekim School of Mathematics and Computer Science Quanzhou Normal UniversityQuanzhou 362000China Department of Mathematics Faculty of ScienceGazi UniversityBesevler AnkaraTurkey

In this paper,we study on the genuine modified Bernstein-Durrmeyer-Stancu operators Gn(f,x)and investigate some approximation properties of ***,we present a Voronovskaja type theorem for these *** also give some graph... 详细信息

关键词： genuine modi ed Bernstein-Durrmeyer-Stancu operators Voronovskaja type approximation theorem rate of convergence modulus of continuity