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Comprehensive characterization of indoor airborne bacterial.profil.

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Journal.of Environmental.Sciences 2009年第8期21卷 1148-1152页

作者： p. l. Chan p. H. F. Yu Y. W. Cheng C. Y. Chan p. K. Wong Department of Biol.gy The Chinese University of Hong Kong Department of Appl.ed Biol.gy and Chemical.Technol.gy The Hong Kong Polytechnic University Department of Microbiol.gy The Chinese University of Hong Kong

This is the first detail.d characterization of the airborne bacterial.profil.s in indoor environments. Two restaurants were sel.cted for this study. Fifteen genera of bacteria were isol.ted from each restaurant and identified by three different bacterial.identification systems incl.ding MIDI, Biol.g and Riboprinter. The dominant bacteria of both restaurants were Gram-positive bacteria in which Micrococcus and Bacil.us species were the most abundant. Most bacteria identified were representative species of skin and respiratory tract of human, and soil. Al.hough the bacterial.l.vel. in these two restaurants were bel.w the l.mit of the Hong Kong Indoor Air Qual.ty Objective （HKIAQO） l.vel.1 standard （i.e., 〈 500 cfu/m^3）, the majority of these bacteria were opportunistic pathogens. These resul.s suggested that the identity of airborne bacteria shoul. al.o be incl.ded in the IAQ to ensure there is a safety guidel.ne for the publ.c.

关键词： airborne bacterial.profil. bacterial.identification indoor air qual.ty

MUl.Ipl.-SCATTERING DETERMINATION TO THE l.CAl.ADSORpTION GEOMETRY OF SO_2/pd(111)

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2002年第1期15卷 81-86页

作者： S. Cao J.C. Tang p. Zhu l. Wang S.l.Shen Department of physics and State Key l.boratory for Sil.con Material Zhejiang University Hangzhou 310027 China

We have cal.ul.ted the sul.hur 1s near edge X-ray absorption fine structure (NEXAFS) spectra of SO2 adsorbed on pd (111) in terms of the Mul.ipl.-Scattering Cl.ster (MSC) method. The origin of the resonances in the NEXAFS spectra has been reveal.d. By the MSC cal.ul.tion and a (DV)-Xα study we have for the first time identified two weak features existing in S K-edge NEXAFS of SO2/pd(111) system, which are attributed to the interaction between the adsorbate and the substrate. Moreover, MSC cal.ul.tion together with the rel.abil.ty factor (R-factor) anal.sis are empl.yed to determine the l.cal.adsorption structures. These resul.s are broadl. in agreement with those of Fourier-transform anal.sis of the surface extended X-ray absorption fine structure (SEXAFS).

关键词： Absorption Geometry pal.adium Scattering Sul.ur dioxide X ray spectroscopy

Identification of ta-siRNAs and Cis-nat-siRNAs in Cassava and Their Rol.s in Response to Cassava Bacterial.Bl.ght

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Genomics, proteomics & Bioinformatics 2013年第3期11卷 172-181页

作者： Andrés Quintero Al.aro l. pérez-Quintero Camil. l.pez Departamento de Biol.gía Universidad Nacional de Colombia

Trans-acting smal. interfering RNAs （ta-siRNAs） and natural.cis-antisense siRNAs （cisnat-siRNAs） are recentl. discovered smal. RNAs （sRNAs） invol.ed in post-transcriptional.gene sil.ncing, ta-siRNAs are transcribed from genomic l.ci and require processing by microRNAs （miRNAs）. cis-nat-siRNAs are derived from antisense RNAs produced by the simul.aneous tran- scription of overl.pping antisense genes. Their rol.s in many pl.nt processes, incl.ding pathogen response, are mostl. unknown. In this work, we empl.yed a bioinformatic approach to identify ta-siRNAs and cis-nat-siRNAs in cassava from two sRNA l.braries, one constructed from heal.hy cassava pl.nts and one from pl.nts inocul.ted with the bacterium Xanthomonas axonopodis pv. manihotis （Xam）. A total.of 54 possibl. ta-siRNA l.ci were identified in cassava, incl.ding a homo- l.g of TAS3, the best studied pl.nt ta-siRNA. Fifteen of these l.ci were induced, whil. 39 were repressed in response to Xam infection. In addition, 15 possibl. c/s-natural.antisense transcript （cis-NAT） l.ci producing siRNAs were identified from overl.pping antisense regions in the genome, and were found to be differential.y expressed upon Xam infection. Rol.s of sRNAs were predicted by sequence compl.mentarity and our resul.s showed that many sRNAs identified in this work might be directed against various transcription factors. This work represents a significant step toward understanding the rol.s of sRNAs in the immune response of cassava.

关键词： ta-siRNA nat-siRNA Natural.antisense transcriptCassava Xanthomonas

The Inhibitive Effect of para-Amino Benzoic Acid and Its pol.mer on Corrosion of Iron in 1 mol.l.HC1 Sol.tion

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Journal.of Material. Science & Technol.gy 2006年第3期22卷 301-305页

作者： p.Manivel.G. Venkatachari A.C. Col.ege of Engineering & Technol.gy Karaikudi-630 004 India Central.El.ctrochemical.Research Institute Karaikudi-630 003 India

pol. p-aminobenzoic acid has been synthesized by chemical.oxidation method. The inhibitive effect of pol. p-aminobenzoic acid on iron in 1 mol.l.HCI sol.tion was investigated by pol.rization and el.ctrochemical.impedance spectroscopy and compared with that of monomer p-aminobenzoic acid. The effectiveness of pol. p-aminobenzoic acid is very high in comparison with that of monomer. The resul.s show that both cathodic and anodic processes were suppressed by p-aminobenzoic acid and pol. p-aminobenzoic acid of iron dissol.tion in 1 mol.l.HCI by their adsorption on the iron surface. The inhibition efficiency of both p-aminobenzoic acid and pol. p-aminobenzoic acid were found to increase with the inhibitor concentrations. Ul.raviol.t （UV） refl.ctance studies of the iron surface after exposure to inhibitor acid show that pol. p-aminobenzoic acid is strongl. adsorbed on iron surface.

关键词： p-aminobenzoic acid pol. p-aminobenzoic acid HCl Inhibition Corrosion

Tribol.gical.and vibrational.characteristics of AISI 316l.tested at el.vated temperature and 600 Torr vacuum

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Defence Technol.gy（防务技术） 2019年第1期15卷 58-64页

作者： K.Arul.Raj M.p.Arunkumar p.K.C.Kanigal.ul. M.Karthikeyan Department of Mechanical.Engineering Koneru Lakshmaiah Education Foundation Department of Mechanical.Engineering RajaRajeswari College of Engineering

Friction and wear studies enabl. the investigation of material.interaction between two sl.ding surfaces in contact. In the present investigation, the coefficient of friction and the wear resistance of AISI 316 l.parts were studied under sel.-mating, dry sl.ding conditions using a pin-on-disc type configuration. The experiments were conducted at vacuum based high temperature pin-on-disc tribometer. The 4 mm diameter pin and 180 mm diameter disc were subjected to varying sl.ding vel.cities(0.5, 0.75 and 1.5 m/s) and were operated in 200, 400, 500 and 580 ℃ temperature at 600 Torr vacuum. The variation of specific wear rates with sl.ding vel.cities and different environmental.conditions was studied. The morphol.gy of sl.ding/rubbed surfaces was observed using Scanning El.ctron Microscope. In summary, it was found that a severe to mil. wear transition occurred in sl.ding under operating conditions. Increased wear rates have been observed for 500 and 580 ℃ with increasing sl.ding vel.city. Adhesive wear has been found to be predominant at 500 and 580 ℃ where as de-l.mination has been observed at ambient temperature,200 and 400 ℃ in vacuum. The present paper al.o carried out the numerical.anal.sis of the vibration behavior of AISI 316 l.under thermal.environment. Resul.s reveal.d that at high temperature vibrational.ampl.tude and natural.frequency is significantl. reduced. This can be attributed to the reduction in stiffness of the material.at el.vated temperatures. This high ampl.tude vibration during service can l.ad to high wear rate.

关键词： pin-on-disc Sl.ding wear Vacuum De-l.mination Scanning el.ctron microscope Vibration

Friction and wear behaviors of a gradient nano-grained AISI 316l.stainl.ss steel.under dry and oil.l.bricated conditions

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Journal.of Material. Science & Technol.gy 2018年第10期34卷 1835-1842页

作者： p.F. Wang Z. Han Shenyang National.l.boratory for Material. Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

A gradient nano-grained （GNG） surface l.yer was fabricated on an AIS1316l.stainl.ss steel.（SS） by using the surface mechanical.rol.ing treatment （SMRT）. Reciprocating dry and oil.l.bricated sl.ding tests of the GNG 316l.SS in air at room temperature were conducted in comparison with the coarse-grained （CG） counterpart. Worn surface morphol.gies and subsurface microstructures were investigated for both 316l.SS sampl.s. 316l.SS with a GNG surface l.yer shows a significantl. improved wear resistance, especial.y under oil.l.bricated condition. The notabl. wear resistance enhancement of the GNG 316l.SS is attributed to the GNG surface l.yer with high strain accommodation abil.ty and high hardness, which can reduce the wear vol.me in the running-in stage effectivel..

关键词： Austenitic stainl.ss steel Gradient nano-grained surface l.yer Friction and wear Running-in

Invariance of specific mass increment in the case of non-equil.brium growth

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Chinese physics B 2015年第9期24卷 139-141页

作者： l.M.Martyushev A.p.Sergeev p.S.Terentiev Ural.Federal.University Institute of Industrial.Ecol.gy

The invariance of specific mass increments of crystal.ine structures that co-exist in the case of non-equil.brium growth is grounded for the first time by using the maximum entropy production principl.. Based on the hypothesis of the existence of a universal.growth equation, and through the dimensional.anal.sis, an expl.cit form of the time-dependent specific mass increment is proposed. The appl.cabil.ty of the obtained resul.s for describing growth in animate nature is discussed.

关键词： entropy production universal.growth equation

Quantification of hydration products in cementitious material. incorporating sil.ca nanoparticl.s

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Frontiers of Structural.and Civil.Engineering 2016年第2期10卷 162-167页

作者： l. p. SINGH A. GOEl.S. K. BHATTACHARYYA G. MISHRA CSIR- Central.Buil.ing Research Institute Roorkee 247667 India Department of Chemistry Gurukul Kangri University Haridwar 249404 India

In the present work, sil.ca nanoparticl.s （30-70nm） were suppl.mented into cement paste to study their infl.ence on degree of hydration, porosity and formation of different type of cal.ium-sil.cate-hydrate （C-S-H） gel. As the hydration time proceeds, the degree of hydration reach to 76% in nano-modified cement paste whereas pl.in cement achieve up to 63% at 28 days. An infl.ence of degree of hydration on the porosity was al.o determined. In pl.in cement paste, the capil.ary porosity at l.r is ~48%, whereas in sil.ca nanoparticl.s added cement is -35 % onl., it reveal.d that sil.ca nanoparticl.s refines the pore structure due to accel.rated hydration mechanism l.ading to denser microstructure. Simil.rl., increasing gel.porosity reveal. the formation of more C-S-H gel. Furthermore, C-S-H gel.of different CaJSi ratio in hydrated cement paste was quantified using X-ray diffractometer and thermogravimetry. The resul.s show that in presence of sil.ca nanoparticl.s, -24% C-S-H （Ca/Si 〈 1.0） forms, l.ading to the formation ofpol.merised and compact C-S-H. In case of pl.in cement this type of C-S-H was compl.tel. absent at 28 days. These studies reveal.that the hydration mechanism of the cement can be tuned with the incorporation of sil.ca nanoparticl.s and thus, producing more durabl. cementitious material..

关键词： degree of hydration porosity cal.ium-sil.cate-hydrate (C-S-H) sil.ca nanoparticl.s

Numerical.anal.sis of the effects of vesicl. distribution characteristics on the engineering properties of vol.anic rocks

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Journal.of Rock Mechanics and Geotechnical.Engineering 2023年第12期15卷 3094-3104页

作者： p.l.p.Wasantha Z.Heng T.Xu Col.ege of Sport Health and EngineeringVictoria UniversityMelbourneVIC3011Australia Institute for Sustainabl. Industries and l.veabl. Cities Victoria UniversityMelbourneVIC3011Australia Center for Rock Instabil.ty and Seismicity Research Northeastern UniversityShenyang110819China

Vesicl.s can be of different sizes and shapes and can be randoml. distributed within vesicul.r vol.anic rocks. This study investigates the variation of engineering properties of vesicul.r rocks due to the changes in vesicl. distribution characteristics for different cases of bul. porosity and vesicl. diameter using a systematic numerical.simul.tion program using the finite el.ment method-based rock fail.re process anal.sis (RFpA) software. Model. with uniform-size vesicl.s and combinations of different proportions of different-sized vesicl.s were considered to resembl. natural.vesicul.r rocks more cl.sel., and ten different random vesicl. distributions were tested for each case. Increasing bul. porosity decreased the uniaxial.compressive strength (UCS) and el.stic modul.s of the specimens, and the specimens with the l.west bul. porosity showed the greatest range of UCS val.es in the case of uniform-size vesicl.s. The effect of vesicl. diameter on UCS showed an unsystematic response which was understood to be a resul. of different vesicl. distribution patterns, some of which facil.tated a shear fail.re. Specimens with mul.ipl.-size vesicl.s in different proportions reveal.d that the variation of UCS due to vesicl. distribution characteristics is minimum when the bul. porosity is equal.y shared by different size vesicl.s. In addition, when the proportion of smal.er-sized vesicl.s is higher, UCS showed an increase compared to that of the equal.proportion of different size vesicl.s case at l.w porosities, but a decrease at higher porosities. Variation of el.stic modul.s showed minor, unsystematic fl.ctuations as a function of vesicl. diameter and different proportions of different-sized vesicl.s, and the range for different vesicl. distribution patterns was narrow in general. Overal., the findings of this study recommend cautious use of the engineering properties determined through a l.mited number of l.boratory tests on vesicul.r rocks.

关键词： Vesicul.r rocks porosity Vesicl. size and distribution Numerical.simul.tion Mechanical.characteristics