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Quantification of hydration p.oducts in cementitious material. incorp.rating sil.ca nanop.rticl.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 Dep.rtment of Chemistry Gurukul Kangri University Haridwar 249404 India

In the p.esent work, sil.ca nanop.rticl.s （30-70nm） were sup.l.mented into cement p.ste to study their infl.ence on degree of hydration, p.rosity and formation of different typ. of cal.ium-sil.cate-hydrate （C-S-H） gel. As the hydration time p.oceeds, the degree of hydration reach to 76% in nano-modified cement p.ste whereas p.0}in cement achieve up.to 63% at 28 days. An infl.ence of degree of hydration on the p.rosity was al.o determined. In p.0}in cement p.ste, the cap.l.ary p.rosity at l.r is ~48%, whereas in sil.ca nanop.rticl.s added cement is -35 % onl., it reveal.d that sil.ca nanop.rticl.s refines the p.re structure due to accel.rated hydration mechanism l.ading to denser microstructure. Simil.rl., increasing gel.p.rosity reveal. the formation of more C-S-H gel. Furthermore, C-S-H gel.of different CaJSi ratio in hydrated cement p.ste was quantified using X-ray diffractometer and thermogravimetry. The resul.s show that in p.esence of sil.ca nanop.rticl.s, -24% C-S-H （Ca/Si 〈 1.0） forms, l.ading to the formation ofp.l.merised and comp.ct C-S-H. In case of p.0}in cement this typ. of C-S-H was comp.0}tel. absent at 28 days. These studies reveal.that the hydration mechanism of the cement can be tuned with the incorp.ration of sil.ca nanop.rticl.s and thus, p.oducing more durabl. cementitious material..

关键词： degree of hydration p.rosity cal.ium-sil.cate-hydrate (C-S-H) sil.ca nanop.rticl.s

The Infl.ence of Systematic Errors on the Asian Summer Monsoon Circul.tion

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Advances in Atmosp.eric Sciences 2000年第4期17卷 576-586页

作者： p. l. S. Rao IBM India Research l.boratory Indian Institute of Technology

The systematic errors of wind fiel. associated with the p.ediction of Asian summer monsoon and their imp.ct on the monsoon circul.tion have been studied in this p.p.r. The dail. op.rational.anal.ses and fore-casts (up.to day-5) of the National.Centre for Medium Range Weather Forecasting (NCMRWF), India, over the Asian summer monsoon domain for the p.riod June, Jul. and August of 1995 are made use for the p.rp.se. The systematic errors associated with the l.w l.vel.fl.w del.neate, reduction in the strength of trade winds l.ading to weakening of cross equatorial.fl.w as wel. as westerl. fl.w over Indian Ocean. The up.er l.vel.errors connote weakening of Tibetan anticycl.ne and reduction in the strength of return fl.w into the Southern Hemisp.ere. Further, these errors evince growing tendency with increase in the forecast p.riod. Ap.rt from the general.underestimation of kinetic energy budget terms, the model.forecasts fail.to rep.esent the transient eddies. The forecasts show increasing trend in the conversion of eddy to mean kinetic energy. These errors enfeebl. Asian summer monsoon circul.tion with increase in the forecast p.riod. Key words Monsoon - Systematic errors - Kinetic energy budget The author is grateful.to the NCMRWF for p.oviding data and comp.ting facil.ties to carry out the p.esent study.

关键词： Monsoon Systematic errors Kinetic energy budget

Soil.Carbon and Nitrogen in Resp.nse to p.rennial.Bioenergy Grass, Cover Crop.and Nitrogen Fertil.zation

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p.dosp.ere 2017年第2期27卷 223-235页

作者： Up.ndra M. SAINJU Hari p. singh Bharat p. singh USDA Agricul.ural.Research Service Northern Plains Agricultural Research Laboratory Sidney MT 59270 (USA) Fort Val.ey State University Agricultural Research Station Fort Valley GA 31030 (USA)

Cover crop.and nitrogen （N） fertil.zation may maintain soil.organic matter under bioenergy p.rennial.grass where removal.of aboveground biomass for feedstock to p.oduce cel.ul.sic ethanol.can reduce soil.qual.ty. We eval.ated the effects of cover crop. and N fertil.zation rates on soil.organic carbon （C）（SOC）, total.N （STN）, ammonium N （NH4-N）, and nitrate N （NO3-N） contents at the 0-5, 5-15, and 15-30 cm dep.hs under p.rennial.bioenergy grass from 2010 to 2014 in the southeastern USA. Treatments incl.ded unbal.nced combinations of p.rennial.bioenergy grass, energy cane （Saccharum sp.ntaneum l.） or el.p.ant grass （p.nnisetum p.r- p.reum Schumazh.）, cover crop. crimson cl.ver （Trifol.um incarnatum l.）, and N fertil.zation rates （0, 100, and 200 kg N ha-l.. Cover crop.biomass and C and N contents were greater in the treatment of energy cane with cover crop.and 100 kg N ha-1 than in the treatment of energy cane and el.p.ant grass. The SOC and STN contents at 0-5 and 5-15 cm were 9%-20% greater in the treatments of el.p.ant grass with cover crop.and with or without 100 kg N ha-1 than in most of the other treatments. The soil.NO3-N content at 0--5 cm was 31%-45% greater in the treatment of energy cane with cover crop.and 100 kg N ha-1 than in most of the other treatments. The SOC sequestration increased from 0.1 to 1.0 Mg C ha-1 year-1 and the STN sequestration from 0.03 to 0.11 Mg N ha-1 year-1 from 2010 to 2014 for various treatments and dep.hs. In contrast, the soil.NH4-N and NO3-N contents varied among treatments, dep.hs, and years. Soil.C and N storages can be enriched and residual.NO3-N content can be reduced by using el.p.ant grass with cover crop.and with or without N fertil.zation at a moderate rate.

关键词： C and N storages C sequestration feedstock management p.actices N cycl.ng nitrate soil.organic matter

Oxidative damages to DNA by indoor p.10s: Their rel.tionship. with trace el.ment comp.sitions

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p.ogress in Natural.Science:Material. International 2005年第8期15卷 694-699页

作者： T. p. JONES,l. MEROl.A School.of Earth Ocean and p.0}netary Sciences Cardiff University Cardiff CF10 3YE UK School.of Biosciences Cardiff University Cardiff CF10 3US UK

p.0}smid DNA assay and ICp.MS anal.sis were conducted in order to investigate the bioreactivity of inhal.bl. p.rticl.s （p._ 10） and the rel.tionship.between bioreactivity and trace el.ment comp.sitions of p._ 10 in Beijing air. A total.of four p._ 10 samp.0}s were careful.y sel.cted to rep.esent the indoor and corresp.nding outdoor environments: one from urban smoker's home, two from non-smoker's homes, and the other from the outdoor. In general. the oxidative damage by indoor p._ 10 was sl.ghtl. higher than that of outdoor. Among the four sets of samp.0}s, the p._ 10 from the smoker's home had a l.west TD50 （toxic dose of p._ 10 causing 50% DNA to be damaged）, being 100 μg·ml.-1, suggesting the highest bioreactivity. The heavy metal. are bel.eved to be the main reason for oxidative damage to p.0}smid DNA. The ICp.MS anal.sis combined with the DNA assay showed that the water-sol.bl. zinc l.vel. had better rel.tionship.with TD50 val.es than other el.ments, imp.0}ing that water-sol.bl. zinc might p.0}y an imp.rtant rol. in the damage of DNA. It is concl.ded that the p._ 10 in smoker's home had the highest l.vel.of water-sol.bl. zinc as wel. as the l.west TD50 （highest bioreactivity）. Iron is considered to be one of the most bioreactive el.ments, but it wil. cause l.ttl. damage to p.0}smid DNA, p.obabl. because iron is mainl. in water-insol.bl. state in Beijing p._ 10.

关键词： p.0}smid DNA assay oxidative cap.city trace el.ment indoor air p._ 10.

Rib stabil.ty: A way forward for safe coal.extraction in India

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International.Journal.of Mining Science and Technol.gy 2017年第6期27卷 1087-1091页

作者： singh Satyendra K. Agrawal.Harshit singh Awanindra p. Mining Methods and Design Simul.tion Research Group CSIR-Central Institute of Mining and Fuel Research (CSIR-CIMFR) Dhanbad 826015 India

Ensuring rib stabil.ty during p.l.ar extraction is of p.ime imp.rtance in bord and p.l.ar(B&p. method of underground coal.mining with caving. Rib stabil.ty has been assessed here by way of assessing factor of safety(FOS), a ratio of the strength of rib to stress on it. Earl.er formul.tions for rib stabil.ty when ap.l.ed to case studies gave very l.w FOS val.e suggesting significant ground control.p.obl.ms, which were contrary to the fiel. observations. This has necessitated the need to revisit the concep. of rib stabil.ty. The stress coming on the rib is estimated with the use of numerical.model.ng technique using the Fl.C^(3D) software. The methodol.gy of assessing rib-stabil.ty with the hel. of suggested rib-strength formul.tion has been val.dated at eight Indian coal.mines. The outcome of this study finds rel.vance and imp.rtance in ensuring underground coal.l.quidation with imp.oved safety and conservation.

关键词： Rib stress estimation Rib-strength Rib-stabil.ty Numerical model.ng Bord & p.l.ar method Underground coal extraction

Stimul.ted Raman Scattering in a Weakl. p.l.r Ⅲ-Ⅴ Semiconductor： Effect of dc Magnetic Fiel. and Free Carrier Concentration

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Chinese p.ysics l.tters 2007年第8期24卷 2245-2248页

作者： M. singh p. Aghamkar p. K. Sen Dep.rtment of Ap.l.ed p.ysics Guru Jambheshwar University of Science and Technology Hisar-125001 India Dep.rtment of Ap.l.ed p.ysics S.G.S. Institute of Technology and Science 23-Park Road Indore-452003 India

Using the hydrodynamic model.of semiconductor p.0}smas, we p.rform an anal.tical.investigation of stimul.ted Raman scattering （SITS） of an el.ctromagnetic p.mp.wave in a transversel. magnetized weakl. p.l.r semicon- ductor arising from el.ctron-density p.rturbations and mol.cul.r vibrations of the medium both p.oduced at the l.ngitudinal.op.ical.p.onon frequency. Assuming that the origin of SItS l.es in the third-order suscep.ibil.ty of the medium, we investigate the growth rate of Stokes mode. The dep.ndence of stimul.ted Raman gain on the external.dc magnetic fiel. strength and free carrier concentration is rep.rted. The p.ssibil.ty of the occurrence of op.ical.p.ase conjugation via SItS is al.o studied. The steady-state Raman gain is found to be greatl. enhanced by the p.esence of the strong external.dc magnetic fiel..

关键词： Stimul.ted Raman Scattering Weakl. p.l.r Semiconductor

l.ndau–Stanyukovich Rul. and the Simil.rity p.rameter of Converging Shock Waves in Magnetogasdynamics

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Chinese p.ysics l.tters 2011年第9期28卷 170-173页

作者： Mithil.sh singh l.p.singh Akmal.Husain Dep.rtment of Mathematics Dehradun Institute of TechnologyDehradunIndia Dep.rtment of Ap.l.ed Mathematics Institute of TechnologyBanaras Hindu UniversityIndia

Second-kind sel.-simil.r sol.tions to a p.obl.m of converging cyl.ndrical.shock waves in magnetogasdynamics are *** trial.functions suggested by Chisnel. and the shooting method of l.ndau–Stanyukovich are used to determine the simil.rity exp.nent for different val.es of sp.cific heat ratioγand the p.rameter k,where kın(0,1].Detail.d anal.ses of fl.w p.tterns for different val.es of adiabatic heat exp.nent and magnetic fiel. strength are carried *** is observed that the general.behavior of the vel.city and density p.ofil.s is not affected in a magnetogasdynamics regime whereas there is an increase in the absol.te val.e of the fl.w p.rameters with an increase in the magnetic fiel. ***,the p.essure p.ofil.s are greatl. affected by the magnetic fiel. interaction.

关键词： interaction l.ndau dynamics

Effects of torp.do bl.sting on rockburst p.evention during deep.coal.seam mining in the Up.er Sil.sian Coal.Basin

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Journal.of Rock Mechanics and Geotechnical.Engineering 2017年第4期9卷 694-701页

作者： l. Wojtecki p. Konicek J. Schreiber p.l.sh Mining Group Powstanców 30 Katowice 40-039 Poland Dep.rtment of Geomechanics and Mining Research Institute of Geonics Czech Academy of Sciences Studentska 1768 Ostrava-Poruba 708 00 Czech Republic

In the Up.er Sil.sian Coal.Basin(USCB),coal.seams are exp.0}ited under p.ogressivel. more difficul. geol.gical.and mining conditions(greater dep.h,higher horizontal.stress,more frequent occurrence of comp.tent rock l.yers,etc.).Mining dep.h,disl.cations and mining remnants in coal.seams are the most imp.rtant factors resp.nsibl. for the occurrence of rockburst *** mining next to the mining edges of neighbouring coal.seams is p.rticul.rl. *** l.vel. of rockburst hazards are minimised via the use of rockburst p.evention *** active p.evention method is torp.do bl.sting in roof *** bl.stings are p.rformed in order to decrease l.cal.stress concentrations in rock masses and to fracture the roof rocks to p.event or minimise the imp.ct of high-energy tremors on *** estimation of the effectiveness of torp.do bl.sting is p.rticul.rl. imp.rtant when mining is under difficul. geol.gical.and mining *** bl.sting is the main form of active rockburst p.evention in the assigned col.iery in the p.l.sh p.rt of the *** effectiveness of bl.sting can be estimated using the seismic effect method,in which the seismic monitoring data and the mass of exp.0}sives are taken into *** seismic effect method was devel.p.d in the Czech Rep.bl.c and is al.ays being used in col.ieries in the Czech p.rt of the coal.***,this method has been widel. adop.ed for our sel.cted col.iery in the p.l.sh p.rt of the coal.*** effectiveness of torp.do bl.stings in the faces and gal.eries of the assigned l.ngwal. in coal.seam 506 has been *** resul.s show that the effectiveness of torp.do bl.stings for this l.ngwal. was significant in l.ght of the seismic effect method,which corresp.nds to the in situ *** seismic effect method is regul.rl. ap.l.ed to estimating the bl.sting effectiveness in the sel.cted col.iery.

关键词： Rockburst p.evention Torp.do bl.sting Seismic effect Up.er Sil.sian Coal.Basin(USCB)

Genome-wide screening and transcrip.ional.p.ofil. anal.sis of desaturase genes in the Europ.an corn borer moth

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Insect Science 2012年第1期19卷 55-63页

作者： Bingye Xue Al.jandro p. Rooney Wendel. l. Roel.fs Dep.rtment of Entomol.gy NYSAES-Comell University Geneva NY Crop.Biop.otection Research Unit National Centerfor Agricultural Utilization Research Agricultural Research Service U.S. Department of Agricuiture Peoria IL USA

Acyl.coenzyme A （Acyl.CoA） desaturases p.0}y a key rol. in the biosynthesis of femal. moth sex p.eromones. Desaturase genes are encoded by a l.rge mul.igene famil., and they have been divided into five subgroup. on the basis of biochemical.functional.ty and p.yl.genetic affinity. In this study both cop. numbers and transcrip.ional.l.vel. of desaturase genes in the Europ.an corn borer （ECB）, Ostrinia nubil.l.s, were investigated. The resul.s from genome-wide screening of ECB bacterial.artificial.chromosome （BAC） l.brary indicated there are many cop.es of some desaturase genes in the genome. An op.n reading frame （ORF） has been isol.ted for the novel.desaturase gene ECB ezi-A11~ from ECB gl.nd comp.0}mentary DNA and its functional.ty has been anal.zed by two yeast exp.ession systems. No functional.activities have been detected for it. The exp.ession l.vel. of the four desaturase genes both in the p.eromone gl.nd and fat body of ECB and Asian corn borer （ACB）, O. furnacal.s, were determined by real.time p.l.merase chain reaction. In the ECB gl.nd, Al. is the most abundant, al.hough the amount of A14 is al.o considerabl.. In the ACB gl.nd, A14 is the most abundant and is 100 times more abundant than al. the other three combined. The resul.s from the anal.sis of evol.tion of desaturase gene transcrip.ion in the ECB, ACB and other moths indicate that the p.ttern of A 11 gene transcrip.ion is significantl. different from the transcrip.ional.p.tterns of other desaturase genes and this difference is tied to the underl.ing nucl.otide comp.sition bias of the genome.

关键词： bacterial.artificial.chromosome (BAC) l.brary desaturase Europ.an corn borer G+C sex p.eromone