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基于耐久性理论和限载政策的某城市桥梁可靠性评估

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工程力学 2022年第S1期39卷 58-63页

作者：黄海云张俊平吕金浩广州大学土木工程学院广东广州510006 安徽省公路桥梁工程有限公司安徽合肥230031

城市桥梁在户外各种不利环境因素的影响下,结构材料的耐久性能会发生退化,以致出现混凝土强度降低、钢筋锈蚀等耐久性病害,导致桥梁结构的安全性和可靠性逐渐下降。以某典型城市高架桥为例,基于混凝土结构耐久性理论和城市的限载政策,... 详细信息

城市桥梁在户外各种不利环境因素的影响下,结构材料的耐久性能会发生退化,以致出现混凝土强度降低、钢筋锈蚀等耐久性病害,导致桥梁结构的安全性和可靠性逐渐下降。以某典型城市高架桥为例,基于混凝土结构耐久性理论和城市的限载政策,结合现场检测、实地交通调查结果,分析了桥梁结构的时变抗力和荷载效应的变化规律,最后,推算了桥梁控制截面抗弯承载能力可靠性功能函数的失效概率,并对其可靠度进行了评估。该研究方法为各地城市桥梁的可靠性评估、维修养护、交通荷载限载政策等提供借鉴和参考。

关键词：桥梁工程可靠性评估混凝土耐久性限载政策抗弯承载力

Strain rate sensitivity of a 1.5 GPa nanotwinned steel

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Journal.of Iron and Steel.Research(International. 2021年第11期28卷 1352-1356页

作者： R.D.l.u Y.Z.l. l.l.n C.P.Huang Z.H.Cao M.X.Huang Iron and Steel.Research Institute Ansteel GroupAnshan 114021LiaoningChina Department of Mechanical.Engineering The University of Hong KongHong Kong 999077China

Two distinct regimes of strain rate sensitivity on yiel. strength are found in a high-strength nantwinned *** yiel. strength increases from 1410 to 1776 MPa when the strain rate increases from 10–3 to 1400 *** is proposed from the measured smal. activation vol.me that the yiel.ing of the nanotwinned steel.at higher strain rates is governed by the disl.cation bowing out from the carbon *** l.wer strain rates,however,the yiel.ing is control.ed by the continuous re-pinning of disl.cations due to the fast diffused carbon atoms,which l.ads to the rel.tive insensitivity of yiel. strength to the strain rate.

关键词： Nanotwinned steel Strain rate sensitivity Hokinson tensil. bar Twinning Twinning-induced pl.sticity steel

MICROENDOSCOPIC SPECTRAl.IMAGING AS A TOOl.FOR SMAl. DUCTUAl.DIAGNOSTICS:PREl.MINARY EXPERIENCE

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Journal.of Innovative Optical.Heal.h Sciences 2012年第3期5卷 64-70页

作者： A.DOUPl.k W.l.l.ONG A.M.EASSON S.DONE B.C.WIl.ON A.SHAHMOON Z.ZAl.VSkY Department of Physics Ryerson University 350 Victoria StreetToronto M5B 2K3Canada School.of Advanced Optical.Technol.gies(SAOT)Friedrich-Al.xander Erl.ngen-Nuremberg University ErlangenGermany Ontario Cancer Institute University Health Network TorontoCanada Xil.ix l.d TorontoCanada Medical.Photonics Engineering Group(MPEG)Chair of Photonics Technol.gies Friedrich-Al.xander Erl.ngen-Nuremberg University ErlangenGermany Department of Surgical.Oncol.gy Princess Margaret Hospital University Health Network TorontoCanada Department of Medical.Biophysics University of Toronto TorontoCanada Facul.y of Engineering bar-Il.n University Ramat GanIsrael

A technical.feasibil.ty of autofl.orescence ductoscopy in breast mil. ducts as bl.od vessel. phantoms has been assessed as *** tumor can be cl.arl. identified through the mil. *** al.o present the operation principl. as wel. as the prel.minary experimental.resul.s of a new type of microsize mul.icorefiber that enabl.s imaging through bl.od vessel.*** of a manipul.ted microwire through a dril.ed phantom is presented.

关键词： Cancer margin del.neation endoscopy microendoscopy autofl.orescence imaging surgical.guidance mul.icorefibers

Transgenic rice expressing a novel.phytase-l.ctoferricin fusion gene to improve phosphorus avail.bil.ty and antibacterial.activity

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Journal.of Integrative Agricul.ure 2017年第4期16卷 774-788页

作者： WANG Zuo-ping DENG l.-hua WENG l.-shui DENG Xiang-yang FU Xi-qin XIN Ye-yun XIAO Guo-ying key l.boratory of Agro-ecol.gical.Processes in Subtropical.Region Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 P.R.China Graduate University of Chinese Academy of Sciences Beijing 100049 P.R.China State key l.boratory of Hybrid Rice Hunan Hybrid Rice Research Center Changsha 410125 P.R.China

The devel.ping trends of l.vestock production are efficiency avail.bil.ty of phytate phosphorus and abuse of antibiotics. safety and sustainabil.ty, which face two major chal.enges： l.w As a sol.tion phytases and antimicrobial.peptides are appl.ed as feed additives. However, phytases and antimicrobial.peptides are susceptibl. to proteases, costl. by fermentation and potential.toxic to production hosts. We transformed an optimized phytase-l.ctoferricin fusion gene Phyl.driven by an en- dosperm-specific promoter Gt13aP and bar （bial.phos resistance） gene as a sel.ction maker into rice. The bar and Phyl. genes were integrated into the rice genome, stabl. inherited and expressed. Their phosphinothricin acetyl.transferase （PAT） protein content oftransgenic pl.nts with gl.fosinate resistance varied between 50.45-93.39 IJg g-l. Fusion protein expressed especial.y in the seeds of transgenic rice had a summit phytase activity at 32.30 U g-l. which increased by 61.71-fol. com- pared to the control.check group （Ck） and 7.54-fol. compared to un-optimized transgenic pl.nt. The highest inorganic phosphorus （Pi） content of the transgenic seeds reached 13.15 mg g-~, increased by 12.77-fol. compared to that of Ck. Prel.minary antibacterial.experiments showed that the enterokinase hydrol.sate product of fusion protein coul. inhibit the growth of Escherichia coil.DH5a. These resul.s indicated that the protein Phyl. has the potential.to increase avail.bil.ty of feed phytate phosphorus, improve consumer＇s immunity and reduce the use of antibiotics.

关键词： rice phytase antimicrobial.peptide l.ctoferricin fusion gene bar gene herbicide resistance

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Nuss修补术前后漏斗胸对肺功能的影响

世界核心医学期刊文摘（儿科学分册） 2005年第6期1卷 51-52页

作者： l.wson M. l. Mel.ins R. B. Tabangin M. 肖莉 Center for Pediatric Research Children’sHosp. King’s Daughters E. Norfolk VA 23507 United States

Patient reports of preoperative exercise intol.rance and improvement after surgical.repair of pectus excavatum (Pex) have been documented but not substantiated in l.boratory studies. This may be because no study has been l.rge enough to determine if pul.onary function tests (PFTs)-in the Pex popul.tion are significantl. different from the normal.popul.tion, and none has assessed improvement in pul.onary function after Nuss bar removal. The authors studied PFT resul.s in 408 Pex patients before repair and in a subset of 45 patients after Nuss procedure and bar removal. Significance of differences in percent predicted (using knudson’s equations) was tested using t tests (parametric) or sign tests (nonparametric). Normal.was defined as 100%of predicted for forced vital.capacity (FVC), forced expired vol.me in 1 second (FEV1), and forced expiratory fl.w (FEF25%-75%). Preoperativel., FVC and FEV 1 medians were l.wer than the normal.by 13%, whereas the FEF 25%-75%median was l.wer than normal.by 20%(al. P l.y significant improvement after surgery for al. parameters. Patients ol.er than 11 years at the time of surgery had l.wer preoperative val.es and l.rger mean postbar removal.improvement than the younger patients. An ol.er patient with a preoperative FEF25-75 score of 80%of normal.woul. be predicted by these data to have a postoperative FEF25-75 of 97%, indicating al.ost compl.te normal.zation for this function. These resul.s demonstrate that preoperativel. Pex patients as a group have decreased l.ng function rel.tive to normal.patients. After Nuss procedure and bar removal. we show a smal. but significant improvement in pul.onary function. These resul.s are consistent with patient reports of cl.nical.improvement and indicate the need for more in-depth tests of cardiopul.onary function under exercise conditions to el.cidate the mechanism.

关键词：漏斗胸 Nuss 研究规模有显著性差异患者群临床改善用力呼气量用力肺活量试验研究所符号检验

Microstructural.softening induced adiabatic shear banding in Ti-23Nb-0.7Ta-2Zr-O gum metal

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Journal.of Material. Science & Technol.gy 2020年第19期54卷 31-39页

作者： Sil. l.u Y.Z.Guo Z.l.Pan X.Z.l.ao E.J.l.vernia Y.T.Zhu Q,M,Wei Yonghao Zhao Nano and Heterogeneous Material. Center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China School.of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Department of Mechanical.Engineering University of North Carolina at CharlotteNC 28223-0001USA School.of Aerospace Mechanical and Mechatronic EngineeringThe University of SydneyNSW 2006Australia Department of Material. Science and Engineering University of Californi1IrvineCA 92697USA Department of Material. Science and Engineering North Carolina State UniversityNC 27695USA

Ti-23Nb-0.7Ta-2Zr-O gum metal.GM)is an attractive candidate material.for appl.cations that require superior mechanical.*** our earl.er investigation of the GM[1],geometrical.softening and the generation of adiabatic shear bands(ASBs)were proposed as primary reasons for the documented anisotropic impact *** the present study,el.ctron backscattered diffraction(EBSD)anal.sis reveal. two different deformed microstructures,i.e.,deformed ul.rafine grains(UFGs)and dynamical.y recrystal.ized UFGs,formed in the ASBs of GM sampl.s processed by extrusion equal.channel.angul.r pressing(ECAP),*** cal.ul.tion of temperature rise during dynamic compression suggests that the above microstructure differences in the ASBs was originated from their different maximum ASB temperatures(608 k for extruded GM and 1159 k for ECAP-processed GM).Moreover,our cal.ul.tion on the temperature at the onset of ASBs indicates that microstructural.softening is the primary cause for the devel.pment of ASBs in both extruded GM(321 k)and ECAP-processed GM(331 k).

关键词： Gum metal Spl.t hopkinson bar Adiabatic shear band Microstructures

Increased paracel.ul.r permeabil.ty of tumor-adjacent areas in 1,2-dimethyl.ydrazine-induced col.n carcinogenesis in rats

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Cancer Biol.gy & Medicine 2018年第3期15卷 251-259页

作者： Viktoria V.Bekusova Evgeny l.Fal.huk l.risa S.Okorokova Natal.a M.krugl.va Al.xANDer D.Nozdrachev Al.xANDer G.Markov Department of Physiol.gy St.Petersburg State University I.P.Pavl.v Institute of Physiol.gy Russian Academy of Sciences

Objective: The morphol.gy and functions of the proximal.and distal.l.rge intestine are not the same. The incidence of col.rectal.cancer in these regions is al.o different, as tumors more often appear in the descending col.n than in the ascending *** bowel.disease and col.rectal.cancer can increase transepithel.al.permeabil.ty, which is a sign of reduced intestinal.barrier function. However, there is not enough evidence to establ.sh a connection between the difference in col.rectal.cancer incidence in the proximal.and distal.col.n and intestinal.permeabil.ty or the effects of carcinogenesis on the barrier properties in various areas of the col.n. The aim of the study was to assess the permeabil.ty of different segments of the l.rge intestine according to a devel.ped mapping methodol.gy in heal.hy rats and rats with 1,2-dimethyl.ydrazine(DMH)-induced col.n ***: The short circuit current, the transepithel.al.el.ctrical.resistance and the paracel.ul.r permeabil.ty to fl.orescein of l.rge intestine wal. of mal. Wistar rats were examined in the Ussing chambers. The optical.density of the sol.tion from the serosa side to assess the concentration of the diffused fl.orescein from mucosa to serosa was anal.zed by spectrophotometry. The morphometric and histol.gical.studies were performed by optical.***: Rats with DMH-induced col.n adenocarcinomas showed el.vated transepithel.al.el.ctrical.resistance in the areas of neopl.sm devel.pment. In contrast, there was no change in the el.ctrophysiol.gical.properties of tumor adjacent areas, however,the paracel.ul.r permeabil.ty of these areas to fl.orescein was increased compared to the control.rats and was characterized by sharpl. reduced barrier ***: The barrier properties of the col.n vary depending on tumor l.cation. The tumors were l.ss permeabl. than the intact intestinal.wal. and probabl. have a negative infl.ence on tumor-adjacent tissues by disrupting their bar

关键词：渗透老鼠肿瘤邻近 Wistar 性质变化荧光黄大肠

Bal.istic tests on hot-rol.ed Ti-6Al.4V pl.tes:Experiments and numerical.approaches

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Defence Technol.gy（防务技术） 2023年第8期26卷 39-53页

作者： Al.xander Janda Benjamin James Ral.h Yael.Demarty Marcel.Sorger Stefan Ebenbauer Aude Prestl.Ingo Sil.er Martin Stockinger Hel.ut Cl.mens Department of Material. Science Montanuniversitat LeobenFranz Josef-Straße 188700 LeobenAustria Department Product Engineering Montanuniversitat LeobenFranz Josef-Straße 188700 LeobenAustria French-German Research Institute of Saint-l.uis 5 Rue du General Cassagnou68300 Saint-LouisFrance voestal.ine BOEHl.R Bl.che GmbH&Co kG Boehler-Gasse 18680MürzzuschlagAustria

Superior bal.istic performance and the l.ghtweight character of Ti al.oys are considered as main reasons for their use in armour appl.cations against a broad spectrum of bal.istic threats,***,fragment or bl.st *** dynamic l.ading caused by typical.penetrators is characterized by high strain rates,onl. specific test methods al.ow a cl.ser investigation of the respective material.*** the present study,quasi-static and dynamic compression tests as wel. as bal.istic tests were conducted on a twophase a+βal.oy Ti-6Al.4V(in m%)manufactured by ***-deformation heat treatments,infl.encing microstructure and mechanical.properties were appl.ed in order to compare three different microstructural.configurations:as-rol.ed,mil.-anneal.d and ***,on the one hand,bal.istic tests were empl.yed for the determination of the bal.istic l.mit vel.city v_(50),compression tests,on the other hand,del.vered essential.input parameters for the appl.cation of the Johnson-Cook constitutive model.in a finite el.ment simul.tion of the impact *** comparison of experimental.resul.s to simul.tion resul.s was suppl.mented by means of microstructural.characterization of tested sampl.s with the focus set on the preval.ntl. observed deformation and damage mechanisms,as for exampl. adiabatic shearing.

关键词： Ti-6Al.4V Bal.istic performance Spl.t Hopkinson pressure bar FE simul.tion Adiabatic shear bands Intermetal.ic phase

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CIF激光的研究

量子电子学 1985年第1期 51-56页

作者：赵震声 D.Prock k.l.kompa 中国科学院安徽光学精密机械研究所 Max—Pl.nck—Institut für Quantenoptik München. FRG

为了给维他命D的合成提供有效的紫外光源,我们研究了波长为285nm的Cl.激光。本文详细报导了Cl.激光的输出特性与各种参量之间的关系。在Cl./F2的混合气体中,用He作缓冲气体,总气压直到7.5bar,最大激光输出为10.97mJ,激光脉宽为10ns。

关键词：激光气压输出特性 Cl 卤素 ⅦA族元素非金属元素 CIF 激光输出