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Ion motion effects on the generation of short-cycle relativistic laser pulses during radiation pressure acceleration

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High Power Laser Science and Engineering 2014年第2期2卷 1-7页

作者： W.P.Wang X.M.Zhang X.f.Wang X.Y.Zhao J.C.Xu Y.H.Yu L.Q.Yi Y.Shi L.G.Zhang T.J.Xu C.Liu Z.K.Pei B.f.Shen State Key Laboratory of High field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

The effects of ion motion on the generation of short-cycle relativistic laser pulses during radiation pressure acceleration are investigated by analytical modeling and particle-in-cell simulations. Studies show that the rear part of the transmitted pulse modulated by ion motion is sharper compared with the case of the electron shutter only. In this study, the ions further modulate the short-cycle pulses transmitted. A 3.9 fs laser pulse with an intensity of 1.33×1021W cm-2is generated by properly controlling the motions of the electron and ion in the simulations. The short-cycle laser pulse source proposed can be applied in the generation of single attosecond pulses and electron acceleration in a small bubble regime.

关键词： radiation pressure acceleration short-cycle pulses particle-in-cell simulations.

Retention of eucalyptus harvest residues reduces soil compaction caused by deep subsoiling

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Journal of forestry Research 2022年第2期33卷 643-651页

作者： Raphael Oliveira de Melo AymbiréAngeletti da fonseca Nairam félix de Barros Raphael Bragança Alves fernandes Rafael da Silva Teixeira Iago Nery Melo Ricardo Previdente Martins Soil Science Department Universidade Federal de ViçosaViçosaMinas GeraisBrazil BRACELL Company AlagoinhasBahiaBrazil

Eucalyptus harvesting,forwarding and soil tillage operations are among the main causes for compaction of forest soils,with potential impacts on *** concern is especially important in areas with soils that are naturally compacted(fragipans and duripans).In these soils,tillage operations include the use of subsoilers that can reach depths of more than one meter and require heavy tractors that exert high pressure on the *** of the ways to try to minimize the effect of this compaction is by retaining harvest *** objective of this study was to evaluate the impacts of eucalyptus harvesting on soil physical attributes,as well as to determine the potential of different types of residue management to reduce compaction from the soil tillage *** experiments were conducted in the same area with a Yellow *** the first experiment,compaction caused by mechanized harvesting with harvester+forwarder was *** the second experiment,different managements of harvest residues were examined as potential modifiers of soil compaction during tillage for new *** this,three managements systems were tested:(1)retention of all harvest residues and litter from the previous rotation(HR+L),(2)retention of litter from the previous rotation(L),and(3)removal of harvest residues and litter from the previous rotation(WR).Before and after harvest,sampling was carried out in the planting rows and inter-rows,and after tillage,samples were collected in the traffic line of the subsoiler-tractor *** both experiments,undisturbed soil samples were collected from the center of the 0-10,10-20,20-40,40-60,and 60-100 cm layers to determine soil density and total *** each period and site of evaluation,mechanical resistance to penetration up to the 60-cm depth was also *** harvesting operation increased soil density at 0-10 and 60-100 cm depths only in the *** of harvest residues and litter(HR+L)after harvesting avoi

关键词： Soil penetration resistance Harvester+forwarder Soil tillage Soil density Cohesive soils

Micro-Structured fiber Interferometer as Sensitive Temperature Sensor

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Photonic Sensors 2013年第3期3卷 208-213页

作者： f. C. fAVERO M. BECKER, R. SPITTEL M. ROTHHARDT J. KOBELKE H. BARTELT Institute of Photonic Technology (IPHT) Albert-Einstein-Strafle-9 07745 Jena Germany

We report on a fast and sensitive temperature sensor using a micro-structured or photonic crystal fiber interferometer with a high germanium doped fiber core. The wavelength sensitivity for temperature variation was as high as △λ/△T= 78 pm/℃ up to 500℃, which was 6 times more sensitive than the fiber Bragg grating temperature sensitivity of △λ/△TT= 13pm/℃ at 1550nm. The sensor device was investigated conceming the sensitivity characteristics and response time.

关键词： Micro-structured optical fiber fiber interferometer fiber temperature sensor

Effects of Autoclaving and Mercuric Chloride Sterilization on PAHs Dissipation in a Two-Liquid-Phase Soil Slurry

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Pedosphere 2011年第1期21卷 56-64页

作者： WANG Cong-Ying WANG fang WANG Tao YANG Xing-Lun BIAN Yong-Rong f. O. KENGARA LI Zeng-Bo JIANG Xin State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) School of Environmental Science and Resources Shanxi University Taiyuan 030006 (China) Department of Chemistry Maseno University Private Bag Maseno (Kenya) Institute of Chemical and Biological Technology Taiyuan University of Science and Technology Taiyuan 030021 (China)

A two-liquid-phase （TLP） soil slurry system was employed to quantify the efficiencies of autoclaving and mercuric chloride sterilization in the dissipation of polycyclic aromatic hydrocaxbons （PAHs）. The fates of 11 PAHs （naphthalene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo（a）anthracene, benzo（a）pyrene, benzo（b）fluoranthene, benzo（k）fluoranthene, dibenzo（a, h）anthracene） were recorded over 113 days of incubation. No microorganisms were detected in the HgC12-sterilized soil slurries during the whole incubation period, indicating very effective sterilization. However, about 2% 36% losses of PAHs were observed in the HgCl2- sterilized slurry. In contrast to the HgCl2-sterilized soil slurry, some microorganisms survived in the autoclaved soil slurries. Moreover, significant biodegradiation of 6 PAHs （naphthalene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene） was observed in the autoclaved soil slurries. This indicated that biodegradation results of PAHs in the soil slurries, calculated on basis of the autoclaved control, would be underestimated. It could be concluded that the sterilization efficiency and effectiveness of HgCl2 on soil slurry was much higher than those of autoclaving at 121 ℃ for 45 rain.

关键词： adsorption aqueous solubility biodegradation microorganisms octanol-water partition coefficient

Effects of the substitution of cow’s milk with soymilk on the micronutrients,microbial,and sensory qualities of yoghurt

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food Production, Processing and Nutrition 2022年第1期4卷 162-171页

作者： Dupe T.Otolowo Omolola M.Omosebi Kudirat T.Araoye Temiloluwa E.Ernest Oluwatooyin f.Osundahunsi Department of food Science and Technology Mountain Top UniversityPrayer CityNigeria Department of food Science and Technology Wesley University OndoOndoNigeria Department of food Science and Technology Federal University of Oye-EkitiOye-EkitiNigeria Department of food Science and Technology Federal University of TechnologyAkureNigeria

The consumption of imported dairy products is high especially in developing countries including Nigeria where little or no milk is produced locally which makes the products expensive,out of reach to common consumers and also inconvenient for lactose intolerance and ***,as plant-based milk was substituted for cow’s milk in parts and in whole for the production of yoghurt and the effect of substitution was evaluated on the minerals,vitamins,microbial,and sensory properties of the products using the established *** differences(ptents’range of 0.14–28.50 mg/100 g and vitamin contents(ranged 0.02–0.43 mg/100 g)that were of comparable range of values with the yoghurt made with 100%cow’s milk(0.21–29.60 mg/100 g minerals and 0.05–0.58 mg/100 g vitamins).Generally,no significant difference(pf the sensory attributes evaluated(range 8.00–8.01)in the entire samples(except in the 100%soymilk yoghurt).The microbial analysis proved the safety of the entire products for *** showed the positive effect of substituting soymilk for cow’s milk at all the levels used,thus,the lactose intolerance and vegans can find alternative to dairy yoghurt in the 100%soymilk substitution and enjoy the functional health benefits of ***,the total dependence on importation of dairy milk and cost of production of composited milk yoghurt could be reduced to improve the nation’s economy and make the product economically accessible to common man.

关键词： Cow’s milk Soymilk Yoghurt Mineral and vitamin contents Microbial quality Sensory acceptability

Influence of Process Variables on the Structure of Mechanically Alloyed Ti_3Al-base Intermetallics

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Rare Metals 1993年第4期12卷 241-249页

作者： Chen Guohao Suryanarayana C.and froes f.H.(Sam)Institute for Materials and Advanced Processes,University of Idaho,Moscow,ID 83843-4195,U.S.A. University of Idaho 美国

During mechanical alloying variables such as the type of mill,milling intensity,milling time,milling at- mosphere and ball-to-powder weight ratio(BPR)affect the morphology and constitution of the product. The effect of milling time,milling atmosphere and BPR on the nature of the product formed in mechanical- ly alloyed pure Ti and blended elemental binary Ti-Al,and ternary Ti-AI-Nb alloy powders was described. Mechanical alloying of pure titanium results,after long milling times,in the formation of an fcc *** the binary alloy,a solid solution of aluminum in titanium,an amorphous phase,and a fcc phase form with increasing milling *** fcc phase,which is probably a result of TiN formation,occurs more rapidly in air or nitrogen than in an inert *** of the B2 phase in the ternary alloys depends both on alloy composition and the milling atmosphere,with 100％ formation in all atmospheres in Ti-25Al-25Nb but not in Ti-24Al-11Nb,and an inert atmosphere favoring *** times required for the formation of the different phases decrease as the BPR increases;but their sequence is *** on this infor- mation,“milling maps”which describe phase formation as a function of the BPR and milling time are con- *** from the milling balls increased as the BPR was increased.

关键词： Mechanical alloying Titanium alloys Structure evolution Process variables Milling maps

Towards a Medium/High Load-Bearing Scaffold fabrication System

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Tsinghua Science and Technology 2009年第S1期14卷 13-19页

作者： GIBSON Ian SAVALANI Monica M LAM Christopher X f OLKOWSKI Radoslow EKAPUTRA Andrew K TAN Kim Cheng HUTMACHER Dietmar W faculty of Engineering National University of Singapore Department of Biophysics and Human Physiology Medical University of Warsaw Warsaw 02-091 Poland Temasek Engineering School Temasek Polytechnic Institute of Health and Biomedical Innovation Queensland University of Technology Brisbane QL-4000 Australia

This paper describes fabrication of scaffolds for load-bearing applications, with primary consideration from the manufacturing perspective. An extrusion device, inspired by the fDM process, was used to create scaffolds from a variety of different polymeric materials and mixtures. The effectiveness of these scaffolds to host cells for bone regeneration has been investigated. This ongoing work has generated significant insight into the future direction of research and the possibilities of developing scaffolds for medium/high load-bearing applications.

关键词： tissue engineering load-bearing bone engineering scaffolds

fucoidan and topography modification improved in situ endothelialization on acellular synthetic vascular grafts

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生物活性材料(英文) 2023年第4期22卷 535-550页

作者： Yuan Yao Aung Moe Zaw Deirdre E.J.Anderson YeJin Jeong Joshua Kunihiro Monica T.Hinds Evelyn K.f.Yim Department of Chemical Engineering University of Waterloo200 University Avenue WestWaterlooONN2L 3G1Canada Department of Biomedical Engineering Oregon Health&Science UniversityPortlandOR97239USA Waterloo Institute for Nanotechnology University of Waterloo200 University Avenue WestWaterlooONN2L 3G1Canada Center for Biotechnology and Bioengineering University of Waterloo200 University Avenue WestWaterlooONN2L 3G1Canada

Thrombogenesis remains the primary failure of synthetic vascular *** coverage is crucial to provide an antithrombogenic ***,most synthetic materials do not support cell adhesion,and transanastomotic endothelial migration is ***,a surface modification strategy using fucoidan and topography was developed to enable fast in situ endothelialization of polyvinyl alcohol,which is not endothelial *** three different immobilization approaches compared,conjugation of aminated-fucoidan promoted endothelial monolayer formation while minimizing thrombogenicity in both in vitro platelet rich plasma testing and ex vivo non-human primate shunt *** of six topographical patterns showed that 2μm gratings increased endothelial cell migration without inducing inflammation responses of endothelial *** studies demonstrated that fucoidan could attract fibronectin,enabling integrin binding and focal adhesion formation and activating focal adhesion kinase(fAK)signaling,and 2μm gratings further enhanced fAK-mediated cell *** a clinically relevant rabbit carotid artery end-to-side anastomosis model,60%in situ endothelialization was observed throughout the entire lumen of 1.7 mm inner diameter modified grafts,compared to 0%of unmodified graft,and the four-week graft patency also *** work presents a promising strategy to stimulate in situ endothelialization on synthetic materials for improving long-term performance.

关键词： Blood-contacting devices Small diameter vascular graft Endothelialization Topography fucoidan