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中国与非洲（法文版） 2024年第6期16卷 60-61页

Le chemin de fer Éthiopie-Djibouti,d'une longueur de 752 km et construit par la Chine,a jouéun rôle clédans le trans-port régional depuis le deébut de ses opérations commerciales en janvier 2018.Le 17 mai dernier.

关键词： const chemi commercial

Meat quality traits of four Chinese indigenous chicken breeds and one commercial broiler stock

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第10期14卷 896-902页

作者： Rong-fa GUAN Fei LYU Xiao-qiang CHEN Jie-qing MA Han JIANG Chao-geng XIAO Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine China Jiliang University College of Biological and Environmental Engineering Zhejiang University of Technology Hubei University of Technology Food Science Institute Zhejiang Academy of Agricultural Sciences

Meat quality traits of four genotypes of Chinese indigenous chicken [Ninghai chicken(NC),frizzle chicken(FC),Ninghai xiang chicken(XC),and Zhenning loquat chicken(LC)] and one genotype of commercial broiler [Arbor Acres plus broiler(AAB)] were analyzed.The indigenous chickens were raised before the commercial chickens in order to achieve the same final processed days.Indigenous chickens of NC,FC,XC,and LC showed significantly higher inosine-5′-monophosphate(IMP) content,shorter fiber diameter,and lower shear force than those of AAB(P0.05).The indigenous chickens from FC displayed the highest total lipid content in the five bird genotypes(P<0.05).Significant differences of pH,color values of L* and a*,and drip loss for the five genotypes of birds were also observed.In conclusion,there were significant differences in the meat quality traits of the bird breeds selected in this study,and the indigenous chickens,especially the NC genotype,produced better quality meat as far as the IMP content,fiber diameters,and shear forces were concerned.

关键词： Indigenous chicken commercial broiler Meat quality Fiber diameter Inosine-5′-monophosphate

Vee-tail conceptual design criteria for commercial transport aeroplanes

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Chinese Journal of Aeronautics 2019年第3期32卷 595-610页

作者： Alejandro SANCHEZ-CARMONA Cristina CUERNO-REJADO Faculty of Aerospace Engineering Department of Aircraft and Spacecraft Technical University of Madrid (Universidad Poltécnica de Madrid)

Vee-tail configuration is an unconventional tail configuration for commercial transport aviation, the use of which could suppose reductions on CO2 emissions. The conceptual design criteria have been selected inspired on the certification requirements established by the aviation regulation in force. They are static stability in cruise, control after Critical Engine Failure(CEF),control in crosswind landing, and trim in these three conditions. The study is carried out through a combination of semi-empirical techniques and Vortex-Lattice Methods(VLM) and thus this analyses the consequences of applying these criteria to a reference aeroplane substituting its conventional tail by a parametrised Vee-tail configuration. The Vee-tail is defined by four parameters:span, root chord, taper ratio and dihedral angle. The results of the study establish a relation between the parameters in order to accomplish the proposed conceptual design criteria. To sum up, minimum and maximum limits are obtained for dihedral angle depending on the combination of the rest of parameters. In addition, a design restriction to the yawing trailing-edge tail control is reached when the results are analysed, demonstrating that its minimum size must be between 60%and 80% of the half-span of the tail, depending on the Vee-tail geometry.

关键词： commercial transport aeroplane Conceptual aircraft design Tail design requirements Unconventional tail design Vee-tail

Surface nanocrystallization of commercial pure titanium by shot peening

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 204-209页

作者： MA Guang LUO Yu CHEN Chun-huan REN Rui-ming WU Wei LI Zhi-qiang ZENG Yan-song School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China Beijing Aeronautical Manufacturing Technology Research Institute Beijing 100024 China Beijing Aeronautical Manufacturing Technology Research Institute Beijing 100024 China Beijing Aeronautical Manufacturing Technology Research Institute Beijing 100024 China

The surface nanostructures of commercial pure titanium was realized by the modified shot peening equipment commonly used in industry through the special treatment process. The results show that high-energy-shot-peening(HESP) commonly used to prepare nanostructured surface layers can be achieved by the increase of pill size, pill speed, and treatment time in the commercial shot peening equipment. XRD, SEM and TEM were used to characterize the surface layer microstructure of treated specimens. The analytic results show that the main deformation mode of commercial pure Ti is twinning. At the beginning of deformation, the dislocations are formed and twins occur within or on plane, then twins in intersection plane appear, and at last the twin characteristics disappear in the surface layer after longer treatment time. The deformation layer depth increases with treatment time in a certain period when the pill size and speed are unchanged. And in the severe plastic deformation (SPD) layer in which the twins are not identified easily by using SEM, the nanocrystalline microstructures are found under TEM. The finest grain size in the surface layer is about 40 nm, and the depth of nanostructured layers is over 60 μm. The microhardness of the nanostructured surface layers is enhanced significantly after shot peening compared with that of the initial simple.

关键词： surface nanocrystallization commercial pure titanium peening hardness

Tribological Characterization of commercial Pure Titanium Processed by Multi-Directional Forging

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Acta Metallurgica Sinica(English Letters) 2019年第7期32卷 857-868页

作者： I. Ansarian M. H. Shaeri M. Ebrahimi P. Minarik Department of Materials Science and Engineering Imam Khomeini International University (IKIU) P.O. Box 34148-9681 & Qazvin Iran Department of Mechanical Engineering Faculty of Engineering University of Maragheh P.O. Box 55136-533 Maragheh Iran Department of Physics of Materials Faculty of Mathematics and Physics Charles University Prague Czech Republic

This work discusses tribological properties of commercial pure (CP) titanium processed by multi-directional forging (MDF) up to six passes at room temperature and 220 ℃. For this purpose, wear test was conducted by dry sliding pin-on-disk method on the initial and ultrafine grained samples using different stress magnitudes of 1, 1.5 and 2 MPa. The results showed that wear resistance of CP titanium increases after the first pass of MDF in comparison with the initial condition, irrespective of the applied normal stress. For example, the average wear rate of MDFed samples was decreased about 30% and 24%, after first pass at room temperature and 220 ℃, respectively. However, average wear rate of the samples processed by six MDF passes was reduced about 40% at lower normal loads;it was increased about 9% at higher ones as compared to the initial condition. It was also found that the dominated wear mechanisms were abrasive and delaminated at the lower stresses, while the delamination mechanism was intensified and a slight adhesion was observed during the higher applied normal loads.

关键词： Multi-directional forging commercial pure titanium Tribological behavior Wear mechanisms

Surface nanostructures in commercial pure Ti induced by high energy shot peening

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 215-218页

作者： CHEN Chun-huan REN Rui-ming ZHAO Xiu-juan ZHANG Yu-jun School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China

The high-energy shot peening (HESP) technique was used to obtain the surface nanocrystalline microstructure for a hcp metal titanium. XRD, SEM and TEM were applied to characterize the microstructure of the surface layer. Large amount of the deformation twins in the surface layer were observed by SEM in the specimens after HESP treatment in a shot-time, and the number of deformation twins both in a single plane and in intersecting planes increases with HESP time, until the twin character disappears completely in the top surface layer, which means that the severe plastic deformation(SPD) occurs on the surface. The XRD analysis results show that after HESP treatmen for 30 - 60 min the surface grain size decreases to nanoscale. According to the TEM images and corresponding diffraction patterns from SPD areas of the 120 min-treatment specimen, the measured grain size near the surface is about 20 - 30 nm. The grain size in deformation layer increases with the depth from the surface, and the nanostructured layer is about 20 μm in depth. Therefore, the surface nanocrystalline and a gradient microstructure from the surface to the matrix are obtained, which results in the micro-hardness decreasing from surface to the matrix gradually.

关键词： surface nanocrystallization shot peening commercial pure Ti

Formation of graphene oxide from carbon rods of zinc-carbon battery wastes by audiosonic sonication assisted by commercial detergent

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Nanotechnology and Precision Engineering 2019年第2期2卷 89-94页

作者： Wipsar Sunu Brams Dwandaru Lia Desi Parwati Rhyko Irawan Wisnuwijaya Physics Education Department Faculty of Mathematics and Natural Sciences Universitas Negeri Yogyakarta Karangmalang Complex

This study aims to determine the effect of audiosonic sonication in normal modes on the formation of graphene oxide(GO)fromcarbon rods of zinc-carbon(ZnC)battery wastes.The method used in this study was sonication with an audiosonic frequency in normal modes,assisted by a surfactant solution derived from a commercial detergent.A graphite-detergent solutionwas exposed to audiosonicwaves using a frequency of 170 Hz for 3 hwith a pattern on the surface of the solution.The graphite solution was a mixture of 0.8 g of graphite powder and 100 ml of distilled water that was mixed using a blender for 2 min.25 ml of the solution was then taken and dripped with two drops of detergent solution containing 0.2 g detergent powder dissolved into 100 ml distilled water,so that a graphite-detergent solutionwas obtained.The tools used in this study included UV–Visible spectroscopy(UV–Vis),Fourier TransformInfraRed spectroscopy(FTIR),and a Scanning Electron Microscope(SEM).The solution that was audiosonicated showed a strong visible nodal pattern on its surface.The UV–Vis spectroscopy produced absorbance peaks at wavelengths of 225 nmand 270 nm,and the FTIR indicated the presence of OH and C_C functional groups,which suggested the existence of GO.The SEMimages showed GO in the formof coral-like materials.

关键词： Audiosonic sonication commercial detergent Graphene oxide ZnC battery

Distribution of stem decay in the beech trees of the Azerbaijan and its impact on the output of commercial wood

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Journal of Forestry Research 2019年第3期30卷 1023-1028页

作者： A.B.Yakhyaev V.S.Farzaliyev E.P.Safarova Azerbaijan University of Architecture and Construction Mammad Rahim StreetBaku City 1004Azerbaijan Republic Central Botanical Garden of Azerbaijan National Academy of Sciences Mikayil Mushfig 103Baku City 1004 Azerbaijan Republic

To determine the distribution of stem decay in the beech stands of Azerbaijan, we sought to identify the species, number, and height of attachment of fruiting bodies;the extent of decay in tree trunks growing under different conditions;and its influence on the trees’ commercial wood. The research was conducted on three farms representing the most common forest types of the Greater Caucasus within Azerbaijan. Examination of the presence of fruiting bodies in the tree trunk revealed that stem decay is the most common infection in beech (Fagus orientalis) stands, especially in fresh, moist areas, with less infection under dry growing conditions. In this work, the length, diameter, and volume of decay were studied by infecting the trunks of 93 model trees affected with mushrooms in 1–4 m cuttings. Our results showed that as the age of the stand increased, extent, diameter, and volume of decay increased significantly: the extent of decay from 1.47 to 6.43 m;the diameter of the decay from 8.15 to 32.7 cm;and the volume of decay from 2.5 to 13.2%. The relationship between age and the specified indicators is presented graphically. Using data obtained from the same sample of trees, we determined the expected and actual yield of commercial wood by age class. We determined that stem decay in beech stands leads to a decrease in the yield of commercial wood on average from 25.1% in the middle-aged to 14.8% in overmature plantations, respectively, with an estimated yield of 40.8–62.7%. Here we present mathematical models of the output of commercial wood from the infected part of the stands by age classes with the use of average data on the extent of decay in model trees.

关键词： Beech Wood Infection Forest type Stem decay Output of commercial wood Fruiting bodies

Late-entry commercial thinning effects on Pinus banksiana:growth, yield, and stand dynamics in Québec, Canada

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Journal of Forestry Research 2019年第1期30卷 95-106页

作者： Martin-Michel Gauthier Stéphane Tremblay Ministère des Forêts de la Faune et des Parcs du Québec Natural Resources Canada Canadian Forest Service

We studied late-entry commercial thinning effects on growth, yield, and regeneration in a 48-year-old jack pine(Pinus banksiana Lamb.) stand. Applied thinning intensities were 27, 32, and 47% of merchantable basal area(BA) excluding skidding trails. After 15 years, mean diameter at breast height of surviving trees in the 47% BA removal increased by 4.9 cm(25%) compared to the unthinned control. The 47% BA removal also increased gross merchantable volume(GMV) tree-1by 46% compared to the control. The 27% BA removal had twice as much GMV ha-1compared to the 47% BA removal after15 years. Moreover, cumulative GMV ha-1was much higher in the 27% BA removal than in the unthinned control. The highest thinning intensity produced larger trees on average, while the lowest thinning intensity maximized volume production per hectare. Maintenance of acceptable growing stock throughout the 15-year period in the 27% BA removal could provide other ecosystem functions such as biodiversity enhancement or wildlife habitat by delaying senescence. Regeneration data showed that a shift in species composition occurred in the understory. After 15 years, the understory was dominated by black spruce(Picea mariana(Mill.) B.S.P.), white birch(Betula papyrifera Marsh.), and trembling aspen(Populus tremuloides Michx.). If regenerating jack pine is an objective after final overstory removal, additional efforts will be needed to re-establish this species.

关键词： Jack pine commercial thinning Stand yield Succession Delayed senescence Tree regeneration