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Acta Metallurgica Sinica(English Letters) 2021年第2期34卷 196-204页

作者： S.bi b.L.Xiao Z.H.Ji b.S.Liu Z.y.Liu Z.y.Ma Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Material Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China AVIC Manufacturing Technology Institute Beijing 100024China

High-energy ball milling(HEbM)combined with powder metallurgy route was used to fabricate carbon nanotube(CNT)reinforced 7055 Al *** powder morphology evolution processes(HEbM-1 and HEbM-2)were designed to investigate the dispersion and damage of CNTs during HEbM ***-1 evolution process involved powder fl attening,cold-welding and fracture,while HEbM-2 evolution process consisted of powder fl attening and *** HEbM-1,the repetitive fracture and cold-welding process was effective for dispersing ***,the powder fl attening process in HEbM-2 was unsuccessful in dispersing CNTs due to two reasons:(1)the thickness of fl aky Al powders exceeded the critical value,and(2)the clustered CNTs embedded in fl aky Al powders could not be *** of the broadening of D band and the appearance of a new defect-related D’band,product of I D/I G and full width half maximum of D band,rather than I D/I G,was used to evaluate the actual damage of *** indicates that the damage of CNTs was severe in powder fl attening and fracture stages,while the damage of CNTs was small in powder cold-welding stage.

关键词： Metal matrix composites Carbon nanotubes Powder evolution Dispersion and damage Powder metallurgy

Study of Commercial Wheat Flour Milling Process:Relation of Flour yield,Ash and Protein Contents of Flour Mill and Characteristics of Wheat blend

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食品科学 2006年第11期27卷 146-152页

作者： y S Kim C W Deyoe O K chung E Haque Department of Grain Science and Industry Kansas State University (KSU) Manhattan 66506 Kansas StateU.S. Key Laboratory ofFood Science and Safety Ministry of Education School of Food Science and Technology Southern YangtzeUniversity Wuxi 214036 China Department of Grain Science and Industry Kansas State University (KSU) Manhattan 66506 Kansas StateU.S. Hard Winter Wheat Quality Laboratory Grain Marketing and Production Research Center AgriculturalResearch Service U.S. Department of Agriculture Manhattan 66502 Kansas State U.S.

The profit margin in the flour milling industry is quite narrow,so high-quality raw materials and efficiency of milling operations are crucial for every company. Many flour mills,especially those which import wheat from other countries and have limited storage space for the different varieties or classes of wheat,can not afford to buy low quality wheat. Consequently,a mathematical model which can test the impact and interactions of raw materials,in technical point of view,would be a useful decision-making tool for the milling industry. A flour miller tests wheat for physical and chemical characteristics,cleanness and soundness. The miller also performs experimental milling,if available,to have some idea how the given wheat will behave during commercial milling. based on these test results,the miller can only guess the commercial milling results such as flour yields and flour ash and protein contents. Thus,the objective of this study was to develop empirical equations to estimate commercial milling results,using the physical,chemical and experimental milling data of the given wheat blend and also,additionally,flour ash and protein specifications of the end-user. This was done by using the actual commercial milling procedures and their wheat physical,chemical,experimental milling data,and other vital data. Data were collected from a commercial mill located in East Asia that had four production lines and used wheat blend combinations from five different wheat classes,i.e. Hard Red Winter (HRW),Dark Northern Spring (DNS),Soft White (SW),Australian Soft (AS),and Australian Standard White (ASW) wheat to produce over 40 different products. The wheat physical and chemical characteristics included test weight,thousand kernel weight,ash and protein contents. The experimental milling data were straight-grade and patent flour yields,along with patent flour ash and protein contents from a buhler experimental mill. The commercial milling results included the flour yields of paten

关键词： Study of Commercial Wheat Flour Milling Process SFA bPP

Subchronic Oral Toxicity of Pyridostigmine bromide in Rats

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biomedical and Environmental Sciences 1991年第3期4卷 283-289页

作者： b.S.LEVINE R.LONG H.chung Department of Pharmacology University of Illinois at Chicago Chicago IL 60680Pathology Associates Inc. Chicago IL 60616Walter Reed Army Institute of Research WashingtonDC 20307

This study evaluated the oral toxicity of pyridostigmine bromide in Sprague-Dawley rats when administered for 13 weeks by daily gavage. Groups of 10 rats/sex received doses of 0, 5, 15, 30, or 60 mg/kg/day. Toxicity was limited to exaggerated cholinergic stimulation at doses of 15 mg/kg/day or greater. Significant findings included tremors and inhibition of RbC acetylcholinesterase. Thus, 5 mg/kg/day of pyridostigmine bromide appears to be the no observed toxic effect level under the conditions of the present investigation.

关键词： Subchronic Oral Toxicity of Pyridostigmine bromide in Rats

METASTAbLE PHASE SEPARATION OF Fe_(50)Cu_(50) HyPOPERITECTIC ALLOy UNDER SPACE SIMULATION CONDITIONS

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Acta Metallurgica Sinica(English Letters) 1999年第2期12卷 198-204页

作者： Lu, X.y. Cao, C.D. Wei, b.b. Northwestern Polytechnical Univ Xi'an China

A 3m drop-tube was used to investigate the solidification of Fe50Cu50 hypoperitectic alloy. The falling droplets solidified as spheres and splats. The obtained particles range from 1000μm to 80μm in diameter. It was found that the phase separation occurred if the Fe-Cu liquid was undercooled to a certain extent before *** the big particles macroscopic separation of Fe-rich phase always appeared in the cented of the particles, and in the small ones the Fe-rich phase usually solidified as little spheres. In the flakes the Fe-rich and Cu-rich layers alternatively displayed from top to bottom.

关键词： peritectic alloy phase separation dendrite growth drop tube

The genetics of race differentiation——should it be studied?

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National Science Review 2023年第4期10卷 6-7页

作者： chung-I Wu NSR School of Life Sciences Sun Yat-sen University

In this issue, NSR publishes an article entitled ‘Expression profiles of east-west highly differentiated genes in Uyghur genomes’ by Ning et al.(2023) [1]. briefly, it is about the regulation of gene expression in Uyghur genomes, which are admixed between Asian and European genomes. In evolutionary terms, this is a case of post-isolation secondary contact over a time span of thousands of years. In most other cases, such as African Americans, the admixture has a time span of years. Furthermore,

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ADDITIVE PERTURbATIONS OF LOCAL C-SEMIGROUPS

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Acta Mathematica Scientia 2015年第6期35卷 1566-1576页

作者： chung-Cheng KUO Department of Mathematics Fu Jen University

In this paper, we apply the contraction mapping theorem to establish some bounded and unbounded additive perturbation theorems concerning local C-semigroups. Some growth conditions of perturbations of local C-semigrou... 详细信息

关键词： local C-semigroup generator abstract Cauchy problem perturbation

New ommatids of Ommatinae(Coleoptera:Archostemata:Ommatidae)from the yixian Formation of western Liaoning,China

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Progress in Natural Science:Materials International 2007年第7期17卷 803-811页

作者： Shih chung Kun beijing 100037 Capital Normal University China Key Laboratory of Insect Evolution & Environment Change College of Life Science

Four new fossil species of the family Ommatidae from the yixian Formation of western Liaoning,China are described. Two of them belong to tribe brochocoleini:brochocoleus sulcatus *** brochocoleus angustus *** other two refer to tribe Ommatini:Cionocoleus planiusculus *** Cionocoleus cervicalis *** diagnosis of brochocoleus and Cionocoleus, respectively,are revised.A preliminary analysis of geographical distribution suggests a possible migration pathway of the genus bro- *** relationship between the genus Cionocoleus and the extant family Crowsoniellidae is briefly discussed.

关键词： Ommatidae brochocoleus Cionocoleus new species yixian Formation

Microstructural characteristics and mechanical properties of the hot extruded Mg-Zn-y-Nd alloys

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Journal of Materials Science & Technology 2021年第1期60卷 44-55页

作者： b.N.Du Z.y.Hu L.y.Sheng D.K.Xu y.X.Qiao b.J.Wang J.Wang y.F.Zheng T.F.Xi Shenzhen Institute Peking UniversityShenzhen 518057China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Jiangsu University of Science and Technology Zhenjiang 212003China Shenzhen yezhan Electronics Co. LtdShenzhen 518110China

A new type of Mg-Zn-y-Nd alloy for degradable orthopedic implants was *** the present study,the Zn and y content was adjusted and their influences on the microstructures and mechanical behaviors were discussed in *** results showed that the as-extruded Mg-Zn-y-Nd alloys are mainly composed of fine dynamic recrystallized grains(DRXed grains),la rge unDRXed grains and linearly distributed secondary *** cha nge of Zn content exerts little influence on the grain structure of the extruded Mg-Zn-y-Nd alloy,while the increase of y content would hinder the dynamic recrystallization process and the growth of the DRXed grains,thus the size and volume fraction of the equiaxed DRXed grains *** tensile and compressive properties are very little affected by Zn content because of the similar grain *** y content increases,the tensile yield strength(TyS) and ultimate strength(TUS) increase while the elongation decreases,this is caused by a combined strengthening effect of grain refinement,texture,precipitation and *** compressive yield strength(CyS) and ultimate strength(CUS) of Mg-Zn-y-Nd alloy with diffe rent y content exhibit a similar tendency as the tensile test.

关键词： Mg-Zn-y-Nd alloy Microstructure Tensile properties Compressive properties basal texture Twin

Forms and Aesthetics of bridges

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Engineering 2018年第2期4卷 103-112页

作者： Man-chung Tang Chinese Academy of Engineering Beijing 100088 China US National Academy of Engineering Washington DC 20001 USA T.y. Lin International Group San Francisco CA 94104 USA

The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple, original, and harmonious with its surroundings. Aesthetics is not an additional consideration in the design of a bridge, but is rather an integral part of bridge design. both the structural configuration and the aesthetics of a bridge must be considered together during the conceptual design stage. To achieve such a task, the bridge design engineer must have a good understanding of structural theory and bridge aesthetics.

关键词： Form Aesthetics bridge Concept Design Environment

A perturbation-incremental scheme for studying Hopf bifurcation in delayed differential systems

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Science China(Technological Sciences) 2009年第3期52卷 698-708页

作者： chung Kwok Wai Department of Mathematics City University of Hong Kong Kowloon

A new method, called perturbation-incremental scheme (PIS), is presented to investigate the periodic solution derived from Hopf bifurcation due to time delay in a system of first-order delayed differential equations. The method is summarized as three steps, namely linear analysis at critical value, perturba- tion and increment for continuation. The PIS can bypass and avoid the tedious calculation of the center manifold reduction (CMR) and normal form. Meanwhile, the PIS not only inherits the advantages of the method of multiple scales (MMS) but also overcomes the disadvantages of the incremental harmonic balance (IHb) method. Three delayed systems are used as illustrative examples to demonstrate the validity of the present method. The periodic solution derived from the delay-induced Hopf bifurcation is obtained in a closed form by the PIS procedure. The validity of the results is shown by their consis- tency with the numerical simulation. Furthermore, an approximate solution can be calculated in any required accuracy.

关键词： delayed differential equation perturbation-incremental scheme Hopf bifurcation synchronization center manifold