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Deformation twinning in octahe dron-base d face-centere d cubic metallic structures:Localized shear-force dipoles drive atomic displacements

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Journal of Materials science & Technology 2022年第31期126卷 116-126页

作者： Hengfei Gu Chengze Liu Fusen yuan Fuzhou Han yingdong Zhang Muhammad Ali Wenbin Guo Jie Ren Lifeng Zhang songquan Wu Geping Li Institute of Metal Research Chinese Academy of SciencesShenyang 110016China University of chinese Academy of sciences Beijing 100049China University of science and Technology of China Hefei 230026China Institute of Molecular Plus Tianjin UniversityTianjin 300072China school of Materials science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China

Twinning is found to impart favorable mechanical,physical and chemical properties to nanostructured materials.Deformation twinning prevails in face-centered cubic(FCC)nanocrystalline materials upon loading.In FCC structures,the{111}deformation twinning is traditionally believed to nucleate and grow through layer-by-layer emission of 1/6shockley partial dislocations on consecutive{111}planes.We report that deformation twinning is able to occur in crystalline(Fe,Nb)_(23)Zr_(6)nanoparticles(NPs)that have a large Mn 23 Th 6-type FCC structure with a Zr-octahedron as a motif.Based on direct atomic-scale observations,we discover a new zero-net-strain path for the{111}deformation twin-ning in FCC structures.To form a[¯1¯12]/(111)twin,for example,short(¯1¯11)planes within two adjacent(111)plane layers in the repeated three-layer sequence of(111)planes are shear deformed continuously by a shear-force dipole along the[11¯2]direction like a domino effect,whereas the other(111)plane in the repeated sequence remains intact.In addition,a loading criterion for deformation twinning of a FCC NP under uniaxial compression is proposed based on our observations.Our work here not only extends the fundamental understanding on deformation twinning in FCC structures,but also opens up studies of deformation behaviors in a class of Mn 23 Th 6-type FCC materials.

关键词： deformation cubic dipole

Germacranolide sesquiterpenes from Carpesium cernuum and their anti-leukemia activity

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chinese Journal of Natural Medicines 2021年第7期19卷 528-535页

作者： yAN Chen LONG Qun ZHANG yun-Dong BABU Gajendran KRIsHNAPRIyA Madhu Varier QIU Jian-Fei sONG Jing-Rui RAO Qing yI Ping sUN Mao LI yan-Mei Department of Pharmacy An Shun City People’s HospitalAnshun 561000China Key Laboratory of Chemistry for Natural Products of Guizhou Province and chinese Academic of sciences Guiyang 550014China state Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Department of Medical Biochemistry Dr.ALM PGIBMSUniversity of MadrasTaramani CampusChennaiIndia

In this study,three new germacranolide sesquiterpenes(1–3),together with six related known analogues(4–9)were isolated from the whole plant of Carpesium cernuum.Their structures were established by a combination of extensive NMR spectroscopic analysis,HR-EsIMs data,and ECD calculations.The anti-leukemia activities of all compounds towards three cell lines(HEL,KG-1a,and K562)were evaluated in vitro.Compounds 1–3 exhibited moderate cytotoxicity with IC50 values ranging from 1.59 to 5.47μmol·L^(−1).Mechanistic studies indicated that 2 induced apoptosis by decreasing anti-apoptotic protein Bcl-2 and activating the caspase family in K562 cells.These results suggest that compound 2 is a potential anti-leukemia agent.

关键词： Carpesium cernuum Germacranolides Anti-leukemia K562 MAPK

History and conservation of wild and cultivated plant diversity in Uganda： forest species and banana varieties as case studies

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植物分类与资源学报 2016年第1期38卷 26-52页

作者： Alan C. Hamilton Deborah Karamura Esezah Kakudidi Honorary professor Kunming Institute of Botany Chinese Academy of Sciences Heilongtan Kunming 650201 China Bioversity International Uganda Office PO Box 24384 Kampala Uganda Department of Botany Makerere University PO Box 7062 Kampala Uganda

The history of wild and cultivated plant diversity in Uganda is reviewed,taking forest species and bananas as examples. Palynological research into past human influences on forests is reassessed. The evidence suggests that crops were first introduced into the country at about 1,000 BCE,farming communities practicing slash and burn agriculture started to significantly influence the floristic composition of forests during the 1st millennium BCE and there was a major episode of forest reduction at about 1,000 CE related to socio-economic change. Bananas were probably introduced in the early centuries CE. The colonial era from 1894 saw the introduction of new concepts of land ownership and the establishment of forest reserves and agricultural stations. Forests and banana diversity are currently under threat,Uganda having a very high rate of deforestation and endemic banana varieties proving susceptible to introduced pests and diseases. It is suggested that,under these circumstances,conservationists take an opportunistic approach to field engagement,making use of favourable local conditions as they arise. Partnerships should be sought with elements of society concerned with sustainable use,provision of ecosystem services and cultural survival to widen the social base of plant conservation. International organisations involved in conservation of plant genetic resources and wild plant species should collaborate with one another to develop the conceptual basis of plant conservation,to make it more relevant to countries like Uganda.

关键词：植物学植物分类植物生态学植物演化

subseasonal features of the Asian summer monsoon in the NCEP climate forecast system

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Acta Oceanologica sinica 2008年第3期27卷 88-103页

作者： song yANG WEN Min R Wayne HIGGINs NOAA＇s Climate Prediction Center Camp Springs Maryland 20746 USA chinese Academy of Meteorological sciences Beijing 100081 China

The operational climate forecast system （CFs） of the Us National Centers for Environmental Prediction provides climate predictions over the world, and CFs products are becoming an important source of information for regional climate predictions in many Asian countries where monsoon climate dominates. Recent studies have shown that, on monthly-to-seasonal time-scales, the CFs is highly skillful in simulating and predicting the variability of the Asian monsoon. The higher-frequency variability of the Asian summer monsoon in the CFs is analyzed, using output from a version with a spectral triangular truncation of 126 waves in horizontal and 64 sigma layers in vertical, focusing on synoptic, quasi-biweekly, and intraseasonal time-scales. The onset processes of different regional monsoon components were investigated within Asia. Although the CFs generally overestimates variability of monsoon on these time-scales, it successfully captures many major features of the variance patterns, especially for the synoptic timescale. The CFs also captures the timing of summer monsoon onsets over India and the Indo-China Peninsula. However, it encounters difficulties in simulating the onset of the south China sea monsoon. The success and failure of the CFs in simulating the onset of monsoon precipitation can also be seen from the associated features of simulated atmospheric circulation processes. Overall, the CFs is capable of simulating the synoptic-to-intraseasonal variability of the Asian summer monsoon with skills. As for seasonal-tointerannual time-scales shown previously, the model is expected to possess a potential for skillful predictions of the high-frequency variability of the Asian monsoon.

关键词： Asian summer monsoon onset evolution synoptic-to-intraseasonal variability NCEP climate prediction system

Medicinal Mushroom Products:Nutriceuticals and/or Pharmaceuticals?

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食用菌学报 2009年第4期16卷 80-86页

作者： CHANG shuting Emeritus professor of Biology The Chinese University of Hong Kong Shatin N. T. Hong Kong SAR China

Although the effectiveness of mushroom products(mushroom derivatives) has been confirmed repeatedly by numerous laboratory experiments and,in some cases,human trials,precisely how these products work is still a matter of conjecture.studies on the effectiveness of mushroom products fall into two general categories.One approach has been to isolate and determine the bioactivity of individual mushroom components within a particular class of compounds(e.***.polysaccharides,lectins,triterpenoids,fungal immunomodulatory proteins).The active principal component is then sold in refined or purified form,e.***.the polysaccharide lentinan from the edible/medicinal mushroom Lentinula edodes.such an approach is certainly valid if the objective is to focus on a single mushroom-derived substance for the treatment of specific disease conditions,e.***.cancers or strokes.In such cases,the products might be(and have been) developed and marketed as prescription drugs.However,an alternative approach is not to focus on a single component within a class of compounds but on groups of compounds that improve overall health and the general quality of life.These composite formulae,in which several different compounds together contribute to the beneficial effect of the mushroom,could then be used collectively as a dietary supplement(nutriceutical).Thus,the medicinal effects afforded by medicinal mushroom products may be attributable to several quite different types of compounds present in the mushrooms,e.***.polysaccharides,lectins,triterpenoids and fungal immunomodulatory proteins.These compounds,and possibly others yet to be identified,appear to act in concert in contributing to the documented anticancer,antitumour,antiviral,antibacterial and immunomodulating properties of the mushroom.Therefore,mushroom nutriceuticals may be deemed to have multifunctional values,the essence of which depends on the integrated effects of the various compounds.Certainly,the overwhelming majority of mushroom-based products currently available are not single components

关键词：扁圆头铆钉药物内科学医药品

China-U.s. Economic symbiosis Moving toward symmetry

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China International studies 2010年第2期30卷 126-139页

作者： Tang Xiaosong Deng Fengjuan professor at Department of Diplomacy School of Legal Studies Guangdong University of Foreign Studies Guangdong University of Foreign studies

The symbiotic relationship between the chinese and U.s. economies determines that the two countries have mutual strategic needs.For a long time,the United states has played a dominant role in this relationship,yet it has also been developing in a direction favorable to China.The current financial crisis has accelerated the development of this trend,which gives China more say and makes the United states give up its previous dominant posture and seek to build a more reliable and new pattern of relationship in which the two are in the same boat.

关键词：共生关系中国对称性经济金融危机发言权美国

young American China Watchers Views on China

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Contemporary International Relations 2008年第1期18卷 44-61页

作者： Zhang Zhixin Assistant Research professor of the Institute of American studies CICIR

In this paper,the author has made a thorough study over the new generation of American China Watchers.Most of the pages are devoted to a detailed comparison between the old generation and the young generation of American China Watchers regarding to their background,education,and views over China.At the end of the paper,the author also gives some policy suggestions for both the chinese and U.s. government based on the findings in this study.

关键词：中国美国外交关系政策研究

Capital deepening: the only way towards higher productivity and income

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China Economist 2009年第4期4卷 112-120页

作者：殷醒民 professor with China Center for Economic studies Fudan University

Technological progress is the main driver of labor productivity in manufacturing industries. But it is capital accumulation that makes such progress possible. In the early 21st century, China’s manufacturing entered a process of capital deepening, in which labor productivity improvement is based on the increase of per capita assets. Capital accumulation in technical industries has created higher labor productivity and enabled phenomenal growth of new technology industries, contributing to the rapid and all-round growth of manufacturing industries as a whole. This is the real premise of China’s sustained economic growth over the past ten years.

关键词： Capital accumulation Manufacturing structure Economic growth sector advantage

Impact of the chinese Model in Africa

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China International studies 2009年第2期29卷 16-29页

作者： Tao Wenzhao professor at the school of Marxism studies Renmin University of China

The chinese model has a fairly big influence in Africa.Ever since reform and opening-up,China has been focusing on the central task of economic construction,which brought rapid economic growth,strengthening comprehensive national power, improving lives of the people and extending international influence.The success of the chinese model has aroused much interest in the world,especially Africa,and produced positive effects.It is the outcome of a combination of several factors, such as the attraction of China's development.the impetus produced by that development and the appeal of China's friendly policies.Nevertheless,China is not going to sell its model and ultimately Africa has to carve out its own way of development.

关键词：中国对外关系非洲外交