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Acta Geologica Sinica(English Edition) 2012年第1期86卷 73-84页

作者： NjANKO Théophile FOZING Eric Martial KWéKAM Maurice YAKEU SANDjO angéline Flore NjONFang Emmanuel Laboratory of Environmental Geology Department of Earth SciencesDschang University Laboratory of Geology ENS Yaounde I University

The Fomopea granitic pluton is emplaced in gnessic and amphibolitic basement. These gneissic and amphibolitic basement rocks are represented in the pluton＇s body as sub-rounded, elongated or stretched xenoliths. Amphibolitic xenoliths display testimonies of two main tectonic events namely：（i） El flattening deformation event characterized by a NW-SE to E-W foliation with a best pole at 246/57 and a mineral stretched lineation with a best line at 293/47; and （ii） E2 compressive event typified by （1） N-S to NNE-SSW steeply dipping foliation; （2） S-type flexion-fold indicating a sinistral shear movement. These amphibolite rocks indicate a magnetic susceptibility magnitude （Km） range from 418 ~SI to 90092 IISI for 87% of the stations showing a ferromagnetic behavior. K-T curves reveal the presence of Ti-poor magnetite as susceptibility mineral carrier. Magnetic foliation and lineation suggest that the N-S strike direction observed in the Bamendou amphibolite is, as pointed out elsewhere in the Central African Fold Belt, of paramount importance in the tectonic evaluation of the Fomopea area, since it has most likely acted as major deformation phase in the second tectonic event in the belt.

关键词： amphibolite anisotropy of magnetic susceptibility (AMS) Pan-African fold belt Cameroon

MicroRNA target prediction based on second-order Hidden Markov Model

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Frontiers in Biology 2010年第2期5卷 171-179页

作者： Song GAO Liangsheng ZHang Diangang QIN Tienan FENG yifei Wang Department of Mathematics School of SciencesShanghai UniversityShanghai 200444China School of Life Sciences Institute of Plant BiologyFudan UniversityShanghai 200433China

MicroRNAs are one class of small singlestranded RNA of about 22 nt serving as important negative gene *** animals,miRNAs mainly repress protein translation by binding itself to the 3'UTR regions of mRNAs with imperfect complementary *** bioinformatics investigations have resulted in a number of target prediction tools,all of these have a common shortcoming—a high false positive ***,it is important to further filter the predicted *** this paper,based on miRNA:target duplex,we construct a second-order Hidden Markov Model,implement Baum-Welch training algorithm and apply this model to further process predicted *** model trains the classifier by 244 positive and 49 negative miRNA:target interaction pairs and achieves a sensitivity of 72.54%,specificity of 55.10%and accuracy of 69.62%by 10-fold crossvalidation *** order to further verify the applicability of the algorithm,previously collected datasets,including 195 positive and 38 negative,are chosen to test it,with consistent *** believe that our method will provide some guidance for experimental biologists,especially in choosing miRNA targets for validation.

关键词： microRNA target gene experimentally supported targets second-order Hidden Markov Model forward algorithm

Twin crystal structured Al-10 wt.% Mg alloy over broad velocity conditions achieved by high thermal gradient directional solidification

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journal of Materials Science & Technology 2021年第12期71卷 152-162页

作者： Luyan Yang Shuangming Li Kai Fan Yang Li Yanhui Chen Wei Li Deli Kong Pengfei Cao Haibo Long ang Li Institute of Microstructure and Properties of Advanced Materials Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing100124China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum Jülich52428JülichGermany

Twin crystal structured Al-10 wt.% Mg alloys that were grown over a broad solidification velocity range were prepared and studied for the first *** high thermal gradient(G)and growth velocity(V)of directional solidification resulted in the dominant solidification of twins:the twinned dendrite trunks at constant high Vs curved in the G direction with large angles in 7 mm diameter crucibles and invaded regular columnar grains because of a distinct kinetics growth *** deceleration experiments were designed to produce twin crystals that evolved with lower values of V(100,10,and 0.5μm/s)and had a structural coarsening *** cell growth in the absence of arms occurred at a growth velocity of 10μm/s.A coherency loss was observed at a growth velocity of 0.5μm/s with straight coherent twin boundaries turning into curved incoherent *** theoretical analyses were performed to understand the structural evolution of the *** results demonstrate the possibility of producing dense and controlled twin crystals in the Al-Mg system under most industrial production conditions;thus,this approach can be a new structural choice for designing Al-Mg-based alloys that have widespread commercial applications.

关键词： Directional solidification Aluminum alloy Microstructural evolution Feathery crystals Twinned dendrites

In Tempore Belli： Reflections on the Sense of the Universal in George Crumb＇s Music of the Vietnam War

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journal of Literature and Art Studies 2015年第7期5卷 531-543页

作者： Victor j. Rodriguez ang-Cheng Kris Ho University of Michigan-Shanghai jiao Tong University joint Institute Shanghai China Beijing Normal University-Hong Kong Baptist University United International College Zhuhai China

This paper proposes new ways to understand the sense of universality in music through a reflection and analysis of George Crumb＇s Black angels （Images 1）： Thirteen lmages from the Dark Land, one of the defining musical expressions of the Vietnam War era. It centers on an analysis of the relationship of the body/self to an ＂ecology of war＂ produced through Crumb＇s music that renders these selves indistinct within this musical geography. The selves that inhabit Black angels could be that of anybody in particular since Crumb seeks to invoke in his music the primeval experience of terror that inhabits in all of us as the inheritors of mankind＇s violence. This sense of the universal militates against the desirable qualities of popular music that rely on the production of autonomous and singular selves that make the distinction between enemy and friend possible and distinct. We focus on Crumb＇s use of archaisms, his construction of time in this piece, and the author＇s overall purpose to invoke a time of war rather than to reflect the conditions of war, in order to delineate the contours of the universal time and space producing the undifferentiated primeval self of war. We conclude that although Crumb＇s rejection of the national self deprives the piece of a salient place in the popular cannon of the war, it has left an intellectual legacy on the times of the Vietnam War that deserves to be preserved.

关键词： Crumb Black angels Vietnam war universal experimental music

Flexible mica films for high-temperature energy storage

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journal of Materiomics 2018年第3期4卷 173-178页

作者： Xinwei Xu Wenlong Liu Yi Li yifei Wang Qibin Yuan jie Chen Rong Ma Feng Xiang Hong Wang State Key Laboratory for Mechanical Behavior of Materials&School of Electronic and Information Engineering Xi'an Jiaotong UniversityXi'an 710049China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

Dielectrics used for energy storage are highly desired for power electronics and pulse power applications and the polymer capacitors are the main commercial ones *** development of flexible electronics and wearable devices require the relative materials being ***,high temperature resistance is also desired because of the rising demand for high power devices and large electricity under elevated *** polymer dielectrics for polymer capacitors are flexible but with relatively low working temperature normally less than 100℃.Therefore,fabricating a dielectric material to satisfy the flexibility and high working temperature simultaneously is still a great *** we propose one solution by demonstrating a hand-exfoliated fluorophlogopite film with micrometer scale *** which,the mica film with a thickness of around 10μm(Mica-10)exhibits the inorganic-like temperature stability even polymer-like *** 25℃to 200℃,Mica-10 has an energy density of around 11.27 j/cm^(3)with a variation within 2%,accompanied by a charge-discharge efficiency of around 95%at an electric field of 500 MV/***,the thin thickness makes Mica-10 flexible,enabling its excellent flexibility and *** work revives the traditional material,mica,providing a way for high-temperature energy storage applications.

关键词： Dielectric Mica Energy storage High temperature Flexible

High-performance and stable AgSbTe_(2)-based thermoelectric materials for near room temperature applications

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journal of Materiomics 2022年第6期8卷 1095-1103页

作者： Yi Wu Pengfei Qiu Yuan Yu yifei Xiong Tingting Deng Oana Cojocaru-Miredin Matthias Wuttig Xun Shi Lidong Chen State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Institute of Physics(IA) RWTH Aachen UniversityAachen52056Germany School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310024China Peter Grünberg InstitutedjARA-Institute Energy-Efficient Information Technology(PGI-10) Forschungszentrum Jülich GmbHJülich52428Germany

AgSbTe_(2)-based ternary chalcogenides show excellent thermoelectric performance at low-and middletemperature ranges,yet their practical applications are greatly limited by their intrinsic poor thermodynamic *** this work,we demonstrate that AgSbTe_(2)-based ternary chalcogenides can be stabilized for service below their decomposition threshold.A series of AgxSb_(2-x)Te_(3-x)(x=1.0,0.9,0.8 and 0.7)samples have been prepared by the melt-quenching *** them,phase pure Ag0.9Sb1.1Te2.1 is verified by comprehensive structural characterizations from macroscale by X-ray diffraction to microscale by energy-dispersive spectroscopy and then to sub-nanometer scale by atom probe *** composition is further chosen for the stability *** decomposition threshold of Ag_(0.9)Sb_(1.1)Te_(2.1)appears around 473 *** this temperature,the chemical compositions and thermoelectric properties are barely changed even after 720 h annealing at 473 *** figure-of-merit(zT)value of Ag_(0.9)Sb_(1.1)Te_(2.1)below the decomposition threshold is very competitive for real applications even compared with Bi_(2)Te_(3-)based *** average zT of Ag_(0.9)Sb_(1.1)Te_(2.1)at 300e473 K reaches 0.84,which is higher than most other thermoelectric materials in a similar temperature range,promising applications in miniaturized refrigeration and power generation near room temperature.

关键词： stability performance ternary

Drought fluctuations based on dendrochronology since 1786 for the Lenglongling Mountains at the northwestern fringe of the East Asian summer monsoon region

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journal of Arid Land 2016年第4期8卷 492-505页

作者： HOU Ying NIU Zhenmin ZHENG Fang Wang Nai'ang Wang jianyu LI Zhuolun CHEN Hongxiang ZHang Xuemin College of Earth and Environmental Sciences Ningxia University Center for Climate Change and Hydrologic Cycle in Arid Region College of Earth and Environmental ScienceLanzhou University

The Lenglongling Mountains （LLM） located in northeastern part of the Tibet Plateau, belong to a marginal area of the East Asian summer monsoon （EASM） and are sensitive to monsoon dynamics. Two tree-ring width chronologies developed from six sites of Picea crassifolia in the LLM were employed to study the regional drought variability. Correlation and temporal correlation analyses showed that relationships between the two chronologies and self-calibrated Palmer Drought Severity Index （sc_PDSI） were significant and stable across time, demonstrating the strength of sc_PDSI in modeling drought conditions in this region. Based on the relationships, the mean sc_PDSI was reconstructed for the period from 1786 to 2013. Dry conditions prevailed during 1817-1819, 1829-1831, 1928-1931 and 1999-2001. Relatively wet periods were identified for 1792-1795 and 1954-1956. Spatial correlations with other fourteen precipitation/drought reconstructed series in previous studies revealed that in arid regions of Northwest China, long-term variability of moisture conditions was synchronous before the 1950s at a decadal scale （1791-1954）. In northwestern margin of the EASM, most of all selected reconstructions had better consistency in low-frequency variation, especially during dry periods, indicating similar regional moisture variations and analogous modes of climate forcing on tree growth in the region.

关键词： dendrochronology East Asian summer monsoon region self-calibrated Palmer Drought Severity Index Lenglongling Mountains

Selective enhancement of green upconversion luminescence of Er-Yb:NaYF4 by surface plasmon resonance of W18O49 nanoflowers and applications in temperature sensing

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Chinese Physics B 2018年第9期27卷 151-156页

作者： ang Li jin-Lei Wu Xue-Song Xu Yang Liu Ya-Nan Bao Bin Dong School of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 China Department of Physics Dalian Maritime University Dalian 116026 China Key Laboratory of Photosensitive Materials and Device of Liaoning Province Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission School of Physics and Materials Engineering Dalian Minzu University Dalian 116600 China

The W（18）O（49） nanoflowers with a diameter of 500 nm are prepared by a facile hydrothermal method. The Er-Yb：NaYF4 nanoparticles are adsorbed on the petals（the position of the strongest local electric field on W（18）O（49） nanoflowers）.With a 976 nm laser diode（LD） as an excitation source, the selectively green upconversion luminescence（UCL） is observed to be enhanced by two orders of magnitude in Er-Yb： NaYF4/W（18）O（49） nanoflowers heterostructures. It suggests that the near infrared（NIR）-excited localized surface plasmon resonance（LSPR） of W（18）O（49） is primarily responsible for the enhanced UCL, which could be partly reabsorbed by the W（18）O（49）, thus leading to the selective enhancement of green UCL for the Er-Yb： NaYF4. The fluorescence intensity ratio is investigated as a function of temperature based on the intense green UCL, which indicates that Er-Yb： NaYF4/W（18）O（49） nanoflower heterostructures have good potential for developing into temperature sensors.

关键词： upconversion localized surface plasmon resonance Er-Yb: NaYF4/W18O49 temperature sensing

Non-epitaxial growth of highly oriented transition metal dichalcogenides with density-controlled twin boundaries

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The Innovation 2023年第6期4卷 30-37页

作者： juntong Zhu Zhili Hu Shasha Guo Ruichun Luo Maolin Yu ang Li jingbo Pang Minmin Xue Stephen j.Pennycook Zheng Li Zhuhua Zhang Wu Zhou School of Physical Sciences CAS Key Laboratory of Vacuum PhysicsUniversity of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Mechanics and Control for Aerospace Structures Key Laboratory for Itelligent Nano Materials and Devices of Ministry of Educationand Institute for Frontier ScienceNanjing University of Aeronautics and AstronauticsNanjing 210013China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Environmental Chemistry and Materials Centre Nanyang Environment and Water Research InstituteNanyang Technological UniversitySingapore 637141Singapore

Twin boundaries(TBs)in transition metal dichalcogenides(TMDs)constitute distinctive one dimensional electronic systems,exhibiting intriguing physical and chemical properties that have garnered significant attention in the fields of quantum physics and ***,the controlled manipula-tion of TBs in terms of density and specific atomic configurations remains a fomidable *** this study,we present a non-epitaxial growth approach that enables the controlled and large scale fabrication of homoge-neous catalytically active TBs in monolayer TMDs on arbitrary ***,the density achieved using this strategy is six times higher than that observed in convention chemical vapor deposition(CVD)-grown *** rigorous experimental analysis and multigrain Wulff construc tion simulations,we elucidate theroleof regulating themetal source diffusion process,which serves as the key factor for inducing the self-oriented growth ofTMD grains and the formation of unified ***,we demonstrate that this novel growth mode can be readily incorporated into the conventional CVD growth method by making a simple modification of the growth tempera-ture profle,thereby offering a universal approach for engineering of grain boundaries in two-dimensional materials.

关键词： grain transition tempera

Potential Use of Essentials Oils to Control Fruitlet Core Rot (FCR) in Pineapple (Queen Victoria Variety) in Reunion Island

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American journal of Plant Sciences 2020年第11期11卷 1671-1681页

作者： Marc Chillet angélique Hoareau Mathilde Hoarau jérome Minier CIRAD UMR QUALISUD 7 Chemin de l’IRAT 97410 Saint Pierre Ile de la Réunion France QUALISUD Univ. Montpellier CIRAD Montpellier SupAgro Univ. d’Avignon Univ. de la Réunion Montpellier France

Fruitlet Core Rot (FCR) is one of the major postharvest diseases of pineapple (Ananas comosus var. comosus), especially on the prone variety Queen Victoria cultivated in Reunion Island. This aggressive disease is generally due to two pathogens: Fusarium ananatum and Thalaromyces stolii, and needs to be controlled during postharvest. In Reunion Island, F. ananatum is the principal causal agent impacting fruit exportation. Fruit produced for the export market is generally treated with chemicals. This type of postharvest treatment is not in line with consumer expectations, as consumers prefer fruits treated with nonharmful and natural products. The objective of this work was to study alternative postharvest treatments using the fungitoxic properties of essential oils and their ability to elicit the resistance mechanisms of the fruit. Six EAs were tested in vitro on mycelial growth of F. ananatum. Whether by volatilization or included in the culture medium, some essential oils such as thymol, eugenol, geraniol and the carvone/menthol mixture have a strong fungistatic effect. But only thymol has a fungitoxic effect. The thymol, a natural molecule synthesized by thyme (Thymus vulgaris L. thymoliferum

关键词： Essential Oils Fruitlet Core Rot Pineapple Postharvest Treatment Thymol