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Multi-factor Analysis of Reflection from Granite Surfaces

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Journal of China University of Mining and Technology 2007年第2期17卷 255-257页

作者： ZHAO Nai-zhuo YAN Lei ZHAO yun-sheng lv yun-feng WU Tai-xia College of Urban and Environmental Science Northeast Normal University Changchun Jilin 130024 China Beijing Key Lab of Spatial Information Integration and 3S Application Peking University Beijing 100871 China

Many earlier experiments have shown that reflection from rock surfaces depends upon surface roughness,in-cidence zenith angle,viewing zenith angle,incidence azimuth and viewing azimuth. However,no research exists show-ing the interaction effects of these variables. Using granite as a model surface,we have designed an orthogonal,two level test having seven factors. Analysis of variance shows that surface roughness,relative viewing azimuth,and the in-teraction between these two factors are the largest sources of variance in our experiment. Hence we should include the interaction term in reflection models of granite.

关键词： granite bidirectional reflectance mutual effect orthogonal test

Template-module assembly to prepare low-molecular-weight gene transport system with enhanced transmembrane capability

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Science China Chemistry 2014年第4期57卷 558-567页

作者： YANG Bin lv Yin WANG QingRong LIU yun AN Hong FENG Jun ZHANG XianZheng zhuo RenXi Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Construction Engineering Research Institute of the General Logistics Department

Based on specific host-guest interactions between amine-modified [3-cyclodextrin （CD-TAEA） and functional adamantane （AD） derivatives, a module-template strategy has been proposed for the construction of low-molecular-weight cationic assem- blies for gene transport. This strategy offers great flexibility in terms of the introduction of mono- or multi-functionality by the inclusion of one or more adamantane-based modules with the desired functionalities. As proof of concept, phenylboronic acid （PB） containing adamantane （PB-AD） was used as a model module in the hope of offering enhanced cytosolic delivery in con- sideration of the special affinity of PB groups with cell membranes. The physicochemical properties of the complexes formed with plasmid DNA, such as particle size, zeta potential and morphology were investigated. Confocal laser scanning microsco- py and flow cytometry experiments demonstrated the important contribution of the functional PB-AD module to the consider- ably enhanced intracellular internalization and uptake by cellular nuclei. Compared to the parent CD-TAEA, PB-AD/CD- TAEA assemblies mediated higher transfection rates, which were even comparable to that of PEI25K. In addition, PB-AD/CD- TAEA displayed much lower cytotoxicity than PEI25K in both 293T and HeLa cell lines. The encouraging results suggest that CD-TAEA can be developed as a powerful template capable of readily accommodating various AD-based modules giving versatile functionalities for improved transfection.

关键词： template-module assembly host-guest interaction gene delivery

Spin Caloritronic Transport of Tree-Saw Graphene Nanoribbons

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Chinese Physics Letters 2019年第1期36卷 48-51页

作者： Yu-zhuo lv Peng ZHAO School of Physics and Technology University of Jinan

Using density functional theory combined with non-equilibrium Green's function method, we investigate the spin caloritronic transport properties of tree-saw graphene nanoribbons. These systems have stable ferromagnetic ground states with a high Curie temperature that is far above room temperature and exhibit obvious spin-Seebeck effect. Moreover, thermal colossal magnetoresistance up to 1020% can be achieved by the external magnetic field modulation. The underlying mechanism is analyzed by spin-resolved transmission spectra, current spectra and band structures.

关键词： Spin Caloritronic Transport Tree-Saw Graphene Nanoribbons Density functional theory

Aflatoxin sufferer and p53 gene mutation in hepatocellular carcinoma

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World Journal of Gastroenterology 1998年第1期4卷 33-34页

作者： DENG zhuo-Lin MA yun 不详

IM To study the p53 gene mutation and its relationship to aflatoxin B1 exposure in hepatocellular carcinoma (HCC).METHODS Restriction fragment length polymorphism analysis method was used in 62 HCC samples, and DNA direct sequencing in another 45 HCC samples.RESULTS In HCC and AFB1 high and lowrisk areas, 36/52 (69%) and 2/10 (20%) cases were found losing the HaeⅢ allele respectively, suggesting one of the base G mutation at the p53 gene codon 249. Similar results appeared in DNA direct sequencing, 20/35 (57%) and 1/10 (10%) respectively mutated at the codon 249 third base G to C transversion.CONCLUSION In HCC after AFB1 exposure, mutation of p53 gene is fixed at codon 249 third base and take the form of G to T transversion. This is a definite marker of mutation which is induced by AFB1 mutagen. It is applicable for molecular epidemiologic survey of the sufferers of AFB1 among HCC cases and for discovering more unknown natural AFB1 contaminated areas..

关键词： Aflatoxin B1 genes,p53 mutation carcinoma,hepatocellular liver neoplasms

A porous high-entropy alloy for high-efficient oxygen evolution reaction

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Rare Metals 2023年第7期42卷 2174-2181页

作者： Wei Wang yun-zhuo Lu Xing Lu School of Materials Science and Engineering Dalian Jiaotong UniversityDalian116028China

Oxygen evolution reaction(OER)plays a crucial role in regulating the process of hydrogen production from water splitting where an expeditious,stable and low-cost electrocatalyst is urgently *** employing a facile strategy of selective phase dissolution,this dissertation attempts to illuminate the successful preparation of a porous AlCoCrFeNi high-entropy alloy(SPD-48 h).

关键词： alloy entropy evolution

Effects of Na_(2)CO_(3)on reduction mechanism and kinetics of iron during deep reduction of ilmenite concentrate

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Journal of Iron and Steel Research International 2023年第3期30卷 419-428页

作者： Xiao-dong lv You-ling Hou yun-tao Xin Wei lv Xue-wei lv Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

High-quality upgraded titanium slag obtained through semi-molten reduction with the addition of Na_(2)CO_(3)is important for the fluidizing chlorination process to produce TiO_(2)*** key is the effect of Na_(2)CO_(3)on the reduction behavior of ***,the effects of Na_(2)CO_(3)on reduction mechanism and kinetics of iron during deep reduction of ilmenite concentrate were *** results indicated that the metallization ratio of the reduced sample increased with increasing temperature,time,and dose of Na_(2)CO_(3).The addition of Na_(2)CO_(3)significantly accelerated the reduction of iron in the ilmenite concentrate and promoted the growth of iron ***,the addition of Na_(2)CO_(3)produced sodium iron titanates;thus,the metallization ratio of the sample decreased with an increase in the temperature and time when the temperature was above 1200℃and the time was more than 30 *** the doses of Na_(2)CO_(3)were 0,3,and 6 wt.%,the reduction of iron was controlled by the interfacial chemical reaction,both the interfacial chemical reaction and diffusion,and diffusion,respectively,and the apparent activation energies were 134.91,64.89,and 120.82 kJ/mol,respectively.

关键词： Ilmenite concentrate Sodium carbonate Metallization ratio Reduction mechanism Kinetics

A conifer-dominated Early Triassic flora from Southwest China

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Science Bulletin 2018年第22期63卷 1462-1463页

作者： zhuo Feng Haibo Wei yun Guo Benjamin Bomfleur Institute of Deep Time Terrestrial Ecology Yunnan UniversityKunming 650500China Research Center for Earth System Science Yunnan UniversityKunming 650500China Institute of Karst Geology Chinese Academy of Geological SciencesGuilin 541004China Forschungsstelle fur Paltiobotanik Westfalische Wilhelms-UniversitatHeisenbergstraβe 2Munster D-48149Germany

The end-Permian mass extinction is the greatest biotic crisis in Earth *** marine species (>95%)and many land tetrapods (>70%)disappeared within a very short time interval [1]. Previous studies of this dramatic event mainly have focused on evolutionary patterns in animal groups prior to the extinction, and on their recovery during the Early Triassic [2].Although some macroevolutionary scenarios have been postulated for the changes in land-plant vegetation through the Permian and Triassic,the severity of extinction and,the timing and radiation pattern in the recovery of plant groups during the Early Triassic are still debated [3].Hitherto there has been little information about plant life in the wake of the end-Permian extinction event,mainly because of the scarcity of records of earliest Triassic plant-bearing deposits *** we report on an Early Triassic flora from Southwest China that provides a rare glimpse into the post-extinction vegetation in the (sub)tropics of Cathavsia.

关键词：生物危机二叠纪三叠纪

On Double Vector Bundles

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Acta Mathematica Sinica,English Series 2014年第10期30卷 1655-1673页

作者： zhuo CHEN Zhang Ju LIU yun He SHENG Department of Mathematics Tsinghua University Department of Mathematics and LMAM Peking University Department of Mathematics Jilin University

In this paper, we construct a category of short exact sequences of vector bundles and prove that it is equivalent to the category of double vector bundles. Moreover, operations on double vector bundles can be transferred to operations on the corresponding short exact sequences. In particular, we study the duality theory of double vector bundles in term of the corresponding short exact sequences. Examples including the jet bundle and the Atiyah algebroid are discussed.

关键词： Double vector bundles DVB sequences duality jet bundles

Reliability Modeling and Maintenance Policy Optimization for Deteriorating System Under Random Shock

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Journal of Shanghai Jiaotong university(Science) 2018年第6期23卷 791-797页

作者： lv yi ZHANG yun School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Computer Engineering University of Electronic Science and Technology of ChinaZhongshan Institute Zhongshan 528400GuangdongChina

Performance degradation and random shock are commonly regarded as two dependent competing risks for system failures. One method based on effective service age is proposed to jointly model the cumulative effect of random shock and system degradation, and the reliability model of degradation system under Nonhomogeneous Poisson processes(NHPP) shocks is derived. Under the assumption that preventive maintenance(PM) is imperfective and the corrective maintenance(CM) is minimal repair, one maintenance policy which combines PM and CM is presented. Moreover, the two decision variables, PM interval and the number of PMs before replacement,are determined by a multi-objective maintenance optimization method which simultaneously maximizes the system availability and minimizes the system long-run expect cost rate. Finally, the performance of the proposed maintenance optimization policy is demonstrated via a numerical example.

关键词： degradation random shock Nonhomogeneous Poisson processes(NHPP) imperfect preventive maintenance multi-objective optimization