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Soil Geochemistry Changes Induced by a Foreign Soil Reconstruction Project in Three Gorges Reservoir Region of China

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Journal of Mountain Science 2015年第6期12卷 1511-1520页

作者： liu juan WEI Chao-Fu LUO You-jin DU jing College of Resources and Environment Southwest University Chongqing Academy of Agricultural Sciences

Fertile topsoil was added onto the surface of barren slope land in Three Gorges Reservoir region of China in an anthropogenic process known as the foreign soil reconstruction project. The main goal of this paper was to reveal the influence of anthropogenic activities on pedogenic processes and soil classifications. Chemical weathering indices and comparative analysis were applied to discuss changes in geochemical compositions and weathering features of purplish soils(Cambisols) before and after the project. Results showed that:(1) The foreign soil reconstruction project slightly altered the major element composition of topsoil and improved the soil structure. Although the distributions of major elements in the original topsoil, original subsoil, foreign topsoil and newly constructed topsoil were all similar to that in upper continental crust, newly constructed topsoil was the most similar soil.(2) The chemical index of alteration was more sensitive than the weathering index of Parker at indicating chemical weathering status of purplish soil. The chemical weathering status of newly constructed topsoil was higher than that of the original topsoil and lower than that of foreign topsoil.(3) Anthropogenic activities may provide a promising new thought for the anthropogenic soil classification system. The scope and subgroups of Anthrosols should be extended and strengthened. Or there may be a need to combine Anthrosols and Technosols orders to create a new soil order. The results may be used for optimizing soil mellowing engineering activities and enriching the soil classification system.

关键词： Anthropogenic activities Weathering status Foreign soil reconstruction project Pedogenic processes Three Gorges Reservoir region China

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Finite element modelling on microstructure evolution during multi-pass hot compression for AZ31 alloys using incremental method

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Journal of Materials Science & Technology 2017年第11期33卷 1255-1262页

作者： Zhaoyang jin Kai Yin Kai Yan Defeng Wu juan liu Zhenshan Cui School of Mechanical Engineering Yangzhou University Yangzhou 225127 China School of Chemistry & Chemical Engineering Yangzhou University Yangzhou 225127 China Nationai Die and Mold CAD Engineering Research Center Shanghaifiao Tong University Shanghai 200030 China

Based on the principle of piecewise linearization, the incremental forms of microstructure evolution models were integrated into the thermo-mechanical coupled finite element（FE） model to simulate nonlinear microstructure evolution during multi-pass hot deformation. This is an unsteady-state deformation where dynamic recrystallization（DRX）, meta-dynamic recrystallization（MDRX）, static recrystallization（SRX） and grain growth（GG） take place during hot deformation or deformation interval. The distributions of deformation and microstructure for cylindrical AZ31 sample during single-pass and double-pass hot compressions were quantitatively calculated and compared with the metallographic observation. It is shown that both the deformation and microstructure are non-uniformly distributed due to the presence of friction between the die and the flat end of sample. The average grain size and its standard deviation under the double-pass hot compression are slightly smaller than those under single-pass *** simulated average grain sizes agree well with the experiments, which validates that the developed FE model on the basis of incremental forms of microstructure evolution models is reasonable.

关键词： Incremental method Microstructure evolution Multi-pass hot compression Finite element method Magnesium alloys

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Logistic Weighted Profile-Based Bi-Random Walk for Exploring MiRNA-Disease Associations

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Journal of Computer Science & Technology 2021年第2期36卷 276-287页

作者： Ling-Yun Dai jin-Xing liu Rong Zhu juan Wang Sha-Sha Yuan School of Computer Science Qufu Normal UniversityRizhao 276826China

MicroRNAs(miRNAs)exert an enormous influence on cell differentiation,biological development and the onset of *** predicting potential miRNA-disease associations(MDAs)by biological experiments usually requires considerable time and money,a growing number of researchers are working on developing computational methods to predict *** accuracy is critical for *** date,many algorithms have been proposed to infer novel ***,they may still have some *** this paper,a logistic weighted profile-based bi-random walk method(LWBRW)is designed to infer potential MDAs based on known *** this method,three networks(i.e.,a miRNA functional similarity network,a disease semantic similarity network and a known MDA network)are constructed *** the process of building the miRNA network and the disease network,Gaussian interaction profile(GIP)kernel is computed to increase the kernel similarities,and the logistic function is used to extract valuable information and protect known ***,the known MDA matrix is preprocessed by the weighted K-nearest known neighbours(WKNKN)method to reduce the number of false ***,the LWBRW method is applied to infer novel MDAs by bi-randomly walking on the miRNA network and the disease ***,the predictive ability of the LWBRW method is confirmed by the average AUC of 0.9393(0.0061)in 5-fold cross-validation(CV)and the AUC value of 0.9763 in leave-one-out cross-validation(LOOCV).In addition,case studies also show the outstanding ability of the LWBRW method to explore potential MDAs.

关键词： miRNA-disease association logistic function Gaussian interaction profile weighted K-nearest known neighbour bi-random walk

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Acyclic Choosability of Graphs with Bounded Degree

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Acta Mathematica Sinica,English Series 2022年第3期38卷 560-570页

作者： juan WANG Lian Ying MIAO jin Bo LI Yun Long liu School of Management Qufu Normal UniversityRizhao276826P.R.China School of Mathematics China University of Mining and TechnologyXuzhou221116P.R.China College of Engineering Qufu Normal UniversityRizhao276826P.R.China

An acyclic colouring of a graph G is a proper vertex colouring such that every cycle uses at least three colours. For a list assignment L = {L(v)| v∈V(G)}, if there exists an acyclic colouringρ such that ρ(v)∈L(v) for each v∈V(G), then ρ is called an acyclic L-list colouring of G. If there exists an acyclic L-list colouring of G for any L with |L(v)|≥k for each v∈V(G), then G is called acyclically k-choosable. In this paper, we prove that every graph with maximum degree Δ≤7 is acyclically 13-choosable. This upper bound is first proposed. We also make a more compact proof of the result that every graph with maximum degree Δ≤3(resp., Δ≤4) is acyclically 4-choosable(resp., 5-choosable).

关键词： Acyclic choosability list colouring acyclic colouring maximum degree

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Control of different occurrence types of organic matter on hydrocarbon generation in mudstones

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Petroleum Science 2022年第4期19卷 1483-1493页

作者： Peng-Yan Du jin-Gong Cai Qing liu Xue-Jun Zhang juan Wang State Key Laboratory of Marine Geology Tongji UniversityShanghai200092China Exploration and Development Research Institute of Shengli Oilfield Company SINOPECDongyingShandong 257001China

Organic matter(OM) is preserved as different occurrences in mudstones, which can affect the hydrocarbon generation process. However, little research has focused on hydrocarbon generation as a function of different occurrences of OM. This study collected a suite of mudstones in the Dongying Sag, Bohai Bay Basin, and conducted Rock-Eval Ⅵ pyrolysis after Soxhlet extraction and Na_(2)S_(2)O_(8) oxidation, aiming to quantify the OM with different occurrences and figure out the contributions of each occurrence of OM to the hydrocarbon generation. There are three types of occurrences of OM: soluble organic matter(SOM),mineral-bound organic matter(MOM), and particulate organic matter(POM). MOM is the most abundant among the three occurrence types of OM. SOM and MOM are the main hydrocarbon precursors, and their hydrocarbon contributions alternate with different kerogen types and layers. Additionally, MOMcontributed hydrocarbons are numerous at shallow depths;SOM-contributed hydrocarbons mainly occur at deep depths;and POM-contributed hydrocarbons change little with depth. These results demonstrate that MOM should be the main hydrocarbon precursor in shallow formations and that SOM is the main hydrocarbon contributor at deep depths.

关键词： Soluble organic matter Mineral-bound organic matter Particulate organic matter Hydrocarbon precursor Rock-EvalⅥpyrolysis

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Recent Progress on 2D Transition Metal Compounds-based Electrocatalysts for Efficient Nitrogen Reduction

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Chemical Research in Chinese Universities 2020年第4期36卷 648-661页

作者： DONG Wcnfei CHEN Xiaoyu PENG juan liu Wanyi jin Xiaoyong NI Gang liu Zheng State Key Laboratoty of High-efficiency Utilization of Coal and Green Chemical Engineering National Demonstration Center for Experimental Chemistry EducationCollege of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021P.R.China School of Materials Science and Engineeting Nanyang Technological UniversitySingapore 639798Singapore CINTRA CNRS NTU THALES Research Techno PlazaSingapore 639798Singapore Environmental Chemistry and Materials Centre Nanyang Environment and Water Research InstituteSingapore 639798Singapore

Ammonia is a commodity chemical with high added *** reduction of nitrogen has great promise for the sustainable synthesis of ammonia in recent *** of its rich resources and unique electronic structure and characteristics,2D transition metal compounds have been used as electrocatalysts for electro-chemical reduction of nitrogen for clean and sustainable production of ammonia,This review outlines the latest development in the use of 2D transition metal compounds as high-efficiency electrocatalysts for nitrogen ***(NRR).First,we introduce the N,reduction mechanism,and briefly summarize the performance indicators ofthe ***,we focused on the functionalization of unique 2D materials to design high-performance 2D electrocatalysts in respect of simulation calculation and experimental ***,the current challenges and future opportunities for NRR electrocatalvsts are introduced.

关键词： Electrochemical NH3 svnthesis Transition metal Nitrogen fixation Electrocatalysis

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Characterization of a Novel Rice Metallothionein Gene Promoter:Its Tissue Specificity and Heavy Metal Responsiveness

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Journal of Integrative Plant Biology 2010年第10期52卷 914-924页

作者： Chun-juan Dong Yun Wang Shi-Shi Yu jin-Yuan liu Laboratory of Molecular Biology and MOE Laboratory of Protein Science School of Life Sciences Tsinghua University Beijing 100084China

The rice （Oryza sativa L.） metallothionein gene OsMT-I-4b has previously been identified as a type I MT gene. To elucidate the regulatory mechanism involved in its tissue specificity and abiotic induction, we isolated a 1 730 bp fragment of the OsMT-I-4b promoter region. Histochemical /^-glucuronidase （GUS） staining indicated a precise spacial and temporal expression pattern in transgenic Arabidopsis. Higher GUS activity was detected in the roots and the buds of flower stigmas, and relatively lower GUS staining in the shoots was restricted to the trichomes and hydathodes of leaves. No activity was observed in the stems and seeds. Additionally, in the root of transgenic plants, the promoter activity was highly upregulated by various environmental signals, such as abscisic acid, drought, dark, and heavy metals including Cu2＋, Zn2~, Pb2~ and Al3＋. Slight induction was observed in transgenic seedlings under salinity stress, or when treated with Co2＋ and Cd2＋. Promoter analysis of 5＇-deletions revealed that the region -583/-1 was sufficient to drive strong GUS expression in the roots but not in the shoots. Furthermore, deletion analysis indicated important promoter regions containing different metal- responsive c/s-elements that were responsible for responding to different heavy metals. Collectively, these findings provided important insight into the transcriptional regulation mechanisms of the OsMT-I- 4b promoter, and the results also gave us some implications for the potential application of this promoter in plant genetic engineering.

关键词： PLANT gene expression PLANT genetics METALLOTHIONEIN PROMOTERS (Genetics) HEAVY metals PLANT genetic engineering TRANSGENIC rice ARABIDOPSIS PLANT cells & tissues GENETIC regulation in plants

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Size-dependent thermomechanical vibration characteristics of rotating pre-twisted functionally graded shear deformable microbeams

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1015-1032页

作者： Songye jin Bo ZHANG Wuyuan ZHANG Yuxing WANG Huoming SHEN jing WANG juan liu School of Mechanics and Aerospace Engineering Southwest Jiaotong UniversityChengdu 610031China School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China School of Mechanical and Electrical Engineering Southwest Petroleum UniversityChengdu 610500China

A three-dimensional(3D)thermomechanical vibration model is developed for rotating pre-twisted functionally graded(FG)microbeams according to the refined shear deformation theory(RSDT)and the modified couple stress theory(MCST).The material properties are assumed to follow a power-law distribution along the chordwise *** model introduces one axial stretching variable and four transverse deflection variables including two pure bending components and two pure shear *** complex modal analysis and assumed mode methods are used to solve the governing equations of motion under different boundary conditions(BCs).Several examples are presented to verify the effectiveness of the developed *** coupling the slenderness ratio,gradient index,rotation speed,and size effect with the pre-twisted angle,the effects of these factors on the thermomechanical vibration of the microbeam with different BCs are *** is found that with the increase in the pre-twisted angle,the critical slenderness ratio and gradient index corresponding to the thermal instability of the microbeam increase,while the critical material length scale parameter(MLSP)and rotation speed *** sensitivity of the fundamental frequency to temperature increases with the increasing slenderness ratio and gradient index,and decreases with the other increasing ***,the size effect can suppress the dynamic stiffening effect and enhance the Coriolis ***,the mode transition is quantitatively demonstrated by a modal assurance criterion(MAC).

关键词： thermomechanical vibration rotating pre-twisted functionally graded(FG)microbeam refined shear deformation theory(RSDT) modified couple stress theory(MCST) modal assurance criterion(MAC)

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Temperature-regulated self-assembly of lipids at free bubbles interface:A green and simple method to prepare micro/nano bubbles

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Nano Research 2020年第4期13卷 999-1007页

作者： juan jin Fang Yang Bin Li Dong liu Lihong Wu Yan Li Ning Gu State Key Laboratory of Bioelectronics Jiangsu Key Laboratory for Biomaterials and DevicesSchool of Biological Sciences and Medical EngineeringSoutheast UniversityNanjing 210096China West Anhui University Luan 237012China Anhui Engineering Laboratory for Conservation and Sustainable Utilization of Traditional Chinese Medicine Resources Luan 237012China CSPC Zhongqi Pharmaceutical Technology(SJZ)Co. Ltd.Shijiazhuang 050035China

Micro/nanobubbles play an essential role in ultrasound-based biomedical ***,a green and simple method to fabricate micro/nanobubbles was developed by the temperature-regulated self-assembly of lipids in the presence of free *** self-assembly mechanism of lipids interacting with gas-water interfaces was investigated,and the ultrasound imaging of the obtained lipid-encapsulated bubbles(LBs)was further *** the phase transition temperature(Tm),fluid lipids transform from vesicles to micelles,and further assemble to the free bubbles interface to be a compressed monolayer,resulting in lipid shelled *** below 7m induces the lipid shell to glassy state and stables the ***,increasing the 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000](DSPE-PEG2K)content in lipids formulation can further manipulate the shell curvature and reduce the LBs size into *** with diameters of 1.68±0.11 pm,704±7 nm and 208±6 nm were successfully *** in vitro and in vivo ultrasound imaging results showed that all of the LBs had excellent *** nanosized LBs revealed elongated imaging duration time and greater microvascular details for the liver *** the organic solvent and complicated multiple preparation process,this method has great potential in construction of various multifunctional micro/nanobubbles with size control for theranostic applications.

关键词： lipid self-assembly gas-liquid interface microbubbles nanobubbles ultrasound imaging

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VEGF、PEDF在寻常型银屑病组织中的表达及与微血管密度的关系

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皮肤病与性病 2019年第3期41卷 318-320页

作者：陈艳明李勇坚刘金娟石小桥南华大学附属第二医院皮肤性病科湖南衡阳421001 南华大学附属第二医院麻醉科湖南衡阳421001

目的探讨VEGF、PEDF蛋白在寻常型银屑病组织中的表达及与真皮浅层微血管密度(MVD)的关系,从而阐述寻常型银屑病的发病机制。方法应用免疫组织化学方法(PV-9000)检测皮肤组织中VEGF、PEDF蛋白的表达水平,CD31蛋白标记微血管计算真皮浅... 详细信息

目的探讨VEGF、PEDF蛋白在寻常型银屑病组织中的表达及与真皮浅层微血管密度(MVD)的关系,从而阐述寻常型银屑病的发病机制。方法应用免疫组织化学方法(PV-9000)检测皮肤组织中VEGF、PEDF蛋白的表达水平,CD31蛋白标记微血管计算真皮浅层MVD;采用Spearman法进行相关性分析。结果 VEGF、PEDF蛋白表达水平及真皮浅层MVD值在阳性组中明显高于阴性组和对照组,差异显著有统计学意义(P0.05);相关性分析显示MVD与VEGF的表达水平呈正相关(P<0.001);MVD与PEDF的表达水平呈负相关(P<0.001)。结论 VEGF、PEDF可能通过调节血管增生参与银屑病的发病过程。

关键词：银屑病 PEDF VEGF 微血管密度

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