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华北东部晚古生代过渡相煤系地层低阻成因、控制因素与地质意义

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煤炭科学技术 2024年第3期52卷 159-168页

作者：侯中帅梁钊陈世悦河北省战略性关键矿产资源重点实验室河北石家庄050031 河北地质大学能源研究所河北石家庄050031 中国石油大学(华东)地球科学与技术学院山东青岛266580

华北东部晚古生代过渡相煤系地层中低阻层发育,明确其成因类型、控制因素以及地质意义,可以充分揭示其中所包含的地质信息,对于相关层系油气资源评价和勘探部署具有积极意义。本文以华北东部太原组和山西组中低阻层为研究对象,综合运用... 详细信息

华北东部晚古生代过渡相煤系地层中低阻层发育,明确其成因类型、控制因素以及地质意义,可以充分揭示其中所包含的地质信息,对于相关层系油气资源评价和勘探部署具有积极意义。本文以华北东部太原组和山西组中低阻层为研究对象,综合运用岩心、薄片、扫描电镜、碳氧同位素和测录井资料,围绕其成因类型、控制因素和地质意义开展研究。结果表明:华北东部晚古生代过渡相煤系低阻层主要发育在太1段和山2段,成因类型包括砂泥岩薄互层、高束缚水体积和发育导电矿物,沉积作用和成岩作用控制了低阻的形成;太1段低阻的成因为砂泥岩薄互层和高束缚水体积,潮汐作用导致的潮汐成因层理和微细孔隙发育促进了障壁海岸背景下太1段低阻的形成,山2段低阻的成因为菱铁矿的密集发育,稳定的覆水还原环境和沉积有机物的成岩演化共同控制了三角洲背景下山2段低阻的形成;太1段的低阻和高毛细管束缚水体积指示着潮坪沉积,说明太原组自下而上为一个海退的过程,是对早二叠世早期冈瓦纳冰川迅速扩张和全球海平面快速下降的响应,山2段的低阻和高光电吸收截面指数指示着三角洲前缘沉积,说明山西组由一期三角洲沉积组成。

关键词：砂泥岩薄互层高束缚水体积导电矿物低阻煤系地层

济南南部山区土地利用/覆被变化对碳储量的影响研究

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中国环境科学 2024年第7期44卷 3986-3998页

作者：王怡冰李成亮张鹏侯蕾刘仲秋刘经强邱庆泰赵辰瑞山东农业大学资源与环境学院土肥资源高效利用国家工程实验室山东泰安271018 山东农业大学水利土木工程学院山东泰安271018

以黄河下游生态脆弱区-济南南部山区为研究对象,基于区域1980~2020年6期土地利用/覆被数据,结合InVEST模型(Integrated Valuation of Ecosystem Services and Trade-offs model),分析区域土地利用/覆被和碳储量的时空分布特征和动态变... 详细信息

以黄河下游生态脆弱区-济南南部山区为研究对象,基于区域1980~2020年6期土地利用/覆被数据,结合InVEST模型(Integrated Valuation of Ecosystem Services and Trade-offs model),分析区域土地利用/覆被和碳储量的时空分布特征和动态变化规律,研究土地利用/覆被变化对陆地生态系统碳储量的影响.结果表明,土地利用/覆被变化对碳储量的影响较为显著,1980~2005年土地利用变化较小,人类活动影响较小,由于林草地碳储量的累积,碳储量增长速度明显高于其他时期;2005~2010年城市扩张速度最快,城乡建设用地大量侵占耕地、林地和草地,使区域固碳能力明显下降;2010~2020年,由于城市化扩张限制以及植树造林等生态保护措施的实施,区域碳储量逐渐呈增长趋势;1980~2020年济南南部山区的总碳储量呈“增长-下降-增长”的趋势;并且林地是济南南部山区碳储量的主要供给者,区域碳储量值随着远离城乡居民生活中心的距离增大而增大,说明人类活动对区域碳储量有重要的影响.另外,土地利用类型的转移引起地类碳密度的变化,是区域碳储量变化的主要影响因素,土地利用类型的碳储量变化与各地类的面积变化有一定的关系.该成果可为生态脆弱区塑造良好的陆地碳汇格局提供理论依据.

关键词：济南南部山区土地利用/覆被变化 InVEST模型碳储量的影响

Borophene-ZnO heterostructures:Preparation and application as broadband photonic nonvolatile memory

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Nano Research 2023年第4期16卷 5826-5833页

作者： Runsheng Liu Chuang hou Xinchao Liang zitong Wu Guoan tai The State Key Laboratory of Mechanics and Control of Mechanical Structures and Laboratory of Intelligent Nano Materials and Devices of Ministry of Education College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

High-performance photonic nonvolatile memory which combines data storage and photosensing can achieve low power consumption and ensure computational energy *** has been theoretically and experimentally proved to have synergistic effects between two materials,which can lead to promising electronic and optical properties for advanced optoelectronic ***,we report the preparation of borophene-ZnO heterostructures and their applications of broadband photonic nonvolatile *** memory shows a good switching ratio(5×10^(3))and long-term stability(3,600 s),which are superior to those of the pristine borophene or ZnO quantum dots(QDs).It is found that the memory shows a broad light response from ultraviolet(365 nm)to near infrared(850 nm).Besides,the SET voltage will decrease when the device is exposed to light,which can be attributed to the separation of holes and electrons in accelerating the formation of vacancy conductive *** work not only provides a promising material for next-generation photoelectric information,but also paves the way for borophene-based memory towards data storage devices.

关键词： borophene ZnO heterostructure photoluminescence(PL)quenching nonvolatile memory light control

Borophene–graphene heterostructure: Preparation and ultrasensitive humidity sensing

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Nano Research 2021年第7期14卷 2337-2344页

作者： Chuang hou Guo'an tai Bo Liu Zenghui Wu Yonghe Yin The State Key Laboratory of Mechanics and Control of Mechanical Structures and Laboratory of Intelligent Nano Materials and Devices of Ministry of Education College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Heterostructure has triggered a surge of interest due to its synergistic effects between two different layers,which contributes to desirable physical properties for extensive potential *** stable borophene is becoming a promising candidate for constructing two-dimensional(2D)heterostructures,but it is rarely prepared by suitable synthesis conditions ***,we demonstrate that a novel heterostructure composed of hydrogenated borophene and graphene can be prepared by heating the mixture of sodium borohydride and few-layered graphene followed by stepwise and in situ thermal decomposition of sodium borohydride under high-purity hydrogen as the carrier *** fabricated borophene–graphene heterostructure humidity sensor shows ultrahigh sensitivity,fast response,and long-time *** sensitivity of the fabricated borophene-based sensor is near 700 times higher than that of pristine graphene one at the relative humidity of 85%*** sensitivity of the sensor is highest among all the reported chemiresistive sensors based on 2D ***,the performance of the borophene–graphene flexible sensor maintains good stability after bending,which shows that the borophene-based heterostructures can be applied in wearable *** observed high performance can be ascribed to the well-established charge transfer mechanism upon H2O molecule *** study further promotes the fundamental studies of interfacial effects and interactions between boron-based 2D heterostructures and chemical species.

关键词： borophene graphene heterostructure humidity sensor two-dimensional materials

LC-MS/MS法测定中国孕妇胎盘中地塞米松相关代谢酶和转运体蛋白丰度

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药物分析杂志 2024年第1期44卷 76-88页

作者：李辉郭萱侯哲刘东阳董静杭太俊张雷北京大学第三医院北京100191 中国药科大学南京210009 岛津中国创新中心北京100020

目的:建立LC-MS/MS方法测定中国孕妇胎盘中地塞米松相关代谢酶和转运体的丰度数据。方法:采用Shim-pack GISS-HP C_(18)(100 mm×2.1 mm, 1.9μm)色谱柱,柱前由0.2%甲酸-水(A)和0.2%甲酸-乙腈(B)组成的流动相,以0.2 mL·min^(-1)的流速... 详细信息

目的:建立LC-MS/MS方法测定中国孕妇胎盘中地塞米松相关代谢酶和转运体的丰度数据。方法:采用Shim-pack GISS-HP C_(18)(100 mm×2.1 mm, 1.9μm)色谱柱,柱前由0.2%甲酸-水(A)和0.2%甲酸-乙腈(B)组成的流动相,以0.2 mL·min^(-1)的流速进行梯度洗脱,柱后以0.1 mL·min^(-1)的流速加入0.5%乙二醇-乙腈(流动相C),采用ESI源正离子MRM模式进行定量分析。对所建立的方法进行方法学考察并对中国孕妇孕晚期胎盘中11β羟基类固醇脱氢酶1(11β-HSD1)、11β羟基类固醇脱氢酶2(11β-HSD2)、细胞色素P450 3A4酶(CYP3A4)和P-糖蛋白(P-gp)蛋白表达量进行定量分析。结果:建立的LC-MS/MS分析测定方法的线性范围为0.1~100 nmol·L^(-1)(r>0.999);精密度和准确度结果均符合《中华人民共和国药典》对于生物样品分析方法学验证的要求(RSD≤15%),稳定性结果显示样品稳定性良好。11β-HSD2、11β-HSD1、CYP3A4和P-gp的蛋白丰度分别为(84.46±59.97) pmol·g^(-1)、(11.44±3.73) pmol·g^(-1)、(8.83±2.78) pmol·g^(-1)和(7.94±4.10) pmol·g^(-1)。同时研究结果显示相关代谢酶和转运体在胎盘不同部位的分布没有显著差异,但中国人胎盘P-gp的丰度(7.94±4.10) pmol·g^(-1)和白人(4.41±2.46) pmol·g^(-1)相比存在显著性差异。结论:本研究建立的LC-MS/MS方法准确度和灵敏度高,适用于检测人类胎盘中地塞米松相关代谢酶和转运体的丰度值。

关键词：液相色谱-二级质谱联用细胞色素P4503A4酶 P-糖蛋白 11β羟基类固醇脱氢酶蛋白丰度孕妇胎盘地塞米松

Instability of OTSG in movable NPP by using multivariable frequency domain method

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Nuclear Science and Techniques 2010年第1期21卷 54-59页

作者： hou Suxia tai Yun ZHAO Fuyu WEI Xinyu Xi ＇an Jiaotong University Xi ＇an 710049 China The Second Artillery Engineering Institute Xi ＇an 710025 China

The instability occurring in OTSG (Once-Through Steam Generator) of movable nuclear power plants is presented by a multivariable frequency domain *** concerning coupling interactions of OTSG tubing,it is more efficient for analyzing the instability of OTSG compared the common single variable method.A mathematical model for the system is derived from the fundamental equations by using the perturbation,Laplace-transform and the nodalization *** stable boundary and parameters which influence the stability of the system are evaluated through computer *** examples are given in the paper and the predictions of the model agree with the experimental results well.

关键词：直流蒸汽发生器多变量频域法不稳定核电站拉普拉斯变换数学模型计算机模拟耦合作用

Crystal and Molecular Structure of 2,3,5,6-Bis(ortho-1,10-decylidene)dihydropyrazine

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1254-1258页

作者： WANG Ming-An ZHANG Ning hou Xue-tai WANG Dao-Quan Department of Applied Chemistry China Agricultural University Beijing 100094 China

The SnCl2 reduction of 2-nitrocyclododecanone or 2-bromo-12-nitrocyclododecanone gave a colorless compound 2,3,5,6-bis（ortho-1,10-decylidene）dihydropyrazine 1a characterized by IR, NMR and X-ray diffraction analysis. Crystal data for 1a： Mr = 358.60, monoclinic, space group P2 1/n, α = 0.48028（3）, b = 2.8646（4）, c = 0.77097（6） nm, β = 98.432（12）°, V = 1.04924（19） nm^3, Dc = 1.135 g/cm^3, Z = 2, F（000） = 400 and μ（MoKa） = 0.065 mm^-1. All ^1H- and ^13C-NMR resonance lines of 1a were assigned by DEPT, COSY, HMQC and HMBC technology. In the crystal, the dihydropyrazine ring has a planar structure, two twelve-membered tings adopt [lene2333] conformation, their double bonds have cis-configuration, and the whole molecule has a center of symmetry. In solution, the symmetric ^1H- and ^13C-NMR signals suggest that two twelve-membered rings of 1a may adopt enantiomorphous [ lene2333] conformation existing in a dynamic equilibrium.

关键词： 2,3,5,6-bis(ortho-1,10-decylidene)dihydropyrazine crystal structure NMR

Transcriptome datasets supply basic gene information for RNAi pest management and gene functional studies in Nephotettix cincticeps(Uhler)

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Journal of Integrative Agriculture 2016年第4期15卷 840-847页

作者： CHEN tai-yu hou Ji-xiang LIN Yong-jun National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University College of Plant Science & Technology Huazhong Agricultural University

RNA interference （RNAi） technology has the potential to be used in pest management in crop production. Here, the transcriptome of Nephotettix cincticeps （Uhler） was deeply sequenced to investigate the systematic RNAi mechanism and candidate genes for dsRNA feeding. In our datasets, a total of 81 225 transcripts were obtained with the length from 150 bp to about 4.2 kb. Almost all the genes related to the RNAi core pathway were proved to be present in N. cincticeps transcriptome. Two transcripts that respectively encode a systemic interference defective （SID） were identified in our da- tabase, indicating that the systematic RNAi pathway can function effectively in N. cincticeps. Our datasets not only supply basic gene information for the studies of gene expression and functions in N. cincticeps, such as the control genes for gene expression analysis, but also provide candidate genes for RNAi pest management, such as the genes that encode P450 monooxygenase, V-ATPase and chitin synthase.

关键词： Nephotettix cincticeps transcriptome RNA interference house-keeping genes

SpinNet: Spinning convolutional network for lane boundary detection

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Computational Visual Media 2019年第4期5卷 417-428页

作者： Ruochen Fan Xuanrun Wang Qibin hou Hanchao Liu tai-Jiang Mu Tsinghua University Beijing100084China Nankai University Tianjin300350China

In this paper,we propose a simple but effective framework for lane boundary detection,called Spin *** that cars or pedestrians often occlude lane boundaries and that the local features of lane boundaries are not distinctive,therefore,analyzing and collecting global context information is crucial for lane boundary *** this end,we design a novel spinning convolution layer and a brand-new lane parameterization branch in our network to detect lane boundaries from a global *** extract features in narrow strip-shaped fields,we adopt stripshaped convolutions with kernels which have 1×n or n×1 shape in the spinning convolution *** tackle the problem of that straight strip-shaped convolutions are only able to extract features in vertical or horizontal directions,we introduce the concept of feature map rotation to allow the convolutions to be applied in multiple directions so that more information can be collected concerning a whole lane ***,unlike most existing lane boundary detectors,which extract lane boundaries from segmentation masks,our lane boundary parameterization branch predicts a curve expression for the lane boundary for each pixel in the output feature *** the network utilizes this information to predict the weights of the curve,to better form the final lane *** framework is easy to implement and end-to-end *** show that our proposed Spin Net outperforms state-of-the-art methods.

关键词： object detection lane boundary detection autonomous driving deep learning