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城固县核桃丰产优质栽培技术要点

南方农业 2024年第5期18卷 121-124页

作者：张康张春刘小平城固县木材检查站陕西城固723200 城固县秦巴生态保护中心陕西城固723200

核桃是陕西省城固县的名优特产之一,对推动当地农业经济发展和农民致富增收具有重要作用。核桃栽植时,其成活率、产量、质量和栽植技术密切相关。为保证核桃成活率、提高核桃产量与品质,以城固县为例,从科学建园、合理选种、育苗、定植... 详细信息

核桃是陕西省城固县的名优特产之一,对推动当地农业经济发展和农民致富增收具有重要作用。核桃栽植时,其成活率、产量、质量和栽植技术密切相关。为保证核桃成活率、提高核桃产量与品质,以城固县为例,从科学建园、合理选种、育苗、定植造林、幼林抚育、成林管理等方面对核桃优质栽培技术措施展开探析。

关键词：核桃栽培技术陕西省城固县

燕辽裂陷槽基底陆壳生长事件——来自长城系碎屑锆石U-Pb年龄和Lu—Hf同位素的启示

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地质论评 2024年第4期70卷 1335-1352页

作者：李文奇刘汇川刘小平于志琪王艺壬王莹莹油气资源与探测国家重点实验室中国石油大学(北京)北京102249 中国石油大学(北京)地球科学学院北京102249

华北克拉通大陆地壳生长已有大量研究,但对于被巨厚沉积盖层覆盖的燕辽裂陷槽基底地壳生长的问题前人讨论较少。笔者等以燕辽裂陷槽基底之上的长城系沉积岩为研究对象,统计了燕辽裂陷槽内长城系地层中碎屑锆石年龄频谱和Lu—Hf同位素数... 详细信息

华北克拉通大陆地壳生长已有大量研究,但对于被巨厚沉积盖层覆盖的燕辽裂陷槽基底地壳生长的问题前人讨论较少。笔者等以燕辽裂陷槽基底之上的长城系沉积岩为研究对象,统计了燕辽裂陷槽内长城系地层中碎屑锆石年龄频谱和Lu—Hf同位素数据,探讨长城系地层沉积年龄、碎屑锆石沉积源区和地壳生长事件等科学问题。同位素年龄将燕辽裂陷槽长城系沉积年龄约束为1680 Ma,代表着燕辽裂陷槽的开启时间。燕辽裂陷槽长城系碎屑锆石年龄频谱主要显示为2.7~2.5 Ga和2.2~1.9 Ga两个阶段,Hf同位素ε_(Hf)(t)表现为高的正值区间0.1~34.6。通过对比长城系碎屑锆石与华北克拉通结晶基底的U-Pb定年、Lu—Hf同位素ε_(Hf)(t)和T_(DM2)模式年龄数据,推测燕辽裂陷槽长城系沉积物源为燕辽裂陷槽下伏基底。结合碎屑锆石U-Pb定年、ε_(Hf)(t)值和T_(DM2)模式年龄数据,我们认为燕辽裂陷槽下伏基底中元古代前地壳生长有3个峰值,分别为2.7~2.5 Ga,2.2~1.9 Ga和1.7~1.6 Ga。

关键词：燕辽裂陷槽长城系长城群碎屑锆石 U-Pb年龄 Lu—Hf同位素陆壳生长

Exploration Strategies for Complex Fault Block Reservoirs in the Subei Basin

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Petroleum Science 2007年第1期4卷 30-35页

作者： liu xiaoping Yang Xiaolan liu Yurui Basin and Reservoir Research Center China University of Petroleum Beijng 102249 China Key Laboratory for Hydrocarbon Accumulation Mechanism under Ministry of Education China University of Petroleum Beijing 102249 China China University of Geosciences Beijing 10083 China Jiangsu Oilfield Branch Company SINOPEC Yangzhou Jiangsu 225009 China

The geological background of the Subei basin is that of small relief subsidence, low geothermal gradient, multi-sedimentary hiatuses, intense reconstruction of the basin, frequent magmatic activity, and a unique combination of source rock and reservoir. This geological background resulted in characteristics such as many small fault blocks, multiple oil-bearing formations, scattered oil distribution, mini- to small-sized reservoirs, and difficulties in exploration. Aimed at such characteristics, an effective exploration strategy was adopted, and the oil reserves, production and economic benefits of the Jiangsu oilfield were significantly increased. This exploration strategy included understanding the hydrocarbon generation mechanism of source rocks, progressive evaluation of oil resources, comprehensive research on the faulted systems, the distribution of oil reservoirs and their controlling factors. The techniques used included integration of acquisition, processing and interpretation with 3-D seismics as the core technology, trap description and evaluation, directional drilling and cluster drilling, integration of cuttings logging, gas chromatographic logging and geochemical logging, and integration of early reservoir description and progressive exploration and development. This strategy could be guidance for other complex fault blocks.

关键词： Complex fault block petroleum exploration technical strategy Subei Basin

数字经济对黄河流域生态保护的影响研究——基于产业结构升级的视角

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中国商论 2024年第11期 146-150页

作者：李世寒刘晓平青海大学财经学院青海西宁810000

作为一种新兴经济形态,数字经济对实现生态保护具有重要意义。本文以产业结构升级为视角,通过选取2011—2021年黄河流域九个省(自治区)的面板数据,利用环境影响随机模型以及中介效应模型,构建了基于状态-压力-响应(PSR)逻辑的生态保护... 详细信息

作为一种新兴经济形态,数字经济对实现生态保护具有重要意义。本文以产业结构升级为视角,通过选取2011—2021年黄河流域九个省(自治区)的面板数据,利用环境影响随机模型以及中介效应模型,构建了基于状态-压力-响应(PSR)逻辑的生态保护水平指标体系并采用熵值法计算出黄河流域各省(区)的生态保护水平和数字经济发展水平,最后采用固定效应回归模型进行检验分析。研究发现:数字经济对黄河流域的生态保护具有显著的促进作用;产业结构是数字经济作用于生态保护的重要路径;黄河流域内数字经济对生态保护释放的红利程度在空间上呈现出“中游>下游>上游”的特点,呈现异质性特征。基于此,本文建议加强对数字经济理论研究,提升数字经济在传统产业的应用,促进产业结构优化升级,对实现黄河流域高质量发展至关重要。

关键词：产业结构升级生态保护数字经济黄河流域区域经济新兴经济

Integration of small world networks with multi-agent systems for simulating epidemic spatiotemporal transmission

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Chinese Science Bulletin 2010年第13期55卷 1285-1293页

作者： liu Tao LI Xia liu xiaoping School of Geography and Planning Sun Yat-sen University Guangzhou 510275 China

This study proposes an integrated model based on small world network (SWN) and multi-agent system (MAS) for simulating epidemic spatiotemporal transmission. In this model, MAS represents the process of spatiotemporal interactions among individuals, and SWN describes the social relation network among agents. The model is composed of agent attribute definitions, agent movement rules, neighborhoods, construction of social relation network among agents and state transition rules. The construction of social relation network and agent state transition rules is essential for implementing the proposed model. The decay effects of infection "memory", distance and social relation between agents are introduced into the model, which are unavailable in traditional models. The proposed model is used to simulate the transmission process of flu in Guangzhou City based on the swarm software platform. The integration model has better performance than the traditional SEIR model and the pure MAS based epidemic model. This model has been applied to the simulation of the transmission of epidemics in real geographical environment. The simulation can provide useful information for the understanding, prediction and control of the transmission of epidemics.

关键词：小世界网络传播模拟疫情传播网络传输多代理时空统集成综合模型

Neural Network-Based Adaptive Motion Control for a Mobile Robot with Unknown Longitudinal Slipping

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Chinese Journal of Mechanical Engineering 2019年第4期32卷 26-34页

作者： Gang Wang xiaoping liu Yunlong Zhao Song Han Automation School Beijing University of Posts and Telecommunications

When the mobile robot performs certain motion tasks in complex environment, wheel slipping inevitably occurs due to the wet or icy road and other reasons, thus directly influences the motion control accuracy. To address unknown wheel longitudinal slipping problem for mobile robot, a RBF neural network approach based on whole model approximation is presented. The real-time data acquisition of inertial measure unit(IMU), encoders and other sensors is employed to get the mobile robot’s position and orientation in the movement, which is applied to compensate the unknown bounds of the longitudinal slipping using the adaptive technique. Both the simulation and experimental results prove that the control scheme possesses good practical performance and realize the motion control with unknown longitudinal slipping.

关键词： Mobile robot Longitudinal slipping RBF neural network Adaptive control

Preparation and characteristics of indium tin oxide (ITO) thin films at low temperature by r.f. magnetron sputtering

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Rare Metals 2006年第z1期25卷 137-140页

作者： REN Bingyan liu xiaoping WANG Minhua XU Ying School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China Beijing Solar Energy Research Institute Beijing 100083 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China

Low resistivity and highly transparent ITO conducting films for solar cell applications were fabricated at low temperature by r.f. magnetron sputtering. ITO films were deposited on glass and silicon substrate. Electrical, optical, structural and morphological properties of the ITO films were investigated in terms of the preparation conditions. The annealing treatment has improved the properties of the ITO films at different degree. The maximum transmittance of the obtained ITO films in the visible range is over 92%, and the low resistivity for the ITO films are about 3.85×10-4 Ω·cm at 80 ℃, 80 W after annealing.

关键词： ITO r.f. magnetron sputtering low temperature annealing

Oxidation behavior of niobized TiAl by plasma surface alloying

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Journal of University of Science and Technology Beijing 2008年第5期15卷 590-593页

作者： Dongdong Chen Wenhuai Tian Jian Wang xiaoping liu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Research Institute of Surface Engineering Taiyuan University of Technology Taiyuan 030024 China

Plasma surface alloying of element Nb in TiAl-based alloys and the oxidation behavior were studied. The composition and microstructure of the surface alloyed layers were investigated by means of scanning electron microscopy （SEM）,energy dispersive X-ray analysis （EDX）,and X-ray diffraction （XRD）. The experimental results indicate that the diffusion layers are formed on the TiAl substrate during the plasma niobizing process. The result from oxidation resistance investigation shows that plasma niobizing greatly improves the oxidation resistance of TiAl compared with the untreated TiAl. The role of element Nb for improving the oxidation resistance is considered to be achieved by strengthening the activity of Al,which is induced by the plasma niobizing process.

关键词： TiAl alloys plasma niobizing oxidation resistance surface alloying

Effect of H treatment on performance of HIT solar cells

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Rare Metals 2006年第z1期25卷 133-136页

作者： REN Bingyan WANG Minhua liu xiaoping XU Ying School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China Beijing Solar Energy Research Institute Beijing 100083 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China

Hydrogen is a ubiquitous element in semiconductor processing and particularly in amorphous and microcrystalline silicon where it plays a crucial role in the growth processes as well as in the material properties. Because of its low mass it can easily diffuse through the silicon network and leads to the passivation of dangling bonds but it may also play a role in the stabilization of metastable defects. Thus a lot of work has been devoted to the study of hydrogen diffusion, bonding and structure in disordered semiconductors. The sequence, deposition-exposure to H plasma-deposition was used to fabricate the microcrystalline emitter. A proper atomic H pretreatment of c-Si surface before depositions i layer was expected to clean the surface and passivatates the surface states, as a result improing the device parameters. In this study, H2 pretreatment of c-si surface was used at different time, power and temperature. It is found that a proper H pretreatment improves passivation of c-si surface and improves the device parameters by AFM and testing I-V.

关键词： H pretreatment HIT solar cell c-si buffer layer