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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China

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Chinese Geographical Science 2024年第2期34卷 342-356页

作者： shi xiaoliang CHEN Jiajun DING Hao YANG Yuanqi ZHANG Yan College of Geomatics Xi’an University of Science and TechnologyXi’an 710054China

Precise and timely prediction of crop yields is crucial for food security and the development of agricultural ***,crop yield is influenced by multiple factors within complex growth *** research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter ***,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly *** study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat *** the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was *** estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)***,the determined optimal yield estimation method was used to predict winter wheat yield in three typical *** are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other *** best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe *** with severe drought year(201

关键词： winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time Henan Province,China

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Properties, Phases and Microstructure of Microwave Sintered W-20Cu Composites from Spray Pyrolysis-continuous Reduction Processed Powders

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 38-44页

作者： TAO Jianqin shi xiaoliang State Key Laboratory of Advanced Technology for Materials Synthesis&Processing Wuhan University of TechnologyWuhan 430070 China School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan 430070China

The effects of microwave sintering on the properties, phases and microstructure of W-2OCu alloy, using composite powder fabricated by spray pyrolysis-continuous reduction technology, were investigated. Compared with the conventional hot-press sintering, microwave sintering to W-2OCu composites could be achieved with lower sintering temperature and shorter sintering time. Furthermore, microwave sintered W-Cu composites with high densification, homogenous microstructure and excellent properties were obtained. Microwave sintering could also result in finer microstructures. ：~

关键词： W-2OCu composite powder spray pyrolysis-continuous reduction microwave sintefing

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A Method for Spatial Heterogeneity Evaluation on Landscape Pattern of Farmland Shelterbelt Networks:A Case Study in Midwest of Jilin Province,China

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Chinese Geographical Science 2011年第1期21卷 48-56页

作者： shi xiaoliang LI Ying DENG Rongxin Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduated University of Chinese Academy of Sciences Beijing 100049 China

On the basis of landscape ecology, combining the Spot 5 high resolution satellite imagery with GIS, a method evaluating the spatial heterogeneity of shelterbelts distribution at landscape scale is put forward in this paper. The distance coefficients of reasonable and existing landscape indexes of farmland shelterbelt networks were com-puted, and then through the classification of the distance coefficients, and the establishment of evaluation rules, the spatial heterogeneity of farmland shelterbelts was evaluated. The method can improve the evaluating system of previ-ous studies on shelterbelts distribution, resolve the disadvantages of lacking spatiality of overall evaluation, and make the evaluation results have more directive significance for shelterbelt management. Based on this method, spatial het-erogeneity of shelterbelt networks was evaluated in the midwest of Jilin Province, China. The results show that the re-gions with fewer shelterbelts and no closed network account for 34.7% of the total area, but only 4.9% of the area has relative reasonable pattern of shelterbelt networks. Many problems exist in the distribution pattern of shelterbelts, therefore, much attention should be paid to construct farmland shelterbelts in the study area.

关键词： farmland shelterbelt spatial heterogeneity Spot 5 distance coefficient

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Atomic force microscope study of WC-10Co cemented carbide sintered from nanocrystalline composite powders

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Journal of University of Science and Technology Beijing 2005年第6期12卷 558-563页

作者： xiaoliang shi Gangqin Shao Xinglong Duan Runzhang Yuan State Key Laboratory of Advanced Technology for Materials Synthesis ＆ Processing Wuhan University of Technology Wuhan 430070 China

In order to compare the spark plasma sintedng （SPS） process plus hot isostatic press （HIP） with vacuum sintedng plus HIP, an investigation was carried out on the topography, microstructure and gain size distribution of nanocrystalline WC-10Co composite powder and the sintered specimens prepared by SPS plus HIP and by vacuum sintering plus HIP by means of atomic force microscopy （AFM）. The mechanical properties of the sintered specimens were also investigated. It is very easy to find cobalt lakes in the specimen prepared by vacuum sintering plus HIP process. But the microstructure of the specimen prepared by SPS plus HIP is more homogeneous, and the grain size is smaller than that prepared by vacuum sintering plus HIP. The WC-10Co ultrafine cemented carbide consolidated by SPS plus HIP can reach a relative density of 99.4%, and the transverse rupture strength （TRS） is higher than 3540 MPa, the Rockwell A hardness （HRA） is higher than 92.8, the average grain size is smaller than 300 nm, and the WC-10Co ultrafine cemented carbide with excellent properties is achieved. The specimen prepared by SPS with HIP has better properties and microstructure than that prepared by vacuum sintering with HIP.

关键词： WC-10Co nanocrystalline composite powder atomic force microscopy (AFM) spark plasma sintering (SPS) hot isostatic pressing (HIP)

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Study on the diamond/ultrafine WC-Co cermets interface formed in a SPS consolidated composite

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Rare Metals 2006年第2期25卷 150-155页

作者： shi xiaoliang SHAO Gangqin DUAN Xinglong YUAN Runzhang State Key Laboratory of Advanced Technology for Materials Synthesis ＆ Processing Wuhan University of Technology Wuhan 430070 China

Nanocrystalline WC-Co composite powder and coated tungsten diamond by using vacuum vapor deposition were consolidated by the spark plasma sintering （SPS） process to prepare diamond-enhanced WC-Co cemented carbide composite materials. The interface microstructures between coated tungsten diamond and WC-Co cemented carbide matrix were investigated by scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDXS）. The results showed that there is a transitional layer between the diamond and the matrix, in which the carbon content is 62.97wt.%, and the content of cobalt in the transitional zone is 6.19wt.%; the content of cobalt in the WC-Co cemented carbide matrix is 6.07wt.%, in which the carbon content is 15.95wt.%, and the content of cobalt on the surface of diamond is 7.30wt.%, in which the carbon content is 80.38wt.%. The transitional zone prevents the carbon atom of the diamond from spreading to the matrix, in which the carbon content does coincide with the theoretical value of the raw nanocomposite powders, and the carbon content forms a graded distribution among the matrix, transitional zone, and the surface of diamond; after the 1280℃ SPS consolidated process the diamond still maintains a very good crystal shape, the coated tungsten on the surface of the diamond improves thermal stability of the diamond and increases the bonding strength of the interface between the diamond and the matrix.

关键词： diamond nanocrystalline WC-Co composite powders interface spark plasma sintering

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Effects of groove-textured surfaces filled with Sn-Ag-Cu and MXene-Ti_(3)C_(2) composite lubricants on tribological properties of CSS-42L bearing steel

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Friction 2022年第7期10卷 1091-1113页

作者： Yawen XUE Chaohua WU xiaoliang shi Qipeng HUANG Ahmed Mohamed Mahmoud IBRAHIM School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan 430070China Shenzhen Research Institute of Wuhan University of Technology Shenzhen 518000China Department of Production Engineering and Mechanical Design Faculty of EngineeringMinia UniversityEI-Minya 61519Egypt

To improve the tribological performance of CSS-42L bearing steel,smooth surfaces(SSs),groovetextured surfaces(GSs),GSs with Sn-Ag-Cu(GSs-SAC),and GSs with Sn-Ag-Cu-Ti_(3)C_(2)(GSs-SACT)were prepared on *** addition,experimental studies were conducted on tribological *** obtained results indicated that GSs-SACT exhibited the best anti-friction and noise reduction *** remarkable tribological performances were attributed to the synergistic effects of grooves,Sn-Ag-Cu,and MXene-Ti_(3)C_(2).The inconsistent rules of frictional forces were improved by the grooves and SACT,which inhibit the friction-induced *** micro-nano size-effects of MXene-Ti_(3)C_(2) enhanced the repairing effect and anti-friction property of composite lubricants,which improved the profile characteristics of GSs-SACT.

关键词： CSS-42L MXene Sn-Ag-Cu-Ti_(3)C_(2)(SACT) grooves tribological properties friction-induced noise

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Tribological Behaviors of Ni_3Al Intermetallics with MoO_3 Multilayer Ribbon Crystal Prepared by Spark Plasma Sintering

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Acta Metallurgica Sinica(English Letters) 2017年第6期30卷 576-584页

作者： Wenzheng Zhai xiaoliang shi Kang Yang Yuchun Huang Liping Zhou Wenlong Lu The State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology School of Mechanical and Electronic Engineering Wuhan University of Technology

This study reports that small amounts of MoO3 multilayer ribbon crystal （MOO3 MLRC） in Ni3Al intermetallics showed the decreased friction coefficients and improved wear resistance at different contact loads. Specifically, the friction coefficients （0.32-0.34） and wear rates [（2-4）× 10^-5 mm^3 N^-1 m^-1] are significantly reduced for NiaAl at 2-8 N. A possible explanation for the friction and wear reduction is that MoO3 MLRC as a multilayer material shears easily in the tribo-layer during the sliding contact, and provides low friction. In addition, this MoO3 MLRC with excellent bending strength is found to dissipate shear stress and suppress severe plastic deformation under a cyclic stress, thus drastically improving wear resistance of Ni3Al.

关键词： Intermetallics Tribologicai properties Powder metallurgy Microstructure Wear resistant

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入炉煤总氯量对粗苯含氯超标的影响分析

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煤质技术 2024年第3期39卷 93-96页

作者：史晓亮陈昌华古卫军史治澄山西金岩能源科技有限公司山西吕梁032300

粗苯为1种重要的化工原料,其主要用于深加工制苯、甲苯、二甲苯等产品。粗苯含氯高会严重腐蚀管道,对后续苯加氢等深加工利用带来危害。经对化工产品生产工艺以及入炉煤综合分析研判,基于粗苯含氯情况重点从入炉煤、介质、冷却器清洗、... 详细信息

粗苯为1种重要的化工原料,其主要用于深加工制苯、甲苯、二甲苯等产品。粗苯含氯高会严重腐蚀管道,对后续苯加氢等深加工利用带来危害。经对化工产品生产工艺以及入炉煤综合分析研判,基于粗苯含氯情况重点从入炉煤、介质、冷却器清洗、换热设备串漏等方面排查粗苯含氯增高的影响因素,并结合煤中氯的释放、洗煤对精煤含氯的影响探讨入炉煤含氯量与粗苯含氯量的关系。结果表明:高氯煤是造成粗苯含氯升高的直接因素,煤在碳化室热解过程中,煤中氯离子会以HCl的形式析出并进入荒煤气与化产回收系统中。当入炉煤总氯量偏高时,严重影响粗苯等化工产品的质量。在化工产品生产工艺正常的情况下,入炉煤中总氯含量应低于0.1%,以保证粗苯含氯量控制在10μg/g以内。

关键词：粗苯含氯量入炉煤总氯量线性关系生产工艺影响因素换热设备

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辽东山区5种林分土壤颗粒分形特征与土壤性质

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东北林业大学学报 2024年第9期52卷 99-108页

作者：邓继峰万龙燕侯瑞萍李景浩武斌韩明石小亮沈阳农业大学沈阳110866 国家林业和草原局林草调查规划院国家林业局森林病虫害防治总站辽宁省交通高等专科学校沈阳有色冶金设计研究院有限公司

选取清原县森林内林龄、坡向、坡位基本相同的林分类型,包括天然红松(Pinus koraiensis)林、樟子松(Pinus sylvestris ***)人工林、蒙古栎(Quercus mongolica)人工林、胡桃楸(Juglans mandshurica)人工林、天然针阔混交林(红松和蒙古栎... 详细信息

选取清原县森林内林龄、坡向、坡位基本相同的林分类型,包括天然红松(Pinus koraiensis)林、樟子松(Pinus sylvestris ***)人工林、蒙古栎(Quercus mongolica)人工林、胡桃楸(Juglans mandshurica)人工林、天然针阔混交林(红松和蒙古栎数量比为2∶8),设置无乔木覆盖样地作为对照,对比分析天然条件不同林分土壤粒度组成、平均粒径、标准偏差、偏度、峰态值和(单、多重)分形维数,土壤理化性质空间分布及与分形维数之间的关系。结果表明:有林地表层(0~20 cm)和亚表层(20~40 cm)土壤组成以砂粒为主,粉粒、黏粒次之;粒度特征整体呈现分选状况极好、偏度正和峰态为尖窄的特点,土壤单重分形维数在1.84~2.78之间;有林地土壤平均粒径、单重分形维数及土壤理化性质均高于对照样地,且从针叶林、阔叶林至针阔混交林,上述土壤指标呈现递增趋势;多重分形维数表现为容量维数>关联维数>信息维数;单重分形维数和容量维数与黏粒和粉粒体积分数及土壤理化性质呈显著正相关关系,综合说明土壤细粒物质在有林地的保护中逐渐恢复,且表层土壤的恢复效果较好;多重分形维数分析表明,土壤粒径非理想均匀分布,因此,利用单重分形维数结合多重分形参数评价土壤质量仍有必要。

关键词：林分类型土壤性质土壤粒度特征辽东山区

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Tribological Properties of TiAl-Ti_3SiC_2 Composites

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Journal of Wuhan University of Technology(Materials Science) 2014年第2期29卷 256-263页

作者：薛冰 XU Zengshi ZHANG Qiaoxin shi xiaoliang WANG Mang ZHAI Wenzheng YAO Jie SONG Siyuan School of Mechanical and Electronic Engineering Wuhan University of Technology Department of Mechanical and Electronic Engineering Yellow River Conservancy Technical Institute

The tribological properties of TiAl-Ti_3SiC_2 composites （TMC） against Si_3N_4 ceramic ball pair at room temperature were investigated through the determination of friction coefficients and wear rates, and the morphologies and compositions of wear debris, worn surfaces of TMC and Si_3N_4 ceramic ball were analyzed. The experimental results showed that TMC with 15wt% Ti_3SiC_2 exhibited relatively excellent tribological properties. The solid-phase self-lubricating tribo-layers formed on the worn surfaces of both TMC with 15wt% Ti, SiC, and Si,NA ceramic ball, which was beneficial to the lower friction coefficient and wear rate.

关键词： TiAI-Ti_3SiC_2 composites spark plasma sintering in situ technique tribological properties

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