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东非大裂谷的地壳和上地幔密度结构

地质论评 2024年第1期70卷 1-8页

作者：钱知之杨文采浙江大学杭州310058

利用卫星重力场数据和小波多尺度分析方法对东非大裂谷进行三维密度结构成像,取得了东非大裂谷地壳和上地幔多个深度等效层上的密度扰动图像,为东非大裂谷岩石圈结构和动力学的研究提供了重要佐证。结果表明,东非大裂谷中段的西支裂谷... 详细信息

利用卫星重力场数据和小波多尺度分析方法对东非大裂谷进行三维密度结构成像,取得了东非大裂谷地壳和上地幔多个深度等效层上的密度扰动图像,为东非大裂谷岩石圈结构和动力学的研究提供了重要佐证。结果表明,东非大裂谷中段的西支裂谷与东支裂谷的幔源熔体同源,但是西支裂谷发育较不充分、形成较晚。东非大裂谷的动力学模式为熔流体上涌的树形分叉模式,其要点包括:(1)低密度流体在软流圈大面积上涌;(2)流体在岩石圈继续上涌,部分转化为基性岩浆岩,平面面积缩小;(3)进入地壳后上涌熔流体分叉成多支,平面总面积进一步缩小;(4)熔流体上涌到上地壳后仅在裂谷带活动,反映为火山链和玄武岩带。

关键词：东非大裂谷卫星重力场小波多尺度分析三维密度结构成像熔流体运动

玉米秸秆及其生物炭复配基质对玉米根系构型的影响

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华南农业大学学报 2024年第2期45卷 207-217页

作者：张立芸黎力张海东杨文彩云南农业大学机电工程学院云南昆明650201

【目的】研究玉米Zea mays L.秸秆及其生物炭对设施栽培中基质改良的价值,探明玉米根系构型及其对不同复配基质的响应。【方法】采用盆栽试验,测定并分析了不同配比基质的理化性质和玉米地上部、根系生物量,采用WinRHIZO(Pro.2020a)根... 详细信息

【目的】研究玉米Zea mays L.秸秆及其生物炭对设施栽培中基质改良的价值,探明玉米根系构型及其对不同复配基质的响应。【方法】采用盆栽试验,测定并分析了不同配比基质的理化性质和玉米地上部、根系生物量,采用WinRHIZO(Pro.2020a)根系分析系统分析计算玉米根系的形态以及分形、拓扑结构特征参数,采用SPSS软件分析地上部/根系生物量、根系形态特征与构型特征参数的相关性。【结果】添加秸秆及其生物炭的各处理中,T3处理(蛭石、珍珠岩、玉米秸秆和玉米秸秆生物炭的添加量分别为22.4、22.4、22.4和44.8 dm^(3))的理化性质相较CK最为优化,总孔隙度和持水孔隙度分别达到81.02%和55.38%,可利用的速效氮、磷、钾含量均处在最优水平。T3处理根系的生物量和根长、根表面积、根体积3个主要形态特征参数均与其他处理差异显著,分别高于CK处理112.82%、79.89%、101.21%和102.53%。随着秸秆及其生物炭添加比例的增加,各处理根系分形维数逐渐增大,从CK的1.425增大至T3的1.514;拓扑指数逐渐减小,从CK的0.699减小至T3的0.627,T3处理的拓扑指数更接近0.5。玉米根系生物量和主要形态特征参数与分形维数、分形丰度呈极显著正相关,与拓扑指数呈极显著负相关。【结论】添加秸秆及其生物炭可改善基质理化性质,为根系提供优质生长环境;环境对根系构型的可塑性较高,可以使玉米根系构型向更利于养分和水分利用的方向改变;根系构型性状可在一定程度上表征根系形态特征,也可作为指标来验证复合基质的栽培效果。

关键词：玉米玉米秸秆生物炭根系构型分形维数拓扑指数

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蔬菜穴盘育苗播种机清种装置的设计与试验

华南农业大学学报 2024年第1期45卷 116-126页

作者：杨文彩田梓园潘吴建赵静张海东李贵荣云南农业大学机电工程学院云南昆明650201 宁波财经学院浙江宁波315175

【目的】针对蔬菜穴盘育苗播种机现有清种装置清种效果不好,导致的充种合格率低、重播率高问题,设计集机械式、气吹式、电控式为一体的清种装置。【方法】结合运动学及动力学理论对三级清种装置的结构进行设计;采用Ansys软件中Fluent模... 详细信息

【目的】针对蔬菜穴盘育苗播种机现有清种装置清种效果不好,导致的充种合格率低、重播率高问题,设计集机械式、气吹式、电控式为一体的清种装置。【方法】结合运动学及动力学理论对三级清种装置的结构进行设计;采用Ansys软件中Fluent模块对气吹式清种装置的不同进气口和出气口结构中的气流稳定性进行分析;在理论分析和仿真分析的基础上选取排种器转速、排种器负压、清种装置正压、种子直径为试验因素,结合农艺要求选取单粒充种合格率、重播率为试验指标开展四因素三水平二次回归正交试验。根据试验数据得出最佳参数组合。【结果】由仿真分析得出,中间端进气圆弧式喷嘴气吹式清种结构清种效果最好。由台架试验得到排种最佳参数组合,即在排种器转速为0.17 r/s、种子直径为1.5 mm、排种器负压为0.6 kPa、气吹式清种装置正压为0.3 kPa时,平均单粒充种合格率为95.31%,平均重播率为0.2%。【结论】本文设计的清种装置满足了蔬菜播种农艺要求,可以有效提升充种合格率、降低重播率,为生产实际提供理论指导。

关键词：蔬菜穴盘育苗播种机清种装置二次回归正交试验

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基于响应面法和CFD的轴流气吸式排种器优化设计

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中国农机化学报 2024年第8期45卷 14-19页

作者：张宇乾于淇胡志诚陈龙杨文彩张海东云南农业大学机电工程学院昆明市650201

为提高轴流气吸式排种器型孔入口处的负压从而提升吸种效率,采用响应面法和CFD软件对排种器结构参数进行试验设计和数值模拟并进行回归分析,得到排种器结构最佳参数组合。使用中央复合设计(CCD)对排种器结构参数进行试验设计并建立15组... 详细信息

为提高轴流气吸式排种器型孔入口处的负压从而提升吸种效率,采用响应面法和CFD软件对排种器结构参数进行试验设计和数值模拟并进行回归分析,得到排种器结构最佳参数组合。使用中央复合设计(CCD)对排种器结构参数进行试验设计并建立15组试验模型,使用FLUENT软件对试验模型的型孔入口压力值进行数值计算,将所得数据集导入Design-Expert软件并通过响应面法进行预测和寻优,得到的最佳参数组合为:扇叶转速为2393 r/min,扇叶个数为11,型孔数为15,此时目标函数预测型孔进口处的负压为210.07 Pa。为验证响应面法目标函数预测值的准确性,进行数值模拟试验和台架试验。结果表明,数值模拟法和响应面法的目标函数值基本一致,而台架法与数值模拟法的误差为6.2%。

关键词：轴流气吸式排种器响应面法计算流体动力学数值模拟

肺力咳合剂联合盐酸氨溴索和阿奇霉素治疗老年支原体肺炎患者的效果

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中国民康医学 2024年第4期36卷 117-119页

作者：王长福羊文彩周玉茹上蔡仁爱医院内科河南驻马店463800

目的:观察肺力咳合剂联合盐酸氨溴索和阿奇霉素治疗老年支原体肺炎患者的效果。方法:选取2020年1月至2022年1月该院收治的80例老年支原体肺炎患者进行前瞻性研究,按照随机数字表法分为观察组与对照组各40例。对照组采用盐酸氨溴索联合... 详细信息

目的:观察肺力咳合剂联合盐酸氨溴索和阿奇霉素治疗老年支原体肺炎患者的效果。方法:选取2020年1月至2022年1月该院收治的80例老年支原体肺炎患者进行前瞻性研究,按照随机数字表法分为观察组与对照组各40例。对照组采用盐酸氨溴索联合阿奇霉素治疗,观察组在对照组基础上加用肺力咳合剂治疗,比较两组治疗总有效率,发热、咳嗽、咳痰、肺部干湿啰音等临床症状消失时间和住院时间,血清炎性因子[细胞间黏附分子-1(ICAM-1)、白细胞介素-1β(IL-1β)和C反应蛋白(CRP)]水平,肺功能指标[最大呼气峰流速(PEF)、第1秒用力呼气容积(FEV_(1))/用力肺活量(FVC)]水平和不良反应发生率。结果:观察组治疗总有效率为95.00%,明显高于对照组的72.50%,差异有统计学意义(P0.05)。结论:肺力咳合剂联合盐酸氨溴索和阿奇霉素治疗老年支原体肺炎患者可提高治疗总有效率和肺功能指标水平,缩短发热、咳嗽、咳痰、肺部干湿啰音消失时间和住院时间,降低炎性因子水平,效果优于单纯盐酸氨溴索和阿奇霉素治疗。

关键词：老年支原体肺炎盐酸氨溴索肺力咳合剂肺功能炎性因子

Design and experiment of the soil-covering and soil-compacting device for seedling raising and sowing of trough type panax notoginseng

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International Journal of Agricultural and Biological Engineering 2023年第5期16卷 113-122页

作者： wencai yang Wang Pu Lulu Xu Ziyuan Tian Jing Zhao Yijie Zhang Zhenjie yang College of Mechanical and Electrical Engineering Yunnan Agricultural UniversityKunming 650201China Agricultural and rural Bureau Southwest Guizhou 562499China

In order to improve the seedling quality of Panax notoginseng,combined with the special agronomic requirements of Panax notoginseng,a sharp angle roller soil-covering and soil-compacting device integrating the functions of soil-covering and soil-compacting was *** on the theoretical analysis of seed ditch conditions,soil-covering process and soilcompacting process,the structure of soil-covering and soil-compacting device was *** theoretical analysis and calculation,the diameter and length of soil-covering and soil-compacting wheel were 20 cm and 10.7-14.1 cm,respectively,the sharp angle and height range were 45°-105°and 0.8-1.6 cm respectively,and the spring stiffness was 38.54 N/mm;Using the discrete element method to simulate the soil-covering and soil-compacting process,it was obtained that when the sharp angle range was 60°-90°,the sharp angle height range was 0.8-1.2 cm,and the soil-covering effect was better;Taking the forward speed,ballast pressure,sharp angle and sharp angle height of the planter as the test factors,and taking the soil-covering thickness,grain spacing and soil compactness as the indexes,the four factor and three-level Box-Behnken Design test was carried *** response surface test analysis method was used to establish the regression equation between the factors and indexes,and determine the best parameter combination:the forward speed was 6.5 m/min,the ballast pressure was 360.5 N,the sharp angle was 67°,and the sharp angle height was 1 cm,at this time,the soil-covering thickness was 0.64 cm,the grain spacing was 5.03 cm,and the soil compactness was 321.77 *** to the soil trough test,the design of soil-covering and soil-compacting device met the agronomic requirements of plant spacing,soil-compactness and soil-covering thickness during seedling sowing of Panax *** research results can provide a reference for the design of Panax notoginseng seedling planter integrating pressing hole(ditching),so

关键词： Panax notoginseng trough type seedling raising and sowing soil-covering and soil-compacting EDEM test

A review on developments in the electrical structure of craton lithosphere

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Science China Earth Sciences 2020年第11期63卷 1661-1677页

作者： Xiangyun HU Wule LIN wencai yang Bo yang Hubei Subsurface Multiscale Imaging Laboratory Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China School of Earth Sciences Zhejiang UniversityHangzhou 310058China

Cratons have a long history of *** this paper,applications of the magnetotelluric method used in the study of craton lithosphere over the past 30 years were reviewed,examining case studies of cratons in North America,South America,Asia,Australia,and *** nuclei of the Archean cratons,for example the Kalahari Craton and Rae Craton,are usually characterized by thick and highly resistive lithospheric *** or after the formation of the cratons,tectonothermal events,such as collision,mantle plume,and asthenosphere upwelling led to the formation of high-conductivity zones in the craton lithosphere,which could be attributed to the increased hydrogen content(of nominally anhydrous minerals),higher iron content,and formation of graphite films or sulfides along the grain boundary of *** conductive zones are characterized by resistivity discontinuities in craton *** particular,the conductive zones include(1)large-scale lithospheric mantle conductors beneath the Slave Craton,Gawler Craton,and central part of North China Craton(Trans-North China Orogen);(2)near-vertical high-conductivity zone associated with the fossil subduction zone beneath the Dharwar Craton and Slave Craton;and(3)regional lateral electrical discontinuities,such as a conductive anomaly under the Bushveld Complex of the Kaapvaal *** eMoho refers to the electrical discontinuity in the crust-mantle *** existing research,this has been detected under the condition of extremely high lithospheric resistivity with only a slight decrease in the lower crust,and in the case of a very thin conductive lower crust or the lack *** the resistivity model,the unique"mushroom-like"lower crust-lithosphere mantle conductor and very thin lower crust layer of the North China Craton may represent lithosphere destruction and/or *** also find that some of the cratons are still not well ***,extensive three-dimensional inversion and joint interpr

关键词： Craton Lithospheric electrical structure Magnetotellurics

Deep decalcification of factory-provided freezing acidolysis solution to achieveα-high-strength gypsum

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Chinese Journal of Chemical Engineering 2024年第5期69卷 143-151页

作者： wencai Ye Yulu Li Yonggang Dong Lin yang Yun Yi Jianxin Cao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China Engineering Research Center of Efficient Utilization for Industrial Waste Guizhou UniversityGuiyang 550025China Key Laboratory of Guizhou Province for Green Chemical Industry and Clean Energy Technology Guizhou UniversityGuiyang 550025China

The freezing acidolysis solution of the nitric acid-phosphate fertilizer process has a high calcium content,which makes it difficult to produce fine phosphate and high water-soluble phosphate fertilizer ***,based on the potential crystallization principle of calcium sulfate in NH_(4)NO_(3)-H_(3)PO_(4)-H_(2)O,the deep decalcification(*** removal)technology to achieveα-high-strength gypsum originated from freezing acidolysis-solutions has been firstly proposed and ***,calcium can be removed from the factory-provided freezing acidolysis-solution by neutralizing it with ammonia,followed by the addition of ammonium sulfate *** a result,the formation of calcium sulfate in the reaction system undergoes the nucleation and growth of CaSO_(4)·2H_(2)O(DH),as well as its dissolution and crystallization into short columnarα-CaSO_(4)·0.5H_(2)O(α-HH).Remarkably,with the molar ratio of SO_(4)^(2-)/Ca^(2+)at 1.8,the degree of neutralization(NH_(3)/HNO_(3) molar ratio)at 1.7,the reaction temperature of 94℃,and the reaction time of 300 min,the decalcification rate can reach 86.89%,of which the high-strengthα-CaSO_(4)·0.5H_(2)O(α-HH)will be ***,the deep decalcification product meets the standards for the production of fine phosphates and highly water-soluble phosphate ***,the 2 h flexural strength ofα-HH is 5.3 MPa and the dry compressive strength is 36.8 MPa,which is up to the standard of commercialα-HH.

关键词： Nitrophosphate Ammonia neutralization Deep decalcification High-strengthα-hemihydrate gypsum Controlled crystallization at atmospheric pressure

Multi-scale inversion of density structure from gravity anomalies in Tarim Basin

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Science China Earth Sciences 2011年第3期54卷 399-409页

作者： HOU ZunZe yang wencai Chinese People's Armed Police Force Academy Langfang 065000 China Institute of Geology Chinese Academy of Geology Beijing 100037 China

Based on the power spectra of gravity anomalies in Tarim Basin, the anomalies can be decomposed to the following three components: a sub-anomaly formed mainly by the basin crystallized basement, a sub-anomaly formed mainly by deep sedimentary layers, and that by shallow sedimentary layers. A special wavelet transform analysis scheme and a density inversion method are designed and applied to the decomposition and inversion of gravity sub-anomalies, which are correlated with regional geology and drilling data. The results indicate that the deep and the shallow sub-anomalies show some relations with ancient fluid active zones. The negative density disturbances inversed from the shallow sub-anomaly are mainly caused by Mesozoic fluid active zones, whereas the negative density disturbances form the deep sub-anomalies are mainly correlated with Paleozoic fluid active zones. As the ancient fluid movement was good for formation of oil/gas fields, the multi-scale inversion methods for locating the ancient fluid movement zones seem to be helpful and valuable to oil/gas exploration.

关键词：塔里木盆地多尺度反演重力异常密度结构反演方法密度扰动天然气勘探古流体