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Effects of Plant Density Regulation on Soil Physical Properties and Plant Diversity of Plantations in Yellow River Flood Plain of Northern Shandong Province [PDF]
, 2022 [Objective] The effects of plant density regulation on soil physical properties and plant diversity of different plant stands in the Yellow River flood plain were analyzed in order to provide a theoretical basis for optimizing stand growth, improving ...
Chen Ping +3 more
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Nonlinear free vibration analysis of Timoshenko beams with porous functionally graded materials
Xibei Gongye Daxue Xuebao, 2022 基于Timoshenko梁变形理论研究多孔功能梯度材料梁的非线性自由振动问题。针对多孔功能梯度材料梁的孔隙均匀分布和孔隙线性分布2种形式, 根据广义Hamilton原理推导多孔功能梯度材料Timoshenko梁的非线性自由振动的控制微分方程组并对方程组进行无量纲化。采用微分变换法(DTM)对各种边界条件下的控制微分方程组进行变换, 得到等价代数特征方程。计算了多孔功能梯度材料Timoshenko梁在固支-固支(C-C)、固支-简支(C-S)、简支-简支(S-S)和固支-自由(C-F ...
TENG Zhaochun, MA Lingquan, FU Xiaohua
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Shuitu Baochi Xuebao, 2021 采用X-ray computed tomography（CT）技术研究了果树行间不同油菜间作密度（CK：清耕；L：低密度间作；M：中密度间作；H：高密度间作）对土壤大孔隙特征参数的影响。结果表明：油菜间作改善了果树行间（0—60 cm）土壤大孔隙特征，各土层的土壤大孔隙数量、大孔隙面积、大孔隙度等参数分别较清耕显著提高（P 1 mm）在各土层间的数目多、差异小，并且在0—30 cm土壤剖面上的成圆率最高。中、高密度油菜间作的土壤大孔隙特征参数均优于清耕及低密度间作，而中密度间作的土壤大孔隙分布更均匀 ...
何娜娜 +4 more
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Simulation study of factors influencing oil yield during cold pressing of rapeseed [PDF]
, 2023 Objective: This study aimed to investigate the factors influencing the oil yield of rapeseed during pressing in a double screw oil press. Methods: To simulate the pressing process of rapeseed and to explore the effects of two factors, the speed of the ...
HUANG Tao +3 more
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Shuitu Baochi Xuebao, 2023 以明确自然界中广泛存在的层状结构土壤孔隙分布特征为目的。选黄土高原典型坝地土壤剖面为研究对象,利用CT扫描技术分析耕作层、犁底层、心土层土壤三维结构,探讨层状土孔隙参数随土层结构变化及界面层孔隙特征。结果表明:(1)瘦长型孔隙(孔隙形状系数≤0.2)是各土层土壤孔隙的主要形态。各土层的孔隙参数具有明显差异。耕作层的总孔隙度最高,大孔隙(≥1 mm)分布较多;犁底层孔隙总数量最高,含有较多孤立的小孔隙(≥0.1~0.5 mm)和微小孔隙(≥0.06~0.1 mm),但连通性最差 ...
张佐源 +5 more
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Numerical study on anti-impact characteristics of energy absorbing column with multicellular square tube filled with aluminum foam [PDF]
, 2023 Aiming at the insufficient anti-impact performance of existing components of the energy-absorbing anti-impact support, a foam aluminum filled multicellular square tube structure is proposed.
Heng ZHU +5 more
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Shuitu Baochi Xuebao, 2023 为了明确农业生产过程中耕作方式对田间土壤孔隙结构及土壤水分运动特性的影响,以广西农地蔗田为研究对象,基于土壤切片技术分析研究免耕和垄耕2种典型耕作方式蔗田的田间土壤孔隙结构特征,并结合土柱模拟入渗试验,探究土壤孔隙结构对土壤水分运动的影响,进一步揭示孔隙结构与土壤水分运动特性之间的相互作用关系。结果表明:随着土层深度的增加,免耕蔗田孔隙形态以聚集的团块状分布为主,垄耕蔗田孔隙形态以条状分布为主。与免耕蔗田相比,垄耕蔗田的土壤总孔隙度和＞2.5 mm孔径的孔隙度分别增加32.5%和21.9 ...
刘俊杰 +5 more
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, 2018 针对我国荒漠化危害严重,不利于植物种植等系列问题,以番茄为试验材料,结合纸膜、保水剂、生物基固沙剂等不同保水固沙措施,分析各处理下基质的理化性质以及番茄的生物学性状,以探明各处理对沙地环境的改善效果及对番茄生长的影响,为沙漠的防治及沙产业的发展提供参考。结果表明:瓦楞纸处理显著提高了番茄果实的有机酸、可溶性糖含量,分别比CK高27. 78%、8. 87%,其pH值比CK高0. 89,速效氮含量是CK的40倍;牛皮纸处理20~40 cm含水量比CK高73.
兰挚谦 +10 more
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Selective Dissolution of Clay Minerals in Tight Sandstone by Organic Acids [PDF]
, 2023 BACKGROUNDImproving the prediction ability of relatively high-quality reservoirs under tight backgrounds is a bottleneck and a challenge in current oil and gas exploration and development theories.
Bo DONG +4 more
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Water-holding Capacity of Reclaimed Grassland with Different Ages in Karst Regions [PDF]
, 2023 [Objective] The water-holding capacity of reclaimed grassland of different ages was studied in order to provide a scientific basis for water retention and soil and water conservation of reclaimed grassland in karst regions.
Li Xuemei +3 more
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