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Straw layer burial to alleviate salt stress in silty loam soils: Impacts of straw forms

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Journal of Integrative Agriculture 2020年第1期19卷 265-276页

作者： zhang hong-yuan LU Chuang PANG Huan-cheng LIU Na zhang Xiao-li LI Yu-yi Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

Salt stress can be alleviated by straw layer burial in the soil, but little is known of the appropriate form of the straw layer for optimal regulation of soil water and salinity because of the uncontrollability of field tests. Here, the following four straw forms with compaction thickness of 5 cm buried 40–45 deep were studied: no straw layer(CK), segmented straw(SL, 5 cm in length), straw pellet(SK), and straw powder(SF). The three straw forms(SL, SK and SF) significantly delayed the infiltration of irrigation water down the column profile by 71.20–134.3 h relative to CK and the migration velocity of the wetting front under SF was the slowest. It took longer for the wetting front to transcend SK than SL but shorter for it to reach the bottom of soil column after water crossed the straw layer. Compared with CK, the average volumetric water content in the 0–40 cm soil layer increased by 6.45% under SL, 1.77% under SK and 5.39% under SF. The desalination rates at the 0–40 and 0–100 cm soil layers increased by 5.85 and 3.76% under SL, 6.64 and 1.47% under SK and 5.97 and 4.82% under SF. However, there was no significant difference among straw forms in the 0–40 cm soil layer. Furthermore, the salt leaching efficiency(SLE, g mm^–1 h^–1) above the 40 cm layer under SL was 0.0097, being significantly higher than that under SF(0.0071) by 37.23%. Salt storage under SL, SK and SF in the 40–45 cm layer accounted for 4.50, 16.92 and 7.43% of total storage in the 1-m column profile. Cumulative evaporation under SL and SF decreased significantly by 41.20 and 49.00%, with both treatments having the most significant inhibition of salt accumulation(resalinization rate being 36.06 and 47.15% lower than CK) in the 0–40 cm soil layer. In conclusion, the different forms of straw layers have desalting effects under high irrigation level(446 mm). In particular, SL and SF performed better than SK in promoting deep salt leaching and inhibiting salt accumulation on the soil surface. However,

关键词： straw layer segmented straw with 5 cm length straw pellet straw powder infiltration evaporation water and salt distribution

Maize straw application as an interlayer improves organic carbon and total nitrogen concentrations in the soil profile: A four-year experiment in a saline soil

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Journal of Integrative Agriculture 2023年第6期22卷 1870-1882页

作者： CHANG Fang-di WANG Xi-quan SONG Jia-shen zhang hong-yuan YU Ru WANG Jing LIU Jian WANG Shang JI hong-jie LI Yu-yi Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China The Norwegian Institute of Bioeconomy Research(NIBIO) As 1431Norway Department of Soil and Plant Microbiome Institute of PhytopathologyChristian-Albrechts-University of KielKiel 24118Germany

Soil salinization is a critical environmental issue restricting agricultural *** return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt ***,the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain ***,a four-year (2015–2018) field experiment was conducted with four levels (i.e.,0,6,12and 18 Mg ha~(–1)) of straw returned as an *** with no straw interlayer (CK),straw addition increased SOC concentration by 14–32 and 11–57%in the 20–40 and 40–60 cm soil layers,*** increases in soil TN concentration (8–22 and 6–34%in the 20–40 and 40–60 cm soil layers,respectively) were lower than that for SOC concentration,which led to increased soil C:N ratio in the 20–60 cm soil *** in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm),which promoted uniform distributions of SOC and TN in the soil *** in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower ***,compared with other treatments,the application of 12 Mg ha~(–1) straw had higher SOC,TN and C:N ratio,and lower soil stratification ratio in the2015–2017 *** results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years,and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils.

关键词： straw addition interlayer soil organic carbon soil nitrogen C:N ratio saline soil

PID Parameters for Tuning and Optimization of a Turbine EngineBased on the Simplex Search Method

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International Journal of Plant Engineering and Management 2009年第4期14卷 250-254页

作者： zhang hong CAI yuan-hu CHEN Yu-chun School of Power and Energy Northwestern Polytechnical University Xi'an 710072 R.R. China

A PID parameters tuning and optimization method for a turbine engine based on the simplex search method was proposed. Taking time delay of combustion and actuator into account, a simulation model of a PID control system for a turbine engine was developed. A performance index based on the integral of absolute error （IAE） was given as an objective function of optimization. In order to avoid the sensitivity that resulted from the initial values of the simplex search method, the traditional Ziegler-Nichols method was used to tune PID parameters to obtain the initial values at first, then the simplex search method was applied to optimize PID parameters for the turbine engine. Simulation results indicate that the simplex search method is a reasonable and effective method for PID controller parameters tuning and optimization.

关键词： turbine engine PID (proportion integral and differential) control simplex search method tuning optimization

A MATHEMATICAL MODEL FOR UNSTEADY SEDIMENT TRANSPORT IN NINGXIA REACH OF THE YELLOW RIVER

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Journal of Hydrodynamics 2001年第4期13卷 1-7页

作者： zhang hong-yi Beijing University of Aeronautics and Astronautics, Beijing 100083, China zhang hong-wu, Huang yuan-dong, Zhong De-yu Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China Beijing University of Aeronautics and Astronautics Department of Hydraulic Engineering Tsinghua University

A one-dimensional mathematical model for unsteady sediment transport in the Ningxia reach of the Yellow River was developed. In the model, the formulas for the sediment carrying capacity and the manning roughness coefficient, which reflect the features of the Yellow River, were adopted. A coefficient of sediment distribution was defined to represent the ratio of the bottom to the average concentration under the equilibrium conditions, which is not constant and is evaluated by using an empirical expression obtained by integrating the sediment concentration along water depth. The concentration distributions and the mean diameter distributions of suspended sediment in the transversal direction were also estimated in this model. A four-point (Preismann type) finite difference scheme and TDMA were employed in the numerical simulation. The amount of sediment deposition during the period of 1993～1999 in the Ningxia reach of the Yellow River from Xiaheyan to Shizuishan with a length of 197.43km were numerically simulated with the model. The computed results, such as the amount of sediment deposition and water stage agree well with the field data. Finally the validated model was used to predict the riverbed deformation during the period of 1999～2019 in the Ningxia reach of the Yellow River.

关键词： mathematical model unsteady sediment transport Ningxia reach of the Yellow River sediment deposition flood

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矿物掺合料对混凝土抗酸雨侵蚀特性的影响

建筑材料学报 2013年第3期16卷 416-421页

作者：王凯马保国张泓源华东交通大学土木建筑学院江西南昌330013 武汉理工大学硅酸盐建筑材料国家重点实验室湖北武汉430070

通过室内加速腐蚀试验,用球压痕和超声波方法研究了含不同矿物掺合料(高钙粉煤灰、磨细高炉矿渣、硅粉)混凝土在模拟酸雨(pH=2)下的损伤劣化过程及特点.结果表明:在混凝土中掺入一定量、适宜的矿物掺合料,因其发生火山灰反应而使体系Ca(... 详细信息

通过室内加速腐蚀试验,用球压痕和超声波方法研究了含不同矿物掺合料(高钙粉煤灰、磨细高炉矿渣、硅粉)混凝土在模拟酸雨(pH=2)下的损伤劣化过程及特点.结果表明:在混凝土中掺入一定量、适宜的矿物掺合料,因其发生火山灰反应而使体系Ca(OH)2含量降低、微结构更加致密,在一定程度上延缓了酸雨对混凝土的侵蚀破坏进程,提高了混凝土的耐酸雨侵蚀能力,其中尤以高钙粉煤灰、磨细高炉矿渣和硅粉三元复掺效果最为明显,但总体上延缓作用有限,含矿物掺合料混凝土在酸雨侵蚀持续作用下仍会遭到严重侵蚀破坏.含矿物掺合料混凝土酸雨侵蚀破坏主要是H+溶蚀性破坏和SO2-4膨胀性破坏共同作用的结果.

关键词：混凝土酸雨侵蚀矿物掺合料表面损伤内部损伤

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论矿物改造机制研究

矿物岩石地球化学通报 2012年第1期31卷 52-56页

作者：张宏远地质过程与矿产资源国家重点实验室北京100083 中国地质大学(北京)地球科学与资源学院北京100083

矿物改造机制是容易被岩矿研究人员忽视的"成因矿物学"新领域之一,主要涉及矿物诞生之后的变化过程。变形矿物及岩石显微构造定性研究已经发展成熟,但造岩矿物显微构造变形与流体运动学和动力学关系的定量研究仍是地学前缘问题。从解析... 详细信息

矿物改造机制是容易被岩矿研究人员忽视的"成因矿物学"新领域之一,主要涉及矿物诞生之后的变化过程。变形矿物及岩石显微构造定性研究已经发展成熟,但造岩矿物显微构造变形与流体运动学和动力学关系的定量研究仍是地学前缘问题。从解析构造学原理出发,将国内外定量研究问题概括出三方面:(1)变形-变质期次与同变形变质温压计;(2)利用同位素年代学分析某期次变形年龄;(3)某期次矿物蠕变机制、差异应力估算及岩石流动定律。并从理论和应用两方面评述了一些实例,认为建立"成因矿物学"实验室,对于系统研究矿物学问题具有重要意义。

关键词：矿物改造机制成因矿物学解析构造学定量研究实例

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基于相关算法消除高重信号的时差定位模糊

系统工程与电子技术 2008年第5期30卷 816-818页

作者：张宏元穆贺强中国航天科工集团第二研究院二十三所北京100854

总结了多种解决高重频雷达信号时差定位模糊方法的基础上,提出了一种由相关算法推导出的新方法。该方法首先运用直方图计算出高重频信号的不同参差频率和对应的模糊时差,并在此基础上进行时差组合,然后对不同参差频率下的时差进行相关... 详细信息

总结了多种解决高重频雷达信号时差定位模糊方法的基础上,提出了一种由相关算法推导出的新方法。该方法首先运用直方图计算出高重频信号的不同参差频率和对应的模糊时差,并在此基础上进行时差组合,然后对不同参差频率下的时差进行相关运算最终得出真实的时差。计算机仿真结果表明该方法能够消除时差定位模糊,验证了其可行性和有效性。

关键词：高重频雷达信号相关算法时差定位

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基于激励阶次的失谐叶盘振动响应局部化研究

东北大学学报（自然科学版） 2016年第3期37卷 378-382页

作者：张宏远袁惠群寇海江东北大学机械工程与自动化学院辽宁沈阳110819 东北大学理学院辽宁沈阳110819

为了评估不同激励阶次和不同失谐标准差对叶盘系统结构振动的局部化影响,针对航空发动机压气机叶盘系统有限元模型,考虑榫槽和榫头的非线性接触,采用子结构模态综合法,通过引入相对振动局部化因子,研究了在不同激励阶次下的谐调和失谐... 详细信息

为了评估不同激励阶次和不同失谐标准差对叶盘系统结构振动的局部化影响,针对航空发动机压气机叶盘系统有限元模型,考虑榫槽和榫头的非线性接触,采用子结构模态综合法,通过引入相对振动局部化因子,研究了在不同激励阶次下的谐调和失谐两种情况下叶盘系统振动响应,分析不同失谐标准差下失谐叶盘系统的振动响应局部化特性,讨论了激励阶次对失谐叶盘系统位移和应变能的影响规律.结果表明,激励阶次对失谐叶盘系统频率、位移和应变能分布影响显著,随着激励阶次的增加,相对局部化因子呈现先增大再减小的趋势.

关键词：航空发动机叶盘失谐激励阶次相对局部化因子

三江南段-中南半岛特提斯蛇绿岩大地构造与成矿

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地球科学（中国地质大学学报） 2011年第2期36卷 262-276页

作者：张宏远刘俊来中国地质大学地质过程与矿产资源国家重点实验室北京100083 中国地质大学地球科学与资源学院北京100083 School of Earth Sciences the University of QueenslandSteele Building

青藏高原东南部特提斯研究是世界地质研究的热点之一,而三江南段-中南半岛地区是该研究的薄弱而分散地区.因此在特提斯构造域背景下,结合地层学、岩石学、构造学及古生物学等前人成果资料,利用中小尺度构造解析,厘定蛇绿岩混杂带构造古... 详细信息

青藏高原东南部特提斯研究是世界地质研究的热点之一,而三江南段-中南半岛地区是该研究的薄弱而分散地区.因此在特提斯构造域背景下,结合地层学、岩石学、构造学及古生物学等前人成果资料,利用中小尺度构造解析,厘定蛇绿岩混杂带构造古地理并论述成矿规律具有重要意义.(1)在特提斯构造格局基础上,圈定出与蛇绿岩空间配套的构造岩浆带,并厘定了缝合带的展布和消减极性规律,建立了构造古地理图,从中可以看出古、中、新特提斯变形依次变弱.(2)古特提斯蛇绿岩带典型蛇绿岩区的地质构造解析研究表明其经历印支期以来多期强烈构造活动改造.(3)蛇绿岩带对部分重要矿产资源的形成及分布具有显著控制作用:蛇绿岩带内的超基性岩是岩浆型钴、镍矿带的重要成矿物质来源;洋壳关闭及板块碰撞过程中形成的与蛇绿岩带平行分布的大面积酸性岩浆是热液型钨锡矿带的重要物质来源;中新世前后的构造转折促进了全区热液型矿床的形成.

关键词：特提斯蛇绿岩大地构造构造转折成矿作用