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中国塑料薄膜覆盖农业

陈奇恩

《中国工程科学》 2002年 第4卷 第4期   页码 12-15

摘要：

全面论述了塑料薄膜覆盖农业的研究与应用。地膜覆盖对我国传统覆盖技术产生重大突破，近20年以来，由于地膜覆盖的应用使我国农业产生了许多重大变革：扩大了适种区，调整了作物布局，提高了复种指数，促进了干旱、半干旱和盐碱地区的农业发展。地膜覆盖的增产机理是：提高土壤温度，保蓄土壤水分，稳定土壤环境，提高光、热利用效率和促进作物根系发育。提出了塑料薄膜覆盖的问题与展望。

关键词： 地膜覆盖     生产突破     机理效应    

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Quantification of pesticide residues on plastic mulching films in typical farmlands of the North China

Baoyuan Guo, Jiao Meng, Xinyu Wang, Chengnan Yin, Weiyu Hao, Baiwen Ma, Zhang Tao

《环境科学与工程前沿（英文）》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1181-9

摘要： Pesticide residuals on mulching film of Shandong, Tianjin and Hebei. Detected 29 pesticides in soil and 30 in mulching film. Pesticides on plastic films: 86.4‒22213.2 ng/g and in soil: 9.3‒535.3 ng/g. Pesticides on plastic films 20 times higher than in soil. Plastic debris as new pollutants attracts much attention in the recent years. The plastic mulching films is one of the most important plastic debirs source in the environment. The aim of this work was to investigate the current status of pesticide residues on the plastic mulching films. Based on the QuEChERS method, multi-residue methods for detection of pesticide residues with gas chromatography tandem mass spectrum (GC-MS) and high performance liquid chromatography tandem mass spectrum (HPLC-MS) were developed for the analysis of the pesticides residues in plastic film and soil samples from Tianjin, Hebei and Shandong. The total concentrations of pesticide residues were in the range of 86.4‒22213.2 ng/g in plastic film debris, which was about 20 times higher than that in soil (9.3‒535.3 ng/g). Residual level of pesticides varied greatly in different samples. The historical usage and recent application of pesticides were the main sources for pesticide residues on plastic films and soil. In short, plastic mulching films could act as a sink for pesticides in farmland and the ubiquitous pesticide residues on plastic films should draw more attention.

关键词： Pesticides     Plastic mulching film     Soil     QuEChERS     Farmland    

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Modeling water and heat transfer in soil-plant-atmosphere continuum applied to maize growth under plasticfilm mulching

Meng DUAN, Jin XIE, Xiaomin MAO

《农业科学与工程前沿（英文）》 2019年 第6卷 第2期   页码 144-161 doi: 10.15302/J-FASE-2019258

摘要：

Based on our previous work modeling crop growth (CropSPAC) and water and heat transfer in the soil-plant-atmosphere continuum (SPAC), the model was improved by considering the effect of plastic film mulching applied to field-grown maize in North-west China. In CropSPAC, a single layer canopy model and a multi-layer soil model were adopted to simulate the energy partition between the canopy and water and heat transfer in the soil, respectively. The maize growth module included photosynthesis, growth stage calculation, biomass accumulation, and participation. The CropSPAC model coupled the maize growth module and SPAC water and heat transfer module through leaf area index (LAI), plant height and soil moisture condition in the root zone. The LAI and plant height were calculated from the maize growth module and used as input for the SPAC water and heat transfer module, and the SPAC module output for soil water stress conditions used as an input for maize growth module. We used , the representation of evaporation resistance, instead of the commonly used evaporation resistance to reflect the change of latent heat flux of soil evaporation under film mulching as well as the induced change in energy partition. The model was tested in a maize field at Yingke irrigation area in North-west China. Results showed reasonable agreement between the simulations and measurements of LAI, above-ground biomass and soil water content. Compared with the original model, the modified model was more reliable for maize growth simulation under film mulching and showed better accuracy for the LAI (with the coefficient of determination = 0.92, the root mean square of error RMSE= 1.23, and the Nush-Suttclife efficiency E = 0.87), the above-ground biomass (with = 0.96, RMSE= 7.17 t·ha and E = 0.95) and the soil water content in 0–1 m soil layer (with = 0.78, RMSE= 49.44 mm and E = 0.26). Scenarios were considered to simulate the influence of future climate change and film mulching on crop growth, soil water and heat conditions, and crop yield. The simulations indicated that the change of LAI, leaf biomass and yield are negatively correlated with temperature change, but the growing degree-days, evaporation, soil water content and soil temperature are positively correlated with temperature change. With an increase in the ratio of film mulching area, the evaporation will decrease, while the impact of film mulching on crop transpiration is not significant. In general, film mulching is effective in saving water, preserving soil moisture, increasing soil surface temperature, shortening the potential growth period, and increasing the potential yield of maize.

关键词： film mulching     growth stage     leaf area index     maize growth     water and heat transfer    

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Experiment and optimal design of a collection device for a residual plastic film baler

Qi NIU,Xuegeng CHEN,Chao JI,Jie WU

《农业科学与工程前沿（英文）》 2015年 第2卷 第4期   页码 347-354 doi: 10.15302/J-FASE-2015077

摘要： It is imperative to carry out research on residual plastic film collection technology to solve the serious problem of farmland pollution. The residual plastic film baler was designed as a package for film strip collection, cleaning and baling. The collection device is a core component of the baler. Response surface analysis was used in this study to optimize the structure and working parameters for improving the collection efficiency of residual film and the impurity of film package. The results show that the factors affecting the collection rate of residual film and the impurity of the film package are the speed ratio ( ) between the trash removal roller and eccentric collection mechanism, the number ( ) and the mounting angle ( ) of spring teeth in the same revolution plane. For the collection rate, the importance of the three factors are in the order, . Meanwhile, for the impurity, the importance of three factors are in the order, . When the speed ratio, the mounting angle and the number of spring teeth was set at 1.6°, 45°, and 8°, respectively, the collection rate of residual film was 88.9% and the impurity of residual film package was 14.2% for the baler.

关键词： residual film     collection device     collection rate of residual film     impurity of film package     optimization     baler    

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甘肃省旱地农业技术创新与实践

郭贤仕,柳燕兰,候慧芝,郭天文

《中国工程科学》 2012年 第14卷 第3期   页码 65-69

摘要：

甘肃省地理跨度大，气候类型多种多样，旱地农业类型齐全，在长期的生产实践和科研活动中，把有效的传统抗旱办法与农田微集雨保墒工程、旱农耕作栽培技术、农业机械有机结合，创造了很多有区域特色的旱地农业技术。本文对甘肃省传统的砂田种植技术和旱地地膜小麦穴播技术、集雨农业技术体系进行简单回顾，对现阶段正在应用的主体创新旱农技术——全膜双垄沟播玉米、膜上覆土小麦种植技术体系的基本特点、抗旱增产机理及应用情况进行较详细的介绍。

关键词： 甘肃省     旱农技术创新     全膜双垄沟播玉米     膜上覆土小麦    

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Effects of mulching for water conservation on soil carbon, nitrogen and biological properties

Xiaomin PI, Tongxun ZHANG, Benhua SUN, Quanhong CUI, Yun GUO, Mingxia GAO, Hao FENG, David W. HOPKINS

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 146-154 doi: 10.15302/J-FASE-2017136

摘要： The effect of mulching with straw, white plastic film and black plastic film for improving soil water storage and on the soil properties was examined in a wheat-maize rotation system on Loess soil in northwestern China. All the mulches improved the water storage to some extent and led to warmer soils. However, the organic C and total N contents of the soils declined significantly under the mulches, particularly the plastic film mulches, and this could have long-term detrimental effects on soil quality and the sustainability of the some mulching practices.

关键词： biomass     carbon     mulch     nitrogen     plastic films     soil     straw     water storage    

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农用地膜污染防治战略研究

许咏梅, 房世杰, 马晓鹏, 朱倩倩

《中国工程科学》 2018年 第20卷 第5期   页码 96-102 doi: 10.15302/J-SSCAE-2018.05.015

摘要：

本文在分析我国农用地膜覆盖面积与使用量逐年加大、使用区域由西部向东部急速扩张特征的基础上，探讨了残膜污染态势、残膜造成的土壤理化性质恶化程度以及生态环境恶化风险。从普通聚乙烯地膜降解难且产品质量标准不达标、地膜回收困难再利用效率低、可降解地膜工艺不成熟、尚无可替代产品以及地膜污染缺乏监管机制四个方面梳理了地膜污染的成因。在此基础上，提出了加强地膜标准化生产控制，严格执行地膜厚度≥0.01 mm 的国家标准；优化地膜田间科学合理使用，开展作物适时揭膜技术推广；改进提高残膜回收机效能，努力实现地膜零残留；加大可降解地膜研发力度，推广可降解地膜田间应用的农用地膜防治战略，为我国农用地膜合理利用提供参考。

关键词： 农用地膜     污染态势     防治战略措施    

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Moving policy and regulation forward for single-use plastic alternatives

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1423-5

摘要： Single-use plastics are often used once or cannot be reused for extended periods. They are widely consumed with the rapid development of social economy. The waste generated by single-use plastics threatens ecosystem health by entering the environment and ultimately restricts sustainable human development. The innovation of sustainable and environmentally friendly single-use plastic alternative materials and the joint participation of governments, enterprises and the public are promising technologies and management approaches that can solve the problem of single-use plastics wastes. The development of single-use plastic alternative products can be promoted fundamentally only by improving relevant legislation and standards, providing differentiated industrial policies, encouraging scientific and technological innovation and expanding public participation.

关键词： Single-use plastic alternatives     Policy     Regulation     Sustainable development    

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Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 322-328 doi: 10.1007/s11705-012-1296-z

摘要： The objective of this study is to investigate numerically the flow characteristics of falling film on horizontal circular tubes. Numerical simulations are performed using FLUENT for 2D configurations with one and two cylinders. The volume of fluid method is used to track the motion of liquid falling film and the gas-liquid interface. The effect of flow characteristics on heat and transfer coefficient may be remarkable, although it has been neglected in previous studies. The velocity distribution and the film thickness characteristics on the top tube, some special flow characteristics on the bottom tube, intertube flow modes and effect of liquid feeder height on flow characteristics have been studied. Our simulations indicate that 1) the velocity distributions of the upper and lower parts of the tube are not strictly symmetric and non-uniform, 2) the film thickness depends on flow rate and angular distributions, 3) the flow characteristics of the top tube are different from those of the bottom tube, 4) three principal and two intermediate transition modes are distinguished, and 5) the liquid feed height plays an important role on the formation of falling film. The numerical results are in a good agreement with the theoretical values by the Nusselt model and the reported results.

关键词： falling film     horizontal tube     flow characteristics     film thickness     liquid feeder height    

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Current scenario and challenges of plastic pollution in Bangladesh: a focus on farmlands and terrestrial

《环境科学与工程前沿（英文）》 2023年 第17卷 第6期 doi: 10.1007/s11783-023-1666-4

摘要：

● A global snapshot of plastic waste generation and disposal is analysed.

关键词： Plastic waste     Farmlands     Terrestrial ecosystem     Marine life    

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Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

《农业科学与工程前沿（英文）》 2016年 第3卷 第2期   页码 161-170 doi: 10.15302/J-FASE-2016104

摘要： Mulching and soil water content (SWC) have a significant impact on soil erosion, and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China. Increasing initial SWC can decrease soil infiltration and increase soil loss. During an 80 mm rainfall event (80 mm·h for 60 min), 8%, 12% and 16% initial SWC treatments decreased cumulative infiltration by 8.7%, 42.5% and 58.1%, and increased total sediment yield by 44, 146 and 315 g, respectively, compared to 4% initial SWC. However, in all the straw mulching treatments, there was no significant difference in stable infiltration rate between the different initial SWC treatments. For all initial SWC treatments, straw mulching of 30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%, compared to the unmulched treatment. Taking into consideration the performance of no-till planters, a maize straw mulching rate of 30% to 60% (1400–3100 kg·hm ) is recommended for the conservation of water and soil in northern China.

关键词： infiltration     initial soil water content     rainfall simulation     soil loss     straw mulching    

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广义塑性力学及其运用

郑颖人,孔亮

《中国工程科学》 2005年 第7卷 第11期   页码 21-36

摘要：

分析了经典塑性力学用于岩土类材料的问题，它采用了3个不符合岩土材料变形机制的假设。从固体力学原理直接导出广义塑性位势理论，将经典塑性力学改造为更一般的塑性力学——广义塑性力学。广义塑性力学采用了塑性力学中的分量理论，能反映应力路径转折的影响，并避免了采用正交流动法则所引起的过大剪胀等不合理现象，也不会产生当前非关联流动法则中任意假定塑性势面引起的误差。给出了广义塑性力学的屈服面理论、硬化定律和应力-应变关系，并建立了考虑应力主轴旋转的广义塑性位势理论。屈服条件是状态参数，也是试验参数，只能由试验给出。应用表明，广义塑性力学可作为岩土材料的建模理论，还可应用于诸如极限分析等土力学的诸多领域，具有广阔的应用前景。

关键词： 岩土塑性力学     广义塑性力学     塑性势     屈服面     本构模型    

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薄膜润滑研究的回顾与展望

雒建斌,张朝辉,温诗铸

《中国工程科学》 2003年 第5卷 第7期   页码 84-89

摘要：

薄膜润滑是20世纪90年代以来广泛研究的新型润滑状态。它是界于弹流润滑和边界润滑之间的一种过渡润滑状态，有着自己独特的润滑规律。文章回顾了薄膜润滑的研究历史，包括薄膜润滑概念的提出、测试技术的发展、薄膜润滑的膜厚特性、润滑机理探索以及计算理论等方面的研究成果与主要进展。

关键词： 薄膜润滑     有序膜     膜厚测量     微结构    

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Thin-liquid-film evaporation at contact line

Hao WANG, Zhenai PAN, Zhao CHEN

《能源前沿（英文）》 2009年 第3卷 第2期   页码 141-151 doi: 10.1007/s11708-009-0020-2

摘要： When a liquid wets a solid wall, the extended meniscus near the contact line may be divided into three regions: a nonevaporating region, where the liquid is adsorbed on the wall; a transition region or thin-film region, where effects of long-range molecular forces (disjoining pressure) are felt; and an intrinsic meniscus region, where capillary forces dominate. The thin liquid film, with thickness from nanometers up to micrometers, covering the transition region and part of intrinsic meniscus, is gaining interest due to its high heat transfer rates. In this paper, a review was made of the researches on thin-liquid-film evaporation. The major characteristics of thin film, thin-film modeling based on continuum theory, simulations based on molecular dynamics, and thin-film profile and temperature measurements were summarized.

关键词： meniscus     thin film     contact line     disjoining pressure     evaporation    

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Effects of natural zeolite and sulfate ions on the mechanical properties and microstructure of plastic

《结构与土木工程前沿（英文）》 2022年 第16卷 第1期   页码 86-98 doi: 10.1007/s11709-021-0793-x

摘要： One of the strategic materials used in earth-fill embankment dams and in modifying and preventing groundwater flow is plastic concrete (PlC). PlC is comprised of aggregates, water, cement, and bentonite. Natural zeolite (NZ) is a relatively abundant mineral resource and in this research, the microstructure, unconfined strength, triaxial behavior, and permeability of PlC made with 0%, 10%, 15%, 20%, and 25% replacement of cement by NZ were studied. Specimens of PIC-NZ were subjected to confined conditions and three different confining pressures of 200, 350, and 500 kPa were used to investigate their mechanical behavior and permeability. To study the effect of sulfate ions on the properties of PlC-NZ specimens, the specimens were cured in one of two different environments: normal condition and in the presence of sulfate ions. Results showed that increasing the zeolite content decreases the unconfined strength, elastic modulus, and peak strength of PlC-NZ specimens at the early ages of curing. However, at the later ages, increasing the zeolite content increases unconfined strength as well as the peak strength and elastic modulus. Specimens cured in the presence of sulfate ions indicated lower permeability, higher unconfined strength, elastic modulus, and peak strength due to having lower porosity.

关键词： plastic concrete     sulfate resistance     natural zeolite     triaxial compression test     SEM     permeability    

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标题 作者 时间 类型 操作

中国塑料薄膜覆盖农业

陈奇恩

期刊论文

Quantification of pesticide residues on plastic mulching films in typical farmlands of the North China

Baoyuan Guo, Jiao Meng, Xinyu Wang, Chengnan Yin, Weiyu Hao, Baiwen Ma, Zhang Tao

期刊论文

Modeling water and heat transfer in soil-plant-atmosphere continuum applied to maize growth under plasticfilm mulching

Meng DUAN, Jin XIE, Xiaomin MAO

期刊论文

Experiment and optimal design of a collection device for a residual plastic film baler

Qi NIU,Xuegeng CHEN,Chao JI,Jie WU

期刊论文

甘肃省旱地农业技术创新与实践

郭贤仕,柳燕兰,候慧芝,郭天文

期刊论文

Effects of mulching for water conservation on soil carbon, nitrogen and biological properties

Xiaomin PI, Tongxun ZHANG, Benhua SUN, Quanhong CUI, Yun GUO, Mingxia GAO, Hao FENG, David W. HOPKINS

期刊论文

农用地膜污染防治战略研究

许咏梅, 房世杰, 马晓鹏, 朱倩倩

期刊论文

Moving policy and regulation forward for single-use plastic alternatives

期刊论文

Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

期刊论文

Current scenario and challenges of plastic pollution in Bangladesh: a focus on farmlands and terrestrial

期刊论文

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

期刊论文

广义塑性力学及其运用

郑颖人,孔亮

期刊论文

薄膜润滑研究的回顾与展望

雒建斌,张朝辉,温诗铸

期刊论文

Thin-liquid-film evaporation at contact line

Hao WANG, Zhenai PAN, Zhao CHEN

期刊论文

Effects of natural zeolite and sulfate ions on the mechanical properties and microstructure of plastic

期刊论文