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Journal of Integrative Agriculture 2016年第12期15卷 2848-2854页

作者： FANG Hui-min ZHANG Qing-yi JI Chang-ying GUO Jun College of Engineering Nanjing Agricultural University

Following a rice or wheat harvest, a large amount of crop residue （straw） is retained in fields. The straw is often incorporated into the soil in order to increase the soil organic carbon storage and to reduce soil erosion. However, it has become apparent that the incorporated straw can significantly alter soil shear properties, which can dramatically affect energy inputs for tilling and other soil management practices. In this study, laboratory-remolded wheat straw-soil samples were compared with field-collected straw-soil samples; we found high correlations for the cohesion （R2=0.9084） and internal friction angle （R2=0.9548） properties of the samples. Shear tests on rice and wheat straw with different moisture content levels clearly demonstrated the relatively higher shear strength of wheat straw compared to rice straw. The cohesion of remolded rice and wheat straw-soil samples exhibited an increasing linear trend with an increase in densities, whereas the internal friction angle data for these samples exhibited a quadratic trend. Overlapping the cohesion curves revealed that the wheat straw-soil and rice straw-soil samples had the same cohesion at a straw density of 0.63%. Similar results were obtained when the internal fraction angle curves overlapped; the resultant point of intersection was observed at a straw density of 0.46%. As a whole, the remolded sample methodology was found suitable to simulate the shear properties of soils sampled directly from fields.

关键词： direct shear test wheat straw rice straw cohesion internal friction angle

Utilization of discarded crop straw to produce cellulose nanofibrils and their assemblies

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Journal of Bioresources and Bioproducts 2020年第1期5卷 26-36页

作者： Xiaran Miao Jinyou Lin Fenggang Bian Shanghai Synchrotron Radiation Facility of Zhangjiang Lab Shanghai Advanced Research InstituteShanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China

A tremendous amount of wheat straw(WS)has been generated by wheat crops every year,while only a small percentage is being used in applications,and most get burned on the field,causing a large amount of the exhaust gas that pollutes the ***,we report on the extraction of cellulose nanofibrils(CNF)from the alkali treated WS by a combination of 2,2,6,6-tetramethylpyperidine-1-oxyl(TEMPO)-oxidation and mechanical disintegration *** crystalline structures,thermal properties,natural charge of the CNF were *** re-sultant nano-building blocks of the CNF was assembled into macroscopic cellulose materials,i.e.,film,aerogel,and filament in this ***,the morphologies and microstructues as well as other properties of these three kinds of the CNF assemblies were *** ob-tained CNF and its assemblies showed a potential application in new materials *** work explored a new way to utilize the discarded WS instead of being burned.

关键词： Cellulose Cellulose nanofibrils wheat straw Cellulose aerogels

Influence of Mechanical Grinding on the Interface Characteristics of Rice/wheat straws

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Journal of Agricultural Science and Technology(B) 2013年第5期3卷 369-376页

作者： Dingguo Zhou Peixing Wei College of Wood Science and Technology Nanjing Forestry University Nanjing 210037 China

The mechanical grinding method was used to make rice and wheat straw flakes and the properties of the interface of straws before and after grinding were evaluated. The particle boards were prepared using two kinds of straw flakes, respectively and their physical and mechanical properties were investigated. The results showed that the rice straw was easier to be broken when compared with wheat straw and the inner surface of cells in grinded straws was exposed remarkably. The characteristic peaks of lignin and cellulose on the surface of wheat straw were more significant than rice straw. The free-radical concentrations of straws were increased dramatically after being grinded with heating in the range from I00 ~C to 200 ~C. The surface free energy of straws was also improved after being grinded and the value in wheat straw was higher than that of rice straw, which implies that wheat straw was easier to be bonded than rice straw. The physical and mechanical properties of two kinds of straw particle boards could achieve the requirements of Chinese National Standards of GB 4897.3-2003, while wheat straw particle boards had better properties than those made from rice straws.

关键词： Rice straw wheat straw surface free radicals surface free energy mechanical grinding method.

Nitrous oxide emissions from a maize field during two consecutive growing seasons in the North China Plain

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Journal of Environmental Sciences 2012年第1期24卷 160-168页

作者： Yuanyuan Zhang Junfeng Liu Yujing Mu Zhu Xu Shuwei Pei Xiaoxiu Lun Ying Zhang Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Graduate School of Chinese Academy of Sciences Beijing 100039China College of Environmental Science and Engineering Beifing Forestry UniversityBeijing 100083China School of Economics and Management Beijing Forestry UniversityBeijing 100083China

Nitrous oxide （N 2 O） emissions from a maize field in the North China Plain （Wangdu County,Hebei Province,China） were investigated using static chambers during two consecutive maize growing seasons in the 2008 and *** N 2 O pulse emissions occurred with duration of about 10 days after basal and additional fertilizer applications in the both *** average N 2 O fluxes from the CK （control plot,without crop,fertilization and irrigation）,NP （chemical N fertilizer）,SN （wheat straw returning plus chemical N fertilizer）,OM- 1/2N （chicken manure plus half chemical N fertilizer） and OMN （chicken manure plus chemical N fertilizer） plots in 2008 were 8.51,72.1,76.6,101,107 ng N/（m 2 ·sec）,respectively,and in 2009 were 33.7,30.0 and 35.0 ng N/（m 2 ·sec） from CK,NP and SN plots,*** emission factors of the applied fertilizer as N 2 O-N （EFs） were 3.8% （2008） and 1.1% （2009） for the NP plot,3.2% （2008） and 1.2% （2009） for the SN plot,and 2.8% and 2.2% in 2008 for the OM-1/2N and OMN plots,*** properties of the investigated soil （with gley） are in favor of *** large differences of the soil temperature and water-filled pore space （WFPS） between the two maize seasons were suspected to be responsible for the significant yearly *** with the treatments of NP and SN,chicken manure coupled with compound fertilizer application significantly reduced fertilizer loss rate as N 2 O-N.

关键词： nitrous oxide fertilizers wheat straw manure maize field North China Plain

Effects of Biochar and Super Absorbent Polymer on Substrate Properties and Water Spinach Growth

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Pedosphere 2015年第5期25卷 737-748页

作者： FAN Ruqin LUO Jia YAN Shaohua ZHOU Yunlai ZHANG Zhenhua Institute of Agricultural Resources and Environment Jiangsu Academy of Agricultural Sciences School of Earth and Environment The University of Western Australia

Most previous researches have focused on biochar application in agricultural soils; however, limited information is available concerning the effects of biochar amendment on greenhouse substrate properties. A greenhouse experiment was conducted to investigate effects of wheat straw biochar （0-160 mL L-1） and super absorbent polymer （SAP, 0.8 g L-1） on physical and chemical properties of a substrate based on spent pig litter compost and the growth of water spinach （Ipomoea aquatica Forsk）. Total porosity, water-holding capacity~ pH and electrical conductivity （EC） of the substrate significantly increased with increasing biochar rates, especially in the substrate without SAP. The values of pH and EC were significantly lower in the substrate with SAP than those without SAP at the high biochar application rates （100-160 mL L-l）. The germination rates of water spinach decreased with increasing biochar rates when biochar was added alone （76.9%-83.7%）, whereas the rates increased to 83.6%-85.8% when biochar was added in combination with SAP. Growth parameters of water spinach and nutrient uptake by shoots and roots increased with increasing biochar rates and reached the maximum values at the biochar rate of 100 mL L-1. There were significant cubic relationships between the uptake of nutrients （N, P, and K） and biochar rates, both with and without SAP addition. In order to avoid negative effects on plant growth, the biochar application rate should be controlled at an optimal level （100 mL L-1 ）. The SAP addition not only enhanced the positive effects of biochar application on the properties of the substrate, but also inhibited the excessive rise of pH and EC following biochar additions, which led to better plant growth and enhanced nutrient uptakes by water spinach.

关键词： amendment electrical conductivity nutrient uptake pH total porosity water-holding capacity water spinach wheat straw

Factors affecting the quality of biomass pellet for biofuel and energy analysis of pelleting process

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International Journal of Agricultural and Biological Engineering 2013年第2期6卷 1-12页

作者： Phani K.Adapa Lope G.Tabil Greg J.Schoenau Department of Chemical and Biological Engineering University of SaskatchewanSaskatoonS7N 5A9 SKCanada Department of Mechanical Engineering University of SaskatchewanSaskatoonS7N 5A9 SKCanada

Agricultural biomass residue such as barley,canola,oat and wheat straw has the potential to be used for sustainable production of bio-fuels and offset greenhouse gas *** biomass substrate must be processed and handled in an efficient manner in order to reduce industry’s operational cost as well as meet the requirement of raw material for biofuel *** has low bulk density,making it difficult and costly to store and transport in its native loose ***,in this study,an integrated approach to densification of non-treated and steam exploded barley,canola,oat and wheat straw was *** this process,the significance of major contributing factors(independent variables such as biomass type,treatment,pressure and grind size)on pellet density,durability and specific energy were *** has been found that applied pressure(60.4%)was the most significant factor affecting pellet density followed by the application of steam explosion pre-treatment(39.4%)for lab-scale single pelleting ***,the type of biomass(47.1%)is the most significant factor affecting durability followed by the application of pre-treatment(38.2%)and grind size(14.6%)for pellets manufactured using the pilot-scale pellet ***,applied pressure(58.3%)was the most significant factor affecting specific energy required to manufacture pellets followed by the biomass(15.3%),pre-treatment(13.3%)and grind size(13.2%),which had lower but similar effect on specific energy for lab-scale single pelleting *** energy analysis of post-harvest processing and densification of agricultural straw was performed,which showed that a significant portion of original agricultural biomass energy(89%-94%)is available for the production of ***,similar amount of specific energy is required to produce pellets from barley,canola,oat and wheat straw *** pellets having steam exploded straw required more energy to manufacture resulting

关键词： biofuel biomass steam explosion pretreatment pelleting specific energy barley straw canola straw oat straw wheat straw

Improving antioxidant activities of water-soluble lignin-carbohydrate complex isolated from wheat stalk through prolonging ball-milling pretreatment and homogeneous extraction

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Journal of Bioresources and Bioproducts 2024年第1期9卷 113-125页

作者： Di Xie Zhulan Liu Yunfeng Cao Sheng-I Yang Chen Su Mi Li Jiangsu Co-innovation Center for Efficient Processing and Utilization of Forest Products Nanjing Forestry UniversityNanjing 210037China International Innovation Center for Forest Chemicals and Materials Nanjing Forestry UniversityNanjing 210037China Center for Renewable Carbon School of Natural ResourcesUniversity of TennesseeKnoxvilleTN 37996USA Shandong Huatai Paper Co. Ltd.Dongying 257000China School of Natural Resources University of TennesseeKnoxvilleTN 37996USA Key Lab of Biomass Energy and Material Institute of Chemical Industry of Forest ProductsChinese Academy of ForestryJiangsu ProvinceNanjing 210042China

Water-soluble lignin-carbohydrate complex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and ***,the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still ***,structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations(4,6,8 h),extraction pathways(ho-mogeneous and heterogeneous),and isolation routines(water extracts and residues after water extraction).Their structures were characterized by wet chemistry,chromatography and *** activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate(RDPPH).Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble ***,prolonging ball-milling duration to 8 hours and homogeneous extrac-tion can enhance their antioxidant activity through releasing more phenolic structures and pro-moting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance,*** a result,the RDPPH of water-soluble LCCs reaches up to 97.35%,which is associated with the arabinan content with statistical significance(P<0.05).This study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.

关键词： LCC Homogeneous extraction Ball-milling Structure-antioxidation relationship wheat straw

Developing More Effective Enhanced Biochar Fertilisers for Improvement of Pepper Yield and Quality

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Pedosphere 2015年第5期25卷 703-712页

作者： YAO Chunxue Stephen JOSEPH LI Lianqing PAN Genxing Yun LIN Paul MUNROE Ben PACE Sarasadat TAHERYMOOSAVI Lukas VAN ZWIETEN Torsten THOMAS Shaun NIELSEN Jun YE Scott DONNE Institute of Resources Ecosystem and Environment of Agriculture Nanjing Agricultural University Discipline of Chemistry University of Newcastle School of Materials Science and Engineering University of New South Wales New South Wales Department of Primary Industries School of Biotechnology and Biomolecular Sciences & Centre for Marine Bio-Innovation University of New South Wales

Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1 may not return a profit to the farmer due to the high cost of biochar. In this study biochar was modified through pre-treating the biomass and post-treating with phosphoric acid, minerals and different chemical fertilisers to study the effects of two new enhanced biochar fertilisers on the yield and quality of green pepper in a field experiment with 5 fertilisation treatments and 3 replications. The two new biochar fertilisers significantly （P 〈 0.05） increased the yield of green pepper （11.33-11.47 t ha-l）, compared with the conventional chemical fertiliser （9.72 t ha-l）. The biochar fertiliser treatments improved the vitamin C content of green pepper from 236.99 to 278.28 mg kg-1, and also significantly （P 〈 0.05） reduced the nitrate content from 132.32 to 101.92 mg kg-1, compared with chemical fertiliser. This study indicated that, compared to the use of conventional chemical fertiliser, all of the biochar fertiliser treatments could significantly improve the yield and quality of green pepper.

关键词： bentonite clay chemical fertiliser nitrate content phosphoric acid vitamin C content wheat straw

MECHANICAL PROPERTIES OF straw/POLYSTYRENE COMPOSITE

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MECHANICAL PROPERTIES OF STRAW/POLYSTYRENE COMPOSITE

Microbial Biomass Dynamics in a Tropical Agroecosystem： Influence of Herbicide and Soil Amendments

作者： Xu Min, Li Yuhong, Wang Keqi, Jiang Xiaobing Material Science and Engineering College, Northeast Forestry University, Harbin 150040, China

＜正＞The wheat straw/polystyrene composite was prepared by hot-pressing wheat straw and recycled Polystyrene （PS）. Orthogonal experiments and Single-factor experiments were conducted to study the effects of press cycle time, temperature, composite density, PS proportion, and resin content on the properties of wheat straw/PS composite. The results showed that when hot pressing recycle time was 7 minutes, temperature was 190℃, PS proportion was 35% , resin content was 3% . density was 0. 6 g/cm3 and 0. 65 g/cm3, the mechanical properties of the composite met the requirement of Chinese National Standard （GB/T4897. 14897. 7-2003）. The study confirmed the optimal process parameters.

关键词： wheat straw Polystyrene Composite Mechanical Property

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Pedosphere 2016年第2期26卷 257-264页

作者： Alka SINGH Mahesh Kumar SINGH Nandita GHOSHAL Centre of Advanced Study in Botany Department of Botany Banaras Hindu University Varanasi 221005 India

The influences of herbicide alone and in combination with the soil amendments with contrasting resource qualities on dynamics of soil microbial biomass C （MBC）, N （MBN）, and P （MBP） were studied through two annual cycles in rice-wheat-summer fallow crop sequence in a tropical dryland agroecosystem. The experiment included application of herbicide （butachlor） alone or in combination with various soil amendments having equivalent amount of N in the forms of chemical fertilizer, wheat straw, Sesbania aculeata, and farm yard manure （FYM）. Soil microbial biomass showed distinct temporal variations in both crop cycles, decreased from vegetative to grain-forming stage, and then increased to maximum at crop maturity stage. Soil MBC was the highest in herbicide ＋ Sesbania aculeata treatment followed by herbicide ＋ FYM, herbicide ＋ wheat straw, herbicide ＋ chemical fertilizer, and herbicide alone treatments in decreasing order during the rice-growing period. During wheat-growing period and summer fallow, soil MBC attained maximum for herbicide ＋ wheat straw treatment whereas herbicide ＋ FYM, herbicide ＋ Sesbania, and herbicide ＋ chemical fertilizer treatments showed similar levels. The overall trend of soil MBN was similar to those of soil MBC and MBP except that soil MBN was higher in herbicide ＋ chemical fertilizer treatment over the herbicide ＋ wheat straw treatment during rice-growing period. In spite of the addition of equivalent amount of N through exogenous soil amendments in combination with the herbicide, soil microbial biomass responded differentially to the treatments. The resource quality of the amendments had more pronounced impact on the dynamics of soil microbial biomass, which may have implications for long-term sustainability of rainfed agroecosystems in dry tropics.

关键词： chemical fertilizer farmyard manure organic amendment Sesbania aculeata wheat straw