检索结果-南通市图书馆

添加脲酶/硝化抑制剂条件下基于^(15)N示踪的夏玉米当季肥料氮去向研究

在线全文

学校读者我要写书评

暂无评论

植物营养与肥料学报 2024年第6期30卷 1092-1102页

作者：辛苏宁王磊卢艳丽白由路王玉红江晗王洛斌北方干旱半干旱耕地高效利用全国重点实验室/农业农村部植物营养与肥料重点实验室/中国农业科学院农业资源与农业区划研究所北京100081

【目的】以华北平原夏玉米为研究对象,利用高丰度15N同位素示踪方法,探究添加脲酶/硝化抑制剂条件下肥料氮的去向。【方法】于2022−06−25至2022−10−09在河北省廊坊市进行试验。设置5个处理:不施氮肥对照(CK)、单施尿素(U)、尿素+脲酶抑... 详细信息

【目的】以华北平原夏玉米为研究对象,利用高丰度15N同位素示踪方法,探究添加脲酶/硝化抑制剂条件下肥料氮的去向。【方法】于2022−06−25至2022−10−09在河北省廊坊市进行试验。设置5个处理:不施氮肥对照(CK)、单施尿素(U)、尿素+脲酶抑制剂(UI)、尿素+硝化抑制剂(NI)、尿素+脲酶抑制剂+硝化抑制剂(UI+NI),测定了氮素吸收量,监测了累积NH3挥发和N_(2)O排放量,并计算了肥料氮的气态损失量和土壤氮肥残留量。【结果】与单施尿素处理相比,3个添加抑制剂处理UI、NI和UI+NI的地上部吸氮量分别显著提高了39.7%、33.1%和41.8%,氮肥利用率分别显著提高12.5、6.8和12.3个百分点,UI和UI+NI的提升效果显著高于NI。与U和NI相比,UI处理的土壤中肥料氮残留量分别提高了35.6%和27.9%,UI+NI分别提高了45.7%和37.4%。与U处理相比,NI处理的NH3挥发累积量无显著差异,而UI和UI+NI处理土壤的NH3挥发累积量分别显著减少了14.3%和11.6%;UI、NI和UI+NI处理土壤的N_(2)O累积排放量分别显著降低了17.2%、19.9%和34.5%,UI+NI处理土壤的N_(2)O累积排放量又比UI和NI处理分别显著降低了20.9%和18.2%。【结论】尿素配合脲酶/硝化抑制剂施用显著提高了夏玉米的氮素吸收量,添加脲酶抑制剂显著提高了土壤中肥料氮残留量,减少了累积NH3挥发量和N_(2)O累积排放量,而添加硝化抑制剂增加土壤中肥料氮的残留量和减少NH3挥发的效果不显著,但降低了N_(2)O累积排放量。同时配施脲酶抑制剂和硝化抑制剂处理增加了土壤中肥料氮的残留量,降低NH3挥发量和N_(2)O累积排放量的效果显著优于配施一种抑制剂,肥料氮的损失率降至3.7%。因此,在华北平原典型潮土区,夏玉米生产中推荐尿素同时配施脲酶抑制剂和硝化抑制剂,以减少肥料氮的气态损失,提高氮肥当季利用率。

关键词：夏玉米高丰度15N尿素脲酶抑制剂硝化抑制剂氮肥当季吸收量土壤残留率气态损失肥料氮当季损失率

Effects of long-term full straw return on yield and potassium response in wheat-maize rotation

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2015年第12期14卷 2467-2476页

作者： BAI You-lu WANG Lei lu yan-li yanG li-ping ZHOU li-ping NI lu CHENG Ming-fang Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

The effect of long-term straw return on crop yield, soil potassium（K） content, soil organic matter, and crop response to K from both straw and chemical K fertilizer（K_2SO_4） were investigated in a fixed site field experiment for winter wheat-summer maize rotation in 6 years for 12 seasons. The field experiment was located in northern part of North China Plain with a sandy soil in relatively low yield potential. Two factors, straw return and chemical K fertilizer, were studied with two levels in each factor. Field split design was employed, with two straw treatments, full straw return of previous crop（St） and no straw return, in main plots, and two chemical K fertilizer treatments, 0 and 60 kg K2 O ha^（–1）, as sub-plots. The results showed that straw return significantly increased yields of winter wheat and summer maize by 16.5 and 13.2% in average, respectively, and the positive effect of straw return to crop yield showed more effective in lower yield season. Straw return significantly increased K absorption by the crops, with significant increase in straw part. In treatment with straw return, the K content in crop straw increased by 15.9 and 21.8% in wheat and maize, respectively, compared with no straw return treatment. But, straw return had little effect on K content in grain of the crops. Straw return had significant influences on total K uptake by wheat and maize plants, with an increase of 32.7 and 30.9%, respectively. There was a significant correlation between crop yield and K uptake by the plant. To produce 100 kg grain, the wheat and maize plants absorbed 3.26 and 2.24 kg K2 O, respectively. The contents of soil available K and soil organic matter were significantly affected by the straw return with an increase of 6.07 and 23.0%, respectively, compared to no straw return treatment. K_2SO_4 application in rate of 60 kg K2 O ha^（–1） showed no significant effect on wheat and maize yield, K content in crop straw, total K uptake by the crops, soil available K c

关键词： straw return potassium in straw wheat maize potassium response

Hyper-spectral characteristics and classification of farmland soil in northeast of China

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2015年第12期14卷 2521-2528页

作者： lu yan-li BAI You-lu yanG li-ping WANG Lei WANG Yi-lun NI lu ZHOU li-ping Key Laboratory of Crop Nutrition and Fertilization Ministry of AgricultureInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences

The physical and chemical heterogeneities of soils make the soil spectral different and complicated, and it is valuable to increase the accuracy of prediction models for soil organic matter（SOM） based on pre-classification. This experiment was conducted under a controllable environment, and different soil samples from northeast of China were measured using ASD2500 hyperspectral instrument. The results showed that there are different reflectances in different soil types. There are statistically significant correlation between SOM and reflectence at 0.05 and 0.01 levels in 550–850 nm, and all soil types get significant at 0.01 level in 650–750 nm. The results indicated that soil types of the northeast can be divided into three categories： The first category shows relatively flat and low reflectance in the entire band; the second shows that the spectral reflectance curve raises fastest in 460–610 nm band, the sharp increase in the slope, but uneven slope changes; the third category slowly uplifts in the visible band, and its slope in the visible band is obviously higher than the first category. Except for the classification by curve shapes of reflectance, principal component analysis is one more effective method to classify soil types. The first principal component includes 62.13–97.19% of spectral information and it mainly relates to the information in 560–600, 630–690 and 690–760 nm. The second mainly represents spectral information in 1 640–1 740, 2 050–2 120 and 2 200–2 300 nm. The samples with high OM are often in the left, and the others with low OM are in the right of the scatter plot（the first principal component is the horizontal axis and the second is the longitudinal axis）. Soil types in northeast of China can be classified effectively by those two principles; it is also a valuable reference to other soil in other areas.

关键词： soil type spectral characteristics principle component classification

Ultra-flexible all-in-one anti-freeze photothermally enhanced supercapacitors

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7221-7229页

作者： Yongxin lu Keke li yan-yan Song Zhida Gao Condense matter of physics College of ScienceNortheazistern UniversityShenyang 110004China

Wearable electronics powered by flexible energy storage devices have captured global *** low-temperature conditions,unfortunately,solidification of flexible hydrogel electrolyte and decreased pseudo-capacity of these devices largely hamper their practical *** this study,photothermally-active Prussian blue(PB)was introduced onto poly(3,4-ethylenedioxythiophene)/polyacrylamide(PEDOT/PAM)networks to address the challenges of electrolyte solidification and degraded pseudo-capacitance for flexible all-in-one device at low *** as-constructed PB/PEDOT/PAM hydrogel device delivers stable electrochemical performance and remarkable mechanical property with 1652%***,this hydrogel device well retains its flexibility in cold environment with a freezing point below−30℃.The incorporation of PB extends the voltage range to 1.5 V as a single device,thus significantly enhancing the electrochemical performance as an all-inone integrated *** from the outstanding photo-to-thermal conversion ability of embedded PB nanocubes,the temperature of the assembled all-in-one PB/PEDOT/PAM device increased from^(−2)0 to 17.7℃ after solar-light irradiation for only 5 ***,the degraded pseudo-capacitance was subsequently boosted to 287.1%of its original capacitance at−20℃.This study establishes a connection between flexible all-solid-state hydrogel devices and photothermally enhanced pseudocapacitors in freezing environments,thereby expanding the potential applications of multi-functional pseudo-capacitors.

关键词： all-in-one energy storage devices all-solid-state photothermal flexible low temperatures

Evaluation of standard liver volume formulae for Chinese adults

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第32期15卷 4062-4066页

作者： Zheng-Rong Shi lu-Nan yan Bo li Tian-Fu Wen liver Transplantation Division Department of Surgery West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

AIM:To evaluate different standard liver volume (SLV) formula and verify the applicability of the formulae for Chinese ***: Data from 70 cases of living donor liver transplantation (LDLT) performed at our transplantation centers between January 2008 and April 2009 were analyzed. SLV was estimated using our recently reported formula [the Chengdu formula: SLV (mL)=11.5×body weight (kg) + 334] and other reported formulae used for Chinese adults. Actual intraoperative liver volumes were obtained from a review of the patients' medical ***: The actual right liver volume was not significantly different from the estimated right liver volume determined by the Chengdu formula, but was significantly smaller than estimates using the Heinemann, Urata, Vauthey, and Lee formulae (PluSION: The Chengdu formula was demonstrated to be reliable by its application in LDLT.

关键词： Standard liver volume living donor livertransplantation Chinese adult liver volume formula

Microscopic Phase-Field Study of the Occupancy Probability of α Sublattices Involving Coordination Environmental Difference for D0_(22)-Ni_(3)V

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第2期29卷 155-158页

作者： ZHANG Jing CHEN Zheng ZHUANG Hou-Chuan lu yan-li State Key Laboratory of Solidification Processing School of Material Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072

The nickel sites of a D022-Ni3 V phase are subdivided into Ni1 and Ni2 sublattices according to their coordination sphere *** occupancy probability (OP) differences influenced by the coordination sphere are interpreted using the microscopic phase field *** OP of regular atoms (NiNi_(1),NiNi_(2)),antisite defects (VNi1,VNi2),and substitutional defects (AlNi_(2),AlNi_(1) ) have strong site preferences,as well as temperature-dependence features,on both *** features involve both redistribution of components,and phase transition from D0_(22) to L1_(2).

关键词： coordination phase Probability

A new nonfullerene acceptor with an extended π conjugation core enables ternary organic solar cells approaching 19%efficiency

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 4062-4068页

作者： Chunyan liu Nailiang Qiu Zhengjin li yan lu School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric DevicesMinistry of EducationTianjin University of TechnologyTianjin 300384China School of Chemistry Chemical Engineering and MaterialsJining UniversityQufu 273155China

In organic solar cells(OSCs),it is an effective way to improve the power conversion efficiency(PCE)by adding a guest component with appropriate absorption and energy levels in the host ***,a new nonfullerene acceptor(NFA)named TBF-2Cl was developed by the strategy of expanding theπconjugated core of 2,2’-(((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b’]dithiophene-2,7-diyl)bis(methaneylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(IDT-4Cl)with two benzene *** increase of benzene units,TBF-2Cl exhibits higher lowest unoccupied molecular orbital(luMO)level of-3.75 eV than that of one benzene unit based NFA IDT-4Cl and fluorene core based NFA F-2Cl,which facilitates enhancing the open-circuit voltage(V_(oc))of ternary ***,TBF-2Cl film shows a medium optical bandgap with the absorption range from 500-800 nm,being well complementary with the wide bandgap polymer donor D18 and narrow bandgap NFA ***,a remarkable PCE of 18.92%with a high short-circuit current density(J_(sc))of 27.40 mA·cm^(-2),a fill factor(FF)of 0.749,especially an outstanding V_(oc) of 0.922 V was achieved for the optimal ternary device based on D18:TBF-2Cl:CH-6F,surpassing the binary counterpart(17.08%).The findings provide insight into the development of new guest acceptors for obtaining more efficient OSCs.

关键词： medium optical bandgap high lowest unoccupied molecular orbital(luMO)level the third component ternary organic solar cell high open-circuit voltage

Development of Soil Crusts Under Simulated Rainfall and Crust Formation on a Loess Soil as Influenced by Polyacrylamide

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2012年第3期22卷 415-424页

作者： HU Xia liU lian-You li Shun-Jiang CAI Qiang-Guo lu yan-li GUO Jin-Rui State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875(China) Academy of Disaster Reduction and Emergency Management Beijing Normal UniversityBeijing 100875(China) Institute of Plant Nutrition and Resources Beijing Academy of Agriculture and Forestry SciencesBeijing 100097(China) Institute of Geographical Science and Natural Resources Research Chinese Academy of SciencesBeijing 100101(China)

This study evaluated the morphological characteristics and dynamic variation in characteristics of soil crust and iden-tified the relationships between soil crust and splash erosion under simulated *** effect of polyacrylamide (PAM) on soil aggregate stabilization and crust formation was also investigated.A laboratory rainfall simulation experiment was carried out using soil sample *** slices were examined under a polarized light microscopy and a scanning electron microscope (SEM).The results revealed that the soil crusts were thin and were characterized by a greater density,higher shear strength,finer porosity,and lower saturated hydraulic conductivity than the underlying *** types of crusts,i.e.,structural and depositional crusts,were *** texture was determined to be the most important soil variable influ-encing surface crust formation;depositional crust formation was primarily related to the skeleton characteristics of the soil and happened when the soil contained a high level of medium and large *** crust formation processes observed were as follows:1) The fine particles on the soil surface became spattered,leached,and then rough in response to raindrop impact and 2) the fine particles were washed into the subsoil pores while a compact dense layer concurrently formed at soil surface due to the continual compaction by the ***,the factors that influenced structural crust formation were a large amount of fine particles in the soil surface,continual impact of raindrops,dispersion of aggregates into fine particles,and the formation of a compact dense layer concurrently at the soil *** was concluded that the most important factor in the formation of soil crusts was raindrop *** polyacrylamide (PAM) was applied,it restored the soil structure and greatly increased soil aggregate *** effectively prevented crust ***,this function of PAM was not continuously effective and

关键词： depositional crust raindrop impact soil aggregates splash erosion structural crust

Random gradient-free method for online distributed optimization with strongly pseudoconvex cost functions

在线全文

学校读者我要写书评

暂无评论

Control Theory and Technology 2024年第1期22卷 14-24页

作者： Xiaoxi yan Cheng li Kaihong lu Hang Xu School of Electrical and Information Engineering Jiangsu UniversityZhenjiang212013JiangsuChina College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao266590ShandongChina

This paper focuses on the online distributed optimization problem based on multi-agent systems. In this problem, each agent can only access its own cost function and a convex set, and can only exchange local state information with its current neighbors through a time-varying digraph. In addition, the agents do not have access to the information about the current cost functions until decisions are made. Different from most existing works on online distributed optimization, here we consider the case where the cost functions are strongly pseudoconvex and real gradients of the cost functions are not available. To handle this problem, a random gradient-free online distributed algorithm involving the multi-point gradient estimator is proposed. Of particular interest is that under the proposed algorithm, each agent only uses the estimation information of gradients instead of the real gradient information to make decisions. The dynamic regret is employed to measure the proposed algorithm. We prove that if the cumulative deviation of the minimizer sequence grows within a certain rate, then the expectation of dynamic regret increases sublinearly. Finally, a simulation example is given to corroborate the validity of our results.

关键词： Multi-agent system Online distributed optimization Pseudoconvex optimization Random gradient-free method