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Effects of Nitrogen Application Levels on Ammonia Volatilization and Nitrogen Utilization during Rice Growing Season

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Rice science 2012年第2期19卷 125-134页

作者： LIN Zhong-cheng DAI Qi-gen YE Shi-chao WU Fu-guan JIA Yu-shu CHEN Jing-dou XU Lu-sheng ZHANG Hong-cheng Huo Zhong-yang Xu Ke wet hai-yan Key Laboratory of Crop Genetics and Physiology of Jiangsu Province / Innovation Center of Rice Cultivation Technology in yangtze Valley Ministry of Agriculture Yangzhou University Yangzhou 225009 China Agriculture Committee of Wujiang County Jiangsu Province Wujiang 215200 China Agriculture Bureau of Guannan County Jiangsu Province Guannan 222500 China

We conducted field trials of rice grown in sandy soil and clay soil to determine the effects of nitrogen application levels on the concentration of NH4＋-N in surface water, loss of ammonia through volatilization from paddy fields, rice production, nitrogen-use efficiency, and nitrogen content in the soil profile. The concentration of NH4＋-N in surface water and the amount of ammonia lost through volatilization increased with increasing nitrogen application level, and peaked at 1-3 d after nitrogen application. Less ammonia was lost via volatilization from clay soil than from sandy soil. The amounts of ammonia lost via volatilization after nitrogen application differed depending on the stage when it was applied, from the highest loss to the lowest： N application to promote tillering 〉 the first N topdressing to promote panicle initiation （applied at the last 4-leaf stage）〉 basal fertilizer 〉 the second N topdressing to promote panicle initiation （applied at the last 2-leaf stage）. The total loss of ammonia via volatilization from clay soil was 10.49-87.06 kg/hm2, equivalent to 10.92%-21.76% of the nitrogen applied. The total loss of ammonia via volatilization from sandy soil was 11.32-102.43 kg/hm2, equivalent to 11.32%-25.61 % of the nitrogen applied. The amount of ammonia lost via volatilization and the concentration of NH4＋-N in surface water peaked simultaneously after nitrogen application; both showed maxima at the tillering stage with the ratio between them ranging from 23.76% to 33.65%. With the increase in nitrogen application level, rice production and nitrogen accumulation in plants increased, but nitrogen-use efficiency decreased. Rice production and nitrogen accumulation in plants were slightly higher in clay soil than in sandy soil. In the soil, the nitrogen content was the lowest at a depth of 40-50 cm. In any specific soil layer, the soil nitrogen content increased with increasing nitrogen application level, and the soil nitrogen content was higher in

关键词： ammonia volatilization nitrogen application level soil type nitrogen-use efficiency rice

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Analysis of Micromechanical Properties at the Interface of Pre-wet SBS Modified Asphalt Mixture Based on Molecular Simulation Technology

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 103-113页

作者： CHEN Wuxing CHEN Shuang YU yan ZHANG Jiangyi XU haiyang GUO Wei School of Mines China University of Mining and TechnologyXuzhou 221000China College of Construction Engineering Jilin Uni-versityChangchun 130026China

The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and *** effect of pre-wetting technology on the interaction between SBS modified asphalt and aggregate was analyzed by molecular dynamics *** diffusion coefficient and concentration distribution of SBS modified asphalt on aggregate surface are *** simulation results show that the diffusion coefficient of the aggregate surface of SBS modified asphalt is increased by 47.6%and 70.5%respectively after 110#asphalt and 130#asphalt are *** concentration distribution of SBS modified asphalt on the aggregate surface after pre-wetting is more *** to the results of interface energy calculation,the interface energy of SBS modified bitumen and aggregate can be increased by about 5%after *** to the results of molecular dynamics simulation,the pre-wetting technology can effectively improve the interface workability of SBS modified bitumen and aggregate,so as to improve the interface performance.

关键词： pre-wet oil-stone interface interface interaction interface mechanics molecular dynamics simulation

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Estimation of irrigation requirements for drip-irrigated maize in a sub-humid climate

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Journal of Integrative Agriculture 2018年第3期17卷 677-692页

作者： LIU yang yanG hai-shun LI Jiu-sheng LI yan-feng yan hai-jun College of Water Resources and Civil Engineering China Agricultural University Beijing 100083 P.R.China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100048 P.R.China Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln 68503 United States

Drip-irrigation is increasingly applied in maize （Zea mays L.） production in sub-humid region. It is cdtical to quantify irrigation requirements during different growth stages under diverse climatic conditions. In this study, the Hybrid-Maize model was calibrated and applied in a sub-humid Heilongjiang Province in Northeast China to estimate irrigation requirements for drip- irrigated maize during different crop physiological development stages and under diverse agro-climatic conditions. Using dimensionless scales, the whole growing season of maize was divided into diverse development stages from planting to maturity. Drip-irrigation dates and irrigation amounts in each irrigation event were simulated and summarized in 30-year simulation from 1981 to 2010. The maize harvest area of Heilongjiang Province was divided into 10 agro-climatic zones based on growing degree days, arid index, and temperature seasonality. The simulated results indicated that seasonal irrigation requirements and water stress during different growth stages were highly related to initial soil water content and distribution of seasonal precipitation. In the experimental site, the average irrigation amounts and times ranged from 48 to 150 mm with initial soil water content decreasing from 100 to 20% of the maximum soil available water. Additionally, the earliest drip-irrigation event might occur during 3- to 8-leaf stage. The water stress could occur at any growth stages of maize, even in wet years with abundant total seasonal rainfall but poor distribution. And over 50% of grain yield loss could be caused by extended water stress during the kernel setting window and grain filling period. It is estimated that more than 94% of the maize harvested area in Heilongjiang Province needs to be irrigated although the yield increase varied （0 to 109%） in diverse agro-climatic zones. Consequently, at least 14% of more maize production could be achieved through drip-irrigation systems in Heilongjiang Provinc

关键词： drip irrigation irrigation requirements maize agro-climatic regionlization crop simulation sub-humid climate

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Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in Climate Change Research 2024年第3期15卷 442-451页

作者： Jian-Sheng HAO yan WANG Lan-hai LI Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China

Climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1967 to *** results reveal that the temperature increased significantly by 0.32°C per decade(pwet *** the risks of these events increase,they pose greater threats to farmlands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： Climate change Snowpack variations Snow-related disaster Tianshan Mountains

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An efficient dynamic uniform Cartesian grid system for inundation modeling

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Water Science and Engineering 2017年第4期10卷 267-274页

作者： Jing-ming Hou Run Wang hai-xiao Jing Xia Zhang Qiu-hua Liang yan-yan Di Institute of Water Resources and Hydro-Electric Engineering Xi'an University of Technology School of Civil Engineering and Geosciences Newcastle University Hydrology Bureau Yellow River Conservancy Commission

A dynamic uniform Cartesian grid system was developed in order to reduce the computational time in inundation simulation using a Godunov-type finite volume scheme. The reduction is achieved by excluding redundant dry cells, which cannot be effectively avoided with a conventional Cartesian uniform grid system, as the wet area is unknown before computation. The new grid system expands dynamically with wetting, through addition of new cells according to moving wet-dry fronts. The new grid system is straightforward in implementation. Its application in a field-scale flood simulation shows that the new grid system is able to produce the same results as the conventional grid, but the computational efficiency is fairly improved.

关键词： Uniform Cartesian grid system Flood simulation wetting and drying Shallow watere quation Godunov-type finite volume scheme

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Optimizing the drying parameters of a fixed bed with reversing ventilation for peanut using computer simulation

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 255-266页

作者： Jianchun yan Huanxiong Xie hai Wei Huichang Wu Zhaoyan You Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China

To obtain the optimal operation parameters of fixed-bed reversing ventilation drying of peanuts,a set of partial differential equations indicating the heat and mass transfer relationships between the peanut pods and air during drying was ***,a series of discretized models were established for simulation,and the time consumed,unevenness,and energy consumption for batch drying were *** results showed that reversing ventilation and segmented drying was helpful to these issues for high drying *** optimal operation parameters were determined by uniform design experimentation of mathematical *** result showed that when the moisture content(wet basis)was above 22%,a ventilation velocity of 0.46 m/s was optimal;when the moisture content was between 8%and 22%,a ventilation velocity of 0.20 m/s was *** the optimal parameters,the computer simulating result was compared with the experimental *** correlation coefficients between the simulating and the experimental values for the temperature and moisture content were all above 0.98 and the quality of dried peanuts was close to that of natural sun-dried ones,which indicates that the optimization results of the drying parameters are highly reliable.

关键词： peanut fix bed drying reversing ventilation simulation optimization

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Sangxingtang inhibits the inflammation of LPS-induced acute lung injury in mice by down-regulating the MAPK/NF-κB pathway

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Chinese Journal of Natural Medicines 2015年第12期13卷 889-895页

作者： ZHANG Tian-Zhu yanG Shi-hai YAO Jin-Fu DU Juan yan Tian-hua School of Pharmaceutical Sciences Changchun University of Chinese Medicine College of Chinese Medicinal Materials Jilin Agricultural University School of Life Science Peking University Department of Physiology and Pharmacology China Pharmaceutical University

In the present study, we investigated anti-inflammatory effects of Sangxingtang(SXT) on acute lung injury using a lipopolysaccharide(LPS)-induced acute lung injury(ALI) mouse model. The cell counting in the bronchoalveolar lavage fluid(BALF) was performed. The degree of lung edema was evaluated by measuring the wet/dry weight(W/D) ratio. The superoxidase dismutase(SOD) and myeloperoxidase(MPO) activities were assayed by SOD and MPO kits, respectively. The levels of inflammatory mediators, including tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6), were assayed by the enzyme-linked immunosorbent assay methods. Pathological changes of lung tissues were observed by Hematoxylin and eosin(HE) staining. The inflammatory signaling pathway-related proteins nuclear factor mitogen activated protein kinases(P38MAPK), extracellular regulated protein kinases(Erk), c-Jun N-terminal kinase(Jnk) and nuclear transcription factor(NF-κB) p65 expressions were measured by Western blotting. Our results showed that the treatment with the SXT markedly attenuated the inflammatory cell numbers in the BALF, decreased the levels of P-P38 MAPK, P-Erk, P-Jnk and P-NF-κB p65 and the total protein levels in lungs, improved the SOD activity and inhibited the MPO activity. Histological studies demonstrated that SXT substantially reduced the LPS-induced neutrophils in lung tissues, compared with the untreated LPS group. In conclusion, our results indicated that SXT had protective effects on LPS-induced ALI in mice.

关键词： Sangxingtang Inflammation LPS-induced acute lung injury MAPK/NF-κB pathway

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Tracing environmental lead sources on the Ao mountain of China using lead isotopic composition and biomonitoring

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Journal of Mountain Science 2017年第7期14卷 1358-1372页

作者： XIANG Zhong-xiang BING hai-jian WU yan-hong ZHOU Jun LI Rui HE Xiao-li The Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Atmospheric lead （Pb） and other trace metals can transport over long distance and deposit on remote alpine ecosystems. In this work, the soil profiles, litter and dominant mosses along a large altitude were collected on Ao Mountain, Central China, to obtain the spatial distributions of Pb in these materials, decipher the possible factors controlling the distribution, and quantitatively distinguish the natural versus anthropogenic sources of Pb through the Pb isotopic tracing and biomonitoring. The results show that soil Pb concentrations （mg/kg） decreased significantly with depth, and they were markedly higher in the 0 （42.6 ＋ 2.7） and A （36.4 ＋ 2.2） horizons than in the litter （7.20 ~ 1.9） and mosses （28.o ~ 3-9）- The Pb enrichment in the surface soils （0 and A horizons）, litter and mosses existed in the relatively high altitudes, which was attributed to the influences from atmospheric wet deposition, plants, soil Dhvsicochemical DroDerties and human activitv. ThePb isotopic ratios identified the Pb sources as originating mainly from Chinese coal combustion, mining and smelting. Atmospheric Pb from southeastern, southwestern and northwestern regions could be deposited in the alpine ecosystem by long distance atmospheric transport. The anthropogenic Pb reached over 50% in the 0 and A horizons, and over 70% in the litter and mosses, which corresponded to the concentrations of 26.9, 17.7, 5.92 and 21.2 mg/kg, respectively. The results indicate that the mutual effects of climate and regional human activity could increase the Pb accumulation in remote alpine ecosystems.

关键词： Source identification Pb isotope Biomonitoring Mountain soils Qinling region

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Effects of Chai-Qin-Cheng-Qi Decoction on cefotaxime in rats with acute necrotizing pancreatitis

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World Journal of Gastroenterology 2009年第35期15卷 4439-4443页

作者： Li-Hui Deng Da-Kai Xiang Ping Xue hai-yan Zhang Lei Huang Qing Xia Department of Integrated TraditionalChinese and Western Medicine West China Hospital SichuanUniversity Chengdu 610041 Sichuan Province China

AIM:To investigate the effect of Chai-Qin-Cheng-Qi Decoction(CQCQD)on cefotaxime(CTX)concentration in pancreas of rats with acute necrotizing pancreatitis (ANP). METHODS:Sixty healthy male Sprague-Dawley rats were divided randomly into an ANP group(ANP model +CTX,n=20),treatment group(ANP model+CTX +CQCQD,n=20)and control group(normal rats+ CTX,n=20).ANP models were induced by retrograde intraductal injection of 3.5%sodium taurocholate (1 mL/kg),and the control group was injected intraductally with normal *** rats were injected introperitoneally with 0.42 g/kg CTX(at 12-h intervals for a continuous 72 h)at 6 h after intraductal injection. Meanwhile,the treatment group received CQCQD (20 mL/kg)intragastrically at 8-h intervals,and the ANP and control group were treated intragastrically with normal *** 15 min after the last CTX injection,blood and pancreas samples were collected for the determination of CTX concentration using validated high-performance liquid chromatography. Pathological changes and wet-to-dry-weight(W/D) ratio of pancreatic tissue were examined. RESULTS:Serum CTX concentrations in three groups were not significantly *** CTXconcentration and penetration ratio were lower in ANP group vs control group(4.4±0.6μg/mL vs 18.6± 1.7μg/mL,P=0.000;5%vs 19%,P=0.000),but significantly higher in treatment group vs ANP group (6.4±1.7μg/mL vs 4.4±0.6μg/mL,P=0.020;7% vs 5%,P=0.048).The histological scores and W/D ratio were significantly decreased in treatment group vs ANP and control group. CONCLUSION:CQCQD might have a promotive effect on CTX concentration in pancreatic tissues of rats with ANP.

关键词： Acute necrotizing pancreatitis Cefotaxime Chai Qin Cheng Qi Decoction Drug penetration Traditional Chinese medicine

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Effect of dry-wet cycles on dynamic properties and microstructures of sandstone:Experiments and modelling

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International Journal of Mining Science and Technology 2024年第5期34卷 655-679页

作者： hai Pu Qingyu Yi Andrey P.Jivkov Zhengfu Bian Weiqiang Chen Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Earth Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China Department of Solids and Structures School of EngineeringUniversity of ManchesterManchester M139PLUK School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Department of Civil and Environmental Engineering Rice UniversityHouston 77005USA State Key Laboratory of High Performance Civil Engineering Materials Jiangsu Research Institute of Building Science Co.Ltd.Nanjing 210008China Department of Materials University of OxfordOxford OX13PHUK

Underground pumped storage power plant(UPSP)is an innovative concept for space recycling of abandoned *** realization requires better understanding of the dynamic performance and durability of reservoir *** paper conducted ultrasonic detection,split Hopkinson pressure bar(SHPB)impact,mercury intrusion porosimetry(MIP),and backscatter electron observation(BSE)tests to investigate the dynamical behaviour and microstructure of sandstone with cyclical dry-wet damage.A coupling FEM-DEM model was constructed for reappearing mesoscopic structure *** results show that dry-wet cycles decrease the dynamic compressive strength(DCS)with a maximum reduction of 39.40%,the elastic limit strength is reduced from 41.75 to 25.62 *** sieved fragments obtain the highest crack growth rate during the 23rd dry-wet cycle with a predictable life of 25 cycles for each rock *** pore fractal features of the macropores and micro-meso pores show great differences between the early and late cycles,which verifies the computational statistics analysis of particle *** numerical results show that the failure patterns are governed by the strain in pre-peak stage and the shear cracks are *** dry-wet cycles reduce the energy transfer efficiency and lead to the discretization of force chain and crack fields.

关键词： Underground pumped storage power plant Dry-wet cycles Split Hopkinson pressure bar Macro and micro properties FEM-DEM coupling model Damage characterization

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