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Responses of Agronomic Benefit and Soil Quality to Better Management of Nitrogen Fertilizer Application in Greenhouse Vegetable Land

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Pedosphere 2012年第5期22卷 650-660页

作者： JIANG hui-Min ZHANG Jian-Feng song Xiao-Zong LIU zhao-hui JIANG Li-Hua YANG Jun-Cheng Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081(China) Institute of Agricultural Resources and Environment Shandong Academy of Agricultural SciencesJinan 250100(China)

As a result of intensive greenhouse vegetable production in northern China, the potential risk of nitrogen （N） fertilizer over-applied is increasingly apparent and is threatening ecosystem and the sustainability of food production. An experiment was carried out in Shouguang, Shangdong Province, China to evaluate agronomic benefit and soil quality under different N applications, including the conventional chemical N rate （1000 kg N ha^（-1） season^（-1）, N1）, 70% of N1 （N2）, 70% of N1 ＋ maize straw （N3）, 50% of N1 ＋ maize straw ＋ drip irrigation （N4）, and 0% of N1 （NO）, during two successive growing seasons of autumn-winter （AW） and winter-spring （WS）. The maximum yields for N4 were 1.1 and 1.0 times greater than those for N1 in the AW and WS seasons, respectively. N agronomic efficiency （AEN） and apparent N recovery efficiency （REN） were greatest with the N4. A significant relationship was found between soil NO3-N content and electrical conductivity （EC）（R^2 = 0.61 in the AW season and R^2= 0.29 in the WS season）. Reducing N fertilizer decreased soil NO3-N accumulation （20.9%-37.8% reduction in the AW season and 11.7%-20.1% reduction in the WS season） relative to the accumulation observed for N1 within the 0-100 cm soil layer. Soil urease and invertase activities were not significantly different among N treatments. The N4 treatment would be practical for reducing excess N input and maintaining the sustainability of greenhouse-based intensive vegetable systems in Shouguang.

关键词： maize straw N use efficiency soil enzyme soil NO3-N accumulation tomato yields

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Studies on Rheological, Thermal, and Mechanical Properties of Polylactide/Methyl Methacrylate-Butadiene-Styrene Copolymer/Poly(propylene carbonate) Polyurethane Ternary Blends

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Chinese Journal of Polymer Science 2019年第12期37卷 1273-1282,I0007页

作者： Ji-Li zhao Hong-Wei Pan hui-Li Yang Jun-Jia Bian hui-Liang Zhang Ge Gao Li-song Dong College of Chemistry Jilin UniversityChangchun 130012China Department of Science Beihua UniversityJilin 132013China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Zhejiang Zhongke Applied Chemistry Technology Co. Ltd.Hangzhou 310000China

Polylactide(PLA),methyl methacrylate-butadiene-styrene copolymer(MBS),and poly(propylene carbonate)polyurethane(PPCU)were blended and subjected to blown film *** rheological,mechanical,morphological,thermal,and crystalline properties of the PLA/MBS/PPCU ternary blends and the mechanical properties of the resulting films were *** of mechanical test showed that PPCU and MBS could synergistically toughen *** impact strength of 50/10/40 PLA/MBS/PPCU blend(74.7 k J/m^2)was about 7.5 times higher than that of the neat PLA(10.8 k J/m^2),and the elongation at break of 50/10/40 PLA/MBS/PPCU blend(276.5%)was higher by about 45 times that of PLA(6.2%).The tear strength of PLA/MBS/PPCU films was 20 k N/m higher than that of PLA,and the elongation at break(MD/TD)of 50/10/40 PLA/MBS/PPCU films was 271.1%/222.3%,whereas that of PLA was only 2.7%/3.0%.POM observations displayed that the density of spherulite nucleation increased and the size of crystalline particles decreased with the addition of *** increasing PPCU content from 5%to 20%,the density of spherulite nucleation increased and the size of crystalline particles decreased continuously,but the nucleation density of spherulites was slightly lowered with increasing PPCU content from 30%to 40%.The PLA/MBS/PPCU films exhibited excellent mechanical properties,which expanded the application range of these biodegradable films.

关键词： Biodegradable Polylactide Poly(propylene carbonate)polyurethane Methyl methacrylate-butadiene-styrene copolymer Films

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Efficient elimination and detection of phenolic compounds in juice using laccase mimicking nanozymes

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Chinese Journal of Chemical Engineering 2021年第1期34卷 167-175页

作者： hui Huang Lulu Lei Juan Bai Ling Zhang Donghui song Jingqi zhao Jiali Li Yongxin Li College of Food Science and Engineering Jilin UniversityChangchun 130025China College of New Energy and Environment Jilin UniversityChangchun 130021China

Residual phenols in the juice can cause turbidity and affect its sensory *** is used to remove phenolic compounds from fruit juice *** order to overcome the shortcomings of natural laccase instability and high cost,in this work,we prepared a laccase mimic enzyme based on copper ion and adenosine monophosphate(AMP-Cu nanozymes).At the same mass concentration(1 mg·ml^(-1)), the catalytic activity of the nanozyme is about 15 times that of *** AMP-Cu nanozymes had a higher V_(max) and a lower Km than *** laccase mimic enzyme had a good stability under the condition of 30-90 ℃ and pH> *** also maintained high catalytic activity at high salt concentrations and 9 days storage ***,the AMP-Cu nanozyme s maintained an initial catalytic activity of about 80% after six consecutive cycles of *** linear range of detection of phenolic compounds by AMP-Cu nanozymes was 0.1-100 μmol·L^(-1) with a detection limit of 0.033 μmol·L^(-1).The phenol removal rate of AMP-Cu nanozymes was much higher than that of laccase under different reaction *** the reaction was performed for 5 h,the phenol removal rate of the fruit juice by AMP-Cu nanozymes was about 65%.The efficient removal of phenolic compounds from different juices by AMP-Cu nanozymes indicate s that they have good application prospect in the food juice industry.

关键词： Nanomaterials Enzyme Mimic laccase Phenols detection Degradation Juice clarification

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Noninvasive beam diagnosis based on the TM_(010)mode

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Nuclear Science and Techniques 2024年第7期35卷 115-125页

作者： Chuang-Ye song Wen-hui Huang Department of Engineering Physics Tsinghua University BeijingBeijing100084China of Education Beijing100084China

A resonant cavity based on the TM_(010)mode is an effective tool for noninvasive beam characterization. This technique has the advantages of a high signal-to-noise ratio, compact structure, and is related to multiple parameters compared with other beam monitors. In this study, high-precision measurements of the bunch charge, arrival time, bunch length, and energy parameters based on the TM_(010)mode are discussed. A cavity beam arrival time monitor(BAM) utilizing a phase cavity has been widely used in many facilities. Regarding bunch-length measurements, the influence of the beam energy, beam offset,and longitudinal spectrum on the TM_(010)mode are carefully considered to reduce errors, and the theoretical resolution of two cavities with different frequencies is analyzed. Owing to the dependence of the beam velocity of the beam loss factor, this method can also be used for the detection low beam energy using two cavities with the same frequency but different cavity lengths. A set of three cavities with different lengths and frequencies of 1.902 and 11.424 GHz is presented for measuring the four aforementioned parameters.

关键词： TM_(010)mode Noninvasive diagnosis Beam length Low energy

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Compressed sensing method for human activity recognition using tri-axis accelerometer on mobile phone

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The Journal of China Universities of Posts and Telecommunications 2017年第2期24卷 31-37,71页

作者： song hui Wang Zhongmin School of Computer Science and Technology Xi'an University of Posts and Telecommunications

The diversity in the phone placements of different mobile users＇ dailylife increases the difficulty of recognizing human activities by using mobile phone accelerometer data. To solve this problem, a compressed sensing method to recognize human activities that is based on compressed sensing theory and utilizes both raw mobile phone accelerometer data and phone placement information is proposed. First, an over-complete dictionary matrix is constructed using sufficient raw tri-axis acceleration data labeled with phone placement information. Then, the sparse coefficient is evaluated for the samples that need to be tested by resolving L1 minimization. Finally, residual values are calculated and the minimum value is selected as the indicator to obtain the recognition results. Experimental results show that this method can achieve a recognition accuracy reaching 89.86%, which is higher than that of a recognition method that does not adopt the phone placement information for the recognition process. The recognition accuracy of the proposed method is effective and satisfactory.

关键词： activity recognition compressed sensing mobile phone accelerometer phone placements

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EFFECT OF DAMAGE EVOLUTION ON POISSON'S RATIO OF CONCRETE UNDER SULFATE ATTACK

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Acta Mechanica Solida Sinica 2011年第3期24卷 209-215页

作者： hui song Jiankang Chen The Faculty of Mechanical Engineering and Mechanics Ningbo University Ningbo 315211 China State Key Laboratory of Turbulence and Complex Systems Peking University Beijing 100871 China

Experimental results about concrete under sulfate attack are summarized, which include the variation of mass density of samples and velocity of ultrasonic wave propagating in samples. The evolution damage is analyzed in terms of the experimental results, and close attention is paid to the effect of damage evolution on Poisson＇s ratio. This study shows that Poisson＇s ratio is significantly affected by the concentration of solution and water-cement ratio. Poisson＇s ratio of concrete changes very little when the water-cement ratio is selected as 0.6 or 0.8, so that such change may be neglected. If water-cement is 0.4, however, the Poisson＇s ratio of the sample significantly changes. When the concrete sample of 0.4 water-cement ratio is immersed in sodium sulfate solution of 8% concentration for 285 days, Poisson＇s ratio increase 10.14% compared with its initial value. There exist a sensitive region and a non-sensitive region for the change rate of Poisson＇s ratio with respect to corrosion time. The change rate of Poisson＇s ratio monotonously decreases with corrosion time in the sensitive region; in the non-sensitive region, the change rate of Poisson＇s ratio is almost equal to zero.

关键词： concrete sulfate attack porosity Poisson's ratio damage evolution

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Inferring diffusion networks with life stage heterogeneity

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Science China(Information Sciences) 2018年第9期61卷 5-20页

作者： Tong zhao Guojie song Xinran HE Key Laboratory of Machine Perception (MOE) Peking University Computer Science Department University of Southern California

A network inference problem focuses on discovering the structure of a diffusion network from observed cascades. This problem is significantly more challenging in several settings in which this type of an inference is desirable or necessary because of heterogeneity in the diffusion process. The heterogeneity of the diffusion process in different life stages results in the inaccuracy of a common assumption of constant influence strength. In this study, a Life Stage Heuristic(LSH) method is proposed to model life stage heterogeneity by decoupling the popularity level of an item under propagation from a true strength of social ties to improve inference accuracy. The proposed LSH is incorporated into almost all existing state-of-the-art network inference algorithms to improve estimation accuracy with only minimal changes in the implementation and maintaining the same running time. Additionally, Net Rate, Net Inf, and Con NIe are used as three examples to demonstrate the power of the proposed method. Furthermore, clustering of cascades prior to the LSH is proposed to eliminate noise, and the optimized method is termed as Clustered Life Stage Heuristic(CLSH).Extensive experiments on synthetic and real world datasets indicate that both LSH and CLSH methods significantly improve the accuracy of network inference.

关键词： network inference life stage heterogeneity social influence information diffusion clustering cascade

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Influence of Cu content on the mechanical properties and corrosion resistance of Mg-Zn-Ca bulk metallic glasses

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 487-493页

作者： Yan-feng zhao Jian Zhu Li Chang Jing-guo song Xiao-hua Chen Xi-dong hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

（***28.8Cas）10o-xCux （at%, x = 0, 1, 3, and 5） bulk metallic glasses （BMGs） of 2 mm in diameter were prepared by the conventional copper mold injection casting method. Besides, the influence of Cu content on the microstructure, thermal stability, mechanical properties, and corrosion behavior of Mg-Zn--Ca BMGs was investigated. It is found that the addition of Cu decreases the glass-forming ability of Mg-Zn-Ca BMGs. Crystalline phases are precipitated at a higher Cu content, larger than 3at%. The compressive fracture strength of Mg-Zn-Ca BMGs is enhanced by the addition of Cu. With the formation of in-situ composites, the compressive strength of the Mg-Zn-Ca alloy with 3at% Cu reaches 979 MPa, which is the highest strength among the Mg-Zn-Ca alloys. Furthermore, the addition of Cu also results in the increase of corrosion potential and the decrease of corrosion current density in Mg-Zn-Ca BMGs, thereby delaying their biodegradability.

关键词： metallic glass glass-forming ability compressive strength corrosion thermal stability

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Evaluation of capabilities of ultrasonic energy on failure load and corrosion resistance of friction stir lap welded Al-steel joints

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Journal of Iron and Steel Research International 2024年第10期31卷 2489-2504页

作者： Tao Liu song Gao Lei Shi Sachin Kumar Zhi-ping Sun Wei zhao hui Zhang Ning Guo School of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250300ShandongChina Shandong Institute of Mechanical Design and Research Jinan250300ShandongChina Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(MOE) Shandong UniversityJinan250061ShandongChina Department of Mechanical Engineering Indian Institute of Information Technology Design and Manufacturing(IIITDM)JabalpurMadhya Pradesh482005India

The lap joints of 6061-T6 aluminum alloy/Q235 steel were prepared by conventional friction stir welding and ultrasonic vibration enhanced friction stir ***,the effect of ultrasonic vibration on the microstructure and properties of joints was analyzed,and then the optimization mechanism of ultrasonic vibration on failure load and corrosion resistance of joints was *** results indicated that ultrasonic vibration could significantly improve the quality of weld formation,expand the width of interface zone,change the shape of the“hook”structure,form a macro mechanical interlock at the joint interface,and effectively refine the grain structure on the steel *** terms of the microstructure of the joints,additional ultrasonic energy can change the microstructure characteristics at the interface,and can improve the distribution characteristics of precipitates in the weld nugget zone,significantly reducing the number of intermetallic compounds generated across the interface of the retreating side and forming micro mechanical interlock on the advancing side of the *** ultrasonic treatment,the failure load of the aluminum/steel lap joint increased by 20.4%,and the corrosion resistance improved by 1.304 times.

关键词： Friction stir welding Ultrasonic vibration Aluminum/steel heterogeneous component Failure load Corrosion resistance

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Quantum Discord Behavior about Two-Qubit Heisenberg XYZ Model with Decoherence

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Chinese Physics Letters 2014年第3期31卷 18-22页

作者： song Le YANG Guo-hui School of Physics and Information Engineering Shanxi Normal University Linfen 041004

We investigate the properties of quantum discord dynamics of a two-qubit Heisenberg XYZ system which is influenced by the environmental decoherence under an external nonuniform magnetic field. It shows that the influence of the parameters on the system heavily rely on the selection of the initial states. One point shows that the environmental decoherence cannot entirely destroy the quantum correlation, and properly controlling the parameters can inhibit the decoherence. Moreover, it presents that the inhomogeneous magnetic field cannot affect the steady quantum discord （QD）, while the uniform magnetic field and the anisotropy coupling constant will change the steady QD. These investigations imply that one can obtain larger steady QD values by reasonably adjusting parameters on quantum correlation in solid state systems.

关键词： Magnetic fields

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