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Fate of fertilizer nitrogen and residual nitrogen in paddy soil in Northeast China

Journal of Integrative Agriculture 2023年第11期22卷 3535-3548页

作者： bi shi-ting LUO Xiang-yu ZHANG Chen LI Peng-fei YU Cai-lian LIU Zhi-lei PENG Xian-long College of Agricultural Resources and Environmental Sciences Northeast Agricultural UniversityHarbin 150030P.R.China Key Laboratory of Germplasm Enhancement Physiology and Ecology of Food Crops in Cold Region of Ministry of EducationNortheast Agricultural UniversityHarbin 150030P.R.China The School of Material Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150080P.R.China

The relationship between the fate of nitrogen (N) fertilizer and the N application rate in paddy fields in Northeast China is unclear,as is the fate of residual *** clarify these issues,paddy field and15N microplot experiments were carried out in 2017 and 2018,with N applications at five levels:0,75,105,135 and 165 kg N ha–1(N0,N75,N105,N135 and N165,respectively).15N-labeled urea was applied to the microplots in 2017,and the same amount of unlabeled urea was applied in *** (NH3) volatilization,leaching,surface runoff,rice yield,the N contents and15N abundances of both plants and soil were *** results indicated a linear platform model for rice yield and the application rate of N fertilizer,and the optimal rate was 135 kg N ha–1.N uptake increased with an increasing N rate,and the recovery efficiency of applied N (REN) values of the difference subtraction method were 45.23 and 56.98%on average in 2017and 2018,*** RENwas the highest at the N rate of 135 kg ha–1in 2017 and it was insignificantly affected by the N application rate in 2018,while the agronomic efficiency of applied N (AEN) and physiological efficiency of applied N (PEN) decreased significantly when excessive N was applied.N loss through NH3volatilization,leaching and surface runoff was low in the paddy fields in Northeast ***3volatilization accounted for 0.81 and 2.99%of the total N application in 2017 and 2018,*** average,the leaching and surface runoff rates were 4.45% and less than 1.05%,respectively,but the apparent denitrification loss was approximately 42.63%.The residual N fertilizer in the soil layer (0–40 cm) was 18.37–31.81 kg N ha–1in 2017,and the residual rate was 19.28–24.50%.Residual15N from fertilizer in the soil increased significantly with increasing N fertilizer,which was mainly concentrated in the 0–10 cm soil layer,accounting for 58.45–83.54% of the total residual N,and decreased with increasing *** the ratio of residual N in the

关键词： fate of N fertilizer NH_(3) volatilization leaching surface runoff residual nitrogen yield

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考虑退绕问题的刚性航天器全局姿态稳定性控制

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电机与控制学报 2017年第7期21卷 94-98页

作者：毕显婷史小平哈尔滨工业大学控制与仿真中心黑龙江哈尔滨150080

针对刚性航天器姿态机动问题设计了能够有效减小能量损耗的非线性状态反馈控制器。由于修正罗德里格斯参数(modified rodrigues parameter,MRP)原始集在特征轴旋转角为±360°时存在奇异点,而相应的MRP映射集(shadow set)的奇异点处于... 详细信息

针对刚性航天器姿态机动问题设计了能够有效减小能量损耗的非线性状态反馈控制器。由于修正罗德里格斯参数(modified rodrigues parameter,MRP)原始集在特征轴旋转角为±360°时存在奇异点,而相应的MRP映射集(shadow set)的奇异点处于特征轴旋转角为0°。将MRP原始集与映射集结合起来,实现全局非奇异姿态描述,解决了航天器姿态控制中的退绕(unwinding)问题。利用平方和(SOS)方法设计非线性状态反馈控制律,实现航天器全局姿态渐近稳定控制,同时实现更短控制路径,保证了控制过程中特征轴旋转角|Φ|≤180°。仿真结果表明了在干扰条件下该控制方法可有效控制航天器姿态稳定,且对能量损耗给出了定量分析结果。

关键词：平方和法 MRP映射集全局渐近稳定退绕问题

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Robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 154-168页

作者： Fei Weng Guijun bi Youxiang Chew Shang Sui Chaolin Tan Zhenglin Du Jinlong Su Fern Lan Ng Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong Engineering&Technology Research Center for Superhard MaterialSchool of Materials Science and EngineeringShandong UniversityJinan 250061China Institute of Intelligent Manufacturing Guangdong Academy of SciencesGuangzhou 510095China Singapore Institute of Manufacturing Technology 5 Cleantech Loop636732Singapore

The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for LAAM_(p) and LAAM_(w),*** the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire *** characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α *** mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and *** mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material Specifications(AMS 6932)even without post heat *** fracture occurred within the interfacial area,further suggesting the robust *** findings of this study highlighted the feasibility of combining LAAM_(p) and LAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition.

关键词： laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior

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Effect of bi/Si Ratio of biBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 13-24页

作者： LIU Wei JIAO Jinxu LUO Dusha ZHOU Junjie shi Lifen WANG Weiwei LI Changqing WANG Peng XIONG Dehua LI Hong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China

The low-melting glass of bi2O_(3)-B2O_(3)-SiO_(2)(biBSi)system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

关键词： bi2O_(3)-B2O_(3)-SiO_(2)(biBSi) bi/Si ratio low-melting glass laser sealing vacuum glazing

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Photosynthetic reaction pathways of natural and artificial systems

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Science China Chemistry 2025年

作者： shixing Lei Liting bi Lingxuan Chen Zhanting Li Jia Tian State Key Laboratory of Organometallic Chemistry and Shanghai Hong Kong Joint Laboratory in Chemical Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences

Photosynthesis converts solar energy into chemical energy through highly coordinated photosynthetic *** by natural systems,artificial photosynthesis aims to develop an efficient,sustainable,and cost-effective pathway for solar-tochemical *** review examines natural photosynthetic pathways,including retinal/rhodopsin-,bacteriochlorophyll-,and chlorophyll-based systems,highlighting their key components and ***,we outline reaction pathways in artificial photosynthetic systems constructed via heterogeneous,homogeneous,self-assembly,and semi-artificial strategies,focusing on water splitting,carbon fixation,and nitrogen ***,we offer insights into future directions for artificial photosynthesis,emphasizing the importance of using self-assembly strategies and the potential of using primitive phototrophic microorganisms as models.

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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats

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Neural Regeneration Research 2025年第4期20卷 1164-1177页

作者： Pengfei Wang Yuewei bi Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang Neurosurgery Center Department of Pediatric NeurosurgeryGuangdong Provincial Key Laboratory on Brain Function Repair and RegenerationZhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Long-term levodopa administration can lead to the development of levodopa-induced *** oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced ***,studies have reported increased oscillation power in cases of levodopa-induced ***,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced ***,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is *** found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s ***,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma *** of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum ***,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum *** findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia.

关键词： aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials neuromodulation Parkinson’s disease primary motor cortex

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养分调控与栽培模式对大豆干物质积累及产量的影响

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大豆科学 2016年第4期35卷 593-598页

作者：韩利萍孙磊田静儇张泽钰邰枫毕诗婷刘元英东北农业大学资源与环境学院黑龙江哈尔滨150030

本研究以垦农23为试验材料,探讨养分调控与栽培模式对大豆干物质积累及产量的影响。采用二因素裂区试验设计,主区为养分调控处理,设置优化施肥(D)和对照施肥(N)2个水平;副区为栽培模式处理,在130 cm的大垄上分别设置垄上4行、垄上5行和... 详细信息

本研究以垦农23为试验材料,探讨养分调控与栽培模式对大豆干物质积累及产量的影响。采用二因素裂区试验设计,主区为养分调控处理,设置优化施肥(D)和对照施肥(N)2个水平;副区为栽培模式处理,在130 cm的大垄上分别设置垄上4行、垄上5行和垄上6行3种模式。结果表明:大豆生育期内叶面积指数和干物质积累过程均呈单峰曲线,其峰值出现在结荚期至鼓粒盛期之间。鼓粒期干物质积累与产量呈极显著正相关。优化施肥(D)处理通过提高叶面积指数和干物质积累量,在不同栽培模式下的产量均高于对照施肥(N)处理,其中D-4比N-4提高4.3%,D-5比N-5提高17.1%,D-6比N-6提高29.5%。本试验条件下,优化施肥技术与130 cm垄上6行栽培模式,在34万株·hm-2的种植密度下是当地大豆高产优质合理种植模式。

关键词：大豆养分调控栽培模式干物质积累产量

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不同烫漂方式及冷冻速率对预制西兰花质构品质的影响

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食品科学 2025年第1期46卷 121-130页

作者：赵伊诺金鑫毕金峰谢意通杜婷天津科技大学食品科学与工程学院天津300457 中国农业科学院农产品加工研究所农业农村部农产品加工重点实验室北京100193 沈阳农业大学食品学院辽宁沈阳110866

为探究预制西兰花加工过程中烫漂方式及冷冻速率对西兰花质构品质的影响,对经2种烫漂方式(热水烫漂、蒸汽烫漂)及3种冷冻温度(-20、-40、-80℃)处理的西兰花样品,利用低场核磁共振、理化特性分析方法测定不同处理组样品的水分分布、持... 详细信息

为探究预制西兰花加工过程中烫漂方式及冷冻速率对西兰花质构品质的影响,对经2种烫漂方式(热水烫漂、蒸汽烫漂)及3种冷冻温度(-20、-40、-80℃)处理的西兰花样品,利用低场核磁共振、理化特性分析方法测定不同处理组样品的水分分布、持水性、相对电导率和硬度,观察微观结构。结果表明:维持西兰花硬度的最佳工艺为蒸汽烫漂后进行-40℃冷冻,在此工艺条件下,与对照组相比,处理组西兰花水分分布中结合水峰面积占比(A21)增加最多、持水性最强,花序部分保留66.72%硬度、茎部分保留62.53%硬度,相对电导率增加至87.01%;通过扫描电子显微镜观察发现,经过该处理的西兰花保持了较好的细胞结构。本研究得到了有效维持解冻西兰花质构的工艺,并揭示了不同处理对西兰花水分分布及细胞膜完整性影响的机制,为实际生产过程保持冷冻预制西兰花品质提供了理论与技术支撑。

关键词：预制西兰花持水性水分迁移质构

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Attitude stabilization of rigid spacecraft implemented in backstepping control with input delay

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Journal of Systems Engineering and Electronics 2017年第5期28卷 955-962页

作者： Xianting bi Xiaoping shi Control and Simulation Center Harbin Institute of Technology

A backstepping method is used for nonlinear spacecraft attitude stabilization in the presence of external disturbances and time delay induced by the actuator. The kinematic model is established based on modified Rodrigues parameters (MRPs). Firstly, we get the desired angular velocity virtually drives the attitude parameters to origin, and then backstep it to the desired control torque required for stabilization. Considering the time delay induced by the actuator, the control torque functions only after the delayed time, therefore time compensation is needed in the controller. Stability analysis of the close-loop system is given afterwards. The infinite dimensional actuator state is modeled with a first-order hyperbolic partial differential equation (PDE), the L-2 norm of the system state is constructed and is proved to be exponentially stable. An inverse optimality theorem is also employed during controller design. Simulation results illustrate the efficiency of the proposed control law and it is robust to bounded external disturbances and time delay mismatch.

关键词： backstepping input delay partial differential equation (PDE) inverse optimality

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Iterative parameter estimate with batched binary-valued observations

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Science China(Information Sciences) 2016年第5期59卷 158-175页

作者： Yanlong ZHAO Wenjian bi ting WANG Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, we consider linear system identification with batched binary-valued *** constructed an iterative parameter estimate algorithm to achieve the maximum likelihood(ML) *** first interesting result was that there exists at most one finite ML solution for this specific maximum likelihood problem, which was induced by the fact that the Hessian matrix of the log-likelihood function was negative definite under binary data and Gaussian system noises. The global concave property and local strongly concave property of the log-likelihood function were obtained. Under mild conditions on the system input, we proved that the ML function has a unique maximum point. The second main result was that the ML estimate was consistent under persistent excitation inputs, which infers the effectiveness of ML estimate. Finally, the proposed iterative estimate algorithm converged to a fixed vector with an exponential rate that was proved by constructing a Lyapunov function. A more interesting result was that the limit of the iterative algorithm achieved the maximization of the ML function. Numerical simulations are illustrated to support the theoretical results obtained in this paper well.

关键词： binary-valued observation maximum likelihood estimate strongly convex system identification exponential rate

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