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Effects of reducing and postponing controlled-release urea application on soil nitrogen regulation and maize grain yield

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International Journal of Agricultural and Biological Engineering 2022年第1期15卷 116-123页

作者： Pengtao Ji Yujuan Peng yongwei cui Xiangling Li Peijun Tao Yuechen Zhang College of Agronomy Hebei Agricultural University/State Key Laboratory of North China Crop Improvement and RegulationBaoding 071001HebeiChina Academy of Agricultural Planning and Engineering Ministry of Agriculture and Rural AffairsBeijing 100125China College of Agronomy and Biotechnology Hebei Normal University of Science&Technology/Hebei Key Laboratory of Crop Stress BiologyQinhuangdao 066004HebeiChina

Controlled-release urea(CRU-N)fertilizer application is a solution to improve the utilization rate of nitrogen(N),reduces economic costs and improves crop yields.It is significant to study the effects of release CRU-N reduction and the combined application of conventional urea on soil N control and the large-scale maize planting system.In this study,the effects of controlled-release nitrogen fertilizer reduction and postponement on soil nitrogen components,enzyme activities,and yields were investigated.Seven treatments were set up in this study,including no N fertilizer(CK),100%conventional urea(U),100%controlled-release urea(S),30%controlled-release urea(SU_(3/7)),50%controlled-release urea(SU_(5/5)),70%controlled-release urea(SU_(7/3))and Sodium Salt of Polyaspartic Acid(PASP)-N.The results showed that mixed CRU-N and urea increased yields and net benefits compared with conventional urea at the same application rate of N,and reduced N loss.The application of CRU-N at 70%for maize represented the best overall effects.Compared with U treatment,soil ammonium nitrogen(NH_(4)-N),soil nitrate-nitrogen(NO_(3)-N),and microbial biomass nitrogen(SMB-N)of CRU-N at 70%(SU_(7/3))increased by 35.00%,15.53%,and 25.04%.However,soil nitrate reductase(S-NR)and urease(S-UA)were the best in SU_(5/5) and significantly higher than other treatments.The applications of CRU-N would effectively increase soil N;CRU-N in 50%proportion can promote the maize root growth and improve the efficient utilization of N by soil microorganisms.Like the yields(9186.61 kg/hm^(2)),expertly in the proportion of 70%CRU-N(SU_(7/3))plays a vital role in a wheat-maize rotation system,which can potentially be used to improve the yields,nitrogen use efficiency,and net benefit with low N losses.In conclusion,using CRU-N fertilize effectively improves soil nitrogen,and various ratios of CRU-N can ensure the continuous release the nutrients during the growing period.And among the different proportions of CRU-N,it is optimal in SU_(7/3).

关键词： controlled-release urea nitrogen regulation maize grain yield soil reducing postponing

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Soil physical properties,nutrients,and crop yield with two-year tillage rotations under a winter wheat-summer maize double cropping system

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International Journal of Agricultural and Biological Engineering 2022年第1期15卷 172-181页

作者： Baozhong Yin Pan Liu yongwei cui Zhaohui Hu Xiangling Li Zhihua Pan Wenchao Zhen College of Resources and Environment Sciences China Agricultural UniversityBeijing 100193China College of Plant Protection Hebei Agricultural UniversityBaoding 071001HebeiChina State Key Laboratory of North China Crop Improvement and Regulation Baoding 071001HebeiChina College of Agronomy Hebei Agricultural UniversityBaoding 071001HebeiChina Academy of Agricultural Planning and Engineering Ministry of Agriculture and Rural AffairsBeijing 100125China College of Life Science Hebei Agricultural UniversityBaoding 071001HebeiChina Hebei Normal University of Science and Technology Qinhuangdao 066000HebeiChina Key Laboratory of Crop Growth Regulation of Hebei Province Baoding 071001HebeiChina

Winter wheat and summer maize were planted from 2015-2017 to study the effects of different rotational tillage patterns on soil physicochemical properties,crop yield,water content,and fertilizer utilization.The tillage treatments were designed as wheat subsoiling-maize no tillage(WS-MN),wheat rotary tillage-maize subsoiling(WR-MS),wheat subsoiling-maize subsoiling(WS-MS),and conventional wheat rotary tillage-maize no tillage(WR-MN)as a control.Among the four treatments,WS-MN and WR-MS were single-season subsoiling treatments,and WS-MS was a two-season subsoiling treatment.The average soil bulk density decreased by 7.6%in the single-and double-season subsoiling groups compared to the WR-MN group,and the total porosity and noncapillary porosity increased by 10.7%and 12.2%,respectively.Single-or double-season subsoiling treatment was not conducive to water storage in the 0-20 cm soil layer but increased the water content of the 20-140 cm soil layer,and the average soil water content of the 0-140 cm layer was increased by 11.6%in the two-growing season treatment groups compared with the WR-MN group.In WS-MS and WS-MN groups compared with the WR-MN group,the soil ammonium nitrogen content was increased by an average of 18.6%in 0-20 cm soil and 16.8%in 20-100 cm soil;soil nitrate-nitrogen content was decreased by 13.5%in 0-100 cm soil;total organic carbon and microbial carbon contents in the 15-30 cm soil were increased by 18.1%and 12.7%,respectively;and soil urease,catalase,and alkaline phosphatase activities were increased by 46.1%,15.2%,and 23.1%,respectively.Annual crop yield and water use efficiency increased by 8.9%and 15.0%,respectively,in both the single-and double-season subsoiling treatment groups.This study demonstrated the advantages of subsoiling tillage and suggested that it is suitable for crop cultivation in the Haihe Plain,China.

关键词： tillage rotations wheat-maize double cropping soil properties utilization of water and fertilizer crop yield

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Nonrelativistic and nonmagnetic terahertz-wave generation via ultrafast current control in anisotropic conductive heterostructures

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Advanced Photonics 2023年第5期5卷 86-95页

作者： Sheng Zhang yongwei cui Shunjia Wang Haoran Chen Yaxin Liu Wentao Qin Tongyang Guan Chuanshan Tian Zhe Yuan Lei Zhou Yizheng Wu Zhensheng Tao Fudan University State Key Laboratory of Surface PhysicsDepartment of PhysicsShanghaiChina Fudan University Key Laboratory of Micro and Nano Photonic StructuresShanghaiChina Shanghai Research Center for Quantum Sciences ShanghaiChina Beijing Normal University Center for Advanced Quantum StudiesDepartment of PhysicsBeijingChina Fudan University Institute for Nanoelectronic Devices and Quantum ComputingShanghaiChina

Precise and ultrafast control over photo-induced charge currents across nanoscale interfaces could lead to important applications in energy harvesting,ultrafast electronics,and coherent terahertz sources.Recent studies have shown that several relativistic mechanisms,including inverse spin-Hall effect,inverse Rashba–Edelstein effect,and inverse spin-orbit-torque effect,can convert longitudinally injected spinpolarized currents from magnetic materials to transverse charge currents,thereby harnessing these currents for terahertz generation.However,these mechanisms typically require external magnetic fields and exhibit limitations in terms of spin-polarization rates and efficiencies of relativistic spin-to-charge conversion.We present a nonrelativistic and nonmagnetic mechanism that directly utilizes the photoexcited high-density charge currents across the interface.We demonstrate that the electrical anisotropy of conductive oxides RuO2 and IrO2 can effectively deflect injected charge currents to the transverse direction,resulting in efficient and broadband terahertz radiation.Importantly,this mechanism has the potential to offer much higher conversion efficiency compared to previous methods,as conductive materials with large electrical anisotropy are readily available,whereas further increasing the spin-Hall angle of heavy-metal materials would be challenging.Our findings offer exciting possibilities for directly utilizing these photoexcited high-density currents across metallic interfaces for ultrafast electronics and terahertz spectroscopy.

关键词： terahertz optics ultrafast science nanophotonics

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基于四元驱动的非平稳水文干旱评估方法

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水资源保护 2024年第1期40卷 71-78页

作者：崔豪江善虎任立良朱永卫杜树平严登华河海大学水灾害防御全国重点实验室江苏南京210098 河海大学水文水资源学院江苏南京210098 中国水利水电科学研究院水资源研究所北京100038

为了科学评估自然-社会系统影响下非平稳水文干旱,考虑气候变化(降水、气温)和人类活动(取用水、水库)四元要素的影响,通过基于四元驱动的GAMLSS模型构建非平稳标准化径流指数(NSRI),提出了基于四元驱动的非平稳水文干旱评估方法。黄河... 详细信息

为了科学评估自然-社会系统影响下非平稳水文干旱,考虑气候变化(降水、气温)和人类活动(取用水、水库)四元要素的影响,通过基于四元驱动的GAMLSS模型构建非平稳标准化径流指数(NSRI),提出了基于四元驱动的非平稳水文干旱评估方法。黄河流域非平稳水文干旱实例评估结果表明:黄河流域花园口站径流序列呈现出明显的非平稳特征,径流量1961—2020年发生显著下降,并在1990年发生突变;基于四元驱动的非平稳水文干旱评估方法能够更好地对径流数据进行非平稳概率分布拟合;对于历史干旱事件的识别,NSRI识别的干旱过程与实际更加接近,NSRI比标准化径流指数(SRI)识别效果更好,可以更好地反映变化环境下的水文干旱演变趋势。

关键词：标准化径流指数自然-社会系统 GAMLSS模型非平稳四元驱动

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基于EnKF方法和SWAT模型的土壤湿度数据同化试验

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武汉大学学报（工学版） 2024年第1期57卷 17-27页

作者：刘永伟王文刘元波崔巍中国科学院南京地理与湖泊研究所流域地理学重点实验室江苏南京210008 河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 南京水利科学研究院江苏南京210017

基于集合卡尔曼滤波(ensemble Kalman filter,EnKF)方法和分布式水文模型SWAT(soil and water assessment tool),构建了一个土壤水分状态与参数同时更新的土壤湿度数据同化方案,通过遥感观测土壤湿度数据同化的仿真试验,研究土壤湿度数... 详细信息

基于集合卡尔曼滤波(ensemble Kalman filter,EnKF)方法和分布式水文模型SWAT(soil and water assessment tool),构建了一个土壤水分状态与参数同时更新的土壤湿度数据同化方案,通过遥感观测土壤湿度数据同化的仿真试验,研究土壤湿度数据同化在优化土壤水分参数、改进模型产汇流过程模拟方面的效果及潜力。结果表明:通过表层(0~5 cm)土壤湿度数据同化可实现土壤持水能力参数的准确估计;当给定的参数更新平滑因子在合理范围时,基于EnKF方法的参数优化效果具有较好的稳定性;表层土壤湿度数据同化对SWAT模型产汇流过程模拟有一定改进,但受降雨误差的影响,其对流域出口径流过程改进效果有限,表明基于遥感土壤湿度数据同化改进流域水文过程模拟还有赖于降雨输入精度及可靠性的提高。

关键词： EnKF SWAT 土壤湿度数据同化参数优化

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Responses of photosynthetic characteristics and enzyme activity of nitrogen metabolism to low nitrogen in maize with different nitrogen tolerance

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International Journal of Agricultural and Biological Engineering 2020年第6期13卷 133-143页

作者： Pengtao Ji yongwei cui Xiangling Li Kai Xiao Peijun Tao Yuechen Zhang College of Agronomy Hebei Agricultural University/State Key Laboratory of North China Crop Improvement and RegulationBaoding 071001HebeiChina Academy of Agricultural Planning and Engineering Ministry of Agriculture and Rural AffairsBeijing 100125China College of Agronomy and Biotechnology Hebei Normal University of Science&TechnologyQinhuangdao 066004HebeiChina

Understanding the physiological processes associated with leaf photosynthetic characteristics and nitrogen(N)assimilation during grain-filling stage are helpful for enhancing nitrogen utilization efficiency(NUtE)of maize.In this study,the leaf photosynthetic and N assimilation parameters in maize,including Zhengdan 958(ZD958),a low-N tolerance cultivar and Huanong 138(HN138),a low-N sensitive cultivar under different N rates were examined.Results showed that ZD958 displayed significant increases on grain yield and NUtE than that in HN138.Analyses on the leaf photosynthetic and N assimilation-associated processes indicated that ZD958 had higher leaf N remobilization(Rem N),net photosynthetic rate(Pn)and photosynthetic N use efficiency(PNUE)with respect to those of HN138 during grain-filling stage.In addition,ZD958 was also shown to be higher activities of leaf nitrate reductase(NR),glutamine synthetase(GS),nitrate reductase(GDH)and glutamine synthetase(GAGOT)than those of HN138.The leaf PNUE was significantly positively correlated with NR,GS,GDH,GOGAT suggesting that leaf PNUE and NR,GS,GDH,GOGAT jointly determined the N remobilization efficiency and the leaf N remobilization during post-silking.These results suggested that ZD958 possessed improved PNUE,NR and GS activities in leaves during grain-filling stage that contributes improve grain weights and yield formation capacities upon under low-N conditions.

关键词： low-N photosynthesis nitrogen assimilation nitrogen utilization efficiency maize

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混合特征及多头注意力的中文短文本分类

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计算机工程与应用 2024年第9期60卷 237-243页

作者：江结林朱永伟许小龙崔燕赵英男南京信息工程大学软件学院南京210044 南京信息工程大学江苏省大气环境与装备技术协同创新中心南京210044 南京特殊教育师范学院数学与信息科学学院南京210038 南京信息工程大学计算机学院、网络空间安全学院南京210044

传统的短文本分类研究方法存在两方面不足,一是不能全面地表示文本的语义信息,二是无法充分地提取和融合文本全局和局部信息。基于此,提出一种混合特征及多头注意力(HF-MHA)的中文短文本分类方法。该方法利用预训练模型计算中文短文本... 详细信息

传统的短文本分类研究方法存在两方面不足,一是不能全面地表示文本的语义信息,二是无法充分地提取和融合文本全局和局部信息。基于此,提出一种混合特征及多头注意力(HF-MHA)的中文短文本分类方法。该方法利用预训练模型计算中文短文本的字符级向量和词级向量表示,以得到更全面的文本特征向量表示;采用多头注意力机制捕捉文本序列中的依赖关系,以提高文本的语义理解;通过卷积神经网络分别提取两种向量表示的特征,并将其融合为一个特征向量,以整合文本的全局和局部信息;通过输出层得到分类结果。在三个公开数据集上的实验表明,HF-MHA能够有效地提升中文短文本分类的性能。

关键词：中文短文本分类注意力机制词级向量字符级向量

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Functions of Supply and Marketing Cooperatives in Improving Rural Modern Circulation System

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Asian Agricultural Research 2016年第2期8卷 15-18,27页

作者： Conghui DU yongwei cui Canvard Institute Beijing Technology and Business University Chinese Academy of Agricultural Engineering Ministry of Agriculture

This paper firstly described current development situation of China's rural circulation system. In the process of accelerating modernization,the supply and marketing cooperative is always an essential force,but the gap between urban and rural circulation system is still expanding. On the basis of current development situation,it analyzed functions of supply and marketing cooperatives in rural logistics system. Finally,it came up with recommendations for improving China's rural circulation system. In the new period,it is recommended to bring into play advantages of supply and marketing cooperatives,expand the coverage,gradually promote industry upgrade of renewable resource recycling,and constantly strengthen functions of supply and marketing cooperatives in building the rural modern circulation system,to build supply and marketing cooperatives into new forces and comprehensive platform for farmers' production and living services.

关键词： Supply and marketing cooperatives Rural modern circulation system Policy recommendations

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Brostrom-Gould修复术联合Internal Brace加强治疗慢性踝关节外侧不稳定的临床疗效

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中华骨与关节外科杂志 2024年第4期17卷 321-325页

作者：张琳袁吴佳俊崔崟付备刚蔡攀贾永伟沈超上海健康医学院附属周浦医院骨科上海201318

目的:探讨Brostrom⁃Gould修复术联合Internal Brace加强治疗慢性踝关节外侧不稳定(CLAI)的临床疗效。方法:回顾性分析2018年3月至2022年12月行Brostrom⁃Gould修复术联合Internal Brace加强治疗的32例CLAI患者的临床资料。其中男19例,女1... 详细信息

目的:探讨Brostrom⁃Gould修复术联合Internal Brace加强治疗慢性踝关节外侧不稳定(CLAI)的临床疗效。方法:回顾性分析2018年3月至2022年12月行Brostrom⁃Gould修复术联合Internal Brace加强治疗的32例CLAI患者的临床资料。其中男19例,女13例,年龄36(29,41)岁(23~56岁);运动损伤13例,日常扭伤15例,交通事故等其他损伤4例。记录术前及末次随访时美国足踝外科协会(AOFAS)踝-后足评分及踝关节Kofoed评分以评估踝关节功能,并记录疼痛视觉模拟评分(VAS),同时观察并发症发生情况。结果:所有患者均顺利完成手术,切口均一期愈合,术后1例患者出现腓浅神经损伤。所有患者均获得随访,随访时间17(14,18)个月(12~38个月)。末次随访时患者AOFAS踝-后足评分由术前的(68.4±10.4)分增加至(92.2±11.2)分;踝关节Kofoed评分由术前的(64.6±14.1)分增加至(90.0±7.9)分,疼痛VAS评分由术前的3.2(2.5,3.6)分降低至0.8(0.5,1.0)分,且差异均有统计学意义(P均<0.05)。1例患者术后6个月出现踝关节外侧紧缚感,经功能锻炼后好转。结论:Brostrom⁃Gould修复术联合Internal Brace加强治疗CLAI,提供了可靠的即刻稳定性,并发症发生率低,有利于患者早期功能锻炼,尽快恢复负重行走及日常生活。

关键词：慢性踝关节外侧不稳定 Brostrom-Gould修复术 Internal Brace

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心电图平板运动试验与动态心电图在冠心病诊断中的效能对比分析

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世界复合医学 2024年第3期10卷 77-79,86页

作者：张永卫崔慧玲张晨瑜长治市人民医院心电诊断科山西长治046000

目的比较心电图平板运动试验与动态心电图在冠状动脉粥样硬化性心脏病(coronary atherosclerotic heart disease,CAD)诊断中的效能。方法选取2022年1月—2024年1月长治市人民医院心电诊断科收治的158例疑似CAD患者,均实施心电图平板运... 详细信息

目的比较心电图平板运动试验与动态心电图在冠状动脉粥样硬化性心脏病(coronary atherosclerotic heart disease,CAD)诊断中的效能。方法选取2022年1月—2024年1月长治市人民医院心电诊断科收治的158例疑似CAD患者,均实施心电图平板运动试验、动态心电图检查。以冠状动脉造影结果为金标准,分析二者对冠心病的检出结果、诊断效能及CAD病变检出情况。结果冠状动脉造影结果显示,158例疑似CAD患者中阳性102例、阴性56例,其中动态心电图检测处阳性90例、阴性44例,心电图平板运动试验组阳性98例,阴性50例。心电图平板运动试验的灵敏度、特异度、准确度分别为96.10%、89.30%、93.70%,均高于动态心电图诊断的88.20%、78.60%、84.80%,差异有统计学意义(χ^(2)=4.347、4.391、9.828,P均<0.05)。结论心电图平板运动试验诊断CAD的灵敏度、特异度、准确度高于动态心电图。

关键词：心电图平板运动试验动态心电图冠心病诊断效能

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