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基于高光谱特征参数的马铃薯块茎形成期叶片含水量定量监测模型

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光谱学与光谱分析 2025年第3期45卷 774-783页

作者：苏亚拉其其格张振鑫李卓凌樊明寿贾立国赵金花内蒙古农业大学草原与资源环境学院植物学系内蒙古呼和浩特010019 内蒙古农业大学农学院植物生理系内蒙古呼和浩特010019

合理水分供应是马铃薯获得高产及优质块茎的必要前提。为实现马铃薯需水关键期的快速水分诊断,采用高光谱遥感和机器学习研究实时监测马铃薯块茎形成期植株水分状况的方法,为干旱地区马铃薯水分高效管理奠定基础。为了构建监测精度高、... 详细信息

合理水分供应是马铃薯获得高产及优质块茎的必要前提。为实现马铃薯需水关键期的快速水分诊断,采用高光谱遥感和机器学习研究实时监测马铃薯块茎形成期植株水分状况的方法,为干旱地区马铃薯水分高效管理奠定基础。为了构建监测精度高、更具普适性的马铃薯块茎形成期叶片含水量定量估算模型,测定了马铃薯冠层高光谱反射率及叶片含水量数据,筛选响应马铃薯叶片含水量的特征光谱参数,建立预测叶片含水量的偏最小二乘回归、支持向量机和BP神经网络模型。结果表明:针对马铃薯叶片含水量监测,筛选725、856和1000 nm等13个敏感波段,521、555和570 nm等11个特征光谱一阶导数和MSI、NDII、PSRI等7个特征光谱指数。构建的三种模型均能精确定量马铃薯块茎形成期的叶片含水量,说明上述组合光谱特征参数具有较强的实用型。采用全生育期叶片含水量和高光谱数据选择的特征光谱参数对马铃薯关键生育期叶片含水量的定量监测普适性更高,其中BP神经网络模型预测精度最佳。研究结果可以实时、准确地监测马铃薯叶片含水量,对于马铃薯植株水分状态的评估具有重要价值,为马铃薯的快速水分诊断及节水灌溉推荐提供技术支撑。

关键词：高光谱特征参数马铃薯叶片含水量定量监测

Quasi-periodic outflows observed by the X-Ray Telescope onboard Hinode in the boundary of an active region

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Research in Astronomy and Astrophysics 2010年第12期10卷 1307-1314页

作者： li-jia guo Hui Tian jian-Sen He School of Earth and Space Sciences Peking University Beijing 100871 China guolijia32 @ 163. com Max-Planck-Institut fur Sonnensystemforschung 37191 Katlenburg-Lindau Germany

Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an analy- sis of an image sequence obtained by the X-Ray Telescope onboard the Hinode spacecraft, we found that quasi-periodic outflows are present in the boundary of an active region. The flows are observed to occur intermittently, often with a period of 5-10 min. The proj ected flow speed can reach more than 200 km s^-1, while its distribution peaks around 50 km s^-1. This sporadic high-speed outflow may play an important role in the mass loading process of the slow solar wind. Our results may imply that the outflow of the slow solar wind in the boundary of the active region is intermittent and quasiperiodic in nature.

关键词： solar wind -- Sun: UV radiation -- active region

Gradient age-precipitation behavior induced by gradient nano-grain in Mg-Gd-Ag-Zr alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 19-24页

作者： Bang-jun li jia-peng Sun Jing Han guo-song Wu College of Materials Science and Engineering Hohai UniversityNanjing 210024JiangsuChina School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116JiangsuChina

Gradient nano-grained structure is frequently engineered into metallic materials,including Mg alloys,to achieve superior combination of strength and ***,the influence of this microstructural feature on aging precipitation behavior remains inadequately *** this study,the age-precipitation behavior of a gradient nano-grained Mg-Gd-Ag-Zr alloy prepared via ultrasonic severe surface rolling was *** result indicates that the aging precipitation behavior exhibits a depth-dependent variation within this *** the nano-grained surface layer,hierarchicalβnano-precipitates are predominant,while at greater depths,the precipitates consist ofβnanoparticles located at grain boundaries,along with intragranularβ′andγ″*** formation ofβnano-precipitates deviates from the conventional precipitation behavior observed in Mg-Gd-Ag alloys,and is attributed to the high density of defects induced by the surface nano-grained *** finding advances our understanding of the precipitation behavior in the alloys with heterogeneous microstructure.

关键词： Mg alloy Gradient Precipitation Aging behavior Microstructure

Advantages of the Multimodel Ensemble Approach for Subseasonal Precipitation Prediction in China and the Driving Factor of the MJO

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ADVANCES IN ATMOSPHERIC SCIENCES 2025年第3期42卷 551-563页

作者： guo, li Wu, Jie li, Qingquan jia, Xiaolong China Meteorol Adm Natl Climate Ctr Key Lab Climate Predict Studies Beijing 100081 Peoples R China Nanjing Univ Informat Sci & Technol Collaborat Innovat Ctr Forecast & Evaluat Meteorol Nanjing 210066 Peoples R China

Based on the hindcasts from five subseasonal-to-seasonal (S2S) models participating in the S2S Prediction Project, this study evaluates the performance of the multimodel ensemble (MME) approach in predicting the subseasonal precipitation anomalies during summer in China and reveals the contributions of possible driving factors. The results suggest that while single-model ensembles (SMEs) exhibit constrained predictive skills within a limited forecast lead time of three pentads, the MME illustrates an enhanced predictive skill at a lead time of up to four pentads, and even six pentads, in southern China. Based on both deterministic and probabilistic verification metrics, the MME consistently outperforms SMEs, with a more evident advantage observed in probabilistic forecasting. The superior performance of the MME is primarily attributable to the increase in ensemble size, and the enhanced model diversity is also a contributing factor. The reliability of probabilistic skill is largely improved due to the increase in ensemble members, while the resolution term does not exhibit consistent improvement. Furthermore, the Madden-Julian Oscillation (MJO) is revealed as the primary driving factor for the successful prediction of summer precipitation in China using the MME. The improvement by the MME is not solely attributable to the enhancement in the inherent predictive capacity of the MJO itself, but derives from its capability in capturing the more realistic relationship between the MJO and subseasonal precipitation anomalies in China. This study establishes a scientific foundation for acknowledging the advantageous predictive capability of the MME approach in subseasonal predictions of summer precipitation in China, and sheds light on further improving S2S predictions. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(S2S)(sic)(sic)(sic)(sic)(sic)5(sic)S2S(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(

关键词： multimodel ensemble subseasonal predictions summer precipitation S2S model MJO (sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic) S2S(sic)(sic)

Potato yield gaps across the rainfed Yin-mountain Hilly Area of China

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Journal of Integrative Agriculture 2018年第11期17卷 2418-2425页

作者： jia li-guo CHEN Yang QIN Yong-lin liANG Rui-fang CUl Shi-xin MA Zhong FAN Ming-shou College of Agronomy Inner Mongolia Agricultural University Hohhot 010018 P.R.China College of Ecology & Environmental Science Inner Mongolia Agricultural University Hohhot 010019 P.R.China Department of Biology Truman State University Kirksville MO 63501 USA

Yin-mountain Hilly Area is one of the ideal regions for potato （Solanum tuberosum） production in China. However, potato yield is severely limited as a result of rain-fed crop mode due to water deficiency, as well as an inadequate farming practices. In this study, yield gaps were determined by using attainable yield （Ya） as a benchmark under optimized management practices, i.e., micro-ridge and side planting with plastic-mulching （MS）, and flat planting with plastic-mulching （PM）. The yields under MS and PM modes are defined as Yal and Ya2, respectively. Under the same field with MS and PM modes but different densities and fertilizer usages and so on, it was defined as simulated farmers＇ practices. The yield of simulated farmers＇ practices （Yfl） reached 57.3 and 69.6% of Yal and Ya2, respectively, while the average yield of 298 randomly surveyed farmers （Yf2） reached only 37.0 and 47.8% of Yal and Ya2 for rain-fed potato, respectively. The gaps of water use efficiency exhibited similar pattern. Further analysis shows that improper measures in rainwater conservation and accumulation, and other management practices contributed to 18.5, 18.2, and 42.6% of yield gap between Yal and Yf2. Improper nutrition management, including overuse of nitrogen and the deficiency of phosphorus andpotassium supplication, was one of the important reasons of yield gap. The results indicate the possibilities of increasing rain-fed potato yields by optimized water and fertilizermanagements in the Yin-mountain Hilly Area.

关键词： rain-fed potato yield gap water management Yin-mountain Hilly Area

Design,synthesis and antifungal activities in vitro of novel tetralin compounds

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Chinese Chemical Letters 2008年第3期19卷 264-268页

作者： Hui Tang You Jun Zhou Yao Wu li jia guo Lv Can Hui Zheng Jun Chen Ju Zhu Department of Medicinal Chemistry School of Pharmacy Second Military Medical University Shanghai 200433 China

Novel chiral tetralin compounds were designed and synthesized, and their antifungal activities in vitro were tested. The results showed that all of target compounds had potent antifungal activities, and were stronger than that of control compounds tetrahydroisoquinolines. The binding model of lead molecules in the active site of CYP51 of Candida albicans showed that lead compound specifically interacted with the amino acids residues in the active site, without binding with the heme of CYP51, which was different from azole antifungal drugs. The present study might afford a novel lead molecule to develop non-azole CYP51 inhihitars of fungi.

关键词： Antifungal Chiral tetralins Lanosterol 14α-demethylase Design Synthesis

Super absorbent polymer seed coatings promote seed germinationand seedling growth of Caragana korshinskii in drought

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第8期18卷 696-706页

作者： li-qiang SU jia-guo li Hua XUE Xiao-feng WANG National Engineering Laboratory for Tree Breeding College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 China

Coating seeds with water absorbent materials can improve their survival, especially for those planted in drought or barren areas. In this study, effects of five kinds of super absorbent polymers(SAPs) on seed germination and seedling growth of Caragana korshinskii under drought conditions were investigated. Our results showed that SAP coatings could significantly improve the percentage and energy of seed germination, as well as reduce the relative electrical conductivity(REC), proline, malondialdehyde(MDA), H_2O_2 content, and peroxidase(POD) activity during germination. These results implied that seeds could uptake moisture from SAP coatings to alleviate drought-induced oxidative stress and membrane damage, thus exhibiting a better vigor and germination performance. After coating C. korshinskii seeds with SAPs, more seedlings emerged and grew better. Under the combined influence of the water absorption capacity of SAP and other factors, the efficiencies of five SAP coatings are in the sequence D>E>B>A>C. The function of the SAP coating on promoting seedling survival was confirmed in Mu Us Sandy Land in Ordos, Inner Mongolia Autonomous Region, China. The average seedling number of SAP D-coated seeds increased twofold on that of naked seeds. Our results are expected to be helpful in understanding and utilizing SAP seed coatings in improving plant survival under drought conditions.

关键词： Super absorbent polymer Seed coating Caragana korshinskii Seed germination Seedling Drought

Phase Transfer Catalyzed Synthesis under Ultrasonic Irradiation and Bioactivity of N'-(4,6-Disubstituted-pyrimidin-2-yl)-N-(5-aryl-2-furoyl) Thiourea Derivatives

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有机化学 2004年第Z1期24卷 237-238页

作者： KE,Shao-Yong WEI,Tai-Bao XUE,Si-jia DUAN,li-Ping guo,Yan-ling Department of Chemistry Shanghai Normal University Shanghai 200234 Department of Chemistry Northwest Normal University Lanzhou 730070 Department of Chemistry Shanghai Normal University Shanghai 200234 Department of Chemistry Shanghai Normal University Shanghai 200234 Department of Chemistry Shanghai Normal University Shanghai 200234

　　Acylthiourea derivatives are useful as pesticides, herbicides, fungicides and regulator for plant growth, and also as important intermediates in the organic synthesis. In recent years, phase transfer catalysis reaction technique has been widely recognized as an efficient synthetic tool and attracted much attention. In view of these observations, a series of 5-aryl-2-furoyl thioureas containing substituted pyrimidine ring were synthesized using PEG-400 as solid-liquid phase transfer catalyst under ultrasonic irradiation. All of the new compounds have been exactly determined by IR, 1H NMRand elemental analysis.……

关键词： phase transfer catalyst ultrasonic irradiation elemental analysis organic synthesis plant growth

Understanding amorphous PrO_(x)-based N-doped carbon catalyst as an efficient electrocatalyst for oxygen reduction reaction

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Journal of Rare Earths 2025年第1期43卷 73-80,I0003页

作者： Xiao Man Ying Chang Shaohong guo Meilin jia Jingchun jia Inner Mongolia Key Laboratory of Green Catalysis and Inner Mongolia Collaborative Innovation Center for Water Environment Safety College of Chemistry and Environmental ScienceInner Mongolia Normal UniversityHohhot010022China

The development of an e fficacious and easily prepared no nprecious metal electrocatalyst is crucial for the oxygen reduction reaction(ORR).This work used a dual template method to prepare the amorphous rare earth-based catalyst PrO_(x)-NC,and optimized the calcination temperature and *** PrO_(x)-NC-900 catalyst has high durability and activity and exhibits superior ORR performance in alkaline electrolytes with an onset potential(E_(0))of 0.96 V and a half-wave potential(E_(1/2))of 0.85 *** research results indicate that the ORR performance of rare earth oxide composite carbon catalysts can be improved by adjusting oxygen vacancies(Ov).In addition,high specific surface area,N rich defect *** oxygen vacancies,and the synergistic effect of oxygen vacancies and N-doped carbon interfacial layer play a significant part in the enhancement of *** performance of the zinc air battery assembled with PrO_(x)-NC-900 is significantly improved,and rare earth oxides and carbon frameworks originating from metal organic frameworks(MOFs)contribute to the oxygen electrocatalyst and electron transfer rate of the zinc air *** catalyst provides promising information for the development of rare earth metal oxide nanostructures as potential candidate materials for ORR in alkaline media.

关键词： Rare earths Metal-organic framework Oxygen reduction reaction Zn-air batteries