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Review of the detasseling techniques for maize (Zea mays L.) hybrid seed production

International Journal of Agricultural and Biological engineering 2024年第3期17卷 1-11页

作者： Zhang R. Yang J. Chen L. Ding C. Li L. Zhang L. national research center of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China national center of International research on Agricultural Aerial application Technology Beijing 100097 China research center of Intelligent Equipment Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China

Maize (Zea mays L.) is a critical staple crop globally, integral to human consumption, food security, and agricultural product stability. The quality and purity of maize seeds, essential for hybrid seed production, are contingent upon effective detasseling. This study investigates the evolution of detasseling technologies and their application in Chinese maize hybrid seed production, with a comparative analysis against the United States. A comprehensive examination of the development and utilization of detasseling technology in Chinese maize hybrid seed production was undertaken, with a specific focus on key milestones. data from the United States were included for comparative purposes. The analysis encompassed various detasseling methods, including manual, semi-mechanized, and cytoplasmic male sterility, as well as more recent innovations such as detasseling machines, and the emerging field of intelligent detasseling driven by unmanned aerial vehicles (UAVs), computer vision, and mechanical arms. Mechanized detasseling methods were predominantly employed by America. Despite the challenges of inflexible and occasionally overlooked, applying detasseling machines is efficient and reliable. At present, China’ s detasseling operations in hybrid maize seed production are mainly carried out by manual work, which is labor-intensive and inefficient. In order to address this issue, China is dedicated to developing intelligent detasseling technology. This study emphasizes the critical role of detasseling in hybrid maize seed production. The United States has embraced mechanized detasseling. The application and development of manual and mechanized detasseling were applied later than those in the United States, but latest intelligent detasseling technologies first appeared in China. Intelligent detasseling is expected to be the future direction, ensuring the quality and efficiency of hybrid maize seed production, with implications for global food security. © 2024, Chinese Socie

关键词： detasseling machine detasseling technique intelligent agriculture maize hybrid seed production UAVs

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Composition characterization and transformation mechanism of dissolved organic phosphorus in wastewater treatment using 31P NMR spectroscopy

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Frontiers of Environmental Science & engineering 2024年第3期18卷 103-113页

作者： Yuting Zhang Wei Shang SoonThiam Khu Xingcan Zheng Yongli Sun Pengfeng Li Miao Gu Wen-an Zhang Huanmei Ma national engineering research center For Urban Water&Wastewater North China Municipal Engineering Design&Research Institute Co.Ltd.Tianjin 300381China School of Environment Science&engineering Tianjin UniversityTianjin 300350China

The migration and transformation of phosphorus components in wastewater treatment plants(WWTPs)play a crucial role in the convergence and circulation of ***,the composition and variation of dissolved organic phosphorus(DOP)in WWTPs were unclear because of its complex nature,hindering its efficient *** this study,the DOP species and their transformation during the treatment process in WWTP were comprehensively ***,two enrichment methods were assessed for their effectiveness at facilitating wastewater analysis:lyophilization and aluminum salt *** salt precipitation was found to be better because its application allowed 31P nuclear magnetic resonance(31P NMR)spectroscopy to identify more species in the secondary effluent:orthophosphate(Ortho-P)(81.1%–89.3%of the dissolved total phosphorus),pyrophosphates(Pyro-P)(0%–2.3%),orthophosphate monoesters(Mono-P)(7.0%–10.77%),orthophosphate diesters(Di-P)(1.0%–2.96%),and phosphonate(Phos-P)(1.7%–5.16%).Furthermore,the variation and transformation mechanism of phosphorus,particularly those of DOP,during the entire sewage-treatment process were *** the treatment steps,biological treatment combined tertiary treatment achieved better DOP removal ***,biological treatment mainly removed Mono-P and Di-P with removal efficiencies of 33.3%and 41.7%compared with the effluent of the grit ***-P has higher bioavailability and is more easily converted and utilized by microorganisms than ***,Phos-P,with low bioavailability,was hardly utilized by microorganisms,which showed only 18.4%removal efficiency in biological *** tertiary treatment,coagulation process exhibited higher removal ability of Ortho-P(69.1%)and partial removal efficiencies of DOP,resulting in an increase in the DOP proportion in *** addition,Phos-P could not be effectively removed through the biological treatment and was only partially reduced via the adsorption pro

关键词： Municipal wastewater Dissolved organic phosphorus Composition Transformation 31P nuclear magnetic resonance

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Detection and analysis of landslide geomorphology based on UAV vertical photogrammetry

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Journal of Mountain Science 2024年第4期21卷 1190-1214页

作者： BI Rui GAN Shu YUAN Xiping LI Kun LI Raobo LUO Weidong CHEN Cheng GAO Sha HU Lin ZHU Zhifu School of Land and Resources engineering Kunming University of Science and TechnologyKunming 650093China Plication engineering research center of Spatial Information Surveying and Mapping Technology in Plateau and Mountainous Areas Set by Universities in Yunnan Province Kunming 650093China West Yunnan University of Applied Sciences Key Laboratory of Mountain Real Scene Point Cloud Data Processing and Application for Universities in Yunnan ProvinceDali 671006China

High-resolution landslide images are required for detailed geomorphological analysis in complex topographic environment with steep and vertical landslide *** study proposed a vertical route planning method for unmanned aerial vehicles(UAVs),which could achieve rapid image collection based on strictly calculated route *** effectiveness of this method was verified using a DJI Mavic 2 Pro,obtaining high-resolution landslide images within the Dongchuan debris flow gully,in the Xiaojiang River Basin,Dongchuan District,Yunnan,China.A three-dimensional(3D)model was constructed by the structure-from-motion and multi-view stereo(SfM-MVS).Micro-geomorphic features were analyzed through visual interpretation,geographic information system(GIS),spatial analysis,and mathematical statistics *** results demonstrated that the proposed method could obtain comprehensive vertical information on landslides while improving measurement *** 3D model was constructed using the vertically oriented flight route to achieve centimeter-level accuracy(horizontal accuracy better than 6 cm,elevation accuracy better than 3 cm,and relative accuracy better than 3.5 cm).The UAV technology could further help understand the micro internal spatial and structural characteristics of landslides,facilitating intuitive acquisition of surface *** slope of landslide clusters ranged from 36°to 72°,with the majority of the slope facing east and *** elevation levels were relatively consistent while middle to lower elevation levels gradually decreased from left to right with significant variations in lower elevation *** the rainy season,surface runoff was abundant,and steep topography exacerbated changes in surface *** route method is suitable for unmanned aerial vehicle(UAV)landslide surveys in complex mountainous *** geomorphological analysis methods used will provide references for identifying and describing topographic

关键词： UAV Landslide Vertical route SfM-MVS Topographic features

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Variable projection algorithms with sparse constraint for separable nonlinear models

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Control Theory and Technology 2024年第1期22卷 135-146页

作者： Hui-Lang Xu Guang-Yong Chen Si-Qing Cheng Min Gan Jing Chen College of Computer and data Science Fuzhou UniversityFuzhou350116FujianChina Fujian Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Intelligent Metro of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina engineering research center of big data Intelligence Ministry of EducationFuzhou UniversityFuzhou350116FujianChina School of Science Jiangnan UniversityWuxi214122JiangsuChina

Separable nonlinear models are widely used in various fields such as time series analysis, system modeling, and machine learning, due to their flexible structures and ability to capture nonlinear behavior of data. However, identifying the parameters of these models is challenging, especially when sparse models with better interpretability are desired by practitioners. Previous theoretical and practical studies have shown that variable projection (VP) is an efficient method for identifying separable nonlinear models, but these are based on \(L_2\) penalty of model parameters, which cannot be directly extended to deal with sparse constraint. Based on the exploration of the structural characteristics of separable models, this paper proposes gradient-based and trust-region-based variable projection algorithms, which mainly solve two key problems: how to eliminate linear parameters under sparse constraint;and how to deal with the coupling relationship between linear and nonlinear parameters in the model. Finally, numerical experiments on synthetic data and real time series data are conducted to verify the effectiveness of the proposed algorithms.

关键词： Variable projection(VP) Non-smooth constraint Separable nonlinear models

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Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de/hydrogenation performance of magnesium hydride

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Rare Metals 2024年第7期43卷 3273-3285页

作者： Meng-Chen Song Fu-Ying Wu Yi-Qun Jiang Xiu-Zhen Wang Hu Zhao Li-Xin Chen Liu-Ting Zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and Technology Max Planck Institute for Iron research School of Mechanical and Aerospace engineering Nanyang Technological University State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang University

The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride（MgH2） in sustainable energy ***,FeCoNiCrTi high-entropy alloy（HEA） nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH2to boost the hydrogen storage *** refined HEA exhibited superior catalytic activity on *** contrast to additive-free MgH2,the initial desorption temperature of the constructed MgH2-HEA composite was reduced from 330.0 to 198.5℃ and a remarkable 51% reduction in the dehydrogenation activation energy was ***,the MgH2-HEA composite only required one-twentieth time of that consumed by pure MgH2to absorb 5.0 wt% of H2at 225℃.The synergy between the "hydrogen pumping" effect of Mg2Ni/Mg2NiH4and Mg2Co/Mg2CoH5couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH2contributed to the enhanced de/hydrogenation performance of the MgH2-HEA *** study furnishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.

关键词： Hydrogen storage Magnesium hydride High-entropy alloys Catalysis

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Summer Atmospheric Water Cycle under the Transition Influence of the Westerly and Summer Monsoon over the Yarlung Zangbo River Basin in the Southern Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第5期41卷 830-846页

作者： Qianhui MA Chunyan ZHANG Donghai WANG Zihao PANG School of Atmospheric Sciences Sun Yat-sen UniversityGuangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesKey Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationZhuhai 519082China Southern Marine Science and engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Guangdong Meteorological data center Guangdong Meteorological ServiceGuangzhou 510080China national Observation and research Station of Coastal ecological Environments in Macao Macao Environmental Research InstituteMacao University of Science and TechnologyMacao SAR 999078China national Meteorological Information center China Meteorological AdministrationBeijing 100081China

This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan *** evolutions of moisture properties under the influence of the westerly and summer southerly monsoon are examined using 5-yr multi-source measurements and ERA5 reanalysis *** that moisture consumption in this study is associated with clouds,precipitation,and diabatic *** to the midstream and downstream regions,the upstream region has less moisture,clouds,and precipitation,where the moisture is brought by the *** early August,the vertical wet advection over this region becomes enhanced and generates more high clouds and *** midstream region has moisture carried by the westerly in June and by the southerly monsoon from July to *** higher vertical wet advection maximum here forms more high clouds,with a precipitation peak in early *** downstream region is mainly affected by the southerly-driven wet *** rich moisture and strong vertical wet advection here produce the most clouds and precipitation among the three regions,with a precipitation peak in late *** height of the maximum moisture condensation is different between the midstream region(325 hPa)and the other two regions(375 hPa),due to the higher upward motion maximum in the midstream *** diabatic heating structures show that stratiform clouds dominate the upstream region,stratiform clouds and deep convection co-exist in the midstream region,and deep convection systems characterize the downstream region.

关键词： Yarlung Zangbo River Basin atmospheric water cycle constrained variational analysis moisture source and consumption

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Constructing the Impossible Differential of Type-II GFN with Boolean Function and Its application to WARP

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Chinese Journal of Electronics 2024年第1期33卷 80-89页

作者： Jiali SHI Guoqiang LIU Chao LI College of Liberal Arts and Sciences National University of Defense Technology Hunan engineering research center of Commercial Cryptography Theory and Technology Innovation State Key Laboratory of Information Security Institute of Information Engineering

Type-Ⅱ generalized Feist el network(GFN) has attracted a lot of attention for its simplicity and high *** differential attack is one of the powerful cryptanalytic approaches for word-oriented block ciphers such as Feistel-like *** deduce the impossible differential of Type-Ⅱ GFN by analyzing the Boolean function in the middle *** main idea is to investigate the expression with the variable representing the plaintext(ciphertext) difference words for the internal state *** adopting the miss-in-the-middle approach,we can construct the impossible differential of Type-Ⅱ *** an illustration,we apply this approach to WARP,a lightweight 128-bit block cipher with a 128-bit key which was presented by Banik et *** SAC *** structure of WARP is a 32-branch Type-Ⅱ ***,we find two 21-round truncated impossible differentials and implement a 32-round key recovery attack on *** the 32-round key recovery attack on WARP,some observations are used to mount an effective *** the advantage of the early abort technique,the data,time,and memory complexities are 2125.69chosen plaintexts,2126.6832-round encryptions,and 2100-bit,*** the best of our knowledge,this is the best attack on WARP in the single-key scenario.

关键词： Ciphers Boolean functions Parallel processing Complexity theory

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analysis of the effect of the 2021 Semeru eruption on water vapor content and atmospheric particles using GNSS and remote sensing

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Geodesy and Geodynamics 2024年第1期15卷 33-41页

作者： Mokhamad Nur Cahyadi Arizal Bawasir Syachrul Arief Amien Widodo Meifal Rusli Deni Kusumawardani Yessi Rahmawati Ana Martina Putra Maulida Hilda Lestiana Department of Geomatics engineering Institut Teknologi Sepuluh NopemberSurabaya 60111Indonesia research center of Marine and Earth Science-Technology Directorate of Research and Community ServiceInstitut Teknologi Sepuluh NopemberSurabaya 60111Indonesia Geospatial Education and Training Division Geospatial Information Agency(BIG)Cibinong 16911Indonesia Department of Geophysics engineering Institut Teknologi Sepuluh NopemberSurabaya 60111Indonesia Department of Mechanical engineering Andalas UniversityPadang City 25175Indonesia Department of Economics Airlangga UniversitySurabaya 60286Indonesia research center for Geological Resources National Research and Innovation AgencyJakarta 10340Indonesia

Mount Semeru,an active volcano in East Java,Indonesia,erupted on December 4,2021,following extreme rainfall that caused an avalanche of hot pyroclastic flows and *** tropospheric conditions and dominant particle components in the atmosphere can be monitored using Global Navigation Satellite System(GNSS)technology and remote sensing *** signal propagation delay in Precise Point Positioning(PPP)processing can be used to determine Zenith Tropospheric Delay(ZTD)and Precipitable Water Vapor(PWV)variables so that atmospheric conditions can be *** addition,by using remote sensing satellite data,it is possible to obtain rainfall data with high temporal resolution as well as the dominant particle and gas content values during *** the eruption period,the high value of PWV was dominated by the high intensity of precipitation during the rainy *** rainfall before the eruption caused activity inside the mountain to increase,which occurred in avalanche type *** from that,the atmosphere around Semeru was also dominated by SO_(2)content,which spreaded for tens of ***_(2)content began to be detected significantly by remote sensing sensors on December 7,*** this study,deformation and atmospheric monitoring were also carried out using low-cost GNSS at the Semeru Monitoring Station on September 9-15,*** results of the ZTD and ZWD values show the dominance of the wet component,which is directly proportional to rainfall activity in this period.

关键词： Semeru GNSS Water vapor Rainfall SO_(2)

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High adsorption selectivity of activated carbon and carbon molecular sieve boosting CO_(2)/N_(2) and CH_(4)/N_(2) separation

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Chinese Journal of Chemical engineering 2024年第3期67卷 282-297页

作者： Siang Chen Wenling Wu Zhaoyang Niu Deqi Kong Wenbin Li Zhongli Tang Donghui Zhang The research center of Chemical engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Flue gas and coal bed methane are two important sources of greenhouse *** swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is *** this regard,in order to assess the better adsorbent for separating CO_(2) from flue gas and CH_(4) from coal bed methane,adsorption isotherms of CO_(2),CH_(4) and N_(2) on activated carbon and carbon molecular sieve are measured at 303.15,318.15 and 333.15 K,and up to 250 *** experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir-Freundlich models,and Clausius-Clapeyron equation was used to calculate the isosteric *** the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO_(2)>CH_(4)>N_(2).The adsorption kinetics are calculated by the pseudo-first kinetic model,and the order of adsorption rates on activated carbon is N_(2)-CH_(4)>CO_(2),while on carbon molecular sieve,it is CO_(2)-N_(2)>CH_(4).It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon,while kinetic diameter is the main resistance factor for carbon molecular ***,the adsorption selectivity of CH_(4)/N_(2) and CO_(2)/N_(2) were estimated with the ideal adsorption solution theory,and carbon molecular sieve performed best at 318.15 K for both CO_(2) and CH_(4) *** study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane.

关键词： Activated carbon Carbon molecular sieve Adsorbent evaluation Adsorption equilibrium and kinetics Heat of adsorption Selectivity

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Fabrication of corrosion inhibiting microcapsules functional coating and their high-efficiency corrosion resistance

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Rare Metals 2024年第2期43卷 842-848页

作者： Hao-Ran Yun Lu Lu Xue-Long Hao Xing-Xiang Zhang School of Material Science and engineering Tiangong UniversityTianjin300387China national center of analysis and Testing for Nonferrous Metals and Electronic Materials General Research Institute for Nonferrous MetalsBeijing100088China Guobiao(Beijing)Testing&Certification Co. Ltd.Beijing101407China

Benzotriazole(BTA)was loaded into calcium carbonate microsphere shell by self-assembly method and a new type of high-efficiency corrosion inhibiting microcapsules(CIMs)were fabricated,which were added and dispersed into epoxy resin coating to obtain a new corrosion resistance functional *** corrosion inhibition effect of benzotriazole on aluminum alloy matrix was verified by polarization curve *** effectiveness of the CIMs and their loading capacity on inhibitor were evaluated by scanning electron microscope,laser confocal Raman spectroscopy together with thermogravimetric analysis.

关键词： corrosion coating resistance

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