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Rice science 2013年第3期20卷 220-228页

作者： LONG Ji-rui MA Guo-hui wan yi-zheng SONG Chun-fang SUN Jian QIN Rui-jun State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Center Liuyang Yongan Agricultural Technology Popularity Center University of California

To compare the effects of slow-release nitrogen fertilizer at six different levels on the flag leaf chlorophyll fluorescence characteristics of super hybrid rice, a field fertilization experiment was conducted with super hybrid rice Y Liangyou 1 as a test material. The photosynthetic electron transport rate （ETR）, effective quantum yield （EQY）, photochemical quenching coefficient （qp）, and non-photochemical quenching coefficient （NPQ） of flag leaves were measured at the initial heading, full heading, 10 d after full heading and 20 d after full heading stages. Results showed that the values of ETR, EQY and qp increased with rice development from initial heading to 20 d after full heading, whereas the NPQ decreased. During the measured stages, ETR, EQY and qp increased initially and then decreased as nitrogen application amount increased, but they peaked at different nitrogen fertilizer levels. The maximum ETR and EQY values appeared at the treatment of 135 kg/hm2 N. In conclusion, the optimum nitrogen amount for chlorophyll fluorescence characteristics of super hybrid rice was 135-180 kg/hm2.

关键词： super hybrid rice slow-release nitrogen fertilizer chlorophyll fluorescence nitrogen-saving cultivation

The Logarithmic Sobolev Inequality for a Submanifold in Manifolds with Nonnegative Sectional Curvature

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 487-496页

作者： Chengyang yi Yu zheng School of Mathematical Sciences East China Normal UniversityShanghai 200241China

The authors prove a sharp logarithmic Sobolev inequality which holds for compact submanifolds without boundary in Riemannian manifolds with nonnegative sectional curvature of arbitrary dimension and *** the Michael-Simon Sobolev inequality,this inequality includes a term involving the mean *** extends a recent result of Brendle with Euclidean setting.

关键词： Logarithmic Sobolev inequality Nonnegative sectional curvature Submanifold

The breaking of spin symmetry in the single-particle resonances in deformed nuclei

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Nuclear Science and Techniques 2024年第3期35卷 237-245页

作者： Zhen-Yu zheng Shou-wan Chen Quan Liu School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus *** this study,we solve the Dirac equation from the relativistic mean field (RMF) in complex momentum *** investigated SS and its breaking in single-particle resonant states within deformed nuclei,with a focus on the illustrative *** was the initial discovery of a resonant spin doublet in a deformed nucleus,with the expectation of the SS approaching the continuum *** increasing single-particle energy,the splitting of the resonant spin doublets widened *** escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy levels *** also analyzed the width of the resonant states,showing that lower orbital angular momentum resonances possess shorter decay times and that SS is preserved within broad resonant doublets,as opposed to narrow resonant *** the radial density of the upper components for the bound-state and resonant-state doublets,it becomes evident that while SS is well-preserved in the bound states,it deteriorates in the resonant *** impact of nuclear deformation (β_(2)) on SS was examined,demonstrating that an increase in β_(2) resulted in higher energy and width splitting in the resonant spin doublets,which is attributed to increased component ***,the sensitivity of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in *** study provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay with the nuclear structure,thereby advancing our understanding of SS in the resonance state.

关键词： Spin symmetry Resonant states Deformed nuclei Complex-momentum representation

Low-dimensional van der Waals materials for linear-polarization-sensitive photodetection: materials, polarizing strategies and applications

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Materials Futures 2024年第1期3卷 95-127页

作者： Yuhang Ma Huaxin yi Huanrong Liang wan wang Zhaoqiang zheng Jiandong Yao Guowei Yang State Key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterSchool of Materials Science&EngineeringSun Yat-sen UniversityGuangzhou 510275GuangdongPeople’s Republic of China Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices Sun Yat-sen UniversityGuangzhou 510275GuangdongPeople’s Republic of China School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006GuangdongPeople’s Republic of China

Detecting light from a wealth of physical degrees of freedom(***,intensity,polarization state,phase,etc)enables the acquirement of more comprehensive *** the past two decades,low-dimensional van der Waals materials(vdWMs)have established themselves as transformative building blocks toward lensless polarization optoelectronics,which is highly beneficial for optoelectronic system *** review provides a comprehensive overview on the recent development of low-dimensional vdWM polarized *** begin with,the exploitation of pristine 1D/2D vdWMs with immanent in-plane anisotropy and related heterostructures for filterless polarization-sensitive photodetectors is ***,we have systematically epitomized the various strategies to induce polarization photosensitivity and enhance the degree of anisotropy for low-dimensional vdWM photodetectors,including quantum tailoring,construction of core–shell structures,rolling engineering,ferroelectric regulation,strain engineering,etc,with emphasis on the fundamental physical *** that,the ingenious optoelectronic applications based on the low-dimensional vdWM polarized photodetectors,including multiplexing optical communications and enhanced-contrast imaging,have been *** the end,the current challenges along with the future prospects of this burgeoning research field have been *** the whole,the review depicts a fascinating landscape for the next-generation high-integration multifunctional optoelectronic systems.

关键词： polarization-discriminating photodetectors 1D van der Waals materials

Coarse-fine joint target parameter estimation method based on AN-RSC in OFDM passive radar

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Journal of Systems Engineering and Electronics 2024年第2期35卷 339-349页

作者： wanG Chujun wan Xianrong yi Jianxin CHENG Feng School of Electronic Information Wuhan UniversityWuhan 430072China

In this paper,we study the accuracy of delay-Doppler parameter estimation of targets in a passive radar using orthogonal frequency division multiplexing(OFDM)signal.A coarse-fine joint estimation method is proposed to achieve better estimation accuracy of target parameters without excessive computational ***,the modulation symbol domain(MSD)method is used to roughly estimate the delay and Doppler of ***,to obtain high-precision Doppler estimation,the atomic norm(AN)based on the multiple measurement vectors(MMV)model(MMV-AN)is used to manifest the signal sparsity in the continuous Doppler *** the same time,a reference signal compensation(RSC)method is presented to obtain highprecision delay *** results based on the OFDM signal show that the coarse-fine joint estimation method based on AN-RSC can obtain a more accurate estimation of target parameters compared with other *** addition,the proposed method also possesses computational advantages compared with the joint parameter estimation.

关键词： passive radar orthogonal frequency division multiplexing(OFDM)signal atomic norm(AN) parameter estimation

Enhancing comprehension of water vapor on adsorption performance of VOC on porous carbon materials and its application challenge

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 51-66页

作者： Xiaolong Yao Kuan wan Wenxin Yu zheng Liu School of Ecology and Environment Beijing Technology and Business UniversityBeijing 100048China State Environmental Protection Key Laboratory of Food Chain Pollution Control Beijing Technology and Business UniversityBeijing 100048China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China

Volatile organic compounds(VOC)have been proven to cause considerable harm to both the ecological environment and human *** VOC emissions are primarily generated by the industrial *** utilization of porous carbon as an adsorbent has emerged as an effective method for the efficient removal of VOC from industrial ***,during the actual production processes,VOC exhaust gases are often mixed with water vapor,which poses challenges for adsorption *** review provides a comprehensive overview of the remarkable advancements in various carbon materials in terms of their ability to adsorb both VOC and water ***,it systematically summarizes the influence of surface groups on adsorbents and the molecular properties of VOC on their adsorption by carbon ***,this review introduces the mechanism underlying adsorption-adsorbent interactions and discusses the construction of models for adsorbing water vapor and *** challenges associated with the application of carbon materials for VOC adsorption in humid environments are also *** review aims to offer theoretical and technical guidance for the effective purification of moist VOC waste gases emitted from industrial sources,thereby achieving precise control of VOC emissions.

关键词： Adsorption Water vapor Carbon-based adsorbents Surface functional groups VOC properties

Synthesis of Diverse Oxetane Amino Acids via Visible-Light-Induced Photocatalytic Decarboxylative Giese-Type Reaction

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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang Shi yi wan Yongqiang Zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions

Understanding the combustion behavior of electric bicycle batteries and unveiling its relationship with fire extinguishing

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Journal of Energy Chemistry 2024年第4期91卷 609-618页

作者： Zhanglong Yu Xueling Shen Ran Xu zheng wang Zengming wan Mingyang Chen yi Cui Yanyan Fang Xiaoli Ma China Automotive Battery Research Institute Co. Ltd.Beijing 101407China China Grinm Group Co. Ltd.Beijing 100088China Ministry of Industry and Information Technology Equipment Industry Development CenterBeijing 100846China Hefei Guoxuan High-tech Power energy Co. Ltd.Hefei 230000AnhuiChina

In this study,a detailed analysis of the combustion behaviors of the lithium iron phosphate(LFP)and lithium manganese oxide(LMO)batteries used in electric bicycles was *** research included quantitative measurements of the combustion duration,flame height,combustion temperature,heat release rate,and total heat *** results indicated that LMO batteries exhibited higher combustion temperatures of 600–700°C,flame heights of 70–75 cm,a significantly higher heat release rate of40.1 k W(12 Ah),and a total heat release of 1.04 MJ(12 Ah)compared to LFP batteries with the same *** on these experimental results,a normalized total heat release(NORTHR)parameter was proposed,demonstrating good universality for batteries with different *** this parameter,quantitative calculations and optimization of the extinguishing agent dosage were conducted for fires involving these two types of batteries,and the method was validated by extinguishing fires for these two types of battery packs with water-based extinguishing fluids.

关键词： Combustion behavior Electric bicycle Lithium-ion battery Fire extinguishing Normalized total heat release

Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： wanG yi-guang GUO zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

Immunobiology of COVID-19: Mechanistic and therapeutic insights from animal models

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Zoological Research 2024年第4期45卷 747-766页

作者： Hong-yi zheng Tian-Zhang Song Yong-Tang zheng State Key Laboratory of Genetic Evolution&Animal Models KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesCenter for Biosafety Mega-ScienceKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China National Resource Center for Non-Human Primates National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China

The distribution of the immune system throughout the body complicates in vitro assessments of coronavirus disease 2019(COVID-19)immunobiology,often resulting in a lack of reproducibility when extrapolated to the whole ***,developing animal models is imperative for a comprehensive understanding of the pathology and immunology of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** review summarizes current progress related to COVID-19 animal models,including non-human primates(NHPs),mice,and hamsters,with a focus on their roles in exploring the mechanisms of immunopathology,immune protection,and long-term effects of SARS-CoV-2 infection,as well as their application in immunoprevention and immunotherapy of SARS-CoV-2 *** among these animal models and their specific applications are also highlighted,as no single model can fully encapsulate all aspects of *** effectively address the challenges posed by COVID-19,it is essential to select appropriate animal models that can accurately replicate both fatal and non-fatal infections with varying courses and *** animal model libraries and associated research tools is key to resolving the global COVID-19 pandemic,serving as a robust resource for future emerging infectious diseases.

关键词： SARS-CoV-2 COVID-19 Animal models Infection immunology Immunotherapy