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Organic Chemistry Frontiers 2022年第5期9卷 1403-1409页

作者： Yong-Ji Hu Yu Zhou Jing-Jing Gao Han Zhang kai-rui yang Jia-Jun Li Xiao-Xin Yan Yuan-Lin Li Yan-Ping Zhu School of Pharmacy Key Laboratory of Molecular Pharmacology and Drug EvaluationMinistry of EducationCollaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of ShandongYantai UniversityShandongYantai264005P.R.China

An I_(2)-mediated[3+2]annulation of methyl-azaarenes with alkyl_(2)-isocyanoacetates or amino acid ester hydrochlorides has been *** strategy involves CuN bond cleavage of isocyanides and can selectively synthesize iodine-functionalized and non-iodine-functionalized fused ***-up experiments and arylation,alkynylation,alkenylation and selenization of iodine-functionalized products demonstrated the potential applications of this reaction.

关键词： reaction iodine fused

Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng TAO Shujun HAN Huici WU kai yang Zhu HAN National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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Industrial solid wastes to environmental protection materials for removal of gaseous pollutants:A review

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Green Energy & Environment 2025年第1期10卷 34-83页

作者： Jiacheng Bao Xin Sun Ping Ning kai Li Jie yang Fei Wang Lei Shi Maohong Fan Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming650500China College of Engineering and Physical Sciences and School of Energy ResourcesUniversity of WyomingLaramieWY82071USA College of Engineering Georgia Institute of TechnologyAtlantaGA30332USA

The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective *** this review,we investigate the development of industrialwaste-based functional materials for various gas pollutant removal and consider the relevant reaction mechanism according to different types of industrial solid *** see a recent effort towards achieving high-performance environmental functional materials via chemical or physical modification,in which the active components,pore size,and phase structure can be *** review will discuss the potential of using industrial solid wastes,these modified materials,or synthesized materials from raw waste precursors for the removal of air pollutants,including SO_(2),NO_(x),Hg^(0),H_(2)S,VOCs,and CO_(2).The challenges still need to be addressed to realize this potential and the prospects for future research *** suggestions for future directions include determining the optimal composition of these materials,calculating the real reaction rate and turnover frequency,developing effective treatment methods,and establishing chemical component databases of raw industrial solid waste for catalysts/adsorbent preparation.

关键词： Industrial solid waste Reaction mechanism Modification method Air pollutants

Phase saddle point transformation-enabled mode-adaptive detection of acoustic orbital angular momentum with high efficiency and low crosstalk

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： kai Wu yang Tan Jingjing Liu Bin Liang Jianchun Cheng Collaborative Innovation Center of Advanced Microstructures and Key Laboratory of Modern Acoustics MOE Institute of AcousticsDepartment of Physics Nanjing University

Acoustic orbital angular momentum (OAM) provides an infinite set of orthogonal bases in Hilbert space and significantly boosts the link capacity and data transmission rate. High-capacity and low-crosstalk OAM detection within compact physical space is highly desired to effectively harness this spatial dimension of sound wave, but the existing mechanisms generally either operate only for finite OAMs with predetermined mode orders or rely on complicated active devices. Here, we propose a phase saddle point (PSP) transformation mechanism for distinguishing and demultiplexing acoustic OAM modes in a passive, mode-adaptive,high-efficiency, and high-accuracy paradigm. The phase mask characterized by a PSP in the specific area is created through the single-pass log-polar transformation without prior information of incident modes, whose interaction with incident vortex beams of different OAM modes will yield the translation of the stationary phase point and thereby generate the corresponding focused line spots at distinct lateral positions. We theoretically elucidate the mode-adaptive response of PSP transformation by deriving the quantitative relationship between the OAM order and line spot offset. This mode adaptability enables our mechanism to detect OAM of arbitrary mode orders and mode numbers with the inter-mode crosstalk being effectively suppressed, beyond attainable with the existing methods. The effectiveness of our proposed mechanism is validated by demonstrating several distinct examples of single-mode OAM sorting and multi-mode synthesized vortex beam demultiplexing. We anticipate this modeadaptive methodology, designed for compact dimensions and featuring with low crosstalk and uniform efficiency, will find important applications in OAM information processing.

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Repetitive transcranial magnetic stimulation in Alzheimer’s disease:effects on neural and synaptic rehabilitation

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Neural Regeneration Research 2025年第2期20卷 326-342页

作者： Yi Ji Chaoyi yang Xuerui Pang Yibing Yan Yue Wu Zhi Geng Wenjie Hu Panpan Hu Xingqi Wu kai Wang Department of Neurology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders HefeiAnhui ProvinceChina Collaborative Innovation Center of Neuropsychiatric Disorders and Mental Health HefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina Department of Psychology and Sleep Medicine The Second Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina

Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and *** Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life,leaving patients *** transcranial magnetic stimulation is a cost-effective,neuro-modulatory technique used for multiple neurological *** the past two decades,it has been widely used to predict cognitive decline;identify pathophysiological markers;promote neuroplasticity;and assess brain excitability,plasticity,and *** has also been applied to patients with dementia,because it can yield facilitatory effects on cognition and promote brain recovery after a neurological ***,its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of *** study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment,evaluate its effects on synaptic plasticity,and identify the associated *** review essentially focuses on changes in the pathology,amyloidogenesis,and clearance pathways,given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer’s *** mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription,which are closely related to the neural regeneration process,are also ***,we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation,with the aim to highlight future directions for better clinical translations.

关键词： Alzheimer’s disease amyloid deposition apoptotic mechanisms biomarker neural regeneration neurodegeneration repetitive transcranial magnetic stimulation synaptic plasticity

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Microstructure and Wear/corrosion Resistance of Stainless Steel Laser-alloyed with Mn+W_(2)C, Mn+NiWC and Mn+SiC

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 283-294页

作者： ZHOU rui DIAO Xiaogang SUN Yixin School of Metallurgical Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China CITIC Heavy Cast Iron Industry Co. Ltd.Luoyang 417039China

In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed *** evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were *** indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LSA with Mn+W_(2)C and Mn+NiWC while SiC totally dissolved into the high Mn matrix when adding Mn+*** as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C *** improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.

关键词： laser surface alloying stainless steel carbide type microstructure wear and corrosion resistance

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Reversing anther thermotolerance by manipulating the cis-elements in the promoter of a high-temperature upregulated gene Casein Kinase I in upland cotton

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Science China Life Sciences 2025年

作者： Yanlong Li Yinuo Fu Yaoyao Li rui Zhang Jing yang Huanhuan Ma Ling Min Xianlong Zhang National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University

High temperature (HT) stress causes male sterility,leading to reduced upland cotton ***,we identified a key gene,Casein Kinase I (GhCKI),that negatively regulates male fertility in upland cotton under ***,conventional genetic manipulations of GhCKI would result in male sterility,hindering its utilization in breeding ***,we engineered quantitative variation for anther thermotolerance-related traits in upland cotton by creating weak promoter alleles of GhCKI genes,using CRISPR/Cas9 and CRISPR/Cpf1genome ***,we screened and identified two new upland cotton plant lines exhibiting a HT-tolerant phenotype with edited GhCKI promoters,and characterized their corresponding heat-tolerant allelic *** research revealed that the primary reason for the HT tolerance of the GhCKI promoter editing mutants is that the trans-acting factors GhMYB73 and GhMYB4,which positively regulate GhCKI expression under HT,failed to bind and activate the expression of ***,our study not only provides a rapid strategy to generate new beneficial alleles but also offers novel germplasm resources and molecular insights for crop HT tolerance breeding.

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Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying Ding Ying-Chao Li Yuan-Feng Wu Yuan-yang Xu rui Chen Xiao-Lei Zhao Hai-Yong Wang Da-Lei Zhang Yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

Construction of Power Trading Supply Guarantee System of High Proportion of Hydropower in the Southwest Power Grid Under Extreme Climate Scenarios

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Dianwang Jishu/Power System Technology 2025年第1期49卷 113-123页

作者： Wen, Xu Zhou, Quan Sun, Tian yang, yang Mao, rui Wen, Siao Southwest Branch of State Grid Corporation of China Sichuan Province Chengdu 610041 China Beijing Power Trading Center Co. Ltd. Xicheng District Beijing 100031 China

Currently, the Southwest Power Grid is promoting the construction of a new power system. The southwest power grid has a large-scale integration of clean energy, mainly hydropower, which depends on the weather. The system operation is facing serious challenges due to the lack of reliable power supply and the frequent occurrence of extreme climate. Firstly, this paper introduces China's Southwest Power Grid and market operation pattern. Secondly, learning from the power supply issues in the Sichuan-Chongqing region of the Southwest Power Grid under the extreme drought, and high-temperature climate scenarios in the summer of 2022, and based on the perspectives of the regional power grid and the marketization, the paper summarizes the four shortcomings of current power supply scheme of Southwest Power Grid, namely limited warning levels, short supply cycle, limited supply space, and a single supply resource. Therefore, research methods and framework for the power supply of Southwest Power Grid are proposed based on the concept of "double-level, full-lifecycle, full-space, and full-resources" ("one-double three-full"). Thirdly, the power trading system for supply sufficiency in Southwest Power Grid under extreme climate scenarios is constructed: 1) proposing the concept and level determination method of power supply warning and response for regional power grids, and constructing a double-level power trading supply warning and response mechanism for "provincial power grid + regional power grid";2) proposing medium and long term interruptible power supply varieties and constructing a "medium and long term + spot + emergency" full-lifecycle power trading supply guarantee system;3) proposing the concept of inter-regional and intra-provincial market power supply, designing spatiotemporal exchange transactions of large-scale hydropower and constructing a "inter-regional + inter-provincial + intra-provincial" full-space power trading system for supply sufficiency;4) proposing p

关键词： Commerce

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan yang Han Jia Tuo Liu Yuzhen yang Jun yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter