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Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel research center Research Institute of Highway Ministry of TransportBeijing 100088China Tunnel and Underground Engineering research center of Ministry of education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service *** aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single *** used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track ***,the numerical method was verified by comparing the results of numerical simulation and on-site ***,the characteristics of aerodynamic pressure were ***,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was *** results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel *** addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel *** pressure amplitude in the two-train case is higher than that for a single *** maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage *** P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage *** P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Feeding behavior and hormoligosis associated with imidacloprid resistance in Asian citrus psyllid,Diaphorina citri

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Insect Science 2024年第4期31卷 1211-1221页

作者： Xue Dong Chen Justin George Lauren M.Diepenbrock Hunter Gossett Guoping Liu Jawwad A.Qureshi Lukasz L.Stelinski Entomology and Nematology Department University of FloridaCitrus Research and Education CenterLake AlfredFloridaUSA Southern Insect Management research Unit USDA-ARSStonevilleMississippiUSA Entomology and Nematology Department University of FloridaSouthwest Florida Research and Education CenterImmokaleeFloridaUSA

Imidacloprid is a neonicotinoid insecticide used for managing the Asian citrus psyllid,Diaphorina citri Kuwayama,which serves as vector of phytopathogens causing citrus ***,development of resistance to neonicotinoids among populations of *** has coincided with occasional control failures in the *** objectives of this research were to(1)survey current levels of imidacloprid resistance in Florida citrus;(2)compare feeding behavior between imidacloprid-resistant and susceptible *** using electrical penetration graph recordings,and(3)investigate the possible amplification of insecticide hormoligosis associated with *** surveys confirmed that the susceptibility of *** populations to imidacloprid has decreased in commercial Florida citrus groves compared with a laboratory-susceptible *** 12 generations of selection,resistance to imidacloprid increased by 438 fold compared with the susceptible ***-susceptible *** feeding on citrus exhibited significantly more bouts associated with intercellular pathway(C),phloem penetration(D),phloem salivation(E1),and nonprobing(Np)activities than imidacloprid-resistant ***,there were no differences observed in the frequency or duration of phloem ingestion or xylem feeding between susceptible and resistant *** was no statistical difference in fecundity between resistant and susceptible ***,the fecundity of imidacloprid-susceptible female *** treated with a sublethal concentration of imidacloprid(LC_(25))increased significantly compared with controls,while such hormoligosis was less pronounced among imidacloprid-resistant *** results suggest that imidacloprid-resistant psyllids may cease feeding sooner than susceptible counterparts following sublethal exposure to this insecticide,indicative of a behavioral resistance mechanism.

关键词： artificial selection electrical penetration graph feeding behavior hormoligosis insecticide resistance sublethal exposure

SnIP-type atomic-scale inorganic double-helix semiconductors: Synthesis, properties, and applications

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Nano research 2024年第3期17卷 2111-2128页

作者： Mudussar Ali Bowen Zhang Muhammad Khurram Qingfeng Yan Engineering research center of Advanced Rare Earth Materials(Ministry of education) Department of ChemistryTsinghua UniversityBeijing 100084China

Flexible inorganic double helical semiconductors similar to DNA have fueled the demand for efficient materials with innovative structures and excellent *** recent discovery of tin phosphide iodide(SnIP),the first carbon-free double helical semiconductor at an atomic level,has opened new avenues of research for semiconducting devices such as thermoelectric and sensor devices,solar cells,and *** has drawn significant academic attention due to its high structural flexibility,band gap in the visible spectrum range,and non-toxic ***,the recent progress in developing SnIP,including its prestigious structure,versatile and intriguing properties,and synthesis,is *** analogues of SnIP and SnIP-based hybrid materials and their applications in photocatalysis are also ***,the review concludes with a critical summary and future aspects of this new inorganic semiconductor.

关键词： tin phosphide iodide(SnIP) inorganic semiconductor inorganic double helix SnIP-based hybrids photocatalysis flexible material

Physiology of medicinal and aromatic plants under drought stress

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The Crop Journal 2024年第2期12卷 330-339页

作者： Zohreh Emami Bistgani Allen V.Barker Masoud Hashemi Isfahan Agricultural and Natural Resources research and education center Agricultural Research Education and Extension Organization(AREEO)Isfahan 81748-35117Iran Stockbridge School of Agriculture University of MassachusettsAmherstMA 01002USA

Drought poses a significant challenge,restricting the productivity of medicinal and aromatic *** strain induced by drought can impede vital processes like respiration and photosynthesis,affecting various aspects of plants’growth and *** response to this adversity,medicinal plants employ mechanisms such as morphological and structural adjustments,modulation of drought-resistant genes,and augmented synthesis of secondary metabolites and osmotic regulatory substances to alleviate the *** water scarcity can lead to leaf wilting and may ultimately result in plant *** cultivation and management of medicinal plants under stress conditions often differ from those of other *** is because the main goal with medicinal plants is not only to increase the yield of the above-ground parts but also to enhance the production of active ingredients such as essential *** elucidate these mechanisms of drought resistance in medicinal and aromatic plants,the current review provides a summary of recent literature encompassing studies on the morphology,physiology,and biochemistry of medicinal and aromatic plants under drought conditions.

关键词： Drought stress Medicinal and aromatic plants Phytochemistry Physiology

Progress in processing of porous titanium:a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： Xiao-Li Yang Xian-Feng Du Zhi-Lin Xu Zhong-Shuai Liang Li-Long Xiong Engineering research center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi'an Jiaotong UniversityXi'an 710049China

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace,marine engineering and biomedical fields due to their high corrosion resistance,low density,good biocompatibility and excellent mechanical ***,in this paper,a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes)for fabricating porous titanium is firstly covered in terms of their working principles,capabilities,shortcomings and ***,the influencing factors of various methods on final pore structure of porous Ti are ***,a summary of the chemical methods(CM)to obtain the porous Ti is also provided,such as dealloying method and reduction ***,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Observation of an upward lightning flash with 21 upward positive leaders initiated from different wind turbines in wind farm

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High Voltage 2024年第1期9卷 163-171页

作者： Li Cai Yifeng Ke Wenchao Fan Ruisheng Yan Mi Zhou Jianguo Wang Yadong Fan Engineering research center of Ministry of education for Lightning Protection and Grounding Technology School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

As the wind turbine height increases,the probability of multiple upward leaders flashes within the wind farm *** this study,an upward lightning flash containing 21 upward positive leaders(UPLs)initiated from different wind turbines in Zhangbei Wind Farm was *** average speed of the UPLs was 1.2×10^(5) m/s,which mostly decreased to zero before reaching the cloud *** four UPLs developed to cloud height,with prolonged periods of bright light on three of them and with a minimum duration of 126 ms.A total of nine return strokes occurred on the other two dissipated leader channels,and the numbers of strokes on the two channels was six and three,*** average interstroke interval for the return strokes was 10.5 *** of these nine return strokes had peak currents smaller than 10 *** high-speed video frames confirmed that competition does exist between the UPLs,and the range of shielding effects increases as the height of the ULs *** effect of fan rotation on the initiation of upward leaders and the shielding effect between the wind turbines and upward leaders are discussed.

关键词： flash return initiated

Map-based cloning of q LP_(A01.1),a favorable allele from the Gossypium tomentosum chromosome segment line

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Journal of Integrative Agriculture 2024年第10期23卷 3283-3293页

作者： Wenwen Wang Lei Chen Yan Wu Xin Guo Jinming Yang Dexin Liu Xueying Liu Kai Guo Dajun Liu Zhonghua Teng Yuehua Xiao Zhengsheng Zhang Engineering research center of South Upland Agriculture Ministry of EducationSouthwest UniversityChongqing 400716China

Cotton is an important natural fiber crop worldwide which plays a vital role in our daily *** yield is a constant goal of cotton breeding,and lint percentage(LP)is one of the important components of cotton fiber yield.A stable QTL controlling LP,qLP_(A01.1),was identified on chromosome A01 from Gossypium hirsutum introgressed lines with *** chromosome segments in a previous *** fine-map qLP_(A01.1),an F2 population with 986individuals was established by crossing *** cultivar CCRI35 with the chromosome segment substitution line HT_390.A high-resolution genetic map including 47 loci and spanning 56.98 cM was constructed in the QTL region,and qLP_(A01.1)was ultimately mapped into an interval corresponding to an~80 kb genome region of chromosome A01in the reference genome,which contained six annotated *** data and sequence analysis revealed that S-acyltransferase protein 24(GoPAT24)might be the target gene of qLP_(A01.1).This result provides the basis for cotton fiber yield improvement via marker-assisted selection(MAS)and further studies on the mechanism of cotton fiber development.

关键词： cotton lint percentage fine-mapping qLPA01.1 GoPAT24

FSCIL-EACA: Few-Shot Class-Incremental Learning Network Based on Embedding Augmentation and Classifier Adaptation for Image Classification

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Chinese Journal of Electronics 2024年第1期33卷 139-152页

作者： Ruru ZHANG Haihong E Meina SONG School of Computer Science Beijing University of Posts and Telecommunications education Department Information Network Engineering research center Beijing University of Posts and Telecommunications

The ability to learn incrementally is critical to the long-term operation of AI systems. Benefiting from the power of few-shot class-incremental learning(FSCIL), deep learning models can continuously recognize new classes with only a few samples. The difficulty is that limited instances of new classes will lead to overfitting and exacerbate the catastrophic forgetting of the old classes. Most previous works alleviate the above problems by imposing strong constraints on the model structure or parameters, but ignoring embedding network transferability and classifier adaptation(CA), failing to guarantee the efficient utilization of visual features and establishing relationships between old and new classes. In this paper, we propose a simple and novel approach from two perspectives: embedding bias and classifier bias. The method learns an embedding augmented(EA) network with cross-class transfer and class-specific discriminative abilities based on self-supervised learning and modulated attention to alleviate embedding bias. Based on the adaptive incremental classifier learning scheme to realize incremental learning capability,guiding the adaptive update of prototypes and feature embeddings to alleviate classifier bias. We conduct extensive experiments on two popular natural image datasets and two medical datasets. The experiments show that our method is significantly better than the baseline and achieves state-of-the-art results.

关键词： Training Adaptation models Visualization Image recognition Prototypes Self-supervised learning Power capacitors

Nitrogen-doping boosts *CO utilization and H2O activation on copper for improving CO2 reduction to C2+ products

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Green Energy & Environment 2024年第9期9卷 1459-1465页

作者： Yisen Yang Zhonghao Tan Jianling Zhang Jie Yang Renjie Zhang Sha Wang Yi Song Zhuizhui Su Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Center for Carbon Neutral Chemistry Institute of Chemistry Chinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences Key Laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

To improve the electrocatalytic transformation of carbon dioxide （CO2） to multi-carbon (C2+) products is of great *** we developed a nitrogen-doped Cu catalyst,by which the maximum C2+Faradaic efficiency can reach 72.7%in flow-cell system,with the partial current density reaching 0.62 A *** in situ Raman spectra demonstrate that the *CO adsorption can be strengthened on such a N-doped Cu catalyst,thus promoting the*CO utilization in the subsequent C–C coupling ***,the water activation can be well enhanced by N doping on Cu *** to the synergistic effects,the selectivity and activity for C2+products over the N-deoped Cu catalyst are much improved.

关键词： Electrocatalytic CO 2 reduction reaction Copper catalyst Doping Multi-carbon products In situ Raman measurement