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Potassium alleviated high nitrogen-induced apple growth inhibition by regulating photosynthetic nitrogen allocation and enhancing nitrogen utilization capacity

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Horticultural Plant Journal 2024年第1期10卷 1-14页

作者： Xinxiang Xu Guangyuan liu Jingquan liu mengxue Lyu Fen Wang yue Xing Hao meng Min Li Yu Jiang Ge Tian Zhanling Zhu Yuanmao Jiang Shunfeng Ge State Key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China Key Laboratory of Biochemistry and Molecular Biology in Universities of Shandong College of Biological and Agricultural EngineeringWeifang UniversityWeifangShandong 261061China

There is a close relationship between potassium(K)and nitrogen(N).However,the roles of K under high N conditions remain *** a hydroponics approach,we monitored the morphological,physiological,and molecular changes in M9T337 apple(Malus domestica)rootstocks under different nitrate(10 and 30 mmol·L^(-1)NO_(3)^(-))and K supply(0.5,6,10,and 20 mmol·L_(-1)K^(+))*** revealed that high nitrate inhibited the root growth of M9T337 rootstocks,downregulated the expressions of K transporter genes(MdPT5,MdHKT1,and MdATK1),and reduced the net NO3-and K+influx at the surface of roots,thereby resulting in an N/K imbalance in *** investigation showed that 10 mmol·L^(-1)K increased the activity of N metabolic enzymes(NR,GS,NiR,and GOGAT),upregulated the expressions of genes related to nitrate uptake and transport(MdNRT1.1,MdNRT1.2,MdNRT1.5,and MdNRT2.4),promoted15N transport from the roots to the shoots,optimized leaf N distribution,and improved photosynthetic N utilization efficiency under high nitrate *** results suggest that the negative effects of high nitrate may be related to the N/K imbalance and that reducing N/K in plants by increasing K supply level can effectively alleviate the inhibition of N assimilation by high nitrate stress.

关键词： Apple rootstock K level High nitrate stress N metabolism ^(15)N

Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel

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Petroleum Science 2024年第2期21卷 1275-1289页

作者： Qian Li Zi-Jie Lin liu Yang yue Wang yue Li Wei-Hua Cai Laboratory of Thermo-Fluid Science and Nuclear Engineering Northeast Electric Power UniversityJilin132000JilinChina School of Energy and Power Engineering Northeast Electric Power UniversityJilin132000JilinChina

The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 *** simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow *** results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were *** calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So hea

关键词： Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis

CuInS_(2)quantum-dot-modified g-C_(3)N_(4)S-scheme heterojunction photocatalyst for hydrogen production and tetracycline degradation

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Journal of Materials Science & Technology 2024年第5期172卷 145-155页

作者： Jingjing Zhang yue Zhao Kezhen Qi Shu-yuan liu College of Pharmacy Dali UniversityDali 671000China Department of Pharmacology Shenyang Medical CollegeShenyang 110034China

CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth *** as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption *** photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light *** optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN *** enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional *** work is an effort to adjust CN-based polysulfide QD for speedy *** enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.

关键词： CuInS_(2)QDs g-C_(3)N_(4) Photocatalysis Hydrogen production S-scheme heterojunction

Fast and Adaptive Multi-Agent Planning under Collaborative Temporal Logic Tasks via Poset Products

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Research 2024年第2期2024卷 81-94页

作者： Zesen liu meng Guo Weimin Bao Zhongkui Li Deparment of Mechanics and Engineering Science College of EngineeringPeking UniversityBejing 0081 China Science and Technology Commission of China Aerospace Science and Technology Corporation Beijing 100048China

Efficient coordination and planning is essential for large-scale multi-agent systems that collaborate in a shared dynamic environment. Heuristic search methods or learning-based approaches often lack the guarantee on correctness and performance. Moreover, when the collaborative tasks contain both spatial and temporal requirements, e.g., as linear temporal logic (LTL) formulas, formal methods provide a verifiable framework for task planning. However, since the planning complexity grows exponentially with the number of agents and the length of the task formula, existing studies are mostly limited to small artificial cases. To address this issue, a new planning paradigm is proposed in this work for system-wide temporal task formulas that are released online and continually. It avoids two common bottlenecks in the traditional methods, i.e., (a) the direct translation of the complete task formula to the associated B點hi automaton and (b) the synchronized product between the B點hi automaton and the transition models of all agents. Instead, an adaptive planning algorithm is proposed, which computes the product of relaxed partially ordered sets (R-posets) on-the-fly and assigns these subtasks to the agents subject to the ordering constraints. It is shown that the first valid plan can be derived with a polynomial time and memory complexity with respect to the system size and the formula length. Our method can take into account task formulas with a length of more than 400 and a fleet with more than 400 agents, while most existing methods fail at the formula length of 25 within a reasonable duration. The proposed method is validated on large fleets of service robots in both simulation and hardware experiments.

关键词： hardware service system

Nacre-inspired MXene-based film for highly sensitive piezoresistive sensing over a broad sensing range

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Bio-Design and Manufacturing 2024年第4期7卷 463-475页

作者： Gaofeng Wang Lingxian meng Xinyi Ji Xuying liu Jiajie Liang Shuiren liu School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China School of Materials Science and Engineering National Institute for Advanced MaterialsNankai UniversityTianjin 300350China

As the main component of wearable electronic equipment,flexible pressure sensors have attracted wide attention due to their excellent sensitivity and their promise with respect to applications in health monitoring,electronic skin,and human-computer ***,it remains a significant challenge to achieve epidermal sensing over a wide sensing range,with short response/recovery time and featuring seamless conformability to the skin *** is critical since the capture of minute electrophysiological signals is important for health care *** this paper,we report the preparation of a nacre-like MXene/sodium carboxymethyl cellulose(CMC)nanocomposite film with a“brick-and-mortar”interior structure using a vacuum-induced self-assembly *** synergistic behavior of the MXene“brick”and flexible CMC“mortar”contributes to attenuating interlamellar self-stacking and creates numerous variable conductive pathways on the sensing *** resulted in a high sensitivity over a broad pressure range(i.e.,0.03-22.37 kPa:162.13 kPa^(-1);22.37-135.71 kPa:127.88 kPa^(-1);135.71-286.49 kPa:100.58 kPa^(-1)).This sensor also has a low detection limit(0.85 Pa),short response/recovery time(8.58 ms/34.34 ms),and good stability(2000 cycles).Furthermore,we deployed pressure sensors to distinguish among tiny particles,various physiological signals of the human body,space arrays,robot motion monitoring,and other related applications to demonstrate their feasibility for a variety of health and motion monitoring use cases.

关键词： Flexible pressure sensor MXene Bioinspired Physiological signals Interlayer spacing

Recent breakthrough in AI-driven materials science:tech giants introduce groundbreaking models

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Materials Futures 2024年第2期3卷 170-174页

作者： Miao liu Sheng meng Institute of Physics Chinese Academy of SciencesBeijing 100190People’s Republic of China Songshan Lake Materials Laboratory DongguanGuangdong 523808People’s Republic of China

A close look at Google’s GNoME inorganic materials dataset(Merchant et al 2023 Nature 62480–85),and 11 things you would like to know.

关键词： AI GNoME dataset AI+materials science

Safety,immunogenicity and protective effect of sequential vaccination with inactivated and recombinant protein COVID-19 vaccine in the elderly:a prospective longitudinal study

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2738-2747页

作者： Hong-Hong liu Yunbo Xie Bao-Peng Yang Huan-yue Wen Peng-Hui Yang Jin-E Lu Yan liu Xi Chen meng-meng Qu Yang Zhang Wei-Guo Hong Yong-Gang Li Junliang Fu Fu-Sheng Wang Out-patient Department of Day Diagnosis and Treatment The Fifth Medical Center of Chinese PLA General HospitalBeijing 100039China Senior Department of Infectious Diseases The Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China Chinese PLA Medical School Chinese PLA General HospitalBeijing 100039China Hunyuan County People’s Hospital Datong 037499 Shanxi ProvinceChina Faculty of Hepato-Pancreato-Biliary Surgery Institute of Hepatobiliary SurgeryThe First Medical CenterChinese PLA General HospitalBeijing 100853China

The safety and efficacy of COVID-19 vaccines in the elderly,a high-risk group for severe COVID-19 infection,have not been fully *** clarify these issues,this prospective study followed up 157 elderly and 73 young participants for 16 months and compared the safety,immunogenicity,and efficacy of two doses of the inactivated vaccine BBIBP-CorV followed by a booster dose of the recombinant protein vaccine *** results showed that this vaccination protocol was safe and tolerable in the *** administering two doses of the BBIBP-CorV,the positivity rates and titers of neutralizing and anti-RBD antibodies in the elderly were significantly lower than those in the young *** the ZF2001 booster dose,the antibody-positive rates in the elderly were comparable to those in the young;however,the antibody titers remained ***,age,and underlying diseases were independently associated with vaccine immunogenicity in elderly *** pseudovirus neutralization assay showed that,compared with those after receiving two doses of BBIBP-CorV priming,some participants obtained immunological protection against BA.5 and BF.7 after receiving the ZF2001 *** infection symptoms last longer in the infected elderly and pre-infection antibody titers were negatively associated with the severity of post-infection *** antibody levels in the elderly increased significantly after breakthrough infection but were still lower than those in the *** data suggest that multiple booster vaccinations at short intervals to maintain high antibody levels may be an effective strategy for protecting the elderly against COVID-19.

关键词： vaccination vaccine doses

Development of a deviation package method for low-cost robust optimization in compressor blade design

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Chinese Journal of Aeronautics 2024年第4期37卷 166-180页

作者： Mingzhi LI Xianjun YU Dejun meng Guangfeng AN Baojie liu Research Institute of Aero-Engine Beihang UniversityBeijing 100191China National Key Laboratory of Science&Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China AECC Shenyang Engine Research Institute Shenyang 110015China

Manufacture variations can greatly increase the performance variability of compressor blades. Current robust design optimization methods have a critical role in reducing the adverse impact of the variations, but can be affected by errors if the assumptions of the deviation models and distribution parameters are inaccurate. A new approach for robust design optimization without the employment of the deviation models is proposed. The deviation package method and the interval estimation method are exploited in this new approach. Simultaneously, a stratified strategy is used to reduce the computational cost and assure the optimization accuracy. The test case employed for this study is a typical transonic compressor blade profile, which resembles most of the manufacture features of modern compressor blades. A set of 96 newly manufactured blades was measured using a coordinate measurement machine to obtain the manufacture variations and produce a deviation package. The optimization results show that the scatter of the aerodynamic performance for the optimal robust design is 20% less than the baseline value. By comparing the optimization results obtained from the deviation package method with those obtained from widely-used methods employing the deviation model, the efficiency and accuracy of the deviation package method are demonstrated. Finally, the physical mechanisms that control the robustness of different designs were further investigated, and some statistical laws of robust design were extracted.

关键词： Manufacture variations Robust design optimization Compressor leading edge Aerodynamics Physical mechanism

An efficient stiffness analysis model based on shear deformation theory for flexible skin shear variable-sweep wing

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Chinese Journal of Aeronautics 2024年第10期37卷 445-458页

作者： yue BAI Guang YANG Hong XIAO Hongwei GUO Rongqiang liu Bei liu State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China China Aerodynamics Research and Development Center Institute of High-Speed AerodynamicsMianyang 621000China

Fixed-wing aircraft cannot maintain optimal aerodynamic performance at different flight *** a type of morphing aircraft,the shear variable-sweep wing(SVSW)can dramatically improve its aerodynamic performance by altering its shape to adapt to various flight *** order to achieve smooth continuous shear deformation,SVSW’s skin adopts a flexible composite skin design instead of traditional aluminum alloy ***,this also brings about the non-linear difficulty in stiffness modeling and *** this research,a new SVSW design and efficient stiffness modeling method are *** on shear deformation theory,the flexible composite skin is equivalently modeled as diagonally arranged nonlinear springs,simulating the elastic force interaction between the skin and the *** shear loading tests of flexible composite skin,the accuracy of this flexible composite skin modeling method is *** SVSW stiffness model was established,and its accuracy was verified through static loading *** effects of root connection,sweep angles,and flexible composite skin on the SVSW stiffness are ***,considering three typical flight conditions of SVSW:low-speed flow(Ma=0.3,Re=5.8210^(6)),transonic flow(Ma=0.9,Re=3.4410^(6)),and supersonic flow(Ma=3,Re=7.5110^(6)),the stiffness characteristics of SVSW under flight conditions were *** calculated results guide the application of SVSW.

关键词： Shear variable-sweep wing(SVSW) Flexible composite skin Morphing mechanism Stiffness analysis Loading tests Structure