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China Foundry 2018年第1期15卷 51-57页

作者： Chen-guang Liu Yun-song zhao Jian Zhang Ding-zhong Tang Chun-zhi Li zhen-ye zhao Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

In this study, the long-term thermal microstructural stability and related stress rupture lives of a new Re-containing Ni-based single-crystal superalloy, DD11, were investigated after high-temperature exposure for different lengths of time. The results show that the γ' precipitates retained a cuboidal morphology and the γ' size increased after short thermal exposure for 50 h at 1,070℃. As the thermal exposure time was prolonged to 500 h, the cuboidal γ' gradually changed into irregular raft-like morphology due to particles coalescence, and the morphology of the microstructure was almost unchanged after further thermal exposure up to 3,000 h. The stress rupture experiments at 1,070℃ and a tensile stress of 140 MPa showed that the rupture lives increased significantly after thermal exposure for 50 h and dropped dramatically with increasing exposure time up to 500 h but decreased slowly after exposure for more than 500 h. These results imply that stress rupture properties did not decrease when the γ' remained cuboidal but degraded to different extents during the γ' coarsening process. The coarsening of the γ' precipitates and change in morphology were regarded as the main factors leading to the degradation of the stress rupture lives. This study provides fundamental information on the high-temperature longterm microstructural stability and mechanical performance, which will be of great help for DD11 alloy optimization and engineering aeroengine applications.

关键词： Ni-based superalloy thermal exposure microstructure coarsening stress-rupture properties

Synergistic effects of the entomopathogenic fungus Isaria javanica and low doses of dinotefuran on the efficient control of the rice pest Sogatella furcifera

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Journal of Integrative Agriculture 2024年第2期23卷 621-638页

作者： Tingting Zhou Qian zhao Chengzhou Li Lu ye Yanfang Li Nemat OKeyhani zhen Huang Department of Entomology College of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Key Laboratory of High Technology for Plant Protection Plant Protection Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510642China Department of Microbiology and Cell Science Institute of Food and Agricultural SciencesUniversity of FloridaFL 32611USA

The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza *** is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical *** investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on *** under both laboratory and field *** results show that *** displays high infection efficiency and mortality for different stages of ***,reducing adult survival,female oviposition and ovary *** bioassays showed that the combined use of *** with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in *** than the use of *** or dinotefuran *** combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase *** field trials,*** effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of *** populations using the combination of a low dose of ***(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days *** findings indicate that the entomogenous fungus *** offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.

关键词： Isaria javanica Sogatella furcifera entomopathogenic fungus white planthopper rice synergistic effect on pest control

Effects of synthetic site water on bentonite-concrete system for a potential nuclear waste repository

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3786-3797页

作者： zhao Sun Yong-Gui Chen Wei-Min ye Qiong Wang Dong-Bei Wu zhen-Yu Yin Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Department of Geotechnical EngineeringTongji UniversityShanghai200092China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina School of Chemical Science and Engineering Tongji UniversityShanghai200092China

In high-level nuclear waste(HLW)repositories,concrete and compacted bentonite are designed to be employed as buffer materials,which may raise a problem of interactions between concrete and *** interactions would lead to mineralogy transformation and buffer performance decay of bentonite under the near field environment conditions in a repository.A small-scale experimental setup was established to simulate the concrete-bentonite-site water interaction system from a potential nuclear waste repository in *** types of mortars were prepared to correspond to the concrete at different degradation *** results permit the determination of the following:(1)The macroproperties of Gaomiaozi(GMZ)bentonite(*** pressure,permeability,the final dry density,and water content of reacted samples);(2)The composition evolution of fluids from the synthetic site water-concrete-bentonite interaction systems;(3)The sample characterization including Fourier transform infrared spectroscopy(FTIR)and X-ray powder diffraction(XRD).Under the infiltration of the synthesis Beishan site water(BSW),the swelling pressure of bentonite decreases slowly with time after reaching its second swelling *** flux decreases with time during the infiltrations,and it tends to be stable after more than 120 *** to the cation exchange reactions in the BSW-concrete-bentonite systems,the divalent cations(Ca and Mg)were consumed,and the monovalent cations(Na and K)were *** dissolution of minerals in the bentonite such as albite causes Si increasing in the pore *** was concluded that the hydro-mechanical property degradation of bentonite takes place when it comes into contact with concrete mortar,even under low-pH groundwater *** soil dispersion,the uneven water content,and the uneven dry density in bentonite samples may partly contribute to the swelling decay of ***,the direct contact with concrete has an obvious effect on the performance

关键词： Mock-up device GMZ bentonite Site water-concrete-bentonite system Geochemistry Buffer performance

Nitro-oleic acid ameliorates erectile dysfunction in a streptozotocin-induced rat model of diabetes by inhibiting oxidative stress and apoptosis and activating the NO/cGMP pathway

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Asian Journal of Andrology 2024年第1期26卷 57-66页

作者： Chang-Bo zhao Wei-Bo Chen Wen-zhen Wang Fang-Xin Gong Cui-Qin Fan ye Li Tian Lan Wen-Jing Wang Ming-zhen Yuan Department of Urology Shandong Provincial HospitalShandong UniversityJinan 250012China Department of Andrology Liaocheng People's HospitalShandong UniversityLiaocheng 252000China Department of Urology The Second Hospital of Shandong UniversityJinan 250012China Department of Physiology School of Basic Medical SciencesShandong UniversityJinan 250012China

The major vascular complications associated with diabetes make the management of diabetic mellitus erectile dysfunction(DMED)a challenging *** factors contributing to DMED include oxidative stress,nitric oxide(NO)/cyclic guanosine monophosphate(cGMP)pathway activation,and apoptosis,while nitro-oleic acid(NO,-OA)has been shown to be beneficial in treating these aspects of this ***,herein,investigated the effects and possible mechanisms of NO,-OA on erectile function as assessed in a streptozotocin-induced rat model of *** results revealed that the erectile function of DMED rats was significantly impaired compared with that of the control ***,in response to 4 weeks of NO,-OA treatment,there was an improvement in erectile *** expression of oxidative stress-related indicators was significantly increased and the NO/cGMP pathway was impaired in the DMED *** expression of proapoptotic factors was increased,while that of antiapoptotic factors was decreased in the DMED ***,the cell morphology in the cavernous tissue of the DMED group also changed ***,-OA treatment significantly reversed all these changes observed in the DMED *** conclusion,NO,-OA treatment partially improved erectile function in DMED rats through mechanisms that included inhibition of oxidative stress,activation of the NO/cGMP pathway,and a reduction in apoptosis.

关键词： apoptosis diabetic mellitus erectile dysfunction nitro-oleic acid NO/cGMP pathway oxidative stress

Transforming liquid flow fuel cells to controllable reactors for highlyefficient oxidation of 5-hydroxymethylfurfural to 2, 5-furandicarboxylic acid at low temperature

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Journal of Energy Chemistry 2024年第3期90卷 621-631,I0014页

作者： ye Qiang Xi Liu Denghao Ouyang zhao Jiang Xuebing zhao Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Institute of Applied Chemistry Department of Chemical EngineeringTsinghua UniversityBeijing 100084China School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina

Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still ***,inspired by the respirato ry electron transport chain(ETC) of living cells mediated by electron carriers,we constructed artificial ETCs and transformed liquid flow fuel cells(LFFCs) to flexible reactors for efficient oxidation of HMF to produce FDCA under mild *** LFFC reactor employed an electrodeposition modified nickel foam as an anode to promote HMF oxidation and(VO_(2))_(2)SO_(4) as a cathode electron carrier to facilitate the electron transfer to *** reaction rate could be easily controlled by selecting the anode catalyst,adjusting the external loading and changing the cathodic electron carrier or oxidants.A maximal power density of 44.9 mW cm^(-2) at room temperature was achieved,while for FDCA production,short-circuit condition was preferred to achieve quick transfer of *** a single batch operation with 0.1 M initial HMF,FDCA yield reached 97.1%.By fed-batch operation,FDCA concentration reached 144.5 g L^(-1) with a total yield of 96%.Ni^(2+)/Ni^(3+) redox couple was the active species mediating the electron transfer,while both experimental and DFT calculation results indicated that HMFCA pathway was the preferred reaction mechanism.

关键词： 5-Hydroxymethylfurfural 2 5-Furandicarboxylic acid Electrodeposition Electron transport chain Liquid flow fuel cell

Amino acids TORC(talk)to anabolism through uncharged tRNA

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Science China(Life Sciences) 2024年第8期67卷 1775-1776页

作者： zhen-zhen Ma Shi-Min zhao The Obstetrics&Gynecology Hospital of Fudan University State Key Laboratory of Genetic EngineeringShanghai Key Laboratory of Metabolic Remodelling and HealthFudan UniversityShanghai 200090China

Anabolism is essential for proliferation as well as to replenish dysfunctional macromolecules in *** to that both substantial building blocks and energy are required for anabolism,cells must double check whether these prerequisites are met before deciding to start *** acids are building blocks of protein synthesis,their sufficiency in cells is closely monitored by several mechanisms,which all are linked to protein synthesis.

关键词： synthesis. synthesis deciding

Rotor cross-tilt optimization for yaw control improvement of multi-rotor eVTOL aircraft

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Chinese Journal of Aeronautics 2024年第3期37卷 153-167页

作者： Xufei YAN ye YUAN Yanqin zhao Renliang CHEN Zhejiang Lab Hangzhou 311100China Department of Aerospace Engineering Swansea UniversitySwanseaWales SA28PPUK National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Manned multi-rotor electric Vertical Takeoff and Landing(eVTOL)aircraft is prone to actuator saturation due to its weak yaw control *** address this inherent problem,a rotor cross-tilt configuration is applied in this paper,with an optimization method proposed to improve the overall control efficiency of the ***,a flight dynamics model of a 500-kg manned multi-rotor eVTOL aircraft is *** accuracy of the co-axial rotor model is verified using a single arm test bench,and the accuracy of the flight dynamics model is verified by the flight test ***,an optimization method is designed based on the flight dynamics model to calculate an optimal rotor cross-tilt mounting angle,which not only improves the yaw control efficiency,but also basically maintains the efficiency of other control *** ideal rotor cross-tilt mounting angle for the prototype is determined by comprehensively considering the optimal results with different payloads,forward flight speeds,and rotor mounting angle ***,the feasibility of the rotor cross-tilt mounting angle is proved by analyzing the control derivatives of the flight dynamics model,the test data of a ground three Degree-of-Freedom(3DOF)platform,and the actual flight data of the *** results show that a fixed rotor cross-tilt mounting angle can achieve ideal yaw control effectiveness,improving yaw angle tracking and hold ability,increasing endurance time,and achieving good yaw control performance with different payloads and forward speeds.

关键词： Multi-rotor eVTOL Control efficiency Flight dynamics model Cross-tilt optimization Endurance time

Emerging interactively stretchable electronics with optical and electrical dual-signal feedbacks based on structural color materials

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Nano Research 2024年第3期17卷 1837-1855页

作者： Jialin Wang Kai zhao Changqing ye Yanlin Song School of Materials Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of SciencesBeijing 100190China

The booming development of wearable devices has aroused increasing interests in flexible and stretchable *** mechanosensory functionality,these devices are highly desirable on account of their wide range of applications in electronic skin,personal healthcare,human–machine interfaces and ***,they are mostly limited by single electrical signal feedback,restricting their diverse applications in visualized mechanical *** by the mechanochromism of structural color materials,interactively stretchable electronics with optical and electrical dual-signal feedbacks are recently emerged as novel sensory platforms,by combining both of their sensing mechanisms and ***,recent studies on interactively stretchable electronics based on structural color materials are *** a brief introduction of their basic components(i.e.,stretchable electronics and mechanochromic structural color materials),two types of interactively stretchable electronics with respect to the nanostructures of mechanochromic materials are outlined,focusing primarily on their design considerations and fabrication ***,the main challenges and future perspectives of these emerging devices are discussed.

关键词： stretchable electronics structural color materials interactive sensing mechanochromism dual-signal feedbacks

Direct ink writing of multifunctional gratings with gel-like MXene/norepinephrine ink for dynamic electromagnetic interference shielding and patterned Joule heating

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Nano Research 2024年第3期17卷 1585-1594页

作者： Pei-Zhu Jiang Zhiming Deng Peng Min Lvxuan ye Cheng-Zhang Qi Hao-Yu zhao Ji Liu Hao-Bin Zhang Zhong-zhen Yu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China School of Chemistry CRANN and AMBERTrinity College DublinDublin D02PN40Ireland

Intelligent electromagnetic interference(EMI)shielding modulators with a wide tuning range and cyclic stability are urgently needed but their fabrication remains challenging.A gel-like MXene/norepinephrine ink is developed and multifunctional MXene gratings with wide EMI shielding effectiveness(SE)tuning range,superior reversibility,and high mechanical flexibility are constructed by direct ink writing approach for dynamic EMI shielding and patterned Joule heating *** modulable MXene/norepinephrine grating with a high conductivity of 3510 S·cm-1 can conveniently realize the seamless modulation of the EMI SE by adjusting the angle between the MXene grating filaments and the electric field of the incident electromagnetic waves,offering highly reversible switching between shielding“On”(28.0 dB)and“Off”(0.5 dB)***,due to the optimized integration of the MXene ink and the rationally designed pattern,a superior specific EMI SE of 95,688.2 dB·cm^(2)·g^(-1) is achieved in the“On”***,the MXene/norepinephrine ink can be used to fabricate many complex patterned gratings with superior stability,instant responsibility,and superb mechanical flexibility,exhibiting a unique patterned Joule heating *** writing of multifunctional gratings paves a means for developing intelligent EMI shielding materials,wearable electronic devices,and advanced thermal management materials.

关键词： MXene ink direct ink writing electromagnetic interference shielding multifunctional gratings Joule heating

A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network

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China Communications 2024年第2期21卷 122-128页

作者： Xiao Li Ling zhao zhen Dai Yonggang Lei School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Beijing Institute of Tracking and Telecommunications Technology BITTT

This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1dB improvement compared to Fully Convolutional Networks(FCN).

关键词： belief propagation channel decoding correlated noise neural network