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A Single-Event-Transient Hardened Phase Locked Loop for Clock and Data Recovery

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Chinese Journal of Electronics 2024年第2期33卷 353-361页

作者： Hengzhou YUAN Bin LIANG Hao SANG Weixia XU Yang GUO xi chen National University of Defense Technology

A radiation-hardened phase-locked loop is proposed for phase interpolator clock and data recovery purposes. A sensitive node-compressed charge pump and multi-node cross coupling voltage-controlled oscillators are proposed in this phase-locked loop with the goal of achieving good jitter performance and improving anti-SET（SET,single-event transient） capability. The root mean square（RMS） jitter of the phase-locked loop is reduced from 3.7 ps to 2.58 ps at 2 GHz, while the laser threshold is improved from 120 p J to 370 p J compared to the unhardened phaselocked loop. The hardened phase-locked loop also does not lose its lock state from linear energy transfers（LETs） of 3.3 to 37.3 Me V·cm2/mg.

关键词： Charge pumps Voltage-controlled oscillators Energy exchange Noise Lasers Jitter Phase locked loops

Fine-tuning growth in gold nanostructures from achiral 2D to chiral 3D geometries

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Nano Research 2024年第7期17卷 6654-6660页

作者： Lili Tan Zhi chen chengyu xiao Zhiyong Geng Yinran Jin Chaoyang Wei Fei teng Wenlong Fu Peng-peng Wang State Key Laboratory for Mechanical Behavior of Materials Shaanxi International Research Center for Soft MatterSchool of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China

Enriching the library of chiral plasmonic structures is of significant importance in advancing their applicability across diverse domains such as biosensing,nanophotonics,and ***,employing triangle nanoplates as growth seeds,we synthesized a novel class of chiral-shaped plasmonic nanostructures through a wet chemical strategy with dipeptide as chiral inducers,including chiral tri-blade boomerangs,concave rhombic dodecahedrons,and *** structural diversity in chiral plasmonic nanostructures was elucidated through their continuous morphological evolution from two-dimensional to threedimensional *** fine-tuning of chiroptical properties was achieved by precisely manipulating crucial synthetic parameters such as the amount of chiral molecules,seeds,and gold precursor that significantly influenced chiral structure *** findings provide a promising avenue for enriching chiral materials with highly sophisticated structures,facilitating a fundamental understanding of the relationship between structural nuances and chiroptical properties.

关键词： plasmonic nanostructures geometric chirality circular dichroism fine-tuning

Effects of zeolite imidazole frameworks on rice seedlings (Oryza sativa L.): Phytotoxicity, transformation, and bioaccumulation

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Journal of Environmental Sciences 2024年第10期144卷 15-25页

作者： Chaofa chen Yongqi Yao chenghua xing Yunyu Guo Luyi Cai Jianfang Yan xi-Lin Wu Miaozhen Cai College of Geography and Environmental Science Zhejiang Normal UniversityJinhuaZhejiang 321004China College of Agriculture Jinhua PolytechnicJinhuaZhejiang 321007China

Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental ***,their environmental fate and potential ecological impact on plants remain ***,we investigated the phytotoxicity,transformation,and bioaccumulation processes of two typical ZIFs(ZIF-8 and ZIF-67)in rice(Oryza sativa L.)under hydroponic ***-8 and ZIF-67 in the concentration of 50 mg/L decreased root and shoot dry weight maximally by 55.2%and 27.5%,53.5%and 37.5%,*** scanning electron microscopy(SEM)imaging combined with X-ray diffraction(XRD)patterns revealed that ZIFs on the root surface gradually collapsed and transformed into nanosheets with increasing cultivation *** fluorescein isothiocyanate(FITC)labeled ZIFs were applied to trace the uptake and translocation of ZIFs in *** results demonstrated that the transformed ZIFs were mainly distributed in the intercellular spaces of rice root,while they cannot be transported to culms and *** so,the Co and Zn contents of rice roots and shoots in the ZIFs treated groups were increased by 1145%and 1259%,145%and 259%,respectively,compared with the control *** findings suggested that the phytotoxicity of ZIFs are primarily attributed to the transformed ZIFs and to a less extent,the metal ions and their ligands,and they were internalized by rice root and increased the Co and Zn contents of *** study reported the transformation of ZIFs and their biological effectiveness in rice,highlighting the potential environmental hazards and risks of ZIFs to crop plants.

关键词： Zeolitic imidazolate frameworks (ZIFs) Rice(Oryza sativa L.) Phytotoxicity Transformed ZIFs ZIFs bioaccumulation

Research on feed-pulse collaborative control method in micro-electrical discharge machining

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Advances in Manufacturing 2024年第2期12卷 270-287页

作者： Qiang Gao Ya-Ou Zhang Xue-cheng xi Yuan-Ding Wang xiao-Fei chen Wan-Sheng Zhao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China State Key Laboratory of Mechanical System and Vibration Shanghai200240People’s Republic of China Shanghai Institute of Space Propulsion Shanghai201112People’s Republic of China

Reducing the short-circuit rate and increasing the effective discharge rate are important targets for improving the servo control effect of micro-electrical discharge machining(micro-EDM),as these two indicators are closely related to the machining efficiency and *** this study,a feed-pulse collaborative control(FPCC)method is proposed for micro-EDM based on two dimensions(space and time).In the spatial dimension,a feed control strategy with a discharge holding process is ***,in the time dimension,a forward-looking pulse control strategy is adopted,in which the pulse interval is adjusted based on a sequence analysis of feed commands and discharge *** experiments are carried out to determine the key parameters used in this method,including the discharge holding threshold and pulse interval adjustment value(T_(off_(adj))).The feed smoothness and discharge sufficiency analyses of the experimental results show that compared to the traditional double threshold average voltage method,the FPCC method reduces the number of long-distance retreats by 64%and improves the effective discharge time by 40%.

关键词： Micro-electrical discharge machining(micro-EDM) Electrode feed control Discharge pulse control Machining surface quality

Strengthening effect of prefabrication(10-12)tensile twinning on AZ80+0.4%Ce magnesium alloy and inhibition mechanism of discontinuous precipitation

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Journal of Magnesium and Alloys 2024年第5期12卷 1918-1930页

作者： Zhen Wang xi Zhao Zhimin Zhang Yaojin Wu Kai chen xianwei Ren Dengkui Wang Wei Wang School of Mechanical and Electrical Engineering North University of ChinaTaiyuan 030051China Engineering Technology Research Center for Integrated Precision Forming of Shanxi Province North University of ChinaTaiyuan 030051China

This paper provided an effective method to further improve the mechanical properties of the AZ80+0.4%Ce magnesium alloy wheel *** effect of high strength and ductility was obtained with a yield strength of 295.36 MPa,an elongation of 10%,by the combination of pre-deformation(7%deformation)and two-stage aging treatment(120℃/9 h+175℃/24 h).The evolution of the microstructure and properties of the alloy was explored under the coupling conditions of different pre-deformation degrees and multi-stage *** results show that,pre-deformation introduced a large number of(1012)tensile twinning and dislocations,which greatly promoted the probability of continuous precipitates(CPs)*** the contrary,the discontinuous precipitates(DPs)were limited by the vertical and horizontal twin *** a result,the pre-nucleation method of two-stage aging increased the proportion of CPs by 34%-38%.Owing to the DPs was effectively suppressed,the alloy's yield strength has been greatly ***,under multi-stage aging,the twin boundaries induce protruding nucleation to form static recrystallization by hindering the migration of dislocations,and the matrix swallows the twins,then the texture gradually tilts from the two poles to the basal *** an important supplement,the grain refinement and oblique texture promoted the improvement of the yield strength of the component.

关键词： Magnesium alloy Pre-deformed Two-stage aging Tensile twinning Continuous precipitates Texture

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RpUGT344J7 is involved in the reproduction switch of Rhopalosiphum padi with holocyclic life cycle

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Insect Science 2024年第4期31卷 1073-1089页

作者： Suji Wang Wenjie Huang Mengtian Li Ni Wang xi Liu Maohua chen xiong Peng State Key Laboratory of Crop Stress Biology for Arid Areas Key Laboratory of Plant Protection Resources and Pest Management of Ministry of EducationKey Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture and Rural AffairsCollege of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi ProvinceChina

Many aphid species exhibit both cyclical parthenogenesis(CP)and the obligate parthenogenesis(OP)life history,which are genetically *** CP aphid lineages,the parthenogenetic individuals can switch from asexual to sexual reproduction quickly in response to environmental factors such as changes in photoperiod and ***,the OP aphid lineages do not undergo sexual reproduction under any *** far,mechanisms underlying the reproduction switch in CP aphids have not been fully *** padi,a serious worldwide insect pest of wheat,has both CP and OP *** diphosphate-glycosyltransferases(UGTs)are enzymes that participate in the metabolic detoxification of ***,we identified 43 RpUGT genes from *** genome and transcriptome sequences,and found that:(1)the UGT content of the CP lineage was significantly higher than that in the OP lineage at the key time points when CP lineage mainly produce virginoparae,gynoparae,and males under inducing condition,while there were no significant difference under normal conditions;(2)RpUGT344J7 gene was highly expressed during the time points when CP lineages produce gynopara and males;(3)the critical time points for CP lineages to produce virginoparaee,gynoparae,and males were affected when the CP lineages were injected with dsRpUGT344J7;(4)the knockdown of RpUGT344J7 caused a significant reduction in the total number of virginoparae,gynoparae,and males in the offspring under inducing *** findings contribute to our understanding of the molecular mechanisms underlying the quick shift from asexual to sexual reproduction in aphid species.

关键词： bird cherry-oat aphid cyclical parthenogenesis obligate parthenogenesis reproduction switch uridine diphosphate-glycosyltransferases(UGTs)

Tungsten pnictides for water electrolysis:advances and perspectives

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Tungsten 2024年第4期6卷 675-695页

作者： Xue Kang xi-Han Tan Ning Han Jian-Feng Hou chen-Min Yao Zhi-Jie chen Bing-Jie Ni Department of Chemistry and Chemical Engineering Lyuliang University Department of Materials Engineering State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of Education Hubei Key Laboratory of Stomatology School & Hospital of Stomatology Wuhan University School of Civil and Environmental Engineering The University of New South Wales

Hydrogen fuel is recognized as a promising energy carrier for the sustainable development of global energy system and the green hydrogen production via water electrolysis attracts great *** development of cost-effective electrocatalysts for water electrolysis is important for enhancing green hydrogen production ***,tungsten pnictides(phosphides and nitrides) have emerged as promising catalysts for water electrolysis,and efficient tungsten pnictide-based catalysts with different nanostructures,compositions,and surface chemical properties have been *** this review,recent progress in the design of tungsten pnictide-based electrocatalysts for water electrolysis is comprehensively *** synthesis of tungsten pnictide-based electrocatalysts are discussed ***,current achievements in developing efficient tungsten pnictide electrocatalysts for water electrolysis are detailed,and four key catalyst design strategies(i.e.,nanostructure control,heteroatom doping,defect engineering,and heterostructure design) are *** physicochemical properties-catalytic performance relationship of tungsten pnictide-based electrocatalysts is also *** last,perspectives in this field are put forward for guiding further research on the design and application of high-performance tungsten pnictide-based electrocatalysts.

关键词： Electrocatalysts Hydrogen evolution reaction Oxygen evolution reaction Tungsten nitrides Tungsten phosphides

Preparation and Analysis of Carbon Fiber-Silicon Carbide Thermally Conductive Asphalt Concrete

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Fluid Dynamics & Materials Processing 2024年第4期20卷 705-723页

作者： Zhiyong Yang Enjie Hu Lei xi Zhi chen Feng xiong Chuanhai Zhan School of Civil Engineering and Environment Hubei University of TechnologyWuhan430068China

An experimental investigation into the thermal conductivity of CF-SiC two-phase composite asphalt concrete is *** main objective of this study was to verify the possibility of using SiC powder instead of mineral powder as the thermal conductive filler to prepare a new type of asphalt concrete and improve the efficiency of electrothermal snow and ice melting systems *** thermal conductivity of asphalt concrete prepared with different thermally conductive fillers was tested by a transient plane source method,and the related performances were *** the temperature rise rate and surface temperature were studied through field heating ***,the actual ice melting efficiency of the thermally conductive asphalt concrete was evaluated using an effective electrothermal *** shown by the experimental results,the composite made of SiC powder and carbon fiber has a high thermal *** SiC replaces mineral powder,the thermal conductivity of the asphalt mixture increases first and then decreases with the increase of carbon fiber *** the present study,in particular,the thermal conductivity attained a peak when the carbon fiber content was 0.2%of the aggregate mass.

关键词： Carbon fiber silicon carbide thermally conductive asphalt concrete road performance electrothermal snow melting

Selective synthesis of the B_(11)H_(14)^(-) and B_(12)H_(12)^(2-) borane derivatives and the general mechanisms of the B-H bond condensation

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Science China Chemistry 2024年第3期67卷 876-881页

作者： Yi Jing xinghua Wang Hui Han xin-Ran Liu xing-Chao Yu xi-Meng chen Donghui Wei Lai-Sheng Wang Xuenian chen College of Chemistry Green Catalysis CenterZhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy MaterialsHenan Normal UniversityXinxiang 453007China Department of Chemistry Brown UniversityProvidenceRI 02912USA

Polyhedral boranes are a class of well-known boron molecular clusters with unique physical and chemical properties,and great efforts have been made in the past decades to find more effective synthetic ***,the established synthetic methods suffer from low efficiency and low selectivity because the mechanism of the B-H bond condensation reaction,critical for the synthesis of the polyhedral boranes,is not well *** we report highly selective and efficient synthetic methods of the salts of the tetradecahydridoundecaborate(1-)(B_(11)H^(-)_(14)) and dodecahydrido-dodecaborates(2-)(B_(12)H_(12)^(2-)) anions by employing commercially available and inexpensive starting *** theoretical and experimental investigations are carried out to elucidate the reaction *** have found that the nature of the B-H bond condensation is the dihydrogen bonding interaction in which the positively charged hydrogens(bridged hydrogens) play a crucial *** current study has not only led to more effective and selective synthetic methods for B_(11)H^(-)_(14) and B_(12)H_(12)^(2-) but also unveiled the nature of the B-H bond condensation and the general formation mechanisms of polyhedral *** finding will facilitate the development of more effective synthetic methods for polyhedral boranes and spur their wide application.

关键词： Boranes polyhedral boranes dihydrogen bond nucleophilicity

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