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Design and parameter optimization of air-suction wheel type of seedmetering device with elastic pad for maize

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 116-127页

作者： Yuhuan sun Junhai Guo Linrong Shi College of Mechanical and Electrical Engineering Gansu Agricultural UniversityLanzhou 730070China College of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730070China

Due to the maize growing agronomy requires ground covered by mulch film in the arid zones of the China Northwest region,the seed-metering device must roll over,break the film,and then throw seeds into ***,the uneven ground can cause the seed-metering device to shake,reducing seed-metering *** improve the adaptability for different shapes of maize seeds,a air suction wheel type seed-metering device with elastic pad was developed for better seed extraction and bump ***,the advantages and influencing factors of the elastic pad were analyzed through four processes of metering ***,the velocity distributions of six diameters of the suction hole are compared to determine the range with ***,a one-factor experiment was conducted to analyze the pattern of the factors(the seed layer height,the critical vacuum,the rotational speed of the seed disk,and the suction hole diameter)influencing the metering seed ***,a five-level quadratic rotation orthogonal design was used to optimize the *** show that the optimal values are that the seed layer height is 40 mm,and the critical vacuum is 2.85 kPa,and the rotational speed of the seed disk is 20.1 r/*** validation experiment resulted in a 93.79%qualified index,with a 4.02%missing index and a 2.19%multiple index.

关键词： maize seeds seed-metering device with air suction elastic suction parameter optimization

Eat at the right time: Regulation of ER-phagy receptors in plant response to environmental stresses

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Molecular Plant 2024年第2期17卷 236-239页

作者： Yang Shao Jiaqi sun Huanquan Zheng The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266237China Department of Biology McGill UniversityMontrealQC H3A 1B1Canada

The endoplasmic reticulum(ER)is a cellular factory for biosynthesis of proteins and *** accommodate a wide array of biosynthetic demands in responses to environmental stresses,the plant ER remodels to maintain a structural and functional homeostasis.A key process facilitating this balance is selective autophagy of the ER(ER-phagy),where malfunctioned ER is recognized,engulfed by autophagosomes,and then delivered to the vacuole for degradation.

关键词： maintain accommodate function

Regional anesthesia in a patient with primary ciliary dyskinesia:A case report

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World Journal of Clinical Cases 2024年第17期12卷 3183-3187页

作者： Hyung Joon park Ye Hwan Kim young Joon Yoon Sang Yun Cho Department of Anesthesiology and Pain Medicine Hanyang University Guri HospitalGuri-si 471-701Gyeonggi-doSouth Korea

BACKGROUND Primary ciliary dyskinesia(PCD)is an inherited autosomal-recessive disorder of impaired mucociliary clearance characterized by chronic respiratory diseases,otolaryngological diseases,central nervous system abnormalities,reproductive system abnormalities,and cardiac function *** anesthesia in these patients is associated with a higher incidence of respiratory complications than in patients without the *** SUMMARY A 16-year-old male patient was referred to the emergency room complaining of right ankle pain due to distal tibiofibular *** years prior,he had been diagnosed with *** that time,he had experienced several episodes of pneumonia,sinusitis,and chronic middle ear infections,for which he underwent surgical *** the current admission,he presented with cough and sputum but no other respiratory symptoms.A chest computed tomography scan revealed centrilobular ground-glass opacities in both lower lobes and a calcified nodule in the left lower *** the surgical procedure and postoperative pain management,combined spinal-epidural anesthesia was *** patient’s postoperative pain score was measured by the numerical rating scale(NRS).On the day of surgery,his NRS was 5 *** the second postoperative day,the NRS score had decreased to 2–3 *** epidural catheter was removed on the fourth day following the *** patient was subsequently discharged no respiratory *** We performed combined spinal-epidural anesthesia in a patient with *** patient experienced no additional respiratory complications and was discharged with a low NRS score for pain.

关键词： Primary ciliary dyskinesia Combined spinal-epidural anesthesia Patient controlled epidural analgesia Lower limb operation Case report

Acetylacetone-TiO_(2) Promoted Large Area Compatible Cascade Electron Transport Bilayer for Efficient Perovskite Solar Cells

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Energy & Environmental Materials 2024年第2期7卷 221-228页

作者： Hyong Joon Lee Jin Kyoung park Jin Hyuck Heo Sang Hyuk Im Department of Chemical and Biological Engineering Korea University145 Anam-ro Seongbuk-guSeoul 17104Korea

In designing efficient perovskite solar cells(PSCs),the selection of suitable electron transport layers(ETLs)is critical to the final device performance as they determine the driving force for selective charge ***_(2)nanoparticles(NPs)based ETLs have been a popular choice for PSCs due to superior electron mobility,but their relatively deep-lying conduction band energy levels(ECB)result in substantial potential ***,TiO_(2)NPs establish favorable band alignment owing to shallower ECB,but their low intrinsic mobility and abundant surface trap sites impede the final *** this reason,constructing a cascaded bilayer ETL is highly desirable for efficient PSCs,as it can rearrange energy levels and exploit on advantages of an individual *** this study,we prepare SnO_(2)NPs and acetylacetone-modified TiO_(2)(Acac-TiO_(2))NPs and implement them as bilayer SnO_(2)/Acac-TiO_(2)(BST)ETL,to assemble cascaded energy band ***_(2)contributes to rapid charge carrier transport from high electron mobility while Acac-TiO_(2)minimizes band-offset and effectively suppresses interfacial ***,the optimized BST ETL generates synergistic influence and delivers power conversion efficiency(PCE)as high as 23.14%with open-circuit voltage(V_(oc))reaching 1.14 ***,the BST ETL is transferred to a large scale and the corresponding mini module demonstrates peak performance of 18.39%PCE from 25 cm^(2)aperture ***,the BST-based mini module exhibit excellent stability,maintaining 83.1%of its initial efficiency after 1000 h under simultaneous 1 sun light-soaking and damp heat(85℃/RH 85%)environment.

关键词： acetylacetone large area perovskite solar cells TiO_(2)

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Higher-order properties and extensions for indirect MRAC and APPC of linear systems

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Science China(Information Sciences) 2024年第4期67卷 218-238页

作者： Yanjun ZHANG Zhipeng ZHANG Jian sun Lei WANG Kangkang ZHANG National Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center College of Control Science and Engineering Zhejiang University Department of Electrical and Electronic Engineering Imperial College London KIOS Research and Innovation Center of Excellence University of Cyprus

Recently, a reference derived some new higher-order output tracking properties for direct model reference adaptive control(MRAC) of linear time-invariant(LTI) systems: limt→∞ e~((i))(t) = 0, i = 1,..., n~*-1, where n~* and e~((i))(t) denote the relative degree of the system and the i-th derivative of the output tracking error, respectively. However, a naturally arising question involves whether indirect adaptive control(including indirect MRAC and indirect adaptive pole placement control) of LTI systems still has higher-order tracking properties. Such properties have not been reported in the literature. Therefore, this paper provides an affirmative answer to this question. Such higher-order tracking properties are new discoveries since they hold without any additional design conditions and, in particular, without the persistent excitation condition. Given the higher-order properties, a new adaptive control system is developed with stronger tracking features.(1) It can track a reference signal with any order derivatives being unknown.(2) It has higher-order exponential or practical output tracking properties.(3) Finally, it is different from the usual MRAC system, whose reference signal’s derivatives up to the n~* order are assumed to be known. Finally, two simulation examples are provided to verify the theoretical results obtained in this paper.

关键词： higher-order tracking indirect adaptive control model reference adaptive control adaptive pole placement control

Electrocatalytic Reduction of CO_(2)to CO with Almost 100%Faradaic Efficiency Using Oxygen-Vacancy Enriched Two-Dimensional MgO

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CCS Chemistry 2024年第6期6卷 1477-1486页

作者： Yu Han sunggi An Xinyu Zhan Leiduan Hao Liang Xu Song Hong Dongmin park Yuxin Chen Yiwen Xu Jiwen Zhao Xinyi Tan Alex W.Robertson Yousung Jung Zhenyu sun State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029 Department of Chemical and Biomolecular Engineering(BK21four) Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141 Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081 Department of Physics University of WarwickCoventry

The design and development of cheap,abundant,and efficient electrocatalysts for selective CO_(2)electroreduction is highly desirable yet remains an ongoing ***,we report on our discovery of the use of two-dimensional MgO rich in oxygen vacancies(VO)as an electrocatalyst for the efficient reduction of CO_(2)to yield CO in 1-butyl-3-methylimidazolium hexafluorophosphate dissolved in *** faradaic efficiency toward CO reaches as high as 99.6±0.24%with a current density of up to 40.8 mA cm−*** functional theory calculations illustrate that the introduction of VO in MgO substantially lowers the reaction-free energy for the transformation of ^(*)COO^(−) to ^(*)COOH,the potential determining step,which greatly boosts CO_(2)conversion *** work opens the way to realizing economic and efficient CO_(2)electrolysis of group II metals.

关键词： CO_(2)reduction electrocatalysis CO MgO ionic liquid oxygen-vacancy

Degeneration of foundation cushion species induced by ecological constraints can cause massive changes in alpine plant communities

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Science China(Life Sciences) 2024年第4期67卷 789-802页

作者： Jianguo Chen Xufang Chen Lishen Qian Yazhou Zhang Bo Li Honghua Shi Lu sun Christian Schöb Hang sun Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China College of Resources and Environment Yunnan Agricultural UniversityKunming 650500China Área de Biodiversidad y Conservación Universidad Rey Juan CarlosMóstoles 28933Spain

Foundational cushion plants can re-organize community structures and sustain a prominent proportion of alpine biodiversity,but they are sensitive to climate *** loss of cushion species can have broad consequences for associated *** potential plant community changes with the population dynamics of cushion plants remain,however,*** eight plant communities along a climatic and community successional gradient,we assessed cushion population dynamics,the underlying ecological constraints and hence associated plant community changes in alpine communities dominated by the foundational cushion plant Arenaria *** population dynamics of Arenaria are attributed to ecological constraints at a series of life history *** functions are constrained by increasing associated beneficiary plants;subsequent seedling establishment is constrained by temperature,water and light availability,extreme climate events,and interspecific competition;strong competitive exclusion may accelerate mortality and degeneration of cushion *** with cushion dynamics,species composition,abundance and community structure gradually *** cushion plants completely degenerate,previously cushion-dominated communities shift to relatively stable communities that are overwhelmingly dominated by *** warming may accelerate the degeneration process of *** of this foundational cushion plant will possibly induce massive changes in alpine plant communities and hence ecosystem functions in alpine *** assessment of the population dynamics of foundation species is critical for an effective conservation of alpine biodiversity.

关键词： alpine ecosystem biodiversity change climate change plant community dynamics foundation species global warming population dynamics

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Pd(I)-catalyzed ring-opening arylation of cyclopropyl-α-aminoamides:Access toα-ketoamide peptidomimetics

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Chinese Chemical Letters 2024年第6期35卷 320-326页

作者： Yue sun Liming Yang Yaohang Cheng Guanghui An Guangming Li School of Chemistry and Materials Science Heilongjiang UniversityHarbin 150080China

We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-*** protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product *** selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal *** investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.

关键词： Pd(I)catalysis Ring-opening arylation Domino reactions Oligopeptides Late-stage functionalization

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Zircon U-Pb ages and O-Hf isotopes of Quaternary trachytes from the East Sea:Implications for the genesis of low-δ^(18)O magmas

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Geoscience Frontiers 2024年第2期15卷 41-54页

作者： Hyun-Ok Choi Jihye Oh Chang Hwan Kim Soon young Choi Won Hyuck Kim Chan Hong park Dokdo Research Center East Sea Research InstituteKorea Institute of Ocean Science and TechnologyUljin 36315Republic of Korea Deep-Sea and Seabed Mineral Resources Research Center Korea Institute of Ocean Science and TechnologyBusan 49111Republic of Korea Division of Science Education Kangwon National University1 Gangwondaehak-gilChuncheon-siGangwon-do 24341Republic of Korea

Quaternary intraplate magmatism formed several volcanic islands and seamounts,including Dokdo(DD),Ulleungdo(UD),Simheungtack(ST),Anyongbok,and Isabu in the southwest of the East Sea back-arc *** this study,we present whole-rock geochemical,zircon U–Pb age,and in situ O–Hf isotope data for the submerged volcanic rocks from DD,UD,and ST to provide new insights into the eruption timing of these volcanoes and constrain the magma evolution *** samples used in this study were trachytes and exhibited ferroan,alkalic,and metaluminous to weakly peraluminous *** showed light rare earth element(REE)-enriched patterns with(La/Yb)N ratios of 25.3–31.7 and mostly negative Eu anomalies in a chondrite-normalized REE *** addition,they were enriched in large-ion lithophile elements and high field strength elements;they exhibited positive Pb anomalies and strongly negative Ba,Sr,P,and Ti *** zircons yielded a weighted-mean 206Pb/238U age of 2.61,0.348–0.704,and 2.76–2.94 Ma for the DD,UD,and ST trachytes,*** zircons exhibited lowerδ^(18)O values than normal depleted mantle values,regardless of the crystallization age and spatial distribution of ***δ^(18)O values showed no correlation with U contents or Th/U ratios,indicating that the lowδ^(18)O signatures were of primary magmatic *** Hf isotopic compositions of the zircons were relatively heterogeneous but predominately characterized by positive eHf *** O–Hf mixing modeling revealed that low-δ^(18)O rocks with positive eHf values from the UD and ST volcanoes were derived from a hybrid source of recycled juvenile crustal materials with low-δ^(18)O and positive eHf signatures and an enriched mantle source with normalδ^(18)O and negative eHf *** juvenile oceanic crust in the source was likely metasomatized by seawater at high temperatures prior to *** contrast,the felsic magma that formed the DD volcanoes may have assimilated with regional

关键词： Quaternary intraplate volcanism East Sea Zircon O-Hf isotopes Low-δ^(18)O magma Recycled juvenile oceanic crust