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Fractionation of soil organic carbon in a calcareous soil after longterm tillage and straw residue management

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Journal of Integrative Agriculture 2022年第12期21卷 3611-3625页

作者： LI Teng-teng zhang Jiang-zhou zhang Hong-yan Peter CHRISITE zhang jun-ling Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems&CAS Engineering Laboratory for Vegetation Ecosystem Restoration on Islands and Coastal Zones South China Botanical GardenChinese Academy of Sciences(CAS)Guangzhou 510650P.R.China College of Resources and Environmental Sciences China Agricultural University/National Academy of Agriculture Green Development/Key Laboratory of Plant–Soil InteractionsMinistry of EducationBeijing 100193P.R.China College of Resources and Environment/International Magnesium Institute Fujian Agriculture and Forestry UniversityFuzhou 350002P.R.China

No-tillage(NT)and straw return(S)collectively affect soil organic carbon(SOC).However,changes in the organic carbon pool have been ***,we assessed the quantity and quality of SOC after 11 years of tillage and straw return on the North China *** of SOC and its labile fractions(particulate organic carbon(POC),potassium permanganate-oxidizable organic carbon(POXC),microbial biomass carbon(MBC),and dissolved organic carbon(DOC)),components of DOC by fluorescence spectroscopy combined with parallel factor analysis(PARAFAC),and the chemical composition of SOC by 13C NMR(nuclear magnetic resonance)spectroscopy were *** comprised conventional tillage(CT)and NT under straw removal(S0),return of wheat straw only(S1),or return of both wheat straw and maize residue(S2).Straw return significantly increased the concentrations and stocks of SOC at 0–20 cm depth,but NT stratified them with enrichment at 0–10 cm and a decrease at 10–20 cm compared to CT,especially under *** C fractions showed similar patterns of variation to that of SOC,with POC and POXC more sensitive to straw return and the former more sensitive to *** fluorescence components of DOC were identified,mainly comprising humic-like substances with smaller amounts of fulvic acid-like substances and *** return significantly decreased the fluorescence index(FI)and autochthonous index(BIX)and increased the humification index(HIX).No-tillage generally increased HIX in topsoil but decreased it and increased the FI and BIX below the *** abudance order of the chemical composition of SOC was:O-alkyl C>alkylC>aromatic-C>***,NT under S2 effectively increased SOC and its labile C forms and DOC humification in topsoil and microbially-derived DOC below the *** of both wheat and maize straw was a decisive factor in promoting SOC in the plow *** stratification of SOC under NT may confer a long-term influence on

关键词： soil organic carbon labile C fractions EEM fluorescence PARAFAC analysis 13C NMR spectrometry

AMF和PGPR单独或“跨界”互作促进植物耐盐性的研究进展

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植物营养与肥料学报 2024年第7期30卷 1354-1366页

作者：秦敬泽秦泽峰倪刚谢沐希周大朴王光州张俊伶中国农业大学资源与环境学院/国家农业绿色发展研究院/养分资源高效利用全国重点实验室北京100193

盐碱地改良和利用对拓展我国后备耕地资源及保障国家粮食安全具有重要意义。根际微生物作为植物的“第二基因组”,在提高作物抗盐碱胁迫能力,促进作物“以种适地”方面具有巨大潜力。其中,丛枝菌根真菌(arbuscular mycorrhizal fungi,A... 详细信息

盐碱地改良和利用对拓展我国后备耕地资源及保障国家粮食安全具有重要意义。根际微生物作为植物的“第二基因组”,在提高作物抗盐碱胁迫能力,促进作物“以种适地”方面具有巨大潜力。其中,丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)和植物根际促生细菌(plant growth promoting rhizobacteria,PGPR)均为重要的根际有益微生物,能显著提高植物耐盐性。本文分别总结了AMF和PGPR提高植物抗盐能力的相关研究进展,并进一步梳理了两者协同提高植物耐盐的机制,包括提高养分效率、调节激素内稳态、提高植物诱导抗性以及调控转录因子表达等,最后提出了基于两者跨界组合的改良方向。旨在充分理解盐胁迫条件下微生物耐盐促生的作用机制,为充分挖掘微生物资源潜力和发展生物技术治理盐碱地提供重要的科学支撑。

关键词：盐化土壤丛枝菌根真菌植物根际促生细菌植物耐盐性

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Light(Science & Applications) 2024年第2期13卷 333-346页

作者： Yifan Sun Qian Li ling-jun Kong Xiangdong zhang Key Laboratory of advanced optoelectronic quantum architecture and measurements of Ministry of Education Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology100081BeijingChina

Compared with electrical neural networks,optical neural networks(ONNs)have the potentials to break the limit of the bandwidth and reduce the consumption of energy,and therefore draw much attention in recent *** far,several types of ONNs have been ***,the current ONNs cannot realize the acceleration as powerful as that indicated by the models like quantum neural *** to construct and realize an ONN with the quantum speedup is a huge ***,we propose theoretically and demonstrate experimentally a new type of optical convolutional neural network by introducing the optical *** is called the correlated optical convolutional neural network(COCNN).We show that the COCNN can exhibit“quantum speedup”in the training *** character is verified from the two *** is the direct illustration of the faster convergence by comparing the loss function curves of the COCNN with that of the traditional convolutional neural network(CNN).Such a result is compatible with the training performance of the recently proposed quantum convolutional neural network(QCNN).The other is the demonstration of the COCNN’s capability to perform the QCNN phase recognition circuit,validating the connection between the COCNN and the ***,we take the COCNN analog to the 3-qubit QCNN phase recognition circuit as an example and perform an experiment to show the soundness and the feasibility of *** results perfectly match the theoretical *** proposal opens up a new avenue for realizing the ONNs with the quantum speedup,which will benefit the information processing in the era of big data.

关键词： process quantum convolution

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抗菌牙科粘接剂在龋病治疗中的研究进展

牙体牙髓牙周病学杂志 2024年第6期29卷 350-355页

作者：张灵俊章可可孙妍汪敏郑高哲潘乙怀余杰温州医科大学口腔医学院·附属口腔医院浙江温州325000

牙科粘接剂在治疗细菌相关性疾病-龋齿过程中,发挥连接复合树脂及牙体组织的作用。通过对粘接剂进行改性,使其具备一定的抗菌功能,可有效抑制粘接界面细菌生长。本综述系统评估和总结了改性牙科粘接剂的各种策略,重点探讨包括金属及其... 详细信息

牙科粘接剂在治疗细菌相关性疾病-龋齿过程中,发挥连接复合树脂及牙体组织的作用。通过对粘接剂进行改性,使其具备一定的抗菌功能,可有效抑制粘接界面细菌生长。本综述系统评估和总结了改性牙科粘接剂的各种策略,重点探讨包括金属及其化合物、季铵盐、天然抗菌药物、抗菌肽及载药系统等抗菌成分的应用前景。

关键词：牙科粘接剂龋病抗菌金属季铵盐抗菌肽载药

Multiwavelength Observations of the Infrared Dust Bubble N75 and its Surroundings

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Research in Astronomy and Astrophysics 2024年第4期24卷 262-270页

作者： Quan-ling Cui Chuan-Peng zhang jun-Jie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar *** this work,we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C^(18)O,HCO^(+),HNC and N_(2)H^(+)observed by the 30 m IRAM *** also study the targets using data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,NRAO VLA Sky Survey and Bolocam Galactic Plane *** found that the C^(18)O emission is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to *** ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission,which may be excited by radiation from *** found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II with several class I cases distributed around N75,but no class II *** also found evidence of expanding feedback,which could have triggered star formation.

关键词： ISM:bubbles infrared:ISM galaxies:star formation

Possible Habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in the Initial Conditions of High-mass Star Formation

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted from the gas phase by freezing out onto dust ***,the N-bearing and deuterated species could remain gaseous under these extreme conditions,suggesting that they may serve as ideal *** this paper,using the Plateau de Bure Interferometer and Very Large Array observations at 1.3 mm,3.5 mm,and 1.3 cm,we investigate the possible habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in eight massive precluster and protocluster clumps G18.17,G18.21,G23.97N,G23.98,G23.44,G23.97S,G25.38,and *** found that the NH3cores are in good agreement with the 3.5 mm peak emission,but the NH_(3)is much more extended than the 3.5 mm emission *** SO distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any SO emission in the four earliest star formation sources.C^(18)O is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the NH_(2)D cores are mainly located in the temperature range of 13.0-20.0 K,and the NH_(2)D lines may be strongly depleted above 20 K.

关键词： galaxies:star formation techniques:interferometric methods:observational

Investigation on the syntheses and structures of Y^(Ⅲ) complexes with ami-nopolycarboxylic acids (Ⅳ)

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Rare Metals 2002年第2期21卷 106-112页

作者： WANG jun, zhang Xiangdong, ling Xiao, JIA Weiguo, and FAN DaminDepartment of Chemistry, Liaoning University, Shenyang, 110036, China Department of Chemistry Liaoning University Shenyang 110036

This paper deals with the structure of the Y^iii complex withaminopolycarboxylic acids, synthesis and struc- tural determinationof the complex (NH_4)[Y^III(edta)(H_2O)_3] ·3 H_2O (edta =ethylenediaminetetraacetic acid). The crystal and molecularstructures of the (NH_4)[Y^III(edta)(H_2O)_3] ·3 H_2O complex havebeen determined by single-crystal X-ray structure analysis. Thecrystal of the complex (NH_4)[Y^III(edta)(H_2O)_3] ·3 H_2O belongsto orthorhombic crystal system and fdd2 space group.

关键词： Y^III aminopolycarboxylic acids Complex structure

Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:Materials International 2024年第02期34卷 376-388页

作者： ling zhang Yinglong Li School of Materials Science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy Mechanical performance Mg-Gd-Y-Zr alloy Texture development

An Efficient Optimization Design Framework for Low-Resistance Shape of Bionic Amphibious Robot

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China Ocean Engineering 2024年第1期38卷 117-128页

作者： zhang Dai-yu zhang Man-yu WANG Zhi-dong ZHENG Wen-sheng ling Hong-jie HU jun-ming School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

To realize the low-resistance shape optimization design of amphibious robots,an efficient optimization design framework is proposed to improve the geometric deformation flexibility and optimization *** the proposed framework,the free-form deformation parametric model of the flat slender body is established and an analytical calculation method for the height constraints is *** method is introduced to carry out the high-precision resistance calculation and a constrained Kriging-based optimization method is built to improve the optimization efficiency by circularly infilling the new sample points which satisfying the ***,the shape of an amphibious robot example is optimized to get the low-resistance shape and the results demonstrate that the presented optimization design framework has the advantages of simplicity,flexibility and high efficiency.

关键词： amphibious robot optimization method free-form deformation CFD-based hydrodynamic calculation