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秸秆施用下减施氮肥稻田有机碳和氮磷的排放特征

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生态与农村环境学报 2024年第8期40卷 1102-1112页

作者：赵家阳于建光于孟康王宁郭智薛利红杨林章江苏大学环境与安全工程学院江苏镇江212001 江苏省农业科学院农业资源与环境研究所江苏南京210014 农业农村部长江下游平原农业环境重点实验室江苏南京210014

为了解秸秆施用下减施氮肥对稻田有机碳和氮磷排放特征的影响,进而为稻田投入品的优化施用以及田间养分管理提供技术支撑,通过盆钵试验研究小麦秸秆还田与肥料施用对高砂土和黄泥土2种土壤的田面水有机碳和氮磷浓度、潜在可排放量及水... 详细信息

为了解秸秆施用下减施氮肥对稻田有机碳和氮磷排放特征的影响,进而为稻田投入品的优化施用以及田间养分管理提供技术支撑,通过盆钵试验研究小麦秸秆还田与肥料施用对高砂土和黄泥土2种土壤的田面水有机碳和氮磷浓度、潜在可排放量及水稻产量的影响。结果表明,高砂土稻田的田面径流养分排放风险远大于黄泥土,其中基肥期更为明显;磷在基肥期田面径流中的排放风险最大,施加秸秆处理的有机碳在蘖肥期田面径流中的排放风险最大,而氮在穗肥期的排放风险最大;无论高砂土还是黄泥土,秸秆施用基础上,相比施用常量氮肥,施用减量氮肥在保证产量不受明显影响的同时,可以有效降低田面径流养分排放风险。在小麦秸秆还田条件下,施用减量氮肥与常量氮肥相比,高砂土稻田田面水的COD、DOC、TN和TP平均可排放量分别降低34.92%、15.47%、35.37%和53.93%,水稻产量降低12.01%,黄泥土稻田田面水的COD、TN和TP平均可排放量分别降低24.82%、23.75%、2.84%,而水稻产量提高3.99%。总之,秸秆还田时减施氮肥利于降低高砂土和黄泥土田面水COD、TN、NH_(4)^(+)-N和NO_(3)^(-)-N的潜在排放风险,以稳定水稻产量和防控稻田养分田面径流流失为目标,高砂土稻田在水稻种植时氮肥施用应减量多次,并避免小麦秸秆还田,而黄泥土稻田在氮肥施用时应混施秸秆。

关键词：稻田秸秆减施氮肥田面水有机碳氮磷

Quadrilateral plate fractures of the acetabulum:Classification,approach,implant therapy and related research progress

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World Journal of Clinical Cases 2022年第2期10卷 412-425页

作者： Xue-Feng Zhou Si-Chao Gu Wan-Bo Zhu jia-zhao yang Lei Xu Shi-Yuan Fang Department of Orthopedics The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230000Anhui ProvinceChina Graduate School Wannan Medical CollegeWuhu 241000Anhui ProvinceChina Department of Traumatic Orthopedics The First Affiliated Hospital of USTCHefei 230001Anhui ProvinceChina

The quadrilateral plate(QP)is an essential structure of the inner wall of the acetabulum,an important weight-bearing joint of the human body,which is often involved in acetabular *** operative exposure,reduction and fixation of QP fractures have always been the difficulties in orthopedics due to the special morphological structure and anatomical features of the ***,there have been many effective methods and instruments developed for QP exposure,reduction and fixation by virtue of the combined efforts of numerous *** the same time,each method presents with its own advantages and disadvantages,resulting in different *** is necessary to have a thorough understanding of the anatomy,radiology and fixation techniques of the QP in terms of patient prognosis *** this paper,the anatomical features,definition and classification of QP,operative approach selection,implant internal fixation methods and efficacy were reviewed.

关键词： Acetabular fracture Quadrilateral plate Fracture classification Operative approach Implant Internal fixation

A Comparative Study of the Power-law Relationship between the Pulse width and Energy of Precursor and Main Burst

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Research in Astronomy and Astrophysics 2024年第3期24卷 144-168页

作者： Hui-Ying Deng zhao-yang Peng jia-Ming Chen Dan Zhu College of Physics and Electronic Information Yunnan Normal UniversityKunming 650500China

In gamma-ray burst prompt emission,there is still no consistent conclusion if the precursor and main burst share the same *** this paper,we try to study this issue based on the relationship between pulse width and energy of the precursor and main *** systematically search the light curve data observed by Swift/BAT and Fermi/GBM,and find 13 long bursts with well-structured precursors and main *** fitting the precursor light curve of each different energy channel with the Norris function,we find that there is not only a power-law relationship between precursor width and energy,but also a power-law relationship between the ratio of the rising width to the decaying width and *** comparing the relationship between the precursors and the main burst pulses,we find that the distribution of the precursors and the relationship between the power-law indices are roughly the same as those of the main *** addition,it is found that the precursor width distribution as well as the upper limit of the pulse width ratio does not exceed 1 and both are asymmetric,which are also consistent with the main *** indicate that the precursor and the main burst are indistinguishable,and the precursor and the main burst may have the same physical origin.

关键词： methods data analysis-(stars) gamma-ray burst general-shock waves

Linearized waveform inversion for vertical transversely isotropic elastic media:Methodology and multi-parameter crosstalk analysis

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Petroleum Science 2024年第1期21卷 252-271页

作者： Ke Chen Lu Liu Li-Nan Xu Fei Hu Yuan yang jia-Hui Zuo Le-Le Zhang yang zhao National Key Laboratory of Petroleum Resources and Engineering Unconventional Petroleum Research InstituteChina University of Petroleum(Beijing)Beijing102249China Aramco Beijing Research Center Aramco AsiaBeijing100102China University of Lausanne LausanneCH-1015Switzerland Bureau of Geophysical Prospecting China National Petroleum CorporationZhuozhou 072750HebeiChina

Seismic migration and inversion are closely related techniques to portray subsurface images and identify hydrocarbon *** migration aims at obtaining structural images of subsurface geologic *** specifically,seismic migration estimates the reflectivity function(stacked average reflectivity or pre-stack angle-dependent reflectivity)from seismic reflection *** the other hand,seismic inversion quantitatively estimates the intrinsic rock properties of subsurface *** seismic inversion methods are applicable to detect hydrocarbon reservoirs that may exhibit lateral variations in the inverted *** there exist many differences,pre-stack seismic migration is similar with the first iteration of the general linearized seismic ***,seismic migration and inversion techniques assume an acoustic or isotropic elastic *** reservoirs such as shale and tight sand formation have notable anisotropic *** present a linearized waveform inversion(LWI)scheme for weakly anisotropic elastic media with vertical transversely isotropic(VTI)*** is based on two-way anisotropic elastic wave equation and simultaneously inverts for the localized perturbations(ΔVp_(0)/Vp_(0)/Vs_(0)/Vs_(0)/,Δ∈,Δδ)from the long-wavelength reference *** proposed VTI-elastic LWI is an iterative method that requires a forward and an adjoint operator acting on vectors in each *** derive the forward Born approximation operator by perturbation theory and adjoint operator via adjoint-state *** inversion has improved the quality of the images and reduces the multi-parameter crosstalk comparing with the adjoint-based *** have observed that the multi-parameter crosstalk problem is more prominent in the inversion images for Thomsen anisotropy ***,the Thomsen parameter is the most difficult to *** also analyze the multi-parameter crosstalk using scattering radiation patte

关键词： Elastic Anisotropy Least-squares imaging Waveform inversion Computational geophysics

Decoupling Algorithms for the Gravitational Wave Spacecraft

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 325-337页

作者： XueWang Weizhou Zhu zhao Cui Xingguang Qian Jinke yang jianjun jia Yikun Wang Key Laboratory of Space Active Opto-Electronics Technology Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai200083China University of Chinese Academy of Sciences Beijing100049China Key Laboratory of GravitationalWave Precision Measurement of Zhejiang Province Hangzhou Institute for Advanced StudyHangzhou310024China

The gravitational wave spacecraft is a complex multi-input multi-output dynamic *** gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precision *** one spacecraftwith two laser links,compared to one spacecraft with a single laser link,requires an upgraded decoupling algorithmfor the link *** decoupling algorithmwe designed reassigns the degrees of freedomand forces in the control loop to ensure sufficient degrees of freedomfor optical axis *** addressing the distinct dynamic characteristics of different degrees of freedom,a transfer function compensation method is used in the decoupling process to further minimize motion *** open-loop frequency response of the systemis obtained through *** upgraded decoupling algorithms effectively reduce the open-loop frequency response by 30 *** transfer function compensation method efficiently suppresses the coupling of low-frequency noise.

关键词： Gravitational waves spacecraft laser acquisition decoupling algorithms dynamical model optical axis control

Perenniality:From model plants to applications in agriculture

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Molecular Plant 2024年第1期17卷 141-157页

作者： Bo zhao jia-Wei Wang National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant Sciences(CEMPS)Institute of Plant Physiology and Ecology(SIPPE)Chinese Academy of Sciences(CAS)Shanghai 200032China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Key Laboratory of Plant Carbon Capture CASShanghai 200032China New Cornerstone Science Laboratory Shanghai 200032China

To compensate for their sessile nature,plants have evolved sophisticated mechanisms enabling them to adapt to ever-changing *** such prominent feature is the evolution of diverse life history strategies,particularly such that annuals reproduce once followed by seasonal death,while perennials live longer by cycling growth *** intrinsic phenology is primarily genetic and can be altered by environmental *** evolutionary transitions between annual and perennial life history strategies are common,perennials account for most species in nature because they survive well under year-round *** proportion,however,is reversed in ***,perennial crops promise to likewise protect and enhance the resilience of agricultural ecosystems in response to climate *** significant endeavors that have been made to generate perennial crops,progress is slow because of barriers in studying perennials,and many developed species await further *** findings in model species have illustrated that simply rewiring existing genetic networks can lead to lifestyle *** implies that engineering plant life history strategy can be achieved by manipulating only a few key *** this review,we summarize our current understanding of genetic basis of perenniality and discuss major questions and challenges that remain to be addressed.

关键词： perenniality developmental plasticity flowering time poplar Arabis alpina perennial crops life history strategy

Stacking MoS_(2) flower-like microspheres on pomelo peels-derived porous carbon nanosheets for high-efficient X-band electromagnetic wave absorption

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Nano Research 2024年第3期17卷 1607-1615页

作者： jia zhao Zhe Gu Qingguo Zhang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China

The key to solve increasingly severe electromagnetic(EM)pollution is to explore sustainable,easily prepared,and cost-effective EM wave absorption materials with exceptional absorption ***,instead of anchoring on carbon materials in single layer,MoS_(2) flower-like microspheres were stacked on the surface of pomelo peels-derived porous carbon nanosheets(C)to fabricate MoS_(2)@C nanocomposites by a facile solvothermal *** wave absorption performances of MoS_(2)@C nanocomposites in X-band were systematically investigated,indicating the minimum reflection loss(RLmin)of-62.3 dB(thickness of 2.88 mm)and effective absorption bandwidth(EAB)almost covering the whole X-band(thickness of 2.63 mm)with the filler loading of only 20 wt.%.Superior EM wave absorption performances of MoS_(2)@C nanocomposites could be attributed to the excellent impedance matching characteristic and dielectric loss capacity(conduction loss and polarization loss).This study revealed that the as-prepared MoS_(2)@C nanocomposites would be a novel prospective candidate for the sustainable EM absorbents with superior EM wave absorption performances.

关键词： pomelo peels-derived porous carbon nanosheets(C) MoS_(2)@C nanocomposites stacked structure electromagnetic(EM)wave absorption

CSST Dense Star Field Preparation: A Framework for Astrometry and Photometry for Dense Star Field Images Obtained by the China Space Station Telescope(CSST)

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Research in Astronomy and Astrophysics 2024年第7期24卷 161-172页

作者： Yining Wang Rui Sun Tianyuan Deng Chenghui zhao Peixuan zhao jiayi yang Peng jia Huigen Liu Jilin Zhou College of Electronic Information and Optical Engineering Taiyuan University of Technology School of Astronomy&Space Science Nanjing University Peng Cheng Lab

The China Space Station Telescope(CSST) is a telescope with 2 m diameter, obtaining images with high quality through wide-field observations. In its first observation cycle, to capture time-domain observation data, the CSST is proposed to observe the Galactic halo across different epochs. These data have significant potential for the study of properties of stars and exoplanets. However, the density of stars in the Galactic center is high, and it is a well-known challenge to perform astrometry and photometry in such a dense star field. This paper presents a deep learning-based framework designed to process dense star field images obtained by the CSST, which includes photometry, astrometry, and classifications of targets according to their light curve periods. With simulated CSST observation data, we demonstrate that this deep learning framework achieves photometry accuracy of 2% and astrometry accuracy of 0.03 pixel for stars with moderate brightness mag = 24(i band), surpassing results obtained by traditional methods. Additionally, the deep learning based light curve classification algorithm could pick up celestial targets whose magnitude variations are 1.7 times larger than magnitude variations brought by Poisson photon noise. We anticipate that our framework could be effectively used to process dense star field images obtained by the CSST.

关键词： astrometry methods: data analysis techniques: photometric

Prediction of the short-term efficacy of anti-VEGF therapy for neovascular age-related macular degeneration using optical coherence tomography angiography

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Eye and Vision 2024年第3期10卷 21-30页

作者： Huixun jia Bing Lu Zhi zhao yang Yu Fenghua Wang Minwen Zhou Xiaodong Sun Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong University School of Medicine100 Hai Ning RoadShanghai200080People’s Republic of China Shanghai Key Laboratory of Ocular Fundus Diseases ShanghaiChina National Clinical Research Center for Eye Diseases ShanghaiChina Shanghai Engineering Center for Visual Science and Photomedicine ShanghaiChina Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases ShanghaiChina Clinical Research Institute Shanghai Jiao Tong University School of MedicineShanghaiChina

Background To evaluate whether the specific choroidal neovascularization(CNV)characteristics measured using optical coherence tomography angiography(OCTA)can predict the 6-month prognosis of neovascular age-related macular degeneration(nAMD)after anti-vascular endothelial growth factor(anti-VEGF)*** Patients with type 1,type 2,or mixed-type neovascularization(NV)were prospectively *** underwent an initial loading phase of three consecutive monthly intravitreal injections of Conbercept(0.5 mg)and were switched to a pro re nata(PRN)treatment *** images were evaluated for eyes that underwent follow-up assessments for more than 6 *** lesions were manually segmented,and the CNV area,vessel area,greatest vascular caliber(GVC),and greatest linear dimension(GLD)were compared between responders and *** masked graders independently measured the above-mentioned parameters using OCTA,and consistency was assessed using the intraclass correlation coefficient(ICC)*** logistic regression analysis was performed to evaluate the effect of a 3-month change in the CNV area,GLD,and GVC on the 6-month response to anti-VEGF *** Among the 60 eyes of 60 patients with nAMD,39 were responders and 21 were *** proportion of CNV types was significantly different between responders and non-responders(P=0.009).Patients with type 2 or mixed NV seemed more likely to respond to the treatment(28.2%vs.0.0%,and 30.8%vs.23.8%,respectively).The change in GVC showed a significant difference between responders(−4.98±17.17μm)and non-responders(11.01±14.10μm)after three monthly intravitreal anti-VEGF *** logistic regression analysis showed that only the change in GVC remained significant after controlling for baseline GVC,injection number,and CNV type(adjusted OR=1.083;P=0.008).Conclusions Type 2 and mixed-type NV were significantly associated with a better response to anti-VEGF *** i

关键词： Age-related macular degeneration Choroidal neovascularization Optical coherence tomography angiography Anti-VEGF