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Analysis of sudden variations in photospheric magnetic fields during a large flare and their influences in the solar atmosphere

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Research in Astronomy and Astrophysics 2016年第8期16卷 95-112页

作者： Brajesh Kumar Ankala Raja Bayanna Parameswaran Venkatakrishnan shibu kuchandy mathew Udaipur Solar Observatory Physical Research Laboratory Dewali Badi Road Udaipur 313004 Rajasthan India Indian Institute of Astrophysics Ⅱ Block Koramangala Bangalore 560034 India

The solar active region NOAA 11719 produced a large two-ribbon flare on 2013 April 11. We have investigated sudden variations in the photospheric magnetic fields in this active region during the flare by employing magnetograms obtained in the spectral line Fe I 6173 A acquired by the Helioseismic and Magnetic Imager （HMI） onboard the Solar Dynamics Observatory （SDO） spacecraft. The analysis of the line-of-sight magnetograms from HMI show sudden and persistent magnetic field changes at different locations of the active region before the onset of the flare and during the flare. The vector magnetic field observations available from HMI also show coincident variations in the total magnetic field strength and its inclination angle at these locations. Using the simultaneous Dopplergrams obtained from HMI, we observe perturbations in the photospheric Doppler signals following the sudden changes in the magnetic fields in the aforementioned locations. The power spectrum analysis of these velocity signals shows enhanced acoustic power in these affected locations during the flare as compared to the pre-flare condition. Accompanying these observations, we have also used nearly simultaneous chromospheric observations obtained in the spectral line Ha 6562.8 A by the Global Oscillation Network Group （GONG） to study the evolution of flare- ribbons and intensity oscillations in this active region. The Ha intensity oscillations also show enhanced oscillatory power during the flare in the aforementioned locations. These results indicate that the transient Lorentz force associated with sudden changes in the magnetic fields could drive localized photospheric and chromospheric oscillations, like the flare-induced oscillations in the solar atmosphere.

关键词： Sun sunspots -- Sun flares -- Sun magnetic fields -- Sun oscillations -- Sun photosphere-- Sun chromosphere

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Spatio-temporal variation and relationship between agricultural efficiency and irrigation intensity in a semi-arid region of India

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Regional Sustainability 2024年第2期5卷 123-139页

作者： shibu DAS Kaushal Kumar SHARMA Suranjan MAJUMDER Debabrata DAS Indrajit Roy CHOWDHURY Centre for the Study of Regional Development School of Social SciencesJawaharlal Nehru UniversityNew Delhi110067India Department of Geography&Applied Geography University of North BengalDarjeeling734013India Geography Department of Krishnagar Government College Krishnagar741101India

A surging population in Karnataka State,a semi-arid region in India,poses a threat to both food security and livelihood sustainability,necessitating a concentrated effort to bolster agricultural efficiency and achieve United Naton’s Sustainable Development Goal 2(zero hunger).Therefore,in order to address the pressing issue of food scarcity in Karnataka,this study meticulously examined the spatio-temporal variation of agricultural efficiency and irrigation intensity in Karnataka,uncovering its significant dependence of agricultural efficiency on irrigation ***,this study used a one-way analysis of variance(ANOVA)to ascertain significant differences in the means of agricultural efficiency and irrigation intensity during 2004-2005 and *** study showed that the maximum improvement in agricultural efficiency index was recorded in Belgaum(40.24),Gulbarga(24.77),and Yadgir districts(22.92)between 2004-2005 and 2018-2019,which indicated the progressing trend and better scope for agriculture *** the contrary,some districts expressed threat(a decline of above 20.00 of agricultural efficiency index)and needed special care for the improvement of agricultural efficiency in four northern districts(Bagalkot,Bidar,Raichur,and Bijapur),three southern districts(Chitradurga,Chikballapur and Hassan),and two southern districts(Koppal and Gadag)in *** 2004-2005,irrigation intensity varied from 3.19%to 56.39%,with the lowest irrigation intensity in Kodagu District and the highest irrigation intensity in Shimoga *** 2018-2019,irrigation intensity changed from 0.77%to 72.77%,with the lowest irrigation intensity in Kodagu District and the highest in Dakshin Kannad ***,the research scrutinized the complex relationship between agricultural efficiency and irrigation intensity,with the correlation coefficient increased from 0.162 during 2004-2005 to 0.255 during *** implies that in both periods,a low positive

关键词： Agricultural efficiency Irrigation intensity One-way analysis of variance(ANOVA) Food security Karnataka

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生态翻译学视域下的宋词英译研究--以《醉花阴》许渊冲译本为例

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盐城工学院学报（社会科学版） 2024年第2期37卷 70-73页

作者：牛艳争陈士部淮北师范大学外国语学院安徽淮北235000

中国古诗词英译是助推中国文化走出去的重要途径之一。通过李清照《醉花阴·薄雾浓云愁永昼》许渊冲英译本对原词的所言之情和审美要求的再现,验证胡庚申生态翻译学理论对宋词翻译的指导意义,以期为更多的宋词英译提供些许借鉴和启示。

关键词：生态翻译学宋词英译三维转换

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超高温陶瓷改性C/C复合材料抗氧化烧蚀性能研究进展

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材料导报 2024年第S1期38卷 104-114页

作者：孙丹羽朱世步刘泰山张强马荣檄西安航天复合材料研究所西安710025 陕西省航天复合材料重点实验室西安710025

碳/碳(C/C)复合材料具有高强、轻质和耐温等优势,在航天领域取得广泛应用;但由于其抗氧化性能较差,难以满足高超声速飞行器长时飞行、大气层再入飞行和跨大气层飞行的服役环境。利用超高温陶瓷改性C/C复合材料(C/C-UHTC)可以显著提高C/... 详细信息

碳/碳(C/C)复合材料具有高强、轻质和耐温等优势,在航天领域取得广泛应用;但由于其抗氧化性能较差,难以满足高超声速飞行器长时飞行、大气层再入飞行和跨大气层飞行的服役环境。利用超高温陶瓷改性C/C复合材料(C/C-UHTC)可以显著提高C/C复合材料的抗氧化烧蚀性能,有望满足新一代飞行器长时间抗氧化、抗烧蚀及结构强度的要求。本文总结了C/C-UHTC复合材料烧蚀性能的常用测试方法,包括氧-乙炔烧蚀、等离子烧蚀、激光烧蚀和风洞烧蚀,简要介绍了各种烧蚀性能测试方法的特点。此外,对近年来Zr系和Hf系单组元、双组元和三组元C/C-UHTC复合材料的烧蚀性能及烧蚀机理进行详细阐述。

关键词：超高温陶瓷 C/C复合材料抗氧化烧蚀性能测试方法烧蚀机制

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On the line profile changes observed during the X2.2 class flare in the active region NOAA 11158

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Research in Astronomy and Astrophysics 2014年第2期14卷 207-220页

作者： Ankala Raja Bayanna Brajesh Kumar Parameswaran Venkatakrishnan shibu Kunchandy mathew Belur Ravindra Savita Mathur Rafael A Garcia Udaipur Solar Observatory Physical Research LaboratoryDewaliBadi RoadUdaipur 313 004India Indian Institute of Astrophysics II BlockKoramanglaBangalore 560034India Space Science Institute 4750 Walnut Street Suite#205BoulderCO 80301USA Laboratoire AIM CEA/DSM-CNRSUniversit'e Paris 7 DiderotIRFU/SApCentre de Saclay91191Gif-sur-YvetteFrance

The solar active region NOAA 11158 produced a series of flares during its passage through the solar disk. The first major flare （of class X2.2） of the current solar cycle occurred in this active region on 2011 February 15 around 01：50 UT. We have analyzed the Dopplergrams and magnetograms obtained by the Helioseismic and Magnetic Imager （HMI） instrument onboard Solar Dynamics Observatory to examine the photospheric velocity and magnetic field changes associated with this flare. The HMI instrument provides high-quality Doppler and magnetic maps of the solar disk with 0.5＂ spatial scale at a cadence of 45 s along with imaging spectroscopy. We have identified five locations of velocity transients in the active region during the flare. These transient velocity signals are located in and around the flare ribbons as observed by Hinode in the Ca II H wavelength and the footpoints of hard X-ray enhancement are in the energy range 12-25 keV from RHESSI. The changes in shape and width of two circular polarization states have been observed at the time of transients in three out of five locations. Forward modeling of the line profiles shows that the change in atmospheric parameters such as magnetic field strength, Doppler velocity and source function could explain the observed changes in the line profiles with respect to the pre-flare condition.

关键词： Sun: activity -- Sun: sunspot -- Sun: flares -- Sun: spectroscopy --Sun: velocity and magnetic fields

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A study of the relation between intensity oscillations and magnetic field parameters in a sunspot: Hinode observations

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Research in Astronomy and Astrophysics 2014年第11期14卷 1458-1468页

作者： A.Raja Bayanna shibu K.mathew Brajesh Kumar Rohan E.Louis P.Venkatakrishnan Udaipur Solar Observatory Physical Research Laboratory Leibniz-Institut für Astrophysik Potsdam (AIP) An der Sternwarte 16 14482 PotsdamGermany

We present properties of intensity oscillations of a sunspot in the photo- sphere and chromosphere using G band and Ca u H filtergrams from Hinode. Intensity power maps as function of magnetic field strength and frequency reveal reduction of power in the G band with an increase in photospheric magnetic field strength at all frequencies. In Ca II H, however, stronger fields exhibit more power at high frequen- cies, particularly in the 4.5-8.0 mHz band. Power distributions in different locations of the active region show that the oscillations in Ca II H exhibit more power compared to that of the G band. We also relate the power in intensity oscillations with differ- ent components of the photospheric vector magnetic field using near simultaneous spectro-polarimetric observations of the sunspot from the Hinode spectropolarime- ter. The photospheric umbral power is strongly anti-correlated with the magnetic field strength and its line-of-sight component but there is a good correlation with the trans- verse component. A reversal of this trend is observed in the chromosphere except at low frequencies （V≤ 1.5 mHz）. The power in sunspot penumbrae is anti-correlated with the magnetic field parameters at all frequencies （1.0 ≤ v ≤ 8.0 mHz） in both the photosphere and chromosphere, except that the chromospheric power shows a strong correlation in the frequency range 3-3.5 mHz.

关键词： Sun photosphere -- Sun chromosphere -- Sun oscillations -- Sun magnetic fields -- Sun Hinode

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血清胸腺因子的大鼠围产期毒性试验研究

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癌变．畸变．突变 2024年第2期36卷 138-142页

作者：杨玉李荣光王丹黄雅理单纯刘师卜林飞佳木斯大学基础医学院黑龙江佳木斯154007 中国食品药品检定研究院北京100050 佳木斯大学附属第二医院黑龙江佳木斯154007 佳木斯大学临床医学院黑龙江佳木斯154007 海关总署国际检验检疫标准与技术法规研究中心北京100013

目的:观察血清胸腺因子对大鼠妊娠晚期、分娩期、哺乳期及胚胎和胎仔出生后生长发育、学习能力以及生殖能力的影响。方法:选择交配后的雌性SD大鼠,每组20只,从妊娠第15天至哺乳期结束,分别按0.88、1.75和3.50 mg/kg连续皮下注射给予血... 详细信息

目的:观察血清胸腺因子对大鼠妊娠晚期、分娩期、哺乳期及胚胎和胎仔出生后生长发育、学习能力以及生殖能力的影响。方法:选择交配后的雌性SD大鼠,每组20只,从妊娠第15天至哺乳期结束,分别按0.88、1.75和3.50 mg/kg连续皮下注射给予血清胸腺因子,同时设0.9%氯化钠注射液为溶剂对照组,定期称取F0代雌鼠体质量、摄食量;F1代仔鼠确定出生存活率、哺乳期存活率,生理发育、新生反射达标天龄,训练学习、记忆能力,观察出生第12周后的仔鼠交配后的生殖行为,测定胚胎毒性各项指标。结果:注射血清胸腺因子后,溶剂对照组和受试药物各剂量组F0代妊娠鼠和哺乳鼠各周的平均体质量增长和摄食量正常,仔鼠总量、性别比和出生存活率(96.3%~97.9%)和哺乳期存活率(97.7%~98.9%)基本一致;F1代仔鼠的哺乳期和离乳后仔鼠平均体质量增长和摄食量基本正常。溶剂对照组仔鼠的生理发育和新生反射时间点检查项目均为正常达标天龄,游泳适应时间(28.5±15.8)s,空间定位建立时间(134.9±44.1)s,暗室电击反射建立时间(4.9±3.1)s,建立记忆电击次数1.7±0.9;F1代性成熟大鼠溶剂对照组的同笼交配率100%,妊娠率90%,平均着床数10.6±2.1,平均活胎数10.2±1.9,死胎数3,畸形胎数1;以上指标受试药物各剂量组间未见明显变化,与溶剂对照组比较,差异均无统计学意义(P>0.05)。结论:在本实验条件下,溶剂对照组与血清胸腺因子3个剂量组的大鼠妊娠后期个体及F1代胚胎及胎仔出生后生长发育、神经行为以及生殖能力等均未发现明显异常,未见围产期毒性反应。

关键词：血清胸腺因子大鼠仔鼠生长发育生殖毒性

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基于网络药理学探讨葛根治疗肝损伤的作用机制

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癌变．畸变．突变 2024年第2期36卷 118-123页

作者：刘师卜郑济凡张励马利波朵慧刘梦琪中国食品药品检定研究院北京100050

目的:探究葛根治疗肝损伤的有效成分、靶标和作用通路,为葛根用于肝损伤的治疗提供理论依据。方法:基于中医药整合药理学网络计算平台(TCMIP)、中药综合资源数据库(TCMID)、中药系统药理数据库和分析平台(TCMSP)、人类基因数据库(GeneCa... 详细信息

目的:探究葛根治疗肝损伤的有效成分、靶标和作用通路,为葛根用于肝损伤的治疗提供理论依据。方法:基于中医药整合药理学网络计算平台(TCMIP)、中药综合资源数据库(TCMID)、中药系统药理数据库和分析平台(TCMSP)、人类基因数据库(GeneCards)等公共数据库和KEGG通路分析等网络药理学基本方法预测葛根治疗肝损伤的作用机制。结果:葛根主要活性成分靶点与肝损伤靶点具有交集,功能分析、富集分析和分子对接发现,刺芒柄花素、β-谷甾醇与雌激素受体1(ESR1),香豆雌酚、3′-甲氧基大豆黄素与PPARG与之间对接具有良好的亲和力,其中刺芒柄花素与ESR1之间作用力最强(-8.04 kcal/mol)。推断葛根治疗肝损伤的机制与ESR1和PPARG介导的路径相关。结论:葛根治疗肝损伤可能通过ESR信号通路、PPAR-γ激活和调节靶基因转录等发挥调节肝细胞的生长、分化和生理功能,减轻氧化应激性肝损伤和肝细胞凋亡的作用。

关键词：网络药理学葛根肝损伤活性成分作用机制

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Fluorescent Superlattices of Gold Nanoparticles:A New Class of Functional Materials

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Nano Research 2009年第3期2卷 220-234页

作者： Edakkattuparambil Sidharth shibu Madathumpady Abubaker Habeeb Muhammed Keisaku Kimura Thalappil Pradeep DST Unit on Nanoscience(DST UNS) Department of Chemistry and Sophisticated Analytical Instrument FacilityIndian Institute of TechnologyMadrasChennai 600036India Graduate School of Material Science University of Hyogo3-2-1 KotoKamigori-choAko-gun Hyogo 678-1297Japan

Fluorescent three-dimensional(3-D)superlattices of dansyl glutathione protected gold nanoparticles,with potential applications in molecular detection,have been synthesized at an air/water interface by controlling the pH of the nanoparticle *** number of fluorophores per nanoparticle was calculated to be~*** of the superlattice crystals were examined using scanning electron microscopy(SEM).Most of the crystals observed were triangular in ***-resolution transmission electron microscopy(HRTEM)and small angle X-ray scattering(SAXS)were used to study the packing of nanoparticles in these *** these studies showed that the nanoparticles were arranged in a face-centered cubic(fcc)pattern with a particle-particle distance(center-center)of~10.5 *** of the crystal morphologies with time was also *** fluorescence properties of these triangles were studied using confocal fluorescence imaging and confocal Raman mapping,which were in good agreement with the morphologies observed by *** superlattice exhibits near-infrared(NIR)absorption in the range 1100-2500 *** synthesis of such functional nanoparticle-based solids makes it possible to use them in novel *** utilized the fluorescence of dansyl glutathione gold superlattice crystals for the selective detection of bovine serum albumin(BSA),the major protein constituent of blood plasma,based on the selective binding of the naphthalene ring of the dansyl moiety with site I of BSA.

关键词： Periodic self-assembly dansyl glutathione fluorescent superlattice confocal fluorescence imaging selective binding

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Global achievements in sustainable land management

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International Soil and Water Conservation Research 2013年第1期1卷 1-10页

作者： Peter Motavalli Kelly Nelson Ranjith Udawatta shibu Jose Sougata Bardhan Environmental and Atmos.Sciences University of MissouriColumbiaMOUSA Division of Plant Sciences University of MissouriColumbiaMOUSA Center for Agroforestry University of MissouriColumbiaMOUSA

Identification and development of sustainable land management is urgently required because of widespread resource degradation from poor land use *** addition,the world will need to increase food production to meet the nutritional needs of a growing global population without major environmental *** climate change and its impacts on the environment is an additional factor to consider in identifying and developing sustainable land use *** objectives of this paper are to:(1)provide a background to the need for sustainable land management,(2)identify some of its major components,and(3)discuss some examples of sustainable land management systems that are being practiced around the *** common components of this type of management are:(1)understanding the ecology of land management,(2)maintenance or enhancement of land productivity,(3)maintenance of soil quality,(4)increased diversity for higher stability and resilience,(5)provision of economic and ecosystem service benefits for communities,and(6)social *** examples of sustainable land management systems are discussed to illustrate the wide range of systems that have been developed around the world including agroforestry,conservation agriculture,and precision agricultural *** technology,allowing for geater environmental measurement and for improved access and sharing of information,provides opportunities to identify and develop more sustainable land management practices and systems for the future.

关键词： Soil degradation Ecosystem services Diversity Soil quality Agroforestry Conservation agriculture Precision agriculture

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