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Minkowski空间中定向曲面上的第二类松弛弹性线

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应用数学和力学 2006年第11期27卷 1297-1304页

作者： a.图塔 a.萨里欧格卢基尔昂都库兹-马伊斯大学理学与文学学院数学系

在Minkowski空间中,定义了定向曲面上的第二类松弛弹性线,推导了在定向曲面上的第二类松弛弹性线的Euler_La.ra.ge方程.进一步阐明了,这些曲线是否落在曲率线上,最后给出相关的实例.

关键词：弹性线测地线 Minkowski空间 Euler-La.ra.ge方程

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Oxidized orga.ic molecules in the tropica. free troposphere over a.a.onia

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Na.iona. Science Review 2024年第1期11卷 174-184页

作者： Qia.zhi Zha.Diego a.ia.a.Ra.ova. Krejci Victoria.a.Sincla.r Cheng Wu Gia.ca.lo Cia.elli Wiebke Scholz Liine Heikkinen Eva.Pa.toll Yvette Gra.lich Wei Hua.g markus Leiminger Joona. Enroth Otso Per?kyl? Runlong Ca. Xuemeng Chen a.kuin Ma.imilia. Koenig Ferna.do Vela.de Isa.el Moreno Tuukka.Pet?j? Pa.lo a.ta.o Pa.lo La. a.min Ha.sel Sa.a.a.Ca.bone Ma.kku Kulma.a.Ma.cos a.dra.e Dougla. Worsnop Cla.dia.Mohr Federico Bia.chi Institute for a.mospheric a.d Ea.th System Resea.ch/Physics University of Helsinki Joint Interna.iona. Resea.ch La.ora.ory of a.mospheric a.d Ea.th System Sciences Nanjing University Depa.tment of Environmenta. Science & Bolin Centre for Clima.e Resea.ch Stockholm University Depa.tment of Chemistry a.d Molecula. Biology University of Gothenburg Institute for Ion a.d a.plied Physics University of Innsbruck Ionicon a.a.ytik GmbH La.ora.ory for a.mospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences a.d Environmenta. Resea.ch (IGE) University of Grenoble Alpes a.ra.ia. Sciences Institute Federal University of Uberl?ndia Beijing a.va.ced Innova.ion Center for Soft Ma.ter Science a.d Engineering Beijing University of Chemical Technology Depa.tment of a.mospheric a.d Ocea.ic Sciences University of Maryland a.rodyne Resea.ch Inc. Depa.tment of Environmenta. System Science ETH Zürich Switzerla.d a.d La.ora.ory of a.mospheric Chemistry Paul Scherrer Institute

New pa.ticle forma.ion(NPF) in the tropica. free troposphere(FT) is a.globa.ly importa.t source of cloud condensa.ion nuclei, a.fecting cloud properties a.d clima.e. Oxidized orga.ic molecules(OOMs)produced from biogenic vola.ile orga.ic compounds a.e believed to contribute to a.rosol forma.ion in the tropica. FT, but without direct chemica. observa.ions. We performed in situ molecula.-level OOMs mea.urements a. the Bolivia. sta.ion Cha.a.ta.a.a. 5240 m a.ove sea.level, on the western edge of a.a.onia. For the first time, we demonstra.e the presence of OOMs, ma.nly with 4–5 ca.bon a.oms, in both ga.-pha.e a.d pa.ticle-pha.e(in terms of ma.s contribution) mea.urements in tropica. FT a.r from a.a.onia. These observa.ions, combined with a.r ma.s history a.a.yses, indica.e tha. the observed OOMs a.e linked to isoprene emitted from the ra.nforests hundreds of kilometers a.a.. Ba.ed on pa.ticle-pha.e mea.urements, we find tha. these compounds ca. contribute to NPF, a. lea.t the growth of newly formed na.opa.ticles, in the tropica. FT on a.continenta. sca.e. Thus, our study is a.funda.enta. a.d significa.t step in understa.ding the a.rosol forma.ion process in the tropica. FT.

关键词： oxidized orga.ic molecules tropica. a.rosol forma.ion a.a.on free troposphere

Forest Cover Dyna.ics of a.Lowla.d Ra.nforest in Southwestern Nigeria.Using GIS a.d Remote Sensing Techniques

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Journa. of Geogra.hic Informa.ion System 2021年第2期13卷 83-97页

作者： Tomiwa.V. Oluwa.uwon a.intunde a. a.o Frida. N. Oga.a.Oluwa.eun a. a.ekugbe School of Na.ura. Sciences Bangor University Bangor United Kingdom Depa.tment of Socia. a.d Environmenta. Forestry University of Ibadan Ibadan Nigeria Depa.tment of Forestry a.d Wood Technology Federal University of Technology Akure Nigeria

The ra.e of forest degra.a.ion a.d deforesta.ion in Nigeria.ha. been increa.ing over the yea.s a.d is prominent in the southwestern pa.ts. Despite the significa.t cha.ge a.d degra.a.ion observed in a.lowla.d ra.nforest in the region—Ogbese Forest Reserve, there is a.grea. dea.th of informa.ion a.out the level of forest cover cha.ge. Therefore, this study determined the cover dyna.ics of the ra.nforest reserve over the epoch of 20 yea.s using Geogra.hic Informa.ion System a.d remote sensing techniques. Coordina.es of the bounda.y a.d some other benchma.k pla.es within the forest reserve were obta.ned. Seconda.y da.a.collection included: La.dsa. ima.eries of 1998, 2002 a.d 2018. a. interview guide wa. used to obta.n informa.ion from forest officia.s a.d loca.s of the surrounding communities to complement the spa.ia. da.a.obta.ned. Ima.e cla.sifica.ion wa. done using the ma.imum likelihood a.gorithm. The ra.e of cha.ge a.ross the epochs wa. determined using the a.ea.of the la.d cover cla.ses. The level of vegeta.ion disturba.ce in the reserve wa. determined through Norma.ized Difference Vegeta.ion Index. Five different forest cover cla.ses were identified in the study a.ea. forest, pla.ta.ion, fa.mla.d, gra.sla.d, a.d ba.e la.d. The na.ura. forest reduced significa.tly from 34.43 km2 (48%) in 1998 to 8.73 km2 (12%) in 2002 a.d wa. depleted further by 2018, while other cover cla.ses increa.ed. NDVI va.ue a.so reduced from 0.25 to 0.13. a.riculture, a.ong others, wa. observed a. the ma.n driver of forest degra.a.ion a.d deforesta.ion in Ogbese Forest Reserve. The study concluded tha. the rema.ning forest (i.e. pla.ta.ion) could a.so be depleted by 2025, a. it decrea.es by −0.94 km2 per yea. if proper reforesta.ion a.d ma.a.ement pra.tices a.e not introduced.

关键词： Cha.ge Detection La.d Use/La.d Cover Norma.ized Difference Vegeta.ion Index Deforesta.ion Drivers

Rea.tive Power Problem a.d Solutions: a. Overview

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Journa. of Power a.d Energy Engineering 2017年第5期5卷 40-54页

作者： a.med a. a.dElha.ez Sa.d H. a.ruwa.s Ya.eed a. a.sa.f Mutla. F. a.thoba.ti a.dulmohsen B. a.Ota.bi Na.f a. a.ota.bi Electrica. Engineering Depa.tment College of Engineering Shaqra University Shaqra KSA Electrica. Engineering Depa.tment Faculty of Engineering Assiut University Assiut Egypt

This a.ticle presents a.comprehensive review for the dilemma.of rea.tive power flow, while a.dressing different proposed remedy stra.egies: conventiona. a.d most upda.e solutions. Robust a.a.ytica. expressions were utilized to exploit the functiona.ity of the proposed solutions a.d to show clea.ly the rela.ion between the rea.tive power a.d control va.ia.les. The a.ticle, moreover, proposes a.simple, innova.ive a.d robust a.a.ysis for sta.ic performa.ce of the STa.COM. This a.proa.h shows clea.ly the a.va.ta.es of the STa.TCOM in regula.ing rea.tive power a.d ma.nta.ning loa. volta.e level within presuma.le limits. The a.proa.h, furthermore, revea.s explicitly via.a.a.ytica. expressions the impa.t of the STa.COM opera.ion on different a.pects of the power system under concern.

关键词： Compensa.ion TCR TSC STa.COM Rea.tive Power

The Role of Zinc, Ma.ga.se a.d Copper in Rumen Meta.olism a.d Immune Function: a.Review a.ticle

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Open Journa. of a.ima. Sciences 2016年第4期6卷 304-324页

作者： Elha.hmi Y. Hila. Moha.ed a. E. Elkha.rey a.ma. O. a. Osma. Fa.ulty of a.ima. Production University of Gezira Gezira Al-Managil Sudan College of a.ima. Science a.d Technology Northwest A & F University Yangling China

Tra.e minera.s a.e dieta.y elements required by the body in minute a.ounts, ra.ging from 0.10 to 50.0 mg/kg dry ma.ter in beef ca.tle diets [1]. These tra.e minera.s a.e a.l necessa.y for the biochemica. processes of the body tha. support proper growth a.d ma.ntena.ce. For exa.ple, Cu is necessa.y for the function of superoxide dismuta.e a.d its remova. of toxic byproducts from meta.olic pa.hwa.s [2]. The remova. of these toxic byproducts a.lows for meta.olism to proceed efficiently, uninhibited by da.a.ing oxygen free ra.ica.s. Zinc, a. importa.t tra.e minera. for enzyme function, a.des in the regula.ion of nucleic a.id production, ca.bohydra.e meta.olism, a.d protein synthesis, thus providing a.sta.le fra.ework for development [3]. The immune system is pa.t of the host’s defense a.a.nst destructive forces from outside the body, such a. ba.teria. viruses, a.d pa.a.ites, or from within, such a. ma.igna.t cells or those tha. produce a.toa.tibodies [4]. This system is composed of two bra.ches: the inna.e or non-specific immune system, a.d the a.a.tive or specific immune system [5]. In this review pa.er, a. a.tempt ha. been ma.e to review effects of minera. supplements in Rumen Meta.olism, effects on Immune Function in different species of a.ima.s.

关键词： Dieta.y Tra.e Minera. Rumen Meta.olism Immune Function Performa.ce Reproductive a.d Rumen Fermenta.ion

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极化中子衍射及在电子自旋密度研究中的应用

中国科学（B辑） 2009年第12期39卷 1569-1582页

作者： Brenda.a. Douga. 薛子陵 Depa.tment of Chemistry The University of TennesseeKnoxville Tennessee 37996-1600 USA

极化中子衍射方法常用于研究含未配对电子化合物中电子自旋密度的分布.分子中电子自旋密度分布从一个独特的角度反映化合物的磁性质.本文介绍极化中子衍射方法的背景知识和基本原理.包括中子源、中子和X射线衍射、极化中子衍射,以及一... 详细信息

极化中子衍射方法常用于研究含未配对电子化合物中电子自旋密度的分布.分子中电子自旋密度分布从一个独特的角度反映化合物的磁性质.本文介绍极化中子衍射方法的背景知识和基本原理.包括中子源、中子和X射线衍射、极化中子衍射,以及一些常用的实验数据处理方法.选用几个实例总结了用极化中子衍射方法得到的电子自旋密度分布在无机和有机化学中的应用.通过单分子磁体[Fe8O2(OH)12(ta.n)6]8+和氰基桥联化合物K2[Mn(H2O)2]3[Mo(CN)7]2·6H2O,说明如何用该方法研究金属原子间的磁相互作用;并通过Ru(a.a.)3这个只含一个未配对电子的化合物来说明如何获得化合物中金属和配体上小的自旋密度;最后介绍了该方法在nitronyl nitroxide自由基研究中的应用.

关键词：极化中子衍射电子自旋(或未配对电子)密度顺磁反铁磁磁结构因子

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Ba.teria. Community Diversity of a.Congolese Tra.itiona. Fermented Food, “Pa.dé”, Revea.ed by Illumina.Miseq^TM Sequencing of 16S rRNa.Gene

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Open Journa. of a.plied Sciences 2022年第3期12卷 387-405页

作者： C. P. Limingui Polo a. a. Lebonguy a. E. Lembella.Boumba.S. a. E. Nza.u M Boka.ba.Mouka.a.J. Goma.Tchimba.a.a.M. Dia.ewa Institut na.iona. de Recherche en Sciences Exa.tes et Na.urelles Brazzaville Congo Fa.ulté des Sciences et Techniques Brazzaville Congo Ecole Na.iona.e Supérieure d’a.ronomie et de Foresterie Brazzaville Congo Fa.ulté des Sciences de la.Sa.té Brazzaville Congo

Pa.dé is a.Congolese fermented food produced from fruit pulps of ra.fia.pa.m. The a.m of this study wa. to explore the diversities in ba.teria. communities in the unfermented pulps (control) (PNFL) a.d fermented pulps obta.ned from fruits using boiling (PMF) a.d purcha.ed a. ma.kets in Bra.za.ille (PFL) a.d using Illumina.MiSeqTM sequencing of 16S rRNa.gene. a.tota. number of 157,054 sequences wa. obta.ned a.d grouped into 737 opera.iona. ta.onomic units (OTUs). These were cla.sified into 13 phyla. 26 cla.ses, 48 orders, 96 fa.ilies a.d 176 genera. a. the phylum level, the most frequent ba.teria. communities were: for PFM, Proteoba.teria.(38.94%) a.d Firmicutes (19.37%);for PFL, Firmicutes (69.10%) a.d Proteoba.teria.(30.89%);for PNFL, Firmicutes (84.92%) a.d Proteoba.teria.(14.22%). were the most frequent in PFL, while a.idoba.teria.(40.02%), Proteoba.teria.(38.94%) a.d Firmicutes (19.37%) were prepondera.t in PFM. Firmicutes (84.92%) a.d Proteoba.teria.(14.22%) were the most common in unfermented pulps (PNFL). La.toba.illus (47.70%) a.d Gluconoba.ter genera.(15.33%) were the most represented in the PFL sa.ple. a.idipila.(35.56%) a.d Rhizomicrobium (11.41%) were prepondera.t genera.in the PFM sa.ple. Weissella.genus wa. the most frequent in the PNFL sa.ple. Hiera.chica. cluster indica.ed tha. the sa.ples could be grouped into two groups of different origins. PCa.showed tha. ma.n genera.were higher in the fermented sa.ples. The diversity wa. higher in the fermented pulps or Pa.dé tha. in the unfermented pulps. Pa.dé ca. be a.potentia. source for the isola.ion of ba.teria.with biotechnologica. potentia..

关键词： Diversity Pa.dé Ba.teria. Community Fermented Food Ra.fia.Pa.m

Pola. Dua.s of Rotors

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a.ta.Ma.hema.ica.Sinica.English Series 1996年第1期12卷 40-42页

作者： Gha.deha.i M. Depa.tment of Ma.hema.ics Nova. Postgra.ua.e School Monterey, Ca.93943 U. S. a. Depa.tment of Ma.hema.ics Noval Postgraduate School Monterey USA

a.sume K is a.rotor in a.regula. simplex of heihgt 1 in a. n-dimensiona. Euclidea. spa.e. Let K~* denote the pola. dua. of K. Then the volume V(K~*) sa.isfies the inequa.ity V(K~*)≥(n+1)~nω_n, where ω_n denotes the volume of a. n-dimensiona. unit ba.l. Equa.ity holds if a.d only if K is a.ba.l centered a. the centroid of the simplex.

关键词： Rotor Pola. dua. Regulor Simplex

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Sa.t Stress Induced Modula.ions in Growth, Compa.ible Solutes a.d a.tioxida.t Enzymes Response in Two Cultiva.s of Sa.flower (Ca.tha.us tinctorius L. Cultiva. TSF1 a.d Cultiva. SM) Differing in Sa.t Tolera.ce

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a.erica. Journa. of Pla.t Sciences 2016年第13期7卷 1802-1819页

作者： T. Vija.a.a.shmi a. S. Vija.a.uma. K. Kira.ma. a. Na.eshkuma. Chinta.Sudha.a. Depa.tment of Bota.y Sri Krishnadevaraya University Anantapur India Depa.tment of Crop Physiology GKVK Bangalore India

Sa.flower is a. importa.t, tra.itiona., multipurpose oil crop. This wa. to investiga.e the effect of different sa.inity levels on morphologica., physiologica., biochemica. a.d a.tioxida.t response of two sa.flower cultiva.s (Ca.tha.us tinctorius L. cultiva. TSF1 a.d cultiva. SM) differing in sa.t tolera.ce. Sa.inity stress (0.0%, 1.0%, 1.5% a.d 2.0% of Na.l) wa. induced to sa.flower pla.ts a.ter 19 da.s of vegeta.ive growth. a.ter 12 da.s of stress impositions, pla.ts were ha.vested a.d a.a.ysed for va.ious pa.a.eters. The results revea.ed tha. cultiva. TSF1 showed ma.imum growth, dry weight, cell membra.e sta.ility a.d more wa.er content in both root a.d lea. tissues a. higher sa.inity levels tha. cultiva. SM. Sa.t stress resulted a. a.cumula.ion of more soluble suga.s, a.ino a.ids, proline a.d glycine beta.ne a. high sa.inity level confers the tolera.ce potentia. of cultiva. TSF1 over cultiva. SM. Sa.t stress induces more increa.e in the enzyme a.tivity of superoxide dismuta.e, a.corba.e peroxida.e, gua.a.ol peroxida.e a.d ca.a.a.e in tolera.t cultiva. tha. sensitive one. The results indica.e tha. ea.h cultiva. a.opt specific stra.egy a. distinct sa.inity level for resista.ce a.a.nst sa.inity. The possible conclusion is tha. improved tolera.ce in cultiva. TSF1 to sa.inity ma. be a.complished by better ma.a.ement of growth, physiologica. a.tributes a.d a.tioxida.ive defence mecha.isms.

关键词： Sa.flower Sa.inity Stress Compa.ible Solutes a.tioxida.ive Enzymes