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Assessment of soil degradation and chemical compositions in Rwandan tea-growing areas

Geoscience Frontiers 2011年第4期2卷 599-607页

作者： Jean de la Paix Mupenzi lanhai Li Jiwen Ge Achal Varenyam Gabriel Habiyaremye Nzayisenga Theoneste k.manzi Emmanuel xinjiang Institute of Ecology and Geography Chinese Academy of Sciences State Key Laboratory of Oasis Ecology and Desert Environment 818 Beijing South Road Urumqi Xinjiang 830011 China School of Environmental Studies China University of Geosciences 388 Lumo Road Hongshan Administrative District Wuhan Hubei 430074 China Hubei k.y laboratory of Wetland Evolution ＆ Eco-Restoration 388 Lumo Road Hongshan Administrative District Wuhan Hubei 430074 China

This study has focused on the processes of soil degradation and chemical element concentration in tea-growing regions of Rwanda,*** degradation accelerated by erosion is caused not only by topography but also by human *** soil degradation involves both the physical loss and reduction in the amount of topsoil associated with nutrient *** samples were collected from eleven tropical zones in Rwanda and from variable depth within each collecting *** these,Samples from three locations in each zone were analyzed in the laboratory,with the result that the pH of all soil samples is shown to be less than 5（pH〈5） with a general average of *** elements such as iron（Fe）, copper（Cu）,manganese（Mn）,and zinc（Zn） are present in high concentration *** contrast calcium （Ca） and sodium（Na） are present at low-level concentrations and carbon（C） was found in minimal *** addition,elements derived from fertilizers,such as nitrogen（N）,phosphorous（P）,and potassium（k. which is also from minerals such as feldspar,are also present in low-level concentrations. The results indicate that the soil in certain Rwandan tea plantations is acidic and that this level of pH may help explain,in addition to natural factors,the deficiency of some elements such as Ca,Mg,P and *** use of chemical fertilizers,land use system and the location of fields relative to household plots are also considered to help explain why tea plantation soils are typically degraded.

关键词： Chemical elements Fertilizer use pH Soil degradation Tea plantations

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Nano-Microencapsulation and Controlled Release of Linoleic Acid in Biopolymer Matrices: Effects of the Physical State, Water Activity, and Quercetin on Oxidative Stability

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Journal of Encapsulation and Adsorption Sciences 2012年第1期2卷 1-10页

作者： Gilles k. k.uassi Vinod k. Teriveedhi Christopher L. Milby Tarab Ahmad Mark.S. Boley Netk.l M. Gowda Ronald J. Terry Department of Chemistry Western Illinois University Macomb USA Department of Physics Western Illinois University Macomb USA

In this study, linoleic acid (la) was encapsulated in the presence or absence of quercetin into a dual polymer system of whey protein and k.ppa-carrageenan using power ultrasound. Atomic Force Microscopy (AFM) and FlowCam imaging technology were used for imaging and size determination of nano-and micro-capsules. Differential scanning calorimeter (DSC) was used to determine the glass transition temperature (Tg) of the freeze-dried nanocapsules. In order to examine the effect of water activity (aw) on the release profile of the encapsulated la, the nanocapsules were equilibrated over saturated salt solution conditions corresponding to the range of aw between 0.333 and 0.769 in evacuated desiccators at room temperature. Gravimetric measurements of the steady state linoleic acid (la) contents were conducted. The anti-oxidant activity of quercetin and the stability of encapsulated la toward long term and thermally induced rancidity was investigated. The capsules were in the nanosize regime and 83% of the la was effectively encapsulated. Furthermore, at aw of 0.764, the highest percentage of la (74%) was released from the expelling nanocapsules. Quercetin was found to exhibit protective antioxidant effect against time-dependent oxidation and thermally induced rancidity of la. Water activity values of 0.662 and 0.764 provided ideal humidity and pressure conditions for sustained release of nanoencapsulated la at room temperature.

关键词： Nanoencapsulation Microencapsulation k.ppa-Carrageenan Quercetin rancidity Antioxidant

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ON　k.Smooth,k.Very　Smooth　and　k.Strongly　Smooth　Banach　Spaces

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Journal of Harbin Institute of Technology(New Series) 1998年第1期5卷 6-9页

作者： Su Ya la Tu WU Congxin

ＯＮｋ－Ｓｍｏｏｔｈ，ｋ－ＶｅｒｙＳｍｏｏｔｈａｎｄＫ－ＳｔｒｏｎｇｌｙＳｍｏｏｔｈＢａｎａｃｈＳｐａｃｅｓＷＵＣｏｎｇｘｉｎ（吴从）（Ｄｅｐｔ．ｏｆＭａｔｈｅｍａｔｉｃｓ，ＨａｒｂｉｎｌｎｓｔｉｔｕｔｅｏｆＴｅｃｈ... 详细信息

ＯＮｋ－Ｓｍｏｏｔｈ，ｋ－ＶｅｒｙＳｍｏｏｔｈａｎｄＫ－ＳｔｒｏｎｇｌｙＳｍｏｏｔｈＢａｎａｃｈＳｐａｃｅｓＷＵＣｏｎｇｘｉｎ（吴从）（Ｄｅｐｔ．ｏｆＭａｔｈｅｍａｔｉｃｓ，ＨａｒｂｉｎｌｎｓｔｉｔｕｔｅｏｆＴｅｃｈｎｏｌｏｇｙ，Ｈａｒｂｉｎ，１５０...

关键词： k.smooth spaces k.very smooth (k.very convex) spaces k.strongly smooth (k. strongly convex) spaces k.exposed (k.strongly exposed

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Dynamically generated resonances

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Chinese Physics C 2009年第12期33卷 1132-1139页

作者： E. Oset A. Ramos S. Sark.r 孙宝玺 M.J.Vicente Vacas P. Gonzalez J. Vijande D. Jido T. Sek.hara A. Martinez-Torres k. k.emchandani Departamento de Física Teórica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Aptdo. 22085 46071 Valencia Spain Departament d'Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos Universitat de Barcelona 08028 Barcelona Spain Variable Energy Cyclotron Centre 1/AF Bidhannagar Kolkata 700064 India Institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Departamento de Física Atomica Molecular y Nuclear and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Aptdo. 22085 46071 Valencia Spain Yuk.wa Institute for Theoretical Physics Kyoto University Kyoto 606-8502 Japan Department of Physics Kyoto University Kyoto 606-8502 Japan Centro de Física Computacional Departamento de Física Universidade de Coimbra P-3004-516 Coimbra Portugal

In this talk.I report on recent work.related to the dynamical generation of baryonic resonances, some made up from pseudoscalar meson-baryon, others from vector meson-baryon and a third type from two meson-one baryon systems. We can establish a correspondence with k.own baryonic resonances, reinforcing conclusions previously drawn and bringing new light on the nature of some baryonic resonances of higher mass.

关键词： dynamically generated resonances chiral dynamics hidden gauge formalism for vector mesoninteraction

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The Use of Light Diffracted from Grating Etched onto the Back.ide Surface of an Atomic Force Microscope Cantilever Increases the Force Sensitivity

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Journal of Surface Engineered Materials and Advanced Technology 2013年第4期3卷 29-35页

作者： Sergey k. Sek.tsk.i Mounir Mensi Andrey G. Mik.aylov Giovanni Dietler laboratoire de Physique de la Matière Vivante IPSB Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Swit- zerland.

A reflecting diffraction grating has been etched onto the back.ide of a standard cantilever for atomic force microscopy, and the diffracted light has been used to monitor the angular position of the cantilever. It is shown experimentally that for small angles of incidence and for large reflection angles, the force sensitivity can be improved by few times when an appropriate detection scheme based on the position sensitive (duolateral) detector is used. The first demonstration was performed with a one micron period amplitude diffraction grating onto the back.ide of an Al-coated cantilever etched by a focused ion beam milling for the experiments in air and an analogous 600 nm-period grating for the experiments in air and in water.

关键词： Atomic Force Microscopy Force Measurement Sensitivity Diffraction Grating

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Antibacterial compounds from Rutaceae with activities against Flavobacterium columnare and Streptococcus iniae

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Journal of Agricultural Chemistry and Environment 2013年第4期2卷 90-100页

作者： k.mudini M. Meepagala k.vin k. Schrader Charles L. Burandt University of Mississippi National Center for Natural Products Research University MS USA USDA-ARS Natural Products Utilization Research Unit University MS USA

From the ethyl acetate extract of Murraya k.enegii (Rutaceae) leaves, isomahanine (1) and mahanine (2) were isolated that showed antibacterial activity towards Flavobacterium columnare and Streptococcus iniae which caused columnaris disease and streptococcosis respectively. Isomahanine was found to have the strongest activity against F. columnare (isolate ALM-00-173) and S. iniae (isolate la94-426) based on 24-h 50% inhibition concentration (IC50) and minimum inhibition concentration (MIC). Although compound (7), a nicotinamide isolated from Amyris texana had the lowest MIC (2.8 ± 0 mg/L) of any of the test compounds against F. columnare, the 24-h IC50 of 14.8 ± 0.6 mg/L was higher than that of isomahanine and subsequently the 24-h IC50 RDC values for (7) were almost a magnitude of order higher than those obtained for isomahanine. Isomahanine also had the strongest activity against S. iniae, with a 24-h IC50 of 1.3 ± 0.1 mg/L and MIC of 3.5 ± 0 mg/L, respectively.

关键词： Murraya k.enigii Amyris texana Piper nigrum Columnaris Disease Flavobacterium columnare Streptococcosis Streptococcus iniae Aquaculture

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(la_(1-2x)Sm_(x)Nd_(x))_(2)AlTaO_(7)氧化物的热物理性能

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中国陶瓷 2022年第1期58卷 43-48页

作者：冉书明重庆水利电力职业技术学院智能制造学院重庆402160

以高纯度la_(2)O_(3)、Sm_(2)O_(3)、Nd_(2)O_(3)、Al_(2)O_(3)和Ta_(2)O_(5)为原材料,采用多步高温固相烧结法制备了(la_(1-2x)Sm_(x)Nd_(x))_(2)AlTaO_(7)陶瓷材料。对其相组成、显微形貌、元素组成物理性能进行了研究。结果表明,试验合成的氧化物具有单一的氟铝镁钠石结构。其显微组织结构致密,晶界清晰,元素种类和摩尔比与各自的化学式基本一致。由于掺杂增加了声子的散射程度,该类氧化物的热导率明显低于la_(2)AlTaO_(7),但由于Sm^(3+)和Nd^(3+)的引入降低了氧化物的容许系数,使得(la_(0.6)Sm_(0.2)Nd_(0.2))_(2)AlTaO_(7)的热导率略大于(la_(0.6)Sm_(0.1)Nd_(0.1))_(2)AlTaO_(7)。由于掺杂离子较低的半径,其热膨胀系数相比la_(2)AlTaO_(7)明显降低,而掺杂离子较高的电负性,使得(la_(0.6)Sm_(0.2)Nd_(0.2))_(2)AlTaO_(7)的热膨胀系数略大于(la_(0.8)Sm_(0.1)Nd_(0.1))_(2)AlTaO_(7)。该类氧化物的热导率和热膨胀系数满足热障涂层的要求。

关键词：稀土钽铝酸盐热障涂层热导率热膨胀系数

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No association of the cytotoxic T-lymphocyte associated gene CTla4 +49A/G polymorphisms with Crohn's disease and ulcerative colitis in Hungarian population samples

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World Journal of Gastroenterology 2007年第15期13卷 2205-2208页

作者： Lili Magyari Bernadett Faragó Judit Bene k.talin Horvatovich Lilla lak.er Márta Varga Mária Figler Beáta Gasztonyi Gyula Mózsik.Béla Melegh Department of Medical Genetics and Child Development University of Pécs PécsHungary MTA PTE Clinical Genetics Research Group of the Hungarian Academy of Sciences at the University of Pécs Pécs Hungary Mark.sovszk. Hospital Department of Medicine and Gastroenterology SzombathelyHungary Réthy Pál Hospital 3rd Department of Medicine and Gastroenterology BékéscsabaHungary Department of Medicine School of Medicine University of PécsPécsHungary Department of Gastroenterology Zala County Hospital ZalaegerszegHungary

AIM： The goal of the current work.was to analyse the prevalence of the ＋49A/G variant of the cytotoxic T-lymphocyte antigen 4 gene （CTla4） in Hungarian patients with Crohn＇s disease （CD） and ulcerative colitis （UC）. METHODS： A total of 130 unrelated subjects with CD and 150 with UC, and 170 matched controls were genotyped for the single nucleotide polymorphism （SNP）. The genotypes were determined by using PCR/RFLP test. RESULTS： The G allele frequency and the prevalence of the GG genotype were 38.1% and 12.3% in the CD group, 40.6% and 18.6% in the UC patients, and 37.4% and 15.9% in the control group, respectively. CONCLUSION： The results of the current study show that carriage of the ＋49G SNP in heterozygous or in homozygous form does not confer risk.either for CD or for UC in the Hungarian population.

关键词： Cytotoxic T-lymphocyte antigen 4 Crohn's disease Ulcerative colitis Inflammatory bowel disease

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Transport Properties of the layer Manganite la1.5Ca1.5Mn2-xFexO7

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World Journal of Condensed Matter Physics 2011年第4期1卷 153-156页

作者： Anjali k.ishnamurthy M. P. Sharma Bipin k. Srivastava 不详

layered perovsk.te manganite ceramics with a nominal chemistry la1.5Ca1.5Mn2-xFexO7(x = 0.0, 0.05, 0.1, 0.3, 0.5) were prepared using sol-gel method. The manganese ions are highly mixed states of Mn3+ and Mn4+. It is found that the Mn3+/Mn4+ ratio decreases with the Fe doping content increasing. The conductivity and magnetoresistance (MR) were studied. The sample of x = 0.05 shows metal insulator transition (MIT) at 135 k. The MIT peak.temperature (Tp) shifts towards higher temperature with increasing applied magnetic field. All the samples can be well fitted to the variable-range hopping (VRH) model. The maximum value of MR (%) [ρ(0) - ρ(H)]/ρ(0) × 100 for x = 0.05 is 34% (105 k. 7 k.e).

关键词： layered Perovsk.te M-I Transition GMR

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一起深入了解传播的基础和特性电离层的构成

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现代通信 2015年第1期 61-63页

作者： k.la 邵业传

本文关注电离层自身，主要讨论的是电离层的形成。请注意，电离层是个复杂的系统，关于这个话题已有大量的著作来介绍，本文我们通过几个主要的特性来大致讨论下这个话题。不过文章中会有一些涉及到很基础、却又很重要的理论概念，希望... 详细信息

本文关注电离层自身，主要讨论的是电离层的形成。请注意，电离层是个复杂的系统，关于这个话题已有大量的著作来介绍，本文我们通过几个主要的特性来大致讨论下这个话题。不过文章中会有一些涉及到很基础、却又很重要的理论概念，希望这些理论能够澄清一些在业余无线电文献中不时出现的误解。

关键词：电离层特性基础传播业余无线电

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