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151.
Gastón Gutiérrez-Gamboa Eva P. Pérez-Álvarez Pilar Rubio-Bretón Teresa Garde-Cerdán 《International Journal of Food Science & Technology》2019,54(4):1160-1168
Edible mushrooms production presents a potential problem for the environment, due to the large amount of waste generated. These wastes contain nitrogenous matter, which could be used as biostimulant in plants. The aim of this work was to study the effect of waste waters, from the mushroom production process, applied at veraison and 1 week later to grapevine leaves, on grape volatile compounds over two vintages. The results evidenced that mushroom water treatment decreased the grape content of certain terpenoids, C13 norisoprenoids, benzenoid compounds and esters, increasing C6 compounds content during the first season. Treated mushroom water application slightly affected grape volatile composition. This was the treatment that least affected the content of grape volatile composition. Few differences were found after the biostimulation during the second vintage. The season was the dominant factor of grape volatile content variation compared to the treatment and their interaction. 相似文献
152.
Annexin homologues in the kingdoms of Planta and Protista were characterized by molecular sequence analysis to determine their phylogenetic and structural relationship with annexins of Animalia. Sequence fragments from 19 plant annexins were identified in sequence databases and composite sequences were also assembled from expressed sequence tags for Arabidopsis thaliana. Length differences in protein aminotermini and evidence for unique exon splice sites indicated that plant annexins were distinct from those of animals. A third annexin gene of Giardia lamblia (Anx21-Gla) was identified as a distant relative to other protist annexins and to those of higher eukaryotes, thus providing a suitable outgroup for evolutionary reconstruction of the family tree. Rooted evolutionary trees portrayed protist, plant, and Dictyostelium annexins as early, monophyletic ramifications prior to the appearance of closely related animal annexin XIII. Molecular phylogenetic analyses of DNA and protein sequence alignments revealed at least seven separate plant subfamilies, represented by Anx18 (alfalfa, previously classified), Anx22 (thale cress), Anx23 (thale cress, cotton, rape and cabbage), Anx24 (bell pepper and tomato p34), Anx25 (strawberry, horseradish, pea, soybean, and castor bean), Anx26-Zma, and Anx27-Zma (maize). Other unique subfamilies may exist for rice, tomato p35, apple, and celery annexins. Consensus sequences compiled for each eukaryotic kingdom showed some breakdown of the "annexin-fold" motif in repeats 2 and 3 of protist and plant annexins and a conserved codon deletion in repeat 3 of plants. The characterization of distinct annexin genes in plants and protists reflects their comparable diversity among animal species and offers alternative models for the comparative study of structure-function relationships within this important gene family. 相似文献
153.
Noelia Maldonado Vernica G. Vegas Oded Halevi Jose Ignacio Martínez Pooi See Lee Shlomo Magdassi Michael T. Wharmby Ana E. Platero‐Prats Consuelo Moreno Flix Zamora Pilar Amo‐Ochoa 《Advanced functional materials》2019,29(15)
This work presents the fabrication of 3D‐printed composite objects based on copper(II) 1D coordination polymer ( CP1 ) decorated with thymine along its chains with potential utility as an environmental humidity sensor and as a water sensor in organic solvents. This new composite object has a remarkable sensitivity, ranging from 0.3% to 4% of water in organic solvents. The sensing capacity is related to the structural transformation due to the loss of water molecules that CP1 undergoes with temperature or by solvent molecules' competition, which induces significant change in color simultaneously. The CP1 and 3D printed materials are stable in air over 1 year and also at biological pHs (5–7), therefore suggesting potential applications as robust colorimetric sensors. These results open the door to generate a family of new 3D printed materials based on the integration of multifunctional coordination polymers with organic polymers. 相似文献
154.
To the best of our knowledge, there is no work that has focused on analysing the development of the scientific production on women, peace and security. The main objective of this paper is to cover this research gap through a bibliometric analysis, that covers 95 years (1918–2013), of articles published in peer-reviewed journals extracted from the SCOPUS database. Bibliometric indicators and laws have been applied to better understand the patterns that govern the scientific literature on this realm. A gender perspective has also been implemented in the analysis. The analysis provides quantitative results based on 321 articles published by 478 authors in 210 scientific journals. The data showed the high dispersion of the literature, both in terms of authors and journals focused on the topic, and a low level of collaboration among both authors and institutions. Regarding the research topic, half of the papers were related to the impact of conflict on civilians and civil society. The implementation of a gender perspective shows that most of the first, second and third authors of the papers are women. In terms of methodologies, qualitative methodologies are the most relevant and women are more prolific applying these methodology. In terms of geographical region of the research, most of the studies have been performed by authors from institutions in Anglo-Saxon countries, and most of the fieldwork has been focused on the United States and the main areas of conflict in the world throughout history. Finally, important research opportunities are identified. 相似文献
155.
Fabrication of Highly Porous Mullite Materials 总被引:1,自引:0,他引:1
Rafael Barea Maria I. Osendi Pilar Miranzo José M. F. Ferreira 《Journal of the American Ceramic Society》2005,88(3):777-779
Porous mullite, formed by large spherical-shaped pores evenly distributed within a mullite matrix, was processed by a direct consolidation method based on the starch swelling properties. Materials with porosities up to 60 vol% and with an average pore size of ∼30 μm were prepared. Porosity matched the starch volume fraction for contents ≥45 vol%, while for lower contents the porosity was above the volume fraction of starch. Formation of crack like defects either surrounding or connecting pores occurred during the drying–sintering processes in the high starch content mullite. 相似文献
156.
John M. Hutchinson Salvador Montserrat Frida Romn Pilar Corts Lourdes Campos 《应用聚合物科学杂志》2006,102(4):3751-3763
Various methods of preparation of epoxy resin/clay mixtures, before the addition of the crosslinking agent and curing to form epoxy‐based polymer layered silicate (PLS) nanocomposites, have been investigated to determine their effect on the nanostructure. Organically modified montmorillonite clay was used, and the mixtures were prepared by both simple mixing and solvent‐based methods. X‐ray diffraction shows that intercalation of the resin into the clay galleries occurs for all clay loadings up to 25 wt % and for both preparation methods, but the dispersion of the clay in the resin, observed by optical microscopy, is significantly better for the solvent preparation method. Differential scanning calorimetry (DSC) shows that the intercalated resin has the same molecular mobility as the extra‐gallery resin, but suggests that the intercalated resin does not penetrate completely into the galleries. Prolonged storage of the resin/clay mixtures at room temperature leads to changes in the DSC response, as well as in the response to thermogravimetry, which are interpreted as resulting from homopolymerization of the epoxy resin, catalyzed by the onium ion in the modified clay. This confirms and explains the earlier observation of Benson Tolle and Anderson (J Appl Polym Sci 2004, 91, 89) that “conditioning” of the resin/clay mixtures at ambient temperature has a significant effect when the crosslinking agent is subsequently added, and indicates that the preparation method has important consequences for the nanostructure development in the PLS nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:3751–3763, 2006 相似文献
157.
Joan Guillem Mayans Helena Armengol-Relats Dr. Pilar Calleja Prof. Antonio M. Echavarren 《Israel journal of chemistry》2018,58(5):639-658
Gold(I)-catalyzed cycloisomerizations of 1,n-enynes proceed through electrophilic intermediates that can be trapped intra- or intermolecularly by a variety of hetero- and carbon nucleophiles to form complex skeletons in a single step. This review covers the efforts of our group towards the development of new reactions that have been successfully applied in the total synthesis of several natural terpenoids and related carbocyclic structures, as well as for the ready access to challenging linear acenes. 相似文献
158.
Hyperspectral data influenced by sample matrix: the importance of building relevant reference spectral libraries to map materials of interest
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James C. K. Dillon Leonardo Bezerra María del Pilar Sosa Peña Nicole M. Neu‐Baker Sara A. Brenner 《Microscopy research and technique》2017,80(5):462-470
Hyperspectral imaging (HSI) and mapping are increasingly used for visualization and identification of nanoparticles (NPs) in a variety of matrices, including aqueous suspensions and biological samples. Reference spectral libraries (RSLs) contain hyperspectral data collected from materials of known composition and are used to detect the known materials in experimental samples through a one‐to‐one pixel “mapping” process. In some HSI studies, RSLs created from raw NPs were used to map NPs in experimental samples in a different matrix; for example, RSLs created from NPs in suspension to map NPs in biological tissue. Others have utilized RSLs created from NPs in the same matrix. However, few studies have systematically compared hyperspectral data as a function of the matrix in which the NPs are found and its impact on mapping results. The objective of this study is to compare RSLs created from metal oxide NPs in aqueous suspensions to RSLs created from the same NPs in rat tissues following in vivo inhalation exposure, and to investigate the differences in mapping that result from the use of each RSL. Results demonstrate that the spectral profiles of these NPs are matrix dependent: RSLs created from NPs in positive control tissues mapped to experimental tissues more appropriately than RSLs created from NPs in suspension. Aqueous suspension RSLs mapped 0‐602 out of 500,424 pixels per tissue image while tissue RSLs mapped 689‐18,435 pixels for the same images. This study underscores the need for appropriate positive controls for the creation of RSLs for mapping NPs in experimental samples. 相似文献
159.
Chemically Resistant,Shapeable, and Conducting Metal‐Organic Gels and Aerogels Built from Dithiooxamidato Ligand
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Daniel Vallejo‐Sánchez Pilar Amo‐Ochoa Garikoitz Beobide Oscar Castillo Michael Fröba Frank Hoffmann Antonio Luque Pilar Ocón Sonia Pérez‐Yáñez 《Advanced functional materials》2017,27(15)
Metal‐organic gels (MOGs) appear as a blooming alternative to well‐known metal‐organic frameworks (MOFs). Porosity of MOGs has a microstructural origin and not strictly crystalline like in MOFs; therefore, gelation may provide porosity to any metal‐organic system, including those with interesting properties but without a porous crystalline structure. The easy and straightforward shaping of MOGs contrasts with the need of binders for MOFs. In this contribution, a series of MOGs based on the assembly of 1D‐coordination polymer nanofibers of formula [M(DTA)]n (MII: Ni, Cu, Pd; DTA: dithiooxamidato) are reported, in which properties such as porosity, chemical inertness, mechanical robustness, and stimuli‐responsive electrical conductivity are brought together. The strength of the M? S bond confers an unusual chemical resistance, withstanding exposure to acids, alkalis, and mild oxidizing/reducing chemicals. Supercritical drying of MOGs provides ultralight metal‐organic aerogels (MOAs) with densities as low as 0.03 g cm?3 and plastic/brittle behavior depending on the nanofiber aspect ratio. Conductivity measurements reveal a semiconducting behavior (10?12 to 10?7 S cm?1 at 298 K) that can be improved by doping (10?5 S cm?1). Moreover, it must be stressed that conductivity of MOAs reversibly increases (up to 10?5 S cm?1) under the presence of acetic acid. 相似文献
160.
Stimuli‐Responsive Materials: Chemically Resistant,Shapeable, and Conducting Metal‐Organic Gels and Aerogels Built from Dithiooxamidato Ligand (Adv. Funct. Mater. 15/2017)
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