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31.
Influence of ionic liquid composition on the stability of polyvinyl chloride‐based ionic liquid inclusion membranes in aqueous solution 下载免费PDF全文
Francisca Tomás‐Alonso Aurora M. Rubio Alfonso Giménez Antonia P. de los Ríos Maria J. Salar‐García Victor M. Ortiz‐Martínez Francisco J. Hernández‐Fernández 《American Institute of Chemical Engineers》2017,63(2):770-780
Membrane technology has gained significant importance with the incorporation of ionic liquids into their structure. This work shows the influence of ionic liquid composition on the stability of PVC‐based polymer ionic liquid inclusion membranes (PILIMs) in aqueous solution. Among the ILs investigated, those membranes which contain between 20 and 30%w/w of the least soluble, [OMIM+][PF6?] and [OMIM+][Ntf2?], exhibit losses of IL lower than 10%. For both ILs, the amount immobilized was maximum for the membranes with 30%w/w of IL (0.0838 and 0.0832 g, respectively). On the contrary, the ionic liquid loss increases as its solubility in water increase, reaching 99.52% when PILIMs are prepared with 70%w/w of [OMIM+][BF4?]. The results demonstrate that the stability of PILIMs depends on the solubility of the IL in the surrounding phase and the specific interaction between the IL and the polymeric support for PVC‐to‐IL ratios higher than 30%w/w. © 2016 American Institute of Chemical Engineers AIChE J, 63: 770–780, 2017 相似文献
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Celina Cziepluch Elisabeth Kordes Aurora Pujol Jean-Claude Jauniaux 《Yeast (Chichester, England)》1996,12(14):1471-1474
The complete sequence of a 40 247 bp DNA segment located on the left arm of chromosome X of Saccharomyces cerevisiae has been determined and analysed. The sequence encodes the 5′ coding region of the URA2 gene and 18 open reading frames of at least 100 amino acids. Ten of these correspond to known genes, whereas eight correspond to new genes. In addition, the sequence contains a tRNA-Ala gene, a tRNA-Asp gene, a Ty4 transposable element and three delta elements. The sequence has been deposited in the EMBL databank under Accession Numbers: Z49405, Z49404, Z49403, Z49402, Z49401, Z49400, Z49399, Z49398, Z49397, Z49396, Z49394, Z49392, Z49391, Z49390, Z49389, Z49387, Z49386, Z49385. 相似文献
35.
Nicole Bussola Bruno Papa Ombretta Melaiu Aurora Castellano Doriana Fruci Giuseppe Jurman 《International journal of molecular sciences》2021,22(16)
We introduce here a novel machine learning (ML) framework to address the issue of the quantitative assessment of the immune content in neuroblastoma (NB) specimens. First, the EUNet, a U-Net with an EfficientNet encoder, is trained to detect lymphocytes on tissue digital slides stained with the CD3 T-cell marker. The training set consists of 3782 images extracted from an original collection of 54 whole slide images (WSIs), manually annotated for a total of 73,751 lymphocytes. Resampling strategies, data augmentation, and transfer learning approaches are adopted to warrant reproducibility and to reduce the risk of overfitting and selection bias. Topological data analysis (TDA) is then used to define activation maps from different layers of the neural network at different stages of the training process, described by persistence diagrams (PD) and Betti curves. TDA is further integrated with the uniform manifold approximation and projection (UMAP) dimensionality reduction and the hierarchical density-based spatial clustering of applications with noise (HDBSCAN) algorithm for clustering, by the deep features, the relevant subgroups and structures, across different levels of the neural network. Finally, the recent TwoNN approach is leveraged to study the variation of the intrinsic dimensionality of the U-Net model. As the main task, the proposed pipeline is employed to evaluate the density of lymphocytes over the whole tissue area of the WSIs. The model achieves good results with mean absolute error 3.1 on test set, showing significant agreement between densities estimated by our EUNet model and by trained pathologists, thus indicating the potentialities of a promising new strategy in the quantification of the immune content in NB specimens. Moreover, the UMAP algorithm unveiled interesting patterns compatible with pathological characteristics, also highlighting novel insights into the dynamics of the intrinsic dataset dimensionality at different stages of the training process. All the experiments were run on the Microsoft Azure cloud platform. 相似文献
36.
The study of university?Cindustry (U?CI) relations has been the focus of growing interest in the literature. However, to date, a quantitative overview of the existing literature in this field has yet to be accomplished. This study intends to fill this gap through the use of bibliometric techniques. By using three different yet interrelated databases??a database containing the articles published on U?CI links, which encompass 534 articles published between 1986 and 2011; a ??roots?? database, which encompasses over 20,000 references to the articles published on U?CI relations; and a ??influences?? database which includes more than 15,000 studies that cited the articles published on U?CI relations??we obtained the following results: (1) ??Academic spin offs??, ??Scientific and technological policies?? and (to a greater extent) ??Knowledge Transfer Channels?? are topics in decline; (2) ??Characteristics of universities, firms and scientists??, along with ??Regional spillovers??, show remarkable growth, and ??Measures and indicators?? can be considered an emergent topic; (3) clear tendency towards ??empirical?? works, although ??appreciative and empirical?? papers constitute the bulk of this literature; (4) the multidisciplinary nature of the intellectual roots of the U?CI literature??an interesting blending of neoclassical economics (focused on licensing, knowledge transfer and high-tech entrepreneurship) and heterodox approaches (mainly related to systems of innovation) is observed in terms of intellectual roots; (5) the influence of the U?CI literature is largely concentrated on the industrialized world and on the research area of innovation and technology (i.e., some ??scientific endogamy?? is observed). 相似文献
37.
The ligand exchange reaction with pyridine is the standard procedure for the integration of colloidal semiconductor nanocrystals (NCs) in photovoltaic devices; however, for large sized and irregularly shaped branched NCs, such as CdSe@CdTe tetrapods, this procedure can lead to a considerable waste of materials and the aggregation of NCs in the colloidal solution, therefore resulting in the formation of an inhomogeneous film and low device performances. Here, we report on alternative post-deposition treatments with carboxylic acids on films of CdSe@CdTe tetrapod shaped NCs. This approach guarantees the removal of the insulating surfactant, necessary to obtain good charge transport among NCs, while preserving the film integrity. We perform a complete characterization of the nanocrystalline films treated with different carboxylic acids and demonstrate the successful integration of such films in photovoltaic devices, showing a doubled efficiency with respect to the standard ligand exchange procedure. Our approach represents a general route towards the development of NC based devices with improved performances and minimized waste of material. 相似文献
38.
Carolina Donate-López José Juan Jiménez-Moleón Aurora Bueno-Cavanillas 《Accident; analysis and prevention》2010,42(1):297-306
Background
This study was designed to separate the association of age, sex and helmet use with the risk of death for occupants of two-wheeled motor vehicles (TWMV) involved in crashes into its two theoretical components: severity of the crash and occupant resilience.Methods
We analyzed the retrospective cohort comprising all 48 016 pairs of drivers and passengers aged 14 years or more in TWMV involved in crashes with victims in Spain from 1993 to 2007 recorded in the Spanish traffic crash registry. The outcome (death or survival), age, sex and helmet use was known for both occupants. Adjusted relative risks (RR) for the association of age, sex and helmet with the risk of death were calculated with Poisson regression models.Results
Each 1-year increase in age was related with a 3% increase in the risk of death related with lower resilience. The severity-dependent RR of death was 1.84 for male sex and 0.86 for non-helmet use, and the resilience-dependent RR was 0.72 and 2.53, respectively.Conclusions
The direction and magnitude of the association between age, sex and helmet use and the risk of death of an occupant of a TWMV involved in a crash changed depending on which component of risk was considered: crash severity or occupant resilience. Specifically, female sex and non-helmet use seemed to be associated with crashes of lower severity, but together with increased age they were also related with lower resilience to the energy released in the crash, and therefore with a higher risk of death after adjustment for crash severity. This should be taken into account when assessing the association of individual factors with the risk of death after a crash. 相似文献39.
Kakisu E Irigoyen A Torre P De Antoni GL Abraham AG 《The Journal of dairy research》2011,78(4):456-463
A two-strain starter culture containing Lactobacillus plantarum CIDCA 83114, a potential probiotic strain isolated from kefir grains, and Streptococcus thermophilus CIDCA 321 was tested for the preparation of a fermented milk product. Kluyveromyces marxianus CIDCA 8154, a yeast with immunomodulatory properties was included to formulate a three-strain starter culture. Supernatants of enterohaemorragic Escherichia coli, shiga-toxin-producing strain, along with a two-strain or a three-strain starter culture were included in the medium of Vero-cell surface cultures. The results demonstrated that these combinations of microorganisms antagonize the cytopathic action of shiga toxins. The cell concentration of Lb. plantarum did not decrease during fermentation, indicating that the viability of this strain was not affected by low pH, nor did the number of viable bacteria change during 21 days of storage in either fermented products. The number of viable yeasts increases during fermentation and storage. Trained assessors analyzed the general acceptability of fresh fermented milks and considered both acceptable. The milk fermented with the two-strain starter culture was considered acceptable after two week of storage, while the product fermented with the three-strain starter culture remained acceptable for less than one week. The main changes in sensory attributes detected by the trained panel were in sour taste, milky taste and also in fermented attributes. The correlation between different sensory attributes and acceptability indicated that the panel was positively influenced by milky attributes (taste, odour, and flavour) as well as the intensity of flavour. In conclusion, the two-strain starter culture would be the more promising alternative for inclusion of that potential probiotic lactobacillus in a fermented milk product. 相似文献
40.
Carmen Díez Marqués Laura Coll Hellín Leonor Gutiérrez Ruiz Aurora Zapata Revilla 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1994,198(1):60-65
In the present work the composition of apple liqueurs has been analysed, since the consumption of these beverages in Spain has increased during the last years. Twenty-five samples, belonging to the most representative five brands of the Spanish market have been analysed. The following determinations were carried out: alcoholic grade, total acidity, methanol, furfurol, dry extract, reducing sugars, sucrose, ash contact, macroelements (Na, K, Ca, Mg) and microelements (Cu, Fe, Mn, Zn). These parameters enable the quality evaluation of these beverages and contribute to their characterization with respect to the fruit used in their elaboration. To complete the experimental study, a BMDP 7M discriminant statistical analysis has been applied to the results obtained. The variables that best discriminate the groups have been determined and all the samples have been classified and differentiated.
Analytisches Studium der Apfelsaftliköre
Zusammenfassung Es wurde die Zusammensetzung von Apfelsaftlikören analysiert, weil diese Getränke öfter in Spanien getrunken werden. Fünfundzwanzig Proben von fünf bestimmten, spanischen Markengetränken wurden analysiert. Es wurden folgende Bestimmungen ausgeführt: Alkoholkonzentration, Gehalt an Säure, Methanol, Extrakt, Zucker, Sucrose, Asche, Macroelemente (Na, K, Ca, Mg) und Mikroelemente (Cu, Fe, Mn, Zn). Diese Parameter erlauben die Qualität dieser Getränke zu schätzen und ihre Charakterisierung auf Grund des Fruchtgehaltes. Weiterhin wurde eine BMDP 7M diskriminant-statistische Analyse der Resultate angewandt. Die diskriminant-Variablen der Gruppe wurden bestimmt und alle Proben konnten klassifiziert und unterschieden werden.相似文献