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21.
Qing-xue Kong Ling Li Blanca Martinez Paul Chen Roger Ruan 《Applied biochemistry and biotechnology》2010,160(1):9-18
The objective of this research was to develop large-scale technologies to produce oil-rich algal biomass from wastewater.
The experiments were conducted using Erlenmeyer flasks and biocoil photobioreactor. Chlamydomonas reinhardtii was grown in artificial media and wastewaters taken from three different stages of the treatment process, namely, influent,
effluent, and centrate. Each of wastewaters contained different levels of nutrients. The specific growth rate of C. reinhardtii in different cultures was monitored over a period of 10 days. The biomass yield of microalgae and associated nitrogen and
phosphorous removal were evaluated. Effects of CO2 and pH on the growth were also studied. The level of nutrients greatly influenced algae growth. High levels of nutrients
seem to inhibit algae growth in the beginning, but provided sustained growth to a high degree. The studies have shown that
the optimal pH for C. reinhardtii is in the range of 7.5. An injection of air and a moderate amount of CO2 promoted algae growth. However, too much CO2 inhibited algae growth due to a significant decrease in pH. The experimental results showed that algal dry biomass yield
reached a maximum of 2.0 g L−1 day−1 in the biocoil. The oil content of microalgae of C. reinhardtii was 25.25% (w/w) in dry biomass weight. In the biocoil, 55.8 mg nitrogen and 17.4 mg phosphorus per liter per day were effectively removed
from the centrate wastewater. Ferric chloride was found to be an effective flocculent that helps the algae settle for easy
harvest and separation from the culture media. 相似文献
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Mesoporous Silica Nanoparticles Decorated with Carbosilane Dendrons as New Non‐viral Oligonucleotide Delivery Carriers 下载免费PDF全文
Ángel Martínez Dr. Elena Fuentes‐Paniagua Dr. Alejandro Baeza Dr. Javier Sánchez‐Nieves Dr. Mónica Cicuéndez Dr. Rafael Gómez Dr. F. Javier de la Mata Dr. Blanca González Prof. María Vallet‐Regí 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(44):15651-15666
A novel nanosystem based on mesoporous silica nanoparticles covered with carbosilane dendrons grafted on the external surface of the nanoparticles is reported. This system is able to transport single‐stranded oligonucleotide into cells, avoiding an electrostatic repulsion between the cell membrane and the negatively charged nucleic acids thanks to the cationic charge provided by the dendron coating under physiological conditions. Moreover, the presence of the highly ordered pore network inside the silica matrix would make possible to allocate other therapeutic agents within the mesopores with the aim of achieving a double delivery. First, carbosilane dendrons of second and third generation possessing ammonium or tertiary amine groups as peripheral functional groups were prepared. Hence, different strategies were tested in order to obtain their suitable grafting on the outer surface of the nanoparticles. As nucleic acid model, a single‐stranded DNA oligonucleotide tagged with a fluorescent Cy3 moiety was used to evaluate the DNA adsorption capacity. The hybrid material functionalised with the third generation of a neutral dendron showed excellent DNA binding properties. Finally, the cytotoxicity as well as the capability to deliver DNA into cells, was tested in vitro by using a human osteoblast‐like cell line, achieving good levels of internalisation of the vector DNA/carbosilane dendron‐functionalised material without affecting the cellular viability. 相似文献
26.
Moncada-Hernandez H Baylon-Cardiel JL Pérez-González VH Lapizco-Encinas BH 《Electrophoresis》2011,32(18):2502-2511
Dielectrophoresis (DEP) is the motion of particles due to polarization effects in nonuniform electric fields. DEP has great potential for handling cells and is a non-destructive phenomenon. It has been utilized for different cell analysis, from viability assessments to concentration enrichment and separation. Insulator-based DEP (iDEP) provides an attractive alternative to conventional electrode-based systems; in iDEP, insulating structures are used to generate nonuniform electric fields, resulting in simpler and more robust devices. Despite the rapid development of iDEP microdevices for applications with cells, the fundamentals behind the dielectrophoretic behavior of cells has not been fully elucidated. Understanding the theory behind iDEP is necessary to continue the progress in this field. This work presents the manipulation and separation of bacterial and yeast cells with iDEP. A computational model in COMSOL Multiphysics was employed to predict the effect of direct current-iDEP on cells suspended in a microchannel containing an array of insulating structures. The model allowed predicting particle behavior, pathlines and the regions where dielectrophoretic immobilization should occur. Experimental work was performed at the same operating conditions employed with the model and results were compared, obtaining good agreement. This is the first report on the mathematical modeling of the dielectrophoretic response of yeast and bacterial cells in a DC-iDEP microdevice. 相似文献
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Blanca Rojas de Gáscue José Luis Prin Gilma Hernández Enrique M. Vallés Arnaldo T. Lorenzo Alejandro J. Müller 《Journal of Thermal Analysis and Calorimetry》2011,103(2):669-678
The application of the Successive Self-nucleation and Annealing (SSA) thermal fractionation technique can yield detailed information
of the structural changes induced in linear polyethylene by irradiation. The production of tertiary carbons during the crosslinking
reactions can be equivalent to the structural heterogeneity present in branched polyethylenes since in both cases interruption
of the linear crystallizable sequences occurs, and these are structural differences that can be easily detected by thermal
fractionation. We demonstrate how correlations between melting point and short chain branching content employed for branched
polymers can be useful to characterize the distribution of chain heterogeneity produced by crosslinking. As the radiation
dose is increased and the crosslinking content also increases, the distribution of chain heterogeneity gets broader as detected
by SSA. When the results are coupled with morphological observations made by transmission electron microscopy, valuable information
on the morphological changes produced by crosslinking can also be ascertained, since the distribution of lamellar thicknesses
substantially broadens with crosslinking. Such a broad distribution can also be predicted from SSA by simple calculations
performed employing a modified version of the Gibbs–Thomson equation and is expected on the basis of random crosslinking reactions. 相似文献
29.
Balbás IM Mendoza BE Fernández-Zertuche M Ordoñez M Linzaga-Elizalde I 《Molecules (Basel, Switzerland)》2011,17(1):151-162
We describe a protocol developed for the preparation of β-enaminoketones derived from 1,3-cyclohexanediones, and their subsequent reduction by sodium in THF-isopropyl alcohol to afford cis- and trans-3-aminocyclohexanols. 相似文献
30.
Vergara J Barberá J Serrano JL Ros MB Sebastián N de la Fuente R López DO Fernández G Sánchez L Martín N 《Angewandte Chemie (International ed. in English)》2011,50(52):12523-12528
What a core-ker! By the appropriate combination of promesogenic bent-core structures and the C(60) unit, lamellar polar liquid-crystal phases were induced. The supramolecular organization of the functional fullerene-based assemblies, the temperature range of the soft phase, the stabilization of the mesophase-like order at room temperature, and the molecular switching under an electric field can be tuned, depending on the molecular structure. 相似文献