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61.
62.
Sonia de Almeida Evaneide N. Lima Marisa S. Crespi Clóvis A. Ribeiro Valdir Schalch 《Journal of Thermal Analysis and Calorimetry》2009,97(2):529-533
Urban solid residues are constituted of food remaining, grass leaves, fruit peelings, paper, cardboard, rubber, plastic, etc.
The organic fraction formed represents about 50% during the decomposition yields biogas and leachate, which are sources of
pollution. Residue samples were collected from the landfill in different and cells from several ages and the corresponding
leachate, both after treatments, were submitted to thermal analysis. Kinetic parameters were determined using Flynn–Wall–Ozawa
method. The linear relation between the two kinetic parameters (ln A and E) was verified for organic residue urban’s samples, but not for leachate’s sample. The occurred difference can be attributed
to the constituents present in leachate. 相似文献
63.
Pons M Ahufinger V Wunderlich C Sanpera A Braungardt S Sen De A Sen U Lewenstein M 《Physical review letters》2007,98(2):023003
We demonstrate the possibility of realizing a neural network in a chain of trapped ions with induced long range interactions. Such models permit one to store information distributed over the whole system. The storage capacity of such a network, which depends on the phonon spectrum of the system, can be controlled by changing the external trapping potential. We analyze the implementation of error resistant universal quantum information processing in such systems. 相似文献
64.
Alessandra Russo Venera Cardile Adriana C.E. Graziano Carmen Formisano Marisa Canzoneri 《Natural product research》2015,29(17):1630-1640
The objectives of our research were to study the chemical composition and the in vitro anticancer effect of the essential oil of Salvia verbenaca growing in natural sites in comparison with those of cultivated (Sc) plants. The oil from wild (Sw) S. verbenaca presented hexadecanoic acid (23.1%) as the main constituent, while the oil from Sc plants contained high quantities of hexahydrofarnesyl acetone (9.7%), scarce in the natural oil (0.7%). The growth-inhibitory and proapoptotic effects of the essential oils from Sw and Sc S. verbenaca were evaluated in the human melanoma cell line M14, testing cell vitality, cell membrane integrity, genomic DNA fragmentation and caspase-3 activity. Both the essential oils were able to inhibit the growth of the cancer cells examined inducing also apoptotic cell death, but the essential oil from cultivated samples exhibited the major effects. 相似文献
65.
Fraction collection of selected components from a complex mixture plays a critical role in biomedical research, environmental analysis, and biotechnology. Here, we introduce a novel electrophoretic chip device based on a signal processing theorem that allows simultaneous space sampling for fractionation of ssDNA target fragments. Ten parallel extraction channels, which covered 1.5-mm-long sampling ranges, were used to facilitate the capturing of fast-moving fragments. Furthermore, the space sampling extraction made it possible to acquire pure collection, even from partly overlapping fragments that had been insufficiently separated after a short electrophoretic run. Fragments of 180, 181, and 182 bases were simultaneously collected, and then the recovered DNA was PCR amplified and assessed by CE analysis. The 181-base target was shown to be isolated in a 70-mm-long separation length within 10 min, in contrast to the >50 min required for the 300-mm-long separation channel in our previous study. This method provides effective combination of time and space, which is a breakthrough in the traditional concept of fraction collection on a chip. 相似文献
66.
On-chip fraction collection for multiple selected ssDNA fragments using isolated extraction channels
Li Z Sun K Sunayama M Matsuo Y Mizeikis V Araki R Ueno K Abe M Misawa H 《Journal of chromatography. A》2011,1218(7):997-1003
High efficiency and high-purity fraction collection is highly sought in analysis of fragments-of-interest from selective polymerase chain reaction (PCR) products generated by High Coverage Gene Expression Profiling (HiCEP) methods. Here we demonstrate a new electrophoretic chip device enabling automatic high-efficient fractionation of multiple ssDNA target fragments during a run of separation. We used thoroughly isolated extraction channels for each selected target to reduce the risk of cross-contamination between targets due to cross-talk of extraction channels. Fragments of 35, 108 and 138 b, were successfully isolated, then the recovery was PCR-amplified and assessed by capillary electrophoresis (CE) analysis. Total impurity level of the targets due to unwanted fragments of 0.7%, 2% and 6% respectively, was estimated. Difficulties in collecting multiple target factions are due to band diffusion and DNA adsorption to the walls for the fragments in the separation channel, which is generated by transferring the DNA target fraction from the extraction section to the target reservoir. Therefore, we have carefully measured band broadening and analyzed its influence on the separation resolution due to the delay. 相似文献
67.
Two methods are presented that were designed to circumvent the persistent problem of benzofuran formation and instead yield a spiroketal of the rubromycin family type. First, using an alternative disconnection, a hemiketal conjugate addition to a naphthaquinone electrophile was investigated. Synthesis of the requisite electrophile provided insight into the selective oxidation and functionalization of the naphthalene portion. Second, the electronic features of the isocoumarin ring system were adjusted, and the corresponding reactivity further supports the hypothesis that electron-rich isocoumarins are capable of spiroketalization. Robust, flexible syntheses from simple precursors were developed that allowed multiple reduced isocoumarins to be generated. Combined, the data presented herein give insight into the sensitivities of this family and illuminate other potential methods of spiroketalization. In addition, the convergent assembly of substrates containing different naphthaquinone and isocoumarin subunits highlights the utility of our 1,3-dipolar cycloaddition approach to generate analogs of these structures for SAR, as well as chemical reactivity studies. 相似文献
68.
Corzana F Busto JH Marcelo F de Luis MG Asensio JL Martín-Santamaría S Sáenz Y Torres C Jiménez-Barbero J Avenoza A Peregrina JM 《Chemical communications (Cambridge, England)》2011,47(18):5319-5321
A novel Tn antigen mimic, in which the natural underlying amino acid has been replaced by the non-natural α-methylserine analogue, is reported. This derivative exhibits a similar affinity for a natural lectin as for the natural Tn and retains the bioactive conformation observed in the Tn-containing glycopeptides with anti-MUC1 antibodies. 相似文献
69.
Masubuchi M Toyota T Yamada M Seki M 《Chemical communications (Cambridge, England)》2011,47(29):8433-8435
Molecular self-assemblies exhibiting automatic motions have received much attention as potential artificial models of living organisms. We have developed a microfluidic picolitre nozzle-array device to form multilamellar lipid tubes (MLTs) under fluidic shear stress, which transformed into different two patterns (yarn-balls and double-helixes) and also exhibited unique self-actuation behaviors. 相似文献
70.
Monreal MJ Khan SI Kiplinger JL Diaconescu PL 《Chemical communications (Cambridge, England)》2011,47(32):9119-9121
A new inverted sandwich of a μ-η(6),η(6)-toluene diuranium complex reacted with quinoxaline to form a tetranuclear macrocycle with ferrocene diamide uranium(IV) vertices and reduced quinoxaline edges. 相似文献