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91.
Angel Mulero María I. Parra Francisco L. Román Santiago Velasco 《The Journal of chemical thermodynamics》2010,42(7):938-946
In this work, we use a general expression to accurately correlate the liquid density, the vaporization enthalpy, the surface tension, and the isobaric heat capacity of a saturated liquid versus temperature along the whole coexistence curve. The general expression used is the same for the four thermodynamic properties, and uses both critical and triple point values as reference. As representative examples of the use of the model, results are given for a set of 22 pure substances. We find that this general expression correlates the data with smaller or similar overall deviations when compared with other published models whose number of coefficients are the same or greater. 相似文献
92.
在低温条件下采用定向刻蚀技术, 对金属Ti片表面用H2O2溶液进行刻蚀氧化, 制备了垂直生长的纳米TiO2叶片状阵列薄膜电极. 通过X射线衍射分析表明, 纳米TiO2叶片状阵列薄膜经500 ℃下烧结1 h后, 从无定型转变为锐钛矿相. 场发射扫描电子显微镜观察表明: 在80 ℃下的H2O2溶液刻蚀氧化, 经1 d制备得到的是Ti片表面垂直生长的叶片状阵列, 其形貌均匀且完整地
关键词:
2')" href="#">纳米TiO2
叶片状阵列电极
染料敏化太阳电池
电子传输 相似文献
93.
Ademir Aparecido Constantino Dario Landa-Silva Everton Luiz de Melo Candido Ferreira Xavier de Mendonça Douglas Baroni Rizzato Wesley Romão 《Annals of Operations Research》2014,218(1):165-183
This paper tackles a Nurse Scheduling Problem which consists of generating work schedules for a set of nurses while considering their shift preferences and other requirements. The objective is to maximize the satisfaction of nurses’ preferences and minimize the violation of soft constraints. This paper presents a new deterministic heuristic algorithm, called MAPA (multi-assignment problem-based algorithm), which is based on successive resolutions of the assignment problem. The algorithm has two phases: a constructive phase and an improvement phase. The constructive phase builds a full schedule by solving successive assignment problems, one for each day in the planning period. The improvement phase uses a couple of procedures that re-solve assignment problems to produce a better schedule. Given the deterministic nature of this algorithm, the same schedule is obtained each time that the algorithm is applied to the same problem instance. The performance of MAPA is benchmarked against published results for almost 250,000 instances from the NSPLib dataset. In most cases, particularly on large instances of the problem, the results produced by MAPA are better when compared to best-known solutions from the literature. The experiments reported here also show that the MAPA algorithm finds more feasible solutions compared with other algorithms in the literature, which suggest that this proposed approach is effective and robust. 相似文献
94.
Alfonso Miranda-Molina Agustín López-Munguía María Luisa San Román Jaime Escalante Marco Antonio Leyva Ana María Puebla Edmundo Castillo Laura Álvarez 《Tetrahedron: Asymmetry》2010,21(1):43-50
The monoglucosyl-inositols α-d-glucopyranosyl-(1→4)-4d-myo-inositol 3 and α-d-glucopyranosyl-(1→1)-1d-myo-inositol 4 were synthesized by a combined enzymatic transglucosylation and hydrolysis strategy, using cyclodextrin glucosyl transferase (CGTase) from Thermoanaerobacter sp., followed by hydrolysis with Aspergillus niger glucoamylase. The glucosides were separated by preparative HPLC and fully characterized by extensive 1D and 2D NMR studies. The structure of the regioisomer 4 was confirmed by X-ray crystallography of its perbenzoylated derivative 4a. Both isomers demonstrated in vivo anti-inflammatory activity at comparative levels to corticosterone on mouse ear oedema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) and in rat hind paw oedema induced by carrageenan. 相似文献
95.
Renato M. Fonseca Jorge C. Rom?o Ana M. Teixeira 《The European Physical Journal C - Particles and Fields》2012,72(11):1-16
We present a generator for single top-quark production via flavour-changing neutral currents. The MEtop event generator allows for Next-to-Leading-Order direct top production pp??t and Leading-Order production of several other single top processes. A?few packages with definite sets of dimension six operators are available. We discuss how to improve the bounds on the effective operators and how well new physics can be probed with each set of independent dimension six operators. 相似文献
96.
E.A. Zaragoza-Contreras E.D. Lozano-Rodríguez M. Román-Aguirre W. Antunez-Flores C.A. Hernández-Escobar Sergio G. Flores-Gallardo A. Aguilar-Elguezabal 《Micron (Oxford, England : 1993)》2009,40(5-6):621-627
The synthesis of multi-walled carbon nanotube/polystyrene composites, with nanotube concentrations of 0.04, 0.08 and 0.16 wt%, was carried out by in situ bulk-suspension polymerization with the assistance of sonication. By using this method both encapsulation and exfoliation of the nanotubes into the polymer host were achieved. Evidence of significant nanotube fragmentation was found by scanning electron microscopy; the cause of such fragmentation was attributed to the induction of strong cavitation due to the application of ultrasound during the synthesis. Infrared spectroscopy showed no evidence of the formation of covalent bonds between the nanotubes and the polystyrene during the process of synthesis. The thermal stability was not improved by the inclusion of the nanotubes, it was attributed to the low nanotube concentrations; however, composites glass transition temperature showed improvements. 相似文献
97.
Effect of added NaCl on the spectral and kinetic properties of cationically charged dye (cresyl violet) and anionically charged
surfactant (sodium dodecyl sulphate) were studied in the pre-micellar and micellar regions. Addition of 0.2 M NaCl to dye-surfactant
solution decreased the critical micellar concentration for the micellization of the dye in sodium dodecyl sulphate to 1.2
× 10−3 M. Time-resolved studies using a stopped-flow spectrometer showed that NaCl influences the dynamics of micellisation. Addition
of NaCl during the dye-surfactant complex formation converted the complex into micellized form at NaCl concentration of 0.01
to 0.05 M. In contrast, much higher concentration of NaCl (2 M) is required for the salting-out effect of the dye-surfactant
complex for conversion to the micellized form 相似文献
98.
H. Hirata H. Komatsubara W. Blumund H. S. Rawdon R. Glockerund E. Kaupp F. Foerster G. L. Clark P. K. Frölich A. H. W. Aten L. M. Boerlage V. Kohlschütter A. Good F. Jakober D. J. Brown J. Heyrovsky F. S. Aumonier H. J. S. Sand J. E. Hackford H. S. Lukens A. Schleicher L. Toussaint A. Lassieur S. Wiechowski H. Rom A. Jilek J. Lukas Erich Müller R. Belasio E. Mellana P. Drossbach H. Ginsberg R. Geith 《Analytical and bioanalytical chemistry》1928,75(6):244-255
99.
Cécile Machut-Binkowski Frédéric Hapiot Roméo Cecchelli Patrick Martin Eric Monflier 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):567-572
For many commercial drugs, reaching the central nervous system in large amount without damaging the blood-brain-barrier (BBB)
remains a challenging task. We present here a supramolecular strategy aiming at using a well-defined cyclodextrin-coated liposomes
as drug carrier and adamantoyl saccharides as BBB-interacting ligands. In this study, the liposome is constituted of n-alkyldimethylammoniumcyclodextrins incorporated in the lipid bilayer of a 3/7 cholesterol/dipalmitoylphosphatidylcholine
mixture and the ligand is constituted of an adamantoylglucose molecule whose adamantoyl moiety can be included in the CD cavity.
The whole supramolecular assembly has been characterized by light-scattering and 31P NMR measurements. Toxicity and permeability studies on an in vitro model of the BBB clearly demonstrated a 5-fold improved
ability of the modified liposome to enter the BBB-endothelial cells compared to the non-coated liposome. Fluorescence labelling
of these liposomes is also displayed with DiI as a fluorescent probe. 相似文献
100.
Hari M. Gupta José R. Campanha Daniela R. de Aguiar Gabriel A. Queiroz Charu G. Raheja 《Physica A》2007
We study the statistical distribution of firm size for USA and Brazilian publicly traded firms through the Zipf plot technique. Sale size is used to measure firm size. The Brazilian firm size distribution is given by a log-normal distribution without any adjustable parameter. However, we also need to consider different parameters of log-normal distribution for the largest firms in the distribution, which are mostly foreign firms. The log-normal distribution has to be gradually truncated after a certain critical value for USA firms. Therefore, the original hypothesis of proportional effect proposed by Gibrat is valid with some modification for very large firms. We also consider the possible mechanisms behind this distribution. 相似文献