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排序方式: 共有458条查询结果,搜索用时 15 毫秒
31.
New thermosensitive polysaccharide (P-g-pNIPAAm) was synthesized by graft-polymerization of p(N-isopropylacrylamide) (pNIPAAm) onto pullulan (P) using Ce(IV) ion as initiator. The grafted polysaccharide was characterized by FT-IR and 1H NMR spectroscopy and elemental analysis. Its flocculation efficiency was studied in a clay suspension, in comparison with p(NIPAAm) homopolymer, as a function of the polymer dose, temperature and settling time. The thermosensitive polysaccharide could induce clay particle flocculation both below and above the lower critical solution temperature (LCST), but the process was more effective above the LCST. A lower value of the residual turbidity at the optimum polymer dose and a wider flocculation window were recorded at temperature above the LCST. The floc size distribution and surface morphology revealed bigger size flocs when the flocculation was performed above the LCST. The re-dispersion effect was negligible for the flocs obtained in the presence of P-g-pNIPAAm. 相似文献
32.
Constantin Sârbu Andréas Johansson Neeraj Suri Nachiappan Nagappan 《Empirical Software Engineering》2010,15(4):380-422
As the complexity of modern Operating Systems (OS) increases, testing key OS components such as device drivers (DD) becomes increasingly complex given the multitude of possible DD interactions. Currently, DD testing entails a broad spectrum of techniques, where static (requiring source code) and dynamic (requiring the executable image) and static-dynamic testing combinations are employed. Despite the sustained and improving test efforts in the field of driver development, DDs still represent a significant cause of system outages as the coverage is invariably limited by test resources and release time considerations. The basic factor is the inability to exhaustively assess and then cover the operational states, leading to releases of inadequately tested DDs. Consequently, if representative operational activity profiles of DDs within an OS could be obtained, these could significantly improve the understanding of the actual operational DD state space and help focus the test efforts. Focusing on characterizing DD operational activities while assuming no access to source code, this paper proposes a quantitative technique for profiling the runtime behavior of DDs using a set of occurrence and temporal metrics obtained via I/O traffic characterization. Such profiles are used to improve test adequacy against real-world workloads by enabling similarity quantification across them. The profiles also reveal execution hotspots in terms of DD functionalities activated in the field, thus allowing for dedicated test campaigns. A case study on actual Windows XP and Vista drivers using various performance and stability benchmarks as workloads substantiates our proposed approach. 相似文献
33.
34.
Denis Prodius Fliur Macaev Valeriu Mereacre Sergiu Shova Yurii Lutsenco Eugenia Styngach Patricia Ruiz Dmitry Muraviev Janusz Lipkowski Yurii A. Simonov Constantin Turta 《Inorganic chemistry communications》2009,12(7):642-645
The novel μ3-oxo-bridged heterotrinuclear iron(III)-copper(II) trichloroacetates of the composition [Fe2CuO(CCl3COO)6(THF)3] (1a) and [Fe2CuO(CCl3COO)6(4-DMAP)3] (1b) have been synthesized and characterized by X-ray crystallography, IR and Mossbauer spectroscopy. These clusters were used as precursors for the synthesis of the nanosized catalytic system (~5–6 nm of γ-Fe2O3/CuO), which works as an efficient organic phase catalyst (~0.02 mol%) in a one-pot three component Biginelli synthesis. 相似文献
35.
Bogdan Bucur Gabriel Lucian Radu Constantin Nicolae Toader 《European Food Research and Technology》2008,226(6):1335-1342
A portable bienzymatic analytical system was developed for the chronoamperometric analysis of methanol–ethanol mixtures. The
system consists of two biosensors, one based on alcohol dehydrogenase (ADH) that responds only to the ethanol and the second
one based on alcohol oxidase (AOX) that responds to both methanol and ethanol. The transducers were screen-printed electrodes
(SPEs) modified with mediators: Meldola blue for ADH and Co-phthalocyanine for AOX. The calibration graph of the ADH biosensor
is linear between 0.3 and 8 mmol/L ethanol. The AOX biosensor is able to quantify both analytes in mixtures that contain methanol
between 3 and 70 mmol/L and ethanol ranging from 15 to 110 mmol/L. Interferences due to non-specific oxidations from common
oxidizable compounds like gallic acid and ascorbic acid were smaller in the case of transducer based on Meldola blue. The
analytical system was successfully tested on real samples: non-alcoholised beer (NAB) spiked with ethanol or methanol and
a falsified rose wine (FRW). 相似文献
36.
Journal of Logic, Language and Information - One lists the distinct pairs of categorical premises (PCPs) formulable via only the positive terms, S,P,M, by constructing a six by six matrix obtained... 相似文献
37.
Scientometrics - Although citations are used as a quantifiable, objective metric of academic influence, references could be added to a paper solely to inflate the perceived influence of a body of... 相似文献
38.
Constantin Mihai Gabriel Ştefan Liviu-Daniel Ionescu Bogdan Duong Ngoc Q. K. Demarty Claire-Héléne Sjöberg Mats 《International Journal of Computer Vision》2021,129(5):1526-1550
International Journal of Computer Vision - In this paper, we report on the creation of a publicly available, common evaluation framework for image and video visual interestingness prediction. We... 相似文献
39.
Sergiu Cecoltan Izabela-Cristina Stancu Diana Maria Drăguşin Andrada Serafim Adriana Lungu Cătălin Ţucureanu Iuliana Caraş Vlad Constantin Tofan Aurora Sălăgeanu Eugeniu Vasile Romain Mallet Daniel Chappard Cristin Coman Mircea Istodorescu Horia Iovu 《Journal of materials science. Materials in medicine》2017,28(10):153