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11.
A basic result concerning LTL, the propositional temporal logic of linear time, is that it is expressively complete; it is equal in expressive power to the first order theory of sequences. We present here a smooth extension of this result to the class of partial orders known as Mazurkiewicz traces. These partial orders arise in a variety of contexts in concurrency theory and they provide the conceptual basis for many of the partial order reduction methods that have been developed in connection with LTL-specifications.We show that LTrL, our linear time temporal logic, is equal in expressive power to the first order theory of traces when interpreted over (finite and) infinite traces. This result fills a prominent gap in the existing logical theory of infinite traces. LTrL also constitutes a characterisation of the so-called trace consistent (robust) LTL-specifications. These are specifications expressed as LTL formulas that do not distinguish between different linearisations of the same trace and hence are amenable to partial order reduction methods. 相似文献
12.
Pseudomonas sp. and Pseudomonas putida can utilize dinitrotoluene (DNT) as N-source after the enzymatic removal of nitro groups from the aromatic ring. Addition of nutrients is known to stimulate the biodegradation process. Poultry litter has consortia of microorganisms (including Pseudomonas) along with many nutrients. The objective of this research was to study the biodegradation of 2,4- and 2,6-DNT contaminated soil (from Badger Army Ammunition Plant) using poultry litter. Complete biodegradation of both 2,4- and 2,6-DNT in the soil was observed after 1-day interaction with poultry litter. No degradation was observed using autoclaved litter. 相似文献
13.
14.
Tsung-Hsuan?Tsai Soundappan?Thiagarajan Shen-Ming?ChenEmail author 《Journal of Applied Electrochemistry》2010,40(12):2071-2076
Simple and eco-friendly electro deposition method was employed for the fabrication of Au–Ag bimetallic nanoparticles modified
glassy carbon electrode. Nano Au–Ag film modified glassy carbon electrode surface morphology has been examined using atomic
force microscopy. Electrodeposited Au–Ag bimetallic nanoparticles were found in the average size range of 15–50 nm. The electrochemical
investigations of nano Au–Ag/1-butyl-3-methylimidazolium tetrafluoroborate-nafion film have been carried out using cyclic
voltammetry and electrochemical impedance spectroscopy. The nano Au–Ag/1-butyl-3-methylimidazolium tetrafluoroborate-nafion
film modified glassy carbon electrode holds the good electrochemical behavior and stability in pH 7.0 phosphate buffer solutions.
The nano Au–Ag/1-butyl-3-methylimidazolium tetrafluoroborate-nafion modified glassy carbon electrode was successfully employed
for the detection of H2O2 in the linear range of 1–250 μM in lab samples, and 1 × 10−3–2 × 10−2 M in real samples, respectively. 相似文献
15.
The effect of sesame lignans on the thermal and storage stability of edible vegetable oils (soybean-SBO, sunflower-SFO and ricebran-RBO) was studied by (i) determining the total free radical scavenging activity (RSA) using DPPH, (ii) % total tocol retention, (iii) lignan profile and (iv) PUFA composition. The order of RSA and retention of total tocols of oils heated up to 120 min at frying temperature (FT) were RBO = SBO > SFO and RBO > SBO > SFO, respectively. Heating SBO or SFO at FT after addition of 1.2% lignans increased RSA of SBO to a greater extent than that of SFO, and increased retention of total tocols only in SBO. However, addition of lignans did not further increase the RSA of RBO. Heating oils with added lignans, increased sesamol and decreased sesamolin while sesamin was relatively resistant to heat. These findings suggest that sesame lignans may have potential application as natural antioxidants in the edible oil and food industry. 相似文献
16.
We identify a subclass of timed automata called product interval automata and develop its theory. These automata consist of
a network of timed agents with the key restriction being that there is just one clock for each agent and the way the clocks
are read and reset is determined by the distribution of shared actions across the agents. We show that the resulting automata
admit a clean theory in both logical and language theoretic terms. We also show that product interval automata are expressive
enough to model the timed behaviour of asynchronous digital circuits. 相似文献
17.
BACKGROUND: The procoagulant effect of anionic phospholipid may play a major role in the development of arterial thrombosis. METHODS AND RESULTS: Annexin V, a calcium-dependent anionic-phospholipid-binding protein, was expressed and isolated from Escherichia coli and its antithrombotic effect examined in a rabbit carotid artery thrombosis model. A partially occlusive thrombus was formed in the left carotid artery by application of electric current to produce an approximately 50% occlusion of the lumen. After the current was discontinued, flow ceased completely within 42+/-12 minutes (n=6) because of continuing platelet/fibrin thrombus formation. When annexin V was given at doses of 2.8 to 16.6 microg x kg(-1) x min(-1) for a period of 180 minutes, starting at the time the current was stopped, there was a dose-dependent inhibition of thrombus formation. At a dose of 5.6 microg x kg(-1) x min(-1), blood flow remained patent throughout the infusion and for an additional 60 minutes after the infusion was stopped. In addition, there was a decrease in thrombus weight (16+/-7.4 versus 2.0+/-1.0 g), (125)I-fibrin deposition (approximately 45% reduction, P<.001), and (111)In-labeled platelet accumulation (approximately 43% reduction, P<.001). Prior mixing of annexin V with phosphatidylserine micelles abolished the antithrombotic effect of annexin V, whereas mixing with phosphatidylcholine micelles had no effect. The antithrombotic effect of annexin V was not associated with bleeding tendency, as judged by the amount of blood absorbed in a gauze pad placed in a surgical incision extending to the muscle tissue and by the standard template bleeding time. CONCLUSIONS: These observations support a potentially important role for anionic phospholipid exposure in platelets in arterial thrombosis, and inhibition of this activity could be a novel target for therapy in coronary thrombosis and stroke and after angioplasty. 相似文献
18.
Study of liquid sloshing: numerical and experimental approach 总被引:1,自引:0,他引:1
In this paper, sloshing phenomenon in a rectangular tank under a sway excitation is studied numerically and experimentally.
Although considerable advances have occurred in the development of numerical and experimental techniques for studying liquid
sloshing, discrepancies exist between these techniques, particularly in predicting time history of impact pressure. The aim
of this paper is to study the sloshing phenomenon experimentally and numerically using the Smoothed Particle Hydrodynamics
method. The algorithm is enhanced for accurately calculating impact load in sloshing flow. Experiments were conducted on a
1:30 scaled two-dimensional tank, undergoing translational motion along its longitudinal axis. Two different sloshing flows
corresponding to the ratio of exciting frequency to natural frequency were studied. The numerical and experimental results
are compared for both global and local parameters and show very good agreement. 相似文献
19.
Osteoid osteoma is an uncommon tumour in the very young. We present a case of osteoid osteoma in a three-year-old boy, who was treated as a case of sclerosing osteomyelitis of the femur. Because of persistent pain and lack of response to treatment, further radiological investigation confirmed the diagnosis to be that of an osteoid osteoma. 相似文献
20.
L. M. Woods P. Silvestre P. Thiagarajan G. A. Patrizi G. Y. Robinson K. M. Jones M. Al-Jassim 《Journal of Electronic Materials》1994,23(11):1229-1233
Quantum well (QW) structures consisting of InGaAsP wells and InGaAsP barriers grown by gas-source molecular beam epitaxy have
been examined by low temperature photoluminescence (PL) in order to evaluate the contributions of compositional fluctuations
in the quaternary alloy and of interface roughness to the PL linewidth. The well material was InGaAsP with a bandgap corresponding
to a wavelength of 1.3 μm and the barrier material was InGaAsP of 1.15 μm. The theory for QW excitonic linewidths as a function
of well thickness Lz due to fluctuations in alloy composition has been extended to include the case of the quaternary InGaAsP barrier. If the
interfaces are atomically abrupt, the linewidth is dominated by compositional fluctuations in the well at large Lz and compositional fluctuations in the barrier at small Lz. The theory predicts a weak dependence of the linewidth on Lz since the composition of the well and barrier are similar. For rough heterointerfaces, the theory indicates the usual increase
in linewidth with decreasing Lz. Photoluminescence measurements at 13K in arrays of single InGaAsP/InGaAsP QWs with Lz from 1.0 to 6.0 nm show only a weak variation of the full width at half maximum (FWHM) with Lz, in agreement with the theory for smooth interfaces. Furthermore, the lowest measured FWHM of 8.9 meV was found for a narrow
well of Lz=1.8 nm, indicating the InGaAsP/InGaAsP interfaces are smooth and that the PL linewidth is dominated by compositional fluctuations. 相似文献