微型降膜燃烧器燃烧试验研究

本文利用水平螺旋槽降膜蒸发机理自行设计了降膜蒸发器,应用在微型燃烧器中,能够实现液体燃料的快速均匀蒸发。在没有动力的情况下实现了液态燃料的气化,而且这种燃烧器燃烧效率高,排放的污染物远低于国家标准,在同类产品中性能领先,对我国微型燃烧器的全新雾化燃烧方式的研究开发具有重要的促进意义。     

Numerical assessment of the analytical models used to determine flexural and shear moduli in I-Beams when the tensile and compressive moduli are different

The different compressive and tensile moduli of fibre reinforced composites have been considered in the analysis of the flexural and shear moduli of I-beams. Firstly, the neutral axis has been determined analytically and then, assuming that location of the neutral axis, the analytical flexural modulus of I-beams has also been obtained. In order to assess the proposed procedure, virtual pure bending and three-point bending tests at different spans have been carried out using the finite element method. The compressive and tensile moduli have been taken into account by defining two parts in the numerical models. The numerical flexural and shear moduli have been determined by reducing the data obtained in the virtual tests. Analytical and numerical results are in good agreement. Therefore, the flexural modulus determined by the proposed analytical approach can be introduced as a material property in the finite element method.     

Evaluation of heavy metal bioavailability in soil amended with poultry manure using single and BCR sequential extractions

In the present study, three-step Community Bureau of Reference sequential extraction scheme (BCR-SES) and single extraction methods were performed to assess the mobility and availability of heavy metals (Cd, Cu, Pb, Fe and Zn) in an agricultural soil before and after amendment with poultry waste (PW).The PW samples were collected from poultry farms, situated in Hyderabad Sindh, Pakistan. The extractable heavy metals were measured by flame and electrothermal atomic absorption spectrometry. The validation of the method was carried out by analysis of a certified reference material of soil amended with sewage sludge (BCR-483). The single extractions using calcium chloride and EDTA, separately, while BCR-SESs were developed to evaluate the available heavy metals to plants and their environmental accessibility for control soil (CS), PW and soil amended with PW (SPW).The pH of the PW and SPW were found to be < 6.0, which may enhance the leaching of heavy metals to agricultural soil. The results from the partitioning study indicated that easily mobilised forms (acid exchangeable) of Cd were higher than other heavy metals. The oxidisable fractions of all heavy metals were dominant in PW and SPW as compared to found in CS samples. The EDTA- and CaCl₂-extractable heavy metals correspond to 5.0 to 10 and 0.5 to 3.0%, respectively of total contents in all three solid samples. Contamination factors revealed that the retention of Pb and Zn were higher compared with Cu, Cd and Fe in CS, PW and SPW samples.     

Study of toxicity of imidazolium ionic liquids to watercress (<Emphasis Type="Italic">Lepidium sativum</Emphasis> L.)

The sensitivity of Lepidium sativum L. germination to three imidazolium ionic liquids was investigated in solutions and soils artificially contaminated with mixtures of those compounds. In case of aquatic solutions, the toxic character of analyzed compounds is connected with their hydrophobicity. The seedling growth is increasing with the decrease in ionic liquid hydrophobicity. The novelty of those studies is the application of high-performance liquid chromatography, which was used for the determination of ionic liquid quantity absorbed by cress. There was almost linear relationship between decrease in root germination and amount of ionic liquid uptaken by cress. Furthermore, the systematic studies on the influence of total organic carbon content in soil on the toxicity of ionic liquids to cress were performed for the first time. Hazardous effects appeared to be closely connected with organic matter: with the decrease of total organic carbon quantity, the inhibition of plant growth was more significant. Visual effects of ionic liquid toxic activity to garden cress are similar as in the case of nutrient deficit in plants. Figure Visual phytotoxicity effects observed during the test; leaf chromatosis: light green and yellow (up photos), violet (lower photos)     

Temperature and variable strain rate sensitivity in recycled HDPE

The recycling of post-consumer plastics and their utilization as raw materials to develop value-added products has become an important goal worldwide. The present work is concerned with the thermo-mechanical analysis of recycled high-density polyethylene (HDPE) under uniaxial tensile loading. The main focus is to propose a one-dimensional phenomenological model able to describe the influence of temperature and strain rate on the mechanical behavior. Tensile tests were performed over a wide range of temperatures (from 25°C to 100°C). Each experiment was performed under controlled strain rate varying from 7.25 × 10⁻⁵ s⁻¹ to 7.25 × 10⁻³ s⁻¹ in steps. It is shown that only one tensile test performed at three different temperatures is necessary to fully identify experimentally all material parameters that arise in the theory. Thus, with this experimental procedure, the number of tests used to evaluate the mechanical properties of recycled HDPE is significantly reduced. The experiments are compared with the model predictions and show good agreement.     

A statistical degradation model for the service life prediction of aircraft coatings: With a comparison to an existing methodology

An advance on the model used by Guseva et al. [1] for estimating the service life of organic coatings under service conditions from accelerated test results has been developed. Instead of modelling just the times to failure, this new approach uses the complete degradation curve and allows for a more general specification of the failure time distribution. This modified model was then applied to the estimation of the service life (defined as gloss loss) for aircraft coatings and the results were compared to those obtained by Guseva et al. It was found that when this model was applied to the naturally weathered data, gloss loss (and thus failure times at a given level of gloss loss) followed a generalised gamma distribution, rather than the Weibull distribution identified by Guseva et al. Further, the new approach suggested a reduction in the warranty time of about one month. When the model was applied to the accelerated test data, it produced more accurate extrapolations of the median failure time associated with the naturally weathered data - (49.3 months compared to a measured 52 months obtained at the naturally weathered site). In fact, the extrapolated distribution obtained by this new approach was much closer to the distribution for the naturally weathered data than the extrapolated distribution obtained by Guseva et al.     

Proposal to Test a Transient Deviation from Quantum Mechanics’ Predictions for Bell’s Experiment

Quantum mechanics predicts correlations between measurements performed in distant regions of a spatially spread entangled state to be higher than allowed by intuitive concepts of Locality and Realism. These high correlations forbid the use of nonlinear operators of evolution (which would be desirable for several reasons), for they may allow faster-than-light signaling. As a way out of this situation, it has been hypothesized that the high quantum correlations develop only after a time longer than L/c has elapsed (where L is the spread of the entangled state and c is the velocity of light). In shorter times, correlations compatible with Locality and Realism would be observed instead. A simple hidden variables model following this hypothesis is described. It is based on a modified Wheeler–Feynman theory of radiation. This hypothesis has not been disproved by any of the experiments performed to date. A test achievable with accessible means is proposed and described. It involves a pulsed source of entangled states and stroboscopic record of particle detection during the pulses. Data recorded in similar but incomplete optical experiments are analyzed, and found consistent with the proposed model. However, it is not claimed, in any sense, that the hypothesis has been validated. On the contrary, it is stressed that a complete, specific test is absolutely needed.     

Einstein-Podolsky-Rosen Steering for Mixed Entangled Coherent States

By using the Born Markovian master equation, we study the relationship among the Einstein–Podolsky–Rosen (EPR) steering, Bell nonlocality, and quantum entanglement of entangled coherent states (ECSs) under decoherence. We illustrate the dynamical behavior of the three types of correlations for various optical field strength regimes. In general, we find that correlation measurements begin at their maximum and decline over time. We find that quantum steering and nonlocality behave similarly in terms of photon number during dynamics. Furthermore, we discover that ECSs with steerability can violate the Bell inequality, and that not every ECS with Bell nonlocality is steerable. In the current work, without the memory stored in the environment, some of the initial states with maximal values of quantum steering, Bell nonlocality, and entanglement can provide a delayed loss of that value during temporal evolution, which is of interest to the current study.     

The solutions of the strongly nonlocal spatial solitons with several types of nonlocal response functions

The fundamental and second order strongly nonlocal solitons of the nonlocal nonlinear Schr\"{o}dinger equation for several types of nonlocal responses are calculated by Ritz's variational method. For a specific type of nonlocal response, the solutions of the strongly nonlocal solitons with the same beam width but different degrees of nonlocality are identical except for an amplitude factor. For a nonlocal case where the nonlocal response function decays in direct proportion to the $m$th power of the distance near the source point, the power and the phase constant of the strongly nonlocal soliton are in inverse proportion to the $(m+2)$th power of its beam width.