[en] Emission levels for PAHs varied with the type of wood burned. - Four kinds of woods used for residential heating in Australia were selected and burned under two burning conditions in a domestic wood heater installed in a laboratory. The selected wood species included pine (Pinus radiata), red gum (Eucalyptus camaldulensis), sugar gum (Eucalyptus cladocalyx) and yellow box (Eucalyptus melliodora). The two different burning conditions represented fast burning and slow burning, with the air inlet of the combustion chamber respectively 'full open' and 'half open'. By sampling and analysing particulate and gaseous emissions from the burning of each load of wood under defined experimental conditions, PAHs emissions and their profiles in the particulate and gaseous phases were obtained. 16 species out of the 18 selected PAHs were detected. Of these, seven species were detected in the gaseous phase and most were lower molecular weight compounds. Similarly, more than 10 species of PAHs were detected in the particulate phase and these were mostly heavier molecular weight compounds. Under both burning conditions, emission levels for total PAHs and total genotoxic PAHs were the highest for pine and lowest for sugar gum, with red gum being the second highest, followed by yellow box. Using the specific sampling method, gaseous PAHs accounted for above 90% mass fraction of total PAHs in comparison to particulate PAHs (10%). The majority of the genotoxic PAHs were present in the particulate phase. PAHs emission levels in slow burning conditions were generally higher than those in fast burning conditions

[en] The skeleton assembly platform is the key equipment for the manufacture of nuclear fuel assembly. At present, there is no calibration method related to the skeleton assembly platform at home or abroad. In order to ensure the accurate positioning of the frame and the dimension of the skeleton quality, the calibration method of the skeleton assembly platform is carried out. Calibration methods include calibration items, calibration required standard instruments, calibration methods and feasibility analysis of straightness instead of flatness and so on. After the calibration method is determined, the calibration experiment is carried out according to the calibration method. The calibration results are in accordance with the technical requirements, the evaluation uncertainty is also made to prove the calibration method is workable, and it can be extended to assembly platform, pull rods platform and expansion platform, etc. (authors)

[en] The electron gun was developed and will be used on the Cockcroft-Walton accelerator for electron irradiation processing. The structure, size and operation parameters were optimized by electron beam test. The results show that its main performance data are electron beam 5-20 keV/60-100 mA, beam spot φ15-30 mm, half diverge angle 0.6 degree -1.6 degree, instability ±0.6%,and the life time more than 5 000 h. (authors)

[en] Diffusional kurtosis imaging (DKI) is a recent developed novel diffusion-weighted magnetic resonance imaging. Different from diffusion weighed imaging and diffusion tensor imaging (DTI), DKI can quantify the degree of water diffusion departure from a Gaussian form to delineate microstructure in tissue, so that it can reflect physiological and pathological conditions. Recently, DKI have been widely used in assessment of central nervous system, especially in brain tumors. In this article we aimed to summarize the principles of DKI and its application in brain tumors. (authors)

[en] A supported liquid membrane with ionic liquid was used for the separation of toluene/cyclohexane. The interactions of ionic liquid with toluene and cyclohexane were calculated and experimentally studied by quantum chemical calculation and liquid-liquid extraction process. The results showed [BPy][BF_4] have stronger interaction with toluene than that with cyclohexane. The selectivity of SILM processes was larger than 10 at the temperature of 323 K and the flow rate of 13.5 mL·min"-"1 on both shell side and lumen side. Due to the higher viscosity of IL, SILM process had good long-term stability. As the effects of mass transfer driving force of SILM process, the flux and removal efficiency increased with increase of initial toluene concentration, while the selectivity decreased because of the competitive transport. Base on the resistance in-series model and experimental results, the mass transfer resistance was mainly lay liquid membrane phase. The influence of flow rates on both sides was slight. The higher temperature could enhance the mass transfer performance significantly. The removal efficiency increased from 28.2% to 45.1% with the increasing of operation temperature from 298 K to 323 K

[en] This paper is concerned with the problem of robust H_∞ control for structured uncertain stochastic neural networks with both discrete and distributed time varying delays. A sufficient condition is presented for the existence of H_∞ control based on the Lyapunov stability theory. The stability criterion is described in terms of linear matrix inequalities (LMIs), which can be easily checked in practice. An example is provided to demonstrate the effectiveness of the proposed result

[en] Objective: To study the effects of the strength and number of b values on ADC measurements of normal brain. Methods: Seven different diffusion weightings were applied in twenty normal adult brains in diffusion tensor imaging. the brain ADC maps were calculated using seven different combinations of b values based on strength (b₀b₁, b₀b₂, b₀b₃, b₀b₄, b₀b₅) and on numbers (b₀b₆. b₀b₆, b₀b₁b₆, b₀b₁b₂b₆, b₀b₁b₂b₃b₆, b₀b₁b₂b₃b₄b₆ and b₀b₁b₂b₃b₄b₅b₆). The average of the ADC was measured and compared at the caudate nucleus, posterior limb of the internal capsule, thalamus, centrum semiovale, genu of corpus callosum and splenium of corpus callosum. Results: The measured ADC was significantly decreased accompanied with increase of b values (P<0.05), but did not correlated with the b values number (P>0.05). Conclusion: The strength of b values, not numbers of b value influences measurement of ADC, which should be considered in clinical study

[en] Objective: To explore the imaging diagnosis of chorea associated with nonketotic hyperglycemia by describing its CT and MR findings and correlating those findings with the clinical manifestations. Methods: The imaging findings and clinical data from 6 patients with chorea associated with nonketotic hyperglycemia were retrospectively analyzed. All 6 patients had unenhanced CT scans, 1 also had MR imaging examination. Three of 6 patients had follow-up CT scans and 1 of 3 patients had follow-up MR imaging studies. Results: CT studies of all 6 patients showed unilateral or bilateral hyperdense striatum. The putamen was involved in all 6 patients, the caudate nucleus or lateral portion of the globus pallidus were involved in 5 of all 6 patients. All 3 follow-up CT studies depicted a decreased or resolved hyperdensity of the abnormal striatum. T₁-weighted MR images in 1 patient showed the hyperintense lesions of bilateral lentiform nuclei, T₂-weighted MR images of the patient showed the hypointense lesions of the corresponding lentiform nuclei, and its follow-up MR images depicted invariable signal intensity of T₁-weighted and T₂-weighted images. In all patients, the chorea resolved within 2 to 6 days after treatment of the hyperglycemia. Conclusion: The characteristic imaging findings of chorea associated with nonketotic hyperglycemia can suggest an accurate diagnosis. (authors)

[en] Objective: To evaluate the relationship between Multi-slices spiral (MSCT) perfusion and micro vessel density (MVD) in maxillofacial tumors. Methods: Thirty-one cases of maxillofacial tumors were studied with MSCT perfusion imaging before operation. The time-density curve, perfusion, time to peak (TTP), and Peak enhancement imaging (PEI) of tumors were calculated. MVD of the tumors was measured with immuno-histochemical method by means of detecting factor VIII in all the histologic specimens. Relativity analysis was carried between MSCT perfusion imaging parameters, perfusion curve types and MVD. Results: MVD of maxillofacial tumors were higher than normal tissue. MVD remarkably correlated with malignancy of the tumors. Perfusion and time to peak (TTP) correlated well with MVD (t=7.09, 4.10, P<0.05), but peak enhancement imaging (PEI) did not (t=0.76, P>0.05). Significant difference of MVD in three types of perfusion curve was found (F=8.09, P<0.05). The tumors in the rapid ascend style had the highest MVD. Conclusion: There are close correlations between MVD and perfusion, time to peak (TTP) and the shape of perfusion curve. MSCT perfusion imaging might evaluate MVD of maxillofacial tumors. It is a useful method in estimating the degree of angiogenesis and prognosis of maxillofacial tumors.(authors)

[en] The author described the dynamic characteristics simulation of pressurizer control system by PC using the Simulink simulated software of MATLAB and got the well results