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The multi-inlet condenser has two steam inlets, the main steam inlet of main steam turbine and the steam inlet of auxiliary steam turbine. In this paper, it establishes a two-dimensional model for the multi-inlet condenser. The porous medium concept is used in the simulations. A porosity factor is incorporated into the governing equations to account for the flow volume reduction due to the tube bundles, baffles and other internal obstacles. The mathematical model is based on the fundamental governing conservation equations of mass and momentum, and the air mass fraction conservation equation. Then, the equations are solved by the SIMPLEC algorithm. Research results indicates that : 1) The physical fields, including pressure, velocity, thermal resistances and condensation rate, are obtained by numerical simulation of the multi-inlet condenser. 2) The performance of multi-inlet condenser is better than the performance of single-inlet condenser from the point of view of pressure drop. 3) There is an optimum angle of auxiliary steam inlet to make the minimum pressure drop. The optimum angle of the multi-inlet condenser used in this study is 50.65°.

Aerospace activity in near space (20-50 km) has become a research hotspot for aviation big countries worldwide. Solar radiation study, as the prerequisite to carry out aerospace activity, is facing the barrier of lacking of observation in near space layer. Ozone is the most important factor that affects radiation value in this layer. Based on ECMWF reanalysis data, this input key parameter and its horizontal, vertical and temporal characteristics are analyzedwith results showing obvious regional features in temporal-spatial distribution and varieties. With meteorological data and surface parameters, near space over China is divided into 5 parts. Key factors' value is confirmed over each division. With SBDART radiation transfer model, solar radiation and ultraviolet radiation simulation in near space are conducted separately. Results show that it is influenced by latitude, total ozone and its vertical distribution, radiation varies under complex rules. The average year and monthly solar radiation strengthens changes with latitude reduction, while annual range changes reversely. Air absorbing is related to latitude and land-sea contrast and shows different values and seasonal variations. The ultraviolet radiation over South China Sea reaches its maximum value and minimum annual range, as well as minimum monthly range with value strengthening in summer and weakening in winter. In other areas radiation increases in summer while weakens in winter, monthly range shows double peaks with higher value in spring and autumn, lower in summer and winter. Air absorption in ultraviolet radiation is influenced by multiple factors, vertical varieties over areas besides South China Sea enhance in summer time. The vertical changes of monthly ranges affected by air absorption show consistence in higher and lower layer in June and July, while in other months ranges are bigger in higher layer.

Different deaerators have different structures, and the intensities of deaerating are different. But the deaerator models without considering the structure couldn’t show these aspects. In order to ensure the accuracy of simulation results, concrete structure of the deaerator should be taken into consideration. This paper carried out a mathematical model of horizontal type deaerator with constant nozzles and trays in nuclear power plants. It was built based on the structure of the segmentation deaerators and the process of heat transferring. This paper calculated the vapors condensation rate, it was based on heat transfer coefficient of direct contact condensation, and the heat transfer area of water film when working conditions were corresponding to the empirical formulas. While the working conditions were beyond the limits of empirical formulas, this paper would build models by conservation of energy, so the model could work under any working conditions. These models were installed in the simulation system of Qinshan Phase II., and were tested under variable power and accidental conditions. The testing results show that the models could fit for different steady working conditions. Compared with the outputs and the actual operating data, the error was small. Under the conditions of variable power and turbine tripping, changing of the parameters have the same trend curve with the actual operating data. Because of taking the concrete structure into consideration, these models can be performed better of the specific characteristics of the horizontal type deaerators with constant nozzles and trays in nuclear power plants, therefore the results are more accurate than the models without considering the structure.

To access the pathological changes of the functional localization of the primary auditory cortex in auditory neuropathy patients using magnetoencephalography (MEG).The M100 waves of cortical evoked magnetic fields (AEF) evoked by 0.5, 1, 2, 4, 6, 8 kHz pure tones were measured respectively in 10 auditory neuropathy patients (20 ears) and 15 healthy young subjects (30 ears) using a whole head 306 channel magnetoencephalography (MEG) system. The auditory cortex magnetic source imaging obtained by superimposing functional MEG data on structural magnetic resonance image (MRI).The M100 sources were obtained in all 15 healthy young subjects in all frequency except for 8 kHz in 16 ears. But in auditory neuropathy patients, the ratio of M100 from 0.5 to 6 kHz were 27.5% (11/40), 22.5% (9/40), 7.5% (3/40), 5% (2/40), 5% (2/40) respectively and no any waves in 8 kHz. The evoked ratio of M100 in low frequency was high and that decreased gradually with increasing of evoked pure tone frequency. The M100 latentencies and amplitudes were longer and lower in patient group than that in control group (P0.01).Auditory neuropathy is an audiology disease with pathological lesions from the VIII cranial nerve to auditory cortex. MEG might become an important reference in decision making for therapies.

To evaluate the value of magnetic source imaging (MSI) in the functional localization of the primary auditory cortex.The M100 waves of cortical auditory evoked magnetic fields (AEFs) evoked by 0.5, 1, 2, 4 and 8 kHz pure tones in 5 subjects and by 2 kHz pure tones in 25 healthy young subjects were measured respectively (16 males and 14 females, with the age from 20 to 32 years old) using a whole head 306 channel magnetoencephalography (MEG) system. The MSI obtained by superimposing functional MEG data on structural magnetic resonance image (MRI) was used to localize the M100 sources on the auditory cortex.The M100 waves of AEFs were clear and replicable in both hemispheres. The M100 sources were localized on the bilateral transverse temporal gyri in all 30 subjects. The localization of M100 on transverse temporal gyri varied with the changes of stimulus frequency. The localization of primary auditory cortex was asymmetrical between bilateral hemispheres, and the left hemisphere M100 dipoles were significantly posterior compared to the right M100 dipoles. The M100 responses appeared significantly earlier to the contralateral stimuli than that to the ipsilateral stimuli in both hemispheres. The dipole positions of M100 were independent of the side of the stimuli.The functional localization of the primary auditory cortex could be determined precisely by magnetic source imaging (MSI) with high spatiotemporal resolution. MSI would hold great promise as a noninvasive tool for the fundamental and clinical research in otology.

To investigate the characteristics of somatosensory evoked magnetic fields (SEF) in patients with acute cerebral infarction by magnetoencephalgraphy (MEG).SEFs were recorded from 17 patients with acute cerebral infarction and 18 healthy volunteers using 306-channel whole-head MEG. The electric stimuli were presented with interstimulus intervals of 0.5 s. The peaks of SEF were estimated by equivalent current dipole (ECD), which were superimposed on MRI.M20 was the most elemental components of SEF in all subjects, originating from the area close to the "hand area" of the primary somatosensory cortex. There appeared several abnormal SEF parameters in the patient group: (1) the value of interhemispheric difference of the M20 positions was (8 +/- 4) mm in the normal group and (11 +/- 3) mm in the patient group (P0.01); (2) the peak latency of M20 responses in the healthy group was (20.7 +/- 1.1) ms, significantly shorter than those in both the unaffected hemisphere and affected hemisphere in the patient group, (21.8 +/- 1.2) ms and (23.6 +/- 1.9) ms, (both P0.01); (3) the strength of ECD in the affected hemisphere was (17 +/- 10) nAm, significantly smaller than that in the unaffected hemisphere, (26 +/- 10) nAm (P0.01).Latent cortical impairment may be evaluated by MEG with higher spatial and temporal resolution. MEG provides objective and sensitive indexes to evaluate the function of somatosensory cortex in patients with acute cerebral infarction.