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Solar flare is one of the severest solar activities on the sun, and it has many important impacts on the near-earth space. It has been found that flight arrival delays will increase during solar flare. However, the detailed intrinsic mechanism of how solar flares influence the delays is still unknown. Based on 5-years huge amount of flight data, here we comprehensively analyze the flight departure delays during 57 solar flares. It is found that the averaged flight departure delay time during solar flares increased by 20.68% (7.67 min) compared to those during quiet periods. It is also shown that solar flare related flight delays reveal apparent time and latitude dependencies. Flight delays during dayside solar flares are more serious than those during nightside flares, and the longer (shorter) delays tend to occur in the lower (higher) latitude airport. Further analyses suggest that flight delay time and delay rate would be directly modulated by the solar intensity (soft X-ray flux) and the Solar Zenith Angle. For the first time, these results indicate that the communication interferences caused by solar flares will directly affect flight departure delay time and delay rate. This work also expands our conventional understandings to the impacts of solar flares on human society, and it could also provide us with brand new views to help prevent or cope with flight delays., submitted to APJL

The turbulent excitation of torsional Alfven waves is presented on the basis of Lighthill-Stein theory. Due to the special properties of torsional modes, we can apply the theory to the inhomogeneous magnetic flux tube embedded in the solar photosphere, to evaluate the wave energy generated from the turbulent source in the convection zone. Torsional wave spectrum distribution along the r coordinate is achieved. In order to estimate the net wave energy transported to the chromosphere, we investigate the wave propagation and dissipation in the photospheric flux tube by simple phase mixing due to the inhomogeneity. Results for several cases with different model parameters are compared. Conclusions are drawn on the significant role of the energy carried by torsional Alfven waves in the chromospheric and coronal heating, and the wave spectrum may be helpful in understanding the problem of footpoint azimuthal motion of coronal loops.

A high-resolution,nonhydrostatic, three-dimensionalplanetary boundary-layer (PBL) model wasestablished considering the characteristic features of an open-pit mine, which is only (2 km × 2 km) wide and more than 100 m deep. The (E-∈) closure schemes was used in the model. Physical processes such as shortwave radiation of the sun and its uneven distribution on the ground,longwave radiation of earth-atmosphere systems, sensible heat and latent heat and heat flowing into the substrate of the earth, were involved in the model. Using this model PBL structures over this kind of microscale concave terrain (an open-pit mine) were fully studied and numerical experiments on the effects of parameters including H, depth of the mine, α, slope angle of the mine, u, incidcent airflow velocity, and P, indicating shear of the initial velocity, on the PBL were also made. Finally, the evolution process of the PBL was simulated. The results showed that a characteristic and major feature of the PBL is re-circulation, which is greatly influenced by the topography of the mine and the meteorolgical conditions therein. Thermal and mechanical forcing play different but important roles in the evolution process of the PBL.

Based on 297 interplanetary shock waves and corresponding geomagnetic disturbances, the relation between their structures has been studied. For the case in which the interplanetary magnetic field lies basically in the ecliptic plane, we found that (1) the temporal profile of geomagnetic disturbance is mainly determined by the plasma state of the shock waves, especially, the closed relation exists between the plasma temperature profile and the recovery phase of geomagnetic disturbances; (2) shock wave energy transfer index, F s , as defined in the paper, can give a good prediction of the temporal profiles of geomagnetic disturbances. Thus, it may be deduced that there is a basic energy transfer mechanism associated with plasma processes, which would control geomagnetic disturbance profiles, when a southward-component of interplanetary magnetic field is not significant.

We examine a limited parametric study of time-dependent, numerical MHD simulations of coronal mass ejectsion (CMEs). The physical initiating mechanims (at the base of a helmet-streamer magnetic configuration) is assumed to be magnetic flux that emerges from below the photosphere. The peak flux is taken to be viariable in both magnitude and polarity as well as with/without additional physical mechanisms that include emerging mass and momentum flux. We find that magnetic flux of sufficient magnitude and with polarity opposite to that of the overlying helmet’s magnetic field can be a distinct, physically- viable mechanism. We also find: (i) with an appropriate magnetic driver, it is not necesssary to add an arbitrary heating function to a pre-event helmet-streamer, as suggested by Steinolfson and Hundhausen (1988) to produce observed CME features; nor (ii) is it necessary to introduce anad hocaccelerating mechanism to a plasmoid as sugested by Linkeret al. (1990). However, we agree with the latter workers that the CME driving mechanism has the same importance as the configuration of the initial ambient corona in the determination of the mass ejection’s evolution as detected by coronagraphs.

Concentrations of uranium and thorium have been determined for samples of soil from 860 locations in 30 provinces throughout the China. Elevated levels of uranium, thorium, and Th/U as compared with the average world abundance in earth crust were observed. Furthermore, variation of uranium and thorium concentrations with soil types from north towards south China indicates a geochemical weathering pattern and leaching effect on soil development.

The theoretical derivation proposed in this paper uses a specific pseudoinverse technique baesd on an incomplete set of measured modes to satisfy the orthogonality condition. Unlike others, this method demonstrates that the updated model derived from the special pseudoinverse technique does exist in the complete modal space and satisfy the eigenequation. There are three basic, compatible, model characteristics in the updated model: (1) Both low‐order and high‐order modes of the updated model correspond to the measured modes and the analytical high‐order modes of the original finite element model, respectively; (2) the distortion (such as negative eigenvalues) of eigenpairs obtained from the modified model can be eliminated by controlling the high‐order modes of the updated model; and (3) the updated matrices retain the properties of the original finite element matrices, including the banded‐state matrix using the element approach. The derivation of modification formulas in this paper is only based on the ...

We have constructed two recombinant adeno-associated virus (AAV) vectors (pJJ-3GC and pJJ-3ASA) which contained either the human glucocerebrosidase (GC) or arylsulfatase A (ASA) cDNA under the control of an SV40 promoter. These plasmids were co-transfected to 293 cells with a helper plasmid containing trans-acting AAV genes required for packaging the vectors. The two recombinant vectors successfully infected murine and patient fibroblasts. The human glucocerebrosidase and arylsulfatase A genes were expressed at high levels in the cells as determined by Western blot analysis, enzyme assay and immunochemical staining. GC enzyme activity in Gaucher patient fibroblasts (GM-0877) infected by AAV-GC was 15-fold higher than in non-infected cells. ASA enzyme activity in MLD 557g cells infected by AAV-ASA was up to 500-fold higher than in the metachromatic leukodystrophy (MLD) control cells. Southern blotting results showed that the vector integrated 1-2 copies of pJJ-3GC and ASA in the targeted cell genome. These two vectors will be useful in studying AAV-mediated transfer of the GC and ASA genes in cells and animals.

The Hall effects are suggested to be responsible for the decoupling of electrons and ions of magnetic plasma in the process of magnetic reconnection. However, the process that ultimately causes the electrons to diffuse from the magnetic field in the very small diffusion region remains one of the main unsolved problems in magnetic reconnection theory. In this paper, the structure of the Hall electric field in the diffusion region is studied theoretically in the coordinate system located on the magnetic line. A numerical simulation result for this problem is also given. The new discovery is that electrons can be generated in the diffusion region due to the Hall effects. Therefore the role of the Hall effects in the decoupling of electrons and ions of a magnetic plasma can be clarified in the structure of the Hall electric field.

The condition of a direct method for determining ultra trace amount of manganese in serum by controlled-temperature graphite furnace of AA are examined & good results are obtained, i.e. the range of normal serum Nn is between 4.00 to 19.3 ppb, mean value 8.87 Qpb, from 27 adults of good health in Hefei district of China.

Recurrent geomagnetic disturbances are an important part of geomagnetic activities, which are associated with the neutral sheet structure in the heliosphere and the activities of long lived solar coronal holes. Another significant character is the periodic activities recorded by geomagnetic indices. In this paper an algorithm—Adaptive Filtering (AF), is introduced to forecast recurrent geomagnetic events based on the geomagnetic K index. Adaptive filtering can deal with nonstationary data and can adapt to changes in the data pattern. Therefore it is a very helpful method for forecasting the geomagnetic disturbances and the disturbances in the interplanetary space. By using AF technique a prediction for whole Bartels rotation can be obtained when output length is taken as 27-point. For recurrent periods the prediction efficiency is about 30%, the correlation coefficient is 0.55. For nonrecurrent periods the prediction efficiency and correlation coefficient decrease obviously, but the standard variance does not change very much.

Trace amounts of S(2-) can be determined by means of the exchange reaction with the Ag(+)-Cadion 2B complex in presence of Triton X-100 and Na(2)B(4)O(7) solution, by dual-wavelength spectrophotometry. Beer's law is obeyed for the sulphide range 0-2.0 microg/25 ml . The apparent molar absorptivity is 2.65 x 10(5) l.mole(-1).cm(-1). The effect of diverse ions in the presence of EDTA has been studied. The interferences produced by some anions in water samples can be eliminated by precipitation with zinc acetate.

A method developed to determine maximum changes in analytical mass and stiffness matrices to make them consistent with a set of measured normal modes and natural frequencies is presented. The corrected model will be an improved base for studies of physical changes, boundary condition changes, and for prediction of forced responses. The method features efficient procedures not requiring solutions of the eigenvalue problem, and the ability to have more degrees of freedom than the test data. In addition, modal displacements are obtained for all analytical degrees of freedom, and the frequency dependence of the coordinate transformations is properly treated.