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1.
Based on the WIND observational data for the plasma waves from thermal noise receptor (TNR) working on the frequency 4-256 kHz and the solar wind and the magnetic fields, we analyze the plasma wave activities in the 60 magnetic cloud's boundary layers (BLs) and find that there are often various plasma wave activities in the BLs, which are different from those in the adjacent solar wind (SW) and the magnetic clouds (MC). The basic characteristics are that: (1) the enhancement of the Langmuir wave near the electronic plasma frequency (fpe) is a dominant wave activity, which occupies 75% investigated samples; (2) the events enhanced both in the langmuir and ion acustic (f〈fpe) waves are about 60% of investigated samples; (3) broadband, continuous enhancement events in the plasma wave activities were observed in the whole frequency band of TNR, and about 30% of the 60 samples, however, were not observed in the SW and the MC investigated events; (4) although the ratio of the temperatures between the electon and proton, Te/Tp ≤1, the ion caustic wave enhancement activities are still often observed in the BLs, which makes it difficult to explain them by the traditional plasma theory. New results reported in this paper further show that the magnetic cloud's BL is an important dynamic structure, which could provide useful diagnosis for understanding the cloud's BL physics and could expand a space developing space plasma wave theory.  相似文献   

2.
The knowledge that hydrostatic pressure is equal to the gravity value of the overlying rocks in studying a dynamic state of certain underground site is argued. It is suggested that the stress field T in the crust is a combination or superposition of total hydrostatic pressure P with differential stress σ , and the total hydrostatic pressure P at any point in the crust comprises two parts: one is spherical stress tensor PG caused by the gravity, and the other is spherical stress tensor Ps caused by tectonic stress; therefore P could not be attributed to the gravity of overlying rocks only. The results obtained by a finite-element simulation indicate that the tectono-original additional hydrostatic pressures Ps decrease gradually from the compressive zone (Pcs) to the shear zone (PSHs) and to the tensile zone (PTs), i. e. PCS>PSHs> PTs in the same depth. On the basis of the above-mentioned research, the method of measurement and calculation of metal logenetic depth corrected by Ps is established, i.e. first tectonic additional hydrostatic pressure Ps is removed from general hydrostatic pressure P to get PG, gravity additional pressure, then accordingly the depth data are measured and calculated. The plastic deformation of garnet in coesite-bearing eclogite, quartz eclogite and garnet amphibo-lite of the ultrahigh-pressure metamorphic (UHPM) complex in the Yingshan County in Dabie Mt. is studied by the transmission electron microscope (TEM). It is shown that the garnets have ductile deformation in the metamorphic condition of eclogite and amphibolite facies. Microstructures of the garnet vary greatly among coesite-bearing eclogite, quartz eclogite and garnet amphibolite. The tectonic principal stress in three-dimensional space and the tectonic additional hydrostatic pressure are reconstructed by differential stress and strain ratio (α) of garnet in minor coesite-bearing eclogite, then the gravity and thickness of overlying rocks are determined. The formation depth of ≥ 32.09-32.106 km of the coesite-bearing eclogite in Yingshan County in the Dabie UHPM zone is obtained from difference PG which comes from P minus Ps, Ps = (σ1 + σ2 + σ3) /3. The value of P is 2.8 GPa resulting from Qz-coes geobarmeter. This result is at all different from other researchers' conclusion that the formation depth of eclogite in Dabie UHPM zone is ≥100 km by the method of weight/ special weight (W/SW). The strong tectionic action makes a great contribution to the formation of e-clogite in the Dabie UHPM zone at so shallow depth of about 32 km, therefore it is thought that attention should be paid to the tectonc-original additional hydrostatic pressure in the study on UHPM zone.  相似文献   

3.
In this paper, we prove an extrapolation theorem of operators in martingale spaces with A p weights, which shows that for operators T defined on martingale space L u 1 , if T is bounded on martingale space L p0(w) for some 1 < p 0 < ∞ and every, wA , so it is on L p,s (w) for every 1 < p, s < ∞, and wA . We also get some properties of A p weights and prove that if wA 1, then the maximal operator M is bounded on L p,q (w) with 1 < p < ∞, 1 < q ≤ ∞.  相似文献   

4.
Some weak asymptotic results for average σ-K width and average σ_L width of the isotropic Besov classes S r pθB(R d), S r pθb(R d) and the anisotropic Besov classes S r pθB(R d), S r pθb(R d) in L p(R d) (1≤p<∞) are obtained, and the corresponding weak asymptotic optimal subspaces are identified. Furthermore, the weak asymptotic behavior of optimal recovery is established for the isotropic Besov classes S r pθB(R d) in L p(R d) (1≤p≤∞).  相似文献   

5.
The compressional sound velocity Vp for enstatite of polycrystalline specimens were measured at pressures from 40 to 140 GPa using the optical analytical techniques under shock loading. The dependence of VP, (in km/s) on Hugoniot pressure (P, in GPa) can be described by InVp= 3.079-0.691 In(P) + 0.094(lnP)2. Vp satisfies Birch’s law:V p = 4.068 + 1.677ρ, where ρ is corresponding density, which indicated that enstatite is stable throughout the conditions of the lower mantle. The wave velocityP is 0.5% lower and the wave velocity S is 2% higher than that of PREM respectively. We concluded that the lower mantle is mainly composed of perovskite-(Mg1-x, Fex) SiO3 and only a small amount of (Mg1-x, Fex) O is allowed in it.  相似文献   

6.
限制的星划分问题   总被引:1,自引:1,他引:0  
 研究了边赋权图上2类具有权重限制L的最小基数星划分问题-最小基数S(L)划分问题和最小基数S∑(L)划分问题的困难性.得到如下结果:①证明了一般图上最小基数S(L)划分问题的NP-完全性;②证明了一般图上最小基数S∑(L)划分问题的NP-完全性,并证明了对于任意小的正数ε,一般图上的最小基数S∑(L)划分问题不存在(3/2-ε)-近似算法,除非P=NP.  相似文献   

7.
Differences in the thermodynamic functions between the liquid and crystalline states of La-based bulk metallic glasses alloys were calculated with the specific heat capacity Cp and the fusion heat ΔHf,which we measured. Fragility indexes having different thermodynamic definitions were calculated from the temperature dependence of excess entropy ΔSliq-cry. It is ambiguous for La-based glass-forming liquid to evaluate fragility from the intercepts of ΔSliq-cry-temperature curves. We found that the thermodynam...  相似文献   

8.
0 IntroductionMaalnadria siusb atr ompajicosr .he aAltrthe pmrisoibnlienmi (n qtihneghtraoopsiucs,QHS,Fig.1) is a sesquiterpene endoperoxide isola-ted fromArtemisia annuaL., an ancient Chineseherbal medicine usedfor treatment of fever and ma-laria.Studies of the structure and activity relation-ship have shownthat endoperoxide groupis essentialfor anti malarial activity of QHS and absence of thismoiety lead to completely loss in activity of thedrug. Many techniques have been developed to de…  相似文献   

9.
The rate constants for the ozone reactions with n-butyl methyl sulfide (n-BMS, CHaCH2CH2CH2SCH3), sec-butyl methyl sulfide (s-BMS, CH3CH2(CH3)CHSCHa) and tert-butyl methyl sulfide (t-BMS, (CH3)3CSCH3) were measured using our smog chamber under supposedly pseudo-first-order conditions at 30002 K and 760 Torr. The experimental determined rate constants for n-butyl, s-butyl and t-butyl methyl sulfide are (1.23 ± 0.06)×10-19, (5.08 ± 0.19)×10-20 and (2.26 ± 0.14)×10-20 cm3 molecule-1· s-1, respectively. The reactivity-structure relationship of the reactions was discussed and used to illustrate the mechanism of the ozone reaction with thioethers. The results enrich the kinetics data of atmospheric chemistry.  相似文献   

10.
The spin-forbidden reaction 1HNO(^1A+OH^-→3NO^-(^3∑^-)+H2O has been extensively explored using vari- ous CASSCF active spaces with MP2 corrections in several basis sets. Natural bond orbital (NBO) analysis, together with the NBO energetic (deletion) analysis, indicates that the two isomers have nearly equal total energy and could compete with each other in the title reaction. More significantly, the singlet/triplet surface crossing regions have been examined and the spin-orbit coupling (SOC) and energetics have been computed. The computational results indicate that the SOC is very large at the crossing point T1/S0 trans (ca. 40.9 cm^-1). Moreover, the T1/S0 trans has a low energy of 10.67 kcal/mol relative to that of trans-So. Therefore, the surface crossing to the triplet state seems much more efficient at the T1/S0 trans region along the minimum energy path (MEP), However, The values of single (P1^ISC) and double (P2^ISC) passes estimated at T1/S0 trans show that the ISC occurs with a little probability.  相似文献   

11.
The effect of Ni addition on the glass-forming ability (GFA) and soft-magnetic properties of an (Fe1-xNix)75.5B14.5P7Nb3 (x=0-0.6) alloy system were investigated. We found that the addition of Ni was effective in allowing the alloy to approach a eutectic point as well as increasing the thermal stability of the supercooled liquid. By increasing the amount of Ni,the supercooled liquid region (ΔTx),the reduced glass transition temperature Trg (Tg/Tl) and the Y parameter [Tx/(Tg+Tl)] increased from 49 to 75 K,0...  相似文献   

12.
Synthesis of ligand, α-oxo-pentanedioic acid benzoyl hydrazone (H2LPB), and its six rare earth (La, Pr, Nd, Sm, Gd and Er) complexes are reported. The composition and the properties of the complexes were characterized by element analysis, thermal analysis, UV, IR and1H NMR spectra. Besides, relaxivity (R 1) of Gd-complex has been determined by INVREC.Au program, using inversion recovery pulse sequences, R1=8.05 mmol · L−1 · s−1. The acute toxicity of Gd-complex in animal has also been tested, and the median lethal dose (LD50) is equal to (468.2±30) mg/kg.  相似文献   

13.
A tree decomposition of graph G=(V, E) is referred to as a partition of edge set E into edge-disjoint trees. Given (not necessarily distinct) vertices u-1, u-2...u-k∈V with k≥2, a sufficient and necessary condition is given for a connected graph G=(V,E) to have a tree decomposition {T-1, T-2...T-k} such that V(T-i)=V{u-i}, i=1,2,... k.  相似文献   

14.
Spin-crossover complexes are of great interest to the scientists because of their potential application in molecular-based electronic devices. Some octahedral metal compounds with 3dn (4 ≤ n ≤ 7) configuration can induce a spin state conversion through a fine tuning condition (temperature, pressure, light irradiation, etc.). If the conversion occurs reversibly with a hystersis loop and color change, it will make the system possessing memory effect. The memory effect can be magnified and the …  相似文献   

15.
The reaction of a typical unsaturated alcohol, 3-methyl-3-buten-1-ol (MBO331), with Cl atoms, was investigated for the first time. The reaction was investigated using discharged flow-tube coupled with electron impact mass spectrometer. The experiments were performed over the temperature range of 248 K-298 K and at pressure of 1 torr in He as the bath gas. The obtained kinetic data were used to derive the Arrhenius expression: k1 = (3.47 ± 1.21) × 10^-11 exp[( 599 ±69)/7] cm^3 molecule^-1 s^-1. Finally, atmospheric lifetimes of the MBO331 with respect to OH radicals, NO3 radicals and CI atoms have been calculated and the atmospheric implications are considered briefly.  相似文献   

16.
Generalized ridge estimation of a semiparametric regression model   总被引:1,自引:0,他引:1  
We considered the following semiparametric regres-sion model yi = X iT β+ s ( t i ) + ei (i =1,2,,n). First,the general-ized ridge estimators of both parameters and non-parameters are given without a restrained design matrix. Second,the generalized ridge estimator will be compared with the penalized least squares estimator under a mean squares error,and some conditions in which the former excels the latter are given. Finally,the validity and feasibility of the method is illustrated by a simulation example.  相似文献   

17.
We give a condition on the couple of weights(u,v) for Doob's operator to be a bounded one from martingale space Lp(u) to function space Lp(v) .Moreover,we also obtain necessary and sufficient conditions in order that the maximal geometric mean operator is bounded from martingale space Lp(u) to function space Lp(v) or Lp,∞(v) .  相似文献   

18.
We have investigated the effects of high magnetic fields on the microstructures and magnetic properties of Fe-Si-O films deposited by RF sputtering. Three typical sample appearances, hole-in-center, phase-separation and hybridization were obtained for the Fe-Si-O films prepared in the oxygen-argon flow ratio VO2/Vtotal<1.0%, magnetic field Bappl≤1.0 T regime, indicating that not only the distribution of plasma but also the angular distribution of sputtered atoms are influenced by a high magnetic field. In the oxygen-argon flow ratio VO2/Vtotal>2.0%, magnetic field Bappl≥2.0 T regime, strong (110) orientation of Fe3O4 grains and larger remanence and coercivity measured in the direction normal to the film plane appeared in the Fe-Si-O films. This result indicates that the high magnetic fields not only orient the Fe-Si-O film but also induce remarkable perpendicular magnetic anisotropy during the deposition.  相似文献   

19.
Outcrossing rate in a natural population of Caldesia grandis was estimated by the dominant random amplified polymorphism DNA (RAPD) marker using 10 open-pollinated progeny arrays of 24 individuals. The multilocus outcrossing rate estimated based on all 25 RAPD loci was 0.872 ±0.033 and the single-locus outcrossing rate was 0.795 ±0.032. Multilocus estimates did not differ significantly from the single-locus estimates. The fixation index, F, in the progeny estimated from RAPD data was -0.142 ±0.000. The estimates of multilocus outcrossing rates (t_m) and single-locus outcrossing rates (t_s) obtained from MLDT clearly indicate that outcrossing is predominant in the open-pollinated C. grandis population. An empirical analysis suggests that 15 should be the minimum number of dominant marker loci necessary to achieve robust estimates of t_m.  相似文献   

20.
Zn-5wt% Al eutectic alloy was directionally solidified with different growth rates (5.32–250.0 μm/s) at a constant temperature gradient of 8.50 K/mm using a Bridgman-type growth apparatus. The values of eutectic spacing were measured from transverse sections of the samples. The dependences of the eutectic spacing and undercooling on growth rate are determined as λ=9.21V-0.53 and ΔT=0.0245V0.53, respectively. The results obtained in this work were compared with the Jackson-Hunt eutectic theory and the similar experimental results in the literature. Microhardness of directionally solidified samples was also measured by using a microhardness test device. The dependency of the microhardness on growth rate is found as Hv=115.64V0.13. Afterwards, the electrical resistivity (r) of the casting alloy changes from 40×10-9 to 108×10-9 Ω·m with the temperature rising in the range of 300–630 K. The enthalpy of fusion (ΔH) and specific heat (Cp) for the Zn-Al eutectic alloy are calculated to be 113.37 J/g and 0.309 J/(g·K), respectively by means of differential scanning calorimetry (DSC) from heating trace during the transformation from liquid to solid.  相似文献   

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