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1.
This paper is the Part Ⅱ of studying the budget of kinetic energy of the typhoon No. 7507, with the emphasis on the conversion between the kinetic energy of the divergent winds and that of the non-divergent winds, and its relationship to the heating field. The main findings have been brought out as follows.  相似文献   

2.
The partial oxidation of methane to methanol was studied. The effectof various homogeneous "sensitizers" on the oxidation of pure methane was e-valuated at 433℃ and under a pressure of 5.0MPa. It was found that CH_3NO_2was the best one among them. A kinetic study in the presence of CH_3NO_2 wascarried out and the reaction mechanism was discussed.  相似文献   

3.
Observations indicate that the motion of an oceanic mesoscale eddy entering the conti-nental shelf will quickly decay. This shows that the surface area of the eddy continuouslyexpands, and the rotational angular velocity gradually decays with time. Starting from avorticity equation for a vertically stratified, horizontally uniform fluid the above process isdynamically analyzed in this paper. Under the condition to consider the Ekman pump effectof the upper and lower boundary layers and side friction, the analytical models for thesurface area expansion and angular velocity decay of the eddy are deduced.  相似文献   

4.
CONSERVATION OF WAVE ACTION AND EVOLUTION IN THE EDDY   总被引:1,自引:0,他引:1  
The conservation of wave action has been derived with WKB method when the back-ground flow of the eddy is symmetric for axis in a stratified rotative fluid. The necessarycondition of the turbulent evolution in the eddy has been obtained from this conservation.The necessary condition is that the tangent phase velocity of turbulent eddy is equal to therotative angular velocity of the basic flow, or that there is a common revelve circle some-where in the eddy. According to the principle mentioned above the generative and growing condition of thehurricane has been analysed. It has been shown from real data that the vertical circulationin the hurricane may have double circles, from which a possible explanation about the exist-ence of hurricane eye has been given.  相似文献   

5.
The polybutylaldehyde obtained by plasma polymerization was investigated by means of IR, X-ray diffraction, GC-MS, elementary analysis, TEM, electron diffraction and contact angle measurements etc. The results showed that the polymer formed in plasma is amorphous crosslinked polymer, and its backbone is made of carbon atoms. The surface energy of the polymer film is independent of the polymerization conditions. No addition reaction has taken place in the carbonyl group of butylaldehyde in the plasma condition. The result of the wettability measurements showed that the polymer film is generally hydrophobic and the surface energy of the film is about 41 dyn/cm, in which the dispersion force contribution is the majority. The electron diffraction proved that some crystal substance, even the single crystals were present in the polymer. X-ray diffraction also proved the presence of crystal and showed about 15% crystaUinity fraction.  相似文献   

6.
We compute the thermodynamic and the kinetic properties for the reaction:HCOCN→HCH+CO using the statistical theory and the transition-state theory.The equi-librium constants and the rate coefficients of this reaction are also reported here,andthe half lives of formyl cyanide at different temperatures are first estimated in thiswork.  相似文献   

7.
The experiments show that the travelling waves strongly vacillate with time due to the topographic forcing. Otherwise in the experiments with the same imposed external conditions but without topography, the baroclinic waves would travel regularly with almost no vacillation. It was found that a prominent feature in the flow with the topographic forcing is large-scale wave vacillation with a period of 127 annulus rotations, which is equivalent to approximately 26 days in the Earth's atmosphere. The experiments also show that the role of topography is to modulate the unstable baroclinic waves both in space and in time.In the second part of this paper, a series of comparative experiments is introduced to study the influences of heat sources and topography on the large-scale baroclinic background flows defined as the flow patterns determined by Ω, the angular velocity of the annulus rotation and △T, the radial temperature difference between the inner and outer walls of the annulus. The flow patterns depend  相似文献   

8.
On the basis of observatioal data of more than one hundred faults in China and the apparent correlation between fault and megascopic structure, we have studied the zoning of the cataclastic rocks caused by different kinds of faults, and their characteristic types in China. Four distinct zones are recognized in a compressive faults from the centre outwards: crush conglomerate (fault gouge and gravel zone); mylonite——compressed schistose zone; granulated rock——structural lens zone; cataclasite——closely apaesd fracture zone. In addition to the observations in the field, an analysis of the zoning in terms of mechanical principle, experimental determination and tectono-geochemistry has also been made. The zoning reveals the layering and banding of geological bodies, which are of some theoretical and practical significance in mineral exploration.  相似文献   

9.
The glucocorticoid receptor (GCR) of the cytosol of liver and brain was studied by radioligand binding assay, using [~3H] dexamethasone (Dex) as the ligand in lethally and nonlethally scalded rats. As compared with controls, the binding capacity (R_0) was decreased and the apparent K_d of [~3H] Dex specific binding was increased in both scalded groups. In the lethal group, the R_u is much lower than that in the nonlethal group. In order to determine whether the decrease of R_0 was due to the translocation of [~3H] Dex-GCR complex into the cell nuclei, the [~3H] corticosterone (B) specific binding of the hepatic nuclei was measured by the exchange assay. There was no significant difference between the control and scalded groups. The possible mechanisms and the clinical significance of these changes were discussed.  相似文献   

10.
During the ageing of erythrocyte membrane, the spectrin content, Na, K-ATPase activity as well as the lipid fluidity are obviously decreased. However, supplementation of a trace amount of Na_2SeO_3 in the medium could prevent the dissociation of spectrin from membrane and delay the changes of Na, K-ATPase activity and lipid fluidity. The effectiveness is proportional to Se concentration within the range of 0.1—1.0 ppm.Similar effect of supplementation of Se on the intact erythrocytes during ageing has been also observed.The protective action of Se on biomembranes is generally interpreted in terms of the activity of Se-containing glutathione peroxidase (GSHPx). However, GSHPx mainly distributes in the cytoplasma of erythrocytes, therefore it seems that the protective action of supplemented Se on the isolated erythrocyte membrane might not be related to the activity of GSHPx.  相似文献   

11.
The electroreductive conversion of saturated carbohydrates in aprotic media and the subsequent quenching with benzyl bromide results in the formation of benzyl ethers at different C-positions. The application of the semiempirical method AM1 for the calculation of the thermodynamic stability of the intermediate anions formed allows a correct prediction of the observed substitution pattern for the saturated monosaccharides methyl α-d-glucoside, methyl α-d-mannoside, methyl α-d-galactoside, and the unsaturated monosaccharide d-glucal. It is shown that the inclusion of solvent effects via the COSMO continuum model is essential, as it reduces the effect of intramolecular hydrogen bonding as the sole stabilization mode in the gas phase. The results for the disaccharide sucrose are somewhat ambiguous, the three observed substitution positions are among the four most stable calculated anions. This particular system appears to be too complex to be represented by a single conformation.  相似文献   

12.
Systematic studies on the treatment and reuse of the acid industrial watewater containing sodium 2-Naphthylsulfonate(β-salt)from 2-Naphthanol production process by ND-910 resin (made by self) is reported in this paper.Under the operation conditions of initial β-salt concentration of 10000-25000mg/L and initial CODCr of 20000-40000mg/L,the removal rates of Sodium 2-Naphthylsulfonate and CODCr are over 95% and over 89%,respectively.The effluent can be discharged directly after biological degradation.The working sorption capacity of ND-910 Resin for β-salt is over 230g/kg.An alkali-water wash procedure isutilized to regenerate resin and the reclaiming rate of β-salt is over 98%.  相似文献   

13.
The chemisorption intensities of NH_3 and CO on aluminum clusters A1_n(n=l-13)have been theoretically predicted by using CNDO/2 method and properly selecting the clusters'geometries.The results show that the chemisorptions of NH_3 and GO on Al_2,Al_6 and Al_12 aremagically stable and thus are in good agreement with the experimental results.In addition,anelectronic structure analysis is made to expound the nature of such a size effect.  相似文献   

14.
In fresh Porphyra yezoensis, R-phycoerythrin exists mainly as octamer (αβ)_8 with only a small percentage of dimer (αβ)_2.The octamer could be dissociated into dimer in the presence of oxygen and visible light.The dimer was ultracentrifuged in a sucrose linear gradient to obtain the monomer,The monomer could be associated again into dimer.This reversible change between the monomer and dimer of R-phycoerythrin may be attributed to the shift of hydrogen bonds between forms of phycoerythrin molecules.  相似文献   

15.
Acyl isocyanate(Ⅰ) was synthesized by the reaction of acyl chloride with lead cyanate in dichloromethane, using pyridine as a catalyst. Then, adding aryl urea(Ⅱ) to acyl isocyanate, 1-acyl-5-aryl-biuret (Ⅲ) can be obtained. 14 compounds have been synthesized by this method.  相似文献   

16.
In this paper, the study on the ordering path of alkaline feldspar from some volcanic areas by X-ray powder method is presented. The published data by mathematical statistics is treated, a series of formulas and figures to determine chemical composition and degree of Al site occupancy of alkaline feldspar are reset-up, and the simulated function Y=Z~(?) with Thompson's coefficients Y, Z and κ as the indexes of ordering path is suggested. Based on the difference between ordering paths distinguished by κ of alkaline feldspar from volcanic basins, the petrological characters of volcanic basins and the petrological characters of volcanic rocks, some preliminary conclusions of the origin are also summarized.  相似文献   

17.
The effect of isobutylene-isoprene rubber (IIR) on the crystallizing behavior of isotactic polypropylene (IPP) as well as the morphology of the blends in relation with its properties have been studied by DSC, WAXD, polarized light microscope, SEM and mechanical properties test. The experimental results show that IIR has slight influence on melting point, crystallinity, crystallization rate of IPP. It seems certain that IIR has not entered into IPP phase in melt state. IIR has retarding action on the growth of IPP crystal and is an effective nucleating agent of IPP spherulites. The impact strength of the blend increases rapidly with IIR content more than 30 parts; the tensile strength of the blend, however, decreases as IIR content increases. The temperature and time of alter heat-treatment also have great influence on the impact strength of the blend. The impact strength of IPP/IIR (100/20) heat-treated at about 130℃for 2h is 5 times as high as that of the untreated blend.  相似文献   

18.
9-Amino-nonaneic acid was polycondensed in boiling paraffin hydrocarbon medium, the water formed during the reaction was immediately carried away by the vapor of the medium. By using this technique, polycondensation ran very rapidly, and within 15 min. the extent of reaction (p) reached more than 95%, and after 3 hrs., p surpassed 99%. The number average molecular weight was higher than 40,000. These have never been reached as reported in literature.Because p can be pushed to over 99%, it is possible to study the complete course of polycondensation reactions. It was found that the reaction followed second order from the beginning up to p around 99%. Beyond this, the system became so viscous that a viscosity factor should be considered. This caused the reaction to be changed to third order.  相似文献   

19.
There are two kinds of phycoerythrin of different physical properties in Porphyra yezoensis. Their molecular weights are different. They are both composed of a-subunit and β-subunit. Their polymeric forms are (αβ)n. The absorption bands and fluorescence emission bands of the smaller molecules show hypsochromic shifts of several rims relative to that of the polymeric molecules. The isoelectric point of the former is lower than that of the latter. It is worthy of note that the smaller molecules display binding activities with guinea pig antisera. Through using radioimmunoassay, when the depression of the biuding activity of ~(125)I-insulin reaches 50%, the required quantity of the smaller molecules of R-phycoerythrin would be ca. 0.1mg, corresponding to ca. 8μ units of insulin used in a parallel experiment (26 units corresponding to 1 mg of insulin).  相似文献   

20.
Based on the studies on the sediments of the Huanghai Sea (Yellow Sea) formed in thelast glacial period, the complicated palaeogeographic environments of the Huanghai Sea arefound. By the data newly found in the peat and shell layers, it is revealed that the HuanghaiSea is three times exposed and dried as a continent. And the marine sediments are foundfor the first time in the so-called "continental sediment" formed in the early of thelast glacial period. The evolutionary pattern and geological chronicle of natural environ-ments of the Huanghai Sea can primarily be established by the facts that the reversed polarevents of palaeomagnetic variations in the cores are determined and that the peat layer isdated by using ~(14)C.  相似文献   

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