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1.
Huang Benwen 《武汉大学学报:自然科学英文版》1997,2(4):405-410
The characterization ofA
5 is obtained through the method of calculation. The main result is described as the following:
Supported by the Natural Science Foundation of Hubei Province
Huang Benwen: born in Oct. 1948, Associate professor 相似文献
| 1) | The order ofA 5 is one, two, three or five. |
| 2) | The element ofA 5 is divided into five conjugate classes. |
| 3) | There are fifty and nine subgroup inA 5 and we can obtain one produce element in every subgroup. |
| 4) | There are nine conjugate classes in the subgroup ofA 5. |
2.
Conclusions
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| 1. | The high-temperature pyrolysis reaction of cellulose and organic matter have an optimal reaction condition: 95°C, 4–14 mg cellulose, and 15–30 min. |
| 2. | Under the optimal condition, the formed CO or CO2, and the sample have the same λ18O value. It is unnecessary to recover oxygen from CO. |
| 3. | The data are accurate and reliable, and the operation method is simple and economic. |
3.
Conclusions
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| 1. | The eclogite dikes in low-greenschist facies epi-metamorphic volcaniclastic rocks in the Dabie Mountains areas show magma origin rather than tectonic melange or metamorphic origin. |
| 2. | Coesite and quartz pseudomorphs in the eclogite show that they were formed at the pressure of over 2.8 GPa and belong to ultrahigh pressure type. Therefore, there were high-pressure eclogite magma at deep crust depth. |
| 3. | From the country rock age of the low-grade metamorphic volcaniclastic rocks, we infer that the eclogite dikes were formed after the Sinian. |
4.
Conclusions
相似文献
| 1) | Using conventional deposition techniques of heating or e-beam evaporation, the effect of the substrate’s temperature cannot be neglected. If the substrate temperature is not uniform, the uniformity of the film thickness and the film’s composition may change. But with magnetron sputtering deposition, the effect of the substrate temperature is almost absent. |
| 2) | It is known that various of evaporation depositions, such as ion sputtering deposition and other physical vapor depositions can hardly be used to prepare large-area uniform films. At present, magnetron sputtering deposition is the best preparation method of large-area uniform films. |
| 3) | With the quartz crystal monitor of film thickness and suitably designed film structures, films of less than 0.2% reflectivity in visible region can be obtained. |
5.
Yanzhong Zhang 《科学通报(英文版)》1997,42(14):1218-1222
Conclusions
相似文献
| (1) | The newly developed nanocrystalline Fe72 Cu1Nb2V2Sil4 B9 and Fe72Cu1NblMo1-V2Si14B9 alloy still show the superior synthetical magnetic properties quite comparable with those of the early developed and typical Fe-Cu-Nb-Si-B alloys. Their cost has been reduced, the ductility of their amorphous ribbons is much better than that of Fe-Cu-Nb-Si-B alloys, and their ribbons can be folded back without brittleness. |
| (2) | In the range off = 20–2000 kHz and Bm = 0.05-0.6 T, the dependences of core loss on frequency and amplitude flux density can be expressed asPoc B2 mfn,n = 1.6-1.7. |
| (3) | In the range of f= 20–2000 kHz and (B m f) = (15−30) × 103 T·Hz, the approximate expression 1nP = [a(Bm,f) +b] (lnf)-n is tenable, wheren =0.2-0.3, and botha andb are constant. |
| (4) | The newly developed nanocrystalline alloys have been used in switching mode power supply with larger output power, unipolarity pulse transformer and precision current mutual inductor and clearly shown advantage. |
6.
Conclusions
相似文献
| 1. | Over the past 8 000 years, notable changes in moist regime and temperature took place in Caohai District. The peat archives in this area recorded some hemispheric climatic events, such as three new ice ages and the Medieval Warm Period occurring in the northern hemisphere. This indicates that this area is sensitive to global changes. |
| 2. | Over the past 8 000 years, Caohai District is typical of the warm-moist—cool-dry climate. |
7.
Conclusions
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| (1) | Based on strict kinetics of chemical reactions, MCT-GC method can provide detailed information for generation of organic components. Through computer, we can obtain the yield of the total hydrocarbon or individual component for any geological period under given gmlogical conditions by combining MCT-GC data with geological perameters, and apply them to basin modeling, petroleum prediction, and so on. |
| (2) | n-Alkanes with high molecular weights were generated very early due to their low activation energies, e. g. fig. 3 shows that almost 98% of C24 has been generated within 20 Ma, while only 1% of C12 was generated. |
| (3) | Because equipment condition was limited, kinetics of methane, which is one of the most important component in petroleum exploration, is not discussed in this note. Our further work will focus on kinetics of methane through a modified MCT-GC set. |
8.
Conclusion According to the calculated results for the dissociation mechanism of C4H4O+, we come to a conclusion as follows:
相似文献
| (1) | Reaction (1) of C3H4 + formation and reaction (2) of CH2CO+ formation are both the processes involving three steps. The first and the second step of the reactions are the same. |
| (2) | The first step of H-transfer of the two reactions are the rate determining step, whose UMP2//6-31G barrier is 280.5 kJ · mol−1, which is comparable to the experimental value. |
9.
Conclusion
相似文献
| 1 | The dispersion capacity of MoO3 supported on CeO2 is 0.81 rnmo1/100 m2. For samples with MoO3 content is below the dispersion capacity, Mo6+ ions exist in the surface vacancies to form the surface Mo species, and the highly dispersed Mo6+ cations are coordinated by 7 oxygen ions based on the assumption that the CeO2(111) plane is preferentially exposed. |
| 2 | The differences of the dispersions between MoO3 on CeO2 and MoO3on ZnO-modified CeO2 indicate that the surface vacancies play an important role in the dispersion of MoO3. |
10.
Conclusions
相似文献
| 1. | Topologic analysis of representative Devonian graphoglyptids of China shows that a huge graphoglyptid clan can be grouped into three kinds of topologic configurations homeomorphic to line, tree and network, which correspond to foraging, probing feeding and the catching and feeding of constructing and inhabiting in anoxic, suboxic and dysoxic2) deep-water environments respectively. |
| 2. | It is well known that, in paleoecology and paleontology, morphologic features are bases of functional morphologic analysis of body and trace fossils, but, the features are not only Euclidean geometric, but also topologic and fractal geometric. In terms of the topologic graphoglyptids homeomorphic to line, tree and network, the functional morphologic analysis based on topologic configuration can reveal trace producer’ s ethology and ecological function mysteries contained in trace fossils from new aspects. |
| 3. | A functional topologic morphologic analysis first can get rid of interference of original biogenic traces to be subjected to compacting, diagenesis and deformation. In addition, it can simplify existing classification and naming system of ichnology, enrich and develop the theory and methodology of a functional morphologic analysis. |
11.
Conclusions
相似文献
| 1. | It is a successful attempt to test and study O-Si stable isotopic composition of SiO2 shells of radiolarian of sediment core below the depth of 5 000 m in the Pacific Ocean because of lacking of calcium shells below CCD in ocean. The distribution and variation, from 21.2 X 10−3 to 34.5 × 10−3 for δ18OSMOW and from 0.2 × 10−3 to 1.2 × 10−3 for δ30SiNBS-28, have certain link with and difference from those of other oceanic organisms. |
| 2. | The relationship between δ18O and δ30Si values indicates obviously that the humeric distribution of core samples from No. 1787 station shows two groups separated by the depth of 160 cm. This distribution is also recorded by two kinds of isotopic curves (fig. 2(a), (b)), reflecting the evolutional difference of oceanic environment and stratigraphic sequence between the upper and lower layers separated by the depth of 160 cm. |
| 3. | Through a correlation of δ18O values, the core from No. 1787 station shows that since 27 Ma, the Pacific Ocean has experienced 7 cold/warm changes, accompanied by the frequent variations of global ice volume and sea level. |
12.
Compressibility of a natural kyanite to 17.5 GPa 总被引：1，自引：0，他引：1
The compressional behaviour of a natural kyanite, (Al1.99Fe0.01)SiO5, has been investigated to about 17.5 GPa at 300 K using a diamond-anvil cell and synchrotron X-ray diffraction. The pressure–volume data fitted to the third-order Birch–Murnaghan equation of state (EoS) yield an isothermal bulk modulus (K0T) of 192 ± 6 GPa and pressure derivative () of 6 ± 1. When is fixed as 4, the derived K0T is 201 ± 2 GPa. These values are in excellent agreement with most experimental determinations in the literature. Consequently, it can be concluded that the compressibility of kyanite under high pressures has been accurately constrained. 相似文献
13.
After choosing weight functions suitably, we define a Banach spaceH
ω
μ
(L) and discuss the generalized inverse of singular integral operators on an open arc. Using the generalized inverse, we obtain
the solutions for the following singular integral equation
Hence, we extend and unify the method of solution for characteristic equations with Cauchy kernel and Hilbert kernel.
Foundation item: Supported by the National Natural Science Foundation of China(No. 201980633).
Biography: Li Hong-yan(1971-), female, Master, research interest: singular integral equations. 相似文献
14.
SHANG LinBo BI XianWu HU RuiZhong FAN WenLing 《科学通报(英文版)》2007,52(3):395-400
Using the solubility method, the solubility of CuCl2 in liquid-undersaturated HCl-bearing water vapor was investigated experimentally at temperatures of 330-370 ℃ and pressures of 4.2-10 MPa. The re-sults have shown that hydration could significantly enhance copper solubility and the concentrations of copper were positively correlated with PH2O. The solubility of copper in vapor phase increased with increasing PH2O at the constant temperature. CuCl2 was transported as hydrated species CuCl2(H2O)ngas in water vapor. The formation of complexes is proposed to be the result of the following reaction: CuCl2solid nH2Ogas = CuCl2 (H2O)ngas The hydration number n decreased slightly with increasing temperature. Statistical hydration numbers are 4.0, 3.6 and 3.3 at 330, 350 and 370 ℃ , respectively. 相似文献
15.
Suppose that A is an n × n positive definite Hemitain matrix. Let X and Y be n × p and n × q matrices (p+ q≤n), such that X* Y = 0. The following inequality is proved
X*AY( Y* AY)-Y Y*AX≤( (λ1-λn)/(λ1+λn))2 X*AX,
where λ1 and λn are respectively the largest and smallest eigenvalues of A, and M- stands for a generalized inverse of M. This inequality is an extension of the well-known Wielandt inequality in which both X and Y are vectors. The inequality is utilized to obtain some interesting inequalities about covari-ance matrix and various correlation coefficients including the canonical correlation, multiple and simple correlation. 相似文献
16.
HE Zhenya CHEN Hua 《武汉大学学报:自然科学英文版》2007,12(3):391-394
We consider the following non-linear elliptic equation △u＋ f（x,u）=0,x∈K on fractal domains with zero-Dirichlet boundary conditions, where K is self-similar fractal, △ is the Laplacian defined on K. f（x, t） is asymptotically linear as t→ ∞. We get the non-trivial and non-negative solution by using Mountain Pass lemma. 相似文献
17.
Relative contribution of individual strengthening mechanisms to the yield strength of Mg–0–15 wt%Gd alloys were investigated.Alloys with different grain size were prepared by adding Zr and hot extrusion.Hardness and tensile/compression yield strength were tested on the alloys after solid solution treatment and extrusion.HallPetch constants were calculated with hardness and tensile/compressive data.The results showed that the hardness of Mg–Gd alloys with similar Gd content and different grain size were almost the same,which indicates that grain size had little effect on hardness.The hardness linearly increased with rising Gd content(d H_v/dc≈25 kg mm~(-2)/at%Gd).The tensile and compressive yield strengths enhanced with the increase of Gd content for all alloys in different conditions.In addition,the tensile/compressive(t/c)yield asymmetry of extruded alloys decreased with increasing Gd content.Large t/c yield asymmetry ratio(1.77)was observed for pure Mg,and with increasing Gd content this value decreased to 1.With the increasing of tensile strength,the stress intensity factor,k_y,decreased from 0.27 MPa m~(1/2)for Mg–2 wt%Gd alloy to 0.19 MPa m~(1/2) for Mg–5 wt%Gd alloy,then increased to 0.29 MPa m~(1/2) for Mg–15 wt%Gd alloy.However,k_yincreased linearly form 0.16–0.31 MPa for compression test.The influence of grain size strengthening was eliminated,and the yield strength of tension and compression both linearly increased with c~n,where c is the atom concentration of Gd,and n=1/2 or 2/3. 相似文献
18.
The effects of Ce on the secondary dendrite arm spacing (SDAS) and mechanical behavior of Al-Si-Cu-Mg alloys were investigated. The reduction of SDAS at different Ce concentrations was evaluated in a directional solidification experiment via computer-aided cooling curve thermal analysis (CA CCTA). -The results showed that 0.1wt%-1.0wt% Ce addition resulted in a rapid solidification time, △TS, and low solidification temperature, △TS, whereas 0.1wt% Ce resulted in a fast solidification time, △ta-Al, of the α-Al phase. Furthermore, Ce addition refined the SDAS, which was reduced to approximately 36%. The mechanical properties of the alloys with and without Ce were investigated using tensile and hardness tests. The quality index (Q) and ultimate tensile strength of (UTS) Al-Si-Cu-Mg alloys significantly improved with the addition of 0.1wt% Ce. Moreover, the base alloy hardness was improved with increasing Ce concentration. 相似文献
19.
Let G =(V_1,V_2,E) be a balanced bipartite graph with2 n vertices.The bipartite binding number of G,denoted by B(G),is defined to be n if G =K_n and min i∈{1,2}|N(S)|n min |N(S)|/|S|otherwise.We call G bipancyclic if it contains a cycle of every even length m for 4 ≤ m ≤ 2n.A theorem showed that if G is a balanced bipartite graph with 2n vertices,B(G) 3 / 2 and n 139,then G is bipancyclic.This paper generalizes the conclusion as follows:Let 0 c 3 / 2 and G be a 2-colmected balanced bipartite graph with 2n(n is large enough) vertices such that B(G) c and δ(G)(2-c)n/(3-c)+2/3.Then G is bipancyclic. 相似文献
20.
Gan Shixin 《武汉大学学报:自然科学英文版》1997,2(1):13-18
In this paper we prove the following Hàjek-Rènyi inequality: Let 0≤p≤1, then for any Banach spaceB, anyL
p integrableB valued random variable sequence {D
n
, n≥1}, any real number sequence {b
n
, n≥1} with 0<b
n, ↑ ∞, any integern≥1, there exist a constantC=C
p>0 (only depending onp) such that
In the other direction, we prove some strong laws of large numbers and the integrability of the maximal functions forB valued random variable sequences by using this inequality and the Hàjeck-Rènyi inequality we have obtained recently. Some
known results are extended and improved.
Supported by the National Natural Science Foundation of China and the State Education Commission PH. D Station Foundation
Gan Shixin: born in Feb. 1939, Professor 相似文献