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1.
This paper proposes a new approach for multi-objective robust control. The approach extends the standard generalizedl
2 (Gl
2) and generalizedH
2 (GH
2) conditions to a set of new linear matrix inequality (LMI) constraints based on a new stability condition. A technique for
variable parameterization is introduced to the multi-objective control problem to preserve the linearity of the synthesis
variables. Consequently, the multi-channel multi-objective mixed Gl
2/GH
2 control problem can be solved less conservatively using computationally tractable algorithms developed in the paper.
Project supported by the National Natural Science Foundation of China (No. 60374028), and the Scientific Research Foundation
for Returned Overseas Chinese Scholars, Ministry of Education (No. [2004]176) 相似文献
2.
A skutterudite-related antimonide, CoFe3Sb12, was prepared with vacuum melting. XRD analysis showed the material contained Sb, FeSb2, CoSb2 and CoSb3 phases. The electrochemical properties of the ball-milled CoFe3Sb12−10 wt% graphite composite were studied using pure lithium as the reference electrode. A maximal lithium inserting capacity
of about 860 mAh/g was obtained in the first cycle. The reversible capacity of the material was about 560 mAh/g in the first
cycle and decreased toca. 320 mAh/g and 250 mAh/g after 10 and 20 cycles respectively.Ex-situ XRD analyses showed that the antimonides in the pristine material were decomposed after the first discharge and that antimony
was the active element for lithium to insert into the host material.
Project supported by the National Natural Foundation of China (No. 59771032) and the RFDP of the Education Ministry of China
(No. 20010335045) 相似文献
3.
The structural characteristics and optical and electrical properties of molecular-beam-epitaxy (MBE) grown ZnS0.8Se0.2 thin films on indium-tin-oxide(ITO) glas substrates were investigated in this work. TheX-ray diffraction (XRD) results indicated that high quality polycrystalline ZnS0.8Se0.2 thin film grown at the optimized temperature had a prefered orientation along the (111) planes. The transmission electron
microscopy (TEM) cross-sectional micrograph of the sample showed a well defined columnar structure with lateral crystal dimension
in the order of a few hundred angstroms. Ultraviolet (UV) photoresponsivity as high as 0.01 A/W had been demonstrated and
for wavelengths longer than 450 nm, the response was down from the peak response by more than 3 orders of magnitude. The thin
ZnS0.8Se0.2 photosensor layer, with a wide energy gap and anisotropic electrical property, makes a transmission UV liquid crystal light
valve (LCLV) with high resolution feasible.
Project supported by the National Natural Science Foundation of China (No. 59910161981) and RGC grant from the Hong Kong Government
Grant (No. NSFC/HKUST 35), China 相似文献
4.
α-diketones and β-diketones react with Grignard reagents in the presence of a catalytic amount of Cp2TiCl2 to yield α-ketols and corresponding ketones respectively. Sulfoxides can be deoxygenated by Cp2TiCl2/Al system. The possible mechanisms are also discussed.
Project (No. 20072033) supported by the National Natural Science Foundation of China and the Specialized Research Fund for
the Doctoral Program of Higher Education Ministry, China 相似文献
5.
Thermodynamic Optimization of DyCl3 -NaCl System 总被引：2，自引：0，他引：2
In this paper, the phase diagram of the DyCl3 -NaCl system is optimized and calculated with CALPHAD ( calculation of phase diagram ) technology. A set of thermodynamic functions of compounds Na3 DyCl6, NaDyCl4, and NaDY2 Cl7 have been optimized and calculated based on an interactive computer-assisted analysis. The optimized thermodynamic parameters, calculated phase diagram and experimental phase diagram are thermodynamically serf-consistent. 相似文献
6.
Well-cubic perovskite lanthanum aluminate (LaAlO3) film on (110) silicon substrate was fabricated by sol-gel method with corresponding inorganic salts. Lanthanum acetate and
aluminum acetate glacial acetic acid solutions were prepared via ligand exchange starting from lanthanum nitrate hexahydrate
and aluminum nitrate hexahydrate after being refluxed. (CH3CO)2O removed nitrates and the crystallized H2O completely, acetylacetone (AcAc) was partially bidentated with metallic ion of the metallic acetates and formed La(OAc)3−x
(AcAc)
x
which were hydrolyzed into La(AcAc)3−x(OH)
x
by adding 10 ml 0.4% methyl cellulose (MCL) solution. The La(AcAc)3−x
(OH)
x
, polymerizing and combining with MCL, formed the LaAlO3 sol precursor with heteropolymeric structure and formed film easily. The epitaxial LaAlO3 film on Si(110) substrate was crystallized after being annealed in thermal annealing furnace for 650–750 °C/30 min. The morphologies
and microstructures were characterized. The refractive index of the LAO film was 1.942 to 2.007; the dielectric constant and
the dissipation factors were estimated to be 23–26 and 2.1×10−4−2.4×10−4 respectively.
Project (No. 2002CB613305) supported by the National Basic Research Program (973) of China 相似文献
7.
8.
The dual formulation of the discrete-time mixedl
2/l
1 control design problem was achieved by using the duality theory of Lagrange multipliers. For some special dual mixedl
2/l
1 problems, an approximation method for the optimal value is introduced. A suboptimal value of the infinite-dimensional dual
problem can be obtained by solving a sequence of truncated problems. The convergence property of the solution scheme is investigated.
This paper gives a low approximation method for the primal problem.
Project(699085) supported by Zhejiang Provincial Natural Science Foundation of China. 相似文献
9.
In this study, supported nonmetal （boron） doping TiO2 coating photocatalysts were prepared by chemical vapor deposition （CVD） to enhance the activity under visible light irradiation and avoid the recovering of TiO2. Boron atoms were successfully doped into the lattice of TiO2 through CVD, as evidenced from XPS analysis. B-doped TiO2 coating catalysts showed drastic and strong absorption in the visible light range with a red shift in the band gap transition. This novel B-TiO2 coating photocatalyst showed higher photocatalytic activity in methyl orange degradation under visible light irradiation than that of the pure TiO2 photocatalyst. 相似文献
10.
Breast cancer is one of the leading causes of death in women today. Some of the patients are hereditary, with a large proportion
characterized by mutation in BRCA1 and/or BRCA2 genes. In this review, we provide an overview of these two genes, focusing on their relationship with hereditary breast cancers.
BRCA1/2 associated hereditary breast cancers have unique features that differ from the general breast cancers, including alterations
in cellular molecules, pathological bases, biological behavior, and a different prevention strategy. But the outcome of BRCA1/2 associated hereditary breast cancers still remains controversial; further studies are needed to elucidate the nature of BRCA1/2 associated hereditary breast cancers.
Project supported by the National Natural Science Foundation of China (No. 30772510) and the Joint Program of Ministry of
Health and Zhejiang Provincal Government of China (No. WKJ2006-2-008) 相似文献
11.
JIANG Xiao-yuan DU Feng ZHANG Xu JIA Yan-rong ZHENG Xiao-ming 《浙江大学学报(A卷英文版)》2007,8(11):1839-1845
Using SnxTi1-xO2 as carriers, CuO/Sn0.9Ti0.1O2 and CuO/Sn0.7Ti0.3O2 catalysts with different loading amounts of copper oxide (CuO) were prepared by an impregnation method. The catalytic properties of CuO/Sn0.9Ti0.1O2 and CuO/Sn0.7Ti0.3O2 were examined using a microreactor-gas chromatography (GC) NO CO reaction system and the methods of BET (Brun- auer-Emmett-Teller), TG-DTA (themogravimetric and differential thermal analysis), X-ray diffraction (XRD) and H2-temperature programmed reduction (TPR). The results showed that NO conversions of Sn0.9Ti0.1O2 and Sn0.7Ti0.3O2 were 47.2% and 43.6% respectively, which increased to 95.3% and 90.9% at 6 wt% CuO loading. However, further increase in CuO loading caused a decrease in the catalytic activity. The nitrogen adsorption-desorption isotherm and pore-size distribution curve of Sn0.9Ti0.1O2 and Sn0.7Ti0.3O2 represented type IV of the BDDT (Brunauer, Deming, Deming and Teller) system and a typical mesoporous sample. There were two CuO diffraction peaks (2θ 35.5° and 38.7°), and the diffraction peak areas increased with increasing CuO loading. TPR analysis also detected three peaks (α, β and γ) from the CuO-loaded catalysts, suggesting that the α peak was the reduction of the highly dispersed copper oxide, the β peak was the reduction of the isolated copper oxide, and the γ peak was the reduction of crystal phase copper oxide. In addition, a fourth peak (δ) of the catalysts meant that the SnxTi1-xO2 mixed oxides could be reductive. 相似文献
12.
Surface morphologies of Zr52.5 Al10 Ni10 Cu15 Be12.5 bulk metallic glass after being rolled at both a temperature around T9 and near （ Tx - 50） K were investigated with a scanning electron microscopy. Macroscopic and microscopic observation results show that squamae, cracks, steps and wedges exist on the surface when the samples were rolled at temperatures around Ty. However, a smooth and fiat surface appears when the samples were rolled at temperatures near （ Tx - 50） K. These results indicate that the mode of deformation in the supercooled liquid region is a partially homogeneous flow at a temperature around T9, and a fully homogeneous one at temperatures near （ Tx - 50） K. According to the results, it is more feasible to roll the amorphous alloys at temperatures near （ Tx - 50） K to obtain parts with smooth and fiat surface. 相似文献
13.
Single phase Fe5C2 intermetallic compound was prepared by mechanical alloying method. The phase and crystal structure of sample were analyzed with X-ray differaction spectrum. The decomposing temperature of the Fe5C2 compound is 596.4℃ determined by the DSC curve. It is further shown that the size of nanometer crystal grain is an important condition for carrying out the solid state reaction at room temperature and normal pressure. 相似文献
14.
In this paper, the Tφ-convex functions were introduced as a generalizations of convex functions. Then the characteristics of the Tφ-convex functions were discussed. Furthermore, some new inequalities for the Tφ-convex functions were derived. 相似文献
15.
Nanostructures enhance phonon scattering and improve the figure of merit of thermoelectric materials. Nanosized CoSb3 skutterudite was synthesized by solvothermal methods using CoCl2 and SbCl3 as the precursors. A “two-step” model was suggested for the formation of CoSb3 based on the X-ray diffraction analysis. The first step is the formation of cobalt diantimonide in the earlier stage during
the synthesis process. Diantimonide was then combined with antimony atoms to form the skutterudite structured triantimonide,
CoSb3, in the later stage of the synthesis process as the second step. The synthesized CoSb3 powders consist of irregular particles with sizes of about 20 nm and sheets of about 80 nm.
Project supported by the National Natural Science Foundation of China (No. 50171064) and the Hi-Tech Research and Development
Program (863) of China (No. 2002AA302406) 相似文献
16.
Ml0.7Mm0.3Ni3.7Co0.7Mn0.4Al0.2 nanocrystalline hydrogen storage materials are prepared by melt-spinning(MS).X-ray diffraction is used for the measurement of the nanocrystalline size.Compared to the electrode of polycrystalline alloys,the property of activation MH9metal hydride)electrode of the alloys with nanometer scale became worse and the inital discharge capacity decreased.It may be ascribed to the decrease of the total amount of rare earth metals and the increase of oxygen on the surface from the analysis of components of the alloys.After heat-treatment,the electrochemical performance of MH electrode of as-spun alloys could be improved,which could be attributed to the alleviation of the lattice strain. 相似文献
17.
In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate
and chromosome aberration rate of Vicia faba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration
of CrO3. We concluded that CrO3 has significant mutagenic effect on Vicia faba root tip cells.
Project supported by Wenzhou Technology Bureau (No. S2002A015) and Wenzhou “551” Talented People Fund of China 相似文献
18.
This paper describes the preparation and properties of TiNx-SiO2 double-layered antireflective(AR) coatings that were applied with print process. The coating material was analyzed and TiNx was used instead of TiO2 as high refractive material. The influence of solution concentration on AR property was studied. The testing result shows that the coatings using print process are featured with excellent mechanical property and the AR property is comparable to American Southwall AR product. It is expected that the study would promote the industrialization progress in AR coatings. 相似文献
19.
Discovery of ultrahigh-T spinel-garnet granulite with pure CO<Subscript>2</Subscript> fluid inclusions from the Altay orogenic belt,NW China 总被引：1，自引：0，他引：1
We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized
by an assemblage of garnet, orthopyroxene spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene
and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the
orthopyroxenes have high XMg and Al2O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which
show peak melting temperatures of around-56.7°C, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a
liquid phase at temperatures around 15.3–23.8°C translating into CO2 of the order of 0.86–0.88 g/cm3. Based on preliminary minerals paragenesis, reaction textures and petrogenetic grid considerations, we infer that the rock
was subjected to UHT conditions. The CO2-rich fluids were trapped during exhumation along a clockwise P-T path following isothermal decompression under UHT conditions.
Project supported by the National Basic Research Program (973) of China (No. 2001CB409801), the Exemplary Young Teacher Education
and Scientific Research Award Plan of China University, and Postdoctoral Fund of China (No. 2003033033), Postdoctoral Fund
of Zhejiang Province, and Starting Fund of Education Ministry, China 相似文献
20.
Ｉｎ 1935 ,Ｐ .Ｅｒｄ¨ｏｓａｎｄＧＳｚｅｋｅｒｅｓｏｂｔａｉｎｅｄｔｈｅｃｌａｓｓｉｃａｌｉｎｅｑｕａｌｉｔｙＲ (ｍ ,ｎ)≤Ｒ (ｍ - 1,ｎ) Ｒ(ｍ ,ｎ - 1) . Ｉｎ 196 8,Ｋ .ＷａｌｋｅｒｐｒｏｖｅｄｔｈａｔＲ(ｎ ,ｎ)≤ 4Ｒ(ｎ- 2 ,ｎ) 2 . Ｉｎ 1998,ＨｕａｎｇＹ .Ｒ .ａｎｄＺｈａｎｇＫ .Ｍ .[1,2 ] ｐｒｏｖｅｄｔｈａｔＲ(ｍ ,ｎ)≤ 12 (β 3γ 5 ) 12 γ(4α 2 β - 3γ 6 ) (β 1) 2 Ｉｎｔｈｉｓｐａｐｅｒ ,ｗｅｏｂｔａｉｎｓｏｍｅｎｅｗｕｐｐｅｒｂｏｕｎｄｓｆｏｒＲ(ｍ ,ｎ ,ｌ)ａｎｄＲ(ｍ … 相似文献