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111.
In this paper, we present-optimality criteria for convex programming problems associated with exact penalty functions. Several authors have given various criteria under the assumption that such convex problems and the associated dual problems can be solved. We assume the solvability of neither the convex problem nor the dual problem. To derive our criteria, we estimate the size of the penalty parameter in terms of an-solution for the dual problem.  相似文献   
112.
A new measurement of the 200Fr -decay half-life, with improved accuracy compared to previous measurements, has been carried out at the Isolde-CERN on-line mass separator. A half-life of 49(4) ms has been obtained, which is substantially different from earlier literature values. For the 196At daughter decay, a half-life of 389(54) ms and an branching ratio b = 94(5)% were measured. In addition, the half-lives of 201, 203, 205Fr and 197,199At are reported.  相似文献   
113.
Xu J 《Molecular diversity》2005,9(1-3):45-49
A 1H-azeto[2,1-d][1,5]benzothiazepin-1-one, -lactam derivatives of dihydrobenzothiazepines library derived from reactions of 2,4-disubstituted 2,3-dihydro-1,5-benzothiazepines and acyl chlorides, including phthalimidoacetyl chloride, chloroacetyl chloride, dichloroacetyl chloride and phenoxyacetyl chloride, was built up through parallel solution-phase synthesis. Stereochemistry of 1H-azeto[2,1-d][1,5]benzothiazepin-1-ones in the reaction process is discussed.  相似文献   
114.
棉花冠层水分含量估算的高光谱指数研究   总被引:1,自引:0,他引:1  
适宜的光谱指数对于地表参数高光谱诊断模型的估算精度具有决定性作用。通过不同棉花冠层水分含量表征参数冠层等效水厚度EWTcanopy, 植株含水量VWC及其对应的光谱数据分析,构建350~2 500 nm范围内所有波段两两组合的比值指数RVI和归一化指数NDVI,分析水分含量表征参数与所有指数之间的相关关系,筛选最大相关系数对应的指数作为最佳水分指数,利用新指数构建水分含量表征参数的估算模型,并与已知的各种水分指数估算精度进行比较。结果表明:新建比值指数R1 475/R1 424及其归一化指数(R1 475-R1 424)/(R1 475+R1 424)对EWTcanopy的估算效果最佳,由其得到的估算值与实测值之间的相关系数r值达到0.849;已知指数(R835-R1 650)/(R835+R1 650)对VWC的估算效果最佳,由其得到估算值与实测值之间的相关系数r值为0.805。  相似文献   
115.
The structure and optical properties of the films of ternary compounds AgInSe2, CuInSe2 and Cu x Ag1–x InSe2 solid solutions obtained by pulsed laser evaporation are investigated. It has been established that the films like bulk crystals have the structure of chalcopyrite. By the transmission and reflection spectra near the edge of natural absorption the refractive index and coefficient of optical absorption are calculated and the energies of interband transitions and the crystalline and spinorbit splitting are determined.  相似文献   
116.
We review the physical principles which are at the basis of recent field-theoretic computations of the critical exponents in two- and three-dimensional systems. We concentrate on those points that do not show up explicitly in the more standard-expansion: they must be discussed with care if one uses a perturbative approach at fixed space dimensions (the loop expansion). We present in detail simple computations of the critical exponents, while we summarize the results of longer and more accurate computations.  相似文献   
117.
Surimi from silver carp with different salt contents (0–5%) was obtained treated by high intensity ultrasound (HIU, 100 kHz 91 W·cm−2). The gelation properties of samples were evaluated by puncture properties, microstructures, water-holding capacity, dynamic rheological properties and intermolecular interactions. As the salt content increased from 0 to 5%, gel properties of surimi without HIU significantly improved. For samples with low-salt (0–2% NaCl) content, HIU induced obvious enhancement in breaking force and deformation. HIU promoted the protein aggregation linked by SS bonds, hydrophobic interactions and non-disulfide covalent bonds in surimi gels with low-salt content. Moreover, microstructures of HIU surimi gels with low-salt content were more compact than those of the corresponding control samples. HIU also improved the gelation properties of surimi with 3% NaCl to an extent. However, for high-salt (4–5% NaCl) samples, HIU decreased the breaking force and deformation of surimi gels due to the degradation of proteins suggested by increased TCA-soluble peptides. In conclusion, HIU effectively improved the gelation properties of surimi with low-salt content (0–2% NaCl), but was harmful for high-salt (4–5% NaCl) surimi. This might provide the theoretical basis for the production of low-salt surimi gels.  相似文献   
118.
119.
The characteristics and performance of an ionic polymer–metal composite (IPMC), prepared with an anion‐exchange acrylic copolymer, was examined. The acrylic copolymer was synthesized by the radical copolymerization of fluoroalkyl methacrylate and 2‐(dimethyl amino)ethyl methacrylate(AMA). Effects of the AMA repeating unit's content in the copolymer and effects of the anion type present on the actuation of the IPMC were observed. The optimal content of 19.4 wt% AMA in the IPMC copolymer yielded the best actuation. The actuation also improved according to the type of anion present in the composite, in the following order: Br???4 ?.  相似文献   
120.
A new method was applied to modify the surface activity of virginal carbon black (VCB). LA‐57, one kind of hindered amine light stabilizer, was adsorbed onto the carbon black surface through a strong shear force induced by the screws of a HAAKE internal mixer. The modified carbon black (MCB) was characterized by FT‐IR and thermogravimetric analysis (TGA). The bound rubber content of the natural rubber (NR) compounded with MCB and VCB varied with the fraction of LA‐57 on the MCB surface. The nonlinear effect at small strains, generally referred as the Payne effect, was investigated in the rubber compounds based on the different bound rubber contents. The NR compound containing the lowest bound rubber content had an obvious Payne effect. Based on the bound rubber content, the types of filler network varied from direct contact mode to the joint rubber shell mechanism.  相似文献   
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