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21.
Katsuhisa Mimachi 《Compositio Mathematica》1998,113(2):117-122
We give a short proof of the inner product conjecture for the symmetric Macdonald polynomials of type An-1. As a special case, the corresponding constant term conjecture is also proved. 相似文献
22.
证明如下结果,设X是Banach空间,则X是无限维的充分必要的条件是存在不含内点的非空凸集B,使得B不在任何一个闭超平面上。 相似文献
23.
24.
蒋学锋 《贵州大学学报(自然科学版)》1998,15(2):98-103
本文提出了能快速研究计算机应和新产品满足市场需求的中小型软件开发模型,即“核心功能优先、由里向外扩展”的软件开发模型。 相似文献
25.
S. G. Chung 《Journal of statistical physics》1985,40(1-2):303-328
A fermionic perturbation theory is developed for the statistical mechanics of the nonlinear Schrödinger model. The theory is based on an interacting-fermion picture of the Bethe wave function. The inner product of the Bethe wave function is explicitly evaluated, and a simple graphical representation of it is given. The basic equations obtained for the free energy agree with those of Yang and Yang. In particular, the present theory gives a clear-cut meaning to the function of Yang and Yang: It represents a fermion energy at finite temperatures. 相似文献
26.
The surface area of kaolinite-benzamide (K-Bz)6.62 m2 g–1, whichis noticeably lower than that of kaolinite-dimethyl sulphoxide (K-DMSO) 14.61m2 g–1, the co-perturbationof the inner-surface hydroxyl features at 3697 and 3650 cm–1,and the increase of d(001) value by 7.44 Å are all related to the benzamidespecies inserted into the kaolinite structure through the replacement of theK-DMSO composites. Disappearance of the DMSO reflections and emergence ofwell-defined features at 6.04(2θ) and 11.16(2θ), 001 and 002 reflectionswith d values of 14.62 and 7.92 Å, respectively point out that the DMSOspecies were substituted efficiently by benzamide molecules. The thermal stabilityof the K-Bz derivative up to 300°C can be attributed to the slightly tiltedaromatic ring keying into the gibbsitic sheets via the –NH2groups. 相似文献
27.
1H and 13C NMR spectra of cis- and trans-3-(2-[2-(4-methylphenyl)ethenyl]phenyl])sydnones, the first stilbene-substituted mezoionic oxadiazolium rings, were fully assigned combining the information in various solvents, such as deuterated benzene, acetone and chloroform, using 2D NMR techniques. 相似文献
28.
A rigorous side by side comparison of miniature planar potassium-selective electrodes with hydrogel and potassium hexacyanoferrate(II)/(III) doped polypyrrole (PPy/FeCN) based inner contacts is presented. The planar electrodes were manufactured by screen printing as four- and five-site arrays on ceramic substrates. These electrode arrays were incorporated into a flow-through cell, which could accommodate nine electrode sites. Two identical flow cells were connected in series and the effect of the inner contacts on the analytical performance of the respective electrodes has been critically evaluated. The time necessary to reach steady state conditions has been determined and the effect of experimental parameters (temperature, ambient light intensity, CO2, and O2 concentration of the sample) on the potential stability of the electrodes was analyzed. At controlled temperature, the drift of the planar potassium electrodes with hydrogel and PPy/FeCN solid contact were 0.11±0.02 mV h−1 and 0.03±0.007 mV h−1, respectively. The experimental data proved that there is no aqueous film formation between the PPy/FeCN film and the potassium-selective solvent polymeric membrane. 相似文献
29.
Chemical compounds containing platinum have been employed since 1978 as drugs to beat certain type of tumours. Nevertheless, besides of their exceptional antitumoral properties, these drugs also have important deleterious side effects, such as, nephrotoxicity and ototoxicity.A study of Pt accumulation and a speciation analysis has been performed by ICP-MS in samples from kidney and inner ear in a controlled population of Wistar rats treated with, either, cisplatin, carboplatin or oxaliplatin. The results on Pt accumulation point out to drug structure and not only to Pt content as the responsible for the alteration of organ functionality.Speciation studies in the samples from kidney and inner ear were performed coupling two-dimensional liquid chromatography (2D-LC) to ICP-MS. Size exclusion (SEC) and anion exchange fast protein liquid chromatography (FPLC) was employed for 2D orthogonal separation. After these separations, free drug peaks were not observed in any of the samples.The binding of Pt to biomolecules was demonstrated by SEC and, independently of the drug used, Pt eluted as two main bands with molecular weights of 12 kDa and 25-65 kDa for inner ear samples, and as two different bands with 20 kDa and 50-60 kDa in the samples from kidney. However, the relative band intensity presented important differences for the three drugs. Using the same chromatographic conditions, it was shown that a metallothionein (MT) standard eluted in the same position as some of the cytosolic Pt-biomolecules.High Pt-containing fractions eluting from the SEC column were analysed by anion exchange FPLC after a preconcentration step. Among the different preconcentration methods tested, sample focusing on the head of the FPLC column shows main advantages. In this way, the separation by 2D chromatography of the high molecular Pt-species has been considerably improved. 相似文献
30.
种植沙生植物--沙棘改善内蒙古地区生态环境 总被引:2,自引:0,他引:2
结合内蒙古地区现状,对沙棘的生物学和生态学特性、沙棘属植物化学成分和微量元素及种植沙生植物——沙棘的重要性和必要性进行了详细的研究和探讨。研究表明,沙棘属植物具有极强的生态适应性并富含多种营养成分和生物活性物质,并以耐干旱、耐瘠薄、萌蘖及固氮能力强等特点被称为治理非宜林地水土流失、改善生态环境的先锋树种。种植沙棘是治理内蒙古脆弱生态环境最经济、最有效的措施,是贫瘠的不毛之地发展经济、增加收入的经济树种。另外.种植沙棘的技术简便,容易掌握,投资少,见效快。 相似文献