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排序方式: 共有500条查询结果,搜索用时 93 毫秒
1.
用强子–弦级联模型JPCIAE及相应的Monte Carlo事例产生器研究相对论性核–核碰撞中带电粒子多重数的赝快度密度对能量和中心度的依赖关系.无需另调任何模型参数的条件下,此模型可以同时较好地描述相对论性pp实验数据及PHOBOS和PHENIX实验组的Au+Au实验数据.本文指出:因〈Npart〉并非严格定义的物理量,致使实验上和理论上确定〈Npart〉有一定任意性,从而使得每参加者核子对的带电粒子赝快度密度随着〈Npart〉的增加可能逐渐增大,也可能逐渐减小,因此用它来区分粒子产生机制是欠妥的. 相似文献
2.
The generation of fractals by a generalization of the matrix product is described. These matrix products allow visualization of additional structure of the fractals as well as producing fractals of new types. 相似文献
3.
H. Viernstein S. Reiter P. Wolschann 《Monatshefte für Chemie / Chemical Monthly》1994,125(6-7):681-689
Summary The solubility enhancement of triflumizole, a systemic fungicide, by -cyclodextrin inclusion complexation was investigated by electron absorption spectroscopy. The respective association constant determined by different methods was estimated to 470±20M
–1 in aqueous solution. A model for the host-guest complexation was deduced by molecular calculations.
Löslichkeitsverbesserung von Triflumizole durchHost-Guest-Complexierung mit -Cyclodextrin
Zusammenfassung Die Löslichkeitsverbesserung des systemischen Fungizids Triflumizole durch Komplexierung mit -Cyclodextrin wurde mittels Elektronenabsorptionsspektroskopie untersucht. Die entsprechende Stabilitätskonstante wurde durch verschiedene Methoden erfaßt und betrug im wäßrigen Medium 470±20M –1. Ein Model für denHost-Guest-Complex wurde durch Molekülrechnungen erstellt.相似文献
4.
Jzsef Reiter Lszl Pong Pter Krajcsi Klra Esses-Reiter Pl Sohr Hilda Molnr Pter Dvortsk 《Journal of heterocyclic chemistry》1987,24(4):927-930
The ring-closure of the 5-amino-1-(2-aminophenyl)-3-methylthio-1H-1,2,4-triazole derivatives 3 and 4 with different simple and cyclic C1 components lead to the formation of 1,2,4-triazolo[1,5-α]-1,3,5-benzotriazepines 5–6 , their 4,5-dihydro- 7 , different 5-spiro-homocyclic- 8–13 , and 5-spiro-heterocyclic- 14-15 analogues. The structure of the compounds obtained was proved with the use of their ir, uv, 1H-nmr and 13C-nmr spectra. 相似文献
5.
Two approaches for performing competitive binding immunoassays by HPLC and other flow-based systems are the simultaneous and sequential injection methods. Both these techniques make use of a column with a limited amount of antibody, onto which is injected a sample and a fixed amount of a labeled analyte analog. An indirect measure of the unlabeled analyte in the sample is then obtained by looking at the amount of analog in either the nonretained or retained peaks. In the simultaneous injection mode, the sample and labeled analog are applied at the same time to the column, while in the sequential mode the sample is injected first, followed by the analog. This results in a difference in the analytical characteristics of these two approaches. This study used chromatographic theory and previous data obtained for injections of human serum albumin (HSA) onto an anti-HSA antibody column to compare the response, detection limits, range, and sensitivity of these methods. Under equivalent conditions, it was found that the sequential method always provided the best lower limit of detection and sensitivity. However, the simultaneous mode had a broader dynamic range and higher upper limit of detection. From these observations, several guidelines were developed regarding the use and selection of such assays for new applications. 相似文献
6.
The reaction of isomeric differently methylated 5-amino-3-morpholino-1H-1,2,4-triazolylcarbo-thiohydrazides with ortho esters were studied. Except of the case of triethyl orthoacetate instead of the expected [1,2,4]triazolo[1,5-d][1,2,4,6]tetrazepin-5(7H)-thione ( 6 ) derivatives different rearranged products such as 7, 8, 21, 23, 25 , and 27 were obtained, derivatives 23 and 27 representing a novel ring system. Possible explanations were given for the formation of the rearranged products. 相似文献
7.
8.
A boron-mediated syn- and anti-stereoselective aldol reaction giving rise to various beta-hydroxyenones was coupled to a Pd((II))-mediated oxidative cyclization to give 2,3,6-trisubstituted syn- and anti-dihydropyranones in good yields. The Pd((II))-mediated oxidative cyclization was expanded to alpha-hydroxyenones leading to furan-3(2H)-one derivatives, which include natural product bullatenone and a known precursor of geiparvarin. The sole product of the oxidative cyclization of alpha,beta-dihydroxyenone was a five-membered furan-3(2H)-one derivative, suggesting that the ring closure of these diols is both chemo- and regioselective. 相似文献
9.
2-Substituted-amino-10H-thiazolo[5,4-b]benz[e]indene derivatives 5 representing a novel ring system were synthesized. Their acylation led to exo-acylated derivatives 9 that could be converted to the corresponding glycine analogues 12 . 相似文献
10.
Jzsef Reiter 《Journal of heterocyclic chemistry》1994,31(4):745-748
The structure of the ethoxycarboxylated product of 5-amino-1H-1,2,4-triazole and its hydrazide was corrected using their ir, pmr, cmr and mass spectra. 相似文献