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101.
The root and leaf essential oils, present in trace amounts in Amsonia illustris Woods. (Apocynaceae), were isolated by steam distillation and their chemical constituents identified by GC-FID and GC-MS. More than 80% of the thirty volatile compounds in the leaf oil were identified, the major constituents being mainly sesquiterpenes like a-humulene (14.5%), beta-caryophyllene (12.4%) and guaiol (11.6%). The volatile ingredients of the root oil were pinocampheol, methyl salicylate, (2E,4E)- decadienal, eugenol and trans-isoeugenol. 相似文献
102.
Acta Mathematica Hungarica - We show that bisymmetry, which is an algebraic property, has a regularity improving feature. More precisely, we prove that every bisymmetric, partially strictly... 相似文献
103.
The cellular structure of Norway spruce (Picea abies) was transformed via a simple, single‐step carbonization process into a carbon monolith with molecular‐sieve properties. The monolith exhibited a genuine honeycomb structure derived from the original intrinsic H2O channels of the wood. The micropores formed during carbonization from the walls of the channels were shown to have a high adsorption capacity. The honeycomb monolith was tested for air separation. Micropore diffusion of N2 and O2 was found by the frequency‐response (FR) technique to be the rate‐controlling process of mass transport. 相似文献
104.
Simple, reproducible preparative methods are described for the production of the title compounds from diacetone glucose. 相似文献
105.
106.
Summary We describe the simplest system which shows stochastic resonance. A linear(ized) theory for white and (almost) arbitrarily
coloured noise is presented. The presented new system has new, unique properties which originate from itsnon-dynamical character; for example, the strength and phase shift of periodic response of the system is independent of the frequency.
Experiments have been carried out with the following noise processes: (physical) white noise, (physical) Lorentzian noise
and (physical) 1/f noise. With a small extension of the system, its linear-response regime can be significantly increased. As the system is
similar to some simple models of neurones, the new results might have not only physical but also biological importance.
Paper presented at the International Workshop “Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena”, Elba, 5–10 June 1994. 相似文献
107.
Multiphoton ionisation of different order was measured from the energy levels of the atoms He, excited in a low current glow discharge. 相似文献
108.
The general intensity dependence of the five-photon ionization probability of triplet metastable helium was measured. 相似文献
109.
Dynamic and stepwise purity test techniques were compared, and it was established that in dynamic measurement the sample in many cases can not be considered to be in a state of equilibrium from the thermodynamic aspect. The problems of the measuring time and the accuracy of the results are discussed for the two-peak method, applicable for the processing of data obtained by the stepwise technique. It was established that the two-peak method can be improved. By using several peaks, the accuracy of the results and measuring time can be optimized. 相似文献
110.
J. Kiss 《Helvetica chimica acta》1967,50(5):1423-1430
In the sulfatide fraction of beef spinal-cord, isolated according to the method of BLIX [9] and LEES [14], there are also sulfatides present derived from 2S, 3R-1, 3-dihydroxy-2-amino-octadecane. 相似文献