Five sterylglycosides (acylmono-, mono-, di tri- and tetraglycosylsterol) and a saponin were isolated from Adzuki beans and
characterized. In the glycosylsterols, the principal component sterols were sitosterol and stigmasterol; the major sugar component
was glucose. The glucose units were shown to be linked by β1,6-bonds. The three oligoglycosylsterols were shown to be gentiobiosylsterol,
gentiotriosylsterol and gentiotetraosylsterol; the latter two are novel sterylglycosides. The saponin was identified as glucopyranosyl-(β1→2)-glucopyranurosyl-(β1→3′)-soyasapogenol
B (Azukisaponin I) which had previously been found in Adzuki beans. 相似文献
The analysis procedure outlined in this paper essentially makes use of the existing isotropic theories of torsion suitability modified to account for the non isotropic nature of typical carbon fibre composite material.
The warping and St Venant torsional stiffnesses of the beams are determined using the appropriate equivalent engineering elastic constants of the composite material which correspond to the membrane and bending modes of action respectively.
The differential equation governing the constrained torsional equilibrium of the open section beams is solved exactly in the paper for Z and channel sections with some emphasis being given to the influence of ply stacking sequence.
Theoretical results are presented in graphical form and these depict the variations in warping displacement, warping shear flow and longitudinal or axial constraint force intensity with applied torque for the cantilever beam condition with torque applied at the free end.
The paper also gives details of finite element studies of the composite beams and of an experimental programme of work pertaining solely to the behaviour of composite Z beams.
Comparisons between theory, finite element and experiment are presented and these are seen to give exceptionally close agreement.
It is clearly indicated that fibre orientation significantly influences the restrained torsional behaviour of thin-walled open-section composite beams. It is also clear that the use of the appropriate equivalent engineering elastic material constants in the theory is able to closely predict actual behaviour. 相似文献
This paper estimates the real gross domestic product (GDP) and unrecorded economy for Turkey using the Kalman filter technique. Using different tests, most of the research articles on energy policy investigate the causal relationship between energy consumption and GDP for different countries. On the other hand, other studies on climate change try to show the effects of both energy consumption and GDP on carbon dioxide (CO2) emission. Since the unreported economy has an important weight in developing countries where the recorded (or official) GDP suffers from considerable measurement problems, investigation of the relationship between the recorded GDP and energy consumption may lead to biased results. In this paper, the economic variables (GDP, country population) as well as environmental variables (CO2 emission, forest area) are used in order to estimate GDP, which is an unobserved variable in our model. The results clearly indicate that: first, the true GDP in Turkey, that our model estimates, is higher than the observed (recorded) GDP in the whole period of observation (1973–2003) and the size of unrecorded economy varies between 12 and 30 percent of the observed GDP; second, the gap between the true GDP and the observed GDP has an increasing trend; third, if the change in GDP per primary energy supply is smaller than the change in CO2 per primary energy supply, then there may exist unrecorded economy. 相似文献
In this study, activated carbon cloths (ACCs) were modified in a glow-discharge apparatus by using 2-hydroxyethyl-methacrylate (HEMA), dimethyl-aminoethyl methacrylate (DMAEMA), and hydroxymethyldisiloxane (HMDS) plasmas. Scanning electron micrographs exhibited the formation of the polymeric films on the ACCs after glow-discharge modification. The adsorption experiments were performed using model solutes, i.e., creatinine, vitamin B-12, and trypsin. No significant change was observed in the adsorption capacities of the ACC/PHEMA and ACC/PDMAEMA composites compared with the original ACC adsorption capacity. However, there was a pronounced decrease in the case of the ACC/PHMDS. Oxygen permeabilities of both the original and modified ACCs were measured in a flow-through gas chamber. The oxygen permeabilities of the original and modified forms were 817 and 3.5-5 cm3/s.cm2.cm Hg x 10(-7), respectively. Water-vapor permeabilities of the composites were obtained by using a standard water-cup assembly. Permeabilities varying between 921 and 10,300 g/m2.day were found. Microorganism impermeabilities of the ACCs were demonstrated by using model PS monosize polymeric particles with a diameter of 0.2 micron. The particle permeability of the original ACC was 65.6 mg/m2.day. Almost no particle permission was observed through the modified ACCs. 相似文献
The current density in the fuel cell is the direct consequence of reactions taking place over the active surface area. Thus, measurement of its distribution will lead to identification of the location and nature of reactions and will give opportunity to improve the overall efficiency of fuel cells. Within this study, the current density distribution in a direct methanol fuel cell was analyzed by segmenting the current collector into nine sections. Besides, the effect of the different operating parameters such as molarity, flow rate and reactant gas on the current density distribution was analyzed. 相似文献
Control chart patterns are important statistical process control tools for determining whether a process is run in its intended mode or in the presence of unnatural patterns. Accurate recognition of control chart patterns is essential for efficient system monitoring to maintain high-quality products. This paper introduces a novel hybrid intelligent system that includes three main modules: a feature extraction module, a classifier module, and an optimization module. In the feature extraction module, a proper set combining the shape features and statistical features is proposed as the efficient characteristic of the patterns. In the classifier module, a multi-class support vector machine (SVM)-based classifier is proposed. For the optimization module, a particle swarm optimization algorithm is proposed to improve the generalization performance of the recognizer. In this module, it the SVM classifier design is optimized by searching for the best value of the parameters that tune its discriminant function (kernel parameter selection) and upstream by looking for the best subset of features that feed the classifier. Simulation results show that the proposed algorithm has very high recognition accuracy. This high efficiency is achieved with only little features, which have been selected using particle swarm optimizer. 相似文献
We report a study of thermal stability and impact of thermal pretreatment procedures for 46% Pt/Vulcan XC72 (Tanaka) fuel cell catalyst. Stability in air and in inert gas (nitrogen, argon, helium) has been investigated by thermal gravimetric analysis (TGA), TGA‐mass spectrometry (TGA‐MS) and differential scanning calorimetry (DSC). Two distinct low temperature mass loss processes (100–200 and 285–300 °C) were observed, each exhibiting unique pretreatment temperature dependencies. TGA‐MS data in helium show fragment ions that suggest the thermal degradation processes are associated with decomposition of materials such as processing aids. Transmission electron microscopy (TEM) reveals a modest increase in average Pt nanoparticle size upon thermal pretreatment. After a pretreatment protocol based on TEM and thermal characterisation (300 °C/15 min, N2), the electrochemically active surface area did not increase. At the kinetically controlled potential region (E >0.8 V) there was a small drop in current density for treated 46% Pt/C in comparison with as‐received catalyst. The slowing in ORR kinetics is significant. Apparently, the removal of organic components, which would improve mass transport, is negated by increased nanoparticle size. 相似文献
Functional near-infrared spectroscopy (fNIRS) is an emerging technique for monitoring the concentration changes of oxy- and deoxy-hemoglobin (oxy-Hb and deoxy-Hb) in the brain. An important consideration in fNIRS-based neuroimaging modality is to conduct group-level analysis from a set of time series measured from a group of subjects. We investigate the feasibility of multilevel statistical inference for fNIRS. As a case study, we search for hemodynamic activations in the prefrontal cortex during Stroop interference. Hierarchical general linear model (GLM) is used for making this multilevel analysis. Activation patterns both at the subject and group level are investigated on a comparative basis using various classical and Bayesian inference methods. All methods showed consistent left lateral prefrontal cortex activation for oxy-Hb during interference condition, while the effects were much less pronounced for deoxy-Hb. Our analysis showed that mixed effects or Bayesian models are more convenient for faithful analysis of fNIRS data. We arrived at two important conclusions. First, fNIRS has the capability to identify activations at the group level, and second, the mixed effects or Bayesian model is the appropriate mechanism to pass from subject to group-level inference. 相似文献