排序方式： 共有32条查询结果，搜索用时 187 毫秒
1.
N. R. Krishnaswamy 《Resonance》1996,1(2):40-46
Chemical methods to determine the conformations and absolute configurations of menthol, a cyclohexane derivative with 3 chiral centres, are described. 相似文献
2.
N R Krishnaswamy 《Resonance》1996,1(7):23-30
Some interesting examples of the linkage between the structure and biological function of secondary metabolites in plants and animals are described. 相似文献
3.
Muhammad Farooq Naseer Manasa Patnam Reehana R. Raza 《Economics of Education Review》2010,29(4):669-683
This paper evaluates the impact of teaching innovations, introduced in public primary schools under the Children Resources International (CRI) Program, on student outcomes. We estimate students’ learning based on their scores on standardized tests. We match schools and children within the treatment and comparison group and find that the CRI Program has been effective in raising learning achievement. Moreover, the results are robust to unobserved selection bias. The average gain for a CRI student represents an improvement of 0.40 standard deviations. The results stay unchanged when we use alternative estimators for the treatment effect including the bias-corrected estimator proposed by Abadie and Imbens (2006). 相似文献
4.
Droplet-based microfluidics has gained extensive research interest as it overcomes several challenges confronted by conventional single-phase microfluidics. The mixing performance inside droplets/slugs is critical in many applications such as advanced material syntheses and in situ kinetic measurements. In order to understand the effects of operating conditions on the mixing performance inside liquid slugs generated by a microfluidic T-junction, we have adopted the volume of fluid method coupled with the species transport model to study and quantify the mixing efficiencies inside slugs. Our simulation results demonstrate that an efficient mixing process is achieved by the intimate collaboration of the twirling effect and the recirculating flow. Only if the reagents are distributed transversely by the twirling effect, the recirculating flow can bring in convection mechanism thus facilitating mixing. By comparing the mixing performance inside slugs at various operating conditions, we find that slug size plays the key role in influencing the mixing performance as it determines the amount of fluid to be distributed by the twirling effect. For the cases where short slugs are generated, the mixing process is governed by the fast convection mechanism because the twirling effect can distribute the fluid to the flow path of the recirculating flow effectively. For cases with long slugs, the mixing process is dominated by the slow diffusion mechanism since the twirling effect is insufficient to distribute the large amount of fluid. In addition, our results show that increasing the operating velocity has limited effects on improving the mixing performance. This study provides the insight of the mixing process and may benefit the design and operations of droplet-based microfluidics. 相似文献
5.
We report a case of a diabetic, heterozygote with near normal hematology, marginally low level of hemoglobin A2(HbA2) having an increased level of hemoglobin F(HbF) that was pancellularly distributed among the red cells. BioRad DiaSTAT measurements
gave a high glycated hemoglobin A1c(HbA1c) of 31.5% and the BioRad Variant analyzer recorded an HbA1c value which was very
low, in discordance with the detected blood glucose levels. Flow cytometry and polymerization chain reaction (PCR) based studies
were carried out which revealed the case to be that of the common hereditary persistence of fetal hemoglobin (HPFH)-3, an
Asian Indian mutation. Fructosamine estimation and HbA1c by Boronate affinity chromatography were able to resolve the discordant
value detected and was able to confirm the diabetes status. The case would have been a diagnostic dilemma, if reported without
correlation. 相似文献
6.
7.
8.
Among the traditional five sensory perceptions, colour and smell often go hand in hand, along with taste. Among the objects used for worshipping God, for instance, flowers and incenses occupy prime places. The subject matter of this article is the chemistry of musk and related perfumes derived from natural sources. 相似文献
9.
10.