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991.
992.
We describe an improved damage function model for bread dough rheology. The model has relatively few parameters, all of which
can easily be found from simple experiments as discussed in this paper. Small deformations in the linear region are described
by a gel-like power-law memory function. Then, we consider a set of large non-reversing deformations—stress relaxation after
a step of shear, steady shearing and elongation beginning from rest and biaxial stretching. With the introduction of a revised
strain measure which includes a Mooney–Rivlin term, all of these motions can be well described by the damage function described
previously. For reversing step strains, larger amplitude oscillatory shearing and recoil we present a discussion which shows
how the damage function model can be applied in these cases. 相似文献
993.
Rapid resolution liquid chromatography (RRLC) coupled with diode array detection (DAD) and electrospray ionization time‐of‐flight mass spectrometry (ESI‐TOF MS) method was applied to the mass spectral study of a series of naturally occurring iridoid glycosides and phenylpropanoid glycosides in Radix Scrophulariae, which provides higher speed and increased sensitivity without loss of resolution. With dynamic adjustment as the key role of the fragmentor voltage and confirmed with authentic standards, valuable structural information regarding the nature of both the glycoside skeletons was thus obtained. Most compositions were found to possess organic acid moiety such as cinnamoyl, caffeoyl and ferulyol. Besides extensive fragmentation of the carbohydrate moiety, losses of the hydroxyl and glucose residue units showed in the spectra, permitting the exploration of the skeleton and the identity of substituents in the molecule. Ten major iridoid glycosides and 10 phenylpropanoid glycosides were identified or tentatively characterized based on their retention times, UV and TOF MS data. The major fragmentation pathways of PGs in Radix Scrophulariae obtained through the MS data was schemed systematically for the first time, which provides a reference for other PGs derivatives. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
994.
On the Asymmetry for Convex Domains of Constant Width 总被引:1,自引:0,他引:1
The extremal convex bodies of constant width for the Minkowski measure of asymmetry are discussed. A result, similar to that of H. Groemer's and of H. Lu's, is obtained, which states that, for the Minkowski measure of asymmetry, the most asymmetric convex domains of constant width in R2 are Reuleaux triangles. 相似文献
995.
By means of the Cauchy matrix, we give sufficient conditions for the existence and exponential stability of almost periodic solutions and periodic solutions for the delay impulsive logarithmic population. 相似文献
996.
Sinceexcellentantitumoractivityanduniquemechanismofactionofpaclitaxel(taxol@)werediscovered,chemicalstudiesonTaxusspecieshavebeenextensivelycarriedoutl'2.About300taxoidshavebeenisolatedfromGeneraTaxusandAustrotaxusplants'.Insearchforbioactivetaxoidsa... 相似文献
997.
Received January 5, 1997 / Revised version received November 19, 1997 Published online November 24, 1998 相似文献
998.
Wei Shuo FANG* Qi Cheng FANG Xiao Tian LIANG Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Xian Nong Tan Street Beijing 《中国化学快报》2001,(8)
Numerous efforts towards synthesis of anticancer drug paclitaxel (Taxol(r), 1a) with improved activities led to the modification at 13-phenylisoserine side chain and different positions of its core structure-baccatin III 1c1. At the same time, the activities of searching new taxoids for starting materials of new semi-synthetic paclitaxel analogs from Taxus spp. plant have not ever been stopped. Among these taxoids, 14?-hydroxy-10-deacetylbaccatin III 22 and 13-acetyl-9-dihydrobaccatin III … 相似文献
999.
用150fs的掺钛蓝宝石激光系统, 在功率密度约为5×1015 W/cm2时 激励氩(Ar)团簇,利用具有空间分辨能力的平场光栅谱仪观察到13—23nm波段Ar的软x射线谱,并观察到Ar的11阶离子谱线.在较宽的激光脉宽和较低的激光功率密度情况下,通过激励Ar团簇,获得 了Ar的高阶电离度的实验结果,且谱线的信噪比明显好于光场感应电离的情况,说明团簇的 形成大幅度地提高了激光能量的吸收效率.
关键词:
Ar团簇
超短强激光
软x射线辐射 相似文献
1000.
在PTC条件下合成了多亚甲基桥连的双巴比妥类化合物1~3,并通过了元素分析,IR及^1HNMR予以鉴定。 相似文献