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71.
The non-isothermal crystallization behaviors of polyamide 6/clay nanocomposite (PA6CN) were investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). DSC results showed that the nanometric silicate layers in PA6CN acted as effective nucleation agents. The addition of silicate layers influenced the mechanism of nucleation and the growth of PA6 crystallites. The DSC results also implied an unusual phenomenon, in contrast to PA6, the crystallinity degree of PA6CN increased with increasing cooling rate. XRD results verified this phenomenon and indicated that the addition of silicate layers favored the formation of the γ crystalline form. 相似文献
72.
在20 L标准球形爆炸罐内开展了当量比为1的甲烷-氢气-空气混合气体爆炸实验,通过改变点火能量和氢气体积分数,探讨点火能量和气体比例对其爆炸压力和爆炸强度的影响。研究发现:氢气比例越高,爆炸冲击波传播速度越快,点火能对冲击波传播速度的影响相对较小;点火能量的提高对峰值超压有增强作用,氢气比例低时,此增强作用较显著,氢气比例高时,此增强作用较弱;点火能量对爆炸强度指数KG的影响较小,而氢气比例对爆炸强度指数KG的影响十分明显,氢气比例低于50%时,氢气比例的增加对爆炸强度的增强作用较弱,氢气比例高于50%时,氢气的增加对爆炸强度的激励作用急剧增强。另外发现,相同当量比条件下,氢气的爆炸强度指数近似为甲烷爆炸强度指数的10倍。 相似文献
73.
In this paper, we study the non-isentropic compressible magnetohydrodynamic system with a time periodic external force in Rn. Under the condition that the optimal time decay rates are obtained by spectral analysis, we show that the existence, uniqueness and time-asymptotic stability of time periodic solutions when the space dimension n ≥ 5. Our proof is based on a combination of the energy method and the contraction mapping theorem. 相似文献
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Zhong-Quan Liu Yankai Zhao Haiqing Luo Lingzhi Chai Qiuju Sheng 《Tetrahedron letters》2007,48(17):3017-3019
The mild and efficient nature of HIO3 and I2O5 as environmentally benign, commercially available, atom efficient, and safe reagents for the oxidation of alcohols has been demonstrated. Additionally, these oxidants are highly chemoselective, and effect smooth room temperature oxidation of various electron-rich alcohols with catalytic amounts of KBr in water. 相似文献
77.
Yanhui Li Qiuju DuTonghao Liu Yan QiPan Zhang Zonghua WangYanzhi Xia 《Applied Surface Science》2011,257(24):10621-10627
Enteromorpha prolifera was pyrolyzed to prepare activated carbon using chemical activation by zinc chloride. The effect of activation parameters such as activation temperature, weight ratio (Enteromorpha prolifera to ZnCl2), and activation time was investigated. The BET results showed that the surface area and pore volume of activated carbons were achieved as high as 1722 m2/g and 1.11 cm3/g, respectively, in the optimal activation conditions. Batch adsorption studies were carried out to study the adsorption properties of cationic red X-GRL onto activated carbon by varying the parameters like initial solution pH, contact time, and temperature. The kinetic studies showed that the adsorption data followed a pseudo second-order model. The isotherm analysis indicated that the adsorption data could be represented by the Langmuir isotherm model. The Langmuir monolayer adsorption capacity of cationic red X-GRL was estimated as 263.16 mg/g at pH 6.0. 相似文献
78.
Qiuju Bian Ronald J. Gould Paul Horn Susan Janiszewski Steven La Fleur Paul Wrayno 《Graphs and Combinatorics》2014,30(5):1099-1122
We investigate pairs of forbidden subgraphs that imply a 3-connected graph is Hamiltonian-connected. In particular we show that the pair {K 1,3, P 9} is such a pair. As it is known that P 10 cannot replace P 9, this result is best possible. Further, we show that certain other graphs are not possible. 相似文献
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