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1.
Cinnamomum camphora leaf essential oil (CEO) was extracted using enzymatic-ultrasound pretreatment followed by microwave assisted extraction (EUP-MAE) method and simultaneously studied as a mycelial growth inhibitor against five important pathogens which cause potato dry rot. The optimum EUP-MAE conditions with a real CEO yield of 19.23 ± 0.12 mg/g were obtained through Plackett–Burman design and Box–Behnken design as follows: 3 % of enzyme dosage, 2 h of pretreatment time, 5 of pH, 210 W of ultrasound power, 50 °C pretreatment temperature, 16 mL/g of water to solid ratio, 30 min of microwave time and 500 W of microwave power. Compared to the reference methods, EUP-MAE possessed a highest CEO yield than these of ultrasound-microwave assisted extraction (U-MAE) and traditional hydrodistillation (HD). Gas chromatography-mass spectrometry (GC–MS) analysis demonstrated that eucalyptol, camphor, and α-terpineol were the three main constituents of CEO. Results from in vitro antifungal activity assay revealed that the mycelial growths of all the five tested Fusarium solani, Fusarium culmorum, Fusarium trichothecioides, Fusarium sporotrioides, and Fusarium avenaceum were apparently affected by CEO. These findings not only provide a potential paradigm for the separation of plant essential oil, but also guarantee a promising utilization of the CEO for potato protection to control the Fusarium spp.  相似文献   
2.
In this paper, a class of biholomorphic mappings named quasi-convex mapping of order a in the unit ball of a complex Banach space is introduced. When the Banach space is confined to Cn, we obtain the relation between this class of mappings and the convex mappings. Furthermore, the growth and covering theorems of this class of mappings are given on the unit ball of a complex Banach space X. Finally, we get the second order terms coefficient estimations of the homogeneous expansion of quasi-convex mapping of order a defined on the polydisc in Cn and on the unit ball in a complex Banach space, respectively.  相似文献   
3.
Geometric phase of mixed state is investigated for three-level system obeying a high-temperature master equation. The results show the Berry phase of mixed phase is strongly dependent on the initial condition. For the different initial angle, the turning region is different. In addition, the decrease of Berry phase is most slow around the coupling strength α=5 with an increasing of evolving time.  相似文献   
4.
提出一种利用简并V型三能级原子与光场的Raman相互作用来实现未知的叠加相干态的隐形传送的方案.  相似文献   
5.
6.
A theoretical analysis of the phase stability, electronic and mechanical properties, and Debye temperatures of the C14-type Laves phases (WFe2, MoFe2, WCr2 and MoCr2) has been presented from density functional theory. The phase stability follows the order: WFe2>MoFe2>WCr2>MoCr2. An exchange of electrons takes place between Fe and W/Mo atoms, and there is also electron transfer between Cr and W/Mo. The W–W and Mo–Mo bonds are of the valence character, while the Fe–W/Mo and Cr–W/Mo bonds are of ionic character. The bonding force of A–A is greater than that of A–B in C-14 AB2 type Laves phases (WFe2, MoFe2, WCr2 and MoCr2). The ductility of MoCr2 is higher than others. The hardness of WFe2 (14.1 GPa) is the highest, and the hardness of MoCr2 is the lowest. The incompressibility for these laves phases along c-axis is larger than that along a-axis. The Debye temperature (θD) of MoFe2 is 619 K, which is the highest in those phases. These laves phases also have high melting points, which follows the order: WFe2>MoFe2>WCr2>MoCr2.  相似文献   
7.
Pancharatnam phase and Berry phase are investigated and compared for a three-level atom crosses a double cavity with two near resonant fields. The results show that the time-dependent Pancharatnam phase shows a transitive phenomenon during the evolving process of physical system according to both the time and the space, while the Berry phase as a smooth function of space because of the accumulative effect.  相似文献   
8.
研究某一类迭代级亚纯函数与整函数的复合,在亚纯(整)函数f(z)以及函数g(z)满足一定的条件下得到了复合函数f(g(z))的增长性,推广了原有的一些结果。更多还原  相似文献   
9.
In the Born-Markov approximation and two-level approximation, and using the Bloch-Redfield equation, the decoherence property of superconducting quantum circuit with a flux qubit is investigated. The influence ou decoherence of the mutual inductance coupling between the circuit components is complicated. The mutual inductance coupling between different loops will decrease the decoherence time. However, the mutual inductance coupling of the same loop, in a certain interval, will increase the decoherence time. Therefore, we can control the decoherence time by changing the mutual inductance parameters such as the strength and direction of coupling.  相似文献   
10.
Alkynylstannanes 1 react with Cp2Zr(H)Cl(Cp=η^5-C5H5) giving (Z)-α-stannylvinylzirconium complexes 2, which are trapped with NBS or iodine in THF at 0℃ to stereoselectively afford (Z)-α-bromovinylstannanes and (E)-α-iodovinylstannanes 3, respectively.  相似文献   
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