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101.
In this paper, we mainly construct quantization of dimodule algebras and quantum Yang-Baxter H-module algebras, and give some results of smash products and braided products.  相似文献   
102.
以圆柱形毛细管内壁、毛细管内的液体和气体为研究对象.设毛细管液体的表面为旋转面,写出了系统的自由能(表面能及重力势能)的泛函.使自由能泛函取极值的欧拉方程就是关于附加压强的拉普拉斯公式.泛函取极值时在可动边界(毛细管内壁)上的边界条件就可导出关于接触角的杨氏方程.此二方程是自由能取极值的密不可分的两个必要条件.  相似文献   
103.
Wang  Xiaobin  Fu  Xincan  Yan  Jinghua  Wang  An  Wang  Mengqi  Chen  Min  Yang  Chunlong  Song  Yimin 《Molecular diversity》2019,23(3):573-583

A series of novel 2-(6-thioxo-1,3,5-thiadiazinan-3-yl)-N′-phenylacethydrazide derivatives were designed, synthesized and evaluated for their antifungal activities against Fusarium graminearum (Fg), Rhizoctonia solani (Rs), Botrytis cinerea (Bc) and Colletotrichum capsici (Cc). The bioassay results in vitro showed that most of the title compounds exhibited impressive antifungal activities against the above plant fungi. Particularly, the compounds 5c, 5f, 5g, 5i, 5m and 5p displayed desirable anti-Rs activities, with the corresponding EC50 values of 0.37, 0.32, 0.49, 0.50, 0.46 and 0.45 µg/mL, respectively, which are superior to the positive control carbendazim (0.55 µg/mL). Further in vivo bioassay results showed that the anti-Rs activity of title compound 5f at 200 µg/mL reached 95.84% on detached rice leaves and 93.96% on rice plants. Featuring convenient synthesis, novel structures and desirable antifungal activity, these 2-(6-thioxo-1,3,5-thiadiazinan-3-yl)-N′-phenylacethydrazide derivatives could be further studied as the potential candidates of novel agricultural fungicides.

  相似文献   
104.
A series of quinazolin-4(3H)-one derivatives containing a 1,3,4-oxadiazole thioether moiety were designed, synthesized and evaluated for their biological activities against phytopathogenic microorganisms. Antimicrobial bioassays in vitro indicated that most of the target compounds exhibited more significant antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) than the agricultural bactericide thiadiazole-copper. A comparative molecular similarity index analysis (CoMSIA) model with cross-validated q2 and non-cross-validated r2 values of 0.561 and 0.882 was generated to investigate the structure-activity relationships of title compounds against Xoo. Title compound 6w, which was rationally designed under the guidance of obtained CoMSIA model, exhibited the excellent anti-Xoo effect in vitro with an EC50 value of 29.10 μg/mL, which is approximately 3-folds more effective than thiadiazole-copper (113.93 μg/mL). In addition, compound 6i demonstrated the impressive antifungal effects against Rhizoctonia solani (Rs) and Fusarium graminearum (Fg) in vitro, with the corresponding EC50 values of 11.01 μg/mL and 36.00 μg/mL, which is obviously better than the agricultural fungicide hymexazol (76.74 μg/mL and 56.19 μg/mL, respectively). The above researches indicate that quinazolin-4(3H)-one derivatives containing a 1,3,4-oxadiazole thioether moiety could be further studied as template molecules of novel agricultural microbicides.  相似文献   
105.
The present work investigated the enzymolysis kinetics, thermodynamics and model of porcine cerebral protein (PCP) which was pretreated by single-frequency countercurrent and pulsed ultrasound. The kinetic constants for ultrasonic pretreated and traditional enzymolysis have been determined. Results showed that the value of KM in ultrasonic PCP (UPCP) enzymolysis decreased by 9% over that in the traditional enzymolysis. The values of reaction rate constant (k) for UPCP enzymolysis increased by 207%, 121%, 62%, and 45% at 293, 303, 313 and 323 K, respectively. For the thermodynamic parameters, ultrasound decreased activation energy (Ea), change in enthalpy (ΔH) and entropy (ΔS) by 76%, 82% and 31% in PCP, respectively. However, ultrasound had little change in Gibbs free energy (ΔG) value in the temperature range of 293–323 K. Therefore, a general kinetic equation for the enzymolysis model of UPCP by a simple empirical equation was suggested. The experimental values fits with the enzymolysis kinetic model with a low average relative error (4%) confirmed that the kinetic model was accurate to reflect the enzymolysis process. The positive effect of single-frequency countercurrent and pulsed ultrasound in this study and application of the kinetic model may be useful for the release of bioactive peptides from meat processing by-products.  相似文献   
106.
This study investigated systematically the removal of carbamazepine (CBZ) in solution using the combination of ultrasound and persulfate anions to identify the factors affecting the kinetics of the process. The effects of reaction time, initial persulfate anion concentration, initial CBZ concentration, ultrasonic power input, solution pH and temperature on CBZ removal efficiency were examined. The sulfate radical oxidation of CBZ in the presence of ultrasonic irradiation showed a significant synergistic effect on CBZ removal. It is found that up to 89.4% CBZ removal efficiency was achieved after 120 min reaction. The removal process of CBZ in solution could be described using pseudo-first-order kinetics. In this system, sulfate radicals (SO4) were considered to be the mainly oxidant to remove CBZ while ultrasound power input could affect CBZ removal efficiency significantly. Changing solution pH influenced the CBZ removal efficiency and the best performance would be achieved at pH 5.0.  相似文献   
107.
The effect of ultrasound pretreatment prior to convective drying on drying kinetics and selected quality properties of mulberry leaves was investigated in this study. Ultrasound pretreatment was carried out at 25.2–117.6 W/L for 5–15 min in a continuous mode. After sonication, mulberry leaves were dried in a hot-air convective dryer at 60 °C. The results revealed that ultrasound pretreatment not only affected the weight of mulberry leaves, it also enhanced the convective drying kinetics and reduced total energy consumption. The drying kinetics was modeled using a diffusion model considering external resistance and effective diffusion coefficient De and mass transfer coefficient hm were identified. Both De and hm during convective drying increased with the increase of acoustic energy density (AED) and ultrasound duration. However, De and hm increased slowly at high AED levels. Furthermore, ultrasound pretreatment had a more profound influence on internal mass transfer resistance than on external mass transfer resistance during drying according to Sherwood numbers. Regarding the quality properties, the color, antioxidant activity and contents of several bioactive compounds of dried mulberry leaves pretreated by ultrasound at 63.0 W/L for 10 min were similar to that of mulberry leaves without any pretreatments. Overall, ultrasound pretreatment is effective to shorten the subsequent drying time of mulberry leaves without damaging the quality of final product.  相似文献   
108.
A series of polysubstituted furans and dihydrofurans have been prepared from readily available oxodienes and bromonitromethane in modest to excellent yields. This facile synthetic method is developed on the basis of proprietary properties of nitro group such as strong electron-withdrawing ability and cleavability. The conversion of nitro-substituted dihydrofurans to furans is presumably realized by elimination of HNO2 under the aid of DABCO.  相似文献   
109.
杨涛  刘广锦  周璇 《数学杂志》2016,36(6):1111-1119
本文研究了正则乘子Hopf代数上Yetter-Drinfel''d模范畴中自同构代数的问题.利用乘子Hopf代数以及同调代数理论中的方法,获得了Yetter-Drinfel''d模范畴中两个自同构代数是同构的结果,推广了Panaite等人在Hopf代数中的结果.  相似文献   
110.
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