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141.
Caixiang Zhang Yanxin Wang Xifeng Yan 《Colloids and surfaces. A, Physicochemical and engineering aspects》2006,280(1-3):9-16
The adsorption behavior of activated carbon (AC) prepared from the residue of diosgenin by-product was characterized. The adsorption capacities of AC such as iodine, phenol and methylene blue (MB) are 933.28, 145.38 and 165 mg/g, respectively. The results of MP analysis and BJH method show AC has developed micropore and mesopore volumes, which are 0.1621 and 0.2623 cm3/g respectively, with the mean pore diameter of 1.49 nm. Comparison of the liquid phase adsorption capacities of AC to the standard activated carbon (SAC) and the commercial activated carbon (CAC) for wastewater treatment showed AC was superior to SAC and CAC. Experiments on phenol and MB adsorption and COD and chroma removal from diosgenin wastewater were carried out under different conditions of contact time, temperature, concentration, adsorbent dose and pH. The removal of COD and chroma of 10-multiple wastewater is 92.46 mg/g and 88 %, respectively. Adsorption parameters for the Langmuir and Freundlich isotherm models were determined. At lower temperatures, the data for phenol and COD fitted Freundlich model better than Langmuir model and vise versa for MB and chroma. Adsorption followed second-order kinetics. The study proves that AC prepared from the residue of diosgenin by-product can be used as adsorbent for the treatment of diosogenin wastewater as a cost-effective approach of resource recycle of Discorea zingiberensis C.H. Wright. 相似文献
142.
提出了用光电混合网络来完成自适应取阈功能的硬件实现方法。该网络系统能根据输入状态的不同,通过网络单元间的相互竞争而达到对系统的阈值的自适应调整,使阈值总是等于最大输入值而完成“胜者全取”(WTA)。该网络系统主要由非晶硅半导体PIN光电探测阵列和“胜者全取”电子网络组成。又由于系统完全采用并行处理方式,因而具有响应速度快、灵敏度高、寻址能力强、结构简单和性能稳定等优点,能方便有效地应用于自适应取阈、相关峰检测、联想存储等光电混合系统,对一个36个单元的网络进行了实验测试并对其性能进行了分析。 相似文献
143.
144.
Yanxin Yu Jinmao You Zhiwei Sun Zhongyin Ji Na Hu Wu Zhou Xuxia Zhou 《Journal of separation science》2019,42(4):826-833
In this study, a simple analytical method for the determination of γ‐aminobutyric acid, gabapentin, and baclofen by using high‐performance liquid chromatography with fluorescence detection was developed. An amidogen‐reactive fluorescence labeling reagent, 4‐(carbazole‐9‐yl)‐benzyl chloroformate was first used to sensitively label these analytes. The completed labeling of these analytes can be finished rapidly only within 5 min at the room temperature (25°C) to form 4‐(carbazole‐9‐yl)‐benzyl chloroformate labeled fluorescence derivatives. These labeled derivatives expressed strong fluorescence property with the maximum excitation and emission wavelengths of 280 and 380 nm, respectively. The labeled derivatives were analyzed using a reversed‐phase Eclipse SB‐C18 column within 10 min with satisfactory shapes. Excellent linearity (R2 > 0.995) for all analytes was achieved with the limits of detection and the limits of quantitation in the range of 0.25?0.35 and 0.70?1.10 μg/L, respectively. The proposed method was used for the simultaneous determination of γ‐aminobutyric acid and its analogs in human serum with satisfactory recoveries in the range of 94.5–97.5%. 相似文献
145.
Yanxin Wang Dapeng Peng Yufei Zhu Shuyu Xie Yuanhu Pan Dongmei Chen Yanfei Tao Zonghui Yuan 《Journal of separation science》2019,42(10):1915-1929
A facile and sensitive multi‐residue detection approach of pressurized liquid extraction following high‐performance liquid chromatography tandem mass spectrometry was established to detect the residues of adrenergic drugs, steroids, sedative, colorant and antioxidant in feed. The conditions employed for pressurized liquid extraction involved acetonitrile/ethyl acetate (1:1, v/v) as the extracting solvent, the temperature 80°C, two cycles and a static time of 10 min. The extraction was followed by a solid‐phase extraction clean‐up step. The separation of samples was done by C18 column with the mobile phase of 5 mM ammonium acetate solution and acetonitrile with 0.1% formic acid. The limits of quantification ranged from 0.03 to 1 μg/kg, limits of detection were in a range of 0.01–0.5 μg/kg, and average recoveries were 70.4–98.6%. The pressurized liquid extraction procedure was optimized and overall method was validated in terms of sensitivity, linearity, selectivity, matrix effect, accuracy, recovery and stability of the target drugs in the pressurized liquid extraction extracts solution. The screening method was proved to be fast, selective, accurate and sensitive for screening drugs. 相似文献
146.
Shao Yunhai Wang Yanxin Yi Fengmei Zhang Yanan Liu Wangqian Yang Chen Meng Hui Cui Peiwu Zhong Weihong 《Applied biochemistry and biotechnology》2019,189(1):262-272
Applied Biochemistry and Biotechnology - Formaldehyde is harmful to human beings. It is widely used in chemical industry, medicine, and agriculture and is frequently discharged into the sewage.... 相似文献
147.
148.
Kinetics of glass transition and crystallization in multicomponent bulk amorphous alloys 总被引:4,自引:0,他引:4
Differential scanning calorimeter (DSC) is used to investigate apparent activation energy of glass transition and crystallization
of Zr-based bulk amorphous alloys by Kissinger equation under non-isothermal condition. It is shown that the glass transition
behavior as well as crystallization reaction depends on the heating rate and has a characteristic of kinetic effects. After
being isothermally annealed near glass transition temperature, the apparent activation energy of glass transition increases
and the apparent activation energy of crystallization reaction decreases. However, the kinetic effects are independent of
the pre-annealing. 相似文献
149.
150.
一种用于多目标旋转不变分类识别的神经网络模型及算法 总被引:1,自引:0,他引:1
提出了一种适于光学实现的神经网络模型和算法,通过对3种飞行器平面内旋转投影较的识别,证明了该方法具有对多目标转动不变的模式识别能力。 相似文献