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51.
采用物理法将稻壳炭化,炭化料用酸碱处理,固体残渣经高温水蒸汽活化制备活性炭,脱灰液体采用沉淀法制备SiO2. 结果表明,用2.5 mol/L NaOH溶液按液固比10 mL/g脱灰的炭化料所制活性炭比表面积为961.8 m2/g,比不脱灰炭化料所制活性炭增加136%,总孔容积增加103.8%,对碘和亚甲基蓝的吸附容量分别为1270和300 mg/g. 在10% HCl、煅烧温度600℃条件下所制SiO2粒径为40~60 nm,为无定型结构,比表面积达330 m2/g,纯度达99.84%. 相似文献
52.
Hong Khanh Dieu Nguyen Toan Dang Nguyen Dung Ngoc Hoang Duc Sy Dao Thao Tien Nguyen Limphirat Wanwisa Lan Linh Hoang 《Korean Journal of Chemical Engineering》2017,34(2):314-319
Hydrotalcite-like compound containing metal cations such as Mg2+, Al3+ and Ni2+ was characterized using Ni K-edge EXAFS and in situ Ni K-edge XANES techniques for clarifying its bonding environment around Ni2+ sites and structure changes during calcination from room temperature to 550 °C, respectively. At the fixed molar ratio of Mg/Ni/Al of 2/1/1, the results obtained from EXAFS analysis showed a slight blue shift before and after the calcination at 550 °C and a reduction in white line peak; the best fits of the two samples revealed tiny change in coordination number about 7 for Ni-O path but considerable difference for Ni-Mg(Al) path from about 4.5 to 9.5, confirming a modification from brucite like to mixed oxide structure. On the other hand, bond distances of the Ni-O and Ni-Mg paths nearly fixed at about 2.06 Å to 3.0 Å reflected stability of the cationic bond order on each plane, but partial collapse and decomposition of the interlayer formed by water molecules and anion CO 3 2? after the calcination. Linear combination fit extracted from the in situ Ni K-edge XANES also confirmed the changes along with the calcination such as slow and fast decreases of brucite fraction at 150 °C and 330 °C, respectively, in corresponding to the mixed oxide fraction increases. The achieved bonding structures were also applied to explain acid-base occurrence of the hydrotalcite-like material, especially the acid sites generated by different static charges along with the bonds. The explanation was illustrated by NH3-TPD method. 相似文献
53.
54.
Minh Van Nguyen Sigurjon Arason Gudjon Thorkelsson Agusta Gudmundsdottir Kristin Anna Thorarinsdottir Boi Ngoc Vu 《Journal of the American Oil Chemists' Society》2013,90(3):317-326
Effects of added phosphates on retardation of lipid oxidation of salted cod during processing, storage and after rehydration were investigated. Lipid hydrolysis progress and development of color, primary and secondary lipid oxidation products and fluorescence intensities were determined. Added phosphates significantly retarded lipid hydrolysis and lipid oxidation progress, resulting in lower free fatty acid , lipid hydroperoxides (PV), thiobarbituric acid-reactive substances (TBARS) as well as fluorescence intensities (δF or and δF aq). Significant correlation between the lipid oxidation products (PV, TBARS, δF or and δF aq) and yellow/brownish discoloration (b* value) of salted cod was observed. Principal component analysis showed that TBARS, b* value and δF or were the strongest indicators of lipid oxidation during salting and storage. 相似文献
55.
Differential Expression Analysis of a Subset of Drought-Responsive GmNAC Genes in Two Soybean Cultivars Differing in Drought Tolerance 总被引:1,自引:0,他引:1
56.
John Z Wen Sophie Ringuette Golnaz Bohlouli-Zanjani Anming Hu Ngoc Ha Nguyen John Persic Catalin F Petre Y Norman Zhou 《Nanoscale research letters》2013,8(1):184
Thermochemical properties and microstructures of the composite of Al nanoparticles and NiO nanowires were characterized. The nanowires were synthesized using a hydrothermal method and were mixed with these nanoparticles by sonication. Electron microscopic images of these composites showed dispersed NiO nanowires decorated with Al nanoparticles. Thermal analysis suggests the influence of NiO mass ratio was insignificant with regard to the onset temperature of the observed thermite reaction, although energy release values changed dramatically with varying NiO ratios. Reaction products from the fuel-rich composites were found to include elemental Al and Ni, Al2O3, and AlNi. The production of the AlNi phase, confirmed by an ab initio molecular dynamics simulation, was associated with the formation of some metallic liquid spheres from the thermite reaction. 相似文献
57.
Ha Vu Thi Thu Nguyen Manh B. Tam Tran Nhu Thu Vu Thi Yen Pham Thi Hai Phong Pham Hong Nhiem Dao Ngoc Hung Le Quoc Hai Tran Quang 《Journal of Applied Electrochemistry》2022,52(3):607-616
Journal of Applied Electrochemistry - In this study, a sensitive and selective electrochemical sensor based on a zirconia oxide-decorated gold nanoflake nanocomposite-modified glassy carbon... 相似文献
58.
Methane aromatization over Mo/H-ZSM-5: on the reaction pathway 总被引:7,自引:0,他引:7
Rates of benzene formation on Mo/HZSM-5, H-ZSM-5 and Mo/SiO2 were measured with different reactants: methane, mixture of C2H4/H2/N2 and mixture of C2H2/H2/N2. Since the rate of benzene formation starting from C2H4/H2/N2 is higher on Mo/H-ZSM-5 compared to H-ZSM-5 it is concluded that the aromatization of methane on Mo/H-ZSM-5 is not going
via ethylene which is aromatized over acid sites. Another reaction pathway is proposed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
59.
Tran Thi Ngoc Lan Rokuro Nishimura Yukihiro Satoh Masayuki Yokoi 《Corrosion Science》2005,47(4):1023-1038
The atmospheric corrosion of marble was evaluated in terms of SO2 concentration as air pollution and climatic factors such as rainfall, relative humidity, temperature and so on under the field exposure. Marble of calcite type (CaCO3) was exposed to outdoor atmospheric environment with and without a rain shelter at four test sites in the southern part of Vietnam for 3-month, 1- and 2-year periods from July 2001 to September 2003. The thickness loss of marble was investigated gravimetrically. X-ray diffraction and X-ray fluorescent methods were applied to study corrosion products on marble. The corrosion product of marble was only gypsum (CaSO4 · 2H2O) and was washed out by rain under the unsheltered exposure condition. It was found that the most substantial factors influencing the corrosion of marble were rainfall, SO2 concentration in the air and relative humidity. Based on the results obtained, we estimated the dose-response functions for the atmospheric corrosion of marble in the southern part of Vietnam. 相似文献
60.
Ly Thi Thanh Le Lukasz Kotula Kadambot H. M. Siddique Timothy D. Colmer 《International journal of molecular sciences》2021,22(4)
Grain legumes are important crops, but they are salt sensitive. This research dissected the responses of four (sub)tropical grain legumes to ionic components (Na+ and/or Cl−) of salt stress. Soybean, mungbean, cowpea, and common bean were subjected to NaCl, Na+ salts (without Cl−), Cl− salts (without Na+), and a “high cation” negative control for 57 days. Growth, leaf gas exchange, and tissue ion concentrations were assessed at different growing stages. For soybean, NaCl and Na+ salts impaired seed dry mass (30% of control), more so than Cl− salts (60% of control). All treatments impaired mungbean growth, with NaCl and Cl− salt treatments affecting seed dry mass the most (2% of control). For cowpea, NaCl had the greatest adverse impact on seed dry mass (20% of control), while Na+ salts and Cl− salts had similar intermediate effects (~45% of control). For common bean, NaCl had the greatest adverse effect on seed dry mass (4% of control), while Na+ salts and Cl− salts impaired seed dry mass to a lesser extent (~45% of control). NaCl and Na+ salts (without Cl−) affected the photosynthesis (Pn) of soybean more than Cl− salts (without Na+) (50% of control), while the reverse was true for mungbean. Na+ salts (without Cl−), Cl− salts (without Na+), and NaCl had similar adverse effects on Pn of cowpea and common bean (~70% of control). In conclusion, salt sensitivity is predominantly determined by Na+ toxicity in soybean, Cl− toxicity in mungbean, and both Na+ and Cl− toxicity in cowpea and common bean. 相似文献