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91.
With the fast development of microalgal biofuel researches, the proteomics studies of microalgae increased quickly. A filter-aided sample preparation (FASP) method is widely used proteomics sample preparation method since 2009. Here, a method of microalgae proteomics analysis based on modified filter-aided sample preparation (mFASP) was described to meet the characteristics of microalgae cells and eliminate the error caused by over-alkylation. Using Chlamydomonas reinhardtii as the model, the prepared sample was tested by standard LC-MS/MS and compared with the previous reports. The results showed mFASP is suitable for most of occasions of microalgae proteomics studies.  相似文献   
92.
In this study, efficient decomposition and debromination of monobromoacetic acid (MBAA) induced by radio frequency discharge in an aqueous solution in the concentration range from 0.1 to 8.0 mM were investigated. The decomposition and debromination intermediate byproducts were analyzed by ion chromatography. The experimental results showed that the decay of MBAA followed first-order kinetics. Increasing pH and adding organic additives to the solution enhanced MBAA removal and debromination. Acetic acid, bromate ion, oxalic acid and formic acid were determined as the major intermediate byproducts. Final products were bromide ion and carbon dioxide. Hydrated electrons are the primary species for the debromination and reactive oxygen species are the ones for the decomposition. A probable reaction pathway was proposed. The present study may provide a promising alternative for the complete mineralization of MBAA.  相似文献   
93.
94.
Several novel fused heterocyclic systems which have rings containing N/O or N/S have been synthesized through a facile one-pot method by the treatment of substituted 2-(benzo[d]thiazol-2-yl)phenol and cyanogen bromide in THF and NEt3. This one-pot method contains tough ring-opening of thiazole, special intermolecular rearrangement and ring-closing reactions. The newly synthesized compounds were characterized by HR-MS, 1H-NMR, 13C-NMR spectral data and DFT calculation analysis. 2a was also determined by X-ray crystallographic analysis.  相似文献   
95.
This study aimed to improve the stability of nanofibrillated cellulose (NFC) in an electrolyte containing system, which was achieved by the grafting of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) via the ceric ammonium nitrate-induced polymerization process. The results indicated that upon grafting the salt resistance and thermal stability of NFC were significantly improved. Moreover, the stability of the modified NFC increased with the AMPS loading. Compared to the control (the original NFC), the poly-AMPS/NFC (357.5 mg/g AMPS) exhibited much improved stability in a 400 mmol/L NaCl solution, and its viscosity was 350 mPa s. The thermogravimetric analysis results showed that the initial decomposition temperature of the modified NFC increased from 265 to 330 °C. Transmission electron microscopy (TEM) observations showed that the main morphologic features of NFC were not altered, suggesting that the grafting reaction occurred on the fiber surface. The modified NFC can have promising industrial applications, such as oil recovery.  相似文献   
96.
Zheng  Xiu-Cheng  Li  Ning  Wu  Min  Guan  Xin-Xin  Zhang  Xiao-Li 《Research on Chemical Intermediates》2017,43(11):6651-6664
Research on Chemical Intermediates - Reduced graphene oxide (rGO) was synthesized by chemical reduction of graphene oxide with hydrazine hydrate and used as supports to prepare a series of...  相似文献   
97.
Crosslinked poly(vinyl alcohol) (PVA)/cellulose nanofibril (CNF) hybrid aerogel micro-spheres with two different particle sizes were fabricated via a combination of the water-in-oil (W/O) emulsification process and the freeze-drying process. The aerogel micro-spheres were highly porous with a bulk density as low as 0.0047 g/cm3 for the large microspheres. The pore size of the microspheres ranged from nano- to micro-meters. Preliminary biocompatibility assays of the aerogel microspheres were investigated with NIH 3T3 cells to explore their potential application as cell culture scaffolds. The highly crosslinked aerogel microspheres were robust and were able to maintain their shape during the cell culture process. The live/dead assay showed that the cells could be seeded, attached, and proliferated on the surface of PVA/CNF aerogel microspheres. The fluorescence images showed that some of the cells migrated into the inner pores of the microspheres. Moreover, the large microspheres with larger average pore sizes had a higher cell count than that of the small microspheres. This study confirms that the PVA/CNF aerogel microspheres fabricated in this work are nontoxic and biocompatible. Furthermore, the interconnected, highly porous nanofibrous structure of the microspheres can successfully facilitate cell attachment, differentiation, and proliferation.  相似文献   
98.
In this work, cellulose–Ag@AgCl composite films have been fabricated directly through a one-step coagulation of a cellulose/1-butyl-3-methylimidazolium chloride (BmimCl) solution with AgNO3 and PVP. The AgCl was formed upon the addition of AgNO3 to a cellulose/BmimCl solution, and underwent further reaction with excess Cl?, leading to the complete dissolution of AgCl. The AgCl crystals were regenerated on the cellulose matrix during the coagulation process. The AgCl was partial decomposed to Ag0 and formed Ag@AgCl under visible light irradiation. The morphology of Ag@AgCl in the cellulose matrix was controlled by varying the concentration of PVP. The addition of PVP enabled the formation of stable cellulose films embedded with Ag@AgCl. The composite film demonstrated efficient photodegradation of methyl orange, which was retained upon recycling. This work thus provides a simple pathway for the preparation of Ag@AgCl embedded on a polymer support via one-step coagulation.  相似文献   
99.
以碳纤维(CF)为填料,聚偏氟乙烯(PVDF)为基体,通过熔融共混法制备PVDF/CF导电复合材料.所得复合材料具有显著的正温度系数(PTC)效应,温度上升到聚合物熔点附近时,电阻率对温度变化敏感.在转折温度区间(155.5~171.0oC,(35)(28)15.5oC)内,其体积电阻率的增加速率约为1.3×105?cm K-1.在不同CF含量下,复合材料表现出不同的PTC行为.随着CF含量的增加,其峰值电阻略有下降.高导电粒子含量下,无负温度系数(NTC)效应.在冷却循环过程,导电网络的重构性良好.复合材料即使经过多次热循环,依然表现出良好的PTC特性重现性.  相似文献   
100.
In this paper, a new price is given to the online decision maker at the beginning of each day. The trader must decide how many items to purchase according to the current price. We present three variants and an online algorithm based on cost function. The competitive ratio of the online algorithm is given for each variant, which is a performance measure of an online algorithm. More importantly, we show that the online algorithm is optimal.  相似文献   
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