Synthesis of lignin nanoparticles employing acid precipitation method and its application to enhance the mechanical, UV-barrier and antioxidant properties of chitosan films

Author(s):  
Ramya Vijayakumar ◽  
Yamini Sivaraman ◽  
Keshava Murthy Pavagada Siddappa ◽  
Jeevan Prasad Reddy Dandu
2016 ◽  
Vol 864 ◽  
pp. 112-116
Author(s):  
Rinlee Butch M. Cervera ◽  
Emie A. Salamangkit-Mirasol

Rice hull or rice husk (RH) is an agricultural waste obtained from milling rice grains. Since RH has no commercial value and is difficult to use in agriculture, its volume is often reduced through open field burning which is an environmental hazard. In this study, amorphous nanosilica from Philippine waste RH was prepared via acid precipitation method. The synthesized samples were fully characterized for its microstructural properties. X-ray diffraction pattern reveals that the structure of the prepared sample is amorphous in nature while Fourier transform infrared spectrum showed the different vibration bands of the synthesized sample. Scanning electron microscopy (SEM) and particle size analysis (PSA) confirmed the presence of agglomerated silica particles. On the other hand, transmission electron microscopy (TEM) revealed an amorphous sample with grain sizes of about 5 to 20 nanometer range and has about 95 % purity according to EDS analyses. The elemental mapping also suggests that leaching of rice hull ash effectively removed the metallic impurity such as potassium element in the material. Hence, amorphous nanosilica was successfully prepared via a low-cost acid precipitation method from Philippine waste rice hull.


2022 ◽  
Vol 31 ◽  
pp. 100792
Author(s):  
Wei Zhang ◽  
Qixing Jiang ◽  
Jiandong Shen ◽  
Pei Gao ◽  
Dawei Yu ◽  
...  

1994 ◽  
Vol 57 (11) ◽  
pp. 996-1000 ◽  
Author(s):  
NOURREDINE BOUCHRITI ◽  
SAGAR M. GOYAL ◽  
ABDELHAK El MARRAKCHI ◽  
MOHAMMED JELLAL

Three methods were evaluated for the concentration of poliovirus from artificially contaminated oysters (Crassostrea gigas), mussels (Mytilus edulis) and carpet-shell clams (Ruditapes decussatus) grown in Morocco. The methods tested were: an adsorption-elution-precipitation method, a beef extract elution acid-precipitation method, and a non-fat dry milk elution acid-precipitation method. For all shellfish species tested, the adsorption-elution-precipitation method yielded the lowest average virus recovery (27%), whereas the two elution-precipitation methods yielded average virus recoveries of 42% each. The beef extract elution acid-precipitation method yielded the highest virus recovery with clams (53%), whereas non-fat dry milk elution acid-precipitation was advantageous for mussels providing average virus recovery of 47%. For oysters, none of the tested methods gave satisfactory virus recovery. These results point towards the need for the development of better method(s) for the concentration of viruses from Moroccan oysters, while for mussels and clams, the elution-acid precipitation methods may be satisfactory.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Li-Tong Ma ◽  
Ya-Nan Lu ◽  
Ya-Xiong Wang

The effects of acid precipitation with different liquid acids on spectral properties of fulvic acid extracted from peat was studied to select the most appropriate liquid acid for the acid precipitation step of the alkali solution acid precipitation method, and the new process mechanism of peat utilization by coupling methane fermentation and extraction of fulvic acid was analyzed. The alkali solution acid precipitation method was adopted to extract fulvic acid from the methane-fermented group and methane-unfermented group. Different liquid acids were used to conduct acid precipitation during the extraction. And then, the characterizations of fulvic acid samples were conducted through Fourier infrared spectroscopy, UV-Vis spectroscopy, and fluorescence spectroscopy. The yield and content of fulvic acid decreased significantly after methane fermentation. During the methane fermentation process, some fulvic acid was consumed and utilized by microorganisms to promote the methane fermentation process, resulting both in the decrease of methyl, hydroxyl, and ether bonds and in the increase of methylene, carbonyl, conjugated double bond, benzene rings, and other groups. The E4/E6 ratio shows that the E4/E6 ratio of fulvic acid was decreased after methane fermentation, and the fermentation consumed the functional group with simpler structure such as aliphatic chain hydrocarbon of fulvic acid while the structure with a higher degree of aromatization and conjugate cannot be consumed. When conducting acid precipitation with different liquid acids, the yield of fulvic acid was the highest through acid precipitation with phosphoric acid. The fulvic acid obtained through acid precipitation with nitric acid has a higher content, more benzene rings, and the highest degree of aromatization.


2017 ◽  
Vol 47 ◽  
pp. 236-245 ◽  
Author(s):  
Murat Kaya ◽  
Lalehan Akyuz ◽  
Idris Sargin ◽  
Muhammad Mujtaba ◽  
Asier M. Salaberria ◽  
...  

2015 ◽  
Vol 645-646 ◽  
pp. 145-150 ◽  
Author(s):  
Ai Qin Wang ◽  
Hui Hui Han ◽  
Min Li ◽  
Jing Pei Xie ◽  
Qing Jie Wu ◽  
...  

The YBCO powder was prepared by oxalic acid precipitation method and consequent annealing. The correlation between pH values of oxalic acid solution and the precipitation percentage of precursors were analysed based on thermodynamics analysis. The differential scanning calorimetryanalysis (DSC) was used to confirm the synthetic technological parameter. The phases of powder in each process were investigated by XRD. The microstructures of each powder were tested by SEM and TEM. The mean grain size was calculated by the scherrer’s equation. The test results indicated that the YBCO powder with high purity, less impurities, smaller particle, but severe agglomeration, was Y123 when annealing at 900°C. However, adding dispersants could effectively solve the severe agglomeration. The size of YBCO particles was nanosized and coincided with the calculation.


2017 ◽  
Vol 71 ◽  
pp. 176-186 ◽  
Author(s):  
Jun Liu ◽  
Shuang Liu ◽  
Yao Chen ◽  
Liang Zhang ◽  
Juan Kan ◽  
...  

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