scholarly journals Changes in the Dimensions of Lignocellulose Nanofibrils with Different Lignin Contents by Enzymatic Hydrolysis

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2201
Author(s):  
Jae-Hyuk Jang ◽  
Noriko Hayashi ◽  
Song-Yi Han ◽  
Chan-Woo Park ◽  
Fauzi Febrianto ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Lignin Content ◽  
Crystallinity Index ◽  
Average Diameter ◽  
Cellulose I ◽  
Composition And Structure ◽  
Wide Range ◽  
Acetic Acid Treatment ◽  
Disk Mill ◽  
Lignocellulose Nanofibrils

Changes in the dimensions of lignocellulose nanofibrils (LCNFs) with different lignin contents from betung bamboo (Dendrocalamus asper) by enzymatic hydrolysis using endoglucanase (EG) were investigated. Lignin contents were adjusted from 3% to 27% by NaClO2/acetic acid treatment, and LCNFs were prepared using a wet disk-mill (WDM). The dimensions of the LCNFs significantly decreased with decreasing lignin content and increasing EG addition. With increasing EG content, the average diameter of the LCNFs significantly decreased, even though they contained parts of hemicellulose and lignin. The crystal structure showed the typical cellulose I structure in all samples, but the intensity of the diffraction peak slightly changed depending on the lignin and EG contents. The crystallinity index (CrI) values of the LCNFs increased a maximum of 23.8% (LCNF-L27) under increasing EG addition, regardless of the lignin content. With the EG addition of three times the LCNF amount, LCNF-L3 showed the highest CrI value (59.1%). By controlling the composition and structure of LCNFs, it is expected that the wide range of properties of these materials can extend the property range available for existing materials.

Effect of mercerization on the crystallite size and crystallinity index in cellulose from different sources

1987 ◽  
Vol 65 (8) ◽  
pp. 1724-1725 ◽  
Author(s):  
J. F. Revol ◽  
A. Dietrich ◽  
D. A. I. Goring
Keyword(s):  
Sodium Hydroxide ◽  
Crystallite Size ◽  
Narrow Range ◽  
Crystallinity Index ◽  
Cellulose Ii ◽  
Cellulose I ◽  
Native Cellulose ◽  
Wide Range ◽  
Different Sources ◽  
Low Crystallinity

Native cellulose samples having a wide range of crystallinity and crystallite size were mercerized by treatment with sodium hydroxide. The resultant cellulose II samples showed only a narrow range of crystallinity and an essentially constant crystallite size. For the low-crystallinity samples, crystallinity and crystallite size actually increased on mercerization. These results are in line with the proposal that mercerization involves the mingling of chains from adjacent and antiparallel cellulose I microfibrils to form cellulose II crystals of antiparallel chains.

scholarly journals Impact of Lignin Content on the Sweet Sorghum Bagasse Enzymatic Hydrolysis

2014 ◽  
Vol 61 ◽  
pp. 1957-1960
Author(s):  
Zhipei Yan ◽  
Jihong Li ◽  
Shizhong Li ◽  
Ting Cui ◽  
Yan Jiang ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Sweet Sorghum ◽  
Lignin Content ◽  
Sweet Sorghum Bagasse ◽  
Sorghum Bagasse

scholarly journals Effect of Subsequent Dilute Acid and Enzymatic Hydrolysis on Reducing Sugar Production from Sugarcane Bagasse and Spent Citronella Biomass

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Robinson Timung ◽  
Narendra Naik Deshavath ◽  
Vaibhav V. Goud ◽  
Venkata V. Dasu
Keyword(s):  
Enzymatic Hydrolysis ◽  
Sugarcane Bagasse ◽  
Crystallinity Index ◽  
Sem Analysis ◽  
Reducing Sugar ◽  
Dilute Acid Pretreatment ◽  
Crystalline Cellulose ◽  
Dilute Acid ◽  
Acid Pretreatment ◽  
Hydrolysis Of

This work was aimed at investigating the effect of process parameters on dilute acid pretreatment and enzymatic hydrolysis of spent citronella biomass (after citronella oil extraction) and sugarcane bagasse on total reducing sugar (TRS) yield. In acid pretreatment, the parameters studied were acid concentration, temperature, and time. At the optimized condition (0.1 M H2SO4, 120°C, and 120 min), maximum TRS obtained was 452.27 mg·g−1and 487.50 mg·g−1for bagasse and citronella, respectively. Enzymatic hydrolysis of the pretreated biomass usingTrichoderma reesei26291 showed maximum TRS yield of 226.99 mg·g−1for citronella and 282.85 mg·g−1for bagasse at 10 FPU, 50°C, and 48 hr. The maximum crystallinity index (CI) of bagasse and citronella after acid pretreatment obtained from X-ray diffraction analysis was 64.41% and 56.18%, respectively. Decreased CI after enzymatic hydrolysis process to 37.28% and 34.16% for bagasse and citronella, respectively, revealed effective conversion of crystalline cellulose to glucose. SEM analysis of the untreated and treated biomass revealed significant hydrolysis of holocellulose and disruption of lignin.

Research on Crystallinity, Morphology of Cotton Subjected to Enzyme and Crosslinking Treatment

2017 ◽  
Vol 893 ◽  
pp. 71-76 ◽  
Author(s):  
Md. Nahid Pervez ◽  
Faizan Shafiq ◽  
Muhammad Munib Jilani ◽  
Zahid Sarwar ◽  
Ying Jie Cai
Keyword(s):  
Crystalline Structure ◽  
Cotton Fiber ◽  
Crystallinity Index ◽  
Cotton Fibers ◽  
Cellulose I ◽  
X Ray ◽  
Cotton Fibres ◽  
Ft Ir ◽  
Crystalline Nature ◽  
Crosslinking Agents

This paper explores the effect of prior enzymatic treatment on non-formaldehyde crosslinked cotton fiber and crystalline structure of cotton fibers after enzyme, crosslinking and a combination of enzyme and crosslinking treatments were examined by X-ray diffractometer. Results showed that during crosslinking treatment crystallinity index (%) values were increased with reduced crystallinity size and crosslinked of enzyme treated cotton did not change the crystalline nature of cotton (i.e. it was Cellulose I). In addition, by analysing FT-IR and SEM data it is confirmed that uniform presence of crosslinking agents was visible on cotton fibres.

Synthesis of LiCoO2 particles with tunable sizes by a urea-based-homogeneous-precipitation method

2020 ◽  
Vol 111 (4) ◽  
pp. 347-355
Author(s):  
Munekazu Motoyama ◽  
Hiroki Iwasaki ◽  
Miyuki Sakakura ◽  
Takayuki Yamamoto ◽  
Yasutoshi Iriyama
Keyword(s):  
Size Distribution ◽  
Average Diameter ◽  
Precipitation Method ◽  
Homogeneous Precipitation ◽  
Uniform Size ◽  
Homogeneous Precipitation Method ◽  
Wide Range ◽  
Size Uniformity ◽  
Average Size ◽  
Uniform Size Distribution

Abstract This paper reports the synthesis of monodisperse spherical LiCoO2 particles in a wide range of average diameter using a urea-based-uniform-precipitation method. The average diameter of LiCoO2 particles can be varied from 2 to 14 lm with a uniform size distribution. The effective approach to maintain the size uniformity while changing the average size of LiCoO2 particles is to keep the ratio of [CO(NH2)2] to [CoSO4] at 8 even when the CoSO4 and urea concentrations are changed.

scholarly journals Investigation of a promising method for spraying liquid hydrocarbons using the shadow photography method

2019 ◽  
Vol 196 ◽  
pp. 00010 ◽  
Author(s):  
Igor Anufriev ◽  
Evgeniy Shadrin ◽  
Evgeniy Kopyev
Keyword(s):  
High Speed ◽  
Superheated Steam ◽  
Promising Method ◽  
Size Distributions ◽  
Liquid Hydrocarbons ◽  
Droplet Flow ◽  
Fuel Droplets ◽  
Composition And Structure ◽  
Wide Range ◽  
Photography Method

A promising method for spraying liquid hydrocarbons by a high-speed jet of superheated steam was studied experimentally. Information on the disperse composition and structure of the gas-droplet flow during the spraying of used transmission automotive oil was obtained using the method of shadow photography. Size distributions of fuel droplets were obtained in a wide range of operating parameters (flow rate and temperature of steam, fuel consumption).

scholarly journals EVALUATION OF ALKALINE PRETREATMENT ON THE ENZYMATIC HYDROLYSIS OF CARNAUBA STRAW RESIDUE

2019 ◽  
Vol 8 (3) ◽  
Author(s):  
Alan De Oliveira Campos ◽  
Francinaldo Leite Da Silva ◽  
Emilianny Rafaely Batista Magalhães ◽  
Gorete Ribeiro De Macedo ◽  
Everaldo Silvino Dos Santos
Keyword(s):  
Enzymatic Hydrolysis ◽  
Cellulosic Ethanol ◽  
Chemical Characterization ◽  
Crystallinity Index ◽  
Biomass Pretreatment ◽  
Cellulose Conversion ◽  
Hydrolysis Of ◽  
Potential Use ◽  
Second Generation Ethanol

Carnauba (Copernicia prunifera) straw residue generated from production of its wax is rich in cellulose, thus showing a potential use in the production of second generation ethanol. However, the high lignin and hemicellulose load associated with cellulose makes it difficult the enzymatic attack, thus having the need of an adequate pretreatment of this material. The objective of this study was to optimize the enzymatic hydrolysis of carnauba straw residue, focusing on the alkaline biomass pretreatment. Therefore, NaOH solutions at concentrations of 1.0% (w/v) (PA1), 2.0% (w/v) (PA2), 3.0% (w/v) (PA3) and 4.0% (w/v) (PA4) were used. The chemical and physical characterization of natural and pre-treated carnauba straw were according to the NREL, and DRX and FTIR performed analyzes. The materials chemical characterization showed that all the used pretreatments were able to remove a significant amount of lignin and hemicellulose, which can improve the enzymes access, favoring the increase of cellulose conversion. In relation to DRX analysis an increase in crystallinity index happens reaching up to 55.15% after the pretreatment PA4, which may be associated to the removal of hemicellulose and amorphous lignin, related to cellulose. After a period of 96 hours of enzymatic hydrolysis, the PA4 pretreated residue showed the best performance with a cellulosic conversion of 78%. Spite of a slightly lower performance of the residue that presented higher cellulose conversion, the pretreated material PA2 is an alternative to reduce costs in the cellulosic ethanol production.

scholarly journals Spinning Cellulose Hollow Fibers Using 1-Ethyl-3-methylimidazolium Acetate–Dimethylsulfoxide Co-Solvent

Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 972 ◽  
Author(s):  
Linfeng Lei ◽  
Arne Lindbråthen ◽  
Marius Sandru ◽  
Maria Gutierrez ◽  
Xiangping Zhang ◽  
...  
Keyword(s):  
Hollow Fiber ◽  
Average Diameter ◽  
Hollow Fibers ◽  
Cellulose Ii ◽  
Cellulose I ◽  
Structure Transition ◽  
Carbon Membranes ◽  
Ftir Characterization ◽  
Dope Solution ◽  
Mild Temperature

The mixture of the ionic liquid 1-ethyl-3-methylimidazolium acetate (EmimAc) and dimethylsulfoxide (DMSO) was employed to dissolve microcrystalline cellulose (MCC). A 10 wt % cellulose dope solution was prepared for spinning cellulose hollow fibers (CHFs) under a mild temperature of 50 °C by a dry–wet spinning method. The defect-free CHFs were obtained with an average diameter and thickness of 270 and 38 µm, respectively. Both the XRD and FTIR characterization confirmed that a crystalline structure transition from cellulose I (MCC) to cellulose II (regenerated CHFs) occurred during the cellulose dissolution in ionic liquids and spinning processes. The thermogravimetric analysis (TGA) indicated that regenerated CHFs presented a similar pyrolysis behavior with deacetylated cellulose acetate during pyrolysis process. This study provided a suitable way to directly fabricate hollow fiber carbon membranes using cellulose hollow fiber precursors spun from cellulose/(EmimAc + DMSO)/H2O ternary system.

Part III Headquarters Agreements, 35 Legal Issues Related to International Military Headquarters

2018 ◽  
Author(s):  
Hill Steven ◽  
Favuzza Federica
Keyword(s):  
Economies Of Scale ◽  
Resource Constraints ◽  
Legal Issues ◽  
The Other ◽  
General Overview ◽  
Composition And Structure ◽  
Wide Range ◽  
Legal Nature ◽  
The Common ◽  
Contemporary Practice

This chapter provides a general overview of the types of international military headquarters (IMHQs) and their legal nature. IMHQs encompass a wide range of structures that are in use in the contemporary practice of States and international organifzations. States tend to find them attractive options for a variety of reasons, including the promotion of cooperation and coordination and the expression of shared political and/or military commitments. They can also be an important tool to help States address resource constraints, including by taking advantage of efficiencies gained through specialization and economies of scale. IMHQs all share the common characteristic of being in one way or the other ‘international’. Their nature varies widely, including with respect to their mission and their composition and structure. Because of this diversity, the chapter only discusses selected legal issues that tend to arise in connection with IMHQ and will likely arise in the future.

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