scholarly journals The Effects of Iron Rust on the Ageing of Woods and Their Derived Pulp Paper

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3483
Author(s):  
Wael A. A. Abo Elgat ◽  
Ayman S. Taha ◽  
Mohamed Z. M. Salem ◽  
Yahia G. D. Fares ◽  
Martin Böhm ◽  
...  
Keyword(s):  
Wood Species ◽  
Lignin Content ◽  
Chemical Properties ◽  
Biological Properties ◽  
Accelerated Ageing ◽  
Pulp Yield ◽  
Cellulose Content ◽  
Fungal Activity ◽  
Pulp Paper ◽  
And Chemical Properties

The accelerated ageing of wood in terms of heating or iron rusting has a potential effect on the physio-mechanical, chemical and biological properties of wood. The effects of accelerated ageing on the mechanical, physical and fungal activity properties of some wood materials (Schinus terebinthifolius, Erythrina humeana, Tectona grandis, Pinus rigida and Juglans nigra) were studied after several cycles of heating and iron rusting. The fungal activity was assayed against the growth of Aspergillus terreus, Aspergillus niger, Fusarium culmorum and Stemphylium solani. In addition, the mechanical and optical properties of paper sheets produced from those wood pulps by means of Kraft cooking were evaluated. The mechanical and chemical properties of the studied wood species were affected significantly (p < 0.05) by the accelerated ageing, compared to control woods. With Fourier transform infrared (FTIR) spectroscopy, we detected an increase in the intensity of the spectra of the functional groups of cellulose in the heated samples, which indicates an increase in cellulose content and decrease in lignin content, compared to other chemical compounds. For pulp properties, woods treated by heating showed a decrease in the pulp yield. The highest significant values of tensile strength were observed in pulp paper produced from untreated, heated and iron-rusted P. rigida wood and they were 69.66, 65.66 and 68.33 N·m/g, respectively; we calculated the tear resistance from pulp paper of untreated P. rigida (8.68 mN·m2/g) and T. grandis (7.83 mN·m2/g) and rusted P. rigida (7.56 mN·m2/g) wood; we obtained the values of the burst strength of the pulp paper of untreated woods of P. rigida (8.19 kPa·m2/g) and T. grandis (7.49 kPa·m2/g), as well as the fold number of the pulp paper of untreated, heated and rusted woods from P. rigida, with values of 195.66, 186.33 and 185.66, respectively. After 14 days from the incubation, no fungal inhibition zones were observed. Accelerated ageing (heated or iron-rusted) produced significant effects on the mechanical and chemical properties of the studied wood species and affected the properties of the produced pulp paper.

scholarly journals Variation of morphological and chemical properties of three varieties of jute stick

2016 ◽  
Vol 51 (4) ◽  
pp. 307-312 ◽  
Author(s):  
M Mostafizur Rahman ◽  
S Siddiqua ◽  
F Akter ◽  
M Sarwar Jahan ◽  
MA Quaiyyum
Keyword(s):  
Lignin Content ◽  
Chemical Constituents ◽  
Fibre Length ◽  
Chemical Properties ◽  
Morphological Characteristics ◽  
Pulp Yield ◽  
Cellulose Content ◽  
Middle Portion ◽  
Corchorus Capsularis ◽  
And Chemical Properties

Pulp property of a lignocellulosic material depends upon its morphological characteristics and chemical constituents it. Shabuj Pat (CVL-1) variety from Corchorus capsularis and BJRI Tossa Pat 4 (O-72) and BJRI Tossa Pat 5 (O-795) varieties from Corchorus olitorius of jute are mostly grown in Bangladesh. This study deals on morphological and chemical properties of these three varieties of jute stick to assess their suitability for pulp production. The results were significantly differed among the varieties and within the variety. The ?-cellulose content was almost the same in the variety of CVL-1 and O-795. In the same variety, the middle portion contained the largest amount of alpha-cellulose and the top portion contained the lowest. Klason lignin content varied from 24.2 to 26.8%. Fibre length was significantly same for all the three jute sticks but the width and slenderness ratios were different. Pulp yield in soda anthraquinone process was nearly the same in all these varieties around 44% at kappa number 15.Bangladesh J. Sci. Ind. Res. 51(4), 307-312, 2016

The Research on the Physical and Chemical Properties of Eggplant Stalk Fiber for the Complex Utilization of Stalk

2014 ◽  
Vol 881-883 ◽  
pp. 1161-1164
Author(s):  
Li Xia Li ◽  
Hai Tao Chen
Keyword(s):  
Lignin Content ◽  
Chemical Properties ◽  
Test Method ◽  
Chemical Compositions ◽  
Cellulose Content ◽  
Physical And Chemical Properties ◽  
Length Width ◽  
Complex Utilization ◽  
Physical And Chemical ◽  
And Chemical Properties

The physical and chemical properties of stalk fiber extracted by different method was important for the characters of the product. And the research laid the foundation for the complex utilization of eggplant stalk.Morphology of eggplant stalk fiber was determined by Feica microscope, the length, width and length to wide ratio were analyzed by SPSS 17.0. Chemical compositions different analysisof eggplant stalk fiber extracted by mechanical process were analyzed by applying Block test method with Design-expert 6.0.10.The result present that length, width, and length to wide ratio of stalk fiber were 11 mm,1338 um,20,respectively. Cellulose content of eggplant stalk was 34.31 %, hemi-cellulose content was 11.03%, lignin content was10.69 %.Cellulose content of eggplant stalk fiber was 36.2 %, hemi-cellulose content was18.55 %,lignin content was 17.49%.Hemi-cellulose increased by 7.52 %, cellulose increased by1.89 %, lignin increased by 6.8 %.The composition of fiber had significant difference.Beating degree was positively correlated with the beating time, beating time and wet weight were a negative correlation. Strength of stalk fiber was positively with the gramme, and strength was8.3N when gramme was 60 g/m2.

scholarly journals Structure Determination of C23H19N4OBr from Synchrotron Data

2014 ◽  
Vol 70 (a1) ◽  
pp. C141-C141
Author(s):  
Ozen Ozgen ◽  
Engin Kendi ◽  
Semra Koyunoglu ◽  
Akgul Yesilada ◽  
Hwo-Shuenn Sheu
Keyword(s):  
Powder Diffraction ◽  
Structural Information ◽  
Chemical Properties ◽  
Biological Properties ◽  
Cell Parameters ◽  
Fundamental Understanding ◽  
Physical And Chemical ◽  
Radiation Research ◽  
And Chemical Properties

A significant part of medicine is based on the discovery and development of drugs. It is very important to know the crystal structure of pharmaceutical compounds for fundamental understanding of structure, physical and chemical properties. Many of these materials are available only as powders. So any structural information must be obtained from powder diffraction. I am going to present following the stages while solving the structure of C23H19N4OBr, 2-[3-phenyl-4(m-bromophenyl)-2-pyrazolin-1-yl]-3-methyl-4(3H)-quinazolinone, from 2-pyrazolines derivatives. The compounds are known to display various biological properties such as fungicidal insecticidal, anti bacterial, anti viral activities, pharmacological properties such as antiinflammatory agents and have industral properties(1). The powder diffraction data was collected with Debye Scherrer camera at the BL01C2 beamline at room temperature in National Synchrotron Radiation Research Center(NSRRC), Taiwan. X-ray of wavelength was 1.0333Å. This compound crystallizes in orthorhombic system space group P bca, Z=8, unit cell parameters of a=25.83(1)Å, b=15.55(5)Å, c=10.63(3)Å, and V=4266.0(10)Å3. Reliability factors were reached Rwp=0.075, Rp=0.053, RB=0.086 ve S=1.31 after Rietveld refinement.

scholarly journals Insight into Erythrina Lectins: Properties, Structure and Proposed Physiological Significance

2017 ◽  
Vol 5 (1) ◽  
pp. 57-71 ◽  
Author(s):  
Makarim Elfadil M. Osman ◽  
Emadeldin Hassan E. Konozy
Keyword(s):  
Biological Significance ◽  
Chemical Properties ◽  
Biological Properties ◽  
Physical And Chemical Properties ◽  
Vegetative Tissues ◽  
Isolation And Characterization ◽  
Coral Tree ◽  
Physical And Chemical ◽  
Insight Into ◽  
And Chemical Properties

The genus Erythrina, collectively known as “coral tree”, are pantropical plants, comprising of more than 112 species. Since the early 1980s, seven of these have been found to possess hemagglutinating activity, although not yet characterized. However, around two dozen galactose-binding lectins have been isolated and fully characterized with respect to their sugar specificity, glycoconjugates agglutination, dependence of activity on metal ions, primary and secondary structures and stability. Three lectins have been fully sequenced and the crystal structures of the two proteins have been solved with and without the haptenic sugar. Lectins isolation and characterization from most of these species usually originated from the seeds, although the proteins from other vegetative tissues have also been reported. The main objective of this review is to summarize the physicochemical and biological properties of the reported purified Erythrina lectins to date. Structural comparisons, based on available lectins sequences, are also made to relate the intrinsic physical and chemical properties of these proteins. Particular attention is also given to the proposed biological significance of the lectins from the genus Erythrina.

scholarly journals A Comprehensive Characterization of Different Fractions of Corn Stover and Their Relationships to Multipollutant Sorption Characteristics

2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Dan Peng ◽  
Fan Ouyang ◽  
Min Deng ◽  
Lei Nie ◽  
Sifang Kong
Keyword(s):  
Adsorption Capacity ◽  
Corn Stover ◽  
Organic Pollutants ◽  
Lignin Content ◽  
Chemical Properties ◽  
Cellulose Content ◽  
Adsorption Effect ◽  
Adsorption Processes ◽  
Pseudo Second Order ◽  
Physical And Chemical

Corn stover (CS) is mainly composed of three parts: pith (CSP), rind (CSR), and leaf (CSL). These parts have different lignocellulosic constituents and structural properties. Herein, biosorbents derived from individual corn stover constituents were prepared in an effort to determine the significance of each constituent for multipollutant removal. In this study, SEM, BET, XRD, FTIR, XPS, fibre composition, and contact angle measurements were used to characterize and analyse the physical and chemical properties of the three components of CS and to study their adsorption effects, adsorption isotherms, and kinetics. The lignocellulosic compositions of CSP and CSR were similar, the cellulose content in CSP and CSR was significantly higher than that in CSL, and the hemicellulose content of CSL was much higher than those of CSP and CSR. The minimum lignin content was found in CSP, and the maximum lignin content was found in CSR. The results show that each component had a certain adsorption effect on typical organic pollutants (antibiotics, oils, and dyes). CSP had the strongest oil adsorption capacity, CSR was more suitable for adsorbing antibiotics, and CSL had outstanding adsorption capacity for dye. The pseudo-second-order model and the Langmuir adsorption isotherm model could describe the adsorption processes well, and they consisted of monolayer adsorption accompanied by chemical adsorption reactions. The focus of this study was to provide references for selecting effective adsorbent precursors to remove organic pollutants from wastewater.

scholarly journals The semisynthesis of analogues of cytochrome c. Modifications of arginine residues 38 and 91

1983 ◽  
Vol 215 (3) ◽  
pp. 651-658 ◽  
Author(s):  
C J A Wallace ◽  
K Rose
Keyword(s):  
Cytochrome C ◽  
Chemical Properties ◽  
Biological Properties ◽  
Adduct Formation ◽  
Eukaryotic Evolution ◽  
Functional Roles ◽  
Arginine Residues ◽  
Biological Tests ◽  
Horse Cytochrome ◽  
And Chemical Properties

The arginine residues at positions 38 and 91 of horse cytochrome c are absolutely conserved throughout eukaryotic evolution. For studies of the functional roles of these residues, we have prepared, by semisynthetic techniques, analogues of cytochrome c in which one or the other of the arginine residues has been modified. The products of modification by adduct formation with pentane-2,4-dione were purified and extensively characterized. In biological tests, the arginine-91-modified cytochrome c showed little difference in behaviour from native horse cytochrome c. Modification of arginine-38, however, led to extensive changes in biological and chemical properties. We also prepared and tested adducts with cyclohexane-1,2-dione and camphorquinone-10-sulphonic acid. The same effects on biological properties were noted irrespective of the nature of the modifying group. We suggest reasons for the differences in sensitivity of the two sites.

scholarly journals Physical and chemical properties of Castanopsis fargesii wood after heat treatment in sand or vacuum media

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 5821-5837
Author(s):  
Wen-Yu Qi ◽  
Cai Liu ◽  
Xiao-Lian Wu ◽  
Ji-Qing Li ◽  
Xin Guan ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Dimensional Stability ◽  
Color Change ◽  
Lignin Content ◽  
Chemical Properties ◽  
Dry Density ◽  
Physical And Chemical Properties ◽  
Castanopsis Fargesii ◽  
Physical And Chemical ◽  
And Chemical Properties

Castanopsis fargesii is among the most prevalent hardwood species in South China. To improve the poor dimensional stability of C. fargesii wood, heat treatments were performed using vacuum or sand as the medium at four temperatures from 170 °C to 215 °C for 4 h. As a medium, vacuum or sand can create a low oxygen environment. The results showed that, as the temperature increased, the oven-dry density decreased, whereas the dimensional stability and the total color change (∆E*) increased with both media, two different changing patterns of a* and b* were observed, the lignin content increased, and the holocellulose content decreased. The oven-dry density decreased 9.4% and 25.5%, volume shrinkage ratio decreased 27.8% and 37.7%, and the ∆E* was 19.63 and 45.52, the lignin contents increased from 17.62% to 28.62% and 42.87%, and the holocellulose contents decreased from 80.49% to 69.43% and 51.04% when C. fargesii wood was heated under vacuum and with sand at 215 °C, respectively. Overall, sand heat treatment affected wood physical and chemical properties more than vacuum heat treatment. The analysis of functional groups and crystallinity also showed that there were severe changes in C. fargesii wood under sand heat treatment.

Variation of surface and bonding properties among four wood species induced by a high voltage electrostatic field (HVEF)

Holzforschung ◽  
2019 ◽  
Vol 73 (10) ◽  
pp. 957-965 ◽  
Author(s):  
Qian He ◽  
Tianyi Zhan ◽  
Haiyang Zhang ◽  
Zehui Ju ◽  
Lu Hong ◽  
...  
Keyword(s):  
High Voltage ◽  
Electrostatic Field ◽  
Wood Species ◽  
Phenol Formaldehyde ◽  
Lignin Content ◽  
Chemical Properties ◽  
Pinus Massoniana ◽  
Populus Tomentosa ◽  
Chinese Fir ◽  
Masson Pine

Abstract A high voltage electrostatic field (HVEF) was applied to enhance the bonding performance of wood composites prepared with phenol-formaldehyde (PF) adhesive and different wood species and radial cut combinations. Four wood species including Masson pine (Pinus massoniana), Chinese fir (Cunninghamia lanceolata), poplar (Populus tomentosa) and ayous (Triplochiton scleroxylon) were studied. The results of HVEF-treatment turn out to be species-dependent, and are related to the anatomical and chemical properties of wood. It was demonstrated by a statistical approach that the lignin content is the most significant parameter with a good correlation coefficient (R2 > 0.8). High lignin content leads to high free radical concentration at the wood surface and the HVEF enhanced the adhesive penetration depth, the maximal density and the bonding strength (Bst) at the interphase. On the contrary, high extract contents and large lumina diameters negatively impacted the surface modification by HVEF. The magnitude of the effects was in the following order: ayous < poplar < Masson pine < Chinese fir.

scholarly journals Effects of Age and Height on Chemical Properties of Yushania Alpina Grown at Injibara District, Amhara Region, Ethiopia

2019 ◽  
Vol 4 (1) ◽  
pp. 32-36
Author(s):  
Amsalu Tolessa ◽  
Fikremariam Haile ◽  
Abraham Dilnesa ◽  
Buzayehu Desisa ◽  
Tegene Tantu ◽  
...  
Keyword(s):  
Lignin Content ◽  
Chemical Constituents ◽  
Chemical Properties ◽  
Industrial Sector ◽  
Chemical Components ◽  
Cellulose Content ◽  
Mean Values ◽  
Comprehensive Knowledge ◽  
American Society ◽  
Chemical Testing

This paper studied the chemical composition of cultivated 3, 4 and 5 year-old highland bamboo (Y. alpina) which were classified into three position (top, medium and bottom) to determined the main compositions especially cellulose, lignin, extractive and ash content. From all culms representative samples were converted to the required size of wood chips to prepared sample for chemical testing. Then the specimens prepared from bottom, middle and top portions for the three ages were used to determine the chemical properties in accordance to American Society for Testing and Materials (ASTM) standards except for cellulose test determined according to Kurschner and Hoffer method. All parameters in the experiment were expressed by percent based on dry basis. From this research, we have found small but significant increases in mean cellulose content from the base to the top of the culm at all three ages. The lignin content in Y. alpina species of bamboo is in the ranged of 23.04 to 30.03%. The mean values of the chemical constituents in 3, 4 and 5- year-old culms were 51.83, 54.94 and 49.78% for cellulose content, 28.28, 24.99 and 24.53% for lignin content, 7.8, 10.09, and 9.54% for alcohol-toluene extractive, respectively. In general, the comprehensive knowledge of the chemical components in the bamboo species will facilitate the use of the materials in the forestry industrial sector and help to enhance their utilization in the chemical and bio-chemical related industry.

Sign in / Sign up

Export Citation Format

Share Document