scholarly journals Plastic composites made from glycerol, citric acid, and forest components

BioResources ◽  
2018 ◽  
Vol 13 (3) ◽  
pp. 6600-6612
Author(s):  
Rasika L. Kudahettige-Nilsson ◽  
Henrik Ullsten ◽  
Gunnar Henriksson
Keyword(s):  
Citric Acid ◽  
Maximum Stress ◽  
Plastic Material ◽  
Ash Content ◽  
Wood Powder ◽  
Renewable Materials ◽  
Amorphous Cellulose ◽  
Mechanical Pulp ◽  
3D Printers ◽  
Absorption Level

An ecofriendly approach for the synthesis of plastic biomaterials based on renewable materials suitable for 3D printing application or other applications has been developed. The material was prepared from native (microcrystalline) or amorphous cellulose, citric acid, and glycerol or ethylene glycol, by a pretreatment at 40 °C and a curing at 175 °C for 1 h. The results showed that tensile properties and the water absorption level of the material were acceptable. The highest strain at break (14%) was obtained from materials made of 10% amorphous cellulose with 90% glycerol/citric acid. It had a maximum stress at 37 MPa. Moreover, materials were without ash content. Possible applications of the material in 3D-printers were discussed. In addition, application of mechanical pulp and wood powder into novel plastic material production was discussed. Foaming during curing might be a problem for this type of material, but this can be avoided by using amorphous cellulose in the recipe.

scholarly journals A Novel Hydrogel Based on Renewable Materials for Agricultural Application

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Silvie Durpekova ◽  
Kateryna Filatova ◽  
Jaroslav Cisar ◽  
Alena Ronzova ◽  
Erika Kutalkova ◽  
...  
Keyword(s):  
Citric Acid ◽  
Water Uptake ◽  
Agricultural Product ◽  
Cellulose Derivatives ◽  
Gravimetric Analysis ◽  
Renewable Materials ◽  
Swelling Properties ◽  
Arable Farming ◽  
Swelling Capacity ◽  
The Stability

This study details the design and characterization of a new, biodegradable, and renewable whey/cellulose-based hydrogel (i.e., agricultural hydrogel). This was formulated from cellulose derivatives (carboxymethylcellulose (CMC) and hydroxyethylcellulose (HEC)) and acid whey cross-linked with citric acid, with the aim to obtain an agricultural product with a high swelling capacity to uphold the quality of soil and conserve water resources. With regard to the swelling behaviour of the prepared hydrogels, the authors initially assessed the swelling ratio and capacity for water uptake. Evaluating the chemical structure of the hydrogel and its thermal and viscoelastic properties involved performing Fourier transform infrared spectroscopy, differential scanning colorimetry, thermal gravimetric analysis, and rheological measurement of the hydrogel films. According to preliminary results, sufficient swelling capacity and stiffness were observed in a hydrogel prepared with 3% CMC and HEC, cross-linked with 5% citric acid. Moreover, the kinetics of water uptake revealed a promising capacity that was sustainable after 5 drying and swelling cycles. The results confirmed that the stability of the hydrogel was enhanced by the presence of the citric acid. As a consequence, it is necessary to utilize an appropriate cross-linking concentration and abide by certain conditions to ensure the swelling properties of the prepared hydrogel are sufficient. Further investigation of the topic, especially in relation to applications in soil, could confirm if the whey-cellulose-based hydrogel is actually suitable for agricultural use, thereby contributing to the advancement of sustainable arable farming.

scholarly journals Wet extrusion molding of wood powder with hydroxy-propylmethyl cellulose and with citric acid as a crosslinking agent

BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 2314-2325
Author(s):  
Xiangyu Tao ◽  
Hiroshi Nonaka
Keyword(s):  
Citric Acid ◽  
Crosslinking Agent ◽  
Three Dimensional ◽  
Heating Time ◽  
Wood Powder ◽  
Molding Process ◽  
Natural Substances ◽  
Biomass Materials ◽  
Wet Extrusion ◽  
Derivatives Of

To mitigate global warming and the serious problems incurred by the disposal of petroleum-based plastics, it is important to develop derivatives of biomass materials that can be used as substitutes. To overcome the lack of thermoplasticity of wood, a wet extrusion molding process for wood powder using a cellulose derivative, hydroxypropylmethyl cellulose (HPMC), had been developed. However, this material quickly reabsorbed water, swelled, and disintegrated in liquid. In the present study, a natural organic acid, citric acid, was added and kneaded together with the wood powder, the HPMC, and water. The resultant clay-like material was extruded into a tube-shaped material. The tube was air-dried and heated at 180 °C for 5 min to 30 min to allow crosslinking. By heating 1% citric acid for 30 min, the material avoided disintegrating in water for 60 min. The addition of 3% citric acid with 30 min crosslinking gave the material water resistance in water for 12 h. The degradability in the water was found to be controllable by changing the amount of citric acid and the heating time. This is a novel result because wood can be molded into a practical three-dimensional (3D) biomass composite material using this technology with natural substances without relying on petroleum-based plastics.

Dynamic Stresses During Structural Impacts

2003 ◽  
Author(s):  
Robert A. Leishear ◽  
Jeffrey H. Morehouse
Keyword(s):  
Maximum Stress ◽  
Plastic Material ◽  
Material Behavior ◽  
Solution Technique ◽  
Dynamic Stresses ◽  
Conservation Of Energy ◽  
Linear Elastic ◽  
Bending Stresses ◽  
Structural Impacts ◽  
Energy Principles

Dynamic stresses that occur when an object strikes a structure can be described by considering both vibration theory and conservation of energy principles. An object striking a simple beam is used as one of several examples. The complete stresses are found by adding the stresses obtained from a vibration equation to the stresses found by using a conservation of energy equation. When combined, these two stresses establish the maximum stress in a structure subject to impact. This solution assumes that each point within the beam acts as a linear system, reacting to the dynamic application of a load to the structure. When struck, the surface of the beam is momentarily compressed, and the beam bends. The equations describe both the localized stresses at the point of impact and the bending stresses in the beam following impact. These equations are then extended to an elastoplastic case, using a bilinear model to describe the dual natured linear elastic and linear plastic material behavior. The general solution technique is applicable to cases other than the simple beam.

scholarly journals Effect of Power and Time in Pectin Production from Cocoa Pod Husk Using Microwave-Assisted Extraction Technique

2020 ◽  
Vol 9 (1) ◽  
pp. 125-130
Author(s):  
Maya Sarah ◽  
Hisham Hisham ◽  
Mushila Rizki ◽  
Ricka Erwinda
Keyword(s):  
Citric Acid ◽  
Hydrochloric Acid ◽  
Ash Content ◽  
Microwave Assisted Extraction ◽  
Equivalent Weight ◽  
Microwave Assisted ◽  
Yield And Quality ◽  
Assisted Extraction ◽  
Cocoa Pod Husk

Investigation on microwave technique to extract pectin from cocoa pod husk in this study carries out using citric acid and hydrochloric acid (HCl). Extraction proceeds at various microwave powers (180, 300, 450, 600 Watt) and irradiation periods (10, 15, 20, 25, 30 minutes). This study observed effect of power and time to yield and quality of pectin.  Yield of pectin increased at elevated power and time either with citric acid or HCl solvent. Overall pectin quality in this study meet the IPPA quality factor exclude water content which relatively higher. MAE treatment with citric acid using microwave power of 300 Watt for 30 minutes resulted yield of 42% and high pectin quality as compare to MAE treatment with HCl. The best pectin product in this study has moisture content of 8%, ash content of 10%, equivalent weight of 714.29 mg, methoxyl content of 4.8% and galacturonate level of 43%. ©2020. CBIORE-IJRED. All rights reserved

Wood Powder Used in Paper Making to Improve Bulkness

2012 ◽  
Vol 550-553 ◽  
pp. 3352-3355
Author(s):  
Dong Mei Yu ◽  
Chuan Shan Zhao ◽  
Chao Jun Wu ◽  
Dai Qi Wang
Keyword(s):  
Wood Powder ◽  
Mechanical Pulp ◽  
Paper Making ◽  
Strength Enhancement

In this paper, we studied the possibility of wood powder in place of mechanical pulp in paper making to get high bulkness, also the dry-bleaching method of wood powder, the strength enhancement and retention effect for wood powder during paper making were all introduced and analyzed in detail.

Effect of soaking conditions on properties of flour from sweet potato slices

2021 ◽  
Vol 16 (3) ◽  
pp. 8-14
Author(s):  
Rahman Akinoso ◽  
Oluyemi Elizabeth Odusoga ◽  
Abdulquadri Alaka
Keyword(s):  
Citric Acid ◽  
Sweet Potato ◽  
Industrial Applications ◽  
Pasting Properties ◽  
Ash Content ◽  
Hot Water ◽  
Potato Root ◽  
Standard Procedures ◽  
Flour Properties ◽  
Potato Slices

Native flour of sweet potato has limited industrial applications. This study investigated effect of soaking sweet potato root in hot water and citric acid concentrations on flour properties. Sweet potato root was soaked at temperatures of 50oC, 60oC and 70oC for 2 h; citric acid concentrations of 1%, 3% and 5% for 1 h, and combination of best samples in each of the first two modification treatments in 50:50 proportions. Treated root was processed into flour using standard procedures. Proximate, functional and pasting properties of the flours were determined using standard methods. The flour was used as major ingredient in production of baked snacks. Treatments had significant effect on proximate, functional and pasting properties of the flour. Moisture content ranged from 6.5 to 9.7%, protein content 1.6 to 3.0%, ash content 0.1 to 3.15%, fiber content 3.6 to 4.2%, and carbohydrate content 82.1 to 84.7%. Water and oil absorption capacities ranged from 2.2 to 3.0 ml/g and 0.8 g/ml to 1.8 g/ml respectively, swelling power (4.32 to 9.23 g/g) and bulk density (0.77 to 0.95 g/ml). Snack produced with flour gotten from 60oC soaked root for 2 h was best in sensory ratings.

scholarly journals Karakteristik Fisikokimia dan Sensoris Selai Bengkuang (Pachyrhizus Erosus L.) dengan Penambahan Pektin dan Asam Sitrat pada Berbagai Konsentrasi

2021 ◽  
Vol 2 ◽  
pp. 77-83
Author(s):  
Arif Prashadi Santosa ◽  
Oetami Dwi Hajoeningtijas ◽  
Ismi Noviandita
Keyword(s):  
Citric Acid ◽  
Water Content ◽  
Proximate Analysis ◽  
Ash Content ◽  
Fiber Content ◽  
Color Preference ◽  
Physical Parameters ◽  
Citric Acid Concentration ◽  
Sensory Test ◽  
Crude Fiber Content

This research aimed to figure out the effect of differences in concentration of citric acidand pectin and their interactions on the content of proximate and sensory of jam.The research was conducted using a completely randomized design (CRD) with a factorial pattern consisting of two factors.The first factor was the comparison of thethree levels of citric acid (A) concentration:1% (A1), 2% (A2),and 3% (A3) of the total ingredients for making jam.The second factor was pectin concentration (P) in 4 levels: 0.83%(P1), 1.0% (P2), 1.17% (P3), and 1.34% (P4) of the total ingredients for making jam.The chemical parameters tested included moisture content, fiber content, ash content, and antioxidant, while the physical parameters included pH and viscosity.The sensory test assessments includedaroma, taste, color, preference, and spreadability.The results indicated that the comparison of the concentration of citric acid (A) had a significant effect on the proximate analysis of the pH variable; however, it had no significant effect on several other variables:moisture content, crude fiber content, ash content, viscosity, and antioxidant.The results of the sensory test did not significantly affect the variables of aroma, taste, color, preference, and spreadability.In addition, the treatment of pectin (P)concentration ratio had a significant effect toward proximate analysis on water content and viscosity variable, but it had no significant effect on the variables offiber content, ash content, pH, and antioxidant.Meanwhile, the sensory test had a significant effect on the preference variable and had no significant effect on the aroma, taste, color, and spreadibilityvariables.The treatment interactions (AxP) significantly affectedproximate analysis on pH and viscosity variables.However, it did not affect the variable of water content, fiber content, ash content, and antioxidantsignificantly.The sensory test results hada significant effect onpreference variable.The best treatment wason the use of 1% citric acid concentration and 0.83% pectin concentration (A1P1) with 42.63% water content, 37.54% fiber content, 0.25% ash content, pH of 3.30, a viscosity of 8.49 cP, and an antioxidant of 9.22%.The treatment resulted in the aroma of 3.67 (delicious), taste of 4.67 (delicious), color of 4.00 (yellowish white), preference of 5.00 (likevery much), and spreadability 3.67 (easy). 

scholarly journals Circular Tube Forming by Using Extrusion of Wood Powder Combined with Sucrose and Citric Acid

2021 ◽  
Vol 70 (12) ◽  
pp. 912-917
Author(s):  
Yuya SUZUMOTO ◽  
Shohei KAJIKAWA ◽  
Takashi KUBOKI
Keyword(s):  
Citric Acid ◽  
Circular Tube ◽  
Wood Powder ◽  
Tube Forming

scholarly journals Design and Analysis of a Dynamic Splint Based on Pulley Rotation for Post-Stroke Finger Extension Rehabilitation Device

2020 ◽  
Vol 11 (3) ◽  
pp. 477-485
Author(s):  
Zakki Fuadi Emzain ◽  
◽  
Shyh-Chour Huang ◽  
Yu-Sheng Yang ◽  
Nanang Qosim ◽  
...  
Keyword(s):  
Strain Energy ◽  
Maximum Stress ◽  
The Finite Element Method ◽  
Muscle Disorders ◽  
Finger Extension ◽  
Dynamic Splint ◽  
3D Printers ◽  
Hand Muscle ◽  
Deformation Stress ◽  
Future Work

The presence of rehabilitation tools is essential to more rapidly cure hand muscle disorders of people affected by stroke. One of the tools is a dynamic splint that is fit-sized, lightweight, comfortable to wear, and easy to operate. The paper proposes the design and analysis of new dynamic splints based on pulley rotation as a rehabilitation device for finger extension after stroke. This device consists of the main splint, the pulley, the locker, the finger handles, the ball bearing, and the fishing line. To lock and stop pulley turning, the locking system is designed to complement it which is also the most important mechanical segment. The shear stress of the pulley was 0.026 N/mm2. The deformation, stress, and strain energy of the locking system section were analyzed by the finite element method. The results showed that the deformation distribution around the locker section was at 0.1-0.15 mm intervals. The maximum stress 25.0786 MPa, which is still inferior to the yield strength of ABS Material (28.5 MPa). The safety factor of the structure is about n = 1.14. The largest strain energy was 0.2856 mJ at the same place as with the maximum stress which was close to the conical end of the locker. The correlation between stress-strain energy and moment was linear as well. In future work, a prototype will be fabricated using 3D printers, and it will be applied to the stroke patient. In addition, the therapies will be involved to assess the improvement of the finger extension of stroke patients.

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