scholarly journals Effect of the alkaline treatment conditions on the tableting performance of chitin obtained from shrimp heads

2014 ◽  
Vol 8 (7) ◽  
pp. 211-219 ◽  
Author(s):  
Rojas John ◽  
Hernandez Christian ◽  
Trujillo Diana
Keyword(s):  
Alkaline Treatment ◽  
Treatment Conditions ◽  
Shrimp Heads ◽  
Tableting Performance

scholarly journals Increased Comfort of Polyester Fabrics

Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 3010
Author(s):  
Meritxell Martí ◽  
Jaime Gisbert-Paya ◽  
Mª Ángeles Bonet-Aracil ◽  
Petar Jovančić ◽  
Manuel J. Lis ◽  
...  
Keyword(s):  
Water Vapor ◽  
Moisture Content ◽  
Microwave Irradiation ◽  
Alkaline Treatment ◽  
Negative Ion ◽  
Experimental Conditions ◽  
Hygroscopic Properties ◽  
Treatment Conditions ◽  
Moisture Increase ◽  
Subsequent Improvement

The hydrophilicity of fibers is directly related to the comfort of a fabric and represents one of the most important aspects of a textile. Therefore, polyester (PES) modification has focused on an increase in moisture content and a subsequent improvement of the user’s experience. Based on the glycerol hygroscopic properties, the main objective has been the enhancement of the hydrophilicity of polyester by glycerol treatments. Furthermore, microwave irradiation and alkaline treatment have been applied, in order to increase glycerol adhesion. Treated PES samples were characterized by performing moisture content, negative ion, water diffusion and water vapor resistance analyses. The effect of different treatment conditions such as bath ratio (1/10 or 1/15), temperature (40, 60 or 100 °C), time (2 or 5 min) and microwave radiation intensity (300 or 500 W) was evaluated. The moisture content of treated PES results indicated that by decreasing the bath ratio and increasing the time and temperature the moisture gain can reach almost 14%, which can be easily related to increases in the weight of the fiber. The treatment with alkali was done and led to the highest moisture increase. Treatment with 500 W microwave irradiation led to higher glycerol retention after rinsing. Different experimental conditions were applied to the glycerol-treated PES fabrics, and a clear improvement in moisture content was obtained increasing the comfort. The results were compared with the ones obtained for cotton and wool, where the moisture is higher than non treated PES.

Optimization of Alkaline Treatment Conditions of Flax Fiber Using Box–Behnken Method

2012 ◽  
Vol 9 (4) ◽  
pp. 256-276 ◽  
Author(s):  
M. Aly ◽  
M. S. J. Hashmi ◽  
A. G. Olabi ◽  
K. Y. Benyounis ◽  
M. Messeiry ◽  
...  
Keyword(s):  
Alkaline Treatment ◽  
Flax Fiber ◽  
Treatment Conditions

scholarly journals Optimizing the Mercerisation Effect on the Mode I Fracture Toughness of Bambusa Vulgaris Bamboo Using Surface Response Method

2020 ◽  
pp. 112-129
Author(s):  
Mohamad Zaki Hassan ◽  
Siti Amni Roslan ◽  
Zainudin A. Rasid ◽  
Mohd Zuhri Mohamed Yusoff ◽  
S. M. Sapuan ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Longitudinal Direction ◽  
Alkaline Treatment ◽  
Mode I ◽  
Mode I Fracture Toughness ◽  
Treatment Conditions ◽  
Bambusa Vulgaris ◽  
Surface Response Method ◽  
Response Method ◽  
The Comparative Study

Alkaline treatment is widely being promoted to treat natural fibres and improves the fibre bundle surface for better interlocking with the polymer matrix. The aim of this study is to optimize the merceration parameter including natrium hydroxide (NaOH) concentration, soaking and drying time for Bambusa Vulgaris bamboo using response surface methodology (RSM). Here, the treatment conditions were employed by the Box-Behnken design (BBD). The comparative study of the treated and untreated fibre on crack propagation behaviour, Mode I interlaminar fracture toughness (GIC) of the bamboo along the longitudinal direction test was carried out. Through the statistical analysis approach (ANOVA), it is suggested that bamboo treated with 1.5 wt.% concentration of NaOH is capable to reach the fracture toughness value up to 367.25 J/m2. It is also shown that all proposed variables for treatment in this study (i.e., the concentration of the NaOH is highly significant with the 2.85 hours of soaking and drying for 72.5 hours).

scholarly journals Thermal stability of water fibers: effect of the alkaline treatment - aminopropyltrimetoxysilane [Estabilidad termica de fibras de aguaje: efecto del tratamiento alcalino – aminopropiltrimetoxysilano]

2020 ◽  
Vol 4 (2) ◽  
pp. 44
Author(s):  
César Arévalo ◽  
David Manya ◽  
Victor Wong ◽  
Aldo Castillo ◽  
Hans Portilla ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Alkaline Treatment ◽  
Mass Percentage ◽  
Degradation Temperature ◽  
Treatment Conditions ◽  
Subsequent Separation ◽  
Manual Pressure ◽  
Stability Of Water ◽  
Physical Changes ◽  
Thermal Stability Of

The present research evaluated the influence of the concentration of sodium hydroxide and aminopropyltrimethoxysilane on the thermal stability of the aguaje fibers. The fibers were extracted by manual immersion in water and subsequent separation by manual pressure. The NaOH concentrations were 5%, 10% and 15% w / v; while in the case of the silane coupling agent they were 1% and 1.5% v / v. The chemically treated fibers together with the control samples were subjected to thermogravimetric analysis evaluation, in addition, the variation of the humidity percentage, the chemical variation of the main functional groups of the fibers and the surface physical changes of the fibers were determined in a complementary way. The mercerization - silanization treatments increase the thermal degradation temperature of the aguaje fibers, in the conditions tested this increase was 3.89% in the best of cases (5% NaOH + 1.0 Silane). Regarding untreated fibers, mercerization - silanization treatments decrease the percentage of lost mass or degradation, in the best of cases this decrease in mass percentage was 26.85% (15% NaOH + 1.5 Silane), compared to fibers without treatment. Finally, mercerization-silanization treatments increase the percentages of cellulose present in the aguaje fibers evaluated, while the amount of extractives and lignin decrease, under the chemical treatment conditions carried out in the present research.

scholarly journals Effect of Alkaline Treatment on Characteristics of Bio-Calcium and Hydroxyapatite Powders Derived from Salmon Bone

2020 ◽  
Vol 10 (12) ◽  
pp. 4141
Author(s):  
Anthony Temitope Idowu ◽  
Soottawat Benjakul ◽  
Sittichoke Sinthusamran ◽  
Thanasak Sae-leaw ◽  
Nobuo Suzuki ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Raw Materials ◽  
Optical Emission ◽  
Extraction Process ◽  
Alkaline Treatment ◽  
Raw Material ◽  
Inductively Coupled ◽  
Treatment Conditions ◽  
Bone Powder ◽  
Chemical And Phase Compositions

Alkaline treatment has been extensively implemented in the extraction process of hydroxyapatite (HAp) extraction from various kinds of bio-materials, such as animal bone and scales. The main purpose of such treatment is to remove proteinaceous substances from raw materials. The influence of the alkaline treatment that could alter not only the organic contents but also chemical composition—specifically the Ca/P mole ratios of bio-calcium, HAp, and the biphasic apatite powders derived from salmon bone, a by-product from the salmon industry—was investigated. Both HAp and biphasic apatite powders were obtained from the calcination of bio-calcium powders with and without alkaline treatment, respectively. An X-ray diffraction analysis confirmed the presence of hydroxyapatite and β-tricalcium phosphate (β-TCP) in the calcined bone powder without alkaline treatment while only a single phase of hydroxyapatite was observed in the alkaline-treated sample. Calcium and phosphorus contents were measured by an inductively coupled plasma optical emission spectrometer (ICP-OES). A variation of Ca/P ratios was observed among all samples, depending on the chemical and heat treatment conditions. Organic molecules, such as protein, fat, hydroxyproline, and TBARS, were significantly lowered in bio-calcium powders with the alkaline treatment. This work represents important research on chemical treatment prior to the raw material conversion process, which significantly influences chemical and phase compositions of the bio-calcium and hydroxyapatite powder derived from salmon bone waste.

Bang for Your Buck: A Single-Case Experimental Design Study of Practice Amount and Distribution in Treatment for Childhood Apraxia of Speech

2019 ◽  
Vol 62 (9) ◽  
pp. 3160-3182 ◽  
Author(s):  
Edwin Maas ◽  
Christina Gildersleeve-Neumann ◽  
Kathy Jakielski ◽  
Nicolette Kovacs ◽  
Ruth Stoeckel ◽  
...  
Keyword(s):  
Single Case ◽  
Evidence Base ◽  
Distributed Practice ◽  
Single Subject ◽  
Single Subject Design ◽  
Apraxia Of Speech ◽  
Childhood Apraxia Of Speech ◽  
Opposite Pattern ◽  
Massed Practice ◽  
Treatment Conditions

Purpose The aim of this study was to examine 2 aspects of treatment intensity in treatment for childhood apraxia of speech (CAS): practice amount and practice distribution. Method Using an alternating-treatments single-subject design with multiple baselines, we compared high versus low amount of practice, and massed versus distributed practice, in 6 children with CAS. Conditions were manipulated in the context of integral stimulation treatment. Changes in perceptual accuracy, scored by blinded analysts, were quantified with effect sizes. Results Four children showed an advantage for high amount of practice, 1 showed an opposite effect, and 1 showed no condition difference. For distribution, 4 children showed a clear advantage for massed over distributed practice post treatment; 1 showed an opposite pattern, and 1 showed no clear difference. Follow-up revealed a similar pattern. All children demonstrated treatment effects (larger gains for treated than untreated items). Conclusions High practice amount and massed practice were associated with more robust speech motor learning in most children with CAS, compared to low amount and distributed practice, respectively. Variation in effects across children warrants further research to determine factors that predict optimal treatment conditions. Finally, this study adds to the evidence base supporting the efficacy of integral stimulation treatment for CAS. Supplemental Material https://doi.org/10.23641/asha.9630599

Optimal Experimental Design With Nesting of Persons in Organizations

2013 ◽  
Vol 221 (3) ◽  
pp. 145-159 ◽  
Author(s):  
Gerard J. P. van Breukelen
Keyword(s):  
Repeated Measures ◽  
Optimal Number ◽  
Health Centers ◽  
Randomized Experiments ◽  
Optimal Sample ◽  
Treatment Conditions ◽  
Sampling Cost ◽  
Nested Designs ◽  
Simple Equations ◽  
Number Of Individuals

This paper introduces optimal design of randomized experiments where individuals are nested within organizations, such as schools, health centers, or companies. The focus is on nested designs with two levels (organization, individual) and two treatment conditions (treated, control), with treatment assignment to organizations, or to individuals within organizations. For each type of assignment, a multilevel model is first presented for the analysis of a quantitative dependent variable or outcome. Simple equations are then given for the optimal sample size per level (number of organizations, number of individuals) as a function of the sampling cost and outcome variance at each level, with realistic examples. Next, it is explained how the equations can be applied if the dependent variable is dichotomous, or if there are covariates in the model, or if the effects of two treatment factors are studied in a factorial nested design, or if the dependent variable is repeatedly measured. Designs with three levels of nesting and the optimal number of repeated measures are briefly discussed, and the paper ends with a short discussion of robust design.

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