scholarly journals Microstructural changes and the effect on myofibril proteins in yamu (Brycon amazonicus) fish meat during cold storage

2016 ◽  
Vol 34 (3) ◽  
pp. 403-414 ◽  
Author(s):  
Daniel Castañeda ◽  
José Manuel Lozano ◽  
Héctor Suárez
Keyword(s):  
Cold Storage ◽  
Structural Changes ◽  
Storage Temperature ◽  
Protein Profile ◽  
Chemical Properties ◽  
Water Retention Capacity ◽  
Retention Capacity ◽  
Fish Meat ◽  
Negative Effect ◽  
Physical And Chemical

This study aimed to evaluate the effect of cold storage on yamu fish meat (Brycon amazonicus). The methodology consisted of analyzing two temperatures (0±1.6°C and -8±1°C), two storage periods (13 and 61 hours) and two different sources (farm and river), and determine changes in the protein profile, micro structural, physical and chemical properties (water retention capacity-WRC, pH, texture of yamu meat fillets). The micro-structural changes were observed with optical and scanning electron microscopy. The results of the image analysis of the meat microstructure showed a negative effect from cold storage on the muscle, affecting the connective tissue. Otherwise, the analysis of protein profile demonstrated protein degradation during the cold storage of the yamu meat, such as for heavy chain myosin, actin and a-actinin. In addition, the origin of the fish and the storage temperature had a significant effect on the texture changes (P<0.05); meanwhile, the storage time had a significant effect on the three technological characteris tics of the meat (WRC, pH and texture) (P<0.05). The storage temperature did not significantly affect the WRC (P>0.05).

scholarly journals Decomposition of Plantain Peel Powder and Assessment of its Effects on Soil Physical and Chemical Characteristics

2021 ◽  
pp. 11-24
Author(s):  
Alla Kouadio Théodore ◽  
Gbeze Kpata Hermann Roland ◽  
Bomisso Edson Lezin
Keyword(s):  
Organic Fertilizer ◽  
Chemical Properties ◽  
Thick Layer ◽  
Water Retention Capacity ◽  
Chemical Characteristics ◽  
Retention Capacity ◽  
Sea Sand ◽  
Phosphorus And Potassium ◽  
Set Up ◽  
Physical And Chemical

This study aims at assessing the effects of plantain (Musa paradisiaca) peel powder on soil physical and chemical properties in the context of sustainable yield management. The experiment took place in the laboratory of plant physiology of the University Félix Houphouët Boigny from July to November 2020. Three designs were set up. Design 1 consisted of 20 g of plantain peel powder added to a 2-cm thick layer of sea sand. Design 2 consisted of 5 g of plantain peel powder added to 250 g of sea sand. Design 3 consisted of a homogeneous mixture of 100 g of peel powder and 200 g of rhizospheric tomato or plantain soil. The designs were regularly watered with distilled water. In the first two designs, the plantain peel powder was added according to two methods. These included surface incorporation and deep incorporation. The experiment allowed us to characterize peel powder decomposition and assess its effects on soil physicochemical parameters. The physico-chemical characteristics of the soils were subjected to a one-way analysis of variance (ANOVA 1). STATICA 7.1 software was used to perform all the analyses. Analysis of the results showed that the incorporation method does not influence peel powder decomposition. This decomposition is followed by the release of colored elements. Water retention capacity as well as particle size were improved. The results showed that plantain peel powder is an important source of minerals mainly phosphorus and potassium. It emerges from this study that plantain peel could be a good organic fertilizer for profitable and environmentally friendly agriculture.

scholarly journals Thermochemical and Structural Analysis of Tautomers of Sulfur and Selenium Modified RNA Nucleobases

2019 ◽  
Vol 2 (2) ◽  
pp. 47-48
Author(s):  
Megan Joy ◽  
Alex Brown ◽  
Arturo Mora Gomez ◽  
Maria Rossano-Tapia ◽  
Shyam Parshotam
Keyword(s):  
Ir Spectra ◽  
Structural Changes ◽  
Chemical Properties ◽  
Hydrogen Atoms ◽  
Relative Population ◽  
Geometry Analysis ◽  
Physical And Chemical ◽  
Modified Nucleobases ◽  
Relative Gibbs Free Energy ◽  
And Chemical Properties

Nucleobases (adenine, cytosine, guanine, and uracil), the four molecules that forms RNA, have been found to be useful in probing in the human body when modified because they can emit light. Non-modified nucleobases do not exhibit emissive properties and cannot be used as probes. Some of the modifications include the substitution of nitrogen atoms with sulfur and selenium, and the resulting modified nucleobases give place to the so-called tz- and ts- RNA alphabets, respectively. Therefore, the aim of this project was to provide insights about the viability, from a computational perspective, of using the modified nucleobases as probes, evaluating the differences in thermochemical, structural and emissive properties of the modified nucleobases with respect to the non-modified ones. Nucleobases can coexist with other modified nucleobases or tautomers, molecules that differ due to the change in position of hydrogen atoms in a molecule’s structure and as a result have different physical and chemical properties. The thermochemical properties evaluation mainly consisted in the computation of the relative Gibbs Free Energy (G), which is related to the fraction F, an index of the relative population among tautomers. This was done using Gaussian 09 software by performing geometry analysis and frequency computations on each one of the tautomers. By comparing the equilibrium fractions, it was determined that in both cases, tz- and ts- guanine and cytosine exist principally in the form of one of their tautomers (Cytosine 2 and Guanine 2) as in the case of the non-modified cases. After confirming which tz- and ts- tautomers were the ones with the largest probable population, infrared (IR) and ultraviolet-visible (UV-vis) spectra were obtained. The IR spectra of selenium and sulfur tautomers of guanine and cytosine indicated that the tautomers had peaks at similar frequencies with respect to each other, however, the intensities varied, implying slight structural changes between the tautomers. On the other hand, the UV-vis spectra showed a change in peak positions between the tautomers with sulfur and selenium, suggesting that the change between sulfur and selenium has an effect on the spectra by shifting the peaks from the original molecules’ λmax values. Their relative population fractions show that only the canonical forms of the modified nucleobases exist in a larger extent than the rest of their tautomer forms. In addition, the features in their UV-vis and IR spectra allow these tautomers to be differentiated from each other.

Experimental Investigation on Grinding Temperature of Titanium Alloy

2014 ◽  
Vol 1027 ◽  
pp. 127-130 ◽  
Author(s):  
Bing Jun Hao ◽  
Zhi Gang Dong ◽  
Ren Ke Kang ◽  
Huan Wang ◽  
Ke Cao
Keyword(s):  
Titanium Alloy ◽  
Structural Changes ◽  
Thermal Damage ◽  
Elevated Temperatures ◽  
Chemical Properties ◽  
Grinding Temperature ◽  
Physical And Chemical Properties ◽  
Machine Material ◽  
Physical And Chemical ◽  
And Chemical Properties

Titanium alloy has been widely used in aeronautics and astronautics industry owing to its unique combinations of properties. The unique physical and chemical properties of titanium alloy make it a typical difficult-to-machine material. The elevated temperatures at the machining zones may cause thermal damage, residual stress and micro-structural changes in the surface layer of titanium alloy during grinding. In this study, grinding experiments were performed on the titanium alloy, and the grinding temperature was experimentally tested with the grindable thermocouples. The effects of the grinding parameters on the grinding temperature were analyzed. The grinding temperature rises with the increase of grinding speed and grinding depth.

Tuning Packing, Structural Flexibility, and Porosity in 2D Metal–Organic Frameworks by Metal Node Choice

2019 ◽  
Vol 72 (10) ◽  
pp. 797 ◽  
Author(s):  
Witold M. Bloch ◽  
Christian J. Doonan ◽  
Christopher J. Sumby
Keyword(s):  
Structural Changes ◽  
Metal Organic Frameworks ◽  
Chemical Properties ◽  
Complete Removal ◽  
Structural Flexibility ◽  
X Ray Diffraction ◽  
Metal Centre ◽  
Metal Organic ◽  
Physical And Chemical ◽  
And Chemical Properties

Understanding the key features that determine structural flexibility in metal–organic frameworks (MOFs) is key to exploiting their dynamic physical and chemical properties. We have previously reported a 2D MOF material, CuL1, comprising five-coordinate metal nodes that displays exceptional CO2/N2 selectively (L1=bis(4-(4-carboxyphenyl)-1H-pyrazolyl)methane). Here we examine the effect of utilising six-coordinate metal centres (CoII and NiII) in the synthesis of isostructural MOFs from L1, namely CoL1 and NiL1. The octahedral geometry of the metal centre within the MOF analogues precludes an ideal eclipse of the 2D layers, resulting in an offset stacking, and in certain cases, the formation of 2-fold interpenetrated analogues β-CoL1 and β-NiL1. We used a combination of thermogravimetric analysis (TGA), and powder and single crystal X-ray diffraction (PXRD and SCXRD) to show that desolvation is accompanied by a structural change for NiL1, and complete removal of the coordinated H2O ligands results in a reduction in long-range order. The offset nature of the 2D layers in combination with the structural changes impedes the adsorption of meaningful quantities of gases (N2, CO2), highlighting the importance of a five-coordinate metal centre in achieving optimal pore accessibility for this family of flexible materials.

scholarly journals Effect of Biochar Amendment in Woodchip Denitrifying Bioreactors for Nitrate and Phosphate Removal in Tile Drainage Flow

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2883
Author(s):  
Rasa Vismontienė ◽  
Arvydas Povilaitis
Keyword(s):  
Chemical Properties ◽  
Pilot Scale ◽  
Drainage Water ◽  
Tile Drainage ◽  
Phosphate Removal ◽  
Retention Capacity ◽  
N Removal ◽  
Physical And Chemical ◽  
P Removal ◽  
Biochar Amendment

Biochar has received increased attention in environmental applications in recent years. Therefore, three pilot-scale denitrifying bioreactors, one filled with woodchips only and the other two enriched with 10% and 20% by volume of biochar from deciduous wood, were tested under field conditions for the removal of nitrate (NO3-N) and phosphate (PO4-P) from tile drainage water in Lithuania over a 3-year period. The experiment showed the possibility to improve NO3-N removal by incorporating 20% biochar into woodchips. Compared to the woodchips only and woodchips amended with 10% biochar, the NO3-N removal effect was particularly higher at temperatures below 10.0 °C. The results also revealed that woodchips alone can be a suitable medium for PO4-P removal, while the amendment of biochar to woodchips (regardless of 10% or 20%) can lead to large releases of PO4-P and other elements. Due to the potential adverse effects, the use of biochar in woodchip bioreactors has proven to be very limited and complicated. The experiment highlighted the need to determine the retention capacity of biochar for relevant substances depending on the feedstock and its physical and chemical properties before using it in denitrifying bioreactors.

scholarly journals Influence of fertilizer and hydrogel on physical-chemical attributes of substrate for seedling production

2019 ◽  
Vol 35 (5) ◽  
Author(s):  
Glauce Taís de Oliveira Sousa Azevedo ◽  
Anderson Marcos de Souza ◽  
Gileno Brito de Azevedo ◽  
Paulo Eduardo Teodoro ◽  
José Raimundo Luduvico de Sousa
Keyword(s):  
Water Retention ◽  
Water Retention Capacity ◽  
Forest Nursery ◽  
Retention Capacity ◽  
Physical Chemical ◽  
Physical Attributes ◽  
Chemical Attributes ◽  
Physical And Chemical ◽  
Different Levels ◽  
Different Doses

The incorporation of the hydrogel into the substrate used in the forest nursery promotes improvements in its physical-chemical attributes. However, several factors influence the hydrogel efficiency, such as the increase of salts, promoted by fertilizer of the substrate. Therefore, this study aimed to evaluate the effects of the incorporation of fertilizer levels and hydrogel doses on the physical-chemical attributes of a substrate to produce forest seedlings. Different levels of basic fertilizer commonly used in the nursery (100%, 50% and 0%) and different doses of the hydrogel (0, 1, 2 and 3 g L-1) were incorporated into the substrate Tropstrato Florestal®, consisting of 12 treatments in a 3 x 4 factorial scheme. A sample of the substrate in each treatment was sent for analysis of its physical and chemical attributes. To evaluate the effect of the treatments on the physical-chemical attributes of the substrate, was used the multivariate principal components analyses. The levels of fertilizer and hydrogel doses were correlated with the attributes of the substrates obtained in each treatment. The incorporation of different fertilizer levels and hydrogel doses to the substrate modified their chemical and physical attributes. Fertilizers have influenced mainly the chemical attributes of the substrate, whereas hydrogels have influenced the physical attributes, mainly those related to water retention capacity and availability.

scholarly journals Production of kale seedlings on substrates containing proportions of organic compost

2021 ◽  
Vol 10 (8) ◽  
pp. e58010817707
Author(s):  
José Luís Trevizan Chiomento ◽  
Isabel Cristina Lourenço da Silva ◽  
Lourival Dantas Fagundes ◽  
Rafael Tronco Homrich ◽  
Nicolas dos Santos Trentin ◽  
...  
Keyword(s):  
Root System ◽  
Aerial Part ◽  
Water Retention ◽  
Chemical Characterization ◽  
Water Retention Capacity ◽  
Retention Capacity ◽  
The One ◽  
Physical And Chemical ◽  
Organic Compost

One of the difficulties in the kale seedlings production in containers is to ensure the production of aboveground biomass with a limited portion of roots, restricted to a small volume of substrate. Thus, we investigated whether substrates with organic compost added to it associated with kale cultivars interfere in the quality of seedlings produced in a greenhouse. Here, we studied two kale cultivars and five substrates. The experiment was designed in randomized blocks, with treatments arranged in a bifactorial scheme (2 x 5), with three replications. We carried out the physical and chemical characterization of the substrates and evaluated attributes of the aerial part and root system of the kale seedlings. The results showed that the substrate with the highest water retention was the one without the addition of organic compost. The greater the proportion of organic compound added to the substrate, the higher the nitrogen, phosphorus and organic carbon values. Seedlings produced in the substrate with greater water retention capacity had better performance in relation to the morphology of the aerial part and the morphology of the root system. We conclude that seedlings of kale cultivars associated with substrates with higher water retention have better quality. Seedlings of the ‘Gaudina’ cultivar stand out for their better phytometric morphology, while seedlings of the ‘Manteiga’ cultivar have higher quality of root biomass.

scholarly journals SINTESA DAN KARAKTERISASI HIDROGEL SUPER ABSORBEN POLIMER (SAP) BERBASIS SELULOSA MENGGUNAKAN CROSSLINKING AGENT WATER-SOLUBLE CARBODIIMIDE (WSC)

2015 ◽  
Vol 5 (01) ◽  
Author(s):  
Lik Anah ◽  
Nuri Astrini
Keyword(s):  
Water Uptake ◽  
Structural Changes ◽  
Raw Materials ◽  
Crosslinking Agent ◽  
Monomer Concentration ◽  
Water Soluble ◽  
Hydroxyethyl Cellulose ◽  
Water Retention Capacity ◽  
Retention Capacity ◽  
Absorbent Polymer

Carboxymethylcellulose (CMCNa), hydroxyethyl cellulose (HEC) were used as raw materials for synthesizing a superabsorbent polymer (SAP) hydrogel by solution polymerization techniques using of 2.5% water-soluble carbodiimide (WSC) as crosslinking agent and 1% citric acid as catalysator. The  ratio of CMCNa to HEC at 1 : 1; 3 : 1; 5 : 1 and 10 : 1 were used as variable of process. The effect of monomer concentration on water absorbency and water uptake was studied. The swelling test showed that the highest water retention capacity (6.58 g/g) was reached at ratio CMCNa to HEC = 5 : 1 in 100 minutes and the deswelling test ( 61.47%) was reached at ratio CMCNa to HEC = 5 :1 in 120 minutes. PPA absorb hydrogel was used as standard with equilibrium swelling 123 g/g. The SAP hydrogel were characterized by infra red spectroscopy, and the result showed that there were some of structural changes in height of few bands of hydrophylic groups such as =C-H at 2930 cm-1, C-H antisym and sym at 2875 cm-1, H-bonded –OH at 2375 cm-1, -COO- antisym at 1600 cm-1 whereas C-O at 1025 cm-1.Keywords: hydrogel, SAP, swelling, crosslinking, WSCABSTRAKSuper Absorbent Polymer (SAP) hydrogel yang disintesa melalui proses polimerisasi Carboxymethylcellulose (CMCNa), Hydroxyethyl Cellulose (HEC) menggunakan Water- soluble Carbodiimide (WSC) sebagai crosslinking agent telah dilakukan melalui teknik polimerisasi larutan (solution polimerization techniques). Pada percobaan awal telah ditetapkan konsentrasi monomer sebagai variabel proses yaitu CMCNa / HEC rasio = 1:1, 3:1, 5:1, 10:1 dan masing- masing rasio direaksikan dengan 2,5 % WSC dan 1 % asam sitrat sebagai katalisator. Pengaruh konsentrasi monomer diiuji dari kemampuan hasil gel yang terbentuk dalam menyerap dan mengikat air (water uptake) yang divisualisasikan sebagai swelling dan deswelling ratio. Hasil uji swelling menunjukkan bahwa derajat swelling tertinggi dicapai pada rasio CMCNa / HEC = 5:1 dalam waktu 100 menit dengan derajat swelling = 6,58 g/g. Hidrogel PPA absorb komersial digunakan sebagai standar pembanding dengan derajat swelling 123 g/g. Hasil uji deswelling menunjukkan bahwa persentase retensi air dalam gel adalah 61,47 % untuk rasio CMCNa / HEC = 5:1 pada 120 menit. Hasil karakterisasi gugus fungsi melalui analisis FTIR menunjukkan bahwa ada perbedaan nyata antara selulosa awal dengan selulosa yang direaksikan dengan WSC. Pita serapan tajam untuk gugus fungsi =C-H berada pada bilangan gelombang 2930 cm-1 dan C-H antisym dan sym terjadi pada 2875 cm-1, H-bonded-OH pada 2375 cm-1, gugus fungsi –COO- antisym berada pada bilangan gelombang 1600 cm-1, dan C-O terjadi pada 1025 cm-1.Kata kunci: hidrogel, SAP, swelling, crosslinking, WSC

scholarly journals PHYSICOCHEMICAL AND FUNCTIONAL PROPERTIES OF DIETARY FIBER FROM BAMBOO SHOOTS (PHYLLOSTACHYS PRAECOX)

2017 ◽  
pp. 509 ◽  
Author(s):  
Cai-Hong Wang ◽  
Yi-Long Ma ◽  
Dan-Ye Zhu ◽  
Hao Wang ◽  
Ya-Fei Ren ◽  
...  
Keyword(s):  
Particle Size ◽  
Dietary Fiber ◽  
Functional Properties ◽  
Chemical Properties ◽  
Water Retention Capacity ◽  
Retention Capacity ◽  
Bamboo Shoots ◽  
Health Products ◽  
Potential Applications ◽  
Physicochemical And Functional Properties

Dietary fiber are non-digestible constituents of plant cell walls, and comprise a necessary component of diet and its positive connection with human health. Till now, there is no report about the extraction and physicochemical and functional properties of dietary fiber from bamboo shoots. To find the potential applications of dietary fiber from bamboo shoots in food and health products, the effects of chemical, enzymatic methods and particle size distribution on the chemical and structural composition, physicochemical, and functional properties of dietary fibers (DFs) from bamboo shoots were studied. The results showed that BSEDF and BSCDF had higher total DF and higher soluble DF, respectively. The crystalline regions calculated to be higher in latter and both had irregular surfaces and diverse monosaccharide composition. Both fibers showed good functional properties [water retention capacity (WRC) (11.24-15.13g/g), water swelling capacity (WSC) (18.84-28.75 mL/g), oil holding capacity (OAC) (6.71-10.15 g/g), glucose adsorption capacity (GAC) (0.08-6.89 mmol/g) and glucose retardation index (GRI) (3.57-40.92%)]. WRC of BSCDF and BSEDF decreased with the increase in the mesh size (40-200) while, WSC and OAC increased with mesh sizes (40 to 120), followed by decrease above mesh120. Both particle size and extraction methods significantly affected GRI. In conclusion, physico-chemical properties of fibers can be manipulated through treatments (chemical and enzymatic) to improve their overall functionality. Therefore, both BSCDF and BSEDF can find potential applications in food and health products as a functional ingredient in different aspects.

scholarly journals Monitoring of Selected Physical and Chemical Parameters of Test Oil in the Wet Disc Brake System

2020 ◽  
Vol 23 (1) ◽  
pp. 46-52 ◽  
Author(s):  
Juraj Jablonický ◽  
Mirko Simikić ◽  
Juraj Tulík ◽  
Milan Tomić ◽  
Ľubomír Hujo ◽  
...  
Keyword(s):  
Physical Properties ◽  
Negative Impact ◽  
Chemical Properties ◽  
Fluorescence Analysis ◽  
Acid Number ◽  
Brake System ◽  
Disc Brake ◽  
Operational Tests ◽  
Negative Effect ◽  
Physical And Chemical

AbstractPaper presented is focused on the operating measurements of a tractor wet disc brake system. Operating measurements were evaluated after tractor’s operation at 500 Mth on the 3rd, 4th and 5th gear. Reference fluid and ecological fluid were tested during operation. In addition, work results include the evaluation of the fluid samples taken during the operational tests to monitor the tractor braking performance with wet disc brakes. Fluid samples were also tested in order to determine the changes in their physico-chemical properties. Chemical analysis was performed for both oil samples by means of X-ray fluorescence analysis according to the DIN 51829 and DIN 51399-2. Observed physical properties of the tested oils – density, viscosity, acid number, water content – were within the appropriate ranges after the end of test. Further analysis was focused on an amount of abrasive metals, contaminants, additives, and other important elements. On the basis of analyses conducted, it can be concluded that majority of elements preserved their original level showed at the 0 reference hour sample. In terms of the abrasion metals, an increase in their presence was not found. Furthermore, analysis of the physical properties of tested fluids did not prove their negative impact on the tractor wet disc brake system. Results of the operating measurements suggest that neither the applied conference fluid nor the ecological fluid showed negative effect on the minimum braking value. The minimum braking deceleration was implemented in accordance with the Law no. 106/2018.

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