scholarly journals Testing of experimental samples of nanofibrillar cellulose in the production of lightweight coated paper

2021 ◽  
Vol 25 (2) ◽  
pp. 90-98
Author(s):  
E.T. Tyurin ◽  
◽  
A.A. Zuikov ◽  
A.I. Bondarev ◽  
L.P. Gulyanz ◽  
...  

The influence of nanofibrillar cellulose samples on the coating compositions water retention is considered. It was shown that gels of nanofibrillar cellulose and coating compositions based on them are distinguished by a high water-retention capacity during centrifugation (50.8% and 31.0% versus 17.7% with NaCMC). A preliminary assessment of the printing and technical properties of light weight coated paper (LWC) using nanofibrillar cellulose in the coating composition has been carried out. The technical characteristics of nanofibrillar cellulose have been determined, formulations of lightweight paper coatings have been developed for high-speed modern equipment.

Author(s):  
Anthony S. R. Juo ◽  
Kathrin Franzluebbers

Allophanic soils are dark-colored young soils derived mainly from volcanic ash. These soils typically have a low bulk density (< 0.9 Mg/m3), a high water retention capacity (100% by weight at field capacity), and contain predominantly allophanes, imogolite, halloysite, and amorphous Al silicates in the clay fraction. These soils are found in small, restricted areas with volcanic activity. Worldwide, there are about 120 million ha of allophanic soils, which is about 1% of the Earth's ice-free land surface. In tropical regions, allophanic soils are among the most productive and intensively used agricultural soils. They occur in the Philippines, Indonesia, Papua New Guinea, the Caribbean and South Pacific islands, East Africa, Central America, and the Andean rim of South America. Allophanic soils are primarily Andisols and andic Inceptisols, Entisols, Mollisols, and Alfisols according to the Soil Taxonomy classification. Allophanic soils generally have a dark-colored surface soil, slippery or greasy consistency, a predominantly crumb and granular structure, and a low bulk density ranging from 0.3 to 0.8 Mg/m3. Although allophanic soils are apparently well-drained, they still have a very high water content many days after rain. When the soil is pressed between fingers, it gives a plastic, greasy, but non-sticky sensation of a silty or loamy texture. When dry, the soil loses its greasiness and becomes friable and powdery. The low bulk density of allophanic soils is closely related to the high soil porosity. For example, moderately weathered allophanic soils typically have a total porosity of 78%, with macro-, meso-, and micropores occupying 13%, 33%, and 32%, respectively. Water retained in the mesopores is readily available for plant uptake. Water retained in the micropores is held strongly by soil particles and is not readily available for plant use. The macropores provide soil aeration and facilitate water infiltration. The high water retention capacity is also associated with the high soil porosity. In allophanic soils formed under a humid climate, especially those containing large amounts of allophane, the moisture content at field capacity can be as high as 300%, calculated on a weight basis. Such extremely high values of water content seem misleading.


Author(s):  
Thomas Cornelius Buch-Hanser ◽  
Guangli Du ◽  
David John Duffus

<p>Given the rapid increase in urban populations, combined with the effects of climate change, cities are struggling to provide green spaces to address liveability as well as adaptability to new challenges. Water retention and bio-diversity are the main advantages of green roofs. There are, however, limitations to green roofs that impede their acceptance and proliferation. There is for example uncertainty on how much water they retain during major storm events. In terms of building technology, green roofs today aren’t robust, and the risk for leakage through the roof membrane is disproportionally high when compared to the cost. A newly developed innovative green roof system with high water retention capacity and high durability will be presented. The patented prefabricated technology incorporate insulation and membrane into a single concrete element, ensuring improved robustness, quickened building times and a long term durable product. Initial indications for pricing indicate that the system is price-neutral when compared with green roofs as they are built today. The optimized structural performance obtain same loadbearing capacity, as existing systems, in spite of the relatively increased space created for water reservoir, without compromising the insulation capacity, hence the new green roof system further contribute to increased sustainability.</p>


Author(s):  
Pradeesh V ◽  
Karthikeyan S ◽  
Prabakaran D

Curing plays a chief function in the improving the strength of concrete. The function of a self-curing agent is to save the water and to reduce the water evaporation from the concrete, and hence they increase the water retention capacity of concrete compared to the conventionally cured concrete. Prosopisjuliflora root powder is used as admixtures for self-curing concrete in this study. Prosopisjuliflora (SeemaiKaruvelam in Tamil) grows tremendously and spreads due to its mechanism to overcome adverse conditions of like drought and salt. With deep penetrating roots, it can draw water from deeper layers. Their root has high water holding capacity, so powder made from it can be used as admixture for self-curing concrete. This project involves the experimental investigation of self-curing of concrete by using Prosopisjuliflora root powder. Tests on fresh concrete and hardened concrete were conducted. From the results, we have concluded that adding prosopisjuliflora root powder as a self-curing agent in the concrete mix at various percentages, the addition of 0.75% of prosopisjuliflora root powder by the weight of cement attains the 28 days compressive strength of a conventional M25 grade concrete in 7 days.


2020 ◽  
Vol 16 (3) ◽  
pp. 12-17
Author(s):  
Joabe Freitas Crispim ◽  
Jailma Suerda Silva de Lima ◽  
Jessika Kaliane Barbosa da Silva ◽  
Antônio Gideilson Correia da Silva ◽  
Gabriel Kariel Ferreira Ferdandes ◽  
...  

The biochar obtained from pyrolysis of vegetable biomass gives the plant a good nutritional supply and has a high water retention capacity, however there are still few studies evaluating its use in the production of leafy vegetable seedlings. With that, the objective of this work was to determine proportions of biochar in sand that allow better development of rocket seedlings. The experiment was conducted in a greenhouse at the Federal Rural University of the Semi-Arid (UFERSA). The experimental design used was completely randomized with six treatments (0; 10; 20; 30; 40; 50% of biochar) and ten replications. The evaluated characteristics were: Twinning; Number of leaves per plant; Root length; Plant height; Neck diameter; Fresh and dry mass of plants and water content in the plant. The data were submitted to analysis of variance. The procedure for adjusting the response curves was performed using the R software. The 50% biochar proportion is recommended in the production of arugula seedlings as it provides better development in the plants, promoting significant improvements in all the characteristics analyzed, except germination and number of leaves per plant.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1510
Author(s):  
María Ángeles Rivas ◽  
Rocío Casquete ◽  
María de Guía Córdoba ◽  
Santiago Ruíz-Moyano ◽  
María José Benito ◽  
...  

The objective of this study was to evaluate, from a technological and nutritional point of view, the chemical composition and functional properties of the industrial winemaking by-products, namely skins, stems and lees. The chemical and physical characteristics, as well as the functional properties (fat and water retention and swelling capacity, antioxidant capacity, and their prebiotic effect), of the dietary fibre of these by-products were studied. The results showed that the skins, stems, and lees are rich in fibre, with the stem fibre containing the highest amounts of non-extractable polyphenols attached to polysaccharides with high antioxidant activity and prebiotic effect. Lee fibre had the highest water retention capacity and oil retention capacity. The results reveal that winemaking by-products could be used as a source of dietary fibre with functional characteristics for food applications.


2005 ◽  
Vol 21 (6) ◽  
pp. 651-660 ◽  
Author(s):  
Klaus Mehltreter ◽  
Alejandro Flores-Palacios ◽  
José G. García-Franco

The diversity, abundance and frequency of vascular epiphytes on the lower trunk were compared between two host groups of a Mexican cloud forest: angiosperm trees (n = 72) and tree ferns (n = 28). The bark of the five most frequent host trees and the root mantle of the two tree ferns were analysed for their thickness, water content, water retention capacity and pH. A total of 55 epiphyte species and 910 individuals were found on the 27 host species. On hosts with a dbh range of 5–10 cm, epiphytes were significantly more diverse (4.3±0.9 species per host) and more abundant (12.5±2.2 individuals per host) on tree ferns than on angiosperm trees (1.9±0.2 species per host and 3.9±0.6 individuals per host). However, these differences were not significant for the dbh class of 10–20 cm, because epiphyte numbers increased on angiosperm trees with larger host size, but not in tree ferns. Most epiphyte species had no preference for any host group, but four species were significantly more frequent on tree ferns and two species on angiosperm trees. The higher epiphyte diversity and abundance on tree fern trunks of the smallest dbh class is attributed to their presumably greater age and to two stem characteristics, which differed significantly between host groups, the thicker root mantle and higher water retention capacity of tree ferns. These bark characteristics may favour germination and establishment of epiphytes.


Author(s):  
Sandoval-Gallegos Eli Mireya ◽  
Arias-Rico José ◽  
Cruz-Cansino Nelly del Socorro ◽  
Ramírez-Ojeda Deyanira ◽  
Zafra-Rojas Quinatzin Yadira ◽  
...  

The aim of the present research was to determine the effect of boiling on nutritional composition, total phenolic compounds, antioxidant capacity, physicochemical and morphological characteristics of two edible plants Malva parviflora (mallow leaf) and Myrtillocactus geometrizans (garambullo flower). The plants had an important nutritional composition as carbohydrates (48-70 %), dietary fiber (36-42 %) and protein (13 %), as well as total phenolic compounds (468-750 mg GAE/100 g db) with a high antioxidant capacity. However, boiling originated the decrease of soluble compounds, carbohydrates, total phenolic compounds, antioxidant capacity and physicochemical properties. Plants changed to dark colors and physicochemical properties were affected, except to water retention capacity, oil retention capacity and viscosity, which had the same values in mallow leaves (raw and boiled), but increased water retention capacity in garambullo flowers, it may be by changes in the morphology observed. Therefore, is to suggest the raw consumption or with minimal cooking of these plants to avoid changes caused by thermal treatment.


Author(s):  
Kun Sha ◽  
Ping Qian ◽  
Li-Jun Wang ◽  
Zhan-hui Lu ◽  
Li-Te Li

In this study, quality of Man-tou, the Chinese traditional steamed bread during storage was studied. Values for water retention capacity, total water solubles, soluble starch, and soluble amylose and amylopectin of Man-tou decreased with storage time. Results showed that hardness, chewiness and gumminess of Man-tou increased, while, springiness cohesiveness and resilience decreased along with prolonged storage time (p<0.05). Sensory evaluation results showed that all sensory rating of Man-tou, including softness, stickiness, cohesiveness, elasticity, taste and total score, dropped drastically within 24 h of storage time (p<0.05). Differential Scanning Calorimeter (DSC) was used to determine crystalline structure of amylopectin in Man-tou, and the value for enthalpy of crystallization was found increased with storage time. Amylopectin crystallization was significantly associated to Man-tou firming (p<0.01).


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