moisture increase
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Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 3010
Author(s):  
Meritxell Martí ◽  
Jaime Gisbert-Paya ◽  
Mª Ángeles Bonet-Aracil ◽  
Petar Jovančić ◽  
Manuel J. Lis ◽  
...  

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.


CivilEng ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 599-611
Author(s):  
Nuha Mashaan ◽  
Mohamed Karim ◽  
Farag Khodary ◽  
Nikhil Saboo ◽  
Abdalrhman Milad

This paper attempts to display, analyze and discuss the literature affiliated to the previous research data on road surfacing in pavement engineering reinforcement. In this paper, a review of the background and present status of road surfacing is also provided for supportive explanation of the significance of fiber-reinforced asphalt pavement HMA and its role in providing effective and durable surfacing for heavy-trafficked roads. The paper attempts to clarify some of the terms and notions related to the discussions to give the readers the needed background, to be able to actively understand the experiments and discussions. Results from many studies confirm that fiber specifically enhances the optimum bitumen content in the design of the mixture and halts the bitumen leakage due to its asphalt absorbing susceptibility. Fiber modifies the visco-elastic response, susceptibility against moisture, increase resistance to rutting, as well as lowers the pavement fatigue cracking.


Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4104
Author(s):  
Iuliana Gageanu ◽  
Dan Cujbescu ◽  
Catalin Persu ◽  
Paula Tudor ◽  
Petru Cardei ◽  
...  

This paper presents theoretical and experimental research studying the influence of process parameters on the quality of biomass pellets. A validated mathematical model was developed, expressing the density of biomass pellets as determined by moisture content, compression pressure, process heat, the initial density of the material, pelleting speed and initial volume of the material. The experiments for determining the influence of these parameters on the compression of biomass into pellets and optimizing the process were conducted on a heated single pellet compression device, using fir sawdust as raw material. To describe and study the process, four input and control parameters were varied—raw material moisture, pelleting speed, maximum force applied and pelleting die temperature. From the experiments, it was noticed that overall, moisture and pressure have the most important effect on the compression process and pelleting speed, and heat applied also affected the process. Pellet density decreased when pelleting speed and material moisture increase and the density increased with a higher compression pressure and higher heat during the process.


2021 ◽  
Vol 17 (1) ◽  
pp. 1-8
Author(s):  
Jollanda Effendy ◽  
Don R LaBonte ◽  
Darda Efendi ◽  
Nurul Khumaida ◽  
Gustaaf A Wattimena

In sweetpotatoes (Ipomoea batatas L. Lamb), the loss of skin from the surface of the storage roots is known as skinning injury. It is responsible for significant postharvest loss resulting from moisture increase and weight reduction, wrinkling, and susceptibility to pathogen attack. Reduced root weight by water loss is associated with a higher rate of rot predominantly occurred in the developing and underdeveloped countries which can count of 8-20% of postharvest loss. Plants have different adaptation to protect themselves against skinning injury. Lignification, suberization, and increased sugar at the wound site have been shown to be correlated with wound healing. Changing in gene expressions have been associated with skinning injury. Genes associated in the biosynthesis of lignin and suberin, protein fate, cell-wall modification, transcription and protein synthesis, and stress responses and defense have been associated with skinning injury responses in plants. Understanding the skinning injury responses and how to regulate them can be used to produce a more desirable plant resistant to skinning injury. This paper especially reviews and discusses skinning injury responses in sweetpotato, a root crop which product may severely be affected by skinning injury. Keywords: gene expression, Ipomoea batatas, lignification, postharvest loss, wounding   ABSTRAK Pada ubi jalar (Ipomoea batatas L. Lamb), cedera kulit adalah hilangnya kulit dari permukaan umbi. Cedera kulit ini bertanggung jawab atas kerugian pascapanen yang signifikan akibat peningkatan laju kelembaban dan penurunan berat umbi, pengerutan, dan kerentanan terhadap serangan patogen. Berat umbi yang berkurang karena kehilangan air dikaitkan dengan tingkat pembusukan yang lebih tinggi, terutama terjadi di negara-negara berkembang dan yang kurang berkembang dengan kehilangan hasil panen umbi 8-20%. Tanaman memiliki adaptasi yang berbeda untuk melindungi diri dari cedera kulit. Lignifikasi, suberisasi, dan peningkatan gula di lokasi pelukaan telah terbukti berkorelasi dengan penyembuhan luka. Perubahan ekspresi gen telah dikaitkan dengan cedera kulit. Gen-gen yang terlibat dalam jalur biosintesis lignin dan suberin, protein tujuan akhir, modifikasi dinding sel, transkripsi dan sintesis protein, serta respons stres dan pertahanan telah dikaitkan dengan respons cedera kulit pada tanaman. Memahami respons cedera kulit dan bagimana cara mengaturnya dapat digunakan untuk menghasilkan tanaman yang diinginkan yang tahan terhadap cedera kulit umbi. Paper ini secara khusus mengulas dan membahas respon cedera kulit pada ubi jalar, suatu tanaman umbian yang hasilnya sangat terpengaruh oleh cedera kulit. Kata kunci: ekspresi gen, Ipomoea batatas, lignifikasi, kehilangan pascapanen, pelukaan


Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 407
Author(s):  
Huili Feng ◽  
Jiahuan Guo ◽  
Saadatullah Malghani ◽  
Menghua Han ◽  
Penghe Cao ◽  
...  

Improved mechanistic understanding of soil methane (CH4) exchange responses to shifts in soil moisture and temperature in forest ecosystems is pivotal to reducing uncertainty in estimates of the soil-atmospheric CH4 budget under climate change. We investigated the mechanism behind the effects of soil moisture and temperature shifts on soil CH4 fluxes under laboratory conditions. Soils from the Huai River Basin in China, an area that experiences frequent hydrological shifts, were sampled from two consecutive depths (0–20 and 20–50 cm) and incubated for 2 weeks under different combinations of soil moisture and temperature. Soils from both depths showed an increase in soil moisture and temperature-dependent cumulative CH4 fluxes. CH4 production rates incubated in different moisture and temperature in surface soil ranged from 1.27 to 2.18 ng g−1 d−1, and that of subsurface soil ranged from 1.18 to 2.34 ng g−1 d−1. The Q10 range for soil CH4 efflux rates was 1.04–1.37. For surface soils, the relative abundance and diversity of methanotrophs decreased with moisture increase when incubated at 5 °C, while it increased with moisture increase when incubated at 15 and 30 °C. For subsurface soils, the relative abundance and diversity of methanotrophs in all samples decreased with moisture increase. However, there was no significant difference in the diversity of methanogens between the two soil depths, while the relative abundance of methanogens in both depths soils increased with temperature increase when incubated at 150% water-filled pore space (WFPS). Microbial community composition exhibited large variations in post incubation samples except for one treatment based on the surface soils incubated at 15 °C, which showed a decrease in the total and unique species number of methanotrophs with moisture increase. In contrast, the unique species number of methanogens in surface soils increased with moisture increase. The analysis of distance-based redundancy analysis (db-RDA) showed that soil pH, dissolved organic carbon (DOC), dissolved organic nitrogen (DON), microbial biomass carbon (MBC), NO3−-N, and NH4+-N mainly performed a significant effect on methanotrophs community composition when incubated at 60% WFPS, while they performed a significant effect on methanogens community composition when incubated at 150% WFPS. Overall, our findings emphasized the vital function of soil hydrology in triggering CH4 efflux from subtropical plantation forest soils under future climate change.


Author(s):  
Hsu-Feng Teng ◽  
Ying-Hwa Kuo ◽  
James M. Done

AbstractThis study explores the importance of mid-level moisture for tropical cyclone (TC) formation in monsoon and easterly environments over the western North Pacific in regional simulations (15-km resolution). The Weather Research and Forecasting (WRF) model is used to simulate 22 TCs that form in monsoon environments (MTCs) and 13 TCs that form in easterly environments (ETCs) over the period 2006–2010. To characterize the moisture contribution, simulations with mid-level moisture improved through assimilation of global positioning system (GPS) radio occultation (RO) data (labeled as EPH) are compared to those without (labeled as GTS). In general, the probability of TC formation being detected in the simulations is higher for MTCs than ETCs, regardless of GPS RO assimilation, especially for the monsoon trough environment. Fifty-four percent of ETC formations are sensitive to the mid-level moisture patterns, while only 18% for MTC formations are sensitive, indicating the importance of mid-level moisture is higher for ETC formations. Because of a model dry bias, the simulation of TC formation in an observed environment with lower vorticity but higher moisture is sensitive to the moisture increase through GPS RO data. Sensitivity experiments show that if the moisture in GTS is replaced by that in EPH, the TC formation can be detected in the GTS simulations. In turn, the TC formation cannot be detected in the EPH simulations with GTS moisture. The mechanism causing the difference in simulation performance of TC formation is attributed to more diabatic heating release and stronger positive potential vorticity tendency at mid-levels around the disturbance center caused by the higher moisture magnitudes.


2021 ◽  
Vol 38 ◽  
pp. 00109
Author(s):  
Natalya Savinykh ◽  
Svetlana Shabalkina

On the basis of comparative morphological analysis of the structure of life forms the concept “key biomorph” is offered; it is a mien of a plant which reflects adaptation to the conditions of a definite habitat (a static aspect, a model) and a definite stage in evolutional changes of biomorphs (a dynamical / evolutional aspect). The paper shows a comparative morphological range of key biomorphs in accordance with a monopodial rosette model of shoot formation per gradient of moisture increase in the direction: a floodplain meadow – shores, shore fronts – the water line – a water body. Polygonum bistorta is considered the original key biomorph, changes in it could occur in three lines: 1) Polygonum bistorta – Butomus umbellatus – Nuphar lutea; 2) Polygonum bistorta – Scirpus lacustris – Eleocharis palustris; 3) Polygonum bistorta – Limosella aquatica – Stratiotes aloides. It seems that appearing of secondary-aquatic grasses with a monopodial rosette model of shoot formation was provided by the following modes of morphological evolution: deviation on the shoot level; abbreviation of the bud stage in shoot formation, in forming a part of the shoot (inflorescence), in the anatomic structure of the shoot and the ontogenesis of the original plant; prolongation of the bud phase in shoot development and ontogenesis of the genet.


2020 ◽  
Author(s):  
Alexander Brandt ◽  
Qiqin Zhang ◽  
Maximo Larry Lopez Caceres ◽  
Hideki Murayama

<p>Yamagata prefecture, facing the Japan Sea, is one of the heavy snow fall regions of the world. Around half of the annual precipitation of around 3000 mm falls in winter as snow, producing snow covers of more than three meters depth.  However, air temperature is around 0°C in winter and therefore relatively warm. Hence, snow density becomes 0.5 g/cm³ already early in the snow accumulation phase. To qualify and quantify interactions, three spots on a slope, forested with Japanese cedar (Cryptomeria japonica), have been selected to compare relationships on top, at the middle and at the bottom of snow covered slopes. The site represents the majority of mountain forests in north-eastern Japan. Monitoring soil and air temperature as well as precipitation and soil moisture we found strong interactions between the three hydrological regimes (precipitation, snow cover and soil) in winter. Soil did not freeze and hence volumetric soil moisture content changed during the winter season. Several sharp significant increases of soil moisture have been measured before the snow melt period even started. High rates of soil moisture increase together with an increase of Snow Water Equivalent (SWE) have been found to be caused by rain-on-snow events. In contrast, smaller rates of soil moisture increase in peaks were correlated with a decrease in SWE and therefore a snowmelt process. The interactions of snow cover and soil have been found to be different in the three different spots at the slope. Soil at the bottom of a slope reacts significantly to the highest number of events; soil on the slope reacts only to some events, but more intensively. Thus, most of the water is moving within the snowpack down the slope, increasing the SWE. Thereafter water reaches the soil surface and infiltrates it. This has been found to be also one reason for the formation of depth hoars and therefore the risk of avalanches.</p><p>To conclude, hydrological regimes in north-eastern Japan interact during the whole year due to winter air temperatures around 0°C and soil which does not freeze. The shape of peaks in soil moisture can be used to distinguish between rain and snowmelt causing the soil moisture increase. Various preferential flow patterns at different spots on a slope are an excellent basis for further studies and a basis for further monitoring and modelling. </p>


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