Higher Water Absorption Rate Research Articles

Development and identification of an elite wheat-Hordeum californicum T6HcS/6BL translocation line ND646 containing several desirable traits.

Hordeum californicum (H. californicum, 2n=2X=14, HcHc), one of the wild relatives of wheat (Triticum aestivum L.), harbors many desirable genes and is a potential genetic resource for wheat improvement. In this study, an elite line ND646 was selected from a BC4F5 population, which was developed using 60Co-γ irradiated wheat-H. californicum disomic addition line WJ28-1 (DA6Hc) as the donor parent and Ningchun 4 as the recurrent parent. ND646 was identified as a novel wheat-H. californicum 6HcS/6BL translocation line using genomic in situ hybridization (GISH), fluorescence in situ hybridization (FISH), and H. californicum-specific expressed sequence tag (EST) markers. Further evaluation revealed that ND646 had excellent performance in several traits, such as a higher sedimentation value (SV), higher water absorption rate (WAR), and higher hardness index (HI). More importantly, it had more kernels per spike (KPS), a higher grain yields (GY), and good resistance to powdery mildew, leaf rust, and 2,4-D butylate (2,4-D). Its excellent phenotypic performance laid the foundation for further investigation of its genetic architecture and makes ND646 a useful germplasm resource for wheat breeding.

Review on Properties of Recycled Construction Waste Concrete Aggregate

Recycled construction waste aggregate is to solve the damage caused by construction waste to the natural environment. Through crushing, screening and other processes, the construction waste aggregate is made into reusable coarse aggregate or fine aggregate, and then replaced by natural gravel or natural sand and stone in different replacement rates and applied to the recycled aggregate in concrete. In this paper, three main physical properties of waste concrete, the old ceramic tile, broken ceramic, crushed clay brick and waste glass aggregate are summarized, which are water absorption rate, apparent density and crushing index of recycled building waste aggregate. The crushed clay brick and broken ceramic aggregate have the highest water absorption rate and low in apparent density and high in crushing index. Waste concrete mixture has excessive water absorption, low apparent density and excessive crushing index, whilst damaged ceramic tile combination has low water absorption, low apparent density and low crushing index.

Procena fizičko-mehaničkih osobina kompozita poliester-kukuruz

In this study, corn stalk/polyester composites were prepared using molding techniques at several percentage filler loadings per weight and the physiomechanical properties were studied. The composite showed moderate improvement in tensile strength 13.582MPa for 3% corn stalk which was the highest. The composite also reported the highest values for impact strength 744.90(J/m2 ) and flexural strength 23.947MPa, respectively for filler loading of 3% corn stalk and 93% polyester and 2% corn stalk and 98% polyester composite samples. The significant strengths recorded can be attributed to the good surface intermingling bonding between the corn stalk fillers and the polyester matrix. The study also revealed that, density of the composites decreased with increase in filler loading and the density dropped from 0.116 g/cm3 to 0.108g/cm3 . The composites recorded increase in water uptake with increasing filler loading. The results showed that the highest water absorption rate was at 5% corn stalk loading which had maximum water absorption of 4.55% by the composite samples. The physiomechanical properties of the composites indicate that it can be useful in applications which require moderate strengths. These composites could be considered as a potential way of utilizing agricultural waste materials and as sustainable resources for manufacturing of structural materials such as particle board, partitioning panels, ceiling boards thereby reducing the amount of agricultural wastes and eliminating the pollution caused by burning of corn stalk waste.

Review on Strengthening the Characteristics of Concrete Using Oil Coated Coconut Fibre

Sustainability is a widely acknowledged concept in modern day construction scenario. Although the construction industry is transforming in a substantial way in terms of the material used and the equipment used, the construction cost has risen steeply along with the worse impact on the environment due to this it has resulted in the acceptance of method like the use of natural fiber for example Coconut fibre for improving the strength of concrete. Coconut fiber is easily and widely available in abundance, which makes it fairly sustainable as form of reinforcement material in concrete. The use of coconut fibre as in form of reinforcement has also emerged as new source of income for the coconut producer. In addition, it can also be seen as a new effective way for the discarding of coir mattress wastage. The major problem of coconut fibre i.e. high water absorption rate of the fibre can be reduced to certain extent by coating the fibres with appropriate oil. In addition to this, the fibres which are naturally occurring is also ecologically sustainable and can lower the global carbon track effectively. This study aims to analyse the difference in strength of coconut fibre (processed fibres coated with oil and oil raw fibres coated with oil) reinforced concrete at various fibre contents and to collate it with the traditional concrete. The different strength aspects which are analysed in this study are the tensile, compressive and flexural strength of the concrete reinforced with coconut fibre at different percentages like 4%, 5% & 6% by the weight of cement of fibre. The optimum percentage of the raw fibre meshes and processed fibre were found and the optimum percentage of super-plasticizer required for the desired workability was also examined.

Natural Fiber Reinforced Composite Material for Product Design: A Short Review.

Natural fibers have attracted great attention from industrial players and researchers for the exploitation of polymer composites because of their “greener” nature and contribution to sustainable practice. Various industries have shifted toward sustainable technology in order to improve the balance between the environment and social and economic concerns. This manuscript aims to provide a brief review of the development of the foremost natural fiber-reinforced polymer composite (NFRPC) product designs and their applications. The first part of the manuscript presents a summary of the background of various natural fibers and their composites in the context of engineering applications. The behaviors of NFPCs vary with fiber type, source, and structure. Several drawbacks of NFPCs, e.g., higher water absorption rate, inferior fire resistance, and lower mechanical properties, have limited their applications. This has necessitated the development of good practice in systematic engineering design in order to attain optimized NRPC products. Product design and manufacturing engineering need to move in a mutually considerate manner in order to produce successful natural fiber-based composite material products. The design process involves concept design, material selection, and finally, the manufacturing of the design. Numerous products have been commercialized using natural fibers, e.g., sports equipment, musical instruments, and electronic products. In the end, this review provides a guideline for the product design process based on natural fibers, which subsequently leads to a sustainable design.

Evaluation of Mechanical and Water Absorption Behaviors of Jute/Carbon Fiber Reinforced Polyester Hybrid Composites

ABSTRACT In this work, the influence of hybridizing jute and carbon fibers on the mechanical properties and water absorption behavior of polyester composites was evaluated. The composites were fabricated by using compression molding technique with discrete of overall fiber weight fraction, being pure jute or pure carbon fiber or hybrid. The outcomes of the study revealed that the jute fiber composites have lower mechanical properties and higher water absorption rate when compared with carbon fiber composites. While, the combined effect enhanced the mechanical property (tensile strength of 136.3 MPa, tensile modulus of 3403 MPa, flexural strength of 175.84 MPa, flexural modulus of 9350 MPa and impact strength of 47.43 kJ/m2) and reduced the moisture absorption rate and have good interfacial bonding with polyester which was confirmed in the morphological investigation using scanning electron microscopy. Furthermore, the mechanism of fracture in mechanical-tested samples was observed through scanning electron microscopic images. All the composites developed in the work was followed the Fickian behavior of water absorption.

Mechanical and durability assessment of cement-based and\xa0alkali-activated coating mortars in an aggressive marine environment

Coatings are used as practical solutions against the intrusion of corrosive ions into concrete structures, particularly, in the harsh marine environment. In the present study, the effectiveness of using cement-based and geopolymer-based coatings produced using by-product materials has been evaluated. Silica fume and GGBFS at their optimum dosages were incorporated into mortar mixtures as a cement replacement, and mixtures of NaOH or KOH and sodium silicate solutions were used in the alkali-activated mortars. Shrinkage test, RCMT, and capillary absorption test as common experiments for durability analysis, as well as tests related to the mechanical and bonding properties including compressive strength test, pull-off test, and shear bonding strength test were carried out on the specimens. According to the results, both geopolymer and cement-based mortars improved the compressive and bonding strengths, and chloride diffusion resistance of coatings compared to the OPC mortar. Silica fume was found to be more effective in the strength development of mortars at young ages, while GGBFS was more responsible for acting as a filler and producing further gel in the older ages. The major drawback with geopolymer mortars is the high rate of water absorption and shrinkage coefficient in the early hours, which shows the importance of curing of these mortars at young ages. Overall, the mix design produced with 30% GGBFS and 7.5% silica fume showed the highest durability and mechanical properties and proved to be more compatible with the harsh environment of the Persian Gulf.

Preparation of hydroxybutyl starch with a high degree of substitution and its application in temperature-sensitive hydrogels

In this work, hydroxybutyl starch prepared by acid, alkali, and acid-base synergistic pretreatments from waxy corn starch exhibited great potential for preparing temperature-sensitive hydrogels. The degree of substitution, morphology, and group structure of hydroxybutyl starch were determined. The hydroxybutyl starch prepared by acid-base synergistic pretreatment had the highest degree of substitution. Relative to the native starch, the surface of hydroxybutyl starch particles was smoother and rounder. The formation, microstructure, and properties of temperature-sensitive hydrogels were also determined in this work. The results indicated that the temperature-sensitive hydrogels containing hydroxybutyl starch had irregular pore structures and higher water absorption rates. As the starch content increased, the pore size of these hydrogels increased and then decreased, the water absorption rate increased and the deswelling rate decreased. The equilibrium swelling ratio of the hydrogel prepared by hydroxybutyl starch was greater than that of native starch.

Effect of Cold Plasma Treatment on Cooking, Thermomechanical and Surface Structural Properties of Chinese Milled Rice

Cold plasma (CP) treatment for enhancing functional and cooking properties has been investigated on less rice varieties and delays the industrial adoption of this technology. This study treated three types (short-, medium-, and long-kernel) of milled rice from six Chinese varieties with helium plasma (Radio frequency, 13.56 MHz, 140 Pa) at a combination of watt and time, and evaluated the cooking properties, cooked rice texture, kernel appearance quality, and surface morphology, as well as flour thermal and thermomechanical properties. CP treatment at 120 W for 20 s significantly decreased the cooking time and the hardness of cooked rice while increasing adhesiveness, elasticity, and gruel solid loss. CP did not significantly change the appearance of milled rice, except for chalky rice rate, and kept the peak temperature and enthalpy of gelatinization in rice flour. 120W–20s CP significantly increased rice dough development and stability time, starch gelatinization maximum torque, and starch breakdown, but decreased the stability of protein network and starch retrogradation. As CP power strength increased from 120 to 520 W; the surface rupture of a rice kernel became more severe, and small particles aggregated on the rough surface. Compared with the 0 h sample of 120W–20s CP treatment, the repeating CP treatments at 24 h, 48 h, and 30 d significantly decreased water contact angle and free fatty acid content, but increased water absorption rate and chalky rice rate. These results suggest that 120W–20s helium CP improved the cooking properties of milled rice via leading to the rough kernel surface, higher water absorption rate, weak protein network, and a higher speed of starch gelatinization.

Performance characterization of γ-poly (glutamic acid) super absorbent polymer and its effect on soil water availability

ABSTRACT A novel biodegradable super absorbent polymer (SAP) was synthesized by γ-poly (glutamic acid) (γ-PGA) and poly (ethylene glycol) with the units of glycidyl ether as chain ends (PEGGE). The resultant γ-PGA SAPs with different PEGGE contents were characterized and their effects on soil total available water (TAW) were investigated. The γ-PGA SAP was synthesized at 45 °C for 48 h when γ-PGA was 160 g L−1 (pH = 4.9) and the minimum mass of PEGGE was 20% of the γ-PGA mass. When the PEGGE increased from 20% to 60%, the water absorption rate (WAR) of γ-PGA SAP in distilled water and 0.9% NaCl solution gradually decreased from 651.16 g g−1 to 302.91 g g−1 and from 44.83 g g−1 to 32.9 g g−1 respectively. The γ-PGA SAP with 40% PEGGE had the highest WAR after being reused six times. The field water capacity (FC) and TAW increased with the increasing γ-PGA SAP content; however, when the same amount of γ-PGA SAP was added to the soil, the FC and TAW in the soil gradually decreased with the increasing PEGGE in the γ-PGA SAP. The γ-PGA SAP with a proportion of 0.15% in the soil presented the largest soil WAR.

RETRACTED: Simulation of microbial enhanced recycled aggregate preparation system based on artificial intelligence and embedded processor

Construction waste recycling is prevented by its high water absorption rate and the weak bond of the new cement paste. This problem is exacerbated by the fact that Requirements for Accreditation Scheme (RFAS) recycled porridge production. To explore the possibility of repeated use of the RFAS system, it is proposed in the integrated study of Microbial Carbonate Precipitation (MCP) derived from RFAS. Due to its rapid construction, the demand for concrete raw materials, especially coarse aggregates, increases the risk of premature erosion of natural resources. Alternative energy sources for raw materials delay the possibility of this initial exhaustion. Recycled Coarse Aggregate (RCA) played an important role as a ready-mixed concrete substitute. Natural Coarse Aggregate (NCA) changes. Previous studies have shown that RCA's special reinforcing concrete lags behind NCA. I hope that may be due to the microstructure of the calcium carbonate hailstone. Recycling aggregate has high water absorption and crushing indicators. In recent years, the integrated cycle has changed the new treatment model biopsy. Degradation-enhanced protocols have been implemented to change the nature of the motor in circulation. Famous for using the information protocol learning machine based on extracting and source information, it comes on a hardware platform provided that vendors compete between the FPGA and the GPU to run intensive computational learning algorithms quickly and efficiently. Deep learning, which is considered to be the key point by which drivers compare the most advanced machine learning applications.

Dimensional and Thermal Reliability of Multi-Walled Carbon Nanotube Filled Natural Rubber Nanocomposites

The exceptional mechanical and thermal properties, conceivable with carbon nanotubes (CNTs) make a distinction of them as excellent choices for natural rubber nanocomposite reinforcement. Nigeria, in recent years, has been awash with foreign prostheses, many of which fail to meet the criteria of the International Society of Prosthetics and Orthotics (ISPO) for developing countries. However, there are major marked gaps that make them susceptibility to premature failure and dimensional instability, caused by a high rate of water absorption in a humid environment; owing to the dynamic nature of human gait. This paper critically examines the effect of water absorption, thermogravimetric and dynamic mechanical properties, on carbon nanotube-reinforced natural rubber nanocomposite (NC) for prosthetic foot application. CNTs were synthesised via catalytic chemical vapour deposition (CCVD) technique and the NCs were produced by using an electrically heated hydraulic press. Thermogravimetric analysis (TGA), water absorption rate and dynamic mechanical analysis (DMA) of the nanocomposites were carried out with a view to comparing the various compositions used in this paper. Of the five NCs developed (NR/MWCNT-0, NR/MWCNT-3, NR/MWCNT-6, NR/MWCNT-9, NR/MWCNT-12 and NR/MWCNT-15), NR/MWCNT-3 (3 g of MWCNT in 100 g of natural rubber) showed the highest thermal stability of 260 °C, optimal water absorption rate of 0.1% and highest quality energy storage and dissipation capacity, as indicated by 2.239 DMA loss factor curve amplitude, hence giving it a comfortable edge over its existing counterparts. The results of the various analyses carried out indicated, therefore, that reinforcing natural rubber with multi-walled carbon nanotube offers a reliable alternative material for the prosthetic industry.

Effect of wheat flour particle size on the quality of fresh white salted noodles

Quality of fresh white salted noodles (WSNs) made of wheat flour with three different particle size was investigated. Water distribution, free sulfhydryl, secondary structure, and molecular weight distribution of protein, cooking property, texture property, and organoleptic property of WSNs were analyzed to elucidate quality changes induced by different flour particle sizes. WSNs of fine flour (D90: 55.82 μm) had higher brightness and bound water proportion. WSNs of fine flour had long optimum cooking time (2.42 min), high cooking yield (175.63%), and cooking loss (13.44%), and it had high hardness (5,672.2 g) and chewiness (4,078.15). Microstructure observation exhibited that a stronger and more resistant network existed in the WSNs of the finest flour. Furthermore, the WSNs made of the finest flour has the highest score in sensory evaluation. Wheat flour with small particle size (D90: 55.82 μm) could provide a beneficial effect on the quality improvement of WSNs. Practical applications Producing finer wheat flour requires more energy, more equipment attrition, and more production costs. However, wheat flour factory tend to produce finer grain flour for Chinese consumers' preference for bright white wheat flour. In this study, three kinds of wheat flour with different particle sizes were prepared using milling, and their particle size were distributed in three ranges (D90: 103.0, 66.8, and 55.8 µm). It was found that wheat flour with small particle size (D90: 55.8 μm) had a higher water absorption rate and formed a more stable dough. The fresh white salted noodles of fine flour had a tight interior structure, high water absorption rate, low cooked breaking ratio, better texture performance, and the high total score in sensory evaluation. Therefore, fine wheat flour are more suitable for processing fresh white salted noodles.

Effects of wheat flour particle size on physicochemical properties and quality of noodles.

The effect of particle size on the physicochemical and noodle quality of wheat flours was investigated. Granular wheat flour was ground by adjusting the distance between the rolls (0.02, 0.04, 0.06, 0.08, and 0.1mm) of the flour mill to obtain wheat flour in five different particle sizes. The results showed that milling intensity significantly reduced the particle size and increased the damaged starch content and sedimentation value, but there were no significant differences in protein or ash contents. The reduction of wheat flour particle size significantly decreased the peak viscosity, trough viscosity, final viscosity, breakdown, and setback of the blends, while there were no significant differences in pasting temperature. Stress relaxation characteristics indicated that as the particle size of wheat flour decreased, dough hardness increased. The noodles made from wheat flour with a smaller particle size had a higher water absorption rate and cooking loss rate. Textural profile analysis parameters showed that as the particle size of wheat flour decreased, the hardness, chewiness, recovery, and adhesiveness of noodles showed increasing trends, and there was no significant difference in elasticity. In summary, it is found that the quality of the noodles made by sample C (D50 : 78.47µm) is better.

STUDY OF HYDROTHERMAL TREATMENT OF DRIED MALT WITH PLASMOCHEMICALLY ACTIVATED AQUEOUS SOLUTIONS

Studying the specific technological features and functional properties of foodstuffs made with the addition of malt is a particular priority for scientists and experts in the food processing industry. The paper deals with the peculiarities of malt processing, namely, with how it is humidified by means of plasmochemically activated aqueous solutions with different concentrations of hydrogen peroxides. The study presented deals with hydrothermal treatment of dry malt with solutions activated by the action of non-equilibrium contact plasma. In the course of this treatment, microparticles of hydrogen peroxide are formed. When in contact with the raw materials, they can form active oxygen, which is an agent stimulating biochemical transformations that activate the mashing and extraction of malt. The hydrogen peroxide concentration has been determined for the solutions used for further hydrothermal treatment of malt. It has been established which modes of hydrothermal treatment of dry germinated barley grain with plasmochemically activated aqueous solutions ensure the fastest absorption of moisture by malt. The highest water absorption rate was observed in the samples with activated water where the peroxide concentration was 600mg/l. It has been studied how the degree of malt swelling changed with the temperature and mash ratio. When ordinary water was used, the optimum mash ratio was 1:4 (65°С), and with activated water, a similar result was obtained with the mash ratio 1:3, which allows reducing water consumption in the process. The process of malt mashing has been studied, and the malt extracting capacity analysed. When plasmochemically activated aqueous solutions were used, the extracting capacity was observed to be increasing noticeably by 0.06–0.41%, depending on the mashing mode. It has been proved that the antiseptic properties of the activated water allow extra disinfection of raw materials. Using activated aqueous solutions reduces pathogen contamination of grain. It has been found that absolute destruction of mould microflora is possible at high concentrations of peroxides in the solutions. The paper highlights the operational parameters that can be used during industrial processing of malt, and gives recommendations for the use of plasmochemically activated aqueous solutions in barley malt processing.

Bacterial cellulose as reinforcement in paper made from recycled office waste pulp

Bacterial cellulose, produced during fermentation of Kombucha tea, was investigated relative to its ability to modify the characteristics of pulp from recycled office wastepaper. The produced bacterial cellulose wet films were dispersed and added rates of 5%, 10%, and 15% to the recycled office wastepaper. The Fourier-transform infrared spectroscopy analyses, scanning electron microscopy images and thermogravimetric analysis values were determined in order to characterize the pulp samples. The results of these analyses showed similar changes as the amount of added bacterial cellulose increased, which also meant an increased amount of filler attaching to the fiber matrix. The burst index and tensile index values were protected while the tear index value partially decreased as the amount of added bacterial cellulose increased. The brightness values of the bacterial cellulose reinforced papers did not change after thermal aging, while the changes in the yellowness values were quite limited. Higher water absorption rates, and lower air permeability values were obtained from bacterial cellulose reinforced recycled office wastepaper sheets, which corresponded to the addition of increased bacterial cellulose amounts. Considering the mechanical and physical properties of the reinforced paper, bacterial cellulose represents a promising alternative for the reinforcement of office wastepaper.

Effects of the addition of waxy and normal hull-less barley flours on the farinograph and pasting properties of composite flours and on the nutritional value, textural qualities, and in vitro digestibility of resultant breads.

Hull-less barley (HLB), especially waxy HLB, contains many physiologically active ingredients; however, its poor processing performance and end-product quality are unfavorable. In this study, 80% waxy or normal HLB wholegrain flour (WGF) and 20% wheat flour were used for baking bread. The farinograph and pasting properties of composite powders, and the nutritional value, textural properties, and in vitro hydrolysis of resultant breads were evaluated. The addition of a high proportion of HLB WGFs significantly increased the nutritional value of breads, especially the β-glucan contents of waxy HLB breads. The addition of HLB WGFs and a suitable amount of wheat gluten led to a lower degree of softening of HLB bread flours but improved its farinograph characteristics, such as higher water absorption rate, development time, stability time, and farinograph quality number. Although the sensory profiles of HLB breads were considerably lower than those of wheat bread, they still received a good overall acceptability from a panel of sensory evaluators. HLB breads, particularly the waxy types, exhibited higher hardness, gumminess, chewiness, and lower specific volume, glycemic index and equilibrium concentration in starch hydrolysis. After baking, the starch crystallinity of dough changed from A to V type, and the relative crystallinity decreased. Overall, waxy HLB breads had more nutritional value than normal HLB breads. Higher β-glucan and total dietary fiber content in HLB might have a positive effect on the nutritional value of the resultant breads. However, high β-glucan and total dietary fiber was also accompanied by a negative effect on the sensory quality and processing performance of the end product. PRACTICAL APPLICATION: The composite flour with 80g hull-less barley wholegrain flour, 20g wheat flour, and 30g wheat gluten can be substituted in breadmaking. Compared to wheat bread, hull-less barley bread exhibited different but acceptable sensory properties and had more nutritional value, particularly the waxy one. Therefore, a high proportion of hull-less barley could be recommended for bread production.

Physical and Chemical Characteristics of Rice Straw

This study aims to determine the physical characteristics of rice straw and highlights the presence of sugar in rice straw. The use of natural fibers as a reinforcement in construction has existed for millennia. They are mixed with clay to make building materials. This addition avoids cracks and sometimes contributes to flexural strength. Researchers have detected a high level of sugar in natural fibers. This sugar contained in the biomass is at the origin of the setting delay and the hardening of the building materials. Another not least significant defect found in natural fiber is its high water absorption potential. This hydrophilic character is due to the intrinsic porosity of the straws. This article aims to determine the physical characteristics of rice straw and highlights the presence of sugar in rice straw. First, the density and water absorption rate of the rice straw were determined. Then chemical tests were carried out to determine the rate of mineral constituents (ash), lignin, hemicellulose and finally the rate of cellulose is deduced. Like most crop straws, rice straw contains a high level of sugar. It also has a very low density compared to other building materials. It is around 450 kg/m3. Rice straw also has a high water absorption rate. The absorption rate absorption rate (At) 5 min of immersion in water, its absorption rate reaches 234%.

Influence of Soybean Hull Fiber Concentration on the Water Absorption and Mechanical Properties of 3D-Printed Thermoplastic Copolyester/Soybean Hull Fiber Composites

In this work, fused filament fabrication 3D-printed parts of soybean hull fiber thermoplastic copolyester (TPC) composites with soybean hull fiber concentrations of 0-35 wt.% were tested to understand the influence of mechanical properties and moisture sensitivity on the soybean hull fiber concentration. The composites were analyzed for their microstructures and mechanical properties in as-printed condition and after immersion in deionized water for 168 h. The printed parts with ≥ 25 wt.% soybean hull fiber were found to have more porosity (9-12%) leading to high rate of water absorption with a maximum weight gain of ~ 8% and up to 4% volumetric swelling. However, in the as-printed condition, these composites exhibited significantly higher elastic modulus of 80 ± 3 MPa than pure TPC (36 ± 3 MPa) and their strength improved by 40%. The toughness of the composites decreased below that of pure TPC when the fiber concentration was 35 wt.% due to significant drop in the elongation. The composites with ≤ 15 wt.% soybean hull fiber showed marginal drop in the mechanical properties due to water absorption. Additionally, the microstructural analysis showed good fiber–matrix interfacial characteristics in as-printed condition, which were damaged due to moisture absorption in addition to defragmentation of fiber bundles. Interestingly, the toughness of TPC–soybean hull fiber composites was immune to water absorption and the deleterious effect of moisture on the mechanical appears to be partly reversible after drying the composites.

Hydrological functions of litters under five typical plantations in southern and northern mountains of Lanzhou City, Northwest China

Combined with field observation and indoor water immersion test, water holding characteristics of litters from five typical plantations (Platycladus orientalis, Robinia pseudoacacia, Populus alba var. pyramidalis, P. orientalis+R. pseudoacacia, P. alba var. pyramidalis+R. pseudoacacia) in southern and northern mountains of Lanzhou City were examined. Results showed that litter mass under the plantations ranged from 13.50 to 47.01 t·hm-2, with an order of P. alba var. pyramidalis+R. pseudoacacia＞P. orientalis+R. pseudoacacia＞P. orientalis＞R. pseudoacacia＞P. alba var. pyramidalis. The percentage of un-decomposed litters was greater than that of semi-decomposed litters in all plantations except for P. orientalis plantations. The maximum water-holding rate of litters ranged from 190.8% to 262.7%, with the greatest value in the P. alba var. pyramidalis+R. pseudoa-cacia and the lowest in P. orientalis plantations. The maximum water-holding capacity of litters was 35.29-123.59 t·hm-2, with an order of P. alba var. pyramidalis+R. pseudoacacia＞P. orientalis+R. pseudoacacia＞R. pseudoacacia＞P. orientalis＞P. alba var. pyramidalis. Litter water absorption rate declined linearly within the first hour, and then decreased slowly. Semi-decomposed litters had a higher water-absorption rate than un-decomposed litters. The maximum water retaining amount and effective retaining amount of the litters were P. alba var. pyramidalis+R. pseudoacacia＞P. orientalis+R. pseudoacacia＞P. orientalis＞R. pseudoacacia＞P. alba var. pyramidalis. P. alba var. pyramidalis+R. pseudoacacia had the highest effective retaining rate. P. alba var. pyramidalis+R. pseudoacacia plantation had highest capacity for soil and water conservation in southern and northern mountains of Lanzhou City.