Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to...Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to study their physical,chemical,and mechanical properties.In this context,the present study relates to the extraction,characterization,and optimization of Typha angustata L.stem fibers.For this purpose,desirability functions and response surface methodology were applied to simultaneously optimize the diameter(D),linear density(LD);yield(Y),lignin fraction(L),and tenacity(T)of Typha stem fibers.Typha stems have been subjected to both alkali(NaOH)and enzymatic(pectinex ultra-SPL)treatments.Three levels of process variables including enzyme concentration(10,15,and 20 ml/L)and treatment duration(10,15,and 20 days)were used to design the experiments according to the factorial design.Experimental results were examined by analysis of variance and fitted to second order polynomial model using multiple regression analysis.The Derringer’s desirability function released that the values of process variables generating optimized diameter,linear density,yield,lignin ratio and tenacity are 20 ml/L and 20 days for concentration of pectinex ultra-SPL enzyme and treatment duration,respectively.Confirmation was performed and high degree of correlation was found between the experimental and statistical values.Moreover,the morphological structure has been investigated by the scanning electron microscope,showing a crenelated structure of ultimate fiber bundles of cellulose composing the Typha fiber.Compared to Typha stem non-treated fibers(TSNTF),Typha stem combined treated fibers(TSCTF),brings to improve mechanical properties.This change in mechanical properties is affected by modifying the fiber structure showing alpha cellulose of(66.86%)and lignin ratio of(10.83%)with a crystallinity index of(58.47%).展开更多
The application potential of cellulosic materials in natural composites and other fields needs to be explored to develop innovative, sustainable, lightweight, functional biomass materials that are also environmentally...The application potential of cellulosic materials in natural composites and other fields needs to be explored to develop innovative, sustainable, lightweight, functional biomass materials that are also environmentally friendly. This study investigated Typha angustifolia (Typha sp.) as a potential new raw material for extracting cellulose nanocrystals (CNCs) for application in wastewater treatment composites. Alkaline treatments and bleaching were used to remove cellulose from the stem fibres. The CNCs were then isolated from the recovered cellulose using acid hydrolysis. The study showed a few distinct functional groups (O-H, -C-H, =C-H and C-O, and C-O-C) in the Fourier Transform Infrared (FTIR) spectra. A scanning electron microscope (SEM) revealed the smooth surface of CPC and CNCs, which resulted from removing lignin and hemicellulose from powdered Typha angustifolia. Based on the crystalline index, the powdered Typha angustifolia, CPC, and CNCs were 42.86%, 66.94% and 77.41%. The loss of the amorphous section of the Typha sp. fibre resulted in a decrease in particle size. It may be inferred from the features of a Typha sp. CNC that CNCs may be employed as reinforcement in composites for wastewater treatment.展开更多
This work focuses on the design of a new type of eco-material based on Typha“Domingensis”and clay from the south of the Republic of Benin through various dosages.Three particle size classes of typha shavings were se...This work focuses on the design of a new type of eco-material based on Typha“Domingensis”and clay from the south of the Republic of Benin through various dosages.Three particle size classes of typha shavings were selected to be mixed with two types of clayin order to make parallelepiped shaped samples ready for experimentation.The massive use of these briquettes thus obtained,in the construction of habitats,would not only contribute to reducing the energy consumption inside the dwellings but also would limit the invasion of the waterways of Benin,which would facilitate navigation,fishing and river sanitation activities.In addition,this biosourced,low-polluting material would contribute to improving the energy transition by integrating it into rehabilitation of buildings.展开更多
Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate disp...Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate displayed most significant effects on the suspended matter (P 〈 0.01), with the reduction of 76%-87% and 52%--63% for P. australis, and 83%-86% and 45%-62% for T. orientalis in gravel substrate and sediment substrate, respectively. Both species and substrates significantly decreased the N and P concentrations of water body (P 〈 0.01). P. australis showed higher total N and P concentrations in tissues than T. orientalis and had a greater potential to remove nutrients from the lake. Phosphate was easily to concentrate in the belowground tissues, while nitrate concentration was higher in leaf and stalk. Therefore, harvesting the aboveground tissues could take most of nitrate out of the sediment. The saturate photosynthetic rate (Asat) of P. australis was higher than that of T. orientalis when grown in sediment substrate. But instance water-use- efficiency (WUEi) (A/E) and intrinsic water use efficiency (A/gs) showed the maximum values of two species grown in river water. With significant difference in gs, however, intercellular CO2 concentration (Ci) had no obvious difference in two species which indicated that high Asat value of P. australis might result from the increased carboxylation capacity of the mesophyll, because of the central role of N in photosynthetic enzymes. Our findings suggest that the plants could absorb most of nitrogen in polluted water, while gravel displayed a high capacity for absorbing the suspended matters and phosphate salts. Therefore, biological and physiological pathways for pollutant removal should be integrated.展开更多
Chemical investigation of the pollen of Typha angustifolia Linn.has led to the isolation of two new nonacosanetriols,7,8,10- nonacosanetriol(1) and 7,9,10-nonacosanetriol(2).Their structures were elucidated by chemica...Chemical investigation of the pollen of Typha angustifolia Linn.has led to the isolation of two new nonacosanetriols,7,8,10- nonacosanetriol(1) and 7,9,10-nonacosanetriol(2).Their structures were elucidated by chemical reaction and spectral analysis. Compounds 1 and 2 exhibited weak activity of antiplatelet aggregation in vitro.展开更多
Here,we report the mechanical and water sorption properties of a green composite based on Typha latifolia fibres.The composite was prepared either completely binder-less or bonded with 10%(w/w)of a bio-based resin whi...Here,we report the mechanical and water sorption properties of a green composite based on Typha latifolia fibres.The composite was prepared either completely binder-less or bonded with 10%(w/w)of a bio-based resin which was a mixture of an epoxidized linseed oil and a tall-oil based polyamide.The flexural modulus of elasticity,the flexural strength and the water absorption of hot pressed Typha panels were measured and the influence of pressing time and panel density on these properties was investigated.The cure kinetics of the biobased resin was analyzed by differential scanning calorimetry(DSC)in combination with the iso-conversional kinetic analysis method of Vyazovkin to derive the curing conditions required for achieving completely cured resin.For the binderless Typha panels the best technological properties were achieved for panels with high density.By adding 10%of the binder resin the flexural strength and especially the water absorption were improved significantly.展开更多
A molecular biology method, fluorescent in situ hybridization(FISH), in which the pre-treatment was improved in allusion to the media of the constructed wetlands(CW), e.g. the soil and the grit, was used to invest...A molecular biology method, fluorescent in situ hybridization(FISH), in which the pre-treatment was improved in allusion to the media of the constructed wetlands(CW), e.g. the soil and the grit, was used to investigate the vertical distribution characteristics of ammonia-oxidizing bacteria(AOB) quantity and the relation with oxidation-reduction potential(ORP) in the Typha latifolia constructed wetlands under three different Ioadings in summer from May to September. Results showed that the quantity of the AOB decreased in the Typha latifolia CW with the increase of vertical depth. However, the AOB quantity was 2-4 times the quantity of the control in the root area. Additionally, ORP in the rhizosphere was found to be higher than other areas, which showed that Typha latifolia CW was in an aerobic state in summer when using simulated non-point sewage at the rural area of Taihu Lake in China and small town combined sewage.展开更多
To probe the influence and the adverse-resistance characteristics of wetland plants in presence of silver nanoparticles (AgNPs), the changes in the physiological and biochemical characteristics (including the superoxi...To probe the influence and the adverse-resistance characteristics of wetland plants in presence of silver nanoparticles (AgNPs), the changes in the physiological and biochemical characteristics (including the superoxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity, soluble protein content, and chlorophyll content) of Typha orientalis exposed to different concentrations of AgNPs solutions (0, 0.1, 1, 20 and 40 mg/L) were explored. Meantime, the accumulation of silver content in these plants was revealed. The results show that under low concentrations of AgNPs, the SOD and POD activities in the leaves of Typha orientalis are strengthened to different degrees. However, high concentrations of AgNPs inhibit the activities of SOD and POD. Under the stress of different concentrations of AgNPs, the CAT activities are inhibited initially and later recovered to some extent. Under the stress of low concentrations of AgNPs, the soluble protein content in the leaves of Typha orientalis increases significantly, but decreases more significantly with increasing concentrations of AgNPs. Low concentrations of AgNPs promote chlorophyll synthesis in the leaves of Typha orientalis , but the chlorophyll content subsequently falls to pre-stress levels. In contrast, high concentrations of AgNPs cause a certain inhibition to generate chlorophyll. Meanwhile, the results show that the silver concentrations of plant tissues increase with the exposure of concentrations of AgNPs and they have a positive relationship with the exposure of concentrations of AgNPs.展开更多
Convective heat transfer coefficients, materializing exchanges between solid wall (here typha) and its environment, influence its behavior under excitation pulse. Temperature of wall and its density of flow vary with ...Convective heat transfer coefficients, materializing exchanges between solid wall (here typha) and its environment, influence its behavior under excitation pulse. Temperature of wall and its density of flow vary with these coefficients according to its thickness (in depth). This study therefore focuses on the evaluation of convective heat transfer coefficient on front face and the optimal insulation thickness.展开更多
Three polysaccharides, TAA, TAB, TAC have been isolated from the pollen of Typha angustifolia L. , and purified by hot water extraction, alcohol precipitation, Sevage method, gel filtration (Sephadex G50) and ion-exch...Three polysaccharides, TAA, TAB, TAC have been isolated from the pollen of Typha angustifolia L. , and purified by hot water extraction, alcohol precipitation, Sevage method, gel filtration (Sephadex G50) and ion-exchange chromatography on DEAE Sephadex A25 and DEAE-cellulose. Their purities were tested by gel filtration and electrophoresis. Their structures were characterized by paper chromatography of the hydrolysis products, GLC analysis of the alditol acetates, alkylation analysis, 1H NMR and 13C NMR spectra. TAA is mainly composed of a-L-arabinofuanose, β-D-galactose and α-D-galacturonic acid, while the backbones of TAB and TAC are composed of (1→5)-linked α- L-arabinofuranosyl residues.展开更多
The aim of this study was to determine the species composition, biodiversity and, relative abundance of epiphytic algae and their relationship with environmental variables on Typha latifolia and Phragmites australis a...The aim of this study was to determine the species composition, biodiversity and, relative abundance of epiphytic algae and their relationship with environmental variables on Typha latifolia and Phragmites australis at Lake Gala(National Park). Epiphytic algae were gathered monthly by collecting aquatic plants between March 2014 and November 2014. In the epiphytic flora were a total of 133 taxa were identified, 107 taxa were identified on T. latifolia and 96 were discovered on P. australis. While the mean species richness, species diversity and evenness values of the algae identified on T. latifolia were 46, 1.85 and 0.51 respectively, these values were respectively 43, 1.51 and 0.43 on P. australis. While diatoms were generally dominant, other dominant groups in the epiphytic flora included green algae and blue-green algae. The algae that had the highest relative biovolume on T. latifolia were Spirogyra affinis, Oscillatoria sancta and Gomphonema acuminatum, while the algae that had the highest relative biovolume on P. australis were E pithemia adnata, Oscillatoria sancta and R hopalodia gibba. Results show that species composition of epiphytic algae was different, but diversity values were similar on all the macrophytes. The hydrological pulse is one of the most important factors determining the physical and chemical environment of the epiphytic algal community. It was found that some environmental factors were highly eff ective on community distribution in the epiphyton. Additionally, it was observed that some epiphytic algae species had a substrate preference between T. latifolia and P. australis.展开更多
Typha shuttleworthii is the semi-aquatic plant in the modern areal which embraces mainly the ocean districts of Europe. The eastern border of the area of this species is located in Eastern Europe on the territory of V...Typha shuttleworthii is the semi-aquatic plant in the modern areal which embraces mainly the ocean districts of Europe. The eastern border of the area of this species is located in Eastern Europe on the territory of Vyatka-Kama Cis-Urals (VKCU). Almost everywhere species is considered rare and is included in the Red Data Books in many European countries. However, on the territory of Russia, T. shuttleworthii is not protected. The rarity of this species makes it necessary to study its natural populations for their protection. In the paper, we present the materials on some biological and ecological features of the Typha shuttleworthii, growing on the territory of Vyatka-Kama Cis-Urals, where the species is represented by its extreme eastern populations. This species is offered to the protection on the territory of the European part of Russia within the Republic of Tatarstan and Udmurtia.展开更多
Three polysaccharides TAA,TAB and TAC were purified from the pollen of Typha An- gustifilia L..TAA is mainly composed of α-L-arabinofuranose,β—D—galactose and α—D—galac- turonic acid.TAB and TAC contain the bac...Three polysaccharides TAA,TAB and TAC were purified from the pollen of Typha An- gustifilia L..TAA is mainly composed of α-L-arabinofuranose,β—D—galactose and α—D—galac- turonic acid.TAB and TAC contain the backbone mainly composed of (1→5)—linked—L—arabi- nosyl residue.展开更多
Plant-based concretes are produced from plant aggregates and a binder.Plant fibers are mainly composed of saccharides(sugars)and these sugars can decrease the concentration of Ca2+ions in the cement pore solution and ...Plant-based concretes are produced from plant aggregates and a binder.Plant fibers are mainly composed of saccharides(sugars)and these sugars can decrease the concentration of Ca2+ions in the cement pore solution and delay the formation of hydration products.To improve the interfacial bond between fibers and matrix a chemical treatment is widely used.This study investigates the effect of sodium hydroxide treatment on physical and hygroscopic properties of Typha aggregates.In particular,a 5%sodium hydroxide solution is used to treat these aggregates and their bulk and absolute densities,porosity,water content and water absorption are evaluated accordingly.Results indicate that bulk and absolute densities increase after treatment from 56.44 kg/m^(3) to 122.57 kg/m^(3) and 541.93 kg/m^(3) to 555.17 kg/m^(3),respectively.NaOH treatment reduces porosity of Typha from 89.58%to 77.92%and decreases water content from 1.4%to 1%.The treatment with sodium hydroxide reduces substantially the water absorption of the aggregates.展开更多
A greenhouse study was conducted on phytoextraction and accumulation of lead (Pb) and cadmium (Cd) from contaminated soil – water microcosms by the narrow-leaved cattail, Typha angustifolia. The plants were grown in ...A greenhouse study was conducted on phytoextraction and accumulation of lead (Pb) and cadmium (Cd) from contaminated soil – water microcosms by the narrow-leaved cattail, Typha angustifolia. The plants were grown in sandy loam soil containing 1,666 and 38.5 mg/L of Pb(NO3)2 and Cd(NO3)2 respectively. The trends of lead and cadmium by T. angustifolia for all soil – water microcosms suggested interaction effects as decreased soil lead concentrations and increased water cadmium concentrations over time. T. angustifolia expressed trends as increased biomass in all contaminated shoots and roots examined. Cadmium uptake in shoot and root biomass slightly decreased when lead was initially added to the soil but cadmium uptake in root biomass increased after 30 days. Data suggested an interaction between lead and cadmium and possible that lead uptake was inhibited when cadmium was present.展开更多
The construction industry in Senegal is experiencing an upsurge in the development of residential housing units and administrative buildings within the new Diamniadio municipality, an area located just about 35 km fro...The construction industry in Senegal is experiencing an upsurge in the development of residential housing units and administrative buildings within the new Diamniadio municipality, an area located just about 35 km from the capital city of Dakar. Laboratory oedometer or expansive-index tests, however, show poor density and compromised shear strength in the soil samples within the area -posing serious construction problems due to significant volume changes (swellings) that occur when subjected to moisture, thus, bringing into question the structural performance integrity of the soil, and the financial implications of substitute soil types used to compensate for its poor tensile strength. By way, the companies collect the soil of this location (Diamniadio) and throw it to make pile or micro-pile (pious) for their structures. This article demonstrates how we can value the soil of Diamniadio and the Typha Australis in residential building with a reasonable cost. Typha Australis is a plant generally luxuriant within the northern and central belts of Senegal but also known for its negative ecological impacts on the agricultural production of rice. The valorisation of the soil of Diamniadio will pass by the ability to increase its stability or to decrease its shrinkage/swelling rate. When we achieve it, the soil associate with Typha Australis will be used for small bricks which can be useful for partition wall and so the soil will not be ever thrown as a non-useful material. Tests results of soil specimens extracted from the site show a shrinkage rate of 29.19% with estimated cracking depths of 3.5 cm. But by adding gradually Typha Australis, the shrinkage rate will pass from 29.19% to 5.13% with the material treats with 10% by mass of Typha Australis. Moreover, the crackings in the cylindrical specimen disappear. That shows the increase of the stability;thus the composition will be used for building bricks. However, the densities will also be affected by the presence of Typha Australis. The density is decreased from 2032.28 Kg/m<sup>3</sup> for the soil without Typha Australis to 937 Kg/m<sup>3</sup> for the one with 10% of Typha Australis.展开更多
Energy consumption in the building sector is constantly increasing and represents more than 44% in the residential and tertiary sectors in many <span><span style="font-family:Verdana;">countries&...Energy consumption in the building sector is constantly increasing and represents more than 44% in the residential and tertiary sectors in many <span><span style="font-family:Verdana;">countries</span><span style="color:#C45911;"> </span></span><span style="font-family:Verdana;">[1]</span><span></span><span><span></span></span><span style="font-family:Verdana;">. Thus, the building represents a real possibility of energy saving and is the subject of several studies particularly in actual context of experimentation</span><span style="font-family:Verdana;"> with materials based on plant fibers (hemp, flax, millet wastage, etc.). These biobased materials such as typha have shown real interest in the buildings construction due to their light and porous nature. It’s in this context that we were interested in typha australis mixed with classic aggregates (cement, sand, gravel 3/8) to make typha’s concrete. On this concrete, we carried out experimental measurements in order to better understand its contributions in the building. The interesting results obtained show that typha australis, which is an invasive and harmful grass, can be valued and integrated among local building materials in the form of typha’s concrete in order to improve the energy efficiency of buildings.</span>展开更多
文摘Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to study their physical,chemical,and mechanical properties.In this context,the present study relates to the extraction,characterization,and optimization of Typha angustata L.stem fibers.For this purpose,desirability functions and response surface methodology were applied to simultaneously optimize the diameter(D),linear density(LD);yield(Y),lignin fraction(L),and tenacity(T)of Typha stem fibers.Typha stems have been subjected to both alkali(NaOH)and enzymatic(pectinex ultra-SPL)treatments.Three levels of process variables including enzyme concentration(10,15,and 20 ml/L)and treatment duration(10,15,and 20 days)were used to design the experiments according to the factorial design.Experimental results were examined by analysis of variance and fitted to second order polynomial model using multiple regression analysis.The Derringer’s desirability function released that the values of process variables generating optimized diameter,linear density,yield,lignin ratio and tenacity are 20 ml/L and 20 days for concentration of pectinex ultra-SPL enzyme and treatment duration,respectively.Confirmation was performed and high degree of correlation was found between the experimental and statistical values.Moreover,the morphological structure has been investigated by the scanning electron microscope,showing a crenelated structure of ultimate fiber bundles of cellulose composing the Typha fiber.Compared to Typha stem non-treated fibers(TSNTF),Typha stem combined treated fibers(TSCTF),brings to improve mechanical properties.This change in mechanical properties is affected by modifying the fiber structure showing alpha cellulose of(66.86%)and lignin ratio of(10.83%)with a crystallinity index of(58.47%).
文摘The application potential of cellulosic materials in natural composites and other fields needs to be explored to develop innovative, sustainable, lightweight, functional biomass materials that are also environmentally friendly. This study investigated Typha angustifolia (Typha sp.) as a potential new raw material for extracting cellulose nanocrystals (CNCs) for application in wastewater treatment composites. Alkaline treatments and bleaching were used to remove cellulose from the stem fibres. The CNCs were then isolated from the recovered cellulose using acid hydrolysis. The study showed a few distinct functional groups (O-H, -C-H, =C-H and C-O, and C-O-C) in the Fourier Transform Infrared (FTIR) spectra. A scanning electron microscope (SEM) revealed the smooth surface of CPC and CNCs, which resulted from removing lignin and hemicellulose from powdered Typha angustifolia. Based on the crystalline index, the powdered Typha angustifolia, CPC, and CNCs were 42.86%, 66.94% and 77.41%. The loss of the amorphous section of the Typha sp. fibre resulted in a decrease in particle size. It may be inferred from the features of a Typha sp. CNC that CNCs may be employed as reinforcement in composites for wastewater treatment.
文摘This work focuses on the design of a new type of eco-material based on Typha“Domingensis”and clay from the south of the Republic of Benin through various dosages.Three particle size classes of typha shavings were selected to be mixed with two types of clayin order to make parallelepiped shaped samples ready for experimentation.The massive use of these briquettes thus obtained,in the construction of habitats,would not only contribute to reducing the energy consumption inside the dwellings but also would limit the invasion of the waterways of Benin,which would facilitate navigation,fishing and river sanitation activities.In addition,this biosourced,low-polluting material would contribute to improving the energy transition by integrating it into rehabilitation of buildings.
基金supported by the Control and Treatment of Water Pollution Implementation Scheme of the National Important Science and Technology Project(No. 2008ZX07526-002)the Hi-Tech Research and Development Program (863) of China (No. 2002AA601012-06)the National Basic Research Program (973) of China (No. 2002CB412409)
文摘Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate displayed most significant effects on the suspended matter (P 〈 0.01), with the reduction of 76%-87% and 52%--63% for P. australis, and 83%-86% and 45%-62% for T. orientalis in gravel substrate and sediment substrate, respectively. Both species and substrates significantly decreased the N and P concentrations of water body (P 〈 0.01). P. australis showed higher total N and P concentrations in tissues than T. orientalis and had a greater potential to remove nutrients from the lake. Phosphate was easily to concentrate in the belowground tissues, while nitrate concentration was higher in leaf and stalk. Therefore, harvesting the aboveground tissues could take most of nitrate out of the sediment. The saturate photosynthetic rate (Asat) of P. australis was higher than that of T. orientalis when grown in sediment substrate. But instance water-use- efficiency (WUEi) (A/E) and intrinsic water use efficiency (A/gs) showed the maximum values of two species grown in river water. With significant difference in gs, however, intercellular CO2 concentration (Ci) had no obvious difference in two species which indicated that high Asat value of P. australis might result from the increased carboxylation capacity of the mesophyll, because of the central role of N in photosynthetic enzymes. Our findings suggest that the plants could absorb most of nitrogen in polluted water, while gravel displayed a high capacity for absorbing the suspended matters and phosphate salts. Therefore, biological and physiological pathways for pollutant removal should be integrated.
基金supported by the Major Program of the National Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(No.06KJA36022)"Qinglan Project"scientific and technological innovation team training program of Jiangsu College and University
文摘Chemical investigation of the pollen of Typha angustifolia Linn.has led to the isolation of two new nonacosanetriols,7,8,10- nonacosanetriol(1) and 7,9,10-nonacosanetriol(2).Their structures were elucidated by chemical reaction and spectral analysis. Compounds 1 and 2 exhibited weak activity of antiplatelet aggregation in vitro.
基金funding and support from the Austrian Research Promotion Agency(FFG).
文摘Here,we report the mechanical and water sorption properties of a green composite based on Typha latifolia fibres.The composite was prepared either completely binder-less or bonded with 10%(w/w)of a bio-based resin which was a mixture of an epoxidized linseed oil and a tall-oil based polyamide.The flexural modulus of elasticity,the flexural strength and the water absorption of hot pressed Typha panels were measured and the influence of pressing time and panel density on these properties was investigated.The cure kinetics of the biobased resin was analyzed by differential scanning calorimetry(DSC)in combination with the iso-conversional kinetic analysis method of Vyazovkin to derive the curing conditions required for achieving completely cured resin.For the binderless Typha panels the best technological properties were achieved for panels with high density.By adding 10%of the binder resin the flexural strength and especially the water absorption were improved significantly.
文摘A molecular biology method, fluorescent in situ hybridization(FISH), in which the pre-treatment was improved in allusion to the media of the constructed wetlands(CW), e.g. the soil and the grit, was used to investigate the vertical distribution characteristics of ammonia-oxidizing bacteria(AOB) quantity and the relation with oxidation-reduction potential(ORP) in the Typha latifolia constructed wetlands under three different Ioadings in summer from May to September. Results showed that the quantity of the AOB decreased in the Typha latifolia CW with the increase of vertical depth. However, the AOB quantity was 2-4 times the quantity of the control in the root area. Additionally, ORP in the rhizosphere was found to be higher than other areas, which showed that Typha latifolia CW was in an aerobic state in summer when using simulated non-point sewage at the rural area of Taihu Lake in China and small town combined sewage.
基金The National Natural Science Foundation of China(No.51479034,5151101102)
文摘To probe the influence and the adverse-resistance characteristics of wetland plants in presence of silver nanoparticles (AgNPs), the changes in the physiological and biochemical characteristics (including the superoxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity, soluble protein content, and chlorophyll content) of Typha orientalis exposed to different concentrations of AgNPs solutions (0, 0.1, 1, 20 and 40 mg/L) were explored. Meantime, the accumulation of silver content in these plants was revealed. The results show that under low concentrations of AgNPs, the SOD and POD activities in the leaves of Typha orientalis are strengthened to different degrees. However, high concentrations of AgNPs inhibit the activities of SOD and POD. Under the stress of different concentrations of AgNPs, the CAT activities are inhibited initially and later recovered to some extent. Under the stress of low concentrations of AgNPs, the soluble protein content in the leaves of Typha orientalis increases significantly, but decreases more significantly with increasing concentrations of AgNPs. Low concentrations of AgNPs promote chlorophyll synthesis in the leaves of Typha orientalis , but the chlorophyll content subsequently falls to pre-stress levels. In contrast, high concentrations of AgNPs cause a certain inhibition to generate chlorophyll. Meanwhile, the results show that the silver concentrations of plant tissues increase with the exposure of concentrations of AgNPs and they have a positive relationship with the exposure of concentrations of AgNPs.
文摘Convective heat transfer coefficients, materializing exchanges between solid wall (here typha) and its environment, influence its behavior under excitation pulse. Temperature of wall and its density of flow vary with these coefficients according to its thickness (in depth). This study therefore focuses on the evaluation of convective heat transfer coefficient on front face and the optimal insulation thickness.
文摘Three polysaccharides, TAA, TAB, TAC have been isolated from the pollen of Typha angustifolia L. , and purified by hot water extraction, alcohol precipitation, Sevage method, gel filtration (Sephadex G50) and ion-exchange chromatography on DEAE Sephadex A25 and DEAE-cellulose. Their purities were tested by gel filtration and electrophoresis. Their structures were characterized by paper chromatography of the hydrolysis products, GLC analysis of the alditol acetates, alkylation analysis, 1H NMR and 13C NMR spectra. TAA is mainly composed of a-L-arabinofuanose, β-D-galactose and α-D-galacturonic acid, while the backbones of TAB and TAC are composed of (1→5)-linked α- L-arabinofuranosyl residues.
文摘The aim of this study was to determine the species composition, biodiversity and, relative abundance of epiphytic algae and their relationship with environmental variables on Typha latifolia and Phragmites australis at Lake Gala(National Park). Epiphytic algae were gathered monthly by collecting aquatic plants between March 2014 and November 2014. In the epiphytic flora were a total of 133 taxa were identified, 107 taxa were identified on T. latifolia and 96 were discovered on P. australis. While the mean species richness, species diversity and evenness values of the algae identified on T. latifolia were 46, 1.85 and 0.51 respectively, these values were respectively 43, 1.51 and 0.43 on P. australis. While diatoms were generally dominant, other dominant groups in the epiphytic flora included green algae and blue-green algae. The algae that had the highest relative biovolume on T. latifolia were Spirogyra affinis, Oscillatoria sancta and Gomphonema acuminatum, while the algae that had the highest relative biovolume on P. australis were E pithemia adnata, Oscillatoria sancta and R hopalodia gibba. Results show that species composition of epiphytic algae was different, but diversity values were similar on all the macrophytes. The hydrological pulse is one of the most important factors determining the physical and chemical environment of the epiphytic algal community. It was found that some environmental factors were highly eff ective on community distribution in the epiphyton. Additionally, it was observed that some epiphytic algae species had a substrate preference between T. latifolia and P. australis.
文摘Typha shuttleworthii is the semi-aquatic plant in the modern areal which embraces mainly the ocean districts of Europe. The eastern border of the area of this species is located in Eastern Europe on the territory of Vyatka-Kama Cis-Urals (VKCU). Almost everywhere species is considered rare and is included in the Red Data Books in many European countries. However, on the territory of Russia, T. shuttleworthii is not protected. The rarity of this species makes it necessary to study its natural populations for their protection. In the paper, we present the materials on some biological and ecological features of the Typha shuttleworthii, growing on the territory of Vyatka-Kama Cis-Urals, where the species is represented by its extreme eastern populations. This species is offered to the protection on the territory of the European part of Russia within the Republic of Tatarstan and Udmurtia.
文摘Three polysaccharides TAA,TAB and TAC were purified from the pollen of Typha An- gustifilia L..TAA is mainly composed of α-L-arabinofuranose,β—D—galactose and α—D—galac- turonic acid.TAB and TAC contain the backbone mainly composed of (1→5)—linked—L—arabi- nosyl residue.
文摘Plant-based concretes are produced from plant aggregates and a binder.Plant fibers are mainly composed of saccharides(sugars)and these sugars can decrease the concentration of Ca2+ions in the cement pore solution and delay the formation of hydration products.To improve the interfacial bond between fibers and matrix a chemical treatment is widely used.This study investigates the effect of sodium hydroxide treatment on physical and hygroscopic properties of Typha aggregates.In particular,a 5%sodium hydroxide solution is used to treat these aggregates and their bulk and absolute densities,porosity,water content and water absorption are evaluated accordingly.Results indicate that bulk and absolute densities increase after treatment from 56.44 kg/m^(3) to 122.57 kg/m^(3) and 541.93 kg/m^(3) to 555.17 kg/m^(3),respectively.NaOH treatment reduces porosity of Typha from 89.58%to 77.92%and decreases water content from 1.4%to 1%.The treatment with sodium hydroxide reduces substantially the water absorption of the aggregates.
文摘A greenhouse study was conducted on phytoextraction and accumulation of lead (Pb) and cadmium (Cd) from contaminated soil – water microcosms by the narrow-leaved cattail, Typha angustifolia. The plants were grown in sandy loam soil containing 1,666 and 38.5 mg/L of Pb(NO3)2 and Cd(NO3)2 respectively. The trends of lead and cadmium by T. angustifolia for all soil – water microcosms suggested interaction effects as decreased soil lead concentrations and increased water cadmium concentrations over time. T. angustifolia expressed trends as increased biomass in all contaminated shoots and roots examined. Cadmium uptake in shoot and root biomass slightly decreased when lead was initially added to the soil but cadmium uptake in root biomass increased after 30 days. Data suggested an interaction between lead and cadmium and possible that lead uptake was inhibited when cadmium was present.
文摘The construction industry in Senegal is experiencing an upsurge in the development of residential housing units and administrative buildings within the new Diamniadio municipality, an area located just about 35 km from the capital city of Dakar. Laboratory oedometer or expansive-index tests, however, show poor density and compromised shear strength in the soil samples within the area -posing serious construction problems due to significant volume changes (swellings) that occur when subjected to moisture, thus, bringing into question the structural performance integrity of the soil, and the financial implications of substitute soil types used to compensate for its poor tensile strength. By way, the companies collect the soil of this location (Diamniadio) and throw it to make pile or micro-pile (pious) for their structures. This article demonstrates how we can value the soil of Diamniadio and the Typha Australis in residential building with a reasonable cost. Typha Australis is a plant generally luxuriant within the northern and central belts of Senegal but also known for its negative ecological impacts on the agricultural production of rice. The valorisation of the soil of Diamniadio will pass by the ability to increase its stability or to decrease its shrinkage/swelling rate. When we achieve it, the soil associate with Typha Australis will be used for small bricks which can be useful for partition wall and so the soil will not be ever thrown as a non-useful material. Tests results of soil specimens extracted from the site show a shrinkage rate of 29.19% with estimated cracking depths of 3.5 cm. But by adding gradually Typha Australis, the shrinkage rate will pass from 29.19% to 5.13% with the material treats with 10% by mass of Typha Australis. Moreover, the crackings in the cylindrical specimen disappear. That shows the increase of the stability;thus the composition will be used for building bricks. However, the densities will also be affected by the presence of Typha Australis. The density is decreased from 2032.28 Kg/m<sup>3</sup> for the soil without Typha Australis to 937 Kg/m<sup>3</sup> for the one with 10% of Typha Australis.
文摘Energy consumption in the building sector is constantly increasing and represents more than 44% in the residential and tertiary sectors in many <span><span style="font-family:Verdana;">countries</span><span style="color:#C45911;"> </span></span><span style="font-family:Verdana;">[1]</span><span></span><span><span></span></span><span style="font-family:Verdana;">. Thus, the building represents a real possibility of energy saving and is the subject of several studies particularly in actual context of experimentation</span><span style="font-family:Verdana;"> with materials based on plant fibers (hemp, flax, millet wastage, etc.). These biobased materials such as typha have shown real interest in the buildings construction due to their light and porous nature. It’s in this context that we were interested in typha australis mixed with classic aggregates (cement, sand, gravel 3/8) to make typha’s concrete. On this concrete, we carried out experimental measurements in order to better understand its contributions in the building. The interesting results obtained show that typha australis, which is an invasive and harmful grass, can be valued and integrated among local building materials in the form of typha’s concrete in order to improve the energy efficiency of buildings.</span>